Structure of soil organic matter (SOM) is a hot topic of discussion among scientific community for several decades. The mostly discussed models, among many, are polymer model and supramolecular model. While the former considers SOM as macromolecules consisting of amorphous and crystalline domains, the latter explains SOM as a physicochemical entity dominated by weak hydrophobic and H-bond interactions in the secondary level, which holds individual molecules of primary structure together. The weak forces in secondary level impart characteristic mobility of SOM. Very important consequence of this multidimensional formulation is that physicochemical structure plays a crucial role in most biogeochemical functions of SOM, apart from the chemical composition. Recently introduced concept of cation and water molecule mediated bridges between OM molecular segments (CaB and WaMB, respectively) evolved from physicochemical understanding of SOM structure. Even though several indirect evidences were produced for CaB and WaMB during last years, no clear-cut understanding of these processes has been achieved yet. Experimental difficulty due to overlapping effects of equally important CaB-governing parameters such a pH and competing cations raises huge challenge in investigating CaB-related influences. This thesis, therefore, aims to validate an experimental set-up for inducing CaB within OM structures and assessing it from various chemical and physicochemical aspects.

The method involved removal of omnipresent cations and adjustment of pH before cation addition. This helped to separate pH effects and cation effects. Based on results obtained on two different types of organic matter, it can be deduced that multivalent cations can cross-link SOM, given that functional group density of the SOM material is enough for the functional groups to be arranged in sufficient spatial proximity to each other. Physicochemical structural reorganisation during aging causes formation of more and/or stronger CaB and WaMB. As for inducing CaB directly after cation treatment, cationic size and valency were found determinant also for aging effect. A strongly cross-linked system in the beginning is less vulnerable to structural changes and undergoes aging with lower intensity, than an initially weakly cross-linked system. Responsible for the structural changes is, the inherent mobility of SOM within its physicochemical assemblage. Thus the information on structural requirement of CaB and its consequences on OM matrix rigidity will help to obtain insight into the physicochemical SOM structure. Additionally, organic matter quality (assessed by thermal analysis) and pore structure of SOM formed in a set of artificial soils showed that mineral materials are important for the chemical nature of SOM molecules, but not for the physical structure of organo-mineral associations, at least after several months of SOM development.

Furthermore, nanothermal analysis using atomic force microscopy (AFM-nTA) was implemented in soils for the first time to reveal nanoscale thermal properties and their spatial distribution in nano- and micrometer scales. This helped to identify physicochemical processes, such as disruption of WaMB, in low-organic soils, in which bulk methods fail due to their low sensitivity. Further, various types of materials constituting in soils were distinguished with high resolution by advanced application of the method, in combination with other AFM parameters. Attempts were done to identify various materials, with the usage of defined test materials. Above all, the method is potent to reveal microspatial heterogeneity on sample surfaces, which could help understanding process-relevant hotspots, for example.

This thesis thus contributes to the scientific understanding on physicochemical structural dynamics via cross-linking by cations and via nanoscale thermal properties. Direct investigation on CaB demonstrated here will potentially help making a big leap in knowledge about the interaction. The observed aging effects add well to the understanding of supramolecular consideration of SOM. By introducing nanothermal analysis to the field of soil science, it is made possible to face the problem of heterogeneity and spatial distribution of thermal characteristics. Another important achievement of AFM-nTA is that it can be used to detect physicochemical processes, which are of low intensity.


In spring 2012, five SPEA students completed a graduate-level capstone project focusing on the subject of domestic violence for Hamilton County, Indiana. The goal of this project was to report the extent of domestic violence in Hamilton County, criminal justice system response, and, finally, to research evidence-based best practices that could better direct response efforts. To determine the extent of domestic violence, data was collected from police dispatchers, Prevail - a local nonprofit organization, and the Hamilton County prosecutor's office. Data was then analyzed to provide Hamilton County officials with statistics showing the number of calls for service, arrest rates, prosecution rates, and court dispositions between January 1, 2009 and January 1, 2010. Key informant interviews were conducted with Hamilton County officials involved in response efforts including police officers, prosecutors, and victim service providers. Best practices interviews were also conducted via phone with those involved in the implementation of successful programs throughout the country which were determined from information gained through the literature review process. Overall recommendations were made such as adopting a zero tolerance policy, requiring police officers to write reports for all domestic violence calls for service, implementing new technology to track indicator crimes, and providing additional, diversified training for not only police officers, but court officials as well. The report begins by providing background information on the project and Hamilton County. This is followed by a detailed methodology outlining the data collection process. Next is a literature review on the problem of domestic violence and re-offense rates along with best practices programs. The report continues with a detailed analysis of primary and secondary data. Finally, recommendations are made for Hamilton County based on all of the information gathered from the aforementioned methodology followed by two key informant interviews.


