text:
|Publication number
|Publication type
|Application number
|Publication date
|Apr 24, 2001
|Filing date
|Mar 1, 1999
|Priority date
|Feb 4, 1994
|Fee status
|Also published as
|Publication number
|Klaus Draenert
|Original Assignee
|Klaus Draenert
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (8), Referenced by (5), Classifications (35), Legal Events (6)
|External Links: USPTO, USPTO Assignment, Espacenet
This application is a divisional application of application Ser. No. 08/687,362, filed Nov. 4, 1996, now U.S. Pat. No. 5,958,314, which application was based upon a PCT Application No. PCT/EP95/00421, filed Feb. 6, 1995, and which claims priority on Application DE 4403509, filed Feb. 4, 1994.
The invention relates to a process for the preparation of a material comprising a framework consisting of shell-like structures and an interconnecting pore system, a process for the preparation of a material consisting of shaped bodies connected via webs, a process for the preparation of a material which comprises a framework of shell-like structures and whose interconnecting pore system is filled with shaped bodies connected via webs, material producible by means of these processes as well as their use as bone replacement material, artificial bone, implant, filter and drug delivery system.
Lost bone, for instance due to a trauma caused by an accident or after the resection of tumors, after infections or by idiopathically developing bone cysts, has been representing a serious problem for surgeons for a long time. It has, for example, been tried to replace bone artificially, to use animal bone, to process animal bone accordingly such that it is not rejected in humans after it has been inserted or also to preserve bone from humans in freezers and to insert it as frozen homologous bone.
There are various methods for processing animal bone for the use in humans. Ivory, for example, has been also used. A bone replacement which is particularly accepted in surgery is the so-called "Kiel bone chip".
All chemically processed heterologous transplants from animals, however, are incorporated into the host bone incompletely or not at all. The bank bone very often leads to lethal infections, i.a. AIDS infections. Fresh homologous bone transplants are affected by such complications to a much greater extent. In this case, it is even possible to transplant tumors. Therefore, it has repeatedly been tried to develop bone replacement materials and methods by means of which the disadvantages of the immune reaction and the transmission of diseases can be avoided.
In DE-A-39 03 695, a process for the preparation of absorbable ceramics on the basis of tricalcium phosphate is described which can be used as a bone replacement material and in which natural bone material from which the soft tissue has been removed is used as a starting material. Residual organic substance is removed from the bone material by pyrolysis and the remaining bone material consisting of hydroxylapatite is subsequently treated with phosphate carriers and then subjected to sintering. This ignited bovine bone material also exhibits good incorporation properties.
The mentioned materials derived from animals, however, cannot fulfil the demands on bone replacement material with respect to reproducibility of the structure, in particular in view of the material strength and the standardizability of the manufacturing process, and additionally their production is very expensive. Therefore, in medicine it is desirable to produce the used materials, for instance bone replacement materials, fully synthetically. These materials should guarantee maximum strength at a minimum of material and should provide a variety of properties for a variety of indications. It is, for example, desirable to provide a process by means of which on the one-hand bone-like trabecular structures, i.e. a "positive" of the bone, and on the other hand a "negative" of the bone, i.e. shaping negative molds of the medullary cavities of the bone can be produced. By means of such a process, on the one hand the physiological structure of bone could be reproduced and, by means of the negative, on the other hand supporting and guiding frameworks could be provided around which bone grows and which are very rapidly able to take up high loads.
In DE-A-40 33 291, a process is described by means of which the aforementioned demands can be achieved in some respects. In this process, firstly preferably spherical shaped bodies are connected to one another to form a three-dimensional conglomerate of shaped bodies, thereafter a material different from the material of the shaped bodies is molded around the shaped bodies in order to form a three-dimensional framework, and subsequently the shaped bodies are removed so that only the three-dimensional framework is left. In subsequent process steps, the cavity system resulting from the removal of the shaped bodies can be again filled with a ceramic mass, for example, and subsequently the three-dimensional framework can be removed. Thus, by means of this process both a "positive" of the bone and the above described "negative" of the bone can be produced. The preparation of the conglomerate of shaped bodies (negative) serving as the starting material is, however, rather money- and time-consuming and not in any case reproducible.
DE-A-22 42 867 discloses a process for the preparation of implantable, porous, ceramic bone replacement, bone composite or prosthesis anchorage materials. In this process, firstly an "auxiliary framework" is prepared of spheres which approximately corresponds to the pores and pore connections of the finished material, and subsequently a castable ceramic mass is filled into the framework. After the ceramic mass has at least partially solidified, the auxiliary framework is decomposed and removed. The process for the preparation of the initial auxiliary framework made of spheres can be, however, at best standardized in a time- and money-consuming manner and is hardly reproducible.
Thus, an object of the invention consists in providing materials and processes for their preparation, by means of which it is possible to provide on the one hand a material with a three-dimensional framework of shell-like or trabecular structures as a positive, and on the other hand also its negative, i.e. a material consisting of shaped bodies connected to one another, as well as a combination of these two materials, wherein the porosity and the thickness of the supporting structures of the positive material as well as the configuration of the shaped bodies and their connections in the negative material can be exactly and reproducibly adjusted while taking into account the respectively required properties, such as dimensional stability and absorbability.
A further object of the invention consists in providing such materials and processes for their preparation which exhibit increased strength and/or permeability.
These objects are achieved by means of the present invention. The invention thus solves an old problem in material preparation, in particular in the preparation of materials for medicine. By means of the process according to the invention it is possible to simply and reproducibly prepare a porous material with a continuously porous framework having an adjustable porosity and an adjustable strength as well as material properties, such as solubility and absorbability, which are adapted to the respective requirements, wherein the pore system can optionally be filled with a different material.
As "positive", i.e. as material imitating the bone, the material according to the invention comprises a three-dimensional framework consisting of load-bearing shell-like structures which enclose cavities communicating with each other and adjustable in a predetermined manner. These cavities are adjustable in a predetermined manner in particular in that the space taken up by the cavities in the finished material is during the production process of the material firstly taken up by shaped bodies as space retainers, wherein the shaped bodies are appropriately selected and arranged in a mold depending on the demands on the pore system. The material according to the invention as "negative", which can be used, e.g., as an implant, comprises a three-dimensional composite of shaped bodies which are connected with one another via webs whose width and length are adjustable. The shape and structure of these "webs" will be explained hereinafter. The material as positive is producible in that the framework is formed around deformable shaped bodies which serve as space retainers for the cavities and form a "negative", and in that said shaped bodies are subsequently removed.
The finished material as negative can be produced by filling the framework, i.e. the positive material, and subsequently removing the framework.
Depending in the selected materials, it is also possible to form again a framework around said finished negative material, for instance by diffusing a castable material therein, and to remove the negative upon solidification of the castable material. The outer shape of the thus produced positive material corresponds to the framework of the aforementioned positive material but can be of a different material.
Hence, by combining different materials, both positive and negative materials can be prepared from a variety of absorbable and non-absorbable materials. The material according to the invention can be used, for instance, as an artificial bone, as an implant, as a filter and as a drug delivery system.
The use of the material according to the invention in the filter technology is therefore particularly advantageous since any desired porosity is adjustable and furthermore a macroscopically large-pore filter system can be combined with a microporous filter system if the basic material itself is porous. Moreover, the macroporosity and microporosity can be partially or completely filled with an actively absorbing material.
For specific purposes it may also be desirable to provide a material in which the positive and the negative of different materials are present together, for instance a material comprising a metal framework consisting of shell-like structures whose interconnecting pore system, i.e. the "negative" is filled with a ceramic mass, such as tricalcium phosphate or hydroxlapatite. When such a material is used, for instance as an implant, the bone firstly grows well onto the ceramics and a primary composite between bone and ceramics can be formed. The further ingrowth of the bone is also enhanced by the aforementioned effect of ceramics. In this connection, preferably absorbable ceramics is used, but the ceramics can also be non-absorbable. The material consisting of positive and negative can optionally also have a higher strength than the pure positive material.
