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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. 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

  3. Synergistic alpha-1 and alpha-2 adrenergic stimulation of rat proximal nephron Na+/H+ exchange

    SciTech Connect

    Gesek, F.A.; Cragoe, E.J. Jr.; Strandhoy, J.W.

    1989-06-01

    Both alpha-1 and alpha-2 adrenoceptors have been localized to the renal cortex, with the majority of binding sites on the proximal tubule. Because the major regulator of Na+ uptake into the proximal tubule is the Na+/H+ exchanger, and because alpha-1 and alpha-2 adrenoceptors stimulate it in other tissues, we tested the hypothesis that both alpha adrenoceptor subtypes can increase Na+ uptake into the proximal nephron by stimulating the Na+/H+ antiporter. Enhancement of Na+ transport by agonists was studied in isolated rat proximal tubules by determining the uptake of 22Na that was suppressible by the Na+/H+ inhibitor, 5-(N-ethyl-N-isopropyl)amiloride (EIPA). The phorbol ester, phorbol-12-myristate-13-acetate, (0.1 microM), directly stimulated the antiporter through protein kinase C and increased EIPA-suppressible 22Na uptake 250% above control. The alpha-1 adrenoceptor agonists, cirazoline and phenylephrine, in addition to the mixed agonist, norepinephrine, maximally stimulated uptake by 226 to 232% at 1 microM concentrations. alpha-2 agonists produced a range of maximal stimulations at 1 microM from 65% with guanabenz to 251% with B-HT 933. Increases in 22Na uptake by agonists were inhibited by selective adrenergic antagonists and by EIPA. The drugs did not change the EIPA-resistant component of 22Na uptake. Inasmuch as the adrenoceptor subtypes likely stimulated Na+/H+ exchange by differing intracellular pathways impinging upon common transport steps, we examined whether simultaneous stimulation of both pathways was additive. Submaximal concentrations (5 nM each) of alpha-1 and alpha-2 adrenoceptor agonists in combination synergistically enhanced 22Na uptake to a level similar to 1 microM concentrations of adrenoceptor agonists alone or in combination.

  4. 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.

  5. 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. )

    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.

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

    PubMed

    Bidet, M; Tauc, M; Merot, J; Vandewalle, A; Poujeol, P

    1987-11-01

    The purpose of this study was to investigate the characteristics of the Na+-H+ 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 (pHi) was measured in a bicarbonate-free medium [extracellular pH (pHe) = 7.30], using the fluorescent dye 2,7-biscarboxyethyl-5(6)-carboxyfluorescein (BCECF). Resting pHi was 7.13 +/- 0.04 (n = 11) at 20-22 degrees C. Cells were acid loaded with nigericin in choline solution and H+ efflux, induced by extracellular Na+ (Nae), was calculated using a buffering power of 23.6 +/- 0.6 mmol.1-1.pH unit-1 (n = 19) estimated by NH4Cl exposure. In isolated proximal cells, the Na+-H+ antiporter had an apparent Km for Nae of 86.7 +/- 1.5 mM (n = 4) and was competitively inhibited by amiloride with a Ki of 33.3 +/- 6.4 X 10(-6) M (n = 3). Lowering pHe, inhibited the Na+-H+ exchanger. This inhibition was not purely competitive and the Ki was 40.4 +/- 12.7 nM (n = 3). The Na+-H+ exchange was greatly activated when the cytoplasm was acidified. The intracellular H+ concentration dependence did not follow simple Michaelis-Menten kinetics. Of the different cations tested on pHi recovery, such as Li+, choline+, K+, and tetramethylammonium, only Li+ induced an alkalinization of acidified cells similar to that of Na+. 22Na influx measurements indicated that cellular depletion of Na+ stimulated Na+-H+ exchange. The results permit the conclusion that the isolation procedures did not impair the main features of the Na+-H+ 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. PMID:2825539

  7. Na+-H+ exchanger-1 (NHE1) regulation in kidney proximal tubule.

    PubMed

    Parker, Mark D; Myers, Evan J; Schelling, Jeffrey R

    2015-06-01

    The ubiquitously expressed plasma membrane Na(+)-H(+) exchanger NHE1 is a 12 transmembrane-spanning protein that directs important cell functions such as homeostatic intracellular volume and pH control. The 315 amino acid cytosolic tail of NHE1 binds plasma membrane phospholipids and multiple proteins that regulate additional, ion-translocation independent functions. This review focuses on NHE1 structure/function relationships, as well as the role of NHE1 in kidney proximal tubule functions, including pH regulation, vectorial Na(+) transport, cell volume control and cell survival. The implications of these functions are particularly critical in the setting of progressive, albuminuric kidney diseases, where the accumulation of reabsorbed fatty acids leads to disruption of NHE1-membrane phospholipid interactions and tubular atrophy, which is a poor prognostic factor for progression to end stage renal disease. This review amplifies the vital role of the proximal tubule NHE1 Na(+)-H(+) exchanger as a kidney cell survival factor.

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

    PubMed

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

    2010-05-01

    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 PGE(2), 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 α-subunit encoded by the ATP1A1 gene, as well as a β-subunit encoded by the ATP1B1 gene. Transient transfection studies conducted with pHβ1-1141 Luc, a human ATP1B1 promoter/luciferase construct, indicate that both PGE(1) and PGE(2) are stimulatory. The evidence for the involvement of both the cAMP and Ca(2+) 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 PGE(1) 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 PGE(1) 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 PGE(1) on Na-K-ATPase was observed and was associated with an increase in the level of Na-K-ATPase in the basolateral membrane.

  9. NaCl reflection coefficients in proximal tubule apical and basolateral membrane vesicles. Measurement by induced osmosis and solvent drag.

    PubMed

    Pearce, D; Verkman, A S

    1989-06-01

    Two independent methods, induced osmosis and solvent drag, were used to determine the reflection coefficients for NaCl (sigma NaCl) in brush border and basolateral membrane vesicles isolated from rabbit proximal tubule. In the induced osmosis method, vesicles loaded with sucrose were subjected to varying inward NaCl gradients in a stopped-flow apparatus. sigma NaCl was determined from the osmolality of the NaCl solution required to cause no initial osmotic water flux as measured by light scattering (null point). By this method sigma NaCl was greater than 0.92 for both apical and basolateral membranes with best estimates of 1.0. sigma NaCl was determined by the solvent drag method using the Cl-sensitive fluorescent indicator, 6-methoxy-N-[3-sulfopropyl]quinolinium (SPQ), to detect the drag of Cl into vesicles by inward osmotic water movement caused by an outward osmotic gradient. sigma NaCl was determined by comparing experimental data with theoretical curves generated using the coupled flux equations of Kedem and Katchalsky. By this method we found that sigma NaCl was greater than 0.96 for apical and greater than 0.98 for basolateral membrane vesicles, with best estimates of 1.0 for both membranes. These results demonstrate that sigma NaCl for proximal tubule apical and basolateral membranes are near unity. Taken together with previous results, these data suggest that proximal tubule water channels are long narrow pores that exclude NaCl. PMID:2765660

  10. Differential regulation of Na+ transporters along nephron during ANG II-dependent hypertension: distal stimulation counteracted by proximal inhibition.

    PubMed

    Nguyen, Mien T X; Lee, Donna H; Delpire, Eric; McDonough, Alicia A

    2013-08-15

    During angiotensin II (ANG II)-dependent hypertension, ANG II stimulates, while hypertension inhibits, Na(+) transporter activity to balance Na(+) output to input. This study tests the hypothesis that ANG II infusion activates Na(+) transporters in the distal nephron while inhibiting transporters along the proximal nephron. Male Sprague-Dawley rats were infused with ANG II (400 ng·kg(-1)·min(-1)) or vehicle for 2 wk. Kidneys were dissected (cortex vs. medulla) or fixed for immunohistochemistry (IHC). ANG II increased mean arterial pressure by 40 mmHg, urine Na(+) by 1.67-fold, and urine volume by 3-fold, evidence for hypertension and pressure natriuresis. Na(+) transporters' abundance and activation [assessed by phosphorylation (-P) or proteolytic cleavage] were measured by immunoblot. During ANG II infusion Na(+)/H(+) exchanger 3 (NHE3) abundance decreased in both cortex and medulla; Na-K-2Cl cotransporter 2 (NKCC2) decreased in medullary thick ascending loop of Henle (TALH) and increased, along with NKCC2-P, in cortical TALH; Na-Cl cotransporter (NCC) and NCC-P increased in the distal convoluted tubule; and epithelial Na(+) channel subunits and their cleaved forms were increased in both cortex and medulla. Like NKCC2, STE20/SPS1-related proline alanine-rich kinase (SPAK) and SPAK-P were decreased in medulla and increased in cortex. By IHC, during ANG II NHE3 remained localized to proximal tubule microvilli at lower abundance, and the differential regulation of NKCC2 and NKCC2-P in cortex versus medulla was evident. In summary, ANG II infusion increases Na(+) transporter abundance and activation from cortical TALH to medullary collecting duct while the hypertension drives a natriuresis response evident as decreased Na(+) transporter abundance and activation from proximal tubule through medullary TALH. PMID:23720346

  11. NaCl reflection coefficients in proximal tubule apical and basolateral membrane vesicles. Measurement by induced osmosis and solvent drag.

    PubMed

    Pearce, D; Verkman, A S

    1989-06-01

    Two independent methods, induced osmosis and solvent drag, were used to determine the reflection coefficients for NaCl (sigma NaCl) in brush border and basolateral membrane vesicles isolated from rabbit proximal tubule. In the induced osmosis method, vesicles loaded with sucrose were subjected to varying inward NaCl gradients in a stopped-flow apparatus. sigma NaCl was determined from the osmolality of the NaCl solution required to cause no initial osmotic water flux as measured by light scattering (null point). By this method sigma NaCl was greater than 0.92 for both apical and basolateral membranes with best estimates of 1.0. sigma NaCl was determined by the solvent drag method using the Cl-sensitive fluorescent indicator, 6-methoxy-N-[3-sulfopropyl]quinolinium (SPQ), to detect the drag of Cl into vesicles by inward osmotic water movement caused by an outward osmotic gradient. sigma NaCl was determined by comparing experimental data with theoretical curves generated using the coupled flux equations of Kedem and Katchalsky. By this method we found that sigma NaCl was greater than 0.96 for apical and greater than 0.98 for basolateral membrane vesicles, with best estimates of 1.0 for both membranes. These results demonstrate that sigma NaCl for proximal tubule apical and basolateral membranes are near unity. Taken together with previous results, these data suggest that proximal tubule water channels are long narrow pores that exclude NaCl.

  12. Solvent drag measurement of transcellular and basolateral membrane NaCl reflection coefficient in kidney proximal tubule.

    PubMed

    Shi, L B; Fushimi, K; Verkman, A S

    1991-08-01

    The NaCl reflection coefficient in proximal tubule has important implications for the mechanisms of near isosmotic volume reabsorption. A new fluorescence method was developed and applied to measure the transepithelial (sigma NaClTE) and basolateral membrane (sigma NaClcl) NaCl reflection coefficients in the isolated proximal straight tubule from rabbit kidney. For sigma NaClTE measurement, tubules were perfused with buffers containing 0 Cl, the Cl-sensitive fluorescent indicator 6-methoxy-N-[3-sulfopropyl] quinolinium and a Cl-insensitive indicator fluorescein sulfonate, and bathed in buffers of differing cryoscopic osmolalities containing NaCl. The transepithelial Cl gradient along the length of the tubule was measured in the steady state by a quantitative ratio imaging technique. A mathematical model based on the Kedem-Katchalsky equations was developed to calculate the axial profile of [Cl] from tubule geometry, lumen flow, water (Pf) and NaCl (PNaCl) permeabilities, and sigma NaClTE. A fit of experimental results to the model gave PNaCl = (2.25 +/- 0.2) x 10(-5) cm/s and sigma NaClTE = 0.98 +/- 0.03 at 23 degrees C. For measurement of sigma NaClbl, tubule cells were loaded with SPQ in the absence of Cl. NaCl solvent drag was measured from the time course of NaCl influx in response to rapid (less than 1 s) Cl addition to the bath solution. With bath-to-cell cryoscopic osmotic gradients of 0, -60, and +30 mosmol, initial Cl influx was 1.23, 1.10, and 1.25 mM/s; a fit to a mathematical model gave sigma NaClbl = 0.97 +/- 0.04. These results indicate absence of NaCl solvent drag in rabbit proximal tubule. The implications of these findings for water and NaCl movement in proximal tubule are evaluated.

  13. Azilsartan Improves Salt Sensitivity by Modulating the Proximal Tubular Na+-H+ Exchanger-3 in Mice.

    PubMed

    Hatanaka, Masaki; Kaimori, Jun-Ya; Yamamoto, Satoko; Matsui, Isao; Hamano, Takayuki; Takabatake, Yoshitsugu; Ecelbarger, Carolyn M; Takahara, Shiro; Isaka, Yoshitaka; Rakugi, Hiromi

    2016-01-01

    A potent angiotensin II type-1 receptor blocker, azilsartan, has been reported to reduce blood pressure more effectively than candesartan. Interestingly, azilsartan can also restore the circadian rhythm of blood pressure. We hypothesized that azilsartan could also improve salt sensitivity; thus, we examined the effect of azilsartan on sodium handling in renal tubules. Subtotal nephrectomized C57BL/6 mice received azilsartan (1.0 mg/kg/day), candesartan (0.3 mg/kg/day), or vehicle via the oral route in conjunction with a normal- (0.3%) or high-salt (8.0%) diet. Two weeks later, the azilsartan group showed significantly lower blood pressure during the light period than the candesartan and vehicle groups (azilsartan: 103.1 ± 1.0; candesartan: 111.7 ± 2.7; vehicle: 125.5 ± 2.5 mmHg; P < 0.05; azilsartan or candesartan vs. vehicle). The azilsartan group also showed higher urinary fractional excretion of sodium during the dark period than the candesartan and vehicle groups (azilsartan: 21.37 ± 3.69%; candesartan: 14.17 ± 1.42%; vehicle: 13.85 ± 5.30%; P < 0.05 azilsartan vs. candesartan or vehicle). A pressure-natriuresis curve demonstrated that azilsartan treatment restored salt sensitivity. Immunofluorescence and western blotting showed lower levels of Na+-H+ exchanger-3 (NHE3) protein (the major sodium transporter in renal proximal tubules) in the azilsartan group, but not in the candesartan or vehicle groups. However, azilsartan did not affect NHE3 transcription levels. Interestingly, we did not observe increased expression of downstream sodium transporters, which would have compensated for the increased flow of sodium and water due to non-absorption by NHE3. We also confirmed the mechanism stated above using cultured opossum kidney proximal tubular cells. Results revealed that a proteasomal inhibitor (but not a lysosomal inhibitor) blocked the azilsartan-induced decrease in NHE3 protein expression, suggesting that azilsartan increases NHE3 ubiquitination. In

  14. Azilsartan Improves Salt Sensitivity by Modulating the Proximal Tubular Na+-H+ Exchanger-3 in Mice

    PubMed Central

    Hatanaka, Masaki; Kaimori, Jun-Ya; Yamamoto, Satoko; Matsui, Isao; Hamano, Takayuki; Takabatake, Yoshitsugu; Ecelbarger, Carolyn M.; Takahara, Shiro; Isaka, Yoshitaka; Rakugi, Hiromi

    2016-01-01

    A potent angiotensin II type-1 receptor blocker, azilsartan, has been reported to reduce blood pressure more effectively than candesartan. Interestingly, azilsartan can also restore the circadian rhythm of blood pressure. We hypothesized that azilsartan could also improve salt sensitivity; thus, we examined the effect of azilsartan on sodium handling in renal tubules. Subtotal nephrectomized C57BL/6 mice received azilsartan (1.0 mg/kg/day), candesartan (0.3 mg/kg/day), or vehicle via the oral route in conjunction with a normal- (0.3%) or high-salt (8.0%) diet. Two weeks later, the azilsartan group showed significantly lower blood pressure during the light period than the candesartan and vehicle groups (azilsartan: 103.1 ± 1.0; candesartan: 111.7 ± 2.7; vehicle: 125.5 ± 2.5 mmHg; P < 0.05; azilsartan or candesartan vs. vehicle). The azilsartan group also showed higher urinary fractional excretion of sodium during the dark period than the candesartan and vehicle groups (azilsartan: 21.37 ± 3.69%; candesartan: 14.17 ± 1.42%; vehicle: 13.85 ± 5.30%; P < 0.05 azilsartan vs. candesartan or vehicle). A pressure—natriuresis curve demonstrated that azilsartan treatment restored salt sensitivity. Immunofluorescence and western blotting showed lower levels of Na+-H+ exchanger-3 (NHE3) protein (the major sodium transporter in renal proximal tubules) in the azilsartan group, but not in the candesartan or vehicle groups. However, azilsartan did not affect NHE3 transcription levels. Interestingly, we did not observe increased expression of downstream sodium transporters, which would have compensated for the increased flow of sodium and water due to non-absorption by NHE3. We also confirmed the mechanism stated above using cultured opossum kidney proximal tubular cells. Results revealed that a proteasomal inhibitor (but not a lysosomal inhibitor) blocked the azilsartan-induced decrease in NHE3 protein expression, suggesting that azilsartan increases NHE3 ubiquitination. In

  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. Lack of effect of peritubular protein on passive NaCl transport in the rabbit proximal tubule.

    PubMed Central

    Berry, C A

    1983-01-01

    The effect of peritubular protein removal on passive NaCl transport was examined in the isolated rabbit proximal convoluted tubule (PCT). Three modes of passive NaCl transport were tested: (a) paracellular backflux of NaCl, (b) convective flow of NaCl through junctional complexes, and (c) anion gradient-dependent NaCl transport. The effect of peritubular protein removal on the paracellular permeability to NaCl was examined using transepithelial specific resistance. Eight PCT were perfused with ultrafiltrate (UF) and bathed in either serum or UF. Transepithelial specific resistance averaged 14.5 +/- 1.9 in the presence and 13.7 +/- 1.7 omega cm2 in the absence of peritubular protein. The effect of peritubular protein removal on the convective flow of a NaCl solution across functional complexes was examined in the absence of active transport by using colloid osmotic pressure (COP) gradients. 12 PCT were perfused with simple salt solutions in Donnan equilibrium with and without protein at 20 degrees C. A COP gradient of 60.1 and -60.1 mmHg drove only 0.06 and -0.23 nl/min, respectively. These values are approximately 10% of the value predicted for an effect of peritubular protein on NaCl solution flow (1.98 nl/min) and are approximately equal to the value predicted for pure water equilibration for the small osmotic pressure difference between solutions in Donnan equilibrium (0.17-0.18 nl/min). The effect of peritubular protein removal on the passive absorption of NaCl driven by anion concentration gradients was examined in seven PCT perfused with a high chloride solution simulating late proximal tubular fluid and bathed in either serum or UF at 20 degrees C. Volume absorption averaged 0.34 +/- 0.20 in the presence and 0.39 +/- 0.20 nl/mm min in the absence of peritubular protein. In conclusion, peritubular protein removal did not significantly affect any of the three distinct modes of passive NaCl transport tested. The lack of effect of peritubular protein removal on

  17. Stimulation of Na/sup +//H/sup +/ antiport is an early event in hypertrophy of renal proximal tubular cells

    SciTech Connect

    Fine, L.G.; Badie-Dezfooly, B.; Lowe, A.G.; Hamzeh, A.; Wells, J.; Salehmoghaddam, S.

    1985-03-01

    Renal hypertrophy in vivo is achieved by an increase in protein content per cell and an increase in cell size with minimal hyperplasia. Hypertrophied renal tubular cells remain quiescent and demonstrate an increase in transcellular transport rates. This situation was simulated in vitro by exposing a confluent, quiescent primary culture of rabbit renal proximal tubular cells to either insulin, prostaglandin E/sub 1/, or hypertonic NaCl for 24 or 48 hr. Protein per cell increased by 20-30% with little or no increase in (/sup 3/H)thymidine incorporation into DNA. Mean cell volume was also increased in insulin- and hypertonic NaCl-treated but not in prostaglandin E/sub 1/-treated cells. Two hours of exposure to the growth stimuli increased amiloride-sensitive Na/sup +/ uptake, Na-dependent H/sup +/ efflux, and ouabain-sensitive Rb/sup +/ uptake, indicating that stimulation of Na/sup +//H/sup +/ antiport (exchange) occurs as an early event in their action. Hypertrophied cells continued to demonstrate enhanced Na/sup +//H/sup +/ antiport after the growth stimuli were removed for 3 hr, by which time their acute effects are reversed.

  18. Evidence for neutral transcellular NaCl transport and neutral basolateral chloride exit in the rabbit proximal convoluted tubule.

    PubMed Central

    Baum, M; Berry, C A

    1984-01-01

    The electrical nature of active NaCl transport and the significance of a basolateral membrane chloride conductance were examined in isolated perfused rabbit proximal convoluted tubules (PCT). PCT were perfused with a high chloride solution that simulated late proximal tubular fluid and were bathed in an albumin solution that simulated rabbit serum in the control and recovery periods. The electrical nature of NaCl transport was examined by bathing the tubules in a high chloride albumin solution where there were no anion gradients. Volume reabsorption (Jv) during the control and recovery period was 0.56 and 0.51 nl/mm X min, respectively, and 0.45 nl/mm X min when the tubules were bathed in a high chloride bath. The transepithelial potential difference (PD) during the control and recovery periods averaged 2.3 mV, but decreased to 0.0 mV in the absence of anion gradients, which indicated that NaCl transport is electroneutral. Further evidence that NaCl transport is electroneutral was obtained by examining the effect of addition of 0.01 mM ouabain in PCT perfused and bathed with high chloride solutions. The Jv was 0.54 nl/mm X min in the control period and not statistically different from zero after inhibition of active transport. The PD was not different from zero in both periods. Two groups of studies examined the role of basolateral membrane Cl- conductance in NaCl transport. First, depolarizing the basolateral membrane with 2 mM bath Ba++ did not significantly affect Jv or PD. Second, the effect of the presumptive Cl- conductance inhibitor anthracene-9-CO2H was examined. Anthracene-9-CO2H did not significantly affect Jv or PD. In conclusion, these data show that NaCl transport in the PCT is electroneutral and transcellular and provide evidence against a significant role for basolateral membrane chloride conductance in the rabbit PCT. PMID:6736248

  19. Phosphorylation of rat kidney Na-K pump at Ser938 is required for rapid angiotensin II-dependent stimulation of activity and trafficking in proximal tubule cells.

    PubMed

    Massey, Katherine J; Li, Quanwen; Rossi, Noreen F; Keezer, Susan M; Mattingly, Raymond R; Yingst, Douglas R

    2016-02-01

    How angiotensin (ANG) II acutely stimulates the Na-K pump in proximal tubules is only partially understood, limiting insight into how ANG II increases blood pressure. First, we tested whether ANG II increases the number of pumps in plasma membranes of native rat proximal tubules under conditions of rapid activation. We found that exposure to 100 pM ANG II for 2 min, which was previously shown to increase affinity of the Na-K pump for Na and stimulate activity threefold, increased the amount of the Na-K pump in plasma membranes of native tubules by 33%. Second, we tested whether previously observed increases in phosphorylation of the Na-K pump at Ser(938) were part of the stimulatory mechanism. These experiments were carried out in opossum kidney cells, cultured proximal tubules stably coexpressing the ANG type 1 (AT1) receptor, and either wild-type or a S938A mutant of rat kidney Na-K pump under conditions found by others to stimulate activity. We found that 10 min of incubation in 10 pM ANG II stimulated activity of wild-type pumps from 2.3 to 3.5 nmol K · mg protein(-1) · min(-1) and increased the amount of the pump in the plasma membrane by 80% but had no effect on cells expressing the S938A mutant. We conclude that acute stimulation of Na-K pump activity in native rat proximal tubules includes increased trafficking to the plasma membrane and that phosphorylation at Ser(938) is part of the mechanism by which ANG II directly stimulates activity and trafficking of the rat kidney Na-K pump in opossum kidney cells. PMID:26582472

  20. Phosphorylation of rat kidney Na-K pump at Ser938 is required for rapid angiotensin II-dependent stimulation of activity and trafficking in proximal tubule cells.

    PubMed

    Massey, Katherine J; Li, Quanwen; Rossi, Noreen F; Keezer, Susan M; Mattingly, Raymond R; Yingst, Douglas R

    2016-02-01

    How angiotensin (ANG) II acutely stimulates the Na-K pump in proximal tubules is only partially understood, limiting insight into how ANG II increases blood pressure. First, we tested whether ANG II increases the number of pumps in plasma membranes of native rat proximal tubules under conditions of rapid activation. We found that exposure to 100 pM ANG II for 2 min, which was previously shown to increase affinity of the Na-K pump for Na and stimulate activity threefold, increased the amount of the Na-K pump in plasma membranes of native tubules by 33%. Second, we tested whether previously observed increases in phosphorylation of the Na-K pump at Ser(938) were part of the stimulatory mechanism. These experiments were carried out in opossum kidney cells, cultured proximal tubules stably coexpressing the ANG type 1 (AT1) receptor, and either wild-type or a S938A mutant of rat kidney Na-K pump under conditions found by others to stimulate activity. We found that 10 min of incubation in 10 pM ANG II stimulated activity of wild-type pumps from 2.3 to 3.5 nmol K · mg protein(-1) · min(-1) and increased the amount of the pump in the plasma membrane by 80% but had no effect on cells expressing the S938A mutant. We conclude that acute stimulation of Na-K pump activity in native rat proximal tubules includes increased trafficking to the plasma membrane and that phosphorylation at Ser(938) is part of the mechanism by which ANG II directly stimulates activity and trafficking of the rat kidney Na-K pump in opossum kidney cells.

  1. Estrogen directly and specifically downregulates NaPi-IIa through the activation of both estrogen receptor isoforms (ERα and ERβ) in rat kidney proximal tubule

    PubMed Central

    Burris, Dara; Webster, Rose; Sheriff, Sulaiman; Faroqui, Rashma; Levi, Moshe; Hawse, John R.

    2015-01-01

    We have previously demonstrated that estrogen (E2) downregulates phosphate transporter NaPi-IIa and causes phosphaturia and hypophosphatemia in ovariectomized rats. In the present study, we examined whether E2 directly targets NaPi-IIa in the proximal tubule (PT) and studied the respective roles of estrogen receptor isoforms (ERα and ERβ) in the downregulation of NaPi-IIa using both in vivo and an in vitro expression systems. We found that estrogen specifically downregulates NaPi-IIa but not NaPi-IIc or Pit2 in the kidney cortex. Proximal tubules incubated in a “shake” suspension with E2 for 24 h exhibited a dose-dependent decrease in NaPi-IIa protein abundance. Results from OVX rats treated with specific agonists for either ERα [4,4′,4″;-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol, PPT] or ERβ [4,4′,4″-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol, DPN] or both (PPT + DPN), indicated that only the latter caused a sharp downregulation of NaPi-IIa, along with significant phosphaturia and hypophosphatemia. Lastly, heterologous expression studies demonstrated that estrogen downregulated NaPi-IIa only in U20S cells expressing both ERα and ERβ, but not in cells expressing either receptor alone. In conclusion, these studies demonstrate that rat PT cells express both ERα and ERβ and that E2 induces phosphaturia by directly and specifically targeting NaPi-IIa in the PT cells. This effect is mediated via a mechanism involving coactivation of both ERα and ERβ, which likely form a functional heterodimer complex in the rat kidney proximal tubule. PMID:25608964

  2. Renal proximal tubule Na,K-ATPase is controlled by CREB-regulated transcriptional coactivators as well as salt-inducible kinase 1.

    PubMed

    Taub, Mary; Garimella, Sudha; Kim, Dongwook; Rajkhowa, Trivikram; Cutuli, Facundo

    2015-12-01

    Sodium reabsorption by the kidney is regulated by locally produced natriuretic and anti-natriuretic factors, including dopamine and norepinephrine, respectively. Previous studies indicated that signaling events initiated by these natriuretic and anti-natriuretic factors achieve their effects by altering the phosphorylation of Na,K-ATPase in the renal proximal tubule, and that protein kinase A (PKA) and calcium-mediated signaling pathways are involved. The same signaling pathways also control the transcription of the Na,K-ATPase β subunit gene atp1b1 in renal proximal tubule cells. In this report, evidence is presented that (1) both the recently discovered cAMP-regulated transcriptional coactivators (CRTCs) and salt-inducible kinase 1 (SIK1) contribute to the transcriptional regulation of atp1b1 in renal proximal tubule (RPT) cells and (2) renal effectors, including norepinephrine, dopamine, prostaglandins, and sodium, play a role. Exogenously expressed CRTCs stimulate atp1b1 transcription. Evidence for a role of endogenous CRTCs includes the loss of transcriptional regulation of atp1b1 by a dominant-negative CRTC, as well as by a CREB mutant, with an altered CRTC binding site. In a number of experimental systems, SIK phosphorylates CRTCs, which are then sequestered in the cytoplasm, preventing their nuclear effects. Consistent with such a role of SIK in primary RPT cells, atp1b1 transcription increased in the presence of a dominant-negative SIK1, and in addition, regulation by dopamine, norepinephrine, and monensin was disrupted by a dominant-negative SIK1. These latter observations can be explained if SIK1 is phosphorylated and inactivated in the presence of these renal effectors. Our results support the hypothesis that Na,K-ATPase in the renal proximal tubule is regulated at the transcriptional level via SIK1 and CRTCs by renal effectors, in addition to the previously reported control of the phosphorylation of Na,K-ATPase.

  3. Ouabain stimulates Na-K-ATPase through a sodium/hydrogen exchanger-1 (NHE-1)-dependent mechanism in human kidney proximal tubule cells

    PubMed Central

    Holthouser, Kristine A.; Mandal, Amritlal; Merchant, Michael L.; Schelling, Jeffrey R.; Delamere, Nicholas A.; Valdes, Ronald R.; Tyagi, Suresh C.; Lederer, Eleanor D.

    2010-01-01

    Recent investigations demonstrate increased Na/H exchanger-1 (NHE-1) activity and plasma levels of ouabain-like factor in spontaneously hypertensive rats. At nanomolar concentrations, ouabain increases Na-K-ATPase activity, induces cell proliferation, and activates complex signaling cascades. We hypothesize that the activity of NHE-1 and Na-K-ATPase are interdependent. To test whether treatment with picomolar ouabain regulates Na-K-ATPase through an NHE-1-dependent mechanism, we examined the role of NHE-1 in ouabain-mediated stimulation of Na-K-ATPase in kidney proximal tubule cell lines [opossum kidney (OK), HK-2, HKC-5, and HKC-11] and rat kidney basolateral membranes. Ouabain stimulated Na-K-ATPase activity and tyrosine phosphorylation in cells that express NHE-1 (OK, HKC-5, and HKC-11) but not in HK-2 cells that express very low levels of NHE-1. Inhibition of NHE-1 with 5 μM EIPA, a NHE-1-specific inhibitor, prevented ouabain-mediated stimulation of 86Rb uptake and Na-K-ATPase phosphorylation in OK, HKC-5, and HKC-11 cells. Expression of wild-type NHE-1 in HK2 cells restored regulation of Na-K-ATPase by picomolar ouabain. Treatment with picomolar ouabain increased membrane expression of Na-K-ATPase and enhanced NHE-1-Na-K-ATPase α1-subunit association. Treatment with ouabain (1 μg·kg body wt−1·day−1) increased Na-K-ATPase activity, expression, phosphorylation, and association with NHE-1 increased in rat kidney cortical basolateral membranes. Eight days' treatment with ouabain (1 μg·kg body wt−1·day−1) resulted in increased blood pressure in these rats. These results suggest that the association of NHE-1 with Na-K-ATPase is critical for ouabain-mediated regulation of Na-K-ATPase and that these effects may play a role in cardioglycoside-stimulated hypertension. PMID:20427472

  4. Apical Na+/H+ antiporter and glycolysis-dependent H+-ATPase regulate intracellular pH in the rabbit S3 proximal tubule.

    PubMed Central

    Kurtz, I

    1987-01-01

    The apical transport processes responsible for proton secretion were studied in the isolated perfused rabbit S3 proximal tubule. Intracellular pH (pHi) was measured with the pH dye, 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein. Steady state pHi in S3 tubules in nominally HCO3(-)-free solutions was 7.08 +/- 0.03. Removal of Na+ (lumen) caused a decrease in pHi of 0.34 +/- 0.06 pH/min. The decrease in pHi was inhibited 62% by 1 mM amiloride (lumen) and was unaffected by 50 microM 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (lumen) and Cl- removal (lumen, bath). After a brief exposure to 20 mM NH4Cl, pHi fell by approximately 0.7 and recovered at a rate of 0.89 +/- 0.15 pH/min in the nominal absence of Na+, HCO3-, organic anions, and SO4(2-) (lumen, bath). 1 mM N,N'-dicyclohexylcarbodiimide (lumen), 1 mM N-ethylmaleimide (lumen), 0.5 mM colchicine (bath), and 0.5 mM iodoacetic acid (lumen, bath) inhibited the Na+-independent pHi recovery rate by 73%, 55%, 77%, and 86%, respectively, whereas 1 mM KCN (lumen, bath) did not inhibit pHi recovery. Reduction of intracellular, but not extracellular chloride, also decreased the Na+-independent pHi recovery rate. In conclusion, the S3 proximal tubule has an apical Na+/H+ antiporter with a Michaelis constant for Na+ of 29 mM and a maximum velocity of 0.47 pH/min. S3 tubules also possess a plasma membrane H+-ATPase that can regulate pHi, has a requirement for intracellular chloride, and utilizes ATP derived primarily from glycolysis. PMID:2888787

  5. Proximity of Na+ -Ca2+ -exchanger and sarco/endoplasmic reticulum Ca2+ pump in pig coronary artery smooth muscle: fluorescence microscopy.

    PubMed

    Kuszczak, Iwona; Kuner, Rajneet; Samson, Sue E; Grover, Ashok K

    2010-06-01

    Pig coronary artery smooth muscle expresses the Na(+)-Ca(2+)-exchanger NCX1 and the sarco/endoplasmic reticulum (SER) Ca(2+) pump SERCA2. NCX has been proposed to play a role in refilling the SER Ca(2+) pool. Caveolae may also direct Ca(2+) traffic during cell signaling. Here, we use immunofluorescence microscopy to determine if there is proximity between NCX1, SERCA2, and the caveolar protein caveolin-1. Stacks of images of cell surface domains were analyzed. Image stacks for one protein were analyzed for overlap with another protein, with and without randomization or image shifting. Within the resolution of light microscopy, there is significant overlap in the distributions of NCX1, SERCA2, and caveolin-1 but the three proteins are not always co-localized. The proximity between NCX1, SERCA2 is consistent with the assertion that NCX may supply Ca(2+) for refilling the SER but this relationship is only partial. Similarly, caveolae may direct traffic in some Ca(2+) signaling pathways but not others.

  6. 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

  7. 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

  8. Proximal effect of the nitrogen ligands in the catalytic epoxidation of olefins by the NaOCl/manganese(III) porphyrin system

    SciTech Connect

    Meunier, B.; de Carvalho, M.; Bortolini, O.; Momenteau, M.

    1988-01-13

    Using synthetic manganese porphyrin complexes with an imidazole or a pyridine ligand covalently attached to the macrocycle, the control of the reaction rate, product selectivity, and stereoselectivity by the axial ligand trans to the active site of the catalyst is reported. The results clearly illustrate the proximal effect on nitrogen ligands in this cytochrome P-450 model. 33 refs., 1 fig., 2 tabs.

  9. Role of H{sub 2}O{sub 2} on the kinetics of low-affinity high-capacity Na{sup +}-dependent alanine transport in SHR proximal tubular epithelial cells

    SciTech Connect

    Pinto, Vanda; Pinho, Maria Joao; Jose, Pedro A.; Soares-da-Silva, Patricio

    2010-07-30

    Research highlights: {yields} H{sub 2}O{sub 2} in excess is required for the presence of a low-affinity high-capacity component for the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake in SHR PTE cells only. {yields} It is suggested that Na{sup +} binding in renal ASCT2 may be regulated by ROS in SHR PTE cells. -- Abstract: The presence of high and low sodium affinity states for the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake in immortalized renal proximal tubular epithelial (PTE) cells was previously reported (Am. J. Physiol. 293 (2007) R538-R547). This study evaluated the role of H{sub 2}O{sub 2} on the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake of ASCT2 in immortalized renal PTE cells from Wistar Kyoto rat (WKY) and spontaneously hypertensive rat (SHR). Na{sup +} dependence of [{sup 14}C]-L-alanine uptake was investigated replacing NaCl with an equimolar concentration of choline chloride in vehicle- and apocynin-treated cells. Na{sup +} removal from the uptake solution abolished transport activity in both WKY and SHR PTE cells. Decreases in H{sub 2}O{sub 2} levels in the extracellular medium significantly reduced Na{sup +}-K{sub m} and V{sub max} values of the low-affinity high-capacity component in SHR PTE cells, with no effect on the high-affinity low-capacity state of the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake. After removal of apocynin from the culture medium, H{sub 2}O{sub 2} levels returned to basal values within 1 to 3 h in both WKY and SHR PTE cells and these were found stable for the next 24 h. Under these experimental conditions, the Na{sup +}-K{sub m} and V{sub max} of the high-affinity low-capacity state were unaffected and the low-affinity high-capacity component remained significantly decreased 1 day but not 4 days after apocynin removal. In conclusion, H{sub 2}O{sub 2} in excess is required for the presence of a low-affinity high-capacity component for the Na{sup +}-dependent [{sup 14}C]-L-alanine uptake in SHR PTE cells only

  10. [Effect of artificial NaC1 and KC1 gradients on the active transport of organic acids in energy-depleted kidney proximal tubules. II. The KC1 gradient].

    PubMed

    Mozhaeva, M G; Bresler, V M; Nikiforov, A A

    1982-07-01

    The stimulatory effect of KCL in bath medium on fluorescein uptake in superficial proximal tubules in the absence of Na in bath medium was observed on Na- and energy-depleted slices of the rat kidney outer cortex. In the absence of K gradient between bath medium and tubular cells, the fluorescein uptake increased with raising the intracellular K concentration. The efflux of fluorescein from the tubules was inversely proportional to K concentration in the cells. Visual control showed that at high K concentrations fluorescein was accumulated mainly in the tubular walls (i. e. in the cytoplasm of tubular cells). It is suggested that the raise of K concentration in cells results in the intracellular binding of organic acid.

  11. Proximity fuze

    DOEpatents

    Harrison, Thomas R.

    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.

  12. Proximity fuze

    DOEpatents

    Harrison, T.R.

    1987-07-10

    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 circuit. 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 from the target. Additional circuitry distinguishes pulses reflected from the target from background solar radiation. 3 figs.

  13. Proteinases inhibit H(+)-ATPase and Na+/H+ exchange but not water transport in apical and endosomal membranes from rat proximal tubule.

    PubMed

    Sabolić, I; Shi, L B; Brown, D; Ausiello, D A; Verkman, A S

    1992-01-10

    A marked increase in water permeability can be induced in Xenopus oocytes by injection of mRNA from tissues that express water channels, suggesting that the water channel is a protein. In view of this and previous reports which showed that proteinases may interfere with mercurial inhibition of water transport in red blood cells (RBC), we examined the influence of trypsin, chymotrypsin, papain, pronase, subtilisin and thermolysin on water permeability as well as on ATPase activity, H(+)-pump, passive H+ conductance, and Na+/H+ exchange in apical brush-border vesicles (BBMV) and endosomal (EV) vesicles from rat renal cortex. H+ transport was measured by Acridine orange fluorescence quenching and water transport by stopped-flow light scattering. As measured by potential-driven H+ accumulation in BBMV and EV, proteinase treatment had little effect on vesicle integrity. In BBMV, ecto-ATPase activity was inhibited by 15-30%, Na+/H+ exchange by 20-55%, and H+ conductance was unchanged. Osmotic water permeability (Pf) was 570 microns/s and was inhibited 85-90% by 0.6 mM HgCl2; proteinase treatment did not affect Pf or the HgCl2 inhibition. In EV, NEM-sensitive H+ accumulation and ATPase activity were inhibited by greater than 95%. Pf (140 microns/s) and HgCl2 inhibition (75-85%) were not influenced by proteinase treatment. SDS-PAGE showed selective digestion of multiple polypeptides by proteinases. These results confirm the presence of water channels in BBMV and EV and demonstrate selective inhibition of ATPase function and Na+/H+ exchange by proteinase digestion. The lack of effect of proteinases on water transport by mercurials. We conclude that the water channel may be a small integral membrane protein which, unlike the H(+)-ATPase and Na+/H+ exchanger, has no functionally important membrane domains that are sensitive to proteolysis. PMID:1309658

  14. Proximal Tibial Bone Graft

    MedlinePlus

    ... Complications Potential problems after a PTBG include infection, fracture of the proximal tibia and pain related to the procedure. Frequently Asked Questions If proximal tibial bone graft is taken from my knee, will this prevent me from being able to ...

  15. Neurogenic regulation of proximal bicarbonate and chloride reabsorption.

    PubMed

    Cogan, M G

    1986-01-01

    Although a change in renal nerve activity is known to alter proximal reabsorption, it is unclear whether reabsorption of NaHCO3 or NaCl or both are affected. Sprague-Dawley rats (n = 10) were studied using free-flow micropuncture techniques during euvolemia and following acute ipsilateral denervation. Glomerular filtration rate and single nephron glomerular filtration rate were stable. Absolute proximal bicarbonate reabsorption fell following denervation (933 +/- 40 to 817 +/- 30 pmol/min) with a parallel reduction in chloride reabsorption (1,643 +/- 116 to 1,341 +/- 129 peq/min). Urinary sodium, potassium, bicarbonate, and chloride excretion all increased significantly. To further assess the physiological significance of neurogenic modulation of proximal transport, other rats (n = 6) were subjected to acute unilateral nephrectomy (AUN). There is evidence that AUN induces a contralateral natriuresis (renorenal reflex) at least partially by causing inhibition of efferent renal nerve traffic. AUN caused significant changes in proximal NaHCO3 and NaCl reabsorption as well as in whole kidney electrolyte excretion in the same pattern as had denervation. Prior denervation of the remaining kidney prevented the proximal and whole kidney response to AUN (n = 6). In conclusion, depression of renal nerve activity inhibits both NaHCO3 and NaCl reabsorption in the rat superficial proximal convoluted tubule. The data are consistent with the hypothesis that changes in renal nerve activity modify whole kidney electrolyte excretion under physiological conditions at least partially by regulating proximal transport.

  16. Maturation of rat proximal tubule chloride permeability.

    PubMed

    Baum, Michel; Quigley, Raymond

    2005-12-01

    We have previously shown that neonate rabbit tubules have a lower chloride permeability but comparable mannitol permeability compared with adult proximal tubules. The surprising finding of lower chloride permeability in neonate proximals compared with adults impacts net chloride transport in this segment, which reabsorbs 60% of the filtered chloride in adults. However, this maturational difference in chloride permeability may not be applicable to other species. The present in vitro microperfusion study directly examined the chloride and mannitol permeability using in vitro perfused rat proximal tubules during postnatal maturation. Whereas there was no maturational change in mannitol permeability, chloride permeability was 6.3 +/- 1.3 x 10(-5) cm/s in neonate rat proximal convoluted tubule and 16.1 +/- 2.3 x 10(-5) cm/s in adult rat proximal convoluted tubule (P < 0.01). There was also a maturational increase in chloride permeability in the rat proximal straight tubule (5.1 +/- 0.6 x 10(-5) cm/s vs. 9.3 +/- 0.6 x 10(-5) cm/s, P < 0.01). There was no maturational change in bicarbonate-to-chloride permeabilities (P(HCO3)/P(Cl)) in the rat proximal straight tubules (PST) and proximal convoluted tubules (PCT) or in the sodium-to-chloride permeability (P(Na)/P(Cl)) in the proximal straight tubule; however, there was a significant maturational decrease in proximal convoluted tubule P(Na)/P(Cl) with postnatal development (1.31 +/- 0.12 in neonates vs. 0.75 +/- 0.06 in adults, P < 0.001). There was no difference in the transepithelial resistance measured by current injection and cable analysis in the PCT, but there was a maturational decrease in the PST (7.2 +/- 0.8 vs. 4.6 +/- 0.1 ohms x cm2, P < 0.05). These studies demonstrate there are maturational changes in the rat paracellular pathway that impact net NaCl transport during development. PMID:16051720

  17. Proximal humerus fractures.

    PubMed

    Price, Matthew C; Horn, Pamela L; Latshaw, James C

    2013-01-01

    Proximal humerus fractures are among the most common fractures associated with osteoporosis. With an aging population, incidence of these fractures will only increase. The proximal humerus not only forms the lateral portion of the shoulder articulation but also has significant associations with musculoskeletal and neurovascular structures. As a result, fractures of the proximal humerus can significantly impact not only the function of the shoulder joint, but the health and function of the entire upper extremity as well. Understanding of these fractures, the management options, and associated nursing care, can help reduce morbidity rate and improve functional outcomes.

  18. Bulk Topological Proximity Effect.

    PubMed

    Hsieh, Timothy H; Ishizuka, Hiroaki; Balents, Leon; Hughes, Taylor L

    2016-02-26

    Existing proximity effects stem from systems with a local order parameter, such as a local magnetic moment or a local superconducting pairing amplitude. Here, we demonstrate that despite lacking a local order parameter, topological phases also may give rise to a proximity effect of a distinctively inverted nature. We focus on a general construction in which a topological phase is extensively coupled to a second system, and we argue that, in many cases, the inverse topological order will be induced on the second system. To support our arguments, we rigorously establish this "bulk topological proximity effect" for all gapped free-fermion topological phases and representative integrable models of interacting topological phases. We present a terrace construction which illustrates the phenomenological consequences of this proximity effect. Finally, we discuss generalizations beyond our framework, including how intrinsic topological order may also exhibit this effect.

  19. Proximal fifth metatarsal fractures.

    PubMed

    Ramponi, Denise R

    2013-01-01

    The most common fracture of the foot is a fracture of the proximal fifth metatarsal. In general, there are 3 types of fractures involving the proximal fifth metatarsal area, including a proximal diaphyseal stress fracture, a Jones fracture, and an avulsion fracture of the tuberosity. Some fractures of the fifth metatarsal heal without difficulty, whereas some have the potential for nonunion or delayed healing. Each fracture has some variation in the anatomical location on the fifth metatarsal, the mechanism of injury, the radiographic findings, and the treatment plan. Avulsion fractures of the tuberosity often heal without difficulty, yet fractures distal to the area of insertion of the peroneus brevis tendon are prone to nonunion and delayed healing (). Differential diagnosis of a fifth metatarsal midfoot injury includes ankle sprains, midfoot sprains, plantar facial ruptures, peroneus tendon ruptures, and other foot fractures.

  20. Capacitive proximity sensor

    DOEpatents

    Kronberg, J.W.

    1994-05-31

    A proximity sensor based on a closed field circuit is disclosed. The circuit comprises a ring oscillator using a symmetrical array of plates that creates an oscillating displacement current. The displacement current varies as a function of the proximity of objects to the plate array. Preferably the plates are in the form of a group of three pair of symmetric plates having a common center, arranged in a hexagonal pattern with opposing plates linked as a pair. The sensor produces logic level pulses suitable for interfacing with a computer or process controller. The proximity sensor can be incorporated into a load cell, a differential pressure gauge, or a device for measuring the consistency of a characteristic of a material where a variation in the consistency causes the dielectric constant of the material to change. 14 figs.

  1. Capacitive proximity sensor

    DOEpatents

    Kronberg, James W.

    1994-01-01

    A proximity sensor based on a closed field circuit. The circuit comprises a ring oscillator using a symmetrical array of plates that creates an oscillating displacement current. The displacement current varies as a function of the proximity of objects to the plate array. Preferably the plates are in the form of a group of three pair of symmetric plates having a common center, arranged in a hexagonal pattern with opposing plates linked as a pair. The sensor produces logic level pulses suitable for interfacing with a computer or process controller. The proximity sensor can be incorporated into a load cell, a differential pressure gauge, or a device for measuring the consistency of a characteristic of a material where a variation in the consistency causes the dielectric constant of the material to change.

  2. Unusual proximal tibiofibular synostosis.

    PubMed

    Takai, S; Yoshino, N; Hirasawa, Y

    1999-01-01

    Proximal tibiofibular synostosis without multiple hereditary exostosis is extremely rare and only 7 cases have been reported in the literature. All of the previously reported cases accompanied deformities such as distal positioning of the proximal tibiofibular joint, leg length discrepancy, bowing of the fibula, and valgus deformity of the knee. The present case of a 24-year-old man had neither a history of trauma nor deformity around the knee. Therefore, it was suggested that this type of synostosis occurred after epiphyseal plate closure. PMID:10741527

  3. XQL and Proximal Nodes.

    ERIC Educational Resources Information Center

    Baeza-Yates, Ricardo; Navarro, Gonzalo

    2002-01-01

    Discussion of models that have been developed to structure text documents for information retrieval focuses on XML and its proposed query language XQL. Considers efficiency of the query engine and shows that an already existing model, Proximal Nodes, can be used as an efficient query engine behind an XQL front-end. (Author/LRW)

  4. Traumatic proximal tibiofibular dislocation.

    PubMed

    Burgos, J; Alvarez-Montero, R; Gonzalez-Herranz, P; Rapariz, J M

    1997-01-01

    Proximal tibiofibular dislocation is an exceptional lesion. Rarer still is its presentation in childhood. We describe the clinical case of a 6-year-old boy, the victim of a road accident. He had a tibiofibular dislocation associated with a metaphyseal fracture of the tibia.

  5. 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,…

  6. 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

  7. Proximal Point Methods Revisited

    NASA Astrophysics Data System (ADS)

    Boikanyo, Oganeditse A.; Moroşanu, Gheorghe

    2011-09-01

    The proximal point methods have been widely used in the last decades to approximate the solutions of nonlinear equations associated with monotone operators. Inspired by the iterative procedure defined by B. Martinet (1970), R.T. Rockafellar introduced in 1976 the so-called proximal point algorithm (PPA) for a general maximal monotone operator. The sequence generated by this iterative method is weakly convergent under appropriate conditions, but not necessarily strongly convergent, as proved by O. Güler (1991). This fact explains the introduction of different modified versions of the PPA which generate strongly convergent sequences under appropriate conditions, including the contraction-PPA defined by H.K. Xu in 2002. Here we discuss Xu's modified PPA as well as some of its generalizations. Special attention is paid to the computational errors, in particular the original Rockafellar summability assumption is replaced by the condition that the error sequence converges to zero strongly.

  8. Proximity Networks and Epidemics

    NASA Astrophysics Data System (ADS)

    Guclu, Hasan; Toroczkai, Zoltán

    2007-03-01

    We presented the basis of a framework to account for the dynamics of contacts in epidemic processes, through the notion of dynamic proximity graphs. By varying the integration time-parameter T, which is the period of infectivity one can give a simple account for some of the differences in the observed contact networks for different diseases, such as smallpox, or AIDS. Our simplistic model also seems to shed some light on the shape of the degree distribution of the measured people-people contact network from the EPISIM data. We certainly do not claim that the simplistic graph integration model above is a good model for dynamic contact graphs. It only contains the essential ingredients for such processes to produce a qualitative agreement with some observations. We expect that further refinements and extensions to this picture, in particular deriving the link-probabilities in the dynamic proximity graph from more realistic contact dynamics should improve the agreement between models and data.

  9. Mechanosensory function of microvilli of the kidney proximal tubule

    PubMed Central

    Du, Zhaopeng; Duan, Yi; Yan, QingShang; Weinstein, Alan M.; Weinbaum, Sheldon; Wang, Tong

    2004-01-01

    Normal variations in glomerular filtration induce proportional changes in proximal tubule Na+ reabsorption. This “glomerulotubular balance” derives from flow dependence of Na+ uptake across luminal cell membranes; however, the underlying physical mechanism is unknown. Our hypothesis is that flow-dependent reabsorption is an autoregulatory mechanism that is independent of neural and hormonal systems. It is signaled by the hydrodynamic torque (bending moment) on epithelial microvilli. Such signals need to be transmitted to the terminal web to modulate Na+-H+-exchange activity. To investigate this hypothesis, we examined Na+ transport and tubular diameter in response to different flow rates during the microperfusion of isolated S2 proximal tubules from mouse kidneys. The data were analyzed by using a mathematical model to estimate the microvillous torque as function of flow. In this model, increases in luminal diameter have the effect of blunting the impact of flow velocity on microvillous shear stress and, thus, microvillous torque. We found that variations in microvillous torque produce nearly identical fractional changes in Na+ reabsorption. Furthermore, the flow-dependent Na+ transport is increased by increasing luminal fluid viscosity, diminished in Na+-H+ exchanger isoform 3 knockout mice, and abolished by nontoxic disruption of the actin cytoskeleton. These data support our hypothesis that the “brush-border” microvilli serve a mechanosensory function in which fluid dynamic torque is transmitted to the actin cytoskeleton and modulates Na+ absorption in kidney proximal tubules. PMID:15319475

  10. Proximate Composition Analysis.

    PubMed

    2016-01-01

    The proximate composition of foods includes moisture, ash, lipid, protein and carbohydrate contents. These food components may be of interest in the food industry for product development, quality control (QC) or regulatory purposes. Analyses used may be rapid methods for QC or more accurate but time-consuming official methods. Sample collection and preparation must be considered carefully to ensure analysis of a homogeneous and representative sample, and to obtain accurate results. Estimation methods of moisture content, ash value, crude lipid, total carbohydrates, starch, total free amino acids and total proteins are put together in a lucid manner.

  11. Proximity networks and epidemics

    NASA Astrophysics Data System (ADS)

    Toroczkai, Zoltán; Guclu, Hasan

    2007-05-01

    Disease spread in most biological populations requires the proximity of agents. In populations where the individuals have spatial mobility, the contact graph is generated by the “collision dynamics” of the agents, and thus the evolution of epidemics couples directly to the spatial dynamics of the population. We first briefly review the properties and the methodology of an agent-based simulation (EPISIMS) to model disease spread in realistic urban dynamic contact networks. Using the data generated by this simulation, we introduce the notion of dynamic proximity networks which takes into account the relevant time-scales for disease spread: contact duration, infectivity period, and rate of contact creation. This approach promises to be a good candidate for a unified treatment of epidemic types that are driven by agent collision dynamics. In particular, using a simple model, we show that it can account for the observed qualitative differences between the degree distributions of contact graphs of diseases with short infectivity period (such as air-transmitted diseases) or long infectivity periods (such as HIV).

  12. Echosonography with proximity sensors

    NASA Astrophysics Data System (ADS)

    Thaisiam, W.; Laithong, T.; Meekhun, S.; Chaiwathyothin, N.; Thanlarp, P.; Danworaphong, S.

    2013-03-01

    We propose the use of a commercial ultrasonic proximity sensor kit for profiling an altitude-varying surface by employing echosonography. The proximity sensor kit, two identical transducers together with its dedicated operating circuit, is used as a profiler for the construction of an image. Ultrasonic pulses are emitted from one of the transducers and received by the other. The time duration between the pulses allows us to determine the traveling distance of each pulse. In the experiment, the circuit is used with the addition of two copper wires for directing the outgoing and incoming signals to an oscilloscope. The time of flight of ultrasonic pulses can thus be determined. Square grids of 5 × 5 cm2 are made from fishing lines, forming pixels in the image. The grids are designed to hold the detection unit in place, about 30 cm above a flat surface. The surface to be imaged is constructed to be height varying and placed on the flat surface underneath the grids. Our result shows that an image of the profiled surface can be created by varying the location of the detection unit along the grid. We also investigate the deviation in relation to the time of flight of the ultrasonic pulse. Such an experiment should be valuable for conveying the concept of ultrasonic imaging to physical and medical science undergraduate students. Due to its simplicity, the setup could be made in any undergraduate laboratory relatively inexpensively and it requires no complex parts. The results illustrate the concept of echosonography.

  13. Some Properties of Fuzzy Soft Proximity Spaces

    PubMed Central

    Demir, İzzettin; Özbakır, Oya Bedre

    2015-01-01

    We study the fuzzy soft proximity spaces in Katsaras's sense. First, we show how a fuzzy soft topology is derived from a fuzzy soft proximity. Also, we define the notion of fuzzy soft δ-neighborhood in the fuzzy soft proximity space which offers an alternative approach to the study of fuzzy soft proximity spaces. Later, we obtain the initial fuzzy soft proximity determined by a family of fuzzy soft proximities. Finally, we investigate relationship between fuzzy soft proximities and proximities. PMID:25793224

  14. Hirayama Disease with Proximal Involvement.

    PubMed

    Kim, Jinil; Kim, Yuntae; Kim, Sooa; Oh, Kiyoung

    2016-10-01

    Hirayama disease is a slowly progressing benign motor neuron disease that affects the distal upper limb. A 29-year-old man visited the hospital with a 1-year history of weakened left proximal upper limb. He was diagnosed with Hirayama disease 9 years ago, while there was no further progression of the muscle weakness afterward. Atrophy and weakness was detected in proximal upper limb muscles. Magnetic resonance imaging and somatosensory evoked potentials were normal. Needle electromyography showed abnormal findings in proximal upper limb muscles. Our patient had Hirayama disease involving the proximal portion through secondary progression. Clinical manifestation and accurate electromyography may be useful for diagnosis. Rare cases with progression patterns as described here are helpful and have clinical meaning for clinicians. PMID:27550499

  15. Hirayama Disease with Proximal Involvement

    PubMed Central

    2016-01-01

    Hirayama disease is a slowly progressing benign motor neuron disease that affects the distal upper limb. A 29-year-old man visited the hospital with a 1-year history of weakened left proximal upper limb. He was diagnosed with Hirayama disease 9 years ago, while there was no further progression of the muscle weakness afterward. Atrophy and weakness was detected in proximal upper limb muscles. Magnetic resonance imaging and somatosensory evoked potentials were normal. Needle electromyography showed abnormal findings in proximal upper limb muscles. Our patient had Hirayama disease involving the proximal portion through secondary progression. Clinical manifestation and accurate electromyography may be useful for diagnosis. Rare cases with progression patterns as described here are helpful and have clinical meaning for clinicians. PMID:27550499

  16. 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...

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

    PubMed

    Weinstein, A M

    1983-11-01

    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.

  18. [Management of proximal ureteral stones].

    PubMed

    Lechevallier, E; Taxer, O; Saussine, C

    2008-12-01

    Proximal ureteral stone less than 4-6mm may initially be treated by surveillance. Generally, extracorporeal shockwave lithotripsy (ESWL) is the first line treatment for proximal ureteral stones, specially for stones less than 1cm. For stones greater than 1cm, the results of ureteroscopy (URS) are better than the results of ESWL and in these cases URS may be an option. In case of failure of ESWL, URS can be proposed. URS can be the first line treatment in case of severe ureteral obstruction with no urinary infection. Proximal ureteroscopy must be careful because severe complications are not infrequent. Open surgery has very rare indication. Metabolic check-up and annually follow-up with at least a renal imaging at three months are recommended.

  19. Cubesat Proximity Operations Demonstration (CPOD)

    NASA Technical Reports Server (NTRS)

    Villa, Marco; Martinez, Andres; Petro, Andrew

    2015-01-01

    The CubeSat Proximity Operations Demonstration (CPOD) project will demonstrate rendezvous, proximity operations and docking (RPOD) using two 3-unit (3U) CubeSats. Each CubeSat is a satellite with the dimensions 4 inches x 4 inches x 13 inches (10 centimeters x 10 centimeters x 33 centimeters) and weighing approximately 11 pounds (5 kilograms). This flight demonstration will validate and characterize many new miniature low-power proximity operations technologies applicable to future missions. This mission will advance the state of the art in nanosatellite attitude determination,navigation and control systems, in addition to demonstrating relative navigation capabilities.The two CPOD satellites are scheduled to be launched together to low-Earth orbit no earlier than Dec. 1, 2015.

  20. Proximal Rectus Femoris Avulsion Repair.

    PubMed

    Dean, Chase S; Arbeloa-Gutierrez, Lucas; Chahla, Jorge; Pascual-Garrido, Cecilia

    2016-06-01

    Proximal rectus femoris tendon avulsions are rare and occur mostly in male athletes. Currently, the standard of care for complete tendinous avulsions of the direct arm of the rectus femoris is nonoperative treatment. However, surgical repair may be considered in high-level athletes who have a high demand for repetitive hip flexion performed in an explosive manner or in patients in whom nonoperative treatment has failed. The purpose of this technical note is to describe the method for surgical repair of the proximal direct arm of the rectus femoris to its origin at the anterior inferior iliac spine using suture anchors. PMID:27656376

  1. 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.