Natural gas and oil production from stripper wells also produces water contaminated with hydrocarbons, and in most locations, salts and trace elements. The hydrocarbons are not generally present in concentrations that allow the operator to economically recover these liquids. Produced liquids, (Stripper Gas Water) which are predominantly water, present the operator with two options; purify the water to acceptable levels of contaminates, or pay for the disposal of the water. The project scope involves testing SynCoal as a sorbent to reduce the levels of contamination in stripper gas well produced water to a level that the water can be put to a productive use. Produced water is to be filtered with SynCoal, a processed sub-bituminous coal. It is expected that the surface area of and in the SynCoal would sorb the hydrocarbons and other contaminates and the effluent would be usable for agricultural purposes. Test plan anticipates using two well locations described as being disparate in the level and type of contaminates present. The loading capacity and the rate of loading for the sorbent should be quantified in field testing situations which include unregulated and widely varying liquid flow rates. This will require significant flexibility in the initial stages of the investigation. The scope of work outlined below serves as the guidelines for the testing of SynCoal carbon product as a sorbent to remove hydrocarbons and other contaminants from the produced waters of natural gas wells. A maximum ratio of 1 lb carbon to 100 lbs water treated is the initial basis for economic design. While the levels of contaminants directly impact this ratio, the ultimate economics will be dictated by the filter servicing requirements. This experimental program is intended to identify those treatment parameters that yield the best technological practice for a given set of operating conditions. The goal of this research is to determine appropriate guidelines for field trials by accurately characterizing the performance of SynCoal over a full range of operating conditions.


The long-term build-up of nutrients in agricultural fields has contributed to surface and ground water quality problems in many jurisdictions. The Ontario government has required the use of a decision support system, entitled NMAN, to develop nutrient management strategies for new or expanding livestock facilities. The NMAN software adds nutrient (N and P) sources (commercial fertilizer, manure, crop residual, grazing) and subtracts nutrients lost through crop removal and runoff to calculate the assimilative capacity on a field-by-field basis. NMAN is designed to help guide nutrient management at the farm-scale and to prevent the long-term build-up of nutrients in agricultural soils. However, success ultimately rests with the farmers' willingness to use NMAN on a continuing basis for determining nutrient application rates. While several factors are shown to influence the use agricultural decision support systems, perceived usefulness or value is key. In an effort to inform users about the NMAN software, we provide a brief description and sensitivity analysis of selected input variables. The newest version, NMAN3, is more intuitive than earlier versions, and it is easier to navigate and to modify parameters. Using a sample nutrient management strategy, we determine the sensitivity of output parameters to changes in the input variables. We primarily focus on the Phosphorus (P) Index, which measures a potential P loss from agricultural fields. The results indicate that the some parameters used in NMAN3, i.e. slope percentage, slope length, etc., need to be accurately measured, and that agency officials should be aware of these parameters during site visits and/or inspections.


This paper originates from the FP6 project "Emergence in the Loop (EMIL)" which explores the emergence of norms in artificial societies. Part of work package 3 of this project is a simulator that allows for simulation experiments in different scenarios, one of which is collaborative writing. The agents in this still prototypical implementation are able to perform certain actions, such as writing short texts, submitting them to a central collection of texts (the "encyclopaedia") or adding their texts to texts formerly prepared by other agents. At the same time they are able to comment upon others' texts, for instance checking for correct spelling, for double entries in the encyclopaedia or for plagiarisms. Findings of this kind lead to reproaching the original authors of blamable texts. Under certain conditions blamable activities are no longer performed after some time.


