Integrated Control of Na Transport along the Nephron

PubMed Central

Schnermann, Jürgen

2015-01-01

The kidney filters vast quantities of Na at the glomerulus but excretes a very small fraction of this Na in the final urine. Although almost every nephron segment participates in the reabsorption of Na in the normal kidney, the proximal segments (from the glomerulus to the macula densa) and the distal segments (past the macula densa) play different roles. The proximal tubule and the thick ascending limb of the loop of Henle interact with the filtration apparatus to deliver Na to the distal nephron at a rather constant rate. This involves regulation of both filtration and reabsorption through the processes of glomerulotubular balance and tubuloglomerular feedback. The more distal segments, including the distal convoluted tubule (DCT), connecting tubule, and collecting duct, regulate Na reabsorption to match the excretion with dietary intake. The relative amounts of Na reabsorbed in the DCT, which mainly reabsorbs NaCl, and by more downstream segments that exchange Na for K are variable, allowing the simultaneous regulation of both Na and K excretion. PMID:25098598

Basolateral phosphate transport in renal proximal-tubule-like OK cells.

PubMed

Barac-Nieto, M; Alfred, M; Spitzer, A

2002-09-01

It is generally assumed that phosphate (Pi) effluxes from proximal tubule cells by passive diffusion across the basolateral (BL) membrane. We explored the mechanism of BL Pi efflux in proximal tubule-like OK cells grown on permeable filters and then loaded with 32P. BL efflux of 32P was significantly stimulated (P < 0.05) by exposing the BL side of the monolayer to 12.5 mM Pi, to 10 mM citrate, or by acid-loading the cells, and was inhibited by exposure to 0.05 mM Pi or 25 mM HCO3; by contrast, BL exposure to high (8.4) pH, 40 mM K+, 140 mM Na gluconate (replacing NaCl), 10 mM lactate, 10 mM succinate, or 10 mM glutamate did not affect BL 32P efflux. These data are consistent with BL Pi efflux from proximal tubule-like cells occurring, in part, via an electro-neutral sodium-sensitive anion transporter capable of exchanging two moles of intracellular acidic H2PO4- for each mole of extracellular basic HPO4= or for citrate.

Tight junctions of the proximal tubule and their channel proteins.

PubMed

Fromm, Michael; Piontek, Jörg; Rosenthal, Rita; Günzel, Dorothee; Krug, Susanne M

2017-08-01

The renal proximal tubule achieves the majority of renal water and solute reabsorption with the help of paracellular channels which lead through the tight junction. The proteins forming such channels in the proximal tubule are claudin-2, claudin-10a, and possibly claudin-17. Claudin-2 forms paracellular channels selective for small cations like Na + and K + . Independently of each other, claudin-10a and claudin-17 form anion-selective channels. The claudins form the paracellular "pore pathway" and are integrated, together with purely sealing claudins and other tight junction proteins, in the belt of tight junction strands surrounding the tubular epithelial cells. In most species, the proximal tubular tight junction consists of only 1-2 (pars convoluta) to 3-5 (pars recta) horizontal strands. Even so, they seal the tubule very effectively against leak passage of nutrients and larger molecules. Remarkably, claudin-2 channels are also permeable to water so that 20-25% of proximal water absorption may occur paracellularly. Although the exact structure of the claudin-2 channel is still unknown, it is clear that Na + and water share the same pore. Already solved claudin crystal structures reveal a characteristic β-sheet, comprising β-strands from both extracellular loops, which is anchored to a left-handed four-transmembrane helix bundle. This allowed homology modeling of channel-forming claudins present in the proximal tubule. The surface of cation- and anion-selective claudins differ in electrostatic potentials in the area of the proposed ion channel, resulting in the opposite charge selectivity of these claudins. Presently, while models of the molecular structure of the claudin-based oligomeric channels have been proposed, its full understanding has only started.

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

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

Efficient Proximity Computation Techniques Using ZIP Code Data for Smart Cities †

PubMed Central

Murdani, Muhammad Harist; Hong, Bonghee

2018-01-01

In this paper, we are interested in computing ZIP code proximity from two perspectives, proximity between two ZIP codes (Ad-Hoc) and neighborhood proximity (Top-K). Such a computation can be used for ZIP code-based target marketing as one of the smart city applications. A naïve approach to this computation is the usage of the distance between ZIP codes. We redefine a distance metric combining the centroid distance with the intersecting road network between ZIP codes by using a weighted sum method. Furthermore, we prove that the results of our combined approach conform to the characteristics of distance measurement. We have proposed a general and heuristic approach for computing Ad-Hoc proximity, while for computing Top-K proximity, we have proposed a general approach only. Our experimental results indicate that our approaches are verifiable and effective in reducing the execution time and search space. PMID:29587366

Efficient Proximity Computation Techniques Using ZIP Code Data for Smart Cities †.

PubMed

Murdani, Muhammad Harist; Kwon, Joonho; Choi, Yoon-Ho; Hong, Bonghee

2018-03-24

In this paper, we are interested in computing ZIP code proximity from two perspectives, proximity between two ZIP codes ( Ad-Hoc ) and neighborhood proximity ( Top-K ). Such a computation can be used for ZIP code-based target marketing as one of the smart city applications. A naïve approach to this computation is the usage of the distance between ZIP codes. We redefine a distance metric combining the centroid distance with the intersecting road network between ZIP codes by using a weighted sum method. Furthermore, we prove that the results of our combined approach conform to the characteristics of distance measurement. We have proposed a general and heuristic approach for computing Ad-Hoc proximity, while for computing Top-K proximity, we have proposed a general approach only. Our experimental results indicate that our approaches are verifiable and effective in reducing the execution time and search space.

Functional similarities between pleura and the renal proximal tubule--membrane and cellular considerations.

PubMed

Gourgoulianis, Konstantinos I; Hatzoglou, Chryssi; Molyvdas, Paschalis-Adam

2005-01-01

The small amount of liquid that, under physiological conditions, is presented in the pleural cavity has been the focus of extensive research for more than a century. However, there are still unanswered questions and considerable controversies about the nature of the forces governing its movement into and out of the pleural cavity. Early in the 20th century has been proposed that pleural fluid turnover is simple based on the balance between hydraulic and colloid osmotic pressures existing across the pleural membranes. This original hypothesis has not been validated by data accumulating over the last 20 years. Pleural tissues and renal proximal tubules present high water permeability, small transepithelial electrical resistance (22.02 Omega cm2) and the same cation transportation such as Na+ channels, Na+-K+ ATPase channels, and Na+-H+ exchanger. In contrast to previous conflicting theories concerning pleura fluid movement, the same functional characteristics suggest the hypothesis that physiology of pleura is similar to proximal tubules.

Localization of the Calcium Regulated Citrate Transport Process in Proximal Tubule Cells

PubMed Central

Hering-Smith, Kathleen S.; Mao, Weibo; Schiro, Faith R.; Coleman-Barnett, Joycelynn; Pajor, Ana M.; Hamm, L. Lee

2014-01-01

Urinary citrate is an important inhibitor of calcium stone formation. Most of citrate reabsorption in the proximal tubule is thought to occur via a dicarboxylate transporter NaDC1 located in the apical membrane. OK cells, an established opossum kidney proximal tubule cell line, transport citrate but the characteristics change with extracellular calcium such that low calcium solutions stimulate total citrate transport as well as increase the apparent affinity for transport. The present studies address several fundamental properties of this novel process: the polarity of the transport process, the location of the calcium-sensitivity and whether NaDC1 is present in OK cells. OK cells grown on permeable supports exhibited apical > basolateral citrate transport. Apical transport of both citrate and succinate was sensitive to extracellular calcium whereas basolateral transport was not. Apical calcium, rather than basolateral, was the predominant determinant of changes in transport. Also 2,3-dimethylsuccinate, previously identified as an inhibitor of basolateral dicarboxylate transport, inhibited apical citrate uptake. Although the calcium-sensitive transport process in OK cells is functionally not typical NaDC1, NaDC1 is present in OK cells by Western blot and PCR. By immunolocalization studies, NaDC1 was predominantly located in discrete apical membrane or subapical areas. However by biotinylation, apical NaDC1 decreases in the apical membrane with lowering calcium. In sum, OK cells express a calcium-sensitive/regulated dicarboxylate process at the apical membrane which responds to variations in apical calcium. Despite the functional differences of this process compared to NaDC1, NaDC1 is present in these cells, but predominantly in subapical vesicles. PMID:24652587

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

Biomechanical risk factors for proximal junctional kyphosis: a detailed numerical analysis of surgical instrumentation variables.

PubMed

Cammarata, Marco; Aubin, Carl-Éric; Wang, Xiaoyu; Mac-Thiong, Jean-Marc

2014-04-15

Biomechanical analysis of proximal junctional kyphosis (PJK) through computer simulations and sensitivity analysis. To gain biomechanical knowledge on the risk of PJK and find surgical solutions to reduce the risks. PJK is a pathological kyphotic deformity adjacent to the instrumentation. Clinical studies have documented its risk factors, but still little is known on how it is correlated with various individual instrumentation variables. Biomechanical spine models of 6 patients with adult scoliosis were developed, validated, and then used to perform 576 simulations, varying the proximal dissection procedure, the implant type at the upper instrumented vertebra, the sagittal rod curvature, and the proximal diameter of the proximal transition rods. Four biomechanical indices--the proximal junctional kyphotic angle, thoracic kyphosis, proximal flexion force, and proximal flexion moment--were assessed. The bilateral complete facetectomy, the posterior ligaments resection, and the combination of both increased the proximal junctional kyphotic angle (respectively, by 10%, 28% and 53%) and the proximal flexion force (4%, 12%, and 22%) and moment (16%, 44%, and 83%). Compared with pedicle screws at upper instrumented vertebra, proximal transverse process hooks reduced the 3 biomechanical indices by approximately 26%. The use of proximal transition rods with reduced proximal diameter from 5.5 mm to 4 mm decreased the proximal junctional kyphotic angle (by 6%) and the proximal flexion force (4%) and moment (8%). The increase of the sagittal rod curvature from 10° to 20°, 30°, and 40° increased the proximal junctional kyphotic angle (by 6%, 13%, and 19%) and the proximal flexion force (3%, 7%, and 10%) and moment (9%, 18%, and 27%). Preserving more posterior proximal intervertebral elements, the use of transition rods and transverse process hooks at upper instrumented vertebra, and reducing the global sagittal rod curvature each decreased the 4 biomechanical indices that

Proximity matching for ArF and KrF scanners

NASA Astrophysics Data System (ADS)

Kim, Young Ki; Pohling, Lua; Hwee, Ng Teng; Kim, Jeong Soo; Benyon, Peter; Depre, Jerome; Hong, Jongkyun; Serebriakov, Alexander

2009-03-01

There are many IC-manufacturers over the world that use various exposure systems and work with very high requirements in order to establish and maintain stable lithographic processes of 65 nm, 45 nm and below. Once the process is established, manufacturer desires to be able to run it on different tools that are available. This is why the proximity matching plays a key role to maximize tools utilization in terms of productivity for different types of exposure tools. In this paper, we investigate the source of errors that cause optical proximity mismatch and evaluate several approaches for proximity matching of different types of 193 nm and 248 nm scanner systems such as set-get sigma calibration, contrast adjustment, and, finally, tuning imaging parameters by optimization with Manual Scanner Matcher. First, to monitor the proximity mismatch, we collect CD measurement data for the reference tool and for the tool-to-be-matched. Normally, the measurement is performed for a set of line or space through pitch structures. Secondly, by simulation or experiment, we determine the sensitivity of the critical structures with respect to small adjustment of exposure settings such as NA, sigma inner, sigma outer, dose, focus scan range etc. that are called 'proximity tuning knobs'. Then, with the help of special optimization software, we compute the proximity knob adjustment that has to be applied to the tool-to-be-matched to match the reference tool. Finally, we verify successful matching by exposing on the tool-to-be-matched with tuned exposure settings. This procedure is applicable for inter- and intra scanner type matching, but possibly also for process transfers to the design targets. In order to illustrate the approach we show experimental data as well as results of imaging simulations. The set demonstrate successful matching of critical structures for ArF scanners of different tool generations.

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

Far infrared radiation promotes rabbit renal proximal tubule cell proliferation and functional characteristics, and protects against cisplatin-induced nephrotoxicity.

PubMed

Chiang, I-Ni; Pu, Yeong-Shiau; Huang, Chao-Yuan; Young, Tai-Horng

2017-01-01

Far infrared radiation, a subdivision of the electromagnetic spectrum, is beneficial for long-term tissue healing, anti-inflammatory effects, growth promotion, sleep modulation, acceleration of microcirculation, and pain relief. We investigated if far infrared radiation is beneficial for renal proximal tubule cell cultivation and renal tissue engineering. We observed the effects of far infrared radiation on renal proximal tubules cells, including its effects on cell proliferation, gene and protein expression, and viability. We also examined the protective effects of far infrared radiation against cisplatin, a nephrotoxic agent, using the human proximal tubule cell line HK-2. We found that daily exposure to far infrared radiation for 30 min significantly increased rabbit renal proximal tubule cell proliferation in vitro, as assessed by MTT assay. Far infrared radiation was not only beneficial to renal proximal tubule cell proliferation, it also increased the expression of ATPase Na+/K+ subunit alpha 1 and glucose transporter 1, as determined by western blotting. Using quantitative polymerase chain reaction, we found that far infrared radiation enhanced CDK5R1, GNAS, NPPB, and TEK expression. In the proximal tubule cell line HK-2, far infrared radiation protected against cisplatin-mediated nephrotoxicity by reducing apoptosis. Renal proximal tubule cell cultivation with far infrared radiation exposure resulted in better cell proliferation, significantly higher ATPase Na+/K+ subunit alpha 1 and glucose transporter 1 expression, and significantly enhanced expression of CDK5R1, GNAS, NPPB, and TEK. These results suggest that far infrared radiation improves cell proliferation and differentiation. In HK-2 cells, far infrared radiation mediated protective effects against cisplatin-induced nephrotoxicity by reducing apoptosis, as indicated by flow cytometry and caspase-3 assay.

Distinct mechanisms underlie adaptation of proximal tubule Na+/H+ exchanger isoform 3 in response to chronic metabolic and respiratory acidosis.

PubMed

Silva, Pedro Henrique Imenez; Girardi, Adriana Castello Costa; Neri, Elida Adalgisa; Rebouças, Nancy Amaral

2012-04-01

The Na(+/)H(+) exchanger isoform 3 (NHE3) is essential for HCO(3)(-) reabsorption in renal proximal tubules. The expression and function of NHE3 must adapt to acid-base conditions. The goal of this study was to elucidate the mechanisms responsible for higher proton secretion in proximal tubules during acidosis and to evaluate whether there are differences between metabolic and respiratory acidosis with regard to NHE3 modulation and, if so, to identify the relevant parameters that may trigger these distinct adaptive responses. We achieved metabolic acidosis by lowering HCO(3)(-) concentration in the cell culture medium and respiratory acidosis by increasing CO(2) tension in the incubator chamber. We found that cell-surface NHE3 expression was increased in response to both forms of acidosis. Mild (pH 7.21 ± 0.02) and severe (6.95 ± 0.07) metabolic acidosis increased mRNA levels, at least in part due to up-regulation of transcription, whilst mild (7.11 ± 0.03) and severe (6.86 ± 0.01) respiratory acidosis did not up-regulate NHE3 expression. Analyses of the Nhe3 promoter region suggested that the regulatory elements sensitive to metabolic acidosis are located between -466 and -153 bp, where two consensus binding sites for SP1, a transcription factor up-regulated in metabolic acidosis, were localised. We conclude that metabolic acidosis induces Nhe3 promoter activation, which results in higher mRNA and total protein level. At the plasma membrane surface, NHE3 expression was increased in metabolic and respiratory acidosis alike, suggesting that low pH is responsible for NHE3 displacement to the cell surface.

Proximal Tibial Bone Graft

MedlinePlus

... All Site Content AOFAS / FootCareMD / Treatments Proximal Tibial Bone Graft Page Content What is a bone graft? Bone grafts may be needed for various ... the proximal tibia. What is a proximal tibial bone graft? Proximal tibial bone graft (PTBG) is a ...

Visualization of Calcium Dynamics in Kidney Proximal Tubules

PubMed Central

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.

2015-01-01

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. PMID:25788535

SGLT2 mediates glucose reabsorption in the early proximal tubule.

PubMed

Vallon, Volker; Platt, Kenneth A; Cunard, Robyn; Schroth, Jana; Whaley, Jean; Thomson, Scott C; Koepsell, Hermann; Rieg, Timo

2011-01-01

Mutations in the gene encoding for the Na(+)-glucose co-transporter SGLT2 (SLC5A2) associate with familial renal glucosuria, but the role of SGLT2 in the kidney is incompletely understood. Here, we determined the localization of SGLT2 in the mouse kidney and generated and characterized SGLT2-deficient mice. In wild-type (WT) mice, immunohistochemistry localized SGLT2 to the brush border membrane of the early proximal tubule. Sglt2(-/-) mice had glucosuria, polyuria, and increased food and fluid intake without differences in plasma glucose concentrations, GFR, or urinary excretion of other proximal tubular substrates (including amino acids) compared with WT mice. SGLT2 deficiency did not associate with volume depletion, suggested by similar body weight, BP, and hematocrit; however, plasma renin concentrations were modestly higher and plasma aldosterone levels were lower in Sglt2(-/-) mice. Whole-kidney clearance studies showed that fractional glucose reabsorption was significantly lower in Sglt2(-/-) mice compared with WT mice and varied in Sglt2(-/-) mice between 10 and 60%, inversely with the amount of filtered glucose. Free-flow micropuncture revealed that for early proximal collections, 78 ± 6% of the filtered glucose was reabsorbed in WT mice compared with no reabsorption in Sglt2(-/-) mice. For late proximal collections, fractional glucose reabsorption was 93 ± 1% in WT and 21 ± 6% in Sglt2(-/-) mice, respectively. These results demonstrate that SGLT2 mediates glucose reabsorption in the early proximal tubule and most of the glucose reabsorption by the kidney, overall. This mouse model mimics and explains the glucosuric phenotype of individuals carrying SLC5A2 mutations.

Ischemia/Reperfusion Model Impairs Endocannabinoid Signaling and Na+/K+ ATPase Expression and Activity in Kidney Proximal Tubule Cells.

PubMed

Sampaio, Luzia S; Iannotti, Fabio A; Veneziani, Luciana; Borelli-Tôrres, Rosa T; De Maio, Fabrizia; Piscitelli, Fabiana; Reis, Ricardo A M; Di Marzo, Vincenzo; Einicker-Lamas, Marcelo

2018-06-08

LLC-PK1 cells, an immortalized epithelial cell line derived from pig renal proximal tubules, express all the major players of the endocannabinoid system (ECS) such as CB1, CB2 and TRPV1 receptor, as well as the main enzymes involved in the biosynthesis and degradation of the major endocannabinoids named 2-arachidonoylglycerol, 2-AG and anandamide, AEA. Here we investigated whether the damages caused by ischemic insult either in vitro using LLC-PK1 cells exposed to antimycin A (an inductor of ATP-depletion) or in vivo using Wistar rats in a classic renal ischemia and reperfusion (IR) protocol, lead to changes in AEA and 2-AG levels, as well as altered expression of genes from the main enzymes involved in the regulation of the ECS. Our data show that the mRNA levels of CB1 receptor gene were downregulated, while the transcript levels of monoacylglycerol lipase (MAGL), the main 2-AG degradative enzyme, are upregulated in LLC-PK1 cells after IR model. Accordingly, IR was accompanied by a significant reduction in the levels of 2-AG and AEA, as well as of the two endocannabinoid related molecules, oleoylethanolamide (OEA) and palmitoylethanolamide (PEA) in LLC-PK1 cells. In kidney cortex homogenates, the AEA levels were selectively significantly decreased. In addition, we found that both the in vitro and in vivo model of IR caused a reduction in the expression and activity of the Na + /K + ATPase. These changes were reversed by the CB1/CB2 agonist WIN55,212, in a CB1-receptor dependent manner on LLC-PK1 IR model. In conclusion, the ECS and Na + /K + ATPase are down-regulated following IR model in LLC-PK1 cells and rat kidney. We suggest that CB1 agonists might represent a potential strategy to reverse the consequences of IR injury in kidney tissues. Copyright © 2018 Elsevier Inc. All rights reserved.

Proximal Hypospadias

PubMed Central

Kraft, Kate H.; Shukla, Aseem R.; Canning, Douglas A.

2011-01-01

Hypospadias results from abnormal development of the penis that leaves the urethral meatus proximal to its normal glanular position. Meatal position may be located anywhere along the penile shaft, but more severe forms of hypospadias may have a urethral meatus located at the scrotum or perineum. The spectrum of abnormalities may also include ventral curvature of the penis, a dorsally redundant prepuce, and atrophic corpus spongiosum. Due to the severity of these abnormalities, proximal hypospadias often requires more extensive reconstruction in order to achieve an anatomically and functionally successful result. We review the spectrum of proximal hypospadias etiology, presentation, correction, and possible associated complications. PMID:21516286

Proximal tubule hydrogen ion transport processes in diuretic-induced metabolic alkalosis.

PubMed

Blumenthal, S S; Ware, R A; Kleinman, J G

1985-07-01

Transport systems involved in proximal tubule HCO-3 reabsorption were examined in disaggregated renal cortical tubules from rabbits with metabolic alkalosis. The acid-base disorder was induced by first treating the animals with furosemide, and then maintaining them on low Cl--high HCO-3 diets. On this regimen, the rabbits had increases in blood pH and total CO2 values and decreases in serum K+ concentrations. Urine Cl- concentrations were less than 15 mEq/L in all cases. Na+-H+ exchange was evaluated by incubating tubules in rotenone in an Na+-free medium to deplete them of Na+ and adenosine triphosphate. Then the tubules were resuspended in media containing 65 or 12.5 mEq/L Na+ at either pH 7.1 or pH 7.6. The rise in cell pH estimated by dimethadione distribution was taken as a measure of Na+-H+ exchanger activity. At the high incubation pH, Na+-H+ exchanger activity appeared to be the same in tubules taken from alkalotic rabbits compared with those prepared from normal rabbits. At the low incubation pH, the activity of this transport system appeared to be depressed by 40% to 50% in alkalosis, with kinetics that suggested a decreased Vmax for the exchanger. Na+-independent H+ transport, presumably reflecting activity of an H+-adenosine triphosphatase, was evaluated by preincubating tubules in a Na+-free medium in the presence of ouabain, and then sequentially exposing them to and removing them from a solution containing 20 mmol/L NH4Cl.(ABSTRACT TRUNCATED AT 250 WORDS)

Fluorine-18 NaF PET imaging of child abuse.

PubMed

Drubach, Laura A; Sapp, Mark V; Laffin, Stephen; Kleinman, Paul K

2008-07-01

We describe the use of 18F-NaF positron emission tomography (PET) whole-body imaging for the evaluation of skeletal trauma in a case of suspected child abuse. To our knowledge, 18F NaF PET has not been used in the past for the evaluation of child abuse. In our patient, this technique detected all sites of trauma shown by initial and follow-up skeletal surveys, including bilateral metaphyseal fractures of the proximal humeri. Fluorine-18 NaF PET has potential advantage over Tc-99m-labeled methylene diphosphonate (MDP) based upon superior image contrast and spatial resolution.

Transport characteristics of L-citrulline in renal apical membrane of proximal tubular cells.

PubMed

Mitsuoka, Keisuke; Shirasaka, Yoshiyuki; Fukushi, Akimasa; Sato, Masanobu; Nakamura, Toshimichi; Nakanishi, Takeo; Tamai, Ikumi

2009-04-01

L-Citrulline has diagnostic potential for renal function, because its plasma concentration increases with the progression of renal failure. Although L-citrulline extracted by glomerular filtration in kidney is mostly reabsorbed, the mechanism involved is not clearly understood. The present study was designed to characterize L-citrulline transport across the apical membranes of renal epithelial tubular cells, using primary-cultured rat renal proximal tubular cells, as well as the human kidney proximal tubular cell line HK-2. L-Citrulline was transported in a Na(+)-dependent manner from the apical side of both cell types cultured on permeable supports with a microporous membrane. Kinetic analysis indicated that the transport involves two distinct Na(+)-dependent saturable systems and one Na(+)-independent saturable system in HK-2 cells. The uptake was competitively inhibited by neutral and cationic, but not anionic amino acids. Relatively large cationic and anionic compounds inhibited the uptake, but smaller ones did not. In HK-2 cells, mRNA expression of SLC6A19 and SLC7A9, which encode B(0)AT1 and b(0,+)AT, respectively, was detected by RT-PCR. In addition, L-citrulline transport was significantly decreased in HK-2 cells in which either SLC6A19 or SLC7A9 was silenced. Hence, these results suggest that amino acid transporters B(0)AT1 and b(0,+)AT are involved in the reabsorption of L-citrulline in the kidney, at least in part, by mediating the apical membrane transport of L-citrulline in renal tubule cells.

