Sample records for na falange proximal

  1. Ionic regulation of Na absorption in proximal colon: cation inhibition of electroneutral Na absorption

    SciTech Connect

    Sellin, J.H.; De Soignie, R.

    1987-01-01

    Active Na absorption (J/sub net//sup NA/) in rabbit proximal colon in vitro is paradoxically stimulated as (Na) in the bathing media is lowered with constant osmolarity. J/sub m..-->..s//sup Na/ increases almost linearly from 0 to 50 mM (Na)/sub 0/ but then plateaus and actually decreases from 50 to 140 mM (Na)/sub 0/, consistent with inhibition of an active transport process. Both lithium and Na are equally effective inhibitors of J/sub net//sup Na/, whereas choline and mannitol do not block the high rate of J/sub net//sup Na/ observed in decreased (Na)/sub 0/. Either gluconate or proprionate replacement of Cl inhibits J/sub net//sup Na/. J/sub net//sup Na/ at lowered (Na)/sub 0/ is electrically silent and is accompanied by increased Cl absorption; it is inhibited by 10/sup -3/ M amiloride and 10/sup -3/ theophylline but not by 10/sup -4/ M bumetanide. Epinephrine is equally effective at stimulating Na absorption at 50 and 140 mM (Na). Na gradient experiments are consistent with a predominantly serosal effect of the decreased (Na)/sub 0/. These results suggest that 1) Na absorption in rabbit proximal colon in vitro is stimulated by decreased (Na); 2) the effect is cation specific, both Na and Li blocking the stimulatory effect; 3) the transport is mediated by Na-H exchange and is Cl dependent but 4) is under different regulatory mechanisms than the epinephrine-sensitive Na-Cl cotransport previously described in proximal colon. Under the appropriate conditions, proximal colon absorbs Na extremely efficiently. Na-H exchange in this epithelium is cation inhibitable, either directly or by a secondary regulatory process.

  2. Ionic regulation of Na absorption in proximal colon: cation inhibition of electroneutral Na absorption

    Microsoft Academic Search

    J. H. Sellin; R. De Soignie

    1987-01-01

    Active Na absorption (J\\/sub net\\/\\/sup NA\\/) in rabbit proximal colon in vitro is paradoxically stimulated as (Na) in the bathing media is lowered with constant osmolarity. J\\/sub m..-->..s\\/\\/sup Na\\/ increases almost linearly from 0 to 50 mM (Na)â but then plateaus and actually decreases from 50 to 140 mM (Na)â, consistent with inhibition of an active transport process. Both lithium

  3. Adenosine, type 1 receptors: role in proximal tubule Na+ reabsorption

    PubMed Central

    Welch, William J

    2015-01-01

    Adenosine type 1 receptor (A1-AR) antagonists induce diuresis and natriuresis in experimental animals and humans. Much of this effect is due to inhibition of A1-ARs in the proximal tubule, which is responsible for 60–70% of the reabsorption of filtered Na+ and fluid. Intratubular application of receptor antagonists indicates that A1-AR mediates a portion of Na+ uptake in PT and PT cells, via multiple transport systems, including Na+/H+ exchanger-3 (NHE3), Na+/PO4? co-transporter and Na+-dependent glucose transporter, SGLT. Renal microperfusion and recollection studies have shown that fluid reabsorption is reduced by A1-AR antagonists and is lower in A1-AR KO mice., compared to WT mice. Absolute proximal reabsorption (APR) measured by free-flow micropuncture is equivocal, with studies that show either lower APR or similar APR in A1-AR KO mice, compared to WT mice. Inhibition of A1-ARs lowers elevated blood pressure in models of salt-sensitive hypertension, partially due to their effects in the proximal tubule. PMID:25345761

  4. ANP inhibits Na+-H+ antiport in proximal tubular brush border membrane: Role of dopamine

    Microsoft Academic Search

    Joseph Winaver; John C Burnett; Gertrude M Tyce; Thomas P Dousa

    1990-01-01

    ANP inhibits Na+-H+ antiport in proximal tubular brush border membrane: Role of dopamine.2 Infusion of ANP to rats results in an inhibition of Na+-H+ antiport and Na+-Pi symport in brush border membrane vesicles (BBMV) prepared from kidneys of these animals (J Clin Invest 75:1983). iln the present study we investigated the intrarenal mechanism by which infused ANP elicits these changes

  5. Regulation of NaCl absorption in rabbit proximal colon in vitro

    Microsoft Academic Search

    J. H. Sellin; R. De Siognie

    1987-01-01

    Ion transport in rabbit proximal colon (PC) in vitro is dominated by a Na-Cl cotransport system stimulated by epinephrine. To further characterize the regulation of Na-Cl transport, the authors tested the effects of specific adrenergic agonists on ion fluxes under short-circuit conditions. Additionally, they tested the effects of the transport inhibitors bumetanide, furosemide, and 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS). Basal Na and

  6. Triflocin, a novel inhibitor for the Na-HCO3 symport in the proximal tubule.

    PubMed Central

    Belachgar, F.; Hulin, P.; Anagnostopoulos, T.; Planelles, G.

    1994-01-01

    1. Triflocin, applied at millimolar concentration hyperpolarizes the basolateral membrane of Necturus proximal convoluted tubular cells, in vivo. 2. Barium, 2.5 x 10(-3) M, ouabain, 10(-3) M, or amiloride 10(-4) M, fail to prevent this hyperpolarization. 3. Triflocin has no effect on the intracellular chloride activity. 4. In physiological acid base conditions, Triflocin increases intracellular pH. 5. Upon an acute isohydric hypercapnia, Triflocin depolarizes the basolateral membrane potential. 6. It is concluded that, Triflocin inhibits the basolateral electrogenic Na-(HCO3)n > 1 cotransport in proximal tubules. PMID:8075865

  7. Regulation of Na-Cl absorption in rabbit proximal colon in vitro

    SciTech Connect

    Sellin, J.H.; De Siognie, R.

    1987-01-01

    Ion transport in rabbit proximal colon (PC) in vitro is dominated by a Na-Cl cotransport system stimulated by epinephrine. To further characterize the regulation of Na-Cl transport, the authors tested the effects of specific adrenergic agonists on ion fluxes under short-circuit conditions. Additionally, they tested the effects of the transport inhibitors bumetanide, furosemide, and 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS). Basal Na and Cl absorption were essentially nil. The ..cap alpha../sub 2/-agonist clonidine significantly increased net Na and Cl absorption. The ..cap alpha../sub 1/-agonist phenylephrine and the ..beta..-agonist isoproterenol did not alter ion transport. The ..cap alpha../sub 2/-blocker yohimbine (YOH) had a complex, concentration-dependent effect. Propranolol (10/sup -5/ M) and pracozin (10/sup -6/ M) did not significantly alter either basal or stimulated ion transport. Neither bumetanide (10/sup -6/ or 10/sup -4/ M) nor furosemide (10/sup -4/ M) blocked epinephrine-stimulated Na absorption. SITS (10/sup -4/ M) and removal of mucosal K did not have a significant effect on ion transport. Conclusions: 1) Na-Cl cotransport in rabbit PC is primarily under ..cap alpha../sub 2/-adrenergic control, 2) YOH at high concentrations acts as an agonist in PC, 3) ..cap alpha../sub 2/-adrenergic agonists stimulate Na-Cl absorption in both rabbit ileum and PC. In PC, however, the process is electrically quiet and therefore does not appear to be associated with electrogenic HCO/sub 3/ secretion as found in ileum, 4) the lack of effect of bumetanide, furosemide, and 0 K on Na transport suggests that a single Na-Cl (or Na-K-2Cl) carrier is not involved in Na-Cl cotransport in proximal colon.

  8. Internalization of proximal tubular type II Na-P(i) cotransporter by PTH: immunogold electron microscopy.

    PubMed

    Traebert, M; Roth, J; Biber, J; Murer, H; Kaissling, B

    2000-01-01

    Physiological/pathophysiological alterations in proximal tubular P(i) reabsorption are associated with an altered brush-border membrane (BBM) expression of type II Na-P(i) cotransporter molecules. Reduction is achieved by an internalization and lysosomal degradation and an increase in P(i) reabsorption by new synthesis and BBM insertion of type II Na-P(i) cotransporters. In the present study, we investigated by immunohistochemistry and immunogold electron microscopy the routing of internalized rat type II Na-P(i) cotransporters (NaPi-2). In kidney of rats on a chronic low-P(i) diet, NaPi-2 is mainly localized in the BBM, in cisterns of the Golgi apparatus and sparsely also in large endocytotic vacuoles and lysosomes. Fifteen minutes after the injection of the 1-34 analog of parathyroid hormone (PTH), the amount of NaPi-2 was decreased in the BBM and increased in endocytotic vesicles. NaPi-2 molecules colocalized with horseradish peroxidase injected prior to the injection of PTH. Vesicles labeled for NaPi-2 were occasionally also labeled for clathrin or the adaptor protein AP2. We conclude that NaPi-2 molecules enter the subapical compartment from where NaPi-2-containing vesicles are segregated off and directed to the lysosomes. A clathrin-mediated pathway may contribute to the PTH-induced internalization of NaPi-2. PMID:10644666

  9. Vivienda social y Falange: ideario y construcción en la década de los 40

    Microsoft Academic Search

    Jesús López Díaz

    2007-01-01

    En la España de los años 40 las diferentes familias políticas que lideraban el Régimen de Franco intentan ocupar la mayoría de los espacios políticos y sociales, en muchos casos abiertamente enfrentadas entre sí. Falange reproduce esta lucha en el campo de la arquitectura, y especialmente en el diseño de la vivienda social (con Madrid como caso paradigmático), y por

  10. Targeting of renal proximal tubule Na,K-ATPase by salt-inducible kinase.

    PubMed

    Taub, Mary; Springate, James E; Cutuli, Facundo

    2010-03-12

    The renal proximal tubule (RPT) is a central locale for Na+ reabsorption, and blood pressure regulation. Na+ reabsorption in the RPT depends upon the Na,K-ATPase, which is controlled by a complex regulatory network, including Salt-Inducible Protein Kinase (SIK). SIKs are recently discovered members of the AMP-activated Protein Kinase (AMPK) family, which regulate salt homeostasis and metabolism in a number of tissues. In the RPT, SIK interacts with the Na,K-ATPase in the basolateral membrane (BM), regulating both the activity and level of Na,K-ATPase in the BM. Thus, Na,K-ATPase activity can be rapidly adjusted in response to changes in Na+ balance. Long-term changes in Na+ intake affect the state of SIK phosphorylation, and as a consequence the phosphorylation of TORCs, Transducers of Regulated CREB (cAMP Regulatory Element Binding Protein). Once phosphorylated, TORCs enter the nucleus, and activate transcription of the ATP1B1 gene encoding for the Na,K-ATPase beta subunit. PMID:20152810

  11. Na sup + -H sup + exchanger in proximal cells isolated from rabbit kidney. I. Functional characteristics

    SciTech Connect

    Bidet, M.; Tauc, M.; Merot, J.; Vandewalle, A.; Poujeol, P. (Institut National de la Sante et de la Recherche Medicale (France))

    1987-11-01

    The purpose of this study was to investigate the characteristics of the Na{sup +}-H{sup +} exchange in isolated proximal cells from rabbit kidney cortex. The cells were prepared by mechanical dissociation and sequential passages through nylon meshes. The intracellular pH (pH{sub i}) was measured in a bicarbonate-free medium using the fluorescent dye 2,7-biscarboxyethyl-5(6)-carboxyfluorescein (BCECF). Resting pH{sub i} was 7.13 {+-} 0.04. Cells were acid loaded with nigericin in choline solution and H{sup +} efflux, induced by extracellular Na{sup +} (Na{sub e}), was calculated using a buffering power of 23.6 {+-} 0.6 mmol {center dot} l{sup {minus}1} {center dot} pH unit{sup {minus}1} estimated by NH{sub 4}Cl exposure. The intracellular H{sup +} concentration dependence did not follow simple Michaelis-Menten kinetics. Of the different cations tested on pH{sub i} recovery, such as Li{sup +}, choline{sup +}, K{sup +}, and tetramethylammonium, only Li{sup +} induced an alkalinization of acidified cells similar to that of Na{sup +}. {sup 22}Na influx measurements indicated that cellular depletion of Na{sup +} stimulated Na{sup +}-H{sup +} exchange. The results permit the conclusion that the isolation procedures did not impair the main features of the Na{sup +}-H{sup +} antiporter, at least as compared with those previously described in renal brush-border membrane vesicles or in other cellular systems. The integrity of the transporter in isolated proximal cells would permit the direct study of its hormonal and metabolic control.

  12. Regulation of renal proximal tubule Na-K-ATPase by prostaglandins

    PubMed Central

    Herman, Maryann B.; Rajkhowa, Trivikram; Cutuli, Facundo; Springate, James E.

    2010-01-01

    Prostaglandins (PGs) play a number of roles in the kidney, including regulation of salt and water reabsorption. In this report, evidence was obtained for stimulatory effects of PGs on Na-K-ATPase in primary cultures of rabbit renal proximal tubule (RPT) cells. The results of our real-time PCR studies indicate that in primary RPTs the effects of PGE2, the major renal PG, are mediated by four classes of PGE (EP) receptors. The role of these EP receptors in the regulation of Na-K-ATPase was examined at the transcriptional level. Na-K-ATPase consists of a catalytic ?-subunit encoded by the ATP1A1 gene, as well as a ?-subunit encoded by the ATP1B1 gene. Transient transfection studies conducted with pH?1-1141 Luc, a human ATP1B1 promoter/luciferase construct, indicate that both PGE1 and PGE2 are stimulatory. The evidence for the involvement of both the cAMP and Ca2+ signaling pathways includes the inhibitory effects of the myristolylated PKA inhibitor PKI, the adenylate cyclase (AC) inhibitor SQ22536, and the PKC inhibitors Gö 6976 and Ro-32-0432 on the PGE1 stimulation. Other effectors that similarly act through cAMP and PKC were also stimulatory to transcription, including norepinephrine and dopamine. In addition to its effects on transcription, a chronic incubation with PGE1 was observed to result in an increase in Na-K-ATPase mRNA levels as well as an increase in Na-K-ATPase activity. An acute stimulatory effect of PGE1 on Na-K-ATPase was observed and was associated with an increase in the level of Na-K-ATPase in the basolateral membrane. PMID:20130120

  13. Administration of adrenomedullin into subfornical organ inhibits Na(+),K(+)-ATPase activity in single proximal renal tubule of rats.

    PubMed

    Gao, Yuan; Li, Xing-Qi

    2009-02-25

    The present study was designed to investigate the effect of administration of adrenomedullin (ADM) into subfornical organ (SFO) on renal tubular Na(+),K(+)-ATPase activity in rats. Rats under anesthesia were injected with ADM 0.1 mL (20 ng/mL) via an implanted cannula into SFO (n=6). Plasma ADM and serum endogenous digitalis-like factor (EDLF) levels were assayed with radioimmunoassay, and urine samples were collected via a canoula intubated in bladder. Urinary sodium concentration was assayed with flame spectrophotometry. Single proximal renal tubule segments were obtained by hand under stereomicroscope and its Na(+),K(+)-ATPase activity was measured by liquid scintillation counting. In addition, single proximal renal tubule segments from normal rats (n=6) were incubated with serum from animals administered with ADM into SFO, and then the Na(+),K(+)-ATPase activity was determined. The results showed that both urinary volume and sodium excretion amounted to the peak value at 30 min after ADM administration, and sustained a significant high level at 60 min (P<0.01). At 30 min after ADM administration, there was a significant increase in serum EDLF and a decrease in Na(+),K(+)-ATPase activity of proximal tubule (P<0.01, respectively), but not in plasma ADM level. Na(+),K(+)-ATPase activity was decreased significantly in single proximal renal tubule segments from normal rats incubated with serum from rats administered with ADM into SFO (P<0.01). These results suggest that the diuretic and natriuretic responses following administration of ADM into SFO are associated with the inhibition of renal tubule Na(+),K(+)-ATPase activity. The inhibition of renal tubule Na(+),K(+)-ATPase activity is related to the increase in the serum level of EDLF. PMID:19224060

  14. Angiotensin II activates the ouabain-insensitive Na +ATPase from renal proximal tubules through a G-protein

    Microsoft Academic Search

    L. B. A. Rangel; C. Caruso-Neves; L. S. Lara; F. L. Brasil; A. G. Lopes

    1999-01-01

    Angiotensin II (AG II) stimulates the ouabain-insensitive, furosemide- sensitive Na+-ATPase present in the basolateral membrane of pig renal proximal tubules in a dose dependent manner. Maximum effect was obtained with 10?8 M AG II, which corresponded to an activity 134% higher than control. Half of the maximum effect was observed between 10?11 M and 10?10 M, corresponding to physiological hormone

  15. Reactive Oxygen Species Modulation of Na/K-ATPase Regulates Fibrosis and Renal Proximal Tubular Sodium Handling

    PubMed Central

    Liu, Jiang; Kennedy, David J.; Yan, Yanling; Shapiro, Joseph I.

    2012-01-01

    The Na/K-ATPase is the primary force regulating renal sodium handling and plays a key role in both ion homeostasis and blood pressure regulation. Recently, cardiotonic steroids (CTS)-mediated Na/K-ATPase signaling has been shown to regulate fibrosis, renal proximal tubule (RPT) sodium reabsorption, and experimental Dahl salt-sensitive hypertension in response to a high-salt diet. Reactive oxygen species (ROS) are an important modulator of nephron ion transport. As there is limited knowledge regarding the role of ROS-mediated fibrosis and RPT sodium reabsorption through the Na/K-ATPase, the focus of this review is to examine the possible role of ROS in the regulation of Na/K-ATPase activity, its signaling, fibrosis, and RPT sodium reabsorption. PMID:22518311

  16. Na + and K + fluxes stimulated by Na + -coupled glucose transport: Evidence for a Ba 2+ -insensitive K + efflux pathway in rabbit proximal tubules

    Microsoft Academic Search

    M. J. Avison; S. R. Gullans; T. Ogino; G. Giebisch

    1988-01-01

    Summary Addition of glucose or the nonmetabolizable analogue a-methyl-d-glucoside to rabbit proximal tubules suspended in a glucoseand alanine-free buffer caused a sustained increase in intracellular Na+ content (+43±7 nmol · (mg protein)-1) and a concomitant but larger decrease in K+ content (-72±11 nmol· (mg protein)-1). A component of the net K+ efflux was Ba2+ insensitive, and was inhibited by high

  17. Antenatal glucocorticoid treatment alters Na+ uptake in renal proximal tubule cells from adult offspring in a sex-specific manner.

    PubMed

    Su, Yixin; Bi, Jianli; Pulgar, Victor M; Figueroa, Jorge; Chappell, Mark; Rose, James C

    2015-06-01

    We have shown a sex-specific effect of fetal programming on Na(+) excretion in adult sheep. The site of this effect in the kidney is unknown. Therefore, we tested the hypothesis that renal proximal tubule cells (RPTCs) from adult male sheep exposed to betamethasone (Beta) before birth have greater Na(+) uptake than do RPTCs from vehicle-exposed male sheep and that RPTCs from female sheep similarly exposed are not influenced by antenatal Beta. In isolated RPTCs from 1- to 1.5-yr-old male and female sheep, we measured Na(+) uptake under basal conditions and after stimulation with ANG II. To gain insight into the mechanisms involved, we also measured nitric oxide (NO) levels, ANG II receptor mRNA levels, and expression of Na(+)/H(+) exchanger 3. Basal Na(+) uptake increased more in cells from Beta-exposed male sheep than in cells from vehicle-exposed male sheep (400% vs. 300%, P < 0.00001). ANG II-stimulated Na(+) uptake was also greater in cells from Beta-exposed males. Beta exposure did not increase Na(+) uptake by RPTCs from female sheep. NO production was suppressed more by ANG II in RPTCs from Beta-exposed males than in RPTCs from either vehicle-exposed male or female sheep. Our data suggest that one site of the sex-specific effect of Beta-induced fetal programming in the kidney is the RPTC and that the enhanced Na(+) uptake induced by antenatal Beta in male RPTCs may be related to the suppression of NO in these cells. PMID:25834069

  18. Voltage and cosubstrate dependence of the Na-HCO3 cotransporter kinetics in renal proximal tubule cells.

    PubMed Central

    Gross, E; Hopfer, U

    1998-01-01

    The voltage dependence of the kinetics of the sodium bicarbonate cotransporter was studied in proximal tubule cells. This electrogenic cotransporter transports one Na+, three HCO3-, and two negative charges. Cells were grown to confluence on a permeable support, mounted on a Ussing-type chamber, and permeabilized apically to small monovalent ions with amphotericin B. The steady-state, di-nitro-stilbene-di-sulfonate-sensitive current was shown to be sodium and bicarbonate dependent and therefore was taken as flux through the cotransporter. Voltage-current relations were measured as a function of Na+ and HCO3- concentrations between -160 and +160 mV under zero-trans and symmetrical conditions. The kinetics could be described by a Michaelis-Menten behavior with a Hill coefficient of 3 for HCO3- and 1 for Na+. The data were fitted to six-state ordered binding models without restrictions with respect to the rate-limiting step. All ordered models could quantitatively account for the observed current-voltage relationships and the transinhibition by high bicarbonate concentration. The models indicate that 1) the unloaded transporter carries a positive charge; 2) the binding of cytosolic bicarbonate to the transporter "senses" 12% of the electric field in the membrane, whereas its translocation across the membrane "senses" 88% of the field; 3) the binding of Na+ to the cotransporter is voltage independent. PMID:9675182

  19. Experimental study of effect of pellicle on optical proximity fingerprint for 1.35 NA immersion ArF lithography

    NASA Astrophysics Data System (ADS)

    Van Look, Lieve; Bekaert, Joost; Laenens, Bart; Vandenberghe, Geert; Richter, Jan; Bubke, Karsten; Peters, Jan Hendrik; Schreel, Koen; Dusa, Mircea

    2010-04-01

    Pellicles are mounted on the masks used in ArF lithography for IC manufacturing to ensure defect-free printing. The pellicle, a thin transparent polymer film, protects the reticle from dust. But, as the light transmittance through the pellicle has an angular dependency, the pellicle also acts as an apodization filter. In the current work, we present both experimental and simulation results at 1.35 NA immersion ArF lithography showing the influence of two types of pellicles on proximity and intra-die Critical Dimension Uniformity (CDU). To do so, we mounted and dismounted the different pellicle types on one and the same mask. The considered structures on wafer are compatible with the 32 nm logic node for poly and metal. For the standard ArF pellicle (thickness 830 nm), we experimentally observe a distinct effect of several nm's due to the pellicle presence on both the proximity and the intradie CDU. For the more advanced pellicle (thickness 280 nm) no signature of the pellicle on proximity or CDU could be found. By modeling the pellicle's optical properties as a Jones Pupil, we are able to simulate the pellicle effects with good accuracy. These results indicate that for the 32 nm node, it is recommended to take the pellicle properties into account in the OPC calculation when using a standard pellicle. In addition, simulations also indicate that a local dose correction can compensate to a large extent for the intra-die pellicle effect. When using the more advanced thin pellicle (280 nm), no such corrections are needed.

  20. Maturation of the Na+/H+ antiporter (NHE3) in the proximal tubule of the hypothyroid adrenalectomized rat

    PubMed Central

    Gupta, Neena; Dwarakanath, Vangipuram; Baum, Michel

    2014-01-01

    In previous studies examining the role of glucocorticoids and thyroid hormone on the maturation of the Na+/H+ antiporter (NHE3), we found attenuation in the maturational increase in proximal tubule apical Na+/H+ antiporter activity but no change in NHE3 mRNA abundance in either glucocorticoid-deficient or hypothyroid rats. In addition, prevention of the maturational increase in either hormone failed to totally prevent the maturational increase in Na+/H+ antiporter activity. We hypothesized that one hormone played a compensatory role when the other was deficient. The present study examined whether combined deficiency of thyroid and glucocorticoid hormones would completely prevent the maturation of the Na+/H+ antiporter. Adrenalectomy was performed in 9-day-old hypothyroid Sprague-Dawley rats, a time before the normal postnatal maturational increase in these hormones occurs. Nine- and 30-day-old adrenalectomized (ADX), hypothyroid rats had comparable NHE3 mRNA abundance, which was 5- to 10-fold less than 30-day-old ADX, hypothyroid rats that received corticosterone-thyroxine replacement and 30-day-old sham control rats (P < 0.05). Brush-border membrane NHE3 protein abundance was comparable in 9- and 30-day-old ADX, hypothyroid groups and ~20-fold lower than both the 30-day replacement and 30-day sham groups (P < 0.05). Similarly, the replacement and sham groups had higher sodium-dependent proton secretion than 9- and 30-day-old ADX, hypothyroid groups (P < 0.05). We conclude that combined deficiency of both hormones totally prevents the maturational increase in NHE3 mRNA and protein abundance and Na+/H+ antiporter activity. PMID:15113742

  1. Role of adenosine triphosphate (ATP) and NaK ATPase in the inhibition of proximal tubule transport with intracellular cystine loading.

    PubMed Central

    Coor, C; Salmon, R F; Quigley, R; Marver, D; Baum, M

    1991-01-01

    Cellular cystine loading with cystine dimethyl ester inhibits volume absorption, transepithelial potential difference, glucose transport, and bicarbonate transport in proximal convoluted tubules perfused in vitro. This study examined the roles of ATP and NaK ATPase in this in vitro model of the Fanconi syndrome of cystinosis. Intracellular ATP was measured using the luciferin-luciferase assay. Intracellular ATP was reduced by 60% in proximal convoluted tubules incubated with 0.5 mM cystine dimethyl ester for 15 min at 37 degrees C (P less than 0.001). Incubation of cystine loaded tubules with 1 mM exogenous ATP increased intracellular ATP to levels not significantly different than that of controls. On the other hand, Vmax NaK ATPase activity was unchanged even though the incubation times and the concentration of cystine dimethyl ester were doubled to 30 min and 1 mM, respectively. In proximal convoluted tubules perfused in vitro, 0.5 mM cystine dimethyl ester resulted in an 89% inhibition in volume absorption (0.81 +/- 0.14 to 0.09 +/- 0.09 nl/mm.min), while there was only a 45% inhibition in volume absorption (P less than 0.01) due to cellular cystine loading in the presence of 1 mM lumen and bath ATP (0.94 +/- 0.05 to 0.52 +/- 0.11 nl/mm.min). These data demonstrate that proximal tubule cellular cystine loading decreases cellular ATP concentration, but does not directly inhibit NaK ATPase activity. The inhibition in transport and decrease in intracellular ATP due to cellular cystine loading was ameliorated by exogenous ATP. These data are consistent with cellular ATP depletion playing a major role in the inhibition of proximal tubule transport due to intracellular cystine loading. PMID:1847941

  2. The carbohydrate moieties of the beta-subunit of Na+, K(+)-ATPase: their lateral motions and proximity to the cardiac glycoside site.

    PubMed Central

    Amler, E; Abbott, A; Malak, H; Lakowicz, J; Ball, W J

    1996-01-01

    The beta-subunit associated with the catalytic (alpha) subunit of the mammalian Na+, K(+) -ATPase is a transmembrane glycoprotein with three extracellularly located N-glycosylation sites. Although beta appears to be essential for a functional enzyme, the role of beta and its sugars remains unknown. In these studies, steady-state and dynamic fluorescence measurements of the fluorophore lucifer yellow (LY) covalently linked to the carbohydrate chains of beta have demonstrated that the bound probes are highly solvent exposed but restricted in their diffusional motions. Furthermore, the probes' environments on beta were not altered by Na+ or K+ or ouabain-induced enzyme conformational changes, but both divalent cation and oligomycin addition evoked modest changes in LY fluorescence. Frequency domain measurements reflecting the Förster fluorescence energy transfer (FET) occurring between anthroylouabain (AO) bound to the cardiac glycoside receptor site on alpha and the carbohydrate-linked LY demonstrated their close proximity (18 A). Additional FET determinations made between LY as donor and erythrosin-5-isothiocyanate, covalently bound at the enzyme's putative ATP binding site domain, indicated that a distance of about 85 A separates these two regions and that this distance is reduced upon divalent cation binding and increased upon the Na+E1-->K+E2 conformational transition. These data suggest a model for the localization of the terminal moieties of the oligosaccharides that places them, on average, about 18 A from the AO binding site and this distance or less from the extracellular membrane surface. Images FIGURE 5 PMID:8770197

  3. Proximal Nephron

    PubMed Central

    Zhuo, Jia L.; Li, Xiao C.

    2013-01-01

    The kidney plays a fundamental role in maintaining body salt and fluid balance and blood pressure homeostasis through the actions of its proximal and distal tubular segments of nephrons. However, proximal tubules are well recognized to exert a more prominent role than distal counterparts. Proximal tubules are responsible for reabsorbing approximately 65% of filtered load and most, if not all, of filtered amino acids, glucose, solutes, and low molecular weight proteins. Proximal tubules also play a key role in regulating acid-base balance by reabsorbing approximately 80% of filtered bicarbonate. The purpose of this review article is to provide a comprehensive overview of new insights and perspectives into current understanding of proximal tubules of nephrons, with an emphasis on the ultrastructure, molecular biology, cellular and integrative physiology, and the underlying signaling transduction mechanisms. The review is divided into three closely related sections. The first section focuses on the classification of nephrons and recent perspectives on the potential role of nephron numbers in human health and diseases. The second section reviews recent research on the structural and biochemical basis of proximal tubular function. The final section provides a comprehensive overview of new insights and perspectives in the physiological regulation of proximal tubular transport by vasoactive hormones. In the latter section, attention is particularly paid to new insights and perspectives learnt from recent cloning of transporters, development of transgenic animals with knockout or knockin of a particular gene of interest, and mapping of signaling pathways using microarrays and/or physiological proteomic approaches. PMID:23897681

  4. Proximal nephron.

    PubMed

    Zhuo, Jia L; Li, Xiao C

    2013-07-01

    The kidney plays a fundamental role in maintaining body salt and fluid balance and blood pressure homeostasis through the actions of its proximal and distal tubular segments of nephrons. However, proximal tubules are well recognized to exert a more prominent role than distal counterparts. Proximal tubules are responsible for reabsorbing approximately 65% of filtered load and most, if not all, of filtered amino acids, glucose, solutes, and low molecular weight proteins. Proximal tubules also play a key role in regulating acid-base balance by reabsorbing approximately 80% of filtered bicarbonate. The purpose of this review article is to provide a comprehensive overview of new insights and perspectives into current understanding of proximal tubules of nephrons, with an emphasis on the ultrastructure, molecular biology, cellular and integrative physiology, and the underlying signaling transduction mechanisms. The review is divided into three closely related sections. The first section focuses on the classification of nephrons and recent perspectives on the potential role of nephron numbers in human health and diseases. The second section reviews recent research on the structural and biochemical basis of proximal tubular function. The final section provides a comprehensive overview of new insights and perspectives in the physiological regulation of proximal tubular transport by vasoactive hormones. In the latter section, attention is particularly paid to new insights and perspectives learnt from recent cloning of transporters, development of transgenic animals with knockout or knockin of a particular gene of interest, and mapping of signaling pathways using microarrays and/or physiological proteomic approaches. PMID:23897681

  5. Functional role of glucose metabolism, osmotic stress, and sodium-glucose cotransporter isoform-mediated transport on Na+/H+ exchanger isoform 3 activity in the renal proximal tubule.

    PubMed

    Pessoa, Thaissa Dantas; Campos, Luciene Cristina Gastalho; Carraro-Lacroix, Luciene; Girardi, Adriana C C; Malnic, Gerhard

    2014-09-01

    Na(+)-glucose cotransporter 1 (SGLT1)-mediated glucose uptake leads to activation of Na(+)-H(+) exchanger 3 (NHE3) in the intestine by a process that is not dependent on glucose metabolism. This coactivation may be important for postprandial nutrient uptake. However, it remains to be determined whether SGLT-mediated glucose uptake regulates NHE3-mediated NaHCO3 reabsorption in the renal proximal tubule. Considering that this nephron segment also expresses SGLT2 and that the kidneys and intestine show significant variations in daily glucose availability, the goal of this study was to determine the effect of SGLT-mediated glucose uptake on NHE3 activity in the renal proximal tubule. Stationary in vivo microperfusion experiments showed that luminal perfusion with 5 mM glucose stimulates NHE3-mediated bicarbonate reabsorption. This stimulatory effect was mediated by glycolytic metabolism but not through ATP production. Conversely, luminal perfusion with 40 mM glucose inhibited NHE3 because of cell swelling. Notably, pharmacologic inhibition of SGLT activity by Phlorizin produced a marked inhibition of NHE3, even in the absence of glucose. Furthermore, immunofluorescence experiments showed that NHE3 colocalizes with SGLT2 but not SGLT1 in the rat renal proximal tubule. Collectively, these findings show that glucose exerts a bimodal effect on NHE3. The physiologic metabolism of glucose stimulates NHE3 transport activity, whereas, supraphysiologic glucose concentrations inhibit this exchanger. Additionally, Phlorizin-sensitive SGLT transporters and NHE3 interact functionally in the proximal tubule. PMID:24652792

  6. Proximity fuze

    DOEpatents

    Harrison, Thomas R. (Stockton, CA)

    1989-08-22

    A proximity fuze system includes an optical ranging apparatus, a detonation circuit controlled by the optical ranging apparatus, and an explosive charge detonated by the detonation cirtcuit. The optical ranging apparatus includes a pulsed laser light source for generating target ranging light pulses and optical reference light pulses. A single lens directs ranging pulses to a target and collects reflected light from the target. An optical fiber bundle is used for delaying the optical reference pulses to correspond to a predetermined distance from the target. The optical ranging apparatus includes circuitry for providing a first signal depending upon the light pulses reflected from the target, a second signal depending upon the light pulses from the optical delay fiber bundle, and an output signal when the first and second signals coincide with each other. The output signal occurs when the distance from the target is equal to the predetermined distance form the target. Additional circuitry distinguishes pulses reflected from the target from background solar radiation.

  7. Substrate specificity of the luminal Na + -dependent sulphate transport system in the proximal renal tubule as compared to the contraluminal sulphate exchange system

    Microsoft Academic Search

    C. David; K. J. Ullrich

    1992-01-01

    The efflux of [35S]sulphate from the lumen of the proximal renal tubule into tubular cells of rats was measured by the stop-flow tubular-lumen microperfusion technique. The transport parameters obtained and the apparent Ki values of competing substrates were compared with those of the contraluminal influx of [35-S]sulphate from the interstitium into tubular cells. For the luminal sulphate efflux a Km(l,

  8. Cysteine Residues and the Structure of the Rat Renal Proximal Tubular Type II Sodium Phosphate Cotransporter (Rat NaPi IIa)

    Microsoft Academic Search

    G. Lambert; I. C. Forster; J. Biber; H. Murer

    2000-01-01

    The rat renal Na\\/Pi cotransporter type IIa (rat NaPi IIa) is a 637 amino acid protein containing 12 cysteine residues. We examined the effect of different cysteine modifying methanethiosulfonate (MTS)-reagents and the disulfide bond reducing agent tris(2-carboxyethyl)phosphine (TCEP) on the transport activity of wild-type and 12 single cysteine substitution mutants of rat NaPi IIa expressed in Xenopus laevis oocytes. The

  9. Cysteine Residues and the Structure of the Rat Renal Proximal Tubular Type II Sodium Phosphate Cotransporter (Rat NaPi IIa)

    Microsoft Academic Search

    G. Lambert; I. C. Forster; J. Biber; H. Murer

    2000-01-01

    .   The rat renal Na\\/P\\u000a \\u000a i\\u000a \\u000a cotransporter type IIa (rat NaPi IIa) is a 637 amino acid protein containing 12 cysteine residues. We examined the effect of different cysteine modifying\\u000a methanethiosulfonate (MTS)-reagents and the disulfide bond reducing agent tris(2-carboxyethyl)phosphine (TCEP) on the transport\\u000a activity of wild-type and 12 single cysteine substitution mutants of rat NaPi IIa expressed in Xenopus laevis

  10. The interaction between megalin and ClC-5 is scaffolded by the Na?-H? exchanger regulatory factor 2 (NHERF2) in proximal tubule cells.

    PubMed

    Hryciw, D H; Jenkin, K A; Simcocks, A C; Grinfeld, E; McAinch, A J; Poronnik, P

    2012-05-01

    Albumin endocytosis in the proximal tubule is mediated by a number of proteins, including the scavenger receptor megalin/cubilin and the PSD-95/Dlg/ZO-1 (PDZ) scaffolds NHERF1 and NHERF2. In addition, in a number of in vitro and in vivo models, the loss of ClC-5 results in a decreased cell surface expression and whole cell level of megalin, suggesting an interaction between these two proteins in vivo. We investigated if ClC-5 and megalin interact directly, and as ClC-5 binds to NHERF2, we investigated if this PDZ scaffold was required for a megalin/ClC-5 complex. GST-pulldown and immunoprecipitation experiments using rat kidney lysate demonstrated an interaction between ClC-5 and megalin, which was mediated by their C-termini. As this interaction may be controlled by a scaffold protein, we characterised any interaction between megalin and NHERF2. Immunoprecipitation experiments indicated that megalin interacts with NHERF2 in vivo, and that this interaction was via an internal NHERF binding domain in the C-terminus of megalin and PDZ2 and the C-terminus of NHERF2. Silencing NHERF2 had no effect on megalin protein levels in the whole cell or plasma membrane. Using siRNA against NHERF2, we demonstrated that NHERF2 was required to facilitate the interaction between megalin and ClC-5. Using fusion proteins, we characterised a protein complex containing ClC-5 and megalin, which is scaffolded by NHERF2, in the absence of any other proteins. Importantly, these observations are the first to describe an interaction between megalin and ClC-5, which is scaffolded by NHERF2 in proximal tubule cells. PMID:22349218

  11. Approximate Proximity Drawings$ William Evans

    E-print Network

    Evans, Will

    Approximate Proximity Drawings$ William Evans University of British Columbia, Canada, Emden Gansner proximity drawings, called (1, 2)-proximity drawings. Intuitively, given a defi- nition of proximity and two real numbers 1 0 and 2 0, an (1, 2)-proximity drawing of a graph is a planar straight-line drawing

  12. Ontogeny of NHE8 in the rat proximal tubule.

    PubMed

    Becker, Amy M; Zhang, Jianning; Goyal, Sunita; Dwarakanath, Vangipuram; Aronson, Peter S; Moe, Orson W; Baum, Michel

    2007-07-01

    Proximal tubule bicarbonate reabsorption is primarily mediated via the Na(+)/H(+) exchanger, identified as NHE3 in adults. Previous studies have demonstrated a maturational increase in rat proximal tubule NHE3 expression, with a paucity of NHE3 expression in neonates, despite significant Na(+)-dependent proton secretion. Recently, a novel Na(+)/H(+) antiporter (NHE8) was identified and found to be expressed on the apical membrane of the proximal tubule. To determine whether NHE8 may be the antiporter responsible for proton secretion in neonates, the present study characterized the developmental expression of NHE8 in rat proximal tubules. RNA blots and real-time RT-PCR demonstrated no developmental difference in the mRNA of renal NHE8. Immunoblots, however, demonstrated peak protein abundance of NHE8 in brush border membrane vesicles of 7- and 14-day-old compared with adult rats. In contrast, the level of NHE8 expression in total cortical membrane protein was higher in adults than in neonates. Immunohistochemistry confirmed the presence of NHE8 on the apical membrane of the proximal tubules of neonatal and adult rats. These data demonstrate that NHE8 does undergo maturational changes on the apical membrane of the rat proximal tubule and may account for the Na(+)-dependent proton flux in neonatal proximal tubules. PMID:17429030

  13. Optical proximity communication

    NASA Astrophysics Data System (ADS)

    Shubin, Ivan; Cunningham, John E.; Zheng, Xuezhe; Simons, John; Feng, Dazeng; Liang, Hong; Kung, Cheng-Chih; Asghari, Mehdi; Krishnamoorthy, Ashok V.

    2009-02-01

    We review 10Gb/sec Optical Proximity Communication realized with packaged chips that carry SOI optical waveguides and reflecting mirrors micromachined in silicon. The high precision chip to chip alignment and placement was enabled by a new packaging concept based on the co-integration of pyramidal pit features defined by anisotropic silicon etch and matching high precision micro-spheres. We support this novel packaging approach with measured optical transmission data and discuss the extent of it towards other applications of Proximity Communication.

  14. Proximate Analysis of Coal

    ERIC Educational Resources Information Center

    Donahue, Craig J.; Rais, Elizabeth A.

    2009-01-01

    This lab experiment illustrates the use of thermogravimetric analysis (TGA) to perform proximate analysis on a series of coal samples of different rank. Peat and coke are also examined. A total of four exercises are described. These are dry exercises as students interpret previously recorded scans. The weight percent moisture, volatile matter,…

  15. Subacute diabetic proximal neuropathy

    NASA Technical Reports Server (NTRS)

    Pascoe, M. K.; Low, P. A.; Windebank, A. J.; Litchy, W. J.

    1997-01-01

    OBJECTIVE: To evaluate the clinical, electrophysiologic, autonomic, and neuropathologic characteristics and the natural history of subacute diabetic proximal neuropathy and its response to immunotherapy. MATERIAL AND METHODS: For the 12-year period from 1983 to 1995, we conducted a retrospective review of medical records of Mayo Clinic patients with diabetes who had subacute onset and progression of proximal weakness. The responses of treated versus untreated patients were compared statistically. RESULTS: During the designated study period, 44 patients with subacute diabetic proximal neuropathy were encountered. Most patients were middle-aged or elderly, and no sex preponderance was noted. The proximal muscle weakness often was associated with reduced or absent lower extremity reflexes. Associated weight loss was a common finding. Frequently, patients had some evidence of demyelination on nerve conduction studies, but it invariably was accompanied by concomitant axonal degeneration. The cerebrospinal fluid protein concentration was usually increased. Diffuse and substantial autonomic failure was generally present. In most cases, a sural nerve biopsy specimen suggested demyelination, although evidence of an inflammatory infiltrate was less common. Of 12 patients who received treatment (with prednisone, intravenous immune globulin, or plasma exchange), 9 had improvement of their conditions, but 17 of 29 untreated patients (59%) with follow-up also eventually had improvement, albeit at a much slower rate. Improvement was usually incomplete. CONCLUSION: We suggest that the entity of subacute diabetic proximal neuropathy is an extensive and severe variant of bilateral lumbosacral radiculoplexopathy, with some features suggestive of an immune-mediated cause. It differs from chronic inflammatory demyelinating polyradiculoneuropathy in that most cases have a more restricted distribution and seem to be monophasic and self-limiting. The efficacy of immunotherapy is unproved, but such intervention may be considered in the severe and progressive cases or ones associated with severe neuropathic pain.

  16. Proximate analysis of coal

    SciTech Connect

    Donahue, C.J.; Rais, E.A. [University of Michigan, Dearborn, MI (USA)

    2009-02-15

    This lab experiment illustrates the use of thermogravimetric analysis (TGA) to perform proximate analysis on a series of coal samples of different rank. Peat and coke are also examined. A total of four exercises are described. These are dry exercises as students interpret previously recorded scans. The weight percent moisture, volatile matter, fixed carbon, and ash content are determined for each sample and comparisons are made. Proximate analysis is performed on a coal sample from a local electric utility. From the weight percent sulfur found in the coal (determined by a separate procedure the Eschka method) and the ash content, students calculate the quantity of sulfur dioxide emissions and ash produced annually by a large coal-fired electric power plant.

  17. Isosmotic volume reabsorption in rat proximal tubule

    PubMed Central

    1980-01-01

    A theoretical model incorporation both active and passive forces has been developed for fluid reabsorption from split oil droplets in rat intermediate and late proximal tubule. Of necessity, simplifying assumptions have been introduced; we have assumed that the epithelium can be treated as a single membrane and that the membrane "effective" HCO3 permeability is near zero. Based on this model with its underlying assumptions, the following conclusions are drawn. Regardless of the presence or absence of active NaCl transport, fluid reabsorption from the split oil droplet is isosmotic. The reabsorbate osmolarity can be affected by changes in tubular permeability parameters and applied forces but is not readily altered from an osmolarity essentially equal to that of plasma. In a split droplet, isosmotic flow need not be a special consequence of active Na transport, is not the result of a particular set of permeability properties, and is not merely a trivial consequence of a very high hydraulic conductivity; isosmotic flow can be obtained with hydraulic conductivity nearly an order of magnitude lower than that previously measured in the rat proximal convoluted tubule. Isosmotic reabsorption is, in part, the result of the interdependence of salt and water flows, their changing in parallel, and thus their ratio, the reabsorbate concentration being relatively invariant. Active NaCl transport can cause osmotic water flow by reducing the luminal fluid osmolarity. In the presence of passive forces the luminal fluid can be hypertonic to plasma, and active NaCl transport can still exert its osmotic effect on volume flow. There are two passive forces for volume flow: the Cl gradient and the difference in effective osmotic pressure; they have an approximately equivalent effect on volume flow. Experimentally, we have measured volume changes in a droplet made hyperosmotic by the addition of 50 mM NaCl; the experimental results are predicted reasonably well by our theoretical model. PMID:7441196

  18. Derivative-Free Optimization Proximal Point Methods Derivative-Free Proximal Point Conclusion Derivative-Free Optimization via Proximal

    E-print Network

    Derivative-Free Optimization Proximal Point Methods Derivative-Free Proximal Point Conclusion Derivative-Free Optimization via Proximal Point Methods Yves Lucet & Warren Hare July 24, 2013 1 / 26 #12;Derivative-Free Optimization Proximal Point Methods Derivative-Free Proximal Point Conclusion Outline 1

  19. Preserving average proximity in arrays

    Microsoft Academic Search

    Richard A. DeMillo; Stanley C. Eisenstat; Richard J. Lipton

    1978-01-01

    Programmers and data structure designers are often forced to choose between alternative structures. In storing these structures, preserving logical adjacencies or “proximity” is usually an important consideration. The combinatorial problem of storing arrays as various kinds of list structures is examined. Embeddings of graphs are used to model the loss of proximity involved in such storage schemes, and an elementary

  20. Chloride reabsorption by renal proximal tubules of necturus

    Microsoft Academic Search

    Kenneth R. Spring; Genjiro Kimura

    1978-01-01

    Summary Movement of Cl from the lumen ofNecturus proximal tubule into the cells is mediated and dependent on the presence of luminal Na. Intracellular Cl activity was monitored with ion selective microelectrodes. In Cl Ringer's perfused kidneys, cell Cl activity was 24.5±1.1mm, 2 to 3 times higher than that predicted for passive distribution. When luminal NaCl was partially replaced by

  1. Tools for proximal soil sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proximal soil sensing (i.e. near-surface geophysical methods) are used to study soil phenomena across spatial scales. Geophysical methods exploit contrasts in physical properties (dielectric permittivity, apparent electrical conductivity or resistivity, magnetic susceptibility) to indirectly measur...

  2. Proximal Gastrectomy for Gastric Cancer

    PubMed Central

    Jung, Do Hyun; Ahn, Sang-Hoon; Kim, Hyung-Ho

    2015-01-01

    Laparoscopic proximal gastrectomy (LPG) is theoretically a superior choice of minimally-invasive surgery and function-preserving surgery for the treatment of proximal early gastric cancer (EGC) over procedures such as laparoscopic total gastrectomy (LTG), open total gastrectomy (OTG) and open proximal gastrectomy (OPG). However, LPG and OPG are not popular surgical options due to three main concerns: the first, oncological safety; the second, functional benefits; and the third, anastomosis-related late complications (reflux symptoms and anastomotic stricture). Numerous recent studies have concluded that OPG and LPG present similar oncological safety profiles and improved functional benefits when compared with OTG and LTG. While OPG with modified esophagogastrostomy does not provide satisfactory results, OPG with modified esophagojejunostomy showed similar rates of anastomosis-related late complications when compared to OTG. At this stage, no standard reconstruction method post-LPG exists in the clinical setting. We recently showed that LPG with double tract reconstruction (DTR) is a superior choice over LTG for proximal EGC in terms of maintaining body weight and preventing anemia. However, as there is no definitive evidence in favor of LPG with DTR, a randomized clinical trial comparing LPG with DTR to LTG was recommended. This trial, the Korean Laparoscopic Gastrointestinal Surgery Study-05 (NCT01433861), is expected to assist surgeons in choice of surgical approach and strategy for patients with proximal EGC.

  3. Transcellular Chloride Pathways in Ambystoma Proximal Tubule

    Microsoft Academic Search

    S. Abdulnour-Nakhoul; E. L. Boulpaep

    1998-01-01

    .   The transport mechanisms of Ambystoma proximal tubule that mediate transcellular Cl? absorption linked to Na+ were investigated in isolated perfused tubules using Cl?-selective and voltage-recording microelectrodes. In control solutions intracellular activity of Cl? (a\\u000a \\u000a \\u000a \\u000a i\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a Cl\\u000a \\u000a ) is 11.3 ? 0.5 mm, the basolateral (V\\u000a \\u000a \\u000a \\u000a 1\\u000a \\u000a ), apical (V\\u000a \\u000a \\u000a \\u000a 2\\u000a \\u000a ), and transepithelial (V\\u000a \\u000a \\u000a \\u000a 3\\u000a \\u000a ) potential differences are

  4. Nonequilibrium thermodynamic model of the rat proximal tubule epithelium.

    PubMed Central

    Weinstein, A M

    1983-01-01

    The rat proximal tubule epithelium is represented as well-stirred, compliant cellular and paracellular compartments bounded by mucosal and serosal bathing solutions. With a uniform pCO2 throughout the epithelium, the model variables include the concentrations of Na, K, Cl, HCO3, H2PO4, HPO4, and H, as well as hydrostatic pressure and electrical potential. Except for a metabolically driven Na-K exchanger at the basolateral cell membrane, all membrane transport within the epithelium is passive and is represented by the linear equations of nonequilibrium thermodynamics. In particular, this includes the cotransport of Na-Cl and Na-H2PO4 and countertransport of Na-H at the apical cell membrane. Experimental constraints on the choice of ionic conductivities are satisfied by allowing K-Cl cotransport at the basolateral membrane. The model equations include those for mass balance of the nonreacting species, as well as chemical equilibrium for the acidification reactions. Time-dependent terms are retained to permit the study of transient phenomena. In the steady state the energy dissipation is computed and verified equal to the sum of input from the Na-K exchanger plus the Gibbs free energy of mass addition to the system. The parameter dependence of coupled water transport is studied and shown to be consistent with the predictions of previous analytical models of the lateral intercellular space. Water transport in the presence of an end-proximal (HCO3-depleted) luminal solution is investigated. Here the lower permeability and higher reflection coefficient of HCO3 enhance net sodium and water transport. Due to enhanced flux across the tight junction, this process may permit proximal tubule Na transport to proceed with diminished energy dissipation. PMID:6652211

  5. Shuttle rendezvous and proximity operations

    NASA Technical Reports Server (NTRS)

    Pearson, Don J.

    1990-01-01

    Shuttle rendezvous and proximity operations trajectory control techniques are reviewed and it is noted that they have been affected by many factors including Shuttle system design constraints such as limited forward RCS and single point radar failures. Crew training requirements and mission operations constraints such as large launch windows, flexibility, and contingency profile interrupts are also integral factors. The resulting trajectory control design primarily uses ground support for the launch and orbit adjust phases, standardized crew techniques utilizing onboard software for the relative navigation flight phase, and mission unique manual control for a flexible proximity operations phase.

  6. Laterally proximized aluminum tunnel junctions

    NASA Astrophysics Data System (ADS)

    Koski, J. V.; Peltonen, J. T.; Meschke, M.; Pekola, J. P.

    2011-05-01

    This letter presents experiments on junctions fabricated by a technique that enables the use of high-quality aluminum oxide tunnel barriers with normal metal electrodes at low temperatures. Inverse proximity effect is applied to diminish the superconductivity of an aluminum dot through a clean lateral connection to a normal metal electrode. To demonstrate the effectiveness of this method, fully normal-state single electron transistors (SETs) and normal metal-insulator-superconductor (NIS) junctions applying proximized Al junctions were fabricated. The transport characteristics of the junctions were similar to those obtained from standard theoretical models of regular SETs and NIS junctions.

  7. Driven shielding capacitive proximity sensor

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor); McConnell, Robert L. (Inventor)

    2000-01-01

    A capacitive proximity sensing element, backed by a reflector driven at the same voltage as and in phase with the sensor, is used to reflect the field lines away from a grounded robot arm towards an intruding object, thus dramatically increasing the sensor's range and sensitivity.

  8. Proximity problems on moving points

    Microsoft Academic Search

    Julien Basch; Leonidas J. Guibas; Li Zhang

    1997-01-01

    A kinetic data structure for the maintenance of a multidimensional range search tree is introduced. This structure is used as a building block to obtain kinetic data structures for two classical geometric proximity problems in arbitrary dimensions: the first structure maintains the closest pair of a set of continuously moving points, and is provably efficient. The second structure maintains a

  9. Range-Aggregate Proximity Queries

    Microsoft Academic Search

    R. Sharathkumar; Prosenjit Gupta

    In a range-aggegate query problem we wish to preprocess a set S of geometric objects such that given a query orthogonal range q, a certain intersection or proximity query on the objects of S intersected by q can be answered efficiently. Although range-aggregate queries have been widely investigated in the past for aggregation functions like average, count, min, max, sum

  10. Radio Proximity-Fuze Development

    Microsoft Academic Search

    C. Brunetti

    1946-01-01

    The general principles governing the design of radio proximity fuzes are presented. The paper deals primarily with fuzes for smooth-bore projectiles, such as bombs, rockets, and mortars. Illustrations and descriptions of the various fuzes in this category which were developed during World War II are given. Within security regulations, there is a reasonably detailed discussion of the performance and constraction

  11. Reabsorption of sodium in the proximal renal tubule in cirrhosis of the liver.

    PubMed Central

    Chiandussi, L; Bartoli, E; Arras, S

    1978-01-01

    Proximal tubular reabsorption was examined in patients with liver cirrhosis and ascites by a variety of indirect methods. Maximal diluting ability, urine flow rate, and free water clearance were reduced. During frusemide administration V/GFR was lower than in normal control subjects, indicating that proximal fractional reabsorption is enhanced in liver cirrhosis. This, by reducing Na delivery to the loop of Henle, impairs maximal urine osmolality. Mannitol, by reducing proximal reabsorption, restores availability of Na to the loop and urine concentrating ability during osmotic diuresis, whereas volume expansion with dextran was ineffective. This could be due to a persistent increase in renal vascular resistance preventing the rise in interstitial pressure responsible for driving fluid back into the proximal tubular lumen. PMID:680584

  12. Proximity Graphs on Line Segments

    Microsoft Academic Search

    Prosenjit Bose; Godfried Toussaint

    presents a barrier. Therefore, in this case, it may be better toomit the closest pair.ab cdefFigure 1: Closest pairs may not be part of the proximity graph.Lee [Lee78] first addressed these problems in the context of Delaunay triangulations. His goalwas the following: Given a set of n vertices in the plane together with a set of non-crossing edges,1find a triangulation

  13. Modeling oxygen consumption in the proximal tubule: effects of NHE and SGLT2 inhibition.

    PubMed

    Layton, Anita T; Vallon, Volker; Edwards, Aurélie

    2015-06-15

    The objective of this study was to investigate how physiological, pharmacological, and pathological conditions that alter sodium reabsorption (TNa) in the proximal tubule affect oxygen consumption (QO2 ) and Na(+) transport efficiency (TNa/QO2 ). To do so, we expanded a mathematical model of solute transport in the proximal tubule of the rat kidney. The model represents compliant S1, S2, and S3 segments and accounts for their specific apical and basolateral transporters. Sodium is reabsorbed transcellularly, via apical Na(+)/H(+) exchangers (NHE) and Na(+)-glucose (SGLT) cotransporters, and paracellularly. Our results suggest that TNa/QO2 is 80% higher in S3 than in S1-S2 segments, due to the greater contribution of the passive paracellular pathway to TNa in the former segment. Inhibition of NHE or Na-K-ATPase reduced TNa and QO2 , as well as Na(+) transport efficiency. SGLT2 inhibition also reduced proximal tubular TNa but increased QO2 ; these effects were relatively more pronounced in the S3 vs. the S1-S2 segments. Diabetes increased TNa and QO2 and reduced TNa/QO2 , owing mostly to hyperfiltration. Since SGLT2 inhibition lowers diabetic hyperfiltration, the net effect on TNa, QO2 , and Na(+) transport efficiency in the proximal tubule will largely depend on the individual extent to which glomerular filtration rate is lowered. PMID:25855513

  14. Tumor-promoting phorbol esters effect alkalinization of canine renal proximal tubular cells

    SciTech Connect

    Mellas, J.; Hammerman, M.R.

    1986-03-01

    We have demonstrated the presence of specific receptors for tumor-promoting phorbol esters in the plasma membrane of the canine renal proximal tubular cell. These compounds affect proximal tubular metabolism in vitro. For example, we have shown that they inhibit gluconeogenesis in canine renal proximal tubular segments. Tumor-promoting phorbol esters have been shown to effect alkalinization of non-renal cells, by enhancing Na/sup +/-H/sup +/ exchange across the plasma membrane. To determine whether the actions of tumor-promoting phorbol esters in proximal tubular segments might be mediated by a similar process, we incubated suspensions of segments from dog kidney with these compounds and measured changes in intracellular pH using (/sup 14/C)-5,5-dimethoxazoladine-2-4-dione (DMO) and flow dialysis. Incubation of segments with phorbol 12,13 dibutyrate, but not inactive phorbol ester, 4 ..gamma.. phorbol, effected alkalinization of cells within the segments in a concentration-dependent manner. Alkalinization was dependent upon the presence of extracellular (Na/sup +/) > intracellular (Na/sup +/), was prevented by amiloride and was demonstrable in the presence of SITS. Our findings suggest that tumor-promoting esters stimulate the Na/sup +/-H/sup +/ exchanger known to be present in the brush border membrane of the renal proximal tubular cell. It is possible that the stimulation reflects a mechanism by which phorbol esters affect metabolic processes in these cells.