  2. Geographic Proximity and Enrollment Competition.

    ERIC Educational Resources Information Center

    Zammuto, Raymond F.

    The use of a measure of geographic proximity to help explain enrollment competition among postsecondary institutions was investigated. The measure, the number of miles between institutions, was obtained by determining the longitude and latitude coordinates for about 99% of the schools in the Higher Education General Information System universe.…

  3. Na+ recirculation and isosmotic transport.

    PubMed

    Larsen, E H; Møbjerg, N

    2006-01-01

    The Na(+) recirculation theory for solute-coupled fluid absorption is an expansion of the local osmosis concept introduced by Curran and analyzed by Diamond & Bossert. Based on studies on small intestine the theory assumes that the observed recirculation of Na(+) serves regulation of the osmolarity of the absorbate. Mathematical modeling reproducing bioelectric and hydrosmotic properties of small intestine and proximal tubule, respectively, predicts a significant range of observations such as isosmotic transport, hyposmotic transport, solvent drag, anomalous solvent drag, the residual hydraulic permeability in proximal tubule of AQP1 (-/-) mice, and the inverse relationship between hydraulic permeability and the concentration difference needed to reverse transepithelial water flow. The model reproduces the volume responses of cells and lateral intercellular space (lis) following replacement of luminal NaCl by sucrose as well as the linear dependence of volume absorption on luminal NaCl concentration. Analysis of solvent drag on Na(+) in tight junctions provides explanation for the surprisingly high metabolic efficiency of Na(+) reabsorption. The model predicts and explains low metabolic efficiency in diluted external baths. Hyperosmolarity of lis is governed by the hydraulic permeability of the apical plasma membrane and tight junction with 6-7 mOsm in small intestine and < or = 1 mOsm in proximal tubule. Truly isosmotic transport demands a Na(+) recirculation of 50-70% in small intestine but might be barely measurable in proximal tubule. The model fails to reproduce a certain type of observations: The reduced volume absorption at transepithelial osmotic equilibrium in AQP1 knockout mice, and the stimulated water absorption by gallbladder in diluted external solutions. Thus, it indicates cellular regulation of apical Na(+) uptake, which is not included in the mathematical treatment. PMID:17206513

  4. Na+ recirculation and isosmotic transport.

    PubMed

    Larsen, E H; Møbjerg, N

    2006-01-01

    The Na(+) recirculation theory for solute-coupled fluid absorption is an expansion of the local osmosis concept introduced by Curran and analyzed by Diamond & Bossert. Based on studies on small intestine the theory assumes that the observed recirculation of Na(+) serves regulation of the osmolarity of the absorbate. Mathematical modeling reproducing bioelectric and hydrosmotic properties of small intestine and proximal tubule, respectively, predicts a significant range of observations such as isosmotic transport, hyposmotic transport, solvent drag, anomalous solvent drag, the residual hydraulic permeability in proximal tubule of AQP1 (-/-) mice, and the inverse relationship between hydraulic permeability and the concentration difference needed to reverse transepithelial water flow. The model reproduces the volume responses of cells and lateral intercellular space (lis) following replacement of luminal NaCl by sucrose as well as the linear dependence of volume absorption on luminal NaCl concentration. Analysis of solvent drag on Na(+) in tight junctions provides explanation for the surprisingly high metabolic efficiency of Na(+) reabsorption. The model predicts and explains low metabolic efficiency in diluted external baths. Hyperosmolarity of lis is governed by the hydraulic permeability of the apical plasma membrane and tight junction with 6-7 mOsm in small intestine and < or = 1 mOsm in proximal tubule. Truly isosmotic transport demands a Na(+) recirculation of 50-70% in small intestine but might be barely measurable in proximal tubule. The model fails to reproduce a certain type of observations: The reduced volume absorption at transepithelial osmotic equilibrium in AQP1 knockout mice, and the stimulated water absorption by gallbladder in diluted external solutions. Thus, it indicates cellular regulation of apical Na(+) uptake, which is not included in the mathematical treatment.

  5. Foot anomalies and proximal symphalangism.

    PubMed

    Shaw, Lauren; McCaul, Janet; Irwin, Greg J; Huntley, James S

    2012-09-01

    We report the case of a 2-week-old girl born at term (by vaginal delivery and without antenatal or perinatal events) who was referred as having "bilateral talipes and bilateral proximal symphalangism of little and ring fingers." The "talipes" was atypical with marked equinus and varus, but no cavus or adductus of the midfoot. Her mother had both symphalangism (absence of proximal interphalangeal joints) of middle, ring, and little fingers bilaterally and fixed pes planus with a rigid fixed hindfoot-and these deformities had also been present from birth. The maternal grandmother was similarly affected. However, the neonatal subject has an unaffected older sibling; maternal siblings are also unaffected. The three affected people did not have other obvious musculoskeletal abnormalities. Because of the coalitions, the child's atypical talipes was managed by a modified Kite's procedure. Symphalangism-coalition syndromes may be associated with conductive deafness because of fusion of the auditory ossicles.

  6. Fractures of the proximal humerus.

    PubMed

    Brorson, Stig

    2013-10-01

    Fractures of the proximal humerus have been diagnosed and managed since the earliest known surgical texts. For more than four millennia the preferred treatment was forceful traction, closed reduction, and immobilization with linen soaked in combinations of oil, honey, alum, wine, or cerate. The bandages were further supported by splints made of wood or coarse grass. Healing was expected in forty days. Different fracture patterns have been discussed and classified since Ancient Greece. Current classification of proximal humeral fractures mainly relies on the classifications proposed by Charles Neer and the AO/OTA classification. Since the late 1980's it has been known that intra- and inter-observer variation was high within the two systems. I conducted a series of observer studies to qualify the disagreement further and to study to what extent improvement of agreement could be obtained. No clinically significant differences in observer agreement were found at different levels of clinical experience, by reducing the number of categories, or by adding high quality radiographs, CT or 3D CT scans. A consistently low agreement on the Neer classification within and between untrained orthopaedic doctors was found. However, we also found that inter-observer agreement on treatment recommendation was higher than the agreement on the Neer classification. In a randomized trial we found that agreement could improve significantly by training of doctors, especially among specialists. However, classification of proximal humeral fractures remains a challenge for the conduct, reporting, and interpretation of clinical trials. The evidence for the benefits of surgery in complex fractures of the proximal humerus is weak. In three systematic reviews I studied the outcome after locking plate osteosynthesis or reverse arthroplasty in complex fractures patterns. No randomized trials or well-conducted comparative studies were identified. High failure rates suggest that the use of these

  7. Micropower RF material proximity sensor

    DOEpatents

    McEwan, Thomas E.

    1998-01-01

    A level detector or proximity detector for materials capable of sensing through plastic container walls or encapsulating materials is of the sensor. Thus, it can be used in corrosive environments, as well as in a wide variety of applications. An antenna has a characteristic impedance which depends on the materials in proximity to the antenna. An RF oscillator, which includes the antenna and is based on a single transistor in a Colpitt's configuration, produces an oscillating signal. A detector is coupled to the oscillator which signals changes in the oscillating signal caused by changes in the materials in proximity to the antenna. The oscillator is turned on and off at a pulse repetition frequency with a low duty cycle to conserve power. The antenna consists of a straight monopole about one-quarter wavelength long at the nominal frequency of the oscillator. The antenna may be horizontally disposed on a container and very accurately detects the fill level within the container as the material inside the container reaches the level of the antenna.

  8. Micropower RF material proximity sensor

    DOEpatents

    McEwan, T.E.

    1998-11-10

    A level detector or proximity detector for materials capable of sensing through plastic container walls or encapsulating materials is disclosed. Thus, it can be used in corrosive environments, as well as in a wide variety of applications. An antenna has a characteristic impedance which depends on the materials in proximity to the antenna. An RF oscillator, which includes the antenna and is based on a single transistor in a Colpitt`s configuration, produces an oscillating signal. A detector is coupled to the oscillator which signals changes in the oscillating signal caused by changes in the materials in proximity to the antenna. The oscillator is turned on and off at a pulse repetition frequency with a low duty cycle to conserve power. The antenna consists of a straight monopole about one-quarter wavelength long at the nominal frequency of the oscillator. The antenna may be horizontally disposed on a container and very accurately detects the fill level within the container as the material inside the container reaches the level of the antenna. 5 figs.

  9. Plating of proximal humeral fractures.

    PubMed

    Martetschläger, Frank; Siebenlist, Sebastian; Weier, Michael; Sandmann, Gunther; Ahrens, Philipp; Braun, Karl; Elser, Florian; Stöckle, Ulrich; Freude, Thomas

    2012-11-01

    The optimal treatment for proximal humeral fractures is controversial. Few data exist concerning the influence of the surgical approach on the outcome. The purpose of this study was to evaluate the clinical and radiological outcomes of proximal humeral fractures treated with locking plate fixation through a deltopectoral vs an anterolateral deltoid-splitting approach. Of 86 patients who met the inclusion criteria, 70 were available for follow-up examination. Thirty-three patients were treated through a deltopectoral approach and 37 through an anterolateral deltoid-splitting approach. In all cases, open reduction and internal fixation with a PHILOS locking plate (Synthes, Umkirch, Germany) was performed. Clinical follow-up included evaluation of pain, shoulder mobility, and strength. Constant score and Disabilities of the Arm, Shoulder and Hand (DASH) score were assessed. A clinical neurological examination of the axillary nerve was also performed. Consolidation, reduction, and appearance of head necrosis were evaluated radiographically. After a mean follow-up of 33 months, Constant scores, DASH scores, and American Shoulder and Elbow Surgeons scores showed no significant differences between the groups. Clinical neurologic examination of the axillary nerve revealed no obvious damage to the nerve in either group. Deltopectoral and anterolateral detoid-splitting approaches for plate fixation of proximal humeral fractures are safe and provide similar clinical outcomes. The results of this study suggest that the approach can be chosen according to surgeon preference.

  10. Proximate and polyphenolic characterization of cranberry pomace

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The proximate composition and identification and quantification of polyphenolic compounds in dried cranberry pomace were determined. Proximate analysis was conducted based on AOAC methods for moisture, protein, fat, and ash. Total carbohydrates were determined by the difference method. Polyphenolic ...

  11. 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.

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

    PubMed Central

    Vallon, Volker; Edwards, Aurélie

    2015-01-01

    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

  13. Coupled water transport by rat proximal tubule.

    PubMed

    Green, R; Giebisch, G; Unwin, R; Weinstein, A M

    1991-12-01

    Simultaneous microperfusion of proximal tubules and peritubular capillaries in kidneys of rats anesthetized with Inactin was used to examine water reabsorption by this epithelium. Osmolality of the luminal solution was varied with changes in NaCl concentration and by the addition of raffinose. Capillary perfusates contained either low (2 g/dl) or high (16 g/dl) concentrations of albumin. We used low-bicarbonate perfusates for both lumen and capillary so that we might apply the nonequilibrium thermodynamic model of transport for a single solute (NaCl) to interpret our observations. Linear regression with the volume flux equation Jv = -Lp delta II - Lp sigma delta C + Jav (where Jv is volume flux, Lp is hydraulic conductance, delta II is oncotic force, sigma is osmotic reflection coefficient, delta C is salt concentration difference, and Jav is the component of Jv not attributed to transepithelial hydrostatic or osmotic forces) revealed a tubule water permeability (Pf = 0.11 +/- 0.01 cm/s) and a sigma (0.74 +/- 0.08) in agreement with previous determinations. These transport parameters were unaffected by changes in peritubular protein. We also found that Jav was substantial, approximately three-fourths of the rate of isotonic transport under these perfusion conditions. Further, this component of water transport nearly doubled with the transition from low- to high-protein peritubular capillary perfusion. When expressed as a capacity for water reabsorption against an osmotic gradient, the salt concentration differences required to null volume flux were 13.2 +/- 2.4 and 29.4 +/- 4.0 mosmol/kgH2O under low and high peritubular protein. Our data suggest that this protein effect is, most likely, an increase in solute transport by the tubule epithelial cells. PMID:1750518

  14. Proximal Biceps in Overhead Athletes.

    PubMed

    Chalmers, Peter N; Verma, Nikhil N

    2016-01-01

    The proximal long head of the biceps tendon and its attachment at the superior glenoid tubercle and labrum are subject to a spectrum of disorders in overhead athletes. Biceps disorders are commonly characterized by intermittent anterior or deep-seated shoulder pain exacerbated by activity. Diagnosis is reached via various physical examination maneuvers; MRI can be uncertain. Nonsteroidal anti-inflammatory medications, targeted ultrasound-guided corticosteroid injections, and supervised physical therapy are the mainstays of nonoperative treatment. Operative treatment, which remains controversial, provides reliable pain relief, restoration of function for activities of daily living, and low complication rates, but return to play can be unpredictable.

  15. Biomass proximate analysis using thermogravimetry.

    PubMed

    García, Roberto; Pizarro, Consuelo; Lavín, Antonio G; Bueno, Julio L

    2013-07-01

    This work proposes a 25 min-last thermogravimetric method as a tool to determine biomass sample's proximate analysis data (moisture, ash, volatile matter and fixed carbon contents) just by direct measure of weight changes on each sample's TG chart. Compared with international standards commonly used to that aim, TG is a faster and easier to develop technique. Obtained results were satisfactory, with AEE under 6% for moisture and volatile matter, close to 10% for fixed carbon determination and AAD of 1.6 points for ash content.

  16. 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

  17. Proximate and elemental analysis of infant formula.

    PubMed

    Tanner, J T

    1982-11-01

    The Nutrient Surveillance Branch has been conducting a survey of infant formula products for Fiscal Year 1981. Each product has been carefully analyzed and the results compared to the label declaration and the minimum-maximum limits specified by the American Academy of Pediatrics' Committee on Nutrition (CON/AAP). Proximate and elemental analyses were made. Protein, fat, ash, and total solids (moisture) were determined by AOAC methods. Osmolality, density, and fatty acids (linoleic) were also determined. Carbohydrates were calculated by difference and caloric content was calculated by using the general Atwater factors. Elemental analysis for Ca, P, Mg, Fe, Zn, Cu, Mn, Na, and K were performed by induction coupled plasma absorption spectroscopy. Chloride was assayed by potentiometric titration with AgNO3. A summary of the findings from the infant formula survey have been compared with CON/AAP recommendations. In general, there were only a few exceptions where the label claims and the CON/AAP requirements were not met. However, in none of these cases was the difference considered to be of public health significance.

  18. Proximal bodies in hypersonic flow

    SciTech Connect

    Deiterding, Ralf; Laurence, Stuart J; Hornung, Hans G

    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.

  19. Protein Neighbors and Proximity Proteomics*

    PubMed Central

    Rees, Johanna S.; Li, Xue-Wen; Perrett, Sarah; Lilley, Kathryn S.; Jackson, Antony P.

    2015-01-01

    Within cells, proteins can co-assemble into functionally integrated and spatially restricted multicomponent complexes. Often, the affinities between individual proteins are relatively weak, and proteins within such clusters may interact only indirectly with many of their other protein neighbors. This makes proteomic characterization difficult using methods such as immunoprecipitation or cross-linking. Recently, several groups have described the use of enzyme-catalyzed proximity labeling reagents that covalently tag the neighbors of a targeted protein with a small molecule such as fluorescein or biotin. The modified proteins can then be isolated by standard pulldown methods and identified by mass spectrometry. Here we will describe the techniques as well as their similarities and differences. We discuss their applications both to study protein assemblies and to provide a new way for characterizing organelle proteomes. We stress the importance of proteomic quantitation and independent target validation in such experiments. Furthermore, we suggest that there are biophysical and cell-biological principles that dictate the appropriateness of enzyme-catalyzed proximity labeling methods to address particular biological questions of interest. PMID:26355100

  20. Ash Aggregates in Proximal Settings

    NASA Astrophysics Data System (ADS)

    Porritt, L. A.; Russell, K.

    2012-12-01

    Ash aggregates are thought to have formed within and been deposited by the eruption column and plume and dilute density currents and their associated ash clouds. Moist, turbulent ash clouds are considered critical to ash aggregate formation by facilitating both collision and adhesion of particles. Consequently, they are most commonly found in distal deposits. Proximal deposits containing ash aggregates are less commonly observed but do occur. Here we describe two occurrences of vent proximal ash aggregate-rich deposits; the first within a kimberlite pipe where coated ash pellets and accretionary lapilli are found within the intra-vent sequence; and the second in a glaciovolcanic setting where cored pellets (armoured lapilli) occur within <1 km of the vent. The deposits within the A418 pipe, Diavik Diamond Mine, Canada, are the residual deposits within the conduit and vent of the volcano and are characterised by an abundance of ash aggregates. Coated ash pellets are dominant but are followed in abundance by ash pellets, accretionary lapilli and rare cored pellets. The coated ash pellets typically range from 1 - 5 mm in diameter and have core to rim ratios of approximately 10:1. The formation and preservation of these aggregates elucidates the style and nature of the explosive phase of kimberlite eruption at A418 (and other pipes?). First, these pyroclasts dictate the intensity of the kimberlite eruption; it must be energetic enough to cause intense fragmentation of the kimberlite to produce a substantial volume of very fine ash (<62 μm). Secondly, the ash aggregates indicate the involvement of moisture coupled with the presence of dilute expanded eruption clouds. The structure and distribution of these deposits throughout the kimberlite conduit demand that aggregation and deposition operate entirely within the confines of the vent; this indicates that aggregation is a rapid process. Ash aggregates within glaciovolcanic sequences are also rarely documented. The

  1. Proximity effect correction sensitivity analysis

    NASA Astrophysics Data System (ADS)

    Zepka, Alex; Zimmermann, Rainer; Hoppe, Wolfgang; Schulz, Martin

    2010-05-01

    Determining the quality of a proximity effect correction (PEC) is often done via 1-dimensional measurements such as: CD deviations from target, corner rounding, or line-end shortening. An alternative approach would compare the entire perimeter of the exposed shape and its original design. Unfortunately, this is not a viable solution as there is a practical limit to the number of metrology measurements that can be done in a reasonable amount of time. In this paper we make use of simulated results and introduce a method which may be considered complementary to the standard way of PEC qualification. It compares simulated contours with the target layout via a Boolean XOR operation with the area of the XOR differences providing a direct measure of how close a corrected layout approximates the target.

  2. Proximity and emergency department use

    PubMed Central

    Bergeron, Patrick; Courteau, Josiane; Vanasse, Alain

    2015-01-01

    Abstract Objective To determine if geographic proximity to an emergency department (ED) is related to ED use in a metropolitan population of patients with cardiovascular risk factors. Design Population-based, retrospective cohort study. Setting The census metropolitan area of Montreal, Que. Participants Cohort of 99 400 patients with diabetes, hypertension, or dyslipidemia in 2007 without a history of cardiovascular disease. Each patient was spatially referred to 1 of 5857 dissemination areas (DAs). Main outcome measures Annual number of visits to an ED with respect to the distance between the centroid of a patient’s DA and the closest ED, controlling for age, sex, comorbidities, and neighbourhood immigration, social, and material characteristics. Multilevel logistic and negative binomial regressions were used to determine if the proximity to the closest ED was related to ED use, frequent ED use (≥ 4 visits in a year), and number of ED visits. Results A total of 25 889 (26.0%) patients in the cohort visited an ED at least once during a 1-year period, among which 4563 (4.6%) were frequent users with at least 4 visits. These frequent users were responsible for 28 249 (45.5%) of all 62 021 visits to EDs. The distance between a DA and its closest ED was significantly and negatively correlated with ED use (P < .001), even after controlling for confounding variables. Patients living in a DA close to an ED were also more likely to be frequent users, but the extent of use among them (range from 4 to 82 ED visits) was not related to the distance to the closest ED. Conclusion These results suggest that patients at risk of cardiovascular disease living in a metropolitan area are more likely to seek a medical encounter at the ED if they live closer to it. PMID:26505061

  3. Isovolumetric regulation of renal proximal tubules in hypotonic medium.

    PubMed

    Lohr, J W

    1990-01-01

    Isolated nonperfused proximal tubules maintained their cell volume at a constant level (isovolumetric regulation, IVR), when osmolality of the bathing medium was gradually decreased from 290 to 190 mosm at 1.5 and 5.0 mosm/min. Hypotonic IVR was blocked by inhibiting the Na(+)-K+ pump with ouabain (10(-4) M) when osmolality was decreased at 1.5 or 5 mosm/min. Concentration-dependent inhibition of cell volume maintenance was observed in the presence of the K+ channel blocker barium (10(-3)-10(-2) M) when osmolality decreased at 5 mosm/min. Quinine (10(-3) M), another K+ channel blocker, also inhibited IVR at osmolality decreases of 1.5 and 5 mosm/min. These results suggest that the maintenance of constant cell volume during gradual hypoosmotic exposure involves mechanisms that depend on intact Na-K-ATPase and the controlled loss of intracellular K+.

  4. Range gated strip proximity sensor

    DOEpatents

    McEwan, Thomas E.

    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.

  5. 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.

  6. Proximal Priority Laser Therapy: PPLT

    NASA Astrophysics Data System (ADS)

    Ohshiro, Toshio

    2004-09-01

    The author has, in the past, classified treatment methods for pain geometrically as point, line, two-dimensional, three-dimensional treatment and has used these over the years. However as a practitioner of western medicine, the author originally treated pain only directed at the painful site, and encountered cases where local treatment did not suffice. The author proved with SPECT and the Rand Phantom that treating the neck which is the midpoint of the brain, the center of the nervous system and the heart, the center of circulation, increased cerebral blood flow and also that laser emitted to neck will reach the spinal chord no matter from where on the neck the laser is emitted. From such research and 25 years of clinical experience, the author has created an anatomy based, systemic treatment method called the Proximal Priority Laser Therapy (PPLT) where not only the cerebral cortex, spinal chord and peripheral nerves are treated but also the tracts of blood vessels and lymph ducts are treated as well. Treatment method and cases are presented herein.

  7. Proximal Participation: A Pathway into Work

    ERIC Educational Resources Information Center

    Chan, Selena

    2013-01-01

    In a longitudinal case study of apprentices, the term proximal participation was coined to describe the entry process of young people, with unclear career destinations, into the trade of baking. This article unravels the significance of proximal participation in the decision-making processes of young people who enter a trade through initial…

  8. Grouping by proximity in haptic contour detection.

    PubMed

    Overvliet, Krista E; Krampe, Ralf Th; Wagemans, Johan

    2013-01-01

    We investigated the applicability of the Gestalt principle of perceptual grouping by proximity in the haptic modality. To do so, we investigated the influence of element proximity on haptic contour detection. In the course of four sessions ten participants performed a haptic contour detection task in which they freely explored a haptic random dot display that contained a contour in 50% of the trials. A contour was defined by a higher density of elements (raised dots), relative to the background surface. Proximity of the contour elements as well as the average proximity of background elements was systematically varied. We hypothesized that if proximity of contour elements influences haptic contour detection, detection will be more likely when contour elements are in closer proximity. This should be irrespective of the ratio with the proximity of the background elements. Results showed indeed that the closer the contour elements were, the higher the detection rates. Moreover, this was the case independent of the contour/background ratio. We conclude that the Gestalt law of proximity applies to haptic contour detection.

  9. Proximate Sources of Collective Teacher Efficacy

    ERIC Educational Resources Information Center

    Adams, Curt M.; Forsyth, Patrick B.

    2006-01-01

    Purpose: Recent scholarship has augmented Bandura's theory underlying efficacy formation by pointing to more proximate sources of efficacy information involved in forming collective teacher efficacy. These proximate sources of efficacy information theoretically shape a teacher's perception of the teaching context, operationalizing the difficulty…

  10. [Robot-assisted coelioscopic proximal tubal reanastomosis].

    PubMed

    Carbonnel, M; Roulot, A; Fay, S; Ayoubi, J-M

    2013-01-01

    We report two cases of robot-assisted coelioscopic proximal tubal reanastomosis after proximal tubal ligature. Patients were aged 43 and 34 years respectively and had previously undergone proximal tubal ligation by coagulation section at 37 years of age for the first patient, and by Filshie clip at 24 years for the second one. Both had regular menstrual cycles and their ovarian reserve was good. Their partners were presenting with normal sperm criteria. Proximal tubal reanastomosis was carried out in September 2010 by robotic coelioscopy with five extramucous vicryl 5-0 stitches on each tube and positive blue testing. Total durations of the interventions were 200 and 220minutes respectively. Postoperative outcomes were simple and patients had spontaneous pregnancy at 4 and 2.5 months respectively. Both pregnancies show normal progress currently. This is a contribution to literature data meant to determine the role of robotics in proximal tubal reanastomosis. PMID:22521989

  11. 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.

  12. Fast optical proximity correction: analytical method

    NASA Astrophysics Data System (ADS)

    Shioiri, Satomi; Tanabe, Hiroyoshi

    1995-05-01

    In automating optical proximity correction, calculation speed becomes important. In this paper we present a novel method for calculating proximity corrected features analytically. The calculation will take only several times the amount it takes to calculate intensity of one point on wafer. Therefore, the calculation will become extremely faster than conventional repetitive aerial image calculations. This method is applied to a simple periodic pattern. The simulated results show great improvement on linearity after correction and have proved the effectiveness of this analytical method.

  13. [Proximity, intimacy and promiscuity in care].

    PubMed

    Flicourt, Nadia

    2015-04-01

    Lying at the heart of the intimacy of the other person, the nature of care supposes that the caregiver identifies the components resulting from the proximity and the invasion of the patient's personal space, where perceptions and representations give rise to reactive emotions and behaviour. Between modesty and nudity, proximity and promiscuity, caregivers have to adjust their approach of proper care, limiting the risks of intrusion. PMID:26043630

  14. Proximity sensor system development. CRADA final report

    SciTech Connect

    Haley, D.C.; Pigoski, T.M.

    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.

  15. Locking plates in proximal humerus fractures.

    PubMed

    Strohm, P C; Helwig, P; Konrad, G; Südkamp, N P

    2007-12-01

    It is well known that proximal humerus fractures are among the three most frequent fracture types. Epidemiological invetsigations show that in people elder than 60 years the fracture of the proximal humerus is more frequent than fractures of the hip region (17). Over the last decades several techniques have been applied for treatment of proximal humerus fractures. Widely accepted is the initiation of a conservative treatment regimen for undisplaced fractures, however, the standard treatment for displaced fractures, especially three and four part fractures, is still the center of scientific debate. Many different implants have been tested and investigated, thus demonstrating lack of sufficient results. Over the last years the development of angle stable, locking implants started and clinical studies demonstrated encouraging results. In our clinic the locking proximal humerus plate and the PHILOS plate advanced to the implant of choice for treatment of displaced proximal humerus fractures. There are still cases of implant failure and humerus head necrosis, but most of these complications were caused by the fracture type and not an implant specific problem. However the overall results with these new implants are encouraging. Key words: locking plates, proximal humerus fracture, humerus, humerus fracture, PHILOS, PHP.

  16. Visualization of Calcium Dynamics in Kidney Proximal Tubules.

    PubMed

    Szebényi, Kornélia; Füredi, András; Kolacsek, Orsolya; Csohány, Rózsa; Prókai, Ágnes; Kis-Petik, Katalin; Szabó, Attila; Bősze, Zsuzsanna; Bender, Balázs; Tóvári, József; Enyedi, Ágnes; Orbán, Tamás I; Apáti, Ágota; Sarkadi, Balázs

    2015-11-01

    Intrarenal changes in cytoplasmic calcium levels have a key role in determining pathologic and pharmacologic responses in major kidney diseases. However, cell-specific delivery of calcium-sensitive probes in vivo remains problematic. We generated a transgenic rat stably expressing the green fluorescent protein-calmodulin-based genetically encoded calcium indicator (GCaMP2) predominantly in the kidney proximal tubules. The transposon-based method used allowed the generation of homozygous transgenic rats containing one copy of the transgene per allele with a defined insertion pattern, without genetic or phenotypic alterations. We applied in vitro confocal and in vivo two-photon microscopy to examine basal calcium levels and ligand- and drug-induced alterations in these levels in proximal tubular epithelial cells. Notably, renal ischemia induced a transient increase in cellular calcium, and reperfusion resulted in a secondary calcium load, which was significantly decreased by systemic administration of specific blockers of the angiotensin receptor and the Na-Ca exchanger. The parallel examination of in vivo cellular calcium dynamics and renal circulation by fluorescent probes opens new possibilities for physiologic and pharmacologic investigations.

  17. New Advances in the Study of the Proximal Point Algorithm

    NASA Astrophysics Data System (ADS)

    Moroşanu, Gheorghe

    2010-09-01

    Consider in a real Hilbert space H the inexact, Halpern-type, proximal point algorithm xn+1 = αnu+(1-αn)Jβnxn+en, n = 0,1,…, (H—PPA) where u, x∈H are given points, Jβn = (I+βna) for a given maximal monotone operator A, and (en) is the error sequence, under new assumptions on αn∈(0,1) and βn∈(0,1). Several strong convergence results for the H—PPA are presented under the general condition that the error sequence converges strongly to zero, thus improving the classical Rockafellar's summability condition on (‖en‖) that has been extensively used so far for different versions of the proximal point algorithm. Our results extend and improve some recent ones. These results can be applied to approximate minimizers of convex functionals. Convergence rate estimates are established for a sequence approximating the minimum value of such a functional.

  18. Quantitive analysis of the proximity effect in optical lithographic process

    NASA Astrophysics Data System (ADS)

    Bae, Sang-Man; Kim, Hung-Eil; Ham, Young-Mog; Moon, Seung-Chan; Choi, Soo-Han

    1994-05-01

    As the density of VLSI circuits increases, the proximity effect has been one of the critical issues in optical lithography. In general, the linewidth difference between dense and isolated patterns corresponds to 0.08 micrometers when a conventional i-line single resist process using a 0.54 NA is applied to the half-micron geometry on a flat wafer. Therefore, this linewidth difference has significantly affected the process stability in the real process applications. This paper describes the dependency of the proximity effects on the pattern size, line and space duty ratio, kinds of substrate film, defocus effect during exposure, and resist process conditions related to the variation of the resist thickness and develop time. Critical dimension (CD) deviation caused by the different latent image contrast is also experimentally monitored using two different photoresists. A simulation is performed for the purpose of obtaining the optimum resist thickness to reduce CD difference caused by the variations of resist thickness in the real topography.

  19. Proximal Junctional Kyphosis: Diagnosis, Pathogenesis, and Treatment

    PubMed Central

    Lee, Jaewon

    2016-01-01

    Proximal junctional kyphosis (PJK) is a common radiographic finding after long spinal fusion. A number of studies on the causes, risk factors, prevention, and treatment of PJK have been conducted. However, no clear definition of PJK has been established. In this paper, we aimed to clarify the diagnosis, prevention, and treatment of PJK by reviewing relevant papers that have been published to date. A literature search was conducted on PubMed using "proximal junctional", "proximal junctional kyphosis", and "proximal junctional failure" as search keywords. Only studies that were published in English were included in this study. The incidence of PJK ranges from 5% to 46%, and it has been reported that 66% of cases occur 3 months after surgery and approximately 80% occur within 18 months. A number of studies have reported that there is no significantly different clinical outcome between PJK patients and non-PJK patients. One study showed that PJK patients expressed more pain than non-PJK patients. However, recent studies focused on proximal junctional failure (PJF), which is accepted as a severe form of PJK. PJF showed significant adverse impact in clinical aspect such as pain, neurologic deficit, ambulatory difficulties, and social isolation. Numerous previous studies have identified various risk factors and reported on the treatment and prevention of PJK. Based on these studies, we determined the clinical significance and impact of PJK. In addition, it is important to find a strategic approach to the proper treatment of PJK. PMID:27340542

  20. A mathematical model of rat proximal tubule and loop of Henle

    PubMed Central

    2015-01-01

    Proximal tubule and loop of Henle function are coupled, with proximal transport determining loop fluid composition, and loop transport modulating glomerular filtration via tubuloglomerular feedback (TGF). To examine this interaction, we begin with published models of the superficial rat proximal convoluted tubule (PCT; including flow-dependent transport in a compliant tubule), and the rat thick ascending Henle limb (AHL). Transport parameters for this PCT are scaled down to represent the proximal straight tubule (PST), which is connected to the thick AHL via a short descending limb. Transport parameters for superficial PCT and PST are scaled up for a juxtamedullary nephron, and connected to AHL via outer and inner medullary descending limbs, and inner medullary thin AHL. Medullary interstitial solute concentrations are specified. End-AHL hydrostatic pressure is determined by distal nephron flow resistance, and the TGF signal is represented as a linear function of end-AHL cytosolic Cl concentration. These two distal conditions required iterative solution of the model. Model calculations capture inner medullary countercurrent flux of urea, and also suggest the presence of an outer medullary countercurrent flux of ammonia, with reabsorption in AHL and secretion in PST. For a realistically strong TGF signal, there is the expected homeostatic impact on distal flows, and in addition, a homeostatic effect on proximal tubule pressure. The model glycosuria threshold is compatible with rat data, and predicted glucose excretion with selective 1Na+:1glucose cotransporter (SGLT2) inhibition comports with observations in the mouse. Model calculations suggest that enhanced proximal tubule Na+ reabsorption during hyperglycemia is sufficient to activate TGF and contribute to diabetic hyperfiltration. PMID:25694479

  1. Effects of VIP and NO on the motor activity of vascularly perfused rat proximal colon.

    PubMed

    Kumano, K; Fujimura, M; Oshima, S; Yamamoto, H; Hayashi, N; Nakamura, T; Fujimiya, M

    2001-01-01

    The effects of vasoactive intestinal polypeptide (VIP) and nitric oxide (NO) on the motor activity of the rat proximal colon were examined in an ex vivo model of vascularly perfused rat proximal colon. VIP reduced motor activity and this inhibitory effect was not altered by either atropine, hexamethonium, tetrodotoxin (TTX) nor TTX plus acetylcholine (ACh), but was completely antagonized by NO synthase inhibitor N(G)-nitro-L-arginine (L-NA) and by VIP receptor antagonist, VIP(10-28). These results suggest that VIP may exert a direct inhibitory effect on the motor activity of the rat proximal colon via a VIP receptor located on the smooth muscle and this effect is mediated by NO but not by cholinergic pathways. Atropine and hexamethonium reduced but ACh stimulated motor activity and the effect of ACh was not changed by TTX, suggesting that the cholinergic pathway may exert a direct stimulatory effect on motor activity. Single injection of TTX, VIP(10-28) or L-NA induced a marked increase in motor activity, suggesting that the motor activity of rat proximal colon is tonically suppressed by VIP and NO generating pathways, and elimination of inhibitory neurotransmission by TTX may induce an abnormal increase of the motor activity. The interaction between VIP and NO in regulation of motor activity was further examined by a measurement of NO release from vascularly perfused rat proximal colon. Results showed that NO release was significantly increased during infusion of VIP and this response was reversed by L-NA. These results suggest that VIP generating neurons may inhibit colonic motility by stimulating endogenous NO production in either smooth muscle cells or nerve terminals.

  2. Proximity assays for sensitive quantification of proteins.

    PubMed

    Greenwood, Christina; Ruff, David; Kirvell, Sara; Johnson, Gemma; Dhillon, Harvinder S; Bustin, Stephen A

    2015-06-01

    Proximity assays are immunohistochemical tools that utilise two or more DNA-tagged aptamers or antibodies binding in close proximity to the same protein or protein complex. Amplification by PCR or isothermal methods and hybridisation of a labelled probe to its DNA target generates a signal that enables sensitive and robust detection of proteins, protein modifications or protein-protein interactions. Assays can be carried out in homogeneous or solid phase formats and in situ assays can visualise single protein molecules or complexes with high spatial accuracy. These properties highlight the potential of proximity assays in research, diagnostic, pharmacological and many other applications that require sensitive, specific and accurate assessments of protein expression. PMID:27077033

  3. Proximity assays for sensitive quantification of proteins

    PubMed Central

    Greenwood, Christina; Ruff, David; Kirvell, Sara; Johnson, Gemma; Dhillon, Harvinder S.; Bustin, Stephen A.

    2015-01-01

    Proximity assays are immunohistochemical tools that utilise two or more DNA-tagged aptamers or antibodies binding in close proximity to the same protein or protein complex. Amplification by PCR or isothermal methods and hybridisation of a labelled probe to its DNA target generates a signal that enables sensitive and robust detection of proteins, protein modifications or protein–protein interactions. Assays can be carried out in homogeneous or solid phase formats and in situ assays can visualise single protein molecules or complexes with high spatial accuracy. These properties highlight the potential of proximity assays in research, diagnostic, pharmacological and many other applications that require sensitive, specific and accurate assessments of protein expression. PMID:27077033

  4. Existence and convergence of best proximity points

    NASA Astrophysics Data System (ADS)

    Eldred, A. Anthony; Veeramani, P.

    2006-11-01

    Consider a self map T defined on the union of two subsets A and B of a metric space and satisfying T(A)[subset of or equal to]B and T(B)[subset of or equal to]A. We give some contraction type existence results for a best proximity point, that is, a point x such that d(x,Tx)=dist(A,B). We also give an algorithm to find a best proximity point for the map T in the setting of a uniformly convex Banach space.

  5. [Ultrastructural localization of adenosine triphosphatase activity in the proximal kidney tubules of white rats].

    PubMed

    Panasiuk, E N; Birov, V V; Nazar, P S; Saĭ, V G; Kavalishin, V I

    1977-10-01

    In white rats, the ferment topography of Mg+2 and (Na+ + K+)-activated ATPh-ses in proximal canaliculi was studied with the aid of the ultrastructural cytochemistry. The final product of the fermentative reaction (PhHPO4) in the form of small dense granuli is positioned on the duplicate folds of epithelial cells, the cells limiting the brush border micropiles, and on invaginations of the apical plasmalemme at the micropiles base. For (Na+ %K+)-activated ATPh-ses a localisation of the reaction product was determined in the canaliculi vessels.

  6. Kinetic transport model for cellular regulation of pH and solute concentration in the renal proximal tubule.

    PubMed Central

    Verkman, A S; Alpern, R J

    1987-01-01

    An open circuit kinetic model was developed to calculate the time course of proximal tubule cell pH, solute concentrations, and volume in response to induced perturbations in luminal or peritubular fluid composition. Solute fluxes were calculated from electrokinetic equations containing terms for known carrier saturabilities, allosteric dependences, and ion coupling ratios. Apical and basolateral membrane potentials were determined iteratively from the requirements of cell electroneutrality and equal opposing transcellular and paracellular currents. The model converged to membrane potentials accurate to 0.05% in one to four iterations. Model variables included cell concentrations of Na, K, HCO3, glucose, pH (uniform CO2), volume, and apical and basolateral membrane potentials. The basic model contained passive apical membrane transport of Na/H, Na/glucose, H and K, basolateral transport of Na/3HCO3, K, H, and glucose, and paracellular transport of Na, K, Cl, and HCO3; apical H and basolateral 3Na/2K-ATPases were present. Apical Na/H and basolateral K transport were regulated allosterically by pH. Apical Na/H transport, basolateral Na/3HCO3 transport, and the 3Na/2K-ATPase were saturable. Model parameters were chosen from data in the rat proximal tubule. Model predictions for the magnitude and time course of cell pH, Na, and membrane potential in response to rapid changes in apical and peritubular Na and HCO3 were in excellent agreement with experiment. In addition, the model requires that there exist an apical H-ATPase, basolateral Na/3HCO3 transport saturable with HCO3, and electroneutral basolateral K transport. PMID:3580482

  7. 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…

  8. Current status of proximal gastric vagotomy.

    PubMed Central

    Schirmer, B D

    1989-01-01

    Proximal gastric vagotomy is nearing its twentieth year in clinical use as an operation for peptic ulcer disease. No other acid-reducing operation has undergone as much scrutiny or study. At this time, the evidence of such studies and long-term follow-up strongly supports the use of proximal gastric vagotomy as the treatment of choice for chronic duodenal ulcer in patients who have failed medical therapy. Its application in treating the complications of peptic ulcer disease, which recently have come to represent an increasingly greater percentage of all operations done for peptic ulcer disease, is well-tested. However, initial series suggest that it should probably occupy a prominent role in treating some of these complications, particularly in selected patients, in the future. The operation has the well-documented ability to reduce gastric acid production, not inhibit gastric bicarbonate production, and also minimally inhibit gastric motility. The combination of these physiologic results after proximal gastric vagotomy, along with preservation of the normal antropyloroduodenal mechanism of gastrointestinal control, serve to allow patients with proximal gastric vagotomy the improved benefits of significantly fewer severe gastrointestinal side effects than are seen after other operations for peptic ulcer disease. PMID:2644897

  9. [Novel treatment possibilities for proximal caries].

    PubMed

    Meyer-Lueckel, Hendrik; Fejerskov, Ole; Paris, Sebastian

    2009-01-01

    So far approaches for caries treatment follow a dichotomized scheme: Non invasive options of primary and secondary prevention are contrasted to invasive treatment of caries lesions. Depending on the treatment philosophy of dentists and dental schools an early or late invasive treatment threshold is recommended. Sealing of proximal lesions as done in pit and fissures has only been established in some dental schools, so far. Moreover, infiltration of the enamel part of lesions could close the gap between preventive and invasive measures. Most of these novel treatment options for proximal surfaces are currently in the last stages of product development. With respect to the good clinical results of proximal sealing with conventional sealants, this regimen seems already be recommendable to hamper further lesion progression in clinical practice. Caries infiltration of lesions situated on proximal and other smooth surfaces might even be a more promising approach, if clinical studies corroborate the recent in vitro findings. All these novel limited invasive strategies might be suitable to complete the current dichotomized way of caries treatment.

  10. Laparoscopic Proximal Gastrectomy With Gastric Tube Reconstruction

    PubMed Central

    Shiraishi, Norio; Toujigamori, Manabu; Shiroshita, Hidefumi; Etoh, Tsuyoshi; Inomata, Masafumi

    2016-01-01

    Background and Objectives: There is no standardized method of reconstruction in laparoscopic proximal gastrectomy (LPG). We present a novel technique of reconstruction with a long, narrow gastric tube in LPG for early gastric cancer (EGC). Methods: During the laparoscopic procedure, the upper part of the stomach is fully mobilized with perigastric and suprapancreatic lymphadenectomy, and then the abdominal esophagus is transected. After a minilaparotomy is created, the entire stomach is pulled outside. A long, narrow gastric tube (20 cm long, 3 cm wide) is created with a linear stapler. The proximal part of the gastric tube is formed into a cobra head shape for esophagogastric tube anastomosis, which is then performed with a 45-mm linear stapler under laparoscopic view. The end of the esophagus is fixed on the gastric tube to prevent postoperative esophageal reflux. Results: Thirteen patients with early proximal gastric cancer underwent the procedure. The mean operative time was 283 min, and median blood loss was 63 ml. There were no conversions to open surgery, and no intraoperative complications. Conclusion: This new technique of reconstruction after LPG is simple and feasible. The procedure has the potential of becoming a standard reconstruction technique after LPG for proximal EGC. PMID:27547027

  11. Vortices in normal part of proximity system

    SciTech Connect

    Kogan, V. G.

    2015-05-26

    It is shown that the order parameter Δ induced in the normal part of superconductor-normal-superconductor proximity system is modulated in the magnetic field differently from vortices in bulk superconductors. Whereas Δ turns zero at vortex centers, the magnetic structure of these vortices differs from that of Abrikosov's.

  12. Factors affecting proximal tubular reabsorption during development

    SciTech Connect

    Kaskel, F.J.; Kumar, A.M.; Lockhart, E.A.; Evan, A.; Spitzer, A.

    1987-01-01

    Studies performed in several animal species have demonstrated that glomerulotubular balance is maintained throughout development despite the many changes that occur in the factors known to control it. In an attempt to understand the nature of this phenomenon the authors quantified the magnitude and described the profile of these changes in guinea pigs. The changes in physical forces were assessed from measurements of hydrostatic and oncotic pressures, whereas those in the permeability characteristics of the proximal tubule epithelium were estimated from permanence to radioactivity-labelled macromolecules of graded radii, histologic measurements of the intercellular channels, and measurements of end-proximal ratio of tubular fluid-to-plasma osmolality (TF/P/sub osm/). Between 1 and 50 days of age the net pressure for reabsorption increased from 15.0 to 30.9 mmHg with the major change occurring during the first 2-3 wk of postnatal life. The urinary recovery of (/sup 3/H)inulin, (/sup 14/C)sucrose, and (/sup 14/C)creatinine, injected in the early segment of proximal tubules did not vary with age. The urinary recovery of (/sup 14/C)mannitol increased from 92% at birth to 100% at 49 days of age. The length of the zonulae occludens and the width of the intercellular channels did not change during this period. The findings support the hypothesis that during early postnatal life glomerulotubular balance is made possible by a high permeability of the proximal tubule, which compensates for the low net reabsorptive pressure. As the animal matures and the proximal tubule epithelium becomes tighter, for glomerulotubular balance to be maintained, an increase in the number of intercellular channels and in the active transport of sodium need to be postulated.

  13. Compensatory regulation of Na+ absorption by Na+/H+ exchanger and Na+-Cl- cotransporter in zebrafish (Danio rerio)

    PubMed Central

    2013-01-01

    Introduction In mammals, internal Na+ homeostasis is maintained through Na+ reabsorption via a variety of Na+ transport proteins with mutually compensating functions, which are expressed in different segments of the nephrons. In zebrafish, Na+ homeostasis is achieved mainly through the skin/gill ionocytes, namely Na+/H+ exchanger (NHE3b)-expressing H+-ATPase rich (HR) cells and Na+-Cl- cotransporter (NCC)-expressing NCC cells, which are functionally homologous to mammalian proximal and distal convoluted tubular cells, respectively. The present study aimed to investigate whether or not the functions of HR and NCC ionocytes are differentially regulated to compensate for disruptions of internal Na+ homeostasis and if the cell differentiation of the ionocytes is involved in this regulation pathway. Results Translational knockdown of ncc caused an increase in HR cell number and a resulting augmentation of Na+ uptake in zebrafish larvae, while NHE3b loss-of-function caused an increase in NCC cell number with a concomitant recovery of Na+ absorption. Environmental acid stress suppressed nhe3b expression in HR cells and decreased Na+ content, which was followed by up-regulation of NCC cells accompanied by recovery of Na+ content. Moreover, knockdown of ncc resulted in a significant decrease of Na+ content in acid-acclimated zebrafish. Conclusions These results provide evidence that HR and NCC cells exhibit functional redundancy in Na+ absorption, similar to the regulatory mechanisms in mammalian kidney, and suggest this functional redundancy is a critical strategy used by zebrafish to survive in a harsh environment that disturbs body fluid Na+ homeostasis. PMID:23924428

  14. Juvenile xanthogranuloma of the proximal nail fold.

    PubMed

    Piraccini, Bianca Maria; Fanti, Pier Alessandro; Iorizzo, Matilde; Tosti, Antonella

    2003-01-01

    An 18-month-old Caucasian boy presented with a firm 0.5 mm nodule, pink-red in color, with a yellow hue and some telangiectases on the surface, localized on the right thumbnail. The nodule involved all of the proximal nail fold and covered the proximal third of the nail. Pathology showed a dense dermal infiltrate of histiocytes, some of which had foamy nuclei, and multinucleated Touton giant cells. The lesion progressively decreased in size and had completely disappeared after 3 years. Periodic follow-up was important not only to monitor evolution of the juvenile xanthogranuloma, but also to avoid excessive growth of the lesion with possible definitive nail matrix damage.

  15. Painful Spastic Hip Dislocation: Proximal Femoral Resection

    PubMed Central

    Albiñana, Javier; Gonzalez-Moran, Gaspar

    2002-01-01

    The dislocated hip in a non-ambulatory child with spastic paresis tends to be a painful interference to sleep, sitting upright, and perineal care. Proximal femoral resection-interposition arthroplasty is one method of treatment for this condition. We reviewed eight hips, two bilateral cases, with a mean follow-up of 30 months. Clinical improvement was observed in all except one case, with respect to pain relief and sitting tolerance. Some proximal migration was observed in three cases, despite routine post-operative skeletal traction in all cases and careful soft tissue interposition. One case showed significant heterotopic ossification which restricted prolonged sitting. This patient needed some occasional medication for pain. PMID:12180614

  16. Children's memory and proximity to violence.

    PubMed

    Pynoos, R S; Nader, K

    1989-03-01

    The study examined 133 school-age children's memory of a sniper attack at their elementary school. Researchers analyzed the role that spatial representation, memory markers, inner plans of action, and strategies of recall played in the memory process. In recalling the event, exposed children reduced their degree of life threat, while nonexposed children increased their proximity to the violence. Clinical and forensic implications are discussed.

  17. Endoscopic proximal hamstring repair and ischial bursectomy.

    PubMed

    Dierckman, Brian D; Guanche, Carlos A

    2012-12-01

    With the significant increase in use of the arthroscope around the hip have come several less invasive techniques to manage pathologies around this joint. This technical note with a video details one such technique that allows for the endoscopic management of proximal hamstring tears and chronic ischial bursitis, which until now have been managed exclusively with much larger open approaches. This procedure allows for complete exposure of the posterior aspect of the hip in a safe, minimally invasive fashion. PMID:23766996

  18. Proximal Sciatic Nerve Intraneural Ganglion Cyst

    PubMed Central

    Swartz, Karin R.; Wilson, Dianne; Boland, Michael; Fee, Dominic B.

    2009-01-01

    Intraneural ganglion cysts are nonneoplastic, mucinous cysts within the epineurium of peripheral nerves which usually involve the peroneal nerve at the knee. A 37-year-old female presented with progressive left buttock and posterior thigh pain. Magnetic resonance imaging revealed a sciatic nerve mass at the sacral notch which was subsequently revealed to be an intraneural ganglion cyst. An intraneural ganglion cyst confined to the proximal sciatic nerve has only been reported once prior to 2009. PMID:20069041

  19. Proximal tibial fracture following total knee arthroplasty.

    PubMed

    Krause, Heike; Dunleavy, Kim

    2011-09-01

    The patient was a 74-year-old man, with a history of total knee arthoplasty 14 years earlier, after having sustained a pathological fracture of the proximal diaphysis of the left tibia following a fall. Given the unstable nature of the fracture and the severe osteolysis noted below the total knee arthroplasty, surgical management 1 day after the fall entailed packing cancellous bone graft into the defect and realigning the fracture. PMID:21885911

  20. Transverse Stress Fracture of the Proximal Patella

    PubMed Central

    Atsumi, Satoru; Arai, Yuji; Kato, Ko; Nishimura, Akinobu; Nakazora, Shigeto; Nakagawa, Shuji; Ikoma, Kazuya; Fujiwara, Hiroyoshi; Sudo, Akihiro; Kubo, Toshikazu

    2016-01-01

    Abstract Among stress fractures associated with sports activities, patellar stress fracture is rare. Regarding patella stress fractures, so far only distal transverse or lateral longitudinal fractures have been reported, but there are no reports of transverse fractures occurring in the proximal patella. We describe an extremely rare case of transverse stress fracture of proximal patella in a 9-year-old athlete. A 9-year old boy, who participated in sports (sprints and Kendo) presented with left knee pain without any external injury. In plain radiographs, a fracture line was observed in the proximal 1/3 of the left patella, and a patella stress fracture was diagnosed. For treatment, because 7 months of conservative therapy showed no improvement, internal fixation was carried out using Acutrak screws, and bone union was thus achieved. Three months after the operation, he was able to return to his previous level of athletic sports activity. Regarding the mechanism of onset, it is believed that the causes are longitudinal traction force and patellofemoral contact pressure. On the other hand, the contact region of the patella with the femur changes with the flexion angle of the knee. In the current case, the fracture occurred at a site where the patella was in contact with the femur at a flexion angle of >90°, so it is believed that it occurred as a clinical condition from being subjected to repeated longitudinal traction force and patellofemoral contact pressure at a flexion angle of >90°, during the sports activities of sprints and Kendo. The nonunion of the transverse stress fracture of his proximal patella was successfully treated with internal fixation using Acutrak screws. PMID:26871789

  1. Large proximal ureteral stones: Ideal treatment modality?

    PubMed Central

    Kadyan, B.; Sabale, V.; Mane, D.; Satav, V.; Mulay, A.; Thakur, N.; Kankalia, S. P.

    2016-01-01

    Background and Purpose: Ideal treatment modality for patients with large impacted proximal ureteral stone remains controversial. We compared laparoscopic transperitoneal ureterolithotomy (Lap-TPUL) and semirigid ureteroscopy for large proximal ureteric stones to evaluate their efficacy and safety. Patients and Methods: From November 2012 to December 2014, we enrolled 122 patients with large (≥1.5 cm) proximal ureteral stone in the study. Patients were randomly divided into two groups: Group A (60 patients), retrograde ureteroscopic lithotripsy using a semirigid ureteroscope; Group B (62 patients), transperitoneal LU (Lap-TPUL). Results: The overall stone-free rate was 71.6% and 93.5% for Group A and Group B respectively (P = 0.008). Auxiliary procedure rate was higher in Group A than in Group B (27.3% vs. 5.6%). The complication rate was 11.2% in Group B versus 25% in Group A. Mean procedure time was higher in laparoscopy group as compared to ureterorenoscopy (URS) groups (84.07 ± 16.80 vs. 62.82 ± 12.71 min). Hospital stay was 4.16 ± 0.67 days in laparoscopy group and 1.18 ± 0.38 days in URS group (P < 0.0001). Conclusion: Laparoscopic transperitoneal ureterolithotomy is a minimally invasive, safe and effective treatment modality and should be recommended to all patients of impacted large proximal stones, which are not amenable to URS or extracorporeal shock-wave lithotripsy or as a primary modality of choice especially if patient is otherwise candidate for open surgery. PMID:27141190

  2. Bilateral Brodie's abscess at the proximal tibia.

    PubMed

    Buldu, Halil; Bilen, Fikri Erkal; Eralp, Levent; Kocaoglu, Mehmet

    2012-08-01

    Brodie's abscess is a form of subacute osteomyelitis, which typically involves the metaphyses of the long tubular bones, particularly in the tibia. The diagnosis is usually made incidentally, as there are no accompanying symptoms or laboratory studies. Bilateral involvement at the proximal tibia is unusual. However, orthopaedic surgeons should be aware of this entity, as it may present without symptoms. Checking the contralateral limb for concomitant Brodie's abscess is recommended.

  3. Human proximal tubule cells form functional microtissues.

    PubMed

    Prange, Jenny A; Bieri, Manuela; Segerer, Stephan; Burger, Charlotte; Kaech, Andres; Moritz, Wolfgang; Devuyst, Olivier

    2016-04-01

    The epithelial cells lining the proximal tubules of the kidney mediate complex transport processes and are particularly vulnerable to drug toxicity. Drug toxicity studies are classically based on two-dimensional cultures of immortalized proximal tubular cells. Such immortalized cells are dedifferentiated, and lose transport properties (including saturable endocytic uptake) encountered in vivo. Generating differentiated, organotypic human microtissues would potentially alleviate these limitations and facilitate drug toxicity studies. Here, we describe the generation and characterization of kidney microtissues from immortalized (HK-2) and primary (HRPTEpiC) human renal proximal tubular epithelial cells under well-defined conditions. Microtissue cultures were done in hanging drop GravityPLUS™ culture plates and were characterized for morphology, proliferation and differentiation markers, and by monitoring the endocytic uptake of albumin. Kidney microtissues were successfully obtained by co-culturing HK-2 or HRPTEpiC cells with fibroblasts. The HK-2 microtissues formed highly proliferative, but dedifferentiated microtissues within 10 days of culture, while co-culture with fibroblasts yielded spherical structures already after 2 days. Low passage HRPTEpiC microtissues (mono- and co-culture) were less proliferative and expressed tissue-specific differentiation markers. Electron microscopy evidenced epithelial differentiation markers including microvilli, tight junctions, endosomes, and lysosomes in the co-cultured HRPTEpiC microtissues. The co-cultured HRPTEpiC microtissues showed specific uptake of albumin that could be inhibited by cadmium and gentamycin. In conclusion, we established a reliable hanging drop protocol to obtain functional kidney microtissues with proximal tubular epithelial cell lines. These microtissues could be used for high-throughput drug and toxicology screenings, with endocytosis as a functional readout. PMID:26676951

  4. Bilateral, atraumatic, proximal tibiofibular joint instability.

    PubMed

    Morrison, Troy D; Shaer, James A; Little, Jill E

    2011-01-01

    Dislocation of the tibiofibular joint is rare and usually results from a traumatic event. Only 1 case of atraumatic proximal tibiofibular joint instability in a 14-year-old girl has been reported in the literature, however this condition might occur more frequently than once thought. A wide range of treatment options exist for tibiofibular dislocations. Currently, the first choice is a conservative approach, and when this fails, surgical means such as resection of the fibula head, arthrodesis, and reconstruction are considered. However, no consensus exists on the most effective treatment. This article reports a unique case of bilateral, atraumatic, proximal tibia and fibular joint instability involving a 30-year-old man with a 20-year history of pain and laxity in the right knee. The patient had no trauma to his knees; he reported 2 immediate family members with similar complaints, which suggests that this case is likely congenital. After conservative approaches proved to be ineffective, the patient underwent capsular reconstruction using free autologous gracilis tendon. At 6-month postoperative follow-up, the patient was pain free with no locking and instability. He then underwent surgery on the left knee. At 1-year follow-up after the second surgery, the patient had no symptoms or restrictions in mobility. We provide an alternative surgical approach to arthrodesis and resection for the treatment of chronic proximal tibiofibular instability. In the treatment of chronic tibiofibular instability, we believe that reconstruction of the tibiofibular joint is a safe and effective choice.

  5. 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

  6. 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.

  7. Management of proximal humerus fractures in adults.

    PubMed

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

    2014-11-18

    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.

  8. Proximal myopathy: diagnostic approach and initial management.

    PubMed

    Suresh, Ernest; Wimalaratna, Sunil

    2013-08-01

    Proximal myopathy presents as symmetrical weakness of proximal upper and/or lower limbs. There is a broad range of underlying causes including drugs, alcohol, thyroid disease, osteomalacia, idiopathic inflammatory myopathies (IIM), hereditary myopathies, malignancy, infections and sarcoidosis. Clinical assessment should aim to distinguish proximal myopathy from other conditions that can present similarly, identify patients who need prompt attention, like those with cardiac, respiratory or pharyngeal muscle involvement, and determine underlying cause of myopathy. Initial evaluation should include simple tests, like creatine kinase, thyroid function and (25)OH vitamin D levels, but further evaluation including neurophysiological studies, muscle imaging and muscle biopsy should be considered for patients in whom no toxic, metabolic or endocrine cause is found, and in those with clinical features suggestive of inflammatory or hereditary myopathy. Additionally, screening for malignancy and testing for anti-Jo1 antibody is indicated for selected patients with IIM. Management depends on underlying cause, and includes measures, such as removal of offending agent, correction of endocrine or metabolic problem, corticosteroids and immunosuppressive therapy for IIM, and physical therapy, rehabilitation and genetic counselling for muscular dystrophies.

  9. Salicylate-induced proximal tubular dysfunction.

    PubMed

    Tsimihodimos, Vasilis; Psychogios, Nikolaos; Kakaidi, Varvara; Bairaktari, Eleni; Elisaf, Moses

    2007-09-01

    We describe the case of a 17-year-old girl who was admitted to our clinic for drug poisoning. Twelve hours after the ingestion of 25 tablets of aspirin (12.5 g of acetylsalicylic acid), the patient had a generalized proximal tubular dysfunction characterized by glucosuria (in the face of normal serum glucose levels), proteinuria, and uric acid wasting. Further characterization of the tubular dysfunction using high-resolution proton nuclear magnetic resonance spectroscopy of the urine showed a pattern consistent with proximal tubular injury. An important characteristic of the salicylate-induced proximal tubular dysfunction in our patient was its rapid reversibility. A trend toward normalization of fractional excretion values of electrolytes was observed 2 days after ingestion. Determination of serum and urine metabolites and spectroscopy of urine 15 days later showed no evidence of tubular dysfunction. The mechanisms potentially implicated in the pathogenesis of salicylate-induced Fanconi syndrome are discussed and a brief review of the relevant literature is provided. PMID:17720526

  10. 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.