As starting material for the process according to the invention, preferably deformable shaped bodies are used. For the shaped bodies, a material having a relatively low modulus of elasticity and being relatively easily deformable under pressure is preferred. The shaped bodies serving as space retainers for the cavity system of the finished porous material exhibit preferably the shape of spheres but can also be ellipsoids, granular elements or polygons or mixtures of such shaped bodies. The material for the shaped bodies is selected such that the shaped bodies can be easily removed later on in the further process, for instance chemically or physically.
The shaped bodies are firstly filled into a mold and optionally shaken and form a bulk. In this step, the shaped bodies are preferably not yet essentially deformed. It is not necessary either that the shaped bodies are chemically or physically connected with each other. It rather suffices that the shaped bodies are sufficiently pressed against each other during filling the form with a castable, extrudable or pourable material, which is, for instance, easily controllable by the appropriate adjustment of the injection pressure of the material or by generation of pressure in any other way. By the application of pressure, the shaped bodies are slightly pressed against each other and/or deformed. Depending on how much pressure is applied, the extent of the deformation of the shaped bodies and thus also the width or the cross-sectional area of their points of contact as well as their total configuration, which later in the finished porous material corresponds to the interconnecting pore system, can be easily and precisely adjusted and controlled. DE-A-40 33 291 also discloses the adjustability of the three-dimensional framework of trabecular structures; however, with the process according to the invention, the width or the cross-section of the webs by means of which the shaped bodies are connected with each other can be adjusted in the negative pattern much more precisely and reproducibly, since the contact pressure between the individual shaped bodies is not influenced by air and other undesired inclusions, as is the case when the individual shaped bodies are chemically or physically joined to form a conglomerate of shaped bodies. When in this connection the term "webs" is used, generally the connection between two adjacent shaped bodies contacting each other is meant. The more the shaped bodies are deformed and pressed against each other, the larger is the cross-section of the connection or "web" between the two shaped bodies under otherwise unchanged conditions. Thus, by means of the reproducible adjustability of the connections between the individual shaped bodies in the process according to the invention, the interconnecting porosity, i.e. the arrangement of the pores and their connection channels, can also be adjusted very precisely and reproducibly in the finished porous material, since the shaped bodies and their connecting webs serve as space retainers for the pores and their connections or penetration orifices. It is also ensured that the porosity in the finished material is interconnecting, i.e. that each of the individual pores are continuously in contact with each other. Some of the remarkable features of the process according to the invention are exactly the reproducibility and standardizability of the production with the result of an absolutely uniform structure exhibiting little variation, as well as the far simpler and cost-advantageous production of the material. It has become apparent that despite its better reproducibility and standardizability the material according to the invention can be produced in a fraction of the time necessary for the material according to DE-A-40 33 291.
The simple way in which the preparation of a material according to the invention can be performed is due to the use of easily removable deformable shaped bodies which do not have to be connected with each other but are only pressed against each other, for instance by the injection pressure of the injected material, wherein the width or the cross-section of the "web" between the shaped bodies in the conglomerate of shaped bodies can be reproducibly determined and adjusted, whereby a standardized interconnecting porosity can be produced in the finished porous material.
As material for the deformable shaped bodies, preferably an expandable synthetic material is used. A foamed material consisting of expandable polystyrene (EPS) is particularly preferred, but all other foamed or hollow-spherical shaped bodies consisting of synthetic material and exhibiting the appropriate deformability and easy solubility can also be used. The solubility of the shaped bodies can also be controlled by their porosity (microporosity).
The deformable shaped bodies have preferably a size between approximately 200 μm and several mm, for instance up to 5 mm, particularly preferred is a size between 200 μm and 3000 μm, between 500 μm and 3000 μm or between 1000 μm and 2000 μm. It is preferred to use a specific size fraction of shaped bodies, which is selected, for instance, by sieving or on account of their process of production, e.g. a size of approximately 1000 μm. By the selection of the size of the shaped bodies, the porosity of the finished porous material can be reproducibly, exactly and standardizably adjusted, also small pores of up to a pore size of far below 500 μm, for instance of down to 200 μm.
It is also possible to use a mixture of shaped bodies of various size and/or various morphology as starting material of the process according to the invention.
Other substances can optionally also be used as material for the shaped bodies, such as wax, gels, paraffins, collagens, chitin-like substances or mixtures of such substances, optionally binders having a gel-like character. The shaped bodies can also consist of a composite of finely-disperse material with an easily soluble hydrophilic or hydrophobic binder, wherein the binder can chemically be easily dissolved away.
Preferably, the individual shaped bodies themselves have a microporosity which is between 1 and 40%, preferably between 15 and 25%.
The material which is molded around the deformable shaped bodies should be castable, extrudable or pourable, in particular under pressure. When "castable" material is mentioned in the present description, this is intended to include any castable, extrudable or pourable material. A variety of materials can be used as castable material, depending on the purpose of use and depending on whether the castable material is only an intermediate step in the manufacturing process and is removed later on or whether the castable material forms part of the finished material, for instance the framework consisting of shell-like structures (positive) or the shaped bodies of the finished material (negative) which are interconnected via webs. As material for both the finished positive and the finished negative, for example ceramic materials or ceramic composite materials can be used, preferably such materials which exhibit a high density and can be subjected to sintering. For example, such ceramic materials can be used which are easily absorbed by the body after sintering. However, ceramic materials having a high density can also be used which are hardly or only very slowly absorbed after sintering. Preferred ceramic materials are hydroxylapatite, tricalcium phosphate and mixtures thereof. Hydroxylapatite and tricalcium phosphate as well as the mixtures thereof can preferably be mixed with binders, such as agarose, agar-agar, chitosan or gels, for instance in a ratio of 10:90 to 70:30, preferably approximately 50:50.
However, as castable material or as material for the shell-like framework (positive) or the shaped bodies (negative) connected via webs various other materials can also be used, for instance castable and extrudable plastics which can be both absorbable and non-absorbable, polylactates, polyglycolates, absorbable polyamine acids as well as mixtures thereof, collagens or similar materials or plastics on PMMA basis which are absorbable and/or dissolvable or non-absorbable and/or non-dissolvable in the body. Metals, metal alloys or metal composite materials are also preferred both as positive pattern comprising a trabecular metal framework and as negative pattern with a preferably spherical composite of shaped metal bodies comprising connection webs. In particular for the load transmission as replacement or partial replacement for bodies of vertebra for the fusion of bodies of vertebra, the material according to the invention consisting of shaped bodies, which are interconnected via webs and preferably consist of metal, has very favourable biomechanical properties, which are, for instance, more favourable than those in the open-pore or open-cell metal structure described in DE-C-31 06 917. When metal is used as material for the three-dimensional framework, the metal is preferably formed around shaped bodies of ceramics or gypsum. Silicone, caoutchouc derivatives or related polymers on rubber basis can also be used as material in particular for the three-dimensional framework of the porous material.
Basically, any materials whatsoever can be introduced into the negative or positive pattern, shell-like honeycomb constructions, for example, can be reproducibly and standardizably prepared, or polymorphous materials can be produced by mixing differently shaped deformable shaped bodies as starting material, for instance as implant material. Water-soluble shaped bodies, for instance, can be combined with meltable materials, or sinterable, castable material composites can be combined with water-soluble shaped bodies, or synthetic materials processable by injection moulding, ceramic materials or metals, metal alloys or metal composite materials can be combined such that the shaped bodies are in each case either physically or chemically or in any other way again removable and the three-dimensional shell framework is left as supporting framework. The supporting framework can subsequently be solidified, surface-treated or mechanically finished by physical or chemical methods. The mentioned metals, metal alloys or metal composite materials can be, for instance, castable or processable by centrifugal casting or vacuum investment casting. When, for instance, a ceramic negative pattern consisting of shaped bodies is combined with a metal casting in the form of a shell framework, this composite material can be very highly densified in the so-called HIP process and is mechanically very stable and capable of bearing considerable load. Even after the ceramics has been removed, the remaining trabecular structure or shell-like structure is very stable and capable of bearing extreme mechanical load, represents a very light bone implant through which bone can rapidly grow and which requires very little material. Upon solidification of the material surrounding them, the shaped bodies can be physically or chemically removed, for instance in a water bath, a washing machine or by solvents, wherein in the case of the use of foamed polystyrene or a similar foamed synthetic material, acetone is particularly appropriate as solvent.