Proximal Junctional Kyphosis.

PubMed

Kim, Han Jo; Iyer, Sravisht

2016-05-01

Proximal junctional kyphosis (PJK) is a common complication following adult spinal deformity surgery. It is defined by two criteria: a proximal junctional sagittal Cobb angle (1) ≥ 10° and (2) at least 10° greater than the preoperative measurement. PJK is multifactorial in origin and likely stems from surgical, radiographic, and patient-related risk factors. The diagnosis of PJK represents a broad spectrum of disease ranging from asymptomatic patients with recurrence of deformity to those presenting with increased pain, functional deficit, and, in the most severe cases, neurologic deficits. Recent studies have demonstrated increased pain levels in select patients with PJK. In keeping with the broad spectrum of the disease, classification schemes are needed to better describe and stratify the severity of PJK. The most severe form is proximal junctional failure. A consensus on a uniform definition of proximal junctional failure is needed to allow for more systematic study of this phenomenon.

Mechanism of bicarbonate exit across basolateral membrane of rabbit proximal straight tubule.

PubMed

Sasaki, S; Shiigai, T; Yoshiyama, N; Takeuchi, J

1987-01-01

To clarify the mechanism(s) of HCO3- (or related base) transport across the basolateral membrane, rabbit proximal straight tubules were perfused in vitro, and intracellular pH (pHi) and Na+ activity (aiNa) were measured by double-barreled ion-selective microelectrodes. Lowering bath HCO3- from 25 to 5 mM at constant PCO2 depolarized basolateral membrane potential (Vbl), and reduced pHi. Most of these changes were inhibited by adding 1 mM 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS) to the bath. Total replacement of bath Na+ with choline also depolarized Vbl and reduced pHi, and these changes were also inhibited by SITS. Reduction in aiNa was observed when bath HCO3- was lowered. Taken together, these findings suggest that HCO3- exists the basolateral membrane with Na+ and negative charge. Calculation of the electrochemical driving forces suggests that the stoichiometry of HCO3-/Na+ must be larger than two for maintaining HCO3- efflux. Total replacement of bath Cl- with isethionate depolarized Vbl gradually and increased pHi slightly, implying the existence of a Cl(-)-related HCO3- exit mechanism. The rate of decrease in pHi induced by lowering bath HCO3- was slightly reduced (20%) by the absence of bath Cl-. Therefore, the importance of Cl(-)-related HCO3- transport is small relative to total basolateral HCO3- exit. Accordingly, these data suggest that most of HCO3- exits the basolateral membrane through the rheogenic Na+/HCO3- cotransport mechanism with a stoichiometry of HCO3-/Na+ of more than two.

BSC-1 growth inhibitor transforms a mitogenic stimulus into a hypertrophic stimulus for renal proximal tubular cells: relationship to Na/sup +//H/sup +/ antiport activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fine, L.G.; Holley, R.W.; Nasri, H.

Renal hypertrophy is characterized by an increase in cell size and protein content with minimal hyperplasia. The mechanisms of control of this pattern of cell growth have not been determined. The present studies examined whether the growth inhibitor elaborated by BSC-1 kidney epilethal cells (GI), which has nearly identical biological properties to transforming growth factor ..beta.. (TGF-..beta..), could transform a mitogenic stimulus into a hypertrophic stimulus for rabbit renal proximal tubular cells in primary culture. Insulin plus hydrocortisone increased the amount of protein per cell, cell volume, and (/sup 3/H)thymidine incorporation at 24 and 48 hr in these cells. Whenmore » added together with insulin plus hydrocortisone, GI/TGF-..beta.. inhibited the stimulatory effect of these mitogens on (/sup 3/H)thymidine incorporation but did not block the increase in protein per cell and cell volume - i.e., the cells underwent hypertrophy. The fact that this pattern persisted for 48 hr indicated that GI/TGF-..beta.. exerted a prolonged inhibitory effect on mitogenic-stimulated DNA synthesis rather than delaying its onset. Amiloride-sensitive Na/sup +/ uptake using /sup 22/Na/sup +/ as a tracer, correlated with protein per cell and cell volume rather than with DNA synthesis. These studies indicate that the control of cell size may be regulated by autocrine mechanisms mediated by the elaboration of growth inhibitory factors that alter the pattern of the growth response to mitogens.« less

Na+-independent D-glucose transport in rabbit renal basolateral membranes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheung, P.T.; Hammerman, M.R.

1988-05-01

To define the mechanism by which glucose is transported across the basolateral membrane of the renal proximal tubular cell, we measured D-(14C)glucose uptake in basolateral membrane vesicles from rabbit kidney. Na+-dependent D-glucose transport, demonstrable in brush-border vesicles, could not be demonstrated in basolateral membrane vesicles. In the absence of Na+, the uptake of D-(14C)glucose in basolateral vesicles was more rapid than that of L-(3H)glucose over a concentration range of 1-50 mM. Subtraction of the latter from the former uptakes revealed a saturable process with apparent Km of 9.9 mM and Vmax of 0.80 nmol.mg protein-1.s-1. To characterize the transport componentmore » of D-glucose uptake in basolateral vesicles, we measured trans stimulation of 2 mM D-(14C)glucose entry in the absence of Na+. Trans stimulation could be effected by preloading basolateral vesicles with D-glucose, 2-deoxy-D-glucose, or 3-O-methyl-D-glucose, but not with L-glucose or alpha-methyl-D-glucoside. Trans-stimulated D-(14C)glucose uptake was inhibited by 0.1 mM phloretin or cytochalasin B but not phlorizin. In contrast, Na+-dependent D-(14C)glucose transport in brush-border vesicles was inhibited by phlorizin but not phloretin or cytochalasin B. Our findings are consistent with the presence of a Na+-independent D-glucose transporter in the proximal tubular basolateral membrane with characteristics similar to those of transporters present in nonepithelial cells.« less

Missense mutation T485S alters NBCe1-A electrogenicity causing proximal renal tubular acidosis

PubMed Central

Shao, Xuesi M.; Kao, Liyo; Azimov, Rustam; Weinstein, Alan M.; Newman, Debra; Liu, Weixin; Kurtz, Ira

2013-01-01

Mutations in SLC4A4, the gene encoding the electrogenic Na+-HCO3− cotransporter NBCe1, cause severe proximal renal tubular acidosis (pRTA), growth retardation, decreased IQ, and eye and teeth abnormalities. Among the known NBCe1 mutations, the disease-causing mechanism of the T485S (NBCe1-A numbering) mutation is intriguing because the substituted amino acid, serine, is structurally and chemically similar to threonine. In this study, we performed intracellular pH and whole cell patch-clamp measurements to investigate the base transport and electrogenic properties of NBCe1-A-T485S in mammalian HEK 293 cells. Our results demonstrated that Ser substitution of Thr485 decreased base transport by ∼50%, and importantly, converted NBCe1-A from an electrogenic to an electroneutral transporter. Aqueous accessibility analysis using sulfhydryl reactive reagents indicated that Thr485 likely resides in an NBCe1-A ion interaction site. This critical location is also supported by the finding that G486R (a pRTA causing mutation) alters the position of Thr485 in NBCe1-A thereby impairing its transport function. By using NO3− as a surrogate ion for CO32−, our result indicated that NBCe1-A mediates electrogenic Na+-CO32− cotransport when functioning with a 1:2 charge transport stoichiometry. In contrast, electroneutral NBCe1-T485S is unable to transport NO3−, compatible with the hypothesis that it mediates Na+-HCO3− cotransport. In patients, NBCe1-A-T485S is predicted to transport Na+-HCO3− in the reverse direction from blood into proximal tubule cells thereby impairing transepithelial HCO3− absorption, possibly representing a new pathogenic mechanism for generating human pRTA. PMID:23636456

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.

Characterisation of human tubular cell monolayers as a model of proximal tubular xenobiotic handling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Colin D.A.; Sayer, Rachel; Windass, Amy S.

2008-12-15

The aim of this study was to determine whether primary human tubular cell monolayers could provide a powerful tool with which to investigate the renal proximal tubular handling of xenobiotics. Human proximal and distal tubule/collecting duct cells were grown as monolayers on permeable filter supports. After 10 days in culture, proximal tubule cells remained differentiated and expressed a wide palette of transporters at the mRNA level including NaPi-IIa, SGLT1, SGLT2, OCT2, OCTN2, OAT1, OAT3, OAT4, MDR1, MRP2 and BCRP. At the protein level, the expression of a subset of transporters including NaPi-IIa, OAT1 and OAT3 was demonstrated using immunohistochemistry. Analysismore » of the expression of the ATP binding cassette efflux pumps MDR1, MRP2 and BCRP confirmed their apical membrane localisation. At the functional level, tubule cell monolayers retain the necessary machinery to mediate the net secretion of the prototypic substrates; PAH and creatinine. PAH secretion across the monolayer consisted of the uptake of PAH across the basolateral membrane by OAT1 and OAT3 and the apical exit of PAH by a probenecid and MK571-sensitive route consistent with actions of MRP2 or MRP4. Creatinine secretion was by OCT2-mediated uptake at the basolateral membrane and via MDR1 at the apical membrane. Functional expression of MDR1 and BCRP at the apical membrane was also demonstrated using a Hoechst 33342 dye. Similarly, measurement of calcein efflux demonstrated the functional expression of MRP2 at the apical membrane of cell monolayers. In conclusion, human tubular cell monolayers provide a powerful tool to investigate renal xenobiotic handling.« less

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.

Role of NF-κB in oxidative stress-induced defective dopamine D1 receptor signaling in the renal proximal tubules of Sprague Dawley rats

PubMed Central

Fardoun, Riham Zein; Asghar, Mohammad; Lokhandwala, Mustafa

2009-01-01

Dopamine promotes sodium excretion, in part, via activation of D1 receptors in renal proximal tubules (PT) and subsequent inhibition of Na, K-ATPase. Recently, we have reported that oxidative stress causes D1 receptors-G-protein uncoupling via mechanisms involving Protein Kinase C (PKC) and G-protein Coupled Receptor Kinase 2 (GRK2) in the primary culture of renal PT of Sprague Dawley (SD) rats. There are reports suggesting that redox-sensitive nuclear transcription factor, NF-κB, is activated in conditions associated with oxidative stress. This study was designed to identify the role of NF-κB in oxidative stress–induced defective renal D1 receptor –G-protein coupling and function. Treatment of the PT with hydrogen peroxide (H2O2, 50 μM/20 min) induced the nuclear translocation of NF-κB, increased PKC activity, and triggered the translocation of GRK2 to the proximal tubular membranes. This was accompanied by hyperphosphorylation of D1 receptors and defective D1 receptor-G-protein coupling. The functional consequence of these changes was decreased D1 receptor activation-mediated inhibition of Na, K-ATPase activity. Interestingly, pre-treatment with pyrrolidine dithiocarbamate (PDTC, 25 μM/10min), an NF-κB inhibitor, blocked the H2O2-induced nuclear translocation of NF-κB, increase in PKC activity, as well as GRK2 translocation and hyperphosphorylation of D1 receptors in the proximal tubular membranes. Furthermore, PDTC restored D1 receptor G-protein coupling and D1 receptor agonist-mediated inhibition of the Na, KATPase activity. Therefore, we suggest that oxidative stress causes nuclear translocation of NF-κB in the renal proximal tubules, which contributes to defective D1-receptor-G-protein coupling and function via mechanism involving PKC, membranous translocation of GRK 2, and subsequent phosphorylation of dopamine D1 receptors. PMID:17320758

Glucagon-like peptide 1 receptor expression in primary porcine proximal tubular cells.

PubMed

Schlatter, P; Beglinger, C; Drewe, J; Gutmann, H

2007-06-07

GLP-1 is secreted into the circulation after food intake. The main biological effects of GLP-1 include stimulation of glucose dependent insulin secretion and induction of satiety feelings. Recently, it was demonstrated in rats and humans that GLP-1 can stimulate renal excretion of sodium. Based on these data, the existence of a renal GLP-1 receptor (GLP-1R) was postulated. However, the exact localization of the GLP-1R and the mechanism of this GLP-1 action have not yet been investigated. Primary porcine proximal tubular cells were isolated from porcine kidneys. Expression of GLP-1R was measured at the mRNA level by quantitative RT-PCR. Protein expression of GLP-1R was verified with immunocytochemistry, immunohistochemistry and Western blot analysis. Functional studies included transport assessments of sodium and glucose using three different GLP-1 concentrations (200 pM, 2 nM and 20 nM), 200 pM exendin-4 (GLP-1 analogue) and an inhibitor of the dipeptidylpeptidase IV (DPPIV) enzyme (P32/98 at 10 microM). Finally, the expression of NHE3, the predominant Na(+)/H(+) exchanger in proximal tubular cells, was also investigated. GLP-1R, NHE3 and DPPIV were expressed at the mRNA level in porcine proximal tubular kidney cells. GLP-1R expression was confirmed at the protein level. Staining of human and pig kidney cortex revealed that GLP-1R was predominantly expressed in proximal tubular cells. Functional assays demonstrated an inhibition of sodium re-absorption with GLP-1 after 3 h of incubation. Exendin-4 and GLP-1 in combination with P32/98 co-administration had no clear influence on glucose and sodium uptake and transport. GLP-1R is functionally expressed in porcine proximal tubular kidney cells. Addition of GLP-1 to these cells resulted in a reduced sodium re-absorption. GLP-1 had no effect on glucose re-absorption. We conclude that GLP-1 modulates sodium homeostasis in the kidney most likely through a direct action via its GLP-1R in proximal tubular cells.

The mechanisms of brush border Na+/H+ exchanger activation by corticosteroids.

PubMed

Zallocchi, Marisa; Igarreta, Pilar; Calvo, Juan Carlos; Reboucas, Nancy Amaral; Damasco, María Christina

2003-02-01

Previously we showed that corticosterone and aldosterone increased proton fluxes in proximal tubule, by micropuncture and stationary microperfusion. Since the Na+/H+ exchanger is responsible for the main proximal proton secretion, we have now evaluated the effects aldosterone on Na+/H+ exchange activity in brush border vesicles. In order to evaluate the mechanism of action of glucocorticoids and mineralocorticoids, we studied the comparative effects of corticosterone and aldosterone on the abundance of NHE3 and NHE2 isoforms. We isolated renal brush border vesicles from rats by differential centrifugation in sham-operated, adrenalectomized, and adrenalectomized-aldosterone treated (ADX + aldosterone) animals. We measured the kinetics of H+ transport in response to increasing concentrations of Sodium Gluconate by fluorimetry using acridine orange. For Na+/H+ exchanger abundance we used Western blot analysis of brush border proteins in the above groups and in adrenalectomized-corticosterone treated rats. The Vmax in adrenalectomized animals was 22,162+/-1828 fluorescence units/min; in sham animals, 37,020+/-2722; and in ADX + aldosterone, 42,344+/-3044 (p<0.01 adrenalectomized vs others). No differences in Km were observed. Adrenalectomy decreased NHE3 abundance over Sham by 32% without modifying NHE2. Corticosterone-replacement enhanced NHE3 abundance by 76% and failed to increase NHE2. Aldosterone enhanced NHE2 abundance by 75% and did not increase NHE3. Mineralocorticoids enhance Na+/H+ exchange activity by increasing NHE2 abundance; glucocorticoids, by increasing NHE3 abundance.

Active Targets For Capacitive Proximity Sensors

NASA Technical Reports Server (NTRS)

Jenstrom, Del T.; Mcconnell, Robert L.

1994-01-01

Lightweight, low-power active targets devised for use with improved capacitive proximity sensors described in "Capacitive Proximity Sensor Has Longer Range" (GSC-13377), and "Capacitive Proximity Sensors With Additional Driven Shields" (GSC-13475). Active targets are short-distance electrostatic beacons; they generate known alternating electro-static fields used for alignment and/or to measure distances.

Properties of acetylcholine-induced relaxation of smooth muscle isolated from the proximal colon of the guinea-pig.

PubMed

Kodama, Youhei; Iino, Satoshi; Shigemasa, Yuhsuke; Suzuki, Hikaru

2010-01-01

The properties of mechanical responses elicited by stimulation with acetylcholine (ACh) were investigated in circular smooth muscle preparations isolated from the proximal colon of guinea-pig. Application of ACh (10(-8)-10(-6) M) for 3-5 min produced a biphasic response, with an initial contraction followed by a relaxation. Atropine inhibited the initial contraction, while N(ω)-nitro-L-arginine (L-NA) inhibited the relaxation, suggesting that the former was produced by activation of muscarinic receptors while the latter was produced by an elevated production of nitric oxide (NO). In the presence of atropine, the ACh-relaxation was attenuated by removal of the mucosa and abolished by removal of both submucosal and mucosal layers. The ACh-induced relaxation was also attenuated by either tetrodotoxin (TTX, 3 × 10(-7) M) or hexamethonium (10(-6) M). In the presence of atropine, transmural nerve stimulation (TNS) elicited a biphasic response, with an initial phasic contraction followed by a relaxation. The amplitude of TNS-induced relaxation was significantly reduced by hexamethonium or L-NA and was abolished by TTX. Both ACh and TNS produced relaxation in preparations isolated from the proximal colon, but not in those from the middle part of colon. Immunohistochemistry for neuronal nitric oxide synthase revealed no difference in the distribution of nitrergic nerves between the proximal and middle part of the colon, with nitrergic nerves in both the mucosal and submucosal layers as well as in the smooth muscle and myenteric layers. These results suggest that ACh induces NO production by excitation of postganglionic nerves distributed mainly in the mucosal and submucosal layers. In circular smooth muscle preparations isolated from the middle part of colon, ACh or TNS produced contractile responses alone, with no associated relaxation, suggesting that the ACh-activated postganglionic nitrergic nerves are distributed in the mucosal and submucosal layers of the proximal

A supercritical density of fast Na+ channels ensures rapid propagation of action potentials in GABAergic interneuron axons

PubMed Central

Hu, Hua; Jonas, Peter

2014-01-01

Fast-spiking, parvalbumin-expressing GABAergic interneurons/basket cells (BCs) play a key role in feedforward and feedback inhibition, gamma oscillations, and complex information processing. For these functions, fast propagation of action potentials (APs) from the soma to the presynaptic terminals is important. However, the functional properties of interneuron axons remain elusive. Here, we examined interneuron axons by confocally targeted subcellular patch-clamp recording in rat hippocampal slices. APs were initiated in the proximal axon ~20 μm from the soma, and propagated to the distal axon with high reliability and speed. Subcellular mapping revealed a stepwise increase of Na+ conductance density from the soma to the proximal axon, followed by a further gradual increase in the distal axon. Active cable modeling and experiments with partial channel block indicated that low axonal Na+ conductance density was sufficient for reliability, but high Na+ density was necessary for both speed of propagation and fast-spiking AP phenotype. Our results suggest that a supercritical density of Na+ channels compensates for the morphological properties of interneuron axons (small segmental diameter, extensive branching, and high bouton density), ensuring fast AP propagation and high-frequency repetitive firing. PMID:24657965

Proximity operations considerations affecting spacecraft design

NASA Technical Reports Server (NTRS)

Staas, Steven K.

1991-01-01

Experience from several recent spacecraft development programs, such as Space Station Freedom (SSF) and the Orbital Maneuvering Vehicle (OMV) has shown the need for factoring proximity operations considerations into the vehicle design process. Proximity operations, those orbital maneuvers and procedures which involve operation of two or more spacecraft at ranges of less than one nautical mile, are essential to the construction, servicing, and operation of complex spacecraft. Typical proximity operations considerations which drive spacecraft design may be broken into two broad categories; flight profile characteristics and concerns, and use of various spacecraft systems during proximity operations. Proximity operations flight profile concerns include the following: (1) relative approach/separation line; (2) relative orientation of the vehicles; (3) relative translational and rotational rates; (4) vehicle interaction, in the form of thruster plume impingement, mating or demating operations, or uncontrolled contact/collision; and (5) active vehicle piloting. Spacecraft systems used during proximity operations include the following: (1) sensors, such as radar, laser ranging devices, or optical ranging systems; (2) effector hardware, such as thrusters; (3) flight control software; and (4) mating hardware, needed for docking or berthing operations. A discussion of how these factors affect vehicle design follows, addressing both active and passive/cooperative vehicles.

Numerical Optimization of the Position in Femoral Head of Proximal Locking Screws of Proximal Femoral Nail System; Biomechanical Study.

PubMed

Konya, Mehmet Nuri; Verim, Özgür

2017-09-29

Proximal femoral fracture rates are increasing due to osteoporosis and traffic accidents. Proximal femoral nails are routinely used in the treatment of these fractures in the proximal femur. To compare various combinations and to determine the ideal proximal lag screw position in pertrochanteric fractures (Arbeitsgemeinschaft für Osteosynthesefragen classification 31-A1) of the femur by using optimized finite element analysis. Biomechanical study. Computed tomography images of patients' right femurs were processed with Mimics. Afterwards a solid femur model was created with SolidWorks 2015 and transferred to ANSYS Workbench 16.0 for response surface optimization analysis which was carried out according to anterior-posterior (-10°proximal lag screw positions in the fracture region. The optimum position of the proximal lag screw was determined based on the von Mises stress values occurring on the fracture line. Initial analysis of the system was realized under the surgeon's normal positioning conditions (anterior-posterior, inferior-superior=0°; tip-apex distance=12 mm). The maximum and minimum (compression) von Mises stresses were found to be 438 MPa and 0.003 MPa, respectively, and risky stresses for the system occurred in the regions where the proximal lag screw passes through the proximal femoral nail hole, the small diameter portion of stem joints with a large diameter and lag screw mounts to the stem. The most suitable position of the proximal lag screw was found at the middle position of the tip-apex distance (20 mm) and femoral neck (anterior-posterior, inferior-superior=0°), according to von Mises compression stress values occurring on the fracture line. In our study, we couldn't find any correlation between proximal lag screw movement and tip-apex distance on stresses of the fracture surfaces, but the proximal lag screw

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

Modeling tunneling for the unconventional superconducting proximity effect

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zareapour, Parisa; Xu, Jianwei; Zhao, Shu Yang F.

Recently there has been reinvigorated interest in the superconducting proximity effect, driven by predictions of the emergence of Majorana fermions. To help guide this search, we have developed a phenomenological model for the tunneling spectra in anisotropic superconductor-normal metal proximity devices. We combine successful approaches used in s-wave proximity and standard d-wave tunneling to reproduce tunneling spectra in d-wave proximity devices, and clarify the origin of various features. Different variations of the pair potential are considered, resulting from the proximity-induced superconductivity. Furthermore, the effective pair potential felt by the quasiparticles is momentum-dependent in contrast to s-wave superconductors. The probabilities ofmore » reflection and transmission are calculated by solving the Bogoliubov equations. Our results are consistent with experimental observations of the unconventional proximity effect and provide important experimental parameters such as the size and length scale of the proximity induced gap, as well as the conditions needed to observe the reduced and full superconducting gaps.« less

Modeling tunneling for the unconventional superconducting proximity effect

DOE PAGES

Zareapour, Parisa; Xu, Jianwei; Zhao, Shu Yang F.; ...

2016-10-12

Recently there has been reinvigorated interest in the superconducting proximity effect, driven by predictions of the emergence of Majorana fermions. To help guide this search, we have developed a phenomenological model for the tunneling spectra in anisotropic superconductor-normal metal proximity devices. We combine successful approaches used in s-wave proximity and standard d-wave tunneling to reproduce tunneling spectra in d-wave proximity devices, and clarify the origin of various features. Different variations of the pair potential are considered, resulting from the proximity-induced superconductivity. Furthermore, the effective pair potential felt by the quasiparticles is momentum-dependent in contrast to s-wave superconductors. The probabilities ofmore » reflection and transmission are calculated by solving the Bogoliubov equations. Our results are consistent with experimental observations of the unconventional proximity effect and provide important experimental parameters such as the size and length scale of the proximity induced gap, as well as the conditions needed to observe the reduced and full superconducting gaps.« less

Optical proximity correction for anamorphic extreme ultraviolet lithography

NASA Astrophysics Data System (ADS)

Clifford, Chris; Lam, Michael; Raghunathan, Ananthan; Jiang, Fan; Fenger, Germain; Adam, Kostas

2017-10-01

The change from isomorphic to anamorphic optics in high numerical aperture (NA) extreme ultraviolet (EUV) scanners necessitates changes to the mask data preparation flow. The required changes for each step in the mask tape out process are discussed, with a focus on optical proximity correction (OPC). When necessary, solutions to new problems are demonstrated, and verified by rigorous simulation. Additions to the OPC model include accounting for anamorphic effects in the optics, mask electromagnetics, and mask manufacturing. The correction algorithm is updated to include awareness of anamorphic mask geometry for mask rule checking (MRC). OPC verification through process window conditions is enhanced to test different wafer scale mask error ranges in the horizontal and vertical directions. This work will show that existing models and methods can be updated to support anamorphic optics without major changes. Also, the larger mask size in the Y direction can result in better model accuracy, easier OPC convergence, and designs which are more tolerant to mask errors.