Animal groups in motion, examples being fish schools, bird flocks, insect swarms and mammal herds, can exhibit spectacular collective behaviour. Attempts at formalizing the basic individual behaviour that accounts for the complex dynamics of an animal group began over 50 years ago. Numerous models of these dynamics have since been published. We review this information, starting with an overview of various approaches that have arisen from mathematical, physical, and computer-modelling methods. Our focus is on individual-based models of animal groups. Individuals are assumed to exert three types of local interactions with their neighbours in these models, namely attraction, alignment, and repulsion. We review these models according to their main objectives: to compare modelled results with observational data; to analyse the influence of model parameters on simulated group properties; and to investigate group response to any change in environment, or to divergent behaviour of some of the group members.


Whether approached as a matter of executive discretion, judicial role, or individual rights, questions about security are never far removed from questions about liberty. Tradeoffs between liberty and security often seem unavoidable. Defenders of unbounded executive power argue that security relies on experts to whom citizens and courts alike must defer. But, if the tradeoff between security and liberty is to be a real weighing of the risks, costs, benefits, burdens, and consequences of various policy decisions, then who has the necessary expertise to decide on liberty? After all, to make decisions about the appropriate balance between security and liberty implies that a decision-maker be an expert not only about security, but also about liberty. Otherwise, the idea of a balanced tradeoff is empty; either citizens and courts have non-exclusive authority to decide on both, or courts must grant executive officials expansive deference on matters of both security and liberty. This Article argues that the latter proposition is untenable and that, therefore, citizens and courts must have non-exclusive authority to make decisions about both national security and individual liberty. Nowhere in American constitutional traditions and practice can we find unchecked executive authority over matters of liberty. As a consequence, we should expect institutionally allocated authority over both liberty and security. Apart from the special knowledge citizens and courts might have about particular matters of liberty, an interest in allocating authority over questions of liberty is in part justified by the harms of concentrated decision-making a polity seeks to avoid. Advocates of unbounded executive authority argue that concern over tyranny is a phobia. Against this view, this Article argues that far from emotional responses to crises, American constitutional culture disperses authority over both liberty and security as a constitutive feature of constrained political practice.


Constitutional interpretation is the activity that discovers the communicative content or linguistic meaning of the constitutional text. Constitutional construction is the activity that determines the legal effect given the text, including doctrines of constitutional law and decisions of constitutional cases or issues by judges and other officials. The interpretation-construction distinction, frequently invoked by contemporary constitutional theorists and rooted in American legal theory in the nineteenth and twentieth centuries, marks the difference between these two activities.This Article advances two central claims about constitutional construction. First, constitutional construction is ubiquitous in constitutional practice. The central warrant for this claim is conceptual: because construction is the determination of legal effect, construction always occurs when the constitutional text is applied to a particular legal case or official decision. Although some constitutional theorists may prefer to use different terminology to mark the distinction between interpretation and construction, every constitutional theorist should embrace the distinction itself, and hence should agree that construction in the stipulated sense is ubiquitous. Construction occurs in every constitutional case. The second claim is more substantive and practical. In some cases, construction can simply translate the plain meaning of the constitutional text into corresponding doctrines of constitutional law — we might call this strict construction. But in other cases, the constitutional text does not provide determinate answers to constitutional questions. For example, the text may be vague or irreducibly ambiguous. We can call this domain of constitutional underdeterminacy the construction zone. The second claim is that the construction zone is ineliminable: the actual text of the U.S. Constitution contains general, abstract, and vague provisions that require constitutional construction that goes beyond the meaning of the text for their application to concrete constitutional cases.Part I of this Article situates the idea of constitutional construction in the context of contemporary debates about originalism and among originalists. Part II argues that the interpretation-construction distinction provides conceptual clarity and answers a variety of objections to the distinction itself and the use of the terms "interpretation" and "construction" to express the distinction. Part III advances the claim that construction is ubiquitous; Part IV makes the case for the ineliminability of the construction zone. Part V discusses the relationship between constitutional construction and debates about originalism and living constitutionalism. A conclusion follows.This is the final version of this article as it appears in print.