  15. The HTV Proximity Communication System

    NASA Astrophysics Data System (ADS)

    Harada, Motoyuki; Takahashi, Tetsuo; Tanaka, Tetsuo

    2002-01-01

    National Space Development Agency of Japan (NASDA) is developing the H-II Transfer Vehicle (HTV) as an unmanned logistic support vehicle for the International Space Station (ISS). The HTV, which is launched by the H-IIA rocket, transports both pressurized and un-pressurized cargoes to the ISS, reloads disposal items from the ISS and performs destructive reentry over ocean area. NASDA plans the first flight of HTV in 2005 for demonstration. The HTV will contribute the ISS assembly and logistic re-supply operations with international commonality. For unmanned vehicle operation, communication link is critical with commanding and control, especially in proximity region to the ISS. As for the HTV operation, NASDA is developing dedicated communication system installed on the Japanese Experiment Module (JEM) of the ISS, which is called the Proximity Communication System (PROX). The HTV receives commands and transmits telemetry data through the PROX in its proximity operation to the ISS. To achieve this, the PROX can communicate with the HTV on its nominal trajectory within 23km of the ISS. Especially within 3km of the ISS, the PROX has capability to perform omni-directional communication to the HTV. The PROX also has GPS receiver and send GPS data to the HTV to support the HTV navigation for relative GPS navigation used in "far" range (500m away from the ISS). In addition to the above fundamental functions, the PROX has a capability of range and range-rate measurement between the ISS and the HTV by the pseudo noise (PN) code epoch and the Doppler shift frequency. This provides a reference data independent of "main" navigation methods (rendezvous sensor navigation or GPS navigation) of the HTV. The PROX also assists the ISS crew with its commanding device, called the Hardware Command Panel (HCP), to issue time-dependent safety-related critical commands for HTV berthing/un-berthing operation. When a failure occurs somewhere on "communication path" from the PROX Base Band Processor (BBP) to the HTV Guidance and Control Computer (GCC) including data handling and communication equipments, the PROX detects it by monitoring interruption of the "heartbeat" signal and conducts automatic redundancy switching of all the equipments on that "communication path" including those of the HTV. This paper describes the PROX functions such as communication, data handling and GPS navigation and some unique functions for the HTV proximity operation to the ISS.

  16. Proximity bias swing: origin and characterization

    NASA Astrophysics Data System (ADS)

    Zandbergen, Peter; Gehoel-van Ansem, Wendy F.; de Klerk, Jos; Vandenberghe, Geert; Linskens, Frank T.

    1998-06-01

    Isolated to dense linewidth offsets, also known as proximity bias, can consume a significant portion of the CD budget. As a result, it has received great attention over the recent years. It is demonstrated that proximity bias shows a cyclic swing behavior on reflective substrates with respect to resist thickness variations. The amplitude of proximity bias swing was found to be influenced by coherence, substrate reflectivity, feature dimension and pitch. Proximity bias swing is caused by differences in optical path lengths of light passing through the resist film. Due to different diffraction angles for different pitches, the incoupling positions for different pitches vary. The offset in CD swing incoupling positions for different pitches results in proximity bias swing. At low coherence however, an averaging effect on diffraction angles from different pitches takes place due to the wide range of angles of light passing through the mask. In addition, the impact of exposure margin variations on resolution and proximity bias was demonstrated. Low exposure margins offer high resolution. As a consequence, high proximity bias is observed. Furthermore, different line to space ratios were studied to identify the transition point between dense and isolated features with respect to proximity bias swing. At high coherence ((sigma) equals 0.35) it was observed that for 0.25 micrometers features with pitches smaller than 0.65 micrometers , proximity bias swing is larger than the +/- 0.5% CD budget, which makes it impossible to do effective application of proximity bias correction schemes. At low coherence, only limited proximity bias swing was found. Through variation of bake conditions it was demonstrated that these process variations had no measurable effect on proximity bias swing. Optical settings, in combination with substrate reflectivity, are the main contributors to (eliminate) proximity bias swing.

  17. Proximal bodies in hypersonic flow

    SciTech Connect

    Deiterding, Ralf [ORNL; Laurence, Stuart J [California Institute of Technology, Pasadena; Hornung, Hans G [California Institute of Technology, Pasadena

    2007-01-01

    Hypersonic flows involving two or more bodies travelling in close proximity to one another are encountered in several important situations, both natural and man-made. The present work seeks to investigate one aspect of the resulting flow problem by exploring the forces experienced by a secondary body when it is within the domain of influence of a primary body travelling at hypersonic speeds. An analytical methodology based on the blast wave analogy is developed and used to predict the secondary force coefficients for simple geometries in both two and three dimensions. When the secondary body is entirely inside the primary shocked region, the nature of the lateral force coefficient is found to depend strongly on the relative size of the two bodies. For two spheres, the methodology predicts that the secondary body will experience an exclusively attractive lateral force if the secondary diameter is larger than one-sixth the primary diameter. The analytical results are compared with those from numerical simulations and reasonable agreement is observed if an appropriate normalization for the lateral displacement is used. Results from a series of experiments in the T5 hypervelocity shock tunnel are also presented and compared with perfect-gas numerical simulations, with good agreement. A new force-measurement technique for short-duration hypersonic facilities, enabling the experimental simulation of the proximal bodies problem, is described. This technique provides two independent means of measurement, and the agreement observed between the two gives a further degree of confidence in the results obtained.

  18. Fast proximity correction with zone sampling

    NASA Astrophysics Data System (ADS)

    Stirniman, John P.; Rieger, Michael L.

    1994-05-01

    Proximity effects cause integrated circuit features to be distorted when compared to the original mask pattern. These effects are becoming widely recognized as serious barriers to achieving effective half-micrometer and smaller wafer lithography processes. A promising remedy for proximity effects is to adjust mask feature shapes to compensate for predictable distortions in the wafer lithography process. We present a general method for computing proximity-corrected shapes. A technique we call `zone sampling' provides accurate models of proximity behaviors with optimum computational efficiency. Proximity behavior for arbitrary layout configurations is derived from 2-D density measurements (zone samples) computed from IC layout pattern data. Zone sampling provides a complete `behavior model' of combined, non-linear proximity effects, including optical, process, and underlying substrate mechanisms.

  19. Hyaluronan and proximal tubular cell migration

    Microsoft Academic Search

    TAKAFUMI ITO; JOHN D WILLIAMS; SAPHWAN AL-ASSAF; Glyn O. Phillips; Aled O. Phillips

    2004-01-01

    Hyaluronan and proximal tubular cell migration.BackgroundThe ubiquitous polysaccharide hyaluronan has been associated with both acute renal injury and progressive renal disease. The aim of this study was to examine the effect of hyaluronan on proximal tubular cell migration.MethodsThe proximal tubular cell line, HK-2 cells, were grown in monolayer culture, and cell migration following addition of hyaluronan characterized in an in

  20. Proximal humeral fractures: pin, plate, or replace.

    PubMed

    Neviaser, Robert J; Resch, Herbert; Neviaser, Andrew S; Crosby, Lynn A

    2015-01-01

    Proximal humeral fractures are becoming increasingly common in individuals older than 60 years, with only fractures of the hip and distal radius occurring with a higher frequency. Most proximal humeral fractures can be managed without surgery; however, if a fracture is displaced or angulated, surgical treatment may be required. There are four main options for the surgical management of proximal humeral fractures: minimally invasive percutaneous reduction and fixation, open reduction and periarticular plating, hemiarthroplasty, and reverse total shoulder arthroplasty. PMID:25745906

  1. Regulation of renal proximal tubule basolateral potassium channels.

    PubMed

    Sackin, H

    1990-01-01

    In summary, these studies report a voltage-gated, stretch-activated K channel at the basolateral membrane of amphibian proximal tubule. In the normal range of potential, any reduction in metabolic activity leading to membrane depolarization would reduce the open-probability of the basolateral K channel, thereby preventing excessive loss of K out of the cell. This type of voltage gating is consistent with the decrease in macroscopic K conductance observed in perfused frog tubules after cell depolarization (Messner et al., 1985). However, it does not account for the delayed increase in basolateral K conductance that accompanies Na-substrate cotransport across the apical membrane. The stretch-activation property of basolateral K channels may explain both electrolyte and volume homeostasis in the amphibian proximal tubule. Na-substrate cotransport produces a gradual increase in cell volume in several preparations (Hempling and Hare 1961; Hacking and Eddy 1981; Hudson and Schultz 1988;). Hence, the observed increase in K conductance during luminal addition of Na-cotransported substrates may be mediated by small changes in cell volume. For example, a stretch-activated K channel, stimulated by a 1% increase in cell volume, would allow K to exit the cell down its electrochemical gradient, thereby balancing the increased K uptake associated with greater Na pump activity. A number of studies have provided evidence that cell swelling increases macroscopic K conductance (Davis and Finn 1982; Germann et al. 1986; Grinstein et al. 1982; Grinstein et al. 1984; Hamill 1983; Hoffmann 1985; Lau et al. 1984; Lopes and Guggino 1987; Richards and Dawson 1986) as well as chloride channel activity (Hudson and Schultz 1988). However, the present study is the first to suggest that the swelling-induced increase in basolateral K conductance results from stretch-activated K channels. This same stretch-activation property may also be involved in the VRD that occurs during exposure of proximal tubule cells to hypotonic media (Dellesaga and Grantham 1973; Welling et al. 1985; Lopes and Guggino 1987; Kirk et al 1987). Since cell swelling undoubtably increases membrane tension (Kelly and Macklem 1988), swollen amphibian proximal tubule cells would lose K because of an increase in the open probability of stretch-activated K channels. The additional exit of bicarbonate and water would restore the cells to their original volume. PMID:2408069

  2. Ensemble: cooperative proximity-based authentication

    Microsoft Academic Search

    Andre Kalamandeen; Adin Scannell; Eyal de Lara; Anmol Sheth; Anthony LaMarca

    2010-01-01

    Ensemble is a system that uses a collection of trusted personal devices to provide proximity-based authentication in pervasive environments. Users are able to securely pair their personal devices with previously unknown devices by simply placing them close to each other (e.g., users can pair their phones by just bringing them into proximity). Ensemble leverages a user's growing collection of trusted

  3. Disorders of the Renal Proximal Tubule

    Microsoft Academic Search

    Arend Bökenkamp; Michael Ludwig

    2011-01-01

    Following glomerular filtration, the bulk of solutes are reabsorbed in the proximal tubule to prevent excessive losses of vital metabolites. In this nephron segment, reabsorption is largely active via dedicated transporters. Hereditary defects in proximal tubular function are characterized by malabsorption affecting amino acids, glucose, potassium, phosphate, bicarbonate, low-molecular-weight proteins and other solutes handled by this nephron segment. Dysfunction may

  4. Rheogenic sodium-bicarbonate cotransport in the peritubular cell membrane of rat renal proximal tubule

    Microsoft Academic Search

    K. Yoshitomi; B.-Ch. Burckhardt; E. Frömter

    1985-01-01

    The mechanism of bicarbonate transport across the peritubular cell membrane was investigated in rat kidney proximal tubules in situ by measuring cell pH and cell Na+ activity in response to sudden reduction of peritubular Na+ and\\/or HCO3-. The following observations were made: 1. sudden peritubular reduction of either ion concentration produced the same transient depolarizing potential response; 2. bicarbonate efflux

  5. Partial recovery of in vivo function by improved incubation conditions of isolated renal proximal tubule

    Microsoft Academic Search

    S. Müller-Berger; S. Coppola; I. Samaržija; G. Seki; E. Frömter

    1997-01-01

    Isolated microperfused rabbit renal proximal tubule S2 segments, if incubated in conventional substrate containing HCO3\\u000a –Ringer solution, exhibit lower cell membrane potentials (V\\u000a b) and elevated intracellular Na+ concentrations ([Na]i) compared to rat tubules in vivo. Assuming that these and other differences reflect insufficient metabolic and\\/or hormonal\\u000a stimulation of the cells, we have used microelectrode techniques to test whether improving

  6. Optical proximity sensors for manipulators

    NASA Technical Reports Server (NTRS)

    Johnson, A. R.

    1973-01-01

    A breadboard optical proximity sensor intended for application to remotely operated manipulators has been constructed and evaluated in the laboratory. The sensing head was 20 mm x 15 mm x 10 mm in size, and could be made considerably smaller. Several such devices could be conveniently mounted on a manipulator hand, for example, to align the hand with an object. Type 1 and Type 2 optical configurations are discussed, Type 1 having a sharply defined sensitive volume, Type 2 an extended one. The sensitive volume can be placed at any distance between 1 cm and approximately 1 m by choice of a replaceable prism. The Type 1 lateral resolution was 0.5 mm on one axis and 5 mm perpendicular to it for a unit focused at 7.5 cm. The corresponding resolution in the axial direction was 2.4 cm, but improvement to 0.5 cm is possible. The effect of surface reflectivity is discussed and possible modes of application are suggested.

  7. Range gated strip proximity sensor

    DOEpatents

    McEwan, Thomas E. (Livermore, CA)

    1996-01-01

    A range gated strip proximity sensor uses one set of sensor electronics and a distributed antenna or strip which extends along the perimeter to be sensed. A micro-power RF transmitter is coupled to the first end of the strip and transmits a sequence of RF pulses on the strip to produce a sensor field along the strip. A receiver is coupled to the second end of the strip, and generates a field reference signal in response to the sequence of pulse on the line combined with received electromagnetic energy from reflections in the field. The sensor signals comprise pulses of radio frequency signals having a duration of less than 10 nanoseconds, and a pulse repetition rate on the order of 1 to 10 MegaHertz or less. The duration of the radio frequency pulses is adjusted to control the range of the sensor. An RF detector feeds a filter capacitor in response to received pulses on the strip line to produce a field reference signal representing the average amplitude of the received pulses. When a received pulse is mixed with a received echo, the mixing causes a fluctuation in the amplitude of the field reference signal, providing a range-limited Doppler type signature of a field disturbance.

  8. Range gated strip proximity sensor

    DOEpatents

    McEwan, T.E.

    1996-12-03

    A range gated strip proximity sensor uses one set of sensor electronics and a distributed antenna or strip which extends along the perimeter to be sensed. A micro-power RF transmitter is coupled to the first end of the strip and transmits a sequence of RF pulses on the strip to produce a sensor field along the strip. A receiver is coupled to the second end of the strip, and generates a field reference signal in response to the sequence of pulse on the line combined with received electromagnetic energy from reflections in the field. The sensor signals comprise pulses of radio frequency signals having a duration of less than 10 nanoseconds, and a pulse repetition rate on the order of 1 to 10 MegaHertz or less. The duration of the radio frequency pulses is adjusted to control the range of the sensor. An RF detector feeds a filter capacitor in response to received pulses on the strip line to produce a field reference signal representing the average amplitude of the received pulses. When a received pulse is mixed with a received echo, the mixing causes a fluctuation in the amplitude of the field reference signal, providing a range-limited Doppler type signature of a field disturbance. 6 figs.

  9. Promoting proximal formative assessment with relational discourse

    NASA Astrophysics Data System (ADS)

    Scherr, Rachel E.; Close, Hunter G.; McKagan, Sarah B.

    2012-02-01

    The practice of proximal formative assessment - the continual, responsive attention to students' developing understanding as it is expressed in real time - depends on students' sharing their ideas with instructors and on teachers' attending to them. Rogerian psychology presents an account of the conditions under which proximal formative assessment may be promoted or inhibited: (1) Normal classroom conditions, characterized by evaluation and attention to learning targets, may present threats to students' sense of their own competence and value, causing them to conceal their ideas and reducing the potential for proximal formative assessment. (2) In contrast, discourse patterns characterized by positive anticipation and attention to learner ideas increase the potential for proximal formative assessment and promote self-directed learning. We present an analysis methodology based on these principles and demonstrate its utility for understanding episodes of university physics instruction.

  10. Proof of Proximity of Knowledge Serge Vaudenay

    E-print Network

    applications such as NFC-based payment: for small payments, there is typically no action required,24,25]. Actually, some commercial NFC cards by NXP1 are already supposed to implement "proximity checks against

  11. A fast distributed proximal-gradient method

    E-print Network

    Chen, Annie I.

    We present a distributed proximal-gradient method for optimizing the average of convex functions, each of which is the private local objective of an agent in a network with time-varying topology. The local objectives have ...

  12. Customized proximal point algorithms for linearly constrained ...

    E-print Network

    2011-10-30

    Oct 30, 2011 ... and it has been well studied in various fields such as the partial ..... theoretical restrictions or numerical choices on the metric proximal parameter. ... of their MVI reformulations are potential to decompose the generic PPA task ...

  13. Control of spacecraft in proximity orbits

    E-print Network

    Breger, Louis Scott, 1979-

    2007-01-01

    Formation flying of spacecraft and autonomous rendezvous and docking of spacecraft are two missions in which satellites operate in close proximity and their relative trajectories are critically important. Both classes of ...

  14. Implementing Probabilistically Checkable Proofs of Proximity

    E-print Network

    Bhattacharyya, Arnab

    2005-08-08

    Abstract: In this paper, we describe a proof-of-concept implementation of the probabilistically checkable proof of proximity (PCPP) system described by Ben-Sasson and Sudan in \\\\cite{bs05}. In particular, we implement a ...

  15. Opportunistic, collaborative and synchronized, proximal device ecology

    E-print Network

    Toledano, Eyal

    2013-01-01

    CoSync is an on-device software framework for coordinating proximal consumer electronic devices in order to create a synchronized, opportunistic and collaborative device ecology. The CoSync device ecology combines multiple ...

  16. Sodium Flux in Necturus Proximal Tubule under Voltage Clamp

    PubMed Central

    Spring, Kenneth R.; Paganelli, Charles V.

    1972-01-01

    Na transport and electrical properties of Necturus renal proximal tubules were analyzed, in vivo, by a voltage clamp method which utilizes an axial electrode in the tubule lumen for passage of current and simultaneous determination of net fluid (or Na) flux by the split droplet method. When the average spontaneous transepithelial potential difference of –8 mv (lumen negative) was reduced to zero by current passage, net Na flux doubled from a mean of 107 to 227 pmoles/cm2 per sec. The relationship between flux and potential over the range –25 to +10 mv was nonlinear, with flux equilibrium at –15 mv and droplet expansion at more negative values. Calculated Na permeability at flux equilibrium was 7.0 x 10–6 cm/sec. Voltage transients, similar to those caused by intraepithelial unstirred layers, were observed at the end of clamping periods. Tubular electrical resistance measured by brief square or triangle wave pulses (<100 msec) averaged 43 ohm cm2. The epithelial current-voltage relationship was linear over the range –100 to +100 mv, but displayed marked hysteresis during low frequency (<0.04 Hz) triangle wave clamps. The low transepithelial resistance and large opposing unidirectional ion fluxes suggest that passive ionic movements occur across extracellular shunt pathways, while the voltage transients and current-voltage hysteresis are consistent with the development of a local osmotic gradient within epithelium. PMID:5049078

  17. A proximate perspective on reciprocal altruism

    Microsoft Academic Search

    Sarah F. Brosnan; Frans B. M. de Waal

    2002-01-01

    The study of reciprocal altruism, or the exchange of goods and services between individuals, requires attention to both evolutionary\\u000a explanations and proximate mechanisms. Evolutionary explanations have been debated at length, but far less is known about\\u000a the proximate mechanisms of reciprocity. Our own research has focused on the immediate causes and contingencies underlying\\u000a services such as food sharing, grooming, and

  18. Proximity sensor system development. CRADA final report

    SciTech Connect

    Haley, D.C. [Oak Ridge National Lab., TN (United States); Pigoski, T.M. [Merrit Systems, Inc. (United States)

    1998-01-01

    Lockheed Martin Energy Research Corporation (LMERC) and Merritt Systems, Inc. (MSI) entered into a Cooperative Research and Development Agreement (CRADA) for the development and demonstration of a compact, modular proximity sensing system suitable for application to a wide class of manipulator systems operated in support of environmental restoration and waste management activities. In teleoperated modes, proximity sensing provides the manipulator operator continuous information regarding the proximity of the manipulator to objects in the workspace. In teleoperated and robotic modes, proximity sensing provides added safety through the implementation of active whole arm collision avoidance capabilities. Oak Ridge National Laboratory (ORNL), managed by LMERC for the United States Department of Energy (DOE), has developed an application specific integrated circuit (ASIC) design for the electronics required to support a modular whole arm proximity sensing system based on the use of capacitive sensors developed at Sandia National Laboratories. The use of ASIC technology greatly reduces the size of the electronics required to support the selected sensor types allowing deployment of many small sensor nodes over a large area of the manipulator surface to provide maximum sensor coverage. The ASIC design also provides a communication interface to support sensor commands from and sensor data transmission to a distributed processing system which allows modular implementation and operation of the sensor system. MSI is a commercial small business specializing in proximity sensing systems based upon infrared and acoustic sensors.

  19. Proximal tubular cell sodium concentration in early diabetic nephropathy assessed by electron microprobe analysis.

    PubMed

    Pollock, C A; Field, M J; Bostrom, T E; Dyne, M; Gyory, A Z; Cockayne, D J

    1991-03-01

    Electron microprobe X-ray analysis techniques were employed in order to assess the changes that occur in proximal tubular cell sodium concentration during the hyperfiltration phase of early diabetes mellitus induced by streptozotocin in Sprague Dawley rats. Intracellular rubidium accumulation following intravenous infusion of rubidium chloride was used as a marker of basolateral Na/K-ATPase activity. The diabetic animals studied had a significantly higher glomerular filtration rate compared with controls [1.44 +/- 0.07 vs. 1.00 +/- 0.07 ml min-1 (100 g body weight)-1; mean +/- SEM, P less than 0.001]. Intracellular Na concentration was significantly higher in diabetic animals (19.5 +/- 0.6 vs. 17.8 +/- 0.4 mmol/kg wet weight; P less than 0.01). Concurrent measurement of Rb demonstrated significantly higher intracellular accumulation in the proximal tubules of diabetic animals compared with control (7.9 +/- 0.5 vs. 5.5 +/- 0.5 mmol/kg wet weight; P less than 0.001). These results indicate that proximal tubular Na/K-ATPase activity is enhanced in the hyperfiltration phase of diabetes mellitus. Since, however, intracellular Na concentration is increased under these conditions, it may be inferred that apical Na entry into proximal tubular cells is stimulated beyond the rate of basal exit during the initial development of hyperfiltration. The reasons for these alterations in cellular Na transport are unclear but similar changes have been implicated in the pathogenesis of cell growth. PMID:1645862

  20. Two-Dimensional Sensor Integration Using Resonant Proximity Connector

    E-print Network

    Shinoda, Hiroyuki

    Two-Dimensional Sensor Integration Using Resonant Proximity Connector -Basic Technology propose "Resonant Proximity Connector (RPC)" that enables non-contact (proximity) connection of the sensor without individual wires. In this paper, we propose "Resonant Proximity Connector (RPC)" that enables non

  1. Proximity-induced unconventional superconductivity in topological insulators

    NASA Astrophysics Data System (ADS)

    Black-Schaffer, Annica; Balatsky, Alexander

    2014-03-01

    We study proximity-induced superconducting pairing in a three-dimensional topological insulator - superconductor hybrid structure for superconductors with different pairing symmetries. The Dirac surface state in the topological insulator gives rise to a coupling between spin-singlet and spin-triplet pairing amplitudes as well as pairing that is odd in frequency for p-wave superconductors. We also find that all superconductors induce pairing that is odd in both frequency and orbital (band) index, with a complete reciprocity between pairing in orbital index and frequency. We show that the different induced pairing amplitudes significantly modify the density of states in the TI surface layer. We acknowledge support from the Swedish Research Council (VR), the European Research Council (ERC), US DoE Basic Energy Sciences, and Center for Integrated Nanotechnologies (contract DE-AC52-06NA25396).

  2. Safety limits for a firefighter proximity suit.

    PubMed

    Reischl, U; Reischl, P

    1978-07-01

    A standard one-piece firefighter proximity suit (jumpsuit style) was tested for heat accumulation and hood compartment ventilation. Large increases in temperature of the skin and hood compartmental air were recorded. Oxygen and carbon dioxide were monitored and hypoxic conditions found. Using the O2 and CO2 data, mathematical regression analyses were performed to predict the time exposures allowed for firemen entering various ambient atmospheric conditions. The short permissible exposure periods predicted for the proximity suit suggests limited usefulness and the need for immediate improvements in the design of the suit. PMID:696611

  3. Infrared-Proximity-Sensor Modules For Robot

    NASA Technical Reports Server (NTRS)

    Parton, William; Wegerif, Daniel; Rosinski, Douglas

    1995-01-01

    Collision-avoidance system for articulated robot manipulators uses infrared proximity sensors grouped together in array of sensor modules. Sensor modules, called "sensorCells," distributed processing board-level products for acquiring data from proximity-sensors strategically mounted on robot manipulators. Each sensorCell self-contained and consists of multiple sensing elements, discrete electronics, microcontroller and communications components. Modules connected to central control computer by redundant serial digital communication subsystem including both serial and a multi-drop bus. Detects objects made of various materials at distance of up to 50 cm. For some materials, such as thermal protection system tiles, detection range reduced to approximately 20 cm.

  4. Proximal femoral fractures: some determinants of outcome

    Microsoft Academic Search

    I F Greatorex; A C Gibbs

    1988-01-01

    We identified 226 proximal femoral fractures prospectively in people aged over 60 years during one year in Stockport (population approximately 289,000). Our objective was to examine the association between primary treatment and outcome 6 months after the fracture using multivariate regression models. Higher haemoglobin concentrations and mental test scores on admission to hospital were associated with lower fatality within 6

  5. Hybrid extragradient proximal algorithm coupled with parametric ...

    E-print Network

    In order to solve (P) we can use the classical proximal point algorithm, PPA for short: given x0 ? H, and a ..... Proof. Fix any u ? H, using Lemma 2.2 and the inclusion gk ? ??k fk(zk), we have ...... n an euclidean space and let ?k ? 0, uk ? E.

  6. A proximate dynamics model for data mining

    Microsoft Academic Search

    Yunfei Yin

    2009-01-01

    Many association rules with low supports and high confidence are commonly not convincing, so how to enhance the conviction of such rules is a big issue. In this paper, we explore the dynamics features of the domain dataset, and by predefining some dynamics parameters (as priori knowledge), we construct a proximate dynamics model for data mining so as to enhance

  7. Hybrid Repair of Proximal Subclavian Artery Aneurysm

    PubMed Central

    Morimoto, Kazuki; Fukuda, Tetsuya; Iba, Hiroshi; Tanaka, Hiroshi; Sasaki, Hiroaki; Minatoya, Kenji; Kobayashi, Junjiro

    2015-01-01

    Objective: Conventional open repair for proximal subclavian artery aneurysms (SCAAs) requires cardiopulmonary bypass. However, patients with proximal SCAA can be treated with hybrid repair. Methods: Between 2007 and 2012, we performed hybrid repair to treat six consecutive patients with proximal SCAA (three left SCAAs, one right aberrant SCAA, two right SCAAs). Their median age was 73.5 [70–87] years, and the size of their aneurysm was 33.5 [30–45] mm. Thoracic endovascular aneurysm repair (TEVAR) only was used for one patient with left SCAA, TEVAR and supra-aortic bypass for two with left SCAA and one with right aberrant SCAA, and endovascular repair with reconstruction of the vertebral artery using the saphenous vein graft (SVG) for two with right SCAA. Results: The follow-up duration was 3.7 [0.2–6.8] years. There was no 30-day mortality and only one early complication consisting of a minor stroke after TEVAR for shaggy aorta. Two late deaths occurred, one caused by cerebral infarction due to occlusion of SVG to the dominant vertebral artery 2 months after the operation and the other by aortic dissection 5 years postoperatively. Conclusions: Hybrid repair can be a less-invasive alternative for proximal SCAA. Revascularization of neck vessels and TEVAR should be performed very carefully to prevent neurologic complications.

  8. Goal-Proximity Decision-Making

    ERIC Educational Resources Information Center

    Veksler, Vladislav D.; Gray, Wayne D.; Schoelles, Michael J.

    2013-01-01

    Reinforcement learning (RL) models of decision-making cannot account for human decisions in the absence of prior reward or punishment. We propose a mechanism for choosing among available options based on goal-option association strengths, where association strengths between objects represent previously experienced object proximity. The proposed…

  9. Proximal femoral anatomy of omomyiform primates

    Microsoft Academic Search

    Peter Schmid

    1996-01-01

    Compared to the adapid primates, the limb skeleton of omomyiforms is only poorly represented. With the discovery of some new material, the proximal femur is now known in several taxa, including representatives from both of the recognized families. We describe the femur of a very small North American omomyid from the Bridger formation (middle Eocene) and compare its anatomy with

  10. Interpersonal Violence between College Students: Proximal Influences.

    ERIC Educational Resources Information Center

    Marcus, Robert; Reio, Thomas; Kessler, Lauren; Cutler, Kelley; Fleury, John

    This paper presents the results of a 3 year study on violence between students at the University of Maryland. The study was designed to: (1) describe the prevalence of fighting between students; (2) analyze, by gender, students' description of their most recent physical fight with another for proximal influences on these altercations; (3) analyze…

  11. Properties of Carbon Nanotubule Proximal Probe Tips

    Microsoft Academic Search

    Ajay Garg; Susan B. Sinnott

    1998-01-01

    Carbon nanotubules make novel proximal probe tips due to their small size and unique mechanical and electrical properties. We have performed molecular dynamics simulations to better understand the mechanisms by which nanotubules deformed during tip crashes or nanometer-scale indentations of diamond and graphine surfaces. The reactive empirical bond order potential for hydrocarbons parameterized by Brenner is used in the simulations.

  12. On target tracking with binary proximity sensors

    Microsoft Academic Search

    Wooyoung Kim; Kirill Mechitov; Jeung-yoon Choi; Soo Kyung Ham

    2005-01-01

    We consider the use of binary proximity sensors for tracking targets. Such sensors provide only 1-bit information regarding a target's presence or absence in their vicinity, albeit with less than 100% reliability. A novel tracking method employing such binary sensors is proposed and its performance in different deployment scenarios evaluated. For a given target, the method utilizes the sensor outputs

  13. Administration of atrial natriuretic factor inhibits sodium-coupled transport in proximal tubules.

    PubMed Central

    Hammond, T G; Yusufi, A N; Knox, F G; Dousa, T P

    1985-01-01

    The newly discovered peptides extracted from cardiac atria, atrial natriuretic factors (ANFs), when administered parenterally cause renal hemodynamic changes and natriuresis. The nephron sites and cellular mechanism accounting for profound increase in Na+ excretion in response to ANFs are not yet clarified. In the present study we investigated whether synthetic ANF peptide alters the reabsorption of Na+ and reabsorption of solutes cotransported with Na+ in the proximal tubules of rats. Synthetic ANF peptide consisting of 26 amino acids, 4 micrograms/kg body wt/h, or vehicle in controls, was infused to surgically thyroparathyroidectomized anesthetized rats. After determination of the fractional excretion (FE) of electrolytes (Na+, K+, Pi, Ca2+, Mg2+, HCO3), the kidneys were removed and luminal brush border membrane vesicles (BBMVs) were prepared from renal cortex. Solute transport was measured in BBMVs by rapid filtration techniques. Infusion of ANF peptide increased FENa, FEPi, and FEHCO3; but FECa, FEK, and FEMg were not changed. The increase in FENa was significantly correlated, on the one hand, with increase of FEPi (r = 0.9, n = 7; P less than 0.01) and with increase of FEHCO3 (r = 0.89, n = 7; P less than 0.01). On the other hand, FENa did not correlate with FEK, FECa, or with FEMg. The Na+ gradient-dependent uptake of Pi by BBMVs prepared from renal cortex of rats receiving ANF infusion was significantly (P less than 0.05) decreased (-25%), whereas the Na+ gradient-dependent uptake of L-[3H]proline and of D-[3H]glucose or the diffusional uptake of 22Na+ were not changed. ANF-elicited change in FEPi showed a close inverse correlation with decrease of Na+-dependent Pi uptake by BBMVs isolated from infused rats (r = 0.99, n = 7; P less than 0.001). Direct addition of ANF to BBMVs in vitro did not change the Na+ gradient-dependent Pi uptake. In rats infused with ANF, the rate of amiloride-sensitive Na+-H+ exchange across the brush border membrane (BBM) was significantly (P less than 0.05) decreased (-40%), whereas the diffusional 22Na+ uptake (0.5 min) and the equilibrium (120 min) uptake of 22Na+ were not changed. The inhibition of Na+-H+ exchange after ANF was likely due to alteration of the BBM antiporter itself, in that the H+ conductance of BBMVs was not increased. We conclude that synthetic ANF (a) decreases tubular Na+ reabsorption linked to reabsorption of HCO3 in proximal tubules, and (b) inhibits proximal tubular reabsorption of Pi coupled to Na+ reabsorption, independent of secretion and/or action of parathyroid hormone or calcitonin. These ANF effects are associated with inhibition of Na+-Pi synport and of Na+-H+ antiport in luminal BBMs. Our findings document that inhibition of Na+-coupled transport processes in proximal tubules is an integral part of the renal response to ANF. PMID:2989338

  14. Modeling Proximal Tubule Cell Homeostasis: Tracking Changes in Luminal Flow

    Microsoft Academic Search

    Alan M. Weinstein; Eduardo D. Sontag

    2009-01-01

    During normal kidney function, there are routinely wide swings in proximal tubule fluid flow and proportional changes in Na+ reabsorption across tubule epithelial cells. This “glomerulotubular balance” occurs in the absence of any substantial change\\u000a in cell volume, and is thus a challenge to coordinate luminal membrane solute entry with peritubular membrane solute exit.\\u000a In this work, linear optimal control

  15. Proximal tubular cell sodium concentration in early diabetic nephropathy assessed by electron microprobe analysis

    Microsoft Academic Search

    Carol A. Pollock; Michael J. Field; Thor E. Bostrom; Marlen Dyne; Akos Z. Gyory; David J. H. Cockayne

    1991-01-01

    Electron microprobe X-ray analysis techniques were employed in order to assess the changes that occur in proximal tubular cell sodium concentration during the hyperfiltration phase of early diabetes mellitus induced by streptozotocin in Sprague Dawley rats. Intracellular rubidium accumulation following intravenous infusion of rubidium chloride was used as a marker of basolateral Na\\/K-ATPase activity. The diabetic animals studied had a

  16. Characteristics of He II Proximity Profiles

    NASA Astrophysics Data System (ADS)

    Zheng, Wei; Syphers, David; Meiksin, Avery; Kriss, Gerard A.; Schneider, Donald P.; York, Donald G.; Anderson, Scott F.

    2015-06-01

    The proximity profile in the spectra of z? 3 quasars, where fluxes extend blueward of the He ii Ly? wavelength 304 (1+z) Å, is one of the most important spectral features in the study of the intergalactic medium (IGM). Based on the Hubble Space Telescope spectra of 24 He ii quasars, we find that the majority of them display a proximity profile, corresponding to an ionization radius as large as 20 Mpc in the source's rest frame. In comparison with those in the H i spectra of the quasars at z ? 6, the He ii proximity effect is more prominent and is observed over a considerably longer period of reionization. The He ii proximity zone sizes decrease at higher redshifts, particularly at z\\gt 3.3. This trend is similar to that for H i, signaling an onset of He ii reionization at z? 4. For quasar SDSS1253+6817 (z = 3.48), the He ii absorption trough displays a gradual decline and serves as a good case for modeling the He ii reionization. To model such a broad profile requires a quasar radiation field whose energy distribution between 4 and 1 Rydberg is considerably harder than normally assumed. The UV continuum of this quasar is indeed exceptionally steep, and the He ii ionization level in the quasar vicinity is higher than the average level in the IGM. These results are evidence that a very hard EUV continuum from this quasar produces a large ionized zone around it. Distinct exceptions are the two brightest He ii quasars at z ? 2.8, for which no significant proximity profile is present, probably implying that they are very young.

  17. Secreted frizzled-related protein-4 reduces sodium–phosphate co-transporter abundance and activity in proximal tubule cells

    Microsoft Academic Search

    Theresa J. Berndt; Bernhard Bielesz; Theodore A. Craig; Peter J. Tebben; Desa Bacic; Carsten A. Wagner; Stephen O’Brien; Susan Schiavi; Jurg Biber; Heini Murer; Rajiv Kumar

    2006-01-01

    The phosphatonin, secreted frizzled-related protein-4 (sFRP-4), induces phosphaturia and inhibits 25-hydroxyvitamin D 1?-hydroxylase activity normally induced in response to hypophosphatemia. To determine the mechanism by which sFRP-4 alters renal phosphate (Pi) transport, we examined the effect of sFRP-4 on renal brush border membrane (BBMV) Na+-dependent Pi uptake, and the abundance and localization of the major Na+–Pi-IIa co-transporter in proximal tubules

  18. Changes in Sodium or Glucose Filtration Rate Modulate Expression of Glucose Transporters in Renal Proximal Tubular Cells of Rat

    Microsoft Academic Search

    S. Vestri; M. M. Okamoto; H. S. de Freitas; R. Aparecida dos Santos; M. T. Nunes; M. Morimatsu; J. C. Heimann; U. F. Machado

    2001-01-01

    .   Renal glucose reabsorption is mediated by luminal sodium-glucose cotransporters (SGLTs) and basolateral facilitative glucose\\u000a transporters (GLUTs). The modulators of these transporters are not known, and their substrates glucose and Na+ are potential candidates. In this study we examined the role of glucose and Na+ filtration rate on gene expression of glucose transporters in renal proximal tubule. SGLT1, SGLT2, GLUT1

  19. Chloride transport across the basolateral cell membrane of the Necturus proximal tubule: Dependence on bicarbonate and sodium

    Microsoft Academic Search

    W. B. Guggino; E. L. Boulpaep; G. Giebisch

    1983-01-01

    Summary The transport of chloride across theNecturus proximal tubule cell was studied in the doubly-perfused kidney using conventional, chloride-sensitive and pH-sensitive microelectrodes. Lowering chloride activity in the basolateral solution results in a reduction in intracellular Cl- activity (aCli). This reduction inaCli is inhibited by removing either HCO3- or Na+ from the perfusion solution, indicating that both HCO3- and Na+ are

  20. H + extrusion by an apical vacuolar-type H + ATPase in rat renal proximal tubules

    Microsoft Academic Search

    Z. Zimolo; M. H. Montrose; H. Murer

    1992-01-01

    The activity of Na+\\/H+-exchange and H+-ATPase was measured in the absence of CO2\\/HCO3 by microfluorometry at the single cell level in rat proximal tubules (superficial S1\\/S2 segments) loaded with BCECF [2'7'-bis(carboxyethyl)5-6-carboxyfiuorescein-acetoxymethylester]. Intracellular pH (pHi) was lowered by a NH4Cl-prepulse technique. In the absence of Na+ in the superfusion solutions, pHi recovered from the acid load by a mechanism inhibited by

  1. Characterization of glucose transport by cultured rabbit kidney proximal convoluted and proximal straight tubule cells

    Microsoft Academic Search

    Pedro L. Del Valle; Anna Trifillis; Charles E. Ruegg; Andrew S. Kane

    2002-01-01

    Summary  Rabbit kidney proximal convoluted tubule (RPCT) and proximal straight tubule (RPST) cells were independently isolated and\\u000a cultured. The kinetics of the sodium-dependent glucose transport was characterized by determining the uptake of the glucose\\u000a analog alpha-methylglucopyranoside. Cell culture and assay conditions used in these experiments were based on previous experiments\\u000a conducted on the renal cell line derived from the whole kidney

  2. Comparison of outcomes of percutaneous coronary intervention on proximal versus non-proximal left anterior descending coronary artery, proximal left circumflex, and proximal right coronary artery: A cross-sectional study

    PubMed Central

    Alidoosti, Mohammad; Salarifar, Mojtaba; Zeinali, Ali Mohammad Haji; Kassaian, Seyed Ebrahim; Dehkordi, Maria Raissi

    2007-01-01

    Background Previous studies have shown that lesions in proximal left anterior descending coronary artery (LAD) may develop more restenosis after balloon angioplasty than lesions in other coronary segments. However, stenting seems to have reduced this gap. In this study, we compared outcomes of percutaneous coronary intervention (PCI) on proximal LAD versus proximal left circumflex (LCX) or right coronary artery (RCA) and proximal versus non-proximal LAD. Methods From 1737 patients undergoing PCI between March 2004 and 2005, those with cardiogenic shock, primary PCI, total occlusions, and multivessel or multi-lesion PCI were excluded. Baseline characteristics and in-hospital outcomes were compared in 408 patients with PCI on proximal LAD versus 133 patients with PCI on proximal LCX/RCA (study I) and 244 patients with PCI on non-proximal LAD (study II). From our study populations, 449 patients in study I and 549 patients in study II participated in complete follow-up programs, and long-term PCI outcomes were compared within these groups. The statistical methods included Chi-square or Fisher's exact test, student's t-test, stratification methods, multivariate logistic regression and Cox proportional hazards model. Results In the proximal LAD vs. proximal LCX/RCA groups, smoking and multivessel disease were less frequent and drug-eluting stents were used more often (p = 0.01, p < 0.001, and p < 0.001, respectively). Patients had longer and smaller-diameter stents (p = 0.009, p < 0.001, respectively). In the proximal vs. non-proximal LAD groups, multivessel disease was less frequent (p = 0.05). Patients had larger reference vessel diameters (p < 0.001) and were more frequently treated with stents, especially direct stenting technique (p < 0.001). Angiographic success rate was higher in the proximal LAD versus proximal LCX/RCA and non-proximal LAD groups (p = 0.004 and p = 0.05, respectively). In long-term follow-up, major adverse cardiac events showed no difference. After statistical adjustment for significant demographic, angiographic or procedural characteristics, long-term PCI outcomes were still similar in the proximal LAD versus proximal LCX/RCA and non-proximal LAD groups. Conclusion Despite the known worse prognosis of proximal LAD lesions, in the era of stenting, our long-term outcomes were similar in patients with PCI on proximal LAD versus proximal LCX/RCA and non-proximal LAD. Furthermore, we had better angiographic success rates in patients with PCI on proximal LAD. PMID:17335586

  3. Regulation of Na + \\/H + exchange in opossum kidney cells by parathyroid hormone, cyclic AMP and phorbol esters

    Microsoft Academic Search

    Corinna Helmle-Kolb; Marshall Ho Montrose; Gerti Stange; Heini Murer

    1990-01-01

    Parathyroid hormone (PTH) controls two proximal tubular brush border membrane transport systems, Na+\\/phosphate co-transport and Na+\\/H+ exchange. In OK cells, a cell line with proximal tubular transport characteristics, PTH acts via kinase C and kinase A activation to inhibit Na+\\/phosphate co-transport [6, 8, 9, 19, 22]. In the present study, we show that PTH inhibits Na+\\/H+ exchange and that this

  4. Proximity and Investment: Evidence from Plant-Level Data

    E-print Network

    Giroud, Xavier

    Proximity to plants makes it easier for headquarters to monitor and acquire information about plants. In this article, I estimate the effects of headquarters’ proximity to plants on plant-level investment and productivity. ...

  5. Proximity Services Supporting Network Virtual Memory in Mobile Devices

    E-print Network

    Bogliolo, Alessandro

    Proximity Services Supporting Network Virtual Memory in Mobile Devices Emanuele Lattanzi Andrea digital assistants, cell-phones or sensor nodes are typically memory constrained devices. This limitation Management, Measurement, Performance Keywords Proximity service, Mobility management, Network swap- ping

  6. The Proximity Toolkit: Prototyping Proxemic Interactions in Ubiquitous Computing Ecologies

    E-print Network

    Greenberg, Saul

    to access proxemic information from sensors. Our Proximity Toolkit solves this problem. It simplifies the ex mobile phones, tablet and desktop computers, information appliances, and large interactive surfaces1 The Proximity Toolkit: Prototyping Proxemic Interactions in Ubiquitous Computing Ecologies

  7. Proximity effects correction in real time

    NASA Astrophysics Data System (ADS)

    Jedrasik, Piotr

    1999-06-01

    A method for the proximity effects correction in electron beam lithography for layouts with critical dimensions below 180 nm is proposed. A parallel processing system based on an artificial neural networks is suggested as a solution to the problem. The algorithm for the learning vector generation is based on a discrete iterative regularization. Several results of the correction process for different test layouts are presented. Error analysis of the error measure is presented. The difference between the target dose and the doses deposited in each exel after the correction process is smaller than 5 percent. As a hardware implementation of the real time proximity effects corrector the radial basis functions neural system is proposed. Simulations of the Gaussian synapse cell have been done. Results of our simulations assure that our neurocorrector can precompensate for one exel from the layout in less than 60 ns.

  8. Treatment of proximal vertebral artery disease.

    PubMed

    Shutze, William; Gierman, Joshua; McQuade, Karen; Pearl, Gregory; Smith, Bertram

    2014-04-01

    Vertebral arterial disease (VAD) is a less commonly recognized and treated source of cerebrovascular ischemia compared with carotid artery disease. Patients are often referred for treatment after they have developed symptoms in the form of transient ischemic attacks or had a posterior hemispheric stroke. Traditional treatment of VAD has been surgical. More recently, endovascular treatment of VAD has been utilized. We performed a retrospective review of our institutional experience in treating VAD from 2001 to 2010. For treatment of proximal VAD, perioperative morbidity is lower for the endovascular group than for the surgical group, but six-week mortality was higher for the endovascular group. Complete resolution of symptoms occurred more frequently with surgery than with endovascular therapy. Therefore surgical reconstruction appears to be preferable to angioplasty and stenting for treatment of proximal vertebral artery occlusive disease. PMID:23518836

  9. Goal-proximity decision-making.

    PubMed

    Veksler, Vladislav D; Gray, Wayne D; Schoelles, Michael J

    2013-01-01

    Reinforcement learning (RL) models of decision-making cannot account for human decisions in the absence of prior reward or punishment. We propose a mechanism for choosing among available options based on goal-option association strengths, where association strengths between objects represent previously experienced object proximity. The proposed mechanism, Goal-Proximity Decision-making (GPD), is implemented within the ACT-R cognitive framework. GPD is found to be more efficient than RL in three maze-navigation simulations. GPD advantages over RL seem to grow as task difficulty is increased. An experiment is presented where participants are asked to make choices in the absence of prior reward. GPD captures human performance in this experiment better than RL. PMID:23551486

  10. Produre: A Novel Proximity Discovery Mechanism in Location Tagging System

    Microsoft Academic Search

    Jianbin Hu; Yonggang Wang; Tao Yang; Zhi Guan; Nike Gui; Zhong Chen

    \\u000a Proximity discovery is a very interesting and useful technique which helps a user to find out his proximities who have the\\u000a same or similar location with him during a certain period of time. However, current methods of discovering proximities are\\u000a difficult to adopt and vulnerable when wrong location tags are provided. This paper proposes Produre, a novel proximity discovery\\u000a mechanism

  11. Analytical parametrization of fusion barriers using proximity potentials

    SciTech Connect

    Dutt, Ishwar; Puri, Rajeev K. [Department of Physics, Panjab University, Chandigarh 160014 (India)

    2010-06-15

    Using the three versions of proximity potentials, namely proximity 1977, proximity 1988, and proximity 2000, we present a pocket formula for fusion barrier heights and positions. This was achieved by analyzing as many as 400 reactions with mass between 15 and 296. Our parametrized formula can reproduced the exact barrier heights and positions within an accuracy of +-1%. A comparison with the experimental data is also in good agreement.

  12. Rendezvous and proximity operations sensor candidates

    Microsoft Academic Search

    B. Kunkel; Ph. Hartl; W. Fehse

    1985-01-01

    As part of an ESA study, RVD and proximity operations on autonomous smart sensors for guidance between spacecraft are discussed. Measurement parameters for the sensors include range, range resolution, and range rate between 20 km and 0.1 m, and angular and lateral relative position between 20 km and 0.1 m. Sensors examined include a PRN Ku-band microwave range and attitude

  13. Space robotic system for proximity operations

    NASA Technical Reports Server (NTRS)

    Magnani, P. G.; Colomba, M.

    1989-01-01

    Key to an efficient accomplishment of space station servicing operations is the development of a scenario where the presence of man in space is well integrated with the capability of teleoperated and automatic robot system outside the stations. Results focusing on mission requirements, trajectory sequences, propulsion subsystem features, and manipulative kit characteristics relevant to proximity servicing during a Man Tended Free Flyers Robotic Mission (MTFF-RM) are illustrated.

  14. Proximity operations and docking sensor development

    Microsoft Academic Search

    Richard T. Howard; Thomas C. Bryan; Linda L. Brewster; J. E. Lee

    2009-01-01

    The next generation advanced video guidance sensor (NGAVGS) has been under development for the last three years as a long-range proximity operations and docking sensor for use in an Automated Rendezvous and Docking (AR&D) system. The first autonomous rendezvous and docking in the history of the U.S. Space Program was successfully accomplished by Orbital Express, using the Advanced Video Guidance

  15. Links between soil modelling and proximal sensing

    NASA Astrophysics Data System (ADS)

    Aitkenhead, Matt; McBratney, Alex; Minasny, Budiman

    2015-04-01

    Proximal sensing of soils can provide valuable information for soil modelling, by providing baseline data and validating model predictions through direct observation of soil characteristics. A wide range of soil parameters can be estimated using proximal sensing of soils (PSS), often simultaneously using single hand-held systems, of which there are many types. The benefits for soil modelling include direct observation of modelled parameters, rapid assessment in field conditions and digital data acquisition, making the transfer of information to soil models relatively straightforward. This is an active area of development, with research into improved methods of field-based capture of soil parameters directly relevant for soil modelling. A number of challenges exist, including the removal of or accounting for the effects of field conditions (e.g. soil moisture and structure), and the development of libraries of data that will allow calibration models to be produced. We present an overview of PSS as it relates to soil modelling, including equipment types, calibration approaches, cloud-based processing, soil parameters and processes estimated using PSS, and opportunities and challenges for the future. We also identify and discuss the possibilities for integration of modelling and proximal sensing within precision agriculture/precision land management.

  16. Proximity effects in topological insulator heterostructures

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Guang; Zhang, Gu-Feng; Wu, Guang-Fen; Chen, Hua; Dimitrie, Culcer; Zhang, Zhen-Yu

    2013-09-01

    Topological insulators (TIs) are bulk insulators that possess robust helical conducting states along their interfaces with conventional insulators. A tremendous research effort has recently been devoted to Tl-based heterostructures, in which conventional proximity effects give rise to a series of exotic physical phenomena. This paper reviews our recent studies on the potential existence of topological proximity effects at the interface between a topological insulator and a normal insulator or other topologically trivial systems. Using first-principles approaches, we have realized the tunability of the vertical location of the topological helical state via intriguing dual-proximity effects. To further elucidate the control parameters of this effect, we have used the graphene-based heterostructures as prototypical systems to reveal a more complete phase diagram. On the application side of the topological helical states, we have presented a catalysis example, where the topological helical state plays an essential role in facilitating surface reactions by serving as an effective electron bath. These discoveries lay the foundation for accurate manipulation of the real space properties of the topological helical state in TI-based heterostructures and pave the way for realization of the salient functionality of topological insulators in future device applications.

  17. Management of proximal humerus fractures in adults

    PubMed Central

    Vachtsevanos, Leonidas; Hayden, Lydia; Desai, Aravind S; Dramis, Asterios

    2014-01-01

    The majority of proximal humerus fractures are low-energy osteoporotic injuries in the elderly and their incidence is increasing in the light of an ageing population. The diversity of fracture patterns encountered renders objective classification of prognostic value challenging. Non-operative management has been associated with good functional outcomes in stable, minimally displaced and certain types of displaced fractures. Absolute indications for surgery are infrequent and comprise compound, pathological, multi-fragmentary head-splitting fractures and fracture dislocations, as well as those associated with neurovascular injury. A constantly expanding range of reconstructive and replacement options however has been extending the indications for surgical management of complex proximal humerus fractures. As a result, management decisions are becoming increasingly complicated, in an attempt to provide the best possible treatment for each individual patient, that will successfully address their specific fracture configuration, comorbidities and functional expectations. Our aim was to review the management options available for the full range of proximal humerus fractures in adults, along with their specific advantages, disadvantages and outcomes. PMID:25405098

  18. Trajectories in Close Proximity to Asteroids

    NASA Technical Reports Server (NTRS)

    Scheeres, D. J.

    2000-01-01

    Spacecraft motion in close proximity to irregularly shaped, rotating bodies such as asteroids presents a unique dynamical environment as compared to most space missions. There are several fundamental novelties in this environment that spacecraft must deal with. These include the possibility of orbital instabilities that can act over very short time spans (on the order of hours for some systems), possible non-uniform rotation of the central gravity field, divergence of traditional gravity field representations when close to the asteroid surface, dominance of perturbing forces, an extremely large asteroid model parameter space that must be prepared for in the absence of reliable information, and the possibility of employing new and novel trajectory control techniques such as hovering and repeated landings on the asteroid surface. An overview of how these novelties impact the space of feasible close proximity operations and how different asteroid model properties will affect their implementation is given. In so doing, four fundamental types of close proximity operations will be defined. Listed in order of increasing technical difficulty these are: (1) close, stable orbits; (2) low-altitude flyovers; (3) landing trajectories; and (4) hovering trajectories. The feasibility and difficulty of implementing these operations will vary as a function of the asteroid shape, size, density, and rotation properties, and as a function of the spacecraft navigation capability. Additional information is contained in the original extended abstract.

  19. 16.1 INVESTIGATING DERECHO AND SUPERCELL PROXIMITY SOUNDINGS

    E-print Network

    1 16.1 INVESTIGATING DERECHO AND SUPERCELL PROXIMITY SOUNDINGS Jeffry S. Evans* NOAA accumulated a number of proximity soundings associated with both derechos and discrete supercells. It can and analyzed 110 proximity soundings near 67 derechos. The period of study was from 1983-1993, and cases were

  20. 16.1 INVESTIGATING DERECHO AND SUPERCELL PROXIMITY SOUNDINGS

    E-print Network

    Doswell III, Charles A.

    1 16.1 INVESTIGATING DERECHO AND SUPERCELL PROXIMITY SOUNDINGS Jeffry S. Evans* NOAA of convection, we have accumulated proximity soundings associated with both derechos and discrete supercells and analyzed 113 proximity soundings near 67 derechos. The period of study was 1983-1993, and cases were

  1. Acoustic proximity ranging in the presence of secondary echoes

    Microsoft Academic Search

    Xi Li; Renbiao Wu; Srihari Rasmi; Jian Li; Mark Sheplak

    2003-01-01

    Proximity ranging is very important in many applications. Ultrasonic sensors have proven to be very cost effective tools for this purpose. Most of the currently available time-of-flight based acoustic proximity ranging systems use the conventional matched filter based time delay estimation approaches to measure short distances between proximity objects. However, in the presence of strong and closely spaced secondary echoes,

  2. Cooperation in humans: competition between groups and proximate emotions

    E-print Network

    West, Stuart

    Cooperation in humans: competition between groups and proximate emotions Maxwell N. Burton with the idea that the level of cooperation can be influenced by proximate emotions, which vary with the degree; Economic game; Group competition; Proximate; Emotion; Anger; Guilt 1. Introduction Explaining cooperative

  3. Proximity and Interactive Learning in University-Firm Relationships

    ERIC Educational Resources Information Center

    Thune, Taran

    2009-01-01

    This paper addresses the question of whether proximity is always necessary for interactive learning, as proposed by recent European innovation theory. Recent research has provided a refined conceptualization of proximity, but there is little empirically-based knowledge about the actual role that proximity plays in relationships intended to foster…

  4. Multiplication-stimulating activity-induced alkalinization of canine renal proximal tubular cells

    SciTech Connect

    Mellas, J.; Gavin, J.R. III; Hammerman, M.R.

    1986-11-05

    The actions of a variety of polypeptide growth factors on isolated cells are thought to be initiated by stimulation of Na/sup +/-H/sup +/ exchange across the plasma membranes of the cells resulting in intracellular alkalinization. To determine whether insulin-like growth factors (IGFs) exert actions through such a mechanism, the authors incubated suspensions of canine renal proximal tubular segments with insulin or IGF I or with multiplication-stimulating activity (MSA)/IGF II. Changes in intracellular pH were detected by measurements of the distribution of (/sup 14/C)5,5-dimethoxazolidine-2,4-dione. Incubation of segments with 10/sup +9/ M MSA under conditions such that extracellular (Na/sup +/)> intracellular (Na/sup +/) effected intracellular alkalinization detectable within 1-2 min. Alkalinization was not observed under conditions where this gradient was not present. Alkalinization was not prevented by inclusion of 1mM 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid or 1 mM ouabain in incubations, but was inhibited by amiloride. Incubation of proximal tubular segments with as little as 10/sup +11/ M MSA effected intracellular alkalinization. Incubation with as much as 10/sup -6/ M insulin or IGF I did not. Our findings are consistent with an action of MSA/IGF II to stimulate Na/sup +/-H/sup +/ exchange across the plasma membrane of the renal proximal tubular cell. It is possible that the stimulation represents a mechanism by which actions of IGF II are initiated in growth factor-sensitive cells.

  5. Fractures in proximal spinal muscular atrophy

    Microsoft Academic Search

    Albert Fujak; Carsten Kopschina; Raimund Forst; Florian Gras; Lutz Arne Mueller; Jürgen Forst

    2010-01-01

    Introduction  Fractures are a common problem for patients with spinal muscular atrophy (SMA).\\u000a \\u000a \\u000a \\u000a Patients  A total of 131 patients with proximal SMA with an average age of 13.2 ± 9.2 years (0.7–65.6) were evaluated retrospectively.\\u000a In 60 patients 94 different fractures were observed. The group consisted of 11 patients with type Ib, 81 with type II, 33\\u000a with type IIIa, 4 with IIIb and 2

  6. Giant cell tumour of the proximal radius.

    PubMed

    Singh, A P; Mahajan, S; Singh, A P

    2009-11-01

    A 52-year-old Indian woman presented with a progressively increasing swelling and pain in the right elbow for the past eight months, which was not associated with trauma or constitutional symptoms. The patient was diagnosed to have Campanacci grade III giant cell tumour of the proximal radius, and was treated with above elbow amputation. The patient has not shown any recurrence after five years of follow-up. The case was reported because of its rarity and the unusual site of occurrence of the tumour. PMID:19960152

  7. Casimir forces beyond the proximity approximation

    E-print Network

    Bimonte, G; Jaffe, R L; Kardar, M

    2011-01-01

    The proximity force approximation (PFA) relates the interaction between closely spaced, smoothly curved objects to the force between parallel plates. Precision experiments on Casimir forces necessitate, and spur research on, corrections to the PFA. We use a derivative expansion for gently curved surfaces to derive the leading curvature modifications to the PFA. Our methods apply to any homogeneous and isotropic materials; here we present results for Dirichlet and Neumann boundary conditions and for perfect conductors. A Pad\\'e extrapolation constrained by a multipole expansion at large distance and our improved expansion at short distances, provides an accurate expression for the sphere-plate Casimir force at all separations.

  8. Space station proximity operations and window design

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1988-01-01

    On-orbit proximity operations (PROX-OPS) consist of all extravehicular activity (EVA) within 1 km of the space station. Because of the potentially large variety of PROX-OPS, very careful planning for space station windows is called for and must consider a great many human factors. The following topics are discussed: (1) basic window design philosophy and assumptions; (2) the concept of the local horizontal - local vertical on-orbit; (3) window linear dimensions; (4) selected anthropomorphic considerations; (5) displays and controls relative to windows; and (6) full window assembly replacement.

  9. Casimir forces beyond the proximity approximation

    NASA Astrophysics Data System (ADS)

    Bimonte, G.; Emig, T.; Jaffe, R. L.; Kardar, M.