  11. Gene teams with relaxed proximity constraint.

    PubMed

    Kim, Sun; Choi, Jeong-Hyeon; Yang, Jiong

    2005-01-01

    Functionally related genes co-evolve, probably due to the strong selection pressure in evolution. Thus we expect that they are present in multiple genomes. Physical proximity among genes, known as gene team, is a very useful concept to discover functionally related genes in multiple genomes. However, there are also many gene sets that do not preserve physical proximity. In this paper, we generalized the gene team model, that looks for gene clusters in a physically clustered form, to multiple genome cases with relaxed constraint. We propose a novel hybrid pattern model that combines the set and the sequential pattern models. Our model searches for gene clusters with and/or without physical proximity constraint. This model is implemented and tested with 97 genomes (120 replicons). The result was analyzed to show the usefulness of our model. Especially, analysis of gene clusters that belong to B. subtilis and E. coli demonstrated that our model predicted many experimentally verified operons and functionally related clusters. Our program is fast enough to provide a sevice on the web at http://platcom. informatics.indiana.edu/platcom/. Users can select any combination of 97 genomes to predict gene teams.

  12. Optical system for proximity operations in aerospace

    NASA Astrophysics Data System (ADS)

    Zhang, Yong-Liang; Liu, Xiao-Chun; Lu, Huan-Zhang

    2008-12-01

    Satellite serving offers a potential for extending the life of satellites and reducing launching and operating costs. Proximity operations are necessary for purpose of satellite serving. As the primary measurement system, optical system can provide the information of relative navigation in near field. The paper has two main contributions. Firstly, we summarize use of optical systems for guidance and navigation in the missions of proximity operations in aerospace. Their characteristics vary from the manned missions, which are performed by astronauts on-orbit, through semi-autonomous missions, wherein human operators on the ground segment issue high level directives and sensor-guided systems on the space segment guide the execution, to the full-autonomous missions, which are executed using unmanned space robotic systems. It comes to light that future space operations will be more autonomous. Secondly, we present a concept and framework of a vision system for satellite proximity operations, which is semi-autonomous and can treat with uncooperative satellites. The vision system uses visible and infrared sensors synchronously to acquire images, which solves the problem of data integrity introduced by ambient illumination and direct sunlight for visible sensor. The vision system uses natural features on the satellite surfaces instead of artificial markers for its operation, computes relative motion and structure of the target, and tracks features in image sequences. Selected algorithms of the system have been characterized in ground environment; they are undergoing systematic sets of adaptation for space.

  13. Analytical parametrization of fusion barriers using proximity potentials

    NASA Astrophysics Data System (ADS)

    Dutt, Ishwar; Puri, Rajeev K.

    2010-06-01

    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.

  14. Mechanisms of adaptation to chronic respiratory acidosis in the rabbit proximal tubule.

    PubMed Central

    Krapf, R

    1989-01-01

    The hyperbicarbonatemia of chronic respiratory acidosis is maintained by enhanced bicarbonate reabsorption in the proximal tubule. To investigate the cellular mechanisms involved in this adaptation, cell and luminal pH were measured microfluorometrically using (2",7')-bis(carboxyethyl)-(5,6)-carboxyfluorescein in isolated, microperfused S2 proximal convoluted tubules from control and acidotic rabbits. Chronic respiratory acidosis was induced by exposure to 10% CO2 for 52-56 h. Tubules from acidotic rabbits had a significantly lower luminal pH after 1-mm perfused length (7.03 +/- 0.09 vs. 7.26 +/- 0.06 in controls, perfusion rate = 10 nl/min). Chronic respiratory acidosis increased the initial rate of cell acidification (dpHi/dt) in response to luminal sodium removal by 63% and in response to lowering luminal pH (7.4-6.8) by 69%. Chronic respiratory acidosis also increased dpHi/dt in response to peritubular sodium removal by 63% and in response to lowering peritubular pH by 73%. In conclusion, chronic respiratory acidosis induces a parallel increase in the rates of the luminal Na/H antiporter and the basolateral Na/(HCO3)3 cotransporter. Therefore, the enhanced proximal tubule reabsorption of bicarbonate in chronic respiratory acidosis may be, at least in part, mediated by a parallel adaptation of these transporters. PMID:2537851

  15. Proximal tubule NHE3 activity is inhibited by beta-arrestin-biased angiotensin II type 1 receptor signaling.

    PubMed

    Carneiro de Morais, Carla P; Polidoro, Juliano Z; Ralph, Donna L; Pessoa, Thaissa D; Oliveira-Souza, Maria; Barauna, Valério G; Rebouças, Nancy A; Malnic, Gerhard; McDonough, Alicia A; Girardi, Adriana C C

    2015-10-15

    Physiological concentrations of angiotensin II (ANG II) upregulate the activity of Na(+)/H(+) exchanger isoform 3 (NHE3) in the renal proximal tubule through activation of the ANG II type I (AT1) receptor/G protein-coupled signaling. This effect is key for maintenance of extracellular fluid volume homeostasis and blood pressure. Recent findings have shown that selective activation of the beta-arrestin-biased AT1 receptor signaling pathway induces diuresis and natriuresis independent of G protein-mediated signaling. This study tested the hypothesis that activation of this AT1 receptor/beta-arrestin signaling inhibits NHE3 activity in proximal tubule. To this end, we determined the effects of the compound TRV120023, which binds to the AT1R, blocks G-protein coupling, and stimulates beta-arrestin signaling on NHE3 function in vivo and in vitro. NHE3 activity was measured in both native proximal tubules, by stationary microperfusion, and in opossum proximal tubule (OKP) cells, by Na(+)-dependent intracellular pH recovery. We found that 10(-7) M TRV120023 remarkably inhibited proximal tubule NHE3 activity both in vivo and in vitro. Additionally, stimulation of NHE3 by ANG II was completely suppressed by TRV120023 both in vivo as well as in vitro. Inhibition of NHE3 activity by TRV120023 was associated with a decrease in NHE3 surface expression in OKP cells and with a redistribution from the body to the base of the microvilli in the rat proximal tubule. These findings indicate that biased signaling of the beta-arrestin pathway through the AT1 receptor inhibits NHE3 activity in the proximal tubule at least in part due to changes in NHE3 subcellular localization. PMID:26246427

  16. 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…

  17. Scintillation proximity assay using polymeric membranes

    SciTech Connect

    Mansfield, R.K.

    1992-01-01

    Liquid scintillation counting (LSC) is typically used to quantify electron emitting isotopes. In LSC, radioactive samples are dissolved in an organic fluor solution (scintillation cocktail) to ensure that the label is close enough to the fluor molecules to be detected. Although efficient, scintillation cocktail is neither specific or selective for samples labeled with the same radioisotope. Scintillation cocktail is flammable posing significant health risks to the user and is expensive to purchase and discard. Scintillation Proximity Assay (SPA) is a radioanalytical technique where only those radiochemical entities (RCE's) bound to fluor containing matrices are detected. Only bound RCE's are in close enough proximity the entrapped fluor molecules to induce scintillations. Unbound radioligands are too far removed from the fluor molecules to be detected. The research in this dissertation focused on the development and evaluation of fluor-containing membranes (scintillation proximity membranes, SP membranes) to be used for specific radioanalytical techniques without using scintillation cocktail. Polysulfone and PVC SP membranes prepared in our laboratory were investigated for radioimmunossay (RIA) where only bound radioligand is detected, thereby eliminating the separation step impeding the automation of RIA. These SP membranes performed RIA where the results were nearly identical to commercial SP microbeads. SP membranes functionalized with quaternary ammonium hydroxide moieties were able to trap and quantify [sup 14]CO[sub 2] without using liquid scintillation cocktail. RCE's bound in the pore structure of SP membranes are intimate with the entrapped fluor providing the geometry needed for high detection efficiencies. Absorbent SP membranes were used in radiation surveys and were shown to be as effective as conventional survey techniques using filter paper and scintillation cocktail.

  18. Delayed homicides and the proximate cause.

    PubMed

    Lin, Peter; Gill, James R

    2009-12-01

    Delayed homicides result from complications of remote injuries inflicted by "the hands of another." The investigation of delayed homicides may be a challenge due to a number of factors including: failure to report the death to the proper authorities, lack of ready and adequate documentation of the original injury and circumstances, and jurisdictional differences between the places of injury and death. The certification of these deaths also requires the demonstration of a pathophysiologic link between the remote injury and death. In sorting through these issues, it is helpful to rely upon the definition of the proximate cause of death. Over a 2-year period in New York City, there were 1211 deaths certified as homicide of which 42 were due to injuries sustained greater than 1 year before death. The survival interval ranged from 1.3 to 43.2 years. The most common immediate causes of death were: infections (22), seizures (7), and intestinal obstructions/hernias (6). Common patterns of complications included infection following a gunshot wound of the spinal cord, seizure disorder due to blunt head trauma, and intestinal obstruction/hernia due to adhesions from an abdominal stab wound. Spinal cord injuries resulted in paraplegia in 14 instances and quadriplegia in 8. The mean survival interval for paraplegics was 20.3 years and 14.8 years for quadriplegics; infections were a frequent immediate cause of death in both groups, particularly infections due to chronic bladder catheterization. The definition of proximate cause originated with civil law cases and was later applied to death certification as the proximate cause of death. The gradual extinction of the "year and a day rule" for the limitation of bringing homicide charges in delayed deaths may result in more of these deaths going to trial. Medical examiners/coroners must be able to explain the reasoning behind these death certifications and maintain consistent standards for the certification of all delayed deaths due

  19. Hand Replantation with Proximal Row Carpectomy

    PubMed Central

    Lee, Young-Keun; Lee, Hang-Ho; Park, Ji-Kang; Kim, Joo-Yong; Dhawan, Vikas

    2008-01-01

    The purpose of this study is to present our operative technique and postoperative results of the hand replantation with proximal row carpectomy in cases of complete amputation at the level of wrist joint. From May 2003 to April 2005, five patients suffered from complete amputation of the hand due to industrial trauma. Amputation level was radiocarpal joint in three cases and midcarpal joint in two cases. Three cases represented guillotine type and two cases with local crush type injuries. All were men and the mean age was 26.6 years. The mean follow-up period was 26.8 months. At the time of replantation, the wrist joint was stabilized with transarticular fixation using three to four Kirschner’s wires after performing proximal row carpectomy. Postoperatively, functional results such as muscle strength, range of motion of the wrist and fingers, and sensory recovery were assessed according to Chen’s criteria. Joint width and arthritic changes of the radio-capitate joint were evaluated with radiologic tools. According to Chen’s criteria, the overall results in five cases were classified as grade II. Intrinsic muscle power of hands was found to be grade 4. The mean grip and pinch powers were 41% and 45%, respectively, compared to contralateral hand. The mean arc of flexion–extension of wrist was 53°. Total mean active motion of fingers was 215 degrees. Static two-point discrimination of fingertip ranged from 8 to 13 mm. On the follow-up, computerized tomography showed well-preserved radio-capitate joint space without any arthritic changes. While performing hand replantation after amputation at the radiocarpal or midcarpal level, proximal row carpectomy is a useful procedure to preserve joint motion of the wrist in selected cases. PMID:18855073

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

    PubMed

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

    2002-04-01

    Rabbit kidney proximal convoluted tubule (RPCT) and proximal straight tubule (RPST) cells were independently isolated and cultured. The kinetics of the sodium-dependent glucose transport was characterized by determining the uptake of the glucose analog alpha-methylglucopyranoside. Cell culture and assay conditions used in these experiments were based on previous experiments conducted on the renal cell line derived from the whole kidney of the Yorkshire pig (LLC-PK1). Results indicated the presence of two distinct sodium-dependent glucose transporters in rabbit renal cells: a relatively high-capacity, low-affinity transporter (V(max) = 2.28 +/- 0.099 nmoles/mg protein min, Km = 4.1 +/- 0.27 mM) in RPCT cells and a low-capacity, high-affinity transporter (V(max) = 0.45 +/- 0.076 nmoles/mg protein min, K(m) = 1.7 +/- 0.43 mM) in RPST cells. A relatively high-capacity, low-affinity transporter (V(max) = 1.68 +/- 0.215 nmoles/mg protein min, Km = 4.9 +/- 0.23 mM) was characterized in LLC-PK1 cells. Phlorizin inhibited the uptake of alpha-methylglucopyranoside in proximal convoluted, proximal straight, and LLC-PK1 cells by 90, 50, and 90%, respectively. Sodium-dependent glucose transport in all three cell types was specific for hexoses. These data are consistent with the kinetic heterogeneity of sodium-dependent glucose transport in the S1-S2 and S3 segments of the mammalian renal proximal tubule. The RPCT-RPST cultured cell model is novel, and this is the first report of sodium-dependent glucose transport characterization in primary cultures of proximal straight tubule cells. Our results support the use of cultured monolayers of RPCT and RPST cells as a model system to evaluate segment-specific differences in these renal cell types.

  1. Impacted valgus fractures of the proximal humerus.

    PubMed

    Ribeiro, Fabiano Rebouças; Takesian, Fernando Hovaguim; Bezerra, Luiz Eduardo Pimentel; Filho, Rômulo Brasil; Júnior, Antonio Carlos Tenor; da Costa, Miguel Pereira

    2016-01-01

    Impacted valgus fractures of the proximal humerus are considered to be a special type fracture, since impaction of the humeral head on the metaphysis with maintenance of the posteromedial periosteum improves the prognosis regarding occurrences of avascular necrosis. This characteristic can also facilitate the reduction maneuver and increase the consolidation rate of these fractures, even in more complex cases. The studies included were obtained by searching the Bireme, Medline, PubMed, Cochrane Library and Google Scholar databases for those published between 1991 and 2013. The objective of this study was to identify the most common definitions, classifications and treatment methods used for these fractures in the orthopedic medical literature.

  2. Ewing's sarcoma of proximal humeral epiphysis.

    PubMed

    Esmaili, Heydar Ali; Niknejad, Mohammad Taghi; Mohajeri, Shiva

    2015-02-01

    Ewing's sarcoma is one of the most common primary bone tumors of childhood. The tumor is almost always metaphyseal or diaphyseal, within long bones. In children, lesions of the epiphysis are often benign, with the most common diagnosis being chondroblastoma. Rarely, 1%-2% of Ewing sarcomas may involve epiphysis. We present a case of Ewing's sarcoma of the proximal humeral epiphysis in a 13-year-old boy. This case adds to previously reported cases of epiphyseal Ewing sarcoma and suggests that the diagnosis should be considered for pediatric epiphyseal lesions. PMID:25644805

  3. Fractures of the proximal humeral epiphysis.

    PubMed

    Burgos-Flores, J; Gonzalez-Herranz, P; Lopez-Mondejar, J A; Ocete-Guzman, J G; Amaya-Alarcón, S

    1993-01-01

    Twenty-two patients with marked displacement of a fracture of the proximal humeral epiphysis have been treated with closed or open reduction and fixation by Kirschner wires. At an average follow-up of 6.8 years there have been good functional results in almost all patients (91.1), with better results in patients under 13 years of age particularly with less residual displacement or angulation. Since there is a greater occurrence of residual deformity and symmetria and limitation of motion in older patients, a more aggressive approach to correct the initial displacement and angulation is warranted in those over the age of 13 years.

  4. Unilateral Isolated Proximal Femoral Focal Deficiency

    PubMed Central

    Doğer, Emek; Köpük, Şule Y.; Çakıroğlu, Yiğit; Çakır, Özgür; Yücesoy, Gülseren

    2013-01-01

    Objective. To discuss a patient with a prenatal diagnosis of unilateral isolated femoral focal deficiency. Case. Antenatal diagnosis of unilateral isolated femoral focal deficiency was made at 20 weeks of gestation. The length of left femur was shorter than the right, and fetal femur length was below the fifth percentile. Proximal femoral focal deficiency was diagnosed. After delivery, the diagnosis was confirmed with skeletal radiographs and magnetic resonance imaging. In prenatal ultrasonographic examination, the early recognition and exclusion of skeletal dysplasias is important; moreover, treatment plans should be initiated, and valuable information should be provided to the family. PMID:23984135

  5. Proximal monomelic amyotrophy of the upper limb.

    PubMed

    Amir, D; Magora, A; Vatine, J J

    1987-07-01

    A 30-year-old patient of Central European origin, suffering from monomelic amyotrophy, is presented. The disease was characterized by proximal weakness of one upper limb, mainly of the shoulder girdle, accompanied by atrophy. The electrodiagnostic examination revealed signs of partial denervation in the presence of normal motor and sensory conduction. The disease, which is probably of the anterior horn cells, had a benign course and good prognosis, as evident from repeated examinations during a follow-up of eight years. PMID:3606370

  6. Impacted valgus fractures of the proximal humerus☆

    PubMed Central

    Ribeiro, Fabiano Rebouças; Takesian, Fernando Hovaguim; Bezerra, Luiz Eduardo Pimentel; Filho, Rômulo Brasil; Júnior, Antonio Carlos Tenor; da Costa, Miguel Pereira

    2016-01-01

    Impacted valgus fractures of the proximal humerus are considered to be a special type fracture, since impaction of the humeral head on the metaphysis with maintenance of the posteromedial periosteum improves the prognosis regarding occurrences of avascular necrosis. This characteristic can also facilitate the reduction maneuver and increase the consolidation rate of these fractures, even in more complex cases. The studies included were obtained by searching the Bireme, Medline, PubMed, Cochrane Library and Google Scholar databases for those published between 1991 and 2013. The objective of this study was to identify the most common definitions, classifications and treatment methods used for these fractures in the orthopedic medical literature. PMID:27069878

  7. 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

  8. 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.

  9. Testing simple indices of habitat proximity.

    PubMed

    Winfree, Rachael; Dushoff, Jonathan; Crone, Elizabeth E; Schultz, Cheryl B; Budny, Robert V; Williams, Neal M; Kremen, Claire

    2005-06-01

    Simple measures of habitat proximity made primarily on the basis of land cover are widely used in the ecological literature to infer habitat connectivity, or the potential for animal movement among resource patches. However, such indices rarely have been tested against observations of animal movement or against more detailed biological models. We developed a priori expectations as to the types of study systems and organisms for which various habitat proximity indices would be best suited. We then used data from three study systems and four species to test which, if any, of the indices were good predictors of population-level responses. Our a priori expectations about index performance were not upheld. The indices that consider both habitat area and distance from the focal patch were highly correlated with each other, suggesting that they do index similar quantities. However, none of the indices performed well in predicting population response variables. The results suggest that the pattern of habitat cover alone may be insufficient to predict the process of animal movement.

  10. Fast proximity algorithm for MAP ECT reconstruction

    NASA Astrophysics Data System (ADS)

    Li, Si; Krol, Andrzej; Shen, Lixin; Xu, Yuesheng

    2012-03-01

    We arrived at the fixed-point formulation of the total variation maximum a posteriori (MAP) regularized emission computed tomography (ECT) reconstruction problem and we proposed an iterative alternating scheme to numerically calculate the fixed point. We theoretically proved that our algorithm converges to unique solutions. Because the obtained algorithm exhibits slow convergence speed, we further developed the proximity algorithm in the transformed image space, i.e. the preconditioned proximity algorithm. We used the bias-noise curve method to select optimal regularization hyperparameters for both our algorithm and expectation maximization with total variation regularization (EM-TV). We showed in the numerical experiments that our proposed algorithms, with an appropriately selected preconditioner, outperformed conventional EM-TV algorithm in many critical aspects, such as comparatively very low noise and bias for Shepp-Logan phantom. This has major ramification for nuclear medicine because clinical implementation of our preconditioned fixed-point algorithms might result in very significant radiation dose reduction in the medical applications of emission tomography.

  11. Proximal intentional neglect: a case study.

    PubMed Central

    Gold, M; Shuren, J; Heilman, K M

    1994-01-01

    Although neglect has been demonstrated in the horizontal, vertical, and radial planes of space and has been attributed to sensory-attentional, motor-intentional, and representational deficits, motor intentional neglect in the radial plane has not been previously described. A patient who had a right parietal infarct was tested with a modified cancellation task that uses a fixed window, thereby controlling attentional demands and allowing one to dissociate between intentional and representational neglect. This patient showed proximal (radial) intentional neglect (a failure to move towards or in proximal space). Unlike controls whose search times decreased with increasing window size, our patient showed no change in search time as a function of window size. This pattern of behaviour suggests that the patient's search strategy does not incorporate factors such as the relation between a fixed target space and a variably sized aperture, but rather was based on the allocation of a certain amount of resources for a fixed period of time after which, regardless of performance, the patient would stop searching. PMID:7964818

  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. An improved proximity force approximation for electrostatics

    SciTech Connect

    Fosco, Cesar D.; Lombardo, Fernando C.; Mazzitelli, Francisco D.

    2012-08-15

    A quite straightforward approximation for the electrostatic interaction between two perfectly conducting surfaces suggests itself when the distance between them is much smaller than the characteristic lengths associated with their shapes. Indeed, in the so called 'proximity force approximation' the electrostatic force is evaluated by first dividing each surface into a set of small flat patches, and then adding up the forces due two opposite pairs, the contributions of which are approximated as due to pairs of parallel planes. This approximation has been widely and successfully applied in different contexts, ranging from nuclear physics to Casimir effect calculations. We present here an improvement on this approximation, based on a derivative expansion for the electrostatic energy contained between the surfaces. The results obtained could be useful for discussing the geometric dependence of the electrostatic force, and also as a convenient benchmark for numerical analyses of the tip-sample electrostatic interaction in atomic force microscopes. - Highlights: Black-Right-Pointing-Pointer The proximity force approximation (PFA) has been widely used in different areas. Black-Right-Pointing-Pointer The PFA can be improved using a derivative expansion in the shape of the surfaces. Black-Right-Pointing-Pointer We use the improved PFA to compute electrostatic forces between conductors. Black-Right-Pointing-Pointer The results can be used as an analytic benchmark for numerical calculations in AFM. Black-Right-Pointing-Pointer Insight is provided for people who use the PFA to compute nuclear and Casimir forces.

  14. Proximate determinants of fertility in peninsular Malaysia.

    PubMed

    Tey, Nai Peng; Ng, Sor Tho; Yew, Siew Yong

    2012-05-01

    The continuing decline in fertility despite a contraction in contraceptive use in Peninsular Malaysia since the mid-1980s has triggered considerable interest in the reasons behind this phenomenon, such as increase in abortion, sterility, and out-of-wedlock pregnancy. Fertility decline has been attributed to rapid socioeconomic development, which can only influence fertility through the intermediate variables. Application of vital statistics, population census, and survey data of Peninsular Malaysia on Bongaarts's model vindicates that marriage postponement and contraceptive use are the 2 most important proximate determinants of fertility, but the effects are not uniform across the ethnic groups. For instance, the predicted total fertility rate for Chinese and Malays are 2.9 and 1.6, respectively, compared with the observed level of 3.0 and 1.9. Postpartum infecundability and abortion also play a part in explaining ethnic fertility differentials. The fertility inhibiting effects of these proximate determinants have significant implications on reproductive health and future population growth. PMID:21490114

  15. Obesity and Supermarket Access: Proximity or Price?

    PubMed Central

    Aggarwal, Anju; Hurvitz, Philip M.; Monsivais, Pablo; Moudon, Anne V

    2012-01-01

    Objectives. We examined whether physical proximity to supermarkets or supermarket price was more strongly associated with obesity risk. Methods. The Seattle Obesity Study (SOS) collected and geocoded data on home addresses and food shopping destinations for a representative sample of adult residents of King County, Washington. Supermarkets were stratified into 3 price levels based on average cost of the market basket. Sociodemographic and health data were obtained from a telephone survey. Modified Poisson regression was used to test the associations between obesity and supermarket variables. Results. Only 1 in 7 respondents reported shopping at the nearest supermarket. The risk of obesity was not associated with street network distances between home and the nearest supermarket or the supermarket that SOS participants reported as their primary food source. The type of supermarket, by price, was found to be inversely and significantly associated with obesity rates, even after adjusting for individual-level sociodemographic and lifestyle variables, and proximity measures (adjusted relative risk = 0.34; 95% confidence interval = 0.19, 0.63) Conclusions. Improving physical access to supermarkets may be one strategy to deal with the obesity epidemic; improving economic access to healthy foods is another. PMID:22698052

  16. Proximal interphalangeal joint dislocations without fractures.

    PubMed

    Vicar, A J

    1988-02-01

    Injuries to the proximal interphalangeal joint are extremely common. An understanding of the complex anatomy of this joint is essential for diagnosis and treatment of proximal interphalangeal joint sprains and dislocations. Lateral injuries are among the commonest injuries in the hand. These are often stable after reduction, requiring only closed treatment. Occasionally, however, the collateral ligament can be trapped in the joint and require open reduction. Dorsal dislocations represent the most common dislocation in the hand. These, too, are usually stable after reduction and can be treated by closed methods. On occasion, however, these dislocations will be open or irreducible by closed means, requiring surgical intervention and repair of damaged structures. Complex rotary dislocations are exactly that: complex. An exact understanding of the damaged structures and causes of irreducibility frequently makes this an injury often requiring open reduction and selective repair of damaged soft tissue structures. Fortunately, prompt diagnosis, reduction, and institution of appropriate treatment can usually afford the patient good function after these injuries. It must be noted that stiffness is more common than instability, and active range-of-motion exercises instituted at the proper time are essential. These joints will often remain permanently thicker after injury in spite of optimal care, and tenderness and soreness with use may persist for 6 to 12 months.

  17. 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.

  18. Parallel Proximity Detection for Computer Simulations

    NASA Technical Reports Server (NTRS)

    Steinman, Jeffrey S. (Inventor); Wieland, Frederick P. (Inventor)

    1998-01-01

    The present invention discloses a system for performing proximity detection in computer simulations on parallel processing architectures utilizing a distribution list which includes movers and sensor coverages which check in and out of grids. Each mover maintains a list of sensors that detect the mover's motion as the mover and sensor coverages check in and out of the grids. Fuzzy grids are included by fuzzy resolution parameters to allow movers and sensor coverages to check in and out of grids without computing exact grid crossings. The movers check in and out of grids while moving sensors periodically inform the grids of their coverage. In addition, a lookahead function is also included for providing a generalized capability without making any limiting assumptions about the particular application to which it is applied. The lookahead function is initiated so that risk-free synchronization strategies never roll back grid events. The lookahead function adds fixed delays as events are scheduled for objects on other nodes.

  19. Parallel Proximity Detection for Computer Simulation

    NASA Technical Reports Server (NTRS)

    Steinman, Jeffrey S. (Inventor); Wieland, Frederick P. (Inventor)

    1997-01-01

    The present invention discloses a system for performing proximity detection in computer simulations on parallel processing architectures utilizing a distribution list which includes movers and sensor coverages which check in and out of grids. Each mover maintains a list of sensors that detect the mover's motion as the mover and sensor coverages check in and out of the grids. Fuzzy grids are includes by fuzzy resolution parameters to allow movers and sensor coverages to check in and out of grids without computing exact grid crossings. The movers check in and out of grids while moving sensors periodically inform the grids of their coverage. In addition, a lookahead function is also included for providing a generalized capability without making any limiting assumptions about the particular application to which it is applied. The lookahead function is initiated so that risk-free synchronization strategies never roll back grid events. The lookahead function adds fixed delays as events are scheduled for objects on other nodes.

  20. [Ophthalmologists in the proximity of Adolf Hitler].

    PubMed

    Rohrbach, J M

    2012-10-01

    Adolf Hitler met or at least knew about 5 ophthalmologists. The chair of ophthalmology in Berlin, Walther Löhlein, personally examined Hitler's eyes at least two times. The chair of ophthalmology in Breslau, Walter Dieter, developed "air raid protection spectacles" with the aid of high representatives of the NS-system and probably Adolf Hitler himself. Heinrich Wilhelm Kranz became rector of the universities of Giessen and Frankfurt/Main. He was known as a very strict advocate of the NS-race hygiene. Werner Zabel made plans for Hitler's diet and tried to interfere with Hitler's medical treatment. Finally, Hellmuth Unger was an influential representative of the medical press and a famous writer. Three of his novels with medical topics were made into a film which Hitler probably saw. Hitler had, so to say, a small "ophthalmological proximity" which, however, did not play a significant role for himself or the NS-state. PMID:22664943

  1. [Ophthalmologists in the proximity of Adolf Hitler].

    PubMed

    Rohrbach, J M

    2012-10-01

    Adolf Hitler met or at least knew about 5 ophthalmologists. The chair of ophthalmology in Berlin, Walther Löhlein, personally examined Hitler's eyes at least two times. The chair of ophthalmology in Breslau, Walter Dieter, developed "air raid protection spectacles" with the aid of high representatives of the NS-system and probably Adolf Hitler himself. Heinrich Wilhelm Kranz became rector of the universities of Giessen and Frankfurt/Main. He was known as a very strict advocate of the NS-race hygiene. Werner Zabel made plans for Hitler's diet and tried to interfere with Hitler's medical treatment. Finally, Hellmuth Unger was an influential representative of the medical press and a famous writer. Three of his novels with medical topics were made into a film which Hitler probably saw. Hitler had, so to say, a small "ophthalmological proximity" which, however, did not play a significant role for himself or the NS-state.

  2. Novel superconducting proximized heterostructures for ultrafast photodetection

    NASA Astrophysics Data System (ADS)

    Pepe, G. P.; Parlato, L.; Marrocco, N.; Pagliarulo, V.; Peluso, G.; Barone, A.; Tafuri, F.; Uccio, U. Scotti di; Miletto, F.; Radovic, M.; Pan, D.; Sobolewski, Roman

    2009-11-01

    Weak ferromagnet/superconductor (F/S) proximity bilayers have been fabricated and characterized for basic physics studies concerning the ultrafast carrier dynamics in layered materials. The normalized reflectivity change (Δ R/ R) as a function of the time delay between the pump and the probe laser beams has been measured in F/S heterostructures formed by a low critical temperature superconductor (Nb) with a NiCu overlayer, and a high Tc superconductor (YBCO) covered by Au/NiCu and manganite (LSMO) overlayers. The attention is mainly focused to the investigation of nonequilibrium excitation dynamics inside different bilayers in the low temperature region. The presence of the weak ferromagnetic overlayer produces faster optical relaxation times with respect to sole superconducting films. The results are promising in view of potential applications as ultrafast kinetic inductance superconducting photodetectors as confirmed by preliminary time-resolved photoimpedance experiments on both Nb and NiCu(21 nm)/Nb(70 nm) samples.

  3. Protein structure alignment beyond spatial proximity.

    PubMed

    Wang, Sheng; Ma, Jianzhu; Peng, Jian; Xu, Jinbo

    2013-01-01

    Protein structure alignment is a fundamental problem in computational structure biology. Many programs have been developed for automatic protein structure alignment, but most of them align two protein structures purely based upon geometric similarity without considering evolutionary and functional relationship. As such, these programs may generate structure alignments which are not very biologically meaningful from the evolutionary perspective. This paper presents a novel method DeepAlign for automatic pairwise protein structure alignment. DeepAlign aligns two protein structures using not only spatial proximity of equivalent residues (after rigid-body superposition), but also evolutionary relationship and hydrogen-bonding similarity. Experimental results show that DeepAlign can generate structure alignments much more consistent with manually-curated alignments than other automatic tools especially when proteins under consideration are remote homologs. These results imply that in addition to geometric similarity, evolutionary information and hydrogen-bonding similarity are essential to aligning two protein structures.

  4. Proximity to mining industry and cancer mortality.

    PubMed

    Fernández-Navarro, Pablo; García-Pérez, Javier; Ramis, Rebeca; Boldo, Elena; López-Abente, Gonzalo

    2012-10-01

    Mining installations are releasing toxic substances into the environment which could pose a health problem to populations in their vicinity. We sought to investigate whether there might be excess cancer-related mortality in populations residing in towns lying in the vicinity of Spanish mining industries governed by the Integrated Pollution Prevention and Control Directive, and the European Pollutant Release and Transfer Register Regulation, according to the type of extraction method used. An ecologic study was designed to examine municipal mortality due to 32 types of cancer, across the period 1997 through 2006. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Poisson regression models, using the Bayesian conditional autoregressive model proposed by Besag, York and Molliè and Integrated Nested Laplace Approximations for Bayesian inference, were used: to analyze risk of dying from cancer in a 5-kilometer zone around mining installations; effect of type of industrial activity; and to conduct individual analyses within a 50-kilometer radius of each installation. Excess mortality (relative risk, 95% credible interval) of colorectal cancer (1.097, 1.041-1.157), lung cancer (1.066, 1.009-1.126) specifically related with proximity to opencast coal mining, bladder cancer (1.106, 1.016-1.203) and leukemia (1.093, 1.003-1.191) related with other opencast mining installations, was detected among the overall population in the vicinity of mining installations. Other tumors also associated in the stratified analysis by type of mine, were: thyroid, gallbladder and liver cancers (underground coal installations); brain cancer (opencast coal mining); stomach cancer (coal and other opencast mining installations); and myeloma (underground mining installations). The results suggested an association between risk of dying due to digestive, respiratory, hematologic and thyroid cancers and proximity to Spanish mining

  5. Fixation of proximal humeral prostheses and rotational micromotion.

    PubMed

    Harris, T E; Jobe, C M; Dai, Q G

    2000-01-01

    Twenty pairs of cadaveric humeri were used to compare the rotational stability of proximal humeral prostheses fixed by proximal cementation with the stability offered by press fit or full cementation. For each proximally cemented specimen, only the upper portion of the prosthesis was coated with cement. For the fully cemented specimens, a cement restrictor was used just distal to the prosthesis, and a finger-packing technique was used to fill the proximal humeral medullary canal. Torque was applied to the Morse taper of the prostheses, and rotational micromotion was measured at the level of the osteotomy. In each of 11 pairs of cadaveric humeri, one side was press fit and the contralateral side was proximally cemented; in each of 9 pairs, proximal cementation was compared with full cementation. Proximally cemented prostheses' micromotion was significantly less than that of press-fit prostheses (P = .0016). There was no difference in micromotion between proximal cementation and full cementation (P = .82). Proximal cementation increased initial fixation over press fit. Full cementation did not increase rotational stability.

  6. Vaccination Rates are Associated With Functional Proximity But Not Base Proximity of Vaccination Clinics

    PubMed Central

    Beshears, John; Choi, James J.; Laibson, David I.; Madrian, Brigitte C.

    2016-01-01

    Background: Routine annual influenza vaccinations are recommended for persons 6 months of age and older, but less than half of US adults get vaccinated. Many employers offer employees free influenza vaccinations at workplace clinics, but even then take-up is low. Objective: To determine whether employees are significantly more likely to get vaccinated if they have a higher probability of walking by the clinic for reasons other than vaccination. Method: We obtained data from an employer with a free workplace influenza vaccination clinic. Using each employee’s building entry/exit swipe card data, we test whether functional proximity—the likelihood that the employee walks by the clinic for reasons other than vaccination—predicts whether the employee gets vaccinated at the clinic. We also test whether base proximity—the inverse of walking distance from the employee’s desk to the clinic—predicts vaccination probability. Participants: A total of 1801 employees of a health benefits administrator that held a free workplace influenza vaccination clinic. Results: A 2 SD increase in functional proximity is associated with a 6.4 percentage point increase in the probability of vaccination (total vaccination rate at company=40%), even though the average employee’s desk is only 166 meters from the clinic. Base proximity does not predict vaccination probability. Conclusions and Relevance: Minor changes in the environment can have substantial effects on the probability of vaccination. If these results generalize, health systems should emphasize functional proximity over base proximity when locating preventive health services. PMID:27177295

  7. Short-term nonpressor angiotensin II infusion stimulates sodium transporters in proximal tubule and distal nephron.

    PubMed

    Nguyen, Mien T X; Han, Jiyang; Ralph, Donna L; Veiras, Luciana C; McDonough, Alicia A

    2015-09-01

    In Sprague Dawley rats, 2-week angiotensin II (AngII) infusion increases Na(+) transporter abundance and activation from cortical thick ascending loop of Henle (TALH) to medullary collecting duct (CD) and raises blood pressure associated with a pressure natriuresis, accompanied by depressed Na(+) transporter abundance and activation from proximal tubule (PT) through medullary TALH. This study tests the hypothesis that early during AngII infusion, before blood pressure raises, Na(+) transporters' abundance and activation increase all along the nephron. Male Sprague Dawley rats were infused via osmotic minipumps with a subpressor dose of AngII (200 ng/kg/min) or vehicle for 3 days. Overnight urine was collected in metabolic cages and sodium transporters' abundance and phosphorylation were determined by immunoblotting homogenates of renal cortex and medulla. There were no significant differences in body weight gain, overnight urine volume, urinary Na(+) and K(+) excretion, or rate of excretion of a saline challenge between AngII and vehicle infused rats. The 3-day nonpressor AngII infusion significantly increased the abundance of PT Na(+)/H(+) exchanger 3 (NHE3), cortical TALH Na-K-2Cl cotransporter 2 (NKCC2), distal convoluted tubule (DCT) Na-Cl cotransporter (NCC), and cortical CD ENaC subunits. Additionally, phosphorylation of cortical NKCC2, NCC, and STE20/SPS1-related proline-alanine-rich kinase (SPAK) were increased; medullary NKCC2 and SPAK were not altered. In conclusion, 3-day AngII infusion provokes PT NHE3 accumulation as well as NKCC2, NCC, and SPAK accumulation and activation in a prehypertensive phase before evidence for intrarenal angiotensinogen accumulation. PMID:26347505

  8. Loss of tubular creatinine secretion as the only sign of tubular proximal cell dysfunction in light chain proximal tubulopathy

    PubMed Central

    Stehlé, Thomas; Vignon, Marguerite; Flamant, Martin; Figueres, Marie-Lucile; Rabant, Marion; Rodenas, Anita; Noël, Laure-Hélène; Arnulf, Bertrand; Vidal-Petiot, Emmanuelle

    2016-01-01

    Abstract Light chain proximal tubulopathy (LCPT) is a rare disease, characterized by cytoplasmic inclusions of light chain (usually kappa) immunoglobulins. Clinical presentation is usually a Fanconi syndrome. The proximal tubular dysfunction can be incomplete, and exceptional cases of LCPT without any tubular dysfunction have even been described. Here, we report a case of LCPT in which the only sign of proximal tubulopathy is the absence of secretion of creatinine, as assessed by the simultaneous measurement of renal clearance of creatinine and 51CrEDTA. The loss of tubular creatinine secretion as a sign of tubular proximal cell dysfunction ought to be identified in patients with light chain proximal tubulopathy as it leads to a clinically relevant underestimation of GFR by the creatinine-derived equations. The prevalence and prognostic significance of this particular proximal tubular damage in LCPT remain to be determined. PMID:27367983

  9. Proximity Operations and Docking Sensor Development

    NASA Technical Reports Server (NTRS)

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

    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 Sensor (AVGS) as the primary docking sensor. That flight proved that the United States now has a mature and flight proven sensor technology for supporting Crew Exploration Vehicles (CEV) and Commercial Orbital Transport Systems (COTS) Automated Rendezvous and Docking (AR&D). NASA video sensors have worked well in the past: the AVGS used on the Demonstration of Autonomous Rendezvous Technology (DART) mission operated successfully in spot mode out to 2 km, and the first generation rendezvous and docking sensor, the Video Guidance Sensor (VGS), was developed and successfully flown on Space Shuttle flights in 1997 and 1998. 12 Parts obsolescence issues prevent the construction of more AVGS units, and the next generation sensor was updated to allow it to support the CEV and COTS programs. The flight proven AR&D sensor has been redesigned to update parts and add additional capabilities for CEV and COTS with the development of the Next Generation AVGS at the Marshall Space Flight Center. The obsolete imager and processor are being replaced with new radiation tolerant parts. In addition, new capabilities include greater sensor range, auto ranging capability, and real-time video output. This paper presents some sensor hardware trades, use of highly integrated laser components, and addresses the needs of future vehicles that may rendezvous and dock with the International Space Station (ISS) and other Constellation vehicles. It also discusses approaches for upgrading AVGS to address parts obsolescence, and concepts for minimizing the sensor footprint, weight, and power requirements

  10. Role of TASK2 potassium channels regarding volume regulation in primary cultures of mouse proximal tubules.

    PubMed

    Barriere, Herve; Belfodil, Radia; Rubera, Isabelle; Tauc, Michel; Lesage, Florian; Poujeol, Chantal; Guy, Nicolas; Barhanin, Jacques; Poujeol, Philippe

    2003-08-01

    Several papers reported the role of TASK2 channels in cell volume regulation and regulatory volume decrease (RVD). To check the possibility that the TASK2 channel modulates the RVD process in kidney, we performed primary cultures of proximal convoluted tubules (PCT) and distal convoluted tubules (DCT) from wild-type and TASK2 knockout (KO) mice. In KO mice, the TASK2 coding sequence was in part replaced by the lac-Z gene. This allows for the precise localization of TASK2 in kidney sections using beta-galactosidase staining. TASK2 was only localized in PCT cells. K+ currents were analyzed by the whole-cell clamp technique with 125 mM K-gluconate in the pipette and 140 mM Na-gluconate in the bath. In PCT cells from wild-type mice, hypotonicity induced swelling-activated K+ currents insensitive to 1 mM tetraethylammonium, 10 nM charybdotoxin, and 10 microM 293B, but blocked by 500 microM quinidine and 10 microM clofilium. These currents were increased in alkaline pH and decreased in acidic pH. In PCT cells from TASK2 KO, swelling-activated K+ currents were completely impaired. In conclusion, the TASK2 channel is expressed in kidney proximal cells and could be the swelling-activated K+ channel responsible for the cell volume regulation process during osmolyte absorptions in the proximal tubules. PMID:12860925

  11. 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.

  12. Anatomic Reconstruction of the Proximal Tibiofibular Joint.

    PubMed

    Warner, Brent T; Moulton, Samuel G; Cram, Tyler R; LaPrade, Robert F

    2016-02-01

    Proximal tibiofibular joint (PTFJ) instability can be easily missed or confused for other, more common lateral knee pathologies such as meniscal tears, fibular collateral ligament injury, biceps femoris pathology, or iliotibial band syndrome. Because of this confusion, some authors believe that PTFJ instability is more common than initially appreciated. Patients with PTFJ subluxation may have no history of inciting trauma or injury, and it is not uncommon for these patients to have bilateral symptoms and generalized ligamentous laxity. Currently, the optimal surgical treatment for patients with chronic PTFJ instability is unknown. Historically, a variety of surgical treatments have been reported. Initially, joint arthrodesis and fibular head resection were recommended. More recently, temporary screw fixation, nonanatomic reconstruction with strips of the biceps femoris tendon or iliotibial band, and reconstruction with free hamstring autograft have been described. The purpose of this report is to present our surgical technique for treatment of chronic PTFJ instability using an anatomic reconstruction of the posterior ligamentous structures of the PTFJ with a semitendinosus autograft. PMID:27274455

  13. Proximity Resonance and Localized Surface Plasmons

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Heller, Eric

    2014-03-01

    The collective excitation of conduction electrons in subwavelength nanostructures is known as Localized Surface Plasmon(LSP)[1]. Such plasmon modes has been intensively studied using noble nanoparticles . More recently, the possibility of building terahertz metamaterials supporting such LSP modes has been explored in graphene microribbons and microdisks. Unlike Surface Plasmon Polaritons(SPPs) at metal-insulator interface, LSP can be directly excited by light illumination and holds promise for applications in ultrasensitive biosensing, nano-optical tweezers and improved photovoltaic devices. In this paper, we consider the interaction of two LSPs in the weak coupling regime and show how an effect similar to the proximity resonance in the quantum scattering theory) gives rise to an asymmetric(quadrupole) mode with increased damping rate. The existence of this asymmetric mode relies on a small phase retardation between the two LSPs. This phase retardation, though small, is key to both increased damping rate for the asymmetric mode and reduced damping rate for the symmetric mode. When this small phase retardation is removed by changing the polarization of the exciting light,we show that the asymmetric mode can not be excited and the symmetric mode shows increased damping.

  14. 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.

  15. Effects of thrust reversing in ground proximity

    NASA Technical Reports Server (NTRS)

    Joshi, P. B.; Hughes, R. V.

    1987-01-01

    The changes in stability and control characteristics encountered by a thrust reversing aircraft during its final approach, landing, and ground roll are described. These changes include a strong pitch-up accompanied by the loss of horizontal tail and aileron control effectiveness. The magnitude of reverser induced changes in ground effect are much larger than corresponding changes in free air. Some unexpected unsteady motions exhibited in wind tunnel by an aircraft model with reversers operating in ground proximity are also described. The cause of this oscillatory behavior was determined to be an unsteady interaction between the wall jets formed by impingement of reverser jets on the ground and the on-coming free stream. Time histories of rolling moments measured by the wind tunnel balance or support system were removed and frequencies were scaled by Strouhal number to full scale. Corrected time series were used to simulate the motion of a fighter aircraft with thrust reversers in ground effect. The simulation predicted large roll angles and nose down attitude at touchdown. Some phenomena of jet attachment to solid surfaces are discussed and areas for future research are recommended.

  16. Semiconductor detectors with proximity signal readout

    SciTech Connect

    Asztalos, Stephen J.

    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.

  17. Ranging/tracking system for proximity operations

    NASA Technical Reports Server (NTRS)

    Nilsen, P.; Udalov, S.

    1982-01-01

    The hardware development and testing phase of a hand held radar for the ranging and tracking for Shuttle proximity operations are considered. The radar is to measure range to a 3 sigma accuracy of 1 m (3.28 ft) to a maximum range of 1850 m (6000 ft) and velocity to a 3 sigma accuracy of 0.03 m/s (0.1 ft/s). Size and weight are similar to hand held radars, frequently seen in use by motorcycle police officers. Meeting these goals for a target in free space was very difficult to obtain in the testing program; however, at a range of approximately 700 m, the 3 sigma range error was found to be 0.96 m. It is felt that much of this error is due to clutter in the test environment. As an example of the velocity accuracy, at a range of 450 m, a 3 sigma velocity error of 0.02 m/s was measured. The principles of the radar and recommended changes to its design are given. Analyses performed in support of the design process, the actual circuit diagrams, and the software listing are included.

  18. Scintillation Proximity Assay of Arginine Methylation

    PubMed Central

    Wu, Jiang; Xie, Nan; Feng, You; Zheng, Y. George

    2011-01-01

    Methylation of arginine residues, catalyzed by protein arginine methyltransferases (PRMTs), is one important protein post-translational modification involved in epigenetic regulation of gene expression. A fast and effective assay for PRMT can provide valuable information for dissecting the biological functions of PRMTs, as well as for screening small-molecule inhibitors of arginine methylation. Currently, among the methods used for PRMT activity measurement, many contain laborious separation procedures, which restrict the applications of these assays for high-throughput screening (HTS) in drug discovery. The authors report here a mix-and-measure method to measure PRMT activity based on the principle of scintillation proximity assay (SPA). In this assay, 3H-AdoMet was used as methyl donor, and biotin-modified histone H4 peptide served as a methylation substrate. Following the methylation reaction catalyzed by PRMTs, streptavidin-coated SPA beads were added to the reaction solution, and SPA signals were detected by a MicroBeta scintillation counter. No separation step is needed, which simplifies the assay procedure and greatly enhances the assay speed. Particularly, the miniaturization and robustness suggest that this method is suited for HTS of PRMT inhibitors. PMID:21821785

  19. Proximal spinal muscular atrophy: current orthopedic perspective

    PubMed Central

    Haaker, Gerrit; Fujak, Albert

    2013-01-01

    Spinal muscular atrophy (SMA) is a hereditary neuromuscular disease of lower motor neurons that is caused by a defective “survival motor neuron” (SMN) protein that is mainly associated with proximal progressive muscle weakness and atrophy. Although SMA involves a wide range of disease severity and a high mortality and morbidity rate, recent advances in multidisciplinary supportive care have enhanced quality of life and life expectancy. Active research for possible treatment options has become possible since the disease-causing gene defect was identified in 1995. Nevertheless, a causal therapy is not available at present, and therapeutic management of SMA remains challenging; the prolonged survival is increasing, especially orthopedic, respiratory and nutritive problems. This review focuses on orthopedic management of the disease, with discussion of key aspects that include scoliosis, muscular contractures, hip joint disorders, fractures, technical devices, and a comparative approach of conservative and surgical treatment. Also emphasized are associated complications including respiratory involvement, perioperative care and anesthesia, nutrition problems, and rehabilitation. The SMA disease course can be greatly improved with adequate therapy with established orthopedic procedures in a multidisciplinary therapeutic approach. PMID:24399883

  20. Dynamic proximity of spatio-temporal sequences.

    PubMed

    Horn, David; Dror, Gideon; Quenet, Brigitte

    2004-09-01

    Recurrent networks can generate spatio-temporal neural sequences of very large cycles, having an apparent random behavior. Nonetheless a proximity measure between these sequences may be defined through comparison of the synaptic weight matrices that generate them. Following the dynamic neural filter (DNF) formalism we demonstrate this concept by comparing teacher and student recurrent networks of binary neurons. We show that large sequences, providing a training set well exceeding the Cover limit, allow for good determination of the synaptic matrices. Alternatively, assuming the matrices to be known, very fast determination of the biases can be achieved. Thus, a spatio-temporal sequence may be regarded as spatio-temporal encoding of the bias vector. We introduce a linear support vector machine (SVM) variant of the DNF in order to specify an optimal weight matrix. This approach allows us to deal with noise. Spatio-temporal sequences generated by different DNFs with the same number of neurons may be compared by calculating correlations of the synaptic matrices of the reconstructed DNFs. Other types of spatio-temporal sequences need the introduction of hidden neurons, and/or the use of a kernel variant of the SVM approach. The latter is being defined as a recurrent support vector network (RSVN).

  1. Proximity Navigation of Highly Constrained Spacecraft

    NASA Technical Reports Server (NTRS)

    Scarritt, S.; Swartwout, M.

    2007-01-01

    Bandit is a 3-kg automated spacecraft in development at Washington University in St. Louis. Bandit's primary mission is to demonstrate proximity navigation, including docking, around a 25-kg student-built host spacecraft. However, because of extreme constraints in mass, power and volume, traditional sensing and actuation methods are not available. In particular, Bandit carries only 8 fixed-magnitude cold-gas thrusters to control its 6 DOF motion. Bandit lacks true inertial sensing, and the ability to sense position relative to the host has error bounds that approach the size of the Bandit itself. Some of the navigation problems are addressed through an extremely robust, error-tolerant soft dock. In addition, we have identified a control methodology that performs well in this constrained environment: behavior-based velocity potential functions, which use a minimum-seeking method similar to Lyapunov functions. We have also adapted the discrete Kalman filter for use on Bandit for position estimation and have developed a similar measurement vs. propagation weighting algorithm for attitude estimation. This paper provides an overview of Bandit and describes the control and estimation approach. Results using our 6DOF flight simulator are provided, demonstrating that these methods show promise for flight use.

  2. Effect of Peritubular Protein Concentration on Reabsorption of Sodium and Water in Isolated Perfused Proximal Tubules

    PubMed Central

    Imai, Masashi; Kokko, Juha P.

    1972-01-01

    Micropuncture studies have indicated that variation in peritubular oncotic pressure influences net transport of fluid out of the proximal tubule. The present in vitro studies on isolated perfused rabbit proximal convoluted tubules were designed to examine whether protein concentration gradient must act across the peritubular capillary membrane to influence reabsorption, or whether it can exert a direct effect across the tubular basement membrane 71 proximal tubules were perfused with ultrafiltrate made isosmolal to bathing fluids, the latter having identical electrolyte composition as the perfusing ultrafiltrate, but adjusted to three oncotic pressures: hypooncotic, protein 0.0 g/100 ml; control isooncotic serum, protein 6.4 g/100 ml; and hyperoncotic, protein 12.5 g/100 ml. Net volume flux (nl/mm per min), net Na flux (nEq/mm per min), unidirectional Na flux from bath to lumen (nEq/mm per min), and passive permeability coefficient (× 10-5 cm/sec) for Na (PNa), urea (Purea), and sucrose (Psucrose) were determined using isotopic techniques. When the bath was hypooncotic, there was (as compared with isooncotic serum) a significant decrease in net volume (38%) and net sodium (40%) flux, but no change in PNa, Purea, or transtubular potential; however, Psucrose increased significantly (78%). In experiments in which hyperoncotic bath was used, there was (compared with isooncotic serum) an increase in net volume (28%) and net sodium (30%) flux, but transtubular potential difference did not change significantly. These data demonstrated that changes in the ambient protein concentration gradient exert direct effects upon proximal tubular reabsorption. Because penetration of sucrose (an index of intercellular movement) but not urea (an index of transcellular movement) varied with changes in tubular reabsorption, it is suggested that oncotic pressure acts by altering the rate of back-leak of reabsorbate through extracellular pathways between tubular cells. It is concluded

  3. Proximate and ultimate causes of punishment and strong reciprocity.

    PubMed

    Barclay, Pat

    2012-02-01

    While admirable, Guala's discussion of reciprocity suffers from a confusion between proximate causes (psychological mechanisms triggering behaviour) and ultimate causes (evolved function of those psychological mechanisms). Because much work on "strong reciprocity" commits this error, I clarify the difference between proximate and ultimate causes of cooperation and punishment. I also caution against hasty rejections of "wide readings" of experimental evidence.

  4. Analysis of pattern density on process proximity compensation

    NASA Astrophysics Data System (ADS)

    Jung, Sunwook; Lo, Fred; Yang, Tien-Chu; Yang, Ta-Hong; Chen, Kuang-Chao; Lu, Chih-Yuan

    2007-03-01

    The challenges of ever-smaller CD (Critical Dimension) budget for advanced memory product requires tight ACLV (Across-Chip Line-width Variation) control. In addition to the lithographic MOPC (Model-based Optical Proximity Correction) for DCD (photo CD) control, the process correction for etch proximity effect can no longer be ignored. To meet on our requirement on final CD accuracy for critical layer, a set of test pattern, that represents memory array in one of our critical layers, has been generated for both photo and etch process characterizations. Through the combination of different pattern-coverage areas in the test mask and wafer map design, various local (chip-level) pattern densities of 40%~70% and global (wafer-level) pattern densities of 35%~65% were achieved for optical and etch proximity study. The key contributors to the process proximity effect were identified and voluminous data has been extracted from the memory block like patterns for statistical analysis. The photo and etch proximity effects were hence modeled as function of memory block separation, local pattern density as well as global pattern density. Finally, the respective photo and etch proximity effects through model-based proximity correction and rule-based proximity correction were applied in a multi-step flow to products.

  5. Intracellular Na+ regulates epithelial Na+ channel maturation.

    PubMed

    Heidrich, Elisa; Carattino, Marcelo D; Hughey, Rebecca P; Pilewski, Joseph M; Kleyman, Thomas R; Myerburg, Mike M

    2015-05-01

    Epithelial Na(+) channel (ENaC) function is regulated by the intracellular Na(+) concentration ([Na(+)]i) through a process known as Na(+) feedback inhibition. Although this process is known to decrease the expression of proteolytically processed active channels on the cell surface, it is unknown how [Na(+)]i alters ENaC cleavage. We show here that [Na(+)]i regulates the posttranslational processing of ENaC subunits during channel biogenesis. At times when [Na(+)]i is low, ENaC subunits develop mature N-glycans and are processed by proteases. Conversely, glycan maturation and sensitivity to proteolysis are reduced when [Na(+)]i is relatively high. Surface channels with immature N-glycans were not processed by endogenous channel activating proteases, nor were they sensitive to cleavage by exogenous trypsin. Biotin chase experiments revealed that the immature surface channels were not converted into mature cleaved channels following a reduction in [Na(+)]i. The hypothesis that [Na(+)]i regulates ENaC maturation within the biosynthetic pathways is further supported by the finding that Brefeldin A prevented the accumulation of processed surface channels following a reduction in [Na(+)]i. Therefore, increased [Na(+)]i interferes with ENaC N-glycan maturation and prevents the channel from entering a state that allows proteolytic processing. PMID:25767115

  6. Molecular interactions between albumin and proximal tubular cells.

    PubMed

    Brunskill, N J

    1998-01-01

    In glomerular diseases the filtration of excess proteins into the proximal tubule, together with their subsequent reabsorption may represent an important pathological mechanism underlying progressive renal scarring. The most prominent protein in glomerular filtrate, albumin, is reabsorbed by receptor-mediated endocytosis by proximal tubular cells. It binds both to scavenger-type receptors and to megalin in the proximal tubule. Some of these receptors appear to be shared with other cell types, particularly endothelial cells. The endocytic uptake of albumin is subjected to complex hormonal and enzymatic regulation. In addition to being reabsorbed in the proximal tubule, albumin may act as a signalling molecule in these cells, and may induce the expression of numerous pro-inflammatory genes. Modulation of the interaction of albumin with proximal tubular cells may eventually prove to be of therapeutic importance in the treatment of renal diseases. PMID:9807019

  7. Mechanisms of albumin uptake by proximal tubular cells.

    PubMed

    Brunskill, N

    2001-01-01

    The likely role of albumin in the induction tubulo-interstitial injury in proteinuria has stimulated considerable interest in the entry of albumin into the proximal tubule and its subsequent uptake by proximal tubular cells. Currently, there is considerable controversy over the degree of glomerular permeability to albumin. After filtration, however, albumin binds to megalin and cubulin, two giant receptors in the apical membrane of proximal tubular cells. Albumin is subsequently re-absorbed by proximal tubular cells by receptor-mediated endocytosis, a process subject to complex regulation. The interaction of albumin with proximal tubule cells also leads to the generation of intracellular signals. The understanding of these pathways may provide important insights into the pathogenesis of renal scarring in proteinuria. PMID:11158855

  8. 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.

  9. Nanocrystal Bioassembly: Asymmetry, Proximity, and Enzymatic Manipulation

    SciTech Connect

    Claridge, Shelley A.

    2008-05-01

    Research at the interface between biomolecules and inorganic nanocrystals has resulted in a great number of new discoveries. In part this arises from the synergistic duality of the system: biomolecules may act as self-assembly agents for organizing inorganic nanocrystals into functional materials; alternatively, nanocrystals may act as microscopic or spectroscopic labels for elucidating the behavior of complex biomolecular systems. However, success in either of these functions relies heavily uponthe ability to control the conjugation and assembly processes.In the work presented here, we first design a branched DNA scaffold which allows hybridization of DNA-nanocrystal monoconjugates to form discrete assemblies. Importantly, the asymmetry of the branched scaffold allows the formation of asymmetric2assemblies of nanocrystals. In the context of a self-assembled device, this can be considered a step toward the ability to engineer functionally distinct inputs and outputs.Next we develop an anion-exchange high performance liquid chromatography purification method which allows large gold nanocrystals attached to single strands of very short DNA to be purified. When two such complementary conjugates are hybridized, the large nanocrystals are brought into close proximity, allowing their plasmon resonances to couple. Such plasmon-coupled constructs are of interest both as optical interconnects for nanoscale devices and as `plasmon ruler? biomolecular probes.We then present an enzymatic ligation strategy for creating multi-nanoparticle building blocks for self-assembly. In constructing a nanoscale device, such a strategy would allow pre-assembly and purification of components; these constructs can also act as multi-label probes of single-stranded DNA conformational dynamics. Finally we demonstrate a simple proof-of-concept of a nanoparticle analog of the polymerase chain reaction.

  10. Mechanisms of proximal tubule sodium transport regulation that link extracellular fluid volume and blood pressure.

    PubMed

    McDonough, Alicia A

    2010-04-01

    One-hundred years ago, Starling articulated the interdependence of renal control of circulating blood volume and effective cardiac performance. During the past 25 years, the molecular mechanisms responsible for the interdependence of blood pressure (BP), extracellular fluid volume (ECFV), the renin-angiotensin system (RAS), and sympathetic nervous system (SNS) have begun to be revealed. These variables all converge on regulation of renal proximal tubule (PT) sodium transport. The PT reabsorbs two-thirds of the filtered Na(+) and volume at baseline. This fraction is decreased when BP or perfusion pressure is increased, during a high-salt diet (elevated ECFV), and during inhibition of the production of ANG II; conversely, this fraction is increased by ANG II, SNS activation, and a low-salt diet. These variables all regulate the distribution of the Na(+)/H(+) exchanger isoform 3 (NHE3) and the Na(+)-phosphate cotransporter (NaPi2), along the apical microvilli of the PT. Natriuretic stimuli provoke the dynamic redistribution of these transporters along with associated regulators, molecular motors, and cytoskeleton-associated proteins to the base of the microvilli. The lipid raft-associated NHE3 remains at the base, and the nonraft-associated NaPi2 is endocytosed, culminating in decreased Na(+) transport and increased PT flow rate. Antinatriuretic stimuli return the same transporters and regulators to the body of the microvilli associated with an increase in transport activity and decrease in PT flow rate. In summary, ECFV and BP homeostasis are, at least in part, maintained by continuous and acute redistribution of transporter complexes up and down the PT microvilli, which affect regulation of PT sodium reabsorption in response to fluctuations in ECFV, BP, SNS, and RAS. PMID:20106993

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

    PubMed

    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

    2014-03-01

    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.

