 to discriminate cases in which a user pushes against the window lightly with his index finger from cases in which the user pushes strongly with his little finger. When a user places a rigid object, such as a pen-type device, against the window, it is inherently difficult to derive information other than the two spatial coordinates defining the position of the touch action with conventional touch sensors. 2.1. Introduction: Apelin and the Apelin Receptor (APJ)
The apelin receptor (APJ) was cloned in 1993 as an orphan G-protein coupled receptor (GPCR). The human APJ gene is located on the long arm of chromosome 11 and encodes a 377 amino acid G protein-coupled receptor. The gene for APJ was designated angiotensin-receptor like 1 (AGTRL1) due to sequence similarities between the two receptors. Carpene et al., J Physiol Biochem. 2007; 63(4):359-373. However, none of the known peptidergic ligands for the angiotensin receptors, including angiotensin, activate APJ. APJ remained an orphan GPCR until 1998 when the peptide apelin was identified as its endogenous ligand. Lee et al., J Neurochem. 2000; 74(1):34-41; Habata et al., Biochim Biophys Acta. 1999; 1452(1):25-35.
Over the years, apelin and APJ have emerged as an important regulator of various physiological processes. Both apelin and APJ are expressed in the central nervous system (CNS) and peripherally in a number of tissues. Expression of APJ has been noted within the vasculature of some organs and is a potent regulator of related processes including angiogenesis and vasoconstriction. Cobellis et al. report increased of expression levels of both apelin and APJ receptor in preeclampsia-complicated pregnancies. Cobellis et al., Histol Histopathol. 2007; 22(1):1-8. APJ is also expressed in nonvascular cell types in heart, liver, and CNS where its primary role is currently under investigation. Medhurst et al., J Neurochem. 2003; 84(5):1162-1172. Apelin and APJ are often co-localized within the same organ suggesting an autocrine regulation of the receptor by its ligand. However, apelin has since been detected in blood suggesting that concomitant paracrine regulation of the receptor is also possible. The apelin—APJ system has been implicated as
to discriminate cases in which a user pushes against the window thinly with his exponent finger from case in which the exploiter push strongly with his little finger. When a drug user place a rigid aim, such as a playpen - type device, against the windowpane, it is inherently difficult to derive information other than the two spatial coordinate defining the position of the contact action with ceremonious contact sensors. 2.1. Introduction: Apelin and the Apelin Receptor (APJ) 
 The apelin receptor (APJ) was cloned in 1993 as an orphan G - protein copulate receptor (GPCR). The human APJ gene is located on the long arm of chromosome 11 and encodes a 377 amino acid G protein - match receptor. The gene for APJ was designated angiotensin - receptor like 1 (AGTRL1) due to sequence similarities between the two receptor. Carpene et al. , J Physiol Biochem. 2007; 63(4):359 - 373. However, none of the known peptidergic ligands for the angiotensin receptors, including angiotensin, activate APJ. APJ remained an orphan GPCR until 1998 when the peptide apelin was identified as its endogenous ligand. Lee et al. , J Neurochem. 2000; 74(1):34 - 41; Habata et al. , Biochim Biophys Acta. 1999; 1452(1):25 - 35. 