For those materials which are removed in the course of the manufacturing process and are not part of the finished material, other substances can also be taken into account, for example gypsum, which can be particularly easily and rapidly processed and is furthermore cheap.
The castable material is particularly well distributed in the bulk of shaped bodies during the filling step, when the shaped bodies are hydrophobic and the castable material is hydrophilic.
The total porosity of the finished porous material is preferably between 50 and 90%, more preferably between 65 and 85%. The material for both the finished shell framework (positive) and the shaped bodies of the negative material, can have a microporosity, for instance between 1 and 40%, more preferably between 15 and 25%.
For specific purposes of use, it can be advantageous to render the passage orifices between the individual pores of the interconnecting pore system of the porous material variable or to enlarge them. This is in particular advantageous when bone cement is sucked into the material or sucked through it or if a faster bone ingrowth is to be attained, wherein optionally a lower resistance to pressure of the material can be accepted. In order to enlarge the cross-section of the connections or penetration orifices between the individual pores, the material with the interconnecting pore system is subsequently chemically treated. A particularly advantageous chemical treatment is the influence of an acid or lye flowing through the pore system. By means of this chemical treatment first of all the thin lamellae of the framework at the point of contact between two pores are attacked and dissolved and thus the cross-section of the pores is enlarged. By the selection of the used chemical agent, the adjustment of its dilution and in particular by varying the duration of the influence of the chemical treatment on the composite material, the original pore connections can be enlarged in a controlled and defined manner and adapted to the requirements. Advantageously, it is proceeded such that a diluted acid flows through the material for a short time so that only the pore connections are enlarged but the structure of the framework as such is not essentially affected or modified. When according to the invention the framework comprising an interconnecting pore system serves as starting or intermediate material for a material consisting of interconnected shaped bodies ("negative"), an enlargement of the cross-section of the connections or "webs" between the individual shaped bodies is effected by an enlargement of the penetration orifices between the pores of the interconnecting pore system of the framework, after a castable, extrudable or pourable material is filled into the pore system for forming the shaped bodies. Thus, the strength of the finished negative material consisting of shaped bodies connected with each other via webs is achieved.
If a particularly high mechanical stability of the "positive" or "negative" material according to the invention is aimed at, massive portions can advantageously be provided in the interior of the material. Apart therefrom, the interconnecting pore system of the framework in the positive material and the configuration of connected shaped bodies in the negative material can be maintained. Preferably, the massive portions in the interior of the material are designed as massive struts, such as reinforcing struts or trajectories. The massive portions are preferably approximately cylindrical and their cross-section has a diameter of preferably approximately 0.5 to 3 mm. The axis of the cylinder preferably extends in the same direction as the expected main load of the material. The massive portions preferably extend longitudinally through the entire material, but can also extend only through part of the material. There can be one or more of such reinforcing struts, for instance 2 to 6, preferably 3 or 4 struts. The massive struts cause in particular an increase of the pressure stability of the material while maintaining the high porosity and bone ingrowing capability of the positive material.
For preparing the material reinforced with the massive portions, both deformable shaped bodies and shaped bodies made of a non-deformable or little deformable material, such as sugar, can be used as starting material. Preferably, in this method, too, deformable shaped bodies are used. In order to prepare the massive portions in the "positive" material, cannulas, such as filling cannulas, are introduced into the mould during the first filling of the mould with the shaped bodies, and the shaped bodies are arranged around these cannulas. Subsequently, the mold is filled with the castable material via the cannulas and/or, as usual, from outside. During the filing, the cannulas are successively removed from the mold and in the material massive portions are formed at those parts of the mould which were before occupied by the cannulas in addition to the framework exhibiting an interconnecting pore system. The removal of the cannulas and the filing with castable material are coordinated over time. The framework of shell-like structures and the massive portions are formed in one casting step so that the entire material is made of a homogeneous material.
When producing the "negative" material with massive portions, space retainers are introduced into the mould together with the shaped bodies, for example in the form of small pipes. These small pipes can either be hollow or massive but have in any case the same outer shape and design as the massive portions to be formed later on in the material. During the subsequent filling of the mould with the castable material, the small pipes are enclosed. Subsequently, these small pipes, which serve as space retainers, are removed, for example by extracting them from the mold or by removing them chemically or physically. The extracted space retainers leave behind cavities within the framework formed. During the subsequent filling of the framework with the castable material forming the shaped bodies, these cavities are filled to form massive portions. Thus, also in this method, the massive portions and the surrounding material made of interconnected shaped bodies are formed in one casting step so that the entire material is homogeneous. However, it is also possible both in positive and the negative material to form the massive portions of different material, e.g., if this is preferred for reasons of strength. For example, fibers, e.g., of ceramics, coal, glass or metal, can be introduced into the massive portions for reinforcement. The material matrix of the massive portions can be of the same material as the surrounding framework and/or the shaped bodies or of a material differing therefrom. In order to form the massive portions of a material differing from that of the surrounding framework or the shaped bodies, the massive portions are produced in a separate method step. The place retainers are for example at first left in the mold until the material is cast, and only then is another material filled in. Massive portions in the form of metal struts are for example particularly preferred which portions are embedded in a negative material of shaped ceramic bodies in order to increase the bending strength. During the final sintering step the ceramic material shrinks on the metal such that ceramics and metal are permanently joined together.
The outer shape of the material according to the invention is optional and is in particular determined by the design of the casting mold used in the method according to the invention. By varying the initial filling volume of the casting mold with the shaped bodies and the number and direction of the injection channels of the castable material, massive portions can purposefully be formed at one or more of the outer surfaces of the material, for example in the form of a thin massive lid. What is called a tricortical cuboid is particularly preferred, i.e. a cuboid made of a porous material in which a massive, thin outer layer is formed at two opposite surfaces of the cuboid and at the surface connecting these surfaces. This massive layer can for example have a thickness of 0.5 to 3 mm, preferably at least 1 mm. Such tricortical cuboids are of particular advantage when using them as bone replacement materials or artificial bones, such as pelvic bone replacement materials.
Preferably, the finished material comprises at least one active ingredient, in particular if the material is used in medical engineering, e.g. for the production of implants and bone replacement materials, as a filter system or an active-ingredient carrier in the form of what is called a "drug delivery system". The finished material comprises preferably 0.01 to 10% of the active ingredient, which is preferably protractedly releasable from the material. For example, the structure of the positive and/or the composite of spheres of the negative, which is connected via webs, can be coated in layers with one or more layers of one or more active ingredients. The macro- or microporosity of the active ingredient can also be reproducibly filled with a mixture of a binder and an active ingredient, the active ingredient being preferably protractedly releasable in the body over a defined period of time.
The added active ingredients can purposefully induce the vessel or bone ingrowth, purposeful treat a local tumor or purposefully contribute to the treatment of an infection. The concentrations obtainable with the present invention by far exceed those of an active ingredient, such as an antibiotic, which could be achieved with a systematic treatment. By a suitable combination with binders or by changes in the porosity, the delayed release of the active ingredient can be adjusted.
As active ingredients, gentamycin, glindamycin, a gyrase inhibitor or another antiobiotic or a combination of two or more different antibiotics can be used. A growth-stimulating active ingredient can also be used as active ingredient, such as an active ingredient of the type of a "bone morphogenetic protein", a growth factor or another chemotactically or hormonally active factor which causes the sprouting or vessels or the differentiation of bone-forming cells and moreover prevents bone destruction. Furthermore, a cytostatic, a combination of several cytostatics or a combination of cytostatics with other active ingredients, such as antibiotics or hormones, can be used.
The macropore system of the porous material can also be filled with activated charcoal or another highly porous adsorbant.