  12. Coordinated regulation of cardiac Na(+)/Ca (2+) exchanger and Na (+)-K (+)-ATPase by phospholemman (FXYD1).

    PubMed

    Cheung, Joseph Y; Zhang, Xue-Qian; Song, Jianliang; Gao, Erhe; Chan, Tung O; Rabinowitz, Joseph E; Koch, Walter J; Feldman, Arthur M; Wang, JuFang

    2013-01-01

    Phospholemman (PLM) is the founding member of the FXYD family of regulators of ion transport. PLM is a 72-amino acid protein consisting of the signature PFXYD motif in the extracellular N terminus, a single transmembrane (TM) domain, and a C-terminal cytoplasmic tail containing three phosphorylation sites. In the heart, PLM co-localizes and co-immunoprecipitates with Na(+)-K(+)-ATPase, Na(+)/Ca(2+) exchanger, and L-type Ca(2+) channel. The TM domain of PLM interacts with TM9 of the α-subunit of Na(+)-K(+)-ATPase, while its cytoplasmic tail interacts with two small regions (spanning residues 248-252 and 300-304) of the proximal intracellular loop of Na(+)/Ca(2+) exchanger. Under stress, catecholamine stimulation phosphorylates PLM at serine(68), resulting in relief of inhibition of Na(+)-K(+)-ATPase by decreasing K(m) for Na(+) and increasing V(max), and simultaneous inhibition of Na(+)/Ca(2+) exchanger. Enhanced Na(+)-K(+)-ATPase activity lowers intracellular Na(+), thereby minimizing Ca(2+) overload and risks of arrhythmias. Inhibition of Na(+)/Ca(2+) exchanger reduces Ca(2+) efflux, thereby preserving contractility. Thus, the coordinated actions of PLM during stress serve to minimize arrhythmogenesis and maintain inotropy. In acute cardiac ischemia and chronic heart failure, either expression or phosphorylation of PLM or both are altered. PLM regulates important ion transporters in the heart and offers a tempting target for development of drugs to treat heart failure.

  13. Open reduction and internal fixation of proximal humerus fractures.

    PubMed

    Drosdowech, Darren S; Faber, Kenneth J; Athwal, George S

    2008-10-01

    Open reduction of proximal humeral fractures has the advantage of providing direct control over each fracture fragment and permitting anatomic reduction and fixation with advanced devices. Modern fixed-angle locking plates designed specifically for proximal humerus fractures have allowed the expansion of surgical indications permitting surgeons to address more complicated fractures. Advanced preoperative imaging and fluoroscopy allow a better understanding of fracture patterns and permit the surgeon to use this knowledge intraoperatively. Research is required to further validate fracture classification systems, to develop surgical guidelines for decision making, and to compare the outcomes of the various treatments options for proximal humerus fractures.

  14. Split biceps femoris tendon reconstruction for proximal tibiofibular joint instability.

    PubMed

    Mena, H; Brautigan, B; Johnson, D L

    2001-07-01

    Recurrent instability of the proximal tibiofibular joint is an infrequently diagnosed abnormality. We present a new technique for reconstructing the joint using a split biceps femoris tendon passed through a bone tunnel in both the proximal tibial metaphysis and fibular head. The case report is also presented. The procedure offers an anatomic reconstruction and firm stabilization. It allows normal motion of the proximal tibiofibular joint and preserves the normal mechanics of the ankle. This procedure is an excellent alternative to resection of the fibular head, transarticular arthrodesis, or pseudoarthrosis focus at the fibular head.

  15. Contributions of cellular leak pathways to net NaHCO3 and NaCl absorption.

    PubMed Central

    Preisig, P A; Alpern, R J

    1989-01-01

    Proton and formic acid permeabilities were measured in the in vivo microperfused rat proximal convoluted tubule by examining the effect on intracellular pH when [H] and/or [formic acid] were rapidly changed in the luminal or peritubular fluids. Apical and basolateral membrane H permeabilities were 0.52 +/- 0.07 and 0.67 +/- 0.18 cm/s, respectively. Using these permeabilities we calculate that proton backleak from the luminal fluid to cell does not contribute significantly to net proton secretion in the early proximal tubule, but may contribute in the late proximal tubule. Apical and basolateral membrane formic acid permeabilities measured at extracellular pH 6.62 were 4.6 +/- 0.5 X 10(-2) and 6.8 +/- 1.5 X 10(-2) cm/s, respectively. Control studies demonstrated that the formic acid permeabilities were not underestimated by either the simultaneous movement of formate into the cell or the efflux of formic acid across the opposite membrane. The measured apical membrane formic acid permeability is too small to support all of transcellular NaCl absorption in the rat by a mechanism that involves Na/H-Cl/formate transporters operating in parallel with formic acid nonionic diffusion. PMID:2542374

  16. Light-operated proximity detector with linear output

    DOEpatents

    Simpson, M.L.; McNeilly, D.R.

    1984-01-01

    A light-operated proximity detector is described in which reflected light intensity from a surface whose proximity to the detector is to be gauged is translated directly into a signal proportional to the distance of the detector from the surface. A phototransistor is used to sense the reflected light and is connected in a detector circuit which maintains the phtotransistor in a saturated state. A negative feedback arrangement using an operational amplifier connected between the collector and emitter of the transistor provides an output at the output of the amplifier which is linearly proportional to the proximity of the surface to the detector containing the transistor. This direct proportional conversion is true even though the light intensity is varying with the proximity in proportion to the square of the inverse of the distance. The detector may be used for measuring the distance remotely from any target surface.

  17. Light-operated proximity detector with linear output

    DOEpatents

    Simpson, Marc L.; McNeilly, David R.

    1985-01-01

    A light-operated proximity detector is described in which reflected light intensity from a surface whose proximity to the detector is to be gauged is translated directly into a signal proportional to the distance of the detector from the surface. A phototransistor is used to sense the reflected light and is connected in a detector circuit which maintains the phototransistor in a saturated state. A negative feedback arrangement using an operational amplifier connected between the collector and emitter of the transistor provides an output at the output of the amplifier which is linearly proportional to the proximity of the surface to the detector containing the transistor. This direct proportional conversion is true even though the light intensity is varying with the proximity in proportion to the square of the inverse of the distance. The detector may be used for measuring the distance remotely from any target surface.

  18. Proximity superconductivity in ballistic graphene at high magnetic fields

    NASA Astrophysics Data System (ADS)

    Prance, J. R.; Ben Shalom, M.; Zhu, M. J.; Fal'Ko, V. I.; Mishchenko, A.; Kretinin, A. V.; Novoselov, K. S.; Woods, C. R.; Watanabe, K.; Taniguchi, T.; Geim, A. K.

    We present measurements of the superconducting proximity effect in graphene-based Josephson junctions with a mean free path of several microns, which exceeds the junctions' length. The junctions exhibit low contact resistance and large supercurrents. We observe Fabry-Pérot oscillations in the normal-state resistance and the critical current of the junctions. The proximity effect is mostly suppressed in magnetic fields of <10 mT showing the conventional Fraunhofer interference pattern; however, unexpectedly, a weak proximity effect survives in magnetic fields as high as 1 T. Superconducting states randomly appear and disappear as a function of field and carrier concentration, and each exhibits a supercurrent carrying capacity close to the universal limit of e Δ/h where Δ is the superconducting gap of the contacts. We attribute the high-field supercurrent to mesoscopic Andreev states that persist near graphene edges. Our work reveals new proximity regimes that can be controlled by quantum confinement and cyclotron motion.

  19. Existence of best proximity pairs and equilibrium pairs

    NASA Astrophysics Data System (ADS)

    Kim, Won Kyu; Lee, Kyoung Hee

    2006-04-01

    In this paper, using the fixed point theorem for Kakutani factorizable multifunctions, we shall prove new existence theorems of best proximity pairs and equilibrium pairs for free abstract economies, which include the previous fixed point theorems and equilibrium existence theorems.

  20. 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.

  1. Proportional proximity sensing for telerobots using Coherent Laser Radar

    NASA Technical Reports Server (NTRS)

    Vazquez, Sixto L.; Goode, Plesent W.; Slotwinski, Anthony R.

    1992-01-01

    The ability of a telerobotic manipulator to operate in confined spaces while avoiding unwanted collisions is enhanced by the accurate sensing of its proximate environment. To achieve the fidelity required for precise manipulator control, a proportional proximity sensor system with a sufficiently large measurement envelope is required. Current proximity sensors provide a binary indication of the presence of obstacles within a small envelope with coarse or no proportional measurement of their location. A proportional proximity sensor system configured as a Frequency Modulated Continuous Wave (FMCW) Coherent Laser Radar (CLR) using a semiconductor laser as the energy source is described and analyzed. The source and reflected energies mix coherently to generate a radio frequency (RF) signal whose frequency is proportional to the range. The system is tested for accuracy, range, depth of range, speed, and sensitivity and the results are presented. Techniques to derive orientation information and an application to telerobotic control are also described.

  2. 1. General view to southwest showing proximity of house to ...

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

    1. General view to southwest showing proximity of house to bridge and north elevation of house. - Locke Avenue Bridge, Bridge Tender's House, East side of Locke Avenue, 12 feet south of Locke Avenue Bridge, Swedesboro, Gloucester County, NJ

  3. 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

  4. Evaluation and management of pediatric proximal humerus fractures.

    PubMed

    Popkin, Charles A; Levine, William N; Ahmad, Christopher S

    2015-02-01

    In the pediatric population, sports participation, falls, and motor vehicle accidents can result in proximal humerus fractures. Because the proximal humeral growth plate is responsible for up to 80% of the growth of the humerus, the remodeling of these fractures in children is tremendous. Most of these injuries can be treated with a sling or hanging arm cast, although older children with decreased remodeling capacity may require surgery. Special considerations should be taken for management of proximal humerus fractures that occur in the context of Little League shoulder, lesser tuerosity avulsion fractures, fracture-dislocations, birth fractures, and fractures associated with cysts. Most pediatric patients with proximal humerus fractures have favorable results, and complications are infrequent.

  5. 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)

  6. Analysis on the characteristics of pulsed laser proximity fuze's echo

    NASA Astrophysics Data System (ADS)

    Wang, Kun; Chen, Huimin

    2011-06-01

    With the rapid development of semiconductor technology and laser technology, a kind of proximity fuze named pulsed laser proximity fuze has been applied. Compared with other fuzes, pulsed laser proximity fuze has high ranging precision and strong resistance to artificial active interference. It is an important development tendency of proximity fuze. The paper analyze the characteristic of target echo of laser signal, and then make theoretical analysis and calculation on the laser signal transmission in the smog. Firstly, use the pulse width of 10ns semiconductor laser fuze to do typical targets experiment, to get the echo information of target distance is 5m; then to do smog interference experiment, by comparing the pulse width amplitude and backscattering signal amplitude of laser fuze in simulation and experiment, analyzing the effect of anti-clutter, providing the evidence for the subsequent of circuit of signal amplification and processing.

  7. Proximal row carpectomy with or without postoperative immobilisation.

    PubMed

    Jacobs, R; Degreef, I; De Smet, L

    2008-12-01

    Previously published reports have shown good results after proximal row carpectomy in all cases that had a postoperative immobilisation period from 1 to 4 weeks. Immobilisation is thought to be necessary because of the risk of postoperative subluxation of the carpus and for pain relief. There is, however, no evidence of its value. The results in 13 patients who underwent proximal row carpectomy without postoperative immobilisation were compared with those in 25 patients who underwent proximal row carpectomy with postoperative immobilisation for 4 weeks. After a mean follow-up period of 27 months, no significant differences were found for pain, range of motion or return to work between the two groups. We conclude that postoperative immobilisation is not necessary after proximal row carpectomy.

  8. [Merle D'Aubigne's oblique proximal femoral osteotomy. Surgical technique].

    PubMed

    López Sosa, Francisco H; Valentín-Guerrero, Santiago; Miranda-López, Eduardo

    2008-01-01

    Proximal femoral osteotomy with the technique described by Merle D'AubignC and Valliant was used in the treatment of adult patients with osteoarthritis or idiopathic avascular necrosis. Dr. Antonio Flores applied this technique to children with subluxation and acetabular dysplasia, identified with exaggerated anteversion and valgus of the proximal femur. He reported correction of the deformity in 75% of patients. The purpose of this paper is to describe the technique, its indications and complications.

  9. Four year Evaluation of Proximal Resin Infiltration in Adolescents

    PubMed Central

    Kuscu, Ozgur Onder; Hysi, Dorian

    2015-01-01

    Aim Resin infiltration of proximal lesions is a new approach to stopping caries progression. Therefore, the aim of the present study was to evaluate four-year efficacy of proximal infiltrates in adolescents. Materials and methods In ten adolescents, a total of 21 proximal infiltrates (ICON® (DMG, Germany) were applied to initial proximal lesions of permanent incisors and premolars according to the manufacturer’s instruction. The clinical quality of resin infiltration was assessed at 1 week, 1, 2, 3 and 4 years after the treatment and the evaluation of the therapeutic effect was analyzed by radiographs. Results Ten patients were followed up clinically for four years. The majority of the infiltrated lesions were located on permanent incisors. Teeth which were proximally infiltrated did not exhibit dental plaque and gingival bleeding in most cases. At annual recalls, plaque scores remained constant. The gingival status remained steady and no differences in tooth shape and contour were detected. Discoloration was detected in four teeth (19%) in 1st year recall and was constant at annual intervals. The radiographic evaluation of the bitewing radiographs showed no progression in 21 lesions (100%) from baseline to the 4-year recall. Overall oral hygiene of the patients was satisfactory. Conclusion In conclusion, proximal infiltration is an effective prophylactic measure in adolescents.

  10. Four year Evaluation of Proximal Resin Infiltration in Adolescents

    PubMed Central

    Kuscu, Ozgur Onder; Hysi, Dorian

    2015-01-01

    Aim Resin infiltration of proximal lesions is a new approach to stopping caries progression. Therefore, the aim of the present study was to evaluate four-year efficacy of proximal infiltrates in adolescents. Materials and methods In ten adolescents, a total of 21 proximal infiltrates (ICON® (DMG, Germany) were applied to initial proximal lesions of permanent incisors and premolars according to the manufacturer’s instruction. The clinical quality of resin infiltration was assessed at 1 week, 1, 2, 3 and 4 years after the treatment and the evaluation of the therapeutic effect was analyzed by radiographs. Results Ten patients were followed up clinically for four years. The majority of the infiltrated lesions were located on permanent incisors. Teeth which were proximally infiltrated did not exhibit dental plaque and gingival bleeding in most cases. At annual recalls, plaque scores remained constant. The gingival status remained steady and no differences in tooth shape and contour were detected. Discoloration was detected in four teeth (19%) in 1st year recall and was constant at annual intervals. The radiographic evaluation of the bitewing radiographs showed no progression in 21 lesions (100%) from baseline to the 4-year recall. Overall oral hygiene of the patients was satisfactory. Conclusion In conclusion, proximal infiltration is an effective prophylactic measure in adolescents. PMID:27688414

  11. Design and Clinical Application of Proximal Humerus Memory Connector

    NASA Astrophysics Data System (ADS)

    Xu, Shuo-Gui; Zhang, Chun-Cai

    2011-02-01

    Treatment for comminuted proximal humerus fractures and nonunions are a substantial challenge for orthopedic surgeons. Plate and screw fixation does not provide enough stability to allow patients to begin functional exercises early after surgery. Using shape memory material nickel titanium alloy, we designed a new device for treating severe comminuted proximal humerus fractures that accommodates for the anatomical features of the proximal humerus. Twenty-two cases of comminuted fracture, malunion, and nonunion of the proximal humerus were treated with the proximal humeral memory connector (PHMC). No external fixation was needed after the operation and patients began active shoulder exercises an average of 8 days after the operation. Follow-up evaluation (mean 18.5 months) revealed that bone healing with lamellar bone formation occurred an average of 3.6 months after surgery for the fracture cases and 4.5 months after surgery for the nonunion cases. Average shoulder function was 88.5 according to the criteria of Michael Reese. PHMC is an effective new device to treat comminuted proximal humerus fractures and nonunions. The use of this device may reduce the need for shoulder joint arthroplasty.

  12. Psychological responses to the proximity of climate change

    NASA Astrophysics Data System (ADS)

    Brügger, Adrian; Dessai, Suraje; Devine-Wright, Patrick; Morton, Thomas A.; Pidgeon, Nicholas F.

    2015-12-01

    A frequent suggestion to increase individuals' willingness to take action on climate change and to support relevant policies is to highlight its proximal consequences, that is, those that are close in space and time. But previous studies that have tested this proximizing approach have not revealed the expected positive effects on individual action and support for addressing climate change. We present three lines of psychological reasoning that provide compelling arguments as to why highlighting proximal impacts of climate change might not be as effective a way to increase individual mitigation and adaptation efforts as is often assumed. Our contextualization of the proximizing approach within established psychological research suggests that, depending on the particular theoretical perspective one takes on this issue, and on specific individual characteristics suggested by these perspectives, proximizing can bring about the intended positive effects, can have no (visible) effect or can even backfire. Thus, the effects of proximizing are much more complex than is commonly assumed. Revealing this complexity contributes to a refined theoretical understanding of the role that psychological distance plays in the context of climate change and opens up further avenues for future research and for interventions.

  13. 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 α: d=v2sinα/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

  14. Relationship between sodium-dependent phosphate transporter (NaPi-IIc) function and cellular vacuole formation in opossum kidney cells.

    PubMed

    Shiozaki, Yuji; Segawa, Hiroko; Ohnishi, Saori; Ohi, Akiko; Ito, Mikiko; Kaneko, Ichiro; Kido, Shinsuke; Tatsumi, Sawako; Miyamoto, Ken-ichi

    2015-01-01

    NaPi-IIc/SLC34A3 is a sodium-dependent inorganic phosphate (Pi) transporter in the renal proximal tubules and its mutations cause hereditary hypophosphatemic rickets with hypercalciuria (HHRH). In the present study, we created a specific antibody for opossum SLC34A3, NaPi-IIc (oNaPi-IIc), and analyzed its localization and regulation in opossum kidney cells (a tissue culture model of proximal tubular cells). Immunoreactive oNaPi-IIc protein levels increased during the proliferative phase and decreased during differentiation. Moreover, stimulating cell growth upregulated oNaPi-IIc protein levels, whereas suppressing cell proliferation downregulated oNaPi-IIc protein levels. Immunocytochemistry revealed that endogenous and exogenous oNaPi-IIc proteins localized at the protrusion of the plasma membrane, which is a phosphatidylinositol 4,5-bisphosphate (PIP2) rich-membrane, and at the intracellular vacuolar membrane. Exogenous NaPi-IIc also induced cellular vacuoles and localized in the plasma membrane. The ability to form vacuoles is specific to electroneutral NaPi-IIc, and not electrogenic NaPi-IIa or NaPi-IIb. In addition, mutations of NaPi-IIc (S138F and R468W) in HHRH did not cause cellular PIP2-rich vacuoles. In conclusion, our data anticipate that NaPi-IIc may regulate PIP2 production at the plasma membrane and cellular vesicle formation. PMID:26399350

  15. InPhaDel: integrative shotgun and proximity-ligation sequencing to phase deletions with single nucleotide polymorphisms

    PubMed Central

    Patel, Anand; Edge, Peter; Selvaraj, Siddarth; Bansal, Vikas; Bafna, Vineet

    2016-01-01

    Phasing of single nucleotide (SNV), and structural variations into chromosome-wide haplotypes in humans has been challenging, and required either trio sequencing or restricting phasing to population-based haplotypes. Selvaraj et al. demonstrated single individual SNV phasing is possible with proximity ligated (HiC) sequencing. Here, we demonstrate HiC can phase structural variants into phased scaffolds of SNVs. Since HiC data is noisy, and SV calling is challenging, we applied a range of supervised classification techniques, including Support Vector Machines and Random Forest, to phase deletions. Our approach was demonstrated on deletion calls and phasings on the NA12878 human genome. We used three NA12878 chromosomes and simulated chromosomes to train model parameters. The remaining NA12878 chromosomes withheld from training were used to evaluate phasing accuracy. Random Forest had the highest accuracy and correctly phased 86% of the deletions with allele-specific read evidence. Allele-specific read evidence was found for 76% of the deletions. HiC provides significant read evidence for accurately phasing 33% of the deletions. Also, eight of eight top ranked deletions phased by only HiC were validated using long range polymerase chain reaction and Sanger. Thus, deletions from a single individual can be accurately phased using a combination of shotgun and proximity ligation sequencing. InPhaDel software is available at: http://l337x911.github.io/inphadel/. PMID:27105843

  16. Investigating the influences of season and coastal proximity on the elemental composition of harvested rainwater.

    PubMed

    Martin, A R; Coombes, P J; Dunstan, R H

    2010-01-01

    Chemical qualities of harvested rainwater were assessed at two residential study sites on the east coast of Australia in relation to coastal proximity and surrounding land uses over the course of a winter and summer month. Daily rainwater samples were collected from the base outlet and surface levels of stored water for chemical analyses. High resolution inductively coupled plasma-mass spectrometry (ICP-MS) was used to analyse 26 elements in all samples. The summer sampling regime for the industrial coastal Site 1 was dominated by wind gusts originating from the east with a total average elemental load of 25,900+/-17,000 microg/L compared to the significantly lower 10,600+/-3,370 microg/L measured during the winter month, where 84% of wind gust events originated from the west. Data for the inland Site 2, with no proximity to industry, revealed no significant changes in total average loads between the winter (4,870+/-578 microg/L) and summer (4,760+/-2,280 microg/L) months. The most abundant elements found at both sites included Na, K, Mg, and Zn. The rainwater storages at Site 2 fed from a relatively new concrete tiled roof catchment had significantly lower pH and conductivity measurements compared with those at Site 1 with an old galvanised iron roof catchment. It was concluded that seasonal differences in harvested water quality were likely influenced by prevailing wind direction and external influences such as surrounding land uses and proximity to the coast.

  17. Proximal small intestinal mucosal injury. Maintenance of glucose and glucose polymer absorption, attenuation of disaccharide absorption.

    PubMed

    Palacios, M; Madariaga, H; Heitlinger, L; Lee, P C; Lebenthal, E

    1989-03-01

    The effect of chronic intragastric infusion of hypertonic mannitol on small intestinal mucosal structure and function was studied in adult rats. Animals were gavage-fed 20% mannitol (1300 mosm) at a dose of 5 ml/100 g body weight daily for seven days. Control animals were gavage-fed tap water on the same schedule. On day 8, the animals were anesthetized, the duodenum cannulated, and a test sugar (glucose, glucose polymer, lactose, sucrose, or maltose) was infused at a dose of 0.5 g/kg body weight in 2.5 ml distilled water over less than 1 min. Portal vein glucose was measured at 30-min intervals from 0 to 120 min. Mannitol treatment resulted in histologic and biochemical alterations (reduced lactase, sucrase, maltase) limited to the proximal small intestine compared to the control group. The absorption of glucose and glucose polymers was similar in mannitol-treated and control animals. In contrast, digestion and absorption of lactose, sucrose, and maltose was significantly diminished in mannitol-treated animals when compared to controls. No changes in permeability to polyethylene glycol 4000 or Na+-coupled glucose transport were observed in mannitol-treated animals compared to controls. These data suggest that when the intestinal mucosa is exposed to hyperosmolar loads that the digestive capacity for disaccharides is suppressed more than its glucose absorptive capacities. Furthermore, glucose oligomers may be more readily digested and absorbed than disaccharides, in this setting, due, in part, to the proximal injury and less pronounced proximal-distal gradient for glucoamylase than other brush-border carbohydrases.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Induced spectral gap and pairing correlations from superconducting proximity effect

    NASA Astrophysics Data System (ADS)

    Chiu, Ching-Kai; Cole, William S.; Das Sarma, S.

    2016-09-01

    We theoretically consider superconducting proximity effect, using the Bogoliubov-de Gennes (BdG) theory, in heterostructure sandwich-type geometries involving a normal s -wave superconductor and a nonsuperconducting material with the proximity effect being driven by Cooper pairs tunneling from the superconducting slab to the nonsuperconducting slab. Applications of the superconducting proximity effect may rely on an induced spectral gap or induced pairing correlations without any spectral gap. We clarify that in a nonsuperconducting material the induced spectral gap and pairing correlations are independent physical quantities arising from the proximity effect. This is a crucial issue in proposals to create topological superconductivity through the proximity effect. Heterostructures of three-dimensional topological insulator (TI) slabs on conventional s -wave superconductor (SC) substrates provide a platform, with proximity-induced topological superconductivity expected to be observed on the "naked" top surface of a thin TI slab. We theoretically study the induced superconducting gap on this naked surface. In addition, we compare against the induced spectral gap in heterostructures of SC with a normal metal or a semiconductor with strong spin-orbit coupling and a Zeeman splitting potential (another promising platform for topological superconductivity). We find that for any model for the non-SC metal (including metallic TI) the induced spectral gap on the naked surface decays as L-3 as the thickness (L ) of the non-SC slab is increased in contrast to the slower 1 /L decay of the pairing correlations. Our distinction between proximity-induced spectral gap (with its faster spatial decay) and pairing correlation (with its slower spatial decay) has important implications for the currently active search for topological superconductivity and Majorana fermions in various superconducting heterostructures.

  19. Immunological Functions of the Membrane Proximal Region of MHC Class II Molecules

    PubMed Central

    Harton, Jonathan; Jin, Lei; Hahn, Amy; Drake, Jim

    2016-01-01

    Major histocompatibility complex (MHC) class II molecules present exogenously derived antigen peptides to CD4 T cells, driving activation of naïve T cells and supporting CD4-driven immune functions. However, MHC class II molecules are not inert protein pedestals that simply bind and present peptides. These molecules also serve as multi-functional signaling molecules delivering activation, differentiation, or death signals (or a combination of these) to B cells, macrophages, as well as MHC class II-expressing T cells and tumor cells. Although multiple proteins are known to associate with MHC class II, interaction with STING (stimulator of interferon genes) and CD79 is essential for signaling. In addition, alternative transmembrane domain pairing between class II α and β chains influences association with membrane lipid sub-domains, impacting both signaling and antigen presentation. In contrast to the membrane-distal region of the class II molecule responsible for peptide binding and T-cell receptor engagement, the membrane-proximal region (composed of the connecting peptide, transmembrane domain, and cytoplasmic tail) mediates these “non-traditional” class II functions. Here, we review the literature on the function of the membrane-proximal region of the MHC class II molecule and discuss the impact of this aspect of class II immunobiology on immune regulation and human disease. PMID:27006762

  20. Regulatory volume decrease in perfused proximal nephron: evidence for a dumping of cell K+.

    PubMed

    Kirk, K L; DiBona, D R; Schafer, J A

    1987-05-01

    We utilized the microscopic and morphometric procedures described in the preceding paper to examine the role of a swelling-activated dumping of K-salt in the reversal of hyposmotic cell swelling in the perfused proximal nephron. The rate of the regulatory volume decrease that follows cell swelling in dilute solutions was reduced by two maneuvers that attenuate the K+ chemical potential difference across the basolateral membrane; inhibiting the Na+-K+ pump (e.g., with ouabain) and raising the peritubular K+ concentration. The rate of the regulatory volume decrease was also inhibited by peritubular quinine, which blocks K channels and volume regulation for a number of mammalian cells. Additionally, exposure to hyposmotic solutions resulted in a sustained and quinine-sensitive increase in the apparent permeability of the basolateral membrane to K+ salt, which was monitored qualitatively as the rate of cell volume change that was induced by a perturbation in the peritubular K+ concentration. The simplest interpretation of these results is that the reversal of hyposmotic cell swelling in the proximal nephron is referable at least in part to a swelling-activated loss of K-salt and water from the cells. PMID:2437806

  1. 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.

  2. Immunological Functions of the Membrane Proximal Region of MHC Class II Molecules.

    PubMed

    Harton, Jonathan; Jin, Lei; Hahn, Amy; Drake, Jim

    2016-01-01

    Major histocompatibility complex (MHC) class II molecules present exogenously derived antigen peptides to CD4 T cells, driving activation of naïve T cells and supporting CD4-driven immune functions. However, MHC class II molecules are not inert protein pedestals that simply bind and present peptides. These molecules also serve as multi-functional signaling molecules delivering activation, differentiation, or death signals (or a combination of these) to B cells, macrophages, as well as MHC class II-expressing T cells and tumor cells. Although multiple proteins are known to associate with MHC class II, interaction with STING (stimulator of interferon genes) and CD79 is essential for signaling. In addition, alternative transmembrane domain pairing between class II α and β chains influences association with membrane lipid sub-domains, impacting both signaling and antigen presentation. In contrast to the membrane-distal region of the class II molecule responsible for peptide binding and T-cell receptor engagement, the membrane-proximal region (composed of the connecting peptide, transmembrane domain, and cytoplasmic tail) mediates these "non-traditional" class II functions. Here, we review the literature on the function of the membrane-proximal region of the MHC class II molecule and discuss the impact of this aspect of class II immunobiology on immune regulation and human disease. PMID:27006762

  3. Transcriptional regulation of NHE3 and SGLT1 by the circadian clock protein Per1 in proximal tubule cells.

    PubMed

    Solocinski, Kristen; Richards, Jacob; All, Sean; Cheng, Kit-Yan; Khundmiri, Syed J; Gumz, Michelle L

    2015-12-01

    We have previously demonstrated that the circadian clock protein period (Per)1 coordinately regulates multiple genes involved in Na(+) reabsorption in renal collecting duct cells. Consistent with these results, Per1 knockout mice exhibit dramatically lower blood pressure than wild-type mice. The proximal tubule is responsible for a majority of Na(+) reabsorption. Previous work has demonstrated that expression of Na(+)/H(+) exchanger 3 (NHE3) oscillates with a circadian pattern and Na(+)-glucose cotransporter (SGLT)1 has been demonstrated to be a circadian target in the colon, but whether these target genes are regulated by Per1 has not been investigated in the kidney. The goal of the present study was to determine if Per1 regulates the expression of NHE3, SGLT1, and SGLT2 in the kidney. Pharmacological blockade of nuclear Per1 entry resulted in decreased mRNA expression of SGLT1 and NHE3 but not SGLT2 in the renal cortex of mice. Per1 small interfering RNA and pharmacological blockade of Per1 nuclear entry in human proximal tubule HK-2 cells yielded the same results. Examination of heterogeneous nuclear RNA suggested that the effects of Per1 on NHE3 and SGLT1 expression occurred at the level of transcription. Per1 and the circadian protein CLOCK were detected at promoters of NHE3 and SGLT1. Importantly, both membrane and intracellular protein levels of NHE3 and SGLT1 were decreased after blockade of nuclear Per1 entry. This effect was associated with reduced activity of Na(+)-K(+)-ATPase. These data demonstrate a role for Per1 in the transcriptional regulation of NHE3 and SGLT1 in the kidney.

  4. Evidence for a role of claudin 2 as a proximal tubular stress responsive paracellular water channel

    SciTech Connect

    Wilmes, Anja Aschauer, Lydia; Limonciel, Alice; Pfaller, Walter; Jennings, Paul

    2014-09-01

    Claudins are the major proteins of the tight junctions and the composition of claudin subtypes is decisive for the selective permeability of the paracellular route and thus tissue specific function. Their regulation is complex and subject to interference by several factors, including oxidative stress. Here we show that exposure of cultured human proximal tubule cells (RPTEC/TERT1) to the immunosuppressive drug cyclosporine A (CsA) induces an increase in transepithelial electrical resistance (TEER), a decrease in dome formation (on solid growth supports) and a decrease in water transport (on microporous growth supports). In addition, CsA induced a dramatic decrease in the mRNA for the pore forming claudins -2 and -10, and the main subunits of the Na{sup +}/K{sup +} ATPase. Knock down of claudin 2 by shRNA had no discernable effect on TEER or dome formation but severely attenuated apical to basolateral water reabsorption when cultured on microporous filters. Generation of an osmotic gradient in the basolateral compartment rescued water transport in claudin 2 knock down cells. Inhibition of Na{sup +}/K{sup +} ATPase with ouabain prevented dome formation in both cell types. Taken together these results provide strong evidence that dome formation is primarily due to transcellular water transport following a solute osmotic gradient. However, in RPTEC/TERT1 cells cultured on filters under iso-osmotic conditions, water transport is primarily paracellular, most likely due to local increases in osmolarity in the intercellular space. In conclusion, this study provides strong evidence that claudin 2 is involved in paracellular water transport and that claudin 2 expression is sensitive to compound induced cellular stress. - Highlights: • Cyclosporine A increased TEER and decreased water transport in RPTEC/TERT1 cells. • Claudins 2 and 10 were decreased in response to cyclosporine A. • Knock down of claudin 2 inhibited water transport in proximal tubular cells. • We

  5. Osmotic diuresis in a mathematical model of the rat proximal tubule.

    PubMed

    Weinstein, A M

    1986-05-01

    Solute reabsorption in the presence of an osmotic load has been examined in a model of the rat proximal convoluted tubule. The model is a computer simulation of a 0.5-cm segment of tubule comprised of compliant cellular and paracellular compartments, which tracks the luminal profiles of Na, K, Cl, HCO3, phosphate, glucose, and urea. In one series of calculations, the peritubular and initial luminal glucose concentrations are varied from 1.0 to 50 mmol/liter. The resulting proximal reabsorption of glucose increases monotonically to 1.5 nmol X s-1 X cm-2. Sodium reabsorption increases with glucose perfusion concentrations between 1.0 and 10 mmol/liter and then declines with greater glucose loads. Above 10 mmol/liter glucose, there is progressive decline in mean luminal Na concentration so that diffusive paracellular backflux, as well as decreased convective reabsorption, are responsible for the natriuresis. Diuresis per se blunts reabsorption of species requiring the development of lumen-to-bath concentration gradients (i.e., K, Cl, and urea). Diminished bicarbonate reabsorption is also predicted with large glucose loads due to intraepithelial alkalinization. This derives both from cellular depolarization and bicarbonate trapping (interspace closure). It is also observed that when interspace closure occurs, a region of intraepithelial K depletion may be formed, promoting diffusive reabsorption of potassium across the tight junction. Thus a 'middle compartment model' for potassium may provide a means of achieving tubule fluid-to-plasma K ratios less than 1.0, in the absence of specific cellular uptake mechanisms. PMID:3706538

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

    SciTech Connect

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

    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 μm. 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 μm 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.

  7. Proximal femur fractures: the pioneer era of 1818 to 1925.

    PubMed

    Bartonícek, Jan

    2004-02-01

    The foundations of the modern era of the treatment of proximal femur fractures were laid by Cooper who in 1819 published the first therapeutically oriented classification of these fractures. During the following 100 years the clinical diagnostics were further developed; five classifications of proximal femur fractures were formulated including the terminology used until now (peritrochanteric, intertrochanteric), and surgical treatment was started. The first attempt at internal fixation of the proximal femur in the 1850s was by Langenbeck. His patient died of sepsis. The first successful internal fixation of proximal femur fractures was done in 1875 by König. At the beginning of the twentieth century the method of surgical treatment for proximal femur fractures was improved by Lambotte, Delbet, and Putti. However, the time was not ready yet for this method of treatment. Only technologic progress (stainless steel, new technology), the additional development of anesthesia and asepsis, improvement of xray apparatus, and introduction of the traction table created the prerequisites for successful gradation of Smith-Petersen's method from 1925 to 1931, and which a few years later was used worldwide. PMID:15021169

  8. Symmetry-based reciprocity: evolutionary constraints on a proximate mechanism

    PubMed Central

    Campennì, Marco

    2016-01-01

    Background. While the evolution of reciprocal cooperation has attracted an enormous attention, the proximate mechanisms underlying the ability of animals to cooperate reciprocally are comparatively neglected. Symmetry-based reciprocity is a hypothetical proximate mechanism that has been suggested to be widespread among cognitively unsophisticated animals. Methods. We developed two agent-based models of symmetry-based reciprocity (one relying on an arbitrary tag and the other on interindividual proximity) and tested their ability both to reproduce significant emergent features of cooperation in group living animals and to promote the evolution of cooperation. Results. Populations formed by agents adopting symmetry-based reciprocity showed differentiated “social relationships” and a positive correlation between cooperation given and received: two common aspects of animal cooperation. However, when reproduction and selection across multiple generations were added to the models, agents adopting symmetry-based reciprocity were outcompeted by selfish agents that never cooperated. Discussion. In order to evolve, hypothetical proximate mechanisms must be able to stand competition from alternative strategies. While the results of our simulations require confirmation using analytical methods, we provisionally suggest symmetry-based reciprocity is to be abandoned as a possible proximate mechanism underlying the ability of animals to reciprocate cooperative interactions. PMID:26998412

  9. Symmetry-based reciprocity: evolutionary constraints on a proximate mechanism.

    PubMed

    Campennì, Marco; Schino, Gabriele

    2016-01-01

    Background. While the evolution of reciprocal cooperation has attracted an enormous attention, the proximate mechanisms underlying the ability of animals to cooperate reciprocally are comparatively neglected. Symmetry-based reciprocity is a hypothetical proximate mechanism that has been suggested to be widespread among cognitively unsophisticated animals. Methods. We developed two agent-based models of symmetry-based reciprocity (one relying on an arbitrary tag and the other on interindividual proximity) and tested their ability both to reproduce significant emergent features of cooperation in group living animals and to promote the evolution of cooperation. Results. Populations formed by agents adopting symmetry-based reciprocity showed differentiated "social relationships" and a positive correlation between cooperation given and received: two common aspects of animal cooperation. However, when reproduction and selection across multiple generations were added to the models, agents adopting symmetry-based reciprocity were outcompeted by selfish agents that never cooperated. Discussion. In order to evolve, hypothetical proximate mechanisms must be able to stand competition from alternative strategies. While the results of our simulations require confirmation using analytical methods, we provisionally suggest symmetry-based reciprocity is to be abandoned as a possible proximate mechanism underlying the ability of animals to reciprocate cooperative interactions.

  10. Orthopaedic Approaches to Proximal Humeral Fractures Following Trauma

    PubMed Central

    Mafi, Reza; Khan, Wasim; Mafi, Pouya; Hindocha, Sandip

    2014-01-01

    Proximal humeral fractures have been a topic of discussion in medical literature dating back as far as 3rd century BC. Today, these fractures are the most common type of humeral fractures and account for about 5-6% of all fractures in adults with the incidence rising rapidly with age. In broad terms the management of proximal humeral fractures can be divided into two categories: conservative versus surgical intervention. The aim of treatment is to stabilize the fracture, aid better union and reduce pain during the healing process. Failure to achieve this can result in impairment of function, and significantly weaken the muscles inserting onto the proximal humerus. With the rising incidence of proximal humeral fractures, especially among the elderly, the short and long term burden for patients as well as the wider society is increasing. Furthermore, there is a lack of consistency in the definitive treatment and management of displaced fractures. This systematic review of literature compares the surgical treatment of proximal humeral fractures with their conservative management, by evaluating the available randomised controlled trials on this topic. PMID:25408786

  11. Treatment of Hostile Proximal Necks During Endovascular Aneurysm Repair

    PubMed Central

    Navarro, Tulio Pinho; Bernardes, Rodrigo de Castro; Procopio, Ricardo Jayme; Leite, Jose Oyama; Dardik, Alan

    2014-01-01

    Endovascular aneurysm repair (EVAR) is a therapy that continues to evolve rapidly as advances in technology are incorporated into new generations of devices and surgical practice. Although EVAR has emerged as a safe and effective treatment for patients with favorable anatomy, treatment of patients with unfavorable anatomy remains controversial and is still an off-label indication for endovascular treatment with some current stent-grafts. The proximal neck of the aneurysm remains the most hostile anatomic barrier to successful endovascular repair with long-term durability. Open surgery for unfavorable necks is still considered the gold standard treatment in contemporary practice, despite the increased mortality and morbidity attributed to suprarenal cross-clamping, particularly in high-risk patients. Evolving technology may overcome the obstacles preventing endovascular treatment of unfavorable proximal neck anatomy; current approaches include purely endovascular as well as hybrid approaches, and generally include strategies that either extend the length of the short neck, move the proximal neck more proximally, or keep the short neck intact. These approaches include the use of debranching techniques, banding, chimneys, fenestrated and branched devices, filling the sac with endobags, endoanchors, and other novel devices. These newer-generation devices appear to have promising short- and midterm results. However, lack of good evidence of efficacy with long-term results for these newer approaches still precludes wide dissemination of endovascular solutions for the hostile proximal neck. PMID:26798712

  12. Treatment of Hostile Proximal Necks During Endovascular Aneurysm Repair.

    PubMed

    Navarro, Tulio Pinho; Bernardes, Rodrigo de Castro; Procopio, Ricardo Jayme; Leite, Jose Oyama; Dardik, Alan

    2014-02-01

    Endovascular aneurysm repair (EVAR) is a therapy that continues to evolve rapidly as advances in technology are incorporated into new generations of devices and surgical practice. Although EVAR has emerged as a safe and effective treatment for patients with favorable anatomy, treatment of patients with unfavorable anatomy remains controversial and is still an off-label indication for endovascular treatment with some current stent-grafts. The proximal neck of the aneurysm remains the most hostile anatomic barrier to successful endovascular repair with long-term durability. Open surgery for unfavorable necks is still considered the gold standard treatment in contemporary practice, despite the increased mortality and morbidity attributed to suprarenal cross-clamping, particularly in high-risk patients. Evolving technology may overcome the obstacles preventing endovascular treatment of unfavorable proximal neck anatomy; current approaches include purely endovascular as well as hybrid approaches, and generally include strategies that either extend the length of the short neck, move the proximal neck more proximally, or keep the short neck intact. These approaches include the use of debranching techniques, banding, chimneys, fenestrated and branched devices, filling the sac with endobags, endoanchors, and other novel devices. These newer-generation devices appear to have promising short- and midterm results. However, lack of good evidence of efficacy with long-term results for these newer approaches still precludes wide dissemination of endovascular solutions for the hostile proximal neck.

  13. Influence of surround proximity on induction of brown and darkness.

    PubMed

    Buck, Steven L; Shelton, Andrew; Stoehr, Brooke; Hadyanto, Vina; Tang, Miaolu; Morimoto, Takuma; DeLawyer, Tanner

    2016-03-01

    A bright white surround makes a yellow long-wavelength target look both browner and darker. We explored the parallel between these two types of induction by examining their dependence on the proximity of the bright surround to the target at two different time scales with 27 ms and 1 s stimulus durations. We assessed (a) brown induction by adjustment of target luminance to perceptual brown and yellow boundaries and (b) darkness induction by a successive matching procedure. We found that brown induction is a quick process that is robust even for 27 ms stimuli. For darkness induction, there was a strong, spatially localized surround proximity effect for the 27 ms stimuli and much weaker proximity effect for the 1 s stimuli. For brown induction, proximity effects were generally weaker but still showed relatively stronger localized proximity effects for 27 ms stimuli than for 1 s stimuli. For these stimuli, darkness induction predicts the relative pattern but not the magnitudes of brown induction. Both brown and darkness inductions show the operation of quick, spatially localized processes that are apparently superseded by other processes for extended stimulus presentations.

  14. Degradation and transport of AVP by proximal tubule

    SciTech Connect

    Carone, F.A.; Christensen, E.I.; Flouret, G. Univ. of Aarhus )

    1987-12-01

    High-performance liquid chromatography (HPLC) analysis revealed that (3,4,5-{sup 3}H-Phe{sup 3},Arg{sup 8})vasopressin (({sup 3}H)AVP) was not degraded by isolated renal brush-border membranes or by a cortical lysosomal fraction in vitro; however, in the presence of 1 mM reduced glutathione, ({sup 3}H)AVP was degraded by both preparations. Renal cortical homogenates in vitro and luminal peptidases of proximal tubule in vivo degraded ({sup 3}H)AVP and in both instances yielded phenylalanine, hexapeptide AVP 1-6, heptapeptide AVP 1-7, octapeptide AVP 1-8, and two uncharacterized products X and Y. These data suggest that filtered AVP is reduced in the proximal tubule by a reduced glutathione-dependent transhydrogenase and subsequently cleaved to ({sup 3}H)Phe by tubular aminopeptidases. Following microinfusion of ({sup 3}H)AVP into proximal tubules, 15.7% of the label was absorbed. Five and fifteen minutes after infusion of ({sup 3}H)AVP, sequestration of total label in proximal tubules was 4.5 and 2.1%, respectively, and quantitative electron microscope autoradiography revealed accumulation of grains over apical endocytic vacuoles and lysosomes consistent with endocytic uptake and rapid lysosomal degradation of AVP and/or a large metabolite. Thus, enzymatic cleavage of AVP by luminal and lysosomal peptidases in proximal tubules could involve disulfide bond, C-terminal, and N-terminal loci.

  15. Tenofovir renal toxicity targets mitochondria of renal proximal tubules

    PubMed Central

    Kohler, James J; Hosseini, Seyed H; Hoying-Brandt, Amy; Green, Elgin; Johnson, David M; Russ, Rodney; Tran, Dung; Raper, C Michael; Santoianni, Robert; Lewis, William

    2009-01-01

    Tenofovir disoproxil fumarate (TDF) is an analog of adenosine monophosphate that inhibits HIV reverse transcriptase in HIV/AIDS. Despite its therapeutic success, renal tubular side effects are reported. The mechanisms and targets of tenofovir toxicity were determined using ‘2 × 2’ factorial protocols, and HIV transgenic (TG) and wild-type (WT) littermate mice with or without TDF (5 weeks). A parallel study used didanosine (ddI) instead of TDF. At termination, heart, kidney, and liver samples were retrieved. Mitochondrial DNA (mtDNA) abundance, and histo- and ultrastructural pathology were analyzed. Laser-capture microdissection (LCM) was used to isolate renal proximal tubules for molecular analyses. Tenofovir increased mtDNA abundance in TG whole kidneys, but not in their hearts or livers. In contrast, ddI decreased mtDNA abundance in the livers of WTs and TGs, but had no effect on their hearts or kidneys. Histological analyses of kidneys showed no disruption of glomeruli or proximal tubules with TDF or ddI treatments. Ultrastructural changes in renal proximal tubules from TDF-treated TGs included an increased number and irregular shape of mitochondria with sparse fragmented cristae. LCM-captured renal proximal tubules from TGs showed decreased mtDNA abundance with tenofovir. The results indicate that tenofovir targets mitochondrial toxicity on the renal proximal tubule in an AIDS model. PMID:19274046

  16. Symmetry-based reciprocity: evolutionary constraints on a proximate mechanism.

    PubMed

    Campennì, Marco; Schino, Gabriele

    2016-01-01

    Background. While the evolution of reciprocal cooperation has attracted an enormous attention, the proximate mechanisms underlying the ability of animals to cooperate reciprocally are comparatively neglected. Symmetry-based reciprocity is a hypothetical proximate mechanism that has been suggested to be widespread among cognitively unsophisticated animals. Methods. We developed two agent-based models of symmetry-based reciprocity (one relying on an arbitrary tag and the other on interindividual proximity) and tested their ability both to reproduce significant emergent features of cooperation in group living animals and to promote the evolution of cooperation. Results. Populations formed by agents adopting symmetry-based reciprocity showed differentiated "social relationships" and a positive correlation between cooperation given and received: two common aspects of animal cooperation. However, when reproduction and selection across multiple generations were added to the models, agents adopting symmetry-based reciprocity were outcompeted by selfish agents that never cooperated. Discussion. In order to evolve, hypothetical proximate mechanisms must be able to stand competition from alternative strategies. While the results of our simulations require confirmation using analytical methods, we provisionally suggest symmetry-based reciprocity is to be abandoned as a possible proximate mechanism underlying the ability of animals to reciprocate cooperative interactions. PMID:26998412

  17. Role of diacylglycerol in adrenergic-stimulated sup 86 Rb uptake by proximal tubules

    SciTech Connect

    Baines, A.D.; Drangova, R.; Ho, P. )

    1990-05-01

    We used rat proximal tubule fragments purified by Percoll centrifugation to examine the role of diacylglycerol (DAG) in noradrenergic-stimulated Na+ reabsorption. Tubular DAG concentration and ouabain-inhibitable 86Rb uptake increased within 30 s after adding norepinephrine (NE) and remained elevated for at least 5 min. NE (1 microM) increased DAG content 17% and ouabain-inhibitable 86Rb uptake 23%. Cirazoline-stimulated 86Rb uptake was not inhibited by BaCl, quinidine, or bumetanide (1-10 microM) or by the omission of HCO3- or Cl- from the medium, but it was completely inhibited by ouabain and furosemide. Oleoyl-acetyl glycerol, L-alpha-1,2-dioctanoylglycerol, and L-alpha-1,2-dioleoylglycerol (DOG) increased total 86Rb uptake 8-11%. 12-O-tetradecanoylphorbol-13-acetate (TPA) (5 nM) increased uptake by only 4%. Staurosporine at 5 nM inhibited DOG stimulation completely, whereas 50 nM staurosporine was required to inhibit NE stimulation completely. Sphingosine inhibited DOG stimulation by 66% but did not inhibit NE stimulation. Amiloride (1 mM) completely blocked DOG stimulation. Monensin increased 86Rb uptake 31% and completely blocked the DOG effect but reduced the NE effect by only 26% (P = 0.08). In tubules from salt-loaded rats, NE did not increase DAG concentration, but NE-stimulated 86Rb uptake was reduced by only 23% (P = 0.15). Thus DAG released by NE may stimulate Na+ entry through Na(+)-H+ exchange. NE predominantly stimulates Na(+)-K(+)-adenosinetriphosphatase (ATPase) by activating a protein kinase that is insensitive to DAG and TPA and is inhibited by staurosporine but not by sphingosine. NE may also stimulate K+ efflux through a BaCl-insensitive K+ channel that is inhibited by millimolar furosemide.

  18. A Flexible Proximity Sensor Fully Fabricated by Inkjet Printing

    PubMed Central

    Wang, Chin-Tsan; Huang, Kuo-Yi; Lin, David T. W.; Liao, Wei-Chia; Lin, Hua-Wei; Hu, Yuh-Chung

    2010-01-01

    A flexible proximity sensor fully fabricated by inkjet printing is proposed in this paper. The flexible proximity sensor is composed of a ZnO layer sandwiched in between a flexible aluminum sheet and a web-shaped top electrode layer. The flexible aluminum sheet serves as the bottom electrode. The material of the top electrode layer is nano silver. Both the ZnO and top electrode layers are deposited by inkjet printing. The fully inkjet printing process possesses the advantages of direct patterning and low-cost. It does not require photolithography and etching processes since the pattern is directly printed on the flexible aluminum sheet. The prototype demonstrates that the presented flexible sensor is sensitive to the human body. It may be applied to proximity sensing or thermal eradiation sensing. PMID:22399923

  19. Graphical Representation of Proximity Measures for Multidimensional Data

    PubMed Central

    Zand, Martin S.; Wang, Jiong; Hilchey, Shannon

    2015-01-01

    We describe the use of classical and metric multidimensional scaling methods for graphical representation of the proximity between collections of data consisting of cases characterized by multidimensional attributes. These methods can preserve metric differences between cases, while allowing for dimensional reduction and projection to two or three dimensions ideal for data exploration. We demonstrate these methods with three datasets for: (i) the immunological similarity of influenza proteins measured by a multidimensional assay; (ii) influenza protein sequence similarity; and (iii) reconstruction of airport-relative locations from paired proximity measurements. These examples highlight the use of proximity matrices, eigenvalues, eigenvectors, and linear and nonlinear mappings using numerical minimization methods. Some considerations and caveats for each method are also discussed, and compact Mathematica programs are provided. PMID:26692757

  20. Common relationships among proximate composition components in fishes

    USGS Publications Warehouse

    Hartman, K.J.; Margraf, F.J.

    2008-01-01

    Relationships between the various body proximate components and dry matter content were examined for five species of fishes, representing anadromous, marine and freshwater species: chum salmon Oncorhynchus keta, Chinook salmon Oncorhynchus tshawytscha, brook trout Salvelinus fontinalis, bluefish Pomatomus saltatrix and striped bass Morone saxatilis. The dry matter content or per cent dry mass of these fishes can be used to reliably predict the per cent composition of the other components. Therefore, with validation it is possible to estimate fat, protein and ash content of fishes from per cent dry mass information, reducing the need for costly and time-consuming laboratory proximate analysis. This approach coupled with new methods of non-lethal estimation of per cent dry mass, such as from bioelectrical impedance analysis, can provide non-destructive measurements of proximate composition of fishes. ?? 2008 The Authors.

  1. The thermometer of social relations: mapping social proximity on temperature.

    PubMed

    Ijzerman, Hans; Semin, Gün R

    2009-10-01

    "Holding warm feelings toward someone" and "giving someone the cold shoulder" indicate different levels of social proximity. In this article, we show effects of temperature that go beyond these metaphors people live by. In three experiments, warmer conditions, compared with colder conditions, induced (a) greater social proximity, (b) use of more concrete language, and (c) a more relational focus. Different temperature conditions were created by either handing participants warm or cold beverages (Experiment 1) or placing them in comfortable warm or cold ambient conditions (Experiments 2 and 3). These studies corroborate recent findings in the field of grounded cognition revealing that concrete experiences ground abstract concepts with which they are coexperienced. Our studies show a systemic interdependence among language, perception, and social proximity: Environmentally induced conditions shape not only language use, but also the perception and construal of social relationships.

  2. Methodology for proximal wear evaluation in posterior resin composites.

    PubMed

    Ziemiecki, T L; Wendt, S L; Leinfelder, K F

    1992-08-01

    The purpose of this study was to utilize a methodology to measure proximal wear of posterior resin composites with respect to time. A group of 10 teeth (5 premolars and 5 molars) were restored with P-30, a posterior resin composite restorative. At placement the proximal contacts were judged to be closed visually, and with unwaxed dental floss. The patients were then recalled at intervals of 6, 12, and 36 months for indirect wear evaluations. Resin composite transfer copings were made and indexed on baseline models. A zoom stereomicroscope, at 20 microns resolution, was used to determine proximal wear. For the posterior restorative material the premolar and molar teeth wore at the same rate. The amount of wear was statistically greater for premolar teeth at 6 and 12-month evaluation periods than molar teeth. At 36 months, there was no statistical difference in wear between premolar and molar teeth.

  3. Pyrocarbon proximal interphalangeal joint arthroplasty: outcomes of a cohort study.

    PubMed

    McGuire, D T; White, C D; Carter, S L; Solomons, M W

    2012-07-01

    Pyrocarbon arthroplasty of the proximal interphalangeal joint is a relatively new concept. Early studies have been encouraging, reporting improved pain and function, but a largely unchanged arc of motion. Subsidence of the implant is common, but how it relates to outcome has not been analyzed. This study was performed to review the results of 57 pyrocarbon proximal interphalangeal implanted joints. Results showed a statistically significant increase in the arc of motion, excellent pain relief, and improved function. Subsidence was observed on radiographs in 40% of joints, but no correlation was found compared with arc of motion or function. The incidence of complications is fairly high and usually related to the peri-articular soft tissues, but they are usually minor and do not require further treatment. From this review, we can recommend the use of this implant for treatment of arthritis of the proximal interphalangeal joint.

  4. The thermometer of social relations: mapping social proximity on temperature.

    PubMed

    Ijzerman, Hans; Semin, Gün R

    2009-10-01

    "Holding warm feelings toward someone" and "giving someone the cold shoulder" indicate different levels of social proximity. In this article, we show effects of temperature that go beyond these metaphors people live by. In three experiments, warmer conditions, compared with colder conditions, induced (a) greater social proximity, (b) use of more concrete language, and (c) a more relational focus. Different temperature conditions were created by either handing participants warm or cold beverages (Experiment 1) or placing them in comfortable warm or cold ambient conditions (Experiments 2 and 3). These studies corroborate recent findings in the field of grounded cognition revealing that concrete experiences ground abstract concepts with which they are coexperienced. Our studies show a systemic interdependence among language, perception, and social proximity: Environmentally induced conditions shape not only language use, but also the perception and construal of social relationships. PMID:19732385

  5. High-throughput determination of RNA structure by proximity ligation.

    PubMed

    Ramani, Vijay; Qiu, Ruolan; Shendure, Jay

    2015-09-01

    We present an unbiased method to globally resolve RNA structures through pairwise contact measurements between interacting regions. RNA proximity ligation (RPL) uses proximity ligation of native RNA followed by deep sequencing to yield chimeric reads with ligation junctions in the vicinity of structurally proximate bases. We apply RPL in both baker's yeast (Saccharomyces cerevisiae) and human cells and generate contact probability maps for ribosomal and other abundant RNAs, including yeast snoRNAs, the RNA subunit of the signal recognition particle and the yeast U2 spliceosomal RNA homolog. RPL measurements correlate with established secondary structures for these RNA molecules, including stem-loop structures and long-range pseudoknots. We anticipate that RPL will complement the current repertoire of computational and experimental approaches in enabling the high-throughput determination of secondary and tertiary RNA structures. PMID:26237516

  6. Bringing proximate neighbours into the study of US residential segregation.

    PubMed

    Friedman, Samantha

    2011-01-01

    The race and ethnicity of neighbours are thought to be critical in shaping household mobility underlying residential segregation. However, studies on this topic have used data at the census-tract level of analysis rather than at the proximate-neighbour level. Using a non-publicly available version of the neighbour-cluster sample within the American Housing Survey, this study incorporates data on the race, ethnicity and socioeconomic characteristics of the proximate neighbours of White, Black and Latino households and examines their impact on household residential satisfaction, out- and in-mobility. Results indicate that proximate-neighbour race and ethnicity matter in influencing endpoints of the mobility process and do not necessarily parallel those at the census-tract level. Implications of these findings are discussed as they relate to the study of residential segregation.

  7. Accelerated reabsorption in the proximal tubule produced by volume depletion.

    PubMed

    Weiner, M W; Weinman, E J; Kashgarian, M; Hayslett, J P

    1971-07-01

    The renal response to chronic depletion of extracellular volume was examined using the techniques of micropuncture. Depletion of salt and water was produced by administration of furosemide to rats maintained on a sodium-free diet. There was a marked fall in body weight, plasma volume, and glomerular filtration rate. The intrinsic reabsorptive capacity of the proximal tubule, measured by the split-droplet technique, was greatly enhanced. The acceleration of proximal fluid reabsorption could not be accounted for by changes in filtration rate, tubular geometry, or aldosterone secretion. The half-time of droplet reabsorption in the distal tubule was not altered by sodium depletion. An increase in the reabsorption of fluid in the proximal tubule, as demonstrated directly in the present experiments, provides an explanation for a variety of clinical phenomena associated with volume depletion.

  8. Proximal arm kinematics affect grip force-load force coordination.

    PubMed

    Vermillion, Billy C; Lum, Peter S; Lee, Sang Wook

    2015-10-01

    During object manipulation, grip force is coordinated with load force, which is primarily determined by object kinematics. Proximal arm kinematics may affect grip force control, as proximal segment motion could affect control of distal hand muscles via biomechanical and/or neural pathways. The aim of this study was to investigate the impact of proximal kinematics on grip force modulation during object manipulation. Fifteen subjects performed three vertical lifting tasks that involved distinct proximal kinematics (elbow/shoulder), but resulted in similar end-point (hand) trajectories. While temporal coordination of grip and load forces remained similar across the tasks, proximal kinematics significantly affected the grip force-to-load force ratio (P = 0.042), intrinsic finger muscle activation (P = 0.045), and flexor-extensor ratio (P < 0.001). Biomechanical coupling between extrinsic hand muscles and the elbow joint cannot fully explain the observed changes, as task-related changes in intrinsic hand muscle activation were greater than in extrinsic hand muscles. Rather, between-task variation in grip force (highest during task 3) appears to contrast to that in shoulder joint velocity/acceleration (lowest during task 3). These results suggest that complex neural coupling between the distal and proximal upper extremity musculature may affect grip force control during movements, also indicated by task-related changes in intermuscular coherence of muscle pairs, including intrinsic finger muscles. Furthermore, examination of the fingertip force showed that the human motor system may attempt to reduce variability in task-relevant motor output (grip force-to-load force ratio), while allowing larger fluctuations in output less relevant to task goal (shear force-to-grip force ratio). PMID:26289460

  9. Proximal arm kinematics affect grip force-load force coordination

    PubMed Central

    Vermillion, Billy C.; Lum, Peter S.