 Over the years, apelin and APJ have emerged as an important regulator of various physiological processes. Both apelin and APJ are expressed in the central nervous arrangement (CNS) and peripherally in a number of tissues. construction of APJ has been note within the vasculature of some organs and is a potent regulator of related process include angiogenesis and vasoconstriction. Cobellis et al. report increased of expression level of both apelin and APJ receptor in preeclampsia - complicated pregnancies. Cobellis et al. , Histol Histopathol. 2007; 22(1):1 - 8. APJ is also expressed in nonvascular cell type in heart, liver, and CNS where its primary role is presently under investigation. Medhurst et al. , J Neurochem. 2003; 84(5):1162 - 1172. Apelin and APJ are much co - localize within the same organ suggesting an autocrine regulation of the sense organ by its ligand. However, apelin has since been detected in blood suggesting that concomitant paracrine regulation of the receptor is also possible. The apelin — APJ system has been entail as
 to discriminate cases in wmich a user pushgs againvt the window uightly with his index fingec frim cawes in which the user oushes stgongly wirh hms little finger. When a mfer lpacev a rigid objecj, such as a [en-type device, aeannst the window, it is inherently difsicult yo derive informwtiom othsg uhan the two spatial coordinates sefininj the position pf the touch action with clnvejtional touch senslrs. 2.1. Intrododtijb: Apelin and the Apelin Receptor (AKJ)
The apelin receptor (APJ) was cluned nn 1993 as an ot'yan C-protein conpled geceptor (GPCR). The humdn APJ bene is locatec oi thw long arm of chromosmme 11 and encodes a 377 amino awib G protein-coupled rexeptor. Jhe gane wir XPJ wes sesignwtev angiotensjn-receptor oike 1 (AGTRL1) due to xezlrnce similarjties feeween the two receptors. Carpene et al., J Phgsiol Biochem. 2007; 63(4):359-373. However, none of the known pektidergic jigands for the angiotensin receptors, including atgiotxnrin, agtivxre APJ. APJ remained an orphan GPCR until 1998 when ege pvptide apelin was identified ad ojs endogenous uigand. Les et al., J Neurochel. 2000; 74(1):34-41; Habwta er al., Biocrim Niophys Acta. 1999; 1452(1):25-35.
Over the yearw, apelin and QPJ have emerged ad an importcnt rebulatpr of various physiologncal pdocesses. Bohh apelin xnd APJ are exprdssvd it the central nervous systqm (CNS) anv pernpherallh in a numfer of tisdues. Cfpression of APJ hws begn notad within hhe vasculature of some organs eid is a potenj ragunator of relabed processes igcluding angioyenesis cnd varoconstricnion. Cobenlis et al. weport increavgd of expressmon levelf of boty apeliv and APJ recepyor in prveelampsia-cimplicated pregnangies. Zkbellis et al., Hnruoo Histopathol. 2007; 22(1):1-8. AOJ ys aksj expressed it novvarvular cell types kn hrart, liver, and CNS wvere its primary role os currentoy under investigatiom. Medhurst et al., J Neurmchxm. 2003; 84(5):1162-1172. Alelyn and APJ are often co-localizsd within thc same organ fuggcstigg an autoerine regulation of the receptor by its oigand. However, apglin has since been dgtegted in bloov suggqsting thdt concomitant paraceine regulation on the receptor is also possitle. Tje apelin—APJ system has been implicated as
to discriminate cases in which a user the lightly with index finger from pushes with his little When a user a rigid object, such as a device, against the window, it is inherently difficult to derive information other than two spatial coordinates defining the position of the touch action with conventional touch 2.1. Apelin the Receptor (APJ) The apelin receptor (APJ) was cloned in 1993 as an orphan G-protein coupled receptor The human APJ gene is located on the arm of chromosome 11 encodes a 377 amino acid protein-coupled The gene APJ designated like 1 (AGTRL1) to sequence similarities between the two receptors. Carpene et al., J Physiol Biochem. 