Moreover, a filler, preferably in the form of filler particles can be added to the material according to the invention. As filler particles, 1 to 95%, preferably 1 to 80% of tricalcium phosphate or hydroxylapatite or a mixture thereof or another calcium-phosphate composite or calcium composite can be used. The particle size is preferably 20 to 300 μm and more preferably 50 to 250 μm and the pore volume of the porous filler particles is preferably 0.1 to 0.8 ml/g. The addition of filler particles is particularly preferably when using extrudable plastics materials. If the material according to the invention is made of plastics or metals, a coating with tricalcium phosphate and/or hydroxylapatite is desirable. This is of particular advantage if it is desired that the bone grows through the material. Under load, the bone converts the deformation energy at the interface of smooth implants into a relative motion, which leads to a bone absorption, whereas no such relative motion occurs in the case of rough surfaces, such as surfaces which are coated in such a way.
Activated charcoal or another higher gas- and/or fluid-absorbing material can also be used, preferably in a concentration between 1 and 80% or 5 to 80%.
The following methods are particularly preferred according to the present invention:
A process for the preparation of a material having a three-dimensional shell-like framework, comprising the following method steps: pressing preferably spherical deformable shaped bodies together to form a three-dimensional packing of shaped bodies; forming a material which differs from the material of the shaped bodies around the shaped bodies while deforming the shaped bodies for forming a three-dimensional shell-like framework and removing the shaped bodies so that merely the three-dimensional shell-like framework remains and forms the material.
A process for the preparation of a material with shaped bodies connected via webs, comprising the following method steps: formation of a three-dimensional packing of shaped bodies by pressing deformable shaped bodies together; forming a three-dimensional framework made of a wax or a readily meltable polymer around the shaped bodies; curing the framework made of a wax or a readily meltable polymer; chemical removal of the shaped bodies; filling the continuous cavity system formed by the removal of the shaped bodies with a ceramic mass; and removing the framework made of wax or the readily meltable polymer by applying heat. In this method, ceramic spheres are preferably formed in the cavities. The ceramic spheres can be converted into β and α Whitlockit tricalcium-phosphate composites by the application of heat or can be joined by sintering to form solid bodies of spherical conglomerates, e.g. of hydroxylapatite.
A process for the preparation of a metal material of a shell-like framework, comprising the following steps: production of a bulk material of deformable plastics spheres, e.g., of polystyrene; pressing the spheres together and filling the mould with wax; removing the plastics spheres with a solvent, such as acetone; drying the wax framework; filling a ceramic mass, such as a gel-like mixture of tricalcium phosphate and a binder, into the wax framework; removing the wax in an oil bath and solidifying the ceramic mass; subsequently sintering the ceramic mass in a furnace at a heating rate of approximately 1� C./min up to a temperature of approximately 1300� C. for about 24 hours; placing the formed ceramic body into a box-type furnace and filling it by centrifugal casting with a CoCrMo alloy; sandblasting the ceramic-metal composite and removing the ceramic material with an acid, such as hydrochloric acid.
A process for the preparation of a metal material consisting of shaped bodies connected with each other by means of webs, comprising the following method steps: production of a bulk material of deformable plastics spheres, such as foamed polystyrene spheres; compression of the spheres; filling the volume around the spheres with a ceramic mass, removing the spheres with a solvent, such as acetone; drying, preferably in an ascending acetone series; sintering the formed ceramic shell-like framework in a furnace at a heating rate of 1� C./min up to a temperature of 1300� C. for about 24 hours; placing the ceramic framework into a box-type furnace and filling the macropore volume with a metal alloy, preferably CoCrMo, by centrifugal casting or vacuum investment casting; removing the ceramics in an acid bath, such as hydrochloric acid.
FIGS. 1 to 3 show the filling of deformable shaped bodies into a mold and the filling of the mold with a castable material;
FIGS. 4 and 5 show electron-microscopical pictures of the material according to the invention;
FIGS. 6 to 9 show side and top views of the material according to the invention;
FIG. 10 shows a view of the material according to the invention in the form of a tricortical cuboid; and
FIG. 11 shows a schematic view of a mold for producing a tricortical cuboid.
A particularly preferred starting material for the deformable shaped bodies is Styropor, such as Styropor� F414, i.e., a foamed material of expandable polystyrene (EPS), which has been foamed with pentane as expanding agent. Preferred weights per unit of volume are between 17 g/l and 70 g/l, preferably approximately 20 g/l to 35 g/l. The grain sizes of the foamed material range between 200 μm and 3000 μm.
In order to obtain a dimension figure for a suitable deformability of the deformable shaped body, experiments were made for determining an E-modulus-like parameter for several shaped bodies. For this purpose, the respective shaped bodies were poured into a cylindrical vessel up to an initial height of 84.3 mm. Subsequently, a force F is applied to the bulk material via a die, and the compression, i.e. the change in the initial height, is registered as a function of the applied force. An E-modulus-like quantity is then determined via the formula
in which
E=E-modulus-like quantity
F=force in N
A=surface of the cylinder in mm2
l=initial height (84.3 mm)
Δl=change in the initial height in mm.
The experiments results for several foamed polystyrene types, which differ, e.g., in their weight per unit of volume, the kind of foaming and their particle size, in values for E of about 0.5 to approximately 1.2 N/mm2. Such an elasticity is particularly preferred. The elasticity can, however, be also higher or lower by approximately the factor 10. In contrast, the value E of, e.g., various sugar types is approximately 20 to 180 N/mm2, the sugar bodies being however partly crushed due to the application of force.
As castable material, a mixture of hydroxylapatite powder and an agar solution in a ratio of 10 g powder/7 ml to 25 ml agar solution, preferably 10 g powder/20 ml agar solution, is preferably used. The agar solution preferably consists of a mixture of bi-distilled water with agar-agar in a ratio of 20 ml to 50 ml/1 g, preferably in a ratio of 40 ml/1 g.
FIG. 1 schematically shows a mold 2 with a bottom 4 and a lid 6 as well as filling channels 8. Foamed shaped polystyrene bodies 10 having a spherical shape are filled into the mold 2. When filling the shaped bodies into the mold 2, the latter is only filled to such an extent that the shaped bodies are not subjected to pressure and are not deformed. Subsequently, the mold 2 is filled from the bottom with a ceramic mass 12 as castable material having the aforementioned composition, as shown in FIG. 2. On account of the viscosity of the ceramic mass, the shaped EPS bodies are subjected first to pressure acting in the axial direction to the top such that the shaped bodies are pressed against each other. The result of the reduction in volume thus created is that at the bottom 4 of the mold 2 a polystyrene-free zone 14 is formed which is only filled with ceramic mass and later on forms a dense and massive lid of the finished porous material. Depending on the initial filling volume of the mold 2 and the viscosity of the ceramic mass, the height of the zone 14 and thus the thickness of the lid of the finished material can be varied. The initial filling volume can, however, also be selected such that the entire material formed is porous and no massive lid is formed.
On account of the unidirectional pressure occurring when the ceramic mass is filled in, the deformable EPS spheres 10 are probably first deformed to oval bodies, as shown, e.g., in FIG. 2 by means of the body 16. After completion of the filling step, however, a pressure which has a uniform value in all directions, i.e. an isostatic pressure is formed within the mould. In combination with the elasticity of the shaped EPS bodies and the still soft ceramic mass, this pressure leads to a relaxation of the deformed EPS bodies into their spherical shape. The situation upon completion of the filling step is shown in FIG. 3. After the solidification of the ceramic mass, an isotropic distribution of the shaped EPS bodies is observable. Upon removal of the shaped EPS bodies, for example by means of acetone, the remaining ceramic material has a completely homogeneous structure and exhibits interconnecting spherical pores. The shapes of the pore system and its connection channels correspond to the shapes of the shaped-body composite and its connection channels. The orifices between the pores can subsequently be widened by means of a chemical treatment, for example with an acid or a lye.
FIG. 4 shows an electron-microscopical picture of a material according to the invention with a three-dimensional framework, the shell shape of the framework being clearly perceivable. A line in FIG. 4 corresponds to 100 μm.
FIG. 5 shows a further enlarged view of the surface structure. In FIG. 5 a line corresponds to 10 μm.
FIG. 6 shows a 5 to 6-fold enlargement of a side view of a cylinder of relatively macroporous positive material with a shell-like framework and an interconnecting isotropic pore system.
FIG. 7 shows a top view of such a cylinder. In FIGS. 6 and 7, the homogeneous isotropic distribution of the interconnecting pore system as well as the trabecular or shell-like framework, which is adapted to the bone structure, are clearly evident.
FIG. 8 shows a top view of a cylinder of a relatively microporous "positive" material. The shell-like framework and the interconnecting isotropic pore system thereinbetween is also clearly perceivable in this figure.
FIG. 9 shows a top view of a dense and massive lid of a "positive" material according to the invention. As explained above in connection with FIG. 2, such a dense and massive lid (cover) can be achieved in that when filling the mold with the castable material, an end portion of the mould is completely filled with the castable material and the deformable shaped bodies, which serve as space retainers for the pore system, are completely displaced from this end portion. A material according to the invention having such a lid is, e.g. particularly advantageous for use as a plug in the medullary canal. Of course, it is also possible by means of suitable measures during the production to provide both end portions or different portions of the material volume, for example along the generated surface in the case of a material with cylindrical shape, with such a cover to the effect that the material is in this portion not porous but dense and massive.