    2015-01-01

    During object manipulation, grip force is coordinated with load force, which is primarily determined by object kinematics. Proximal arm kinematics may affect grip force control, as proximal segment motion could affect control of distal hand muscles via biomechanical and/or neural pathways. The aim of this study was to investigate the impact of proximal kinematics on grip force modulation during object manipulation. Fifteen subjects performed three vertical lifting tasks that involved distinct proximal kinematics (elbow/shoulder), but resulted in similar end-point (hand) trajectories. While temporal coordination of grip and load forces remained similar across the tasks, proximal kinematics significantly affected the grip force-to-load force ratio (P = 0.042), intrinsic finger muscle activation (P = 0.045), and flexor-extensor ratio (P < 0.001). Biomechanical coupling between extrinsic hand muscles and the elbow joint cannot fully explain the observed changes, as task-related changes in intrinsic hand muscle activation were greater than in extrinsic hand muscles. Rather, between-task variation in grip force (highest during task 3) appears to contrast to that in shoulder joint velocity/acceleration (lowest during task 3). These results suggest that complex neural coupling between the distal and proximal upper extremity musculature may affect grip force control during movements, also indicated by task-related changes in intermuscular coherence of muscle pairs, including intrinsic finger muscles. Furthermore, examination of the fingertip force showed that the human motor system may attempt to reduce variability in task-relevant motor output (grip force-to-load force ratio), while allowing larger fluctuations in output less relevant to task goal (shear force-to-grip force ratio). PMID:26289460

  10. Glomerulotubular balance in a mathematical model of the proximal nephron.

    PubMed

    Weinstein, A M

    1990-03-01

    A nonelectrolyte model of proximal tubule epithelium has been extended by the inclusion of a compliant tight junction. Here "compliance" signifies that both the junctional salt and water permeability increase and the salt reflection coefficient decreases in response to small pressure differences from lateral interspace to tubule lumen. In previous models of rat proximal tubule, there has been virtually no sensitivity of isotonic salt transport to changes in peritubular oncotic force. With the inclusion of junctional compliance, decreases in peritubular protein can open the junction and produce a secretory salt flux. Thus the model can represent the "backflux hypothesis," as it was originally put forth (J. E. Lewy and E. E. Windhager, Am. J. Physiol. 214: 943-954, 1968). Additional calculations, simulating a tight junction with negligible water permeability, reveal that the quantitative impact of peritubular protein can be realized whether or not there is substantial junctional water flux. The epithelial model of proximal tubule has also been incorporated into a model of the proximal nephron, complete with glomerulus, peritubular capillary, and interstitium. The interstitial compartment is well mixed and interstitial pressure and osmolality are determined iteratively to achieve balance between tubule reabsorption and capillary uptake. For this model, two domains of operation are identified. When interstitial pressures are low, junctions are closed, and filtration fraction has no effect on proximal reabsorption. When interstitial pressures are relatively elevated, epithelial junctions are open, and proximal salt reabsorption changes in proportion to changes in filtration fraction. In neither domain, however, does the model tubule augment salt flux with isolated increases in luminal flow rate (at constant filtration fraction). The absence of a separate effect of tubule fluid flow on salt transport precludes perfect glomerulotubular balance.

  11. Proximal femoral reconstruction with a constrained acetabulum in oncologic patients.

    PubMed

    Jawad, Muhammad Umar; Brien, Earl W

    2014-02-01

    Metallic endoprostheses are used for oncological reconstruction around the proximal femur and hip joint. Common modes of failure with hemiarthroplasty or standard hip arthroplasty after proximal femoral replacement include dislocation, late hip pain, and infection. The authors reviewed hospital records to identify patients undergoing constrained tripolar hip arthroplasty for oncological reasons between 2002 and 2012. Inclusion criterion was at least 12-cm proximal femoral resection, including patients with total femur reconstruction. A total of 33 patients were reviewed. Information regarding demographics, length of follow-up, treatment characteristics, and patient outcomes was extracted. Average follow-up for all patients was 912.33 days (30.4 months). Average follow-up was 1396.1 days for living patients and 428.6 days for deceased patients. Average estimated blood loss was 462.12 cc: an average of 1080 cc for patients undergoing total femoral resection and replacement and 315.8 cc for patients undergoing proximal femoral resection and replacement. Average operative time was 137.7 minutes: an average of 205 minutes for patients undergoing total femoral resection and replacement and 119.1 minutes for patients undergoing proximal femoral resection and replacement. Average Musculoskeletal Tumor Society score was 21.7. There were no dislocations in the cohort. A constrained tripolar device can be safely used for oncological proximal femoral reconstructions while minimizing the risk of dislocation. Positioning of the acetabular implant in neutral anatomic version in conjunction with a neutral-placed femoral component provides the greatest range of motion, reduction of liner impingement, and improved hip stability.

  12. Proximal aortic dissection (dissecting aortic aneurysm) in a mature ostrich.

    PubMed

    Ferreras, M C; González, J; Pérez, V; Reyes, L E; Gómez, N; Pérez, C; Corpa, J M; García-Marín, J F

    2001-01-01

    The gross and histopathologic lesions observed in a case of spontaneous proximal aortic dissection (dissecting aortic aneurysm) in a mature ostrich are reported. At necropsy, a dissecting intramural hematoma was seen in the proximal aorta, extended about 12 cm distally from the aortic valves. Histopathologic changes in aortic dissection included fragmentation and disruption of elastic laminae, presence of cystic extracellular spaces, and pooling of ground substance in the tunica media. Hepatic copper levels were measured, and the low concentration found suggested that a copper deficiency together with other risk factors such as the elevation of blood pressure may have been implicated in the development of the aortic dissection seen in this ostrich.

  13. Proximal Periprosthetic Femur Fractures: Strategies for Internal Fixation.

    PubMed

    Moloney, Gele B; Toro, Jose B; Helfet, David L; Wellman, David S

    2016-01-01

    As the number of patients living with total hip arthroplasty continues to rise, there will be an increase in periprosthetic fractures requiring surgical treatment. Treatment of periprosthetic femur fractures below a well-fixed hip arthroplasty stem presents a unique set of challenges. A review of the existing literature on surgical technique, including plate selection and configuration, proximal fixation options, and use of allograft, can serve to guide treatment of these challenging injuries. While not conclusive, the literature supports using soft tissue preserving techniques, bicortical proximal fixation, and fixation spanning the length of the femur. PMID:27327912

  14. Metatarsal shaft fractures and fractures of the proximal fifth metatarsal.

    PubMed

    Fetzer, Gary B; Wright, Rick W

    2006-01-01

    Metatarsal fractures represent a relatively common injury, especially in athletes. The pertinent anatomy, evaluation, diagnosis, classification, and treatment of acute and chronic (stress) metatarsal shaft fractures are discussed. Fractures of the proximal fifth metatarsal, which are unique and important injuries, are also discussed. Treatment remains relatively straightforward for the traumatic metatarsal injury, whereas traditional stress fractures typically heal with decreased activity. The problematic proximal fifth metatarsal fracture (Jones fracture) frequently requires surgical intervention in patients who want to avoid non-weight-bearing cast immobilization. The authors' current treatment for this fracture includes the option of intramedullary fixation versus cast immobilization.

  15. Ectrodactyly and proximal/intermediate interstitial deletion 7q

    SciTech Connect

    McElveen, C.; Carvajal, M.V.; Moscatello, D.

    1995-03-13

    We report on an individual with severe mental retardation, seizures, microcephaly, unusual face, scoliosis, and cleft feet and cleft right hand. The chromosomal study showed a proximal interstitial deletion 7q (q11.23q22). From our review of the literature, 11 patients have been reported with ectrodactyly (split hand/split foot malformation) and proximal/intermediate interstitial deletions or rearrangements of 7q. The critical segment for ectrodactyly seems to be located between 7q21.2 and 7q22.1. This malformation is present in 41% of the patients whose deletion involves the critical segment. 37 refs., 3 figs., 1 tab.

  16. Double-driven shield capacitive type proximity sensor

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    1993-01-01

    A capacity type proximity sensor comprised of a capacitance type sensor, a capacitance type reference, and two independent and mutually opposing driven shields respectively adjacent to the sensor and reference and which are coupled in an electrical bridge circuit configuration and driven by a single frequency crystal controlled oscillator is presented. The bridge circuit additionally includes a pair of fixed electrical impedance elements which form adjacent arms of the bridge and which comprise either a pair of precision resistances or capacitors. Detection of bridge unbalance provides an indication of the mutual proximity between an object and the sensor. Drift compensation is also utilized to improve performance and thus increase sensor range and sensitivity.

  17. 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].

  18. ACUTE ISOLATED ANTEROLATERAL DISLOCATION OF THE PROXIMAL TIBIOFIBULAR JOINT.

    PubMed

    Almeida Silvares, Paulo Roberto de; Fernandes Guerreiro, Joao Paulo; Müller, Sergio Swain; Pereira, Ricardo Violante; Vannini, Rodrigo

    2010-01-01

    Isolated traumatic dislocation of the proximal tibiofibular joint is rare. This injury may go unrecognized or be misdiagnosed at the initial presentation. Lack of clinical suspicion can cause diagnostic problems. The diagnosis requires an accurate history of the mechanism and symptoms of the injury, and adequate clinical and radiographic evaluation of both knees. Unrecognized cases are a source of chronic abnormalities. The treatment consists of closed reduction and immobilization or, in non-reducible or unstable cases, open reduction with temporary internal fixation. A rare case of isolated proximal tibiofibular dislocation in a basketball player is reported to illustrate this injury.

  19. 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

  20. Investigation of sodium distribution in phosphate glasses using spin-echo {sup 23}Na NMR

    SciTech Connect

    Alam, T.M.; McLaughlin, J.; Click, C.C.; Conzone, S.; Brow, R.K.; Boyle, T.J.; Zwanziger, J.W.

    2000-02-24

    The spatial arrangements of sodium cations for a series of sodium phosphate glasses, xNa{sub 2}O{sm{underscore}bullet}(100{minus}x)P{sub 2}O{sub 5} (x {le} 55), were investigated using {sup 23}Na spin-echo NMR spectroscopy. The spin-echo decay rate is a function of the Na-Na homonuclear dipolar coupling, and is related to the spatial proximity of neighboring Na nuclei. The spin-echo decay rate in these sodium phosphate glasses increases nonlinearly with higher sodium number density, and thus provides a measure of the Na-Na extended range order. The results of these {sup 23}Na NMR experiments are discussed within the context of several structural models, including a decimated crystal lattice model, cubic dilation lattice model, a hard sphere (HS) random distribution model, and a pairwise cluster hard sphere model. While the experimental {sup 23}Na spin-echo M{sub 2} are described adequately by both the decimated lattice and the random HS models, it is demonstrated that the slight nonlinear behavior of M{sub 2} as a function of sodium number density is more correctly described by the random distribution in the HS model. At low sodium number densities the experimental M{sub 2} is inconsistent with models incorporating Na-Na clustering. The ability to distinguish between Na-Na clusters and nonclustered distributions becomes more difficult at higher sodium concentrations.

  1. Investigation of Sodium Distribution in Phosphate Glasses Using Spin-Echo {sup 23}Na NMR

    SciTech Connect

    ALAM, TODD M.; BOYLE, TIMOTHY J.; BROW, RICHARD K.; CLICK, CAROL C.; CONZONE, SAM; McLAUGHLIN, JAY; ZWANZIGER, JOE

    1999-09-16

    The spatial arrangement of sodium cations for a series of sodium phosphate glasses, xNa{sub 2}O(100-x)P{sub 2}O{sub 5} (x<55), were investigated using {sup 23}Na spin-echo NMR spectroscopy. The spin-echo decay rate is a function of the Na-Na homonuclear dipolar coupling and is related to the spatial proximity of neighboring Na nuclei. The spin-echo decay rate in these sodium phosphate glasses increases non-linearly with higher sodium number density, and thus provides a measure of the Na-Na extended range order. The results of these {sup 23}Na NMR experiments are discussed within the context of several structural models, including a decimated crystal lattice model, cubic dilation lattice model, a hard sphere (HS) random distribution model and a pair-wise cluster hard sphere model. While the experimental {sup 23}Na spin-echo M{sub 2} are described adequately by both the decimated lattice and the random HS model, it is demonstrated that the slight non-linear behavior of M{sub 2} as a function of sodium number density is more correctly described by the random distribution in the HS model. At low sodium number densities the experimental M{sub 2} is inconsistent with models incorporating Na-Na clustering. The ability to distinguish between Na-Na clusters and non-clustered distributions becomes more difficult at higher sodium concentrations.

  2. Proximal Femoral Nail Antirotation Versus Reverse Less Invasive Stabilization System-distal Femur for Treating Proximal Femoral Fractures

    PubMed Central

    Jiang, Xuan; Wang, Ying; Ma, XinLong; Ma, JianXiong; Wang, Chen; Zhang, ChengBao; Han, Zhe; Sun, Lei; Lu, Bin

    2016-01-01

    Abstract The aim of this study was to compare the effectiveness and safety of 2 surgical techniques that are used to treat proximal femoral fractures. A systematic literature search (up to December 2014) was conducted in Medline, Embase, PubMed, and The Cochrane Central Register of Controlled Trials to screen for studies comparing proximal femoral nail antirotation (PFNA) with less invasive stabilization system–distal femur (LISS-DF) for proximal femoral fractures. Two authors independently assessed the methodological quality of the included studies and extracted data. Surgical information and postoperative outcomes were analyzed. A total of 7 studies with 361 patients who satisfied the eligibility criteria included 3 randomized controlled trials and 4 case-controlled trials associated with PFNA versus LISS in treating proximal femoral fractures. Our results demonstrated that there was a significant reduction in hospital stay and time to weight-bearing ambulation and bone healing for PFNA compared with LISS (odds ratio [OR] −1.48, 95% confidence interval [CI] −2.92 to −0.05; OR −7.08, 95% CI −8.32 to −5.84; OR −2.71, 95% CI −4.76 to 0.67). No statistically significant difference was observed between the 2 groups for operative time, blood loss volume, Harris hip score, and incidence of complications. Based on the results of this analysis, we inferred that PFNA is safer and more effective than reverse LISS-DF in patients undergoing osteosynthesis for proximal femoral fractures, and that PFNA is associated with reduced hospital stays and reduced time to weight-bearing ambulation and bone healing. Nonetheless, in certain cases in which PFNA is not suitable due to abnormal structure of the proximal femur or particularly unstable fractures, the LISS plate technique could be a useful alternative. PMID:27057840

  3. Proximal femoral diaphyseal cross-sectional geometry in Orrorin tugenensis.

    PubMed

    Bleuze, M

    2012-06-01

    Functional adaptations in femora attributed to Orrorin tugenensis provide a unique opportunity to examine locomotor behavior very early in the hominin lineage. This study examines relative cortical thickness, cortical area (CA) relative to the polar moment of area (J), and J relative to femoral head superoinferior diameter (FHD) in the proximal femur of O. tugenensis (BAR 1002'00 and BAR 1003'00), and compares patterns in this early hominin with those in a sample of modern humans (N=31), Plio-Pleistocene fossil hominins (N=8), Pan troglodytes troglodytes (N=13), and Pan paniscus (N=3). Relative cortical thickness and CA relative to J in the proximal femur of O. tugenensis are comparable to patterns generally found in other fossil hominins. Proximal femoral diaphyseal J relative to FHD in BAR 1002'00 is similar to patterns found in fossil hominins typically attributed to a non-Homo genus (i.e. SK 82, SK 97, and KNM-ER 738). Cross-sectional geometric patterns in the proximal femur of Orrorin are not unlike those generally found in australopithecines and fossil Homo. While the results of this study cannot confirm unequivocally that Orrorin was an obligate biped, a mode of locomotion comparable to that proposed for australopithecines cannot be ruled out. PMID:22609080

  4. 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.

  5. 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.…

  6. 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…

  7. 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…

  8. Three-part inventions: intracellular signaling and induced proximity.

    PubMed

    Crabtree, G R; Schreiber, S L

    1996-11-01

    Everyone has had the experience of stoking a fire; putting the logs close together causes flames to appear from previously dying embers. In a similar way, mere proximity might mediate qualitative biological responses. We discuss natural molecules that appear to have arisen to bring two proteins together and illustrate how this simple mechanism can be used to control a wide variety of biological processes.

  9. Proximity to coast is linked to climate change belief.

    PubMed

    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.

  10. 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.

  11. Innervation of the renal proximal convoluted tubule of the rat

    SciTech Connect

    Barajas, L.; Powers, K. )

    1989-12-01

    Experimental data suggest the proximal tubule as a major site of neurogenic influence on tubular function. The functional and anatomical axial heterogeneity of the proximal tubule prompted this study of the distribution of innervation sites along the early, mid, and late proximal convoluted tubule (PCT) of the rat. Serial section autoradiograms, with tritiated norepinephrine serving as a marker for monoaminergic nerves, were used in this study. Freehand clay models and graphic reconstructions of proximal tubules permitted a rough estimation of the location of the innervation sites along the PCT. In the subcapsular nephrons, the early PCT (first third) was devoid of innervation sites with most of the innervation occurring in the mid (middle third) and in the late (last third) PCT. Innervation sites were found in the early PCT in nephrons located deeper in the cortex. In juxtamedullary nephrons, innervation sites could be observed on the PCT as it left the glomerulus. This gradient of PCT innervation can be explained by the different tubulovascular relationships of nephrons at different levels of the cortex. The absence of innervation sites in the early PCT of subcapsular nephrons suggests that any influence of the renal nerves on the early PCT might be due to an effect of neurotransmitter released from renal nerves reaching the early PCT via the interstitium and/or capillaries.

  12. Conservative Treatment for Bilateral Displaced Proximal Humerus Head Fracture.

    PubMed

    Rodriguez-Corlay, Ruy E; Velutini-Becker, Ricardo; Aguilar-Alcalá, Luis D

    2016-01-01

    Proximal humerus fracture represents five to eight percent of all fractures and is twice as common in women than in men. Most cases of displaced fracture of the proximal humerus are treated surgically; it is probable that more cases are preferred to be treated surgically greater than required. The optimal treatment for these fractures remains controversial, but physicians have a tendency to treat via open reduction and fixation with angular locking plates or glenohumeral arthroplasty.  We present a case of a 71-year-old woman with bilateral displaced proximal humeral fracture. Conservative treatment was initiated with two hanging casts, achieving radiological reduction on week one. After two additional weeks of casting, treatment continued with radiologic control and home physical therapy, ultimately an excellent functional outcome and adequate radiological reduction was obtained.    Even in bilaterally displaced proximal humerus fractures, conservative treatment can be an efficient option, reducing complications, reaching adequate functional results and acceptable radiographic reduction.​. PMID:27489750

  13. 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…

  14. Technique for temperature compensation of eddy-current proximity probes

    NASA Technical Reports Server (NTRS)

    Masters, Robert M.

    1989-01-01

    Eddy-current proximity probes are used in turbomachinery evaluation testing and operation to measure distances, primarily vibration, deflection, or displacment of shafts, bearings and seals. Measurements of steady-state conditions made with standard eddy-current proximity probes are susceptible to error caused by temperature variations during normal operation of the component under investigation. Errors resulting from temperature effects for the specific probes used in this study were approximately 1.016 x 10 to the -3 mm/deg C over the temperature range of -252 to 100 C. This report examines temperature caused changes on the eddy-current proximity probe measurement system, establishes their origin, and discusses what may be done to minimize their effect on the output signal. In addition, recommendations are made for the installation and operation of the electronic components associated with an eddy-current proximity probe. Several techniques are described that provide active on-line error compensation for over 95 percent of the temperature effects.

  15. 75 FR 33198 - Co-Location/Proximity Hosting Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-11

    ...; ] COMMODITY FUTURES TRADING COMMISSION 17 CFR Parts 36, 37, and 38 Co-Location/Proximity Hosting Services AGENCY: Commodity Futures Trading Commission. ACTION: Proposed rule. SUMMARY: The Commodity Futures... third-parties to carry out their self-regulatory obligations and other obligations under the...

  16. Performance characteristics of proximity focused ultraviolet image converters

    NASA Technical Reports Server (NTRS)

    Williams, J. T.; Feibelman, W. A.

    1973-01-01

    Performance characteristics of Bendix type BX 8025-4522 proximity focused image tubes for ultraviolet to visible light conversion are presented. Quantum efficiency, resolution, background, geometric distortion, and environmental test results are discussed. The converters use magnesium fluoride input windows with Cs - Te photocathodes, and P-11 phosphors on fiber optic output windows.

  17. Performance characteristics of proximity focused ultraviolet image converters

    NASA Technical Reports Server (NTRS)

    Williams, J. T.; Feibelman, W. A.

    1973-01-01

    Performance characteristics of Bendix type BX 8025-4522 proximity focused image tubes for UV to visible light conversion are presented. Quantum efficiency, resolution, background, geometric distortion, and environmental test results are discussed. The converters use magnesium fluoride input windows with Cs-Te photocathodes and P-11 phosphors on fiber optic output windows.

  18. 75 FR 5009 - Proximity Detection Systems for Underground Mines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-01

    ... operators at mine sites from 2002 to 2006. The National Institute for Occupational Safety and Health (NIOSH... Safety and Health Administration 30 CFR Parts 57 and 75 RIN 1219-AB65 Proximity Detection Systems for Underground Mines AGENCY: Mine Safety and Health Administration, Labor. ACTION: Request for...

  19. Proximal femoral diaphyseal cross-sectional geometry in Orrorin tugenensis.

    PubMed

    Bleuze, M

    2012-06-01

    Functional adaptations in femora attributed to Orrorin tugenensis provide a unique opportunity to examine locomotor behavior very early in the hominin lineage. This study examines relative cortical thickness, cortical area (CA) relative to the polar moment of area (J), and J relative to femoral head superoinferior diameter (FHD) in the proximal femur of O. tugenensis (BAR 1002'00 and BAR 1003'00), and compares patterns in this early hominin with those in a sample of modern humans (N=31), Plio-Pleistocene fossil hominins (N=8), Pan troglodytes troglodytes (N=13), and Pan paniscus (N=3). Relative cortical thickness and CA relative to J in the proximal femur of O. tugenensis are comparable to patterns generally found in other fossil hominins. Proximal femoral diaphyseal J relative to FHD in BAR 1002'00 is similar to patterns found in fossil hominins typically attributed to a non-Homo genus (i.e. SK 82, SK 97, and KNM-ER 738). Cross-sectional geometric patterns in the proximal femur of Orrorin are not unlike those generally found in australopithecines and fossil Homo. While the results of this study cannot confirm unequivocally that Orrorin was an obligate biped, a mode of locomotion comparable to that proposed for australopithecines cannot be ruled out.

  20. 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.

  1. Proximity Effect at Graphene - High Tc Superconductor Junctions

    NASA Astrophysics Data System (ADS)

    Wang, Da; Shih, En-Min; Arefe, Ghidewon; Kim, Youngduck; Edelberg, Drew; Andrade, Erick; Wang, Dennis; Hone, James; Dean, Cory; Pasupathy, Abhay; Department of Physics, Columbia University, New York, NY 10027, USA Collaboration

    The proximity effect is a well-known mesoscopic phenomenon where Cooper pairs from a superconductor (S) enter into a normal metal (N) that is well coupled to it. Since graphene was discovered a decade ago, the proximity effect at superconductor-graphene junctions has been extensively studied and interesting phenomena such as specular Andreev reflection and ballistic transport at graphene Josephson junctions have been observed. However, superconductors used in these experiments to date are of conventional low Tc, such as aluminum(Tc=1.2K), NbSe2(Tc=7K), and MoRe(Tc=8K). Understanding how the proximity effect works between high-Tc superconductors (pnictides and cuprates) and the Dirac Fermions of graphene remains largely unexplored. The chief technical challenge here is to create high-quality junctions between high-Tc superconductors and graphene. In this work, we will introduce a home-made setup that allows us to exfoliate, transfer and encapsulate superconductor-graphene junctions in a well controlled inert atmosphere. Transport measurements of the proximity effect at graphene-iron pnictide(FeSe, FeTeSe) and graphene-cuprate(BSCCO) junctions will be described.

  2. 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…

  3. 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

  4. Residential proximity to gasoline service stations and preterm birth.

    PubMed

    Huppé, Vicky; Kestens, Yan; Auger, Nathalie; Daniel, Mark; Smargiassi, Audrey

    2013-10-01

    Preterm birth (PTB) is a growing public health problem potentially associated with ambient air pollution. Gasoline service stations can emit atmospheric pollutants, including volatile organic compounds potentially implicated in PTB. The objective of this study was to evaluate the relationship between residential proximity to gasoline service stations and PTB. Singleton live births on the Island of Montreal from 1994 to 2006 were obtained (n=267,478). Gasoline service station locations, presence of heavy-traffic roads, and neighborhood socioeconomic status (SES) were determined using a geographic information system. Multivariable logistic regression was used to analyze the association between PTB and residential proximity to gasoline service stations (50, 100, 150, 200, 250, and 500 m), accounting for maternal covariates, neighborhood SES, and heavy-traffic roads. For all distance categories beyond 50 m, presence of service stations was associated with a greater odds of PTB. Associations were robust to adjustment for maternal covariates for distance categories of 150 and 200 m but were nullified when adjusting for neighborhood SES. In analyses accounting for the number of service stations, the likelihood of PTB within 250 m was statistically significant in unadjusted models. Associations were, however, nullified in models accounting for maternal covariates or neighborhood SES. Our results suggest that there is no clear association between residential proximity to gasoline service stations in Montreal and PTB. Given the correlation between proximity of gasoline service stations and SES, it is difficult to delineate the role of these factors in PTB.

  5. Interlanguage Pragmatics in the Zone of Proximal Development

    ERIC Educational Resources Information Center

    Ohta, Amy Snyder

    2005-01-01

    Vygotsky's zone of proximal development (ZPD) has been fruitfully applied in L2 research that examines second and foreign language learning. This paper considers the applicability of the ZPD to interlanguage pragmatics instruction and research. First, the ZPD is defined [Vygotsky, L.S., 1978. Mind in Society: The Development of Higher…

  6. Unconventional oil and gas: The role of politics and proximity

    NASA Astrophysics Data System (ADS)

    Schelly, Chelsea

    2016-10-01

    Political divisions are important in understanding public perceptions of unconventional oil and natural gas development, but so is proximity to drilling activities. New research highlights that, as geographical distance from development areas increases, political ideology becomes more influential in explaining diverging perceptions.

  7. The Grammaticalization of the Proximative in Tok Pisin.

    ERIC Educational Resources Information Center

    Romaine, Suzanne

    1999-01-01

    Discusses grammaticalization of "laik" in Tok Pisin, meaning "want/like/desire" (from English "like") and "klostu," meaning "near" (from English "close to") as markers of proximative. Shows although "klostu" was more generally a feature of Pacific Pidgin English and began to grammaticalize in mid-19th century, is now in competition with "laik," a…

  8. 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

  9. Reflections on the Ecolab and the Zone of Proximal Development

    ERIC Educational Resources Information Center

    Luckin, Rosemary; du Boulay, Benedict

    2016-01-01

    In 1999 we reported a study that explored the way that Vygotsky's Zone of Proximal Development could be used to inform the design of an Interactive Learning Environment called the Ecolab. Two aspects of this work have subsequently been used for further research. Firstly, there is the interpretation of the ZPD and its associated theory that was…

  10. Bridging Pedagogies: Drama, Multiliteracies, and the Zone of Proximal Development

    ERIC Educational Resources Information Center

    Macy, Leonora

    2016-01-01

    This article examines how one educator embraced Vygotsky's concept of the zone of proximal development (ZPD) while using drama to scaffold learning about Dr. Seuss's "The Lorax" for first-grade students. This learning event is interpreted with reference to the ZPD and the New London Group's pedagogy of multiliteracies. The author asserts…

  11. Conservative Treatment for Bilateral Displaced Proximal Humerus Head Fracture

    PubMed Central

    Velutini-Becker, Ricardo; Aguilar-Alcalá, Luis D

    2016-01-01

    Proximal humerus fracture represents five to eight percent of all fractures and is twice as common in women than in men. Most cases of displaced fracture of the proximal humerus are treated surgically; it is probable that more cases are preferred to be treated surgically greater than required. The optimal treatment for these fractures remains controversial, but physicians have a tendency to treat via open reduction and fixation with angular locking plates or glenohumeral arthroplasty.  We present a case of a 71-year-old woman with bilateral displaced proximal humeral fracture. Conservative treatment was initiated with two hanging casts, achieving radiological reduction on week one. After two additional weeks of casting, treatment continued with radiologic control and home physical therapy, ultimately an excellent functional outcome and adequate radiological reduction was obtained.    Even in bilaterally displaced proximal humerus fractures, conservative treatment can be an efficient option, reducing complications, reaching adequate functional results and acceptable radiographic reduction.​ PMID:27489750

  12. Trabecular bone ontogeny in the human proximal femur.

    PubMed

    Ryan, Timothy M; Krovitz, Gail E

    2006-12-01

    Ontogenetic changes in the human femur associated with the acquisition of bipedal locomotion, especially the development of the bicondylar angle, have been well documented. The purpose of this study is to quantify changes in the three-dimensional structure of trabecular bone in the human proximal femur in relation to changing functional and external loading patterns with age. High-resolution X-ray computed tomography scan data were collected for 15 juvenile femoral specimens ranging in age from prenatal to approximately nine years of age. Serial slices were collected for the entire proximal femur of each individual with voxel resolutions ranging from 0.017 to 0.046 mm depending on the size of the specimen. Spherical volumes of interest were defined within the proximal femur, and the bone volume fraction, trabecular thickness, trabecular number, and fabric anisotropy were calculated in three dimensions. Bone volume fraction, trabecular number, and degree of anisotropy decrease between the age of 6 months and 12 months, with the lowest values for these parameters occurring in individuals near 12 months of age. By age 2-3 years, the bone volume, thickness, and degree of anisotropy increase slightly, and regions in the femoral neck become more anisotropic corresponding to the thickening of the inferior cortical bone of the neck. These results suggest that trabecular structure in the proximal femur reflects the shift in external loading patterns associated with the initiation of unassisted walking in infants.

  13. Isolated musculocutaneous neuropathy caused by a proximal humeral exostosis.

    PubMed

    Juel, V C; Kiely, J M; Leone, K V; Morgan, R F; Smith, T; Phillips, L H

    2000-01-25

    We report an isolated musculocutaneous neuropathy caused by a proximal humeral osteochondroma that became symptomatic after the patient played recreational basketball. Lesion resection resulted in complete deficit resolution. Mass lesions involving the musculocutaneous nerve should be considered in patients with atraumatic, isolated musculocutaneous neuropathies that are recurrent or fail to recover, even in the setting of strenuous exercise.

  14. Indices of risk assessment of fracture of the proximal humerus

    PubMed Central

    Giannotti, Stefano; Bottai, Vanna; Dell’osso, Giacomo; Donati, Daniela; Bugelli, Giulia; De Paola, Gaia; Guido, Giulio

    2012-01-01

    Summary Osteoporotic fractures are now a social problem for incidence and costs. Fractures of the proximal humerus events are frequent and constantly increasing. It is estimated that they are 20% of all osteoporotic fractures. Bone densitometry in most cases underestimates the real humeral bone density. There is little information about osteoporotic changes in the proximal humerus and their association with the cortical thickness of the humeral shaft. The ratio between the thickness of the cortical and the total diameter of the humeral diaphysis is the cortical index. Fracture risk limit value is 0.231. Convinced of the need to quantify in a reproducible way the real local humerus bone density, we performed a comparative evaluation of bone density of the humerus and femur in patients admitted to our clinic for fractures of the humerus and femur. We evaluated 28 women treated surgically for a fragility fracture of the proximal humerus or femur neck in 2010. All cortical index obtained were lower than the limit for fracture risk set at 0.231, so the IC was more predictive of neck medial fractures of the femur than had DEXA and the U.S. The information about the cortical index may provide a simple way of determining the bone quality of the proximal humerus and of facilitating decision-making in the surgical treatment of patients with fractures of the humerus. So we want to emphasize the importance of therapy for osteoporosis even in patients with fractures of the proximal humerus, which often have not critical densitometric values of femur or column, but they are at risk of new fractures. PMID:22783334

  15. The He II Proximity Effect and The Lifetime of Quasars

    NASA Astrophysics Data System (ADS)

    Khrykin, I. S.; Hennawi, J. F.; McQuinn, M.; Worseck, G.

    2016-06-01

    The lifetime of quasars is fundamental for understanding the growth of supermassive black holes, and is an important ingredient in models of the reionization of the intergalactic medium (IGM). However, despite various attempts to determine quasar lifetimes, current estimates from a variety of methods are uncertain by orders of magnitude. This work combines cosmological hydrodynamical simulations and 1D radiative transfer to investigate the structure and evolution of the He ii Lyα proximity zones around quasars at z ≃ 3-4. We show that the time evolution in the proximity zone can be described by a simple analytical model for the approach of the He ii fraction {x}{He{{II}}}(t) to ionization equilibrium, and use this picture to illustrate how the transmission profile depends on the quasar lifetime, quasar UV luminosity, and the ionization state of Helium in the ambient IGM (i.e., the average He ii fraction, or equivalently the metagalactic He ii ionizing background). A significant degeneracy exists between the lifetime and the average He ii fraction, however the latter can be determined from measurements of the He ii Lyα optical depth far from quasars, allowing the lifetime to be measured. We advocate stacking existing He ii quasar spectra at z ˜ 3, and show that the shape of this average proximity zone profile is sensitive to lifetimes as long as ˜30 Myr. At higher redshift z ˜ 4 where the He ii fraction is poorly constrained, degeneracies will make it challenging to determine these parameters independently. Our analytical model for He ii proximity zones should also provide a useful description of the properties of H i proximity zones around quasars at z ≃ 6-7.

  16. A procedure to estimate proximate analysis of mixed organic wastes.

    PubMed

    Zaher, U; Buffiere, P; Steyer, J P; Chen, S

    2009-04-01

    In waste materials, proximate analysis measuring the total concentration of carbohydrate, protein, and lipid contents from solid wastes is challenging, as a result of the heterogeneous and solid nature of wastes. This paper presents a new procedure that was developed to estimate such complex chemical composition of the waste using conventional practical measurements, such as chemical oxygen demand (COD) and total organic carbon. The procedure is based on mass balance of macronutrient elements (carbon, hydrogen, nitrogen, oxygen, and phosphorus [CHNOP]) (i.e., elemental continuity), in addition to the balance of COD and charge intensity that are applied in mathematical modeling of biological processes. Knowing the composition of such a complex substrate is crucial to study solid waste anaerobic degradation. The procedure was formulated to generate the detailed input required for the International Water Association (London, United Kingdom) Anaerobic Digestion Model number 1 (IWA-ADM1). The complex particulate composition estimated by the procedure was validated with several types of food wastes and animal manures. To make proximate analysis feasible for validation, the wastes were classified into 19 types to allow accurate extraction and proximate analysis. The estimated carbohydrates, proteins, lipids, and inerts concentrations were highly correlated to the proximate analysis; correlation coefficients were 0.94, 0.88, 0.99, and 0.96, respectively. For most of the wastes, carbohydrate was the highest fraction and was estimated accurately by the procedure over an extended range with high linearity. For wastes that are rich in protein and fiber, the procedure was even more consistent compared with the proximate analysis. The new procedure can be used for waste characterization in solid waste treatment design and optimization.

  17. Carbonylation Modification Regulates Na/K-ATPase Signaling and Salt Sensitivity: A Review and a Hypothesis

    PubMed Central

    Shah, Preeya T.; Martin, Rebecca; Yan, Yanling; Shapiro, Joseph I.; Liu, Jiang

    2016-01-01

    Na/K-ATPase signaling has been implicated in different physiological and pathophysiological conditions. Accumulating evidence indicates that oxidative stress not only regulates the Na/K-ATPase enzymatic activity, but also regulates its signaling and other functions. While cardiotonic steroids (CTS)-induced increase in reactive oxygen species (ROS) generation is an intermediate step in CTS-mediated Na/K-ATPase signaling, increase in ROS alone also stimulates Na/K-ATPase signaling. Based on literature and our observations, we hypothesize that ROS have biphasic effects on Na/K-ATPase signaling, transcellular sodium transport, and urinary sodium excretion. Oxidative modulation, in particular site specific carbonylation of the Na/K-ATPase α1 subunit, is a critical step in proximal tubular Na/K-ATPase signaling and decreased transcellular sodium transport leading to increases in urinary sodium excretion. However, once this system is overstimulated, the signaling, and associated changes in sodium excretion are blunted. This review aims to evaluate ROS-mediated carbonylation of the Na/K-ATPase, and its potential role in the regulation of pump signaling and sodium reabsorption in the renal proximal tubule (RPT). PMID:27445847

  18. Carbonylation Modification Regulates Na/K-ATPase Signaling and Salt Sensitivity: A Review and a Hypothesis.

    PubMed

    Shah, Preeya T; Martin, Rebecca; Yan, Yanling; Shapiro, Joseph I; Liu, Jiang

    2016-01-01

    Na/K-ATPase signaling has been implicated in different physiological and pathophysiological conditions. Accumulating evidence indicates that oxidative stress not only regulates the Na/K-ATPase enzymatic activity, but also regulates its signaling and other functions. While cardiotonic steroids (CTS)-induced increase in reactive oxygen species (ROS) generation is an intermediate step in CTS-mediated Na/K-ATPase signaling, increase in ROS alone also stimulates Na/K-ATPase signaling. Based on literature and our observations, we hypothesize that ROS have biphasic effects on Na/K-ATPase signaling, transcellular sodium transport, and urinary sodium excretion. Oxidative modulation, in particular site specific carbonylation of the Na/K-ATPase α1 subunit, is a critical step in proximal tubular Na/K-ATPase signaling and decreased transcellular sodium transport leading to increases in urinary sodium excretion. However, once this system is overstimulated, the signaling, and associated changes in sodium excretion are blunted. This review aims to evaluate ROS-mediated carbonylation of the Na/K-ATPase, and its potential role in the regulation of pump signaling and sodium reabsorption in the renal proximal tubule (RPT).

  19. Proximate and landscape factors influence grassland bird distributions

    USGS Publications Warehouse

    Cunningham, M.A.; Johnson, D.H.

    2006-01-01

    Ecologists increasingly recognize that birds can respond to features well beyond their normal areas of activity, but little is known about the relative importance of landscapes and proximate factors or about the scales of landscapes that influence bird distributions. We examined the influences of tree cover at both proximate and landscape scales on grassland birds, a group of birds of high conservation concern, in the Sheyenne National Grassland in North Dakota, USA. The Grassland contains a diverse array of grassland and woodland habitats. We surveyed breeding birds on 2015 100 m long transect segments during 2002 and 2003. We modeled the occurrence of 19 species in relation to habitat features (percentages of grassland, woodland, shrubland, and wetland) within each 100-m segment and to tree cover within 200-1600 m of the segment. We used information-theoretic statistical methods to compare models and variables. At the proximate scales, tree cover was the most important variable, having negative influences on 13 species and positive influences on two species. In a comparison of multiple scales, models with only proximate variables were adequate for some species, but models combining proximate with landscape information were best for 17 of 19 species. Landscape-only models were rarely competitive. Combined models at the largest scales (800-1600 m) were best for 12 of 19 species. Seven species had best models including 1600-m landscapes plus proximate factors in at least one year. These were Wilson's Phalarope (Phalaropus tricolor), Sedge Wren (Cistothorus platensis), Field Sparrow (Spizella pusilla), Grasshopper Sparrow (Ammodramus savannarum), Bobolink (Dolychonix oryzivorus), Red-winged Blackbird (Agelaius phoeniceus), and Brown-headed Cowbird (Molothrus ater). These seven are small-bodied species; thus larger-bodied species do not necessarily respond most to the largest landscapes. Our findings suggest that birds respond to habitat features at a variety of

  20. Proximate and landscape factors influence grassland bird distributions.

    PubMed

    Cunningham, Mary Ann; Johnson, Douglas H

    2006-06-01

    Ecologists increasingly recognize that birds can respond to features well beyond their normal areas of activity, but little is known about the relative importance of landscapes and proximate factors or about the scales of landscapes that influence bird distributions. We examined the influences of tree cover at both proximate and landscape scales on grassland birds, a group of birds of high conservation concern, in the Sheyenne National Grassland in North Dakota, USA. The Grassland contains a diverse array of grassland and woodland habitats. We surveyed breeding birds on 2015 100 m long transect segments during 2002 and 2003. We modeled the occurrence of 19 species in relation to habitat features (percentages of grassland, woodland, shrubland, and wetland) within each 100-m segment and to tree cover within 200-1600 m of the segment. We used information-theoretic statistical methods to compare models and variables. At the proximate scales, tree cover was the most important variable, having negative influences on 13 species and positive influences on two species. In a comparison of multiple scales, models with only proximate variables were adequate for some species, but models combining proximate with landscape information were best for 17 of 19 species. Landscape-only models were rarely competitive. Combined models at the largest scales (800-1600 m) were best for 12 of 19 species. Seven species had best models including 1600-m landscapes plus proximate factors in at least one year. These were Wilson's Phalarope (Phalaropus tricolor), Sedge Wren (Cistothorus platensis), Field Sparrow (Spizella pusilla), Grasshopper Sparrow (Ammodramus savannarum), Bobolink (Dolychonix oryzivorus), Red-winged Blackbird (Agelaius phoeniceus), and Brown-headed Cowbird (Molothrus ater). These seven are small-bodied species; thus larger-bodied species do not necessarily respond most to the largest landscapes. Our findings suggest that birds respond to habitat features at a variety of

  1. Interlaminated ice-proximal glacimarine sediments in Muir Inlet, Alaska

    USGS Publications Warehouse

    Mackiewicz, N.E.; Powell, R.D.; Carlson, P.R.; Molnia, B.F.

    1984-01-01

    Muir Inlet in Glacier Bay, Alaska, is a glacial fjord receiving a tremendous volume of sediment annually. The rate of sediment accumulation is greatest proximal to Muir Glacier (about 9 m yr-1) and decreases away from the glacier. The primary sediment sources are meltwater streams discharging at subglacial and ice-marginal positions to form overflows, interflows, and underflows (continuous turbidity currents). Overflows and interflows interact with diurnal tidal currents and their volume and sediment concentration varies diurnally and annually with meltwater discharge. These effects produce cyclic deposits of a thin fine-grained sand or silt lamina that grades normally to a thicker poorly to very poorly sorted mud lamina. This lamina couplet is termed a cyclopel. Underflows are suggested to occur in this glacimarine environment because of conditions unique to subglacial fluvial systems. Underflow deposits occur only in proximal positions (177 ??m) is ubiquitous, though low (<5% by weight), and occurs as isolated particles, frozen pellets, or as lenses that in cores may have a lamina appearance. Proximally, ice-rafted debris is difficult to identify because proximal sediment is often as coarse-grained. Deposited sediment may be reworked by tidal currents, and sediment gravity flows. Depositional processes operating in Muir Inlet produce interlaminated sand/silt/clay that characterizes sediment proximal to a glacier and fines seaward to mud. Sediment is classified into one of three sediment types: 1. (1) Type I sediment is very fine grained (mean 8.65-7.17 ??), low in sand (0.1-11.2%), and very poorly to poorly sorted. It is the dominant sediment type in Muir Inlet, and is transported by plumes and deposited by suspension settling. 2. (2) Type II sediment is fine- to coarse-grained (mean 6.70-3.12 ??), low to high in sand (5.1-86.6%), and very poorly to moderately sorted. It represents reworked sediment, proximal plume deposits, or coarse-grained laminae of cyclopels

  2. Prostaglandin E2 increases proximal tubule fluid reabsorption, and modulates cultured proximal tubule cell responses via EP1 and EP4 receptors.

    PubMed

    Nasrallah, Rania; Hassouneh, Ramzi; Zimpelmann, Joseph; Karam, Andrew J; Thibodeau, Jean-Francois; Burger, Dylan; Burns, Kevin D; Kennedy, Chris Rj; Hébert, Richard L

    2015-09-01

    Renal prostaglandin (PG) E2 regulates salt and water transport, and affects disease processes via EP1-4 receptors, but its role in the proximal tubule (PT) is unknown. Our study investigates the effects of PGE2 on mouse PT fluid reabsorption, and its role in growth, sodium transporter expression, fibrosis, and oxidative stress in a mouse PT cell line (MCT). To determine which PGE2 EP receptors are expressed in MCT, qPCR for EP1-4 was performed on cells stimulated for 24 h with PGE2 or transforming growth factor beta (TGFβ), a known mediator of PT injury in kidney disease. EP1 and EP4 were detected in MCT, but EP2 and EP3 are not expressed. EP1 was increased by PGE2 and TGFβ, but EP4 was unchanged. To confirm the involvement of EP1 and EP4, sulprostone (SLP, EP1/3 agonist), ONO8711 (EP1 antagonist), and EP1 and EP4 siRNA were used. We first show that PGE2, SLP, and TGFβ reduced H(3)-thymidine and H(3)-leucine incorporation. The effects on cell-cycle regulators were examined by western blot. PGE2 increased p27 via EP1 and EP4, but TGFβ increased p21; PGE2-induced p27 was attenuated by TGFβ. PGE2 and SLP reduced cyclinE, while TGFβ increased cyclinD1, an effect attenuated by PGE2 administration. Na-K-ATPase α1 (NaK) was increased by PGE2 via EP1 and EP4. TGFβ had no effect on NaK. Additionally, PGE2 and TGFβ increased fibronectin levels, reaching 12-fold upon co-stimulation. EP1 siRNA abrogated PGE2-fibronectin. PGE2 also increased ROS generation, and ONO-8711 blocked PGE2-ROS. Finally, PGE2 significantly increased fluid reabsorption by 31 and 46% in isolated perfused mouse PT from C57BL/6 and FVB mice, respectively, and this was attenuated in FVB-EP1 null mice. Altogether PGE2 acting on EP1 and EP4 receptors may prove to be important mediators of PT injury, and salt and water transport.

  3. Expectations in culturally unfamiliar music: influences of proximal and distal cues and timbral characteristics.

    PubMed

    Stevens, Catherine J; Tardieu, Julien; Dunbar-Hall, Peter; Best, Catherine T; Tillmann, Barbara

    2013-01-01

    Listeners' musical perception is influenced by cues that can be stored in short-term memory (e.g., within the same musical piece) or long-term memory (e.g., based on one's own musical culture). The present study tested how these cues (referred to as, respectively, proximal and distal cues) influence the perception of music from an unfamiliar culture. Western listeners who were naïve to Gamelan music judged completeness and coherence for newly constructed melodies in the Balinese gamelan tradition. In these melodies, we manipulated the final tone with three possibilities: the original gong tone, an in-scale tone replacement or an out-of-scale tone replacement. We also manipulated the musical timbre employed in Gamelan pieces. We hypothesized that novice listeners are sensitive to out-of-scale changes, but not in-scale changes, and that this might be influenced by the more unfamiliar timbre created by Gamelan "sister" instruments whose harmonics beat with the harmonics of the other instrument, creating a timbrally "shimmering" sound. The results showed: (1) out-of-scale endings were judged less complete than original gong and in-scale endings; (2) for melodies played with "sister" instruments, in-scale endings were judged as less complete than original endings. Furthermore, melodies using the original scale tones were judged more coherent than melodies containing few or multiple tone replacements; melodies played on single instruments were judged more coherent than the same melodies played on sister instruments. Additionally, there is some indication of within-session statistical learning, with expectations for the initially-novel materials developing during the course of the experiment. The data suggest the influence of both distal cues (e.g., previously unfamiliar timbres) and proximal cues (within the same sequence and over the experimental session) on the perception of melodies from other cultural systems based on unfamiliar tunings and scale systems. PMID

  4. Expectations in culturally unfamiliar music: influences of proximal and distal cues and timbral characteristics

    PubMed Central

    Stevens, Catherine J.; Tardieu, Julien; Dunbar-Hall, Peter; Best, Catherine T.; Tillmann, Barbara

    2013-01-01

    Listeners' musical perception is influenced by cues that can be stored in short-term memory (e.g., within the same musical piece) or long-term memory (e.g., based on one's own musical culture). The present study tested how these cues (referred to as, respectively, proximal and distal cues) influence the perception of music from an unfamiliar culture. Western listeners who were naïve to Gamelan music judged completeness and coherence for newly constructed melodies in the Balinese gamelan tradition. In these melodies, we manipulated the final tone with three possibilities: the original gong tone, an in-scale tone replacement or an out-of-scale tone replacement. We also manipulated the musical timbre employed in Gamelan pieces. We hypothesized that novice listeners are sensitive to out-of-scale changes, but not in-scale changes, and that this might be influenced by the more unfamiliar timbre created by Gamelan “sister” instruments whose harmonics beat with the harmonics of the other instrument, creating a timbrally “shimmering” sound. The results showed: (1) out-of-scale endings were judged less complete than original gong and in-scale endings; (2) for melodies played with “sister” instruments, in-scale endings were judged as less complete than original endings. Furthermore, melodies using the original scale tones were judged more coherent than melodies containing few or multiple tone replacements; melodies played on single instruments were judged more coherent than the same melodies played on sister instruments. Additionally, there is some indication of within-session statistical learning, with expectations for the initially-novel materials developing during the course of the experiment. The data suggest the influence of both distal cues (e.g., previously unfamiliar timbres) and proximal cues (within the same sequence and over the experimental session) on the perception of melodies from other cultural systems based on unfamiliar tunings and scale systems

  5. PROXIMAL FEMORAL EPIPHYSIOLYSIS AND SUBCLINICAL HYPOTHYROIDISM: CASE REPORT

    PubMed Central

    de Mello, Grasiele Correa; Grossi, Gabriela; Coelho, Sílvio Pereira

    2015-01-01

    Proximal femoral epiphysiolysis is an orthopedic disease that is prevalent during adolescence, because this coincides with the time of greatest growth of osteomuscular structures. Curiously, some patients present this disease early, and this outcome converts to the possible etiological explanation that the slippage might occur through a growth spurt. For these patients, the genesis of the slippage has not yet been elucidated, but endocrine disorders have been noted as possible causes. In an attempt to strengthen the theory of endocrinological etiology and present the results from surgical treatment for this pathological condition, the case of a male patient aged 9 years and 3 months with proximal femoral epiphysiolysis and subclinical hypothyroidism who was diagnosed and treated at our university's teaching hospital is reported here. PMID:27047883

  6. 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

  7. Proximal gastric vagotomy: a district general hospital experience.

    PubMed Central

    Wood, J. J.; Ryan, J. M.; Anders, C. J.

    1983-01-01

    A district general hospital experience with proximal gastric vagotomy over a nine-year period is reported. One hundred and eight patients undergoing the operation for chronic duodenal ulcer were assessed. The follow-up period was 1-9 years (mean 4 years and 7 months). The results were graded using a modification of the classification of Visick (1948). Over 85% of our patients were satisfied with their results. (Visick 1 and 2). Recurrent ulceration was noted in 3.9% of our series (4 cases). There were no deaths and few complications. The technique used by us is described briefly and the role of proximal gastric vagotomy in a district general hospital is discussed. PMID:6859783

  8. Longitudinal Proximity Effects in Superconducting Transition-Edge Sensors

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

    We have found experimentally that the critical current of a square superconducting transition-edge sensor (TES) depends exponentially upon the side length L and the square root of the temperature T. As a consequence, the effective transition temperature T(sub c) of the TES is current-dependent and at fixed current scales as 1/L(sup 2). We also have found that the critical current can show clear Fraunhofer-like oscillations in an applied magnetic field, similar to those found in Josephson junctions. The observed behavior has a natural theoretical explanation in terms of longitudinal proximity effects if the TES is regarded as a weak link between superconducting leads. We have observed the proximity effect in these devices over extraordinarily long lengths exceeding 100 microns.

  9. Longitudinal Proximity Effects in Superconducting Transition-Edge Sensors

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

    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(sub c) of the TES is current-dependent and at fixed current scales as 1/L(sup 2). We also have 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 micrometers, 1450 times the mean-free path.

  10. Longitudinal Proximity Effects in Superconducting Transition-Edge Sensors

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    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(sub c) of the TES is current-dependent and at fixed current scales as 1/L(sup 2). We also have 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 micrometers, 1450 times the mean-free path.

  11. 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.

  12. Proximal humeral osteoarticular allografts: technique, pearls and pitfalls, outcomes.

    PubMed

    Farfalli, German L; Ayerza, Miguel A; Muscolo, D Luis; Aponte-Tinao, Luis A

    2015-12-01

    Allograft transplantation is a biologic reconstruction option for massive bone defects after resection of bone sarcomas. This type of reconstruction not only restores bone stock but it also allows us to reconstruct the joint anatomically. These factors are a major concern, especially in a young and active population.We are describing indications, surgical techniques, pearls and pitfalls, and outcomes of proximal humeral osteoarticular allografts, done at present time in our institution.We found that allograft fractures and articular complications, as epiphyseal resorption and subchondral fracture, are the main complications observed in proximal humerus osteoarticular allograft reconstructions. Nevertheless, only fractures need a reconstruction revision. Joint complications may adversely affect the limb function, but for this reason, an allograft revision is rarely performed.

  13. Perceptual grouping in Gabor lattices: proximity and alignment.

    PubMed

    Claessens, Peter M; Wagemans, Johan

    2005-11-01

    We propose the Gabor lattice as a new stimulus designed to deal with multiple organizations in perceptual grouping, allowing both comparison between psychophysical data and neural findings and a systematic investigation of grouping based on several low-level characteristics and their interactions. A Gabor lattice is a geometric lattice with Gabor patches, evoking a multistable global orientation percept. Visual grouping in Gabor lattices with elements aligned in a global orientation was compared with grouping of nonaligned Gabor patches and of Gaussian blobs. The effect sizes of proximity and alignment were estimated in logistic regression analyses. The results confirmed the importance of proximity and local element alignment as factors in dynamic grouping. We also found a small but consistent enhancement of grouping along the global vector orthogonal to the local patch orientations. In light of these results, we further motivate the relevance of these stimuli and the associated experimental paradigm.

  14. Elements of proximal formative assessment in learners' discourse about energy

    NASA Astrophysics Data System (ADS)

    Harrer, Benedikt W.; Scherr, Rachel E.; Wittmann, Michael C.; Close, Hunter G.; Frank, Brian W.

    2012-02-01

    Proximal formative assessment, the just-in-time elicitation of students' ideas that informs ongoing instruction, is usually associated with the instructor in a formal classroom setting. However, the elicitation, assessment, and subsequent instruction that characterize proximal formative assessment are also seen in discourse among peers. We present a case in which secondary teachers in a professional development course at SPU are discussing energy flow in refrigerators. In this episode, a peer is invited to share her thinking (elicitation). Her idea that refrigerators move heat from a relatively cold compartment to a hotter environment is inappropriately judged as incorrect (assessment). The "instruction" (peer explanation) that follows is based on the second law of thermodynamics, and acts as corrective rather than collaborative.

  15. Anterolateral Biplanar Proximal Tibial Opening-Wedge Osteotomy.

    PubMed

    Dean, Chase S; Chahla, Jorge; Moulton, Samuel G; Nitri, Marco; Serra Cruz, Raphael; LaPrade, Robert F

    2016-06-01

    Proximal tibial anterolateral opening-wedge osteotomies have been reported to achieve successful biplanar lower-extremity realignment. Indications for a proximal tibial anterolateral osteotomy include symptomatic genu recurvatum with genu valgus alignment, usually in patients with a flat sagittal-plane tibial slope. The biplanar approach is able to simultaneously address both components of a patient's malalignment with a single procedure. The correction amount is verified with spacers and intraoperative imaging, while correction of the patient's heel height is simultaneously measured. A plate is secured into the osteotomy site, and the site is filled with bone allograft. The anterolateral tibial osteotomy has been reported to be an effective surgical procedure for correcting concomitant genu recurvatum and genu valgus malalignment. PMID:27656374

  16. A critical assessment of proximal macrotexturing on cemented femoral components.

    PubMed

    Duffy, G P; Muratoglu, O K; Biggs, S A; Larson, S L; Lozynsky, A J; Harris, W H

    2001-12-01

    We analyzed the cement-metal interface of 3 different types of femoral components that had proximal macrotexturing after in vitro insertion and after fatigue testing designed to produce debonding and micromotion. These components were compared with clinical retrieval specimens. The cement did not flow into the macrotexturing; rather, hollow, brittle volcanoes or calderas were formed. These fragile protrusions of cement become worn down or abraded by debonded components. This abrasion of cement may contribute to the early and aggressive osteolysis seen in some of these early failures with proximal macrotextured components. The formation of these volcanos and calderas can be aborted by placing bone-cement onto the macrotexturing before stem insertion. This simple technique allows the macrotexturing to be filled with cement. PMID:11742450

  17. Half-TV format MWIR sensor module incorporating proximity electronics

    NASA Astrophysics Data System (ADS)

    Ashcroft, A. P.; Richardson, L.; Harji, J.; Giuliano, F.

    2012-06-01

    The Osprey-E sensor module consists of an integrated detector-cooler assembly (IDCA) and custom proximity electronics mounted in a lightweight, ruggedized housing. Based on the half-TV format Osprey FPA, it implements recent improvement in SELEX Galileo's array hybridization technique. Ongoing tests have shown that performance is not significantly degraded after more than 5000 cooldown cycles. The FPA exploits SELEX Galileo's High Operating Temperature (HOT) HgCdTe (MCT) and is optimized for operation at 110K. Very low levels of defective pixels (<0.003%) have been achieved at this temperature. The proximity electronics are a new design that originates from SELEX Galileo's Centre of Excellence in Infrared Detectors. The electronics provide all the necessary supplies and signals for detector operation and digitize the detector output into 14-bit digital video. The sensor has been developed to offer a very lightweight, rugged camera core particularly suited to airborne applications.

  18. Ultimate and proximate mechanisms of reciprocal altruism in rats.

    PubMed

    Dolivo, Vassilissa; Rutte, Claudia; Taborsky, Michael

    2016-09-01

    The reciprocal exchange of goods and services among social partners is a conundrum in evolutionary biology because of its proneness to cheating, but also the behavioral and cognitive mechanisms involved in such mutual cooperation are hotly debated. Extreme viewpoints range from the assumption that, at the proximate level, observed cases of "direct reciprocity" can be merely explained by basic instrumental and Pavlovian association processes, to the other extreme implying that "cultural factors" must be involved, as is often attributed to reciprocal cooperation among humans. Here we argue that neither one nor the other extreme conception is likely to explain proximate mechanisms underlying reciprocal altruism in animals. In particular, we outline that Pavlovian association processes are not sufficient to explain the documented reciprocal cooperation among Norway rats, as has been recently argued. PMID:27495930

  19. A Surviving Child With Complete Proximal Tracheal Atresia

    PubMed Central

    Haight, Ken; Sankaran, Koravangattu; Shokeir, Mohamed

    1984-01-01

    An infant was born with an unusual combination of primitive foregut anomalies consisting of complete proximal tracheal atresia, proximal esophageal atresia and distal tracheoesophageal fistula. Before the birth, the family physician suspected an anomaly of the upper airway or esophageal occlusion on the basis of hydramnios evident at the thirty-third to thirty-fourth week of gestation, and earlier amniocentesis which indicated a normal level of α-fetoprotein. He consulted the hospital obstetrics and neonatology departments, which were thus prepared to deal with a potential airway problem at the birth. At birth, prompt airway management, including tracheostomy, prevented anoxic damage to the child. Features which should alert the physician to tracheal obstruction include antenatal polyhydramnios; severe respiratory distress without an audible cry and palpable distal trachea in the newborn; and failure to advance the endotracheal tube beyond the infant's vocal cords. PMID:21279046

  20. Scintillation Proximity Radioimmunoassay Utilizing 125I-Labeled Ligands

    NASA Astrophysics Data System (ADS)

    Udenfriend, Sidney; Diekmann Gerber, Louise; Brink, Larry; Spector, Sydney

    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 125I-labeled antigen is added it binds to the beads and, by its proximity, the emitted short-range electrons of the 125I 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.

  1. 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.

  2. Do people remember the temporal proximity of unrelated events?

    PubMed

    Friedman, William J; Janssen, Steve M J

    2010-12-01

    In the present study, we tested the ability to remember the temporal proximity of two unrelated events that had happened within 7 days of one another. In three experiments, 1,909 participants judged whether pairs of news events, ranging in age from 1 month to about 6 years, had occurred within a week of each other and, if not, how far apart they had occurred. Some event pairs were related, and others were unrelated. For unrelated event pairs, same-week and separation judgments were very poor. Accuracy was much greater for both kinds of judgments when the events were related. Participants often guessed the separation of unrelated event pairs, whereas they frequently deduced the separation or remembered the proximity of related event pairs. For both types of pairs, the participants reported using the strength of the memories or the general period in which the events had occurred.