    2012-03-01

    The proximity force approximation (PFA) relates the interaction between closely spaced, smoothly curved objects to the force between parallel plates. Precision experiments on Casimir forces necessitate, and spur research on, corrections to the PFA. We use a derivative expansion for gently curved surfaces to derive the leading curvature modifications to the PFA. Our methods apply to any homogeneous and isotropic materials; here we present results for Dirichlet and Neumann boundary conditions and for perfect conductors. A Padé extrapolation constrained by a multipole expansion at large distance and our improved expansion at short distances, provides an accurate expression for the sphere/plate Casimir force at all separations.

  10. Proximity Induced Exchange Splitting in Graphene

    NASA Astrophysics Data System (ADS)

    Su, Shanshan; Barlas, Yafis; Lake, Roger

    2015-03-01

    We perform an ab-initio study of the proximity effect in a two-dimensional (2D) heterostructure composed of graphene and a thin film ferromagnetic insulator (europium oxide, EuO). Two different structures are considered i) graphene on a EuO layer and ii) graphene sandwiched between two EuO layers. Both structures show two-fold degenerate low-energy bands at the ? point in the Brillouin zone, however, the former heterostructure shows a clear energy gap in the spectrum whereas the latter exhibits degenerate band crossings. The two different spectra result from a competition of proximity induced exchange splitting on the graphene sheet and sub-lattice mass induced due to the crystal field effect. Addition of spin-orbit coupling in the sandwiched structure indicates lifting of this two-fold degeneracy leading to band anti-crossings if the inversion symmetry perpendicular to the graphene plane is broken. This work was supported as part of the Spins and Heat in Nanoscale Electronic Systems (Spins) an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award #DE-SC0012670.

  11. Updated classification system for proximal humeral fractures.

    PubMed

    Mora Guix, José M; Pedrós, Juan Sala; Serrano, Alejandro Castaño

    2009-06-01

    Proximal humeral fractures can restrict daily activities and, therefore, deserve efficient diagnoses that minimize complications and sequels. For good diagnosis and treatment, patient characteristics, variability in the forms of the fractures presented, and the technical difficulties in achieving fair results with surgical treatment should all be taken into account. Current classification systems for these fractures are based on anatomical and pathological principles, and not on systematic image reading. These fractures can appear in many different forms, with many characteristics that must be identified. However, many current classification systems lack good reliability, both inter-observer and intra-observer for different image types. A new approach to image reading, following a well-designed set and sequence of variables to check, is needed. We previously reported such an image reading system. In the present study, we report a classification system based on this image reading system. Here we define 21 fracture characteristics and apply them along with classical Codman approaches to classify fractures. We base this novel classification system for classifying proximal humeral fractures on a review of scientific literature and improvements to our image reading protocol. Patient status, fracture characteristics and surgeon circumstances have been important issues in developing this system. PMID:19574487

  12. Updated Classification System for Proximal Humeral Fractures

    PubMed Central

    Guix, José M. Mora; Pedrós, Juan Sala; Serrano, Alejandro Castaño

    2009-01-01

    Proximal humeral fractures can restrict daily activities and, therefore, deserve efficient diagnoses that minimize complications and sequels. For good diagnosis and treatment, patient characteristics, variability in the forms of the fractures presented, and the technical difficulties in achieving fair results with surgical treatment should all be taken into account. Current classification systems for these fractures are based on anatomical and pathological principles, and not on systematic image reading. These fractures can appear in many different forms, with many characteristics that must be identified. However, many current classification systems lack good reliability, both inter-observer and intra-observer for different image types. A new approach to image reading, following a well-designed set and sequence of variables to check, is needed. We previously reported such an image reading system. In the present study, we report a classification system based on this image reading system. Here we define 21 fracture characteristics and apply them along with classical Codman approaches to classify fractures. We base this novel classification system for classifying proximal humeral fractures on a review of scientific literature and improvements to our image reading protocol. Patient status, fracture characteristics and surgeon circumstances have been important issues in developing this system. PMID:19574487

  13. Artificial Topological Superconductor by the Proximity Effect

    NASA Astrophysics Data System (ADS)

    Xu, Jin-Peng; Liu, Canhua; Wang, Mei-Xiao; Ge, Jianfeng; Liu, Zhi-Long; Yang, Xiaojun; Chen, Yan; Liu, Ying; Xu, Zhu-An; Gao, Chun-Lei; Qian, Dong; Zhang, Fu-Chun; Jia, Jin-Feng

    2014-05-01

    Topological superconductors (TSCs), featuring fully gapped bulk and gapless surface states as well as Majorana fermions, have potential applications in fault-tolerant topological quantum computing. Because TSCs are very rare in nature, an alternative way to study the TSC is to artificially introduce superconductivity into the surface states of a topological insulator through the proximity effect [X. L. Qi, T. L. Hughse, S. Raghu, and S. C. Zhang, Phys. Rev. Lett. 102, 187001 (2009); L. Fu and C. L. Kane, Phys. Rev. Lett. 100, 096407 (2008); J. Alicea, Rep. Prog. Phys. 75, 076501 (2012); C. W. J. Beenakker, Annu. Rev. Condens. Matter Phys. 4, 113 (2013)]. Here we report the experimental realization of the proximity effect-induced TSC in Bi2Te3 thin films grown on a NbSe2 substrate, as demonstrated by the density of states probed using scanning tunneling spectroscopy. We observed Abrikosov vortices and Andreev lower energy bound states on the surface of the topological insulator, with the superconducting coherence length depending on the film thickness and the magnetic field. These results also indicate that the topological surface states of Bi2Te3 thin films are superconducting and, thus, that the Bi2Te3/NbSe2 is an artificial TSC. The feasibility of fabricating a TSC with an individual Majorana fermion bound to a superconducting vortex for topological quantum computing is discussed.

  14. Carbon nanotube proximity influences rice DNA

    NASA Astrophysics Data System (ADS)

    Katti, Dinesh R.; Sharma, Anurag; Pradhan, Shashindra Man; Katti, Kalpana S.

    2015-07-01

    The uptake of carbon nanotubes (CNT) influences the output of plants, potentially through interactions between the DNA and CNTs. However, little is known about the changes in the plant DNA due to CNT proximity. We report changes in rice plant DNA in the proximity of single walled CNT (SWCNT) using molecular dynamics simulations. The DNA experiences breaking and forming of hydrogen bonds due to unzipping of Watson-Crick (WC) nucleobase pairs and wrapping onto SWCNT. The number of hydrogen bonds between water and DNA nucleobases decreases due to the presence of SWCNT. A higher number of guanine-cytosine (Gua-Cyt) WC hydrogen bonds break as compared to adenine-thymine (Ade-Thy), which suggests that Gua and Cyt bases play a dominant role in DNA-SWCNT interactions. We also find that changes to non-WC nucleobase pairs and van der Waals attractive interactions between WC nucleobase pairs and SWCNT cause significant changes in the conformation of the DNA.

  15. Parathyroid hormone decreases HCO3 reabsorption in the rat proximal tubule by stimulating phosphatidylinositol metabolism and inhibiting base exit.

    PubMed Central

    Pastoriza-Munoz, E; Harrington, R M; Graber, M L

    1992-01-01

    The mechanism of inhibition of HCO3 transport by parathyroid hormone (PTH) in the proximal tubule is not clearly defined. Previous studies in vitro have suggested that this effect is mediated via cAMP generation, which acts to inhibit Na/H exchange, resulting in cell acidification. To examine this question in vivo, intracellular pH (pHi) was measured in the superficial proximal tubule of the rat using the pH-sensitive fluoroprobes 4-methylumbelliferone (4MU) and 2',7'-bis(carboxyethyl)-(5, and 6)-carboxyfluorescein (BCECF). PTH was found to alkalinize the cell. This alkalinization suggested inhibition of basolateral base exit, which was confirmed by in situ microperfusion studies: lowering HCO3 in peritubular capillaries acidified the cell, an effect blunted by PTH. Removal of luminal Na promoted basolateral base entry, alkalinizing the cell. This response was also blunted by PTH. Readdition of luminal Na stimulated the luminal Na/H exchanger, causing an alkalinization overshoot that was partially inhibited by PTH. cAMP inhibited luminal H secretion but did not alkalinize the cell. Stimulation of phosphatidylinositol-bis-phosphate turnover by PTH was suggested by the effect to the hormone to increase cell Ca. Blocking the PTH-induced rise in cell Ca blunted the effect of the hormone to alkalinize the cell, as did inhibition of phosphatidylinositol breakdown. Furthermore, stimulation of protein kinase C by a phorbol ester and a diacylglycerol applied basolaterally alkalinized the cell and inhibited luminal H secretion. The findings indicate that both arms of the phosphatidylinositol-bis-phosphate cascade play a role in mediating the effect of PTH on the cell pH. The results are consistent with the view that PTH inhibits base exit in the proximal tubule by activation of the phosphatidylinositol cascade. The resulting alkalinization may contribute, with cAMP, to inhibit apical Na/H exchange and the PTH-induced depression of proximal HCO3 reabsorption. PMID:1314850

  16. Variation of trabecular architecture in proximal femur of postmenopausal women

    Microsoft Academic Search

    Maria-Grazia Ascenzi; Nicole Hetzer; Alexandre Lomovtsev; Robert Rude; Aurelia Nattiv; Angela Favia

    2011-01-01

    This investigation of microstructure in the human proximal femur probes the relationship between the parameters of the FRAX index of fracture risk and the parameters of bone microstructure. The specificity of fracture sites at the proximal femur raises the question of whether trabecular parameters are site-specific during post-menopause, before occurrence of fragility fracture. The donated proximal femurs of sixteen post-menopausal

  17. Optical proximity correction with hierarchical Bayes model

    NASA Astrophysics Data System (ADS)

    Matsunawa, Tetsuaki; Yu, Bei; Pan, David Z.

    2015-03-01

    Optical Proximity Correction (OPC) is one of the most important techniques in today's optical lithography based manufacturing process. Although the most widely used model-based OPC is expected to achieve highly accurate correction, it is also known to be extremely time-consuming. This paper proposes a regression model for OPC using a Hierarchical Bayes Model (HBM). The goal of the regression model is to reduce the number of iterations in model-based OPC. Our approach utilizes a Bayes inference technique to learn the optimal parameters from given data. All parameters are estimated by the Markov Chain Monte Carlo method. Experimental results show that utilizing HBM can achieve a better solution than other conventional models, e.g., linear regression based model, or non-linear regression based model. In addition, our regression results can be fed as the starting point of conventional model based OPC, through which we are able to overcome the runtime bottleneck.

  18. Ecology: the proximate cause of frog declines?

    PubMed

    Di Rosa, Ines; Simoncelli, Francesca; Fagotti, Anna; Pascolini, Rita

    2007-05-31

    Pounds et al. argue that global warming contributes to amphibian declines by encouraging outbreaks of the chytrid fungus Batrachochytrium dendrobatidis. Although our findings agree with the climate-linked epidemic hypothesis, this pathogen is probably not the only proximate factor in such cases: in the Trasimeno Lake area of Umbria in central Italy, for example, the water frog Rana lessonae first declined in the late 1990s, yet chytridiomycosis was not observed until 2003 (refs 5, 6). Here we show that the chytrid was common there throughout 1999-2002, in a previously unknown form that did not cause disease. We therefore think that the focus by Pounds et al. on a single pathogen is hard to justify because the host-parasite ecology is at present so poorly understood. PMID:17538572

  19. Eating Event Detection by Magnetic Proximity Sensing

    PubMed Central

    Li, Chengliu; Bai, Yicheng; Jia, Wenyan; Sun, Mingui

    2014-01-01

    Eating event detection is an important problem in automatic dietary study using a wearable computer, such as the eButton. In this work, we approach this detection problem based on the use of a small magnet marker attached to a finger and a miniature magnetometer installed within the eButton. Our experimental results indicate that our magnetic approach is effective when the distance between the marker and the wearable computer is within 12cm, and the range of detection is approximately 15cm. We also found that the proximity signal patterns corresponding to eating and other daily activities are different, which can be used to reduce the false detection rate. In addition, our approach is convenient, low-cost and energy efficient, suitable for practical applications. PMID:25342877

  20. Axial heterogeneity of sodium-bicarbonate cotransport in proximal straight tubule of rabbit kidney

    Microsoft Academic Search

    Y. Kondo; E. Friimter

    1987-01-01

    Intracellular microelectrodes were used to investigate rheogenic Na+(HCO3-)n cotransport in different segments of isolated proximal straight tubule (PST) of rabbit kidney. In the first portion (S2 segment) the peritubular cell membrane potentialVb averaged -46.0, SE±1.3 mV (n=20), while in the terminal portion (S3 segment) it averaged -68.3, SE±2.5 mV (n=10). This difference may reflect different modes of anion permeation across

  1. Osteochondral fragmentation of the plantar/palmar proximal aspect of the proximal phalanx in racing horses.

    PubMed

    Whitton, R C; Kannegieter, N J

    1994-10-01

    The clinical presentation and outcome of treatment is presented for 26 cases of osteochondral fragmentation of the plantar/palmar proximal aspect of the proximal phalanx. Twenty-three were racing Standardbreds and three were racing Thoroughbreds. The most common reason for presentation was an inability to run straight at high speed. Only eight horses presented for lameness, although on examination 19 were lame. A positive flexion test was recorded in 90% of affected fetlock joints and effusion in 48%. Arthroscopic fragment removal was performed on 23 occasions in 21 horses and arthrotomy in one horse. Of the 16 horses that had returned to racing, 12 had improved their performance, while three showed no improvement, and one was retired for other reasons. In three horses refragmentation occurred after surgery, two of which had improved after initial arthroscopic removal. Degenerative changes within the fetlock joint were detected at surgery in eight horses. Of the four horses treated conservatively, one returned to its previous level of performance temporarily after intra-articular medication, one showed no improvement and two were still resting. Plantar/palmar osteochondral fragmentation of the proximal aspect of the first phalanx is a common cause of low-grade lameness in racing horses, and arthroscopic removal results in improvement in race performance in a high percentage of cases. PMID:7848178

  2. Proximity-dependent and proximity-independent trans-splicing in mammalian cells

    PubMed Central

    Viles, Kristi D.; Sullenger, Bruce A.

    2008-01-01

    Most human pre-mRNAs are cis-spliced, removing introns and joining flanking exons of the same RNA molecule. However, splicing of exons present on separate pre-mRNA molecules can also occur. This trans-splicing reaction can be exploited by pre-trans-splicing molecules (PTMs), which are incapable of cis-splicing. PTM-mediated trans-splicing has been utilized to repair mutant RNAs as a novel approach to gene therapy. Herein we explore how the site of PTM expression influences trans-splicing activity. We stably inserted a PTM expression cassette into the genome of HEK293 cells, generating clonal lines with single, unique insertion sites. We analyzed trans-splicing to the gene where the PTM was integrated, as well as genes neighboring these loci. We observed some pre-mRNAs only serve as substrates for trans-splicing when they are expressed in immediate proximity to the PTM expression site. The need for PTMs to be in close proximity with pre-mRNAs to trans-splice with them is consistent with the observation that pre-mRNA cis-splicing occurs cotranscriptionally. Interestingly, we identified several cellular pre-mRNAs in one localized area that serve as trans-splicing substrates irrespective of the PTM expression site. Thus, we find multiple cellular pre-mRNAs require PTM expression in close proximity to trans-splice while others do not. PMID:18441053

  3. Progressive increases in luminal glucose stimulate proximal sodium absorption in normal and diabetic rats.

    PubMed Central

    Bank, N; Aynedjian, H S

    1990-01-01

    The effect of progressive increases in intraluminal glucose concentration on proximal tubule sodium absorption was studied in normal and streptozotocin diabetic rats by microperfusion. Each tubule was perfused twice, with and without glucose added to the perfusion fluid. Net sodium and water absorption were markedly enhanced by 300-500 mg% intraluminal glucose in both normal and diabetic rats. Substituting the transported but nonmetabolized glucose analogue, alpha-methyl D-glucoside for glucose also resulted in marked stimulation of sodium absorption, whereas substituting bicarbonate and acetate for chloride in the perfusion solution inhibited the effect of glucose. These observations suggest that the stimulation of sodium absorption by glucose was mediated by the brush border Na/glucose cotransporter. Sodium concentration and osmolality were found to fall markedly to hypotonic levels when high glucose concentrations were in the perfusion fluid. This luminal hypotonicity may be an important driving force for proximal fluid absorption. In poorly controlled diabetes, high filtered glucose concentrations may lead to enhanced proximal sodium and water absorption, which could in turn contribute to volume expansion, hypertension, and renal hypertrophy. PMID:2365820

  4. Proximity Algorithms for Image Models: Denoising Charles A. Micchelli

    E-print Network

    Soatto, Stefano

    . This key strength is fully exploited in developing wavelet-based image denoising algorithms [5, 12, 20, 26Proximity Algorithms for Image Models: Denoising Charles A. Micchelli Lixin Shen Yuesheng Xu denoising. In this model, the denoised image is the proximity operator of the total variation evaluated

  5. Ontogeny of water transport in the rabbit proximal tubule

    Microsoft Academic Search

    Raymond Quigley; Jaap Mulder; Michel Baum

    2003-01-01

    Water transport across cell membranes is a fundamental biological problem. In the kidney, many nephron segments have mechanisms for transporting large quantities of water with minimal energy input. The proximal tubule reabsorbs two-thirds of the glomerular filtrate with a small transepithelial osmotic gradient as the driving force. In the adult proximal tubule, this is accomplished by the expression of aquaporin

  6. Palliation of proximal malignant biliary obstruction by endoscopic endoprosthesis insertion

    Microsoft Academic Search

    A A Polydorou; S R Cairns; J F Dowsett; A R Hatfield; P R Salmon; P B Cotton; R C Russell

    1991-01-01

    For four years up to December 1987, 190 patients (median age 73 years) with proximal malignant biliary obstruction were treated by endoscopic endoprosthesis insertion. Altogether 101 had cholangiocarcinoma, 21 gall bladder carcinoma, 20 local spread of pancreatic carcinoma, and 48 metastatic malignancy. Fifty eight patients had type I, 54 type II, and 78 type III proximal biliary strictures (Bismuth classification).

  7. Fingerprinting temporal networks of close-range human proximity

    E-print Network

    Barrat, Alain

    .barrat@cpt.univ-mrs.fr Abstract--Mobile devices and wearable sensors are making available records of human mobility and proximity specific aspects of human behavior, such as geographic mobility [1]­ [7], phone communications [8], email exchange or instant messaging [9]­[14], and even human mobility and proximity in indoor environments [15

  8. The Proximity Toolkit: Prototyping Proxemic Interactions in Ubiquitous Computing Ecologies

    E-print Network

    Greenberg, Saul

    is that developers find it challenging and tedious to ac- cess proxemic information from sensors. Our Proximity digital devices of varying size, e.g., personal mobile phones, tablet and desktop computers, informationThe Proximity Toolkit: Prototyping Proxemic Interactions in Ubiquitous Computing Ecologies ABSTRACT

  9. Behaviour Detection Using Bluetooth Proximity Muhammad Awais Azam 1, 2

    E-print Network

    Tokarchuk, Laurissa

    as an efficient short range sensor. In this paper we use Bluetooth proximity data to detect the repeated patterns Identification (RFID), motion sensors and tracking devices are being used to get the real time proximity and daily life data. In particular, devices like mobile phones provide a rich platform for diverse data

  10. Proximity and territory versus space in regional science

    Microsoft Academic Search

    O Crevoisier

    1996-01-01

    Empirical evidence tends to show that regional development occurs only in certain places. Therefore, one can ask the central question of the role of physical proximity in economic development processes. Economists try to answer this question through the concept of externalities, but this does not explain why certain externalities are linked with physical proximity. In this paper the author tries

  11. Voltage collapse proximity index determination using voltage phasors approach

    Microsoft Academic Search

    F. Gubina; B. Strmcnik

    1995-01-01

    In the paper, a “phasor concept” of voltage collapse proximity determination is presented. An adequate voltage proximity index is calculated based on the voltage phasor values only. Furthermore, an algorithm is derived which automatically detects the network transmission paths to the load nodes which are prone to voltage collapse due to additional real or reactive loading. The algorithm is tested

  12. A Proximal-Gradient Homotopy Method for the Sparse Least ...

    E-print Network

    2012-10-22

    e.g., O(nlog n) if A is a partial Fourier matrix. Proximal gradient .... problems, the total number of proximal gradient steps in our method can be much smaller than ...... By further splitting x ? ¯x1 on the left-hand side as (x ? ¯x)¯S 1 + (x ? ¯x)¯Sc.

  13. Proximity effect correction optimization considering fogging and loading effects compensation

    Microsoft Academic Search

    Seung-Hune Yang; Yo-Han Choi; Jong R. Park; Yong-Hoon Kim; Seong-Woon Choi; Jung-Min Sohn

    2002-01-01

    Recently, the interest in enhancement of critical dimension (CD) accuracy has been significantly increased to satisfy requirements of sub 100nm devices. Proximity effect correction becomes an indispensable choice to improve CD accuracy within local area, and fogging and loading effects compensation has been tried to enhance global CD uniformity. However, proximity effect correction (PEC) parameters obtained without considering additional exposure

  14. DEVELOPMENT OF VISION SKIN: A PROXIMITY AND IMAGING SENSOR

    E-print Network

    Chapman, Glenn H.

    . Further work in the sensor requires integration of the laser, and faster acquisition hardware and softwareDEVELOPMENT OF VISION SKIN: A PROXIMITY AND IMAGING SENSOR by Darren Edward Bergen B.A.Sc., Simon of Applied Science in Engineering Science Skin TITLE: A Proximity And Imaging Sensor Examining Committee

  15. Long-range superconducting proximity effect in polycrystalline Co nanowires

    SciTech Connect

    Kompaniiets, M.; Porrati, F.; Huth, M. [Physikalisches Institut, Goethe-University, 60438 Frankfurt am Main (Germany); Dobrovolskiy, O. V., E-mail: Dobrovolskiy@Physik.uni-frankfurt.de [Physikalisches Institut, Goethe-University, 60438 Frankfurt am Main (Germany); Department of Physics, V. Karazin National University, 61077 Kharkiv (Ukraine); Neetzel, C.; Brötz, J.; Ensinger, W. [Department of Materials Science, TU Darmstadt, 64287 Darmstadt (Germany)

    2014-02-03

    We report experimental evidence of a long-range superconducting proximity effect in polycrystalline Co nanowires in contact with a superconducting W-based floating electrode (inducer). For electrical resistance measurements, voltage leads were connected to the Co nanowire on both sides of the superconducting inducer at a distance of 7.2 ?m. We observed a 28% reduction of the nanowire resistance when sweeping the temperature below the inducer's transition temperature T{sub c} = 5.2 K. Our analysis of the resistance data shows that the superconducting proximity length in polycrystalline Co is as large as 1 ?m at 2.4 K, attesting to a long-range proximity effect. Moreover, this long-range proximity effect is insusceptible to magnetic fields up to 11 T, which is indicative of spin-triplet pairing. Our results provide evidence that magnetic inhomogeneity of the ferromagnet enlarges the spatial extend of the spin-triplet superconducting proximity effect.

  16. Long-range superconducting proximity effect in polycrystalline Co nanowires

    NASA Astrophysics Data System (ADS)

    Kompaniiets, M.; Dobrovolskiy, O. V.; Neetzel, C.; Porrati, F.; Brötz, J.; Ensinger, W.; Huth, M.

    2014-02-01

    We report experimental evidence of a long-range superconducting proximity effect in polycrystalline Co nanowires in contact with a superconducting W-based floating electrode (inducer). For electrical resistance measurements, voltage leads were connected to the Co nanowire on both sides of the superconducting inducer at a distance of 7.2 ?m. We observed a 28% reduction of the nanowire resistance when sweeping the temperature below the inducer's transition temperature Tc = 5.2 K. Our analysis of the resistance data shows that the superconducting proximity length in polycrystalline Co is as large as 1 ?m at 2.4 K, attesting to a long-range proximity effect. Moreover, this long-range proximity effect is insusceptible to magnetic fields up to 11 T, which is indicative of spin-triplet pairing. Our results provide evidence that magnetic inhomogeneity of the ferromagnet enlarges the spatial extend of the spin-triplet superconducting proximity effect.

  17. Renal transport of monocarboxylic acids. Heterogeneity of lactate-transport systems along the proximal tubule.

    PubMed Central

    Jørgensen, K E; Sheikh, M I

    1984-01-01

    The characteristics of D- and L-lactate transport in luminal-membrane vesicles derived from whole cortex, from the pars convoluta and from the pars recta of rabbit kidney proximal tubule were studied. It was found that uptake of both isomers in vesicles from whole cortex occurred by means of dual electrogenic transport systems, namely a low-affinity system and a high-affinity system. Uptake of both isomers in vesicles from the pars recta was strictly Na+-dependent and is mediated via a single high-affinity common transport system. Vesicles from the pars convoluta contained a cation-dependent but Na+-unspecific low-affinity common transport system for these compounds. The physiological importance of this system is briefly discussed. PMID:6508742

  18. Proximal metatarsal osteotomy in hallux valgus.

    PubMed

    Cedell, C A; Aström, M

    1982-12-01

    In order to obtain an optimal correction of hallux valgus and to prevent its recurrence, the authors have applied a surgical technique which combines a proximal valgus osteotomy of the first metatarsal bone with an excision of the pseudoexostosis and a distal soft tissue plasty at the first metatarsophalangeal joint. The procedure is based on an etiological theory regarding metatarsus primus varus as the primary cause of the deformity, which is in accordance with the opinion of many other authors. The osteotomy corrects the malposition of the first metatarsal bone thereby reducing the deformity and preventing its recurrence. The soft tissue plasty alleviates secondary contractures that prevent a full correction of the big toe. A series of 43 consecutive patients (46 feet) with a follow-up period of 5-44 months and extracted from a total number of 99 operated cases is presented. The result was excellent in 78 per cent, good in 11 per cent and poor in 11 per cent. The reason for a less than excellent result was almost always inadequate correction of the deformity, at the level of the first metatarsal bone, or the big toe, or both. PMID:7180392

  19. Optical Detection of the Superconducting Proximity Effect.

    NASA Astrophysics Data System (ADS)

    Roshchin, I. V.; Abeyta, A. C.; Kuchler, G.; Greene, L. H.; Dorsten, J. F.; Tanzer, T. A.; Bohn, P. W.

    1996-03-01

    We present the first observation of the superconducting proximity effect by an optical method. Raman analysis was done on highly n-doped (1.2×10^19cm-3) InAs through a thin high-quality, superconducting Nb film, grown by DC-magnetron sputtering directly on in-situ low-voltage ion-etched InAs substrates, thus providing a clean, minimally damaged interface. The resistively determined T_c's are 2.5K and 5.5K for 60Å and 100Å thick films respectively. The low-frequency (L_-) coupled plasmon-phonon mode, associated with the bulk InAs, appeares as a broad asymmetric peak at 221cm-1. The LO phonon mode, at 237cm-1, forbidden in the bulk, is associated with the 35Åthick surface charge accumulation region of InAs. The magnitude of the LO mode increases by more than 40% as the temperature is reduced from 10K to 1.8K, as Tc is crossed. The L- mode is not affected, and no frequency shift in either mode is observed within the resolution of the experiment. Supported by ^*DoE through MRL (DEFG02-91ER45439), ^NSF through MRL (NSF-DMR-89-20538), and ^ONR (N00014-93-1-1168).

  20. Semiconductor detectors with proximity signal readout

    SciTech Connect

    Asztalos, Stephen J. [XIA, LLC, Hayward, CA (United States)

    2014-01-30

    Semiconductor-based radiation detectors are routinely used for the detection, imaging, and spectroscopy of x-rays, gamma rays, and charged particles for applications in the areas of nuclear and medical physics, astrophysics, environmental remediation, nuclear nonproliferation, and homeland security. Detectors used for imaging and particle tracking are more complex in that they typically must also measure the location of the radiation interaction in addition to the deposited energy. In such detectors, the position measurement is often achieved by dividing or segmenting the electrodes into many strips or pixels and then reading out the signals from all of the electrode segments. Fine electrode segmentation is problematic for many of the standard semiconductor detector technologies. Clearly there is a need for a semiconductor-based radiation detector technology that can achieve fine position resolution while maintaining the excellent energy resolution intrinsic to semiconductor detectors, can be fabricated through simple processes, does not require complex electrical interconnections to the detector, and can reduce the number of required channels of readout electronics. Proximity electrode signal readout (PESR), in which the electrodes are not in physical contact with the detector surface, satisfies this need.

  1. Interactive orbital proximity operations planning system

    NASA Technical Reports Server (NTRS)

    Grunwald, Arthur J.; Ellis, Stephen R.

    1989-01-01

    An interactive, graphical proximity operations planning system was developed which allows on-site design of efficient, complex, multiburn maneuvers in the dynamic multispacecraft environment about the space station. Maneuvering takes place in, as well as out of, the orbital plane. The difficulty in planning such missions results from the unusual and counterintuitive character of relative orbital motion trajectories and complex operational constraints, which are both time varying and highly dependent on the mission scenario. This difficulty is greatly overcome by visualizing the relative trajectories and the relative constraints in an easily interpretable, graphical format, which provides the operator with immediate feedback on design actions. The display shows a perspective bird's-eye view of the space station and co-orbiting spacecraft on the background of the station's orbital plane. The operator has control over two modes of operation: (1) a viewing system mode, which enables him or her to explore the spatial situation about the space station and thus choose and frame in on areas of interest; and (2) a trajectory design mode, which allows the interactive editing of a series of way-points and maneuvering burns to obtain a trajectory which complies with all operational constraints. Through a graphical interactive process, the operator will continue to modify the trajectory design until all operational constraints are met. The effectiveness of this display format in complex trajectory design is presently being evaluated in an ongoing experimental program.

  2. Proximate industrial activity and psychological distress

    PubMed Central

    Downey, Liam; Jackson, James S.; Merrill, J. Bryce; Saint Onge, Jarron M.; Williams, David R.

    2009-01-01

    This paper examines the role that gender, occupational status, and family status play in moderating the effect of industrial activity on the psychological well-being of nearby residents. Using a unique spatial assessment of industrial activity and an environmental risk/social stressor framework in conjunction with individual-level data from the Detroit Area Study (DAS) and demographic data from the U.S. census, we find that residents of neighborhoods in close proximity to industrial activity report elevated levels of psychological distress compared to residents of neighborhoods removed from this type of activity. These influences are more pronounced among women but gender differences are also contingent upon occupational and family statuses. We show that specific combinations of work and family statuses make persons particularly vulnerable to the influence of this environmental stressor and women are two and a half times more likely than men to have these vulnerable statuses. This study makes an important contribution to the environmental health literature because it reminds researchers of the fundamental influence of social roles when examining the link between environmental risks and mental health. PMID:19444334

  3. Interactive orbital proximity operations planning system

    NASA Technical Reports Server (NTRS)

    Grunwald, Arthur J.; Ellis, Stephen R.

    1988-01-01

    An interactive graphical proximity operations planning system was developed, which allows on-site design of efficient, complex, multiburn maneuvers in a dynamic multispacecraft environment. Maneuvering takes place in and out of the orbital plane. The difficulty in planning such missions results from the unusual and counterintuitive character of orbital dynamics and complex time-varying operational constraints. This difficulty is greatly overcome by visualizing the relative trajectories and the relevant constraints in an easily interpretable graphical format, which provides the operator with immediate feedback on design actions. The display shows a perspective bird's-eye view of a Space Station and co-orbiting spacecraft on the background of the Station's orbital plane. The operator has control over the two modes of operation: a viewing system mode, which enables the exporation of the spatial situation about the Space Station and thus the ability to choose and zoom in on areas of interest; and a trajectory design mode, which allows the interactive editing of a series of way points and maneuvering burns to obtain a trajectory that complies with all operational constraints. A first version of this display was completed. An experimental program is planned in which operators will carry out a series of design missions which vary in complexity and constraints.

  4. Optical proximity correction with principal component regression

    NASA Astrophysics Data System (ADS)

    Gao, Peiran; Gu, Allan; Zakhor, Avideh

    2008-03-01

    An important step in today's Integrated Circuit (IC) manufacturing is optical proximity correction (OPC). In model based OPC, masks are systematically modified to compensate for the non-ideal optical and process effects of optical lithography system. The polygons in the layout are fragmented, and simulations are performed to determine the image intensity pattern on the wafer. Then the mask is perturbed by moving the fragments to match the desired wafer pattern. This iterative process continues until the pattern on the wafer matches the desired one. Although OPC increases the fidelity of pattern transfer to the wafer, it is quite CPU intensive; OPC for modern IC designs can take days to complete on computer clusters with thousands of CPU. In this paper, techniques from statistical machine learning are used to predict the fragment movements. The goal is to reduce the number of iterations required in model based OPC by using a fast and efficient solution as the initial guess to model based OPC. To determine the best model, we train and evaluate several principal component regression models based on prediction error. Experimental results show that fragment movement predictions via regression model significantly decrease the number of iterations required in model based OPC.

  5. Regulation of glomerulotubular balance. III. Implication of cytosolic calcium in flow-dependent proximal tubule transport.

    PubMed

    Du, Zhaopeng; Weinbaum, Sheldon; Weinstein, Alan M; Wang, Tong

    2015-04-15

    In the proximal tubule, axial flow (drag on brush-border microvilli) stimulates Na(+) and HCO3 (-) reabsorption by modulating both Na/H exchanger 3 (NHE3) and H-ATPase activity, a process critical to glomerulotubular balance. We have also demonstrated that blocking the angiotensin II receptor decreases baseline transport, but preserves the flow effect; dopamine leaves baseline fluxes intact, but abrogates the flow effect. In the current work, we provide evidence implicating cytosolic calcium in flow-dependent transport. Mouse proximal tubules were microperfused in vitro at perfusion rates of 5 and 20 nl/min, and reabsorption of fluid (Jv) and HCO3 (-) (JHCO3) were measured. We examined the effect of high luminal Ca(2+) (5 mM), 0 mM Ca(2+), the Ca(2+) chelator BAPTA-AM, the inositol 1,4,5-trisphosphate (IP3) receptor antagonist 2-aminoethoxydiphenyl borate (2-APB), and the Ca-ATPase inhibitor thapsigargin. In control tubules, increasing perfusion rate from 5 to 20 nl/min increased Jv by 62% and JHCO3 by 104%. With respect to Na(+) reabsorption, high luminal Ca(2+) decreased transport at low flow, but preserved the flow-induced increase; low luminal Ca(2+) had little impact; both BAPTA and 2-APB had no effect on baseline flux, but abrogated the flow effect; thapsigargin decreased baseline flow, leaving the flow effect intact. With respect to HCO3 (-) reabsorption, high luminal Ca(2+) decreased transport at low flow and mildly diminished the flow-induced increase; low luminal Ca(2+) had little impact; both BAPTA and 2-APB had no effect on baseline flux, but abrogated the flow effect. These data implicate IP3 receptor-mediated intracellular Ca(2+) signaling as a critical step in transduction of microvillous drag to modulate Na(+) and HCO3 (-) transport. PMID:25651568

  6. Long-term regulation of proximal tubule acid-base transporter abundance by angiotensin II.

    PubMed

    Turban, S; Beutler, K T; Morris, R G; Masilamani, S; Fenton, R A; Knepper, M A; Packer, R K

    2006-08-01

    In the proximal tubule, angiotensin II (Ang-II) regulates HCO(-)(3) reabsorption and H+ secretion by binding the type 1 Ang-II (AT1) receptor, stimulating Na(+)/HCO(-)(3) cotransport and Na(+)/H(+) exchange. Studies were carried out to determine if long-term changes in Ang-II receptor occupation alter the abundance of the basolateral Na(+)/HCO(-)(3) cotransporter (NBC1) or the apical membrane type 3 Na(+)/H(+) exchanger (NHE3). In the first set of experiments, rats eating a low-sodium diet were infused with the AT1 blocker, candesartan, or vehicle. In the second, lisinopril-infused rats were infused with either Ang II or vehicle. Transporter abundances were determined in whole kidney homogenates (WKH) and in brush border membrane (BBM) preparations by semiquantitative immunoblotting. Tissue distribution of transporters was assessed by immunocytochemistry. Blockade of the AT1 receptor by candesartan caused decreased abundance of NBC1 in WKH (59 +/- 9% of control; P<0.05) and Ang-II infusion increased abundance (130 +/- 7% of control; P<0.05). Changes in NBC1 in response to candesartan were confirmed immunohistochemically. Neither candesartan nor Ang II infusion affected the abundance of NHE3 in WKH or cortical homogenates. Candesartan decreased type 2 sodium-phosphate cotransporter abundance in both WKH (52 +/- 7% of control; P<0.05) and BBM (32 +/- 7% of control; P<0.05). Serum bicarbonate was decreased by candesartan and increased by Ang-II. Candesartan also decreased urinary ammonium excretion (P<0.05). The long-term effects of Ang-II in the proximal tubule may be mediated in part by regulation of NBC1 abundance, modifying bicarbonate reabsorption. PMID:16807546

  7. Lipotoxic disruption of NHE1 interaction with PI(4,5)P2 expedites proximal tubule apoptosis

    PubMed Central

    Khan, Shenaz; Abu Jawdeh, Bassam G.; Goel, Monu; Schilling, William P.; Parker, Mark D.; Puchowicz, Michelle A.; Yadav, Satya P.; Harris, Raymond C.; El-Meanawy, Ashraf; Hoshi, Malcolm; Shinlapawittayatorn, Krekwit; Deschênes, Isabelle; Ficker, Eckhard; Schelling, Jeffrey R.

    2014-01-01

    Chronic kidney disease progression can be predicted based on the degree of tubular atrophy, which is the result of proximal tubule apoptosis. The Na+/H+ exchanger NHE1 regulates proximal tubule cell survival through interaction with phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], but pathophysiologic triggers for NHE1 inactivation are unknown. Because glomerular injury permits proximal tubule luminal exposure and reabsorption of fatty acid/albumin complexes, we hypothesized that accumulation of amphipathic, long-chain acyl-CoA (LC-CoA) metabolites stimulates lipoapoptosis by competing with the structurally similar PI(4,5)P2 for NHE1 binding. Kidneys from mouse models of progressive, albuminuric kidney disease exhibited increased fatty acids, LC-CoAs, and caspase-2–dependent proximal tubule lipoapoptosis. LC-CoAs and the cytosolic domain of NHE1 directly interacted, with an affinity comparable to that of the PI(4,5)P2-NHE1 interaction, and competing LC-CoAs disrupted binding of the NHE1 cytosolic tail to PI(4,5)P2. Inhibition of LC-CoA catabolism reduced NHE1 activity and enhanced apoptosis, whereas inhibition of proximal tubule LC-CoA generation preserved NHE1 activity and protected against apoptosis. Our data indicate that albuminuria/lipiduria enhances lipotoxin delivery to the proximal tubule and accumulation of LC-CoAs contributes to tubular atrophy by severing the NHE1-PI(4,5)P2 interaction, thereby lowering the apoptotic threshold. Furthermore, these data suggest that NHE1 functions as a metabolic sensor for lipotoxicity. PMID:24531551

  8. Selection of proximal fusion level for degenerative scoliosis and the entailing proximal-related late complications

    PubMed Central

    Zhu, Yi; Wang, Kaifeng; Wang, Bo; Wang, Huimin; Jin, Zhaohui; Zhu, Zhenqi; Liu, Haiying

    2015-01-01

    Objective: To determine the optimal selection of proximal fusion level for degenerative scoliosis (DS) and investigate the long-term proximal-related complications. Methods: Profiles of 95 consecutive patients with DS who underwent posterior long instrumented fusion were analyzed retrospectively. Perioperative parameters were reviewed stratified into 3 groups according to the relationship between the upper instrumented vertebrae (UIV), horizontal vertebrae (HV) and upper end vertebrae (UEV), namely HV Group (UIV = HV or above), HV-UEV Group (UIV = between HV and UEV) and UEV Group (UIV = UEV or below) in coronal plane and 3 groups in sagittal plane according to segment levels. Clinical and radiographic parameters were studied statistically. Results: Average follow-up was 7.8 years (range, 5-13 years). HV Group showed a significant increase in operative time, intraoperative blood loss, postoperative in-bed time, and hospital stays. UEV Group showed greater average Cobb angle, AVT and DW. UEV Group showed significant increase in operative time, blood loss, postoperative in-bed time, and inpatient stay. All three groups showed significant improvement in ODI compared to baseline, while there was no significant difference in LL between three groups. Proximal-related late complications included recurrent junctional scoliosis in 4 cases and junctional kyphosis in 4 cases. Conclusions: Recurrent junctional scoliosis developed more commonly when the fusion was at or below the UEV, and fusion at L1 or L2 showed the highest incidence of junctional kyphosis. Long instrumented fusion to T11 or T12 appeared to be a reasonable alternative when the UIV was above UEV in DS.

  9. Giant proximity effect and critical opalescence in EuS

    NASA Astrophysics Data System (ADS)

    Charlton, Timothy; Ramos, Silvia; Quintanilla, Jorge; Suter, Andreas; Moodera, Jagadeesh

    2015-03-01

    The proximity effect is a type of wetting phenomenon where an ordered state, usually magnetism or superconductivity, ``leaks'' from one material into an adjacent one over some finite distance. For superconductors, the characteristic range is of the order of the coherence length, usually hundreds of nm. Nevertheless much longer, ``giant'' proximity effects have been observed in cuprate perovskite junctions. Such giant proximity effects can be understood by taking into account the divergence of the pairing susceptibility in the non-superconducting material when it is itself close to a superconducting instability: a superconducting version of critical opalescence. Since critical opalescence occurs in all second order phase transitions, giant proximity effects are expected to be general, therefor there must be a giant ferromagnetic proximity effect. Compared to its superconducting counterpart, the giant ferromagnetic proximity effect has the advantage that the order parameter (magnetization) can be observed directly. We have fabricated Co/EuS thin films and measured the magnetization profiles as a function of temperature using the complementary techniques of low energy muon relaxation and polarized neutron reflectivity. Details of the proximity effect near TCEuS will be presented.

  10. Hypospadias and Residential Proximity to Pesticide Applications

    PubMed Central

    Yang, Wei; Roberts, Eric M.; Kegley, Susan E.; Wolff, Craig; Guo, Liang; Lammer, Edward J.; English, Paul; Shaw, Gary M.

    2013-01-01

    BACKGROUND: Experimental evidence suggests pesticides may be associated with hypospadias. OBJECTIVE: Examine the association of hypospadias with residential proximity to commercial agricultural pesticide applications. METHODS: The study population included male infants born from 1991 to 2004 to mothers residing in 8 California counties. Cases (n = 690) were ascertained by the California Birth Defects Monitoring Program; controls were selected randomly from the birth population (n = 2195). We determined early pregnancy exposure to pesticide applications within a 500-m radius of mother’s residential address, using detailed data on applications and land use. Associations with exposures to physicochemical groups of pesticides and specific chemicals were assessed using logistic regression adjusted for maternal race or ethnicity and age and infant birth year. RESULTS: Forty-one percent of cases and controls were classified as exposed to 57 chemical groups and 292 chemicals. Despite >500 statistical comparisons, there were few elevated odds ratios with confidence intervals that excluded 1 for chemical groups or specific chemicals. Those that did were for monochlorophenoxy acid or ester herbicides; the insecticides aldicarb, dimethoate, phorate, and petroleum oils; and adjuvant polyoxyethylene sorbitol among all cases; 2,6-dinitroaniline herbicides, the herbicide oxyfluorfen, and the fungicide copper sulfate among mild cases; and chloroacetanilide herbicides, polyalkyloxy compounds used as adjuvants, the insecticides aldicarb and acephate, and the adjuvant nonyl-phenoxy-poly(ethylene oxy)ethanol among moderate and severe cases. Odds ratios ranged from 1.9 to 2.9. CONCLUSIONS: Most pesticides were not associated with elevated hypospadias risk. For the few that were associated, results should be interpreted with caution until replicated in other study populations. PMID:24167181

  11. Transport Magnetic Proximity Effects in Platinum

    NASA Astrophysics Data System (ADS)

    Huang, Ssu-Yen

    2013-03-01

    Platinum (Pt) metal, being non-magnetic and having a strong spin-orbit coupling interaction, has been central in detecting pure spin current and establishing most of the recent spin-based phenomena. Thus, it is important to ascertain the transport and magnetic characteristics of thin Pt films in contact with a ferromagnet. In this work, we use both electric and thermal means to conclusively show the transport magnetic proximity effects (MPE) of thin Pt film in contact with ferromagnetic insulator YIG. At thicknesses comparable to, and less than, the spin diffusion length, the strong ferromagnetic characteristics in Pt films on YIG are indistinguishable from those of ferromagnetic permalloy on YIG. The MPE occurs at the interface and decreases exponentially away from the interface, concentrating in only a few monolayers. As a result, the pure spin current detected by a thin Pt is tainted with a spin polarized current. The pure spin current phenomena, such as the inverse spin Hall effect and the spin Seebeck effect, have been contaminated with the anomalous Hall effect and the anomalous Nernst effect respectively. These results raise serious questions about the suitability, and the validity, of using Pt in establishing pure spin current phenomena; on the other hand, a much stronger spin-based effect can be induced by the MPE at the interface. This research is in collaboration with X. Fin, Y. P. Chen, J. Wu, and J. Q. Xiao (University of Delaware), T. Y. Chen (Arizona State University) and D. Qu, W. G. Wang, and C. L. Chien (The Johns Hopkins University).

  12. Interactive orbital proximity operations planning system

    NASA Technical Reports Server (NTRS)

    Grunwald, Arthur J.; Ellis, Stephen R.

    1990-01-01

    An interactive graphical planning system for on-site planning of proximity operations in the congested multispacecraft environment about the space station is presented. The system shows the astronaut a bird's eye perspective of the space station, the orbital plane, and the co-orbiting spacecraft. The system operates in two operational modes: (1) a viewpoint mode, in which the astronaut is able to move the viewpoint around in the orbital plane to range in on areas of interest; and (2) a trajectory design mode, in which the trajectory is planned. Trajectory design involves the composition of a set of waypoints which result in a fuel-optimal trajectory which satisfies all operational constraints, such as departure and arrival constraints, plume impingement constraints, and structural constraints. The main purpose of the system is to present the trajectory and the constraints in an easily interpretable graphical format. Through a graphical interactive process, the trajectory waypoints are edited until all operational constraints are satisfied. A series of experiments was conducted to evaluate the system. Eight airline pilots with no prior background in orbital mechanics participated in the experiments. Subject training included a stand-alone training session of about 6 hours duration, in which the subjects became familiar with orbital mechanics concepts and performed a series of exercises to familiarize themselves with the control and display features of the system. They then carried out a series of production runs in which 90 different trajectory design situations were randomly addressed. The purpose of these experiments was to investigate how the planning time, planning efforts, and fuel expenditures were affected by the planning difficulty. Some results of these experiments are presented.

  13. A 17 year old with isolated proximal tibiofibular joint arthritis

    PubMed Central

    2013-01-01

    The proximal tibiofibular joint (TFJ) is rarely affected in rheumatic diseases, and we frequently interpret pain of the lateral knee as the result of overuse or trauma. Nonetheless, the TFJ is a synovial joint that communicates with the tibiofemoral joint in a proportion of patients. While proximal TFJ arthritis has been rarely associated with existing spondyloarthritis, isolated TFJ arthritis as the presenting manifestation of spondyloarthritis has not yet been described. Here, we report the clinical and radiographic presentation of an adolescent with chronic proximal TFJ arthritis heralding spondyloarthritis highly suggestive of ankylosing spondylitis. PMID:23302539

  14. Na+-sulfate cotransporter SLC13A1.

    PubMed

    Markovich, Daniel

    2014-01-01

    Sulfate is essential for normal physiology. The kidney plays a major role in sulfate homeostasis. Sulfate is freely filtered and strongly reabsorbed in the proximal tubule. The apical membrane Na(+)-sulfate cotransporter NaS1 (SLC13A1) mediates sulfate (re)absorption across renal proximal tubule and small intestinal epithelia. NaS1 encodes a 595-amino acid (? 66 kDa) protein with 13 putative transmembrane domains. Its substrate preferences are sodium and sulfate, thiosulfate, and selenate, and its activity is inhibited by molybdate, selenate, tungstate, thiosulfate, succinate, and citrate. NaS1 is primarily expressed in the kidney (proximal tubule) and intestine (duodenum to colon). NaS1 expression is down-regulated in the renal cortex by high sulfate diet, hypothyroidism, vitamin D depletion, glucocorticoids, hypokalemia, metabolic acidosis, and NSAIDs and up-regulated by low sulfate diet, thyroid hormone, vitamin D supplementation, growth hormone, chronic renal failure, and during post-natal growth. Disruption of murine NaS1 gene leads to hyposulfatemia and hypersulfaturia, as well as changes in metabolism, growth, fecundity, behavior, gut physiology, and liver detoxification. This suggests that NaS1 is an important sulfate transporter and its disruption leads to perturbed sulfate homeostasis, which contributes to numerous pathophysiological conditions. PMID:24193406

  15. Radiation interchange modeling for active infrared proximity sensor design

    E-print Network

    Piper, James Clarice

    1999-01-01

    . This research focuses on information gathered using active optical proximity sensors in the reflectance sensing mode. The portion of energy reflected to a given sensor in combination with the known location of the source and sensor elements provide the basic...

  16. Implementing Feedback Control on a Novel Proximity Operations Simulation Platform 

    E-print Network

    Aures-Cavalieri, Kurt Dale

    2012-07-16

    Recently, The Land, Air and Space Robotics (LASR) Laboratory has demonstrated a state-of-the-art proximity operations test bed that will revolutionize the concept of portable space systems simulation. The Holonomic Omni-directional Motion Emulation...

  17. Proximal bundle methods in depth: a unified analysis for inexact ...

    E-print Network

    2013-11-29

    (will be inserted by the editor). Proximal ... calities. Besides, several variants exist to deal with noise, each one needing an ad hoc proof .... in stochastic optimization, for problems with decision variables organized in two levels, denoted by u ...

  18. The development of an index for the proximal upper extremity 

    E-print Network

    Walline, Erin Kurusz

    2006-08-16

    Analysis techniques specific to the proximal upper extremity have historically been overlooked in the field of ergonomics. This research effort provides a methodology that will allow the ergonomics practitioner to analyze ...

  19. Deleting the TGF-? Receptor Attenuates Acute Proximal Tubule Injury

    PubMed Central

    Vadivelu, Sangeetha; Neelisetty, Surekha; Srichai, Manakan B.; Paueksakon, Paisit; Pozzi, Ambra; Harris, Raymond C.

    2012-01-01

    TGF-? is a profibrotic growth factor in CKD, but its role in modulating the kidney’s response to AKI is not well understood. The proximal tubule epithelial cell, which is the main cellular target of AKI, expresses high levels of both TGF-? and its receptors. To determine how TGF-? signaling in this tubular segment affects the response to AKI, we selectively deleted the TGF-? type II receptor in the proximal tubules of mice. This deletion attenuated renal impairment and reduced tubular apoptosis in mercuric chloride–induced injury. In vitro, deficiency of the TGF-? type II receptor protected proximal tubule epithelial cells from hydrogen peroxide–induced apoptosis, which was mediated in part by Smad-dependent signaling. Taken together, these results suggest that TGF-? signaling in the proximal tubule has a detrimental effect on the response to AKI as a result of its proapoptotic effects. PMID:23160515

  20. Planning and scheduling proximity operations for autonomous orbital rendezvous

    E-print Network

    Guerra, Christopher J., 1978-

    2003-01-01

    This thesis develops a mixed integer programming formulation to solve the proximity operations scheduling problem for autonomous orbital rendezvous. The algorithm of this thesis allows the operator to specify planned modes, ...

  1. Interracial Ratios and Proximity in Dormitories: Attitudes of University Students

    ERIC Educational Resources Information Center

    Bennett, Don C.

    1974-01-01

    A survey technique was used to investigate black and white undergraduate students' attitudes toward the minimum number of one's own race needed for comfort in dormitory residency and the relationship of proximity of one's race toward this number. (MLB)

  2. Interaction of cylinders In proximity under flow-induced vibration

    E-print Network

    Thekkoodan, Dilip Joy

    2014-01-01

    This study examines the influence of a stationary cylinder that is placed in proximity to a flexibly mounted cylinder in the side-by-side arrangement. The problem is investigated with an immersed-boundary formulation of a ...

  3. Challenger's RMS arm grasps SPAS-01 during proximity operations

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Challenger's remote manipulator system (RMS) arm grasps Shuttle pallet satellite (SPAS-01) during proximity operations. The frame shows a number of reflections on the window, located overhead in the aft flight deck.

  4. Technical tips: dualplate fixation technique for comminuted proximal humerus fractures.

    PubMed

    Choi, Sungwook; Kang, Hyunseong; Bang, Hyeongsig

    2014-08-01

    The authors report dualplate fixation technique for providing stable fixation in comminuted proximal humerus fractures. This technique has been used for proximal humerus fractures with metaphyseal comminution and provides excellent anatomical reduction and neck shaft angle (NSA). The recently locking plate is clinically more widely used due to its small size, low rigidity, high elasticity, and biomechanical properties such as fixed initial angle and rotational stability. However, in severely comminuted complex type proximal metaphyseal humerus fractures, the use of locking plate alone does not provide stable fixation, leading to complications such as varus collapse, anterior-posterior angulation, screw cutout, nonunion, malunion, and metal failure. Therefore, a more robust and enhanced fixation method, the dual plating technique using the locking compression plate (Proximal Humeral Internal Locking System and Variable Angle Locking Compression Plate) was developed. PMID:24813097

  5. View to northeast, showing west elevation and south side. Proximity ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View to northeast, showing west elevation and south side. Proximity of fence of adjacent subdivision precluded photography of north side. - Drew-Sherwood Farm, Barn, 7927 Elk Grove Boulevard, Elk Grove, Sacramento County, CA

  6. 7. Underside of deck and substructure, showing proximity of main ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Underside of deck and substructure, showing proximity of main street bridge from between both bridge, looking east - Claremont Railway Bridge, Spanning Sugar River at Claremont Railroad Company Line, Claremont, Sullivan County, NH

  7. Aorfix stent graft for abdominal aortic aneurysms reduces the risk of proximal type 1 endoleak in angulated necks: bench-test study.

    PubMed

    Albertini, Jean-Noël; DeMasi, Maria-Angela; Macierewicz, Jan; El Idrissi, Redouane; Hopkinson, Brian R; Clément, Claude; Branchereau, Alain

    2005-01-01

    Neck angulation (NA) is an important risk factor for type 1 proximal endoleaks following stenting of abdominal aortic aneurysms. The Aorfix (Lombard Medical, Oxon, UK) is a new flexible stent graft designed to overcome this issue. The aim of this study was to compare the endoleak flow rate (EFR) in relation to NA between the Aorfix and other manufactured stent grafts. A flow model with silicone proximal and distal necks was used. EFRs corresponding to 10 neck angles between 0 and 70 degrees were measured. Eight stent grafts were tested: Aorfix, Ancure (Guidant, Indianapolis, IN), Powerlink (Endologix, Irvine, CA), AneuRx (Medtronic, Sunnyvale, CA), Excluder (W.L. Gore & Associates, Flagstaff, AZ), Zenith and Zenith-Flex (Cook Inc., Bloomington, IN), and Lifepath (Edwards Lifesciences, Irvine, CA). For all stent grafts except the Aorfix, the EFR was greater than at baseline for NA >or= 30 degrees (p < .01). The EFR at NA >or= 30 degrees was lower with the Aorfix compared with the other stent grafts (p < .01). NA had no influence on the EFR with the Aorfix. The Aorfix may decrease the incidence of proximal type 1 endoleak in patients with a severely angulated aortic neck. PMID:16390649

  8. Silicon tunnel diodes formed by proximity rapid thermal diffusion

    Microsoft Academic Search

    Jinli Wang; Dane Wheeler; Yan Yan; Jialin Zhao; Scott Howard; Alan Seabaugh

    2003-01-01

    We demonstrate the first silicon tunnel diodes (TDs) formed using proximity rapid thermal diffusion and spin-on diffusants. Room temperature peak-to-valley current ratio of 2 is obtained at approximately 100 A\\/cm2 peak current density. Secondary ion mass spectroscopy is used to compare proximity rapid thermal diffusion with rapid thermal diffusion from spin-coated diffusants in direct contact with a device wafer. The

  9. Digital Image Enhancement Improves Diagnosis of Nondisplaced Proximal Femur Fractures

    Microsoft Academic Search

    Itamar Busheri Botser; Amir Herman; Ram Nathaniel; Dan Rappaport; Aharon Chechik

    2009-01-01

    Today most emergency room radiographs are computerized, making digital image enhancement a natural advancement to improve\\u000a fracture diagnosis. We compared the diagnosis of nondisplaced proximal femur fractures using four different image enhancement\\u000a methods using standard DICOM (Digital Imaging and Communications in Medicine) after window-leveling optimization. Twenty-nine\\u000a orthopaedic residents and specialists reviewed 28 pelvic images consisting of 25 occult proximal femur

  10. Voltage collapse proximity index determination using voltage phasors approach

    SciTech Connect

    Gubina, F.; Strmcnik, B. [Univ. of Ljubljana (Slovenia)] [Univ. of Ljubljana (Slovenia)

    1995-05-01

    In the paper, a phasor concept of voltage collapse proximity determination is presented. An adequate voltage proximity index is calculated based on the voltage phasor values only. Furthermore, an algorithm is derived which automatically detects the network transmission paths to the load nodes which are prone to voltage collapse due to additional real or reactive loading. The algorithm is tested on practical networks and exhibits comparable accuracy to the existing methods and low computing time consumption.

  11. Autosomal recessive renal proximal tubulopathy and hypercalciuria: a new syndrome

    Microsoft Academic Search

    Daniella Magen; Lior Adler; Hana Mandel; Edna Efrati; Israel Zelikovic

    2004-01-01

    Background: The best described primary inherited proximal tubulopathies include X-linked hypercalciuric nephrolithiasis (XLHN), caused by a mutation in the chloride channel gene CLCN5, and classic Fanconi’s syndrome, the genetic basis of which is unknown. The aim of this study is to examine the clinical, biochemical, and genetic characteristics of a highly consanguineous Druze family with autosomal recessive proximal tubulopathy and

  12. Private and Flexible Proximity Detection in Mobile Social Networks

    Microsoft Academic Search

    Laurynas Siksnys; Jeppe Rishede Thomsen; Simonas Saltenis; Man Lung Yiu

    2010-01-01

    A privacy-aware proximity detection service determines if two mobile users are close to each other without requiring them to disclose their exact locations. Existing proposals for such services provide weak privacy, give low accuracy guarantees, incur high communication costs, or lack flexibility in user preferences. We address these shortcomings with a client-server solution for proximity detection, based on encrypted, multi-level

  13. Nephrocalcinosis in glucose-galactose malabsorption: nephrocalcinosis and proximal tubular dysfunction in a young infant with a novel mutation of SGLT1.