CFTR is restricted to a small population of high expresser cells that provide a forskolin-sensitive transepithelial Cl- conductance in the proximal colon of the possum, Trichosurus vulpecula.

PubMed

Fan, Shujun; Harfoot, Natalie; Bartolo, Ray C; Butt, A Grant

2012-04-01

The cystic fibrosis transmembrane conductance regulator (CFTR) is central to anion secretion in both the possum and eutherian small intestine. Here, we investigated its role in the possum proximal colon, which has novel transport properties compared with the eutherian proximal colon. Despite considerable CFTR expression, high doses of the CFTR activator forskolin (EC(50)≈10 μmol l(-1)) were required for a modest, CFTR-dependent increase in short-circuit current (I(sc)) in the proximal colon. Presumably, this is because CFTR is restricted to the apical membrane of a small population of CFTR high expresser (CHE) cells in the surface and upper crypt epithelium. Furthermore, although the forskolin-stimulated I(sc) was dependent on serosal Na(+), Cl(-) and HCO(3)(-), consistent with anion secretion, inhibition of the basolateral Na-K-2Cl(-) (NKCC1) or Na-HCO(3) (pNBCe1) cotransporters did not prevent it. Therefore, although NKCC1 and pNBCe1 are expressed in the colonic epithelium they do not appear to be expressed in CHE cells. At low doses (IC(50)≈1 μmol l(-1)), forskolin also decreased the transepithelial conductance (G(T)) of the colon through inhibition of a 4,4'-diisothiocyano-2,2'-stilbenedisulphonic acid-sensitive anion conductance in the basolateral membrane of the CHE cells. This conductance is arranged in series with CFTR in the CHE cells and, therefore, the CHE cells provide a transepithelial Cl(-) conductance for passive Cl(-) absorption across the epithelium. Inhibition of the basolateral Cl(-) conductance of the CHE cells by forskolin will inhibit Na(+) absorption by restricting the movement of its counter-ion Cl(-), assisting in the conversion of the tissue from an absorptive to a secretory state.

The proximal straight tubule (PST) basolateral cell membrane water channel: selectivity characteristics.

PubMed

Gutiérrez, A M; González, E; Echevarría, M; Hernández, C S; Whittembury, G

1995-02-01

Proximal straight tubules (PST) were dissected from rabbit kidneys, held by crimping pipettes in a chamber and bathed in a buffered isosmotic (295 mOsm/kg) solution containing 200 mM mannitol (MBS). Changes in tubule diameter were monitored on line with an inverted microscope, TV camera and image processor. The PST were then challenged for 20 sec with MBS made 35 mOsm/kg hyperosmotic by addition of either NaCl, KCl, mannitol (M), glycerol (G), ethylene glycol (E), glycine (g), urea (U), acetamide (A) or formamide (F). With NaCl, KCl, M, G, E, g, U, and A, tubules shrunk osmometrically within 0.5 sec and remained shrunk for as long as 20 sec without recovering their original volume (sometimes A showed some recovery). PST barely shrunk with F and quickly recovered their original volume. The permeability coefficients were 0 microns/sec (NaCl, M, g, E and U), 1 micron/sec (A), 84 microns/sec (F) and 0.02 micron/sec (G). The reflection coefficients sigma = 1.0 (NaCl, KCl, M, G, E, g and U), 0.95 (A) and 0.62 (F). Similar sigma values were obtained by substituting 200 mOsm/kg M in MBS by either NaCl, KCl, G, E, g, U, a or F. The olive oil/water partition coefficients are 5 (M), 15 (U), 85 (A) and 75 (F) (all x 10(-5)). Thus, part of F permeates the cell membrane through the lipid bilayer. The probing molecules van der Waals diameters are 7.4 x 8.2 x 12.0 (M), 3.6 x 5.2 x 5.4 (U), 3.8 x 5.2 x 5.4 (A) and (3.4 x 4.5 x 5.4 (F) A.(ABSTRACT TRUNCATED AT 250 WORDS)

Proximal opening wedge osteotomy with wedge-plate fixation compared with proximal chevron osteotomy for the treatment of hallux valgus: a prospective, randomized study.

PubMed

Glazebrook, Mark; Copithorne, Peter; Boyd, Gordon; Daniels, Timothy; Lalonde, Karl-André; Francis, Patricia; Hickey, Michael

2014-10-01

Hallux valgus with an increased intermetatarsal angle is usually treated with a proximal metatarsal osteotomy. The proximal chevron osteotomy is commonly used but is technically difficult. This study compares the proximal opening wedge osteotomy of the first metatarsal with the proximal chevron osteotomy for the treatment of hallux valgus with an increased intermetatarsal angle. This prospective, randomized multicenter (three-center) study was based on the clinical outcome scores of the Short Form-36, the American Orthopaedic Foot & Ankle Society forefoot questionnaire, and the visual analog scale for pain, activity, and patient satisfaction. Subjects were assessed prior to surgery and at three, six, and twelve months postoperatively. Surgeon preference was evaluated based on questionnaires and the operative times required for each procedure. No significant differences were found for any of the patients' clinical outcome measurements between the two procedures. The proximal opening wedge osteotomy was found to lengthen, and the proximal chevron osteotomy was found to shorten, the first metatarsal. The intermetatarsal angles improved (decreased) significantly, from 14.8° ± 3.2° to 9.1° ± 2.9 (mean and standard deviation) after a proximal opening wedge osteotomy and from 14.6° ± 3.9° to 11.3° ± 4.0° after a proximal chevron osteotomy (p < 0.05 for both). Operative time required for performing a proximal opening wedge osteotomy is similar to that required for performing a proximal chevron osteotomy (mean and standard deviation, 67.1 ± 16.5 minutes compared with 69.9 ± 18.6 minutes; p = 0.510). Opening wedge and proximal chevron osteotomies have comparable radiographic outcomes and comparable clinical outcomes for pain, satisfaction, and function. The proximal opening wedge osteotomy lengthens, and the proximal chevron osteotomy shortens, the first metatarsal. The proximal opening wedge osteotomy was subjectively less technically demanding and was

Ionic regulation of the biosynthesis of NaK-ATPase subunits.

PubMed

McDonough, A A; Tang, M J; Lescale-Matys, L

1990-07-01

In this review we have summarized the work of ourselves and others on ionic and hormonal regulation of synthesis of the sodium pump. No one central theme emerges from this summary. Rather, it appears that abundance can be regulated pre-translationally or posttranslationally. As reviewed recently, regulation of the expression of the beta glycoprotein subunit, which has no described enzymatic function, can regulate holoenzyme expression. In the kidney this is exemplified in our studies in LLC-PK1 cells and proximal tubule cells where pre-translational regulation of beta expression is key to increasing holoenzyme abundance, and also exemplified in the hypothyroid renal cortex where regulation of beta protein abundance post-translationally appears to impact the abundance of enzymatically active NaK-ATPase. Future studies in the field of ionic regulation of NaK-ATPase must be directed at elucidating the signals that mediate the response, and at how these signals alter the NaK-ATPase biosynthetic pathway from expression of alpha and beta genes, through to turnover of the mature NaK-ATPase heterodimer.

External and internal resin infiltration of natural proximal subsurface caries lesions: A valuable enhancement of the internal tunnel restoration.

PubMed

Kielbassa, Andrej M; Ulrich, Ina; Werth, Vanessa D; Schüller, Christoph; Frank, Wilhelm; Schmidl, Rita

2017-01-01

The aim of this ex-vivo study was to evaluate both the external and the internal penetration ability of a resin infiltrant into natural proximal and macroscopically intact white spot lesions, and to merge this approach with the internal tunnel preparation concept. 20 premolars and 20 molars with proximal subsurface lesions (ICDAS, code 2) and respective radiographic lesion depths extending into the middle third of dentin (D2 lesions) were selected and divided into two groups. Treatment needs were confirmed using digital imaging fiber-optic transillumination and laser fluorescence. Deproteinization (NaOCl; 2%) followed, and lesions of Group 1 (control; n = 20) were etched (HCl; 15%) and externally infiltrated (Icon). Accordingly, the specimens of Group 2 (n = 20) were treated with the resin infiltrant from external; then, internal Class I tunnels were prepared, lesions were internally infiltrated (Icon), and the occlusal cavities were restored (G-ænial Flo X) after etching (H3PO4 gel; 40%). Teeth were cut perpendicular to the proximal lesion surfaces, and percentage infiltrations were analyzed using confocal laser microscopy and a dedicated image manipulation program (GIMP). Regarding the external infiltration, no differences between both groups were detected (P = .114; Mann-Whitney). Additional internal application of the resin infiltrant significantly increased the percentage amount of enamel lesion infiltration (P < .0001; Wilcoxon). External and internal infiltration seem to complement the internal tunnel approach, thus remediating the drawbacks of the latter by occluding and stabilizing the porous areas of the proximal caries lesion, and preserving both the marginal ridge and the proximal contact area.

Early results for treatment of two- and three-part fractures of the proximal humerus using Contours PHP (proximal humeral plate).

PubMed

Biazzo, Alessio; Cardile, Carlo; Brunelli, Luca; Ragni, Paolo; Clementi, Daniele

2017-04-28

The management of displaced 2- and 3-part fractures of the proximal humerus is controversial, both in younger and in elderly patients. The purpose of this paper is to evaluate the functional results of the Contours Proximal Humerus Plate (OrthofixR, Bussolengo,Verona, Italy), for the treatment of displaced 2- and 3-part fractures of the proximal humerus. We retrospectively reviewed 55 patients with proximal humerus fractures, who underwent osteosynthesis with Contours Proximal Humerus Plate from December 2011 to March 2015. We had 21 patients with 2-part fractures and with an average age of 67.1 years and 34 patients with 3-part fractures, with average age of 63.6 years. The average union time was 3 months. The mean Constant score was 67 for 2-part fracture group and 64.9 for 3-part fracture group. The difference was not statistically significant (p = 0.18). The overall complication rate was 14.5 %. Six patients underwent additional surgery (10.9%). The most frequent major complication was secondary loss of reduction following varus collapse of the fracture (2 cases). In these patients, there was loss of medial hinge integrity due to impaction and osteoporosis. The placement of the main locking screw in the calcar area to provide inferomedial support is the rational of the Contours Proximal Humerus Plate. Osteosynthesis with Contours Proximal Humerus Plate is a safe system for treating displaced 2- and 3-part fractures of the proximal humerus, with good functional results and complication rates comparable to those reported in the literature.

Proximal Hamstring Tendinosis and Partial Ruptures.

PubMed

Startzman, Ashley N; Fowler, Oliver; Carreira, Dominic

2017-07-01

Proximal hamstring tendinosis and partial hamstring origin ruptures are painful conditions of the proximal thigh and hip that may occur in the acute, chronic, or acute on chronic setting. Few publications exist related to their diagnosis and management. This systematic review discusses the incidence, treatment, and prognosis of proximal hamstring tendinosis and partial hamstring ruptures. Conservative treatment measures include nonsteroidal anti-inflammatory drugs, physical therapy, rest, and ice. If these measures fail, platelet-rich plasma or shockwave therapy may be considered. When refractory to conservative management, these injuries may be treated with surgical debridement and hamstring reattachment. [Orthopedics. 2017; 40(4):e574-e582.]. Copyright 2017, SLACK Incorporated.

14 CFR 135.153 - Ground proximity warning 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 system. 135.153... Equipment § 135.153 Ground proximity warning system. (a) No person may operate a turbine-powered airplane... equipped with an approved ground proximity warning system. (b) [Reserved] (c) For a system required by this...

14 CFR 135.153 - Ground proximity warning system.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Ground proximity warning system. 135.153... Equipment § 135.153 Ground proximity warning system. (a) No person may operate a turbine-powered airplane... equipped with an approved ground proximity warning system. (b) [Reserved] (c) For a system required by this...

Antenatal betamethasone attenuates the angiotensin-(1-7)-Mas receptor-nitric oxide axis in isolated proximal tubule cells.

PubMed

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

2017-06-01

We previously reported a sex-specific effect of antenatal treatment with betamethasone (Beta) on sodium (Na + ) excretion in adult sheep whereby treated males but not females had an attenuated natriuretic response to angiotensin-(1-7) [Ang-(1-7)]. The present study determined the Na + uptake and nitric oxide (NO) response to low-dose Ang-(1-7) (1 pM) in renal proximal tubule cells (RPTC) from adult male and female sheep antenatally exposed to Beta or vehicle. Data were expressed as percentage of basal uptake or area under the curve for Na + or percentage of control for NO. Male Beta RPTC exhibited greater Na + uptake than male vehicle cells (433 ± 28 vs. 330 ± 26%; P < 0.05); however, Beta exposure had no effect on Na + uptake in the female cells (255 ± 16 vs. 255 ± 14%; P > 0.05). Ang-(1-7) significantly inhibited Na + uptake in RPTC from vehicle male (214 ± 11%) and from both vehicle (190 ± 14%) and Beta (209 ± 11%) females but failed to attenuate Na + uptake in Beta male cells. Beta exposure also abolished stimulation of NO by Ang-(1-7) in male but not female RPTC. Both the Na + and NO responses to Ang-(1-7) were blocked by Mas receptor antagonist d-Ala 7 -Ang-(1-7). We conclude that the tubular Ang-(1-7)-Mas-NO pathway is attenuated in males and not females by antenatal Beta exposure. Moreover, since primary cultures of RPTC retain both the sex and Beta-induced phenotype of the adult kidney in vivo they appear to be an appropriate cell model to examine the effects of fetal programming on Na + handling by the renal tubules. Copyright © 2017 the American Physiological Society.

Loss of tubular creatinine secretion as the only sign of tubular proximal cell dysfunction in light chain proximal tubulopathy: A case report.

PubMed

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

2016-06-01

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 CrEDTA. 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.

Preventing Proximal Adjacent Level Kyphosis With Strap Stabilization.

PubMed

Zaghloul, Khaled M; Matoian, Brett J; Denardin, Nicholas B; Patel, Vikas V

2016-07-01

A substantial proportion of patients develop proximal junctional kyphosis following spinal surgery. To combat this postoperative change, several techniques have focused on maintaining the structural integrity of adjacent spinal levels and adapting the proximal end of the fusion construct to accommodate the increased mechanical stressors produced by long spinal fusion. The use of Mersilene tape (Ethicon, Somerville, New Jersey) for spine and orthopedic surgery is well documented, although considerably less is known about its use for preventing proximal junctional kyphosis. This article describes a proposed technique using Mersilene tape to provide a check-rein strap stabilization at the proximal end of fusion constructs. Initial data suggest that use of this technique may prevent formation of proximal junctional kyphosis. [Orthopedics. 2016; 39(4):e794-e799.]. Copyright 2016, SLACK Incorporated.

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…

Prosthetic replacement for proximal humeral fractures.

PubMed

Kontakis, George; Tosounidis, Theodoros; Galanakis, Ioannis; Megas, Panagiotis

2008-12-01

The ideal management of complex proximal humeral fractures continues to be debatable. Evolution of proximal humeral fracture management, during the past decade, led to the implementation of many innovations in surgical treatment. Even though the pendulum of treatment seems to swing towards new trends such as locked plating, hemiarthroplasty remains a valid and reliable option that serves the patient's needs well. Hemiarthroplasty is indicated for complex proximal humeral fractures in elderly patients with poor bone stock and when internal fixation is difficult or unreliable. Hemiarthroplasty provides a better result when it is performed early post-injury. Stem height, retroversion and tuberosity positioning are technical aspects of utmost importance. Additionally reverse total shoulder arthroplasty is an alternative new modality that can be used as a primary solution in selected patients with proximal humeral fracture treatment. Failed hemiarthroplasty and fracture sequelae can be successfully managed with reverse total shoulder arthroplasty. Individual decision-making and tailored treatment that takes into consideration the personality of the fracture and the patient's characteristics should be used.

Proximal tibial osteotomy. A survivorship analysis.

PubMed

Ritter, M A; Fechtman, R A

1988-01-01

Proximal tibial osteotomy is generally accepted as a treatment for the patient with unicompartmental arthritis. However, a few reports of the long-term results of this procedure are available in the literature, and none have used the technique known as survivorship analysis. This technique has an advantage over conventional analysis because it does not exclude patients for inadequate follow-up, loss to follow-up, or patient death. In this study, survivorship analysis was applied to 78 proximal tibial osteotomies, performed exclusively by the senior author for the correction of a preoperative varus deformity, and a survival curve was constructed. It was concluded that the reliable longevity of the proximal tibial osteotomy is approximately 6 years.

The theoretical simulation on electrostatic distribution of 1st proximity region in proximity focusing low-light-level image intensifier

NASA Astrophysics Data System (ADS)

Zhang, Liandong; Bai, Xiaofeng; Song, De; Fu, Shencheng; Li, Ye; Duanmu, Qingduo

2015-03-01

Low-light-level night vision technology is magnifying low light level signal large enough to be seen by naked eye, which uses the photons - photoelectron as information carrier. Until the micro-channel plate was invented, it has been possibility for the realization of high performance and miniaturization of low-light-level night vision device. The device is double-proximity focusing low-light-level image intensifier which places a micro-channel plate close to photocathode and phosphor screen. The advantages of proximity focusing low-light-level night vision are small size, light weight, small power consumption, no distortion, fast response speed, wide dynamic range and so on. It is placed parallel to each other for Micro-channel plate (both sides of it with metal electrode), the photocathode and the phosphor screen are placed parallel to each other. The voltage is applied between photocathode and the input of micro-channel plate when image intensifier works. The emission electron excited by photo on the photocathode move towards to micro-channel plate under the electric field in 1st proximity focusing region, and then it is multiplied through the micro-channel. The movement locus of emission electrons can be calculated and simulated when the distributions of electrostatic field equipotential lines are determined in the 1st proximity focusing region. Furthermore the resolution of image tube can be determined. However the distributions of electrostatic fields and equipotential lines are complex due to a lot of micro-channel existing in the micro channel plate. This paper simulates electrostatic distribution of 1st proximity region in double-proximity focusing low-light-level image intensifier with the finite element simulation analysis software Ansoft maxwell 3D. The electrostatic field distributions of 1st proximity region are compared when the micro-channel plates' pore size, spacing and inclination angle ranged. We believe that the electron beam movement

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.

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.

MRI appearance of the proximal hamstring tendons in patients with and without symptomatic proximal hamstring tendinopathy.

PubMed

De Smet, Arthur A; Blankenbaker, Donna G; Alsheik, Nila H; Lindstrom, Mary J

2012-02-01

The purpose of our study was to determine if six MRI findings of the proximal hamstrings differ in frequency in hamstrings with and without symptoms of tendinopathy. We reviewed the MRI examinations of 118 consecutive patients who had undergone pelvis MRI and evaluation by a musculoskeletal clinical specialist. The proximal hamstrings were evaluated at four consecutive axial locations for tendon size, internal T1 and T2 signal, peritendinous T2 signal, and ischial tuberosity edema. Statistical analysis was performed to determine the association of the MRI findings with symptomatic hamstring tendinopathy. Twenty-one patients had a clinical diagnosis of unilateral proximal hamstring tendinopathy. The mean width or anteroposterior size was significantly larger in symptomatic hamstrings at all three proximal levels (p = 0.002-0.040). More than 90% of hamstring tendons had increased internal T1 or T2 signal that was not associated with hamstring symptoms. Both hamstrings with and without symptoms of tendinopathy had peritendinous T2 signal, but this was significantly more common in hamstrings with tendinopathy symptoms at the three most distal levels (p = 0.001-0.041). Ischial tuberosity edema and a feathery appearance of the peritendinous T2 signal distally were significantly more common in symptomatic hamstrings (p = 0.004 and 0.001, respectively). Increased T1 and T2 signal is commonly seen within the proximal hamstrings but is not associated with symptoms of hamstring tendinopathy. Increased tendon size, peritendinous T2 signal with a distal feathery appearance, and ischial tuberosity edema are significantly associated with symptomatic hamstring tendinopathy but can be seen in asymptomatic individuals.

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.

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.

Acute renal proximal tubule alterations during induced metabolic crises in a mouse model of glutaric aciduria type 1.

PubMed

Thies, Bastian; Meyer-Schwesinger, Catherine; Lamp, Jessica; Schweizer, Michaela; Koeller, David M; Ullrich, Kurt; Braulke, Thomas; Mühlhausen, Chris

2013-10-01

The metabolic disorder glutaric aciduria type 1 (GA1) is caused by deficiency of the mitochondrial glutaryl-CoA dehydrogenase (GCDH), leading to accumulation of the pathologic metabolites glutaric acid (GA) and 3-hydroxyglutaric acid (3OHGA) in blood, urine and tissues. Affected patients are prone to metabolic crises developing during catabolic conditions, with an irreversible destruction of striatal neurons and a subsequent dystonic-dyskinetic movement disorder. The pathogenetic mechanisms mediated by GA and 3OHGA have not been fully characterized. Recently, we have shown that GA and 3OHGA are translocated through membranes via sodium-dependent dicarboxylate cotransporter (NaC) 3, and organic anion transporters (OATs) 1 and 4. Here, we show that induced metabolic crises in Gcdh(-/-) mice lead to an altered renal expression pattern of NaC3 and OATs, and the subsequent intracellular GA and 3OHGA accumulation. Furthermore, OAT1 transporters are mislocalized to the apical membrane during metabolic crises accompanied by a pronounced thinning of proximal tubule brush border membranes. Moreover, mitochondrial swelling and increased excretion of low molecular weight proteins indicate functional tubulopathy. As the data clearly demonstrate renal proximal tubule alterations in this GA1 mouse model during induced metabolic crises, we propose careful evaluation of renal function in GA1 patients, particularly during acute crises. Further studies are needed to investigate if these findings can be confirmed in humans, especially in the long-term outcome of affected patients. Copyright © 2013 Elsevier B.V. All rights reserved.

Proximity correction of high-dosed frame with PROXECCO

NASA Astrophysics Data System (ADS)

Eisenmann, Hans; Waas, Thomas; Hartmann, Hans

1994-05-01

Usefulness of electron beam lithography is strongly related to the efficiency and quality of methods used for proximity correction. This paper addresses the above issue by proposing an extension to the new proximity correction program PROXECCO. The combination of a framing step with PROXECCO produces a pattern with a very high edge accuracy and still allows usage of the fast correction procedure. Making a frame with a higher dose imitates a fine resolution correction where the coarse part is disregarded. So after handling the high resolution effect by means of framing, an additional coarse correction is still needed. Higher doses have a higher contribution to the proximity effect. This additional proximity effect is taken into account with the help of the multi-dose input of PROXECCO. The dose of the frame is variable, depending on the deposited energy coming from backscattering of the proximity. Simulation proves the very high edge accuracy of the applied method.

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

Use and Understanding of the Proximate Status Indication in Traffic Displays

DOT National Transportation Integrated Search

2011-10-16

Traffic Collision Avoidance System (TCAS) traffic displays use symbol fill to distinguish proximate from non-proximate targets, where proximate targets are within a specified range and altitude of ownship, and non-proximate targets are ou...

Proximal and distal muscle fatigue differentially affect movement coordination

PubMed Central

Cowley, Jeffrey C.

2017-01-01

Muscle fatigue can cause people to change their movement patterns and these changes could contribute to acute or overuse injuries. However, these effects depend on which muscles are fatigued. The purpose of this study was to determine the differential effects of proximal and distal upper extremity muscle fatigue on repetitive movements. Fourteen subjects completed a repetitive ratcheting task before and after a fatigue protocol on separate days. The fatigue protocol either fatigued the proximal (shoulder flexor) or distal (finger flexor) muscles. Pre/Post changes in trunk, shoulder, elbow, and wrist kinematics were compared to determine how proximal and distal fatigue affected multi-joint movement patterns and variability. Proximal fatigue caused a significant increase (7°, p < 0.005) in trunk lean and velocity, reduced humeral elevation (11°, p < 0.005), and increased elbow flexion (4°, p < 0.01). In contrast, distal fatigue caused small but significant changes in trunk angles (2°, p < 0.05), increased velocity of wrench movement relative to the hand (17°/s, p < 0.001), and earlier wrist extension (4%, p < 0.005). Movement variability increased at proximal joints but not distal joints after both fatigue protocols (p < 0.05). Varying movements at proximal joints may help people adapt to fatigue at either proximal or distal joints. The identified differences between proximal and distal muscle fatigue adaptations could facilitate risk assessment of occupational tasks. PMID:28235005

In vivo study of transepithelial potential difference (TEPD) in proximal convoluted tubules of rat kidney by synchronization modulation electric field.

PubMed

Clausell, Mathis; Fang, Zhihui; Chen, Wei

2014-07-01

Synchronization modulation (SM) electric field has been shown to effectively activate function of Na(+)/K(+) pumps in various cells and tissues, including skeletal muscle cells, cardiomyocyte, monolayer of cultured cell line, and peripheral blood vessels. We are now reporting the in vivo studies in application of the SM electric field to kidney of living rats. The field-induced changes in the transepithelial potential difference (TEPD) or the lumen potential from the proximal convoluted tubules were monitored. The results showed that a short time (20 s) application of the SM electric field can significantly increase the magnitude of TEPD from 1-2 mV to about 20 mV. The TEPD is an active potential representing the transport current of the Na/K pumps in epithelial wall of renal tubules. This study showed that SM electric field can increase TEPD by activation of the pump molecules. Considering renal tubules, many active transporters are driven by the Na(+) concentration gradient built by the Na(+)/K(+) pumps, activation of the pump functions and increase in the magnitude of TEPD imply that the SM electric field may improve reabsorption functions of the renal tubules.