  3. 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.

  4. Proximity nanovalve with large phase-tunable thermal conductance

    SciTech Connect

    Strambini, E. Giazotto, F.; Bergeret, F. S.

    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/Φ{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.

  5. 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.

  6. Proximity potential for heavy ion reactions on deformed nuclei

    SciTech Connect

    Baltz, A. J.; Bayman, B. F.

    1982-01-01

    The usual treatment of the deformed optical model for analysis of heavy ion induced inelastic scattering data involves a deformed (target) radius, a spherical (projectile) radius and a potential strength dependent on the surface separation along the line between the two centers. Several authors using various approaches have shown that this center line potential is geometrically inadequate especially for description of higher L deformation parameters probed in heavy ion induced inelastic scattering experiments. A quantitatively adequate form of the deformed proximity potential suitable for use with a coupled channels reaction code in the analysis of inelastic scattering data above the Coulomb barrier is described. A major objective is to be able to extract reliably higher deformed multipole moments from such data. The deformed potential calculated in the folding model will serve as a geometrically exact benchmark to evaluate the accuracy of the proximity potential prescriptions. (WHK)

  7. Lung cancer, proximity to industry, and poverty in northeast England.

    PubMed Central

    Pless-Mulloli, T; Phillimore, P; Moffatt, S; Bhopal, R; Foy, C; Dunn, C; Tate, J

    1998-01-01

    This study assesses whether deprived populations living close to industry experience greater mortality from lung cancer than populations with comparable socioeconomic characteristics living farther away. Mortality data, census data, a postal survey of living circumstances, historic and contemporary data on air quality and a historic land-use survey were used. Analysis was based on two conurbations in England, Teesside and Sunderland. Housing estates in Teesside were selected based on socioeconomic criteria and distinguished by proximity to steel and chemical industries; they were grouped into three zones: near (A), intermediate (B), and farther (C), with a single zone in Sunderland. We included 14,962 deaths in 27 estates. Standardized mortality ratios (SMR) for lung cancer [International Classification of Diseases #9 (ICD-9) 162] and cancers other than lung (ICD-9 140-239, excluding 162), and sex ratios were calculated. Mortality from lung cancer was well above national levels in all zones. For men, a weak gradient corresponding with proximity to industry at younger ages reversed at older ages. In women 0-64 years of age, stronger gradients in lung cancer mortality corresponded with proximity to industry across zones A, B, and C (SMR = 393, 251, 242, respectively). Overall rates in Teesside were higher than Sunderland rates for women aged 0-64 years (SMR = 287 vs. 185) and 65-74 years (SMR = 190 vs. 157). The association between raised lung cancer mortality and proximity to industry in women under 75 years of age could not be explained by smoking, occupation, socioeconomic factors, or artifact. Explanations for differences between men and women may include gender-specific occupational experiences and smoking patterns. Our judgment is that the observed gradient in women points to a role for industrial air pollution. Images Figure 1 Figure 2 PMID:9485483

  8. Does spatial proximity drive norovirus transmission during outbreaks in hospitals?

    PubMed Central

    Harris, John P; Lopman, Ben A; Cooper, Ben S; O'Brien, Sarah J

    2013-01-01

    Objective To assess the role of spatial proximity, defined as patients sharing bays, in the spread of norovirus during outbreaks in hospitals. Design Enhanced surveillance of norovirus outbreaks between November 2009 and November 2011. Methods Data were gathered during 149 outbreaks of norovirus in hospital wards from five hospitals in two major cities in England serving a population of two million. We used the time between the first two cases of each outbreak to estimate the serial interval for norovirus in this setting. This distribution and dates of illness onset were used to calculate epidemic trees for each outbreak. We then used a permutation test to assess whether proximity, for all outbreaks, was more extreme than would be expected by chance under the null hypothesis that proximity was not associated with transmission risk. Results 65 outbreaks contained complete data on both onset dates and ward position. We estimated the serial interval to be 1.86 days (95% CI 1.6 to 2.2 days), and with this value found strong evidence to reject the null hypothesis that proximity was not significant (p<0.001). Sensitivity analysis using different values of the serial interval showed that there was evidence to reject the null hypothesis provided the assumed serial interval was less than 2.5 days. Conclusions Our results provide evidence that patients occupying the same bay as patients with symptomatic norovirus infection are at an increased risk of becoming infected by these patients compared with patients elsewhere in the same ward. PMID:23852138

  9. Mesoscale Nanoparticles Selectively Target the Renal Proximal Tubule Epithelium

    PubMed Central

    Williams, Ryan M.; Shah, Janki; Ng, Brandon D.; Minton, Denise R.; Gudas, Lorraine J.; Park, Christopher Y.; Heller, Daniel A.

    2015-01-01

    We synthesized “mesoscale” nanoparticles, approximately 400 nm in diameter, which unexpectedly localized selectively in renal proximal tubules and up to 7 times more efficiently in the kidney than other organs. Although nanoparticles typically localize in the liver and spleen, modulating their size and opsonization potential allowed for stable targeting of the kidneys through a new proposed uptake mechanism. Applying this kidney targeting strategy, we anticipate use in the treatment of renal disease and the study of renal physiology. PMID:25811353

  10. Proximal Interruption of the Pulmonary Artery: A Case Series.

    PubMed

    Anand, S H; Jasper, Anitha; Mani, Sunithi Elizabeth; Joseph, Elizabeth; Mathai, John

    2015-12-01

    We present a few cases of Proximal Interruption of the Pulmonary Artery, an uncommon developmental anomaly associated with congenital heart disease. The cases had varied clinical presentations. Chest radiograph showed a hypoplastic lung with an ipsilateral small hilum on the side of the interruption and hyperinflation of the contralateral lung. Contrast CT confirmed the diagnosis, demonstrating non-visualization of the left or right pulmonary artery, and other related findings. PMID:26816968

  11. Moulded cement-prosthesis for osteosarcoma of the proximal humerus.

    PubMed

    Pan, K L; Ong, G B; Potukuchi, A P

    2006-12-01

    We report a case of an 11-year-old boy with osteosarcoma of the proximal humerus treated with wide excision and reconstruction with a cement spacer-prosthesis. After seven years of follow-up, the patient is now almost a young adult. We present his current physical and functional status, which seems to defray the initial doubts regarding long-term problems when we chose this method of reconstruction. PMID:17600994

  12. Prevalence of rotator cuff tears in operative proximal humerus fractures.

    PubMed

    Choo, Andrew; Sobol, Garret; Maltenfort, Mitchell; Getz, Charles; Abboud, Joseph

    2014-11-01

    Proximal humerus fractures and rotator cuff tears have been shown to have increasing rates with advancing age, theoretically leading to significant overlap in the 2 pathologies. The goal of this study was to examine the prevalence, associated factors, and effect on treatment of rotator cuff tears in surgically treated proximal humerus fractures. A retrospective review was performed of all patients who had surgery for a proximal humerus fracture from January 2007 to June 2012 in the shoulder department of a large academic institution. Patient demographics, the presence and management of rotator cuff tears, and surgical factors were recorded. Regression analysis was performed to determine which factors were associated with rotator cuff tears. This study reviewed 349 fractures in 345 patients. Of these, 30 (8.6%) had concomitant rotator cuff tears. Those with a rotator cuff tear were older (average age, 68.7 vs 63.1 years), were more likely to have had a dislocation (40% vs 12.5%), and were more likely to have undergone subsequent arthroscopic repair or reverse total shoulder arthroplasty than those without a rotator cuff tear. Most (22 of 30) were treated with suture repair at the time of surgery, but 5 patients underwent reverse total shoulder arthroplasty based primarily on the intraoperative finding of a significant rotator cuff tear. A concomitant rotator cuff tear in association with a proximal humerus fracture is relatively common. Rotator cuff tears are associated with older patients and those with a fracture-dislocation. In rare cases, these cases may require the availability of a reverse shoulder prosthesis. PMID:25361372

  13. Proximal humerus shaft fracture after pectoralis major tendon rupture repair.

    PubMed

    Silverstein, Jeff A; Goldberg, Ben; Wolin, Preston

    2011-06-01

    Surgical repair of a complete pectoralis major tendon rupture at the humeral insertion has superior results compared to nonoperative treatment. To our knowledge, a proximal humerus shaft fracture occurring at the site of the bone trough and cortical drill holes after a pectoralis major tendon rupture repair has not been reported in the literature.A 45-year-old man sustained an acute left pectoralis major tendon rupture at the humeral insertion while performing a bench press maneuver. He underwent acute surgical repair. Approximately 8 weeks postoperatively, the patient fell from a standing height and sustained a proximal humerus shaft fracture through the repair site at the bone trough. Three days after the fracture, the patient underwent open reduction and internal fixation of the proximal humerus shaft fracture and exploration of the pectoralis major tendon repair. The fracture was found to be at the level of the repair site, and the pectoralis major tendon was completely intact to the distal fragment. The fracture healed uneventfully, and the patient regained full motion and strength of his extremity with no limitations.Any type of surgical fixation that creates a hole in the humerus or decreases the cross-sectional area such as a bone trough creates a stress riser. Patients undergoing pectoralis tendon repair that involves violating the humerus with a bone trough or hole have a slight risk of postoperative humerus fracture, especially if sustaining an early traumatic event such as a fall. PMID:21667914

  14. The kinetochore prevents centromere-proximal crossover recombination during meiosis

    PubMed Central

    Vincenten, Nadine; Kuhl, Lisa-Marie; Lam, Isabel; Oke, Ashwini; Kerr, Alastair RW; Hochwagen, Andreas; Fung, Jennifer; Keeney, Scott; Vader, Gerben; Marston, Adèle L

    2015-01-01

    During meiosis, crossover recombination is essential to link homologous chromosomes and drive faithful chromosome segregation. Crossover recombination is non-random across the genome, and centromere-proximal crossovers are associated with an increased risk of aneuploidy, including Trisomy 21 in humans. Here, we identify the conserved Ctf19/CCAN kinetochore sub-complex as a major factor that minimizes potentially deleterious centromere-proximal crossovers in budding yeast. We uncover multi-layered suppression of pericentromeric recombination by the Ctf19 complex, operating across distinct chromosomal distances. The Ctf19 complex prevents meiotic DNA break formation, the initiating event of recombination, proximal to the centromere. The Ctf19 complex independently drives the enrichment of cohesin throughout the broader pericentromere to suppress crossovers, but not DNA breaks. This non-canonical role of the kinetochore in defining a chromosome domain that is refractory to crossovers adds a new layer of functionality by which the kinetochore prevents the incidence of chromosome segregation errors that generate aneuploid gametes. DOI: http://dx.doi.org/10.7554/eLife.10850.001 PMID:26653857

  15. Proximate and elemental analyses of Tinospora cordifolia stem.

    PubMed

    Mahima; Rahal, Anu; Prakash, Atul; Verma, Amit Kumar; Kumar, Vinod; Roy, Debashish

    2014-05-01

    Tinospora cordifolia also known as Giloy or Guduchi, is an indigenous climber plant indigenous to tropical areas of India, Myanmar and Sri Lanka. Its stem is used for treatment of fever, jaundice, emaciation, skin ailments, diabetes, anaemia and various infectious diseases. The study was undertaken to evaluate the proximate and elemental analysis of the stems of Tinospora cordifolia. The proximate analyses were carried out using standard methods, while mineral elements were analyzed using Atomic Absorption Spectrophotometer, equipped with air acetylene flame. The proximate analysis of the stems of Tinospora cordifolia showed that it contained moisture 34.39%, ether extract 0.912%, crude protein 7.74%, crude fibre 56.42%, total ash 7.96%, nitrogen free extract 26.97%, cellulose 23.02% and hemicellulose 3.70%. The mineral analysis of the stems showed that they contain the following essential minerals: Calcium (102.23 ppm), phosphorous (24.81 ppm), iron (26.058 ppm), copper (3.733 ppm), zinc (7.342 ppm) and manganese (12.242 ppm). The study revealed that Tinospora cordifolia stems to be a potential source of nutrition and minerals for man as well as animals. PMID:26031012

  16. Proximity interactions among centrosome components identify regulators of centriole duplication.

    PubMed

    Firat-Karalar, Elif Nur; Rauniyar, Navin; Yates, John R; Stearns, Tim

    2014-03-17

    The centrosome consists of a pair of centrioles and surrounding pericentriolar material (PCM). Many vertebrate cells also have an array of granules, termed centriolar satellites, that localize around the centrosome and are associated with centrosome and cilium function. Centriole duplication occurs once per cell cycle and is effected by a set of proteins including PLK4, CEP192, CEP152, CEP63, and CPAP. Information on the relationships between these components is limited due to the difficulty in assaying interactions in the context of the centrosome. Here, we used proximity-dependent biotin identification (BioID) to identify proximity interactions among centriole duplication proteins. PLK4, CEP192, and CEP152 BioID identified known physically interacting proteins and a new interaction between CEP152 and CDK5RAP2 consistent with a function of CEP152 in PCM recruitment. BioID for CEP63 and its paralog CCDC67 revealed extensive proximity interactions with centriolar satellite proteins. Focusing on these satellite proteins identified two new regulators of centriole duplication, CCDC14 and KIAA0753. Both proteins colocalize with CEP63 to satellites, bind to CEP63, and identify other satellite proteins by BioID. KIAA0753 positively regulates centriole duplication and CEP63 centrosome localization, whereas CCDC14 negatively regulates both processes. These results suggest that centriolar satellites have a previously unappreciated function in regulating centriole duplication. PMID:24613305

  17. PROXIMITY TO AN EXERCISE FACILITY AND PHYSICAL ACTIVITY IN CHINA.

    PubMed

    Ani, Ruopeng; Zheng, Jiakun

    2014-11-01

    Physical inactivity is a major risk factor for premature morbidity and mortality. We studied the relationship between proximity to an exercise facility and leisure time physical activity in China. We conducted a questionnaire-based survey of 10 provinces in China during 2012 among 5,000 respondents with a completion rate of 82.1%. Respondents were asked about leisure time physical activity, defined as any exercise during the week. Respondents were also asked if they lived within 10 minutes walking distance from an exercise facility. The association between proximity to an exercise facility and physical activity were examined with multivariate regression analysis while attempting to control for sociodemographic factors and province of residence. Proximity to an exercise facility was found to be positively associated with leisure time physical activity. Individuals living within 10 minutes walking distance from an exercise facility were 6.79% (95% confidence interval: 3.67-10.01) more likely to have any leisure time physical activity than those who lived more than 10 minutes walking distance from an exercise facility. Physical exercise among females, younger adults, people with a higher education and urban residents appeared to have a greater association with distance to an exercise facility. Improving accessibility to an exercise facility might increase the likelihood of leisure time physical activity, especially among working-age urban Chinese.

  18. Effects of Hip Geometry on Fracture Patterns of Proximal Femur

    PubMed Central

    Kazemi, Seyyed Morteza; Qoreishy, Mohamad; Keipourfard, Ali; Sajjadi, Mohammadreza Minator; Shokraneh, Shahram

    2016-01-01

    Background: Some studies have previously shown that geometry of proximal femur can affect the probability of fracture and type of fracture. It happens since the geometry of the proximal femur determines how a force is applied to its different parts. In this study, we have compared proximal femur’s geometric characteristics in femoral neck (FNF), intertrochanteric (ITF) and Subtrochanteric (STF) fractures. Methods: In this study, 60 patients who had hip fractures were studied as case studies. They were divided into FNF, ITF and STF groups based on their fracture types (20 patients in each group). Patients were studied with x-ray radiography and CT scans. Radiological parameters including femoral neck length from lateral cortex to center of femoral head (FNL), diameter of femoral head (FHD), diameter of femoral neck (FND), femoral head neck offset (FHNO), neck-shaft angle (alpha), femoral neck anteversion (beta) were measured and compared in all three groups. Results: Amount of FNL was significantly higher in STF group compared to FNF (0.011) while ITF and STF as well as FNT and ITF did not show a significant different. Also, FND in FNF group was significantly lower than the other two groups, i.e. ITF and STF. In other cases there were no instances of significant statistical difference. Conclusion: Hip geometry can be used to identify individuals who are at the risk of fracture with special pattern. Also, it is important to have more studies in different populations and more in men. PMID:27517071

  19. The kinetochore prevents centromere-proximal crossover recombination during meiosis.

    PubMed

    Vincenten, Nadine; Kuhl, Lisa-Marie; Lam, Isabel; Oke, Ashwini; Kerr, Alastair Rw; Hochwagen, Andreas; Fung, Jennifer; Keeney, Scott; Vader, Gerben; Marston, Adèle L

    2015-12-14

    During meiosis, crossover recombination is essential to link homologous chromosomes and drive faithful chromosome segregation. Crossover recombination is non-random across the genome, and centromere-proximal crossovers are associated with an increased risk of aneuploidy, including Trisomy 21 in humans. Here, we identify the conserved Ctf19/CCAN kinetochore sub-complex as a major factor that minimizes potentially deleterious centromere-proximal crossovers in budding yeast. We uncover multi-layered suppression of pericentromeric recombination by the Ctf19 complex, operating across distinct chromosomal distances. The Ctf19 complex prevents meiotic DNA break formation, the initiating event of recombination, proximal to the centromere. The Ctf19 complex independently drives the enrichment of cohesin throughout the broader pericentromere to suppress crossovers, but not DNA breaks. This non-canonical role of the kinetochore in defining a chromosome domain that is refractory to crossovers adds a new layer of functionality by which the kinetochore prevents the incidence of chromosome segregation errors that generate aneuploid gametes.

  20. Scheduling in Heterogeneous Computing Environments for Proximity Queries.

    PubMed

    Kim, Duksu; Lee, Jinkyu; Lee, Junghwan; Shin, Insik; Kim, John; Yoon, Sunggeui

    2013-04-01

    We present a novel, Linear Programming (LP) based scheduling algorithm that exploits heterogeneous multi-core architectures such as CPUs and GPUs to accelerate a wide variety of proximity queries. To represent complicated performance relationships between heterogeneous architectures and different computations of proximity queries, we propose a simple, yet accurate model that measures the expected running time of these computations. Based on this model, we formulate an optimization problem that minimizes the largest time spent on computing resources, and propose a novel, iterative LP-based scheduling algorithm. Since our method is general, we are able to apply our method into various proximity queries that have different characteristics. Our method achieves an order of magnitude performance improvement by using four different GPUs and two hexa-core CPUs over using a hexa-core CPU only. Unlike prior scheduling methods, our method continually improves the performance, as we add more computing resources. Also, our method achieves much higher performance improvement compared with prior methods as heterogeneity of computing resources is increased. We also show that our method provides results that are close to the performance provided by a conservative upper bound of the ideal throughput. These results demonstrate the efficiency and robustness of our algorithm that have not been achieved by prior methods.

  1. Progenitor Cells in Proximal Airway Epithelial Development and Regeneration

    PubMed Central

    Lynch, Thomas J.; Engelhardt, John F.

    2015-01-01

    Multiple distinct epithelial domains are found throughout the airway that are distinguishable by location, structure, function, and cell-type composition. Several progenitor cell populations in the proximal airway have been identified to reside in confined microenvironmental niches including the submucosal glands (SMGs), which are embedded in the tracheal connective tissue between the surface epithelium and cartilage, and basal cells that reside within the surface airway epithelium (SAE). Current research suggests that regulatory pathways that coordinate development of the proximal airway and establishment of progenitor cell niches may overlap with pathways that control progenitor cell responses during airway regeneration following injury. SMGs have been shown to harbor epithelial progenitor cells, and this niche is dysregulated in diseases such as cystic fibrosis. However, mechanisms that regulate progenitor cell proliferation and maintenance within this glandular niche are not completely understood. Here we discuss glandular progenitor cells during development and regeneration of the proximal airway and compare properties of glandular progenitors to those of basal cell progenitors in the SAE. Further investigation into glandular progenitor cell control will provide a direction for interrogating therapeutic interventions to correct aberrant conditions affecting the SMGs in diseases such as cystic fibrosis, chronic bronchitis, and asthma. PMID:24818588

  2. Proximal Rectus Femoris Avulsion: Ultrasonic Diagnosis and Nonoperative Management

    PubMed Central

    Esser, Stephan; Jantz, David; Hurdle, Mark F.; Taylor, Walter

    2015-01-01

    Objective To present a case of ultrasonic diagnosis and nonoperative management of a complete proximal rectus femoris avulsion in a National Collegiate Athletic Association Division 1 soccer goalkeeper. Background While delivering a goal kick, a previously uninjured 24-year-old collegiate soccer goalkeeper had the sudden onset of right anterior thigh pain. He underwent rehabilitation with rapid resolution of his presenting pain but frequent intermittent recurrence of anterior thigh pain. After he was provided a definitive diagnosis with musculoskeletal ultrasound, he underwent an extended period of rehabilitation and eventually experienced complete recovery without recurrence. Differential Diagnosis Rectus femoris avulsion, rectus femoris strain or partial tear, inguinal hernia, or acetabular labral tear. Treatment Operative and nonoperative options were discussed. In view of the player's recovery, nonoperative options were pursued with a good result. Uniqueness Complete proximal rectus femoris avulsions are rare. Our case contributes to the debate on whether elite-level kicking and running athletes can return to full on-field performance without surgery. Conclusions Complete proximal rectus femoris avulsions can be treated effectively using nonoperative measures with good preservation of function even in the elite-level athlete. In addition, musculoskeletal ultrasound is an excellent tool for on-site evaluation and may help guide prognosis and management. PMID:25978099

  3. Proximity interactions among centrosome components identify regulators of centriole duplication.

    PubMed

    Firat-Karalar, Elif Nur; Rauniyar, Navin; Yates, John R; Stearns, Tim

    2014-03-17

    The centrosome consists of a pair of centrioles and surrounding pericentriolar material (PCM). Many vertebrate cells also have an array of granules, termed centriolar satellites, that localize around the centrosome and are associated with centrosome and cilium function. Centriole duplication occurs once per cell cycle and is effected by a set of proteins including PLK4, CEP192, CEP152, CEP63, and CPAP. Information on the relationships between these components is limited due to the difficulty in assaying interactions in the context of the centrosome. Here, we used proximity-dependent biotin identification (BioID) to identify proximity interactions among centriole duplication proteins. PLK4, CEP192, and CEP152 BioID identified known physically interacting proteins and a new interaction between CEP152 and CDK5RAP2 consistent with a function of CEP152 in PCM recruitment. BioID for CEP63 and its paralog CCDC67 revealed extensive proximity interactions with centriolar satellite proteins. Focusing on these satellite proteins identified two new regulators of centriole duplication, CCDC14 and KIAA0753. Both proteins colocalize with CEP63 to satellites, bind to CEP63, and identify other satellite proteins by BioID. KIAA0753 positively regulates centriole duplication and CEP63 centrosome localization, whereas CCDC14 negatively regulates both processes. These results suggest that centriolar satellites have a previously unappreciated function in regulating centriole duplication.

  4. Scheduling in Heterogeneous Computing Environments for Proximity Queries.

    PubMed

    Kim, Duksu; Lee, Jinkyu; Lee, Junghwan; Shin, Insik; Kim, John; Yoon, Sunggeui

    2013-04-01

    We present a novel, Linear Programming (LP) based scheduling algorithm that exploits heterogeneous multi-core architectures such as CPUs and GPUs to accelerate a wide variety of proximity queries. To represent complicated performance relationships between heterogeneous architectures and different computations of proximity queries, we propose a simple, yet accurate model that measures the expected running time of these computations. Based on this model, we formulate an optimization problem that minimizes the largest time spent on computing resources, and propose a novel, iterative LP-based scheduling algorithm. Since our method is general, we are able to apply our method into various proximity queries that have different characteristics. Our method achieves an order of magnitude performance improvement by using four different GPUs and two hexa-core CPUs over using a hexa-core CPU only. Unlike prior scheduling methods, our method continually improves the performance, as we add more computing resources. Also, our method achieves much higher performance improvement compared with prior methods as heterogeneity of computing resources is increased. We also show that our method provides results that are close to the performance provided by a conservative upper bound of the ideal throughput. These results demonstrate the efficiency and robustness of our algorithm that have not been achieved by prior methods. PMID:23568962

  5. Proximity hybridization-triggered signal switch for homogeneous chemiluminescent bioanalysis.

    PubMed

    Zong, Chen; Wu, Jie; Liu, Mengmeng; Yang, Linlin; Liu, Lin; Yan, Feng; Ju, Huangxian

    2014-06-01

    A proximity hybridization-triggered signal switch was presented for convenient homogeneous chemiluminescent detection of a wide range of affinity target biomolecules, such as oligonucleotides, protein biomarkers, and aptamer-recognized targets. The presence of the target promoted the formation of a proximate complex via the proximity hybridization of two help DNA strands or the DNA strands labeled to affinity ligands, which subsequently unfolded the self-reporting molecular beacon to switch on the chemiluminescence signal. The response could be further amplified with an in situ enzymatic recycling strategy for highly sensitive chemiluminescence detection. By using an antibody as the affinity ligand, this simple protocol could sensitively detect protein biomarker in a concentration range of 6 orders of magnitude with a detection limit down to 80 fM. With the use of an aptamer as the affinity ligand, a method for homogeneous chemiluminescent detection of thrombin was proposed. The one-step and wash-free assay showed good selectivity and required only 1 μL of sample. Its high sensitivity, acceptable accuracy, and satisfactory versatility of analytes led to various applications in bioanalysis.

  6. SLAP tear associated with a minimally displaced proximal humerus fracture.

    PubMed

    Kendall, Corey B; Tanner, Stephanie L; Tolan, Stefan J

    2007-12-01

    Nondisplaced proximal humerus fracture may be associated with soft tissue injury. This case report examines 2 cases of superior labral anterior-posterior (SLAP) tears in association with nondisplaced fractures of the proximal humerus. In the first case, the patient fell from a jet ski, causing a traction injury to his arm. A greater tuberosity fracture was identified. Magnetic resonance imaging (MRI) did not reveal a definitive labral tear. After conservative management had failed, a type IV SLAP tear and a small rotator cuff tear were arthroscopically identified and repaired. In the second case, a power company lineman fell from a lift and attempted to hold on with his dominant arm. A nondisplaced greater tuberosity and a surgical neck fracture were discovered. MR arthrography revealed no evidence of SLAP tear. Four months after injury, a type II SLAP tear was arthroscopically identified and repaired. In these 2 cases, the presence of the fracture likely slowed operative intervention because pain was attributed to the fracture itself, and not to the SLAP tear. If patients do not follow the usual course of improvement after a proximal humerus fracture from a superior traction mechanism, consideration should be given to associated superior labral tears that may require surgical intervention.

  7. Links between casino proximity and gambling participation, expenditure, and pathology.

    PubMed

    Sévigny, Serge; Ladouceur, Robert; Jacques, Christian; Cantinotti, Michael

    2008-06-01

    Two studies investigated the relationship between casino proximity and gambling participation, expenditure, and pathology. In Study 1, 8,842 participants were categorized into 1 of 4 driving distances from their home to the nearest casino in the province of Quebec: 0-100 km, 100.01-200 km, 200.01-300 km, or 300.01-981 km. In Study 2, 5,158 participants, who lived within a 100-km driving distance from the Montreal casino, were classified into 1 of 5 equidistant, 20-km driving distances. A survey company interviewed participants regarding their gambling habits. Results indicated a positive link between casino proximity and gambling participation (at the provincial and Montreal levels) and expenditure (at the provincial level only) but no link with the current prevalence rate of probable pathological gambling or of problem gambling. In a setting in which many types of gambling activities are available, casino proximity in itself does not appear to explain the rate of gambling-related problems. It is necessary to continue prospective research on exposure and adaptation theories as potential explanations for the development of pathological gambling.

  8. Proximity hybridization regulated DNA biogate for sensitive electrochemical immunoassay.

    PubMed

    Ren, Kewei; Wu, Jie; Zhang, Yue; Yan, Feng; Ju, Huangxian

    2014-08-01

    An electrochemical DNA biogate was designed for highly sensitive homogeneous electrochemical immunoassay by combining target-induced proximity hybridization with a mesoporous silica nanoprobe (MSN). The electroactive methylene blue (MB) was sealed in the inner pores of MSN with single-stranded DNA. In the presence of target protein and two DNA-labeled antibodies, the formed proximate complex could hybridize with the DNA strand to form a rigid double-stranded structure and thus open the biogate, which led to the release of MB entrapped in the MSN. The target protein-dependent amount of released MB could be conveniently monitored with a screen-printed carbon electrode. Moreover, the detachment process of MB could be further amplified with an in situ enzymatic recycling binding of the proximate complex with the single-stranded DNA. Using prostate-specific antigen as a model target, the proposed assay showed a wide detection range from 0.002 to 100 ng mL(-1) with a detection limit of 1.3 pg mL(-1). This strategy was simple and universal for various analytes with different affinity ligands. This method possessed great potential for convenient point-of-care testing and commercial application.

  9. Proximal femur segmentation in conventional pelvic x ray

    SciTech Connect

    Pilgram, Roland; Walch, Claudia; Kuhn, Volker; Schubert, Rainer; Staudinger, Roland

    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.

  10. Isolated acute dislocation of the proximal tibiofibular joint.

    PubMed

    Iosifidis, Michael I; Giannoulis, Ioannis; Tsarouhas, Alexandros; Traios, Stavros

    2008-06-01

    Lesions of knee's lateral side are less common than medial injuries. The anatomy of the lateral ligaments and the presence of additional structures (eg, fibula head) can cause diagnostic problems. Isolated dislocation of the proximal tibiofibular joint is unusual; therefore, it may be overlooked in the emergency department. Many cases are missed due to failure of diagnosis. This type of injury is common in athletes whose sports require twisting motions of the flexed knee (eg, wrestling, parachute jumping, judo, gymnastics, skiing, rugby, football, soccer, track, baseball, basketball, racquetball, and roller-skating). Anterolateral dislocation of the proximal tibiofibular joint is seemingly rare in soccer players, as less than a handful cases have been reported in the literature. The diagnosis can be made by clinical examination, plain knee radiographs, and, sometimes, computed tomography (CT) scanning for further confirmation. Treatment usually consists of closed or open reduction. In complicated cases, however, arthrodesis or resection of the fibular head may be required. This article reports a rare case of acute isolated anterolateral dislocation of the proximal tibiofibular joint in a soccer player and discusses the joint anatomy, types of dislocations, mechanisms of injury, and treatment options.

  11. Cysteine mutagenesis reveals alternate proximity between transmembrane domain 2 and hairpin loop 1 of the glutamate transporter EAAT1.

    PubMed

    Zhang, Yunlong; Zhang, Xiuping; Qu, Shaogang

    2014-07-01

    Excitatory amino acid transporter 1 (EAAT1) plays an important role in restricting the neurotoxicity of glutamate. Previous structure-function studies have provided evidence that reentrant helical hairpin loop (HP) 1 has predominant function during the transport cycle. The proposed internal gate HP1 is packed against transmembrane domain (TM) 2 and TM5 in its closed state, and two residues located in TM2 and HP2 of EAAT1 are in close proximity. However, the spatial relationship between TM2 and HP1 during the transport cycle remains unknown. In this study, we used chemical cross-linking of introduced cysteine pair (V96C and S366C) in a cysteine-less version of EAAT1 to assess the proximity of TM2 and HP1. Here, we show that inhibition of transport by copper(II)(1,10-phenanthroline)3 (CuPh) and cadmium ion (Cd(2+)) were observed in the V96C/S366C mutant. Glutamate or potassium significantly protected against the inhibition of transport activity of V96C/S366C by CuPh, while TBOA potentiated the inhibition of transport activity of V96C/S366C by CuPh. We also checked the kinetic parameters of V96C/S366C treated with or without CuPh in the presence of NaCl, NaCl + L-glutamate, NaCl + TBOA, and KCl, respectively. The sensitivity of V96C and S366C to membrane-impermeable sulfhydryl reagent MTSET [(2-trimethylammonium) methanethiosulfonate] was attenuated by glutamate or potassium. TBOA had no effect on the sensitivity of V96C and S366C to MTSET. These data suggest that the spatial relationship between Val-96 of TM2 and Ser-366 of HP1 is altered in the transport cycle.

  12. Correction for etch proximity: new models and applications

    NASA Astrophysics Data System (ADS)

    Granik, Yuri

    2001-09-01

    Short-range etch proximity effects increase intra-die CD variability and degrade the IC performance and yield. Tight control of the etch bias is an increasingly critical factor in realizing the ITRS technology nodes. The 2000 technology nodes revision added a new category, the post-etch 'physical' gate length metric, that is 9 - 17% smaller than 'in-resist' gate length. We present new etch proximity correction methods and models designed to reduce negative impact of etch-induced CD variability and increase uniformity of the controlled over- etching. Resolution Enhancement Technologies (RET) design correction methods typically employ 'lumped' process models. We found that an alternative methodology based upon separation of the process factors and the related models may yield better accuracy, performance, and better suit the design and process optimization flows. The contributions from the reticle, the optics, the wafer, and etch are individually determined and then used either separately or in aggregation for the most flexible and optimum correction of their respective contributions. The etch corrections are based on the Variable Etch Bias model (VEB model). This semi-empirical model requires experimental CD information to be collected from the test patterns under fixed process conditions (point-process model). It demonstrates excellent fit to the early experimental CD-SEM data gathered to date, which spans a variety of layout features and process conditions. The VEB model works in conjunction with CalibreR software system's Variable Threshold Resist-Extended (VTR-E) model, however the etching is modeled separately from the optics and the resist processing. This yields better understanding and more accurate explanation of the experiments than those that are produced by the 'lumped' process modeling. The VEB model explains etch- induced bias in terms of the following three proximity characteristics or variables: effective trench width (or pattern separation), pattern

  13. Proximal clamping levels in abdominal aortic aneurysm surgery.

    PubMed Central

    Büket, S; Atay, Y; Islamoğlu, F; Yağdi, T; Posacioğlu, H; Alat, I; Cikirikçioğlu, M; Yüksel, M; Durmaz, I

    1999-01-01

    In the surgical treatment of abdominal aortic aneurysm, the single proximal cross-clamp can be placed at 3 alternative aortic levels: infrarenal, hiatal, and thoracic. We performed this retrospective study to evaluate the advantages and disadvantages of the 3 main aortic clamping locations. Eighty patients presented at our institution with abdominal aortic aneurysms from March 1993 through May 1998. Fifty of these patients had intact aneurysms and underwent elective surgery, and 30 had ruptured aneurysms that necessitated emergency surgery. Proximal aortic clamping was applied at the infrarenal level in 24 patients (22 from the intact aneurysm group, 2 from the ruptured group), at the hiatal level in 34 patients (22 intact, 12 ruptured), and at the thoracic level (descending aorta) via a limited left lateral thoracotomy in 22 patients (6 intact, 16 ruptured). Early mortality rates (within 30 days) were 4% (2 of 50 patients) among patients with intact aneurysms and 40% (12 of 30 patients) among those with ruptured aneurysms. In the 2 patients from the intact aneurysm group, proximal aortic clamps were applied at the hiatal level. In the ruptured aneurysm group, proximal aortic clamps were placed at the thoracic level in 10 patients, the infrarenal level in 1, and the hiatal level in 1. According to our study, the clinical status of the patient and the degree of operative urgency--as determined by the extent of the aneurysm--generally dictate the proximal clamp location. Patients who present with aneurysmal rupture or hypovolemic shock benefit from thoracic clamping, because it restores the blood pressure and allows time to replace the volume deficit. Infrarenal placement is advantageous in patients with intact aneurysms if there is sufficient space for the clamp between the renal arteries and the aortic aneurysm. In patients with juxtarenal aneurysms, hiatal clamping enables safe and easy anastomosis to the healthy aorta. Clamping at this level also helps prevent

  14. Clinical results of using the proximal humeral internal locking system plate for internal fixation of displaced proximal humeral fractures.

    PubMed

    Norouzi, Masoud; Naderi, Mohammad Nasir; Komasi, Mehdi Hemmati; Sharifzadeh, Seyyed Reza; Shahrezaei, Mostafa; Eajazi, Alireza

    2012-05-01

    Proximal humerus fractures are accounting for 4-5% of all fractures with increasing incidence. Proximal Humeral Internal Locking System (PHILOS) plate is a new plate which permits early mobility and lowers the risk of complications. The aim of this study was to evaluate the functional outcome and the complication rate after using this plate. Between 2006-2008, 37 patients with displaced 2-, 3-, and 4-part fractures of the proximal humerus underwent surgery using PHILOS plate. The mean range of follow-up was 12 months. Twenty patients were aged 60 years and younger, and 17 were aged older than 60 years. The average American Shoulder and Elbow Surgeons (ASES) score at the final follow-up was 77.62. According to Michener and colleagues classification, 5.4% of patients had an excellent outcome, 72.9% were minimally functionally limited, 16.2% were moderately functionally limited, and 5.4% were maximally functionally limited. The average ASES score between patients 60 years and older and those 60 years and younger was not different significantly. One patient developed avascular necrosis of the humeral head, 2 patients developed an infection, and no patients developed a nonunion. Fixation with PHILOS plate can be considered a good method with high union rates for this kind of fracture, especially in the older population with osteoporotic bone.

  15. 14 CFR 121.360 - Ground proximity warning-glide slope deviation alerting system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Ground proximity warning-glide slope... Equipment Requirements § 121.360 Ground proximity warning-glide slope deviation alerting system. (a) No... turbine-powered airplane unless it is equipped with a ground proximity warning/glide slope...

  16. Spectrophotometric assay of renal ouabain-resistant Na(+)-ATPase and its regulation by leptin and dietary-induced obesity.

    PubMed

    Bełtowski, Jerzy; Jamroz-Wiśniewska, Anna; Nazar, Jarosław; Wójcicka, Grazyna

    2004-01-01

    Apart from Na(+),K(+)-ATPase, a second sodium pump, Na(+)-stimulated, K(+)-independent ATPase (Na(+)-ATPase) is expressed in proximal convoluted tubule of the mammalian kidney. The aim of this study was to develop a method of Na(+)-ATPase assay based on the method previously used by us to measure Na(+),K(+)-ATPase activity. The ATPase activity was assayed as the amount of inorganic phosphate liberated from ATP by isolated microsomal fraction. Na(+)-ATPase activity was calculated as the difference between the activities measured in the presence and in the absence of 50 mM NaCl. Na(+)-ATPase activity was detected in the renal cortex (3.5 +/- 0.2 mumol phosphate/h per mg protein), but not in the renal medulla. Na(+)-ATPase was not inhibited by ouabain or an H(+),K(+)-ATPase inhibitor, Sch 28080, but was almost completely blocked by 2 mM furosemide. Leptin administered intraperitoneally (1 mg/kg) decreased the Na(+),K(+)-ATPase activity in the renal medulla at 0.5 and 1 h by 22.1% and 27.1%, respectively, but had no effect on Na(+)-ATPase in the renal cortex. Chronic hyperleptinemia induced by repeated subcutaneous leptin injections (0.25 mg/kg twice daily for 7 days) increased cortical Na(+),K(+)-ATPase, medullary Na(+),K(+)-ATPase and cortical Na(+)-ATPase by 32.4%, 84.2% and 62.9%, respectively. In rats with dietary-induced obesity, the Na(+),K(+)- ATPase activity was higher in the renal cortex and medulla by 19.7% and 34.3%, respectively, but Na(+)-ATPase was not different from control. These data indicate that both renal Na(+)-dependent ATPases are separately regulated and that up-regulation of Na(+)-ATPase may contribute to Na(+) retention and arterial hypertension induced by chronic hyperleptinemia.

  17. Xanthine effects on renal proximal tubular function and cyclic AMP metabolism.

    PubMed

    Coulson, R; Scheinman, S J

    1989-02-01

    We evaluated the renal effects of xanthines using two in vitro models: the isolated perfused rat kidney (IPRK) and cultured opossum kidney (OK) cells, a continuous cell line that resembles proximal tubule and responds to parathyroid hormone (PTH). 1,3-Diethyl-8-phenylxanthine (DPX) a potent adenosine receptor antagonist, increased urine volume, glomerular filtration rate, vascular resistance and the fractional excretions of Na, K, Ca and Pi in the IPRK. DPX lowered the Na-dependent uptake of Pi by OK cells. By comparison enprofylline, 3-propylxanthine (ENP), a weak adenosine receptor antagonist, produced a slight elevation in glomerular filtration rate but no changes in electrolyte excretion by IPRK or Pi uptake by OK cells. Both DPX and ENP produced negligible elevations in basal IPRK cAMP. A 1-nM bolus of PTH elevated urinary and perfusate cAMP 50- and 10-fold, respectively. PTH-elevated urinary and perfusate cAMP were augmented further 4- to 7-fold with DPX and 3- to 4-fold with ENP (All IPRK experiments used 50 microM xanthine). OK cells produced a 2-fold cAMP response to 10 nM PTH alone. OK cells treated with 50 microM DPX exhibited no increase in basal but a 13-fold increase in PTH-stimulated cell cAMP. The rank order of potency at 50 microM to augment OK cell cAMP with 10 nM PTH was DPX greater than 1,3-dipropyl-8-cyclopentylxanthine (DPC) greater than 1-methyl-3-isobutylxanthine greater than theobromine greater than theophylline greater than caffeine greater than ENP = no effect.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2537403

  18. Antioxidant supplementation normalizes elevated protein kinase C activity in the proximal tubules of old rats.

    PubMed

    Asghar, Mohammad; Lokhandwala, Mustafa F

    2004-03-01

    Aging is associated with increase in oxidative stress. Earlier, we have shown that higher basal protein kinase C (PKC) activity in the proximal tubules (PTs) of old rats contributes to the hyperphosphorylation of Na,K-ATPase and subsequent decrease in basal Na,K-ATPase activity, resulting in diminished natriuretic response to dopamine in these animals. We hypothesized that the increase in PKC activity in PTs of old rats is caused by increased oxidative stress and that antioxidants administration should reduce/normalize the elevated PKC activity in the renal PTs of old rats. We studied the effect of two antioxidants, namely, alpha-lipoic acid (LA) and tempol, on oxidants level and PKC activity in the PTs of adult (6-month) and old (24-month) Fischer 344 rats. We found that the accumulation of fluorescent dichlorofluorescein (DCF), an indicator of oxidant production, was higher in the PTs of old compared to adult rats. Dietary supplementation with LA for 2 weeks normalized the increased DCF level in old rats. Carboxymethylysine and malondialdehyde, markers of oxidative damage, were elevated in the PTs of old rats, which were normalized to the level of adult rats when tempol was provided in drinking water for 3 weeks. Both LA and tempol treatment also normalized the higher basal PKC activity in the PTs of old rats to the level seen in adult rats. These results suggest that increase in oxidative stress causes an increase in PKC activity, and that antioxidants, while reducing oxidative stress, also normalize PKC activity in the PTs of old rats.

  19. Evidence for a role of claudin 2 as a proximal tubular stress responsive paracellular water channel.

    PubMed

    Wilmes, Anja; Aschauer, Lydia; Limonciel, Alice; Pfaller, Walter; Jennings, Paul

    2014-09-01

    Claudins are the major proteins of the tight junctions and the composition of claudin subtypes is decisive for the selective permeability of the paracellular route and thus tissue specific function. Their regulation is complex and subject to interference by several factors, including oxidative stress. Here we show that exposure of cultured human proximal tubule cells (RPTEC/TERT1) to the immunosuppressive drug cyclosporine A (CsA) induces an increase in transepithelial electrical resistance (TEER), a decrease in dome formation (on solid growth supports) and a decrease in water transport (on microporous growth supports). In addition, CsA induced a dramatic decrease in the mRNA for the pore forming claudins -2 and -10, and the main subunits of the Na(+)/K(+) ATPase. Knock down of claudin 2 by shRNA had no discernable effect on TEER or dome formation but severely attenuated apical to basolateral water reabsorption when cultured on microporous filters. Generation of an osmotic gradient in the basolateral compartment rescued water transport in claudin 2 knock down cells. Inhibition of Na(+)/K(+) ATPase with ouabain prevented dome formation in both cell types. Taken together these results provide strong evidence that dome formation is primarily due to transcellular water transport following a solute osmotic gradient. However, in RPTEC/TERT1 cells cultured on filters under iso-osmotic conditions, water transport is primarily paracellular, most likely due to local increases in osmolarity in the intercellular space. In conclusion, this study provides strong evidence that claudin 2 is involved in paracellular water transport and that claudin 2 expression is sensitive to compound induced cellular stress.

  20. Glucose transport and metabolism in rat renal proximal tubules: multicomponent effects of insulin.

    PubMed

    Kleinzeller, A; McAvoy, E M

    1986-04-25

    Glucose transport and metabolism, and the effect of insulin thereon, was studied using suspensions of rat renal tubules enriched in the proximal component. [U-14C]Glucose oxidation is a saturable process (Km 3.1 +/- 0.2 mM; Vmax 14 +/- 0.2 mumole 14CO2 formed/g tissue protein per h). Glucose oxidation and [14C]lactate formation from glucose are inhibited in part by phlorizin and phloretin: the data suggest that the rate-limiting entry of glucose into the cell metabolic pool occurs by both the Na-glucose cotransport system (at the brush border) and the equilibrating, phloretin-sensitive system (at the basal-lateral membrane). Raising external glucose from 5 to 30 mM markedly increases aerobic and anaerobic lactate formation. Gluconeogenesis from lactate is not affected by variations of glucose concentrations. 24 h after streptozotocin administration, aerobic lactate formation is enhanced, as is the uptake of methyl alpha-D-glucoside by the tubules, while anaerobic glycolysis is depressed. Streptozotocin treatment (ST) increases both the Km and Vmax of glucose oxidation; gluconeogenesis and lactate oxidation are not affected. The effect of streptozotocin treatment on lactate formation are abolished by 1 mU/ml insulin. Streptozotocin treatment increases tissue hexokinase activity, decreases glucose-6-phosphatase, but has no significant effect on fructose-1,6-diphosphatase; phosphoenolpyruvate carboxykinase and pyruvate dehydrogenase. The data demonstrate fast streptozotocin-induced changes in cellular enzymes of carbohydrate metabolism. The enhancing effect of streptozotocin on methyl alpha-glucoside uptake is transient: 8 days after administration of the agent, no significant difference from controls is found. It is concluded that under the given experimental conditions insulin enhances the equilibrating glucose entry by the phloretin-sensitive pathway at the basal-lateral membrane, and transiently inhibits the Na-glucose cotransport system.

  1. Proximate composition and caloric content of eight Lake Michigan fishes

    USGS Publications Warehouse

    Rottiers, Donald V.; Tucker, Robert M.

    1982-01-01

    We measured the proximate composition (percentage lipid, water, fat-free dry material, ash) and caloric content of eight species of Lake Michigan fish: lake trout (Salvelinus namaycush), coho salmon (Oncorhynchus kisutch), lake whitefish (Coregonus clupeaformis), bloater (Coregonus hoyi), alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax), deepwater sculpin (Myoxocephalus quadricornis), and slimy sculpin (Cottus cognatus). Except for alewives, proximate composition and caloric content did not differ significantly between males and females. And, for coho salmon, there was no significant difference in composition between fish collected in different years. Lipid and caloric content of lake trout increased directly with age. In all species examined, lipids and caloric contents were significantly lower in small, presumably immature, fish than in larger, older fish. Lipid content of lake trout, lake whitefish, and bloaters (range of means, 16-22%) was nearly 3 times higher than that of coho salmon, sculpins, rainbow smelt, and alewives (range of means, 5.2-7.0%). The mean caloric content ranged from 6.9 to 7.1 kcal/g for species high in lipids and from 5.8 to 6.3 kcal/g for species low in lipids. Although the caloric content of all species varied directly with lipid content and inversely with water content, an increase in lipid content did not always coincide with a proportional increase in caloric content when other components of fish composition were essentially unchanged. This observation suggests that the energy content of fish estimated from the proximate composition by using universal conversion factors may not necessarily be accurate.

  2. Percutaneous Stabilization of Impending Pathological Fracture of the Proximal Femur

    SciTech Connect

    Deschamps, Frederic Farouil, Geoffroy Hakime, Antoine Teriitehau, Christophe Barah, Ali Baere, Thierry de

    2012-12-15

    Objective: Percutaneous osteosynthesis plus cementoplasty (POPC) is a minimally invasive technique that has never been reported before and that we have prospectively evaluated for patients with impending pathological fracture of the proximal femur. Methods: We performed POPC in 12 patients (3 males, 9 females) with metastasis of the proximal femur with a high risk of fracture (Mirels' score {>=}8) between February 2010 and July 2011. Patients were not candidates for standard surgical stabilization. We analyzed the feasibility, duration, and complication of the procedure, the risk of fracture, the decrease in pain (Visual Analog Scale, VAS), and length of stay in hospital. Data were prospectively collected in all patients. Results: The mean Mirels' score was 9.8 {+-} 1.2 (range, 8-11). The technical success was 100%. POPC was performed under general anesthesia (n = 6) or conscious sedation (n = 6). The mean duration was 110 {+-} 43 (range, 60-180) minutes. All patients stood up and walked the second day after the procedure. The average length of stay in the hospital was 4 {+-} 1.6 (range, 2-7) days. We experienced two hematomas in two patients and no thromboembolic complication. For symptomatic patients (n = 8), VAS decreased from 6.5/10 (range, 2-9) before treatment to 1/10 (range, 0-3) 1 month after. No fracture occurred after a median follow-up of 145 (range, 12-608) days. Conclusions: POPC for impending pathological fracture of the proximal femur seems to be a promising alternative for cancer patients who are not candidates for surgical stabilization. Further studies are required to confirm this preliminary experience.

  3. Proximity Effects and Nonequilibrium Superconductivity in Transition-Edge Sensors

    NASA Technical Reports Server (NTRS)

    Sadleir, John E.; Smith, Stephen J.; Robinson, Ian K.; Finkbeiner, Fred M.; Chervenak, James A.; Bandler, Simon R.; Eckart, Megan E.; Kilbourne, Caroline A.

    2011-01-01

    We have recently shown that normal-metal/superconductor (N/S) bilayer TESs (superconducting Transition-Edge Sensors) exhibit weak-link behavior.l Here we extend our understanding to include TESs with added noise-mitigating normal-metal structures (N structures). We find TESs with added Au structures also exhibit weak-link behavior as evidenced by exponential temperature dependence of the critical current and Josephson-like oscillations of the critical current with applied magnetic field. We explain our results in terms of an effect converse to the longitudinal proximity effect (LoPE) 1, the lateral inverse proximity effect (LaiPE), for which the order parameter in the N/S bilayer is reduced due to the neighboring N structures. Resistance and critical current measurements are presented as a function of temperature and magnetic field taken on square Mol Au bilayer TESs with lengths ranging from 8 to 130 {\\mu}m with and without added N structures. We observe the inverse proximity effect on the bilayer over in-plane distances many tens of microns and find the transition shifts to lower temperatures scale approximately as the inverse square of the in- plane N-structure separation distance, without appreciable broadening of the transition width. We also present evidence for nonequilbrium superconductivity and estimate a quasiparticle lifetime of 1.8 \\times 10-10 s for the bilayer. The LoPE model is also used to explain the increased conductivity at temperatures above the bilayer's steep resistive transition.

  4. The proximate unit in Chinese handwritten character production

    PubMed Central

    Chen, Jenn-Yeu; Cherng, Rong-Ju

    2013-01-01

    In spoken word production, a proximate unit is the first phonological unit at the sublexical level that is selectable for production (O'Seaghdha et al., 2010). The present study investigated whether the proximate unit in Chinese handwritten character production is the stroke, the radical, or something in between. A written version of the form preparation task was adopted. Chinese participants learned sets of two-character words, later were cued with the first character of each word, and had to write down the second character (the target). Response times were measured from the onset of a cue character to the onset of a written response. In Experiment 1, the target characters within a block shared (homogeneous) or did not share (heterogeneous) the first stroke. In Experiment 2, the first two strokes were shared in the homogeneous blocks. Response times in the homogeneous blocks and in the heterogeneous blocks were comparable in both experiments (Experiment 1: 687 vs. 684 ms, Experiment 2: 717 vs. 716). In Experiment 3 and 4, the target characters within a block shared or did not share the first radical. Response times in the homogeneous blocks were significantly faster than those in the heterogeneous blocks (Experiment 3: 685 vs. 704, Experiment 4: 594 vs. 650). In Experiment 5 and 6, the shared component was a Gestalt-like form that is more than a stroke, constitutes a portion of the target character, can be a stand-alone character itself, can be a radical of another character but is not a radical of the target character (e.g., ± in , , , ; called a logographeme). Response times in the homogeneous blocks were significantly faster than those in the heterogeneous blocks (Experiment 5: 576 vs. 625, Experiment 6: 586 vs. 620). These results suggest a model of Chinese handwritten character production in which the stroke is not a functional unit, the radical plays the role of a morpheme, and the logographeme is the proximate unit. PMID:23950752

  5. The Proximate Causes of Sexual Size Dimorphism in Phrynocephalus przewalskii

    PubMed Central

    Zhao, Wei; Liu, Nai-fa

    2014-01-01

    Sexual size dimorphism (SSD) is a common phenomenon and is a central topic in evolutionary biology. Recently, the importance of pursuing an ontogenetic perspective of SSD has been emphasized, to elucidate the proximate physiological mechanisms leading to its evolution. However, such research has seldom focused on the critical periods when males and females diverge. Using mark-recapture data, we investigated the development of SSD, sex-specific survivorship, and growth rates in Phrynocephalus przewalskii (Agamidae). We demonstrated that both male and female lizards are reproductively mature at age 10–11 months (including 5 months hibernation). Male-biased SSD in snout-vent length (SVL) was only found in adults and was fully expressed at age 11 months (June of the first full season of activity), just after sexual maturation. However, male-biased SSD in tail length (TL), hind-limb length (LL), and head width (HW) were fully expressed at age 9–10 months, just before sexual maturation. Analysis of age-specific linear growth rates identified sexually dimorphic growth during the fifth growth month (age 10–11 months) as the proximate cause of SSD in SVL. The males experienced higher mortality than females in the first 2 years and only survived better than females after SSD was well developed. This suggests that the critical period of divergence in the sizes of male and female P. przewalskii occurs between 10 and 11 months of age (May to June during the first full season of activity), and that the sexual difference in growth during this period is the proximate cause. However, the sexual difference in survivorship cannot explain the male-biased SSD in SVL. Our results indicate that performance-related characteristics, such as TL, HW, and LL diverged earlier than SVL. The physiological mechanisms underlying the different growth patterns of males and females may reflect different energy allocations associated with their different reproductive statuses. PMID:24465815

  6. Perceptual organization by proximity and similarity in schizophrenia.

    PubMed

    Kurylo, Daniel D; Pasternak, Roey; Silipo, Gail; Javitt, Daniel C; Butler, Pamela D

    2007-09-01

    Perceptual organization represents a basic and essential function that occurs at an intermediate level of visual processing. Much of the previous research on perceptual organization in schizophrenia employed indirect measurements, or included factors beyond sensory processing. The aims of the present study were to determine the integrity of perceptual organization in schizophrenia, as well as to determine the stimulus duration necessary to perform perceptual organization. Psychophysical measurements were compared between patients with schizophrenia and matched control subjects. Participants viewed dot patterns briefly presented on a computer monitor, and indicated whether stimuli appeared grouped as vertical or horizontal lines. Grouping was based upon either relative proximity or similarity in color. Across trials, relative proximity or color similarity was progressively reduced until stimuli became bi-stable (perceived as either of two patterns of grouping), establishing the grouping threshold. In separate conditions, stimuli were immediately followed by a mask to limit processing. Stimulus duration was progressively reduced until stimuli became bi-stable, establishing the critical stimulus duration (CSD). Schizophrenia patients demonstrated elevated grouping thresholds for grouping by proximity as well as color similarity. In addition, CSD was significantly extended for the schizophrenia group, with a nearly four-fold increase in duration of processing. These results provide direct evidence of impairment in schizophrenia for perceptual organization based upon spatial relationships and feature similarity, and suggest deficits in low-level perceptual organization processes. Although this study did not directly investigate the physiological correlates underlying perceptual impairments, these results are consistent with a theory of impaired lateral connections within visual cortical areas in schizophrenia. PMID:17681736

  7. Scheduling in heterogeneous computing environments for proximity queries.

    PubMed

    Kim, Duksu; Lee, Jinkyu; Lee, Junghwan; Shin, Insik; Kim, John; Yoon, Sung-Eui

    2013-09-01

    We present a novel, linear programming (LP)-based scheduling algorithm that exploits heterogeneous multicore architectures such as CPUs and GPUs to accelerate a wide variety of proximity queries. To represent complicated performance relationships between heterogeneous architectures and different computations of proximity queries, we propose a simple, yet accurate model that measures the expected running time of these computations. Based on this model, we formulate an optimization problem that minimizes the largest time spent on computing resources, and propose a novel, iterative LP-based scheduling algorithm. Since our method is general, we are able to apply our method into various proximity queries used in five different applications that have different characteristics. Our method achieves an order of magnitude performance improvement by using four different GPUs and two hexa-core CPUs over using a hexa-core CPU only. Unlike prior scheduling methods, our method continually improves the performance, as we add more computing resources. Also, our method achieves much higher performance improvement compared with prior methods as heterogeneity of computing resources is increased. Moreover, for one of tested applications, our method achieves even higher performance than a prior parallel method optimized manually for the application. We also show that our method provides results that are close (e.g., 75 percent) to the performance provided by a conservative upper bound of the ideal throughput. These results demonstrate the efficiency and robustness of our algorithm that have not been achieved by prior methods. In addition, we integrate one of our contributions with a work stealing method. Our version of the work stealing method achieves 18 percent performance improvement on average over the original work stealing method. This result shows wide applicability of our approach.

  8. Rapid population growth and environmental degradation: ultimate versus proximate factors.

    PubMed

    Shaw, R P

    1989-01-01

    This philosophical review of 2 arguments about responsibility for and solutions to environmental degradation concludes that both sides are correct: the ultimate and the proximal causes. Ultimate causes of pollution are defined as the technology responsible for a given type of pollution, such as burning fossil fuel; proximate causes are defined as situation-specific factors confounding the problem, such as population density or rate of growth. Commoner and others argue that developed countries with low or negative population growth rates are responsible for 80% of world pollution, primarily in polluting technologies such as automobiles, power generation, plastics, pesticides, toxic wastes, garbage, warfaring, and nuclear weapons wastes. Distortionary policies also contribute; examples are agricultural trade protection, land mismanagement, urban bias in expenditures, and institutional rigidity., Poor nations are responsible for very little pollution because poverty allows little waste or expenditures for polluting, synthetic technologies. The proximal causes of pollution include numbers and rate of growth of populations responsible for the pollution. Since change in the ultimate cause of pollution remains out of reach, altering the numbers of polluters can make a difference. Predictions are made for proportions of the world's total waste production, assuming current 1.6 tons/capita for developed countries and 0.17 tons/capita for developing countries. If developing countries grow at current rates and become more wealthy, they will be emitting half the world's waste by 2025. ON the other hand, unsustainable population growth goes along with inadequate investment in human capital: education, health, employment, infrastructure. The solution is to improve farming technologies in the 117 non-self-sufficient countries, fund development in the most unsustainable enclaves of growing countries, break institutionalized socio-political rigidity in these enclaves, and focus on

  9. Scheduling in heterogeneous computing environments for proximity queries.

    PubMed

    Kim, Duksu; Lee, Jinkyu; Lee, Junghwan; Shin, Insik; Kim, John; Yoon, Sung-Eui

    2013-09-01

    We present a novel, linear programming (LP)-based scheduling algorithm that exploits heterogeneous multicore architectures such as CPUs and GPUs to accelerate a wide variety of proximity queries. To represent complicated performance relationships between heterogeneous architectures and different computations of proximity queries, we propose a simple, yet accurate model that measures the expected running time of these computations. Based on this model, we formulate an optimization problem that minimizes the largest time spent on computing resources, and propose a novel, iterative LP-based scheduling algorithm. Since our method is general, we are able to apply our method into various proximity queries used in five different applications that have different characteristics. Our method achieves an order of magnitude performance improvement by using four different GPUs and two hexa-core CPUs over using a hexa-core CPU only. Unlike prior scheduling methods, our method continually improves the performance, as we add more computing resources. Also, our method achieves much higher performance improvement compared with prior methods as heterogeneity of computing resources is increased. Moreover, for one of tested applications, our method achieves even higher performance than a prior parallel method optimized manually for the application. We also show that our method provides results that are close (e.g., 75 percent) to the performance provided by a conservative upper bound of the ideal throughput. These results demonstrate the efficiency and robustness of our algorithm that have not been achieved by prior methods. In addition, we integrate one of our contributions with a work stealing method. Our version of the work stealing method achieves 18 percent performance improvement on average over the original work stealing method. This result shows wide applicability of our approach. PMID:23846096

  10. [Proximate analysis of straw by near infrared spectroscopy (NIRS)].