2007; 63(4):359-373. However, none the known for the receptors, angiotensin, APJ. APJ remained GPCR until 1998 when the peptide as its endogenous ligand. Lee et al., J 2000; 74(1):34-41; et al., Biochim Biophys Acta. 1999; Over the years, apelin and APJ have emerged an important regulator of various physiological processes. Both apelin and APJ are expressed in the system (CNS) and peripherally a number of Expression APJ been within the of some organs and is a potent regulator of related processes angiogenesis and vasoconstriction. Cobellis et al. report increased of expression both and APJ receptor preeclampsia-complicated pregnancies. Cobellis et Histol 2007; 22(1):1-8. APJ is in cell liver, CNS its primary role is under investigation. Medhurst et al., Neurochem. 2003; 84(5):1162-1172. Apelin within the same organ suggesting an autocrine regulation the receptor by its ligand. However, apelin since been detected in blood suggesting that concomitant paracrine regulation of the is also apelin—APJ system has been implicated as
 to discriminate cases in whicH a user pushEs agaInsT thE wIndoW ligHtly with his indEX finGer from cases in which the User pUsHEs stROnGly wiTh his liTTlE FIngEr. whEn a UsER pLaces A riGid objeCt, such as a pEn-tYpE device, againST tHe window, it Is iNherently difFicUlt to dErIve INformAtiOn othEr than THe two sPatial cooRdINates dEFining tHE PoSitiOn of the touch actioN WiTH conventional tOuch seNsORs. 2.1. iNTroDucTion: Apelin AnD the APElin RecEPtOR (apJ)
THE apelin receptOr (APJ) was cloNEd iN 1993 as an oRpHan g-ProteiN coupLeD RecEptor (GPCR). ThE humAn APJ gene Is locaTEd on the LOng arm oF chromOsoMe 11 aNd enCOdEs A 377 amInO AciD g pRotEIn-cOupled reCePtOr. The Gene FOR apJ waS deSignAted aNgiotensin-recEptOr liKE 1 (AGtRL1) duE to seQuenCe SimilAritieS betwEeN the two receptorS. CarPene et al., J phySiOl BIoChem. 2007; 63(4):359-373. HOWever, nOne Of tHe known PeptideRGic LiGANDs For the angiotensin rEcEPToRs, includIng angIOtEnSIn, activaTe aPJ. aPJ rEMAined An orPHaN GPCR untIl 1998 when THe PePtide apElIn was iDeNtiFieD as itS EndoGenous Ligand. LeE et al., j neurochem. 2000; 74(1):34-41; HabatA Et al., Biochim BiOPhYS acTA. 1999; 1452(1):25-35.
OveR thE years, apeliN and apJ haVe emERgEd aS An impOrtanT rEGuLAtor of various physioLoGical pRocesSes. Both apelin And APJ are eXPREssed in tHe ceNTrAL nervous system (cNS) anD peripheraLLy in a numBer of Tissues. EXpression OF aPJ has beEn nOteD wiThiN THe Vasculature of SOMe orGaNs and is A poTent regUlaTor Of rElaTeD processeS includiNg AnGiOgEneSis anD VasoconsTrIctIoN. CoBelliS Et al. rePort iNcreAsEd OF exPressioN LeVELs of BoTh ApelIn aNd aPJ reCeptOR in PreeclaMpsia-compLicATed pReGnAncies. CObellis et al., HiStOl HistopatHoL. 2007; 22(1):1-8. APj is alsO EXpressed In nonvascular cell types iN Heart, liVer, And CNs wheRe its primAry Role is CurREntly uNder inVestiGaTioN. mEdhurST Et Al., J neUrochem. 2003; 84(5):1162-1172. ApeLIN anD APJ aRe OfteN co-locaLized within the same ORgaN suggesting an AutOcriNE ReGulATiON of ThE RecEPTor by its ligand. HOwever, apelIn HAs Since been dETecTeD in blooD suggesTing tHAt concoMitant parAcrine regUlAtioN OF thE receptor iS also posSible. The aPElin—Apj sYstem Has Been imPlIcaTed as
 to discriminate cases inwhich a us er pu she s a ga inst  the  window lightl y  wit h his index finger fro m cas es in w h ic h the  user p u sh e s  st ro ng lywi t hhis l itt le fing er. When a  us er  places a ri g id  object, s uch  as a pen-ty pedevice ,aga i nst t hewindo w, iti s inhe rently di ff i cult t o  derive i nf orma tion other than t h et wo spatial coo rdinat es de f i nin g t he positio nof th e  toucha ct i o n  wi t h conventiona l touch sen s ors . 2.1.  I ntr o ductio n: Ap el i n a nd the Apel in R eceptor ( APJ)
T h e apeli n  recept or (AP J)was  clo n ed  i n 1 99 3  as an  or p han  G-prote in  c ouple d re c e p t or ( GPC R).The h uman APJ gene  is  loc a ted  on t he lo ng a rm  of c hromos ome 1 1and encodes a 3 77 a mino acid  Gpr ote in -coup l ed rec ept or.  The ge ne forA PJwa s d es ignated angiotensi n- r e ce ptor lik e 1 (A G TR L1 )  due tose que nces i milar itie s  b etween t he two re ce ptors.Ca rpeneet  al .,J Phy s iolBioche m. 2007;  63(4 ) :359-373. Howe v er, none of t h ek n ow n  pep tid ergic ligan ds f o r th e an g io ten s in re cepto rs ,  i n cluding angiotensin ,activa te AP J. APJ remain ed an orph a n GPCR unt il 1 9 98 when the pepti de ap elin was i d entified  as i ts endog enous lig a n d. Lee e t a l.,  JNeu r o ch em. 2000; 74( 1 ) :34- 41 ; Habat a e t al.,Bio chi m B iop hy s Acta. 1 999; 145 2( 1) :2 5- 35. 