Feel lonely? What about reading books? Book is one of the greatest friends to accompany while in your lonely time. When you have no friends and activities somewhere and sometimes, reading book can be a great choice. This is not only for spending the time, it will increase the knowledge. Of course the b=benefits to take will relate to what kind of book that you are reading. And now, we will concern you to try reading literary labyrinth as one of the reading material to finish quickly.


America has begun to censor the Internet. Defying conventional scholarly wisdom that Supreme Court precedent bars Internet censorship, federal and state governments are increasingly using indirect methods to engage in "soft" blocking of on-line material. This Article assesses these methods and makes a controversial claim: hard censorship, such as the PROTECT IP Act, is normatively preferable to indirect restrictions. It introduces a taxonomy of five censorship strategies: direct control, deputizing intermediaries, payment, pretext, and persuasion. It next makes three core claims. First, only one strategy - deputizing intermediaries - is limited significantly by current law. Government retains considerable freedom of action to employ the other methods, and has begun to do so. Second, the Article employs a process-based methodology to argue that indirect censorship strategies are less legitimate than direct regulation. Lastly, it proposes using specialized legislation if the U.S. decides to conduct Internet censorship, and sets out key components that a statute must include to be legitimate, with the goal of aligning censorship with prior restraint doctrine. It concludes by assessing how soft Internet censorship affects current scholarly debates over the state's role in shaping information on-line, sounding a skeptical note about government's potential to balance communication.


This article examines two recent developments in watershed protection. First, the growth of ecosystem services research has reframed the manner in which value accrues in natural resources. At the intersection of economics and ecology, the study of ecosystem services has supported the attribution of economic value to ecosystem processes. Second, local governments are participating quite intentionally in watershed management by identifying with particular watersheds, particular watershed features, and particular watershed functions, in ways that other entities lack the institutional capacity to do. These developments are important for watershed protection in ways not previously seen: even if they leave political boundaries intact, when local governments protect watershed functionality, they are acting to preserve natural capital, and natural capital is geographically situated in ways that defy the sanctity of political boundaries. This article addresses the importance of driving local governments to watershed planning and management by introducing the perspective of ecosystem and watershed services. Part II of this article discusses the complexity of functional watersheds and identifies watershed features that can be categorized in ecosystem services terms as the provisioning, regulating, cultural, and supporting services. By discussing watershed services, this part identifies the valuable ecosystem services in watersheds and the objectives of watershed investments. Part II furthermore explores the nature of watershed planning in the context of existing regulatory, property, and sovereignty ownership schemes for the purpose of identifying the level at which local governments are held to account for watershed investments. This part explores the notion that local governments are so grounded relative to watersheds that the task of identifying and satisfying local needs and parochial perspectives – often thought to impede sound environmental planning – should be considered a primary driver in a collaborative and developing process. Part III of this article discusses the manner in which the ecosystem services perspective illuminates particular local governance needs.


The story of The Boy in the Striped Pyjamas is very difficult to describe. Usually we give some clues about the book on the cover, but in this case we think that would spoil the reading of the book. We think it is important that you start to read without knowing what it is about. If you do start to read this book, you will go on a journey with a nine-year-old boy called Bruno. And sooner or later you will arrive with Bruno at a fence. We hope you never have to cross such a fence.


As a major scientific society, the AAAI has a responsibility for promoting its field as well as informing its members of the latest technical developments. Since the latter function is adequately performed by the several journals and conference proceedings already mentioned, the editorial committee chose to assign to AI Magazine the task of providing AAAI members and the public as well with a broader perspective on the research activities within AI. The approach we intend to take includes publishing informative expository and survey articles designed not so much for those working within a particular problem domain, but for those outside it who would like to gain a better understanding of the issues and methods currently being studied without having to cull all the technical literature.


Flying robots that can locomote efficiently in GPS‐denied cluttered environments have many applications, such as in search and rescue scenarios. However, dealing with the high amount of obstacles inherent to such environments is a major challenge for flying vehicles. Conventional flying platforms cannot afford to collide with obstacles, as the disturbance from the impact may provoke a crash to the ground, especially when friction forces generate torques affecting the attitude of the platform. We propose a concept of resilient flying robots capable of colliding into obstacles without compromising their flight stability. Such platforms present great advantages over existing robots as they are capable of robust flight in cluttered environments without the need for complex sense and avoid strategies or three‐dimensional mapping of the environment. We propose a design comprising an inner frame equipped with conventional propulsion and stabilization systems enclosed in a protective cage that can rotate passively thanks to a three‐axis gimbal system, which reduces the impact of friction forces on the attitude of the inner frame. After addressing important design considerations thanks to a collision model and validation experiments, we present a proof‐of‐concept platform, named GimBall, capable of flying in various cluttered environments. Field experiments demonstrate the robot's ability to fly fully autonomously through a forest while experiencing multiple collisions.