    PubMed

    Huang, Cai-jin; Han, Lu-jia; Liu, Xian; Yang, Zeng-ling

    2009-04-01

    Proximate analysis is one of the routine analysis procedures in utilization of straw for biomass energy use. The present paper studied the applicability of rapid proximate analysis of straw by near infrared spectroscopy (NIRS) technology, in which the authors constructed the first NIRS models to predict volatile matter and fixed carbon contents of straw. NIRS models were developed using Foss 6500 spectrometer with spectra in the range of 1,108-2,492 nm to predict the contents of moisture, ash, volatile matter and fixed carbon in the directly cut straw samples; to predict ash, volatile matter and fixed carbon in the dried milled straw samples. For the models based on directly cut straw samples, the determination coefficient of independent validation (R2v) and standard error of prediction (SEP) were 0.92% and 0.76% for moisture, 0.94% and 0.84% for ash, 0.88% and 0.82% for volatile matter, and 0.75% and 0.65% for fixed carbon, respectively. For the models based on dried milled straw samples, the determination coefficient of independent validation (R2v) and standard error of prediction (SEP) were 0.98% and 0.54% for ash, 0.95% and 0.57% for volatile matter, and 0.78% and 0.61% for fixed carbon, respectively. It was concluded that NIRS models can predict accurately as an alternative analysis method, therefore rapid and simultaneous analysis of multicomponents can be achieved by NIRS technology, decreasing the cost of proximate analysis for straw.

  11. Ultimate Drivers and Proximate Correlates of Polyandry in Predatory Mites

    PubMed Central

    Schausberger, Peter; Patiño-Ruiz, J. David; Osakabe, Masahiro; Murata, Yasumasa; Sugimoto, Naoya; Uesugi, Ryuji; Walzer, Andreas

    2016-01-01

    Polyandry is more widespread than anticipated from Bateman’s principle but its ultimate (evolutionary) causes and proximate (mechanistic) correlates are more difficult to pinpoint than those of polygyny. Here, we combined mating experiments, quantification of reproductive traits and microsatellite genotyping to determine the fitness implications of polyandry in two predatory mite species, where males are highly polygynous (up to 45 fertilized females during life), whereas females range from monandry to various polyandry levels. The medium-level polyandrous (up to eight male mates possible) Neoseiulus californicus received clear direct and indirect benefits: multiply mated females produced more offspring with higher survival chances over longer times than singly mated females. In contrast, singly and multiply mated females of the low-level polyandrous (commonly two male mates at maximum) Phytoseiulus persimilis produced similar numbers of offspring having similar survival chances. In both species, multiple mating resulted in mixed offspring paternities, opening the chance for indirect fitness benefits such as enhanced genetic compatibility, complementarity and/or variability. However, the female re-mating likelihood and the paternity chance of non-first male mates were lower in P. persimilis than in N. californicus. Regarding proximate factors, in both species first mating duration and female re-mating likelihood were negatively correlated. Based on occasional fertilization failure of first male mates in P. persimilis, and mixed offspring paternities in both species, we argue that fertilization assurance and the chance to gain indirect fitness benefits are the ultimate drivers of polyandry in P. persimilis, whereas those of N. californicus are higher offspring numbers coupled with enhanced offspring viability and possibly other indirect fitness benefits. Overall, the adaptive significance and proximate events well reflected the polyandry levels. Our study provides

  12. 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

  13. Roadway Proximity and Risk of Sudden Cardiac Death in Women

    PubMed Central

    Hart, Jaime E; Chiuve, Stephanie E; Laden, Francine; Albert, Christine M

    2015-01-01

    Background Sudden cardiac death (SCD) is a major source of mortality and is the first manifestation of heart disease for the majority of cases. Thus, there is a definite need to identify risk factors for SCD that can be modified on the population level. Exposure to traffic, measured by residential roadway proximity, has been shown to be associated with an increased risk of cardiovascular disease. Our objective was to determine if roadway proximity was associated with an increased risk of SCD and to compare to the risk of other coronary heart disease (CHD) outcomes. Methods and Results A total of 523 cases of SCD were identified over 26 years of follow-up among 107,130 members of the prospective Nurses’ Health Study. We calculated residential distance to roadways at all residential addresses from 1986–2012. In age- and race-adjusted models, women living within 50 meters of a major roadway had an elevated risk of SCD (HR=1.56; 95%CI: 1.18–2.05). The association was attenuated but still statistically significant after controlling for potential confounders and mediators (HR=1.38; 95%CI:1.04–1.82). The equivalent adjusted HRs for nonfatal myocardial infarction and fatal CHD were 1.08 (95%CI: 0.96–1.23) and 1.24 (95%CI: 1.03–1.50), respectively. Conclusions Among this sample of middle-aged and older women, roadway proximity was associated with an elevated and statistically significant risks of SCD and fatal CHD, even after controlling for other cardiovascular risk factors. PMID:25332277

  14. Rapid population growth and environmental degradation: ultimate versus proximate factors.

    PubMed

    Shaw, R P

    1989-01-01

    This philosophical review of 2 arguments about responsibility for and solutions to environmental degradation concludes that both sides are correct: the ultimate and the proximal causes. Ultimate causes of pollution are defined as the technology responsible for a given type of pollution, such as burning fossil fuel; proximate causes are defined as situation-specific factors confounding the problem, such as population density or rate of growth. Commoner and others argue that developed countries with low or negative population growth rates are responsible for 80% of world pollution, primarily in polluting technologies such as automobiles, power generation, plastics, pesticides, toxic wastes, garbage, warfaring, and nuclear weapons wastes. Distortionary policies also contribute; examples are agricultural trade protection, land mismanagement, urban bias in expenditures, and institutional rigidity., Poor nations are responsible for very little pollution because poverty allows little waste or expenditures for polluting, synthetic technologies. The proximal causes of pollution include numbers and rate of growth of populations responsible for the pollution. Since change in the ultimate cause of pollution remains out of reach, altering the numbers of polluters can make a difference. Predictions are made for proportions of the world's total waste production, assuming current 1.6 tons/capita for developed countries and 0.17 tons/capita for developing countries. If developing countries grow at current rates and become more wealthy, they will be emitting half the world's waste by 2025. ON the other hand, unsustainable population growth goes along with inadequate investment in human capital: education, health, employment, infrastructure. The solution is to improve farming technologies in the 117 non-self-sufficient countries, fund development in the most unsustainable enclaves of growing countries, break institutionalized socio-political rigidity in these enclaves, and focus on

  15. Arteriovenous graft with outflow in the proximal axillary vein.

    PubMed

    Teruya, Theodore H; Schaeffer, David; Abou-Zamzam, Ahmed M; Bianchi, Christian

    2009-01-01

    Arteriovenous access can result in complications including extremity ischemia and swelling. Use of the nondominant upper extremity is preferred because complications will result in less severe disability. The distal axillary vein in the axilla is usually considered to be the end point for arteriovenous access in the upper extremity. Vascular surgeons are familiar with exposure of the proximal axillary artery via an infraclavicular incision. The axillary vein is also easily exposed through this technique. Use of this vein for arteriovenous graft outflow can preserve the dominant arm for future use. Nine patients with arteriovenous grafts with venous outflow in the proximal arm for future use. All patients had exposure to the proximal axillary vein via an infraclavicular incision. There were six women and three men. All patients had multiple failed access in the ipsilateral extremity. One patient had a loop configuration graft, while the six others had a straight graft with arterial inflow via the brachial artery. One patient had a bovine mesenteric vein graft, while the remaining six had expanded polytetrafluoroethylene grafts. Six of the seven patients had ambulatory surgery, while one patient was admitted postoperatively with mental status changes. Patency rates were 78%, with mean follow-up of 16 months. One patient had early failure due to steal and one patient failed at 22 months. Six of seven patients are alive at current follow-up. Three patients required secondary procedures including venous angioplasty (n=2) and subclavian artery stenting (n=1). The infraclavicular axillary vein can be used as an effective outflow for arteriovenous grafts. This procedure can be done as an outpatient surgery with a low complication rate. This procedure can preserve the dominant arm for future access and provides a possible alternative to surgery on another extremity.

  16. Acute mannitol and saline volume expansion in the rat: effect on transepithelial potential difference in proximal tubules.

    PubMed

    Sugo, E; Györy, A Z

    1990-01-01

    1. Transepithelial potential difference (PDte) of proximal tubules was measured in rats under control conditions (C), and mannitol-saline and saline extracellular fluid volume expansion (MVE, SVE, respectively) under conditions of normal net lumen to basal sodium transport. 2. PDte was measured in kidneys bathed with Hartmann's solution or covered with mineral oil under both volume-expanded conditions together with their controls. 3. PDte was significantly lower in kidneys bathed with Hartmann's solution than those covered with oil. 4. In MVE rats, with mineral oil covering the kidneys, PDte (expressed as mean and s.e.m.) was for the control 2.20 +/- 0.05 (n = 45) mV and MVE 1.97 +/- 0.04 (n = 36) mV, lumen positive, a significant reduction of 10% (P less than 0.001). In SVE rats, with mineral oil covering the kidneys, PDte was for C = 2.42 +/- 0.05 (n = 74) mV and SVE = 1.93 +/- 0.03 (n = 67) mV, a significant reduction (P less than 0.001) of 20%. 5. According to thermodynamic considerations, neither of these changes is sufficient to explain the 50% inhibition of Na transport measured previously during MVE and SVE with autologous tubular fluid. The present results offer further evidence supporting the idea that the inhibition of Na transport during MVE and SVE is largely due to inhibition of the active Na transporting step.

  17. Proximity effects on H absorption in ultrathin V layers

    NASA Astrophysics Data System (ADS)

    Pálsson, Gunnar K.; Eriksson, A. K.; Amft, M.; Xin, X.; Liebig, A.; Ólafsson, Sveinn; Hjörvarsson, Björgvin

    2014-07-01

    We discuss proximity effects on the hydrogen uptake in 14 atomic layers of vanadium. The enthalpy and entropy of solution were measured and compared to ab initio density functional calculations. We show that there exists a large difference in the hydrogen uptake of V in Cr/V and Fe/V superlattices, in which the V is under close to identical strain states. The calculations show that neither local strain effects nor charge redistributions can be the cause for the observed effect. This leaves magnetic and long ranged elastic strain fields—neither captured by the current calculations—as possible mechanisms for the observed effects.

  18. 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.

  19. Proximity effect thermometer for local temperature measurements on mesoscopic samples.

    SciTech Connect

    Aumentado, J.; Eom, J.; Chandrasekhar, V.; Baldo, P. M.; Rehn, L. E.; Materials Science Division; Northwestern Univ; Univ. of Chicago

    1999-11-29

    Using the strong temperature-dependent resistance of a normal metal wire in proximity to a superconductor, we have been able to measure the local temperature of electrons heated by flowing a direct-current (dc) in a metallic wire to within a few tens of millikelvin at low temperatures. By placing two such thermometers at different parts of a sample, we have been able to measure the temperature difference induced by a dc flowing in the samples. This technique may provide a flexible means of making quantitative thermal and thermoelectric measurements on mesoscopic metallic samples.

  20. [Tomodensitometry measurements of proximal tibia and acceleration in marathon athletes].

    PubMed

    Gremion, Gérald; Cordey, Jacques; Leyvraz, Pierre-François; Rizzoli, René; Crettenand, Antoinette; Gobelet, Charles; Dériaz, Olivier; Crettenand, Andre

    2004-02-01

    We evaluated bone adaptation of the tibia to mechanical stresses in male marathon runners and in sedentary controls in function of the ground impact measured by accelerometry and of the bone mineral density assessed by peripheral quantitative computed tomography (QCT). Sixty-three subjects (51 runners and 12 controls) were enrolled. All had measurements of bone mineral density of the proximal tibia and of acceleration at the same site during a jogging at 9 km/hour. The results show a significant higher cortical BMD in runners with the higher value of late accelerations (at 50 ms after the contact with the ground). The late acceleration might be related to muscle contraction.

  1. 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

  2. Models of proximate and ultimate causation in psychology.

    PubMed

    Alessi, G

    1992-11-01

    B. F. Skinner saw behavior as a product of three levels of evolution. J. R. Kantor and Gregory Bateson noted similar relations. This article describes and applies basic evolutionary concepts to each level: (a) phylogenic, (b) ontogenic, and (c) cultural evolution. Each level is analyzed in terms of (a) units of selection, (b) variety of units required for the selection process, (c) selection pressures, (d) interactions among levels, and (e) implications for understanding and predicting behavior. Distinguishing between models of proximate and ultimate causation, as in biology, may help clarify research problems posed by, and facilitate better communication among, psychologists. PMID:1482003

  3. Outcome Analysis of Locking Plate Fixation in Proximal Humerus Fracture

    PubMed Central

    Pathak, Abhishek; Gaur, Sanjiv

    2016-01-01

    Introduction Proximal humerus fractures account for approximately 5% of all fractures. Stable minimally displaced fractures can be treated nonoperatively but the management of displaced fractures remain controversial with various modalities of treatment available. Locking plates provide stable fixation and enable early postoperative mobilization specially in osteoporotic proximal humerus fracture. Aim To evaluate the functional outcome of locking plate fixation and to compare the results of two approaches used for fixation. Materials and Methods This prospective study was conducted at a tertiary level hospital between September 2011 to December 2013. PHILOS plates were used for internal fixation of displaced proximal humerus fractures Neer’s type 2 part, 3 part and 4 part fractures on 26 patients (M/F ratio 1.36:1; mean age 46 years). According to Neer classification, 5,12 and 9 patients had displaced 2, 3 and 4 part fractures respectively. Deltopectoral and deltoid splitting approaches were used for fixation on 13 patients each. Functional outcome was assessed using Constant-Murley shoulder score. Graphpad software version 6.0 was used with Chi-square test and Fisher-exact test are used to compare data. The p-value< 0.05 is considered significant. Results Of the 26 patients, all fractures united radiologically and clinically and average constant score at final follow-up was 72.5. At the final follow-up 8 patients had good score, 10 patients had moderate score, 6 patients had excellent outcome and 2 patients had poor outcome according to Constant score. Mean time to union was 12.3 weeks (9 –15 weeks). Four complications (15.4%) were encountered, 2 cases of varus malunion, 1 case of wound infection which required wound debridement and 1 case of screw cut-out in which screw removal was done. Mean constant score in delto splitting approach was 70.9 and 74 in deltopectoral group (p-value= 0.54). No significant difference existed in constant score in 2 approaches

  4. 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.

  5. A General Simulation Method for Multiple Bodies in Proximate Flight

    NASA Technical Reports Server (NTRS)

    Meakin, Robert L.

    2003-01-01

    Methods of unsteady aerodynamic simulation for an arbitrary number of independent bodies flying in close proximity are considered. A novel method to efficiently detect collision contact points is described. A method to compute body trajectories in response to aerodynamic loads, applied loads, and inter-body collisions is also given. The physical correctness of the methods are verified by comparison to a set of analytic solutions. The methods, combined with a Navier-Stokes solver, are used to demonstrate the possibility of predicting the unsteady aerodynamics and flight trajectories of moving bodies that involve rigid-body collisions.

  6. Using image processing techniques on proximity probe signals in rotordynamics

    NASA Astrophysics Data System (ADS)

    Diamond, Dawie; Heyns, Stephan; Oberholster, Abrie

    2016-06-01

    This paper proposes a new approach to process proximity probe signals in rotordynamic applications. It is argued that the signal be interpreted as a one dimensional image. Existing image processing techniques can then be used to gain information about the object being measured. Some results from one application is presented. Rotor blade tip deflections can be calculated through localizing phase information in this one dimensional image. It is experimentally shown that the newly proposed method performs more accurately than standard techniques, especially where the sampling rate of the data acquisition system is inadequate by conventional standards.

  7. Electrodiagnosis of brachial plexopathies and proximal upper extremity neuropathies.

    PubMed

    Simmons, Zachary

    2013-02-01

    This article describes the normal anatomy of the brachial plexus and its major terminal branches, as well as the major causes and clinical presentations of lesions of these structures. An approach to electrodiagnosis of brachial plexopathies and proximal upper extremity neuropathies is provided, with an emphasis on those nerve conduction studies and portions of the needle examination, which permit localization of lesions to specific trunks, cords, and terminal branches. The importance of specific sensory nerve conduction studies for differentiating plexopathies from radiculopathies and mononeuropathies is emphasized.

  8. Early proximal junctional failure in patients with preoperative sagittal imbalance.

    PubMed

    Smith, Micah W; Annis, Prokopis; Lawrence, Brandon D; Daubs, Michael D; Brodke, Darrel S

    2013-10-01

    Study Type Retrospective review. Introduction Sagittal imbalance has been associated with lower health-related quality of life outcomes, and restoration of imbalance is associated with improved outcomes.123 The long constructs used in adult spinal deformity have potential consequences such as proximal junctional kyphosis (PJK). Clinically, the development of PJK may not be as important as failure of the construct or vertebrae at the proximal end. As PJK does not lead to worse clinical outcomes,45 we define the term early proximal junctional failure (EPJF) as fracture, implant failure, or myelopathy due to stenosis at the upper instrumental vertebra (UIV) or UIV + 1 within 6 months of surgery. Objective The purpose of this study is to report the incidence of EPJF in patients who are sagittally imbalanced preoperatively and to identify risk factors postoperatively that correlate with EPJF using commonly reported sagittal balance parameters. Methods We reviewed 197 patients with preoperative sagittal imbalance by at least one of the following: sagittal vertical axis more than 5 cm, global sagittal alignment more than 45 degrees, pelvic incidence-lumbar lordosis more than 10 degrees, or spine-sacral angle less than 120 degrees. Radiographic measurements also included proximal junctional angle, thoracic kyphosis, lumbar lordosis, pelvic parameters, and sagittal balance parameters/formulas, as well as UIV angle, UIV spinosacral angle, and UIV plumb line to assess as potential risk factors. EPJF incidence was calculated postoperatively for each of the accepted sagittal balance parameters/formulas. Results EPJF was observed in 49 of 197 patients (25%) with preoperative sagittal imbalance and was more common in fusions with UIV in the lower thoracic spine (TS) (35%) than in those with UIV in the upper TS (10%) or lumbar (25%) (p = 0.007). Of the 49 EPJF patients, 16 patients (33%) required revision surgery within the first year, for an overall early revision

  9. Retained Urethral Catheter Secondary to Placement in Proximal Ureter.

    PubMed

    McGregor, Thomas B; Sharda, Rajan

    2016-01-01

    We present an unusual complication secondary to indwelling urethral catheter placement. Routine catheter placement by the obstetrics team in a postpartum female leads to retention of the catheter and inability of its removal by both the obstetrics and urology teams. Although a retained urinary catheter is relatively common, inability to remove a catheter secondary to placement inadvertently into a ureter is extremely rare. In this paper we will discuss the options in removing a retained catheter and present our case of a retained catheter secondary to placement within the right proximal ureter.

  10. Nonequilibrium and proximity effects in superconductor-normal metal junctions

    NASA Astrophysics Data System (ADS)

    Kauppila, V. J.; Nguyen, H. Q.; Heikkilä, T. T.

    2013-08-01

    We study the consequences of nonequilibrium heating and inverse proximity effect in normal metal-insulator-superconductor-insulator-normal metal (NISIN) junctions with a simple quasi-one-dimensional model. We especially focus on observables and parameter regions that are of interest in the design of SINIS coolers with quasiparticle traps. We present numerical results calculated by solving the Usadel equation and also present analytical approximations in two limiting cases: a short junction with a non-negligible resistance in both ends and a long junction with a transparent contact at one end.

  11. DIABETIC NEUROPATHY PART 2: PROXIMAL AND ASSYMMETRIC PHENOTYPES

    PubMed Central

    Pasnoor, Mamatha; Dimachkie, Mazen M.; Barohn, Richard J.

    2014-01-01

    Diabetic neuropathies consist of a variety of syndromes resulting from different types of damage to peripheral or cranial nerves. Although distal symmetric polyneuropathy is most common type of diabetic neuropathy, there are many other subtypes of diabetic neuropathies which have been defined since the 1800’s. Included in these descriptions are patients with proximal diabetic, truncal, cranial, median, and ulnar neuropathies. Various theories have been proposed for the pathogenesis of these neuropathies. The treatment of most of these requires tight and stable glycemic control. Spontaneous recovery is seen in most of these conditions with diabetic control Immunotherapies have been tried in some of these conditions but are quite controversial. PMID:23642718

  12. Diabetic neuropathy part 2: proximal and asymmetric phenotypes.

    PubMed

    Pasnoor, Mamatha; Dimachkie, Mazen M; Barohn, Richard J

    2013-05-01

    Diabetic neuropathies consist of a variety of syndromes resulting from different types of damage to peripheral or cranial nerves. Although distal symmetric polyneuropathy is the most common type of diabetic neuropathy, many other subtypes have been defined since the 1800s, including proximal diabetic, truncal, cranial, median, and ulnar neuropathies. Various theories have been proposed for the pathogenesis of these neuropathies. The treatment of most requires tight and stable glycemic control. Spontaneous recovery is seen in most of these conditions with diabetic control. Immunotherapies have been tried in some of these conditions however are controversial.

  13. Proximal Humerus Fracture Plating Through the Extended Anterolateral Approach.

    PubMed

    Gardner, Michael J

    2016-08-01

    Several approaches to the proximal humerus for fracture fixation are possible. The traditional utilitarian approach to the shoulder, the deltopectoral, has distinct disadvantages when performing fracture reduction and locked plating. The anterolateral acromial approach exploits the intermuscular plane between the anterior and middle heads of the deltoid. After identifying the position of the axillary nerve as it crosses this interval, fracture reduction and fixation is performed. Direct access to both the greater and the lesser tuberosities is facilitated. The cancellous surface of the humeral head fragment provides an excellent surface for direct manipulation without further endangering the extraosseous soft tissue attachments. PMID:27441923

  14. Theory of Casimir Forces without the Proximity-Force Approximation.

    PubMed

    Lapas, Luciano C; Pérez-Madrid, Agustín; Rubí, J Miguel

    2016-03-18

    We analyze both the attractive and repulsive Casimir-Lifshitz forces recently reported in experimental investigations. By using a kinetic approach, we obtain the Casimir forces from the power absorbed by the materials. We consider collective material excitations through a set of relaxation times distributed in frequency according to a log-normal function. A generalized expression for these forces for arbitrary values of temperature is obtained. We compare our results with experimental measurements and conclude that the model goes beyond the proximity-force approximation. PMID:27035293

  15. Models of proximate and ultimate causation in psychology.

    PubMed

    Alessi, G

    1992-11-01

    B. F. Skinner saw behavior as a product of three levels of evolution. J. R. Kantor and Gregory Bateson noted similar relations. This article describes and applies basic evolutionary concepts to each level: (a) phylogenic, (b) ontogenic, and (c) cultural evolution. Each level is analyzed in terms of (a) units of selection, (b) variety of units required for the selection process, (c) selection pressures, (d) interactions among levels, and (e) implications for understanding and predicting behavior. Distinguishing between models of proximate and ultimate causation, as in biology, may help clarify research problems posed by, and facilitate better communication among, psychologists.

  16. [Fibrocartilaginous mesenchymoma of the proximal humerus: case report].

    PubMed

    Masquijo, Julio Javier; Sartori, Federico; Innocenti, Sergio

    2014-10-01

    Fibrocartilaginous mesenchymoma (FCM) is a rare tumor that primarily affects the long bones. Few cases have been reported since its description. A case of a 4-year-old boy with FCM located in the humerus is presented. Radiological examination showed an expansive lytic lesion located in the metaphyseal proximal humerus. Magnetic resonance imaging showed soft tissue expansion. Histopathological diagnosis was confirmatory of FCM. Curettage, adjuvant phenolization, and bone grafting with bone substitute, and autologous bone marrow was performed. During a follow-up period of 2 years, there was no evidence of disease progression. FCM should be considered in the differential diagnosis of lytic bone lesions in children and adolescents.

  17. Retained Urethral Catheter Secondary to Placement in Proximal Ureter

    PubMed Central

    Sharda, Rajan

    2016-01-01

    We present an unusual complication secondary to indwelling urethral catheter placement. Routine catheter placement by the obstetrics team in a postpartum female leads to retention of the catheter and inability of its removal by both the obstetrics and urology teams. Although a retained urinary catheter is relatively common, inability to remove a catheter secondary to placement inadvertently into a ureter is extremely rare. In this paper we will discuss the options in removing a retained catheter and present our case of a retained catheter secondary to placement within the right proximal ureter. PMID:27144050

  18. 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.

  19. Ground plane insulating coating for proximity focused devices

    DOEpatents

    Power, Gary D.

    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.

  20. Groups as units of functional analysis, individuals as proximate mechanisms.

    PubMed

    Wilson, David Sloan

    2014-06-01

    Whenever selection operates at a given level of a multitier hierarchy, units at that level should become the object of functional analysis, and units at lower levels should be studied as proximate mechanisms. This intuition already exists for the study of genes in individuals, when individuals are the unit of selection. It is only beginning to be applied for the study of individuals in groups, when groups are the unit of selection. Smaldino's target article is an important step in this direction with an emphasis on human cultural evolution, but the same algorithm applies to all multilevel evolutionary processes.

  1. 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.

  2. Acute tumor lysis syndrome after proximal splenic artery embolization.

    PubMed

    Salsamendi, Jason T; Doshi, Mehul H; Gortes, Francisco J; Levi, Joe U; Narayanan, Govindarajan

    2016-06-01

    Preoperative splenic artery embolization for massive splenomegaly has been shown to reduce intraoperative hemorrhage during splenectomy. We describe a case of tumor lysis syndrome after proximal splenic artery embolization in a patient with advanced mantle cell lymphoma and splenic involvement. The patient presented initially with hyperkalemia two days after embolization that worsened during splenectomy. He was stabilized, but developed laboratory tumor lysis syndrome with renal failure and expired. High clinical suspicion of tumor lysis syndrome in this setting is advised. Treatment must be started early to avoid serious renal injury and death. Lastly, same day splenectomy and embolization should be considered to decrease the likelihood of developing tumor lysis syndrome. PMID:27257458

  3. An unusual presentation of hemophilia B: pseudotumor of proximal tibia.

    PubMed

    Mittal, Saurav; Arora, Sumit; Khanna, Shilpa; Maini, Lalit; Gautam, V K

    2011-07-01

    Hemophilia is one of the most common genetically inherited causes of bleeding disorders. The usual presentation is continuous bleeding from a wound. Very seldom, it presents as a pseudotumor of bone. When left untreated, it may induce compression and pressure necrosis of adjacent structures. Careful evaluation and a high index of suspicion are usually required to arrive at the correct diagnosis. In this article, we report the case of a 10-year-old boy with hemophilia B (Christmas disease) that presented as a pseudotumor producing a large defect in the proximal tibia.

  4. Proximity effects in a topological-insulator/Mott-insulator heterostructure

    NASA Astrophysics Data System (ADS)

    Ueda, Suguru; Kawakami, Norio; Sigrist, Manfred

    2013-04-01

    We investigate proximity effects in a correlated heterostructure of a two-dimensional Mott insulator (MI) and a topological insulator (TI) by employing inhomogeneous dynamical mean-field theory. We show that the edge state of the TI induces strongly renormalized midgap states inside the MI region, which still have a remnant of the helical energy spectrum. The penetration of low-energy electrons, which is controlled by the interface tunneling V, largely enhances the electron mass inside the MI and also splits a single Dirac cone at edge sites into the spatially separated two Dirac cones in the strong V region.

  5. Bilateral traumatic proximal humerus fractures managed by open reduction and internal fixation with locked plates.

    PubMed

    Jaiswal, Atin; Kachchhap, Naiman Deepak; Chaterjee, Rupak; Tanwar, Yashwant Singh; Habib, Masood; Singh, Satya Prakash

    2013-01-01

    Fractures of the proximal humerus are uncommon in young patients. Although bilateral fracture of proximal humerus itself is rare, association with epilepsy and electrocution is frequent. Only one case of traumatic bilateral proximal humerus fracture has been reported in the literature. We report a rare case of bilateral traumatic displaced proximal humerus fractures in a 40 years old male patient, which was treated by means of open reduction and internal fixation with proximal humerus locked pates on both sides and obtained a good functional outcome.

  6. 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

  7. Proximal tubule-specific glutamine synthetase deletion alters basal and acidosis-stimulated ammonia metabolism.

    PubMed

    Lee, Hyun-Wook; Osis, Gunars; Handlogten, Mary E; Lamers, Wouter H; Chaudhry, Farrukh A; Verlander, Jill W; Weiner, I David

    2016-06-01

    Glutamine synthetase (GS) catalyzes the recycling of NH4 (+) with glutamate to form glutamine. GS is highly expressed in the renal proximal tubule (PT), suggesting ammonia recycling via GS could decrease net ammoniagenesis and thereby limit ammonia available for net acid excretion. The purpose of the present study was to determine the role of PT GS in ammonia metabolism under basal conditions and during metabolic acidosis. We generated mice with PT-specific GS deletion (PT-GS-KO) using Cre-loxP techniques. Under basal conditions, PT-GS-KO increased urinary ammonia excretion significantly. Increased ammonia excretion occurred despite decreased expression of key proteins involved in renal ammonia generation. After the induction of metabolic acidosis, the ability to increase ammonia excretion was impaired significantly by PT-GS-KO. The blunted increase in ammonia excretion occurred despite greater expression of multiple components of ammonia generation, including SN1 (Slc38a3), phosphate-dependent glutaminase, phosphoenolpyruvate carboxykinase, and Na(+)-coupled electrogenic bicarbonate cotransporter. We conclude that 1) GS-mediated ammonia recycling in the PT contributes to both basal and acidosis-stimulated ammonia metabolism and 2) adaptive changes in other proteins involved in ammonia metabolism occur in response to PT-GS-KO and cause an underestimation of the role of PT GS expression.

  8. An Auditory Illusion of Proximity of the Source Induced by Sonic Crystals

    PubMed Central

    Spiousas, Ignacio; Etchemendy, Pablo E.; Vergara, Ramiro O.; Calcagno, Esteban R.; Eguia, Manuel C.

    2015-01-01

    In this work we report an illusion of proximity of a sound source created by a sonic crystal placed between the source and a listener. This effect seems, at first, paradoxical to naïve listeners since the sonic crystal is an obstacle formed by almost densely packed cylindrical scatterers. Even when the singular acoustical properties of these periodic composite materials have been studied extensively (including band gaps, deaf bands, negative refraction, and birrefringence), the possible perceptual effects remain unexplored. The illusion reported here is studied through acoustical measurements and a psychophysical experiment. The results of the acoustical measurements showed that, for a certain frequency range and region in space where the focusing phenomenon takes place, the sonic crystal induces substantial increases in binaural intensity, direct-to-reverberant energy ratio and interaural cross-correlation values, all cues involved in the auditory perception of distance. Consistently, the results of the psychophysical experiment revealed that the presence of the sonic crystal between the sound source and the listener produces a significant reduction of the perceived relative distance to the sound source. PMID:26222281

  9. The effects of colloid solutions on renal proximal tubular cells in vitro.

    PubMed

    Neuhaus, Winfried; Schick, Martin A; Bruno, Raphael R; Schneiker, Bianca; Förster, Carola Y; Roewer, Norbert; Wunder, Christian

    2012-02-01

    Renal failure is a common complication of critically ill patients. Colloids such as hydroxyethyl starch (HES), gelatin, or albumin are regularly used for intravascular volume resuscitation, but there are increasing reports about the nephrotoxic side effects of synthetic colloids in septic patients. Therefore, we investigated the influence of colloids (HES130/0.4 (Voluven®), gelatin (Gelafundin®), human albumin, and the crystalloid Sterofundin® ISO on cell viability of human proximal tubular (HK-2) cells. HK-2 cells were incubated with colloids (0.1%-4%) and with equivalent volumes of the crystalloid solution Sterofundin ISO. After 21 hours, cell viability of HK-2 cells was measured by EZ4U assay (dye XTT). Application of HES130/0.4 decreased cell viability significantly in a concentration-dependent manner (86.80% ± 10.79% by 0.5% HES down to 24.02% ± 4.27% by 4% HES). Human albumin (>1.25%) as well as gelatin (>1%) also showed deleterious effects on HK-2 cells. Interestingly, in lower concentrations, human albumin and the crystalloid solution Sterofundin ISO were cytoprotective in comparison with the NaCl control. In conclusion, synthetic and natural colloids showed a harmful impact on HK-2 cells in higher concentrations without any prior proinflammatory stimulus. HES130/0.4 exhibited the most distinctive harmful impact, whereas the application of crystalloid Sterofundin ISO revealed cytoprotective effects.

  10. 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.

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

    SciTech Connect

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

    2015-06-15

    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 μm 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. Effect of pressure blanching on sensory and proximate composition of peanut milk.

    PubMed

    Jain, Parul; Yadav, Deep Narayan; Rajput, Hradesh; Bhatt, Devendra Kumar

    2013-06-01

    Small scale process for the production of peanut milk was developed from M-522 variety of peanut. Three treatments i.e. traditional, 1% NaHCO3 soaking and pressure blanching (at 121 °C, 15 psi for 2, 3 and 5 mins) were given for the preparation of peanut milk. The milks so obtained were analyzed for chemical composition and also subjected to organoleptic evaluation using nine point hedonic scale by semi trained panel of judges. Peanut milk prepared by pressure blanching (at 121 °C, 15 psi for 3 min) was found most acceptable method. The proximate composition of the most acceptable peanut milk prepared by pressure blanching (at 121 °C, 15 psi for 3 min) was found to be moisture 88.22%, ash 0.16%, fat 1.65%, protein 3.27%, total solids 11.78%. Based on the results it was concluded that the pressure blanching was found most acceptable method for the preparation of peanut milk beverage although it had the negative effect on the protein and total solid extraction.

  13. 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.

  14. Pulse compression grating fabrication by diffractive proximity photolithography.

    PubMed

    Stuerzebecher, Lorenz; Fuchs, Frank; Harzendorf, Torsten; Zeitner, Uwe D

    2014-02-15

    We report about a newly devised throughput-scalable fabrication method for high-quality periodic submicron structures. The process is demonstrated for optical transmission gratings in fused silica with a period of 800 nm (1250  lines/mm) to be used in laser pulse compression. The technology is based on an innovative advancement of i-line proximity photolithography performed in a mask aligner. The aerial image is encoded in a rigorously optimized electron-beam-written three-level phase mask which is illuminated by an adapted multipole configuration of incidence angles. In comparison to conventional proximity lithography, the process enables a significantly higher resolution while maintaining a good depth of focus--in contrast to lithography based on direct Talbot-imaging. Details about the grating fabrication process and characterization of fabricated pulse compression grating wafers are presented. The gratings show a diffraction efficiency of 97% at a wavelength of 1030 nm and a wavefront error comparable to gratings fabricated by electron-beam lithography.

  15. Modulation of hydrophobic interactions by proximally immobilized ions.

    PubMed

    Ma, C Derek; Wang, Chenxuan; Acevedo-Vélez, Claribel; Gellman, Samuel H; Abbott, Nicholas L

    2015-01-15

    The structure of water near non-polar molecular fragments or surfaces mediates the hydrophobic interactions that underlie a broad range of interfacial, colloidal and biophysical phenomena. Substantial progress over the past decade has improved our understanding of hydrophobic interactions in simple model systems, but most biologically and technologically relevant structures contain non-polar domains in close proximity to polar and charged functional groups. Theories and simulations exploring such nanometre-scale chemical heterogeneity find it can have an important effect, but the influence of this heterogeneity on hydrophobic interactions has not been tested experimentally. Here we report chemical force microscopy measurements on alkyl-functionalized surfaces that reveal a dramatic change in the surfaces' hydrophobic interaction strengths on co-immobilization of amine or guanidine groups. Protonation of amine groups doubles the strength of hydrophobic interactions, and guanidinium groups eliminate measurable hydrophobic interactions in all pH ranges investigated. We see these divergent effects of proximally immobilized cations also in single-molecule measurements on conformationally stable β-peptides with non-polar subunits located one nanometre from either amine- or guanidine-bearing subunits. Our results demonstrate the importance of nanometre-scale chemical heterogeneity, with hydrophobicity not an intrinsic property of any given non-polar domain but strongly modulated by functional groups located as far away as one nanometre. The judicious placing of charged groups near hydrophobic domains thus provides a strategy for tuning hydrophobic driving forces to optimize molecular recognition or self-assembly processes.

  16. Cancer risk and residential proximity to cranberry cultivation in Massachusetts.

    PubMed Central

    Aschengrau, A; Ozonoff, D; Coogan, P; Vezina, R; Heeren, T; Zhang, Y

    1996-01-01

    OBJECTIVES: This study evaluated the relationship between cancer risk and residential proximity to cranberry cultivation. METHODS: A population-based case-control study was conducted. Cases, diagnosed during 1983 through 1986 among residents of the Upper Cape Cod area of Massachusetts, involved incident cancers of the lung (n = 252), breast (n = 265), colon-rectum (n = 326), bladder (n = 63), kidney (n = 35), pancreas (n = 37), and brain (n = 37), along with leukemia (n = 35). Control subjects were randomly selected from among telephone subscribers (n = 184), Medicare beneficiaries (n = 464), and deceased individuals (n = 723). RESULTS: No meaningful increases in risk were seen for any of the cancer sites except for the brain. When latency was considered, subjects who had ever lived within 2600 ft (780 m) of a cranberry bog had a twofold increased risk of brain cancer overall (95% confidence interval [CI] = 0.8, 4.9) and a 6.7-fold increased risk of astrocytoma (95% CI = 1.6, 27.8). CONCLUSIONS: Residential proximity to cranberry bog cultivation was not associated with seven of the eight cancers investigated; however, an association was observed with brain cancer, particularly astrocytoma. Larger, more detailed studies are necessary to elucidate this relationship. PMID:8806382

  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. 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

  19. Cell osmotic water permeability of isolated rabbit proximal convoluted tubules.

    PubMed

    Carpi-Medina, P; González, E; Whittembury, G

    1983-05-01

    Cell osmotic water permeability, Pcos, of the peritubular aspect of the proximal convoluted tubule (PCT) was measured from the time course of cell volume changes subsequent to the sudden imposition of an osmotic gradient, delta Cio, across the cell membrane of PCT that had been dissected and mounted in a chamber. The possibilities of artifact were minimized. The bath was vigorously stirred, the solutions could be 95% changed within 0.1 s, and small osmotic gradients (10-20 mosM) were used. Thus, the osmotically induced water flow was a linear function of delta Cio and the effect of the 70-microns-thick unstirred layers was negligible. In addition, data were extrapolated to delta Cio = 0. Pcos for PCT was 41.6 (+/- 3.5) X 10(-4) cm3 X s-1 X osM-1 per cm2 of peritubular basal area. The standing gradient osmotic theory for transcellular osmosis is incompatible with this value. Published values for Pcos of PST are 25.1 X 10(-4), and for the transepithelial permeability Peos values are 64 X 10(-4) for PCT and 94 X 10(-4) for PST, in the same units. These results indicate that there is room for paracellular water flow in both nephron segments and that the magnitude of the transcellular and paracellular water flows may vary from one segment of the proximal tubule to another. PMID:6846543

  20. A positioned +1 nucleosome enhances promoter-proximal pausing.

    PubMed

    Jimeno-González, Silvia; Ceballos-Chávez, María; Reyes, José C

    2015-03-31

    Chromatin distribution is not uniform along the human genome. In most genes there is a promoter-associated nucleosome free region (NFR) followed by an array of nucleosomes towards the gene body in which the first (+1) nucleosome is strongly positioned. The function of this characteristic chromatin distribution in transcription is not fully understood. Here we show in vivo that the +1 nucleosome plays a role in modulating RNA polymerase II (RNAPII) promoter-proximal pausing. When a +1 nucleosome is strongly positioned, elongating RNAPII has a tendency to stall at the promoter-proximal region, recruits more negative elongation factor (NELF) and produces less mRNA. The nucleosome-induced pause favors pre-mRNA quality control by promoting the addition of the cap to the nascent RNA. Moreover, the uncapped RNAs produced in the absence of a positioned nucleosome are degraded by the 5'-3' exonuclease XRN2. Interestingly, reducing the levels of the chromatin remodeler ISWI factor SNF2H decreases +1 nucleosome positioning and increases RNAPII pause release. This work demonstrates a function for +1 nucleosome in regulation of transcription elongation, pre-mRNA processing and gene expression.

  1. Parkinson's Disease Prevalence and Proximity to Agricultural Cultivated Fields.

    PubMed

    Yitshak Sade, Maayan; Zlotnik, Yair; Kloog, Itai; Novack, Victor; Peretz, Chava; Ifergane, Gal

    2015-01-01

    The risk for developing Parkinson's disease (PD) is a combination of multiple environmental and genetic factors. The Negev (Southern Israel) contains approximately 252.5 km(2) of agricultural cultivated fields (ACF). We aimed to estimate the prevalence and incidence of PD and to examine possible geographical clustering and associations with agricultural exposures. We screened all "Clalit" Health Services members in the Negev (70% of the population) between the years 2000 and 2012. Individual demographic, clinical, and medication prescription data were available. We used a refined medication tracer algorithm to identify PD patients. We used mixed Poisson models to calculate the smoothed standardized incidence rates (SIRs) for each locality. We identified ACF and calculate the size and distance of the fields from each locality. We identified 3,792 cases of PD. SIRs were higher than expected in Jewish rural localities (median SIR [95% CI]: 1.41 [1.28; 1.53] in 2001-2004, 1.62 [1.48; 1.76] in 2005-2008, and 1.57 [1.44; 1.80] in 2009-2012). Highest SIR was observed in localities located in proximity to large ACF (SIR 1.54, 95% CI 1.32; 1.79). In conclusion, in this population based study we found that PD SIRs were higher than expected in rural localities. Furthermore, it appears that proximity to ACF and the field size contribute to PD risk.

  2. Intramedullary screw fixation of proximal fifth metatarsal fractures in athletes

    PubMed Central

    Massada, Marta Maria Teixeira de Oliveira; Pereira, Manuel Alexandre Negrais Pinho Gonçalves; de Sousa, Ricardo Jorge Gomes; Costa, Paulo Guimarães; Massada, José Leandro da Rocha

    2012-01-01

    Objective The purpose of this study was to review the short- and long-term clinical and radiological results of intramedullary compression screw fixation of proximal fifth metatarsal fractures in athletes. Methods Eleven male and six female active patients with fifth metatarsal zone II and zone III fractures fixed with a 4.5-mm cannulated compression screw were evaluated by chart review, review of radiographs, and clinical evaluation. Fifteen of the patients were high-level athletes (soccer: n=11; basketball: n=1; track and field: n=3) and two were recreational-level athletes. Mean follow-up from surgery to evaluation was 54 (38-70) months. Results Mean time to healing as shown on radiographs and mean time to return to full activity after surgery were 7.3 and 7.5 weeks, respectively. All patients were able to return to their previous levels of activity. There were no reports of union delay, nonunion or refracture to date. Conclusion In our patients, cannulated screw fixation of proximal fifth metatarsal fractures was a reliable procedure with low morbidity associated that provided athletes a quick return to activity. Level of Evidence I, Case Series. PMID:24453614

  3. High-accuracy simulation-based optical proximity correction

    NASA Astrophysics Data System (ADS)

    Keck, Martin C.; Henkel, Thomas; Ziebold, Ralf; Crell, Christian; Thiele, J.÷rg

    2003-12-01

    In times of continuing aggressive shrinking of chip layouts a thorough understanding of the pattern transfer process from layout to silicon is indispensable. We analyzed the most prominent effects limiting the control of this process for a contact layer like process, printing 140nm features of variable length and different proximity using 248nm lithography. Deviations of the photo mask from the ideal layout, in particular mask off-target and corner rounding have been identified as clearly contributing to the printing behavior. In the next step, these deviations from ideal behavior have been incorporated into the optical proximity correction (OPC) modeling process. The degree of accuracy for describing experimental data by simulation, using an OPC model modified in that manner could be increased significantly. Further improvement in modeling the optical imaging process could be accomplished by taking into account lens aberrations of the exposure tool. This suggests a high potential to improve OPC by considering the effects mentioned, delivering a significant contribution to extending the application of OPC techniques beyond current limits.

  4. Group Problem Solving as a Zone of Proximal Development activity

    NASA Astrophysics Data System (ADS)

    Brewe, Eric

    2006-12-01

    Vygotsky described learning as a process, intertwined with development, which is strongly influenced by social interactions with others that are at differing developmental stages.i These interactions create a Zone of Proximal Development for each member of the interaction. Vygotsky’s notion of social constructivism is not only a theory of learning, but also of development. While teaching introductory physics in an interactive format, I have found manifestations of Vygotsky’s theory in my classroom. The source of evidence is a paired problem solution. A standard mechanics problem was solved by students in two classes as a homework assignment. Students handed in the homework and then solved the same problem in small groups. The solutions to both the group and individual problem were assessed by multiple reviewers. In many cases the group score was the same as the highest individual score in the group, but in some cases, the group score was higher than any individual score. For this poster, I will analyze the individual and group scores and focus on three groups solutions and video that provide evidence of learning through membership in a Zone of Proximal Development. Endnotes i L. Vygotsky -Mind and society: The development of higher mental processes. Cambridge, MA: Harvard University Press. (1978).

  5. Acid-base transport by the renal proximal tubule

    PubMed Central

    Skelton, Lara A.; Boron, Walter F.; Zhou, Yuehan

    2015-01-01

    Each day, the kidneys filter 180 L of blood plasma, equating to some 4,300 mmol of the major blood buffer, bicarbonate (HCO3−). The glomerular filtrate enters the lumen of the proximal tubule (PT), and the majority of filtered HCO3− is reclaimed along the early (S1) and convoluted (S2) portions of the PT in a manner coupled to the secretion of H+ into the lumen. The PT also uses the secreted H+ to titrate non-HCO3− buffers in the lumen, in the process creating “new HCO3−” for transport into the blood. Thus, the PT – along with more distal renal segments – is largely responsible for regulating plasma [HCO3−]. In this review we first focus on the milestone discoveries over the past 50+ years that define the mechanism and regulation of acid-base transport by the proximal tubule. Further on in the review, we will summarize research still in progress from our laboratory, work that addresses the problem of how the PT is able to finely adapt to acid–base disturbances by rapidly sensing changes in basolateral levels of HCO3− and CO2 (but not pH), and thereby to exert tight control over the acid–base composition of the blood plasma. PMID:21170887

  6. Designing and Applying Proximity-Dependent Hybridization Chain Reaction.

    PubMed

    Koos, Björn; Söderberg, Ola

    2016-01-01

    Proximity-dependent hybridization chain reaction (proxHCR) is a novel technique for detection of protein interaction, post-translational modifications (PTMs), or protein expression. The method is based upon antibodies targeting the proteins of interest that are covalently conjugated to DNA oligonucleotides, which enables the induction of a hybridization chain reaction (HCR) to generate a fluorescent signal visible under a microscope. In contrast to the in situ proximity ligation assay (in situ PLA), which is another method that utilizes antibody-DNA conjugates to detect protein interactions, proxHCR does not require enzymatic steps. This makes proxHCR an inexpensive alternative to in situ PLA. Another potential advantage might be that proxHCR could more readily be adapted for use in automated staining procedures and in point-of-care devices, as all reagents can be stored at room temperature. This unit describes how the oligonucleotide system for proxHCR can be designed and a protocol for how to perform proxHCR is presented. © 2016 by John Wiley & Sons, Inc.

  7. Vision-based proximity detection in retinal surgery.

    PubMed

    Richa, R; Balicki, M; Sznitman, R; Meisner, E; Taylor, R; Hager, G

    2012-08-01

    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, intraocular 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.

  8. ADAM17 substrate release in proximal tubule drives kidney fibrosis

    PubMed Central

    Kefaloyianni, Eirini; Muthu, Muthu Lakshmi; Kaeppler, Jakob; Sun, Xiaoming; Sabbisetti, Venkata; Chalaris, Athena; Rose-John, Stefan; Wong, Eitan; Sagi, Irit; Waikar, Sushrut S.; Rennke, Helmut; Bonventre, Joseph V.

    2016-01-01

    Kidney fibrosis following kidney injury is an unresolved health problem and causes significant morbidity and mortality worldwide. In a study into its molecular mechanism, we identified essential causative features. Acute or chronic kidney injury causes sustained elevation of a disintegrin and metalloprotease 17 (ADAM17); of its cleavage-activated proligand substrates, in particular of pro-TNFα and the EGFR ligand amphiregulin (pro-AREG); and of the substrates’ receptors. As a consequence, EGFR is persistently activated and triggers the synthesis and release of proinflammatory and profibrotic factors, resulting in macrophage/neutrophil ingress and fibrosis. ADAM17 hypomorphic mice, specific ADAM17 inhibitor–treated WT mice, or mice with inducible KO of ADAM17 in proximal tubule (Slc34a1-Cre) were significantly protected against these effects. In vitro, in proximal tubule cells, we show that AREG has unique profibrotic actions that are potentiated by TNFα-induced AREG cleavage. In vivo, in acute kidney injury (AKI) and chronic kidney disease (CKD, fibrosis) patients, soluble AREG is indeed highly upregulated in human urine, and both ADAM17 and AREG expression show strong positive correlation with fibrosis markers in related kidney biopsies. Our results indicate that targeting of the ADAM17 pathway represents a therapeutic target for human kidney fibrosis. PMID:27642633

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

    PubMed

    Kim, Dae In; Birendra, K C; Zhu, Wenhong; Motamedchaboki, Khatereh; Doye, Valérie; Roux, Kyle J

    2014-06-17

    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.

  10. QCL-based standoff and proximal chemical detectors

    NASA Astrophysics Data System (ADS)

    Dupuis, Julia R.; Hensley, Joel; Cosofret, Bogdan R.; Konno, Daisei; Mulhall, Phillip; Schmit, Thomas; Chang, Shing; Allen, Mark; Marinelli, William J.

    2016-05-01

    The development of two longwave infrared quantum cascade laser (QCL) based surface contaminant detection platforms supporting government programs will be discussed. The detection platforms utilize reflectance spectroscopy with application to optically thick and thin materials including solid and liquid phase chemical warfare agents, toxic industrial chemicals and materials, and explosives. Operation at standoff (10s of m) and proximal (1 m) ranges will be reviewed with consideration given to the spectral signatures contained in the specular and diffusely reflected components of the signal. The platforms comprise two variants: Variant 1 employs a spectrally tunable QCL source with a broadband imaging detector, and Variant 2 employs an ensemble of broadband QCLs with a spectrally selective detector. Each variant employs a version of the Adaptive Cosine Estimator for detection and discrimination in high clutter environments. Detection limits of 5 μg/cm2 have been achieved through speckle reduction methods enabling detector noise limited performance. Design considerations for QCL-based standoff and proximal surface contaminant detectors are discussed with specific emphasis on speckle-mitigated and detector noise limited performance sufficient for accurate detection and discrimination regardless of the surface coverage morphology or underlying surface reflectivity. Prototype sensors and developmental test results will be reviewed for a range of application scenarios. Future development and transition plans for the QCL-based surface detector platforms are discussed.

  11. ADAM17 substrate release in proximal tubule drives kidney fibrosis

    PubMed Central

    Kefaloyianni, Eirini; Muthu, Muthu Lakshmi; Kaeppler, Jakob; Sun, Xiaoming; Sabbisetti, Venkata; Chalaris, Athena; Rose-John, Stefan; Wong, Eitan; Sagi, Irit; Waikar, Sushrut S.; Rennke, Helmut; Humphreys, Benjamin D.; Bonventre, Joseph V.; Herrlich, Andreas

    2016-01-01

    Kidney fibrosis following kidney injury is an unresolved health problem and causes significant morbidity and mortality worldwide. In a study into its molecular mechanism, we identified essential causative features. Acute or chronic kidney injury causes sustained elevation of a disintegrin and metalloprotease 17 (ADAM17); of its cleavage-activated proligand substrates, in particular of pro-TNFα and the EGFR ligand amphiregulin (pro-AREG); and of the substrates’ receptors. As a consequence, EGFR is persistently activated and triggers the synthesis and release of proinflammatory and profibrotic factors, resulting in macrophage/neutrophil ingress and fibrosis. ADAM17 hypomorphic mice, specific ADAM17 inhibitor–treated WT mice, or mice with inducible KO of ADAM17 in proximal tubule (Slc34a1-Cre) were significantly protected against these effects. In vitro, in proximal tubule cells, we show that AREG has unique profibrotic actions that are potentiated by TNFα-induced AREG cleavage. In vivo, in acute kidney injury (AKI) and chronic kidney disease (CKD, fibrosis) patients, soluble AREG is indeed highly upregulated in human urine, and both ADAM17 and AREG expression show strong positive correlation with fibrosis markers in related kidney biopsies. Our results indicate that targeting of the ADAM17 pathway represents a therapeutic target for human kidney fibrosis.

  12. A method for sex estimation using the proximal femur.

    PubMed

    Curate, Francisco; Coelho, João; Gonçalves, David; Coelho, Catarina; Ferreira, Maria Teresa; Navega, David; Cunha, Eugénia

    2016-09-01

    The assessment of sex is crucial to the establishment of a biological profile of an unidentified skeletal individual. The best methods currently available for the sexual diagnosis of human skeletal remains generally rely on the presence of well-preserved pelvic bones, which is not always the case. Postcranial elements, including the femur, have been used to accurately estimate sex in skeletal remains from forensic and bioarcheological settings. In this study, we present an approach to estimate sex using two measurements (femoral neck width [FNW] and femoral neck axis length [FNAL]) of the proximal femur. FNW and FNAL were obtained in a training sample (114 females and 138 males) from the Luís Lopes Collection (National History Museum of Lisbon). Logistic regression and the C4.5 algorithm were used to develop models to predict sex in unknown individuals. Proposed cross-validated models correctly predicted sex in 82.5-85.7% of the cases. The models were also evaluated in a test sample (96 females and 96 males) from the Coimbra Identified Skeletal Collection (University of Coimbra), resulting in a sex allocation accuracy of 80.1-86.2%. This study supports the relative value of the proximal femur to estimate sex in skeletal remains, especially when other exceedingly dimorphic skeletal elements are not accessible for analysis. PMID:27373600

  13. Modulation of hydrophobic interactions by proximally immobilized ions

    NASA Astrophysics Data System (ADS)

    Ma, C. Derek; Wang, Chenxuan; Acevedo-Vélez, Claribel; Gellman, Samuel H.; Abbott, Nicholas L.

    2015-01-01

    The structure of water near non-polar molecular fragments or surfaces mediates the hydrophobic interactions that underlie a broad range of interfacial, colloidal and biophysical phenomena. Substantial progress over the past decade has improved our understanding of hydrophobic interactions in simple model systems, but most biologically and technologically relevant structures contain non-polar domains in close proximity to polar and charged functional groups. Theories and simulations exploring such nanometre-scale chemical heterogeneity find it can have an important effect, but the influence of this heterogeneity on hydrophobic interactions has not been tested experimentally. Here we report chemical force microscopy measurements on alkyl-functionalized surfaces that reveal a dramatic change in the surfaces' hydrophobic interaction strengths on co-immobilization of amine or guanidine groups. Protonation of amine groups doubles the strength of hydrophobic interactions, and guanidinium groups eliminate measurable hydrophobic interactions in all pH ranges investigated. We see these divergent effects of proximally immobilized cations also in single-molecule measurements on conformationally stable β-peptides with non-polar subunits located one nanometre from either amine- or guanidine-bearing subunits. Our results demonstrate the importance of nanometre-scale chemical heterogeneity, with hydrophobicity not an intrinsic property of any given non-polar domain but strongly modulated by functional groups located as far away as one nanometre. The judicious placing of charged groups near hydrophobic domains thus provides a strategy for tuning hydrophobic driving forces to optimize molecular recognition or self-assembly processes.

  14. A positioned +1 nucleosome enhances promoter-proximal pausing

    PubMed Central

    Jimeno-González, Silvia; Ceballos-Chávez, María; Reyes, José C.

    2015-01-01

    Chromatin distribution is not uniform along the human genome. In most genes there is a promoter-associated nucleosome free region (NFR) followed by an array of nucleosomes towards the gene body in which the first (+1) nucleosome is strongly positioned. The function of this characteristic chromatin distribution in transcription is not fully understood. Here we show in vivo that the +1 nucleosome plays a role in modulating RNA polymerase II (RNAPII) promoter-proximal pausing. When a +1 nucleosome is strongly positioned, elongating RNAPII has a tendency to stall at the promoter-proximal region, recruits more negative elongation factor (NELF) and produces less mRNA. The nucleosome-induced pause favors pre-mRNA quality control by promoting the addition of the cap to the nascent RNA. Moreover, the uncapped RNAs produced in the absence of a positioned nucleosome are degraded by the 5′-3′ exonuclease XRN2. Interestingly, reducing the levels of the chromatin remodeler ISWI factor SNF2H decreases +1 nucleosome positioning and increases RNAPII pause release. This work demonstrates a function for +1 nucleosome in regulation of transcription elongation, pre-mRNA processing and gene expression. PMID:25735750

  15. Preparation of the proximal femur in cementless total hip revision.

    PubMed

    Mallory, T H

    1988-10-01

    With an increased incidence of revision for the failed cemented total hip arthroplasty, techniques of revision surgery need meticulous attention to detail. Although the causes of the failed cemented total hip arthroplasty are many, they tend to follow characteristic patterns. The proximal femur can be exposed through an extensive muscle split incision, which offers a complete circumferential view of the femur. The cement removal is enhanced by controlled perforation using high-speed drills. Classification of bony deficits of the proximal femur can be divided into Type I, including intact cortex and medullary content; Type II, in which there is intact cortex but deficient medullary content; and Type III, in which deficits of both the cortex and medullary canal are present. Prosthetic selection is based on residual bone stock. In general, cementless fixation is advocated, with distal fixation using long-stem devices. Augmentation of bone deficits requires the use of segmental prosthetic replacement or fresh-frozen allografts. One hundred sixty patients were followed for two to six years. Satisfactory results have occurred in over 90% of the patients; better results are anticipated in patients with minimal bone deficits. Aseptic loosening requiring rerevision has occurred in 5% of the patient population. Understanding the dynamics of failure and the residual bone deficits allows one to manage the failed cemented total hip arthroplasty with greater efficiency and predictability. PMID:3416541

  16. A method for sex estimation using the proximal femur.

    PubMed

    Curate, Francisco; Coelho, João; Gonçalves, David; Coelho, Catarina; Ferreira, Maria Teresa; Navega, David; Cunha, Eugénia

    2016-09-01

    The assessment of sex is crucial to the establishment of a biological profile of an unidentified skeletal individual. The best methods currently available for the sexual diagnosis of human skeletal remains generally rely on the presence of well-preserved pelvic bones, which is not always the case. Postcranial elements, including the femur, have been used to accurately estimate sex in skeletal remains from forensic and bioarcheological settings. In this study, we present an approach to estimate sex using two measurements (femoral neck width [FNW] and femoral neck axis length [FNAL]) of the proximal femur. FNW and FNAL were obtained in a training sample (114 females and 138 males) from the Luís Lopes Collection (National History Museum of Lisbon). Logistic regression and the C4.5 algorithm were used to develop models to predict sex in unknown individuals. Proposed cross-validated models correctly predicted sex in 82.5-85.7% of the cases. The models were also evaluated in a test sample (96 females and 96 males) from the Coimbra Identified Skeletal Collection (University of Coimbra), resulting in a sex allocation accuracy of 80.1-86.2%. This study supports the relative value of the proximal femur to estimate sex in skeletal remains, especially when other exceedingly dimorphic skeletal elements are not accessible for analysis.