FIG. 10 shows an approximately 2- to 3-fold enlargement of a tricortical cuboid with a porous "spongy" inside, two opposing surfaces and an outer surface of the cuboid connecting the latter being provided with a thin massive layer. Such tricortical cuboids have an excellent resistance to pressure. The pressure resistance of tricortical cuboids having a base of 15�15 mm and a height of 7 mm was measured. The experiments were carried out on a universal testing machine Instron 1000 at a speed of load application of 5 mm/min in each case. A such dimensioned, completely porous ceramic cuboid according to the invention has a pressure resistance of about 2 to 4 MPa. A tricortical cuboid which has three massive outer surfaces and was moreover treated for 20 seconds with 25% HCl in order to enlarge the pores has a pressure resistance of 12.2 MPa. A further tricortical cuboid with a partly massive inner structure, i.e. with massive reinforcing struts, and exhibiting the same dimensions has a pressure resistance of 26.2 MPa.
FIG. 11 schematically shows an injection mold 20 with an inner part 21 for producing a tricortical cuboid. The injection is carried out simultaneously at three sides via injection channels 22 a, b, c and distribution connections 24 a, b, c. Reference signs 26a, b, c indicate that each injection is distributed in a fan-like manner to the three impact surfaces where the massive outer surfaces of the tricortical cuboid are formed. Ventilation bores 28 are provided at the "free" side face.
Production of a material (negative) consisting of ceramics for use as a hollow bone-replacement material implant having a reproducible macro- and microporosity
Spheres consisting of foamed polystyrene (EPS), such as Styropor� F 414, having a size of approximately 1000 μm after screening are poured into a cylindrical mould. Wax heated to 75� C. is diecast into the mould via a top gate. After curing the wax, the polystyrene is removed by means of acetone, subsequently, the wax framework is air-dried and then completely filled with a ceramic mass. The ceramic mass consists e.g. of 5 g of tricalcium phosphate or hydroxylapatite or a mixture thereof and 7 ml of a solution which can be made up of 2 g agar-agar and 80 ml water. The wax is subsequently removed from the wax/ceramic molded blank in an oil bath at temperatures of 100� C., and the remaining ceramic mass is solidified for 6 to 7 hours. The basic body thus obtained is sintered in a pottery kiln at a heating rate of 1� C./min up to 1300� C. for about 24 hours and subsequently stepwise cooled for further 24 hours. The ceramic implant thus formed and consisting of tricalcium phosphate, hydroxylapatite or a mixture thereof is what is called a "negative implant" and forms a three-dimensional composite of spheres interconnected via wide webs. Such an implant can in particular be advantageously used for high load transmissions and has pressure resistance of up to 10 MPa, which is extremely high for porous ceramic materials.
Production of a porous material (positive) made of ceramics for use as a bone replacement material having a continuously interconnecting pore system and a trabecular structure
Spheres made of foamed polystyrene (EPS), such as Styropor� F 414, having a diameter of about 1000 μm are poured into a cylindrical vessel and shaken. By means of a top gate, a ceramic mass, which can have the composition according to Example 1, is diecast into the mould and subsequently evacuated. The mold ceramics-polystyrene blank is subsequently cured for half an hour in a refrigerator and then taken out of the refrigerator, and the polystyrene spheres are removed in an acetone bath. After air-drying over acetone, the green compact is sintered for about 24 hours at a heating rate of 1� C./min. in a pottery kiln up to a temperature of 1300� C. Subsequently, it is cooled stepwise for further 24 hours. Then, the ceramics implant which comprises continuously uniform interconnecting pores and has a trabecular or shell-like framework is finished.
Production of a porous material (positive) made of metal for use as a metal implant structured like the spongy substance
Spheres of foamed polystyrene (EPS), such as Styropor� F 414 are poured into a vessel and shaken. The volume inbetween the spheres is filled with wax. The wax is diecast into the vessel by means of a top gate at a temperature of 75� C. Subsequently, the wax framework is cured, the polystyrene is removed in a acetone bath and subsequently the remaining wax framework is dried. Then, a ceramic mass is cast into the wax framework (positive), such as tricalcium phosphate, a mixture of tricalcium phosphate and hydroxylapatite or a mixture of pure hydroxylapatite and a gel-like substance as a binder; the ceramic mass can for example have the composition according to Example 1. Subsequently, the wax is removed in an oil bath at 100� C. and the remaining ceramic mass (negative) is solidified for 6 to 7 hours. The green compact thus produced is sintered in a pottery kiln for about 24 hours at a heating rate of 1� C./min and at a temperature of up to 1300� C. and then carefully cooled for further 24 hours. The ceramic body thus formed and made of spheres with connection webs having a defined cross-section is placed in a mold into a box-type furnace and filled with a CoCrMo alloy in a centrifugal- or vacuum investment-casting method at 1000� C. After removal, the formed ceramics-metal composite is sandblast, and subsequently the ceramics is removed in a hydrochloric acid bath. The implant shows a trabecular or shell-like framework with a standardized and reproducible interconnecting pore system formed thereinbetween which system has approximately spherical pores.
Production of a material (negative) made of metal for use as a vertebral replacement material
Spheres of foamed polystyrene (EPS), such as Styropor� F 414, having a diameter of about 1000 μm are poured into a cylindrical vessel and shaken. By means of a top gate, a ceramic mass is diecast into the free volume between the spheres. Subsequently, the mold blank is hardened in a refrigerator for 30 minutes, the polystyrene spheres are subsequently removed in an acetone bath and the molded blank is dried over acetone. Subsequently, the remaining ceramic body (positive) is sintered in a pottery kiln at a heating rate of 1� C./min for about 24 hours at a temperature of up to 1300� C. Then the kiln is cooled for further 24 hours, and the ceramic positive is removed and subsequently filled with a CoCrMo alloy in a box-type furnace at 1000� C. in a centrifugal casting process. After its removal, the ceramic-metal composite thus formed is sandblast and then the ceramics is removed in an acid bath. The obtained metal framework (negative) forms a composite of spheres which are interconnected via defined wide webs and forms a continuously three-dimensional framework of spheres. This structure can be considered particularly advantageous for the load transmission and the ingrowth of bone trabecula in their physiological morphology. Such an implant is moreover highly stable and can directly be used as a vertebral replacement material.
In the aforementioned examples, gypsum can, e.g., also be used instead of the aforementioned ceramic mass, if the mass is removed later on and does not constitute part of the finished material, such as in examples 3 and 4. The use of gypsum is particularly inexpensive and unproblematic since gypsum cures quickly and can simply be processed. Gypsum is usually stable at temperatures of up to about 1050� C. and can therefore be used in combination with metals or metal alloys whose melting temperature is maximally 1050� C.
Implant reinforced by struts and trajectories
For vertebral replacement materials or for blocking two bodies of vertebra after a vertebral-disk excision, bone cubes or cuboids, which have to take up very high forces of pressure, are used. In the case of such surgical interventions, there are different types of remainders of bodies of vertebra. If there are still cortical elements, an implant is preferred which can be ingrown starting from its periphery from all sides. In such a case, a bone-replacement material implant without cortical proportions has to be used. In order to impart the necessary pressure resistance to the implant such that it withstands the aforementioned high stresses, the implant is reinforced in the axial direction with massive struts according to the invention.
|Cited Patent
|Filing date
|Publication date
|Oct 1, 1970
|Oct 24, 1972
|Tecna Corp
|Surface or lining compatible with blood or other tissue
|Nov 10, 1977
|Jul 15, 1980
|Takaji Funahashi
|Process for preparing open-cell sponge rubber printing material having small and large interconnected cells
|Feb 26, 1979
|Oct 7, 1980
|Dayco Corporation
|Microporous elastomeric material and method of manufacture
|Mar 29, 1993
|Jun 4, 1996
|Draenert; Klaus
|Bone replacement material made of absorbable beads
|Aug 31, 1972
|May 2, 1974
|Battelle Institut E V
|Verfahren zur herstellung implantierbarer, poroeser, keramischer knochenersatz-, knochenverbund- oder prothesenverankerungs-werkstoffe
|Oct 19, 1990
|Apr 23, 1992
|Draenert Klaus
|Werkstoff und verfahren zu seiner herstellung
|Title not available
|Title not available
|Citing Patent
|Filing date
|Publication date
|Aug 23, 2002
|Nov 16, 2004
|Radiant Holdings, Llc
|Method for producing silicone foam utilizing a mechanical foaming agent
|Aug 23, 2002
|Aug 26, 2004
|Terrell W Ferguson
|Method for producing silicone foam utilizing a mechanical foaming agent
|Aug 23, 2002
|Sep 9, 2004
|Ferguson Terrell W.
|Silicone foam
|Oct 21, 2011
|Apr 25, 2013
|Terry M. Sanderson
|Foam material with ordered voids
|Aug 23, 2002
|Mar 27, 2003
|Radiant Holdings, Llc
|Method of producing silicone foam utilizing a mechanical foaming agent
|U.S. Classification
|428/307.3, 264/227, 264/49, 264/321, 264/42
|International Classification
|Cooperative Classification
|European Classification
|Sep 27, 2004
|Fee payment
Year of fee payment: 4
|Oct 20, 2005
Owner name: THURGAUER KANTONALBANK, A CORPORATION CHARTERED IN
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:DRAENERT, KLAUS;REEL/FRAME:017105/0456
Effective date: 20050915
|Oct 1, 2008
|Fee payment
Year of fee payment: 8
|Dec 3, 2012
|Maintenance fee reminder mailed
|Apr 24, 2013
|Lapse for failure to pay maintenance fees
|Jun 11, 2013
|Expired due to failure to pay maintenance fee
Effective date: 20130424