    PubMed

    Soylu, Ozlem Bekem; Ecevit, Ci?dem; Altinöz, Serdar; Oztürk, Aysel Aydo?an; Temizkan, Ali Kemal; Maeda, Mari; Kasahara, Michihiro

    2008-12-01

    We report an association of proximal renal tubular dysfunction in a 50-day-old girl with glucose-galactose malabsorption who was found to have nephrocalcinosis, but no sign of nephrolithiasis. A novel homozygous nonsense mutation at 267Arg-->stop (CGA-->TGA) in the Na(+)-dependent glucose transporter (SGLT1) was found in loop 5 connecting transmembrane segments 6 and 7, indicating the complete loss of glucose transport activity. This case indicates that hypercalcaemia, nephrocalcinosis and proximal tubular dysfunction may be seen in association with glucose-galactose malabsorption and that most of these abnormalities improve with a glucose-galactose-free diet. PMID:18288487

  14. Developmental Changes in Proximal Tubule Tight Junction Proteins

    PubMed Central

    HADDAD, MAHA; LIN, FANGMING; DWARAKANATH, VANGIPURAM; CORDES, KIMBERLY; BAUM, MICHEL

    2014-01-01

    We demonstrated previously that neonatal proximal tubules have a lower passive paracellular permeability to chloride ions and higher resistance than that of adult proximal tubules. In addition, administration of thyroid hormone to neonates, before the normal maturational increase in serum thyroid hormone levels, prematurely accelerates the developmental increase in chloride permeability to adult levels. To test the hypothesis that there is a maturational change in tight junction proteins and that thyroid hormone mediates these changes, we examined the two known tight junction proteins present in proximal tubules, occludin and claudin 2. Using immunoblot and immunohistochemistry, we demonstrated that claudin 2 has a 4-fold greater abundance in neonatal proximal tubules than in adult tubules. Occludin, however, has a 4-fold greater expression in adult tubules than in neonatal tubules. Administration of thyroid hormone to neonates did not affect claudin 2 expression, occludin expression, or the transepithelial resistance in rat proximal tubule cells in vitro. In conclusion, there are postnatal maturational changes in tight junction proteins. The factors that cause these maturational changes are unknown but unlikely to be due solely to the maturational increase in thyroid hormone. PMID:15585672

  15. Ejecta emplacement: from distal to proximal

    NASA Astrophysics Data System (ADS)

    Artemieva, N.

    2008-09-01

    Introduction Most part of impact ejecta is deposited ballistically at some distance from a crater, defined by ejection velocity V and ejection angle ?: d=v2sin?/g. In case of giant impacts, planetary curvature should be taken into account [1]. Combined with ejecta scaling [2], these relations allow to define ejecta thickness as a function of distance. Ejecta from large craters are deposited at velocity high enough to mobilize substrate material and to thicken ejecta deposits [3]. Ballistic approximation is valid for airless bodies (if impact vaporization is not vast) or for proximal ejecta of large impact craters, where ejecta mass per unit area is substantially greater than the mass of involved vapor/atmosphere (M-ratio). Deposition of distal ejecta, in which ejecta mass is negligible compared to the atmosphere, may be also treated in a simplified manner, i.e. as 1) passive motion of ejected particles within an impact plume and 2) later, as sedimentation of particles in undisturbed atmosphere (equilibrium between gravity and drag). In all intermediate M-ratio values, impact ejecta move like a surge, i.e. dilute suspension current in which particles are carried in turbulent flows under the influence of gravity. Surges are well-known for near-surface explosive tests, described in detail for volcanic explosions (Plinian column collapse, phreato-magmatic eruption, lateral blast), and found in ejecta from the Chicxulub [4] and the Ries [5]. Important aspects of surge transport include its ability to deposit ejecta over a larger area than that typical of continuous ballistic ejecta and to create multiple ejecta layers. Numerical model Two-phase hydrodynamics. Surges should be modeled in the frame of two-phase hydrodynamics, i.e. interaction between solid/molten particles and atmospheric gas/impact vapor should be taken into account. There are two techniques of solving equations for dust particle motion in a gas flow. The first one describes solid/molten particles as a liquid with specific properties, i.e. finite-difference equations are the same as in standard hydrodynamics [6-8]. Another approach is based on solving equations of motion for representative particles [9]. Each of these markers describes the motion of a large number of real particles with similar sizes, velocities, and trajectories. Equation of motion (gravity, viscosity, and drag) is solved for every marker and then exchange of momentum, heat and energy with surrounding vaporair mixture is taken into account. This approach is used in the SOVA code [10] and allows to vary particle sizes within a broad range (from a few m to a few microns). Implicit procedure of velocity update allows a larger time step. The substantial advantage of the model is its three-dimensional geometry, allowing modeling of asymmetric deposits of oblique impact ejecta. Turbulent diffusion is taken into account in a simplified manner [6]. Fragments size-frequency distribution (SFD) may be of crucial importance: while large fragments move ballistically, the smallest ones are passively involved in gas motion. Ejected material is usually transformed into particles under tension. The initial particle velocity is given by the hydrodynamic velocity, but the object's initial position within the cell is randomly defined. The SFD of solid fragments in high velocity impacts has been studied experimentally [2,11], numerically [12,13], and has been derived from the lunar and terrestrial crater observations [14,15]. Various approaches may be used to implement fragment size in a dynamic model: in Grady-Kipp model the average fragment size is defined by strain rate [12]; alternatively, average ejection velocity [16] or maximum shock compression [17] may be used. All methods may be verified through comparison with known data. Volcanic direct blast. Numerical modeling of pyroclastic flows, checked against recent observations and young deposits, may be then a useful instrument for reconstruction of terrestrial craters' ejecta, which are mostly eroded or buried; and for impact ejecta study on other planets

  16. A biomechanical comparison of proximal femoral nails and locking proximal anatomic femoral plates in femoral fracture fixation

    PubMed Central

    Ozkan, Korhan; Türkmen, ?smail; Sahin, Adem; Yildiz, Yavuz; Erturk, Selim; Soylemez, Mehmet Salih

    2015-01-01

    Background: The incidence of fractures in the trochanteric area has risen with the increasing numbers of elderly people with osteoporosis. Although dynamic hip screw fixation is the gold standard for the treatment of stable intertrochanteric femur fractures, treatment of unstable intertrochanteric femur fractures still remains controversial. Intramedullary devices such as Gamma nail or proximal femoral nail and proximal anatomic femur plates are in use for the treatment of intertrochanteric femur fractures. There are still many investigations to find the optimal implant to treat these fractures with minimum complications. For this reason, we aimed to perform a biomechanical comparison of the proximal femoral nail and the locking proximal anatomic femoral plate in the treatment of unstable intertrochanteric fractures. Materials and Methods: Twenty synthetic, third generation human femur models, obtained for this purpose, were divided into two groups of 10 bones each. Femurs were provided as a standard representation of AO/Orthopedic Trauma Associationtype 31-A2 unstable fractures. Two types of implantations were inserted: the proximal femoral intramedullary nail in the first group and the locking anatomic femoral plate in the second group. Axial load was applied to the fracture models through the femoral head using a material testing machine, and the biomechanical properties of the implant types were compared. Result: Nail and plate models were locked distally at the same level. Axial steady load with a 5 mm/m velocity was applied through the mechanical axis of femur bone models. Axial loading in the proximal femoral intramedullary nail group was 1.78-fold greater compared to the plate group. All bones that had the plate applied were fractured in the portion containing the distal locking screw. Conclusion: The proximal femoral intramedullary nail provides more stability and allows for earlier weight bearing than the locking plate when used for the treatment of unstable intertrochanteric fractures of the femur. Clinicians should be cautious for early weight bearing with locking plate for unstable intertrochanteric femur fractures. PMID:26015637

  17. Proximity effect in a Nb-InAs-Nb nanowire junction

    NASA Astrophysics Data System (ADS)

    Baugh, Jonathan; Gharavi, Kaveh; Holloway, Greg; Haapamaki, Chris; Lapierre, Ray R.

    2014-03-01

    Proximity effect superconductivity in semiconductor-superconductor hybrid devices contains rich physics and could be key to the realization of topological quantum information processing. We have performed a series of low temperature electronic transport measurements on an InAs nanowire contacted with Niobium leads. The channel length (~ 4 times the nanowire diameter) is shorter than the electronic phase coherence length, but longer than the elastic mean free path, leading to behaviour that can be modelled by a superconductor-normal-superconductor junction in the diffusive transport regime. A supercurrent is observed below a critical current Ic of up to ~50 nA. The critical current varies with local gate voltages and correlates with the normal state conductance, producing modulation of Ic related to universal conductance fluctuations. An applied magnetic field produces a Gaussian decay of Ic, consistent with known theory. Analysis of multiple Andreev reflection corrections to conductance indicates a contact transparency ~0.6. The full results help to shed light on the nature of proximity effect superconductivity in a quasi-one-dimensional semiconductor in the quasi-diffusive regime. Supported by NSERC, Canada Foundation for Innovation.

  18. Proximity-dependent initiation of hybridization chain reaction

    PubMed Central

    Koos, Björn; Cane, Gaëlle; Grannas, Karin; Löf, Liza; Arngården, Linda; Heldin, Johan; Clausson, Carl-Magnus; Klaesson, Axel; Hirvonen, M. Karoliina; de Oliveira, Felipe M. S.; Talibov, Vladimir O.; Pham, Nhan T.; Auer, Manfred; Danielson, U. Helena; Haybaeck, Johannes; Kamali-Moghaddam, Masood; Söderberg, Ola

    2015-01-01

    Sensitive detection of protein interactions and post-translational modifications of native proteins is a challenge for research and diagnostic purposes. A method for this, which could be used in point-of-care devices and high-throughput screening, should be reliable, cost effective and robust. To achieve this, here we design a method (proxHCR) that combines the need for proximal binding with hybridization chain reaction (HCR) for signal amplification. When two oligonucleotide hairpins conjugated to antibodies bind in close proximity, they can be activated to reveal an initiator sequence. This starts a chain reaction of hybridization events between a pair of fluorophore-labelled oligonucleotide hairpins, generating a fluorescent product. In conclusion, we show the applicability of the proxHCR method for the detection of protein interactions and posttranslational modifications in microscopy and flow cytometry. As no enzymes are needed, proxHCR may be an inexpensive and robust alternative to proximity ligation assays. PMID:26065580

  19. Chiral spin torque arising from proximity-induced magnetization

    NASA Astrophysics Data System (ADS)

    Ryu, Kwang-Su; Yang, See-Hun; Thomas, Luc; Parkin, Stuart S. P.

    2014-05-01

    Domain walls can be driven by current at very high speeds in nanowires formed from ultra-thin, perpendicularly magnetized cobalt layers and cobalt/nickel multilayers deposited on platinum underlayers due to a chiral spin torque. An important feature of this torque is a magnetic chiral exchange field that each domain wall senses and that can be measured by the applied magnetic field amplitude along the nanowire where the domain walls stop moving irrespective of the magnitude of the current. Here we show that this torque is manifested when the magnetic layer is interfaced with metals that display a large proximity-induced magnetization, including iridium, palladium and platinum but not gold. A correlation between the strength of the chiral spin torque and the proximity-induced magnetic moment is demonstrated by interface engineering using atomically thin dusting layers. High domain velocities are found where there are large proximity-induced magnetizations in the interfaced metal layers.

  20. Comparison of different proximity potentials for asymmetric colliding nuclei

    SciTech Connect

    Dutt, Ishwar; Puri, Rajeev K. [Department of Physics, Panjab University, Chandigarh 160014 (India)

    2010-06-15

    Using the different versions of phenomenological proximity potential as well as other parametrizations within the proximity concept, we perform a detailed comparative study of fusion barriers for asymmetric colliding nuclei with asymmetry parameter as high as 0.23. In all, 12 different proximity potentials are robust against the experimental data of 60 reactions. Our detailed study reveals that the surface energy coefficient as well as radius of the colliding nuclei depend significantly on the asymmetry parameter. All models are able to explain the fusion barrier heights within +-10% on the average. The potentials due to Bass 80, AW 95, and Denisov DP explain nicely the fusion cross sections at above- as well as below-barrier energies.

  1. Ultrasound in Dual Nerve Impairment after Proximal Radial Nerve Lesion

    PubMed Central

    Lämmer, Alexandra B; Schwab, Stefan; Schramm, Axel

    2015-01-01

    Introduction Sonography in classical nerve entrapment syndromes is an established and validated method. In contrast, few publications highlight lesions of the radial nerve, particularly of the posterior interosseus nerve (PIN). Method Five patients with a radial nerve lesion were investigated by electromyography, nerve conduction velocity and ultrasound. Further normative values of 26 healthy subjects were evaluated. Results Four patients presented a clinical and electrophysiological proximal axonal radial nerve lesion and one patient showed a typical posterior interosseous nerve syndrome (PINS). The patient with PINS presented an enlargement of the PIN anterior to the supinator muscle. However four patients with proximal lesions showed an unexpected significant enlargement of the PIN within the supinator muscle. Conclusion High-resolution sonography is a feasible method to demonstrate the radial nerve including its distal branches. At least in axonal radial nerve lesions, sonography might reveal abnormalities far distant from a primary proximal lesion site clearly distinct from the appearance in classical PINS. PMID:25992766

  2. Proximity-dependent initiation of hybridization chain reaction.

    PubMed

    Koos, Björn; Cane, Gaëlle; Grannas, Karin; Löf, Liza; Arngården, Linda; Heldin, Johan; Clausson, Carl-Magnus; Klaesson, Axel; Hirvonen, M Karoliina; de Oliveira, Felipe M S; Talibov, Vladimir O; Pham, Nhan T; Auer, Manfred; Danielson, U Helena; Haybaeck, Johannes; Kamali-Moghaddam, Masood; Söderberg, Ola

    2015-01-01

    Sensitive detection of protein interactions and post-translational modifications of native proteins is a challenge for research and diagnostic purposes. A method for this, which could be used in point-of-care devices and high-throughput screening, should be reliable, cost effective and robust. To achieve this, here we design a method (proxHCR) that combines the need for proximal binding with hybridization chain reaction (HCR) for signal amplification. When two oligonucleotide hairpins conjugated to antibodies bind in close proximity, they can be activated to reveal an initiator sequence. This starts a chain reaction of hybridization events between a pair of fluorophore-labelled oligonucleotide hairpins, generating a fluorescent product. In conclusion, we show the applicability of the proxHCR method for the detection of protein interactions and posttranslational modifications in microscopy and flow cytometry. As no enzymes are needed, proxHCR may be an inexpensive and robust alternative to proximity ligation assays. PMID:26065580

  3. [Determination of proximal chemical composition of squid (dosidicus gigas) and development of gel products].

    PubMed

    Abugoch, L; Guarda, A; Pérez, L M; Paredes, M P

    1999-06-01

    The good nutritional properties of meat from big squid (Dosidicus gigas) living on the Chilean coast, was determined through its proximal composition 70 cal/100 g fresh meat; 82.23 +/- 0.98% moisture; 15.32 +/- 0.93% protein; 1.31 +/- 0.12% ashes; 0.87 +/- 0.18% fat and 0.27% NNE (non-nitrogen extract). The big squid meat was used to develop a gel product which contained NaCl and TPP. It was necessary to use additives for gel preparation, such as carragenin or alginate or egg albumin, due to the lack of gelation properties of squid meat. Formulations containing egg albumin showed the highest gel force measured by penetration as compared to those that contained carragenin or alginate. PMID:10488395

  4. Endogenous production of angiotensin II modulates rat proximal tubule transport.

    PubMed Central

    Quan, A; Baum, M

    1996-01-01

    There is evidence that angiotensin II is synthesized by the proximal tubule and secreted into the tubular lumen. This study examined the functional significance of endogenously produced angiotensin II on proximal tubule transport in male Sprague-Dawley rats. Addition of 10(-11), 10(-8), and 10(-6) M angiotensin II to the lumen of proximal convoluted tubules perfused in vivo had no effect on the rate of fluid reabsorption. The absence of an effect of exogenous luminal angiotensin II could be due to its endogenous production and luminal secretion. Luminal 10(-8) M Dup 753 (an angiotensin II receptor antagonist) resulted in a 35% decrease in proximal tubule fluid reabsorption when compared to control (Jv = 1.64 +/- 0.12 nl/mm.min vs. 2.55 +/- 0.32 nl/mm.min, P < 0.05). Similarly, luminal 10(-4) M enalaprilat, an angiotensin converting enzyme inhibitor, decreased fluid reabsorption by 40% (Jv = 1.53 +/- 0.23 nl/mm.min vs. 2.55 +/- 0.32 nl/mm.min, P < 0.05). When 10(-11) or 10(-8) M exogenous angiotensin II was added to enalaprilat (10(-4) M) in the luminal perfusate, fluid reabsorption returned to its baseline rate (Jv = 2.78 +/- 0.35 nl/mm.min). Thus, addition of exogenous angiotensin II stimulates proximal tubule transport when endogenous production is inhibited. These experiments show that endogenously produced angiotensin II modulates fluid transport in the proximal tubule independent of systemic angiotensin II. PMID:8675701

  5. An experiment in manipulator control with proximity sensors

    NASA Technical Reports Server (NTRS)

    Johnston, A. R.

    1974-01-01

    Optical proximity sensors were used in a feedback loop to automatically position a manipulator hand for grasping. The experiment was a simplified one, involving two dimensional motion only. Two proximity sensors were mounted on the hand, and control signals derived from their outputs were used to drive the hand vertically and horizontally. The sensors employ a pulsed gallium arsenide light-emitting diode together with a silicon detector. They indicate, without contact, the approximate distance between the manipulator hand and object in the range from 5 to 12 cm. Positioning within approximately + or - 5 mm was observed. Extension of the technique to general three-dimensional control is briefly discussed.

  6. Investigation of proximity effects in electron microscopy and lithography

    SciTech Connect

    Walz, M.-M.; Vollnhals, F.; Rietzler, F.; Schirmer, M.; Steinrueck, H.-P.; Marbach, H.

    2012-01-30

    A fundamental challenge in lithographic and microscopic techniques employing focused electron beams are so-called proximity effects due to unintended electron emission and scattering in the sample. Herein, we apply a method that allows for visualizing electron induced surface modifications on a SiN substrate covered with a thin native oxide layer by means of iron deposits. Conventional wisdom holds that by using thin membranes proximity effects can be effectively reduced. We demonstrate that, contrary to the expectation, these can be indeed larger on a 200 nm SiN-membrane than on the respective bulk substrate due to charging effects.

  7. Lateral Casimir Force beyond the Proximity-Force Approximation

    SciTech Connect

    Rodrigues, Robson B.; Neto, Paulo A. Maia [Instituto de Fisica, UFRJ, CP 68528, Rio de Janeiro, RJ, 21941-972 (Brazil); Lambrecht, Astrid; Reynaud, Serge [Laboratoire Kastler Brossel, CNRS, ENS, Universite Pierre et Marie Curie case 74, Campus Jussieu, F-75252 Paris Cedex 05 (France)

    2006-03-17

    We argue that the appropriate variable to study a nontrivial geometry dependence of the Casimir force is the lateral component of the Casimir force, which we evaluate between two corrugated metallic plates outside the validity of the proximity-force approximation. The metallic plates are described by the plasma model, with arbitrary values for the plasma wavelength, the plate separation, and the corrugation period, the corrugation amplitude remaining the smallest length scale. Our analysis shows that in realistic experimental situations the proximity-force approximation overestimates the force by up to 30%.

  8. Dacron collateral ligament reconstruction with proximal interphalangeal joint arthroplasty.

    PubMed

    Hunter, J M; Sattel, A; Kirkpatrick, W H

    1991-04-01

    A porous Dacron (Phoenix Bioengineering, Bridgeport, PA) tendon is described for collateral ligament reconstruction and augumentation with proximal interphalangeal joint implant arthroplasty. Eight cases with a minimum follow-up of 15 months are reviewed. Diagnoses include posttraumatic arthritis and osteoarthritis, as well as rheumatoid arthritis. The porous Dacron tendon is constructed as a collagen-like weave. It has been useful in patients who have insufficient local tissue to achieve lateral proximal interphalangeal joint stability. In selected cases, it can obviate the need for a tendon graft and provide an alternative to arthrodesis. PMID:10171175

  9. Inverse Proximity Effect in Superconductor-ferromagnet Bilayer Structures

    SciTech Connect

    Xia, Jing

    2010-04-05

    Measurements of the polar Kerr effect using a zero-area-loop Sagnac magnetometer on Pb/Ni and Al/(Co-Pd) proximity-effect bilayers show unambiguous evidence for the 'inverse proximity effect,' in which the ferromagnet (F) induces a finite magnetization in the superconducting (S) layer. To avoid probing the magnetic effects in the ferromagnet, the superconducting layer was prepared much thicker than the light's optical penetration depth. The sign and size of the effect, as well as its temperature dependence agree with recent predictions by Bergeret et al.[1].

  10. Proximity Operations Nano-Satellite Flight Demonstration (PONSFD) Rendezvous Proximity Operations Design and Trade Studies

    NASA Astrophysics Data System (ADS)

    Griesbach, J.; Westphal, J. J.; Roscoe, C.; Hawes, D. R.; Carrico, J. P.

    2013-09-01

    The Proximity Operations Nano-Satellite Flight Demonstration (PONSFD) program is to demonstrate rendezvous proximity operations (RPO), formation flying, and docking with a pair of 3U CubeSats. The program is sponsored by NASA Ames via the Office of the Chief Technologist (OCT) in support of its Small Spacecraft Technology Program (SSTP). The goal of the mission is to demonstrate complex RPO and docking operations with a pair of low-cost 3U CubeSat satellites using passive navigation sensors. The program encompasses the entire system evolution including system design, acquisition, satellite construction, launch, mission operations, and final disposal. The satellite is scheduled for launch in Fall 2015 with a 1-year mission lifetime. This paper provides a brief mission overview but will then focus on the current design and driving trade study results for the RPO mission specific processor and relevant ground software. The current design involves multiple on-board processors, each specifically tasked with providing mission critical capabilities. These capabilities range from attitude determination and control to image processing. The RPO system processor is responsible for absolute and relative navigation, maneuver planning, attitude commanding, and abort monitoring for mission safety. A low power processor running a Linux operating system has been selected for implementation. Navigation is one of the RPO processor's key tasks. This entails processing data obtained from the on-board GPS unit as well as the on-board imaging sensors. To do this, Kalman filters will be hosted on the processor to ingest and process measurements for maintenance of position and velocity estimates with associated uncertainties. While each satellite carries a GPS unit, it will be used sparsely to conserve power. As such, absolute navigation will mainly consist of propagating past known states, and relative navigation will be considered to be of greater importance. For relative observations, each spacecraft hosts 3 electro-optical sensors dedicated to imaging the companion satellite. The image processor will analyze the images to obtain estimates for range, bearing, and pose, with associated rates and uncertainties. These observations will be fed to the RPO processor's relative Kalman filter to perform relative navigation updates. This paper includes estimates for expected navigation accuracies for both absolute and relative position and velocity. Another key task for the RPO processor is maneuver planning. This includes automation to plan maneuvers to achieve a desired formation configuration or trajectory (including docking), as well as automation to safely react to potentially dangerous situations. This will allow each spacecraft to autonomously plan fuel-efficient maneuvers to achieve a desired trajectory as well as compute adjustment maneuvers to correct for thrusting errors. This paper discusses results from a trade study that has been conducted to examine maneuver targeting algorithms required on-board the spacecraft. Ground software will also work in conjunction with the on-board software to validate and approve maneuvers as necessary.

  11. Autonomous Distributed Control of Simultaneous Multiple Spacecraft Proximity Maneuvers

    Microsoft Academic Search

    Shawn Baxter McCamish; Marcello Romano; Xiaoping Yun

    2010-01-01

    An autonomous distributed control algorithm for multiple spacecraft performing simultaneous close proximity maneuvers has been developed. Examples of these maneuvers include automated on-orbit inspection, assembly, or servicing. The proposed control algorithm combines the control effort efficiency of the Linear Quadratic Regulator (LQR) and the robust collision avoidance capability of the Artificial Potential Function (APF) method. The LQR control effort serves

  12. DISPATCHING OF COORDINATED PROXIMITY SENSORS FOR OBJECT SURVEILLANCE

    E-print Network

    Naish, Michael D.

    DISPATCHING OF COORDINATED PROXIMITY SENSORS FOR OBJECT SURVEILLANCE Michael D. Naish Elizabeth A demonstrate the advantages of dispatching dynamic sensors over similar static­sensor systems. INTRODUCTION This paper considers the principles of dispatching applied to the surveillance of a maneuvering object. Just

  13. PROXIMITY OF LOUISIANA SANITARY LANDFILLS TO WETLANDS AND DEEPWATER HABITATS

    EPA Science Inventory

    Sanitary landfills can cause considerable harm to sensitive ecosystems if they are not properly located, designed, and managed. The proximity of Louisiana sanitary landfills to wetlands and deepwater habitats was determined by drawing three concentric 1/4 mile, 1/2 mile, and 1 mi...

  14. Energy Efficient Transmission Scheduling over Mars Proximity Alessandro Tarello

    E-print Network

    Modiano, Eytan

    obtained from NASA's 2001 Mars Odyssey or- biter and the Mars Exploration Rover (MER) project, show overEnergy Efficient Transmission Scheduling over Mars Proximity Links Alessandro Tarello Electronics the scheduling of transmissions from an en- ergy limited Mars lander to a Mars orbiter. Typically, the channel

  15. On the Surprising Salience of Curvature in Grouping by Proximity

    ERIC Educational Resources Information Center

    Strother, Lars; Kubovy, Michael

    2006-01-01

    The authors conducted 3 experiments to explore the roles of curvature, density, and relative proximity in the perceptual organization of ambiguous dot patterns. To this end, they developed a new family of regular dot patterns that tend to be perceptually grouped into parallel contours, dot-sampled structured grids (DSGs). DSGs are similar to the…

  16. Small planar UWB antennas in proximity of human head

    Microsoft Academic Search

    Zhi Ning Chen; Ailian Cai; T. S. P. See; M. Y. W. Chia

    2005-01-01

    The effects of a human head on the performance of a small planar ultra-wideband (UWB) antenna in proximity of the head are investigated. A numerical head model developed by REMCOM is used in the XFDTD software package in the study, where the frequency-dependent dielectric constant and conductivity are obtained from the average data of anatomical human heads. A planar antenna

  17. Small planar UWB antennas in proximity of the human head

    Microsoft Academic Search

    Zhi Ning Chen; Ailian Cai; T. S. P. See; Xianming Qing; M. Y. W. Chia

    2006-01-01

    The effects of a human head on the performance of small planar ultra-wideband (UWB) antennas in proximity of the head are investigated numerically and experimentally. In simulation, a numerical head model is used in the XFDTD software package. The head model developed by REMCOM is with the frequency-dependent dielectric constant and conductivity obtained from the average data of anatomical human

  18. Proximal-ACCPM: a versatile oracle based optimization method

    E-print Network

    Beltran-Royo, Cesar

    Proximal-ACCPM: a versatile oracle based optimization method F. Babonneau C. Beltran A. Haurie C. Tadonki J.-P. Vial revised version, June 2005 Abstract Oracle Based Optimization (OBO) conveniently approximation revealed by an oracle. We show, through three representative examples, how difficult problems can

  19. Proximate and Distal Variables in the Demography of Rendille Pastoralists

    Microsoft Academic Search

    Eric Abella Roth

    1999-01-01

    Following the widespread application and success of Bongaarts' proximate fertility framework in the 1980s, anthropologists and demographers have shown increased interest in the delineation of distal fertility variables, alternatively called higher-order by cultural ecologists or ultimate variables by evolutionary ecologists. This shift in focus raises at least four immediate issues: (1) confusion over the role and effect of culture on

  20. An interior proximal point method with ?-divergence for Equilibrium ...

    E-print Network

    2013-05-07

    For solving this problem, we developed an interior proximal point algorithm ... Let E be a Euclidean space, whose inner product and norm are denoted by ?., .? and ., respectively. .... Proof See [2, Proposition 2.1] and [6, Lemma 2.1]. The main ...

  1. A Proximal Algorithm with Quasi Distance. Application to Habit's ...

    E-print Network

    2010-05-20

    The proximal algorithm has been first introduced by Martinet [17] and Rock- afellar [21] as an ... scheme (1.2) has been studied to change the Euclidean norm by an adequate like ..... Proof: From the axiom (2), for all x, y ? IRn we obtain. |q(

  2. Two-Sided Error Proximity Oblivious Testing Oded Goldreich

    E-print Network

    Goldreich, Oded

    .2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.3 POTs can test only intervalsTwo-Sided Error Proximity Oblivious Testing Oded Goldreich Igor Shinkar June 11, 2012 Abstract number of queries to a tested object and distinguishes objects that have a predetermined property from

  3. Two-Sided Error Proximity Oblivious Testing Oded Goldreich

    E-print Network

    Goldreich, Oded

    .2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.3 POTs can test only intervalsTwo-Sided Error Proximity Oblivious Testing Oded Goldreich Igor Shinkar January 26, 2014 Abstract number of queries to a tested object and distinguishes objects that have a predetermined property from

  4. Two-Sided Error Proximity Oblivious Testing Oded Goldreich

    E-print Network

    Goldreich, Oded

    .2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.3 POTs can test only intervalsTwo-Sided Error Proximity Oblivious Testing Oded Goldreich Igor Shinkar June 9, 2014 Abstract number of queries to a tested object and distinguishes objects that have a predetermined property from

  5. Two-Sided Error Proximity Oblivious Testing Oded Goldreich

    E-print Network

    Goldreich, Oded

    .2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.3 POTs can test only intervalsTwo-Sided Error Proximity Oblivious Testing Oded Goldreich Igor Shinkar April 2, 2012 Abstract number of queries to a tested object and distinguishes objects that have a predetermined property from

  6. Long-range singlet proximity effect in ferromagnetic nanowires

    NASA Astrophysics Data System (ADS)

    Konschelle, F.; Cayssol, J.; Buzdin, A.

    2010-11-01

    Recently a long-ranged superconductor/ferromagnet (S/F) proximity effect has been reported in Co crystalline nanowires [J. Wang, M. Singh, M. Tian, N. Kumar, B. Liu, C. Shi, J. K. Jain, N. Samarth, T. E. Mallouk, and M. H. W. Chan, Nat. Phys. 6, 389 (2010)10.1038/nphys1621]. Since the authors take care to avoid the existence of magnetic domains, the triplet character of the long-ranged proximity effect is improbable. Here we demonstrate that in the one-dimensional ballistic regime the standard singlet S/F proximity effect becomes long ranged. We provide an exact solution for the decay of the superconducting correlations near critical temperature (Tc) and for arbitrary impurities concentration. In particular, we find a specific regime, between the diffusive and ballistic ones, where the decay length is simply the electronic mean-free path. Finally possible experiments which could permit to elucidate the nature of the observed long-ranged proximity effect in Co nanowires are discussed.

  7. Proximate nutritive value changes during decomposition of salt marsh plants

    Microsoft Academic Search

    Armando A. Cruz

    1975-01-01

    Recognition of salt marsh plant detritus as a nutritious source of food for estuarine consumers prompted investigation of in situ decomposition and proximate nutritive values of three plants and their detritus namely: Spartina cynosuroides and Distichlis spicata (Gramineae) and Scirpus americanus (Cyperaceae) growing abundantly in Mississippi tidal marshes. During decomposition to particulate detritus, these plants retain 60–70% organic content and

  8. Quantum superconductor metal transition in a proximity array

    E-print Network

    Skvortsov, Mikhail

    Quantum superconductor ± metal transition in a proximity array M V Fe|¯gel'man, A I Larkin, M A Skvortsov Abstract. A theory of the zero-temperature superconductor- metal transition is developed [1] that the superconductor ± insulator transi- tion happens at the universal quantum value RQ ha4e2

  9. SENSITIVITY AND REGIONALLY PROXIMAL RELATION IN MINIMAL SYSTEMS

    E-print Network

    Shao, Song

    SENSITIVITY AND REGIONALLY PROXIMAL RELATION IN MINIMAL SYSTEMS SONG SHAO, XIANGDONG YE AND RUIFENG ZHANG Abstract. A topological dynamical system is n-sensitive, if there is a positive constant at least for a same moment. The properties of n-sensitivity in minimal systems are investigated. It turns

  10. ACCESSING LOCATION AND PROXIMITY INFORMATION IN A DECENTRALIZED ENVIRONMENT

    E-print Network

    Steimann, Friedrich

    ACCESSING LOCATION AND PROXIMITY INFORMATION IN A DECENTRALIZED ENVIRONMENT Location Resolution a mobile user's current location and provide location-depend- ent output. Often, such applications still into account the requirements of clients in mobile environments. Our algorithms are based on a decentralized

  11. CFN Operations and Safety Awareness (COSA) Checklist Proximal Probes Facility

    E-print Network

    Ohta, Shigemi

    Gas TQ-COMPGAS-1 X X X X Cryogen Safety HP-OSH-25 X X X X Electrical Safety for Benchtop Workers TQ: No work on exposed parts above 50V without Electrical Safety 1 Training and Dept. ES&H approval FurtherCFN Operations and Safety Awareness (COSA) Checklist Proximal Probes Facility Building 735

  12. Proximal versus Distal Validity Coefficients for Teacher Observational Instruments

    ERIC Educational Resources Information Center

    Marzano, Robert J.

    2014-01-01

    This study examined the use of measures of student learning computed using end-of-year assessments (distal measures) versus measures of student learning associated with a single lesson (proximal measures) as criterion scores for the validity of observations of teachers' pedagogical skills. The validity coefficients computed using distal…

  13. Proximity problems for time metrics induced metric and isothetic networks

    E-print Network

    Palop del Río, Belén

    velocity in the plane. Let v be the travelling speed on the network and v 0 the travelling speed on the plane for the L1 metric and we study several issues on proximity problems for this metric. Key words transportation network on the plane. Assume that any point on this network is an acces point to it. Furthermore

  14. Residential proximity to major roads and obstetrical complications.

    PubMed

    Yorifuji, Takashi; Naruse, Hiroo; Kashima, Saori; Murakoshi, Takeshi; Doi, Hiroyuki

    2015-03-01

    Exposure to air pollution is linked with an increased risk of preterm births. To provide further evidence on this relationship, we evaluated the association between proximity to major roads--as an index for air pollution exposure--and various obstetrical complications. Data were extracted from a database maintained by the perinatal hospital in Shizuoka, Japan. We restricted the analysis to mothers with singleton pregnancies of more than 22 weeks of gestation from 1997 to 2012 (n=19,077). Using the geocoded residential information, each mother was assigned proximity to major roads. We then estimated multivariate adjusted odds ratios and their 95% confidence intervals (CIs) for the effects of proximity to major roads on various obstetrical complications (preeclampsia, gestational diabetes mellitus, placenta abruption, placenta previa, preterm premature rupture of membrane (pPROM), preterm labor, and preterm births). We found positive associations of proximity to major roads with preeclampsia and pPROM. Living within 200 m increased the odds of preeclampsia by 1.3 times (95% CI, 1.0-1.8) and pPROM by 1.6 times (95% CI, 1.1-2.2). Furthermore, living within 200 m increased the odds of preterm births by 1.4 fold (95% CI, 1.2-1.7). Exposure to traffic-related air pollution increased the risk of preeclampsia and pPROM in this study. We propose a mechanism responsible for the association between air pollution and preterm births. PMID:25478655

  15. NOAA Technical Report NMFS 74 Proximate Composition and Fatty

    E-print Network

    NOAA Technical Report NMFS 74 Proximate Composition and Fatty Acid and Cholesterol Content of 22.S. Department of Commerce May 1989 #12;NOAA TECHNICAL REPORT NMFS _ The major responsibilities of the National. It collects, analyzes, and publishes statistics on various phases of the industry. The NOAA Technical Report

  16. Spaces of Innovation: Learning, Proximity and the Ecological Turn

    Microsoft Academic Search

    Adrian Healy; Kevin Morgan

    2012-01-01

    Healy A. and Morgan K. Spaces of innovation: learning, proximity and the ecological turn, Regional Studies. Contrary to the fashionable ‘death of distance’ thesis, the socio-spatial context for innovation remains as important as ever for firms, networks and the public institutions that tend to be neglected in orthodox narratives of learning. This article explores the changing socio-spatial dynamics of innovation

  17. Challenger's RMS arm grasps SPAS-01 during proximity operations

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Challenger's remote manipulator system (RMS) arm grasps Shuttle pallet satellite (SPAS-01) during proximity operations. Behind the SPAS-01 can be seen the clouded surface of the earth. The frame shows a number of reflections on the window, located overhead in the aft flight deck.

  18. The physiology of the female orgasm as a proximate mechanism

    Microsoft Academic Search

    Lara Eschler

    2004-01-01

    The dynamics of female orgasms were investigated and proposed as a possible proximate mechanism implicated in female mating strategies. Specifically, the role of female orgasm in motivating women to engage in sexual relations while refraining from engaging indiscriminately in one-night stands (ONS) was explored. A total of 202 Western women of reproductive age were surveyed about their sexual behaviour, practices,

  19. Trampoline Fracture of the Proximal Tibia in Children

    Microsoft Academic Search

    Richard S. Boyer; Richard B. Jaffe; George W. Nixon; Virgil R. Condon

    Seven children (aged 2-5 years) sustained fractures of the proximal tibial metaphysis while jumping on a trampoline with a heavier child or adult. Most impaction fractures were transverse and neither angulated nor displaced. None of the children developed permanent disability or impairment. Parents and physicians should be aware of the possible danger to small children while tandem jumping on a

  20. Efficient Private Techniques for Verifying Social Proximity Michael J. Freedman

    E-print Network

    Singh, Jaswinder Pal

    Efficient Private Techniques for Verifying Social Proximity Michael J. Freedman and Antonio privacy and security goals at a fraction of the cost of its current Private Matching [3] pro- tocol-fold. First, we describe and define a security model for verifying social con- nectedness in a privacy

  1. Connectivity of Cognitive Radio Networks: Proximity vs. Opportunity

    E-print Network

    Islam, M. Saif

    with different priorities such as cognitive radio (CR) networks. The problem is fundamentally dif- ferent fromConnectivity of Cognitive Radio Networks: Proximity vs. Opportunity Wei Ren and Qing Zhao Dept the connectivity of large-scale ad hoc cognitive radio networks, where secondary users exploit channels temporarily

  2. Arterial blood supply of the proximal humeral epiphysis

    Microsoft Academic Search

    F. Duparc; J.-M. Muller; P. Frçger

    2001-01-01

    The arterial blood supply of the proximal humeral epiphysis is known to derive mainly from the anterior humeral circumflex a. (ACA), but this description may minimize the role of the posterior circumflex humeral a. (PCA). The studies of Laing [9] and Gerber [3] emphasized the role of the ACA and of its branches, the ascending anterolateral artery and arcuate artery

  3. The proximity of hotspots to convergent and divergent plate boundaries

    Microsoft Academic Search

    Stuart A. Weinstein; Peter L. Olson

    1989-01-01

    An analysis of four different hotspot distributions, ranging from Morgan's (1972) original list of 19 to Vogt's (1981) list of 117 reveals that the hotspots are preferentially located near divergent plate boundaries. The probability of this proximity occurring by chance alone is quite remote, less than 0.01 for all four hotspots distributions. The same analysis also reveals that the hotspots

  4. The proximity of hotspots to convergent and divergent plate boundaries

    Microsoft Academic Search

    Stuart A. Weinstein; Peter L. Olson

    1989-01-01

    An analysis of four different hotspot distributions, ranging from Morgan's (1972) original list of 19 to Vogt's (1981) list of 117 reveals that the hotspots are preferentially located near divergent plate boundaries. The probability of this proximity occurring by chance alone is quite remote, less than 0.01 for all four hotspot distributions. The same analysis also reveals that the hotspots

  5. The proximity of hotspots to convergent and divergent plate boundaries

    Microsoft Academic Search

    Stuart A. Weinstein; Peter L. Olson

    1989-01-01

    An analysis of four different hotspot distributions, ranging from Morgan's [1972] original list of 19 to Vogt's [1981] list of 117 reveals that the hotspots are preferentially located near divergent plate boundaries. The probability of this proximity occurring by chance alone is quite remote, less than 0.01 for all four hotspot distributions. The same analysis also reveals that the hotspots

  6. Initial experience with proximal anastomoses performed with a mechanical connector

    Microsoft Academic Search

    Michael J Mack; Robert W Emery; Laura R Ley; Peter A Cole; Allie Leonard; James R Edgerton; Todd M Dewey; Mitchell J Magee; Thomas S Flavin

    2003-01-01

    BackgroundThe Symmetry Bypass System Aortic Connector (St Jude Medical, Inc) is a novel device for the construction of sutureless proximal anastomoses. The connector allows attachment of saphenous vein grafts to the aorta without requiring aortic clamping. We report our initial clinical experience with this device.

  7. The proximity of co-citation Shengbo Liu Chaomei Chen

    E-print Network

    Chen, Chaomei

    The proximity of co-citation Shengbo Liu · Chaomei Chen Received: 29 November 2011 / Published online: 20 December 2011 Ó Akade´miai Kiado´, Budapest, Hungary 2011 Abstract Traditional co-citation are cited by the same article, they are retreated equally regardless the distance between where citations

  8. Proximal Positioning: A Strategy of Practice in Violin Pedagogy.

    ERIC Educational Resources Information Center

    Gholson, Sylvia A.

    1998-01-01

    Attempts to identify and characterize patterns of expert teaching practice as they occur in context, and to confirm these patterns through processes of verification. Observes teacher Dorothy DeLay in her studio, documenting her teaching through notes, audiotapes, and contextual artifacts. Discusses DeLay's theory of proximal positioning in…

  9. West and south elevations, view to northeast. Proximity of house ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    West and south elevations, view to northeast. Proximity of house and trees precluded photography of north and east elevations, but building is symmetrical. Entry is in east elevation; windmill was mounted at third story level on north elevation. - Drew-Sherwood Farm, Tank House, 7927 Elk Grove Boulevard, Elk Grove, Sacramento County, CA

  10. Proximal dup(10q): Case report and literature review

    SciTech Connect

    Barritt, J.A.; Teague, K.E.; Bodurtha, J.N. [Virginia Commonwealth Univ., Richmond, VA (United States)] [and others

    1994-09-01

    We report a case of a proximal dir dup(10q) in a female with multiple congenital anomalies. During infancy she was noted to gave growth retardation, microcephaly, microphthalmia, coloboma, a long, beaked nose, posteriorly rotated ears with simple helices, full bowed lips, widely-spaced nipples, broad first toes, hypermobile and proximally placed thumbs, a heart murmur, PDA, and coarctation of the aorta. Additional findings at age 13 included a full columella, short philtrum, thin limbs, bilateral blindness, and mental retardation, as well as continued growth retardation. Her medical history included precocious puberty at age 8 and a diagnosis of hyperactivity. Using FISH with multiple probes combined with GTG-banding, the aberrant chromosome was determined to be a dir dup(10)(q21{r_arrow}q22). Parental chromosomes were normal and the family history was unremarkable. The parental origin of the dir dup(10) is being assessed using DNA markers. Five similar cases of proximal dup(10q) have been reported previously. Consistent characteristics include low birth weight, developmental and psychomotor delay, growth retardation, and microcephaly. Also found in most cases were short prominent philtrum, bowed mouth, PDA, thin limbs, coloboma, micropthalmia, deep set eyes, and other ocular anomalies. Our case is unique in that she has a long, beaked nose, precocious puberty, and hyperactivity. Future studies such as this, using molecular cytogenetic techniques to better define the chromatin involved in proximal dup(10q), may lead to its recognition as a distinct clinical phenotype.

  11. Proximity to Coast Is Linked to Climate Change Belief

    PubMed Central

    Milfont, Taciano L.; Evans, Laurel; Sibley, Chris G.; Ries, Jan; Cunningham, Andrew

    2014-01-01

    Psychologists have examined the many psychological barriers to both climate change belief and concern. One barrier is the belief that climate change is too uncertain, and likely to happen in distant places and times, to people unlike oneself. Related to this perceived psychological distance of climate change, studies have shown that direct experience of the effects of climate change increases climate change concern. The present study examined the relationship between physical proximity to the coastline and climate change belief, as proximity may be related to experiencing or anticipating the effects of climate change such as sea-level rise. We show, in a national probability sample of 5,815 New Zealanders, that people living in closer proximity to the shoreline expressed greater belief that climate change is real and greater support for government regulation of carbon emissions. This proximity effect held when adjusting for height above sea level and regional poverty. The model also included individual differences in respondents' sex, age, education, political orientation, and wealth. The results indicate that physical place plays a role in the psychological acceptance of climate change, perhaps because the effects of climate change become more concrete and local. PMID:25047568

  12. Proximity soundings of thundersnow in the central United States

    Microsoft Academic Search

    Angela M. Oravetz; David Gaede; Evan Bookbinder; Anthony R. Lupo; Christopher J. Melick; Larry L. Smith; Rashida Thomas; Rachel Redburn; Brian P. Pettegrew; Amy E. Becker

    2006-01-01

    Proximity balloon soundings for snow events with lightning and thunder during the period 1961 through 1990 reveal a less statically stable environment than similar nonthundering snow events. When thundersnow is present, a less stable environment (and in some cases subsequent upright convection) is found aloft in all of the thundering cases examined here; all of the events feature their most

  13. Capacitive Proximity Communication with Distributed Alignment Sensing for Origami

    E-print Network

    Emami-Neyestanak, Azita

    Capacitive Proximity Communication with Distributed Alignment Sensing for Origami Biomedical Abstract--Origami implant design is a 3D integration tech- nique which addresses size and cost constraints configuration inside the body, allowing minimally- invasive surgery [4]. Other applications of this Origami

  14. Scaffolding Critical Thinking in the Zone of Proximal Development

    ERIC Educational Resources Information Center

    Wass, Rob; Harland, Tony; Mercer, Alison

    2011-01-01

    This paper explores student experiences of learning to think critically. Twenty-six zoology undergraduates took part in the study for three years of their degree at the University of Otago, New Zealand. Vygotsky's developmental model of the Zone of Proximal Development (ZPD) provided a framework as we examined how critical thinking was developed.…

  15. Sharpening a Tool for Teaching: The Zone of Proximal Development

    ERIC Educational Resources Information Center

    Wass, Rob; Golding, Clinton

    2014-01-01

    Vygotsky's Zone of Proximal Development (ZPD) provides an important understanding of learning, but its implications for teachers are often unclear or limited and could be further explored. We use conceptual analysis to sharpen the ZPD as a teaching tool, illustrated with examples from teaching critical thinking in zoology. Our conclusions are…

  16. On the Least Cost for Proximity Searching in Metric Spaces

    Microsoft Academic Search

    Karina Figueroa; Edgar Chávez; Gonzalo Navarro; Rodrigo Paredes

    2006-01-01

    Proximity searching consists in retrieving from a database those elements that are similar to a query. As the distance is usually expensive to compute, the goal is to use as few distance computations as possible to satisfy queries. Indexes use precomputed distances among database elements to speed up queries. As such, a baseline is AESA, which stores all the distances

  17. Characterization of printed UWB antennas in proximity of human head

    Microsoft Academic Search

    Ailian Cai; Zhi Ning Chen

    2005-01-01

    This paper characterizes the ultra-wideband (UWB) antennas in proximity of human head using an FDTD method. In the study, a numerical head model of frequency dependent dielectric constant and conductivity is used. The performance of the antennas printed on PCB is investigated in terms of the impedance matching, radiation patterns, and gain. The information derived from this study is conductive

  18. Performance-driven optical proximity correction for mask cost reduction

    E-print Network

    Kahng, Andrew B.

    correction OPC are an integral part of the design to mask flow. OPC creates complex features to the layout, as seen in the inte- grated circuits IC layout editor, grow tremendously due to subresolution assistPerformance-driven optical proximity correction for mask cost reduction Puneet Gupta Blaze DFM

  19. The impact of illuminator signatures on optical proximity effects

    NASA Astrophysics Data System (ADS)

    Tyminski, Jacek K.; Renwick, Stephen P.

    2008-11-01

    Low pass filtering taking place in the projection tools used by the IC industry leads to a range of optical proximity effects, OPEs, resulting in undesired characteristics of patterns projected by the scanners. Commonly used scanner imaging models are capable of capturing OPEs driven by the fundamental imaging conditions such as wavelength, illuminator layout, reticle technology, and lens numerical aperture.

  20. Rendezvous and Proximity Operations of the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Goodman, John L.

    2005-01-01

    Space Shuttle rendezvous missions present unique challenges that were not fully recognized when the Shuttle was designed. Rendezvous targets could be passive (i.e., no lights or transponders), and not designed to facilitate Shuttle rendezvous, proximity operations, and retrieval. Shuttle reaction control system jet plume impingement on target spacecraft presented induced dynamics, structural loading, and contamination concerns. These issues, along with limited reaction control system propellant in the Shuttle nose, drove a change from the legacy Gemini/Apollo coelliptic profile to a stable orbit profile, and the development of new proximity operations techniques. Multiple scientific and on-orbit servicing missions, and crew exchange, assembly and replenishment flights to Mir and to the International Space Station drove further profile and piloting technique changes. These changes included new proximity operations, relative navigation sensors, and new computer generated piloting cues. However, the Shuttle's baseline rendezvous navigation system has not required modification to place the Shuttle at the proximity operations initiation point for all rendezvous missions flown.

  1. Proximate Causes of Two Types of AB Questions

    E-print Network

    Brown, Christopher A.

    Nervous system has fast response but shorter duration Endocrine system has slower response but longer Proximate Factors Hormones Nervous system Genes Environment Parasites/symbionts #12;3 Hormones & Behavior Hormones are chemical signaling molecules that travel through blood (or other fluid) Come from: Endocrine

  2. Nephrocalcinosis in glucose-galactose malabsorption: nephrocalcinosis and proximal tubular dysfunction in a young infant with a novel mutation of SGLT1

    Microsoft Academic Search

    Özlem Bekem Soylu; Çi?dem Ecevit; Serdar Alt?nöz; Aysel Aydo?an Öztürk; Ali Kemal Temizkan; Mari Maeda; Michihiro Kasahara

    2008-01-01

    We report an association of proximal renal tubular dysfunction in a 50-day-old girl with glucose-galactose malabsorption who\\u000a was found to have nephrocalcinosis, but no sign of nephrolithiasis. A novel homozygous nonsense mutation at 267Arg ?stop (CGA?TGA)\\u000a in the Na+-dependent glucose transporter (SGLT1) was found in loop 5 connecting transmembrane segments 6 and 7, indicating the complete\\u000a loss of glucose transport

  3. Models for coupling of salt and water transport; Proximal tubular reabsorption in Necturus kidney

    PubMed Central

    Sackin, H; Boulpaep, EL

    1975-01-01

    Models for coupling of salt and water transport are developed with two important assumptions appropriate for leaky epithelia. (a) The tight junction is permeable to both sale and water. (b) Active Na transport into the lateral speces is assumed to occur uniformly along the length of the channel. The proposed models deal specifically with the intraepithelial mechanism of proximal tubular resbsorption in the Necturus kidney although they have implications for epithelial transport in the gallbladder and small intestine as well. The first model (continuous version) is similar to the standing gradient model devised by Diamond and Bossert but used different boundary conditions. In contrast to Diamond and Bossert's model, the predicted concentration profiles are relatively flat with no sizable gradients along the interspace. The second model (compartment version) expands Curran's model of epithelial salt and water transport by including additional compartments and considering both electrical and chemical driving forces for individual Na and Cl ions as well as hydraulic and osmotic driving forces for water. In both models, ion and water fluxes are investigated as a function of the transport parameters. The behavior of the models is consistent with previously suggested mechanisms for the control of net transport, particularly during saline diuresis. Under all conditions the predicted ratio of net solute to solvent flux, or emergent concentration, deviates from exact isotonicity (except when the basement membrane has an appreciable salt reflection coefficient). However, the degree of hypertonicity may be small enough to be experimentally indistinguishable from isotonic transport. PMID:1104761

  4. Activation of D4 dopamine receptor decreases angiotensin II type 1 receptor expression in rat renal proximal tubule cells.

    PubMed

    Chen, Ken; Deng, Kun; Wang, Xiaoyan; Wang, Zhen; Zheng, Shuo; Ren, Hongmei; He, Duofen; Han, Yu; Asico, Laureano D; Jose, Pedro A; Zeng, Chunyu

    2015-01-01

    The dopaminergic and renin-angiotensin systems interact to regulate blood pressure. Disruption of the D4 dopamine receptor gene in mice produces hypertension that is associated with increased renal angiotensin type 1 (AT1) receptor expression. We hypothesize that the D4 receptor can inhibit AT1 receptor expression and function in renal proximal tubule cells from Wistar-Kyoto (WKY) rats, but the D4 receptor regulation of AT1 receptor is aberrant in renal proximal tubule cells from spontaneously hypertensive rats (SHRs). The D4 receptor agonist, PD168077, decreased AT1 receptor protein expression in a time- and concentration-dependent manner in WKY cells. By contrast, in SHR cells, PD168077 increased AT1 receptor protein expression. The inhibitory effect of D4 receptor on AT1 receptor expression in WKY cells was blocked by a calcium channel blocker, nicardipine, or calcium-free medium, indicating that calcium is involved in the D4 receptor-mediated signaling pathway. Angiotensin II increased Na(+)-K(+) ATPase activity in WKY cells. Pretreatment with PD168077 decreased the stimulatory effect of angiotensin II on Na(+)-K(+) ATPase activity in WKY cells. In SHR cells, the inhibitory effect of D4 receptor on angiotensin II-mediated stimulation of Na(+)-K(+) ATPase activity was aberrant; pretreatment with PD168077 augmented the stimulatory effect of AT1 receptor on Na(+)-K(+) ATPase activity in SHR cells. This was confirmed in vivo; pretreatment with PD128077 for 1 week augmented the antihypertensive and natriuretic effect of losartan in SHRs but not in WKY rats. We suggest that an aberrant interaction between D4 and AT1 receptors may play a role in the abnormal regulation of sodium excretion in hypertension. PMID:25368031

  5. Proximity and the Evolution of Collaboration Networks: Evidence from Research and

    E-print Network

    Balland, Pierre-Alexandre

    leurs partenaires en fonction de leur proximité géographique, cognitive, organisationnelle their partners according to their geographical, cognitive, organizational, institutional and social proximity collaborations, while cognitive and social proximity do not play a significant role. Collaboration networks

  6. Proximity nanovalve with large phase-tunable thermal conductance

    SciTech Connect

    Strambini, E., E-mail: e.strambini@sns.it; Giazotto, F., E-mail: f.giazotto@sns.it [NEST Istituto Nanoscienze-CNR and Scuola Normale Superiore, I-56127 Pisa (Italy); Bergeret, F. S., E-mail: sebastian-bergeret@ehu.es [Centro de Física de Materiales (CFM-MPC), Centro Mixto CSIC-UPV/EHU, Manuel de Lardizabal 4, E-20018 San Sebastián (Spain); Donostia International Physics Center (DIPC), Manuel de Lardizabal 5, E-20018 San Sebastián (Spain); Institut für Physik, Carl von Ossietzky Universität, D-26111 Oldenburg (Germany)

    2014-08-25

    We propose a phase-controlled heat-flux quantum valve based on the proximity effect driven by a superconducting quantum interference proximity transistor (SQUIPT). Its operation relies on the phase-dependent quasiparticle density of states in the Josephson weak-link of the SQUIPT which controls thermal transport across the device. In a realistic Al/Cu-based setup the structure can provide efficient control of thermal current inducing temperature swings exceeding ?100?mK, and flux-to-temperature transfer coefficients up to ?500?mK/?{sub 0} below 100?mK. The nanovalve performances improve by lowering the bath temperature, making the proposed structure a promising building-block for the implementation of coherent caloritronic devices operating below 1?K.

  7. Aircraft Proximity Maps Based on Data-Driven Flow Modeling

    E-print Network

    Salaün, Erwan; Vela, Adan; Feron, Eric

    2011-01-01

    With the forecast increase in air traffic demand over the next decades, it is imperative to develop tools to provide traffic flow managers with the information required to support decision making. In particular, decision-support tools for traffic flow management should aid in limiting controller workload and complexity, while supporting increases in air traffic throughput. While many decision-support tools exist for short-term traffic planning, few have addressed the strategic needs for medium- and long-term planning for time horizons greater than 30 minutes. This paper seeks to address this gap through the introduction of 3D aircraft proximity maps that evaluate the future probability of presence of at least one or two aircraft at any given point of the airspace. Three types of proximity maps are presented: presence maps that indicate the local density of traffic; conflict maps that determine locations and probabilities of potential conflicts; and outliers maps that evaluate the probability of conflict due t...

  8. Scintillation proximity radioimmunoassay utilizing 125I-labeled ligands

    SciTech Connect

    Udenfriend, S.; Gerber, L.D.; Brink, L.; Spector, S.

    1985-12-01

    A unique type of radioimmunoassay is described that does not require centrifugation or separation. Microbeads containing a fluorophor are covalently linked to antibody. When an /sup 125/I-labeled antigen is added it binds to the beads and, by its proximity, the emitted short-range electrons of the /sup 125/I excite the fluorophor in the beads. The light emitted can be measured in a standard scintillation counter. Addition of unlabeled antigen from tissue extracts displaces the labeled ligand and diminishes the fluorescent signal. Application of scintillation proximity immunoassay to tissue enkephalins, serum thyroxin, and urinary morphine is described. Applications of the principle to study the kinetics of interaction between receptors and ligands are discussed.

  9. Longitudinal proximity effects in superconducting transition-edge sensors.

    PubMed

    Sadleir, John E; Smith, Stephen J; Bandler, Simon R; Chervenak, James A; Clem, John R

    2010-01-29

    We have found experimentally that the critical current of a square thin-film superconducting transition-edge sensor (TES) depends exponentially upon the side length L and the square root of the temperature T, a behavior that has a natural theoretical explanation in terms of longitudinal proximity effects if the TES is regarded as a weak link between superconducting leads. As a consequence, the effective transition temperature T{c} of the TES is current dependent and at fixed current scales as 1/L{2}. We have also found that the critical current can show clear Fraunhofer-like oscillations in an applied magnetic field, similar to those found in Josephson junctions. We have observed the longitudinal proximity effect in these devices over extraordinarily long lengths up to 290 microm, 1450 times the mean-free path. PMID:20366733

  10. Space station proximity operations windows: Human factors design guidelines

    NASA Technical Reports Server (NTRS)

    Haines, Richard F.

    1987-01-01

    Proximity operations refers to all activities outside the Space Station which take place within a 1-km radius. Since there will be a large number of different operations involving manned and unmanned vehicles, single- and multiperson crews, automated and manually controlled flight, a wide variety of cargo, and construction/repair activities, accurate and continuous human monitoring of these operations from a specially designed control station on Space Station will be required. Total situational awareness will be required. This paper presents numerous human factors design guidelines and related background information for control windows which will support proximity operations. Separate sections deal with natural and artificial illumination geometry; all basic rendezvous vector approaches; window field-of-view requirements; window size; shape and placement criteria; window optical characteristics as they relate to human perception; maintenance and protection issues; and a comprehensive review of windows installed on U.S. and U.S.S.R. manned vehicles.

  11. Disproportionate Proximity to Environmental Health Hazards: Methods, Models, and Measurement

    PubMed Central

    Maantay, Juliana A.; Brender, Jean D.