  17. Scintillation proximity assay (SPA) technology to study biomolecular interactions.

    PubMed

    Cook, Neil; Harris, Alison; Hopkins, Alison; Hughes, Kelvin

    2002-05-01

    Scintillation proximity assay (SPA) is a versatile homogeneous technique for radioactive assays which eliminates the need for separation steps. In SPA, scintillant is incorporated into small fluomicrospheres. These microspheres or "beads" are constructed in such a way as to bind specific molecules. If a radioactive molecule is bound to the bead, it is brought into close enough proximity that it can stimulate the scintillant contained within to emit light. Otherwise, the unbound radioactivity is too distant, the energy released is dissipated before reaching the bead, and these disintegrations are not detected. In this unit, the application of SPA technology to measuring protein-protein interactions, Src Homology 2 (SH2) and 3 (SH3) domain binding to specific peptide sequences, and receptor-ligand interactions are described. Three other protocols discuss the application of SPA technology to cell-adhesion-molecule interactions, protein-DNA interactions, and radioimmunoassays. In addition, protocols are given for preparation of SK-N-MC cells and cell membranes. PMID:18429228

  18. Two Proximal Skin Electrodes — A Respiration Rate Body Sensor

    PubMed Central

    Trobec, Roman; Rashkovska, Aleksandra; Avbelj, Viktor

    2012-01-01

    We propose a new body sensor for extracting the respiration rate based on the amplitude changes in the body surface potential differences between two proximal body electrodes. The sensor could be designed as a plaster-like reusable unit that can be easily fixed onto the surface of the body. It could be equipped either with a sufficiently large memory for storing the measured data or with a low-power radio system that can transmit the measured data to a gateway for further processing. We explore the influence of the sensor's position on the quality of the extracted results using multi-channel ECG measurements and considering all the pairs of two neighboring electrodes as potential respiration-rate sensors. The analysis of the clinical measurements, which also include reference thermistor-based respiration signals, shows that the proposed approach is a viable option for monitoring the respiration frequency and for a rough classification of breathing types. The obtained results were evaluated on a wireless prototype of a respiration body sensor. We indicate the best positions for the respiration body sensor and prove that a single sensor for body surface potential difference on proximal skin electrodes can be used for combined measurements of respiratory and cardiac activities. PMID:23202022

  19. Spatial mismatch between the Na+ flux and spike initiation in axon initial segment.

    PubMed

    Baranauskas, Gytis; David, Yaron; Fleidervish, Ilya A

    2013-03-01

    It is widely believed that, in cortical pyramidal cells, action potentials (APs) initiate in the distal portion of axon initial segment (AIS) because that is where Na(+) channel density is highest. To investigate the relationship between the density of Na(+) channels and the spatiotemporal pattern of AP initiation, we simultaneously recorded Na(+) flux and action currents along the proximal axonal length. We found that functional Na(+) channel density is approximately four times lower in the AP trigger zone than in the middle of the AIS, where it is highest. Computational analysis of AP initiation revealed a paradoxical mismatch between the AP threshold and Na(+) channel density, which could be explained by the lopsided capacitive load imposed on the proximal end of the AIS by the somatodendritic compartment. Favorable conditions for AP initiation are therefore achieved in the distal AIS portion, close to the edge of myelin, where the current source-load ratio is highest. Our findings suggest that cable properties play a central role in determining where the AP starts, such that small plastic changes in the local AIS Na(+) channel density could have a large influence on neuronal excitability as a whole.

  20. Effect of different cooking methods on proximate and mineral composition of striped snakehead fish (Channa striatus, Bloch).

    PubMed

    Marimuthu, K; Thilaga, M; Kathiresan, S; Xavier, R; Mas, R H M H

    2012-06-01

    The effects of different cooking methods (boiling, baking, frying and grilling) on proximate and mineral composition of snakehead fish were investigated. The mean content of moisture, protein, fat and ash of raw fish was found to be 77.2 ± 2.39, 13.9 ± 2.89, 5.9 ± 0.45 and 0.77 ± 0.12% respectively. The changes in the amount of protein and fat were found to be significantly higher in frying and grilling fish. The ash content increased significantly whereas that of the minerals (Na, K, Ca, Mg, Fe, Zn and Mn) was not affected in all cooking methods. Increased in Cu contents and decreased in P contents were observed in all cooking methods except grilling. In the present study, the grilling method of cooking is found to be the best for healthy eating.

  1. Differential regulation of the renal sodium-phosphate cotransporters NaPi-IIa, NaPi-IIc, and PiT-2 in dietary potassium deficiency.

    PubMed

    Breusegem, Sophia Y; Takahashi, Hideaki; Giral-Arnal, Hector; Wang, Xiaoxin; Jiang, Tao; Verlander, Jill W; Wilson, Paul; Miyazaki-Anzai, Shinobu; Sutherland, Eileen; Caldas, Yupanqui; Blaine, Judith T; Segawa, Hiroko; Miyamoto, Ken-ichi; Barry, Nicholas P; Levi, Moshe

    2009-08-01

    Dietary potassium (K) deficiency is accompanied by phosphaturia and decreased renal brush border membrane (BBM) vesicle sodium (Na)-dependent phosphate (P(i)) transport activity. Our laboratory previously showed that K deficiency in rats leads to increased abundance in the proximal tubule BBM of the apical Na-P(i) cotransporter NaPi-IIa, but that the activity, diffusion, and clustering of NaPi-IIa could be modulated by the altered lipid composition of the K-deficient BBM (Zajicek HK, Wang H, Puttaparthi K, Halaihel N, Markovich D, Shayman J, Beliveau R, Wilson P, Rogers T, Levi M. Kidney Int 60: 694-704, 2001; Inoue M, Digman MA, Cheng M, Breusegem SY, Halaihel N, Sorribas V, Mantulin WW, Gratton E, Barry NP, Levi M. J Biol Chem 279: 49160-49171, 2004). Here we investigated the role of the renal Na-P(i) cotransporters NaPi-IIc and PiT-2 in K deficiency. Using Western blotting, immunofluorescence, and quantitative real-time PCR, we found that, in rats and in mice, K deficiency is associated with a dramatic decrease in the NaPi-IIc protein abundance in proximal tubular BBM and in NaPi-IIc mRNA. In addition, we documented the presence of a third Na-coupled P(i) transporter in the renal BBM, PiT-2, whose abundance is also decreased by dietary K deficiency in rats and in mice. Finally, electron microscopy showed subcellular redistribution of NaPi-IIc in K deficiency: in control rats, NaPi-IIc immunolabel was primarily in BBM microvilli, whereas, in K-deficient rats, NaPi-IIc BBM label was reduced, and immunolabel was prevalent in cytoplasmic vesicles. In summary, our results demonstrate that decreases in BBM abundance of the phosphate transporter NaPi-IIc and also PiT-2 might contribute to the phosphaturia of dietary K deficiency, and that the three renal BBM phosphate transporters characterized so far can be differentially regulated by dietary perturbations.

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

    SciTech Connect

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

    1990-10-01

    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.

  3. Childhood leukemia and residential proximity to industrial and urban sites

    SciTech Connect

    García-Pérez, Javier; López-Abente, Gonzalo; Gómez-Barroso, Diana; Morales-Piga, Antonio; Pardo Romaguera, Elena; Tamayo, Ibon; Fernández-Navarro, Pablo; and others

    2015-07-15

    Background: Few risk factors for the childhood leukemia are well established. While a small fraction of cases of childhood leukemia might be partially attributable to some diseases or ionizing radiation exposure, the role of industrial and urban pollution also needs to be assessed. Objectives: To ascertain the possible effect of residential proximity to both industrial and urban areas on childhood leukemia, taking into account industrial groups and toxic substances released. Methods: We conducted a population-based case–control study of childhood leukemia in Spain, covering 638 incident cases gathered from the Spanish Registry of Childhood Tumors and for those Autonomous Regions with 100% coverage (period 1990-2011), and 13,188 controls, individually matched by year of birth, sex, and autonomous region of residence. Distances were computed from the respective subject’s residences to the 1068 industries and the 157 urban areas with ≥10,000 inhabitants, located in the study area. Using logistic regression, odds ratios (ORs) and 95% confidence intervals (95%CIs) for categories of distance to industrial and urban pollution sources were calculated, with adjustment for matching variables. Results: Excess risk of childhood leukemia was observed for children living near (≤2.5 km) industries (OR=1.31; 95%CI=1.03–1.67) – particularly glass and mineral fibers (OR=2.42; 95%CI=1.49–3.92), surface treatment using organic solvents (OR=1.87; 95%CI=1.24–2.83), galvanization (OR=1.86; 95%CI=1.07–3.21), production and processing of metals (OR=1.69; 95%CI=1.22–2.34), and surface treatment of metals (OR=1.62; 95%CI=1.22–2.15) – , and urban areas (OR=1.36; 95%CI=1.02–1.80). Conclusions: Our study furnishes some evidence that living in the proximity of industrial and urban sites may be a risk factor for childhood leukemia. - Highlights: • We studied proximity to both industrial and urban sites on childhood leukemia. • We conducted a case–control study in

  4. Pragmatic RCT on the Efficacy of Proximal Caries Infiltration.

    PubMed

    Meyer-Lueckel, H; Balbach, A; Schikowsky, C; Bitter, K; Paris, S

    2016-05-01

    Proximal caries infiltration has been shown to be efficacious in hampering caries lesion progression when performed by dentists working in a university setting. The aim of this randomized split-mouth, placebo-controlled clinical trial was to assess the efficacy of resin infiltration of proximal caries lesions being performed by several dentists in private practices, in combination with individualized oral hygiene plus noninvasive measures compared with these alone. In this study, 87 children and young adults (with 238 pairs of proximal caries lesions radiographically extending into the inner half of the enamel [E2] or the outer third of the dentin [D1]) were randomly allocated to either 1 of 2 treatments. Test lesions were infiltrated, and a mock treatment was performed in control lesions by 5 German private practitioners. All patients received instructions for a noncariogenic diet, flossing and fluoridation, and individualized noninvasive interventions. The primary outcome was radiographic lesion progression (pairwise comparison) evaluated independently by 2 evaluators who were blinded to treatment allocation. After approximately 10 mo (mean ± SD 307 ± 43 d), 92 of 148 lesion pairs in 24 of 38 treated patients who were at high caries risk could be re-evaluated clinically as well as radiographically using individualized bitewing holders, as at baseline; 186 of 204 lesion pairs in 70 of 77 patients (35 of 38 high-risk patients) could be evaluated after 18 mo (mean 542 ± 110 d). No unwanted effects were observed. After 10 mo, progression was recorded in 2 of 92 test lesions (2%) and in 22 of 92 control lesions (24%) (P= 0.001, McNemar/Obuchowski test; relative risk reduction, 91; 95% confidence interval, 62%-98%). After 18 mo, lesion progression was recorded in all included patients in 10 of 186 test lesions (5%) and in 58 of 186 control lesions (31%) (P< 0.001; relative risk reduction, 83; 95% confidence interval, 67%-91%). Thus, resin infiltration seems to be

  5. 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

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

    SciTech Connect

    Kinsella, J.; Sacktor, B.

    1985-06-01

    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.

  7. 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.

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

    PubMed Central

    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

    2012-01-01

    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

  9. 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.

  10. Extracorporeal shockwave therapy for chronic proximal plantar fasciitis.

    PubMed

    Strash, Walter W; Perez, Richard R

    2002-10-01

    Although much enthusiasm surrounds applying extracorporeal shock wave therapy for various musculoskeletal conditions, its effects are not well understood and warrant continued study. Certain body tissues or organs may be damaged either acutely or chronically by ESWT; however, it is unequivocal that lung tissue may be damaged. It is theorized that neovascularization is responsible for improvement in symptoms of plantar fasciitis. Neovascularization is the direct effect of macrophage stimulation through cytokines. ESWT has effects at the cellular level--does it interfere with metabolic activity or enhance it? The noninvasive nature and minimal complications of appropriately applied ESWT are its primary advantages. Symptoms may continue to improve for three weeks to six months after treatment; the effects of shock wave therapy seem to be time dependent. ESWT is an effective form of treatment for proximal insertional plantar fasciitis after exhaustive, conservative forms of treatment have failed.

  11. Residential proximity to environmental hazards and adverse health outcomes.

    PubMed

    Brender, Jean D; Maantay, Juliana A; Chakraborty, Jayajit

    2011-12-01

    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

  12. Fundamental Proximity Effects in Focused electron Beam Induced Deposition

    SciTech Connect

    Plank, Harald; Smith, Daryl; Haber, Thomas; Rack, Philip D; Hofer, Ferdinand

    2012-01-01

    Fundamental proximity effects for electron beam induced deposition processes on nonflat surfaces were studied experimentally and via simulation. Two specific effects were elucidated and exploited to considerably increase the volumetric growth rate of this nanoscale direct write method: (1) increasing the scanning electron pitch to the scale of the lateral electron straggle increased the volumetric growth rate by 250% by enhancing the effective forward scattered, backscattered, and secondary electron coefficients as well as by strong recollection effects of adjacent features; and (2) strategic patterning sequences are introduced to reduce precursor depletion effects which increase volumetric growth rates by more than 90%, demonstrating the strong influence of patterning parameters on the final performance of this powerful direct write technique.

  13. Detection of Protein SUMOylation In Situ by Proximity Ligation Assays.

    PubMed

    Sahin, Umut; Jollivet, Florence; Berthier, Caroline; de Thé, Hugues; Lallemand-Breitenbach, Valérie

    2016-01-01

    Sumoylation is a posttranslational process essential for life and concerns a growing number of crucial proteins. Understanding the influence of this phenomenon on individual proteins or on cellular pathways in which they function has become an intense area of research. A critical step in studying protein sumoylation is to detect sumoylated forms of a particular protein. This has proven to be a challenging task for a number of reasons, especially in the case of endogenous proteins and in vivo studies or when studying rare cells such as stem cells. Proximity ligation assays that allow detection of closely interacting protein partners can be adapted for initial detection of endogenous sumoylation or ubiquitination in a rapid, ultrasensitive, and cheap manner. In addition, modified forms of a given protein can be detected in situ in various cellular compartments. Finally, the flexibility of this technique may allow rapid screening of drugs and stress signals that may modulate protein sumoylation. PMID:27631803

  14. Endogenous opioids: a proximate reward mechanism for kin selection?

    PubMed

    D'Amato, F R; Pavone, F

    1993-07-01

    The kin selection theory predicts that individuals would behave differently toward one another, depending on their genetic relatedness. Proximate mechanisms have been postulated to exist helping the individual to discriminate what is good or bad for him. Opioids have been discovered to be involved in the mediation of reinforcement, in particular they underlay social emotion. In this study it is shown that pain sensitivity decreased in male mice interacting with siblings following 2 months of separation; this analgesic response was antagonized by naloxone administration. Interaction with unknown and unrelated subjects did not change the nociceptive threshold. These results suggest that interacting with kin is an adaptive situation reinforced, at the neural level, by the release of endogenous opioids.

  15. Xanthogranulomatous Osteomyelitis of Proximal Femur Masquerading as Benign Bone Tumor.

    PubMed

    Singh, Shailendra; Batra, Sahil; Maini, Lalit; Gautam, Virender Kumar

    2015-08-01

    We describe a case of xanthogranulomatous osteomyelitis (XO) of the proximal femur in a 65-year-old woman who presented with pain of 6 months' duration in the right hip. Plain radiographs showed a lytic well-defined lesion in the right peritrochanteric region suggestive of a benign neoplastic etiology. The gross and histopathologic examination of the curettage specimen was consistent with XO. Xanthogranulomatous osteomyelitis is a rare chronic inflammatory process that is characterized by the presence of a large number of lipid-containing macrophages with an admixture of lymphocytes, plasma cells, and neutrophils. Gross and radiologic examination of this entity can mimic malignancy, and differentiation should be confirmed by histopathologic evaluation. To the best of our knowledge, XO of the femur has not been reported in the English-language literature. The rarity of this condition and its resemblance to bone tumors form the basis of this case report. PMID:26251942

  16. Orion Rendezvous, Proximity Operations, and Docking Design and Analysis

    NASA Technical Reports Server (NTRS)

    D'Souza, Christopher; Hanak, F. Chad; Spehar, Pete; Clark, Fred D.; Jackson, Mark

    2007-01-01

    The Orion vehicle will be required to perform rendezvous, proximity operations, and docking with the International Space Station (ISS) and the Earth Departure Stage (EDS)/Lunar Landing Vehicle (LLV) stack in Low Earth Orbit (LEO) as well as with the Lunar Landing Vehicle in Low Lunar Orbit (LLO). The RPOD system, which consists of sensors, actuators, and software is being designed to be flexible and robust enough to perform RPOD with different vehicles in different environments. This paper will describe the design and the analysis which has been performed to date to allow the vehicle to perform its mission. Since the RPOD design touches on many areas such as sensors selection and placement, trajectory design, navigation performance, and effector performance, it is inherently a systems design problem. This paper will address each of these issues in order to demonstrate how the Orion RPOD has been designed to accommodate and meet all the requirements levied on the system.

  17. 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.

  18. 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.

  19. Rendezvous, proximity operations and capture quality function deployment report

    NASA Technical Reports Server (NTRS)

    Lamkin, Stephen L. (Editor)

    1991-01-01

    Rendezvous, Proximity Operations, and Capture (RPOC) is a missions operations area which is extremely important to present and future space initiatives and must be well planned and coordinated. To support this, a study team was formed to identify a specific plan of action using the Quality Function Deployment (QFD) process. This team was composed of members from a wide spectrum of engineering and operations organizations which are involved in the RPOC technology area. The key to this study's success is an understanding of the needs of potential programmatic customers and the technology base available for system implementation. To this end, the study team conducted interviews with a variety of near term and future programmatic customers and technology development sponsors. The QFD activity led to a thorough understanding of the needs of these customers in the RPOC area, as well as the relative importance of these needs.

  20. Extraction of spatial proximity patterns by concept generalization

    SciTech Connect

    Knorr, E.M.; Ng, R.T.

    1996-12-31

    We study the spatial data mining problem of how to extract a special type of proximity relationship-namely that of distinguishing two clusters of points based on the types of their neighboring features. The points in the clusters may represent houses on a map, and the features may represent spatial entities such as schools, parks, golf courses, etc. Classes of features are organized into concept hierarchies. We develop algorithm GenDis which uses concept generalization to identify the distinguishing features or concepts which serve as discriminators. Furthermore, we study the issue of which discriminators are {open_quotes}better{close_quotes} than others by introducing the notion of maximal discriminators, and by using a ranking system to quantitatively weigh maximal discriminators from different concept hierarchies.

  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. Antegrade versus retrograde intramedullary nailing of proximal third femur fractures.

    PubMed

    Kuhn, Kevin M; Ali, Ashley; Boudreau, John A; Cannada, Lisa K; Watson, John T

    2013-01-01

    The purpose of this study is to retrospectively review the results of proximal third femur fractures treated with retrograde nailing (RGN) and compare those results to a cohort from the same period treated with antegrade nailing (AGN). Adult patients with femur fractures within 10 cm of the lesser trochanter who were treated with intramedullary nails were reviewed. Two groups, patients treated with AGN (n = 35) and RGN (n = 34), were compiled. Demographic information, comorbidities, associated injuries, radiographic outcomes, complications, and secondary procedures were compared. There were two malunions in the AGN group and three in the RGN group. The AGN group had two nonunions while the RGN group had one. Subgroup analysis demonstrated that a higher body mass index (BMI) (p = .011) and a higher AO/OTA fracture classification (p = .019) were the only factors predictive of malunion. Regardless of starting point, there were no differences between groups in the number of secondary procedures, nonunions, malunions, or time until union.

  3. Automobile proximity and indoor residential concentrations of BTEX and MTBE

    SciTech Connect

    Corsi, Dr. Richard; Morandi, Dr. Maria; Siegel, Dr. Jeffrey; Hun, Diana E

    2011-01-01

    Attached garages have been identified as important sources of indoor residential air pollution. However, the literature lacks information on how the proximity of cars to the living area affects indoor concentrations of gasoline-related compounds, and the origin of these pollutants. We analyzed data from the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study and evaluated 114 residences with cars in an attached garage, detached garage or carport, or without cars. Results indicate that homes with cars in attached garages were affected the most. Concentrations in homes with cars in detached garages and residences without cars were similar. The contribution from gasoline-related sources to indoor benzene and MTBE concentrations appeared to be dominated by car exhaust, or a combination of tailpipe and gasoline vapor emissions. Residing in a home with an attached garage could lead to benzene exposures ten times higher than exposures from commuting in heavy traffic.

  4. Complications following dislocations of the proximal interphalangeal joint.

    PubMed

    Mangelson, John J; Stern, Peter J; Abzug, Joshua M; Chang, James; Osterman, A Lee

    2014-01-01

    Dorsal fracture-dislocations of the proximal interphalangeal joint are challenging injuries to treat and are associated with many complications. The determination of stability is crucial to appropriate management. Stable injuries can usually be treated nonsurgically, whereas unstable injuries typically require surgical stabilization. Many surgical techniques have been used, including extension block pinning, volar plate arthroplasty, open reduction and internal fixation, external fixation, and hemihamate autografting. Because stiffness and flexion contracture are frequent complications, every effort should be made to initiate early motion while maintaining concentric reduction. Other complications include redislocation, chronic swelling, swan neck and coronal plane deformities, and pin tract infections. Assessing injury characteristics, including chronicity, the percentage of articular surface fractured, and the degree of comminution, and understanding complications will help in determining the most appropriate treatment. Chronic dislocations and those injuries in which painful arthritis develops can be successfully treated with salvage procedures, including arthroplasty and arthrodesis. PMID:24720300

  5. A Simplified Lateral Hinge Approach to the Proximal Interphalangeal Joint.

    PubMed

    Bain, Gregory I; McGuire, Duncan T; McGrath, Aleksandra M

    2015-09-01

    Proximal interphalangeal joint replacement is an effective treatment for painful arthritis affecting the joint. However, the complication rate is relatively high, with many of these complications related to soft-tissue imbalance or instability. Volar, dorsal, and lateral approaches have all been described with varying results. We describe a new simplified lateral hinge approach that splits the collateral ligament to provide adequate exposure of the joint. Following insertion of the prosthesis the collateral ligament is simply repaired, side-to-side, which stabilizes the joint. As the central slip, opposite collateral ligament, flexor and extensor tendons have not been violated, early active mobilization without splinting is possible, and the risk of instability, swan-neck, and boutonniere deformity are reduced. The indications, contraindications, surgical technique, and rehabilitation protocol are described. PMID:26230632

  6. Sensitive detection of aggregated prion protein via proximity ligation.

    PubMed

    Hammond, Maria; Wik, Lotta; Deslys, Jean-Philippe; Comoy, Emmanuel; Linné, Tommy; Landegren, Ulf; Kamali-Moghaddam, Masood

    2014-01-01

    The DNA assisted solid-phase proximity ligation assay (SP-PLA) provides a unique opportunity to specifically detect prion protein (PrP) aggregates by investigating the collocation of 3 or more copies of the specific protein. We have developed an SP-PLA that can detect PrP aggregates in brain homogenates from infected hamsters even after a 10(7)-fold dilution. In contrast, brain homogenate from uninfected animals did not generate a detectable signal at 100-fold higher concentration. Using either of the 2 monoclonal anti-PrP antibodies, 3F4 and 6H4, we successfully detected low concentrations of aggregated PrP. The presented results provide a proof of concept that this method might be an interesting tool in the development of diagnostic approaches of prion diseases.

  7. Scanning Tunneling Spectroscopy of Proximity Superconductivity in Epitaxial Multilayer Graphene

    PubMed Central

    Natterer, Fabian D.; Ha, Jeonghoon; Baek, Hongwoo; Zhang, Duming; Cullen, William; Zhitenev, Nikolai B.; Kuk, Young; Stroscio, Joseph A.

    2016-01-01

    We report on spatial measurements of the superconducting proximity effect in epitaxial graphene induced by a graphene-superconductor interface. Superconducting aluminum films were grown on epitaxial multilayer graphene on SiC. The aluminum films were discontinuous with networks of trenches in the film morphology reaching down to exposed graphene terraces. Scanning tunneling spectra measured on the graphene terraces show a clear decay of the superconducting energy gap with increasing separation from the graphene-aluminum edges. The spectra were well described by Bardeen-Cooper-Schrieffer (BCS) theory. The decay length for the superconducting energy gap in graphene was determined to be greater than 400 nm. Deviations in the exponentially decaying energy gap were also observed on a much smaller length scale of tens of nanometers. PMID:27088134

  8. Detection of Protein SUMOylation In Situ by Proximity Ligation Assays.

    PubMed

    Sahin, Umut; Jollivet, Florence; Berthier, Caroline; de Thé, Hugues; Lallemand-Breitenbach, Valérie

    2016-01-01

    Sumoylation is a posttranslational process essential for life and concerns a growing number of crucial proteins. Understanding the influence of this phenomenon on individual proteins or on cellular pathways in which they function has become an intense area of research. A critical step in studying protein sumoylation is to detect sumoylated forms of a particular protein. This has proven to be a challenging task for a number of reasons, especially in the case of endogenous proteins and in vivo studies or when studying rare cells such as stem cells. Proximity ligation assays that allow detection of closely interacting protein partners can be adapted for initial detection of endogenous sumoylation or ubiquitination in a rapid, ultrasensitive, and cheap manner. In addition, modified forms of a given protein can be detected in situ in various cellular compartments. Finally, the flexibility of this technique may allow rapid screening of drugs and stress signals that may modulate protein sumoylation.

  9. Anomalous magnetization reversal due to proximity effect of antiphase boundaries

    NASA Astrophysics Data System (ADS)

    Sofin, R. G. S.; Wu, Han-Chun; Shvets, I. V.

    2011-12-01

    Here we report anomalous double switching hysteresis loop and high coercivity (˜0.1 T) in Fe3O4(110) thin films. Our analytical model based on spin chains confined within small antiphase boundary domains (APBDs) suggests a significant proximity effect of antiferromagnetic antiphase boundaries (APBs). Furthermore, the calculated domain size (D) follows the well-known scaling relation D=Ct. The results suggest that the interface exchange coupling between neighboring magnetic domains through antiferromagnetic APBs is responsible for the double switching hysteresis. Our findings could help advance the studies of anomalous properties of magnetic materials originating from growth defects. This effect can be utilized for the tunability of exchange bias in devices.

  10. Analytic Description of Superconducting-Ferromagnetic Proximity Systems

    NASA Astrophysics Data System (ADS)

    Baker, Thomas E.; Icreverzi, Ovidiu E.; Moke, Adam K.; Bill, Andreas

    2013-03-01

    We present the exact analytic solution of the Usadel equations for a proximity system made of a superconductor and a ferromagnet in the wide dirty limit, including spin-flip scattering. The solution was found by mathematical analogy to the Jacobi elliptic function description of a classical mechanics system known as the bead on a hoop. We highlight the parallels between the two systems and present an analysis of the solution with special attention to long rage triplet effects and the inverse Fulde-Ferrell-Larkin-Ovchinnikov state. We determine the Josephson critical current and the variation of the critical temperature with spin-flip scattering. We gratefully acknowledge the support of the National Science Foundation (DMR-0907242), the CSU Long Beach Graduate Research Fellowship, The Research Corporation, and the Army Research Laboratory.

  11. Benchmark of numerical versus analytical proximity curve calculations

    NASA Astrophysics Data System (ADS)

    Köhle, Roderick; Bodendorf, Christof; Hoppe, Wolfgang

    2006-03-01

    For the technology development of microlithography various optical simulation tools are established as a planning and development tool. Depending on the application, various numerical approximation schemes are used to tradeoff accuracy versus speed. Determining the correct numerical setting is often a tricky task as it is a compromise between these two contrary properties. In our study, we compare the numerical accuracy of two optical simulators, Solid-E as a representative for simulators for technology development and Mentor Calibre as design-for-manufacturing and optical proximity correction (OPC) tool. Calibre uses a coherent kernel approximation for performing fast simulations. As a measure for the simulation accuracy, we use the root-mean-square error criterion of a linearity curve compared to an analytical reference simulation.

  12. Variation in the ADH1B proximal promoter affects expression.

    PubMed

    Pochareddy, Sirisha; Edenberg, Howard J

    2011-05-30

    The primary pathway of metabolism of dietary alcohol is via its oxidation in liver by alcohol dehydrogenases (ADH). Differences in the ADH enzyme activity or levels of enzyme present could affect the risk for alcoholism. Regulatory variations have been shown to affect the promoter activity and thereby affect the risk for alcoholism. In this study the functional effects of the two SNPs (rs1159918 and rs1229982) in the proximal promoter region of ADH1B that were associated with alcoholism were explored. We examined the effects of five naturally occurring haplotypes on the promoter activity. We observed that a C to A change at rs1229982 increased promoter activity 1.4-fold.

  13. Factors affecting minority population proximity to hazardous facilities

    SciTech Connect

    Nieves, L.A.; Nieves, A.L. |

    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.

  14. Proximity fingerprint of s{plus_minus} superconductivity.

    SciTech Connect

    Koshelev, A. E.; Stanev, V.

    2011-01-01

    We suggest a straightforward and unambiguous test to identify possible opposite signs of the superconducting order parameter in different bands proposed for iron-based superconductors (s{sub {+-}}-state). We consider the proximity effect in a weakly coupled sandwich composed of a s{sub {+-}}-superconductor and a thin layer of the s-wave superconductor. In such system the s-wave order parameter is coupled differently with different s{sub {+-}}-gaps and it typically aligns with one of these gaps. This forces the other s{sub {+-}}-gap to be anti-aligned with the s-wave gap. In such situation the aligned band induces a peak in the s-wave density of states (DoS), while the anti-aligned band induces a dip. Observation of such contact-induced negative feature in the s-wave DoS would provide a definite proof for s{sub {+-}}-superconductivity.

  15. Solute-Solvent Energetics Based on Proximal Distribution Functions.

    PubMed

    Ou, Shu-Ching; Pettitt, B Montgomery

    2016-08-25

    We consider the hydration structure and thermodynamic energetics of solutes in aqueous solution. On the basis of the dominant local correlation between the solvent and the chemical nature of the solute atoms, proximal distribution functions (pDF) can be used to quantitatively estimate the hydration pattern of the macromolecules. We extended this technique to study the solute-solvent energetics including the van der Waals terms representing excluded volume and tested the method with butane and propanol. Our results indicate that the pDF-reconstruction algorithm can reproduce van der Waals solute-solvent interaction energies to useful kilocalorie per mole accuracy. We subsequently computed polyalanine-water interaction energies for a variety of conformers, which also showed agreement with the simulated values. PMID:27095487

  16. Rendezvous, proximity operations and capture quality function deployment report

    NASA Astrophysics Data System (ADS)

    Lamkin, Stephen L.

    1991-12-01

    Rendezvous, Proximity Operations, and Capture (RPOC) is a missions operations area which is extremely important to present and future space initiatives and must be well planned and coordinated. To support this, a study team was formed to identify a specific plan of action using the Quality Function Deployment (QFD) process. This team was composed of members from a wide spectrum of engineering and operations organizations which are involved in the RPOC technology area. The key to this study's success is an understanding of the needs of potential programmatic customers and the technology base available for system implementation. To this end, the study team conducted interviews with a variety of near term and future programmatic customers and technology development sponsors. The QFD activity led to a thorough understanding of the needs of these customers in the RPOC area, as well as the relative importance of these needs.

  17. Genome-wide proximal promoter analysis and interpretation.

    PubMed

    Guruceaga, Elizabeth; Segura, Victor; Corrales, Fernando J; Rubio, Angel

    2010-01-01

    High-throughput gene expression technologies based on DNA microarrays allow the examination of biological systems. However, the interpretation of the complex molecular descriptions generated by these approaches is still challenging. The development of new methodologies to identify common regulatory mechanisms involved in the control of the expression of a set of co-expressed genes might enhance our capacity to extract functional information from genomic data sets. In this chapter, we describe a method that integrates different sources of information: gene expression data, genome sequence information, described transcription factor binding sites (TFBSs), functional information, and bibliographic data. The starting point of the analysis is the extraction of promoter sequences from a whole genome and the detection of TFBSs in each gene promoter. This information allows the identification of enriched TFBSs in the proximal promoter of differentially expressed genes. The functional and bibliographic interpretation of the results improves our biological insight into the regulatory mechanisms involved in a microarray experiment. PMID:19957149

  18. Photoresponse experiments on NbN proximized nanostructures

    NASA Astrophysics Data System (ADS)

    Pepe, G. P.; Parlato, L.; Pagliarulo, V.; Marrocco, N.; De Lisio, C.; Peluso, G.; Barone, A.; Taino, T.; Myoren, H.; Casaburi, A.; Ejrnaes, M.; Cristiano, R.

    2010-06-01

    Among superconducting materials used in developing high performance nanowire detectors, NbN demonstrated to have unique characteristics in terms of fast response time, quantum efficiency and photon-number resolving capability. We investigated the role of proximity effect on superconducting NbN thin films covered by a weak ferromagnetic NiCu thin layer. Hetero-structures NbN/NiCu have been deposited by DC magnetron sputtering on MgO substrates without any heating. Characterization in terms of morphological, transport, and ultra-fast optical properties has been done. Superconducting nanowires with meander-type geometries (48 micron lengths and <500 nm widths) have been designed and fabricated. Preliminary results concerning their photoresponse to 1550nm laser irradiation are presented.

  19. A Simplified Lateral Hinge Approach to the Proximal Interphalangeal Joint.

    PubMed

    Bain, Gregory I; McGuire, Duncan T; McGrath, Aleksandra M

    2015-09-01

    Proximal interphalangeal joint replacement is an effective treatment for painful arthritis affecting the joint. However, the complication rate is relatively high, with many of these complications related to soft-tissue imbalance or instability. Volar, dorsal, and lateral approaches have all been described with varying results. We describe a new simplified lateral hinge approach that splits the collateral ligament to provide adequate exposure of the joint. Following insertion of the prosthesis the collateral ligament is simply repaired, side-to-side, which stabilizes the joint. As the central slip, opposite collateral ligament, flexor and extensor tendons have not been violated, early active mobilization without splinting is possible, and the risk of instability, swan-neck, and boutonniere deformity are reduced. The indications, contraindications, surgical technique, and rehabilitation protocol are described.

  20. 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.

  1. Proximity Effects in Nb/InAs Quantum Well Structures

    NASA Astrophysics Data System (ADS)

    Eckhause, T. A.; Gwinn, E. G.; Thomas, M.; Kroemer, H.

    1997-03-01

    InAs has been widely used as a weak link in superconductor-semiconductor-superconductor junctions.(E. L. Yuh et al., Surf. Sci. 361/362), 315 (1996) Most theoretical treatments of such structures assume that proximity to InAs does not reduce the Nb gap. To test this assumption we have fabricated structures with an ultra-thin layer of Nb on the exposed surface of the InAs quantum well. After removing the cap layer from the μ = 210,000 cm/V\\cdot s, ns = 5.5 x 10^12cm-2 InAs quantum well, Nb films of ~ 100Åthickness are deposited simultaneously on the 150Åquantum well and on a semi-insulating GaAs substrate (both surfaces are sputter cleaned prior to deposition). We cap the Nb with a ~100ÅSi layer of to prevent oxidation.(S.I. Park and T.H. Geballe, Physica B 135), 108 (1985) After processing, the sheet resistances just above Tc are 23.5Ω and 67Ω in the Nb film and quantum well, respectively. We observed a ~ 0.2K lower critical temperature in the Nb/InAs sample. As the Nb films are otherwise nominally identical and the proximity effect is known to suppress the critical temperature of thin films, this suppression in Tc may be due to the reduction of the gap in Nb. Supported by NSF grant DMR-93-14899

  2. Detecting Proximal Secondary Caries Lesions: A Cost-effectiveness Analysis.

    PubMed

    Schwendicke, F; Brouwer, F; Paris, S; Stolpe, M

    2016-02-01

    When choosing detection methods for secondary caries lesions, dentists need to weigh sensitivity, allowing early initiation of retreatments to avoid lesion progression, against specificity, aiming to reduce risks of false-positive diagnoses and invasive overtreatments. We assessed the cost-effectiveness of different detection methods for proximal secondary lesions using Monte Carlo microsimulations. A vital permanent molar with an occlusal-proximal restoration was simulated over the lifetime of an initially 20-y-old. Three methods were compared: biannual tactile detection, radiographic detection every 2 y, and biannual laser fluorescence detection. Methods were employed either on their own or in pairwise combinations at sensitive and specific thresholds estimated with systematically collected data. A mixed public-private payer perspective in the context of German health care was applied. Effectiveness was calculated as years of tooth retention. Net-benefit analyses were used to evaluate cost-effectiveness acceptability at different willingness-to-pay thresholds. Radiographic detection verified by tactile assessment (both at specific thresholds) was least costly (mean, 1,060 euros) but had limited effectiveness (mean retention time, 50 y). The most effective but also more costly combination was laser fluorescence detection verified by radiography, again at specific thresholds (1157 euros, 53 y, acceptable if willingness to pay >32 euro/y). In the majority of simulations, not combining detection methods or applying them at sensitive thresholds was less effective and more costly. Net benefits were not greatly altered by applying different discounting rates or using different baseline prevalence of secondary lesions. Current detection methods for secondary lesions should best be used in combination, not on their own, at specific thresholds to avoid false-positive diagnoses leading to costly and invasive overtreatment. The relevant characteristics, such as predictive

  3. New Autophagy Reporter Mice Reveal Dynamics of Proximal Tubular Autophagy

    PubMed Central

    Li, Ling; Wang, Zhao V.

    2014-01-01

    The accumulation of autophagosomes in postischemic kidneys may be renoprotective, but whether this accumulation results from the induction of autophagy or from obstruction within the autophagic process is unknown. Utilizing the differential pH sensitivities of red fluorescent protein (RFP; pKa 4.5) and enhanced green fluorescent protein (EGFP; pKa 5.9), we generated CAG-RFP-EGFP-LC3 mice to distinguish early autophagic vacuoles from autolysosomes. In vitro and in vivo studies confirmed that in response to nutrient deprivation, renal epithelial cells in CAG-RFP-EGFP-LC3 mice produce autophagic vacuoles expressing RFP and EGFP puncta. EGFP fluorescence diminished substantially in the acidic environment of the autolysosomes, whereas bright RFP signals remained. Under normal conditions, nephrons expressed few EGFP and RFP puncta, but ischemia-reperfusion injury (IRI) led to dynamic changes in the proximal tubules, with increased numbers of RFP and EGFP puncta that peaked at 1 day after IRI. The number of EGFP puncta returned to control levels at 3 days after IRI, whereas the high levels of RFP puncta persisted, indicating autophagy initiation at day 1 and autophagosome clearance during renal recovery at day 3. Notably, proliferation decreased in cells containing RFP puncta, suggesting that autophagic cells are less likely to divide for tubular repair. Furthermore, 87% of proximal tubular cells with activated mechanistic target of rapamycin (mTOR), which prevents autophagy, contained no RFP puncta. Conversely, inhibition of mTOR complex 1 induced RFP and EGFP expression and decreased cell proliferation. In summary, our results highlight the dynamic regulation of autophagy in postischemic kidneys and suggest a role of mTOR in autophagy resolution during renal repair. PMID:24179166

  4. Process proximity correction using an automated software tool

    NASA Astrophysics Data System (ADS)

    Maurer, Wilhelm; Dolainsky, Christoph; Thiele, Joerg; Friedrich, Christoph M.; Karakatsanis, Paul

    1998-06-01

    The pattern transfer process from the chip layout data to the structures on the finished wafer consists of many process steps. Although desired, none of these steps is linear in all aspects of the pattern transfer. Approaching the process limits due to the ever-shrinking linewidth, the non- linearities of the pattern transfer clearly show up. This means, that one cannot continue the practice to summarize all process influences into one bias between the data used for mask making and the final chip structure. The correction of process non-linearities is a necessity. This correction is usually called optical proximity correction (OPC), although not all effects intended for correction are of optical origin and/or not all these are effects of the neighborhood. We therefore propose to use the term PPC (process proximity correction). This paper reports our experiences with the application of OPTISSIMO, a software tool developed to perform automatically OPC/PPC for full chip designs. First, we provide a definition of PPC, which in our view has to correct all non- linearities of the pattern transfer process from layout data to the final electrically measured structures. Then, the strategy of the OPC/PPC tool OPTISSIMO, a software package to perform PPC based on process simulation, is discussed. We focus on the data handling strategy and on the process modeling of the tool under evaluation. It is shown, that full chip OPC/PPC is practicable using a well-designed hierarchy management system combined with a pattern library. Finally, it is demonstrated, that a model-based OPC/PPC tool is by definition a process simulation tool, that is able to perform all simulation tasks (like defect printability) at reasonable accuracy.

  5. Surgical Treatment of Pathological Fractures Occurring at the Proximal Femur

    PubMed Central

    Choy, Won-Sik; Lee, Sang Ki; Yang, Dae Suk; Jeung, Sang Wook; Choi, Han Gyul; Park, Hyun Jong

    2015-01-01

    Purpose To analyze the results of surgical treatment for pathological fractures at the proximal femur. Materials and Methods Nineteen patients with a pathological fracture were included. The mean age was 65.7 years old. The patients comprised 8 males and 11 females. Primary tumors, types of pathological fractures, surgical procedures, and postoperative complications were recorded. Musculoskeletal Tumor Society (MSTS) functional score was used for functional evaluation. A Kaplan-Meier survival analysis was used to determine survival rate. Results The primary malignancies were 6 cases of breast cancer, 3 cases of lung cancer, 3 cases of renal cell carcinoma, 2 cases of cholangiocarcinoma, 2 cases of hepatocellular carcinoma, 1 case of esophageal cancer, 1 case of colon cancer, and 1 case of ovarian cancer. Pathological fractures included 8 cases of pertrochanteric fractures and 11 cases of subtrochanteric fractures. Intramedullary nailing was performed in 10 cases, and joint replacement surgery was performed in 9 cases. Postoperative complications included local recurrence in 1 case, infection in 1 case, and nail breakage in 1 case. The mean postoperative MSTS score was 21. The mean survival period was 10.6 months. Patient survival rates were 42.1% after 6 months, 26.3% after 12 months, and 10.5% after 24 months. Conclusion Surgical treatment of pathological fractures at the proximal femur provided early ambulation, and excellent pain relief. The surgery was well tolerated emotionally. Surgery is necessary for improving the quality of life in such patients; however, more cases of pathological fractures in these regions should be subjected to detailed analysis. PMID:25683996

  6. Tree mortality following partial harvests is determined by skidding proximity.

    PubMed

    Thorpe, H C; Thomas, S C; Caspersen, J P

    2008-10-01

    Recently developed structural retention harvesting strategies aim to improve habitat and ecological services provided by managed forest stands by better emulating natural disturbances. The potential for elevated mortality of residual trees following such harvests remains a critical concern for forest managers, and may present a barrier to more widespread implementation of the approach. We used a harvest chronosequence combined with dendrochronological techniques and an individual-based neighborhood analysis to examine the rate and time course of residual-tree mortality in the first decade following operational partial "structural retention" harvests in the boreal forest of Ontario, Canada. In the first year after harvest, residual-tree mortality peaked at 12.6 times the preharvest rate. Subsequently, mortality declined rapidly and approached preharvest levels within 10 years. Proximity to skid trails was the most important predictor both of windthrow and standing death, which contributed roughly equally to total postharvest mortality. Local exposure further increased windthrow risk, while crowding enhanced the risk of standing mortality. Ten years after harvest, an average of 10.5% of residual trees had died as a result of elevated postharvest mortality. Predicted cumulative elevated mortality in the first decade after harvest ranged from 2.4% to 37% of residual trees across the observed gradient of skid trail proximity, indicating that postharvest mortality will remain at or below acceptable rates only if skidding impacts are minimized. These results represent an important step toward understanding how elevated mortality may influence stand dynamics and habitat supply following moderate-severity disturbances such as partial harvests, insect outbreaks, and windstorms. PMID:18839761

  7. 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

  8. Identification of functionally distinct Na-HCO3 co-transporters in colon.

    PubMed

    Barmeyer, Christian; Ye, Jeff Huaqing; Soroka, Carol; Geibel, Peter; Hingsammer, Lukas M; Weitgasser, Laurence; Atway, Danny; Geibel, John P; Binder, Henry J; Rajendran, Vazhaikkurichi M

    2013-01-01

    Na-HCO3 cotransport (NBC) regulates intracellular pH (pHi) and HCO3 secretion in rat colon. NBC has been characterized as a 5,5'-diisothiocyanato-2-2'-stilbene (DIDS)-sensitive transporter in several tissues, while the colonic NBC is sensitive to both amiloride and DIDS. In addition, the colonic NBC has been identified as critical for pHi regulation as it is activated by intravesicular acid pH. Molecular studies have identified several characteristically distinct NBC isoforms [i.e. electrogenic (NBCe) and electroneutral (NBCn)] that exhibit tissue specific expression. This study was initiated to establish the molecular identity and specific function of NBC isoforms in rat colon. Northern blot and reverse transcriptase PCR (RT-PCR) analyses revealed that electrogenic NBCe1B or NBCe1C (NBCe1B/C) isoform is predominantly expressed in proximal colon, while electroneutral NBCn1C or NBCn1D (NBCn1C/D) is expressed in both proximal and distal colon. Functional analyses revealed that amiloride-insensitive, electrogenic, pH gradient-dependent NBC activity is present only in basolateral membranes of proximal colon. In contrast, amiloride-sensitive, electroneutral, [H(+)]-dependent NBC activity is present in both proximal and distal colon. Both electrogenic and electroneutral NBC activities are saturable processes with an apparent Km for Na of 7.3 and 4.3 mM, respectively; and are DIDS-sensitive with apparent Ki of 8.9 and 263.8 µM, respectively. In addition to Na-H exchanger isoform-1 (NHE1), pHi acidification is regulated by a HCO3-dependent mechanism that is HOE694-insensitive in colonic crypt glands. We conclude from these data that electroneutral, amiloride-sensitive NBC is encoded by NBCn1C/D and is present in both proximal and distal colon, while NBCe1B/C encodes electrogenic, amiloride-insensitive Na-HCO3 cotransport in proximal colon. We also conclude that NBCn1C/D regulates HCO3-dependent HOE694-insensitive Na-HCO3 cotransport and plays a critical role in p

  9. Osteoblast maturation occurs in overlapping proximal-distal compartments during fin regeneration in zebrafish.

    PubMed

    Brown, Andrew M; Fisher, Shannon; Iovine, M Kathryn

    2009-11-01

    During fin regeneration, osteoblasts must continually differentiate for outgrowth of the bony fin rays. Bone maturity increases in a distal-proximal manner, and osteoblast maturation can be detected similarly when following gene expression. We find that early markers for osteoblast differentiation are expressed in a discrete domain at the distal end of the fin, just proximal to the adjacent germinal compartment of dividing cells. Matrix genes, required at later stages developmentally, are expressed in a population of cells proximally to the early genes. A marker for mature osteoblasts is expressed in cells further proximal. These domains of gene expression are partially overlapping, perhaps revealing additional levels of osteoblast maturity. We suggest a model for growth where new cells are continually added to the distal-most osteoblast compartment, while osteoblasts in more proximal locations differentiate, thus translating developmental time to location on the proximal-distal axis. PMID:19842180

  10. Analysis of Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol

    NASA Technical Reports Server (NTRS)

    Woo, Simon S.

    2011-01-01

    To synchronize clocks between spacecraft in proximity, the Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol has been proposed. PITS is based on the NTP Interleaved On-Wire Protocol and is capable of being adapted and integrated into CCSDS Proximity-1 Space Link Protocol with minimal modifications. In this work, we will discuss the correctness and liveness of PITS. Further, we analyze and evaluate the performance of time synchronization latency with various channel error rates in different PITS operational modes.

  11. A dual-mode proximity sensor with integrated capacitive and temperature sensing units

    NASA Astrophysics Data System (ADS)

    Qiu, Shihua; Huang, Ying; He, Xiaoyue; Sun, Zhiguang; Liu, Ping; Liu, Caixia

    2015-10-01

    The proximity sensor is one of the most important devices in the field of robot application. It can accurately provide the proximity information to assistant robots to interact with human beings and the external environment safely. In this paper, we have proposed and demonstrated a dual-mode proximity sensor composed of capacitive and resistive sensing units. We defined the capacitive type proximity sensor perceiving the proximity information as C-mode and the resistive type proximity sensor detecting as R-mode. Graphene nanoplatelets (GNPs) were chosen as the R-mode sensing material because of its high performance. The dual-mode proximity sensor presents the following features: (1) the sensing distance of the dual-mode proximity sensor has been enlarged compared with the single capacitive proximity sensor in the same geometrical pattern; (2) experiments have verified that the proposed sensor can sense the proximity information of different materials; (3) the proximity sensing capability of the sensor has been improved by two modes perceive collaboratively, for a plastic block at a temperature of 60 °C: the R-mode will perceive the proximity information when the distance d between the sensor and object is 6.0-17.0 mm and the C-mode will do that when their interval is 0-2.0 mm additionally two modes will work together when the distance is 2.0-6.0 mm. These features indicate our transducer is very valuable in skin-like sensing applications.

  12. Characteristics analysis of polarization module on optical proximity effect

    NASA Astrophysics Data System (ADS)

    Park, Chanha; Hong, Jongkyun; Yang, Kiho; Theeuwes, Thomas; Gautier, Frederic; Min, Young-Hong; Chen, Alek; Yang, Hyunjo; Yim, Donggyu; Kim, Jinwoong

    2007-03-01

    In hyper NA system, specific illumination combined with polarization can be used as one of major RET techniques. Polarization at high NA dry system is also regarded as important technology to bring improvement of very low k1 process. The benefits of polarization on repeated structure are very well known. However we also need to understand the effect on random pattern in peripheral region to adopt polarization technology successfully into real devices. Memory device such as DRAM and NAND Flash has repeated cell structure and also loose pattern in peripheral region. In this study two kinds of polarization function will be applied to real memory devices and the polarization behavior on various patterns in peripheral circuit will be analyzed through actual printing process using 6% attenuated PSM at ArF high NA dry system. The printed result will be compared on random patterns through in-line metrology tool and process guideline including OPC treatment will be discussed based on this study, especially with regard to ID bias.

  13. Theory, Practice, and the "Zone of Proximal Development" in Soviet Psychoeducational Research.

    ERIC Educational Resources Information Center

    Wozniak, R. H.

    1980-01-01

    Philosphical principles provide the context for the Soviets' psychological theory (in particular, the "zone of proximal development" concept); this theory then shapes psychoeducational practice. (GDC)

  14. E4orf1 Enhances Glucose Uptake Independent of Proximal Insulin Signaling

    PubMed Central

    Na, Ha-Na; Hegde, Vijay; Dubuisson, Olga; Dhurandhar, Nikhil V.

    2016-01-01

    Impaired proximal insulin signaling is often present in diabetes. Hence, approaches to enhance glucose disposal independent of proximal insulin signaling are desirable. Evidence indicates that Adenovirus-derived E4orf1 protein may offer such an approach. This study determined if E4orf1 improves insulin sensitivity and downregulates proximal insulin signaling in vivo and enhances cellular glucose uptake independent of proximal insulin signaling in vitro. High fat fed mice were injected with a retrovirus plasmid expressing E4orf1, or a null vector. E4orf1 significantly improved insulin sensitivity in response to a glucose load. Yet, their proximal insulin signaling in fat depots was impaired, as indicated by reduced tyrosine phosphorylation of insulin receptor (IR), and significantly increased abundance of ectonucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1). In 3T3-L1 pre-adipocytes E4orf1 expression impaired proximal insulin signaling. Whereas, treatment with rosiglitazone reduced ENPP1 abundance. Unaffected by IR-KD (insulin receptor knockdown) with siRNA, E4orf1 significantly up-regulated distal insulin signaling pathway and enhanced cellular glucose uptake. In vivo, E4orf1 impairs proximal insulin signaling in fat depots yet improves glycemic control. This is probably explained by the ability of E4orf1 to promote cellular glucose uptake independent of proximal insulin signaling. E4orf1 may provide a therapeutic template to enhance glucose disposal in the presence of impaired proximal insulin signaling. PMID:27537838

  15. E4orf1 Enhances Glucose Uptake Independent of Proximal Insulin Signaling.

    PubMed

    Na, Ha-Na; Hegde, Vijay; Dubuisson, Olga; Dhurandhar, Nikhil V

    2016-01-01

    Impaired proximal insulin signaling is often present in diabetes. Hence, approaches to enhance glucose disposal independent of proximal insulin signaling are desirable. Evidence indicates that Adenovirus-derived E4orf1 protein may offer such an approach. This study determined if E4orf1 improves insulin sensitivity and downregulates proximal insulin signaling in vivo and enhances cellular glucose uptake independent of proximal insulin signaling in vitro. High fat fed mice were injected with a retrovirus plasmid expressing E4orf1, or a null vector. E4orf1 significantly improved insulin sensitivity in response to a glucose load. Yet, their proximal insulin signaling in fat depots was impaired, as indicated by reduced tyrosine phosphorylation of insulin receptor (IR), and significantly increased abundance of ectonucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1). In 3T3-L1 pre-adipocytes E4orf1 expression impaired proximal insulin signaling. Whereas, treatment with rosiglitazone reduced ENPP1 abundance. Unaffected by IR-KD (insulin receptor knockdown) with siRNA, E4orf1 significantly up-regulated distal insulin signaling pathway and enhanced cellular glucose uptake. In vivo, E4orf1 impairs proximal insulin signaling in fat depots yet improves glycemic control. This is probably explained by the ability of E4orf1 to promote cellular glucose uptake independent of proximal insulin signaling. E4orf1 may provide a therapeutic template to enhance glucose disposal in the presence of impaired proximal insulin signaling. PMID:27537838

  16. Appraisal and evolution of hydrochemical processes from proximity basalt and granite areas of Deccan Volcanic Province (DVP) in India

    NASA Astrophysics Data System (ADS)

    Sonkamble, Sahebrao; Sahya, Ashalata; Mondal, N. C.; Harikumar, P.

    2012-05-01

    SummaryThis paper deals with a systematic hydrochemical study carried out at proximity basalt and granite areas of Deccan Volcanic Province (DVP) in India to assess groundwater quality and evaluate the hydrochemical processes. A total of 40 groundwater samples were collected equally from these areas and analyzed. Results showed that the groundwaters rich in alkaline earth in the basalt and alkali rich element in the granite. The dominancy of cations was observed as Ca2+ > Mg2+ > Na+ > K+ in the basalt and Na+ > Mg2+ > K+ > Ca2+ in the granite, whereas anions as HCO3->Cl>SO42- and Cl>HCO3->SO42-, respectively. Hydrochemical processes were identified with the helps of ion exchange, carbonate weathering and dissolution, multiple ionic ratios, and silicate weathering, which shown the predominance of carbonate, dolomite, calcite and silicate (anorthite) weathering in basalt, but in granite, silicate (alkali feldspar) weathering was dominated. Factor analysis also showed that there were multiple processes acting on groundwaters, were separated from the main cluster. Salinity, Sodium Absorption Ratio (SAR), Soluble Sodium Percentage (SSP), Residual Sodium Carbonate (RSC), Kelley's Ratio (KR) and Permeability Index (PI) in well samples showed that groundwater in basalt was more suitable for irrigation purposes. Further, a digital elevation model (DEM) was generated using Global mapper (8.0 version) software, which aided to decipher the thickness of basalt trap, and vertical transition zone of basaltic (trap) and granitic (basement) aquifer at this DVP comprising with the well depths and groundwater chemistry.

  17. Proximal Blade Twist Feedback Control for Heliogyro Solar Sails

    NASA Astrophysics Data System (ADS)

    Smith, Sarah Mitchell

    mode is on the order of 0.005%, meaning there is almost no inherent damping in the blade. Next, the proximal blade twist feedback control design was successful in overcoming friction in the root actuator and added damping to the blade. The damping ratio for the lowest frequency torsional mode was increased from 0.001% to 0.09%, which is a significant amount for a heliogyro spacecraft. Finally, the camera sensor used for the proximal differential twist measurement proved to be feasible and quantization from these measurements only decreased the damping ratio to 0.075%. This research provides the first indication that a physically realizable blade root controller can deal with friction in an effective way, thus taking a step towards advancing the technology readiness level of the heliogyro spacecraft.

  18. Niche restriction in parasites: proximate and ultimate causes.

    PubMed

    Rohde, K

    1994-01-01

    Hutchinson's (1957) definition of an ecological niche as a multidimensional hypervolume determined by a number of physical and biotic variables is adopted. The number of niche dimensions is very great, but as a working hypothesis it is assumed that a few are sufficient to characterize the niche of a parasite species to a high degree of accuracy. They are host species, microhabitat(s), macrohabitat(s), geographical range, sex and age of host, season, food and hyperparasites. Methods to measure niche width, in particular specificity indices, are discussed, and some examples of niche restriction are described. Proximate and ultimate causes of niche restriction are discussed, mainly using marine parasites as examples. Among proximate causes of one niche dimension, host specificity, are ecological factors restricting exposure to infection to certain host species; host-specific chemical factors that induce hatching, direct infective stages to a host and bring about settlement of a parasite; factors that lead to mortality in or on the wrong host; morphological adaptations that guarantee survival in or on the 'correct' host; and availability of suitable hosts. Many factors are likely to be responsible for microhabitat specificity, but have been little studied, except for some physiological and morphological adaptations to particular microhabitats. Macrohabitats and geographical range may be determined by the distribution of intermediate hosts and certain food items, and by a variety of chemical and physical factors. Hosts of different sexes may differ in feeding habits and the composition of the skin, and thus acquire parasites differentially. Hosts of different age may be differentially infected due to accumulation of parasites with age, loss of parasites due to developing resistance (or immunity), and different size and feeding habits. Among ultimate causes of niche restriction and segregation are avoidance of competition, predation and hyperparasites; facilitation of

  19. Treatment of proximal fifth metatarsal bone fractures in athletes.

    PubMed

    Japjec, M; Starešinić, M; Starjački, M; Žgaljardić, I; Štivičić, J; Šebečić, B

    2015-11-01

    Proximal fifth metatarsal (V MT) bone fractures are common injuries that are a major diagnostic and therapeutic challenge. Lawrence and Botte considered different treatment options and the possibility of recovery and divided these fractures into three different regions: tuberosity avulsion fractures (zone I), acute fractures of the metaphysis at the level of the intermetatarsal junction (zone II) and proximal diaphysis stress fracture (zone III). A total of 42 athletes with fracture of the V MT bone in zone II and III were treated in our institution during a 6-year period. All patients were offered surgical treatment, but nine patients refused surgery. Thus, the patients were divided into two groups: group 1 comprised 33 patients who underwent an intramedullary screw fixation operation under regional anaesthesia immediately after the fracture was diagnosed; group 2 contained the remaining nine patients who had refused surgery and received conservative therapy with non-weight-bearing short-leg casts or orthosis. Follow-up ranged from 6 to 24 months. All fractures healed in group 1: healing occurred within 8 weeks in 26 patients and was prolonged to 16 to 18 weeks in four patients. In group 2, fractures healed in four patients but did not heal in five patients even after 6 months. Four of the five patients in whom the fracture did not heal required subsequent osteosynthesis because they had constant problems that caused absence from sport. After the operation, their fractures healed in an average of 10 weeks. One patient decided not to undergo the operation due to the absence of subjective symptoms. Three patients in group 1 who started intensive training sustained a refracture and underwent re-operation in which osteosynthesis was performed with a stronger screw. The fractures then healed again. Treatment results were evaluated radiologically and clinically using the Modified Foot Score. Results in group 1 were significantly better than those in group 2 and there

  20. Transepithelial osmolality differences, hydraulic conductivities, and volume absorption in the proximal tubule.

    PubMed

    Schafer, J A

    1990-01-01

    The weight of current evidence indicates that the proximal tubule has a high transepithelial osmotic water permeability in the range of 3500-6000 microns/sec, which is attributable in large part to the high water permeabilities of the cell membranes. Water movement through these membranes may occur through specialized, proteinaceous channels that can be blocked by sulfhydryl reagents. The water channels probably exclude even the smallest solutes and allow only single file movement of the water molecules as do the water channels previously described in the red blood cell and vasopressin-responsive epithelia. If a significant fraction of the water flow also occurs through the junctional complexes, it seems likely that these junctions could be a site for solute solvent coupling which would contribute to solute absorption by solvent drag and which would be responsible for non-unity reflection coefficients for some solutes such as Na+ and Cl-. This possibility is still a matter of vigorous debate. Since the transepithelial water permeability is high, only a very small osmolality difference (1-10 mOsM) is required to drive normally observed rates of volume absorption both in vivo and in vitro. The osmolality difference is produced at least in part by dilution of the luminal fluid and is possibly augmented by the development of interstitial hyperosmolality because of the rapid transport of preferentially absorbed solutes. In the future it is likely that the most important work in this field will relate to the factors that alter transepithelial water permeability and the solute and water permeabilities of the junctional complexes. Investigation in this area is essential in understanding how changes in capillary and interstitial hydrostatic and colloid osmotic pressure may affect volume absorption. PMID:2184773