Critics have generally agreed that of all of Shakespeare's sonnets cvii offers the most hope for dating by internal evidence. It runs: Not mine own fears, nor the propehtic soul Of the wide world dreaming on things to come, Can yet the lease of my true love control, Supposed as forfeit to a confined doom. The mortal moon hath her eclipse endured, And the sad augurs mock their own presage; Incertainties now crown themselves assured, And peace proclaims olives of endless age. Now with the drops of this most balmy time My love looks fresh, and Death to me subscribes, Since spite of him I'll live in this poor rhyme, While he insults o'er dull and speechless tribes; And thou in this shall find thy monument, When tyrants crests and tombs of brass are spent.


We evolved to eat berries rather than bagels, to live in mud huts rather than condos, to sprint barefoot rather than play football-or did we? Are our bodies and brains truly at odds with modern life? Although it may seem as though we have barely had time to shed our hunter-gatherer legacy, biologist Marlene Zuk reveals that the story is not so simple. Popular theories about how our ancestors lived-and why we should emulate them-are often based on speculation, not scientific evidence. Armed with a razor-sharp wit and brilliant, eye-opening research, Zuk takes us to the cutting edge of biology to show that evolution can work much faster than was previously realized, meaning that we are not biologically the same as our caveman ancestors. Contrary to what the glossy magazines would have us believe, we do not enjoy potato chips because they crunch just like the insects our forebears snacked on. And women don't go into shoe-shopping frenzies because their prehistoric foremothers gathered resources for their clans. As Zuk compellingly argues, such beliefs incorrectly assume that we're stuck-finished evolving-and have been for tens of thousands of years. She draws on fascinating evidence that examines everything from adults' ability to drink milk to the texture of our ear wax to show that we've actually never stopped evolving. Our nostalgic visions of an ideal evolutionary past in which we ate, lived, and reproduced as we were "meant to" fail to recognize that we were never perfectly suited to our environment. Evolution is about change, and every organism is full of trade-offs. From debunking the caveman diet to unraveling gender stereotypes, Zuk delivers an engrossing analysis of widespread paleofantasies and the scientific evidence that undermines them, all the while broadening our understanding of our origins and what they can really tell us about our present and our future.


This thesis consists of five chapters: Chapter 1 contains the basics of the theory and is essential for the rest of the thesis. Chapters 2-5 are to a large extent independent of each other and can be read separately. - Chapter 1: Foundations of tropical intersection theory In this first chapter we set up the foundations of a tropical intersection theory covering many concepts and tools of its counterpart in algebraic geometry such as affine tropical cycles, Cartier divisors, morphisms of tropical cycles, pull-backs of Cartier divisors, push-forwards of cycles and an intersection product of Cartier divisors and cycles. Afterwards, we generalize these concepts to abstract tropical cycles and introduce a concept of rational equivalence. Finally, we set up an intersection product of cycles and prove that every cycle is rationally equivalent to some affine cycle in the special case that our ambient cycle is R^n. We use this result to show that rational and numerical equivalence agree in this case and prove a tropical Bezout's theorem. - Chapter 2: Tropical cycles with real slopes and numerical equivalence In this chapter we generalize our definitions of tropical cycles to polyhedral complexes with non-rational slopes. We use this new definition to show that if our ambient cycle is a fan then every subcycle is numerically equivalent to some affine cycle. Finally, we restrict ourselves to cycles in R^n that are "generic" in some sense and study the concept of numerical equivalence in more detail. - Chapter 3: Tropical intersection products on smooth varieties We define an intersection product of tropical cycles on tropical linear spaces L^n_k and on other, related fans. Then, we use this result to obtain an intersection product of cycles on any "smooth" tropical variety. Finally, we use the intersection product to introduce a concept of pull-backs of cycles along morphisms of smooth tropical varieties and prove that this pull-back has all expected properties. - Chapter 4: Weil and Cartier divisors under tropical modifications First, we introduce "modifications" and "contractions" and study their basic properties. After that, we prove that under some further assumptions a one-to-one correspondence of Weil and Cartier divisors is preserved by modifications. In particular we can prove that on any smooth tropical variety we have a one-to-one correspondence of Weil and Cartier divisors. - Chapter 5: Chern classes of tropical vector bundles We give definitions of tropical vector bundles and rational sections of tropical vector bundles. We use these rational sections to define the Chern classes of such a tropical vector bundle. Moreover, we prove that these Chern classes have all expected properties. Finally, we classify all tropical vector bundles on an elliptic curve up to isomorphisms.