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.

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.

Longitudinal Proximity Effect, Lateral Inverse Proximity Effect, and Nonequilibrium Superconductivity in Transition-edge Sensors

NASA Technical Reports Server (NTRS)

Sadleir, John E.

2010-01-01

We have recently shown that normal-metal/superconductor (N/S) bilayer TESs (superconducting Transition-Edge Sensors) exhibit weak-link behavior. Our measurements were explained in terms of a longitudinal proximity effect model in which superconducting order from the higher transition temperature leads is induced into the TES bilayer plane over remarkably long distances (up to 290 micron). Here we extend our understanding to include TESs with added noise-mitigating normal-metal structures (N structures). We explain our results of an effect converse to the longitudinal proximity effect (LoPE), the lateral inverse proximity effect (LaiPE), for which the order parameter in the N/S bilayer is reduced due to the neighboring N structures. We present resistance and critical current measurements as a function of temperature and magnetic field taken on square Mo/Au bilayer TESs with lengths ranging from 8 to 130 micron 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 temperature scale approximately as the inverse square of the in-plane N-structure separation distance, without appreciable broadening of the transition width. We find TESs with added Au structures 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 also present evidence for nonequilbrium superconductivity and estimate a quasiparticle lifetime of 1.8 x 10(exp -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

Longitudinal Proximity Effect, Lateral Inverse Proximity Effect, and Nonequilibrium Superconductivity in Transition-Edge Sensors

NASA Technical Reports Server (NTRS)

Sadleir, John E.

2010-01-01

We have recently shown that normal-metal/superconductor (N /S) bilayer TESs (superconducting Transition-Edge Sensors) exhibit weak-link behavior. Our measurements were explained in terms of a longitudinal proximity effect model in which superconducting order from the higher transition temperature leads is induced into the TES bilayer plane over remarkably long distances (up to 290 micron). Here we extend our understanding to include TESs with added noise-mitigating normal-metal structures (N structures). We explain our results in terms of an effect converse to the longitudinal proximity effect (LoPE), the lateral inverse proximity effect (LaiPE), for which the order parameter in the N /S bilayer is reduced due to the neighboring N structures. We present resistance and critical current measurements as a function of temperature and magnetic field taken on square Mo/Au bilayer TESs with lengths ranging from 8 to 130 micron 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 find TESs with added Au structures 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 also present evidence for nonequilbrium superconductivity and estimate a quasiparticle lifetime of 1.8 x 10(exp -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.

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. Copyright 2015 by the American Academy of Orthopaedic Surgeons.

Dual pathology proximal median nerve compression of the forearm.

PubMed

Murphy, Siun M; Browne, Katherine; Tuite, David J; O'Shaughnessy, Michael

2013-12-01

We report an unusual case of synchronous pathology in the forearm- the coexistence of a large lipoma of the median nerve together with an osteochondroma of the proximal ulna, giving rise to a dual proximal median nerve compression. Proximal median nerve compression neuropathies in the forearm are uncommon compared to the prevalence of distal compression neuropathies (eg Carpal Tunnel Syndrome). Both neural fibrolipomas (Refs. 1,2) and osteochondromas of the proximal ulna (Ref. 3) in isolation are rare but well documented. Unlike that of a distal compression, a proximal compression of the median nerve will often have a definite cause. Neural fibrolipoma, also called fibrolipomatous hamartoma are rare, slow-growing, benign tumours of peripheral nerves, most often occurring in the median nerve of younger patients. To our knowledge, this is the first report of such dual pathology in the same forearm, giving rise to a severe proximal compression of the median nerve. In this case, the nerve was being pushed anteriorly by the osteochondroma, and was being compressed from within by the intraneural lipoma. This unusual case highlights the advantage of preoperative imaging as part of the workup of proximal median nerve compression. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Differences between naïve and expert observers’ vergence and accommodative responses to a range of targets

PubMed Central

Horwood, Anna M; Riddell, Patricia M

2015-01-01

Purpose Vergence and accommodation studies often use adult participants with experience of vision science. Reports of infant and clinical responses are generally more variable and of lower gain, with the implication that differences lie in immaturity or sub-optimal clinical characteristics but expert /naïve differences are rarely considered or quantified. Methods Sixteen undergraduates, naïve to vision science were individually matched by age, visual acuity, refractive error, heterophoria, stereoacuity and near point of accommodation to 2nd & 3rd year orthoptics and optometry undergraduates (“experts”). Accommodation and vergence responses were assessed to targets moving between 33cm, 50 cm, 1m and 2m using a haploscopic device incorporating a PlusoptiX SO4 autorefractor. Disparity, blur and looming cues were separately available or minimised in all combinations. Instruction set was minimal. Results In all cases, vergence and accommodation response slopes (gain) were steeper and closer to 1.0 in the expert group (p=0.001), with the largest expert /naïve differences for both vergence and accommodation being for near targets (p=0.012). For vergence, the differences between expert and naïve response slopes increased with increasingly open-loop targets (linear trend p=0.025). Although we predicted that proximal cues would drive additional response in the experts, the proximity-only cue was the only condition that showed no statistical effect of experience. Conclusions Expert observers provide more accurate responses to near target demand than closely matched naïve observers. We suggest that attention, practice, voluntary and proprioceptive effects may enhance responses in experienced participants when compared to a more typical general population. Differences between adult reports and the developmental and clinical literature may partially reflect expert / naïve effects, as well as developmental change. If developmental and clinical studies are to be compared

Orbiter/payload proximity operations: Lateral approach technique

NASA Technical Reports Server (NTRS)

Bell, J. A.; Jones, H. L.; Mcadoo, S. F.

1977-01-01

The lateral approach is presented for proximity operations associated with the retrieval of free flying payloads. An out of plane final approach emphasizing onboard software support is recommended for all except the latter segment of the final approach in which manual control is considered mandatory. An overall assessment of various candidate proximity operations techniques are made.

PROXIMAL: a method for Prediction of Xenobiotic Metabolism.

PubMed

Yousofshahi, Mona; Manteiga, Sara; Wu, Charmian; Lee, Kyongbum; Hassoun, Soha

2015-12-22

Contamination of the environment with bioactive chemicals has emerged as a potential public health risk. These substances that may cause distress or disease in humans can be found in air, water and food supplies. An open question is whether these chemicals transform into potentially more active or toxic derivatives via xenobiotic metabolizing enzymes expressed in the body. We present a new prediction tool, which we call PROXIMAL (Prediction of Xenobiotic Metabolism) for identifying possible transformation products of xenobiotic chemicals in the liver. Using reaction data from DrugBank and KEGG, PROXIMAL builds look-up tables that catalog the sites and types of structural modifications performed by Phase I and Phase II enzymes. Given a compound of interest, PROXIMAL searches for substructures that match the sites cataloged in the look-up tables, applies the corresponding modifications to generate a panel of possible transformation products, and ranks the products based on the activity and abundance of the enzymes involved. PROXIMAL generates transformations that are specific for the chemical of interest by analyzing the chemical's substructures. We evaluate the accuracy of PROXIMAL's predictions through case studies on two environmental chemicals with suspected endocrine disrupting activity, bisphenol A (BPA) and 4-chlorobiphenyl (PCB3). Comparisons with published reports confirm 5 out of 7 and 17 out of 26 of the predicted derivatives for BPA and PCB3, respectively. We also compare biotransformation predictions generated by PROXIMAL with those generated by METEOR and Metaprint2D-react, two other prediction tools. PROXIMAL can predict transformations of chemicals that contain substructures recognizable by human liver enzymes. It also has the ability to rank the predicted metabolites based on the activity and abundance of enzymes involved in xenobiotic transformation.

Fracture line morphology of complex proximal humeral fractures.

PubMed

Hasan, Afsana P; Phadnis, Joideep; Jaarsma, Ruurd L; Bain, Gregory I

2017-10-01

The aim of this study was to assess proximal humeral fracture patterns using 3-dimensional computed tomography images and relate them to the normal osseous landmarks and soft-tissue attachments. Forty-eight 3-dimensional computed tomography scans of proximal humeral fractures were retrospectively collected, and the fractures were transcribed onto proximal humeral templates. We analyzed the common location and orientation of the fracture lines, with a focus on fractures of the articular surface, tuberosities, metaphysis, and proximal diaphysis. These fractures were compared with the attachments of the rotator cuff and glenohumeral capsule. Fifty-two percent of the fractures involved the articular surface. No fractures passed through the bicipital groove, and fractures were more commonly found on the posterior lesser tuberosity and on the anterior greater tuberosity, coinciding with the intervals between the rotator cuff tendon insertions. Intracapsular fractures of the calcar were more common (68%) than extracapsular fractures (32%). On the anterolateral aspect of the proximal humerus, fractures radiated from the articular margin, vertically down through the tuberosity zone between the rotator cuff footprints, meeting horizontally oriented fractures in the metaphyseal zone. On the posterior aspect, vertical fractures from the tuberosity zone continued downward to the metaphyseal zone adjacent to the infraspinatus and teres minor footprints. Fractures of the proximal humerus follow characteristic patterns. Fractures frequently split the greater tuberosity and are closely related to the intervals of the rotator cuff attachments. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

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.

Adenosine regulates CD8 T-cell priming by inhibition of membrane-proximal T-cell receptor signalling

PubMed Central

Linnemann, Carsten; Schildberg, Frank A; Schurich, Anna; Diehl, Linda; Hegenbarth, Silke I; Endl, Elmar; Lacher, Svenja; Müller, Christa E; Frey, Jürgen; Simeoni, Luca; Schraven, Burkhart; Stabenow, Dirk; Knolle, Percy A

2009-01-01

Adenosine is a well-described anti-inflammatory modulator of immune responses within peripheral tissues. Extracellular adenosine accumulates in inflamed and damaged tissues and inhibits the effector functions of various immune cell populations, including CD8 T cells. However, it remains unclear whether extracellular adenosine also regulates the initial activation of naïve CD8 T cells by professional and semi-professional antigen-presenting cells, which determines their differentiation into effector or tolerant CD8 T cells, respectively. We show that adenosine inhibited the initial activation of murine naïve CD8 T cells after αCD3/CD28-mediated stimulation. Adenosine caused inhibition of activation, cytokine production, metabolic activity, proliferation and ultimately effector differentiation of naïve CD8 T cells. Remarkably, adenosine interfered efficiently with CD8 T-cell priming by professional antigen-presenting cells (dendritic cells) and semi-professional antigen-presenting cells (liver sinusoidal endothelial cells). Further analysis of the underlying mechanisms demonstrated that adenosine prevented rapid tyrosine phosphorylation of the key kinase ZAP-70 as well as Akt and ERK1/2 in naïve αCD3/CD28-stimulated CD8 cells. Consequently, αCD3/CD28-induced calcium-influx into CD8 cells was reduced by exposure to adenosine. Our results support the notion that extracellular adenosine controls membrane-proximal T-cell receptor signalling and thereby also differentiation of naïve CD8 T cells. These data raise the possibility that extracellular adenosine has a physiological role in the regulation of CD8 T-cell priming and differentiation in peripheral organs. PMID:19740334

Adenosine regulates CD8 T-cell priming by inhibition of membrane-proximal T-cell receptor signalling.

PubMed

Linnemann, Carsten; Schildberg, Frank A; Schurich, Anna; Diehl, Linda; Hegenbarth, Silke I; Endl, Elmar; Lacher, Svenja; Müller, Christa E; Frey, Jürgen; Simeoni, Luca; Schraven, Burkhart; Stabenow, Dirk; Knolle, Percy A

2009-09-01

Adenosine is a well-described anti-inflammatory modulator of immune responses within peripheral tissues. Extracellular adenosine accumulates in inflamed and damaged tissues and inhibits the effector functions of various immune cell populations, including CD8 T cells. However, it remains unclear whether extracellular adenosine also regulates the initial activation of naïve CD8 T cells by professional and semi-professional antigen-presenting cells, which determines their differentiation into effector or tolerant CD8 T cells, respectively. We show that adenosine inhibited the initial activation of murine naïve CD8 T cells after alphaCD3/CD28-mediated stimulation. Adenosine caused inhibition of activation, cytokine production, metabolic activity, proliferation and ultimately effector differentiation of naïve CD8 T cells. Remarkably, adenosine interfered efficiently with CD8 T-cell priming by professional antigen-presenting cells (dendritic cells) and semi-professional antigen-presenting cells (liver sinusoidal endothelial cells). Further analysis of the underlying mechanisms demonstrated that adenosine prevented rapid tyrosine phosphorylation of the key kinase ZAP-70 as well as Akt and ERK1/2 in naïve alphaCD3/CD28-stimulated CD8 cells. Consequently, alphaCD3/CD28-induced calcium-influx into CD8 cells was reduced by exposure to adenosine. Our results support the notion that extracellular adenosine controls membrane-proximal T-cell receptor signalling and thereby also differentiation of naïve CD8 T cells. These data raise the possibility that extracellular adenosine has a physiological role in the regulation of CD8 T-cell priming and differentiation in peripheral organs.

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

PubMed

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

1999-06-01

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

Regulation of renal NaPi-2 expression and tubular phosphate reabsorption by growth hormone in the juvenile rat.

PubMed

Woda, Craig B; Halaihel, Nabil; Wilson, Paul V; Haramati, Aviad; Levi, Moshe; Mulroney, Susan E

2004-07-01

Growth hormone (GH) is an important factor in the developmental adaptation to enhance P(i) reabsorption; however, the nephron sites and mechanisms by which GH regulates renal P(i) uptake remain unclear and are the focus of the present study. Micropuncture experiments were performed after acute thyroparathyroidectomy in the presence and absence of parathyroid hormone (PTH) in adult (14- to 17-wk old), juvenile (4-wk old), and GH-suppressed juvenile male rats. While the phosphaturic effect of PTH was blunted in the juvenile rat compared with the adult, suppression of GH in the juvenile restored fractional P(i) excretion to adult levels. In the presence or absence of PTH, GH suppression in the juvenile rat caused a significant increase in the fractional P(i) delivery to the late proximal convoluted (PCT) and early distal tubule, so that delivery was not different from that in adults. These data were confirmed by P(i) uptake studies into brush-border membrane (BBM) vesicles. Immunofluorescence studies indicate increased BBM type IIa NaP(i) cotransporter (NaPi-2) expression in the juvenile compared with adult rat, and GH suppression reduced NaPi-2 expression to levels observed in the adult. GH replacement in the [N-acetyl-Tyr(1)-d-Arg(2)]-GRF-(1-29)-NH(2)-treated juveniles restored high NaPi-2 expression and P(i) uptake. Together, these novel results demonstrate that the presence of GH in the juvenile animal is crucial for the early developmental upregulation of BBM NaPi-2 and, most importantly, describe the enhanced P(i) reabsorption along the PCT and proximal straight nephron segments in the juvenile rat.

Ion transport in proximal colon of the rat. Sodium depletion stimulates neutral sodium chloride absorption.

PubMed Central

Foster, E S; Budinger, M E; Hayslett, J P; Binder, H J

1986-01-01

The model of sodium and chloride transport proposed for the colon is based on studies performed in the distal segment and tacitly assumes that ion transport is similar throughout the colon. In rat distal colon, neutral sodium-chloride absorption accounts for the major fraction of overall sodium absorption and aldosterone stimulates electrogenic, amiloride-sensitive sodium absorption. Since we have demonstrated qualitative differences in potassium transport in proximal and distal segments of rat colon, unidirectional 22Na and 36Cl fluxes were performed under short-circuit conditions across isolated proximal colon of control and sodium-depleted rats with secondary hyperaldosteronism. In the control group, net sodium absorption (JNanet) (7.4 +/- 0.5 mu eq/h . cm2) was greater than Isc (1.4 +/- 0.1 mu eq/h . cm2), and JClnet was 0 in Ringer solution. Residual flux (JR) was -5.2 +/- 0.5 mu eq/h . cm2 consistent with hydrogen ion secretion suggesting that neutral sodium absorption may represent sodium-hydrogen exchange. 1 mM mucosal amiloride, which inhibits sodium-hydrogen exchange in other epithelia, produced comparable decreases in JNanet and JR (4.1 +/- 0.6 and 3.2 +/- 0.6 mu eq/h . cm2, respectively) without a parallel fall in Isc. Sodium depletion stimulated JNanet, JClnet, and Isc by 7.0 +/- 1.4, 6.3 +/- 1.9, and 0.8 +/- 0.2 mu eq/h . cm2, respectively, and 1 mM amiloride markedly inhibited JNanet and JClnet by 6.0 +/- 1.1 and 4.0 +/- 1.6 mu eq/h . cm2, respectively, with only a minimal reduction in Isc. Conclusions: the predominant neutral sodium-absorptive mechanism in proximal colon is sodium-hydrogen exchange. Sodium depletion stimulates electroneutral chloride-dependent sodium absorption (most likely as a result of increasing sodium-hydrogen and chloride-bicarbonate exchanges), not electrogenic chloride-independent sodium transport. The model of ion transport in the proximal colon is distinct from that of the distal colon. PMID:2418060

The office candy dish: proximity's influence on estimated and actual consumption.

PubMed

Wansink, B; Painter, J E; Lee, Y-K

2006-05-01

Although there is increasing interest in how environmental factors influence food intake, there are mixed results and misunderstandings of how proximity and visibility influence consumption volume and contribute to obesity. The objective of this paper is to examine two questions: first, how does the proximity and salience of a food influence consumption volume? Second, are proximate foods consumed more frequently because they are proximate, or are they consumed more frequently because people lose track of how much they eat? The 4-week study involved the chocolate candy consumption of 40 adult secretaries. The study utilized a 2 x 2 within-subject design where candy proximity was crossed with visibility. Proximity was manipulated by placing the chocolates on the desk of the participant or 2 m from the desk. Visibility was manipulated by placing the chocolates in covered bowls that were either clear or opaque. Chocolates were replenished each evening, and placement conditions were rotated every Monday. Daily consumption was noted and follow-up questionnaires were distributed and analyzed. There were main effects for both proximity and visibility. People ate an average of 2.2 more candies each day when they were visible, and 1.8 candies more when they were proximately placed on their desk vs 2 m away. It is important to note, however, that there was a significant tendency for participants to consistently underestimate their daily consumption of proximately placed candies (-0.9) and overestimate their daily consumption of less proximately placed candies (+0.5). These results show that the proximity and visibility of a food can consistently increase an adult's consumption of it. In addition, these results suggest that people may be biased to overestimate the consumption of foods that are less proximate, and to underestimate those that are more proximate. Knowing about these deviation tendencies is important for those attempting effectively monitor their consumption of

Reduced Spin Hall Effects from Magnetic Proximity.

DOE PAGES

Zhang, Wei; Jungfleisch, Matthias B.; Jiang, Wanjun; ...

2015-03-26

We investigate temperature-dependent spin pumping and inverse spin Hall effects in thin Pt and Pd in contact with Permalloy. Our experiments show a decrease of the spin Hall effect with decreasing temperature, which is attributed to a temperature-dependent proximity effect. The spin Hall angle decreases from 0.086 at room temperature to 0.042 at 10 K for Pt and is nearly negligible at 10 K for Pd. By first-principle calculations, we show that the spin Hall conductivity indeed reduces by increasing the proximity-induced spin magnetic moments for both Pt and Pd. This work highlights the important role of proximity-induced magnetic orderingmore » to spin Hall phenomena in Pt and Pd.« less

Fiber-optic proximity sensor

NASA Technical Reports Server (NTRS)

Bejczy, A. K.; Hermann, W. A.; Primus, H. C.

1980-01-01

Proximity sensor for mechanical hand of remote manipulator incorporates fiber optics to conduct signals between light source and light detector. Fiber optics are not prone to noise from electromagnetic interference and radio-frequency interference as are sensors using long electrical cables.

Dual-Fiberoptic Microcantilever Proximity Sensor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goedeke, S.M.

2001-08-08

Microcantilevers are key components of many Micro-Electro-Mechanical Systems (MEMS) and Micro-Optical-Electro-Mechanical Systems (MOEMS) because slight changes to them physically or chemically lead to changes in mechanical characteristics. An inexpensive dual-fiberoptic microcantilever proximity sensor and model to predict its performance are reported here. Motion of a magnetic-material-coated cantilever is the basis of a system under development for measuring magnetic fields. The dual fiber proximity sensor will be used to monitor the motion of the cantilever. The specific goal is to sense induction fields produced by a current carrying conductor. The proximity sensor consists of two fibers side by side with claddingsmore » in contact. The fiber core diameter, 50 microns, and cladding thickness, 10 microns, are as small as routinely available commercially with the exception of single mode fiber. Light is launched into one fiber from a light-emitting diode (LED). It emerges from that fiber and reflects from the cantilever into the adjacent receiving fiber connected to a detector. The sensing end is cast molded with a diameter of 3-mm over the last 20-mm, yielding a low profile sensor. This reflective triangulation approach is probably the oldest and simplest fiber proximity sensing approach, yet the novelty here is in demonstrating high sensitivity at low expense from a triangular microstructure with amorphous magnetic coatings of iron, cobalt, permalloy, etc. The signal intensity versus distance curve yields an approximate gaussian shape. For a typical configuration, the signal grows from 10% to 90% of maximum in traversing from 6 to 50 microns from a coated cantilever. With signal levels exceeding a volt, nanometer resolution should be readily achievable for periodic signals.« less

Direct demonstration of persistent Na+ channel activity in dendritic processes of mammalian cortical neurones

PubMed Central

Magistretti, Jacopo; Ragsdale, David S; Alonso, Angel

1999-01-01

Single Na+ channel activity was recorded in patch-clamp, cell-attached experiments performed on dendritic processes of acutely isolated principal neurones from rat entorhinal-cortex layer II. The distances of the recording sites from the soma ranged from ≈20 to ≈100 μm.Step depolarisations from holding potentials of −120 to −100 mV to test potentials of −60 to +10 mV elicited Na+ channel openings in all of the recorded patches (n= 16).In 10 patches, besides transient Na+ channel openings clustered within the first few milliseconds of the depolarising pulses, prolonged and/or late Na+ channel openings were also regularly observed. This ‘persistent’ Na+ channel activity produced net inward, persistent currents in ensemble-average traces, and remained stable over the entire duration of the experiments (≈9 to 30 min).Two of these patches contained <= 3 channels. In these cases, persistent Na+ channel openings could be attributed to the activity of one single channel.The voltage dependence of persistent-current amplitude in ensemble-average traces closely resembled that of whole-cell, persistent Na+ current expressed by the same neurones, and displayed the same characteristic low threshold of activation.Dendritic, persistent Na+ channel openings had relatively high single-channel conductance (≈20 pS), similar to what is observed for somatic, persistent Na+ channels.We conclude that a stable, persistent Na+ channel activity is expressed by proximal dendrites of entorhinal-cortex layer II principal neurones, and can contribute a significant low-threshold, persistent Na+ current to the dendritic processing of excitatory synaptic inputs. PMID:10601494

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.

Na+ current in presynaptic terminals of the crayfish opener cannot initiate action potentials.

PubMed

Lin, Jen-Wei

2016-01-01

Action potential (AP) propagation in presynaptic axons of the crayfish opener neuromuscular junction (NMJ) was investigated by simultaneously recording from a terminal varicosity and a proximal branch. Although orthodromically conducting APs could be recorded in terminals with amplitudes up to 70 mV, depolarizing steps in terminals to -20 mV or higher failed to fire APs. Patch-clamp recordings did detect Na(+) current (INa) in most terminals. The INa exhibited a high threshold and fast activation rate. Local perfusion of Na(+)-free saline showed that terminal INa contributed to AP waveform by slightly accelerating the rising phase and increasing the peak amplitude. These findings suggest that terminal INa functions to "touch up" but not to generate APs. Copyright © 2016 the American Physiological Society.

Clonidine reduces diarrhea and sodium loss in patients with proximal jejunostomy: a controlled study.