text:
Object Oriented Software
- OS: WinME ×
Vaca - A C++ Win32 API wrapper
Visual Application Components Abstraction: A library to program applications for Windows using C++, STL and a simple OOP approach. It's a wrapper for the Win32 API, with additional functionality like dockable tool bars, layout managers, signal/slot,1 weekly downloads
Program Execution Monitor
-- PEM - A tool like a visual debugger with a rich user interface(but there is much more to this than a debugger), it is better described using the example of Eclipse debugger. This tool inverts the debugger to develop code.
A COM+ implementation to search in a directory inside text files.It´s very fast in compare with normal windows search. In my tests it´s searched at last 100Mb of text files in 5 minutes in the same enviroment.

subset: commoncrawl


text:
Wimped out on first time trying FPV on my hexacopter, any help to get over the fear
I took my FPV equipment and spotter to a HUGE park with no one there and I was going to try to fly FPV and I chickened out.
I only planned on hovering within 10-20 feet of me for the first time.
I put on my goggles and was ready to try but couldn't do it.
I have almost $1,000 into this and it's only a few weeks old and didn't want to wipe it out.
I've since sold my goggles, BUT I decided to give it another go and bought a pair of Vuzix 920's and will attempt it again.
I have a (Way Cheaper $200) new Radian Pro that's been sitting in a closet for 6 months that I was thinking of attaching everything to but I don't know if that would give me the same feeling as the hexacopter. I fly gas helis so maybe that helps some.
Just looking for any suggestions to help me. I'm a very experienced general aviation pilot with tons of hours so I think that once I get going I'll be fine.
I just need help taking that first step. When I put the goggles on I got the same feeling as when the instructor got of the airplane when it was time to solo almost 20 years ago.
Last edited by jasper7821; Mar 27, 2012 at 06:18 PM.
Hi Jasper,
FPV'ing any mulitrotor is always scary for the first several times. It's a lot like scuba diving for the first time and can be very claustrophobic compared even to flying a plane FPV. Starting out in a large open park with a spotter (in low wind conditions) is the best you can hope for. Use at least a 2.8mm (2.5mm is better) wide angle lens on your FPV cam and always keep moving forward while flying. With that said, you really just have to "get your crashes in" to finally get it. It was about 5 to 7 complete flights in (and crashes) that I finally wasn't wanting to yank the goggles off and throw in the towel. FPV via multicopter is very different from a plane, but is great once you get the hang of it.
/I'll often let a LOS R/C flyer at the field fly my FPV plane thru goggles while I moniter video on my laptop, but I'd never let anyone fly my quad via FPV. It's too risky, too much liability, and there's too much experience required to fly it via 1st person. When they ask if they can try it, I say nope, "Build your own FPV quad and get your crashes in to build up your experience level."
Last edited by patricklupo; Mar 27, 2012 at 06:25 PM.
I have a KX191 camera from Range Video.
I think I'll take my Graupners off and put the stock props back on a give it another go when my goggles show up.
I have no idea if the Vuzix 920's are any good but I just thought they looked ok.
I have 900mhz so I couldn't use some of the other ones out there.
I've seen lots of crashes with the DJI quads and Hexas and they're built pretty tough. I thing that if I had a minor crash I'd only HOPEFULLY bust a prop or two so I think I'm stuck trying with this one.
I just recently completed my first FPV with my Naza stock Quad kit. I have to admit the first time my fingers were shaking so bad I almost didn't take off, but I did. Once I was in the air I became comfortable enough to fly up and hover in front of myself for a few seconds. That was two weeks ago and I am anxious to fly again. I had the good fortune to have and experienced FPV pilot as my spotter. As Patrick said always fly forward, I almost hit a goal post and probably would have been it not for my spotter. I now have gotten over the jitters and look forward to my next FPV adventure. Here is the boring video, nothing special but it was my first time.
That looked pretty ballsy Gary for your first time, you went pretty high.
Congrats, That's way more than I would have done, you seem pretty confident and not scared like I am.
That was awesome.
Jasper, I feel ya. I've been flying my heli FPV for years, and I still get the jitters when I go under the hood. I think having someone there to watch out for others, keep and eye on things LOS, and just providing moral support, is a good idea. Especially the first few times out.
I have to echo the others suggestions of planning to crash a few times. Then you are lucky if you don't! Heli crashes are expensive and timely. I built an RCExploere DIY tricopter to fly FPV with, in addition to the heli, because one of its major benefits is that is designed to crash with minimal damage and minimal cost to repair. Things just pop off instead of breaking. And if something breaks, it will likely be a $1 prop, or a $1.50 wooden arm stick you can pick up at Hobby Lobby.
Another thing that can sometimes make it a little easier to transition to FPV is to use an external monitor vs. goggles. My main setup is Headplay goggles. But I also have a 21" battery powered monitor setup that lets me switch back and forth a lot between LOS and FPV without having to put on and take off goggles (a 10" LCD would do the trick, though). Sometimes that can be a good thing, sometimes bad. But if going "under the hood" with the goggles is a little scary at first, using a regular monitor can be a good stepping stone.
Also, you mentioned something about Gary going so high on his first time out (nice first flight, btw Gary!). I actually feel like about 100' of altitude is better for the first few FPV flights than staying close to the ground. It may sound and feel counter-intuitive at first, but once you get some distance between you and the ground, you feel more free to yank the sticks around a lot and get a feel for the way the craft is behaving. Close to the ground, you can't really do that and not expect to hit something.
One last thing: Flight sims. Any type of RC sim will do. I haven't looked at your posts to see if that is something you're already doing, so forgive me if you are. But simulation practice really does a lot for motor memory development and orientation. I went whole hog several years ago and got Realflight. I recommend it.
I hope you find some of this information helpful. Good luck!
Meh, if you can fly it LIS then it will be tons easier FPV. Just set it up so you can see the two motors or arms they are on from the camera. It will give you perspective as to how the copter is sitting in the air. When you take off, don't muck around just get it up quickly to about 8-10 feet high. Once there, just practice keeping it stationary and then slowly move up to forward flight and using yaw control (rudder) then get the copter facing yourself and try to keep it about 5 metres away from yourself.
Don't hesitate, just get the goggles on and do it! You will kick yourself for not doing it earlier.
Forget the spotter, forget the screen, just find somewhere open with little or no wind and NO AUDIENCE! Just do it!
I've never flown an FPV quad, but I can tell you from experience that trying something new and a little scary is MUCH easier with no audience.
No matter how cool you think you are, you are still a human being. And as such, you will feel some subconscious pressure to perform well if others are watching you. Of course, this effect varies greatly from person to person, but we all feel it...
That pressure to perform will cause you to make mistakes. Almost guaranteed!
Of course, having a skilled helper is OK. But NO AUDIENCE!!!
Thank you very much everyone for the assistance.
I guess higher is safer but lower feels safer in my mind
When I learned to power paraglide my instructor would always get mad at me because he kept telling me higher is safer in case of a wing collapse. But I was always just skimming across the ground because that felt safer.
I guess I'm going to have the attitude of just screw it and do it. I'll go into the desert alone and see what happens.
I'll have my fingers crossed.
Thanks again
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text:
Now that the movie is completed, Fukunaga's struggle is far from over. Several theater chains, like Regal and AMC, are boycotting the film since it will simultaneously be available on Net- flix. Still, Fukunaga is emphatic that audiences should try to see it on the big screen. "The impact and power of this film comes from experiencing it all the way through," he says. "At home, you get a text—you slip out of the experience." Then there's the issue of convincing people to stay seated through the carnage. One of the film's more gruesome scenes shows Agu killing his first victim by swinging a machete into the top of the man's skull.
"I know inevitably there will be people who can't make it through the film," Fukunaga says. "But I also couldn't diminish it so much that it didn't feel authentic." He hopes that infusing the first 20 minutes with humor and introducing the audience to Agu's family will create a bond that carries them through. "I'll read a terrible headline, and then move on with my life," he says. "But you can't erase the emotional memory you have after experiencing this movie. It will always stay inside you."
Early reviews from the Toronto and Venice film festivals laud Fukunaga's striking cinematography and suggest Elba could finally get an Oscar nod after being overlooked for his lead role in 2013's Mandela: Long Walk to Freedom. The plot remains a punch to the gut. But crafting a lighthearted romp isn't on Fukunaga's ambitious agenda. "I'd rather be a documenter of our time," he says, "than pretend none of this is happening." □
Spielberg's Bridge to the Cold War
LIKE A GRAY FLANNEL SUIT in a hall of mirrors, Steven Spielberg's taut, assured thriller Bridge of Spies takes a grownup approach to an enthralling, true-life espionage tale. James Donovan isn't a spy; he's a decent everyman. In other words, Tom Hanks, in a deceptively wry turn. A stolid Brooklyn insurance lawyer, Donovan is chosen in 1957 by the U.S. government to defend captured Soviet mole Rudolf Abel (a soulful Mark Rylance). Abel is imprisoned but becomes useful years later when Air Force U-2 pilot Francis Gary Powers is shot down over the Soviet Union while taking intelligence photographs. Donovan heads to East Germany to negotiate the exchange of Abel for Powers, winding up at the Glienicke Bridge, where secret East-West pass- offs occurred.
This covertly brawny film, with a script by Matt Char- man and Joel and Ethan Coen, has plot points that click like pegs under Spielberg's tight direction. In his fourth pairing with Hanks, Spielberg again examines the furtive face of justice and issues another masterful ruling.
Hanks plays James Donovan, negotiator of a spy exchange


text:
Posted by Brad on 23:30:42 1/8/2015 from 126.96.36.199:
I just bought my first home. We had a termite inspection that was suppose to be done 10 days prior to closing per contract. I found out today ,1 month and 4 days after closing that we have termites. They were found in a corner of a window that just a small portion that we know of now. I found that the inspection was done over 30 days prior to closing and not the 10 days that the contract stated. The termite inspector said that the work would have to come out of my pocket because this wasn't there when he done the inspection. but they haven't swarmed since I have been in the home and there was evidence of a swarm in the house is the way my guy found them. Can anyone help and tell me what can be done. Is that inspection something they have to stand to for a certain amount of time?
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Enjoy a fun duck tour on your next trip to Branson! Climb aboard for an exciting ride on one of our amazing land and water duck vehicles. Ride through the historic streets and neighborhoods. Splash down into the water and enjoy a cruise. Quack along with the Captain and music. Your entertaining captain mixes fun, music, and history into an interactive land and water experience.
Branson's fun thing to do. Ride through the scenic Ozarks. Climb to the top of the Mountain (aboard our Duck, of course). Discover the history behind some of America's unique military vehicles. Splashdown and Cruise Table Rock Lake. Drive the duck, if you want. Quack along with the captain and the music aboard this 70-minute Ozark adventure.
Our Ducks are built from the ground-up exclusively for Ride The Ducks and its partners. Our vehicles resemble the WWII DUKW in appearance only. The Ride The Ducks duck uses the latest in marine design and safety. They are regularly inspected, tested & certified by the United States Coast Guard to ensure a safe and comfortable experience for our guests.