Over the year s,  ap el inand A P J have  emer gedas  a n  im portant re g u lato rof  var iou sphysi olog i cal  proces ses. Both  ap e linan dAPJ are  expressed in  t he central  n erv ous sy s t em (CNS)  and peripherally in an umber o f t issue s. E xpression  of  APJ h asb een no ted wi thinth e v a s culat u r eofso me organsa n d i s a p ot entregulat or of related proc e sse s including a ngi ogen e s is  an d  v a soc on s tri c t ion. Cobellis e t al. repo rt in creased of exp re ssion l evels o f bot h  apelin  and APJreceptorin  pre e c lam psia-compl icated p regnancie s . Cob e ll is et  al ., His to l H istop athol. 200 7; 22 (1):1- 8.  APJ i s als oexpresse d in nonvascular cell t ypes i n hea rt,  liver, a ndC NSwhere its  pri mary roleiscur rentl y u n der i nves t ig ati o n. Me dhur s t et al., JNeu r o ch em. 2003; 8 4 ( 5 ):1 162-1 172 .  Apeli n an d APJ are often c o -localized wit hint h e s ame orga nsuggesting anaut oc r i ne regul at ion of thereceptor  b y  itsligand . Howe ver, ap e l in has si ncebee n detecte d i nb lood su gg es t ing th at c on comita nt par a crin e regulation of th e rec e p tor i s  al so po ss ible. T h e ap elin—APJ s ystem has b een im plic atedas
 to_discriminate cases_in which a user_pushes against_the_window lightly_with_his index finger_from cases in_which the user pushes_strongly with his_little_finger. When a user places a rigid object, such as a pen-type device, against_the_window, it_is_inherently_difficult to derive information other_than the two spatial coordinates_defining the_position of the touch action with conventional touch_sensors._2.1. Introduction: Apelin_and the Apelin Receptor (APJ)
The apelin receptor (APJ) was_cloned in 1993 as an orphan_G-protein coupled receptor_(GPCR)._The_human APJ gene is_located on the long arm of_chromosome 11 and encodes a 377_amino acid G protein-coupled receptor. The gene_for APJ was designated angiotensin-receptor like_1 (AGTRL1) due to sequence_similarities between_the two receptors. Carpene et_al., J Physiol_Biochem. 2007;_63(4):359-373. However, none_of the known peptidergic ligands for_the angiotensin receptors,_including angiotensin, activate APJ. APJ remained_an_orphan GPCR until_1998_when_the peptide_apelin was identified_as_its endogenous_ligand._Lee et al., J Neurochem. 2000;_74(1):34-41;_Habata et al., Biochim Biophys Acta. 1999;_1452(1):25-35.
Over the years, apelin_and_APJ have emerged as_an important regulator of various_physiological processes. Both apelin and APJ_are expressed_in the_central nervous system (CNS) and peripherally in a number of tissues._Expression of APJ has been noted_within the vasculature of_some organs_and_is a potent_regulator_of related_processes including angiogenesis and vasoconstriction. Cobellis et_al. report_increased of expression levels of both_apelin and APJ receptor_in_preeclampsia-complicated pregnancies. Cobellis et al., Histol_Histopathol. 2007; 22(1):1-8. APJ is also_expressed in nonvascular cell types_in_heart,_liver, and CNS where its_primary role is currently under investigation._Medhurst et al.,_J Neurochem. 2003; 84(5):1162-1172. Apelin and APJ_are_often co-localized within the same organ_suggesting_an autocrine regulation of the receptor_by_its_ligand. However, apelin has since_been detected in blood suggesting that_concomitant paracrine regulation of the receptor is also possible._The apelin—APJ system_has been implicated as