PubMed

Buchman, Alan L; Fryer, Jon; Wallin, Anita; Ahn, Chul W; Polensky, Sharon; Zaremba, Karen

2006-01-01

Patients with short bowel syndrome have significant fluid losses. This represents a significant management problem, especially in patients with minimal residual intestine. We determined whether clonidine, an alpha2-adrenergic agonist, is effective in decreasing fecal water and sodium (Na) losses in patients with proximal jejunostomy. Eight parenteral nutrition (PN)-dependent subjects (3 men, 5 women), aged 49.9+/-10.2 years, with a residual small bowel length of 71.8+/-152.0 cm that ended in a jejunostomy, were studied. Subjects were admitted to the North-western General Clinical Research Center (GCRC) for a 2-day equilibrium period while receiving a self-selected 100 g fat diet with protein 1.5 g/kg/d and 30 kcal/kg/d and 1 L/d of oral rehydration solution. A D-xylose test was performed after an overnight fast. On days 3-5, all stool and urine were collected for volume, weight, fat, nitrogen, energy, sodium, magnesium, potassium, and calcium. Meals were provided in duplicate and the equivalent portions consumed by each patient were analyzed for fluid volume, fat, nitrogen, energy, sodium, magnesium, calcium, and potassium in order to calculate nutrient balances. At the conclusion of the stool and urine collections (day 6), a clonidine (0.3 mg) patch was applied to the shoulder. Subjects were restudied after 1 week. Daily fecal volume and weight were 4.514+/-1.769 L/d and 4394+/-1727 g/d, respectively, at baseline. Five subjects were net "secretors" in that excreted fecal volume exceeded oral intake. Fecal volume decreased by 427+/-562 mL/d (8.9%, p=.07). Fecal weight decreased by 438+/-527 g/d (9.4%, p=.05). Urine volume correspondingly increased by 747+/-1934 mL (18.9%, p=not significant [NS]). The increase in urine output was weakly and negatively correlated with the decrease in fecal volume and weight (r=-0.37 and -0.41, respectively, p=NS). Oral fluid intake decreased slightly from 3.328+/-1.246 L/d baseline to 3.203+/-1.119 L/d with clonidine therapy (-3

Embedded System Implementation of Sound Localization in Proximal Region

NASA Astrophysics Data System (ADS)

Iwanaga, Nobuyuki; Matsumura, Tomoya; Yoshida, Akihiro; Kobayashi, Wataru; Onoye, Takao

A sound localization method in the proximal region is proposed, which is based on a low-cost 3D sound localization algorithm with the use of head-related transfer functions (HRTFs). The auditory parallax model is applied to the current algorithm so that more accurate HRTFs can be used for sound localization in the proximal region. In addition, head-shadowing effects based on rigid-sphere model are reproduced in the proximal region by means of a second-order IIR filter. A subjective listening test demonstrates the effectiveness of the proposed method. Embedded system implementation of the proposed method is also described claiming that the proposed method improves sound effects in the proximal region only with 5.1% increase of memory capacity and 8.3% of computational costs.

Risk factors associated with the occurrence of proximal humerus fractures in patients with rheumatoid arthritis: a custom strategy for preventing proximal humerus fractures.

PubMed

Ochi, Kensuke; Furuya, Takefumi; Ishibashi, Mina; Watanabe, Makiko; Ikari, Katsunori; Taniguchi, Atsuo; Yamanaka, Hisashi; Momohara, Shigeki

2016-02-01

To our knowledge, no prior report focused on the risk factors for proximal humerus fractures in patients with rheumatoid arthritis. The purpose of this study was to evaluate the association between potential risk factors and the occurrence of proximal humerus fractures in patients with rheumatoid arthritis. A total of 11,907 patients with rheumatoid arthritis were enrolled in our observational cohort rheumatoid arthritis study between 2000 and 2012. Self-reported proximal humerus fractures were verified using the patients' medical records. Cox proportional hazard models were used to analyze the independent contribution of risk factors to the occurrence of proximal humerus fractures. During follow-up (mean 5.6 years), 92 proximal humerus fractures were verified in 91 patients. Multivariate Cox regression analyses estimated that the hazard ratios of sustaining a proximal humerus fracture were 1.37 for every 10-year increase in age [95 % confidence interval (CI) 1.10-1.70; P < 0.01], 1.95 for increases in serum C-reactive protein levels (mg/100 mL; 95 % CI 1.15-3.34; P < 0.05), 2.13 for a history of fractures (95 % CI 1.34-3.40; P < 0.01), 1.07 for the daily prednisolone dose (per mg; 95 % CI 1.01-1.13; P < 0.05), and 1.97 for oral bisphosphonate use (95 % CI 1.20-3.23; P < 0.01). Better control of rheumatoid arthritis with a smaller daily prednisolone dose in elderly patients with a history of fractures may be important for preventing proximal humerus fractures.

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…

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.

Electromagnetic properties of proximity systems

NASA Astrophysics Data System (ADS)

Kresin, Vladimir Z.

1985-07-01

Magnetic screening in the proximity system Sα-Mβ, where Mβ is a normal metal N, semiconductor (semimetal), or a superconductor, is studied. Main attention is paid to the low-temperature region where nonlocality plays an important role. The thermodynamic Green's-function method is employed in order to describe the behavior of the proximity system in an external field. The temperature and thickness dependences of the penetration depth λ are obtained. The dependence λ(T) differs in a striking way from the dependence in usual superconductors. The strong-coupling effect is taken into account. A special case of screening in a superconducting film backed by a size-quantizing semimetal film is considered. The results obtained are in good agreement with experimental data.

Analysis of proximal and distal muscle activity during handwriting tasks.

PubMed

Naider-Steinhart, Shoshana; Katz-Leurer, Michal

2007-01-01

In this study we sought to describe upper-extremity proximal and distal muscle activity in typically developing children during a handwriting task and to explore the relationship between muscle activity and speed and quality of writing. We evaluated 35 third- and fourth-grade Israeli children using the Alef-Alef Ktav Yad Hebrew Handwriting Test. Simultaneously, we recorded the participants' upper trapezius and thumb muscle activity by surface electromyography. Using the coefficient of variation (standard deviation divided by mean amplitude) as a measure of variability within each muscle, we analyzed differences in muscle activity variability within and between muscles. The proximal muscle displayed significantly less variability than the distal muscles. Decreased variability in proximal muscle activity was associated with decreased variability in distal muscle activity, and decreased variability in the distal muscles was significantly associated with faster speed of writing. The lower amount of variability exhibited in the proximal muscle compared with the distal muscles seems to indicate that the proximal muscle functions as a stabilizer during a handwriting task. In addition, decreased variability in both proximal and distal muscle activity appears to be more economical and is related to faster writing speed. Knowledge of the type of proximal and distal muscle activity used during handwriting can help occupational therapists plan treatment for children with handwriting disabilities.

Proximity operations concept design study, task 6

NASA Technical Reports Server (NTRS)

Williams, A. N.

1990-01-01

The feasibility of using optical technology to perform the mission of the proximity operations communications subsystem on Space Station Freedom was determined. Proximity operations mission requirements are determined and the relationship to the overall operational environment of the space station is defined. From this information, the design requirements of the communication subsystem are derived. Based on these requirements, a preliminary design is developed and the feasibility of implementation determined. To support the Orbital Maneuvering Vehicle and National Space Transportation System, the optical system development is straightforward. The requirements on extra-vehicular activity are such as to allow large fields of uncertainty, thus exacerbating the acquisition problem; however, an approach is given that could mitigate this problem. In general, it is found that such a system could indeed perform the proximity operations mission requirement, with some development required to support extra-vehicular activity.

Renal proximal tubule function is preserved in Cftrtm2camΔF508 cystic fibrosis mice

PubMed Central

Kibble, J D; Balloch, K J D; Neal, A M; Hill, C; White, S; Robson, L; Green, R; Taylor, C J

2001-01-01

Changes in proximal tubule function have been reported in cystic fibrosis patients. The aim of this study was to investigate proximal tubule function in the Cftrtm2camΔF508 cystic fibrosis (CF) mouse model. A range of techniques were used including renal clearance studies, in situ microperfusion, RT-PCR and whole-cell patch clamping. Renal Na+ clearance was similar in wild-type (1.4 ± 0.3 μl min−1, number of animals, N= 12) and CF mice (1.6 ± 0.4 μl min−1, N= 7) under control conditions. Acute extracellular volume expansion resulted in significant natriuresis in wild-type (7.0 ± 0.8 μl min−1, N= 8) and CF mice (9.3 ± 1.4 μl min−1, N= 9); no difference between genotypes was observed. In situ microperfusion revealed that fluid absorptive rate (Jv) was similar under control conditions between wild-type (2.2 ± 0.4 nl mm−1 min−1, n= 10) and CF mice (1.9 ± 0.3 nl mm−1 min−1, n= 11). Addition of a forskolin-dibutyryl cAMP (db-cAMP) cocktail to the perfusate caused no significant change in Jv in either wild-type (2.6 ± 0.7 nl mm−1 min−1, n= 10) or Cftrtm2camΔF508 mice (2.0 ± 0.5 nl mm−1 min−1, n= 10). CFTR expression was confirmed in samples of outer cortex using RT-PCR. However, no evidence for functional CFTR was obtained when outer cortical cells were stimulated with protein kinase A or forskolin-db-cAMP using whole-cell patch clamping. In conclusion, no functional deficit in proximal tubule function was found in Cftrtm2camΔF508 mice. This may be a consequence of a lack of whole-cell cAMP-dependent Cl− conductance in mouse proximal tubule cells. PMID:11306663

Superconducting proximity effect in topological materials

NASA Astrophysics Data System (ADS)

Reeg, Christopher R.

In recent years, there has been a renewed interest in the proximity effect due to its role in the realization of topological superconductivity. In this dissertation, we discuss several results that have been obtained in the field of proximity-induced superconductivity and relate the results to the search for Majorana fermions. First, we show that repulsive electron-electron interactions can induce a non-Majorana zero-energy bound state at the interface between a conventional superconductor and a normal metal. We show that this state is very sensitive to disorder, owing to its lack of topological protection. Second, we show that Rashba spin-orbit coupling, which is one of the key ingredients in engineering a topological superconductor, induces triplet pairing in the proximity effect. When the spin-orbit coupling is strong (i.e., when the characteristic energy scale for spin-orbit coupling is comparable to the Fermi energy), the induced singlet and triplet pairing amplitudes can be comparable in magnitude. Finally, we discuss how the size of the proximity-induced gap, which appears in a low-dimensional material coupled to a superconductor, evolves as the thickness of the (quasi-)low-dimensional material is increased. We show that the induced gap can be comparable to the bulk energy gap of the underlying superconductor in materials that are much thicker than the Fermi wavelength, even in the presence of an interfacial barrier and strong Fermi surface mismatch. This result has important experimental consequences for topological superconductivity, as a sizable gap is required to isolate and detect the Majorana modes.

Proximal gastrectomy versus total gastrectomy for proximal gastric carcinoma. A meta-analysis on postoperative complications, 5-year survival, and recurrence rate.

PubMed

Pu, Yu-Wei; Gong, Wei; Wu, Yong-You; Chen, Qiang; He, Teng-Fei; Xing, Chun-Gen

2013-12-01

To compare proximal gastrectomy (PG) with total gastrectomy (TG) for proximal gastric carcinoma, through the 5-year survival rate, recurrence rate, postoperative complications, and long-term life quality. The meta-analysis was carried out in the General Surgery Department of the Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China. We searched Medline, EMBASE, and the Cochrane Library from June to November 2012. The literature searches were carried out using medical subject headings and free-text word: `proximal gastrectomy` `total gastrectomy` `partial gastrectomy` `stomach neoplasms` and `gastric cancer`. Two different reviewers carried out the search and evaluated studies independently. Two randomized controlled trials and 9 retrospective studies were included. A total of 1364 patients were included in our study. Our analysis showed that there is no statistically significant difference in 5-year survival rate between PG and TG (60.9% versus 64.4%). But, the recurrence is higher in the PG group than the TG (38.7% versus 24.4%). The anastomotic stenosis rate is also higher in the PG than the TG (27.4% versus 7.4%). Proximal gastrectomy is an option for upper third gastric cancer in terms of safety. However, it is associated with high risk of reflux symptoms and anastomotic stenosis. Therefore, TG should be the first choice for proximal gastric cancer to prevent reflux symptoms.

Pediatric distal femur fixation by proximal humeral plate.

PubMed

Abdelgawad, Amr Atef; Kanlic, Enes M

2013-12-01

Distal femoral metaphyseal fractures are common injuries in children. Multiple treatment options have been described for this type of injury. For older children with distal metaphyseal fracture, there is still no optimal method of fixation. We propose that the commonly used proximal humeral plate can provide good method of fixation for this fracture in adolescents. Two children (12 and 14 years old) with distal metaphyseal femoral fracture were treated with proximal humeral plate. We describe the surgical technique and postoperative management. The two children healed with good alignment and full range of motion of the knee. No external immobilization (other than knee immobilizer for the first 2 weeks) was used. We concluded that proximal humeral plate can provide adequate fixation for teenagers with distal femoral metaphyseal fracture. It is readily available; provide multiple options for screw fixation in the distal part of the fracture and fits easily on the distal part of the femur proximal to the physis. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Anatomy and Biomechanics of the Finger Proximal Interphalangeal Joint.

PubMed

Pang, Eric Quan; Yao, Jeffrey

2018-05-01

A complete understanding of the normal anatomy and biomechanics of the proximal interphalangeal joint is critical when treating pathology of the joint as well as in the design of new reconstructive treatments. The osseous anatomy dictates the principles of motion at the proximal interphalangeal joint. Subsequently, the joint is stabilized throughout its motion by the surrounding proximal collateral ligament, accessory collateral ligament, and volar plate. The goal of this article is to review the normal anatomy and biomechanics of the proximal interphalangeal joint and its associated structures, most importantly the proper collateral ligament, accessory collateral ligament, and volar plate. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

Fluoroscopically Guided Peritendinous Corticosteroid Injection for Proximal Hamstring Tendinopathy

PubMed Central

Nicholson, Luke T.; DiSegna, Steven; Newman, Joel S.; Miller, Suzanne L.

2014-01-01

Background: Proximal hamstring tendinopathy is an uncommon but debilitating cause of posterior thigh pain in athletes subjected to repetitive eccentric hamstring contraction, such as runners. Minimal data exist evaluating treatment options for proximal hamstring tendinopathy. Purpose: This retrospective study evaluates the effectiveness of fluoroscopically guided corticosteroid injections in treating proximal hamstring tendinopathy. Study Design: Case series; Level of evidence, 4. Methods: Eighteen athletes with 22 cases of magnetic resonance imaging–confirmed proximal hamstring tendinopathy were treated with corticosteroid injection and later contacted to evaluate the efficacy of the injection with the use of a questionnaire. Results: The visual analog score decreased from 7.22 preinjection to 3.94 postinjection (P < .001), level of athletic participation increased from 28.76% to 68.82% (P < .001) at a mean follow-up of 21 months, and 38.8% of patients experienced complete resolution at a mean follow-up of 24.8 months. The mean lower extremity function score at the time of follow-up was 60. Conclusion: A trial of fluoroscopically guided corticosteroid injection is warranted in patients presenting with symptoms of proximal hamstring tendinopathy refractory to conservative therapy. PMID:26535310

Muscular innervation of the proximal duodenum of the guinea pig.

PubMed

Iino, S

2000-10-01

We investigated the muscular structure and innervation of the gastroduodenal junction in the guinea pig. In the gastroduodenal junction, the innermost layer of the circular muscle contained numerous nerve fibers and terminals. Since this nerve network continued onto the deep muscular plexus (DMP) of the duodenum, we surmised that the numerous nerve fibers in the gastroduodenal junction were specialized DMP in the most proximal part of the duodenum. The innermost layer containing many nerve fibers was about 1,000 microm in length and 100 microm in thickness in the proximal duodenum. This layer contained numerous connective tissue fibers composed of collagen and elastic fibers. Five to 30 smooth muscle cells lay in contact with each other and were surrounded by fine connective tissue. The nerve fibers in the proximal duodenum contained nerve terminals immunoreactive for choline acetyltransferase, dynorphin, enkephalin, galanin, gastrin-releasing peptide, nitric oxide synthase, substance P, and vasoactive intestinal polypeptide. Adrenergic fibers which contained tyrosine hydroxylase immunoreactivity were rare in the proximal duodenum. In the innermost layer of the proximal duodenum, there were numerous c-Kit immunopositive cells that were in contact with nerve terminals. This study allowed us to clarify the specific architecture of the most proximal portion of the duodenum. The functional significance of the proximal duodenum in relation to the electrical connection and neural cooperation of the musculature between the antrum and the duodenum is also discussed.

Object detection system using SPAD proximity detectors

NASA Astrophysics Data System (ADS)

Stark, Laurence; Raynor, Jeffrey M.; Henderson, Robert K.

2011-10-01

This paper presents an object detection system based upon the use of multiple single photon avalanche diode (SPAD) proximity sensors operating upon the time-of-flight (ToF) principle, whereby the co-ordinates of a target object in a coordinate system relative to the assembly are calculated. The system is similar to a touch screen system in form and operation except that the lack of requirement of a physical sensing surface provides a novel advantage over most existing touch screen technologies. The sensors are controlled by FPGA-based firmware and each proximity sensor in the system measures the range from the sensor to the target object. A software algorithm is implemented to calculate the x-y coordinates of the target object based on the distance measurements from at least two separate sensors and the known relative positions of these sensors. Existing proximity sensors were capable of determining the distance to an object with centimetric accuracy and were modified to obtain a wide field of view in the x-y axes with low beam angle in z in order to provide a detection area as large as possible. Design and implementation of the firmware, electronic hardware, mechanics and optics are covered in the paper. Possible future work would include characterisation with alternative designs of proximity sensors, as this is the component which determines the highest achievable accur1acy of the system.

Proximal Junctional Kyphosis Following Spinal Deformity Surgery in the Pediatric Patient.

PubMed

Cho, Samuel K; Kim, Yongjung J; Lenke, Lawrence G

2015-07-01

Proper understanding and restoration of sagittal balance is critical in spinal deformity surgery, including conditions such as adolescent idiopathic scoliosis and Scheuermann kyphosis. One potential complication following spinal reconstruction is proximal junctional kyphosis. The prevalence of proximal junctional kyphosis varies in the literature, and several patient- and surgery-related risk factors have been identified. To date, the development of proximal junctional kyphosis has not been shown to lead to a negative clinical outcome following spinal fusion for adolescent idiopathic scoliosis or Scheuermann kyphosis. Treatment options range from simple observation in asymptomatic cases to revision surgery with extension of the fusion proximally. Several techniques and technologies are emerging that seek to address and prevent proximal junctional kyphosis. Copyright 2015 by the American Academy of Orthopaedic Surgeons.

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,…

The sooner, the better: exercise outcome proximity and intrinsic motivation.

PubMed

Evans, M Blair; Cooke, Lisa M; Murray, Robyn A; Wilson, Anne E

2014-11-01

Despite evidence that outcomes are highly valued when they are expected sooner rather than further into the future (Ainslie, 1975), limited research effort has been devoted to understanding the role of exercise outcome proximity. The purpose of this study was to examine how temporal proximity to positive outcomes influences exercisers' intrinsic motivation. We expected that focusing people on temporally proximal exercise outcomes would increase intrinsic motivation, especially among low-frequency exercisers. This online experimental study was completed by 135 community exercisers (Mage  = 31.11, SD = 10.29; 62% female) who reported an average of 4.86 exercise bouts per week (SD = 2.12). Participants were randomly assigned to a condition that primed temporally proximal positive exercise outcomes (i.e. experienced during or directly following an exercise bout) or temporally distal outcomes (i.e. experienced after days, months, or years of regular exercise). Participants then reported perceptions of behavioral regulation in exercise. As expected, the proximal exercise outcome condition elicited increased intrinsic regulation among those participants who exercised less frequently (i.e. 1 SD below the mean). This study reveals the importance of considering proximity as an important dimension of exercise outcomes-particularly when promoting intrinsic motivation among relatively infrequent exercisers. © 2014 The International Association of Applied Psychology.

The Lateral Proximal Phalanx Flap for Contractures and Soft Tissue Defects in the Proximal Interphalangeal Joint

PubMed Central

Beltrán, Aldo G.; Romero, Camilo J.

2016-01-01

Background: The management of contractures and soft tissue defects in the proximal interphalangeal (PIP) finger joint remains a challenge. We report a transposition flap from the lateral skin of the proximal phalanx that is based on perforating branches of the digital arteries and can be used safely for both palmar and dorsal cover defects. Methods: We first completed an anatomic study, dissecting 20 fingers in fresh cadavers with arterial injections and made the new flap in patients with dorsal or palmar defects in PIP joints. Results: In cadavers, we can reveal 4 constant branches from each digital artery in the proximal phalanx, with the more distal just in the PIP joint constituting the flap pedicle. Between February 2010 and February 2015, we designed 33 flaps in 29 patients, 7 for dorsal and 26 for palmar defects, with no instances of flap necrosis and 4 distal epidermolysis. The patients were between 4 and 69 years with no major complications, and all of the skin defects in the PIP joint were resolved satisfactorily without any relevant sequelae at the donor site. Conclusions: This flap procedure is an easy, reliable, versatile, and safe technique, and could be an important tool for the management of difficult skin defects and contractures at the PIP joint level. PMID:28082850

Infrared-Proximity-Sensor Modules For Robot

NASA Technical Reports Server (NTRS)

Parton, William; Wegerif, Daniel; Rosinski, Douglas

1995-01-01

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

Tools for proximal soil sensing

USDA-ARS?s Scientific Manuscript database

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...

[Disorders of sex development and proximal hypospadias].

PubMed

Oswald, J

2016-01-01

Children with ambiguous genitalia due to different chromosome or gonadal sex are a particular challenge concerning the diagnostic and therapeutic implications. Proximal hypospadias patients with normal gonadal development should be distinguished from children with DSD (disorders of sex development) to guarantee normal gender identity and the best possible surgical therapy. This paper focuses on the terminology, embryology, and pathophysiology of the different manifestations of DSD. The state of knowledge about this disease pattern with particular emphasis on proximal hypospadias based on national and international scientific discussions is presented. The different clinical pictures as well as therapeutic options of DSD with a special focus on recent literature and giving particular attention to patients with proximal hypospadias are presented. Because of the complexity of patients suffering from disorders of sex development an interdisciplinary DSD healthcare team including a paediatric endocrinologist as well as paediatric urologist should be provided. These specialists enable an accurate diagnosis in severe hypospadias patients without reference to DSD diseases patterns.

Correlation between social proximity and mobility similarity.

PubMed

Fan, Chao; Liu, Yiding; Huang, Junming; Rong, Zhihai; Zhou, Tao

2017-09-20

Human behaviors exhibit ubiquitous correlations in many aspects, such as individual and collective levels, temporal and spatial dimensions, content, social and geographical layers. With rich Internet data of online behaviors becoming available, it attracts academic interests to explore human mobility similarity from the perspective of social network proximity. Existent analysis shows a strong correlation between online social proximity and offline mobility similarity, namely, mobile records between friends are significantly more similar than between strangers, and those between friends with common neighbors are even more similar. We argue the importance of the number and diversity of common friends, with a counter intuitive finding that the number of common friends has no positive impact on mobility similarity while the diversity plays a key role, disagreeing with previous studies. Our analysis provides a novel view for better understanding the coupling between human online and offline behaviors, and will help model and predict human behaviors based on social proximity.

Proximal caries detection: Sirona Sidexis versus Kodak Ektaspeed Plus.

PubMed

Khan, Emad A; Tyndall, Donald A; Ludlow, John B; Caplan, Daniel

2005-01-01

This study compared the accuracy of intraoral film and a charge-coupled device (CCD) receptor for proximal caries detection. Four observers evaluated images of the proximal surfaces of 40 extracted posterior teeth. The presence or absence of caries was scored using a five-point confidence scale. The actual status of each surface was determined from ground section histology. Responses were evaluated by means of receiver operating characteristic (ROC) analysis. Areas under ROC curves (Az) were assessed through a paired t-test. The performance of the CCD-based intraoral sensor was not different statistically from Ektaspeed Plus film in detecting proximal caries.

Cyclophilin B Interacts with Sodium-Potassium ATPase and Is Required for Pump Activity in Proximal Tubule Cells of the Kidney

PubMed Central

Suñé, Guillermo; Sarró, Eduard; Puigmulé, Marta; López-Hellín, Joan; Zufferey, Madeleine; Pertel, Thomas; Luban, Jeremy; Meseguer, Anna

2010-01-01

Cyclophilins (Cyps), the intracellular receptors for Cyclosporine A (CsA), are responsible for peptidyl-prolyl cis-trans isomerisation and for chaperoning several membrane proteins. Those functions are inhibited upon CsA binding. Albeit its great benefits as immunosuppressant, the use of CsA has been limited by undesirable nephrotoxic effects, including sodium retention, hypertension, hyperkalemia, interstial fibrosis and progressive renal failure in transplant recipients. In this report, we focused on the identification of novel CypB-interacting proteins to understand the role of CypB in kidney function and, in turn, to gain further insight into the molecular mechanisms of CsA-induced toxicity. By means of yeast two-hybrid screens with human kidney cDNA, we discovered a novel interaction between CypB and the membrane Na/K-ATPase β1 subunit protein (Na/K-β1) that was confirmed by pull-down, co-immunoprecipitation and confocal microscopy, in proximal tubule-derived HK-2 cells. The Na/K-ATPase pump, a key plasma membrane transporter, is responsible for maintenance of electrical Na+ and K+ gradients across the membrane. We showed that CypB silencing produced similar effects on Na/K-ATPase activity than CsA treatment in HK-2 cells. It was also observed an enrichment of both alpha and beta subunits in the ER, what suggested a possible failure on the maturation and routing of the pump from this compartment towards the plasma membrane. These data indicate that CypB through its interaction with Na/K-β1 might regulate maturation and trafficking of the pump through the secretory pathway, offering new insights into the relationship between cyclophilins and the nephrotoxic effects of CsA. PMID:21085665

Cyclophilin B interacts with sodium-potassium ATPase and is required for pump activity in proximal tubule cells of the kidney.