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Welcome to GTPAC
The Procurement Technical Assistance Program: Connecting Business To Government
Introduction to Government Contracting – August 18 2016
CDC Industry Day – May 3, 2013
The Centers for Disease Control & Prevention (CDC), a unit of the U.S. Dept. of Health & Human Services, held a small business Industry Day on Friday, May 3, 2013 at the Georgia Tech Research Institute. The event was hosted by the Georgia Tech Procurement Assistance Center (GTPAC). This day-long event featured presentations by officials from the Dept. of Health & Human Services and the CDC as well as representatives from the Environmental Protection Agency (EPA), the General Services Administration (GSA), the Dept. of Housing & Urban Development, and the Small Business Administration. Two small businesses also made presentations. The registrants' list as well as copies of all of the presentations can be downloaded and viewed from the files posted below:
[slideshow id=3]
Downloadable Files
- Registrants-CDC Industry Day – May 3 2013
- CDC – Dale DeFilipps – CIMSSmallBusinessIndustryDay 05032013
- CDC – Jeffery Napier – Small Business Industry Day Welcome 05.03.2013
- CDC – Jeffery Napier – Welcome 2013 05.03.2013
- EPA – CDC SB Presentation 05032013
- FedBid – CDC – 05.03.2013
- GSA – Rebecca Vanover – CDC- 05032013
- HOW TO DO BUSINESS WITH HHS – April 2013
- HUD – CDC Small Business Presentation 05032013
- JE Group – CDC Small Business Conference Seminar 05.03.2013
- Rainmaker Growth Partners – LinkedIn for Federal Contractors 05.03.13
- SBA – Joyce Thurmond – CDC Industry Day 05032013
- Welcome from GTPAC – CDC Industry Day – 05032013
U.S. Fish and Wildlife Small Business Outreach Event – Apr. 8, 2013
On April 8, 2013, the U.S. Fish and Wildlife Service sponsored a small business outreach event at the Georgia Tech Research Institute. The event was hosted by the Georgia Tech Procurement Assistance Center (GTPAC). This day-long event featured presentations by officials from the Fish & Wildlife Service as well as representatives from the U.S. Army Corps of Engineers, the Dept. of Veterans Affairs, USDA's Forest Service, the National Park Service, the Environmental Protection Agency, and the Small Business Administration. Copies of those presentations can be downloaded and viewed from the files posted below:
- GTPAC – Bids prep – presentation – 040813
- US Army COE – USFWS – 040813
University System of Georgia 2012 Procurement Expo
The Georgia Tech Procurement Assistance Center (GTPAC) participated in the recent University System of Georgia (USG) Procurement Expo. Hosted on Oct. 15, 2012 by the University of Georgia, the expo featured officials and speakers from the purchasing offices of most of the state's universities and colleges, as well as the state's purchasing arm, the Department of Administrative Services (DOAS).
Georgia Tech panelist Chuck Schadl introduced the audience to the training and services offered by both GTPAC and The Contracting Education Academy at Georgia Tech. Chuck presented a 13-question quiz to the audience and used the answers to educate the vendors in attendance to procurement rules and procedures followed by USG schools and state agencies, including changes in purchasing rules that became effective on July 1, 2012.
You may download a copy of Chuck's quiz here: USG 10.15.2012 PDF
USDA Forestry Service/Georgia Tech Procurement Center Joint Conference
hosted a joint conference on February 9,2011 at the Georgia Tech Research Institute.
The objective of the conference was to provide potential bidders with information
on the upcoming Forestry Service A & E solicitation. In addition, the SBA provided
the latest update on the Woman-Owned Small Business Program.
- Women – Owned Small Business (WOSB) Federal Contract Program (PPTX file, PDF file)
- Doing Business with the USDA Forest Service (PowerPoint file, PDF file)
- USDA Forest Service Architectural & Engineering Business Opportunity Conference (PowerPoint file, PDF file)
- Forest Service and A/E Services (PowerPoint file, PDF file)
- USDA Forest Registration (Excel file, PDF file)
GSA – PBS educational and matchmaking conference
The Georgia Tech Procurement Assistance Center and the Region IV office of the General Services Administration (GSA) – Public Building Service (PBS) co-hosted a conference on August 31, 2010 at the Georgia Tech Research Institute meeting facility. Conference presentation documents, and other data are available for your review by clicking on links below.
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Emergency Response Contracting Opportunities for Georgia Businesses
Video: How to successfully identify, compete for, and win government contracts.
Audio: Atlanta Business Radio's Federal Government Contracting Forum Special
Below is an audio link to the March 17, 2010 radio broadcast featuring Terri Denison, SBA District Director; Chuck Schadl, GTPAC Program Director; and Gwen Miles, Fort McPherson's Small Business Specialist. The broadcast was facilitated by GTPAC client Kevin Grimes, chief executive officer of CFO Leasing, Inc. and hosted by Atlanta Business Radio's Lee Kantor and Amy Otto.
Video: Sample GTPAC Classroom Instruction
Below are excerpts from recent GTPAC classes. Actual instructional videos are coming soon to this page.


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Vero Beach, Florida 3296
United States
|Areas of Practice
|1) Appellate Practice Bankruptcy Child And Family Criminal Criminal Appellate Debtor And Creditor Estate Planning Family General Practice Litigation/Trial Advocacy/Advocacy Marital And Family Mediation Trial
|Law School
|University of Florida Levin College of Law
|Admitted Year
|West Virginia University (B.S., 1997)
|Most recent firm
|Menz & Battista, P.L.
A. Harrison Barnes is a well-known attorney throughout the United States. As a member of the Malibu community, Harrison is committed to serving the needs of Malibu residents and businesses in legal matters.
Benjamin P. Smith is a partner in Morgan Lewis's Litigation Practice. He is a trial lawyer with a particular focus on high-stakes disputes in the biotechnology, medical device, and internet industries.


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Deputies make arrest in July armed robbery case
CHARLESTON, S.C. (WCIV) - Deputies say they made an arrest Thursday for an armed robbery that happened in late July.
According to spokesman Jim Brady, Tamar Jacquez Mikell was arrested for the armed robbery of 1814 Produce Lane on Johns Island.
Brady says Mikell pulled a firearm on July 20, 2012 and took the victim's wallet and cash before fleeing in a red, two door car.{} The driver of that vehicle has not been identified.


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What has kept me from doing a post like this is the abundance of good advice on the subject from other bloggers. But what I realized is that I love to read and re-read posts on the same subject from different points of view, so what the hell.
One of the things I get asked the most is "That skirt/top/necklace/whateveritisthatI'mwearing is great! Where did you get it?" 9 times out of 10 I've bought it second hand. The next question that usually follows my response of "Thanks, it bought it second hand" is: "Can I go shopping with you?" So now I'm posting my own advice on the subject right here for you to peruse, refer to and enjoy!
If you'd like to successfully shop second hand there are a few things to keep in mind before you even grace the doors of a store - a shopping strategy if you will. These tips will hopefully help keep you from being overwhelmed, which seems to be every new thrift shoppers main complaint.
And don't forget to hit up the local thrift shop if you are travelling. I often skip the mall and head straight to the local second hand store when I'm away from home.
Wear shoes you can easily slip on and off, like flats, sneakers or pull on boots.
I'd also recommend wearing separates. It means you'll have something to wear with that top or bottom that you're trying on. Thinner separates, weather permitting, will also give you a leg up. Sometimes I get lazy and don't want to try things on in the fitting room, so I pull them on over my clothes in the aisle and wearing something thin means you'll have a better idea of how it fits.
Bring a bag with a shoulder strap. You'll need your hands free to shop.
3. Have a budget.
I know this sounds silly if you're shopping second hand, but it can be easy to buy a lot and overspend because everything is cheap. When I started shopping second hand I would get over-zealous, bring way too much home and spend waaaay too much money. And more often than not most of what I'd buy would just end up hanging up in my closet unworn. So I started shopping with a budget. I found it helps me cut the wheat from the shaft. I only take home the things I really love and leave the things I feel so-so about behind.
You don't need much. $20-30 can buy you a lot.
4. Know what you're looking for, but also be open to what comes your way.
Having focus and knowing what you're looking for in a thrift shop (especially a large one) can help keep you from buying things you don't need. The simplest way to do this is to evaluate your closet before a trip. What are you missing in your wardrobe?
Being the A-type personality that I am, I keep a small written list in my wallet of the items I need to flesh out my closet (i.e: red skinny belt, black mid length skirt, navy flats etc…). When I feel overwhelmed or don't know where to start I get out the list.
On the other hand, once you're in the store don't get too married to your list either. Let the "thrifting gods" guide you. If you come across a fabulous jacket that you absolutely love, fits like a glove and you know you would get a lot of wear out of, but isn't on your list buy it anyway! Some of my favourite pieces are ones that the universe has dropped into my lap.
And that's just to start! We haven't even walked into a store yet…
Tomorrow I'll post some tips on finding quality items and keeping focused while you're at the store.