    2011-01-01

    We sought to provide a historical overview of methods, models, and data used in the environmental justice (EJ) research literature to measure proximity to environmental hazards and potential exposure to their adverse health effects. We explored how the assessment of disproportionate proximity and exposure has evolved from comparing the prevalence of minority or low-income residents in geographic entities hosting pollution sources and discrete buffer zones to more refined techniques that use continuous distances, pollutant fate-and-transport models, and estimates of health risk from toxic exposure. We also reviewed analytical techniques used to determine the characteristics of people residing in areas potentially exposed to environmental hazards and emerging geostatistical techniques that are more appropriate for EJ analysis than conventional statistical methods. We concluded by providing several recommendations regarding future research and data needs for EJ assessment that would lead to more reliable results and policy solutions. PMID:21836113

  12. Partial claviculectomy after non-union of proximal clavicle fracture.

    PubMed

    Teng, Hsiu-Gwo; Liu, Andy Li-Jen

    2013-01-01

    Non-union of a proximal clavicle fracture is rare. When it does occur, it poses a difficult problem causing severe pain and shoulder impairment that must be dealt with surgically. We report a 29-year-old woman who suffered a proximal clavicle fracture and received plate and screws fixation. Six months later, after constant pain and a diminished range of shoulder motion, she sought help at our clinic and was diagnosed with symptomatic non-union. Reconstruction with bone graft and interosseous sutures was performed in vain as pain persisted and follow-up radiograph showed no healing. A salvage procedure with partial claviculectomy was then carried out. The patient has been pain free after 3.5 years of follow-up, a full range of motion and is quite satisfied with the cosmetics. This outcome demonstrates that claviculectomy can be used successfully in a clinical situation where restoration of clavicular non-union fails. PMID:23542725

  13. Partial claviculectomy after non-union of proximal clavicle fracture

    PubMed Central

    Teng, Hsiu-Gwo; Liu, Andy Li-Jen

    2013-01-01

    Non-union of a proximal clavicle fracture is rare. When it does occur, it poses a difficult problem causing severe pain and shoulder impairment that must be dealt with surgically. We report a 29-year-old woman who suffered a proximal clavicle fracture and received plate and screws fixation. Six months later, after constant pain and a diminished range of shoulder motion, she sought help at our clinic and was diagnosed with symptomatic non-union. Reconstruction with bone graft and interosseous sutures was performed in vain as pain persisted and follow-up radiograph showed no healing. A salvage procedure with partial claviculectomy was then carried out. The patient has been pain free after 3.5?years of follow-up, a full range of motion and is quite satisfied with the cosmetics. This outcome demonstrates that claviculectomy can be used successfully in a clinical situation where restoration of clavicular non-union fails. PMID:23542725

  14. Human exploration of near Earth Asteroids: Architecture of proximity operations

    NASA Astrophysics Data System (ADS)

    Tardivel, Simon; Takahashi, Yu; Zimmer, Aline K.; Herman, Jonathan F. C.; Reijneveld, Johannes P. J.; Dunlop, Kathryn L.; Scheeres, Daniel J.

    2015-05-01

    This paper outlines the strategic approach to realize a human mission to an asteroid, focusing specifically on the proximity operations. The risks and challenges posed by asteroid surfaces to in-situ investigations force the proximity operations to be done by the intermediary of robotic explorers. In this architecture, a precursor is sent years in advance to a potential target asteroids. Its main goals are the characterization of the gravity field and of the surface behavior. If the target is found suitable, the manned mission then proceeds. With their main spacecraft stationed on a stable orbit around the asteroid, the astronauts are transported to the surface via a small, unpressurized spacecraft. Hovering a few meters above the surface, they deploy and command small robotic landers that perform scientific operations at the surface.

  15. Proximity-induced pseudogap: evidence for preformed pairs.

    PubMed

    Yuli, Ofer; Asulin, Itay; Kalcheim, Yoav; Koren, Gad; Millo, Oded

    2009-11-01

    The temperature evolution of the proximity effect in Au/La(2-x)Sr(x)CuO(4) and La(1.55)Sr(0.45)CuO(4)/La(2-x)Sr(x)CuO(4) bilayers was investigated using scanning tunneling microscopy. Proximity-induced gaps, centered at the chemical potential, were found to persist above the superconducting transition temperature, T(c), and up to nearly the pseudogap crossover temperature in both systems. Such independence of the spectra on the details of the normal-metal cap layer is incompatible with a density-wave order origin. However, our results can be accounted for by a penetration of incoherent Cooper pairs into the normal metal above T(c). PMID:20365947

  16. Rendezvous and Proximity Operations of the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Goodman, John L.

    2005-01-01

    Space Shuttle rendezous missions presented unique challenges that were not fully recognized when the Shuttle was designed. Rendezvous targets could be passive (i.e., no lights or transponders), and not designed to facilitate Shuttle rendezvous, proximity operations and retrieval. Shuttle reaction control system jet plume impingement on target spacecraft presented induced dynamics, structural loading and contamination concerns. These issues, along with limited forward reaction control system propellant, drove a change from the Gemimi/Apollo coelliptic profile heritage to a stable orbit profile, and the development of new proximity operations techniques. Multiple scientific and on-orbit servicing missions and crew exchange, assembly and replinishment flights to Mir and to the International Space Station drove further profile and piloting technique changes, including new relative navigation sensors and new computer generated piloting cues.

  17. Real-time algorithm for surface inspection using proximity data

    NASA Astrophysics Data System (ADS)

    Ip, Horace H. S.

    1993-01-01

    This paper presents a real time inspection algorithm of fuel pellet surface. The algorithm identifies the different types of surface features of the pellets from sensed data derived from an array of proximity sensors. The algorithm meets the operating requirements in terms of speed and accuracy and can be implemented using relatively simple hardware. The development also includes a sensed data visualization tool which facilitates the analysis of the performance of the algorithm.

  18. Improvement of Negative Bias Temperature Instability by Stress Proximity Technique

    Microsoft Academic Search

    Jian Bo Yang; T. P. Chen; Ying Gong; Shyue Seng Tan; Chee Mang Ng; Lap Chan

    2010-01-01

    The stress proximity technique (SPT) is found to improve negative bias temperature instability (NBTI) in p-channel metal-oxide-semiconductor field-effect transistors significantly. A first-principles calculation is carried out to examine the effect of strain on NBTI, and a process simulation is conducted to determine the change in stress profile in the device induced by SPT. The first-principles calculation shows that a larger

  19. Impact of Proximal Colon Retroflexion on Adenoma Miss Rates

    Microsoft Academic Search

    Matthew Harrison; Navjot Singh; Douglas K. Rex

    2004-01-01

    BACKGROUND:Small adenomas are commonly missed during routine colonoscopy. The aim of this study was to determine whether routine retroflexion in the proximal colon would improve adenoma detection rates.METHODS:One hundred patients underwent colonoscopy from the cecum to the splenic flexure by a gastroenterology fellow, with the removal of all visualized polyps. The cecum was then reintubated and patients were randomized to

  20. Chloride transport in human proximal colonic apical membrane vesicles

    Microsoft Academic Search

    Ravish J. Mahajan; Melissa L. Baldwin; James M. Harig; Krishnamurthy Ramaswamy; Pradeep K. Dudeja

    1996-01-01

    The mechanism(s) of Cl? transport across the human colonic apical membranes are not well understood. Apical membrane vesicles (AMV) purified from organ donor proximal colonic mucosa and a rapid millipore filtration technique were utilized to study 36Cl? uptake into these vesicles. Outwardly directed OH? and HCO3? gradient stimulated 36Cl? uptake into these vesicles demonstrating a transient accumulation over equilibrium uptake.

  1. Ultrastructure of the grasshopper proximal femoral chordotonal organ

    Microsoft Academic Search

    D. T. Moran; J. C. Rowley; F. G. Varela

    1975-01-01

    This paper, the first in a series concerning the neurobiology of sensory cilia, describes the ultrastructure of our chosen model system—the proximal femoral chordotonal organ (FCO) in pro-and mesothoracic grasshopper legs. The FCO is a bundle of 150–200 longitudinally oriented chordotonal sensilla. Each chordotonal sensillum is a mechano-receptive unit that contains two bipolar neurons whose dendrites bear sensory cilia. The

  2. Thermal Conductance by the Inverse Proximity Effect in a Superconductor

    NASA Astrophysics Data System (ADS)

    Peltonen, J. T.; Virtanen, P.; Meschke, M.; Koski, J. V.; Heikkilä, T. T.; Pekola, J. P.

    2010-08-01

    We study heat transport in hybrid lateral normal-metal-superconductor-normal-metal structures. We find the thermal conductance of a short superconducting wire to be strongly enhanced beyond the BCS value due to the inverse proximity effect, resulting from contributions of elastic cotunneling and crossed Andreev reflection of quasiparticles. Our measurements agree with a model based on the quasiclassical theory of inhomogeneous superconductivity in the diffusive limit.

  3. Complex of myoglobin with phenol bound in a proximal cavity

    PubMed Central

    Huang, Xiao; Wang, Chunxue; Celeste, Lesa R.; Lovelace, Leslie L.; Sun, Shenfang; Dawson, John H.; Lebioda, Lukasz

    2012-01-01

    Sperm whale myoglobin (Mb) has weak dehaloperoxidase activity and catalyzes the peroxidative dehalogenation of 2,4,6-trichlorophenol (TCP) to 2,6-dichloroquinone. Crystals of Mb and of its more active G65T variant were used to study the binding of TCP, 4-iodophenol (4-IP) and phenol. The structures of crystals soaked overnight in a 10?mM solution of phenol revealed that a phenol molecule binds in the proximal cavity, forming a hydrogen bond to the hydroxyl of Tyr146 and hydrophobic contacts which include interactions with C? and C? of the proximal histidine His93. The phenol position corresponds to the strongest xenon binding site, Xe1. It appears that the ligand enters the proximal cavity through a gate formed by the flexible loops 79–86 and 93–103. TCP and 4-­IP do not bind to Mb in this manner under similar conditions; however, it appears to be likely that dimethyl sulfoxide (DMSO), which was used at a concentration of 0.8?M to facilitate 4-IP dissolution, binds in the phenol/Xe1 binding site. In this structure, a water molecule coordinated to the heme iron was replaced by an oxygen molecule, reflecting the reduction of the heme. Crystals of Mb and G65T Mb soaked for 5–10?min did not show bound phenol. Kinetic studies of TCP dechlorination showed that phenol has a dual effect: it acts as a competitive inhibitor that is likely to interfere with TCP binding at the heme edge and as a weak activator, likely through binding in the proximal cavity. The lack of phenol bound at the heme edge in the crystal structures suggests that its inhibitory binding only takes place when the heme is activated by hydrogen peroxide. PMID:23192025

  4. Neurons, potassium, and glia in proximal retina of Necturus

    Microsoft Academic Search

    CHESTER J. KARWOSKI; LUIS M. PROENZA

    1980-01-01

    Light-evoked K + flux and intracellular Miiller (glial) cell and on\\/off-neuron responses were recorded from the proximal retina of Necturus in eyecups from which the vitreous was not drained. On\\/off-responses, probably arising from amacrine cells, showed an initial transient and a sustained com- ponent that always exhibited surround antagonism. Miiller cell responses were small but otherwise similar to those recorded

  5. Complex of myoglobin with phenol bound in a proximal cavity.

    PubMed

    Huang, Xiao; Wang, Chunxue; Celeste, Lesa R; Lovelace, Leslie L; Sun, Shenfang; Dawson, John H; Lebioda, Lukasz

    2012-12-01

    Sperm whale myoglobin (Mb) has weak dehaloperoxidase activity and catalyzes the peroxidative dehalogenation of 2,4,6-trichlorophenol (TCP) to 2,6-dichloroquinone. Crystals of Mb and of its more active G65T variant were used to study the binding of TCP, 4-iodophenol (4-IP) and phenol. The structures of crystals soaked overnight in a 10?mM solution of phenol revealed that a phenol molecule binds in the proximal cavity, forming a hydrogen bond to the hydroxyl of Tyr146 and hydrophobic contacts which include interactions with C? and C? of the proximal histidine His93. The phenol position corresponds to the strongest xenon binding site, Xe1. It appears that the ligand enters the proximal cavity through a gate formed by the flexible loops 79-86 and 93-103. TCP and 4-IP do not bind to Mb in this manner under similar conditions; however, it appears to be likely that dimethyl sulfoxide (DMSO), which was used at a concentration of 0.8?M to facilitate 4-IP dissolution, binds in the phenol/Xe1 binding site. In this structure, a water molecule coordinated to the heme iron was replaced by an oxygen molecule, reflecting the reduction of the heme. Crystals of Mb and G65T Mb soaked for 5-10?min did not show bound phenol. Kinetic studies of TCP dechlorination showed that phenol has a dual effect: it acts as a competitive inhibitor that is likely to interfere with TCP binding at the heme edge and as a weak activator, likely through binding in the proximal cavity. The lack of phenol bound at the heme edge in the crystal structures suggests that its inhibitory binding only takes place when the heme is activated by hydrogen peroxide. PMID:23192025

  6. Metacognition of agency: proximal action and distal outcome.

    PubMed

    Metcalfe, Janet; Eich, Teal S; Miele, David B

    2013-09-01

    The cues contributing to people's metacognitions of agency were investigated in two experiments in which people played a computer game that involved trying to "touch", via a mouse moving a cursor, downward scrolling X's (Experiment 1), or trying to "explode" the downward scrolling X's (Experiment 2). Both experiments varied (a) proximal action-related information by either introducing or not introducing Turbulence into the mouse controls and (b) distal outcome-related information such that touched X's "exploded" either 100 or 75 % of the time. Both variables affected people's judgments of agency (JOAs), but the effect was different. First, the decrement in feelings of agency was greater with the proximal variable than with distal variable. Second, while the proximal variable always had a large direct effect on JOAs, even taking judgments of performance (JOPs) into account, JOPs completely accounted for the effect of the distal variable in Experiment 1, where the instructions were just to touch the X's. And even in Experiment 2, in which the instructions were to explode the X's, the direct effect of the distal variable on JOAs was small. These data indicate that these two cues exhibit different psychological profiles. The proximal action-related information is a diagnostic cue to agency indicating the match between one's own intentions and actions. Internal monitoring of intentions is necessary and so the self is implicated. However, distal outcome can be largely monitored using information external to the agent, and so-while it is used by people to make agency judgments-it is a non-diagnostic cue. PMID:23358706

  7. Tyrosine phosphorylation profiling via in situ proximity ligation assay

    PubMed Central

    2014-01-01

    Background Tyrosine phosphorylation (pTyr) is an important cancer relevant posttranslational modification since it regulates protein activity and cellular localization. By controlling cell growth and differentiation it plays an important role in tumor development. This paper describes a novel approach for detection and visualization of a panel of pTyr proteins in tumors using in situ proximity ligation assay. Methods K562 leukemia cells were treated with tyrosine kinase and/or phosphatase inhibitors to induce differences in pTyr levels and mimic cells with different malignant properties. Cells were then probed with one antibody against the pTyr modification and another probe against the detected protein, resulting in a detectable fluorescent signal once the probes were in proximity. Results Total and protein specific pTyr levels on ABL, SHC, ERK2 and PI3K proteins were detected and samples of control and treated cells were distinguished at the pTyr level using this novel approach. Promising results were also detected for formalin fixed and paraffin embedded cells in the micro array format. Conclusions This application of in situ proximity ligation assay is valuable in order to study the pTyr modification of a panel of proteins in large data sets to validate mass spectrometric data and to be combined with tissue microarrays. The approach offers new opportunities to reveal the pTyr signatures in cells of different malignant properties that can be used as biomarker of disease in the future. PMID:24928687

  8. Proximal femur segmentation in conventional pelvic x ray

    SciTech Connect

    Pilgram, Roland; Walch, Claudia; Kuhn, Volker; Schubert, Rainer; Staudinger, Roland [Institute of Applied Systems Research and Development, University for Health Sciences, Medical Informatics and Technology (UMIT), 6060 Hall in Tyrol (Austria) and Institute of Biomedical Image Analysis, University for Health Sciences, Medical Informatics and Technology (UMIT) (Austria); Department of Radiology, Medical University of Innsbruck (Austria); Department of Trauma Surgery and Sport Traumatology, Medical University of Innsbruck (Austria); Institute of Biomedical Image Analysis, University for Health Sciences, Medical Informatics and Technology (UMIT) (Austria); Institute of Applied Systems Research and Development, University for Health Sciences, Medical Informatics and Technology, 6060 Hall in Tyrol (Austria)

    2008-06-15

    A solid and accurate proximal femur segmentation technique using the popular active shape model (ASM) is proposed. For generating an optimal shape prior, the minimum description length, based on 200 supervised manual segmented proximal femur shapes, is used. The segmentation is based on a coarse to fine scaling technique including a profile scale space method. The segmentation results are compared using an optimal defined initial pose and a pose based on a registration technique. Using ideal template initialization, 95% of the shapes have been recovered exactly (average point-to-point error {approx}13 pixels, average point-to-boundary error {approx}7 pixels). Using a template-based initialization based on a registration technique, a successful segmentation rate of {approx}89% is achieved, with an average point-to-point error {approx}12 pixels, and an average point-to-boundary error {approx}8 pixels. With an adequate template initialization and an improved ASM, this method seems to provide an accurate tool for segmentation of the proximal femur shapes on conventional hip overview x-ray images.

  9. Failure to demonstrate a hormonal inhibitor of proximal sodium reabsorption

    PubMed Central

    Wright, Fred S.; Brenner, Barry M.; Bennett, Cleaves M.; Keimowitz, Robert I.; Berliner, Robert W.; Schrier, Robert W.; Verroust, Pierre J.; De Wardener, Hugh E.; Holzgreve, Heinz

    1969-01-01

    Recently, it has been reported that a humoral inhibitor of proximal sodium reabsorption could be detected in plasma, and dialysates of plasma, of rats and dogs undergoing saline diuresis. We have repeated these studies using similar techniques and protocols. Fractional sodium reabsorption by the proximal tubule (as estimated in free-flow micropuncture studies from tubule fluid-to-plasma inulin ratios) was found not to be lower during infusion of “natriuretic” plasma than during subsequent infusion of “hydropenic” plasma. Similarly, infusion of natriuretic plasma failed to prolong reabsorptive half-time of the shrinking drop beyond that seen during hydropenic plasma infusion. No increase in urine volume or rate of sodium excretion was observed during the period of natriuretic plasma infusion, nor did natriuretic plasma result in an increase in these measures in rats undergoing water diuresis. It also has been reported that dialysates of natriuretic plasma, but not of hydropenic plasma, when placed directly into the tubule lumen, inhibit proximal sodium reabsorption. In double blind studies carried out independently in Bethesda, London, and Cologne, we failed to detect the presence of a dialyzable inhibitor in natriuretic plasma. Finally, in contrast to other recent reports, we were unable to detect inhibitory activity in plasma obtained from dogs during the “escape” phase of chronic deoxycorticosterone acetate administration. PMID:5771192

  10. Thrust Characteristics of Multiple Lifting Jets in Ground Proximity

    NASA Technical Reports Server (NTRS)

    Davenport, Edwin E.; Spreeman, Kenneth P.

    1960-01-01

    An investigation has been made to determine the thrust characteristics within ground proximity of a series of models which might represent vertical take-off-and-landing (VTOL) aircraft with multiple exit jet engines exhausting vertically downward beneath a lifting surface. Variations in simulated engine configurations were provided by a series of nozzle insert plugs in which the number of jet exits, located symmetrically on a fixed circle, was varied, or the diameter of the circle was varied for a given number of jet exits. represent lifting surfaces, and high-pressure air was used to simulate jet-engine exhaust. Plywood plates were used to The results of the investigation showed that increasing the number of exits, such that an annular jet configuration was approached, provided more favorable thrust characteristics within ground proximity than any other variation in the geometry of these multiple jets. Tests of a configuration with two nozzles approximating a fan-in-wing VTOL aircraft with fans located at different spanwise locations indicated that the augmentation in thrust within ground proximity was greater for the arrangement with the more inboard location of the nozzles.

  11. Proximity-dependent inhibition in Escherichia coli isolates from cattle.

    PubMed

    Sawant, Ashish A; Casavant, N Carol; Call, Douglas R; Besser, Thomas E

    2011-04-01

    We describe a novel proximity-dependent inhibition phenotype of Escherichia coli that is expressed when strains are cocultured in defined minimal media. When cocultures of "inhibitor" and "target" strains approached a transition between logarithmic and stationary growth, target strain populations rapidly declined >4 log CFU per ml over a 2-h period. Inhibited strains were not affected by exposure to conditioned media from inhibitor and target strain cocultures or when the inhibitor and target strains were incubated in shared media but physically separated by a 0.4-?m-pore-size membrane. There was no evidence of lytic phage or extracellular bacteriocin involvement, unless the latter was only present at effective concentrations within immediate proximity of the inhibited cells. The inhibitory activity observed in this study was effective against a diversity of E. coli strains, including enterohemorrhagic E. coli serotype O157:H7, enterotoxigenic E. coli expressing F5 (K99) and F4 (K88) fimbriae, multidrug-resistant E. coli, and commensal E. coli. The decline in counts of target strains in coculture averaged 4.8 log CFU/ml (95% confidence interval, 4.0 to 5.5) compared to their monoculture counts. Coculture of two inhibitor strains showed mutual immunity to inhibition. These results suggest that proximity-dependent inhibition can be used by bacteria to gain a numerical advantage when populations are entering stationary phase, thus setting the stage for a competitive advantage when growth conditions improve. PMID:21296941

  12. Adult proximity and frugivore's activity structure the spatial pattern in an endangered plant

    E-print Network

    Traveset, Anna

    Adult proximity and frugivore's activity structure the spatial pattern in an endangered plant, (ii) disperser activity, (iii) proximity of adults on the distribution of juvenile and adult shrubs and (iv) the impact of adult proximity on juvenile survival. 4. Plants were aggregated in all populations

  13. Parametric behavior of the optimal control solution for collision avoidance in a close proximity encounter

    Microsoft Academic Search

    N. Fulton

    2009-01-01

    This paper studies close proximity aircraft encounters that can occur in the missed-approach, in the circuit area, and for operations outside controlled airspace where air traffic management services may be unavailable and where aircraft may routinely fly in close proximity. The paper presents a synthesis of optimal control for cooperative collision avoidance strategies in a close proximity coplanar encounter and

  14. Foreign Direct Investment, Intra-organizational Proximity, and Technological Capability: The Case of China's Automobile Industry

    E-print Network

    Foreign Direct Investment, Intra-organizational Proximity, and Technological Capability: The Case parents . #12;4 #12;5 Foreign Direct Investment, Intra-organizational Proximity, and Technological direct investment (FDI), intra-organizational proximity, and in-house technology development performances

  15. Research on the virtual simulation and testing technology of capacitance proximity fuze

    Microsoft Academic Search

    Chengtian Song; Yuxian Bai; Keyong Wang

    2008-01-01

    Simulation technology of capacitance proximity fuze plays a very important role in the development and application of capacitance proximity fuze. In this paper, the simulation principle of capacitance proximity fuze is analysed. The hardware of simulation and testing system is designed, which is constituted of demodulation signal output circuit, interface circuit and signal regulation circuit. The virtual simulation and testing

  16. Transtubular oncotic pressure gradients and net fluid transport in isolated proximal tubules

    Microsoft Academic Search

    Masashi Imai; Juha P Kokko

    1974-01-01

    Transtubular oncotic pressure gradients and net fluid transport in isolated proximal tubules. A number of studies have shown that peritubular oncotic forces can directly affect net transport of fluid out of the renal proximal tubule. In our previous report it was shown that peritubular protein concentration does influence net reabsorption out of the isolated perfused proximal convoluted tubule (PCT) without

  17. Deriving the number of jobs in proximity services from the number of inhabitants in French rural

    E-print Network

    Paris-Sud XI, Université de

    Deriving the number of jobs in proximity services from the number of inhabitants in French rural a minimum requirement approach to derive the number of jobs of proximity services per inhabitant observe that the minimum number of service jobs per inhabitant (interpreted as jobs of proximity services

  18. Message propagation in ad-hoc-based proximity mobile social networks

    Microsoft Academic Search

    Wenbo He; Ying Huang; Klara Nahrstedt; Bo Wu

    2010-01-01

    The proximity service using Bluetooth and\\/or P2P WIFI enabled mobile devices for people's social interactions with other users who come into their close proximity is becoming an important means for people to conveniently and efficiently expand their social networks. Proximity mobile social networks (PMSNs) are usually built in ad hoc mode to allow information sharing and interaction among users in

  19. Biotin uptake by human proximal tubular epithelial cells: cellular and molecular aspects.

    PubMed

    Balamurugan, Krishnaswamy; Vaziri, Nosratola D; Said, Hamid M

    2005-04-01

    Cellular and molecular regulation of renal biotin uptake in humans is not well defined. The contribution of the human Na(+)-dependent multivitamin transporter (hSMVT) to carrier-mediated biotin uptake by human proximal tubular epithelial cells is not clear. The aim of this study was to address these issues, with the human-derived proximal tubular epithelial HK-2 cells used as a model. First, we characterized the mechanism of biotin uptake by these cells and obtained evidence for involvement of an Na(+)-, temperature-, and energy-dependent carrier-mediated uptake system. This system was inhibited by the biotin structural analog desthiobiotin, pantothenic acid, and lipoate. These findings suggest involvement of the hSMVT system in the uptake process. This was confirmed by demonstrating that the hSMVT system is expressed in HK-2 cells at the protein and mRNA levels and by selective silencing of the hSMVT gene with the use of gene-specific small interfering RNAs, which led to specific and significant inhibition of carrier-mediated biotin uptake. Of the two recently cloned promoters of the hSMVT gene, promoter 1 was more active than promoter 2 in these cells. Pretreatment of HK-2 cells with modulators of PKC- and Ca(2+)/calmodulin-mediated pathways (but not those that modulate PKA-, protein tyrosine kinase-, or nitric oxide-mediated pathways) led to significant alterations in biotin uptake. Maintaining the HK-2 cells in a biotin-deficient growth medium led to a marked upregulation in biotin transport, which was associated with an increase in hSMVT protein and RNA levels and an increase in activity of the hSMVT promoters. These results demonstrate that biotin uptake by human renal epithelial cells occurs via the hSMVT system and that the process is regulated by intracellular PKC- and Ca(2+)/calmodulin-mediated pathways. The uptake process appears to be adaptively regulated by extracellular biotin level, which involves transcriptional regulatory mechanism(s). PMID:15561972

  20. Predictors of Postoperative Finger Stiffness in Unstable Proximal Phalangeal Fractures

    PubMed Central

    Onishi, Tadanobu; Shimizu, Takamasa; Fujitani, Ryotaro; Shigematsu, Koji; Tanaka, Yasuhito

    2015-01-01

    Background: The purpose of this study was to determine the risk factors for postoperative finger stiffness after open reduction and internal fixation of unstable proximal phalangeal fractures using a low-profile plate and/or screw system. We hypothesized that dorsal plate placement is a risk factor for postoperative finger stiffness. Methods: Seventy consecutive patients (50 men, 20 women; average age, 40 years) with 75 unstable proximal phalangeal fractures were treated with titanium plates and/or screws and evaluated at a minimum follow-up of 1 year. Thirty-six comminuted fractures and 24 intra-articular fractures were included, and 16 fractures had associated soft-tissue injuries. Plate fixation was performed in 59 fractures, and the remaining 16 were fixed with screws only. The implants were placed in a dorsal location in 33 fractures and in a lateral or volar location in 42 fractures. Finger stiffness was defined as a total active range of finger motion <80% for the treated finger. Univariate and multivariate analyses were performed on 8 variables: patient characteristics (age and sex), fracture characteristics (fracture comminution, joint involvement, and associated soft-tissue injury), and surgical characteristics (type and location of implants and removal of the implants). Results: Postoperative finger stiffness occurred in 38 fractures. The multivariate analysis indicated that plate fixation (odds ratio, 5.9; 95% confidence interval, 1.5–24.0; P = 0.01) and dorsal placement (odds ratio, 3.0; 95% confidence interval, 1.1–8.3; P = 0.03) were independent risk factors for finger stiffness. Conclusion: We recommend the use of screw fixation as much as possible for unstable proximal phalangeal fractures using a midlateral approach.

  1. Efficiency of the Lausanne Clinical Pathway for Proximal Femoral Fractures

    PubMed Central

    Fleury, Nicole; Chevalley, François; Rubli, Eve; Coti, Pauline; Farron, Alain; Jolles, Brigitte M.

    2015-01-01

    Purpose/Introduction: The number of hip fractures is rising, due to increases in life expectancy. In such cases, patients are at risk from post-operative complications and subsequently the average length of hospitalization may be extended. In 2011, we established a clinical pathway (CP), a specific model of care for patient-care management, to improve the clinical and economic outcomes of proximal femoral fracture management in elderly patients. The goal was to evaluate the CP using clinical, process, and financial indicators. Methods: We included all surgical patients aged 65 and over, admitted to the emergency department with a fracture of the proximal femur following a fall. Assessment parameters included three performance indicators: clinical, process, and financial. The clinical indicators were the presence or absence of acute delirium on the third post-operative day, diagnosis of nosocomial pneumonia, and the number of patients fulfilling at least 75% of their nutritional requirements at the end of the hospitalization period. The process indicator was the time interval between arrival at the emergency department and surgery. The financial indicator was based on the number of days spent in hospital. Results: From 2011 to 2013, 669 patients were included in the CP. We observed that the average length of stay in hospital decreased as soon as the CP was implemented and stabilized afterwards. The goal of 90% of patients undergoing surgery within 48?h of arrival in the emergency department was surpassed in 2013 (93.1%). Furthermore, we observed an improvement in the clinical indicators. Conclusion: The application of a CP allowed an improvement in the qualitative and quantitative efficiency of proximal femoral fracture management in elderly patients, in terms of clinical, process, and financial factors. PMID:25745631

  2. Saccharomyces boulardii upgrades cellular adaptation after proximal enterectomy in rats

    PubMed Central

    Buts, J; De Keyser, N; Marandi, S; Hermans, D; Sokal, E; Chae, Y; Lambotte, L; Chanteux, H; Tulkens, P

    1999-01-01

    BACKGROUND—Saccharomyces boulardii is a non-pathogenic yeast which exerts trophic effects on human and rat small intestinal mucosa.?AIMS—To examine the effects of S boulardii on ileal adaptation after proximal enterectomy in rats.?METHODS—Wistar rats, aged eight weeks, underwent 60% proximal resection or transection and received by orogastric intubation either 1 mg/g body wt per day lyophilised S boulardii or the vehicle for seven days. The effects on ileal mucosal adaptation were assessed eight days after surgery.?RESULTS—Compared with transection, resection resulted in mucosal hyperplasia with significant decreases in the specific and total activities of sucrase, lactase, and maltase. Treatment of resected animals with S boulardii had no effect on mucosal hyperplasia but did upgrade disaccharidase activities to the levels of the transected group. Enzyme stimulation by S boulardii was associated with significant increases in diamine oxidase activity and mucosal polyamine concentrations. Likewise, sodium dependent D-glucose uptake by brush border membrane vesicles, measured as a function of time and glucose concentration in the incubation medium, was significantly (p<0.05) increased by 81% and three times respectively in the resected group treated with S boulardii. In agreement with this, expression of the sodium/glucose cotransporter-1 in brush border membranes of resected rats treated with S boulardii was enhanced twofold compared with resected controls.?CONCLUSION—Oral administration of S boulardii soon after proximal enterectomy improves functional adaptation of the remnant ileum.???Keywords: Saccharomyces boulardii; intestine; adaptation; polyamines; brush border membrane enzymes; glucose uptake PMID:10369710

  3. Neurons, potassium, and glia in proximal retina of Necturus.

    PubMed

    Karwoski, C J; Proenza, L M

    1980-02-01

    Light-evoked K+ flux and intracellular Müller (glial) cell and on/off-neuron responses were recorded from the proximal retina of Necturus in eyecups from which the vitreous was not drained. On/off-responses, probably arising from amacrine cells, showed an initial transient and a sustained component that always exhibited surround antagonism. Müller cell responses were small but otherwise similar to those recorded in eyecups drained of vitreous. The proximal K+ increase and Müller cell responses had identical decay times, and on some occasions the latency and rise time of the K+ increase nearly matched Müller cell responses, indicating that the recorded K+ responses were not always appreciably degraded by electrode "dead space." The spatiotemporal distribution of the K+ increase showed that both diffusion and active reuptake play important roles in K+ clearance. The relationship between on/off-neuron responses and the K+ increase was modelled by assuming that (a) K+ release is positively related to the instantaneous amplitude of the neural response, and (b) K+ accumulating in extracellular space is cleared via mechanisms with approximately exponential time-courses. These two processes were approximated by low-pass filtering the on/off-neuron responses, resulting in modelled responses that match the wave form and time-course of the K+ increase and behave quantitatively like the K+ increase to changes in stimulus intensity and diameter. Thus, on/off-neurons are probably a primary source of the proximal light-evoked K+ increase that depolarizes glial cells to generate the M-wave. PMID:6246191

  4. The impact of scanner model vectorization on optical proximity correction

    NASA Astrophysics Data System (ADS)

    Tyminski, Jacek K.; Nakashima, Tashiharu; Zhang, Qiaolin; Matsuyama, Tomoyuki; Lucas, Kevin

    2007-05-01

    Low pass filtering taking place in the projection tools used by IC industry leads to a range of optical proximity effects resulting in undesired IC characteristics. To correct these predicable OPEs, EDA industry developed various, model-based correction methodologies. Of course, the success of this mission is strongly dependent on how complete the imaging models are. To represent the image formation and to capture the OPEs, the EDA community adopted various models based on simplified representations of the projection tools. Resulting optical proximity correction models are capable of correcting OPEs driven by the fundamental imaging conditions such as wavelength, illuminator layout, reticle technology, and lens numerical aperture, to name a few. It is well known in the photolithography community that OPEs are dependent on the scanner characteristics. Therefore, to reach the level of accuracy required by the leading edge IC designs, photolithography simulation has to include systematic scanner fingerprint data. These tool fingerprints capture excursions of the imaging tools from the ideal imaging setup conditions. They quantify the performance of key projection tool components such as illuminator and lens signatures. To address the imaging accuracy requirements, the scanner engineering and the EDA communities developed OPC models capable of correcting for imaging tools engineering attributes captured by the imaging tools fingerprints. Deployment of immersion imaging systems has presented the photolithography community with new opportunities and challenges. These advanced scanners, designed to image in deep sub-wavelength regime, incorporate features invoking the optical phenomena previously unexplored in commercial scanners. Most notably, the state of the art scanners incorporate illuminators with high degree of polarization control and projection lenses with hyper-NAs. The image formation in these advanced projectors exploits a wide range of vectorial interactions originating at the illuminator, on the pattern mask, in the projection lens and at the wafer. The presence of these, previously subdued phenomena requires that the imaging simulation methodologies be refined, increasing the complexity of the OPE models and optical proximity correction methodologies.

  5. A simple method of intramedullary fixation for proximal interphalangeal arthrodesis.

    PubMed

    Canales, Michael B; Razzante, Mark C; Ehredt, Duane J; Clougherty, Coleman O

    2014-01-01

    Lesser digital arthrodesis has become one of the most widely used techniques in foot and ankle surgery. When performing digital arthrodesis, surgeons have an abundance of options for implantable devices. We provide information on a simple method of achieving successful arthrodesis. An intramedullary Kirschner wire is implanted into the proximal phalanx with the intermediate phalanx compressed over the wire for rigid internal fixation to avoid the use of an external device. We have had results similar to those from the published data of more expensive implants. PMID:24846156

  6. Nanofabrication of nanopattern and microdevices using contact/proximity lithography

    NASA Astrophysics Data System (ADS)

    Ting, Yung-Chiang; Shy, Shyi-Long; Lee, Ming-Chun; Dai, Bau-Tong

    2004-08-01

    The oldest lithography technique contact/proximity printing are widely used for research activity, most MEMS, Bio-Chip and Optical Electro devices can be fabricated by this method. In this paper, deep submicron 1x mask can be fabricated easily by using e-beam exposure, chemically amplified resist (CAR) and Cr dry etching, a chemical shrink method using dry/wet etching technology was proposed for nanofabrication by using Cr film as hard mask. Micro channel for biochip as well as micro lens for Optical Electro devices can easily be fabricated on glass and quartz substrates by this method.

  7. Machado-Joseph disease presenting as severe asymmetric proximal neuropathy

    PubMed Central

    van Schaik, I N; Jobsis, G; Vermeulen, M; Keizers, H; Bolhuis, P; de Visser, M

    1997-01-01

    Despite much effort, a 74 year old man with progressive proximal weakness and sensory disturbances due to axonal neuropathy remained a diagnostic problem. Investigation of his family disclosed an additional patient with a cerebellar syndrome and a family member with mainly pyramidal features. Analysis of DNA showed a CAG repeat expansion in the Machado-Joseph disease gene in all three patients. Although not conclusively proved, we think that the neuropathy of the index case is linked to the CAG repeat expansion. Machado-Joseph disease should be considered in progressive axonal neuropathy.?? PMID:9343141

  8. Localized pigmented villonodular synovitis of the proximal tibiofibular joint.

    PubMed

    Kwon, Jae Ho; Han, Jae Hwi; Almeida, Vivian Rd'; Kim, Seong Hyun; Park, Hai Jin; Nha, Kyung-Wook

    2014-12-01

    Pigmented villonodular synovitis (PVNS) is a rare disease. It is a benign neoplastic process typically affecting young to middle-aged adults and most commonly involving the knee, hip, and shoulder joints. The symptoms include diffuse pain and swelling with discomfort. We report a rare case of localized PVNS originating at the proximal tibiofibular joint in a 39-year-old female patient with radiologic changes for short duration of time. The clinical history, plain radiographs, magnetic resonance imaging, and pathologic findings of the reported patient were reviewed. Complete surgical excision was performed and there was no evidence of recurrence after one-year follow-up. PMID:25505708

  9. Distributed proximity sensor system having embedded light emitters and detectors

    NASA Technical Reports Server (NTRS)

    Lee, Sukhan (Inventor)

    1990-01-01

    A distributed proximity sensor system is provided with multiple photosensitive devices and light emitters embedded on the surface of a robot hand or other moving member in a geometric pattern. By distributing sensors and emitters capable of detecting distances and angles to points on the surface of an object from known points in the geometric pattern, information is obtained for achieving noncontacting shape and distance perception, i.e., for automatic determination of the object's shape, direction and distance, as well as the orientation of the object relative to the robot hand or other moving member.

  10. Ground plane insulating coating for proximity focused devices

    DOEpatents

    Power, G.D.

    1998-07-14

    A thin layer of alumina (aluminum oxide) is coated onto the ground plane of a microchannel plate (MCP) without covering the pores of the MCP so it does not effect the performance. The coating is sputtered onto the ground plane at a very steep angle. The addition of the thin dielectric coating of alumina greatly improves the spatial resolution of proximity focused image intensifiers using a narrow gap between the phosphor screen and the MCP. With the coating on the ground plane and the same gap the phosphor screen can be ran at 9000 volts, as compared to 3 kV without the coating. 3 figs.

  11. Ground plane insulating coating for proximity focused devices

    DOEpatents

    Power, Gary D. (Manteca, CA)

    1998-01-01

    A thin layer of alumina (aluminum oxide) is coated onto the ground plane of a microchannel plate (MCP) without covering the pores of the MCP so it does not effect the performance. The coating is sputtered onto the ground plane at a very steep angle. The addition of the thin dielectric coating of alumina greatly improves the spatial resolution of proximity focused image intensifiers using a narrow gap between the phosphor screen and the MCP. With the coating on the ground plane and the same gap the phosphor screen can be ran at 9000 volts, as compared to 3 kV without the coating.

  12. Diagnosis using the proximal and lateral nail folds.

    PubMed

    Chang, Patricia

    2015-04-01

    This article includes the etiology and pathophysiological data of each entity, classifying them as dermatologic, systemic, infectious, neoplastic, traumatic, and other classifications. The entities inherent to the periungual folds are also included, such as acute paronychia, chronic paronychia, retronychia, hangnails, hematomas of the proximal fold caused by oximeter, onychocryptosis, hypertrophy of the lateral folds, and infections caused by Candida albicans, Pseudomonas, and Staphylococcus aureus. Additionally, pathologies caused by diabetes mellitus, sepsis, endocarditis, drug reactions, and finally less frequent diseases that also affect the nail folds are discussed. PMID:25828713

  13. Cascading failures in networks with proximate dependent nodes.

    PubMed

    Kornbluth, Yosef; Lowinger, Steven; Cwilich, Gabriel; Buldyrev, Sergey V

    2014-03-01

    We study the mutual percolation of a system composed of two interdependent random regular networks. We introduce a notion of distance to explore the effects of the proximity of interdependent nodes on the cascade of failures after an initial attack. We find a nontrivial relation between the nature of the transition through which the networks disintegrate and the parameters of the system, which are the degree of the nodes and the maximum distance between interdependent nodes. We explain this relation by solving the problem analytically for the relevant set of cases. In the process, we solve a variant of Rényi's parking problem on treelike graphs. PMID:24730900

  14. Proximal microdeletions and microduplications of 1q21.1 contribute to variable abnormal phenotypes.

    PubMed

    Rosenfeld, Jill A; Traylor, Ryan N; Schaefer, G Bradley; McPherson, Elizabeth W; Ballif, Blake C; Klopocki, Eva; Mundlos, Stefan; Shaffer, Lisa G; Aylsworth, Arthur S

    2012-07-01

    Chromosomal band 1q21.1 can be divided into two distinct regions, proximal and distal, based on segmental duplications that mediate recurrent rearrangements. Microdeletions and microduplications of the distal region within 1q21.1, which are susceptibility factors for a variety of neurodevelopmental phenotypes, have been more extensively studied than proximal microdeletions and microduplications. Proximal microdeletions are known as a susceptibility factor for thrombocytopenia-absent radius (TAR) syndrome, but it is unclear if these proximal microdeletions have other phenotypic consequences. Therefore, to elucidate the clinical significance of rearrangements of the proximal 1q21.1 region, we evaluated the phenotypes in patients identified with 1q21.1 rearrangements after referral for clinical microarray testing. We report clinical information for 55 probands with copy number variations (CNVs) involving proximal 1q21.1: 22 microdeletions and 20 reciprocal microduplications limited to proximal 1q21.1 and 13 microdeletions that include both the proximal and distal regions. Six individuals with proximal microdeletions have TAR syndrome. Three individuals with proximal microdeletions and two individuals with larger microdeletions of proximal and distal 1q21.1 have a 'partial' TAR phenotype. Furthermore, one subject with TAR syndrome has a smaller, atypical deletion, narrowing the critical deletion region for the syndrome. Otherwise, phenotypic features varied among individuals with these microdeletions and microduplications. The recurrent, proximal 1q21.1 microduplications are enriched in our population undergoing genetic testing compared with control populations. Therefore, CNVs in proximal 1q21.1 can be a contributing factor for the development of abnormal phenotypes in some carriers. PMID:22317977

  15. Orion Handling Qualities During ISS Proximity Operations and Docking

    NASA Technical Reports Server (NTRS)

    Stephens, John-Paul; Vos, Gordon A.; Bilimoria, Karl D.; Mueller, Eric R.; Brazzel, Jack; Spehar, Pete

    2011-01-01

    NASA's Orion spacecraft is designed to autonomously rendezvous and dock with many vehicles including the International Space Station. However, the crew is able to assume manual control of the vehicle s attitude and flight path. In these instances, Orion must meet handling qualities requirements established by NASA. Two handling qualities assessments were conducted at the Johnson Space Center to evaluate preliminary designs of the vehicle using a six degree of freedom, high-fidelity guidance, navigation, and control simulation. The first assessed Orion s handling qualities during the last 20 ft before docking, and included both steady and oscillatory motions of the docking target. The second focused on manual acquisition of the docking axis during the proximity operations phase and subsequent station-keeping. Cooper-Harper handling qualities ratings, workload ratings and comments were provided by 10 evaluation pilots for the docking study and 5 evaluation pilots for the proximity operations study. For the docking task, both cases received 90% Level 1 (satisfactory) handling qualities ratings, exceeding NASA s requirement. All ratings for the ProxOps task were Level 1. These evaluations indicate that Orion is on course to meet NASA's handling quality requirements for ProxOps and docking.

  16. Redshifted 21cm Observations of High Redshift Quasar Proximity Zones

    E-print Network

    Stuart Wyithe

    2008-04-03

    The introduction of low-frequency radio arrays is expected to revolutionize the study of the reionization epoch. Observation of the contrast in redshifted 21cm emission between a large HII region and the surrounding neutral inter-galactic medium (IGM) will be the simplest and most easily interpreted signature. However the highest redshift quasars known are thought to reside in an ionized IGM. Using a semi-analytic model we describe the redshifted 21cm signal from the IGM surrounding quasars discovered using the i-drop out technique (i.e. quasars at z~6). We argue that while quasars at z<6.5 seem to reside in the post overlap IGM, they will still provide valuable probes of the late stages of the overlap era because the light-travel time across a quasar proximity zone should be comparable to the duration of overlap. For redshifted 21cm observations within a 32MHz bandpass, we find that the subtraction of a spectrally smooth foreground will not remove spectral features due to the proximity zone. These features could be used to measure the neutral hydrogen content of the IGM during the late stages of reionization. The density of quasars at z~6 is now well constrained. We use the measured quasar luminosity function to estimate the prospects for discovery of high redshift quasars in fields that will be observed by the Murchison Widefield Array.

  17. Cassini at Saturn Proximal Orbits - Attitude Control Challenges

    NASA Technical Reports Server (NTRS)

    Burk, Thomas A.

    2013-01-01

    The Cassini mission at Saturn will come to an end in the spring and summer of 2017 with a series of 22 orbits that will dip inside the rings of Saturn. These are called proximal orbits and will conclude with spacecraft disposal into the atmosphere of the ringed world on September 15, 2017. These unique orbits that cross the ring plane only a few thousand kilometers above the cloud tops of the planet present new attitude control challenges for the Cassini operations team. Crossing the ring plane so close to the inner edge of the rings means that the Cassini orientation during the crossing will be tailored to protect the sensitive electronics bus of the spacecraft. This orientation will put the sun sensors at some extra risk so this paper discusses how the team prepares for dust hazards. Periapsis is so close to the planet that spacecraft controllability with RCS thrusters needs to be evaluated because of the predicted atmospheric torque near closest approach to Saturn. Radiation during the ring plane crossings will likely trigger single event transients in some attitude control sensors. This paper discusses how the attitude control team deals with radiation hazards. The angular size and unique geometry of the rings and Saturn near periapsis means that star identification will be interrupted and this paper discusses how the safe mode attitude is selected to best deal with these large bright bodies during the proximal orbits.

  18. An acoustic proximity ranging system for monitoring the cavity thickness.

    PubMed

    Li, Xi; Wu, Renbiao; Rasmi, Srihari; Li, Jian; Cattafesta, Louis N; Sheplak, Mark

    2003-07-01

    To control high speed underwater vehicles, a proximity ranging system is needed to monitor the cavity thickness. In this paper, we study a time-of-flight (TOF) principle based acoustic proximity ranging system. By taking into account the acoustically hard boundary at the air-water interface, we first present a two-stage computationally efficient time delay estimation algorithm, referred to as the PEARS (Parameter Estimation for Acoustic Ranging Systems) algorithm, which is applicable to arbitrary transmitted waveforms. Numerical results based on a simulated waveform demonstrate that the PEARS estimates can approach the Cramér-Rao bound as the signal-to-noise ratio increases. We then present experiments performed by using commercially available acoustic transducers to further verify our method. To update TOF estimates quickly, a specially designed continuous wave (CW) is applied to the transducer. Experimental results show that PEARS can achieve high measurement accuracy for ranging distances less than 100 mm with an achievable parameter update rate of approximately 1.5 kHz. PMID:12894923

  19. Vision-based Proximity Detection in Retinal Surgery

    PubMed Central

    Richa, Rogério; Balicki, Marcin; Sznitman, Raphael; Meisner, Eric; Taylor, Russell; Hager, Gregory

    2012-01-01

    In retinal surgery, surgeons face difficulties such as indirect visualization of surgical targets, physiological tremor and lack of tactile feedback, which increase the risk of retinal damage caused by incorrect surgical gestures. In this context, intra-ocular proximity sensing has the potential to overcome current technical limitations and increase surgical safety. In this paper we present a system for detecting unintentional collisions between surgical tools and the retina using the visual feedback provided by the opthalmic stereo microscope. Using stereo images, proximity between surgical tools and the retinal surface can be detected when their relative stereo disparity is small. For this purpose, we developed a system comprised of two modules. The first is a module for tracking the surgical tool position on both stereo images. The second is a disparity tracking module for estimating a stereo disparity map of the retinal surface. Both modules were specially tailored for coping with the challenging visualization conditions in retinal surgery. The potential clinical value of the proposed method is demonstrated by extensive testing using a silicon phantom eye and recorded rabbit in vivo data. PMID:22692869

  20. Restoring proximal caries lesions conservatively with tunnel restorations.

    PubMed

    Chu, Chun-Hung; Mei, May L; Cheung, Chloe; Nalliah, Romesh P

    2013-01-01

    The tunnel restoration has been suggested as a conservative alternative to the conventional box preparation for treating proximal caries. The main advantage of tunnel restoration over the conventional box or slot preparation includes being more conservative and increasing tooth integrity and strength by preserving the marginal ridge. However, tunnel restoration is technique-sensitive and can be particularly challenging for inexperienced restorative dentists. Recent advances in technology, such as the contemporary design of dental handpieces with advanced light-emitting diode (LED) and handheld comfort, offer operative dentists better vision, illumination, and maneuverability. The use of magnifying loupes also enhances the visibility of the preparation. The advent of digital radiographic imaging has improved dental imaging and reduced radiation. The new generation of restorative materials has improved mechanical properties. Tunnel restoration can be an option to restore proximal caries if the dentist performs proper case selection and pays attention to the details of the restorative procedures. This paper describes the clinical technique of tunnel restoration and reviews the studies of tunnel restorations. PMID:24019754

  1. Unconventional proximity-induced superconductivity in bilayer systems

    NASA Astrophysics Data System (ADS)

    Parhizgar, Fariborz; Black-Schaffer, Annica M.

    2014-11-01

    We study the proximity-induced superconducting state in a general bilayer-conventional s -wave superconductor hybrid structure. For the bilayer we include a general parabolic dispersion, Rashba spin-orbit coupling, and finite-layer tunneling as well as the possibility to apply a bias potential and a magnetic Zeeman field, in order to address experimentally relevant bilayer systems, ranging from topological insulator thin films to generic double quantum well systems. By extracting the proximity-induced anomalous Green's function in the bilayer, we show a very rich structure for the superconducting pairing, including different spin states and odd-frequency pairing. Equal-spin spin-triplet (px±i py )-wave pairing is induced in both layers in the presence of a finite spin-orbit coupling and opposite-spin spin-triplet s -wave pairing with odd-frequency dependence appears for an applied magnetic Zeeman field. Finite interlayer pairing is also generally present in the bilayer. The interlayer pairing can be either even or odd in the layer index, with a complete reciprocity between parity in frequency and in layer index. We also find that a bilayer offers the possibility of sign reversal of the superconducting order parameters, both between the two layers and between multiple Fermi surfaces.

  2. Proximity to Pollution Sources and Risk of Amphibian Limb Malformation

    PubMed Central

    Taylor, Brynn; Skelly, David; Demarchis, Livia K.; Slade, Martin D.; Galusha, Deron; Rabinowitz, Peter M.

    2005-01-01

    The cause of limb deformities in wild amphibian populations remains unclear, even though the apparent increase in prevalence of this condition may have implications for human health. Few studies have simultaneously assessed the effect of multiple exposures on the risk of limb deformities. In a cross-sectional survey of 5,264 hylid and ranid metamorphs in 42 Vermont wetlands, we assessed independent risk factors for nontraumatic limb malformation. The rate of nontraumatic limb malformation varied by location from 0 to 10.2%. Analysis of a subsample did not demonstrate any evidence of infection with the parasite Ribeiroia. We used geographic information system (GIS) land-use/land-cover data to validate field observations of land use in the proximity of study wetlands. In a multiple logistic regression model that included land use as well as developmental stage, genus, and water-quality measures, proximity to agricultural land use was associated with an increased risk of limb malformation (odds ratio = 2.26; 95% confidence interval, 1.42–3.58; p < 0.001). The overall discriminant power of the statistical model was high (C = 0.79). These findings from one of the largest systematic surveys to date provide support for the role of chemical toxicants in the development of amphibian limb malformation and demonstrate the value of an epidemiologic approach to this problem. PMID:16263502

  3. Probing nuclear pore complex architecture with proximity-dependent biotinylation

    PubMed Central

    Kim, Dae In; KC, Birendra; Zhu, Wenhong; Motamedchaboki, Khatereh; Doye, Valérie; Roux, Kyle J.

    2014-01-01

    Proximity-dependent biotin identification (BioID) is a method for identifying protein associations that occur in vivo. By fusing a promiscuous biotin ligase to a protein of interest expressed in living cells, BioID permits the labeling of proximate proteins during a defined labeling period. In this study we used BioID to study the human nuclear pore complex (NPC), one of the largest macromolecular assemblies in eukaryotes. Anchored within the nuclear envelope, NPCs mediate the nucleocytoplasmic trafficking of numerous cellular components. We applied BioID to constituents of the Nup107–160 complex and the Nup93 complex, two conserved NPC subcomplexes. A strikingly different set of NPC constituents was detected depending on the position of these BioID-fusion proteins within the NPC. By applying BioID to several constituents located throughout the extremely stable Nup107–160 subcomplex, we refined our understanding of this highly conserved subcomplex, in part by demonstrating a direct interaction of Nup43 with Nup85. Furthermore, by using the extremely stable Nup107–160 structure as a molecular ruler, we defined the practical labeling radius of BioID. These studies further our understanding of human NPC organization and demonstrate that BioID is a valuable tool for exploring the constituency and organization of large protein assemblies in living cells. PMID:24927568

  4. Proximity effect in superconductor/conical magnet/ferromagnet heterostructures

    NASA Astrophysics Data System (ADS)

    Annett, James; Fritsch, Daniel

    2014-03-01

    At the interface between a superconductor and a ferromagnetic metal spin-singlet Cooper pairs can penetrate into the ferromagnetic part of the heterostructure with an oscillating and decaying spin-singlet Cooper pair density. However, if the interface allows for a spin-mixing effect, equal-spin spin-triplet Cooper pairs can be generated that can penetrate much further into the ferromagnetic part of the heterostructure, known as the long-range proximity effect. Here, we present results of spin-mixing based on self-consistent solutions of the microscopic Bogoliubov-de Gennes equations incorporating a tight-binding model. In particular, we include a conical magnet into our model heterostructure to generate the spin-triplet Cooper pairs and analyze the influence of conical and ferromagnetic layer thickness on the unequal-spin and equal-spin spin-triplet pairing correlations. It will be shown that, in agreement with experimental observations, a minimum thickness of the conical magnet is necessary to generate a sufficient amount of equal-spin spin-triplet Cooper pairs allowing for the long-range proximity effect. This work has been financially supported by the EPSRC (EP/I037598/1).

  5. Proximity effect in superconductor/conical magnet/ferromagnet heterostructures

    NASA Astrophysics Data System (ADS)

    Fritsch, Daniel; Annett, James F.

    2014-05-01

    At the interface between a superconductor and a ferromagnetic metal spin-singlet Cooper pairs can penetrate into the ferromagnetic part of the heterostructure with an oscillating and decaying spin-singlet Cooper pair density. However, if the interface allows for a spin-mixing effect, equal-spin spin-triplet Cooper pairs can be generated that can penetrate much further into the ferromagnetic part of the heterostructure, known as the long-range proximity effect. Here, we present results of spin-mixing based on self-consistent solutions of the microscopic Bogoliubov-de Gennes equations in the clean limit incorporating a tight-binding model. In particular, we include a conical magnet into our model heterostructure to generate the spin-triplet Cooper pairs and analyse the influence of conical and ferromagnetic layer thickness on the unequal-spin and equal-spin spin-triplet pairing correlations. It will be shown that, in agreement with experimental observations, a minimum thickness of the conical magnet is necessary to generate a sufficient amount of equal-spin spin-triplet Cooper pairs allowing for the long-range proximity effect.

  6. Optimal proximity correction: application for flash memory design

    NASA Astrophysics Data System (ADS)

    Chen, Y. O.; Huang, D. L.; Sung, K. T.; Chiang, J. J.; Yu, M.; Teng, F.; Chu, Lung; Rey, Juan C.; Bernard, Douglas A.; Li, Jiangwei; Li, Junling; Moroz, V.; Boksha, Victor V.

    1998-06-01

    Proximity Correction is the technology for which the most of IC manufacturers are committed already. The final intended result of correction is affected by many factors other than the optical characteristics of the mask-stepper system, such as photoresist exposure, post-exposure bake and development parameters, etch selectivity and anisotropy, and underlying topography. The most advanced industry and research groups already reported immediate need to consider wafer topography as one of the major components during a Proximity Correction procedure. In the present work we are discussing the corners rounding effect (which eventually cause electrical leakage) observed for the elements of Poly2 layer for a Flash Memory Design. It was found that the rounding originated by three- dimensional effects due to variation of photoresist thickness resulting from the non-planar substrate. Our major goal was to understand the reasons and correct corner rounding. As a result of this work highly effective layout correction methodology was demonstrated and manufacturable Depth Of Focus was achieved. Another purpose of the work was to demonstrate complete integration flow for a Flash Memory Design based on photolithography; deposition/etch; ion implantation/oxidation/diffusion; and device simulators.