PubMed

Suñé, Guillermo; Sarró, Eduard; Puigmulé, Marta; López-Hellín, Joan; Zufferey, Madeleine; Pertel, Thomas; Luban, Jeremy; Meseguer, Anna

2010-11-10

Cyclophilins (Cyps), the intracellular receptors for Cyclosporine A (CsA), are responsible for peptidyl-prolyl cis-trans isomerisation and for chaperoning several membrane proteins. Those functions are inhibited upon CsA binding. Albeit its great benefits as immunosuppressant, the use of CsA has been limited by undesirable nephrotoxic effects, including sodium retention, hypertension, hyperkalemia, interstial fibrosis and progressive renal failure in transplant recipients. In this report, we focused on the identification of novel CypB-interacting proteins to understand the role of CypB in kidney function and, in turn, to gain further insight into the molecular mechanisms of CsA-induced toxicity. By means of yeast two-hybrid screens with human kidney cDNA, we discovered a novel interaction between CypB and the membrane Na/K-ATPase β1 subunit protein (Na/K-β1) that was confirmed by pull-down, co-immunoprecipitation and confocal microscopy, in proximal tubule-derived HK-2 cells. The Na/K-ATPase pump, a key plasma membrane transporter, is responsible for maintenance of electrical Na+ and K+ gradients across the membrane. We showed that CypB silencing produced similar effects on Na/K-ATPase activity than CsA treatment in HK-2 cells. It was also observed an enrichment of both alpha and beta subunits in the ER, what suggested a possible failure on the maturation and routing of the pump from this compartment towards the plasma membrane. These data indicate that CypB through its interaction with Na/K-β1 might regulate maturation and trafficking of the pump through the secretory pathway, offering new insights into the relationship between cyclophilins and the nephrotoxic effects of CsA.

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

Close Association of Carbonic Anhydrase (CA2a and CA15a), Na+/H+ Exchanger (Nhe3b), and Ammonia Transporter Rhcg1 in Zebrafish Ionocytes Responsible for Na+ Uptake

PubMed Central

Ito, Yusuke; Kobayashi, Sayako; Nakamura, Nobuhiro; Miyagi, Hisako; Esaki, Masahiro; Hoshijima, Kazuyuki; Hirose, Shigehisa

2013-01-01

Freshwater (FW) fishes actively absorb salt from their environment to tolerate low salinities. We previously reported that vacuolar-type H+-ATPase/mitochondrion-rich cells (H-MRCs) on the skin epithelium of zebrafish larvae (Danio rerio) are primary sites for Na+ uptake. In this study, in an attempt to clarify the mechanism for the Na+ uptake, we performed a systematic analysis of gene expression patterns of zebrafish carbonic anhydrase (CA) isoforms and found that, of 12 CA isoforms, CA2a and CA15a are highly expressed in H-MRCs at larval stages. The ca2a and ca15a mRNA expression were salinity-dependent; they were upregulated in 0.03 mM Na+ water whereas ca15a but not ca2a was down-regulated in 70 mM Na+ water. Immunohistochemistry demonstrated cytoplasmic distribution of CA2a and apical membrane localization of CA15a. Furthermore, cell surface immunofluorescence staining revealed external surface localization of CA15a. Depletion of either CA2a or CA15a expression by Morpholino antisense oligonucleotides resulted in a significant decrease in Na+ accumulation in H-MRCs. An in situ proximity ligation assay demonstrated a very close association of CA2a, CA15a, Na+/H+ exchanger 3b (Nhe3b), and Rhcg1 ammonia transporter in H-MRC. Our findings suggest that CA2a, CA15a, and Rhcg1 play a key role in Na+uptake under FW conditions by forming a transport metabolon with Nhe3b. PMID:23565095

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.

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

Experimental Evaluation Methodology for Spacecraft Proximity Maneuvers in a Dynamic Environment

DTIC Science & Technology

2017-06-01

NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA DISSERTATION EXPERIMENTAL EVALUATION METHODOLOGY FOR SPACECRAFT PROXIMITY MANEUVERS IN A DYNAMIC...29, 2014 – June 16, 2017 4. TITLE AND SUBTITLE EXPERIMENTAL EVALUATION METHODOLOGY FOR SPACECRAFT PROXIMITY MANEUVERS IN A DYNAMIC ENVIRONMENT 5...LEFT BLANK ii Approved for public release. Distribution is unlimited. EXPERIMENTAL EVALUATION METHODOLOGY FOR SPACECRAFT PROXIMITY MANEUVERS IN A

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

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.

Proximal location of mouse prostate epithelial stem cells

PubMed Central

Tsujimura, Akira; Koikawa, Yasuhiro; Salm, Sarah; Takao, Tetsuya; Coetzee, Sandra; Moscatelli, David; Shapiro, Ellen; Lepor, Herbert; Sun, Tung-Tien; Wilson, E. Lynette

2002-01-01

Stem cells are believed to regulate normal prostatic homeostasis and to play a role in the etiology of prostate cancer and benign prostatic hyperplasia. We show here that the proximal region of mouse prostatic ducts is enriched in a subpopulation of epithelial cells that exhibit three important attributes of epithelial stem cells: they are slow cycling, possess a high in vitro proliferative potential, and can reconstitute highly branched glandular ductal structures in collagen gels. We propose a model of prostatic homeostasis in which mouse prostatic epithelial stem cells are concentrated in the proximal region of prostatic ducts while the transit-amplifying cells occupy the distal region of the ducts. This model can account for many biological differences between cells of the proximal and distal regions, and has implications for prostatic disease formation. PMID:12082083

Protein biomarker validation via proximity ligation assays.

PubMed

Blokzijl, A; Nong, R; Darmanis, S; Hertz, E; Landegren, U; Kamali-Moghaddam, M

2014-05-01

The ability to detect minute amounts of specific proteins or protein modifications in blood as biomarkers for a plethora of human pathological conditions holds great promise for future medicine. Despite a large number of plausible candidate protein biomarkers published annually, the translation to clinical use is impeded by factors such as the required size of the initial studies, and limitations of the technologies used. The proximity ligation assay (PLA) is a versatile molecular tool that has the potential to address some obstacles, both in validation of biomarkers previously discovered using other techniques, and for future routine clinical diagnostic needs. The enhanced specificity of PLA extends the opportunities for large-scale, high-performance analyses of proteins. Besides advantages in the form of minimal sample consumption and an extended dynamic range, the PLA technique allows flexible assay reconfiguration. The technology can be adapted for detecting protein complexes, proximity between proteins in extracellular vesicles or in circulating tumor cells, and to address multiple post-translational modifications in the same protein molecule. We discuss herein requirements for biomarker validation, and how PLA may play an increasing role in this regard. We describe some recent developments of the technology, including proximity extension assays, the use of recombinant affinity reagents suitable for use in proximity assays, and the potential for single cell proteomics. This article is part of a Special Issue entitled: Biomarkers: A Proteomic Challenge. © 2013.

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

Proximal-type epithelioid sarcoma - Case report*

PubMed Central

dos Santos, Luciana Mendes; Nogueira, Lisiane; Matsuo, Christiane Yuri; Talhari, Carolina; Santos, Mônica

2013-01-01

Epithelioid sarcoma, first described by Enzinger in 1970, is a rare soft-tissue sarcoma typically presenting as a subcutaneous or deep dermal mass in distal portions of the extremities of adolescents and young adults. In 1997, Guillou et al. described a different type of epithelioid sarcoma, called proximal-type epithelioid sarcoma, which is found mostly in the pelvic and perineal regions and genital tracts of young to middle-aged adults. It is characterized by a proliferation of epithelioid-like cells with rhabdoid features and the absence of a granuloma-like pattern. In this paper we present a case of proximal-type epithelioid sarcoma with an aggressive clinical course, including distant metastasis and death nine months after diagnosis. PMID:23793215

Inter-proximal enamel reduction in contemporary orthodontics.

PubMed

Pindoria, J; Fleming, P S; Sharma, P K

2016-12-16

Inter-proximal enamel reduction has gained increasing prominence in recent years being advocated to provide space for orthodontic alignment, to refine contact points and to potentially improve long-term stability. An array of techniques and products are available ranging from hand-held abrasive strips to handpiece mounted burs and discs. The indications for inter-proximal enamel reduction and the importance of formal space analysis, together with the various techniques and armamentarium which may be used to perform it safely in both the labial and buccal segments are outlined.

Ionic requirements of proximal tubular sodium transport. I. Bicarbonate and chloride.

PubMed

Green, R; Giebisch, G

1975-11-01

Simultaneous perfusion of peritubular capillaries and proximal convoluted tubules was used to study the effect of varying transepithelial ionic gradients on ionic fluxes. Results show that net sodium influx and volume flux was one-third of normal when bicarbonate was absent, no chloride gradient existed, and glucose and amino acids were absent. Addition of bicarbonate to the luminal fluid did not restore the flux to normal, but peritubular bicarbonate did restore it. A chloride gradient imposed when no bicarbonate was present could only increase the fluxes slightly, but his flux was significant even after cyanide had poisoned transport. Reversing the chloride concentration gradient decreased the net sodium and volume fluxes whether bicarbonate was present or not. Glucose had no effect on fluxes, but substitution of Na by choline abolished them entirely. It is concluded that sodium is actively transported, that a chloride concentration gradient from lumen to plasma could account for up to 20% of net transport, and that peritubular bicarbonate is necessary for normal rates of sodium and fluid absorption.

Proximal femoral bone loss and increased rate of fracture with a proximally hydroxyapatite-coated femoral component.

PubMed

Radl, R; Aigner, C; Hungerford, M; Pascher, A; Windhager, R

2000-11-01

We performed a retrospective analysis of the clinical and radiological outcomes of total hip replacement using an uncemented femoral component proximally coated with hydroxyapatite. Of 136 patients, 118 who had undergone 124 primary total hip replacements were available for study. Their mean age was 66.5 years (19 to 90) and the mean follow-up was 5.6 years (4.25 to 7.25). At the final follow-up the mean Harris hip score was 92 (47.7 to 100). Periprosthetic femoral fractures, which occurred in seven patients (5.6%), were treated by osteosynthesis in six and conservatively in one. We had to revise five femoral components, one because of aseptic loosening, one because of septic loosening and three because of periprosthetic fracture. At the final follow-up there were definite signs of aseptic loosening in two patients. Radiologically, proximal femoral bone loss in Gruen zones I and VI was evident in 96.8% of hips, while bone hypertrophy in zones III and V was seen in 64.7%. In 24 hips (20.2%) the mean subsidence of the stem was 3.7 mm which occurred within the first 12 postoperative weeks. This indicated poor initial stability, which might have been aggravated by early weight-bearing. The high rate of failure in our study suggests that proximal femoral bone loss affects the long-term survival of the replacement.

Mapping subsurface in proximity to newly-developed sinkhole along roadway.

DOT National Transportation Integrated Search

2013-02-01

MS&T acquired electrical resistivity tomography profiles in immediate proximity to a newly-developed sinkhole in Nixa Missouri : The sinkhole has closed a well-traveled municipal roadway and threatens proximal infrastructure. The intent of this inves...

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.

Na(+)-D-glucose cotransporter in the kidney of Squalus acanthias: molecular identification and intrarenal distribution.

PubMed

Althoff, Thorsten; Hentschel, Hartmut; Luig, Jutta; Schütz, Hendrike; Kasch, Myriam; Kinne, Rolf K-H

2006-04-01

Using primers against conserved regions of mammalian Na(+)-d-glucose cotransporters (SGLT), a cDNA was cloned from the kidney of spiny dogfish shark (Squalus acanthias). On the basis of comparison of amino acid sequence, membrane topology, and putative glycosylation and phosphorylation sites, the cDNA could be shown to belong to the family of sglt genes. Indeed, Na(+)-dependent d-glucose uptake could be demonstrated after expression of the gene in Xenopus laevis oocytes. In a dendrogram, the SGLT from shark kidney has a high homology to the mammalian SGLT2. Computer analysis revealed that the elasmobranch protein is most similar to the mammalian proteins in the transmembrane regions and contains already all the amino acids identified to be functionally important, suggesting early conservation during evolution. Extramembraneous loops show larger variations. This holds especially for loop 13, which has been implied as a phlorizin-binding domain. Antibodies were generated and the intrarenal distribution of the SGLT was studied in cryosections. In parallel, the nephron segments were identified by lectins. Positive immunoreactions were found in the proximal tubule in the early parts PIa and PIb and the late segment PIIb. The large PIIa segment of the proximal tubule showed no reaction. In contrast to the mammalian kidney also the late distal tubule, the collecting tubule, and the collecting duct showed immunoreactivity. The molecular information confirms previous vesicle studies in which a low affinity SGLT with a low stoichiometry has been observed and supports the notion of a similarity of the shark kidney SGLT to the mammalian SGLT2. Despite its presence in the late parts of the nephron, the absence of SGLT in the major part of the proximal tubule, the relatively low affinity, and in particular the low stoichiometry might explain the lack of a T(m) for d-glucose in the shark kidney.

Spool-shaped proximal pedal phalanges.

PubMed

Sutro, C J; Sutro, W H

1986-01-01

We have observed that "spool-shaped" proximal pedal phalanges sometimes are found in single or multiple toes, often affecting both feet. These changes may be present in normal as well as abnormal feet. The etiology is unknown. Such changes do not occur in the hands.

MAP17 Is a Necessary Activator of Renal Na+/Glucose Cotransporter SGLT2

PubMed Central

Coady, Michael J.; El Tarazi, Abdulah; Santer, René; Bissonnette, Pierre; Sasseville, Louis J.; Calado, Joaquim; Lussier, Yoann; Dumayne, Christopher; Bichet, Daniel G.

2017-01-01

The renal proximal tubule reabsorbs 90% of the filtered glucose load through the Na+-coupled glucose transporter SGLT2, and specific inhibitors of SGLT2 are now available to patients with diabetes to increase urinary glucose excretion. Using expression cloning, we identified an accessory protein, 17 kDa membrane-associated protein (MAP17), that increased SGLT2 activity in RNA-injected Xenopus oocytes by two orders of magnitude. Significant stimulation of SGLT2 activity also occurred in opossum kidney cells cotransfected with SGLT2 and MAP17. Notably, transfection with MAP17 did not change the quantity of SGLT2 protein at the cell surface in either cell type. To confirm the physiologic relevance of the MAP17–SGLT2 interaction, we studied a cohort of 60 individuals with familial renal glucosuria. One patient without any identifiable mutation in the SGLT2 coding gene (SLC5A2) displayed homozygosity for a splicing mutation (c.176+1G>A) in the MAP17 coding gene (PDZK1IP1). In the proximal tubule and in other tissues, MAP17 is known to interact with PDZK1, a scaffolding protein linked to other transporters, including Na+/H+ exchanger 3, and to signaling pathways, such as the A-kinase anchor protein 2/protein kinase A pathway. Thus, these results provide the basis for a more thorough characterization of SGLT2 which would include the possible effects of its inhibition on colocalized renal transporters. PMID:27288013

Biliary sphincteroplasty facilitates retrieval of proximally migrated plastic biliary stent.

PubMed

Shah, Dharmesh K; Jain, Samit S; Somani, Piyush O; Rathi, Pravin M

2014-01-01

Proximal migration of biliary stents presents a technical challenge for the therapeutic endoscopist. It may require multiple, complicated corrective procedures resulting in significant morbidity to the patients. In this study we evaluated the utility of balloon biliary sphincteroplasty with CRE (Controlled Radial Expansion) Balloon Dilator on retrieval of proximally migrated biliary stents. We identified patients from our ERCP database who presented with proximal migration of biliary stent, between August 2011 and October 2013. Patients in whom the stent could not be retrieved with conventional methods, balloon sphincteroplasty was performed with a 12 mm CRETM Balloon Dilator (Boston Scientific). Stent removal was attempted with extraction balloon or basket thereafter. We identified 28 patients with proximal migration of biliary stents, placed for benign diseases of the common bile duct. Stent removal was successful in 18 patients (64.28%) with help of an extraction balloon or basket. Of the remaining 10 patients, balloon sphincteroplasty was successfully followed by stent removal in eight patients. Balloon biliary sphincteroplasty increases the success rate of retrieving proximally migrated biliary stents. The procedure is safe, technically easy and yields a good success rate in our experience.

The Applications of Finite Element Analysis in Proximal Humeral Fractures.

PubMed

Ye, Yongyu; You, Wei; Zhu, Weimin; Cui, Jiaming; Chen, Kang; Wang, Daping

2017-01-01

Proximal humeral fractures are common and most challenging, due to the complexity of the glenohumeral joint, especially in the geriatric population with impacted fractures, that the development of implants continues because currently the problems with their fixation are not solved. Pre-, intra-, and postoperative assessments are crucial in management of those patients. Finite element analysis, as one of the valuable tools, has been implemented as an effective and noninvasive method to analyze proximal humeral fractures, providing solid evidence for management of troublesome patients. However, no review article about the applications and effects of finite element analysis in assessing proximal humeral fractures has been reported yet. This review article summarized the applications, contribution, and clinical significance of finite element analysis in assessing proximal humeral fractures. Furthermore, the limitations of finite element analysis, the difficulties of more realistic simulation, and the validation and also the creation of validated FE models were discussed. We concluded that although some advancements in proximal humeral fractures researches have been made by using finite element analysis, utility of this powerful tool for routine clinical management and adequate simulation requires more state-of-the-art studies to provide evidence and bases.

Density and Proximity of Licensed Tobacco Retailers and Adolescent Smoking.

PubMed

Gwon, Seok Hyun; DeGuzman, Pamela B; Kulbok, Pamela A; Jeong, Suyong

2017-02-01

Adolescent smoking prevention is an important issue in health care. This literature review describes the theoretical concept of ecological model for adolescent smoking and tobacco retailers and summarizes previous studies on the association between the density and proximity of tobacco retailers and adolescent smoking. We reviewed nine studies on tobacco retailer density and proximity in relation to adolescent smoking, published in peer-reviewed journals between 2004 and 2014. The tobacco retailer density and proximity were correlated with adolescent lifetime smoking, past 12-month smoking, past 30-day smoking, and susceptibility to smoking. School nurses or other school health professionals may need to include the density and proximity of tobacco retailer factors around schools in school-based tobacco-use prevention programs. Health policy makers may need to consider zoning or licensing restrictions of tobacco retailers around schools for adolescent smoking prevention.

Proximal gastrectomy with jejunal interposition and TGRY anastomosis for proximal gastric cancer.

PubMed

Zhao, Ping; Xiao, Shuo-Meng; Tang, Ling-Chao; Ding, Zhi; Zhou, Xiang; Chen, Xiao-Dong

2014-07-07

To compare the short-term outcomes of patients who underwent proximal gastrectomy with jejunal interposition (PGJI) with those undergoing total gastrectomy with Roux-en-Y anastomosis (TGRY). From January 2009 to January 2011, thirty-five patients underwent PGJI, and forty-one patients underwent TGRY. The surgical efficacy and short-term follow-up outcomes were compared between the two groups. There were no differences in the demographic and clinicopathological characteristics. The mean operation duration and postoperative hospital stay in the PGJI group were statistically longer than those in the TGRY group (P = 0.00). No anastomosis leakage was observed in two groups. No statistically significant difference was found in endoscopic findings, Visick grade or serum albumin level. The single-meal food intake in the PGJI group was more than that in the TGRY group (P = 0.00). The PG group showed significantly better hemoglobin levels in the second year (P = 0.02). The two-year survival rate was not significantly different (PGJI vs TGRY, 93.55% vs 92.5%, P = 1.0). PGJI is a safe, radical surgical method for proximal gastric cancer and leads to better outcomes in terms of the single-meal food intake and hemoglobin level, compared with TGRY in the short term.

Contagion via Magical Thinking and via Mere Proximity.

PubMed

Bower, Lennea R; Peynircioǧlu, Zehra F; Rabinovitz, Brian E

2018-01-01

People show an irrational dislike for objects that were once contaminated or had come into contact with an undesirable person, even if they are currently indistinguishable from other similar objects. To date, such negative contagion within the magical thinking literature has been shown only with inanimate objects. We addressed a boundary condition to see if it also extended to animate targets (dogs and children) while teasing out mere-proximity effects that would predict a similar contagion in the case of children. We used two different types of contagion, one based on proximity and one based on self-information. We found that magical thinking did extend to dogs but not to children when not confounded by mere-proximity effects. Also, contagion was less strong in the case of animate targets, but pity was not related to either this reduction or to the disappearance of the effect with children.

Wall proximity corrections for hot-wire readings in turbulent flows

NASA Technical Reports Server (NTRS)

Hebbar, K. S.

1980-01-01

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

Laparoscopic proximal gastrectomy for gastric neoplasms.

PubMed

Kukar, Moshim; Gabriel, Emmanuel; Ben-David, Kfir; Hochwald, Steven N

2018-06-19

For cancers of the distal gastroesophageal junction or the proximal stomach, proximal gastrectomy can be performed. It is associated with several perioperative benefits compared with total gastrectomy. The use of laparoscopic proximal gastrectomy (LPG) has become an increasingly popular approach for select tumors. We describe our method of LPG, including the preoperative work-up, illustrated depictions of the key steps of the surgery, and our postoperative pathway. A total of 6 patients underwent LPG between July, 2013 to June, 2017. Five patients had early-stage adenocarcinoma, and 1 patient had a gastrointestinal stromal tumor. The median age of the cohort was 70, and each patient had significant comorbidities. Conversion to open was required for 1 patient. All patients had negative final margins and an adequate lymph node dissection (median number of nodes examined was 15, range 12-22). The median postoperative length of stay was 7 days (range 4-7). Two patients developed anastomotic strictures requiring intervention, and 1 patient experienced significant reflux. At a median follow-up of 11 months, there was 1 recurrence. Three patients were alive without evidence of disease, and 2 patients died from other causes. For carefully selected patients, LPG is a safe and reasonable alternative to total gastrectomy, which is associated with similar oncologic outcomes and low morbidity. © 2018 Wiley Periodicals, Inc.

Trans-proximal tubular steady-state concentration differences studied by micro-puncture and tissue content of sodium and chloride at varying intraluminal sodium concentrations in vitro in rat kidney cortex slices: evidence for a multisite sodium transport system.

PubMed Central

Györy, A Z; Roby, H

1977-01-01

1. With the aid of micropuncture techniques, proximal tubular transepithelial concentration differences for Na (deltaC Na) and chloride (deltaC Cl) were measured in kidney cortex slices at bathing fluid Na concentrations from 10 to 400 m-mole. kg-1. Tissue content of water, Na and K was also measured in such slices. Under steady-state conditions of zero net flux of NaCl and water, deltaC Na represents the sum of active Na transport, factored by the tubular permeability coefficient added to a component of flux due to electrical forces. 2. The relation between bathing fluid Na concentraton and deltaC Na appeared sigmoid in form suggesting an allosteric mechanism for the transport step. 3. Transtubular potential difference, calculated from transepithelial Cl distribution ratios, did not appear constant at the various bathing fluid Na concentrations. Correcting for the effect of these potential differences on the value of each deltaC Na did not convert the sigmoid transport curve to a hyperbolic one, confirming the suggested allosteric nature of the active Na transport step. 4. Intracellular Na content varied linearly with bathing fluid Na concentrations implying free entry of this cation into the cell. This also suggests that the sigmoid transport curve is related to the properties of the active Na transport pump. PMID:856986

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

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.

Expandable proximal femoral nail versus gamma proximal femoral nail for the treatment of AO/OTA 31A1-3 fractures.

PubMed

Michael, Drexler; Yaniv, Warschawski; Tal, Frenkel Rutenberg; Kessler Evan, G; Eyal, Amar; Nimrod, Snir; Ehud, Rath; Gilad, Eizenberg; Ely, Steinberg L

2016-02-01

The gamma-proximal femoral nail (GPFN) and the expandable proximal femoral nail (EPFN) are two commonly used intramedullary devices for the treatment of AO 31A1-3 proximal femur fractures. The aim of this study was to compare outcomes and complication rates in patients treated by both devices. A total of 299 patients (149 in the GPFN group and 150 in the EPFN group, average age 83.6 years) were treated for AO 31A1-3 proximal femur fractures in our institution between July 2008 and February 2013. Time from presentation to surgery, level of experience of the surgeon, operative time, amount of blood loss and number of blood transfusions were recorded. Postoperative radiological variables, including peg/screw location, tip to apex distance and orthopaedic complications, as, malunion, nonunion, surgical wound infection rates, cutouts, periprosthetic fractures and the incidence of non-orthopaedic complications. Functional results were estimated using the modified Harris Hip Score, and quality of life was queried by the SF-36 questionnaire. The GPFN and the EPFN fixation methods were similar in terms of functional outcomes, complication rates and quality of life assessments. More patients (107 vs. 73) from the GPFN group were operated within 48 h from presentation (44.8 h vs. 49.9 h for the EPFN group, p=0.351), and their surgery duration and hospitalisation were significantly longer (18.5 days vs. 26 days, respectively, p<0.001). The GPFN patients were frequently operated by junior surgeons: 90% (135) while 50.6% (76) of the EPFN operations were performed by senior doctors. Other intraoperative measures were similar between groups. Cutout was the most common complication affecting 6.7% of the GPFN group and 3.3% of the EPFN group (p=0.182). Good clinical outcomes and low complication rates in the GPFN and the EPFN groups indicate essentially equivalent safety and reliability on the part of both devices for the treatment of proximal femoral fractures. Copyright © 2015

[Avulsion of the Proximal Hamstring Insertion. Case Reports].