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Karate Training
Karate is a fight technique that stems from centuries of both armed and unarmed combat. This fight technique has evolved over hundreds of years and has been perfected over time by many generations especially those of Chinese and Japanese origin. This article seeks to describe various important aspects of Karate training and some of the muscle building supplements important in this kind of training.
The first step in karate training is to rid one's mind of all thoughts so as to enhance concentration. In meditation, one needs to breathe in through the nose and out through the mouth. This kind of breathing is very helpful in clearing one's mind in preparation for karate training. Although there is no time limit, 10 minutes are enough to help one clear his/her mind.
Warm-Up and Stretching
After meditation, one needs to do some warm-up exercises for instance by running around; or by doing some pushups, leg lifts or sit ups. Warming up helps in loosening muscles and eases tension. After warming up, it is important to stretch a bit so as to further loosen muscles and reduce one's chances of getting injured in the training.
The Basics
There are many types of karate, but there are some basic stances that are common in all of these types. The following are some of the common stances:
- The Natural Stance
In this stance, the karate practitioner points one of his foot forward and the other one backwards and 45 degrees outwards. Moreover, the feet need to be placed apart in a natural walking distance.
- Front Stance
This is similar to the natural one, but the feet need to be placed further apart. Moreover, the practitioner's weight needs to lie more on the front leg.
- Back Stance
This stance is also similar to the natural stance, but the practitioner puts his weight more on the hind leg. In this stance, the practitioner may also raise his front heel.
- The Ready Stance
This is the stance that one in training needs to start with. There are three major options in this stance:
- Fukyugata –heels are placed together and toes point 60 degrees outwards
- Pinan – feet are placed shoulder width and toes point 45 degrees outwards
- Naihanchi – feet are placed parallel to each other
Staying In Balance
Karate is a technique that needs the trainee to maintain balance. For the stances to be done correctly, the trainee needs to maintain balance. Furthermore, this balance needs not disappear once the trainee starts throwing kicks. To keep balance, one needs to be aware of his/her center of gravity (COG); spreading the feet helps lower the COG. It is also important to note that lowering the COG also reduces speed and mobility. Therefore, it is important to find a good COG/speed balance in karate training.
Punching and Blocking
There are several crucial punching techniques in karate, like straight punch, elbow strike and back fist. As much as punching is important, blocking is equally essential to counter attacks. The most important blocking tool is one of the arms; while using the other arm to attack immediately after blocking an attack.
There are several important kicks in karate, for instance the front, snap and back kicks. Doing repeated kicks of any particular type helps in strengthening the legs.
Karate training may appear like rocket science, but with persistence, you can go ahead and win the black belt. As you train, check out these useful karate training supplements:
- MMA Training & Recovery Supplementation
- Whey Protein
- Glutamine
- Creatine


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Schmidt continues rehab at Triple-A
Schmidt continues rehab at Triple-A
Jason Schmidt resumed his injury rehabilitation assignment on Saturday night, pitching 2 2/3 innings and allowing one earned run for Triple-A Las Vegas at Fresno.
Schmidt, one year after career-threatening shoulder surgery, had made four rehab starts for Class A Inland
With his fastball clocked between 88-91 mph, Schmidt made 45 pitches (24 strikes), allowing three hits, two walks with one strikeout.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.


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This Opinion piece looks at e-signatures and digital signatures, the legal and the technical.
Walby, who was CEO of Central Corporate Credit Union, took over as CEO of Alloya on April 30 after CenCorp merged into Alloya.
They improve member service, speed up the loan process and comply with open-ended lending regulations.
"We compensate board members more out of a sense of fairness than anything else," explained Lin Hodges, president/CEO of Associated Credit Union of Norcross, Ga.
Part two of this analysis of credit union board compensation by Credit Union Times. From our July 10 print edition.
The reaction among the roomful of credit union board members was shock and awe. Explanations for board pay vary as do questions raised.
Part one of this analysis of credit union board compensation by Credit Union Times. From our July 3 print edition.
Developing innovations to help credit unions improve members' financial lives is focus of project.
Hirings, promotions


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Book Writing For Everyone
The world is full of bad writers, don't be one of them. Take advantage of expert advice and learn how to write a book that engages the reader and brings you the recognition you deserve. Easy to follow guides on how to write a book take the mystery out of the writing process so you can start writing that book you have always dreamed of but didn't know how.
Thank you to MTeevan Plant Hire for supplying all the tools needed to build our new office! MTeevan's plant hire provides the complete tool & plant hire solution in London area. You should check them out.


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Kelly Rowland is featured on popular Italian and Latin pop singer Tiziano Ferro's single "Breathe Gentle". They even shot a video for the single that's been recently released. Rowland seems to be moving on with her career since spliting with manager Mathew Knowles earlier this year, and I'm proud of her. Not many Americans know who Tiziano Ferro is but Kelly's camp is making a smart business move. She isn't a big star in the U.S, so why not make her a big star over seas! I just wish her next album will do well in the U.S as well as abroad.
Tiziano Ferro Feat. Kelly Rowland0


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Have you ever wondered what the best voicemail message to use in Network Marketing?
How about email?
How about FB private message?
Or even text.
I find that many network marketers, hide behind technology. They use a copy and paste method to mass text, email, fb message people.
They do a sales pitch on someone's voicemail.
If you do this, chances are that your prospects don't contact you back. Most of the time, they'll even avoid your phone calls because they don't want to be pitched.
If you leave a link on email, fb message or text to somebody, people mentally recognize it as spam. They either dismiss, or delete the message after scanning it and rarely do they ever follow the link.
You might wonder, "So what message should I use?"
For VM or text
"Bob, it's Kenny. I need to talk to you about something. Can you give me a call."
For email or social media,
"Bob, I want to talk to you about something. What's the best number and the best time to reach you."
Don't hide behind technology. Just talk to your prospects on the phone or face to face. That's your best chance at selling your prospect.
Create a great day!
Find me on fb: https://www.facebook.com/kennysantoscreator
Get more MLM Success Tips here: http://kennysantos.com/topic/business-ownership/
People often tell me that they have no one to talk to, that they don't have leads to invite and present to. It's a big problem to have but it's also easy to solve. If you want to know how to get an endless supply of leads for free or very little cost then go http://kennysantos.com/products/ and solve that problem.
What's the 90 in 90? http://kennysantos.com/how-to-ramp-up-your-business-in-network-marketing/


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"Two or three wrongs ought to make a right,
Vengeance to all and to all a good night"
And Dan Baily can really scream this one out!
InfernoRaton April 30, 2003 Link
Lyrics submitted by ruben
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Knife Party Pushes 'Abandon Ship' Release Date Back
For the last couple of months, news, previews, and "leaks" have been circulating around the dance music community regarding Knife Party's highly anticipated debut full length album, Abandon Ship. The Australian duo consisting of Rob Swire and Gareth McGrillen, both former members of drum & bass band Pendulum, originally promised that their album would be out on October 27th, a week before their headlining slot at HARD Day of the Dead in Los Angeles. However, in a message sent to their fans via their Twitter, Swire and McGrillen regretfully informed us that the release date for their album had to be pushed back to November 10th from their original October date.
Though their 13-track album will not see an official release until November 10th, this delay does not solely rest on Swire and McGrillen's shoulders. As they explain in their full apology, which you can find below, they have convinced their management to stream the full album online a week before the official release.
Until then, Knife Party fans can hold themselves over by watching the first official music video off of Abandon Ship for their track "Begin Again."


text: Hi I am new to the forum. I have an issue. I just bought the droid increadble on Tuesday. Today it started being wierd. I believe it has the slcd screen. I was rooted, and used ninja morph to remove some bloat. It was great untill i rebooted and I had lost the bloat and the scence and gmail stuff didnt work. So i thought i could just re-flash and get everything back no problem right ; wrong. I tried several Roms and nothing would flash. I then copied all the \system\app stuff from the clockwork mod update file. So i had everything back where it need to be and nothing showed up in the app drawer. Titainm backup and rom manager have been no help. I then installed and loaded a 140MB PB1IMG.zip that was suppose to be a official leak. So i put it on my sd card, hboot, and great it working. It turned off not reboot. It turned off, black screen, nothing. If i remove the battery and charger then put the battery in and the charger I get the orange light. If i hold vol up and power i get the qULCOM 3 vibrating thing. IF i hold vol down and power nothing. If i just push the power it vibrates makes a clicking sound must have a drive inside and vibrates one more time followed by more clicking. still black and nothing after that. I am leaving it on the charger tonight. If there is a shred of hope please share. off subject i love the similar too on the when creating a topic