  7. The effect of proximity on landmark use in Clark's nutcrackers.

    PubMed

    Gould-Beierle; Kamil

    1999-09-01

    Clark's nutcrackers, Nucifraga columbiana, store thousands of pine seeds during the autumn and retrieve them throughout the winter. It has been shown that these birds are able to use visual cues to relocate hidden food in the laboratory. In this set of experiments, we trained three groups of Clark's nutcrackers to find a hidden food goal that was placed in the same spatial location relative to the testing room. During training, the location of two local cues in relation to the goal differed between the three groups. Group 1 learned the task with the cues closest to the goal, group 2 with the cues further from the goal, and group 3 with the cues furthest from the goal. To test whether the proximity of these two local cues to the goal affected how spatial information was used, we manipulated local and global information in a series of experiments. Results indicated that local cues were more important sources of spatial information for group 1, whereas global cues seemed to be used more by birds in groups 2 and 3. These findings suggest that the proximity of visual cues lead to overshadowing of other sources of spatial information surrounding the goal. Copyright 1999 The Association for the Study of Animal Behaviour. PMID:10479363

  8. Increased Expression of Rififylin in A?Proximal Tubules

    PubMed Central

    Gopalakrishnan, Kathirvel; Kumarasamy, Sivarajan; Yan, Yanling; Liu, Jiang; Kalinoski, Andrea; Kothandapani, Anbarasi; Farms, Phyllis; Joe, Bina

    2012-01-01

    Cell surface proteins are internalized into the cell through endocytosis and either degraded within lysosomes or recycled back to the plasma membrane. While perturbations in endosomal internalization are known to modulate renal function, it is not known whether similar alterations in recycling affect renal function. Rififylin is a known regulator of endocytic recycling with E3 ubiquitin protein ligase activity. In this study, using two genetically similar strains, the Dahl Salt-sensitive rat and an S.LEW congenic strain, which had allelic variants within a?Na+K+ATPase were increased in the proximal tubules from the congenic strain. Because rififylin does not directly regulate endocytosis and it is also a differentially expressed gene within the congenic segment, we reasoned that the observed alterations in the transcriptome of the congenic strain constitute a feedback response to the primary functional alteration of recycling caused by rififylin. To test this, recycling of transferrin was studied in isolated proximal tubules. Recycling was significantly delayed within isolated proximal tubules of the congenic strain, which also had a higher level of polyubiquitinated proteins and proteinuria compared with S. These data provide evidence to suggest that delayed endosomal recycling caused by excess of rififylin indirectly affects endocytosis, enhances intracellular protein polyubiquitination and contributes to proteinuria. PMID:22891072

  9. Implantation profile of 22Na continuous energy spectrum positrons in silicon

    Microsoft Academic Search

    P. J. Foster; P. Mascher; A. P. Knights; P. G. Coleman

    2007-01-01

    The implantation profile of positrons emitted from a continuous energy spectrum source of 22Na in close proximity to a silicon target is modeled. The primary motivation is the use of positron lifetime spectroscopy to characterize layers of defects such as those created by ion irradiation, usually deemed accessible only to techniques which utilize slow positrons. The model combines the Makhov

  10. Large-scale phosphoproteomic analysis of membrane proteins in renal proximal and distal tubule

    PubMed Central

    Feric, Marina; Zhao, Boyang; Hoffert, Jason D.; Pisitkun, Trairak

    2011-01-01

    Recent advances in mass spectrometry (MS) have provided means for large-scale phosphoproteomic profiling of specific tissues. Here, we report results from large-scale tandem MS [liquid chromatography (LC)-MS/MS]-based phosphoproteomic profiling of biochemically isolated membranes from the renal cortex, with focus on transporters and regulatory proteins. Data sets were filtered (by target-decoy analysis) to limit false-positive identifications to <2%. A total of 7,125 unique nonphosphorylated and 743 unique phosphorylated peptides were identified. Among the phosphopeptides identified were sites on transporter proteins, i.e., solute carrier (Slc, n = 63), ATP-binding cassette (Abc, n = 4), and aquaporin (Aqp, n = 3) family proteins. Database searches reveal that a majority of the phosphorylation sites identified in transporter proteins were previously unreported. Most of the Slc family proteins are apical or basolateral transporters expressed in proximal tubule cells, including proteins known to mediate transport of glucose, amino acids, organic ions, and inorganic ions. In addition, we identified potentially important phosphorylation sites for transport proteins from distal nephron segments, including the bumetanide-sensitive Na-K-2Cl cotransporter (Slc12a1 or NKCC2) at Ser87, Thr101, and Ser126 and the thiazide-sensitive Na-Cl cotransporter (Slc12a3 or NCC) at Ser71 and Ser124. A subset of phosphorylation sites in regulatory proteins coincided with known functional motifs, suggesting specific regulatory roles. An online database from this study (http://dir.nhlbi.nih.gov/papers/lkem/rcmpd/) provides a resource for future studies of transporter regulation. PMID:21209370

  11. Sub-micrometer resolution proximity X-ray microscope with digital image registration

    NASA Astrophysics Data System (ADS)

    Chkhalo, N. I.; Pestov, A. E.; Salashchenko, N. N.; Sherbakov, A. V.; Skorokhodov, E. V.; Svechnikov, M. V.

    2015-06-01

    A compact laboratory proximity soft X-ray microscope providing submicrometer spatial resolution and digital image registration is described. The microscope consists of a laser-plasma soft X-ray radiation source, a Schwarzschild objective to illuminate the test sample, and a two-coordinate detector for image registration. Radiation, which passes through the sample under study, generates an absorption image on the front surface of the detector. Optical ceramic YAG:Ce was used to convert the X-rays into visible light. An image was transferred from the scintillator to a charge-coupled device camera with a Mitutoyo Plan Apo series lens. The detector's design allows the use of lenses with numerical apertures of NA = 0.14, 0.28, and 0.55 without changing the dimensions and arrangement of the elements of the device. This design allows one to change the magnification, spatial resolution, and field of view of the X-ray microscope. A spatial resolution better than 0.7 ?m and an energy conversion efficiency of the X-ray radiation with a wavelength of 13.5 nm into visible light collected by the detector of 7.2% were achieved with the largest aperture lens.

  12. Proximate and elemental analysis of five selected medicinal plants of family Solanaceae.

    PubMed

    Hameed, Ishfaq; Hussain, Farrukh

    2015-07-01

    The proximate analysis revealed the presence of ash, moisture, protein, fiber, fats and carbohydrate. ANOVA showed that ash and moisture contents was non significant between the plant parts and phenological stages. Crude protein was non significant between the plant parts and phenological stages except for Datura innoxia parts but not for its phenolgical stages, while crude fats were non significant between the plant parts and phenological stages except for Solanum nigrum and Solanum surattense parts but not for their phenolgical stages. Crude fiber was non significant between the plant parts and phenological stages except for Datura innoxia parts but not for its phenolgical stages. And carbohydrates was non significant between the plant parts and phenological stages except for the phenolgical stages of Solanum surattense and Withania coagulans. The mineral analysis showed the presence of Cr, Zn, Cu, Mn, Fe, Ca, K, Mg and Na in the roots, stems, leaves, flowers and fruits of the plants in three different phenological stages. Only the micro-minerals were present in traces while the macro-minerals were present high quantities as compared to the micro-minerals. PMID:26142511

  13. Long-Term Results after Proximal Thoracic Aortic Redo Surgery

    PubMed Central

    Czerny, Martin; Barchichat, Ilan; Meszaros, Katharina; Sodeck, Gottfried H.; Weber, Alberto; Reineke, David; Englberger, Lars; Schönhoff, Florian; Kadner, Alexander; Jenni, Hansjörg; Schmidli, Jürg; Carrel, Thierry P.

    2013-01-01

    Objective To evaluate early and mid-term results in patients undergoing proximal thoracic aortic redo surgery. Methods We analyzed 60 patients (median age 60 years, median logistic EuroSCORE 40) who underwent proximal thoracic aortic redo surgery between January 2005 and April 2012. Outcome and risk factors were analyzed. Results In hospital mortality was 13%, perioperative neurologic injury was 7%. Fifty percent of patients underwent redo surgery in an urgent or emergency setting. In 65%, partial or total arch replacement with or without conventional or frozen elephant trunk extension was performed. The preoperative logistic EuroSCORE I confirmed to be a reliable predictor of adverse outcome- (ROC 0.786, 95%CI 0.64–0.93) as did the new EuroSCORE II model: ROC 0.882 95%CI 0.78–0.98. Extensive individual logistic EuroSCORE I levels more than 67 showed an OR of 7.01, 95%CI 1.43–34.27. A EuroSCORE II larger than 28 showed an OR of 4.44 (95%CI 1.4–14.06). Multivariate logistic regression analysis identified a critical preoperative state (OR 7.96, 95%CI 1.51–38.79) but not advanced age (OR 2.46, 95%CI 0.48–12.66) as the strongest independent predictor of in-hospital mortality. Median follow-up was 23 months (1–52 months). One year and five year actuarial survival rates were 83% and 69% respectively. Freedom from reoperation during follow-up was 100%. Conclusions Despite a substantial early attrition rate in patients presenting with a critical preoperative state, proximal thoracic aortic redo surgery provides excellent early and mid-term results. Higher EuroSCORE I and II levels and a critical preoperative state but not advanced age are independent predictors of in-hospital mortality. As a consequence, age alone should no longer be regarded as a contraindication for surgical treatment in this particular group of patients. PMID:23469220

  14. The oblique proximal phalangeal osteotomy in the correction of hallux valgus

    Microsoft Academic Search

    Michael M Cohen

    2003-01-01

    An oblique proximal phalangeal osteotomy is introduced as an alternative to the Akin procedure for the treatment of hallux valgus. It consists of a single oblique osteotomy directed from proximal-dorsal to plantar-distal. A retrospective review of 32 patients who underwent 36 oblique proximal osteotomies is presented. The mean follow-up was 11 months (range, 3 to 21 months). Pre- and postoperative

  15. Proximal Sensor Data from Routine Dual-Sensor Esophageal pH Monitoring Is Often Inaccurate

    Microsoft Academic Search

    Matt McCollough; Abdul Jabbar; Robert Cacchione; Jeff W. Allen; Steve Harrell; John M. Wo

    2004-01-01

    Dual-sensor esophageal pH monitoring is routinely used to diagnose GERD. However, the proximal sensor may not be in proximal esophagus in patients with shortened esophagi. Our objective was to determine how often the proximal sensor was misplaced and to determine the effect on pH monitoring. Superior margins of the upper and lower esophageal sphincters (UES and LES) were determined prospectively

  16. Treatment of proximal plantar fasciitis with ultrasound-guided steroid injection

    Microsoft Academic Search

    Wen-Chung Tsai; Chung-Li Wang; Fuk-Tan Tang; Tsz-Ching Hsu; Kuang-Hung Hsu; May-Kuen Wong

    2000-01-01

    Tsai W-C, Wang C-L, Tang F-T, Hsu T-C, Hsu K-H, Wong M-K. Treatment of proximal plantar fasciitis with ultrasound-guided steroid injection. Arch Phys Med Rehabil 2000;81:1416-21. Objective: To investigate the efficacy of ultrasound-guided steroid injection for the treatment of proximal plantar fasciitis and to evaluate mechanical properties of the heel pad after steroid injection. Design: Proximal plantar fascia and heel

  17. Bone mineral density in patients with cervical and trochanteric fractures of the proximal femur

    Microsoft Academic Search

    E. Vega; C. Mautalen; H. Gómez; A. Garrido; L. Melo; A. O. Sahores

    1991-01-01

    The bone mineral density (BMD) of the proximal femur, spine and radius shaft was determined in 75 women with atraumatic fractures of the proximal femur (FXf) (average age: 70.1±9.6 years) and 51 controls of similar age. Fractures were classified as either cervical (n=36) or trochanteric (n=39) on the basis of radiographic and surgical finding. The BMD of spine and proximal

  18. Proteomic profiling of the effect of metabolic acidosis on the apical membrane of the proximal convoluted tubule

    PubMed Central

    Walmsley, Scott J.; Freund, Dana M.

    2012-01-01

    The physiological response to the onset of metabolic acidosis requires pronounced changes in renal gene expression. Adaptations within the proximal convoluted tubule support the increased extraction of plasma glutamine and the increased synthesis and transport of glucose and of NH4+ and HCO3? ions. Many of these adaptations involve proteins associated with the apical membrane. To quantify the temporal changes in these proteins, proteomic profiling was performed using brush-border membrane vesicles isolated from proximal convoluted tubules (BBMVPCT) that were purified from normal and acidotic rats. This preparation is essentially free of contaminating apical membranes from other renal cortical cells. The analysis identified 298 proteins, 26% of which contained one or more transmembrane domains. Spectral counts were used to assess changes in protein abundance. The onset of acidosis produced a twofold, but transient, increase in the Na+-dependent glucose transporter and a more gradual, but sustained, increase (3-fold) in the Na+-dependent lactate transporter. These changes were associated with the loss of glycolytic and gluconeogenic enzymes that are contained in the BBMVPCT isolated from normal rats. In addition, the levels of ?-glutamyltranspeptidase increased twofold, while transporters that participate in the uptake of neutral amino acids, including glutamine, were decreased. These changes could facilitate the deamidation of glutamine within the tubular lumen. Finally, pronounced increases were also observed in the levels of DAB2 (3-fold) and myosin 9 (7-fold), proteins that may participate in endocytosis of apical membrane proteins. Western blot analysis and accurate mass and time analyses were used to validate the spectral counting. PMID:22357915

  19. Proximal and point detection of contaminated surfaces using Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Guicheteau, Jason A.; Christesen, Steven D.; Tripathi, Ashish; Emmons, Erik D.; Wilcox, Phillip G.; Emge, Darren K.; Pardoe, Ian J.; Fountain, Augustus W., III

    2011-11-01

    We are actively investigating the use of Raman spectroscopy for proximal standoff detection of chemicals and explosive materials on surfaces. These studies include Raman Chemical Imaging of contaminated fingerprints for forensic attribution and the assessments of commercial handheld or portable Raman instruments operating with near-infrared (IR) as well as ultraviolet (UV) laser excitation specifically developed for on-the-move reconnaissance of chemical contamination. As part of these efforts, we have measured the Raman cross sections of chemical agents, toxic industrial chemicals, and explosives from the UV to NIR. We have also measured and modeled the effect interrogation angle has on the Raman return from droplets on man-made surfaces. Realistic droplet distributions have been modeled and tested against variations in surface scan patterns and laser spot size for determining the optimum scan characteristics for detection of relevant surface contamination.

  20. Granger causality stock market networks: Temporal proximity and preferential attachment

    NASA Astrophysics Data System (ADS)

    Výrost, Tomáš; Lyócsa, Štefan; Baumöhl, Eduard

    2015-06-01

    The structure of return spillovers is examined by constructing Granger causality networks using daily closing prices of 20 developed markets from 2nd January 2006 to 31st December 2013. The data is properly aligned to take into account non-synchronous trading effects. The study of the resulting networks of over 94 sub-samples revealed three significant findings. First, after the recent financial crisis the impact of the US stock market has declined. Second, spatial probit models confirmed the role of the temporal proximity between market closing times for return spillovers, i.e. the time distance between national stock markets matters. Third, a preferential attachment between stock markets exists, i.e. the probability of the presence of spillover effects between any given two markets increases with their degree of connectedness to others.

  1. Residential Proximity to Environmental Hazards and Adverse Health Outcomes

    PubMed Central

    Maantay, Juliana A.; Chakraborty, Jayajit

    2011-01-01

    How living near environmental hazards contributes to poorer health and disproportionate health outcomes is an ongoing concern. We conducted a substantive review and critique of the literature regarding residential proximity to environmental hazards and adverse pregnancy outcomes, childhood cancer, cardiovascular and respiratory illnesses, end-stage renal disease, and diabetes. Several studies have found that living near hazardous wastes sites, industrial sites, cropland with pesticide applications, highly trafficked roads, nuclear power plants, and gas stations or repair shops is related to an increased risk of adverse health outcomes. Government agencies should consider these findings in establishing rules and permitting and enforcement procedures to reduce pollution from environmentally burdensome facilities and land uses. PMID:22028451

  2. Inversin relays Frizzled-8 signals to promote proximal pronephros development

    PubMed Central

    Lienkamp, Soeren; Ganner, Athina; Boehlke, Christopher; Schmidt, Thorsten; Arnold, Sebastian J.; Schäfer, Tobias; Romaker, Daniel; Schuler, Julia; Hoff, Sylvia; Powelske, Christian; Eifler, Annekathrin; Krönig, Corinna; Bullerkotte, Axel; Nitschke, Roland; Kuehn, E. Wolfgang; Kim, Emily; Burkhardt, Hans; Brox, Thomas; Ronneberger, Olaf; Gloy, Joachim; Walz, Gerd

    2010-01-01

    Mutations of inversin cause type II nephronophthisis, an infantile autosomal recessive disease characterized by cystic kidney disease and developmental defects. Inversin regulates Wnt signaling and is required for convergent extension movements during early embryogenesis. We now show that Inversin is essential for Xenopus pronephros formation, involving two distinct and opposing forms of cell movements. Knockdown of Inversin abrogated both proximal pronephros extension and distal tubule differentiation, phenotypes similar to that of Xenopus deficient in Frizzled-8. Exogenous Inversin rescued the pronephric defects caused by lack of Frizzled-8, indicating that Inversin acts downstream of Frizzled-8 in pronephros morphogenesis. Depletion of Inversin prevents the recruitment of Dishevelled in response to Frizzled-8 and impeded the accumulation of Dishevelled at the apical membrane of tubular epithelial cells in vivo. Thus, defective tubule morphogenesis seems to contribute to the renal pathology observed in patients with nephronophthisis type II. PMID:21059920

  3. Nutritive content of college meals. Proximate composition and vitamins.

    PubMed

    Walker, M A; Page, L

    1975-02-01

    Two samples, each consisting of menus of two breakfasts, lunches, and dinners, as offered to college students, were collected for seven consecutive days from each of fifty colleges. The composited meals were analyzed to determine proximate composition and content of vitamin A, vitamin D, thiamin, riboflavin, niacin, folacin, vitamin B6, and vitamin B12. On a per-person-per-day basis, the meals met or exceeded the Recommended Dietary Allowances for nineteen-to-twenty-two-year-old men and women for protein, vitamin A, riboflavin, and niacin. About a third of the meals were below the allowances for vitamin D, three-fifths were short in thiamin, and three-fourths were short in folacin and vitamin B6. A number of colleges offered meals that were short on calories. PMID:1112954

  4. Proximal airway pressure monitoring in the neonatal ICU.

    PubMed

    Mayock, D E; Tremblay, L

    1984-08-01

    The static and dynamic responses of diaphragm-type pressure manometers currently used with manual ventilation in the neonatal ICU were determined at different pressures and frequencies. Using a precalibrated transducer attached to a closed-loop system, the manometer peak pressure was adjusted to 15, 20, 25, and 30 cm H2O, first for static measurements and then again while the frequency was increased from 20 to 200 breath/min in increments of 20. Most manometers with inlet flow-restricting devices built into the manometer or attached to the connection system in a ventilator significantly underestimated the delivered pressure as the peak inflation pressure and frequency were increased. In those manometers without inlet flow restrictors the correlation between transducer pressure and observed manometer pressure was close. Diaphragm-type pressure manometers with inlet flow-restricting devices may substantially underestimate the delivered proximal airway pressure when incorporated into neonatal manual ventilation equipment. PMID:6589117

  5. Raman scattering as a probe of the superconducting proximity effect

    NASA Astrophysics Data System (ADS)

    Greene, L. H.; Dorsten, J. F.; Roshchin, I. V.; Abeyta, A. C.; Tanzer, T. A.; Kuchler, G.; Feldmann, W. L.; Bohn, P. W.

    1996-06-01

    Temperature-dependent Raman spectroscopy is used to investigate the effect of superconductivity on the near-surface electronic structure of a semiconductor in good electrical contact with a superconductor. The light scattering is performed through a high-quality thin (60-100Å) film of Nb, grown directly onto in-situ Ar+-etched (100)-n+InAs. Below Tc, the LO mode, associated with the surface charge accumulation layer in the InAs, is enhanced by ˜40% in comparison with the nearby L_bulk phonon mode. This change, reversible upon temperature cycling, is observed only when the Nb is in good electrical contact with the InAs. Preliminary results show a similar effect on NbN/InAs. Our results constitute the first optical detection of the superconducting proximity effect.

  6. Ultrasensitive proximity Josephson sensor with kinetic inductance readout

    NASA Astrophysics Data System (ADS)

    Giazotto, Francesco; Heikkilä, Tero T.; Pepe, Giovanni Piero; Helistö, Panu; Luukanen, Arttu; Pekola, Jukka P.

    2008-04-01

    We propose a mesoscopic kinetic-inductance radiation detector based on a long superconductor-normal metal-superconductor Josephson junction. The operation of this proximity Josephson sensor relies on large kinetic inductance variations under irradiation due to the exponential temperature dependence of the critical current. Coupled with a dc superconducting quantum interference device readout, the PJS is able to provide a signal to noise (S/N) ratio up to ˜103 in the terahertz regime if operated as calorimeter, while electrical noise equivalent power as low as ˜7×10-20W/?Hz at 200mK can be achieved in the bolometer operation. The high performance together with the ease of fabrication make this structure attractive as an ultrasensitive cryogenic detector of terahertz electromagnetic radiation.

  7. Transition Metal Dichalcogenide Growth via Close Proximity Precursor Supply

    PubMed Central

    O'Brien, Maria; McEvoy, Niall; Hallam, Toby; Kim, Hye-Young; Berner, Nina C.; Hanlon, Damien; Lee, Kangho; Coleman, Jonathan N.; Duesberg, Georg S.

    2014-01-01

    Reliable chemical vapour deposition (CVD) of transition metal dichalcogenides (TMDs) is currently a highly pressing research field, as numerous potential applications rely on the production of high quality films on a macroscopic scale. Here, we show the use of liquid phase exfoliated nanosheets and patterned sputter deposited layers as solid precursors for chemical vapour deposition. TMD monolayers were realized using a close proximity precursor supply in a CVD microreactor setup. A model describing the growth mechanism, which is capable of producing TMD monolayers on arbitrary substrates, is presented. Raman spectroscopy, photoluminescence, X-ray photoelectron spectroscopy, atomic force microscopy, transmission electron microscopy, scanning electron microscopy and electrical transport measurements reveal the high quality of the TMD samples produced. Furthermore, through patterning of the precursor supply, we achieve patterned growth of monolayer TMDs in defined locations, which could be adapted for the facile production of electronic device components. PMID:25487822

  8. Visualizing cell proximity with genetically encoded bioluminescent reporters.

    PubMed

    Jones, Krysten A; Li, David J; Hui, Elliot; Sellmyer, Mark A; Prescher, Jennifer A

    2015-04-17

    Cell-cell interactions underlie diverse physiological processes ranging from immune function to cell migration. Dysregulated cellular crosstalk also potentiates numerous pathologies, including infections and metastases. Despite their ubiquity in organismal biology, cell-cell interactions are difficult to examine in tissues and whole animals without invasive procedures. Here, we report a strategy to noninvasively image cell proximity using engineered bioluminescent probes. These tools comprise "split" fragments of Gaussia luciferase (Gluc) fused to the leucine zipper domains of Fos and Jun. When cells secreting the fragments draw near one another, Fos and Jun drive the assembly of functional, light-emitting Gluc. Photon production thus provides a readout on the distance between two cell types. We used the split fragments to visualize cell-cell interactions over time in vitro and in macroscopic models of cell migration. Further application of these tools in live organisms will refine our understanding of cell contacts relevant to basic biology and disease. PMID:25643167

  9. Variable reluctance proximity sensors for cryogenic valve position indication

    NASA Technical Reports Server (NTRS)

    Cloyd, R. A.

    1982-01-01

    A test was conducted to determine the performance of a variable reluctance proximity sensor system when installed in a space shuttle external tank vent/relief valve. The sensors were used as position indicators. The valve and sensors were cycled through a series of thermal transients; while the valve was being opened and closed pneumatically, the sensor's performance was being monitored. During these thermal transients, the vent valve was cooled ten times by liquid nitrogen and two times by liquid hydrogen. It was concluded that the sensors were acceptable replacements for the existing mechanical switches. However, the sensors need a mechanical override for the target similar to what is presently used with the mechanical switches. This override could insure contact between sensor and target and eliminate any problems of actuation gap growth caused by thermal gradients.

  10. Factors affecting minority population proximity to hazardous facilities

    SciTech Connect

    Nieves, L.A. [Argonne National Lab., IL (United States); Nieves, A.L. [Wheaton Coll., IL (United States)]|[Argonne National Lab., IL (United States)

    1995-04-01

    Disproportionate exposure of minority groups to environmental hazards has been attributed to ``environmental racism`` by some authors, without systematic investigation of the factors underlying this exposure pattern. This study examines regional differences in the proximity of African-Americans, Hispanics, Asians, and non-Hispanic Whites to a broad range of facility types and explores the effects of urban and income factors. A statistically significant inverse relationship is found between the percentage of non-Hispanic Whites and virtually all facility categories in all regions. Except for Hispanics in the South, all such associations for minority groups show a direct relationship, though some are nonsignificant. The geographic concentration of facilities is more closely tied to urbanization than to economic factors. Controlling for both urban and economic factors, minority population concentration is still a significant explanatory variable for some facility types in some regions. This finding is most consistent for African-Americans.

  11. Material dependence of Casimir forces: Gradient expansion beyond proximity

    NASA Astrophysics Data System (ADS)

    Bimonte, Giuseppe; Emig, Thorsten; Kardar, Mehran

    2012-02-01

    A widely used method for estimating Casimir interactions [H. B. G. Casimir, Proc. K. Ned. Akad. Wet. 51, 793 (1948)] between gently curved material surfaces at short distances is the proximity force approximation (PFA). While this approximation is asymptotically exact at vanishing separations, quantifying corrections to PFA has been notoriously difficult. Here, we use a derivative expansion to compute the leading curvature correction to PFA for metals (gold) at room temperature. We derive an explicit expression for the amplitude ??1 of the PFA correction to the force gradient for axially symmetric surfaces. In the non-retarded limit, the corrections to the Casimir free energy are found to scale logarithmically with distance. For gold, ??1 has an unusually large temperature dependence.

  12. Potassium depletion increases luminal Na+/H+ exchange and basolateral Na+:CO3=:HCO3- cotransport in rat renal cortex.

    PubMed Central

    Soleimani, M; Bergman, J A; Hosford, M A; McKinney, T D

    1990-01-01

    Most HCO3- reabsorption in proximal tubules occurs via electroneutral Na+/H+ exchange in brush border membranes (BBMS) and electrogenic Na+:CO3=:HCO3- cotransport in basolateral membranes (BLMS). Since potassium depletion (KD) increases HCO3- reabsorption in proximal tubules, we evaluated these transport systems using BBM and BLM vesicles, respectively, from control (C) and KD rats. Feeding rats a potassium deficient diet for 3-4 wk resulted in lower plasma [K+] (2.94 mEq/liter, KD vs. 4.47 C), and higher arterial pH (7.51 KD vs. 7.39 C). KD rats gained less weight than C but had higher renal cortical weight. Influx of 1 mM 22Na+ at 5 s (pHo 7.5, pHi 6.0, 10% CO2, 90% N2) into BLM vesicles was 44% higher in the KD group compared to C with no difference in equilibrium uptake. The increment in Na+ influx in the KD group was DIDS sensitive, suggesting that Na+:CO3=:HCO3- cotransport accounted for the observed differences. Kinetic analysis of Na+ influx showed a Km of 8.2 mM in KD vs. 7.6 mM in C and Vmax of 278 nmol/min/mg protein in KD vs. 177 nmol/min/mg protein in C. Influx of 1 mM 22Na+ at 5 s (pHo 7.5, pHi 6.0) into BBM vesicles was 34% higher in the KD group compared to C with no difference in equilibrium uptake. The increment in Na+ influx in the KD group was amiloride sensitive, suggesting that Na+/H+ exchange was responsible for the observed differences. Kinetic analysis of Na+ influx showed a Km of 6.2 mM in KD vs. 7.1 mM in C and Vmax of 209 nmol/min/mg protein in KD vs. 144 nmol/min/mg protein in C. Uptakes of Na(+)-dependent [3H]glucose into BBM and [14C]succinate into BLM vesicles were not different in KD and C groups, suggesting that the Na+/H+ exchanger and Na+:CO3=:HCO3- cotransporter activities were specifically altered in KD. We conclude that adaptive increases in basolateral Na+:CO3=:HCO3- cotransport and luminal Na+H+ exchange are likely responsible for increased HCO3- reabsorption in proximal tubules of KD animals. Images PMID:2170445

  13. Treatment of proximal humerus fractures in the elderly.

    PubMed

    Launonen, Antti P; Lepola, Vesa; Flinkkilä, Tapio; Laitinen, Minna; Paavola, Mika; Malmivaara, Antti

    2015-06-01

    Background and purpose - There is no consensus on the treatment of proximal humerus fractures in the elderly. Patients and methods - We conducted a systematic search of the medical literature for randomized controlled trials and controlled clinical trials from 1946 to Apr 30, 2014. Predefined PICOS criteria were used to search relevant publications. We included randomized controlled trials involving 2- to 4-part proximal humerus fractures in patients over 60 years of age that compared operative treatment to any operative or nonoperative treatment, with a minimum of 20 patients in each group and a minimum follow-up of 1 year. Outcomes had to be assessed with functional or disability measures, or a quality-of-life score. Results - After 2 independent researchers had read 777 abstracts, 9 publications with 409 patients were accepted for the final analysis. No statistically significant differences were found between nonoperative treatment and operative treatment with a locking plate for any disability, for quality-of-life score, or for pain, in patients with 3- or 4-part fractures. In 4-part fractures, 2 trials found similar shoulder function between hemiarthroplasty and nonoperative treatment. 1 trial found slightly better health-related quality of life (higher EQ-5D scores) at 2-year follow-up after hemiarthroplasty. Complications were common in the operative treatment groups (10-29%). Interpretation - Nonoperative treatment over locking plate systems and tension banding is weakly supported. 2 trials provided weak to moderate evidence that for 4-part fractures, shoulder function is not better with hemiarthroplasty than with nonoperative treatment. 1 of the trials provided limited evidence that health-related quality of life may be better at 2-year follow-up after hemiarthroplasty. There is a high risk of complications after operative treatment. PMID:25574643

  14. Phase holograms in PMMA with proximity effect correction

    NASA Technical Reports Server (NTRS)

    Maker, Paul D.; Muller, R. E.

    1993-01-01

    Complex computer generated phase holograms (CGPH's) have been fabricated in PMMA by partial e-beam exposure and subsequent partial development. The CGPH was encoded as a sequence of phase delay pixels and written by the JEOL JBX-5D2 E-beam lithography system, a different dose being assigned to each value of phase delay. Following carefully controlled partial development, the pattern appeared rendered in relief in the PMMA, which then acts as the phase-delay medium. The exposure dose was in the range 20-200 micro-C/sq cm, and very aggressive development in pure acetone led to low contrast. This enabled etch depth control to better than plus or minus lambda(sub vis)/60. That result was obtained by exposing isolated 50 micron square patches and measuring resist removal over the central area where the proximity effect dose was uniform and related only to the local exposure. For complex CGPH's with pixel size of the order of the e-beam proximity effect radius, the patterns must be corrected for the extra exposure caused by electrons scattered back up out of the substrate. This has been accomplished by deconvolving the two-dimensional dose deposition function with the desired dose pattern. The deposition function, which plays much the same role as an instrument response function, was carefully measured under the exact conditions used to expose the samples. The devices fabricated were designed with 16 equal phase steps per retardation cycle, were up to 1 cm square, and consisted of up to 100 million 0.3-2.0 micron square pixels. Data files were up to 500 MB long and exposure times ranged to tens of hours. A Fresnel phase lens was fabricated that had diffraction limited optical performance with better than 85 percent efficiency.

  15. Treatment of proximal humerus fractures in the elderly

    PubMed Central

    Launonen, Antti P; Lepola, Vesa; Flinkkilä, Tapio; Laitinen, Minna; Paavola, Mika; Malmivaara, Antti

    2015-01-01

    Background and purpose There is no consensus on the treatment of proximal humerus fractures in the elderly. Patients and methods We conducted a systematic search of the medical literature for randomized controlled trials and controlled clinical trials from 1946 to Apr 30, 2014. Predefined PICOS criteria were used to search relevant publications. We included randomized controlled trials involving 2- to 4-part proximal humerus fractures in patients over 60 years of age that compared operative treatment to any operative or nonoperative treatment, with a minimum of 20 patients in each group and a minimum follow-up of 1 year. Outcomes had to be assessed with functional or disability measures, or a quality-of-life score. Results After 2 independent researchers had read 777 abstracts, 9 publications with 409 patients were accepted for the final analysis. No statistically significant differences were found between nonoperative treatment and operative treatment with a locking plate for any disability, for quality-of-life score, or for pain, in patients with 3- or 4-part fractures. In 4-part fractures, 2 trials found similar shoulder function between hemiarthroplasty and nonoperative treatment. 1 trial found slightly better health-related quality of life (higher EQ-5D scores) at 2-year follow-up after hemiarthroplasty. Complications were common in the operative treatment groups (10–29%). Interpretation Nonoperative treatment over locking plate systems and tension banding is weakly supported. 2 trials provided weak to moderate evidence that for 4-part fractures, shoulder function is not better with hemiarthroplasty than with nonoperative treatment. 1 of the trials provided limited evidence that health-related quality of life may be better at 2-year follow-up after hemiarthroplasty. There is a high risk of complications after operative treatment. PMID:25574643

  16. Monocyclic and Dicyclic Hydrocarbons: Structural Requirements for Proximal Giant Axonopathy

    PubMed Central

    Tshala-Katumbay, Desire D.; Palmer, Valerie S.; Lasarev, Michael R.; Kayton, Robert J.; Sabri, Mohammad I.; Spencer, Peter S.

    2009-01-01

    The chromogenic and neurotoxic ?-diketone 1,2-diacetylbenzene (1,2-DAB), but not it isomer 1,3-DAB, induces blue discoloration of tissues and urine, clustering of axonal microtubules and proximal neurofilament-filled axonal swellings in rodents. The remarkable chromogenic property of 1,2-DAB, a monocyclic aromatic hydrocarbon, arises from reaction with lysine residues of proteins and formation of dimeric and polymeric derivatives. Tetralin, a dicyclic solvent with structural relations to acetyl ethyl tetramethyl tetralin, a chromogenic and neurotoxic agent, reportedly induces excretion of green urine, and causes neurological disturbances in humans. Monocyclic aromatic 1,2,4-Triethylbenzene (1,2,4-TEB), but not its isomer 1,3,5-TEB, is also reportedly chromogenic and induces neurophysiological deficits in rodents consistent with axonal neuropathy, but without neuropathological confirmation. We treated 12 week-old C57Bl/6 mice by gavage with 300, 600, or 900 mg/kg/d 1,2,4-TEB, or equivalent doses of 1,3,5-TEB, 3 days/week, for up to 12 weeks, or intraperitoneally with 400 mg/kg/d tetralin, or 50 or 100 mg/kg/d of its ?-tetralol analogue, 5 days a week, for up to 5 weeks. Animals treated with 1,2,4-TEB, but not 1,3,5-TEB, tetralin or ?-tetralol, developed hind limb weakness, excreted greenish urine, and showed 1,2-DAB-like neuropathology. These findings support the hypothesis that 1,2-spaced ethyl (or acetyl) moieties on a benzene ring of hydrocarbons are required for hydrocarbons to induce chromogenic changes and proximal giant neurofilamentous axonopathy. Key molecular targets of these compounds likely reside in the axon where they serve to maintain normal cytoskeletal organization. PMID:16874529

  17. Thyroid hormones increase Na+-H+ exchange activity in renal brush border membranes.

    PubMed Central

    Kinsella, J; Sacktor, B

    1985-01-01

    Na+-H+ exchange activity, i.e., amiloride-sensitive Na+ and H+ flux, in renal proximal tubule brush border (luminal) membrane vesicles was increased in the hyperthyroid rat and decreased in the hypothyroid rat, relative to the euthyroid animal. A positive correlation was found between Na+-H+ exchange activity and serum concentrations of thyroxine (T4) and triiodothyronine (T3). The thyroid status of the animal did not alter amiloride-insensitive Na+ uptake. The rate of passive pH gradient dissipation was higher in membrane vesicles from hyperthyroid rats compared to the rate in vesicles from hypothyroid animals, a result which would tend to limit the increase in Na+ uptake in vesicles from hyperthyroid animals. Na+-dependent phosphate uptake was increased in membrane vesicles from hyperthyroid rats; Na+-dependent D-glucose and L-proline uptakes were not changed by the thyroid status of the animal. The effect of thyroid hormones in increasing the uptake of Na+ in the brush border membrane vesicle is consistent with the action of the hormones in enhancing renal Na+ reabsorption. Further, the regulation of transtubular Na+ flux has now been shown to be concomitant with modulation of the entry of Na+ into the tubular cell across its luminal membrane, mediated by the exchange reaction, and with the previously reported control of the pumping of Na+ out of the cell across its basolateral membrane, mediated by the Na+,K+-ATPase. PMID:2987936

  18. Proximal renal tubular acidosis: a not so rare disorder of multiple etiologies

    PubMed Central

    Haque, Syed K.; Ariceta, Gema; Batlle, Daniel

    2012-01-01

    Proximal renal tubular acidosis (RTA) (Type II RTA) is characterized by a defect in the ability to reabsorb HCO3 in the proximal tubule. This is usually manifested as bicarbonate wastage in the urine reflecting that the defect in proximal tubular transport is severe enough that the capacity for bicarbonate reabsorption in the thick ascending limb of Henle's loop and more distal nephron segments is overwhelmed. More subtle defects in proximal bicarbonate transport likely go clinically unrecognized owing to compensatory reabsorption of bicarbonate distally. Inherited proximal RTA is more commonly autosomal recessive and has been associated with mutations in the basolateral sodium-bicarbonate cotransporter (NBCe1). Mutations in this transporter lead to reduced activity and/or trafficking, thus disrupting the normal bicarbonate reabsorption process of the proximal tubules. As an isolated defect for bicarbonate transport, proximal RTA is rare and is more often associated with the Fanconi syndrome characterized by urinary wastage of solutes like phosphate, uric acid, glucose, amino acids, low-molecular-weight proteins as well as bicarbonate. A vast array of rare tubular disorders may cause proximal RTA but most commonly it is induced by drugs. With the exception of carbonic anhydrase inhibitors which cause isolated proximal RTA, drug-induced proximal RTA is associated with Fanconi syndrome. Drugs that have been recently recognized to cause severe proximal RTA with Fanconi syndrome include ifosfamide, valproic acid and various antiretrovirals such as Tenofovir particularly when given to human immunodeficiency virus patients receiving concomitantly protease inhibitors such as ritonavir or reverse transcriptase inhibitors such as didanosine. PMID:23235953

  19. Dexamethasone blocks adaptive increase of Na+-Pi cotransport in renal brush border membrane elicited by thyroid hormone.

    PubMed

    Yusufi, A N; Moltaji, H; Dousa, T P

    1989-06-30

    Dexamethasone administered to rats blocks and/or reverses adaptive increases in the rate of Na+-Pi cotransport, and also in the Na+-dependent binding of [14C]-phosphonoformic acid (PFA) by renal brush border membrane (BBM) vesicles elicited by thyroid hormone (T3). In contrast, dexamethasone had no effect on Na+-independent binding of [14C]-phosphonoformic acid, on Na+-dependent transport of D-glucose or on Na+-dependent binding of phlorizin by BBMV which indicates that its inhibitory effect is specific for Na+-Pi cotransport system of BBM. These findings suggest that glucocorticoids antagonize T3-elicited adaptive enhancement of Na+-Pi cotransport in renal proximal tubules by blocking the T3-stimulated de novo synthesis of Na+-Pi symporters and/or their insertion into BBM. PMID:2525901

  20. Emotional and Cognitive Effects of Examination Proximity in Female and Male Students.

    ERIC Educational Resources Information Center

    Martin, Maryanne

    1997-01-01

    Focuses on levels of anxiety and imagery among female and male students in varying proximity to an examination to explain gendered differences in degree classification at Oxford and Cambridge universities. Finds significant, gendered differences in the impact of proximity on anxiety and imagery. Links these findings to differences in degree…

  1. A modified proximity approach in the fusion of heavy-ions

    E-print Network

    Dutt, Ishwar

    2010-01-01

    By using a suitable set of the surface energy coefficient, nuclear radius, and universal function, the original proximity potential 1977 is modified. The overestimate of the data by 4 % reported in the literature is significantly reduced. Our modified proximity potential reproduces the experimental data nicely compared to its older versions.

  2. A modified proximity approach in the fusion of heavy-ions

    E-print Network

    Ishwar Dutt; Rajni Bansal

    2010-10-01

    By using a suitable set of the surface energy coefficient, nuclear radius, and universal function, the original proximity potential 1977 is modified. The overestimate of the data by 4 % reported in the literature is significantly reduced. Our modified proximity potential reproduces the experimental data nicely compared to its older versions.

  3. ANALYSIS OF CONTINUITY AND PROXIMITY EFFECT CONDUCTIVITY LIMITS IN "IN SITU" MULTIFILAMENTARY SUPERCONDUCTING WIRES *

    E-print Network

    Boyer, Edmond

    ANALYSIS OF CONTINUITY AND PROXIMITY EFFECT CONDUCTIVITY LIMITS IN "IN SITU" MULTIFILAMENTARY or the proximity effect is the dominant factor for the high critical current in "in situ" materials. The analysis promise. We discuss the superconducting properties of "in situ'-' materials and focus on the question

  4. Regularization by proximal methods in array-comparative genomic hybridization data analysis

    E-print Network

    Combettes, Patrick Louis

    Regularization by proximal methods in array-comparative genomic hybridization data analysis Saverio Genova) Regularization by proximal methods in aCGH data analysis 1 / 44 #12;Outline 1 Introduction and motivation The new genetics An overview of aCGH technology aCGH data aCGH data analysis S. Salzo (Universit

  5. Proximity sounding analysis for derechos and supercells: an assessment of similarities

    E-print Network

    Doswell III, Charles A.

    Proximity sounding analysis for derechos and supercells: an assessment of similarities) of derechos (long-lived, widespread damaging convective windstorms) and supercells have been obtained. More than 65 derechos, accompanied by 115 proximity soundings, are identified during the years 1983 to 1993

  6. Dominantly inherited proximal myotonic myopathy and leukoencephalopathy in a family with an incidental CLCN1 mutation

    Microsoft Academic Search

    F L Mastaglia; N Harker; B A Phillips; T J Day; G J Hankey; N G Laing; V Fabian; B A Kakulas

    1998-01-01

    A two generation family of Greek origin with mild myotonia, predominantly proximal muscle weakness, and cataracts compatible with the syndrome of proximal myotonic myopathy, is reported. In addition, brain MRI showed a diffuse leukoencephalopathy in the propositus. Molecular genetic studies showed the R894X mutation in exon 23 of the muscle chloride channel gene in the propositus but in only one

  7. Neural Tube Defects and Maternal Residential Proximity to Agricultural Pesticide Applications

    Microsoft Academic Search

    Rudolph P. Rull; Beate Ritz; Gary M. Shaw

    2006-01-01

    Residential proximity to applications of agricultural pesticides may be an important source of exposure to agents that have been classified as developmental toxins. Data on two case-control study populations of infants with neural tube defects (NTDs) and nonmalformed controls delivered in California between 1987 and 1991 were pooled to investigate whether maternal residential proximity to applications of specific pesticides or

  8. Fate of the proximal aortic cuff: Implications for endovascular aneurysm repair

    Microsoft Academic Search

    Karl A. Illig; Richard M. Green; Kenneth Ouriel; Patrick Riggs; Stephen Bartos; James A. DeWeese

    1997-01-01

    Purpose: Long-term success of endoluminally placed grafts for exclusion of abdominal aortic aneurysms (AAAs) relies on secure fixation at the proximal and distal cuffs and, as such, assumes that the fixation sites will not dilate over time. Data regarding this issue, however, are not yet available. This study was performed to evaluate the region of the proximal anastomosis in patients

  9. The energy density of jellyfish: Estimates from bomb-calorimetry and proximate-composition

    E-print Network

    Hays, Graeme

    The energy density of jellyfish: Estimates from bomb-calorimetry and proximate-composition Thomas K scyphozoan jellyfish (Cyanea capillata, Rhizostoma octopus and Chrysaora hysoscella). First, bomb). These proximate data were subsequently converted to energy densities. The two techniques (bomb- calorimetry

  10. Accuracy of Color-Doppler in the Quantification of Proximal Vertebral Artery Stenoses

    Microsoft Academic Search

    J. M. de Bray; A. Pasco; F. Tranquart; X. Papon; C. Alecu; B. Giraudeau; F. Dubas; J. Emile

    2001-01-01

    Background: Vertebrobasilar (VB) strokes appear to have the same causes as carotid strokes. Obstructive lesions of proximal vertebral arteries probably occur in about 30% of stroke patients. Purpose: Our aim was to assess the validity of color Doppler sonography compared to selective intra-arterial angiography in the quantification of proximal vertebral artery stenoses. Materials and Methods: A prospective blind study of

  11. Detecting proximity from personal audio recordings Daniel P. W. Ellis1

    E-print Network

    Ellis, Dan

    are in close proximity by de- tecting the similarity between the acoustic ambience recorded by body-worn mics. This paper investigates two techniques for proximity detection on a database of personal audio recordings, correlation, acoustic landmark, fingerprinting 1. Introduction The huge uptake of smartphones leads to many

  12. A VU-proximal point algorithm for minimization Robert Mi in and Claudia Sagastiz abal y

    E-print Network

    Mifflin, Robert

    A VU-proximal point algorithm for minimization Robert Mi#15;in #3; and Claudia Sagastiz#19;abal y June 1, 2002 Abstract For convex optimization, VU-space decomposition algorithms make a minimization. Keywords Convex minimization, proximal points, bundle methods, VU-decomposition. 1 Introduction. Motivation

  13. Maintaining Interaction at the Zone of Proximal Development through Reflexive Practice and Action Research

    ERIC Educational Resources Information Center

    Lisle, Angela

    2006-01-01

    In this study, dialectical reflexive practice is used to maintain student-teacher interactions in the zone of proximal development. The zone of proximal development is the development-and-learning unit of the child or learner and the author suggests that it is also the fusion point of Marx's dialectical historical materialism: the creation of…

  14. Modeling the effects of temporal proximity of input transitions on gate propagation delay and transition time

    Microsoft Academic Search

    V. Chandramouli; Karem A. Sakallah

    1996-01-01

    Abstract While delay modeling of gates with a single switching input has received a lot of attention, the case of multiple inputs switching in close temporal proximity is just beginning to be addr essed in the literature. The effect of proximity of input transi- tions can be significant on the delay and output transition time. The few attempts that have

  15. Multifunctional CMC\\/silicone composite sensor elements as the tactile and proximity sensors

    Microsoft Academic Search

    H. Natsuhara; T. Katsuno; X. Chen; S. Yang; S. Motojima; M. Takaki; T. Kuzuya; K. Kawabe

    2006-01-01

    The tactile and proximity sensing properties of CMC\\/silicone composites were studied by evaluating with the impedance Z as a function of CMC content in matrix. The optimum CMC content as proximity sensor element was 3 wt%, while the tactile sensor properties were increased in intensity with CMC content (over 7 wt%). The CMC sensor element with surface size of 300

  16. Effects of peritubular oncotic pressure on rat proximal tubule electrical resistance

    Microsoft Academic Search

    John F Seely

    1973-01-01

    Effects of peritubular oncotic pressure on rat proximal tubule electrical resistance. The effects of peritubular oncotic pressure changes upon the electrical resistance of the rat proximal tubule were studied by cable analysis of voltage attenuation experiments during normal capillary blood flow and following peritubular capillary perfusions containing varying concentrations of Dextran or albumin. Hypooncotic and hyperoncotic perfusions led to significant

  17. Relationship between peritubular oncotic pressure gradients and morphology in isolated proximal tubules

    Microsoft Academic Search

    C Craig Tisher; Juha P Kokko

    1974-01-01

    Relationship between peritubular oncotic pressure gradients and morphology in isolated proximal tubules. Previous studies have demonstrated that net sodium and water flux across the isolated perfused proximal convoluted tubule of the rabbit can be increased by elevating the protein concentration of the bath and at least part of the protein effect is mediated through oncotic forces. This study was designed

  18. Optimisation of proximity measures for aircraft with uniform 3D straight motion

    Microsoft Academic Search

    T he engineering specifications that define aircraft proximity management functions are currently under an intense review. Simultaneously, in an operational context, the frequency of aircraft proximity incidents is anticipated to increase due to the growth in traditional air travel, and the introduction of aerial vehicle operations (without a human pilot), and of personalised jets. The design of the airspace rules

  19. Proximity effect in planar superconducting tunnel junctions containing Nb/NiCu superconductor/ferromagnet bilayers

    E-print Network

    Fominov, Yakov

    such as superconducting radiation detectors.10 The question of the proximity effect in the presence of a ferromagnetic Physics RAS, 119334 Moscow, Russia 4Nuclear Physics Institute, Moscow State University, 119899 Moscow from a proximity model for S/F bilayers in the dirty limit in the framework of Usadel equations

  20. Wall proximity corrections for hot-wire readings in turbulent flows

    NASA Technical Reports Server (NTRS)

    Hebbar, K. S.

    1980-01-01

    This note describes some details of recent (successful) attempts of wall proximity corrections for hot-wire measurements performed in a three-dimensional incompressible turbulent boundary layer. A simple and quite satisfactory method of estimating wall proximity effects on hot-wire readings is suggested.

  1. Pirates: proximity-triggered interaction in a multi-player game

    Microsoft Academic Search

    Jennica Falk; Peter Ljungstrand; Staffan Bjtirk; Rebecca Hansson

    2001-01-01

    We show how proximity-sensing technology can be integrated into computer game design to provide richer game experiences in social settings. To explore the theme of proximity-triggered interaction, we have constructed Pirates! -- a multi-player, wireless computer game for handheld computers, played throughout a physical environment. The players' physical locations in the environment trigger game events.

  2. Proximal Postural Control Mechanisms May Be Exaggeratedly Adopted by Individuals With Peripheral Deficiencies: A Review

    Microsoft Academic Search

    Cédrick T. Bonnet; Marc Lepeut

    2011-01-01

    In quiet stance, it is understood that healthy individuals control their posture primarily by a peripheral mechanism for anteroposterior sway and by a proximal mechanism for medialateral sway. The authors proposed the hypothesis that patients suffering from disease-related deficiencies, at their feet and legs, may exaggeratedly adopt proximal control mechanisms at their hip in the anteroposterior and medialateral axes. They

  3. Classifying Proximity Soundings with Self-Organizing Maps toward Improving Supercell and Tornado Forecasting

    E-print Network

    Classifying Proximity Soundings with Self-Organizing Maps toward Improving Supercell and Tornado important when forecasting tornadoes. 1. Introduction A wide breadth of work examining supercell thunder not preclude the possibility of supercells or tornadoes. Proximity sound- ings obtained from radiosonde

  4. Two complementary methods to characterize long range proximity effects due to develop loading

    Microsoft Academic Search

    Linda K. Sundberg; Greg M. Wallraff; Alexander M. Friz; Blake Davis; Amy E. Zweber; Robert Lovchik; Emmanuel Delamarche; Tasuku Senna; Toru Komizo; William D. Hinsberg

    2010-01-01

    Variations in critical dimension (CD) as a function of the proximity of an individual feature to other exposed areas are a continuing problem both in mask fabrication and in optical lithography. For example, the CD uniformity (CDU) may degrade significantly depending on the proximity to densely or sparsely exposed areas. These pattern density effects will continue to worsen as feature

  5. Straining of the intact and fractured proximal humerus under physiological-like loading

    Microsoft Academic Search

    Zully M. Maldonado; Jörn Seebeck; Markus O. W. Heller; Doris Brandt; Pierre Hepp; Helmut Lill; Georg N. Duda

    2003-01-01

    Surgical treatment of proximal humeral fractures remains challenging in elderly patients, primarily due to insufficient implant fixation. Both bone quality and physiological-like loading conditions are commonly overlooked during pre-clinical in vitro evaluation. However, this knowledge is necessary in order to improve surgical treatment of the proximal humerus and the mechanical behavior of implants, particularly in patients with complex fractures and

  6. Proximate, mineral and fatty acid composition of fast foods consumed in Bahrain

    Microsoft Academic Search

    Abdulrahman O. Musaiger; Jassim H. Al-Jedah; Reshma Dsouza

    2008-01-01

    Purpose – The purpose of this paper is to evaluate the commonly consumed fast foods in Bahrain with respect to proximate, mineral, sterol composition and their fatty acid profile. Design\\/methodology\\/approach – Foods were purchased from the most frequented fast food outlets in Manama city, the capital of Bahrain. Similar types of foods were pooled into one sample. Proximate composition was

  7. Requirements for proximal tubule epithelial cell detachment in response to ischemia: Role of oxidative stress

    Microsoft Academic Search

    David Sáenz-Morales; María M. Escribese; Konstantinos Stamatakis; María García-Martos; Laura Alegre; Elisa Conde; Dolores Pérez-Sala; Francisco Mampaso; M. Laura García-Bermejo

    2006-01-01

    Sublethal renal ischemia induces tubular epithelium damage and kidney dysfunction. Using NRK-52E rat proximal tubular epithelial cells, we have established an in vitro model, which includes oxygen and nutrients deprivation, to study the proximal epithelial cell response to ischemia. By means of this system, we demonstrate that confluent NRK-52E cells lose monolayer integrity and detach from collagen IV due to:

  8. An Analysis of the Relationship between Residents' Proximity to Water and Attitudes about Resource Protection

    Microsoft Academic Search

    Kelli L. Larson; Mary V. Santelmann

    2007-01-01

    This article investigates attitudes toward water resource protection among residents in varying proximities to resources, specifically to identify attitudinal differences and the extent to which nearness and adjacency explain attitudes. Proximity was evaluated by measured distances using GIS and reported closeness from a mail survey. Five attitudinal dimensions were assessed: general importance of resource protection, support for government, regulations, and

  9. Proximity and Visibility of Fruits and Vegetables Influence Intake in a Kitchen Setting among College Students

    ERIC Educational Resources Information Center

    Privitera, Gregory J.; Creary, Heather E.

    2013-01-01

    The hypothesis that participants will eat more fruits (apple slices) and vegetables (carrot cuts) if they are made more proximate and visible was tested using a 2 × 2 between-participants design. Proximity was manipulated by placing fruits and vegetables in a bowl at a table where participants sat (near) or 2 m from the table (far). Visibility was…

  10. Reduced bird occurrence in pine forest fragments associated with road proximity in a Mediterranean agricultural area

    Microsoft Academic Search

    Llu??s Brotons; Sergi Herrando

    2001-01-01

    This study investigated the effect of road and highway proximity on the occurrence of bird species in isolated secondary pine forest fragments in an agricultural matrix. We assessed the effects of road proximity separately for three different groups of bird species in order to detect ecological responses related to species biology. Bird occurrence was mainly related to fragment size but

  11. Thyroid hormone modulates rabbit proximal straight tubule paracellular permeability

    PubMed Central

    Baum, Michel; Quigley, Raymond

    2014-01-01

    Proximal straight tubules (PST) from both neonatal and hypothyroid adult rabbits have a lower rate of passive volume absorption when perfused with a high-chloride solution simulating late proximal tubular fluid than adult rabbit PST. We hypothesized that the maturational increase in serum thyroid hormone levels mediates the developmental changes in PST paracellular permeability. Neonatal tubules had lower chloride permeability, higher transepithelial resistance, but comparable mannitol permeability compared with adult PST. The present in vitro microperfusion study directly examined whether thyroid hormone affects passive solute flux and whether thyroid hormone could explain the developmental changes in PST paracellular permeability. Passive chloride transport was 62.1 ± 4.5, 23.1 ± 7.7, and 111.6 ± 5.6 pmol·mm?1·min?1 in PST from euthyroid, hypothyroid, and hypothyroid animals that received thyroid treatment, respectively (control different from hypothyroid and thyroid treatment at P < 0.05). This was due to a thyroid hormone-mediated change in chloride permeability (PCl). Mannitol permeability was 3.65 + 1.03, ?0.19 + 0.72, and 3.60 + 1.12 × 10?6 cm/s in PST from euthyroid animals, hypothyroid animals, and hypothyroid rabbits that received thyroid replacement, respectively (P < 0.05 hypothyroid vs. euthyroid and thyroid replacement). We demonstrate that PST from hypothyroid animals have a higher passive PNa/PCl and PHCO3/PCl than euthyroid controls. Finally, we examined whether these changes in permeability were paralleled by a change in PST paracellular resistance. Resistance was measured by current injection and cable analysis. The resistance in PST from hypothyroid rabbits was 6.3 ± 0.8 ?·cm2, which was not different from control of 4.8 ± 0.7 ?·cm2, or 7.0 ± 0.7 ?·cm2 in hypothyroid animals that received thyroid replacement. Therefore, the maturational increase in thyroid hormone levels does not fully explain the developmental changes in the paracellular pathway. PMID:14644749

  12. Interaction of ion tracks in spatial and temporal proximity.

    PubMed

    Kreipl, Maximilian Stephan; Friedland, Werner; Paretzke, Herwig G

    2009-11-01

    In the present work, a systematic analysis of the impact of spatial and temporal proximity of ion tracks on the yield of higher-order radiolytic species as well as of DNA damage patterns is presented. This potential impact may be of concern when laser-driven particle accelerators are used for ion radiation therapy. The biophysical Monte Carlo track structure code PARTRAC was used and, to this end, extended in two aspects: first, the temporal information about track evolution has been included in the track structure module and, second, the simulation code has been modified to enable parallel multiple track processing during simulation of subsequent modelling stages. Depending on the spatial and temporal separation between ion-track pairs, the yield of chemical species has been calculated for incident protons with start energies of 20 MeV, for He(2+) ions with start energies of 1 and 20 MeV, and for 60 MeV C(6+) ions. Provided the overlap of the considered ion tracks is sufficient in all four dimensions (space and time), the yield of hydroxyl radicals was found to be reduced compared to that of single tracks, for all considered ion types. The biological endpoints investigated were base damages, single-strand breaks, double-strand breaks, and clustered lesions for incident pairs of protons and He(2+) ions, each with start energies of 20 MeV. The yield of clustered lesions produced by 20 MeV protons turned out to be influenced by the spatial separation of the proton pair; in contrast, no influence was found for different start times of the protons. The yield of single-strand breaks and base hits was found neither to depend on the spatial separation nor on the temporal separation between the incident protons. For incident 20 MeV He(2+) ions, however, a dependence on the spatial and temporal separation of the ion pair was found for all considered biological endpoints. Nevertheless, spatial proximity conditions where such intertrack effects were obtained are not met in the case of tumour radiation therapy; thus, no impact on radiation effects due to short pulse duration of laser-driven accelerators can be expected from alterations during the chemical stage. PMID:19597739

  13. Longitudinal and Circumferential Strain of the Proximal Aorta

    PubMed Central

    Bell, Vanessa; Mitchell, William A.; Sigurðsson, Sigurður; Westenberg, Jos J. M.; Gotal, John D.; Torjesen, Alyssa A.; Aspelund, Thor; Launer, Lenore J.; de Roos, Albert; Gudnason, Vilmundur; Harris, Tamara B.; Mitchell, Gary F.