PubMed

Mizera, R; Harcuba, R; Kratochvíl, J

2016-01-01

Proximal hamstring avulsion is an uncommon muscle injury with a lack of consensus on indications and the timing and technique of surgery. Poor clinical symptoms and difficulties in the diagnostic process can lead to a false diagnosis. The authors present three cases of proximal hamstring avulsion, two complete and one partial ruptures of the biceps femoris muscle. MRI and ultrasound scans were used for optimal treatment alignment. Acute surgery reconstruction (< 4 weeks) was done in two patients. Re-attachment of the full thickness ruptures was performed to the original place and secured by suture anchors, the partial rupture was fixed by a simple suture. Two patients were free of any symptoms at 6 months after surgery, the last one had pain in the subgluteal area and a mild deficit in hamstring strength. Two interesting systematic reviews published on the treatment of proximal hamstring avulsion are discussed in the final part of the paper. Key words: hamstring, rupture, avulsion.

The shape of the hominoid proximal femur: a geometric morphometric analysis

PubMed Central

Harmon, Elizabeth H

2007-01-01

As part of the hip joint, the proximal femur is an integral locomotor component. Although a link between locomotion and the morphology of some aspects of the proximal femur has been identified, inclusive shapes of this element have not been compared among behaviourally heterogeneous hominoids. Previous analyses have partitioned complex proximal femoral morphology into discrete features (e.g. head, neck, greater trochanter) to facilitate conventional linear measurements. In this study, three-dimensional geometric morphometrics are used to examine the shape of the proximal femur in hominoids to determine whether femoral shape co-varies with locomotor category. Fourteen landmarks are recorded on adult femora of Homo, Pan, Gorilla, Pongo and Hylobates. Generalized Procrustes analysis (GPA) is used to adjust for position, orientation and scale among landmark configurations. Principal components analysis is used to collapse and compare variation in residuals from GPA, and thin-plate spline analysis is used to visualize shape change among taxa. The results indicate that knucklewalking African apes are similar to one another in femoral shape, whereas the more suspensory Asian apes diverge from the African ape pattern. The shape of the human and orangutan proximal femur converge, a result that is best explained in terms of the distinct requirements for locomotion in each group. These findings suggest that the shape of the proximal femur is brought about primarily by locomotor behaviour. PMID:17310545

Proximity to sports facilities and sports participation for adolescents in Germany.

PubMed

Reimers, Anne K; Wagner, Matthias; Alvanides, Seraphim; Steinmayr, Andreas; Reiner, Miriam; Schmidt, Steffen; Woll, Alexander

2014-01-01

To assess the relationship between proximity to specific sports facilities and participation in the corresponding sports activities for adolescents in Germany. A sample of 1,768 adolescents aged 11-17 years old and living in 161 German communities was examined. Distances to the nearest sports facilities were calculated as an indicator of proximity to sports facilities using Geographic Information Systems (GIS). Participation in specific leisure-time sports activities in sports clubs was assessed using a self-report questionnaire and individual-level socio-demographic variables were derived from a parent questionnaire. Community-level socio-demographics as covariates were selected from the INKAR database, in particular from indicators and maps on land development. Logistic regression analyses were conducted to examine associations between proximity to the nearest sports facilities and participation in the corresponding sports activities. The logistic regression analyses showed that girls residing longer distances from the nearest gym were less likely to engage in indoor sports activities; a significant interaction between distances to gyms and level of urbanization was identified. Decomposition of the interaction term showed that for adolescent girls living in rural areas participation in indoor sports activities was positively associated with gym proximity. Proximity to tennis courts and indoor pools was not associated with participation in tennis or water sports, respectively. Improved proximity to gyms is likely to be more important for female adolescents living in rural areas.

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

Proximate Composition, Amino Acid, Mineral, and Heavy Metal Content of Dried Laver

PubMed Central

Hwang, Eun-Sun; Ki, Kyung-Nam; Chung, Ha-Yull

2013-01-01

Laver, a red algae belonging to the genus Porphyra, is one of the most widely consumed edible seaweeds. The most popular commercial dried laver species, P. tenera and P. haitanensis, were collected from Korea and China, respectively, and evaluated for proximate composition, amino acids, minerals, trace heavy metals, and color. The moisture and ash contents of P. tenera and P. haitanensis ranged from 3.66~6.74% and 8.78~9.07%, respectively; crude lipid and protein contents were 1.96~2.25% and 32.16~36.88%, respectively. Dried lavers were found to be a good source of amino acids, such as asparagine, isoleucine, leucine, and taurine, and γ-aminobutyric acid. K, Ca, Mg, Na, P, I, Fe, and Se minerals were selected for analysis. A clear regional variation existed in the amino acid, mineral, and trace metal contents of lavers. Regular consumption of lavers may have heath benefits because they are relatively low in fat and high in protein, and contain functional amino acids and minerals. PMID:24471123

Proximate composition, amino Acid, mineral, and heavy metal content of dried laver.

PubMed

Hwang, Eun-Sun; Ki, Kyung-Nam; Chung, Ha-Yull

2013-06-01

Laver, a red algae belonging to the genus Porphyra, is one of the most widely consumed edible seaweeds. The most popular commercial dried laver species, P. tenera and P. haitanensis, were collected from Korea and China, respectively, and evaluated for proximate composition, amino acids, minerals, trace heavy metals, and color. The moisture and ash contents of P. tenera and P. haitanensis ranged from 3.66~6.74% and 8.78~9.07%, respectively; crude lipid and protein contents were 1.96~2.25% and 32.16~36.88%, respectively. Dried lavers were found to be a good source of amino acids, such as asparagine, isoleucine, leucine, and taurine, and γ-aminobutyric acid. K, Ca, Mg, Na, P, I, Fe, and Se minerals were selected for analysis. A clear regional variation existed in the amino acid, mineral, and trace metal contents of lavers. Regular consumption of lavers may have heath benefits because they are relatively low in fat and high in protein, and contain functional amino acids and minerals.

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.

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

PubMed

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.

Clinical relevance of valgus deformity of proximal femur in cerebral palsy.

PubMed

Lee, Kyoung Min; Kang, Jong Yeol; Chung, Chin Youb; Kwon, Dae Gyu; Lee, Sang Hyeong; Choi, In Ho; Cho, Tae-Joon; Yoo, Won Joon; Park, Moon Seok

2010-01-01

Proximal femoral deformity related to physis has not been studied in patients with cerebral palsy (CP). This study was performed to investigate the clinical relevance of neck shaft angle (NSA), head shaft angle (HSA), and proximal femoral epiphyseal shape in patients with CP, which represent the deformities of metaphysis, physis, and epiphysis, respectively. Three hundred eighty-four patients with CP (mean age 9.1 y, 249 males and 135 females) were included. Extent of involvement and functional states [Gross Motor Function Classification System (GMFCS) level] were obtained. Radiographic measurements including NSA, HSA, and qualitative shape of the proximal femoral epiphysis were evaluated and analyzed according to extent of involvement and GMFCS level. Reliability and correlation with each measurement were assessed. Multiple regression test was performed to examine the significant contributing factors to migration percentage (MP) that represents hip instability. NSA showed excellent interobserver reliability with intraclass correlation coefficients of 0.976. Correlation with the MP was higher in the NSA (r=0.419, P<0.001) than in the HSA (r=0.256, P<0.001). NSA, HSA, and MP tended to increase with increasing GMFCS level, and proportion of valgus deformed proximal femoral epiphysis also increased with increasing GMFCS level, which means valgus deformity and unstable hips in the less favorable functional states. Multiple regression analysis revealed NSA, GMFCS level, and shape of the proximal femoral epiphysis to be significant factors affecting MP. NSA appeared to be more clinically relevant than HSA in evaluating proximal femoral deformity in patients with CP. Shape of proximal femoral epiphysis is believed to have clinical implications in terms of hip instability. Diagnostic level II.

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.

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.

Airborne Proximity Warning Instrument Laboratory Tests

DOT National Transportation Integrated Search

1977-01-01

An Airborne Proximity Warning Instrument (APWI) designed and manufactured by Rock Avionics, New York, was subjected to a short laboratory test at the Transportation Systems Center to determine the suitability of this product for further evaluation as...

DO PROXIMAL AND DISTAL GASTRIC TUMOURS BEHAVE DIFFERENTLY?

PubMed Central

da COSTA, Laurence Bedin; TONETO, Marcelo Garcia; MOREIRA, Luis Fernando

2016-01-01

ABSTRACT Background: Although the incidence of gastric (adenocarcinoma) cancer has been decreasing over time, it is still one of the most common malignancies worldwide, and proximal tumours tend to have a worse prognosis. Aim: To compare surgical outcomes and prognosis between proximal - excluding tumours of the cardia - and distal gastric cancer. Methods: Out of 293 cases reviewed - 209 with distal and 69 with proximal gastric cancer - were compared for clinical and pathological features, stage, surgical outcome, mortality and survival. Results: Statistically, there was no significant difference between patients in both groups regarding mortality (p=0.661), adjuvant chemotherapy (p 0.661), and radiation (p=1.000). However, there was significant difference in the degree of lymph node dissection employed (p=0.002) and the number of positive lymph nodes resected (p=0.038) between the two groups. The odds of death at five years for patients who had a D0 dissection was three times greater (odds ratio 2.78; (95%CI 1.33-5.82) than that for patients who had a D2 dissection, while for patients who had a D1 dissection the odds ratio was only 1.41 (95%CI 0.71-2.83) compared to D2-dissected patients. Conclusion: Although no significant differences were found between proximal and distal gastric cancer, the increased risk of death in D0- and D1-dissected patients clearly suggests an important role of radical D2 lymph node dissection in survival. PMID:28076476

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. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

Proximity functions for electrons up to 10 keV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chmelevsky, D.; Kellerer, A.M.; Terrissol, M.

1980-11-01

Proximity functions for electrons up to 10 keV in water are computed from simulated particle tracks. Numerical results are given for the differential functions t(x) and the integral functions T(x). Basic characteristics of these functions and their connections to other microdosimetric quantities are considered. As an example of the applicability of the proximity functions, the quantity y/sub D/ for spheres is derived from t(x).

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chkhalo, N. I.; Salashchenko, N. N.; Sherbakov, A. V., E-mail: SherbakovAV@ipm.sci-nnov.ru

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 lensesmore » 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.« less

Morality, responsibility and risk: negative gay men's perceived proximity to HIV.

PubMed

Keogh, Peter

2008-05-01

In order to examine the ways in which men's perceptions of their social surroundings influence how they experience and negotiate sexual risk, we conducted a qualitative study with 36 men who lived in London or Birmingham, had five or more male partners in the previous year and believed themselves to be HIV negative. Men were recruited into two sub-samples (18 men each). The high proximity group personally knew someone with HIV and had a positive sexual partner in the year prior to interview. The low proximity group had never personally known anyone with HIV and had never had a sexual partner who they knew or believed to be HIV positive. Data was collected via semi-structured interviews. Men in the low proximity groups used moral discourses to articulate beliefs and social norms around the disclosure of HIV which may act as a deterrent to sexual partners disclosing. Although most expected positive sexual partners to disclose, they had difficulty in articulating how they would respond to disclosure and how they would manage any consequent sexual risk. For the men in the high proximity group, living around HIV constituted a part of everyday life. Disclosure and discussion of HIV did not violate their social norms. The majority did not expect positive sexual partners to disclose to them and knew how they would respond to such disclosure if it occurred. Men in this group did not use moral discourses but talked practically about better and worse ways of managing disclosure. Proximity to HIV is mediated by strong social norms and self-perpetuating moral discourses which effectively creates a social divide between men who perceive themselves to be in low proximity to HIV and their HIV positive contacts and sexual partners. Men with perceived low proximity to HIV are appropriate as a target group for HIV prevention.

Proximity to Sports Facilities and Sports Participation for Adolescents in Germany

PubMed Central

Reimers, Anne K.; Wagner, Matthias; Alvanides, Seraphim; Steinmayr, Andreas; Reiner, Miriam; Schmidt, Steffen; Woll, Alexander

2014-01-01

Objectives To assess the relationship between proximity to specific sports facilities and participation in the corresponding sports activities for adolescents in Germany. Methods A sample of 1,768 adolescents aged 11–17 years old and living in 161 German communities was examined. Distances to the nearest sports facilities were calculated as an indicator of proximity to sports facilities using Geographic Information Systems (GIS). Participation in specific leisure-time sports activities in sports clubs was assessed using a self-report questionnaire and individual-level socio-demographic variables were derived from a parent questionnaire. Community-level socio-demographics as covariates were selected from the INKAR database, in particular from indicators and maps on land development. Logistic regression analyses were conducted to examine associations between proximity to the nearest sports facilities and participation in the corresponding sports activities. Results The logisitic regression analyses showed that girls residing longer distances from the nearest gym were less likely to engage in indoor sports activities; a significant interaction between distances to gyms and level of urbanization was identified. Decomposition of the interaction term showed that for adolescent girls living in rural areas participation in indoor sports activities was positively associated with gym proximity. Proximity to tennis courts and indoor pools was not associated with participation in tennis or water sports, respectively. Conclusions Improved proximity to gyms is likely to be more important for female adolescents living in rural areas. PMID:24675689

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.

SINA: A test system for proximity fuses

NASA Astrophysics Data System (ADS)

Ruizenaar, M. G. A.

1989-04-01

SINA, a signal generator that can be used for testing proximity fuses, is described. The circuitry of proximity fuses is presented; the output signal of the RF circuit results from a mixing of the emitted signal and received signal that is Doppler shifted in frequency by the relative motion of the fuse with respect to the reflecting target of surface. With SINA, digitized and stored target and clutter signals (previously measured) can be transformed to Doppler signals, for example during a real flight. SINA can be used for testing fuse circuitry, for example in the verification of results of computer simulations of the low frequency Doppler signal processing. The software of SINA and its use are explained.

Predictive risk models for proximal aortic surgery

PubMed Central

Díaz, Rocío; Pascual, Isaac; Álvarez, Rubén; Alperi, Alberto; Rozado, Jose; Morales, Carlos; Silva, Jacobo; Morís, César

2017-01-01

Predictive risk models help improve decision making, information to our patients and quality control comparing results between surgeons and between institutions. The use of these models promotes competitiveness and led to increasingly better results. All these virtues are of utmost importance when the surgical operation entails high-risk. Although proximal aortic surgery is less frequent than other cardiac surgery operations, this procedure itself is more challenging and technically demanding than other common cardiac surgery techniques. The aim of this study is to review the current status of predictive risk models for patients who undergo proximal aortic surgery, which means aortic root replacement, supracoronary ascending aortic replacement or aortic arch surgery. PMID:28616348

Allograft-prosthesis composites after bone tumor resection at the proximal tibia.

PubMed

Biau, David Jean; Dumaine, Valérie; Babinet, Antoine; Tomeno, Bernard; Anract, Philippe

2007-03-01

The survival of irradiated allograft-prosthesis composites at the proximal tibia is mostly unknown. However, allograft-prosthesis composites have proved beneficial at other reconstruction sites. We presumed allograft-prosthesis composites at the proximal tibia would improve survival and facilitate reattachment of the extensor mechanism compared with that of conventional (megaprostheses) reconstructions. We retrospectively reviewed 26 patients who underwent resection of proximal tibia tumors followed by reconstruction with allo-graft-prosthesis composites. Patients received Guepar massive custom-made fully constrained prostheses. Allografts were sterilized with gamma radiation, and the stems were cemented into the allograft and host bone. The minimum followup was 6 months (median, 128 months; range, 6-195 months). Fourteen patients had one or more components removed. The median allograft-prosthesis composite survival was 102 months (95% confidence interval, 64.2-infinity). Of the 26 allografts, seven fractured, six showed signs of partial resorption, and six had infections develop. Seven allografts showed signs of fusion with the host bone. Six extensor mechanism reconstructions failed. Allograft-prosthesis composites sterilized by gamma radiation yielded poor results for proximal tibial reconstruction as complications and failures were common. We do not recommend irradiated allograft-prosthesis composites for proximal tibia reconstruction.

Dirac-electron-mediated magnetic proximity effect in topological insulator/magnetic insulator heterostructures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Mingda; Song, Qichen; Zhao, Weiwei

The possible realization of dissipationless chiral edge current in a topological insulator/magnetic insulator heterostructure is based on the condition that the magnetic proximity exchange coupling at the interface is dominated by the Dirac surface states of the topological insulator. We report a polarized neutron reflectometry observation of Dirac-electron-mediated magnetic proximity effect in a bulk-insulating topological insulator (Bi 0.2Sb 0.8) 2Te 3/magnetic insulator EuS heterostructure. We are able to maximize the proximity-induced magnetism by applying an electrical back gate to tune the Fermi level of topological insulator to be close to the Dirac point. A phenomenological model based on diamagnetic screeningmore » is developed to explain the suppressed proximity-induced magnetism at high carrier density. Our work paves the way to utilize the magnetic proximity effect at the topological insulator/magnetic insulator heterointerface for low-power spintronic applications.« less

Dirac-electron-mediated magnetic proximity effect in topological insulator/magnetic insulator heterostructures

DOE PAGES

Li, Mingda; Song, Qichen; Zhao, Weiwei; ...

2017-11-01

The possible realization of dissipationless chiral edge current in a topological insulator/magnetic insulator heterostructure is based on the condition that the magnetic proximity exchange coupling at the interface is dominated by the Dirac surface states of the topological insulator. We report a polarized neutron reflectometry observation of Dirac-electron-mediated magnetic proximity effect in a bulk-insulating topological insulator (Bi 0.2Sb 0.8) 2Te 3/magnetic insulator EuS heterostructure. We are able to maximize the proximity-induced magnetism by applying an electrical back gate to tune the Fermi level of topological insulator to be close to the Dirac point. A phenomenological model based on diamagnetic screeningmore » is developed to explain the suppressed proximity-induced magnetism at high carrier density. Our work paves the way to utilize the magnetic proximity effect at the topological insulator/magnetic insulator heterointerface for low-power spintronic applications.« less

Understanding Proximal-Distal Economic Projections of the Benefits of Childhood Preventive Interventions

PubMed Central

Slade, Eric P.; Becker, Kimberly D.

2014-01-01

This paper discusses the steps and decisions involved in proximal-distal economic modeling, in which social, behavioral, and academic outcomes data for children may be used to inform projections of the economic consequences of interventions. Economic projections based on proximal-distal modeling techniques may be used in cost-benefit analyses when information is unavailable for certain long term outcomes data in adulthood or to build entire cost-benefit analyses. Although examples of proximal-distal economic analyses of preventive interventions exist in policy reports prepared for governmental agencies, such analyses have rarely been completed in conjunction with research trials. The modeling decisions on which these prediction models are based are often opaque to policymakers and other end-users. This paper aims to illuminate some of the key steps and considerations involved in constructing proximal-distal prediction models and to provide examples and suggestions that may help guide future proximal-distal analyses. PMID:24337979

Arteriovenous Hybrid Graft with Outflow in the Proximal Axillary Vein.

PubMed

Murga, Allen G; Chiriano, Jason; Kiang, Sharon C; Patel, Sheela; Bianchi, Christian; Abou-Zamzam, Ahmed M; Teruya, Theodore H

2017-07-01

The patency of long-term hemodialysis access in end-stage renal disease patients remains a significant challenge. Often these patients are affected with limited venous outflow options, requiring limb abandonment, and creation of new access in the contralateral arm. Vascular surgeons are familiar with the exposure of the proximal axillary artery via an infraclavicular incision. The axillary vein is easily exposed through this technique. The use of the hybrid Gore graft can make the venous anastomosis easier. A hybrid graft with its venous outflow placed in the proximal axillary vein can extend the options of upper extremity access procedures. We reviewed our early experience with this technique. A review of dialysis procedures at the Loma Linda VA was performed. All patients undergoing placement of arteriovenous grafts utilizing the Gore hybrid placed into the proximal axillary vein for outflow were identified. Outcomes in terms of primary and secondary patency rates were determined. Eight patients had placement of an arteriovenous hybrid graft in the proximal axillary vein via an infraclavicular incision. All patients had exhausted other options for hemodialysis access in the ipsilateral upper extremity. All grafts were used successfully for dialysis. The mean primary and secondary patency rates at 6 months were 37.5% and 62.5%, respectively. One patient developed steal syndrome, requiring proximalization of the graft. Seven out of the 8 patients required secondary procedures including thrombectomy (n = 16) and angioplasty (n = 17). Placement of a hybrid graft in the proximal axillary vein is an effective and suitable option for patients who have exhausted arteriovenous access sites in the arm. This procedure can easily be performed in an outpatient setting with a low complication rate and allowing for preservation of the contralateral upper extremity for future use. Published by Elsevier Inc.

Intramedullary Percutaneous Fixation of Extra-Articular Proximal and Middle Phalanx Fractures.

PubMed

Jovanovic, Nebojsa; Aldlyami, Ehab; Saraj, Basem; Fm Seidam, Mohamed; Badawi, Hamed; Shaat, Ahmed; Alawadi, Khalid; Dodakundi, Chaitanya

2018-06-01

Multiple methods have been described for treating unstable proximal and middle phalangeal fractures. Irrespective of using an open or closed technique of fixation, stiffness and extensor lag at the proximal/distal interphalangeal joint almost always occur. This issue can be avoided by allowing the patients to mobilize the fingers out of plaster or splint as early as possible from the day of surgery. We describe a technique of intramedullary percutaneous fixation of extra-articular proximal and middle phalanx fractures allowing immediate mobilization of fingers, concurrent stabilization with progressive healing and thus preventing such complications.

Computerized classification of proximal occlusion in the left anterior descending coronary artery.

PubMed

Gregg, Richard E; Nikus, Kjell C; Zhou, Sophia H; Startt Selvester, Ronald H; Barbara, Victoria

2010-01-01

Proximal occlusion within the left anterior descending (LAD) coronary artery in patients with acute myocardial infarction leads to higher mortality than does nonproximal occlusion. We evaluated an automated program to detect proximal LAD occlusion. All patients with suspected acute coronary syndrome (n = 7,710) presenting consecutively to the emergency department of a local hospital with a coronary angiogram–confirmed flow-limiting lesion and notation of occlusion site were included in the study (n = 711). Electrocardiograms (ECGs) that met ST-segment elevation myocardial infarction (STEMI) criteria were included in the training set (n = 183). Paired angiographic location of proximal LAD and ECGs with ST elevation in the anterolateral region were used for the computer program development (n = 36). The test set was based on ECG criteria for anterolateral STEMI only without angiographic reports (n = 162). Tested against 2 expert cardiologists' agreed reading of proximal LAD occlusion, the algorithm has a sensitivity of 95% and a specificity of 82%. The algorithm is designed to have high sensitivity rather than high specificity for the purpose of not missing any proximal LAD in the STEMI population. Our preliminary evaluation suggests that the algorithm can detect proximal LAD occlusion as an additional interpretation to STEMI detection with similar accuracy as cardiologist readers.

Proximity Analysis and the Structure of Organization in Free Recall.

ERIC Educational Resources Information Center

Friendly, Michael L.

A method for assessing the structure of organization was developed on the basis of the ordinal separation, or proximity, between pairs ot items in recall protocols over a series of trials. The proximity measure is based on the assumption, common to all indices of organization, that items which are coded together in subjective memory units will…

Treatment of proximal ulna and olecranon fractures by dorsal plating.