In 1963, President Kennedy outlined a federal program designed to reduce by half the number of persons in custody in mental hospitals. What followed was the biggest deinstitutionalization this country has ever seen. The historical record is complex and the contributing factors are several, but one simple fact remains: This country has deinstitutionalized before. As we think about reducing mass incarceration today, it may be useful to recall some lessons from the past. After tracing the historical background, this essay explores three potential avenues to reduce mass incarceration: First, improving mental health treatment to inmates and exploring the increased use of medication, on a voluntary basis, as an alternative to incarceration; in a similar vein, increasing the use of GPS monitoring and other biometric monitoring, and moving toward the legalization of lesser controlled substances. Second, encouraging federal leadership to create funding incentives for diversionary programs that would give states a financial motive to move prisoners out of the penitentiary and into community-based programs. Third, encouraging impact litigation of prison overcrowding, as well as documentaries of prison life, as a way to influence the public perception of prisoners. With regard to each of these strategies, however, it is crucial to avoid the further racialization of the prison population and merely transferring prisoners to equally problematic institutions.


Virtual property, or that property which exists only in the intangible world of cyberspace, is of growing importance. Millions of people use some form of virtual property every day, be it an e-mail account, a blog, or a Facebook profile. Billions of dollars are spent to acquire property in the virtual world. And the economic and social impact of virtual property is only likely to increase at light year speed. As the importance of virtual property continues to rise, laws pertaining to virtual property must similarly develop. Among the emerging legal issues yet unaddressed by scholarship or jurisprudence is how community property regimes will respond to virtual community (or separate) property. Because the acquisition of virtual property such as websites, domain names, e-mail accounts, and even Facebook pages, create a property interest, in the nine community property states, community property laws impact what rights spouses have in such property. Thus, spouses are on the brink of litigating issues such as whether a Uniform Resource Locator (URL) is community or separate property, whether a website generates an increase in separate property, whether e-mail contacts are profits, and whether Facebook friends create goodwill. Community property jurisdictions must be prepared to quickly adapt to the reality of virtual property if the regimes wish to avoid being left in the wake of cyberspace. To aid courts in their impending task of considering virtual property in a community setting, this Article examines how different forms of virtual property should be classified in community property regimes. After explaining the classification scheme within community property jurisdictions, the Article details examples of virtual property likely to be present in modern couples' lives, and considers how the identified examples of virtual property should be classified.


How is it that between 1922 and 1934, James Joyce's Ulysses, considered the greatest English language novel of the twentieth century, could not get published in the United States without risk of prosecution and jail? How did American law get its ideas about obscenity and censorship so wrong? This Article closely analyzes the facts and the reasoning, or lack of reasoning, in R. v. Hicklin, the Queen's Bench decision of 1868 whose throwaway single sentence defining obscenity was reflexively adopted by American courts and became the greatest legal impediment to artistic freedom in the United States for nearly a century. The Article traces Hicklin's influence in the United States through the first third of the twentieth century. Using archival and other sources, it then closely examines the first court test of a part of Ulysses, in New York in 1920-21, a case that might have been won, but ended in the obscenity convictions of two women who published an obscure literary magazine. Their convictions impeded publication of the book until Morris Ernst's brilliant legal strategy gave his client, Random House, confidence that it could publish Ulysses in the United States without fear of prosecution. While the district court decision in Ernst's favor is rightly applauded for freeing Ulysses, the judge's reasoning does not resemble anything we can recognize as law. It is a decision for one book only. Even Augustus Hand's opinion for the Second Circuit affirming Ernst's victory, which cousin Learned joined and which contains the seeds of modern obscenity doctrine, required some jurisprudential sleight of hand to escape unfavorable circuit and Supreme Court precedent. The story from Hicklin to Ulysses II is both riveting in itself and as legal and cultural history. But it is also a lesson about harm done when government interferes with the intellectual and personal autonomy of individuals.