    2014-01-01

    Background Accurate assessment of mechanical properties of the proximal aorta is a requisite first step for elucidating the pathophysiology of isolated systolic hypertension. During systole, substantial proximal aortic axial displacement produces longitudinal strain, which we hypothesize causes variable underestimation of ascending aortic circumferential strain compared to values in the longitudinally constrained descending aorta. Methods and Results To assess effects of longitudinal strain, we performed magnetic resonance imaging in 375 participants (72 to 94 years old, 204 women) in the Age, Gene/Environment Susceptibility?Reykjavik Study and measured aortic circumferential and longitudinal strain. Circumferential ascending aortic area strain uncorrected for longitudinal strain was comparable in women and men (mean [95% CI], 8.3 [7.8, 8.9] versus 7.9 [7.4, 8.5]%, respectively, P=0.3). However, longitudinal strain was greater in women (8.5±2.5 versus 7.0±2.5%, P<0.001), resulting in greater longitudinally corrected circumferential ascending aortic strain (14.4 [13.6, 15.2] versus 13.0 [12.4, 13.7]%, P=0.010). Observed circumferential descending aortic strain, which did not require correction (women: 14.0 [13.2, 14.8], men: 12.4 [11.6, 13.2]%, P=0.005), was larger than uncorrected (P<0.001), but comparable to longitudinally corrected (P=0.12) circumferential ascending aortic strain. Carotid?femoral pulse wave velocity did not correlate with uncorrected ascending aortic strain (R=?0.04, P=0.5), but was inversely related to longitudinally corrected ascending and observed descending aortic strain (R=?0.15, P=0.004; R=?0.36, P<0.001, respectively). Longitudinal strain was also inversely related to carotid?femoral pulse wave velocity and other risk factors for higher aortic stiffness including treated hypertension. Conclusions Longitudinal strain creates substantial and variable errors in circumferential ascending aortic area strain measurements, particularly in women, and should be considered to avoid misclassification of ascending aortic stiffness. PMID:25523153

  14. Spatial proximity amplifies valence in emotional memory and defensive approach-avoidance.

    PubMed

    Åhs, Fredrik; Dunsmoor, Joseph E; Zielinski, David; LaBar, Kevin S

    2015-04-01

    In urban areas, people often have to stand or move in close proximity to others. The egocentric distance to stimuli is a powerful determinant of defensive behavior in animals. Yet, little is known about how spatial proximity to others alters defensive responses in humans. We hypothesized that the valence of social cues scales with egocentric distance, such that proximal social stimuli have more positive or negative valence than distal stimuli. This would predict enhanced defensive responses to proximal threat and reduced defensive responses to proximal reward. We tested this hypothesis across four experiments using 3-D virtual reality simulations. Results from Experiment 1 confirmed that proximal social stimuli facilitate defensive responses, as indexed by fear-potentiated startle, relative to distal stimuli. Experiment 2 revealed that interpersonal defensive boundaries flexibly increase with aversive learning. Experiment 3 examined whether spatial proximity enhances memory for aversive experiences. Fear memories for social threats encroaching on the body were more persistent than those acquired at greater interpersonal distances, as indexed by startle. Lastly, Experiment 4 examined how egocentric distance influenced startle responses to social threats during defensive approach and avoidance. Whereas fear-potentiated startle increased with proximity when participants actively avoided receiving shocks, startle decreased with proximity when participants tolerated shocks to receive monetary rewards, implicating opposing gradients of distance on threat versus reward. Thus, proximity in egocentric space amplifies the valence of social stimuli that, in turn, facilitates emotional memory and approach-avoidance responses. These findings have implications for understanding the consequences of increased urbanization on affective interpersonal behavior. PMID:25541499

  15. Expert opinion: diagnosis and treatment of proximal hamstring tendinopathy

    PubMed Central

    Lempainen, Lasse; Johansson, Kristian; Banke, Ingo J.; Ranne, Juha; Mäkelä, Keijo; Sarimo, Janne; Niemi, Pekka; Orava, Sakari

    2015-01-01

    Summary Background: proximal hamstring tendinopathy (PHT) is a disabilitating disease often causing underperformance in the athletically demanding patients. The main symptom of PHT is lower gluteal pain especially during running or while prolonged sitting. Mainly affecting athletically active individuals, PHT is a considerable challenge for treating health care professionals. Purpose: this paper aims to concisely present the literature on PHT to guide health care professionals treating these patients and doing research on the subject. Methods: we reviewed the literature on PHT through literature search of scientific journal databases. Conclusions: as a tendinopathic pathology, it is a rather recently discovered exertion injury. As with other chronic tendon overuse injuries, current treatment strategies are unspecific with uncertain outcomes due to the unknown etiology of the tendon degeneration. Diagnostic features as well as both operative and non-operative treatments are evaluated from a clinical perspective, providing up to date information for clinicians and sports medicine therapists dealing with hamstring problems. Level of evidence: V. PMID:25878983

  16. Proximity effect in superconductor/conical magnet heterostructures.

    PubMed

    Fritsch, D; Annett, J F

    2014-07-01

    The presence of a spin-flip potential at the interface between a superconductor and a ferromagnetic metal allows for the generation of equal-spin spin-triplet Cooper pairs. These Cooper pairs are compatible with the exchange interaction within the ferromagnetic region and hence allow for the long-range proximity effect through a ferromagnet or half-metal. One suitable spin-flip potential is provided by incorporating the conical magnet Holmium (Ho) into the interface. The conical magnetic structure is characterised by an opening angle ? with respect to the crystal c-axis and a turning (or pitch) angle ? measuring the rotation of magnetisation with respect to the adjacent layers. Here, we present results showing the influence of conical magnet interface layers with varying ? and ? on the efficiency of the generation of equal-spin spin-triplet pairing. The results are obtained by self-consistent solutions of the microscopic Bogoliubov-de Gennes equations in the clean limit within a tight-binding model of the heterostructure. In particular, the dependence of unequal-spin and equal-spin spin-triplet pairing correlations on the conical magnetic angles ? and ? are discussed in detail. PMID:24934542

  17. Do proximate, C. elegans swimmers synchronize their gait?

    NASA Astrophysics Data System (ADS)

    Yuan, Jinzhou; Raizen, David; Bau, Haim

    2012-11-01

    We imaged two C. elegans swimming, one after the other, in a tapered conduit. The conduit was subjected to a DC electric field, with the negative pole at the narrow end and applied flow directed from the narrow end. As a result of their attraction to the negative pole (electrotaxis), both animals swam upstream. As the conduit narrowed, the average adverse flow velocity increased and the swimming speed of the leading animal decreased faster than that of the trailing animal, allowing the latter to catch up with the former. We quantified synchronization by measuring the phase lag between the gait of one animal and the extended wave pattern of the other as a function of the distance between the two animals. Only when the distance between the two animals' body centers was nearly equal to or smaller than one body length were the animals' motions synchronized. When the nematodes were parallel to one another, synchronization was essential to prevent the animals from colliding. Direct numerical simulations indicate that when the trailing animal's head is immediately downstream of the leading animal's tail, the animals derive just a slight hydrodynamic advantage from their proximity compared to a single swimmer. We thank Kun He Lee from the University of Pennsylvania for preparing C. elegans.

  18. Dynamics and control of satellite relative motion in proximity operations

    NASA Astrophysics Data System (ADS)

    Okasha, Mohamed Elsayed Aly Abd Elaziz

    In this dissertation, the development of relative navigation, guidance, and control algorithms of an autonomous space rendezvous and docking system are presented. These algorithms are based on innovative formulations of the relative motion equations that are completely explicit in time. The navigation system uses an extended Kalman filter based on these formulations to estimate the relative position and velocity of the chaser vehicle with respect to the target vehicle and the chaser attitude and gyro biases. This filter uses the range and angle measurements of the target relative to the chaser from a simulated LIDAR system, along with the star tracker and gyro measurements of the chaser. The corresponding measurement models, process noise matrix, and other filter parameters are provided. The guidance and control algorithms are based on the glideslope used in the past for rendezvous and proximity operations of the Space Shuttle with other vehicles. These algorithms are used to approach, flyaround, and to depart from a target vehicle in elliptic orbits. The algorithms are general and able to translate the chaser vehicle in any direction, decelerate while approaching the target vehicle, and accelerate when moving away. Numerical nonlinear simulations that illustrate the relative navigation, attitude estimation, guidance, and control algorithm's, as well as performance and accuracy are evaluated in the research study.

  19. Proximate sources of population sex imbalance in india.

    PubMed

    Osters, Emily

    2009-05-01

    There is a population sex imbalance in India. Despite a consensus that this imbalance is due to excess female mortality, the specific source of this excess mortality remains poorly understood. I use microdata on child survival in India to analyze the proximate sources of the sex imbalance. I address two questions: when in life does the sex imbalance arise, and what health or nutritional investments are specifically responsible for its appearance? I present a new methodology that uses microdata on child survival. This methodology explicitly takes into account both the possibility of naturally occurring sex differences in survival and possible differences between investments in their importance for survival. Consistent with existing literature, I find significant excess female mortality in childhood, particularly between the ages of 1 and 5, and argue that the sex imbalance that exists by age 5 is large enough to explain virtually the entire imbalance in the population. Within this age group, sex differences in vaccinations explain between 20% and 30% of excess female mortality, malnutrition explains an additional 20%, and differences in treatment for illness play a smaller role. Together, these investments account for approximately 50% of the sex imbalance in mortality in India. PMID:21305396

  20. Hard proximity induced superconducting gap in semiconductor - superconductor epitaxial hybrids

    NASA Astrophysics Data System (ADS)

    Jespersen, Thomas; Krogstrup, Peter; Ziino, Nino; Albrecht, Sven; Chang, Willy; Madsen, Morten; Johnson, Erik; Kuemmeth, Ferdinand; Nygård, Jesper; Marcus, Charles

    2015-03-01

    We present molecular beam epitaxy grown InAs semiconductor nanowires capped with a shell of aluminum (superconductor). The hybrid wires are grown without breaking vacuum, resulting in an epitaxial interface between the two materials as demonstrated by detailed transmission electron microscopy and simulations. The domain matching at the interface is discussed. Incorporating the epitaxial nanowire hybrids in electrical devices we performed detailed tunneling spectroscopy of the proximity induced superconducting gap in the InAs core at 20 mK. We find the sub-gap conductance being at least a factor 200 smaller than the normal state value (gap hardness). This is a significant improvement compared to devices fabricated by conventional lithographic methods and metal evaporation showing no more than a factor of ~ 5 . The epitaxial hybrids seem to solve the soft gap problem associated with the use of nanowire hybrids for future applications in topological quantum information based on Majorana zero modes. Research supported by Microsoft Station Q, Danish National Research Foundation, Villum Foundation, Lundbeck Foundation, and the European Commission.

  1. Autonomous control procedures for shuttle rendezvous proximity operations

    NASA Technical Reports Server (NTRS)

    Lea, Robert N.; Mitchell, Eric V.; Goodwin, Mary Ann

    1987-01-01

    The results are presented of a study which uses fuzzy sets to model a Space Shuttle pilot's reasoning and actions while performing rendezvous proximity operation maneuvers. In this model fuzzy sets are used to simulate smooth and continuous actions as would be expected from an experienced pilot and to simulate common sense reasoning in the decision process. The present model assumes visual information available to the Shuttle pilot from the Shuttle Crew Optical Alignment Sighting (COAS) device and the overhead window and rendezvous radar sensor information available to him from an onboard display. This model will be used in a flight analysis simulator to perform studies requiring a large number of runs, each of which currently needs an engineer in the loop to supply the piloting decisions. This work has much broader implications in control of robots such as the Flight Telerobotic Servicer, in automated pilot control and attitude control, and in advisory and evaluation functions that could be used for flight data monitoring or for testing of various rule sets in flight preparation.

  2. Topological proximity effect in a topological insulator hybrid.

    PubMed

    Shoman, T; Takayama, A; Sato, T; Souma, S; Takahashi, T; Oguchi, T; Segawa, Kouji; Ando, Yoichi

    2015-01-01

    It is well known that a topologically protected gapless state appears at an interface between a topological insulator and an ordinary insulator; however, the physics of the interface between a topological insulator and a metal has largely been left unexplored. Here we report a novel phenomenon termed topological proximity effect, which occurs between a metallic ultrathin film and a three-dimensional topological insulator. We study one bilayer of bismuth metal grown on the three-dimensional topological insulator material TlBiSe2, and by using spin- and angle-resolved photoemission spectroscopy, we found evidence that the topological Dirac-cone state migrates from the surface of TlBiSe2 to the attached one-bilayer Bi. We show that such a migration of the topological state occurs as a result of strong spin-dependent hybridization of the wave functions at the interface, which is also supported by our first-principles calculations. This discovery points to a new route to manipulating the topological properties of materials. PMID:25761780

  3. Multilayered graphene acquires ferromagnetism in proximity with magnetite particles

    NASA Astrophysics Data System (ADS)

    Seifu, Dereje; Neupane, Suman; Giri, Lily; Karna, Shashi P.; Hong, Haiping; Seehra, M. S.

    2015-05-01

    Anisotropic diamagnetism of pristine graphite and graphene is well known. Here, evidence of significant induced ferromagnetism in multilayer graphene (MLG) decorated with ferrimagnetic Fe3O4 particles is reported. This MLG-Fe3O4 nano-composite was prepared by a one-step ultrasonic treatment at 75 °C in the surfactant sodium dodecyl-benzene-sulfonate. To verify the phase structure and morphology of the composite, X-ray diffraction, scanning and transmission electron microscopy, scanning tunneling electron microscopy, and Raman spectroscopy were employed. Room temperature data of magnetization versus magnetic field showed that the saturation magnetization MS = 58.6 emu/gm for pristine Fe3O4 increased to MS = 158.4 emu/gm for a 1:1 composite of Fe3O4 to MLG. These results lead to induced MS = 253 emu/gm in MLG resulting from its proximity to Fe3O4. Similar experiments on Fe3O4 to single walled carbon nanotubes (SWNT) composite did not show any induced magnetism in SWNT.

  4. Orbit Determination of Hayabusa during Close Proximity Phase

    NASA Astrophysics Data System (ADS)

    Ikeda, Hitoshi; Kominato, Takashi; Matsuoka, Masatoshi; Ohnishi, Takafumi; Yoshikawa, Makoto

    In September 2005, Hayabusa (MUSES-C) spacecraft successfully had a rendezvous with asteroid 25143 Itokawa. After the arrival, Hayabusa made detailed observations of the asteroid during its rendezvous period (about three months). As the results of various kinds of scientific analysis, a variety of physical parameters of Itokawa (e.g. size, volume, mass, and density) were derived. As to the orbit determination of Hayabusa spacecraft, during the cruise phase, the radiometric (2-way X-band range and Doppler) data were used for analysis. On the other hand, during the approach phase or rendezvous phase, we could obtain the optical data by means of star tracker or optical navigation camera, thus both the radiometric and the optical data were used for orbit determination. The present paper will report on the results of the orbit determination of Hayabusa during the close proximity phase. We will also mention about the mass estimation of Itokawa in this period. The data used in this analysis are 2-way X-band Doppler data and the position data, which were calculated from optical navigation camera's data. As well as the large orbital maneuvers and the gravitational acceleration of Itokawa, the effect of solar radiation pressure, and the effect of attitude control are also taken into account for the calculation. As to the gravity model of Itokawa, a spherical-harmonics gravity model or a polyhedron gravity model are used depending on the situation.

  5. [Proximal and distal ruptures of the biceps brachii tendon].

    PubMed

    Klonz, A; Loitz, D; Reilmann, H

    2003-09-01

    Proximal ruptures. Ruptures of the long head of the M. biceps humeri are commonly caused by degenerative changes within the tendon. Non-operative treatment gives good results, the loss of power regarding elbow flexion and supination amounts to only 8-21%. Refixation may be indicated for cosmetic reasons and offers a small but evident improvement of flexion and supination power. Deformity of the slipped muscle can be corrected effectively. Residual complaints after conservative treatment often result from associated subacromial problems. Distal ruptures. Ruptures of the distal tendon should be treated operatively. The loss of power after conservative treatment is evident (30-40% for flexion, >50% for supination). Extra-anatomical tenodesis to the brachialis muscle or anatomical fixation to the radial tuberosity can be applied. Flexion power and cosmesis can be addressed by both techniques. If supination strength is to be restored, the tendon has to be fixed anatomically. Preparation of the tuberosity bears the risk of heterotopic ossification or nerve damage. Mini-open techniques, using only a limited anterior approach, may decrease risks. PMID:14959750

  6. Fermi surface topology in the proximity to the Mott insulator

    NASA Astrophysics Data System (ADS)

    Yamaji, Youhei; Imada, Masatoshi

    2010-03-01

    Since the discovery of cuprate superconductors, how its low energy electronic excitations evolve with doping has attracted much attention. The normal metallic state offers a typical example of strongly correlated metallic state. Recent experiments suggest the existence of the k-dependent renormalized quasiparticle [1], or more drastic reconstruction of the Fermi surface [2]. Numerical theories on the two-dimensional Hubbard model also predict the reconstruction of the Fermi surface [3]. We propose a scenario for the Fermi surface reconstruction in the proximity to the Mott insulator based on the simple slave-boson mean-field theory [4] including charge fluctuations [5]. The key idea is the emergence of new fermionic excitations consisting of charge bosons and low energy coherent electrons, and occurrence of topological changes in the Fermi surface. We also discuss relation between the topological changes and superconductivities. [1] As a review, A. Damascelli, Z. Hussain, and Z.-X. Shen, Rev. Mod. Phys. 75, 473 (2003). [2] J. Meng, et al., arXiv: 0906.2682v1. [3] For example, T. D. Stanescu and G. Kotliar, Phys. Rev. B 74, 125110 (2006). [4] G. Kotliar, and A. E. Ruckenstein: Phys. Rev. Lett. 57, 1362 (1987). [5] R. Raimondi, and C. Castellani; Phys. Rev. B 48, 11453 (1993).

  7. Fractures of the Proximal Fifth Metatarsal: Percutaneous Bicortical Fixation

    PubMed Central

    Mahajan, Vivek; Chung, Hyun Wook

    2011-01-01

    Background Displaced intraarticular zone I and displaced zone II fractures of the proximal fifth metatarsal bone are frequently complicated by delayed nonunion due to a vascular watershed. Many complications have been reported with the commonly used intramedullary screw fixation for these fractures. The optimal surgical procedure for these fractures has not been determined. All these observations led us to evaluate the effectiveness of percutaneous bicortical screw fixation for treating these fractures. Methods Twenty-three fractures were operatively treated by bicortical screw fixation. All the fractures were evaluated both clinically and radiologically for the healing. All the patients were followed at 2 or 3 week intervals till fracture union. The patients were followed for an average of 22.5 months. Results Twenty-three fractures healed uneventfully following bicortical fixation, with a mean healing time of 6.3 weeks (range, 4 to 10 weeks). The average American Orthopaedic Foot & Ankle Society (AOFAS) score was 94 (range, 90 to 99). All the patients reported no pain at rest or during athletic activity. We removed the implant in all cases at a mean of 23.2 weeks (range, 18 to 32 weeks). There was no refracture in any of our cases. Conclusions The current study shows the effectiveness of bicortical screw fixation for displaced intraarticular zone I fractures and displaced zone II fractures. We recommend it as one of the useful techniques for fixation of displaced zone I and II fractures. PMID:21629475

  8. The proximity effect around high-redshift galaxies

    NASA Astrophysics Data System (ADS)

    Maselli, A.; Ferrara, A.; Bruscoli, M.; Marri, S.; Schneider, R.

    2004-05-01

    Recent observations have shown that the intergalactic medium (IGM) is more transparent to Ly? photons close to Lyman break galaxies (LBGs) than at large distance from them, i.e. there is a proximity effect. Cosmological simulations including winds from LBGs have been so far unable to explain this trend. By coupling such simulations with the radiative transfer code CRASH, we investigate whether the addition of the ionizing radiation emitted by LBGs can increase the transmissivity by decreasing the neutral hydrogen fraction in the inner Mpc of the galaxy halo. The transmissivity as a function of distance is roughly reproduced only if LBGs are identified with dwarf galaxies (with masses <~ 109 Msolar) which are undergoing a vigorous (50 Msolar yr-1) burst of star formation. Similar star formation rates in larger galaxies are not sufficient to overwhelm the large recombination rates associated with their denser environment. If so, photoionization partly reconciles theory with observations, although we discuss a number of uncertainties affecting both approaches.

  9. The proximity of hotspots to convergent and divergent plate boundaries

    NASA Technical Reports Server (NTRS)

    Weinstein, Stuart A.; Olson, Peter L.

    1989-01-01

    An analysis of four different hotspot distributions, ranging from Morgan's (1972) original list of 19 to Vogt's (1981) list of 117 reveals that the hotspots are preferentially located near divergent plate boundaries. The probability of this proximity occurring by chance alone is quite remote, less than 0.01 for all four hotspot distributions. The same analysis also reveals that the hotspots are preferentially excluded from regions near convergent plate boundaries. The probability of this exclusion occurring by chance alone is 0.1 or less for three out of the four distributions examined. We interpret this behavior as being a consequence of the effects of large scale convective circulation on ascending mantle plumes. Mantle thermal plumes, the most probable source of hotspots, arise from instabilities in a basal thermal boundary layer. Plumes are suppressed from regions beneath convergent boundaries by descending flow and are entrained into the upwelling flow beneath spreading centers. Plate-scale convective circulation driven by subduction may also advect mantle thermal plumes toward spreading centers.

  10. A Review of Management Options for Proximal Humeral Fractures

    PubMed Central

    Jordan, Robert W; Modi, Chetan S

    2014-01-01

    Proximal humeral fractures are common and although the majority can be managed non-operatively, the optimal treatment of displaced or complex fractures remains controversial. Non-operative treatment is typically selected for minimally displaced fractures where union rates are high and good or excellent outcomes can be expected in approximately 80% of cases. The aims of surgical fixation are to restore articular surface congruency, alignment and the relationship between the tuberosities and the humeral head. Hemiarthroplasty provides patients with reliable pain relief and its indications include fracture dislocations, humeral head splitting fractures and some three- and four- part fractures. The key areas of surgical technique that influence functional outcome include correctly restoring the humeral height, humeral version and tuberosity position. Function, however, is poor if the tuberosities either fail to unite or mal-unite. The interest in reverse shoulder arthroplasty as an alternative option has therefore recently increased, particularly in older patients with poor bone quality and tuberosity comminution. The evidence supporting this, however, is currently limited to multiple case series with higher level studies currently underway. PMID:25067968

  11. Proximity graphs based multi-scale image segmentation

    SciTech Connect

    Skurikhin, Alexei N [Los Alamos National Laboratory

    2008-01-01

    We present a novel multi-scale image segmentation approach based on irregular triangular and polygonal tessellations produced by proximity graphs. Our approach consists of two separate stages: polygonal seeds generation followed by an iterative bottom-up polygon agglomeration into larger chunks. We employ constrained Delaunay triangulation combined with the principles known from the visual perception to extract an initial ,irregular polygonal tessellation of the image. These initial polygons are built upon a triangular mesh composed of irregular sized triangles and their shapes are ad'apted to the image content. We then represent the image as a graph with vertices corresponding to the polygons and edges reflecting polygon relations. The segmentation problem is then formulated as Minimum Spanning Tree extraction. We build a successive fine-to-coarse hierarchy of irregular polygonal grids by an iterative graph contraction constructing Minimum Spanning Tree. The contraction uses local information and merges the polygons bottom-up based on local region-and edge-based characteristics.

  12. Development of procedures for programmable proximity aperture lithography

    NASA Astrophysics Data System (ADS)

    Whitlow, H. J.; Gorelick, S.; Puttaraksa, N.; Napari, M.; Hokkanen, M. J.; Norarat, R.

    2013-07-01

    Programmable proximity aperture lithography (PPAL) with MeV ions has been used in Jyväskylä and Chiang Mai universities for a number of years. Here we describe a number of innovations and procedures that have been incorporated into the LabView-based software. The basic operation involves the coordination of the beam blanker and five motor-actuated translators with high accuracy, close to the minimum step size with proper anti-collision algorithms. By using special approaches, such writing calibration patterns, linearisation of position and careful backlash correction the absolute accuracy of the aperture size and position, can be improved beyond the standard afforded by the repeatability of the translator end-point switches. Another area of consideration has been the fluence control procedures. These involve control of the uniformity of the beam where different approaches for fluence measurement such as simultaneous aperture current and the ion current passing through the aperture using a Faraday cup are used. Microfluidic patterns may contain many elements that make-up mixing sections, reaction chambers, separation columns and fluid reservoirs. To facilitate conception and planning we have implemented a .svg file interpreter, that allows the use of scalable vector graphics files produced by standard drawing software for generation of patterns made up of rectangular elements.

  13. Interactive orbital proximity operations planning system instruction and training guide

    NASA Technical Reports Server (NTRS)

    Grunwald, Arthur J.; Ellis, Stephen R.

    1994-01-01

    This guide instructs users in the operation of a Proximity Operations Planning System. This system uses an interactive graphical method for planning fuel-efficient rendezvous trajectories in the multi-spacecraft environment of the space station and allows the operator to compose a multi-burn transfer trajectory between orbit initial chaser and target trajectories. The available task time (window) of the mission is predetermined and the maneuver is subject to various operational constraints, such as departure, arrival, spatial, plume impingement, and en route passage constraints. The maneuvers are described in terms of the relative motion experienced in a space station centered coordinate system. Both in-orbital plane as well as out-of-orbital plane maneuvering is considered. A number of visual optimization aids are used for assisting the operator in reaching fuel-efficient solutions. These optimization aids are based on the Primer Vector theory. The visual feedback of trajectory shapes, operational constraints, and optimization functions, provided by user-transparent and continuously active background computations, allows the operator to make fast, iterative design changes that rapidly converge to fuel-efficient solutions. The planning tool is an example of operator-assisted optimization of nonlinear cost functions.

  14. Topological proximity effect in a topological insulator hybrid

    NASA Astrophysics Data System (ADS)

    Shoman, T.; Takayama, A.; Sato, T.; Souma, S.; Takahashi, T.; Oguchi, T.; Segawa, Kouji; Ando, Yoichi

    2015-03-01

    It is well known that a topologically protected gapless state appears at an interface between a topological insulator and an ordinary insulator; however, the physics of the interface between a topological insulator and a metal has largely been left unexplored. Here we report a novel phenomenon termed topological proximity effect, which occurs between a metallic ultrathin film and a three-dimensional topological insulator. We study one bilayer of bismuth metal grown on the three-dimensional topological insulator material TlBiSe2, and by using spin- and angle-resolved photoemission spectroscopy, we found evidence that the topological Dirac-cone state migrates from the surface of TlBiSe2 to the attached one-bilayer Bi. We show that such a migration of the topological state occurs as a result of strong spin-dependent hybridization of the wave functions at the interface, which is also supported by our first-principles calculations. This discovery points to a new route to manipulating the topological properties of materials.

  15. Resist toploss and profile modeling for optical proximity correction applications

    NASA Astrophysics Data System (ADS)

    Zuniga, Christian; Deng, Yunfei

    2014-10-01

    As critical dimensions decrease for 32-nm node and beyond, the resist loss increases and resist patterns become more vulnerable to etching failures. Traditional optical proximity correction (OPC) models only consider two-dimensional (XY) contours and neglect height (Z) variations. Rigorous resist simulators can simulate a three-dimensional (3-D) resist profile, but they are not fast enough for correction or verification on a full chip. However, resist loss for positive-tone resists is mainly driven by optical intensity variations, which are accurately modeled by the optical portion of an OPC model. We show that a compact resist model can be used to determine resist loss by properly selecting the optical image plane for calibration. The model can then be used to identify toploss hotspots on a full chip and, in some cases, for correction of these patterns. In addition, the article will show how the model can be made more accurate by accounting for some 3-D effects like diffusion through height.

  16. Proximity effect in superconductor/conical magnet heterostructures

    NASA Astrophysics Data System (ADS)

    Fritsch, D.; Annett, J. F.

    2014-07-01

    The presence of a spin-flip potential at the interface between a superconductor and a ferromagnetic metal allows for the generation of equal-spin spin-triplet Cooper pairs. These Cooper pairs are compatible with the exchange interaction within the ferromagnetic region and hence allow for the long-range proximity effect through a ferromagnet or half-metal. One suitable spin-flip potential is provided by incorporating the conical magnet Holmium (Ho) into the interface. The conical magnetic structure is characterised by an opening angle ? with respect to the crystal c-axis and a turning (or pitch) angle ? measuring the rotation of magnetisation with respect to the adjacent layers. Here, we present results showing the influence of conical magnet interface layers with varying ? and ? on the efficiency of the generation of equal-spin spin-triplet pairing. The results are obtained by self-consistent solutions of the microscopic Bogoliubov-de Gennes equations in the clean limit within a tight-binding model of the heterostructure. In particular, the dependence of unequal-spin and equal-spin spin-triplet pairing correlations on the conical magnetic angles ? and ? are discussed in detail.

  17. Essential genes in proximal 3L heterochromatin of Drosophila melanogaster.

    PubMed

    Schulze, S; Sinclair, D A; Silva, E; Fitzpatrick, K A; Singh, M; Lloyd, V K; Morin, K A; Kim, J; Holm, D G; Kennison, J A; Honda, B M

    2001-02-01

    We have further characterized essential loci within the centric heterochromatin of the left arm of chromosome 3 (3L) of Drosophila melanogaster, using EMS, radiation and P element mutagenesis. We failed to find any new essential genes, a result that suggests a lower-than-average gene density in this region. Mutations affecting expression of the most proximal gene [lethal 1, l1 or l(3)80Fj] act as dominant suppressors of Polycomb (Pc), behavior which is consistent with a putative trithorax group (trx-G) gene. The third gene to the left of the centromere [lethal 3, l3 or l(3)80Fh] is likely to correspond to verthandi (vtd), a known trx-G gene that plays a role in the regulation of hedgehog (hh) expression and signalling. The intervening gene [lethal 2, l2 or l(3)80Fi] is required throughout development, and mutant alleles have interesting phenotypes; in various allelic combinations that survive, we observe fertility, bristle, wing, eye and cuticle defects. PMID:11254125

  18. Distinct afferent innervation patterns within the human proximal and distal esophageal mucosa.

    PubMed

    Woodland, Philip; Aktar, Rubina; Mthunzi, Engelbert; Lee, Chung; Peiris, Madusha; Preston, Sean L; Blackshaw, L Ashley; Sifrim, Daniel

    2015-03-15

    Little is known about the mucosal phenotype of the proximal human esophagus. There is evidence to suggest that the proximal esophagus is more sensitive to chemical and mechanical stimulation compared with the distal. This may have physiological relevance (e.g., in prevention of aspiration of gastroesophageal refluxate), but also pathological relevance (e.g., in reflux perception or dysphagia). Reasons for this increased sensitivity are unclear but may include impairment in mucosal barrier integrity or changes in sensory innervation. We assessed mucosal barrier integrity and afferent nerve distribution in the proximal and distal esophagus of healthy human volunteers. In 10 healthy volunteers baseline proximal and distal esophageal impedance was measured in vivo. Esophageal mucosal biopsies from the distal and proximal esophagus were taken, and baseline transepithelial electrical resistance (TER) was measured in Ussing chambers. Biopsies were examined immunohistochemically for presence and location of calcitonin gene-related peptide (CGRP)-immunoreactive nerve fibers. In a further four healthy volunteers we investigated for colocalization of CGRP and protein gene product (PGP) 9.5 immunoreactivity in nerve fibers. Baseline impedance was higher in the proximal than in the distal esophagus [2,936 ? (SD578) vs. 2,229 ? (SD821); P = 0.03], however, baseline TER was not significantly different between them. Mucosal CGRP-immunoreactive nerves were found in the epithelium of both proximal and distal esophagus, but were located more superficially in the proximal mucosa compared with the distal [11.5 (SD7) vs. 21.7 (SD5) cell layers from lumen, P = 0.002] 19% of proximal, and 10% of distal mucosal PGP-immunoreactive fibers colocalized with CGRP. PGP-immunoreactive fibers were also significantly closer to the luminal surface in the proximal compared with the distal esophagus (P < 0.001). We conclude that mucosal barrier integrity is similar in proximal and distal esophagus, but proximal mucosal afferent nerves are in a more superficial location. The enhanced sensitivity to reflux-evoked symptoms of the proximal esophagus most likely has an anatomical basis. PMID:25573174

  19. Effect of water intake on Na?K-ATPase in nephron segments of the desert rodent, Jaculus orientalis

    Microsoft Academic Search

    A. Doucet; C. Barlet; K. Baddouri

    1987-01-01

    Na-K-ATPase activity was measured in individual pieces of nephron microdissected from collagenase-treated kidneys of jerboas,Jaculus orientalis. Na-K-ATPase activity was high in the distal convoluted tubule, intermediate in the thick ascending limb of the loop of Henle and low in the proximal and collecting tubule. When jerboas were adapted for several weeks to a hydrated diet and excreted a more diluted

  20. NaF Documentation

    Cancer.gov

    The NaF documentation files are presented in Adobe Acrobat or Word files. PDF Generic Documentation for NaF PDF file Word Generic Documentation for NaF Word file Contact G. Craig Hill, Ph.D. for information. Email: hillgc@mail.nih.gov, Phone: 240-276-5913 Print

  1. Evidence for a Na+–H+ Exchange Across Human Colonic Basolateral Plasma Membranes Purified from Organ Donor Colons

    Microsoft Academic Search

    Sangeeta Tyagi; Virendra Joshi; Waddah A. Alrefai; Ravinder K. Gill; Krishnamurthy Ramaswamy; Pradeep K. Dudeja

    2000-01-01

    The mechanism(s) of electrolyte transport across the human colonic contraluminal domain is not well understood. Current studies were undertaken to develop a technique for the isolation and purification of the human colonic basolateral membrane vesicles (BLMV) and to examine the presence of a Na+–H+ exchange process in these membranes. BLMV were purified from mucosal scrapings of organ donor proximal colons

  2. No benefit of a proximal stem centralizer in cementing of a femoral prosthesis in human cadavers

    PubMed Central

    2011-01-01

    Background and purpose A proximal stem centralizer may be beneficial regarding cementing pressures, cement penetration, and stem alignment. We measured these parameters when cementing a mat-surfaced femoral component with and without the use of a proximal stem centralizer. Material and methods 8 femoral prostheses with proximal centralizers and 8 femoral prostheses without proximal centralizers were cemented according to third-generation cementing technique in 8 pairs of embalmed cadaveric femora. We recorded intramedullary pressures (peak levels, the area under the pressure curves and mean pressure) with 6 pressure transducers during stem cementation. Computer tomographic scanning of specimens was performed to evaluate stem alignment after surgery. Thickness of the cement mantle, cement penetration, and stem centralization at the metaphyseal part of the femur were measured on cross sections using stereology. Results There were no statistically significant differences in measured pressure and cement penetration values between the groups. There was similar cement distribution around the stems; however, in using a proximal centralizer, the cement mantle tended to be thinner laterally. Moreover, we found a larger variation in stem alignment on lateral projection in the proximal centralizer group. Interpretation No benefits regarding intramedullary pressures and cement penetration were obtained from cementation of a straight stem with a proximal stem centralizer. However, there was an increased risk of inferior stem positioning in the reamed medullary cavity using the centralizing device. PMID:21434768

  3. Superficial temporal artery to proximal posterior cerebral artery bypass through the anterior temporal approach

    PubMed Central

    Takeuchi, Satoru; Tanikawa, Rokuya; Tsuboi, Toshiyuki; Noda, Kosumo; Oda, Junpei; Miyata, Shiro; Ota, Nakao; Yoshikane, Tsutomu; Kamiyama, Hiroyasu

    2015-01-01

    Background: The superficial temporal artery (STA) to proximal posterior cerebral artery (PCA) (P2 segment) bypass is one of the most difficult procedures to perform because the proximal PCA is located deep and high within the ambient cistern. STA to proximal PCA bypass is usually performed through a subtemporal approach or posterior transpetrosal approach, and rarely through a transsylvian approach. The aim of this study was to describe the operative technique of STA to proximal PCA bypass through a modified transsylvian approach (anterior temporal approach). Methods: STA to proximal PCA bypass was performed through an anterior temporal approach in three patients with intracranial aneurysm. We describe the details of the surgical technique. Results: The STA was successfully anastomosed to the proximal PCA in all cases. One patient suffered hemiparesis and aphasia due to infarction in the anterior thalamoperforating artery territory. Conclusions: STA to proximal PCA bypass can be performed through an anterior temporal approach in selected patients. We recommend that every precaution, including complete hemostasis, placement of cellulose sponges beneath the recipient artery to elevate the site of the anastomosis, and placement of a continuous drainage tube at the bottom of the operative field to avoid blood contamination during the anastomosis, should be taken to shorten the temporary occlusion time.

  4. Self-perceptions of proximal stability as measured by the functional movement screen.

    PubMed

    Palmer, Thomas G; Howell, Dana M; Mattacola, Carl G; Viele, Kert

    2013-08-01

    This mixed method study was designed to investigate self-perceptions before and after experiencing an activity that dynamically and statically challenges proximal stability of the pelvis, spine, and trunk. Twenty-eight, healthy Division II female soccer and volleyball collegiate players (17 soccer, 11 volleyball) completed a self-reported Tegner activity scale, pretest questionnaire and posttest interview. A self-perceived numeric rating of the athletes' proximal stability and performance on a functional movement screen (FMS) were recorded. A guided interview was used to examine the self-perceptions of proximal stability after the FMS testing session. Differences and correlations between the pretest and posttest ratings of proximal stability and FMS scores were analyzed using a 1-sample Kolmogorov-Smirnov test and Spearman's rank order correlation test, respectively. Residual standard error from a 1-way analysis of variance was used to explore the association between variables. Qualitative data were recorded and transcribed. There were significant differences between the pretest (3.4 ± 0.63) and posttest ratings (3.1 ± 0.49) of proximal stability (p = 0.01). The relationship between the pretest proximal stability ratings and the FMS scores was low (r = 0.19, p = 0.33), whereas posttest rating and FMS scores had a moderately high (r = 0.68, p = 0.00) correlation. There was a smaller residual standard error for the posttest ratings (1.7) when compared with the pretest ratings (3.2) with the FMS. Four qualitative themes emerged: (a) wanting to do well, (b) expectations of performance, (c) focused mental mindset, and (d) body control. Self-perceptions of proximal stability in female athletes were influenced by undergoing a test that stressed the proximal stabilizers. Combining assessments of self-perceptions and proximal stability may assist clinicians and athletes in targeting components of training. PMID:23207886

  5. Proximal Ignimbrite Geometry on Santorini, Greece Using Ground Penetrating Radar

    NASA Astrophysics Data System (ADS)

    Stasiuk, M. V.; Russell, J. K.; Hill, G. J.; Druitt, T. H.

    2001-12-01

    Ground penetrating radar (GPR) surveys on Santorini, Greece, are used to constrain the 3-dimensional geometry of the near-surface pyroclastic deposits produced by the 3.6 ka caldera-forming Minoan eruption. Specifically, the results elucidate deposit structures at the south end of the island. More than 2.4 km of radar survey data were collected at a measurement spacing of 0.5-1.0 m, using the common offset reflection method (3 m offset) and radar frequencies of 50 and 100 MHz. Imaging depths of the raw data were typically small (<10 m) due to noise introduced by a local aviation radar facility which was in line-of-sight of most of the field survey. Most noise was removed by the application of standard radar signal processing techniques, allowing imaging to depths of 20-30 m, greater than the typical thickness of the Minoan eruption package. Survey lines were run between deposit exposures to ensure direct correlation between the observed depositional units and the geophysical data. This approach allows characterization of the radar signature of each deposit and facilitates subsurface mapping where exposures are absent. The phase 1 Plinian pumice is defined in the radar profiles as a unit with near constant thickness and little internal structure. The phase 2 surge and phase 3 massive tuff have similar radar propogation properties so the contact is poorly-defined by GPR, but the data reveal the cross-bedded internal structure of the surge allowing it to be mapped. The radar characterizations of the units and their contacts are continuous over the survey area, creating a well-defined image of the eruption package geometry over a 2-km-wide proximal segment of the volcano slope. The results show that the depositional package of airfall, surge deposits, massive tuff and ignimbrite is surprisingly uniform in thickness, except in minor paleo-lows where it thickens. In addition, each unit in the survey area is approximately uniform in thickness. The geometrical uniformity changes near the paleo-coast location, where the depositional package dramatically thickens as it crosses a line of low, coast-parallel paleo-sea cliffs. Observations of the deposits at the current coastline, outboard of the paleo-cliffs, suggest that the increase in thickness is due dominantly to a sudden thickening of the phase 4 pyroclastic flow deposit. This geometry contrasts with previous models, based on interpolation between outcrops. These proposed that the deposits of phases 2 and 3 thin gradually with distance from the caldera rim while phase 4 gradually thickens. The GPR results suggest that the flows were more energetic than the previous model implied, and too energetic to bulk deposit in the subaerial, proximal area. Most of the mass of pyroclastics swept down the slope and into the sea, leaving behind only thin veneers. The velocity reduction caused by a combination of the phase 4 flow thickening as it passed over the ancient sea cliffs, and by entering the sea, caused the flow to switch to a strongly depositional mode resulting in a thickened deposit. An implication of these results is that most of the Minoan pyroclastic flow deposits on Santorini, apart from those near and on the outer coast, were emplaced aggradationally.

  6. Design and characterization of a close-proximity thermoacoustic sensor.

    PubMed

    Xing, Jida; Choi, Michael; Ang, Woon; Yu, Xiaojian; Chen, Jie

    2013-09-01

    Although the radiation force balance is the gold standard for measuring ultrasound intensity, it cannot be used for real-time monitoring in certain settings, for example, bioreactors or in the clinic to measure ultrasound intensities during treatment. Foreseeing these needs, we propose a close-proximity thermoacoustic sensor. In this article, we describe the design, characterization, testing and implementation of such a sensor. We designed a 20-mm-diameter plexiglass sensor with a 2-mm-long absorber and tested it against low-intensity pulsed ultrasound generated at a 1.5-MHz frequency, 20% duty cycle, 1-kHz pulse repetition frequency and intensities between 30 and 120 mW/cm(2). The sensor captures the beam, converts the ultrasound power into heat and indirectly measures the spatial-average time-average ultrasound intensity (Isata) by dividing the calculated power by the beam cross section (or the nominal area of the transducers). A thin copper sheet was attached to the back face of the sensor with thermal paste to increase heat diffusivity 1000-fold, resulting in uniform temperature distribution across the back face. An embedded system design was implemented using an Atmel microcontroller programmed with a least-squares algorithm to fit measured temperature-versus-time data to a model describing the temperature rise averaged across the back side of the sensor in relation to the applied ultrasound intensity. After it was calibrated to the transducer being measured, the thermoacoustic sensor was able to measure ultrasound intensity with an average error of 5.46% compared with readings taken using a radiation force balance. PMID:23820248

  7. Dorsoproximal proximal phalanx osteochondral fragmentation in 117 Warmblood horses.

    PubMed

    Declercq, J; Martens, A; Maes, D; Boussauw, B; Forsyth, R; Boening, K J

    2009-01-01

    The objective of the present study was to determine clinical and arthroscopic characteristics associated with dorsoproximal proximal phalanx (P1) fragments in Warmblood horses, as well as to examine their histopathological appearance. One hundred sixty-eight fragments were removed from 150 fetlocks of 117 Warmblood horses. Details of signalment and results of clinical examination were collected prior to surgery. After arthroscopic fragment removal and joint evaluation for synovial and/or cartilage abnormalities, the fragments were measured and evaluated histopathologically. The vast majority of the fragments (95.2%) were found medially, without predilection for front or hind limbs. In 10% of the joints, more than one fragment was present. The mean size of the fragments was 6.8 +/- 2.6 mm. Only eight horses presented fetlock-related lameness. Horses of seven years of age and older (OR = 13.32; p = 0.033) and the presence of more than one fragment (OR = 11.12; p = 0.016) were significantly associated with lameness. Arthroscopic evaluation revealed one or more abnormalities in 50.7% of the joints. On histopathology, osteochondral fragments presented as a bony center covered with smooth hyaline cartilage on one side and some fibrous tissue on the other side. No clear histopathological signs were indicating precisely their origin. In Warmblood horses with dorsoproximal P1 fragments, the age (seven years and older) and the presence of more than one fragment in a fetlock significantly increased the risk of lameness. The osteochondral dorsoproximal P1 fragments could be defined as a developmental orthopaedic disease. PMID:19151863

  8. Anomalous magnetic properties and proximity effect coupling in VAMAS strands

    NASA Astrophysics Data System (ADS)

    Sumption, M. D.; Collings, E. W.

    Anomalously low levels of proximity effect (PE) coupling, as well as an anomalously high paramagnetic tilt, have been found in some of the superconducting multifilamentary strands produced for the Versailles Project on Advanced Materials and Standards (VAMAS). We report on two types of strands that were measured for the 2nd VAMAS intercomparison program on low-frequency (hysteretic) AC loss: (i) a Cu matrix (H-) series with filament diameters ( df) ranging from 0.5 ?m to 12 ?m and (ii) a nominal Cu-10 wt% Ni (l-) series with df ranging from 0.4 ?m to 1 ?m. The l-series strands combine anomalously low levels of PE coupling with a strong paramagnetic tilt. Microprobe analysis of the matrix alloy revealed a composition of 10.3 wt% Ni plus 0.78 wt% Mn, which is in agreement with the manufacturer's specification sheets. The paramagnetic tilt can be shown to be due almost entirely to the presence of the Mn which also plays a dominant role in the anomalous PE suppression. The presence of Mn in this nominally Cu-Ni matrix resolves the 'anomalously' low coupling and magnetic properties of the l-series strands in a straightforward way. On the other hand, manufacturer's specifications and microprobe analysis showed that the matrix for the H-series strands was pure Cu. These strands also exhibited an anomalously low level of PE coupling but for different reasons, to be discussed. The PE coupling of these strands is compared to those with a variety of other matrices, while attempting to correct for non-matrix-material factors.

  9. Does Proximity Matter? Distance Dependence of Adolescent Friendships

    PubMed Central

    Preciado, Paulina; Snijders, Tom A.B.; Burk, William J.; Stattin, Håkan; Kerr, Margaret

    2014-01-01

    Geographic proximity is a determinant factor of friendship. Friendship datasets that include detailed geographic information are scarce, and when this information is available, the dependence of friendship on distance is often modelled by pre-specified parametric functions or derived from theory without further empirical assessment. This paper aims to give a detailed representation of the association between distance and the likelihood of friendship existence and friendship dynamics, and how this is modified by a few basic social and individual factors. The data employed is a three-wave network of 336 adolescents living in a small Swedish town, for whom information has been collected on their household locations. The analysis is a three-step process that combines 1) nonparametric logistic regressions to unravel the overall functional form of the dependence of friendship on distance, without assuming it has a particular strength or shape; 2) parametric logistic regressions to construct suitable transformations of distance that can be employed in 3) stochastic models for longitudinal network data, to assess how distance, individual covariates, and network structure shape adolescent friendship dynamics. It was found that the log-odds of friendship existence and friendship dynamics decrease smoothly with the logarithm of distance. For adolescents in different schools the dependence is linear, and stronger than for adolescents in the same school. Living nearby accounts, in this dataset, for an aspect of friendship dynamics that is not explicitly modelled by network structure or by individual covariates. In particular, the estimated distance effect is not correlated with reciprocity or transitivity effects. PMID:25530664

  10. Hybrid magnetoresistance in the proximity of a ferromagnet

    NASA Astrophysics Data System (ADS)

    Chien, Chia-Ling

    2014-03-01

    A new type of magnetoresistance (MR) effect has recently been observed in nominally nonmagnetic metal (Pt) thin films in contact with either a ferromagnetic (FM) insulator such as yttrium iron garnet (YIG), or a FM metal, such as permalloy (Py). The resistivities with in-plane magnetic fields parallel (??) and transverse (?T) to a current and a perpendicular field (??) at room temperature show the behavior of ?? ~?? >?T, distinctively different from all other known MR effects, including the well-known anisotropic MR in FMs of ??>?T ~?? . The key question is whether the new MR is the proposed spin Hall MR (SMR) based on spin current conversion in Pt, or due to magnetic proximity effects (MPE), for which Pt is highly susceptible when in contact with a FM. Recent experiments show that the characteristics of ?? ~?? >?T, for which the SMR theory accounts, do not hold at low temperatures nor at different magnetic fields. Furthermore, the new MR persists even after altering the Pt/YIG interface thereby blocking the spin current. The feature of new MR can also be reproduced when Pt is in contact with a non-magnetic insulator doped with a few percent of Fe impurities. These results show that the new MR is probably due to both spin current and MPE. Through tuning the YIG surface and the insertion of other layers between Pt and YIG, we are able to separate the two contributions of spin current and MPE of the new hybrid MR. This work, in collaboration with S. Y. Huang, D. Qu (JHU) B. F. Miao (JHU and Nanjing University), Y. M. Lu and J. W. Cai (Institute of Physics, Chinese Academy of Sciences), has been supported in part by NSF DMR1262253. H. Nakayama et al.,Phys. Rev. Lett. 110, 206601(2013).

  11. Disruption of the proximal tibiofibular joint in the setting of multi-ligament knee injury.

    PubMed

    Porrino, Jack A

    2015-08-01

    Instability of the proximal tibiofibular joint is a relatively uncommon condition when in isolation; however, instability of the proximal tibiofibular joint is far more frequent in those presenting with a severe multi-ligament injury of the knee. If this joint is left unstable, repair of a co-existent injury of the posterolateral corner may fail, regardless of the proficiency of the technique. We present two patients with disruption of the proximal tibiofibular joint, including the MRI appearance, who initially presented to our hospital for management of significant polytrauma, as well as multi-ligament injury of the ipsilateral knee. PMID:25750062

  12. Light chain proximal tubulopathy with cast nephropathy in a case of multiple myeloma.

    PubMed

    Gowda, K K; Joshi, K; Nada, R; Ramachandran, R; Sachdeva, M

    2015-01-01

    The renal diseases most frequently associated with myeloma include cast nephropathy (CN), amyloidosis and monoclonal immunoglobulin deposition disease. Light chain proximal tubulopathy (LCPT) is reported less frequently. Majority of the cases with ?-restriction present with Fanconi syndrome (FS) and show crystals in proximal tubular epithelial cytoplasm. In contrast, those with ?-restriction are infrequently associated with FS and show cytoplasmic vacuolations in proximal tubular epithelial cytoplasm. Combination of morphologies in kidney affected by plasma cell dyscrasias is rare and co-existence of LCPT and CN is one of the rarest. We report a case of multiple myeloma having this rare combination of morphologies. PMID:25838654

  13. Tibial rotational osteotomy for idiopathic torsion. A comparison of the proximal and distal osteotomy levels.

    PubMed

    Krengel, W F; Staheli, L T

    1992-10-01

    A retrospective analysis was done of 52 rotational tibial osteotomies (RTOs) performed on 35 patients with severe idiopathic tibial torsion. Thirty-nine osteotomies were performed at the proximal or midtibial level. Thirteen were performed at the distal tibial level with a technique previously described by one of the authors. Serious complications occurred in five (13%) of the proximal and in none of the distal RTOs. For severe and persisting idiopathic tibial torsion, the authors recommend correction by RTO at the distal level. Proximal level osteotomy is indicated only when a varus or valgus deformity required concurrent correction. PMID:1395261

  14. Foreign direct investment, intra-organizational proximity, and technological capability : the case of China's automobile industry

    E-print Network

    Nam, Kyung-min

    2010-01-01

    This dissertation consists of three self-contained essays, each of which examines part of the causal link among inward/outward foreign direct investment (FDI), intra-organizational proximity, and in-house technology ...

  15. Osteoporotic fractures of the proximal humerus, pelvis, and ankle: epidemiology and diagnosis.

    PubMed

    Guggenbuhl, Pascal; Meadeb, Jean; Chalès, Gérard

    2005-10-01

    Although fractures involving the wrist, spine, and proximal femur are known to be strongly associated with osteoporosis, the underlying bone insufficiency often receives insufficient diagnostic and therapeutic attention. Osteoporosis also increases the risk of fractures at other sites. Low-energy fractures in patients older than 50 years should lead to investigations for osteoporosis, the only exceptions being fractures of the skull, cervical spine, fingers, and toes. The incidence rates of fractures of the proximal humerus, pelvis, and ankle are climbing relentlessly. Whereas fractures of the proximal humerus and pelvis are undoubtedly related to osteoporosis, the link is less well established for fractures of the ankle. Mortality and morbidity rates associated with pelvic fractures are similar to those seen with fractures of the proximal femur, in keeping with the fact that both fractures occur in elderly individuals. PMID:16214070

  16. Social Service Availability & Proximity And The Over-Representation Of Minority Children in Child Welfare 

    E-print Network

    Bathman, Jake; Foster, David; Ingels, Laura; Lee, Chongmyoung; Miramontes, Claudia; Youngblood, Jo

    2010-01-01

    The capstone group assessed whether child welfare services were available and proximal in predominantly low income, black areas with high foster care rates in three southern cities. GIS mapping of services contained in a State 211 community services...

  17. Locked vs. unlocked plate osteosynthesis of the proximal humerus – A biomechanical study

    Microsoft Academic Search

    K. Seide; J. Triebe; M. Faschingbauer; A. P. Schulz; K. Püschel; G. Mehrtens; Ch. Jürgens

    2007-01-01

    BackgroundLocked plates (internal fixators) have been found to be an optimal method for the fixation in proximal humeral fractures. In a biomechanical cadaver study the difference between locked and non-locked osteosyntheses was investigated.

  18. Proximity Effect - Amorphous Sn-Fe, Amorphous Bi-Fe Films 

    E-print Network

    CORT, G.; Naugle, Donald G.

    1981-01-01

    . Hauser et al. ' and Kircher' have demonstrated this for gadolinium, iron, and nickel normal layers. Hauser er al. ' (HTW) have extended the de Gennes-Werthamer theory of proximity effects" to include sandwiches with ferromagnetic normal-metal layers...

  19. Magnetic proximity effect and interlayer exchange coupling of ferromagnetic/topological insulator/ferromagnetic trilayer

    E-print Network

    Li, Mingda

    The magnetic proximity effect between the topological insulator (TI) and ferromagnetic insulator (FMI) is considered to have great potential in spintronics. However, a complete determination of interfacial magnetic structure ...

  20. Methods and modeling for the reduced platen compression of cancellous bone in the rodent proximal tibia

    E-print Network

    Rogers, William Elliott

    2002-01-01

    This study focused on the reduced platen compression (RPC) test of cancellous bone in the rodent proximal tibia. The objective was to improve methods for this mechanical test, specifically in the areas of specimen location, specimen preparation...

  1. Management bone loss of the proximal femur in revision hip arthroplasty: Update on reconstructive options

    PubMed Central

    Sakellariou, Vasileios I; Babis, George C

    2014-01-01

    The number of revision total hip arthroplasties is expected to rise as the indications for arthroplasty will expand due to the aging population. The prevalence of extensive proximal femoral bone loss is expected to increase subsequently. The etiology of bone loss from the proximal femur after total hip arthroplasty is multifactorial. Stress shielding, massive osteolysis, extensive loosening and history of multiple surgeries consist the most common etiologies. Reconstruction of extensive bone loss of the proximal femur during a revision hip arthroplasty is a major challenge for even the most experienced orthopaedic surgeon. The amount of femoral bone loss and the bone quality of the remaining metaphyseal and diaphyseal bone dictate the selection of appropriate reconstructive option. These include the use of impaction allografting, distal press-fit fixation, allograft-prosthesis composites and tumor megaprostheses. This review article is a concise review of the current literature and provides an algorithmic approach for reconstruction of different types of proximal femoral bone defects. PMID:25405090

  2. Algorithm for the calculation of proximity area and area centroid within the carpal joint

    E-print Network

    Boyd, Nolan Lee

    1998-01-01

    -dimensional model, and each bone shape examined for gross flaws. Proximity distances were calculated for each discrete point of the bone surface. An algorithm was written in C which used the discrete spatial locations of the bone surfaces, each location...

  3. Interindividual variability in social insects - proximate causes and ultimate consequences.

    PubMed

    Jeanson, Raphaël; Weidenmüller, Anja

    2014-08-01

    Individuals within social groups often show consistent differences in behaviour across time and context. Such interindividual differences and the evolutionary challenge they present have recently generated considerable interest. Social insects provide some of the most familiar and spectacular examples of social groups with large interindividual differences. Investigating these within-group differences has a long research tradition, and behavioural variability among the workers of a colony is increasingly regarded as fundamental for a key feature of social insects: division of labour. The goal of this review is to illustrate what we know about both the proximate mechanisms underlying behavioural variability among the workers of a colony and its ultimate consequences; and to highlight the many open questions in this research field. We begin by reviewing the literature on mechanisms that potentially introduce, maintain, and adjust the behavioural differentiation among workers. We highlight the fact that so far, most studies have focused on behavioural variability based on genetic variability, provided by e.g. multiple mating of the queen, while other mechanisms that may be responsible for the behavioural differentiation among workers have been largely neglected. These include maturational, nutritional and environmental influences. We further discuss how feedback provided by the social environment and learning and experience of adult workers provides potent and little-explored sources of differentiation. In a second part, we address what is known about the potential benefits and costs of increased behavioural variability within the workers of a colony. We argue that all studies documenting a benefit of variability so far have done so by manipulating genetic variability, and that a direct test of the effect of behavioural variability on colony productivity has yet to be provided. We emphasize that the costs associated with interindividual variability have been largely overlooked, and that a better knowledge of the cost/benefit balance of behavioural variability is crucial for our understanding of the evolution of the mechanisms underlying the social organization of insect societies. We conclude by highlighting what we believe to be promising but little-explored avenues for future research on how within-colony variability has evolved and is maintained. We emphasize the need for comparative studies and point out that, so far, most studies on interindividual variability have focused on variability in individual response thresholds, while the significance of variability in other parameters of individual response, such as probability and intensity of the response, has been largely overlooked. We propose that these parameters have important consequences for the colony response. Much more research is needed to understand if and how interindividual variability is modulated in order to benefit division of labour, homeostasis and ultimately colony fitness in social insects. PMID:24341677

  4. An oreopithecid proximal humerus from the middle miocene of Maboko Island, Kenya

    Microsoft Academic Search

    Monte L. McCrossin

    1992-01-01

    A proximal humerus, recently recovered from the middle Miocene of Maboko Island, Kenya, provides the earliest evidence of\\u000a postcranial structure and adaptation of Oreopithecidae. Provisionally attributed toNyanzapithecus pickfordi (Harrison, 1986), the specimen manifests a globose head, subequally large tuberosities, and a board, shallow bicipital groove.\\u000a Although readily distinguished from the fundamentally cercopithecoid proximal humeral morphology ofVictoriapithecus (Senut, 1986), the Maboko

  5. HK-2: An immortalized proximal tubule epithelial cell line from normal adult human kidney

    Microsoft Academic Search

    Michael J Ryan; Gretchen Johnson; Judy Kirk; Sally M Fuerstenberg; Richard A Zager; Beverly Torok-Storb

    1994-01-01

    HK-2: An immortalized proximal tubule epithelial cell line from normal adult human kidney. Studies assessing mechanisms of proximal tubular cell (PTC) physiology and pathophysiology increasingly utilize cell culture systems to avoid the complexity of whole organ\\/whole animal experiments. However, no well-differentiated PTC line derived from adult human kidney currently exists. Therefore, the goal of this research was to establish such

  6. Regulation of proximal tubule vacuolar H+-ATPase by PKA and AMP-activated protein kinase

    PubMed Central

    Al-bataineh, Mohammad M.; Gong, Fan; Marciszyn, Allison L.; Myerburg, Michael M.

    2014-01-01

    The vacuolar H+-ATPase (V-ATPase) mediates ATP-driven H+ transport across membranes. This pump is present at the apical membrane of kidney proximal tubule cells and intercalated cells. Defects in the V-ATPase and in proximal tubule function can cause renal tubular acidosis. We examined the role of protein kinase A (PKA) and AMP-activated protein kinase (AMPK) in the regulation of the V-ATPase in the proximal tubule as these two kinases coregulate the V-ATPase in the collecting duct. As the proximal tubule V-ATPases have different subunit compositions from other nephron segments, we postulated that V-ATPase regulation in the proximal tubule could differ from other kidney tubule segments. Immunofluorescence labeling of rat ex vivo kidney slices revealed that the V-ATPase was present in the proximal tubule both at the apical pole, colocalizing with the brush-border marker wheat germ agglutinin, and in the cytosol when slices were incubated in buffer alone. When slices were incubated with a cAMP analog and a phosphodiesterase inhibitor, the V-ATPase accumulated at the apical pole of S3 segment cells. These PKA activators also increased V-ATPase apical membrane expression as well as the rate of V-ATPase-dependent extracellular acidification in S3 cell monolayers relative to untreated cells. However, the AMPK activator AICAR decreased PKA-induced V-ATPase apical accumulation in proximal tubules of kidney slices and decreased V-ATPase activity in S3 cell monolayers. Our results suggest that in proximal tubule the V-ATPase subcellular localization and activity are acutely coregulated via PKA downstream of hormonal signals and via AMPK downstream of metabolic stress. PMID:24553431

  7. Endoreduplication preferentially occurs at the proximal side of the abscission zone during abscission of tomato leaf.

    PubMed

    Dermastia, Marina; Kladnik, Aleš; Bar-Dror, Tal; Lers, Amnon

    2012-09-01

    Endoreduplication is a cell cycle variant in which multiple rounds of DNA replication occur without subsequent mitosis, resulting in polyploid cells. Although cells with endoreduplicated nuclei were ubiquitously distributed throughout the abscission zone (AZ) of tomato leaf before abscission induction by ethylene, endoreduplication was detected mostly on the proximal side of the AZ after induction. The possible association between endoreduplication and intensive membrane trafficking in cells at the proximal side of the AZ is discussed. PMID:22899068

  8. Cubilin- and megalin-mediated uptake of albumin in cultured proximal tubule cells of opossum kidney

    Microsoft Academic Search

    Xiao Yue Zhai; Rikke Nielsen; Henrik Birn; Karina Drumm; Sigrid Mildenberger; Ruth Freudinger; Soren K. Moestrup; Pierre J. Verroust; Erik I. Christensen; Michael Gekle

    2000-01-01

    Cubilin- and megalin-mediated uptake of albumin in cultured proximal tubule cells of opossum kidney.BackgroundReabsorption of albumin from the glomerular filtrate occurs via receptor-mediated endocytosis in the proximal tubule. This process is initiated by binding of albumin in apical clathrin-coated pits, followed by endocytosis and degradation in lysosomes. Although binding sites have been characterized by kinetic studies, the receptors responsible for

  9. Implementation of inductive proximity sensor using nanoporous anodic aluminum oxide layer

    Microsoft Academic Search

    Pei-Hsuan Lo; Chitsung Hong; Sung-Cheng Lo; Weileun Fang

    2011-01-01

    This study presents an inductive proximity sensor implemented through the integration of nano-texture metal-spiral and np-AAO (anodic aluminum oxide (AAO) with nanopores) insulation layer on Si-substrate. The advantages of such nano-structure inductive proximity sensor are as follows, (1) The surface area of nano-texture metal-spiral is increased. Thus, the performance of inductive sensor is increased; and (2) The nano-texture metal-spiral consists

  10. A simple method for proximal anastomoses marking during CABG for future coronary angiography.

    PubMed

    Shani, Liran; Kerner, Arthur; Bolotin, Gil

    2015-07-01

    Evaluation of aortic proximal anastomoses in patients who have undergone coronary artery bypass surgery poses a special challenge to the interventional cardiologist during follow-up angiography procedures. We present a simple, safe, and fast technique for proximal anastomoses marking using hemostatic clips. Successful visualization of the graft marker was achieved using medium-sized hemoclips during fluoroscopy. The use of hemoclips for this procedure proved to be straightforward and required no additional surgical training. PMID:25746426

  11. Long-axis rotation: The missing link in proximal-to-distal segmental sequencing

    Microsoft Academic Search

    R. N. Marshall; B. C. Elliott

    2000-01-01

    Most assessments of segmental sequencing in throwing, striking or kicking have indicated a proximal-to-distal sequencing of end-point linear speeds, joint angular velocities, segment angular velocities and resultant joint moments. However, the role of long-axis rotations has not been adequately quantified and located in the proximal-to-distal sequence. The timing and importance of pronation-supination in the development of racquet head speed have

  12. Fluid secretion in isolated proximal straight renal tubules. Effect of human uremic serum.

    PubMed

    Grantham, J J; Irwin, R L; Qualizza, P B; Tucker, D R; Whittier, F C

    1973-10-01

    We have examined the effect of normal and uremic human sera on the transtubular flow of fluid in isolated perfused segments of rabbit proximal convoluted and straight renal tubules. Proximal convoluted and straight tubules absorbed fluid from the lumen when the external bath was normal rabbit serum. Normal human sera in the bath depressed net fluid absorption in both tubular segments, but more importantly, uremic human serum caused proximal straight tubules to secrete fluid into the lumen. Fluid secretion was also demonstrated indirectly by observing in nonperfused proximal straight, but not proximal convoluted tubules, that the normally collapsed lumens opened widely in uremic serum. Nonperfused proximal straight tubules developed expanded lumens even after a 25-fold dilution of human uremic serum with normal rabbit serum, whereas lumen expansion occurred only in undiluted normal human serum, on the average. Serum from acutely uremic rabbits possessed secretory activity but normal rabbit serum did not. The secretory effect of uremic sera in proximal straight tubules was inhibited by cooling and ouabain and probenecid. The secretory activity of uremic sera was removed by dialysis, but not by freezing or boiling. Para-aminohippurate and benzoate caused fluid secretion in proximal straight tubules but urea, creatinine, guanidinosuccinate, and urate did not. On the basis of these results, we suggest that the secretory factor in serum may be a substance or group of substances possibly related to the hippurate class of organic molecules that are accumulated to relatively high concentrations in renal failure. The secretory material in the serum of uremic patients may significantly influence the transport of salt and water in relatively intact residual nephrons. PMID:4738063

  13. Dominantly inherited proximal myotonic myopathy and leukoencephalopathy in a family with an incidental CLCN1 mutation

    PubMed Central

    Mastaglia, F; Harker, N; Phillips, B; Day, T; Hankey, G; Laing, N; Fabian, V; Kakulas, B

    1998-01-01

    A two generation family of Greek origin with mild myotonia, predominantly proximal muscle weakness, and cataracts compatible with the syndrome of proximal myotonic myopathy, is reported. In addition, brain MRI showed a diffuse leukoencephalopathy in the propositus. Molecular genetic studies showed the R894X mutation in exon 23 of the muscle chloride channel gene in the propositus but in only one of her two clinically affected offspring, indicating that it is not the mutation causing disease in this family.?? PMID:9576553

  14. THE ROLE OF THE MEMBRANE PROXIMAL REGION OF THE M2 CYTOPLASMIC TAIL IN VIRUS REPLICATION

    Microsoft Academic Search

    Shaun Stewart

    2011-01-01

    Influenza A virus encodes M2, a proton channel that has been shown to be important during virus entry and assembly. The primary aim of this thesis was to investigate the role of the membrane proximal region, residues 46-69, of the M2 cytoplasmic tail during virus replication. A cholesterol recognition\\/interaction amino consensus (CRAC) motif, previously identified in the membrane proximal region

  15. Does Geographic Proximity Matter? Evidence from Clustered and Non-clustered Aeronautic Firms in Germany

    Microsoft Academic Search

    Alf Erko Lublinski

    2003-01-01

    L UBLINSKI A. E. (2003) Does geographic proximity matter? Evidence from clustered and non-clustered aeronautic firms in Germany, Reg. Studies 37 , 453-467. This paper analyses what types of inter-firm linkages are stronger between geographically proximate firms compared to distant firms. It compares survey results of clustered and dispersed firms in the German aeronautic (supplying) industry. Results show that geographic

  16. Improving Precision of Proximity Ligation Assay by Amplified Single Molecule Detection

    PubMed Central

    Fredriksson, Simon; Landegren, Ulf; Nilsson, Mats

    2013-01-01

    Proximity ligation assay (PLA) has been proven to be a robust protein detection method. The technique is characterized by high sensitivity and specificity, but the assay precision is probably limited by the PCR readout. To investigate this potential limitation and to improve precision, we developed a digital proximity ligation assay for protein measurement in fluids based on amplified single molecule detection. The assay showed significant improvements in precision, and thereby also detection sensitivity, over the conventional real-time PCR readout. PMID:23874999

  17. The C5a receptor is expressed by human renal proximal tubular epithelial cells

    PubMed Central

    Zahedi, R; Braun, M; Wetsel, R A; Ault, B H; Khan, A; Welch, T R; Frenzke, M; Davis, A E

    2000-01-01

    The C5a receptor is expressed by a variety of cell types. These studies demonstrate by immunohistochemistry that the receptor is present on the surface of proximal and distal tubular epithelial cells from normal kidney. In addition, the receptor was detected on transitional epithelial cells of the ureter and bladder. Primary proximal tubular cultures and a proximal tubular cell line both also expressed the C5a receptor, as demonstrated by immunofluorescence and by FACS analysis. The presence of mRNA encoding the receptor was confirmed by reverse transcriptase-polymerase chain reaction analysis. As opposed to its effect on glomerular mesangial cells, the receptor did not mediate a proliferative response by the proximal tubular cells. C5a also did not enhance the synthesis/secretion of transforming growth factor-beta 1, monocyte chemoattractant protein-1, platelet-derived growth factor-AB or tumour necrosis factor-alpha by cultured proximal tubular cells. Therefore, although the C5a receptor clearly is expressed by proximal tubular cells, clarification of its functional relevance on this cell type awaits further studies. PMID:10931135

  18. Blood flow changes to the proximal femur during total hip arthroplasty

    PubMed Central

    Hupel, Thomas M.; Schemitsch, Emil H.; Aksenov, Sergei A.; Waddell, James P.

    2000-01-01

    Objective To determine the changes in perfusion to the proximal femur that occur during cemented and uncemented total hip arthroplasty (THA). Design Case series. Setting A single tertiary-care centre. Patients Twenty-two consecutive patients. Those who had undergone previous hip surgery or received systemic corticosteroid therapy were excluded. Intervention Cemented (11 procedures) or uncemented (12 procedures) THA. Main outcome measure Changes in blood flow at the level of the proximal femur, measured with laser Doppler flowmetry at 4 different times during THA. Results In both the cemented and the uncemented procedure overall proximal femoral blood flow was reduced (p = 0.002, p = 0.008, respectively). A greater reduction in overall proximal femoral perfusion was seen in the cemented group compared with the uncemented group (p = 0.004). This greater reduction in perfusion was seen primarily in the proximal femoral diaphysis (p = 0.004). Conclusion The extensive canal preparation involved with the cemented procedure or the introduction of bone cement under pressure into the femoral canal may contribute to the greater reduction in perfusion to the proximal femur. PMID:11045094

  19. Responses of proximal tubular cells to injury in congenital renal disease: fight or flight.

    PubMed

    Chevalier, Robert L; Forbes, Michael S; Galarreta, Carolina I; Thornhill, Barbara A

    2014-04-01

    Most chronic kidney disease in children results from congenital or inherited disorders, which can be studied in mouse models. Following 2 weeks of unilateral ureteral obstruction (UUO) in the adult mouse, nephron loss is due to proximal tubular mitochondrial injury and cell death. In neonatal mice, proximal tubular cell death is delayed beyond 2 weeks of complete UUO, and release of partial UUO allows remodeling of remaining nephrons. Progressive cyst expansion develops in polycystic kidney disease (PKD), a common inherited renal disorder. The polycystic kidney and fibrosis (pcy)-mutant mouse (which develops late-onset PKD) develops thinning of the glomerulotubular junction in parallel with growth of cysts in adulthood. Renal insufficiency in nephropathic cystinosis, a rare inherited renal disorder, results from progressive tubular cystine accumulation. In the Ctns knockout mouse (a model of cystinosis), proximal tubular cells become flattened, with loss of mitochondria and thickening of tubular basement membrane. In each model, persistent obstructive or metabolic stress leads ultimately to the formation of atubular glomeruli. The initial "fight" response (proximal tubular survival) switches to a "flight" response (proximal tubular cell death) with ongoing oxidative injury and mitochondrial damage. Therapies should be directed at reducing proximal tubular mitochondrial oxidative injury to enhance repair and regeneration. PMID:23949631

  20. Proximity-induced superconductivity in crystalline Cu and Co nanowires and nanogranular Co structures

    NASA Astrophysics Data System (ADS)

    Kompaniiets, M.; Dobrovolskiy, O. V.; Neetzel, C.; Begun, E.; Porrati, F.; Ensinger, W.; Huth, M.

    2014-08-01

    We report an experimental study of proximity effect-induced superconductivity in crystalline Cu and Co nanowires and a nanogranular Co nanowire structure in contact with a superconducting W-based floating electrode (inducer). For electrical resistance measurements up to three pairs of Pt-based voltage leads were attached at different distances beside the inner inducer electrode, thus allowing us to probe the proximity effect over a length of 2-12 ?m. Up to 30% resistance drops with respect to the normal-state value have been observed for the crystalline Co and Cu nanowires when sweeping the temperature below Tc of the inducer (5.2 K). By contrast, relative R(T) drops were found to be an order of magnitude smaller for the nanogranular Co nanowire structure. Our analysis of the resistance data shows that the superconducting proximity length in crystalline Cu and Co is about 1 ?m at 2.4 K, attesting to a long-range proximity effect in the Co nanowire. Moreover, this long-range proximity effect is insusceptible to magnetic fields up to 11 T, which is indicative of spin-triplet pairing. At the same time, proximity-induced superconductivity in the nanogranular Co nanowire is strongly suppressed due to the dominating Cooper pair scattering caused by its intrinsic microstructure.

  1. Functional role of bicarbonate in propionate transport across guinea-pig isolated caecum and proximal colon.

    PubMed Central

    von Engelhardt, W; Gros, G; Burmester, M; Hansen, K; Becker, G; Rechkemmer, G

    1994-01-01

    1. Unidirectional fluxes of propionate across isolated epithelia from the guinea-pig caecum and proximal colon were measured under short-circuit current conditions. In the caecum and proximal colon the serosal-to-mucosal propionate flux (JPrsm) was higher than mucosal-to-serosal flux (JPrms), resulting in a net secretory flux of propionate. 2. HCO3(-)-CO2-free solution reduced JPrms in the caecum and proximal colon markedly; JPrsm was not (caecum) or little (proximal colon) affected. The subsequent addition of acetazolamide caused a further decrease in JPrms in the proximal colon, but not in the caecum. 3. In HCO3(-)-containing solutions acetazolamide or ethoxzolamide inhibited JPrms; JPrsm was not affected. A macromolecular carbonic anhydrase inhibitor, prontosil-dextran, had no effect on propionate fluxes, indicating that the intracellular carbonic anhydrase is of importance for short-chain fatty acid transport. 4. Subsequent to carbonic anhydrase inhibition, mucosal addition of amiloride caused a slight further decrease of JPrms in the caecum and proximal colon; JPrsm was not affected. 5. Results support the view that a considerable proportion of short-chain fatty acids (SCFAs) is absorbed via a SCFA(-)-HCO3- exchange. PMID:7523661

  2. Na +\\/H + antiporters

    Microsoft Academic Search

    Etana Padan; Miro Venturi; Yoram Gerchman; Nir Dover

    2001-01-01

    Na+\\/H+ antiporters are membrane proteins that play a major role in pH and Na+ homeostasis of cells throughout the biological kingdom, from bacteria to humans and higher plants. The emerging genomic sequence projects already have started to reveal that the Na+\\/H+ antiporters cluster in several families. Structure and function studies of a purified antiporter protein have as yet been conducted

  3. Dual-Mode Capacitive Proximity Sensor for Robot Application: Implementation of Tactile and Proximity Sensing Capability on a Single Polymer Platform Using Shared Electrodes

    Microsoft Academic Search

    Hyung-Kew Lee; Sun-Il Chang; Euisik Yoon

    2009-01-01

    In this paper, we report a flexible dual-mode capacitive sensor for robot applications which has two sensing capabilities in a single platform; tactile and proximity sensing capability. The sensor consists of a mechanical structure based on PDMS (Polydimethylsiloxane) and a mesh of multiple copper electrode strips. The mesh is composed of 16 top and 16 bottom copper strips crossed each

  4. C-Peptide stimulates Na + ,K + ATPase activity via PKC alpha in rat medullary thick ascending limb

    Microsoft Academic Search

    M. Tsimaratos; F. Roger; D. Chabardès; D. Mordasini; U. Hasler; A. Doucet; P.-Y. Martin; E. Féraille

    2003-01-01

      \\u000a \\u000a Aims\\/hypothesis. C-peptide, the cleavage product of proinsulin processing exerts physiological effects including stimulation of Na+,K+-ATPase in erythrocytes and renal proximal tubules. This study was undertaken to assess the physiological effects of connecting\\u000a peptide on Na+,K+-ATPase activity in the medullary thick ascending limb of Henle's loop.\\u000a \\u000a \\u000a \\u000a \\u000a Methods. Na+,K+-ATPase activity was measured as the ouabain-sensitive generation of 32Pi from ?[32P]-ATP and

  5. The water method significantly enhances proximal diminutive adenoma detection rate in unsedated patients

    PubMed Central

    Leung, Joseph W; Siao-Salera, Rodelei M; Mann, Surinder K

    2011-01-01

    Background Colonoscopy has been reported to fail to prevent some post screening colonoscopy incident cancers or minimize cancer mortality in the proximal colon. These reports question the effectiveness of colonoscopy in detecting all proximal adenomas. Diminutive ones which can be obscured by residual feces are particularly at risk. The water method provides salvage cleansing of sub-optimal preparations. Objective To test the hypothesis that the water method enhances proximal diminutive adenoma detection rate (ADR). Design The data bases of two parallel RCT were combined and analyzed. Setting Two Veterans Affairs endoscopy units. Patient and Methods The water and air methods were compared in these two parallel RCT examining unsedated patients. Main Outcome Measurements The combined data on diminutive and overall ADR in the proximal colon, overall ADR, cecal intubation rate, withdrawal time and global bowel cleanliness score. Results Data in the water (n=92) and the air (n=90) groups were assessed. The water method yielded a significantly higher proximal diminutive ADR, 28.3% vs. 14.4% (p=0.0298); cecal intubation rate, 99% vs. 90% (p=0.0091); mean withdrawal time 19 (10) vs. 15 (8) min (p=0.0065) and mean global bowel cleanliness score during withdrawal, 2.6 (0.7) vs. 2.3 (0.6) (p=0.0032). Increase in proximal overall ADR in the water group approached significance, 29.3% vs. 16.7% (p=0.0592). Limitation Small number of predominantly male veterans. Conclusion The significantly higher cecal intubation rate, longer mean withdrawal time and better mean global bowel cleanliness score favor the outcome of significantly enhanced proximal diminutive ADR in the water group. PMID:21686106

  6. Proximity Effect among Cellulose-Degrading Enzymes Displayed on the Saccharomyces cerevisiae Cell Surface

    PubMed Central

    Bae, Jungu; Kuroda, Kouichi

    2014-01-01

    Proximity effect is a form of synergistic effect exhibited when cellulases work within a short distance from each other, and this effect can be a key factor in enhancing saccharification efficiency. In this study, we evaluated the proximity effect between 3 cellulose-degrading enzymes displayed on the Saccharomyces cerevisiae cell surface, that is, endoglucanase, cellobiohydrolase, and ?-glucosidase. We constructed 2 kinds of arming yeasts through genome integration: ALL-yeast, which simultaneously displayed the 3 cellulases (thus, the different cellulases were near each other), and MIX-yeast, a mixture of 3 kinds of single-cellulase-displaying yeasts (the cellulases were far apart). The cellulases were tagged with a fluorescence protein or polypeptide to visualize and quantify their display. To evaluate the proximity effect, we compared the activities of ALL-yeast and MIX-yeast with respect to degrading phosphoric acid-swollen cellulose after adjusting for the cellulase amounts. ALL-yeast exhibited 1.25-fold or 2.22-fold higher activity than MIX-yeast did at a yeast concentration equal to the yeast cell number in 1 ml of yeast suspension with an optical density (OD) at 600 nm of 10 (OD10) or OD0.1. At OD0.1, the distance between the 3 cellulases was greater than that at OD10 in MIX-yeast, but the distance remained the same in ALL-yeast; thus, the difference between the cellulose-degrading activities of ALL-yeast and MIX-yeast increased (to 2.22-fold) at OD0.1, which strongly supports the proximity effect between the displayed cellulases. A proximity effect was also observed for crystalline cellulose (Avicel). We expect the proximity effect to further increase when enzyme display efficiency is enhanced, which would further increase cellulose-degrading activity. This arming yeast technology can also be applied to examine proximity effects in other diverse fields. PMID:25304511

  7. Observation of proximities between spin-1/2 and quadrupolar nuclei: which heteronuclear dipolar recoupling method is preferable?

    PubMed

    Lu, X; Lafon, O; Trébosc, J; Tricot, G; Delevoye, L; Méar, F; Montagne, L; Amoureux, J P

    2012-10-14

    We have recently shown that the dipolar-mediated heteronuclear multiple-quantum coherence (D-HMQC) method allows observing through-space proximities between spin-1/2 ((1)H, (13)C, (31)P...) and quadrupolar ((23)Na, (27)Al...) nuclei. However, the D-HMQC effectiveness depends on the choice of the heteronuclear dipolar recoupling sequence. Here, we compare the efficiency and the robustness of four rotor-synchronized sequences: the symmetry-based ones, R4(1)(2)R4(1)(-2) and its super-cycled version, SR4(1)(2), and two schemes based on simultaneous amplitude and frequency modulations, denoted SFAM-1 and SFAM-2. For the SFAM methods, we point out efficient recoupling conditions that facilitate their experimental optimization and we introduce analytical expressions for the buildup of D-HMQC signal in the case of an isolated spin pair. We show that the main differences between these four sequences lie in the number of adjustable parameters and in their robustness with respect to chemical shift and homonuclear dipolar interactions. The relative performances of these four recoupling sequences are analyzed using average Hamiltonian theory, numerical simulations, and (27)Al-{(31)P} D-HMQC experiments on crystalline aluminophosphate. PMID:23061841

  8. Observation of proximities between spin-1/2 and quadrupolar nuclei: Which heteronuclear dipolar recoupling method is preferable?

    SciTech Connect

    Lu, X.; Lafon, O.; Trebosc, J.; Tricot, G.; Delevoye, L.; Mear, F.; Montagne, L.; Amoureux, J. P. [UCCS (CNRS-8181), Lille North of France University, Villeneuve d'Ascq 59652 (France)

    2012-10-14

    We have recently shown that the dipolar-mediated heteronuclear multiple-quantum coherence (D-HMQC) method allows observing through-space proximities between spin-1/2 ({sup 1}H, {sup 13}C, {sup 31}P Horizontal-Ellipsis ) and quadrupolar ({sup 23}Na, {sup 27}Al Horizontal-Ellipsis ) nuclei. However, the D-HMQC effectiveness depends on the choice of the heteronuclear dipolar recoupling sequence. Here, we compare the efficiency and the robustness of four rotor-synchronized sequences: the symmetry-based ones, R4{sub 1}{sup 2}R4{sub 1}{sup -2} and its super-cycled version, SR4{sub 1}{sup 2}, and two schemes based on simultaneous amplitude and frequency modulations, denoted SFAM-1 and SFAM-2. For the SFAM methods, we point out efficient recoupling conditions that facilitate their experimental optimization and we introduce analytical expressions for the buildup of D-HMQC signal in the case of an isolated spin pair. We show that the main differences between these four sequences lie in the number of adjustable parameters and in their robustness with respect to chemical shift and homonuclear dipolar interactions. The relative performances of these four recoupling sequences are analyzed using average Hamiltonian theory, numerical simulations, and {sup 27}Al-{l_brace}{sup 31}P{r_brace} D-HMQC experiments on crystalline aluminophosphate.

  9. Identification of a novel repressive element in the proximal lck promoter.

    PubMed

    Muise-Helmericks, R C; Rosen, N

    1995-11-17

    The T-cell-specific protooncogene lck, a src-related tyrosine kinase, is under the control of two promoters that give rise to transcripts differing only in their 5'-untranslated regions. The distal promoter is transcriptionally active in both peripheral and thymic T-cells, whereas expression of the proximal promoter is highest in developing thymocytes. The proximal promoter has also been shown to be selectively activated in a number of colon carcinoma cell lines. Approximately 570 base pairs of proximal promoter sequence is required for expression in both T-cells and colon carcinoma cell lines. Protein binding studies were initiated with an oligonucleotide homologous to a region that, when deleted, causes an increase in promoter activity in transgenic animals. Two proteins with approximate molecular masses of 35 and 75 kDa were found to bind to this region as determined by UV cross-linking studies. Absence of specific protein binding is correlated with a high level of proximal promoter expression. Competitive gel retardation analysis identified a 9-base pair binding site within the proximal lck promoter that is necessary for repression of transcription in cells that contain specific binding activity. Mutants of this binding site do not repress transcription. Repression does not occur in a cell line that expresses lck and lacks this activity. These data support the hypothesis that activation of lck transcription in colon carcinoma is due, at least in part, to the loss of a transcriptional repressor. PMID:7499213

  10. Renal proximal tubule angiotensin AT1A receptors regulate blood pressure

    PubMed Central

    Li, Huiping; Weatherford, Eric T.; Davis, Deborah R.; Keen, Henry L.; Grobe, Justin L.; Daugherty, Alan; Cassis, Lisa A.; Allen, Andrew M.

    2011-01-01

    All components of the renin angiotensin system necessary for ANG II generation and action have been reported to be present in renal proximal convoluted tubules. Given the close relationship between renal sodium handling and blood pressure regulation, we hypothesized that modulating the action of ANG II specifically in the renal proximal tubules would alter the chronic level of blood pressure. To test this, we used a proximal tubule-specific, androgen-dependent, promoter construct (KAP2) to generate mice with either overexpression of a constitutively active angiotensin type 1A receptor transgene or depletion of endogenous angiotensin type 1A receptors. Androgen administration to female transgenic mice caused a robust induction of the transgene in the kidney and increased baseline blood pressure. In the receptor-depleted mice, androgen administration to females resulted in a Cre recombinase-mediated deletion of angiotensin type 1A receptors in the proximal tubule and reduced blood pressure. In contrast to the changes observed at baseline, there was no difference in the blood pressure response to a pressor dose of ANG II in either experimental model. These data, from two separate mouse models, provide evidence that ANG II signaling via the type 1A receptor in the renal proximal tubule is a regulator of systemic blood pressure under baseline conditions. PMID:21753145

  11. Impact of Geographical Proximity on Health Care Seeking Behaviour in Northern Oman

    PubMed Central

    Al-Mandhari, Ahmed; Al-Adawi, Samir; Al-Zakwani, Ibrahim; Al-Shafaee, Mohammed; Eloul, Liyam

    2008-01-01

    Objectives: Despite its impact on health policy, the relationship between geographical proximity and health care seeking has received scant attention in the medical literature. This paper aims to evaluate the relationship between geographic proximity and health care usage behaviour among patients seeking medical consultation in the northern region of Oman. Methods: During 2006–2007, data was collected via face-to-face interviews among 428 randomized patients seeking medical consultation in various primary health care centres in the northern region of Oman. The association between geographical proximity as a reason to seek health care and other predictors was also analysed using multivariable logistic regression. Results: The data suggest that preference for geographical proximity as a reason for seeking health care is strongly associated with marital status, previous exposure to traditional medicine and health education, as well as history of immunisation. Conclusion: This finding supports the view from elsewhere that geographical proximity remains a strong catalyst for care seeking in Oman. The psychosocial factors affecting care seeking are discussed. PMID:21748077

  12. Professional and geographical network effects on healthcare information exchange growth: does proximity really matter?

    PubMed Central

    Yaraghi, Niam; Du, Anna Ye; Sharman, Raj; Gopal, Ram D; Ramesh, R; Singh, Ranjit; Singh, Gurdev

    2014-01-01

    Background and objective We postulate that professional proximity due to common patients and geographical proximity among practice locations are significant factors influencing the adoption of health information exchange (HIE) services by healthcare providers. The objective of this study is to investigate the direct and indirect network effects of these drivers on HIE diffusion. Design Multi-dimensional scaling and clustering are first used to create different clusters of physicians based on their professional and geographical proximities. Extending the Bass diffusion model to capture direct and indirect network effects among groups, the growth of HIE among these clusters is modeled and studied. The network effects among the clusters are investigated using adoption data over a 3-year period for an HIE based in Western New York. Measurement HIE adoption parameters—external sources of influence as well as direct and indirect network coefficients—are estimated by the extended version of the Bass diffusion model. Results Direct network effects caused by common patients among physicians are much more influential on HIE adoption as compared with previously investigated social contagion and external factors. Professional proximity due to common patients does influence adoption decisions; geographical proximity is also influential, but its effect is more on rural than urban physicians. Conclusions Flow of patients among different groups of physicians is a powerful factor in HIE adoption. Rather than merely following the market trend, physicians appear to be influenced by other physicians with whom they interact with and have common patients. PMID:24287171

  13. Proximity effect in Nb/Al, AlOxide, Al/Nb Josephson tunnel junctions

    NASA Astrophysics Data System (ADS)

    Houwman, E. P.; Gijsbertsen, J. G.; Flokstra, J.; Rogalla, H.; Le Grand, J. B.; de Korte, P. A. J.; Golubov, A. A.

    1993-03-01

    Regions with reduced energy gap induced by the proximity effect give rise to quasi-particle loss in Josephson-junction X-ray detectors, but may also be used advantageously for quasi-particle collection. The influence of the thickness of the Al proximity layers in Nb/Al1,AlO(x),Al2/Nb Josephson tunnel junctions on the electrical characteristics has been investigated theoretically and experimentally. Theoretically it is found that the strength of the proximity effect is mainly determined by the proximity parameters gammaM1 (gammaM2) of the electrodes. Good fits of the measured I-V curves with theory were obtained for junctions with thicknesses dA11 ranging from 4 to 25 nm and dA12 = 3 nm, with gammaM2 about 0.12 and gammaM1/gammaM2 = dA11/dA12. For all junctions the proximity knee remains more pronounced than predicted.

  14. Second-generation proximally coated titanium femoral component: minimum 7-year results.

    PubMed

    Lachiewicz, Paul F; Soileau, Elizabeth S; Bryant, Paul

    2007-12-01

    It is unclear whether resurfacing or fully porous-coated or proximally coated stems are the best femoral components for young patients. First-generation proximally coated titanium fiber-metal femoral components had a high rate of failure. We prospectively followed 56 patients (70 hips) whom we believed were at high risk for loosening of a cemented femoral component; all patients were implanted with one second-generation proximally coated titanium femoral component. Ten patients (11 hips) died and three patients (four hips) were lost to minimum followup. Three models of titanium fiber-metal acetabular component were implanted with screws. Patients were clinically evaluated using the Harris hip score. We used standardized radiographs to assess fixation status and osteolysis. Forty-four patients (55 hips) with a mean age of 45 years were followed for a minimum of 7 years (mean, 10.5 years; range, 7-15 years). No femoral component had been revised for any reason. Bone ingrowth (spot welding) was seen in 41 hips (75%) and proximal femoral osteolysis in only four hips. Reoperations for polyethylene wear were performed in seven patients (12.7%) and two patients had liner exchange for recurrent dislocation. Even with an articulating surface with considerable polyethylene wear debris, these second-generation proximally coated titanium fiber-metal femoral components had a survival rate of 100% at a mean 10.5-year followup. PMID:17621229

  15. Evaluation of the proximal flow field to circular and noncircular orifices of different aspect ratios.

    PubMed

    Myers, J G; Fox, J F; Elmahdi, A M; Perry, G J; Anayiotos, A S

    1997-08-01

    Investigations of valvular regurgitation attempt to specify flow field characteristics and apply them to the proximal isovelocity surface area (PISA) method for quantifying regurgitant flow. Most investigators assume a hemispherical shape to these equivelocity shells proximal to an axisymmetric (circular) orifice. However, in vivo flow fields are viscous and regurgitant openings vary in shape and size. By using centerline profiles and isovelocity surfaces, this investigation describes the flow field proximal to circular and elliptical orifices. Steady, proximal flow fields are obtained with two- and three-dimensional computational fluid dynamic (CFD) simulations. These simulations are verified by in vitro, laser-Doppler velocimetry (LDV) experiments. The data show that a unique, normalized proximal flow field results for each orifice shape independent of orifice flow or size. The distinct differences in flow field characteristics with orifice shape may provide a mechanism for evaluating orifice characteristics and regurgitant flows. Instead of the hemispherical approximation technique, this study attempts to show the potential to define a universal flow evaluation method based on the details of the flowfield according to orifice shape. Preliminary results indicate that Magnetic Resonance (MR) and Color Doppler (CD) may reproduce these flow details and allow such a procedure in vivo. PMID:9285349

  16. Expression of rat renal Na/H antiporter mRNA levels in response to respiratory and metabolic acidosis.

    PubMed Central

    Krapf, R; Pearce, D; Lynch, C; Xi, X P; Reudelhuber, T L; Pouysségur, J; Rector, F C

    1991-01-01

    The mammalian proximal tubule is an important mediator of the renal adaptive response to systemic acidosis. In chronic metabolic and respiratory acidosis the bicarbonate reabsorptive (or proton secretory) capacity is increased. This increase is mediated, at least in part, by an increase in Vmax of the luminal Na/H antiporter. To determine whether this adaptation involves increased mRNA expression, Na/H antiporter mRNA levels were measured by Northern analysis in renal cortex of rats with metabolic (6 mmol/kg body wt NH4Cl for 2 or 5 d) and respiratory (10% CO2/air balanced for 2 or 5 d) acidosis and of normal, pair-fed rats. Na/H antiporter mRNA levels were unchanged after 2 d of both metabolic and respiratory acidosis. After 5 d, however, Na/H antiporter mRNA expression was increased 1.76 +/- 0.12-fold in response to metabolic acidosis (P less than 0.005, n = 8), but was not different from normal in response to respiratory acidosis: 1.1 +/- 0.2 (NS, n = 8). Thus, the renal adaptive response to metabolic acidosis involves increased cortical Na/H antiporter mRNA levels. In contrast, the enhanced proximal tubule Na/H antiporter activity and bicarbonate reabsorption in respiratory acidosis seem to involve mechanisms other than increased Na/H antiporter gene expression. Images PMID:1846882

  17. Multiple remote-US preexposures and the blocking effect produced by a proximal-US.

    PubMed

    Misanin, J R; Hoefel, T D; Riedy, C A; Wilson, H A; Hinderliter, C F

    Weanling, young-adult, and old-age Wistar albino rats were used to determine whether number of unconditioned stimulus (US) presentations, given 24 h or more (remote preexposure) prior to conditioning, alters the blocking effect of a single-US preexposure given 2 h before (proximal) taste aversion conditioning. As the number of remote-US preexposures increased from 0 to 6, the ability of the proximal-US preexposure to block conditioning initially increased then decreased for all age groups. Of the models put forth to explain US preexposure effects on conditioned taste aversion (CTA), only Wagner's information processing model adequately explained the reduction of the blocking effect of the proximal-US preexposure produced as a result of increasing remote-US preexposures. PMID:11134702

  18. Ipsilateral distal femoral and proximal tibial epiphyseal growth plate injury: a case report

    PubMed Central

    2013-01-01

    Introduction Both the isolated distal femoral epiphysiolysis and the isolated proximal tibial epiphysiolysis are the least common epiphyseal injuries. Even though they are uncommon, they have a high incidence rate of complications. Case presentation We present a case with Gustilo-Anderson grade 3b open and Salter-Harris type 1 epiphysiolysis of the distal femur and proximal tibia caused by a farm machinery accident. The patient was a 10-year-old boy, treated by open reduction and internal fixation. Conclusion Although distal femoral and proximal tibial growth plate injuries are rarely seen benign fractures, their management requires meticulous care. Anatomic reduction is important, especially to minimize the risk of growth arrest and the development of degenerative arthritis. However, there is a high incidence of growth arrest and neurovascular injury with these type of fractures. PMID:23724954

  19. Transcriptional adaptation to Clcn5 knockout in proximal tubules of mouse kidney.

    PubMed

    Wright, Jerry; Morales, Marcelo M; Sousa-Menzes, Jackson; Ornellas, Debora; Sipes, Jennifer; Cui, Yan; Cui, Isabelle; Hulamm, Phuson; Cebotaru, Valeriu; Cebotaru, Liudmila; Guggino, William B; Guggino, Sandra E

    2008-05-13

    Dent disease has multiple defects attributed to proximal tubule malfunction including low-molecular-weight proteinuria, aminoaciduria, phosphaturia, and glycosuria. To understand the changes in kidney function of the Clc5 chloride/proton exchanger gene knockout mouse model of Dent disease, we examined gene expression profiles from proximal S1 and S2 tubules of mouse kidneys. We found many changes in gene expression not known previously to be altered in this disease. Genes involved in lipid metabolism, organ development, and organismal physiological processes had the greatest number of significantly changed transcripts. In addition, genes of catalytic activity and transporter activity also had a great number of changed transcripts. Overall, 720 genes are expressed differentially in the proximal tubules of the Dent Clcn5 knockout mouse model compared with those of control wild-type mice. The fingerprint of these gene changes may help us to understand the phenotype of Dent disease. PMID:18349385

  20. Spontaneous Accumulation of Globotriaosylceramide (Gb3) in Proximal Renal Tubules in an ICR Mouse

    PubMed Central

    Mutsuga, Mayu; Asaoka, Yoshiji; Togashi, Yuko; Imura, Naoko; Miyoshi, Tomoya; Miyamoto, Yohei

    2013-01-01

    This report describes spontaneous cytoplasmic vacuolation in the proximal renal tubules of a 7-week-old male ICR [Crlj:CD1(ICR)] mouse. The contents of vacuoles were positively stained with periodic acid-Schiff (PAS) and Sudan black, and the membranes were positive on immunohistochemical staining for lysosomal-associated membrane protein-2 (LAMP-2), a marker of lysosomal membrane. Electron microscopy revealed electron-dense lamellar bodies in the proximal tubular epithelial cells. These histopathological features are similar to those in ?-galactosidase A-deficient mice, in which globotriaosylceramide (Gb3), a glycosphingolipid, accumulates in lysosomes. When we performed immunohistochemical staining for Gb3, the contents of vacuoles were positively stained. From these results, spontaneous cytoplasmic vacuolation in the proximal renal tubules in the mouse was identified as lysosomal accumulation of Gb3. PMID:24526817

  1. Orbiter/payload proximity operations SES Postsim report. Lateral approach and other techniques

    NASA Technical Reports Server (NTRS)

    Olszewski, O.

    1978-01-01

    Various approach and stationkeeping simulations (proximity operations) were conducted in the Shuttle engineering simulator (SES). This simulator is the first to dynamically include the Orbiter reaction control system (RCS) plume effects on a payload being recovered after rendezvous operations. A procedure for braking, using the simultaneous firing of both jets, was evaluated and found very useful for proximity operations. However this procedure is very inefficient in the RCS usage and requires modifications to the digital autopilot (DAP) software. A new final approach, the lateral approach technique (LAT), or the momentum vector proximity approach, was also evaluated in the simulations. The LAT, which included a tailfirst approach for braking, was evaluated successfully with both inertial and gravity stabilized payloads.

  2. Fibulin-1 suppresses endothelial to mesenchymal transition in the proximal outflow tract.

    PubMed

    Harikrishnan, Keerthi; Cooley, Marion A; Sugi, Yukiko; Barth, Jeremy L; Rasmussen, Lars M; Kern, Christine B; Argraves, Kelley M; Argraves, W Scott

    2015-05-01

    Endothelial to mesenchymal transition (EMT) that occurs during cardiac outflow tract (OFT) development is critical for formation of the semilunar valves. Fibulin-1 (Fbln1) is an extracellular matrix protein that is present at several sites of EMT, including the OFT (i.e., E9.5-10.5). The aim of this study was to determine the role of Fbln1 in EMT during the earliest events of OFT development. Examination of proximal OFT cushions in Fbln1 null embryos detected hypercellularity at both E9.5 (93% increase; p?=?0.002) and E10.5 (43% increase; p?=?0.01) as compared to wild type, suggesting that Fbln1 normally suppresses OFT endocardial cushion EMT. This was supported by studies of proximal OFT cushion explants, which showed that explants from Fbln1 null embryos displayed a 58% increase in cells migrating from the explants as compared to wild type (p?=?0.005). We next evaluated the effects of Fbln1 deficiency on the expression of factors that regulate proximal OFT EMT. At E9.5, Fbln1 null proximal OFT endocardium and EMT-derived mesenchyme showed increased TGF?2 (58% increase; p?=?0.01) and increased Snail1-positive nuclei (27% increase; p?=?0.0003). Histological examination of OFT cushions in Fbln1 null embryos (E9.5) also detected cells present in the cushion that were determined to be erythrocytes based on round morphology, autofluorescence, and positive staining for hemoglobin. Erythrocytes were also detected in Fbln1 null OFT cushions at E10.5. Together, the findings indicate that Fbln1 normally suppresses proximal OFT EMT preventing proximal cushion hypercellularity and blood cell accumulation. PMID:25575930

  3. Stenting for proximal para-anastomotic stenosis of an infrarenal aortic bypass graft.

    PubMed

    Ramaiah, Venkatesh; Thompson, Charles; Harvey, Adrian; Rodriguez, Julio A; Diethrich, Edward B

    2002-01-01

    We present a case in which endovascular stenting was used for recurrent proximal para-anastomotic stenosis 11 years after aorto-bi-iliac bypass grafting for severe aorto-iliac occlusive disease. A 55-year-old woman presented with worsening bilateral hip and buttock claudication. At presentation, her resting ankle-brachial indices were 0.87 bilaterally and decreased to 0.39 on the right and 0.40 on the left with exercise. Aortography demonstrated a proximal para-anastomotic aortic graft stenosis without distal outflow obstruction, patent superficial femoral arteries, and good triple-vessel runoff bilaterally The stenosis was dilated with a 9- x 4-cm OPTA balloon angioplasty catheter. A Palmaz stent (P424, Cordis) was mounted on a 10- x 4-cm OPTA balloon catheter and deployed across the proximal stenosis. Completion arteriography confirmed adequate placement and reduction in the degree of stenosis. There was no pressure gradient across the proximal anastomosis. At our patient's 1-week follow-up visit, her resting ankle-brachial indices were both greater than 1.0 and her exercise ankle-brachial indices were 1.0 bilaterally She remained asymptomatic at 13 months. Most late sequelae of aortic graft surgery involve the distal anastomosis and are resolved surgically without complicated techniques. However, revision at the proximal anastomosis involves the aorta directly and therefore requires open abdominal dissection and aortic cross-clamping. Percutaneous aortic stenting for primary aortoiliac disease has been shown to reduce operative time, cost, and hospital stays, to improve patency and to be durable. Our clinical experience with aortic stenting for primary disease led us to consider this procedure for recurrent proximal stenosis. PMID:11995850

  4. NA57 main results

    E-print Network

    G. E. Bruno; for the NA57 Collaboration

    2007-10-15

    The CERN NA57 experiment was designed to study the production of strange and multi-strange particles in heavy ion collisions at SPS energies; its physics programme is essentially completed. A review of the main results is presented.

  5. Highly sensitive proximity and tactile sensor based on composite with dielectric elastomer and carbon microcoils

    NASA Astrophysics Data System (ADS)

    Nguyen, Tien D.; Park, Junwoo; Lee, Choonghan; Nguyen, Canh T.; Lee, Dong-hyuk; Kim, Uikyum; Phung, Hoa; Nam, Jae-do; Koo, Ja Choon; Moon, Hyungpil; Choi, Hyouk R.

    2014-03-01

    This work presents a dual purpose sensor for collecting proximity and tactile information by using a composite with dielectric elastomer (DE) and Carbon Micro Coils (CMC). CMC is a coil-like carbon microstructure with the size of several hundred micrometers, and its electrical characteristics change with the distance between the object or via physical contact. Especially, the impedance change of the composite depending on the distance can be used as the principle for proximity sensing. We present a method to process the materials by using dielectric materials and additives. A prototype of the sensor is fabricated and its feasibility is experimentally validated.

  6. Design and fabrication of stretchable proximity-tactile sensor using carbon micro coils

    NASA Astrophysics Data System (ADS)

    Park, Junwoo; Nguyen, Tien Dat; Kim, Uikyum; Lee, Dong-Hyuk; Nguyen, Canh Toan; Phung, Hoa; Nam, Jaedo; Moon, Hyungpil; Koo, Ja Choon; Choi, Hyouk Ryeol

    2015-04-01

    This paper presents a stretchable proximity-tactile sensor (PTS) using Carbon Micro Coils (CMC). The PTS consists of pairs of multiple active electrodes and a common ground electrode on the same plane. Thus, the sensor is tolerable to the repetitive contacts from external forces. The top layer consists of dielectric elastomer substrate mixed with 5% of CMC, so that it can respond to the proximity and tactile stimuli. Electrodes are located under the top layer and optimally organized to reduce the number of wirings. The sensor is fabricated by molding and casting methods. As the result, a 4 × 4 sensor prototype is made and its performance are experimentally evaluated.

  7. Real-time proximity cues for teleoperation using model-based force reflection

    NASA Astrophysics Data System (ADS)

    Bruno, Guy; Morgenthaler, Matthew K.

    1992-03-01

    The problem of providing model-based proximity cues using force reflection for teleoperation under time delay is addressed. A novel use of artificial potential fields is proposed as a teleoperator aid to efficiently provide a predictive tactile display. Several new artificial potential models are presented which are used to convey accurate shape and proximity information by generating handcontroller forces based on the potential gradient. These new potential gradients are shown to have an efficient implementation via exact computation as a neural network. A real-time prototype implementation and integration with Martin Marietta's teleautonomous testbed is discussed. Evaluations are made with human operators performing tasks using industrial manipulators under time delay scenarios.

  8. Proximal trisomy 1q in a girl with developmental delay and minor anomalies

    SciTech Connect

    Furforo, L. [Hospital Materno Infantil Ramon Sarda, Buenos Aires (Argentina)] [Hospital Materno Infantil Ramon Sarda, Buenos Aires (Argentina); [Instituto Nacional de Genetica Medica, Buenos Aires (Argentina); Rittler, M. [Hospital Materno Infantil Ramon Sarda, Buenos Aires (Argentina)] [Hospital Materno Infantil Ramon Sarda, Buenos Aires (Argentina); Slavutsky, I.R. [Academia Nacional de Medicina, Buenos Aires (Argentina)] [Academia Nacional de Medicina, Buenos Aires (Argentina)

    1996-09-06

    We report on a girl with developmental delay, macrocephaly, facial asymmetry, small downturned palpebral fissures, high and narrow palate, micrognathia, short neck, a heart defect, and unilateral renal agenesis. Cytogenetic analysis showed a proximal tandem duplication of the long arm of chromosome one (1q12{r_arrow}q21.3). This abnormality was suggested by G-and C-banding but it was specifically characterized by fluorescent in situ hybridization (FISH). Clinical findings in our patient are compared with those of the literature in an attempt to delineate the phenotype in patients with proximal 1q duplication. 12 refs., 4 figs., 1 tab.

  9. Fully automated algorithm for the segmentation of the middle and proximal phalanges of digitized hand radiographs

    NASA Astrophysics Data System (ADS)

    Duryea, Jeffrey W.; Jiang, Yebin; Countryman, Peter; Genant, Harry K.

    1998-06-01

    Rheumatoid arthritis of the hand can be characterized and assessed by the narrowing of the phalangeal joint spaces. These are ordinarily scored semi-quantitatively by a radiologist using radiographs of the hand. Software which delineates and measures the joint spaces would be a useful tool for diagnosis. The first part of such an algorithm has been developed which segments and identifies eight individual bones on digitized hand radiographs: the middle and proximal phalanges of the 2nd to 5th digits. The software also determines the locations of the distal interphalangeal, proximal interphalangeal, and metacarpophalangeal joint spaces for each digit.

  10. ANALYSIS OF METHODS FOR DETECTING THE PROXIMITY EFFECT IN QUASAR SPECTRA

    SciTech Connect

    Dall'Aglio, Aldo [Astrophysikalisches Institut Potsdam, An der Sternwarte 16, D-14482 Potsdam (Germany); Gnedin, Nickolay Y., E-mail: adaglio@aip.d [Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States)

    2010-10-10

    Using numerical simulations of structure formation, we investigate several methods for determining the strength of the proximity effect in the H I Ly{alpha} forest. We analyze three high-resolution ({approx}10 kpc) redshift snapshots (z-bar=4,3, and 2.25) of a Hydro-Particle-Mesh simulation to obtain realistic absorption spectra of the H I Ly{alpha} forest. We model the proximity effect along the simulated sight lines with a simple analytical prescription based on the assumed quasar luminosity and the intensity of the cosmic UV background (UVB). We begin our analysis investigating the intrinsic biases thought to arise in the widely adopted standard technique of combining multiple lines of sight when searching for the proximity effect. We confirm the existence of these biases, albeit smaller than previously predicted with simple Monte Carlo simulations. We then concentrate on the analysis of the proximity effect along individual lines of sight. After determining its strength with a fiducial value of the UVB intensity, we construct the proximity effect strength distribution (PESD). We confirm that the PESD inferred from the simple averaging technique accurately recovers the input strength of the proximity effect at all redshifts. Moreover, the PESD closely follows the behaviors found in observed samples of quasar spectra. However, the PESD obtained from our new simulated sight lines presents some differences to that of simple Monte Carlo simulations. At all redshifts, we find a smaller dispersion of the strength parameters, the source of the corresponding smaller biases found when combining multiple lines of sight. After developing three new theoretical methods for recovering the strength of the proximity effect on individual lines of sight, we compare their accuracy to the PESD from the simple averaging technique. All our new approaches are based on the maximization of the likelihood function, albeit invoking some modifications. The new techniques presented here, in spite of their complexity, fail to recover the input proximity effect in an unbiased way, presumably due to some (unknown) higher order correlations in the spectrum. Thus, employing complex three-dimensional simulations, we provide strong evidence in favor of the PESD obtained from the simple averaging technique, as a method of estimating the UVB intensity, free of any intrinsic biases.

  11. Proximity effect induced magnetoresistance hysteresis loops in a topological insulator/YIG heterostructure

    NASA Astrophysics Data System (ADS)

    Montazeri, Mohammad; Lang, Murong; Onbasli, Mehmet C.; Kou, Xufeng; He, Liang; Ross, Caroline A.; Wang, Kang L.

    2014-03-01

    We experimentally demonstrate the proximity effect induced hysteretic magnetoresistance in an 8 quintuple layers of Bi2Se3 films grown on Gallium Gadolinium Garnet (GGG) (111) substrates with a 50 nm Yttrium Iron Garnet (YIG) buffer layer by molecular beam epitaxy. With in-plane and out-of-plane magnetic field, square wave shaped and butterfly shaped resistance hysteresis loops can be observed up to 25 K, respectively. The relationship between the hysteretic MR curves and the magnetic switching of the YIG will be discussed in the context of a proximity effect between the YIG and the TI.

  12. Graphene in proximity to magnetic insulating LaMnO{sub 3}

    SciTech Connect

    Cheng, Guanghui; Wei, Laiming, E-mail: laiming@ustc.edu.cn, E-mail: cgzeng@ustc.edu.cn; Cheng, Long; Liang, Haixing; Zhang, Xiaoqiang; Li, Hui [Hefei National Laboratory for Physical Sciences at the Microscale (HFNL) and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Yu, Guolin [Shanghai Institute of Technical Physics, Chinese Academy of Science, Shanghai 200083 (China); Zeng, Changgan, E-mail: laiming@ustc.edu.cn, E-mail: cgzeng@ustc.edu.cn [Hefei National Laboratory for Physical Sciences at the Microscale (HFNL) and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); International Center for Quantum Design of Functional Materials (ICQD), HFNL, University of Science and Technology of China, Hefei, Anhui 230026 (China); Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-09-29

    Proximity to functional substrates may enhance the coupling between the quantum degrees of freedom and thus develop nontrivial quantum effects in graphene. Here, we demonstrate the successful fabrication of graphene in proximity to atomically flat magnetic insulating LaMnO{sub 3} films. The insulating nature of the LaMnO{sub 3} films not only ensures the electronic transport only occur in the graphene layers but also allow them to serve as dielectric layers for gating. Transport measurements reveal anomalous behaviors, including asymmetrical longitudinal magnetoresistivity and nonlinear Hall effect. This work may pave a way toward the realization of intriguing quantum phases in graphene.

  13. Cystine uptake by cultured cells originating from dog proximal tubule segments

    Microsoft Academic Search

    Beatrice States; Robert Reynolds; Judithann Lee; Stanton Segal

    1990-01-01

    Summary  Large numbers of kidney epithelial cells were cultured successfully from isolated dog proximal tubule segments. Cells in primary\\u000a culture and in first passage retained the cystine-dibasic amino acid co-transporter system which is found in vivo and in freshly\\u000a isolated proximal tubule segments. In contrast to other cultured cells, the cystine-glutamate anti-porter was absent in primary\\u000a cultures. However, this anti-porter system

  14. Regional Distribution Models with Lack of Proximate Predictors: Africanized Honeybees Expanding North

    NASA Technical Reports Server (NTRS)

    Jarnevich, Catherine S.; Esaias, Wayne E.; Ma, Peter L. A.; Morisette, Jeffery T.; Nickeson, Jaime E.; Stohlgren, Thomas J.; Holcombe, Tracy R.; Nightingale, Joanne M.; Wolfe, Robert E.; Tan, Bin

    2014-01-01

    Species distribution models have often been hampered by poor local species data, reliance on coarse-scale climate predictors and the assumption that species-environment relationships, even with non-proximate predictors, are consistent across geographical space. Yet locally accurate maps of invasive species, such as the Africanized honeybee (AHB) in North America, are needed to support conservation efforts. Current AHB range maps are relatively coarse and are inconsistent with observed data. Our aim was to improve distribution maps using more proximate predictors (phenology) and using regional models rather than one across the entire range of interest to explore potential differences in drivers.

  15. Light chain deposition disease and proximal tubulopathy in two successive kidney allografts.

    PubMed

    Drieux, Fanny; Loron, Marie-Charlotte; Francois, Arnaud; Bertrand, Dominique; Etienne, Isabelle; Bender, Sebastien; Godin, Michel; Guerrot, Dominique

    2015-06-01

    Light chain proximal tubulopathy (LCPT) is a rare kidney disease associated with plasma cell dyscrasias, characterized by light chain deposits in the proximal tubular cells, with or without crystal formation. We describe an exceptional case of LCPT without crystal formation in a kidney allograft, in a patient who underwent two renal transplants for a light chain deposition disease (LCDD) complicating smoldering myeloma. This is the first description of this association in successive kidney allografts. We concisely describe pathology of LCDD and LCPT and discuss potential pathophysiological mechanisms relating these two conditions. PMID:25492671

  16. Phytochemical investigation and proximate analysis on the leaves of Cnidoscolus aconitifolius.

    PubMed

    Oyagbemi, Ademola A; Odetola, Adebimpe A; Azeez, Odunayo I

    2011-03-01

    The study was designed to carry out the phytochemical screening and the proximate analysis of Cnidoscolus aconitifolius leaves. The results obtained showed the presence of tannins, saponin, alkaloids, and flavonoids with the absence of glycosides. The proximate analysis and mineral composition of C. aconitifolius leaves showed high levels of crude protein, ash, and fiber, in that order, and low fat content with concomitant presence of minerals such as sodium, manganese, magnesium, potassium, calcium, iron, phosphate, and zinc. The leaves of C. aconitifolius have high nutrient potentials and could be used as nutraceuticals in complementary foods, especially in sub-Saharan Africa. PMID:21182430

  17. Factors associated with the lumbar spine and proximal femur bone mineral density in older men

    Microsoft Academic Search

    Jane A. Cauley; Robin L. Fullman; Katie L. Stone; Joseph M. Zmuda; Douglas C. Bauer; Elizabeth Barrett-Connor; Kristine Ensrud; Edith M. C. Lau; Eric S. Orwoll

    2005-01-01

    Bone mass is a major determinant of fracture, but there have been few comprehensive studies of the correlates of bone mineral density (BMD) in older men. The objective of the current cross-sectional analysis was to determine the factors associated with BMD of the lumbar spine and proximal femur in a large population-based sample of older men enrolled in The Osteoporotic

  18. Large Area Tactile Sensor based on Proximity Connection of Tactile Sensing Elements

    E-print Network

    Shinoda, Hiroyuki

    Large Area Tactile Sensor based on Proximity Connection of Tactile Sensing Elements Hiromasa of tactile sensor chips in a large area robot skin. RPC is an electrode whose length is a quarter- nector and TDC sheet, which allows sensor chips to connect with TDC sheet stably. Simulation results

  19. Social service availability & proximity and the over-representation of minority children in child welfare.

    PubMed

    Dorch, Edwina L; Bathman, Jake; Foster, David; Ingels, Laura; Lee, Chongmyoung; Miramontes, Claudia; Youngblood, Jo

    2010-01-01

    The goal of this study was to assess whether child welfare services were available and proximal in identified, predominantly Black and Hispanic zip code areas of three southern cities. GIS mapping of services contained in a state 2-1-1 community services data base revealed that there were no treatment services and/or no public transportation and/or lengthy public (bus) transportation times in 50% of the identified areas of one city and in almost 25% of the three cities combined. The authors suggest service availability and proximity should increase the likelihood of parent enrollment, attendance and completion which should increase parent dependency court compliance rates. Further, they suggest that court compliance rates should increase the rate of return of Black children to their parents and thereby reduce child welfare caseloads. Given, the logic of their argument, the authors go on to recommend that child welfare administrators annually perform GIS analyses of State 2-1-1 community services data bases to keep abreast of child welfare service availability and proximity. Additionally, they offer a number of recommendations for how to increase service availability and proximity in predominantly Black and Hispanic urban areas. PMID:21329189

  20. Secure Proximity Detection for NFC Devices based on Ambient Sensor Data

    E-print Network

    Saxena, Nitesh

    Secure Proximity Detection for NFC Devices based on Ambient Sensor Data Tzipora Halevi1 , Di Ma3. In particular, in the context of an NFC transaction, the bank server can validate the transaction if both the NFC phone and reader are precisely at the same location thereby preventing a form of a devastating