The prostate cancer screening tests that have become an annual ritual for many men don't appear to reduce deaths from the disease among those with a limited life-expectancy, according to early results of a major U.S. study involving 75,000 men. Results released today from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial show that six years of aggressive, annual screening for prostate cancer led to more diagnoses of prostate tumors but not to fewer deaths from the disease. The study, led by researchers at Washington University School of Medicine in St. Louis and conducted at 10 sites, appeared online March 18, 2009 in the New England Journal of Medicine (and in the journal's print edition on March 26). "The important message is that for men with a life expectancy of seven to 10 years or less, it is probably not necessary to be screened for prostate cancer," says the study's lead author and principal investigator Gerald Andriole, M.D., chief urologic surgeon at the Siteman Cancer Center at Washington University School of Medicine and Barnes-Jewish Hospital. But it's too soon, he added, to make broad screening recommendations for all men based on the study's initial findings. "So far, only a minority of men enrolled in the PLCO study have died, so it may be premature to make generalizations about the ultimate results of the trial," he says. "We don't have enough data yet about the youngest men in the study - those in their 50s - and it may be that over time, we will, in fact, see a benefit from screening." Nearly 6,400 men are enrolled in the study at Washington University. Robert Grubb III, M.D., assistant professor of surgery, is a collaborator and the study's second author. The PLCO trial began in 1992 with funding from the National Cancer Institute and was designed to determine whether prostate cancer screening reduces deaths from the disease. It involves men ages 55 to 74 who received either annual PSA blood tests and digital rectal exams or "routine care," meaning they had the screening tests only if their physicians recommended them. After seven to 10 years of follow up, deaths from prostate cancer were very low in both groups and did not differ significantly between the groups. Health guidelines issued last year by the U.S. Preventive Services Task Force recommend against prostate cancer screening for men age 75 or older and concluded there is insufficient evidence to assess the balance of benefits and harms of prostate cancer screening in men younger than 75. However, the American Urological Association and the American Cancer Society recommend annual prostate cancer screening tests beginning at age 50 for most men. More than 186,000 U.S. men will be diagnosed with prostate cancer this year, and nearly 29,000 will die from the disease, according to the National Cancer Institute. PSA blood tests, introduced in 1988, have increasingly been used as a screening tool for prostate cancer, despite a lack of evidence showing they reduce death rates from disease. The controversy over prostate cancer screening has arisen because most men who undergo a biopsy for an abnormal PSA test do not have prostate cancer. For those who have cancer, the tumors generally grow so slowly that most men die of other causes. Furthermore, prostate cancer treatment can result in incontinence and impotence. However, some tumors can be aggressive, and the difficulty has been distinguishing aggressive cancers from those that are slow growing. "We definitely need to find better ways to detect and treat aggressive tumors, those that are truly life-threatening, so that men with slow-growing tumors can avoid unnecessary treatments," says Andriole. Today's results are the first to detail death rates from prostate cancer among men in the PLCO study and are being released to coincide with the presentation of the data at the European Association of Urology meeting in Stockholm, Sweden. The PLCO data are being made public now because the study's Data and Safety Monitoring Board, an independent review committee that meets every six months, saw a continuing lack of evidence that screening reduces deaths due to prostate cancer as well as the suggestion that screening may cause men to be treated unnecessarily. The PLCO investigators will continue to follow patients for several more years to see whether annual screening eventually reduces prostate cancer deaths. The trial involved 76,693 men, who were randomly assigned to receive either annual PSA blood tests for six years and digital rectal exams for four years or routine care, which included physical checkups but no mandate for annual prostate cancer screening. The new report includes data for all participants seven years after they joined the trial and for 67 percent of participants 10 years after they joined the trial. At seven years, there were 22 percent more prostate cancer diagnoses in the men screened annually (2,820 men in the screening group vs. 2,322 in the routine-care group). This trend has continued in data collected up to 10 years (currently there are 17 percent more prostate cancer diagnoses in the screening group). Deaths from prostate cancer did not differ significantly between the groups. Seven years after the start of screening, there were 50 deaths from prostate cancer in the screening group and 44 deaths in the routine-care group. Ten years after the start of screening, there were 92 prostate cancer deaths in the screening group and 82 in the routine-care group. "My recommendation is that, for now, men with a life expectancy of more than seven to 10 years continue to be screened for prostate cancer," says Andriole. "On the other hand, screening is probably not necessary for elderly men and men with significant health issues. These men should have a conversation with their doctors to make an individual decision about whether they want to be screened, because clearly there can be harmful side effects related to treatment, while for these men, there has been no demonstration that screening will prolong their lives." Of the men who received annual screening, 85 percent had PSA tests and 86 percent had digital rectal exams. Men in the routine-care arm sometimes had prostate cancer screening tests: PSA screening ranged from 40 percent of men at the beginning of the study to 52 percent of men by the last screening year, and screening with rectal exams ranged from 41 percent initially to 46 percent by the last screening year. The exam involves a doctor inserting a lubricated, gloved finger into the rectum to feel for anything that is not normal. Men were referred for follow up testing for prostate cancer if their PSA level was higher than 4.0 ng/ml or if the rectal exam was abnormal. The researchers noted that the vast majority of men in both groups who developed prostate cancer were diagnosed with stage II disease (out of IV). The number of later-stage cases was similar in the two groups. However, men in the routine-care group had more aggressive tumors (Gleason score 8-10). The reduced number of men with prostate cancer with a Gleason score of 8-10 in the intervention group may eventually lead to a mortality difference, but data analyzed so far have not shown such a benefit. Additionally, men in both groups received similar treatments for their disease, which was not dictated by being a participant in the PLCO. Another study reported in this same online issue of the NEJM is the large European Randomized Trial of Screening for Prostate Cancer (ERSPC), which shows a 20 percent reduction in the rate of death from prostate cancer but with a high risk of overdiagnosis. In the ERSPC, unlike the PLCO trial, men were referred for follow-up testing if their PSA level was 3.0 ng/mL or higher and were also screened, on average, every four years as opposed to annually in the PLCO. Lowering the threshold for what is considered an abnormal PSA to 3.0 ng/ml is likely to diagnose more tumors but not necessarily identify those that are more likely to be aggressive, Andriole says. Contact: Caroline Arbanas email@example.com (314) 286-0109


For decades, scholars and courts have debated whether the Anti-Drug Abuse Act of 1986 discriminates against African Americans by imposing far stiffer punishments for trafficking in crack cocaine than in its powdered form. The academy has generally concluded that the federal crack cocaine sentencing laws are racially discriminatory, while the federal courts have almost uniformly rejected the same argument. Three years ago Congress, via the Fair Sentencing Act of 2010, addressed the issue by reducing, without eliminating, the sentencing disparity. Recently, the U.S. Court of Appeals for the Sixth Circuit in United States v. Blewett, 719 F.3d 482 (6th Cir. 2013), concluded that the 2010 statute would be unconstitutional if it were not applied retroactively. The Blewett case forces this debate back into the political arena. The Sixth Circuit misapplied equal protection law. Rather than ask whether Congress refused to apply the Fair Sentencing Act retroactively for a discriminatory purpose, the court concluded that Congress's decision to adopt a prospective-only statute was tantamount to readoption of Jim Crow. Settled law, however, requires proof of discriminatory intent. Moreover, Congress's refusal to adopt retroactive legislation cannot violate the Due Process Clause. The clause applies only to positive law, so Congress cannot violate the clause by not enacting legislation. Finally, the Sixth Circuit failed to consider the effect of strict enforcement of the drug laws on the innocent residents of communities where crack trafficking occurs. It may be unwise to continue to imprison crack offenders for the full length of their prison terms imposed under the strict provisions of a now-amended law, but a mistaken decision is not invariably an unconstitutional one.