PubMed

Kloen, Peter; Buijze, Geert A

2009-12-01

Anatomic reconstruction of proximal ulna and olecranon fractures allowing early mobilization and prevention of ulnohumeral arthritis. Comminuted olecranon or proximal ulna fractures (including Monteggia fractures), olecranon fractures extending distally from the coronoid process, nonunions of the proximal ulna, segmental fractures of the proximal ulna extending into the shaft, fractures of the proximal ulna associated with a coronoid fracture. Patients in poor general condition. Soft-tissue defects around the elbow preventing wound closure over the plate. Pediatric fractures with open growth plates where screws would cross the physis. Posterior approach to the elbow. Hinging the fracture site open by extension of the proximal fragment based on triceps insertion. Fracture involvement of the coronoid with a large displaced fracture fragment can generally be reduced through the fracture side. Reconstruction with temporary Kirschner wires. Fixation by placing a (precontoured) plate around the tip of the olecranon with a long intramedullary screw and orthogonal (uni)cortical screws in the shaft. Radial head pathology can be addressed - if needed - through the same incision. Internal fixation, resection or prosthetic replacement of the radial head is done based on injury pattern/stability. Functional rehabilitation using active assisted range of motion of the elbow may be started immediately out of splint. Posterior splint for 7-10 days to allow wound healing. Between 2003 and July 2008, 26 patients were treated with posterior plating of the proximal ulna and olecranon using this strategy. There were 23 acute fractures (of which one was referred for revision after suboptimal fixation a few days earlier), one nonunion that became traumatized, and two nascent malunions. A midline posterior approach allowed addressing both ulna and radial head pathology. The plate was contoured to wrap around the olecranon. All fractures healed. There were one postoperative infection, one

ANALYSIS OF METHODS FOR DETECTING THE PROXIMITY EFFECT IN QUASAR SPECTRA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall'Aglio, Aldo; Gnedin, Nickolay Y., E-mail: adaglio@aip.d

Using numerical simulations of structure formation, we investigate several methods for determining the strength of the proximity effect in the H I Ly{alpha} forest. We analyze three high-resolution ({approx}10 kpc) redshift snapshots (z-bar=4,3, and 2.25) of a Hydro-Particle-Mesh simulation to obtain realistic absorption spectra of the H I Ly{alpha} forest. We model the proximity effect along the simulated sight lines with a simple analytical prescription based on the assumed quasar luminosity and the intensity of the cosmic UV background (UVB). We begin our analysis investigating the intrinsic biases thought to arise in the widely adopted standard technique of combining multiplemore » lines of sight when searching for the proximity effect. We confirm the existence of these biases, albeit smaller than previously predicted with simple Monte Carlo simulations. We then concentrate on the analysis of the proximity effect along individual lines of sight. After determining its strength with a fiducial value of the UVB intensity, we construct the proximity effect strength distribution (PESD). We confirm that the PESD inferred from the simple averaging technique accurately recovers the input strength of the proximity effect at all redshifts. Moreover, the PESD closely follows the behaviors found in observed samples of quasar spectra. However, the PESD obtained from our new simulated sight lines presents some differences to that of simple Monte Carlo simulations. At all redshifts, we find a smaller dispersion of the strength parameters, the source of the corresponding smaller biases found when combining multiple lines of sight. After developing three new theoretical methods for recovering the strength of the proximity effect on individual lines of sight, we compare their accuracy to the PESD from the simple averaging technique. All our new approaches are based on the maximization of the likelihood function, albeit invoking some modifications. The new techniques presented

Proximal hamstring tendinopathy: results of surgical management and histopathologic findings.

PubMed

Lempainen, Lasse; Sarimo, Janne; Mattila, Kimmo; Vaittinen, Samuli; Orava, Sakari

2009-04-01

Tendon disorders are common problems in sports and are known to be difficult to treat. Only limited information is available concerning treatment of proximal hamstring tendinopathy. To the authors' knowledge, no histopathologic findings of proximal hamstring tendinosis have been published. Surgery (semimembranosus tenotomy and exploration of the sciatic nerve) is an effective treatment for proximal hamstring tendinopathy. Case series; Level of evidence, 4. A total of 103 cases of proximal hamstring tendinopathy in athletes (58 men, 32 women; 13 bilateral operations) with surgical treatment were included. The cases were retrospectively analyzed, and a 4-category rating system was used to evaluate the overall result. At the follow-up, the patients were asked about possible symptoms and their return to sports. Biopsy samples from 15 of the operated tendons were taken and analyzed by a pathologist. The average follow-up was 49 months (range, 12-156 months). The result was evaluated to be excellent in 62 cases, good in 30, fair in 5, and poor in 6. After surgery, 80 of the 90 patients were able to return to the same level of sporting activity as before the onset of the symptoms. This took a mean of 5 months (range, 2-12 months). Typical morphologic findings of tendinosis were found in all biopsy specimens. Given the good functional outcome and low complication rate, the authors present surgical treatment as a valuable option in proximal hamstring tendinopathy if conservative treatment fails.

Residential proximity to major roads and placenta/birth weight ratio.

PubMed

Yorifuji, Takashi; Naruse, Hiroo; Kashima, Saori; Murakoshi, Takeshi; Tsuda, Toshihide; Doi, Hiroyuki; Kawachi, Ichiro

2012-01-01

Exposure to air pollution has been demonstrated to increase the risk of preterm birth and low birth weight. We examined whether proximity to major roads (as a marker of exposure to air pollution) is associated with increased placenta/birth weight ratio (as a biomarker of the placental transport function). Data on parental characteristics and birth outcomes were extracted from the database maintained by a major hospital in Shizuoka Prefecture, Japan. We restricted the analysis to mothers who delivered liveborn single births from 1997 to 2008 (n = 14,189). Using geocoded residential information, each birth was classified according to proximity to major roads. We examined the association between proximity to major roads and the placenta/birth weight ratio, using multiple linear regression. Proximity to major roads was associated with higher placenta/birth weight ratio. After adjusting for potential confounders, living within 200 m of a major road increased the ratio by 0.48% (95% CI = 0.15 to 0. 80). In addition, proximity to major roads was associated with lower placenta weight and birth weight. These observed associations were stronger among participants living closer to major roads. Exposure to traffic-related air pollution is associated with higher placenta/birth weight ratio. Impaired placental oxygen and nutrient transport function might be a mechanism for explaining the observed association between air pollution and low birth weight as well as preterm birth. Copyright © 2011 Elsevier B.V. All rights reserved.

Acquired Fanconi syndrome with proximal tubular cytoplasmic fibrillary inclusions of λ light chain restriction.

PubMed

Yao, Ying; Wang, Su-Xia; Zhang, You-Kang; Wang, Yan; Liu, Li; Liu, Gang

2014-01-01

Light chain proximal tubulopathy is a rarely reported entity associated with plasma cell dyscrasia that classically manifests as acquired Fanconi syndrome and is characterized by the presence of κ-restricted crystals in the proximal tubular cytoplasm. We herein present a case of multiple myeloma with Fanconi syndrome and acute kidney injury due to light chain proximal tubulopathy with light chain cast nephropathy. Prominent phagolysosomes and numerous irregularly shaped inclusions with a fibrillary matrix in the cytoplasm of the proximal tubules were identified on electron microscopy. A monotypic light chain of the λ type was detected in the distal tubular casts, proximal tubular cytoplasmic lysosomes and fibrillary inclusions on immunofluorescence and immune electron microscopy. This case underscores the importance of conducting careful ultrastructural investigations and immunocytologic examinations of light chains for detecting and diagnosing light chain proximal tubulopathy.

[Augmentation technique on the proximal humerus].

PubMed

Scola, A; Gebhard, F; Röderer, G

2015-09-01

The treatment of osteoporotic fractures is still a challenge. The advantages of augmentation with respect to primary in vitro stability and the clinical use for the proximal humerus are presented in this article. In this study six paired human humeri were randomized into an augmented and a non-augmented group. Osteosynthesis was performed with a PHILOS plate (Synthes®). In the augmented group the two screws finding purchase in the weakest cancellous bone were augmented. The specimens were tested in a 3-part fracture model in a varus bending test. The augmented PHILOS plates withstood significantly more load cycles until failure. The correlation to bone mineral density (BMD) showed that augmentation could partially compensate for low BMD. The augmentation of the screws in locked plating in a proximal humerus fracture model is effective in improving the primary stability in a cyclic varus bending test. The targeted augmentation of two particular screws in a region of low bone quality within the humeral head was almost as effective as four screws with twice the amount of bone cement. Screw augmentation combined with a knowledge of the local bone quality could be more effective in enhancing the primary stability of a proximal humerus locking plate because the effect of augmentation can be exploited more effectively limiting it to the degree required. The technique of augmentation is simple and can be applied in open and minimally invasive procedures. When the correct procedure is used, complications (cement leakage into the joint) can be avoided.

How to improve outcome in surgery for Proximal Hypospadias?

PubMed

Qureshi, Abdul Hafeez; Zaidi, Syed Zafar

2016-02-01

To evaluate the role of subdartos fascial tissue as watertight layer in improving outcome for 2-stage proximal hypospadias surgery. The experimental study was conducted at the Department of Urology, Indus Hospital, Karachi, and comprised an audit of patients with proximal hypospadias who underwent surgery from July 1, 2007, to December 31, 2011. The initial two-stage repair of proximal hypospadias led to a high rate of urethrocutanous fistula formation (Group A), and, thus, a modification was introduced and subdartos facial double layer was applied over the urethral suture line (Group B). The results were compared regarding age, type of hypospadias, graft failure and urethrocutanous fistula in these patients. There were 27 patients in Group A and 16(59.3%) of them ended up having urethrocutanous fistula. Group B had 25 patients and only 2(8%) had fistula formation. The application of dartos facial flap waterproofing layer reduced fistula rate.

Proximal femoral fractures.

PubMed

Webb, Lawrence X

2002-01-01

Fractures of the proximal femur include fractures of the head, neck, intertrochanteric, and subtrochanteric regions. Head fractures commonly accompany dislocations. Neck fractures and intertrochanteric fractures occur with greatest frequency in elderly patients with a low bone mineral density and are produced by low-energy mechanisms. Subtrochanteric fractures occur in a predominantly strong cortical osseous region which is exposed to large compressive stresses. Implants used to address these fractures must be able to accommodate significant loads while the fractures consolidate. Complications secondary to these injuries produce significant morbidity and include infection, nonunion, malunion, decubitus ulcers, fat emboli, deep venous thrombosis, pulmonary embolus, pneumonia, myocardial infarction, stroke, and death.

Colonic injuries (primary repair and proximal colostomy).

PubMed

Tripathi, Munishwar D; Mishra, Brijesh

2005-01-01

This paper compares the outcome of colonic injuries (primary repair and proximal colostomy) in 94 cases. It concludes that certain risk factors are of predictive value in case of colon injuries (eg, gross fecal contamination, more than two visceral injuries, more than four units of blood transfusion, and extensive colonic injuries) irrespective of type of operation performed. Primary repair is debatable; however, in the present antibiotic era, it is safe and less costly than the two-stage procedure of proximal colostomy with repair. Primary repair can be performed in almost all cases except in certain selected cases that are decided on the table, taking into account the above risks factors. Mortality in cases of colonic injuries is associated with risk factors rather than colonic injury itself.

Proximity-driven enhanced magnetic order at ferromagnetic-insulator-magnetic-topological-insulator interface

DOE PAGES

Li, Mingda; Zhu, Yimei; Chang, Cui -Zu; ...

2015-08-17

Magnetic exchange driven proximity effect at a magnetic-insulator–topological-insulator (MI-TI) interface provides a rich playground for novel phenomena as well as a way to realize low energy dissipation quantum devices. In this study, we report a dramatic enhancement of proximity exchange coupling in the MI/magnetic-TI EuS/Sb 2–xV xTe 3 hybrid heterostructure, where V doping is used to drive the TI (Sb 2Te 3) magnetic. We observe an artificial antiferromagneticlike structure near the MI-TI interface, which may account for the enhanced proximity coupling. The interplay between the proximity effect and doping in a hybrid heterostructure provides insights into the engineering of magneticmore » ordering.« less

Percutaneous insertion of a proximal humeral locking plate: an anatomic study.

PubMed

Smith, Jason; Berry, Greg; Laflamme, Yves; Blain-Pare, Etienne; Reindl, Rudy; Harvey, Edward

2007-02-01

This cadaveric study sought to evaluate the feasibility of applying a locking proximal humerus plate with a novel minimally invasive technique. A unique pre-contoured locking plate was placed on cadaveric proximal humeri through a described minimally invasive approach. Proximity of the plate and screws to the axillary nerve and their respective surgical tracks were quantified. Safe screw hole placement with respect to the axillary nerve was determined. Risk of entrapment of the nerve beneath the plate was evaluated. Three of the holes near the middle of the locking plate consistently intersected the course of the axillary nerve and were unsafe for percutaneous placement of the screws. The axillary nerve could be palpated during the course of surgery and easily protected from injury. No entrapment of the axillary nerve occurred using this minimally invasive technique. The screw-in locking guide cannot be used with this technique as it caused tenting of the axillary nerve. Placement of a locking proximal humerus plate via a minimally invasive lateral trans-deltoid approach is safe if the locking screws are limited to superior and inferior holes. This can be done safely without entrapment of the axillary beneath the plate. Plate fixation of proximal humerus fractures may now be more desirable with the use of this approach.

Fluoroscopically Guided Peritendinous Corticosteroid Injection for Proximal Hamstring Tendinopathy: A Retrospective Review.

PubMed

Nicholson, Luke T; DiSegna, Steven; Newman, Joel S; Miller, Suzanne L

2014-03-01

Proximal hamstring tendinopathy is an uncommon but debilitating cause of posterior thigh pain in athletes subjected to repetitive eccentric hamstring contraction, such as runners. Minimal data exist evaluating treatment options for proximal hamstring tendinopathy. This retrospective study evaluates the effectiveness of fluoroscopically guided corticosteroid injections in treating proximal hamstring tendinopathy. Case series; Level of evidence, 4. Eighteen athletes with 22 cases of magnetic resonance imaging-confirmed proximal hamstring tendinopathy were treated with corticosteroid injection and later contacted to evaluate the efficacy of the injection with the use of a questionnaire. The visual analog score decreased from 7.22 preinjection to 3.94 postinjection (P < .001), level of athletic participation increased from 28.76% to 68.82% (P < .001) at a mean follow-up of 21 months, and 38.8% of patients experienced complete resolution at a mean follow-up of 24.8 months. The mean lower extremity function score at the time of follow-up was 60. A trial of fluoroscopically guided corticosteroid injection is warranted in patients presenting with symptoms of proximal hamstring tendinopathy refractory to conservative therapy.

In vitro Culture of Naïve Human Bone Marrow Mesenchymal Stem Cells: A Stemness Based Approach

PubMed Central

Pal, Bidisha; Das, Bikul

2017-01-01

Human bone marrow derived mesenchymal stem cells (BM-MSCs) resides in their niches in close proximity to hematopoietic stem cells (HSCs). These naïve MSCs have tremendous potential in regenerative therapeutics, and may also be exploited by cancer and infectious disease agents. Hence, it is important to study the physiological and pathological roles of naïve MSC. However, our knowledge of naïve MSCs is limited by lack of appropriate isolation and in vitro culture methods. Established culture methods use serum rich media, and serial passaging for retrospective isolation of MSCs. These primed MSCs may not reflect the true physiological and pathological roles of naive MSCs (Figure 1). Therefore, there is a strong need for direct isolation and in vitro culture of naïve MSCs to study their stemness (self-renewal and undifferentiated state) and developmental ontogeny. We have taken a niche-based approach on stemness to better maintain naïve MSCs in vitro. In this approach, stemness is broadly divided as niche dependent (extrinsic), niche independent (intrinsic) and niche modulatory (altruistic or competitive). Using this approach, we were able to maintain naïve CD271+/CD133+ BM-MSCs for 2 weeks. Furthermore, this in vitro culture system helped us to identify naïve MSCs as a protective niche site for Mycobacterium tuberculosis, the causative organism of pulmonary tuberculosis. In this review, we discuss the in vitro culture of primed vs. naïve human BM derived MSCs with a special focus on how a stemness based approach could facilitate the study of naïve BM-MSCs. PMID:28884113

Scaling a Conditional Proximity Matrix to Symmetry.

ERIC Educational Resources Information Center

Levin, Joseph; Brown, Morton

1979-01-01

Two least squares procedures for symmetrization of a conditional proximity matrix are derived. The solutions provide multiplicative constants for scaling the rows or columns of the matrix to maximize symmetry. (Author/JKS)

Skill-dependent proximal-to-distal sequence in team-handball throwing.

PubMed

Wagner, Herbert; Pfusterschmied, Jürgen; Von Duvillard, Serge P; Müller, Erich

2012-01-01

The importance of proximal-to-distal sequencing in human performance throwing has been reported previously. However, a comprehensive comparison of the proximal-to-distal sequence in team-handball throwing in athletes with different training experience and competition is lacking. Therefore, the aim of the study was to compare the ball velocity and proximal-to-distal sequence in the team-handball standing throw with run-up of players of different skill (less experienced, experienced, and elite). Twenty-four male team-handball players (n = 8 for each group) performed five standing throws with run-up with maximal ball velocity and accuracy. Kinematics and ball trajectories were recorded with a Vicon motion capture system and joint movements were calculated. A specific proximal-to-distal sequence, where elbow flexion occurred before shoulder internal rotation, was found in all three groups. These results are in line with previous studies in team-handball. Furthermore, the results of the present study suggest that in the team-handball standing throw with run-up, increased playing experience is associated with an increase in ball velocity as well as a delayed start to trunk flexion.

Spin-orbit proximity effect in graphene

NASA Astrophysics Data System (ADS)

Avsar, A.; Tan, J. Y.; Taychatanapat, T.; Balakrishnan, J.; Koon, G. K. W.; Yeo, Y.; Lahiri, J.; Carvalho, A.; Rodin, A. S.; O'Farrell, E. C. T.; Eda, G.; Castro Neto, A. H.; Özyilmaz, B.

2014-09-01

The development of spintronics devices relies on efficient generation of spin-polarized currents and their electric-field-controlled manipulation. While observation of exceptionally long spin relaxation lengths makes graphene an intriguing material for spintronics studies, electric field modulation of spin currents is almost impossible due to negligible intrinsic spin-orbit coupling of graphene. In this work, we create an artificial interface between monolayer graphene and few-layer semiconducting tungsten disulphide. In these devices, we observe that graphene acquires spin-orbit coupling up to 17 meV, three orders of magnitude higher than its intrinsic value, without modifying the structure of the graphene. The proximity spin-orbit coupling leads to the spin Hall effect even at room temperature, and opens the door to spin field effect transistors. We show that intrinsic defects in tungsten disulphide play an important role in this proximity effect and that graphene can act as a probe to detect defects in semiconducting surfaces.

Anatomic mapping for surgical reconstruction of the proximal tibiofibular ligaments.

PubMed

See, Aaron; Bear, Russell R; Owens, Brett D

2013-01-01

Injury to the proximal tibiofibular joint is uncommon. Previous studies regarding the anatomy of this region have predominantly focused on joint orientation. As radiographic technology has advanced, later studies have attempted to evaluate the capsular anatomy. However, no reports specifically map the ligaments to this joint. The objectives of the current study were to define specific ligamentous structures that provide stability to the proximal tibiofibular joint, describe easily identifiable and reproducible surgical landmarks to aid in surgical reconstruction, and add to the understanding of the posterolateral structures of the knee previously described by other authors. The proximal tibiofibular joint ligaments were identified in 10 fresh-frozen cadaveric specimens. Average ligament length, width, and thickness and area of the footprints of the tibial and fibular attachments were measured. Distances from the ligament footprints to known anatomic landmarks (eg, Gerdy's tubercle, tibial articular surface, and fibular styloid) were also measured. The anterior ligament tibial attachment was a mean of 15.6 mm lateral and posterior to Gerdy's tubercle and 17.3 mm anterior and inferior from the fibular styloid. Posterior ligament tibial insertion was a mean of 15.7 mm inferior to the tibial articular surface on the tibial side and 14.2 mm medial and slightly inferior from the fibular styloid. Definable ligaments provide stability to the proximal tibiofibular joint and can be reconstructed in an anatomic fashion using the landmarks and parameters described. This information allows for an anatomic reconstruction of the proximal tibiofibular joint, which should provide patients with better outcomes and fewer postoperative sequelae. Copyright 2013, SLACK Incorporated.

Biomechanical Strength of Retrograde Fixation in Proximal Third Scaphoid Fractures.

PubMed

Daly, Charles A; Boden, Allison L; Hutton, William C; Gottschalk, Michael B

2018-04-01

Current techniques for fixation of proximal pole scaphoid fractures utilize antegrade fixation via a dorsal approach endangering the delicate vascular supply of the dorsal scaphoid. Volar and dorsal approaches demonstrate equivalent clinical outcomes in scaphoid wrist fractures, but no study has evaluated the biomechanical strength for fractures of the proximal pole. This study compares biomechanical strength of antegrade and retrograde fixation for fractures of the proximal pole of the scaphoid. A simulated proximal pole scaphoid fracture was produced in 22 matched cadaveric scaphoids, which were then assigned randomly to either antegrade or retrograde fixation with a cannulated headless compression screw. Cyclic loading and load to failure testing were performed and screw length, number of cycles, and maximum load sustained were recorded. There were no significant differences in average screw length (25.5 mm vs 25.6 mm, P = .934), average number of cyclic loading cycles (3738 vs 3847, P = .552), average load to failure (348 N vs 371 N, P = .357), and number of catastrophic failures observed between the antegrade and retrograde fixation groups (3 in each). Practical equivalence between the 2 groups was calculated and the 2 groups were demonstrated to be practically equivalent (upper threshold P = .010). For this model of proximal pole scaphoid wrist fractures, antegrade and retrograde screw configuration have been proven to be equivalent in terms of biomechanical strength. With further clinical study, we hope surgeons will be able to make their decision for fixation technique based on approaches to bone grafting, concern for tenuous blood supply, and surgeon preference without fear of poor biomechanical properties.

Distributed Autonomous Control of Multiple Spacecraft During Close Proximity Operations

DTIC Science & Technology

2007-12-01

programs may be the XSS-11. The AFRL Space Vehicle Directorate at Kirtland Air Force Base in New Mexico developed the XSS-11 in order to exhibit the...the LQR/APF algorithm appears to be a promising new development for the field of multiple spacecraft close proximity maneuver control. Monte...dissertation reports the development of an autonomous distributed control algorithm for multiple spacecraft during close proximity operations

Mortality Following Periprosthetic Proximal Femoral Fractures Versus Native Hip Fractures.

PubMed

Boylan, Matthew R; Riesgo, Aldo M; Paulino, Carl B; Slover, James D; Zuckerman, Joseph D; Egol, Kenneth A

2018-04-04

The number of periprosthetic proximal femoral fractures is expected to increase with the increasing prevalence of hip arthroplasties. While native hip fractures have a well-known association with mortality, there are currently limited data on this outcome among the subset of patients with periprosthetic proximal femoral fractures. Using the New York Statewide Planning and Research Cooperative System, we identified patients from 60 to 99 years old who were admitted to a hospital in the state with a periprosthetic proximal femoral fracture (n = 1,655) or a native hip (femoral neck or intertrochanteric) fracture (n = 97,231) between 2006 and 2014. Within the periprosthetic fracture cohort, the indication for the existing implant was not available in the data set. We used mixed-effects regression models to compare mortality at 1 and 6 months and 1 year for periprosthetic compared with native hip fractures. The risk of mortality for patients who sustained a periprosthetic proximal femoral fracture was no different from that for patients who sustained a native hip fracture at 1 month after injury (3.2% versus 4.6%; odds ratio [OR], 0.90; 95% confidence interval [CI], 0.68 to 1.19; p = 0.446), but was lower at 6 months (3.8% versus 6.5%; OR, 0.74; 95% CI, 0.57 to 0.95; p = 0.020) and 1 year (9.7% versus 15.9%; OR, 0.71; 95% CI, 0.60 to 0.85; p < 0.001). Among periprosthetic proximal femoral fractures, factors associated with a significantly increased risk of mortality at 1 year included advanced age, male sex, and higher Deyo comorbidity scores. In the acute phase, any type of hip fracture appears to confer a similar risk of death. Over the long term, however, periprosthetic proximal femoral fractures are associated with lower mortality rates than native hip fractures, even after accounting for age and comorbidities. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Proximal junctional kyphosis following adult spinal deformity surgery.

PubMed

Cho, Samuel K; Shin, John I; Kim, Yongjung J

2014-12-01

Proximal junctional kyphosis (PJK) is a common radiographic finding following long spinal fusions. Whether PJK leads to negative clinical outcome is currently debatable. A systematic review was performed to assess the prevalence, risk factors, and treatments of PJK. Literature search was conducted on PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials using the terms 'proximal junctional kyphosis' and 'proximal junctional failure'. Excluding reviews, commentaries, and case reports, we analyzed 33 studies that reported the prevalence rate, risk factors, and discussions on PJK following spinal deformity surgery. The prevalence rates varied widely from 6 to 61.7%. Numerous studies reported that clinical outcomes for patients with PJK were not significantly different from those without, except in one recent study in which adult patients with PJK experienced more pain. Risk factors for PJK included age at operation, low bone mineral density, shorter fusion constructs, upper instrumented vertebrae below L2, and inadequate restoration of global sagittal balance. Prevalence of PJK following long spinal fusion for adult spinal deformity was high but not clinically significant. Careful and detailed preoperative planning and surgical execution may reduce PJK in adult spinal deformity patients.

Evolution and proximate expression of human paternal investment.

PubMed

Geary, D C

2000-01-01

In more than 95% of mammalian species, males provide little direct investment in the well-being of their offspring. Humans are one notable exception to this pattern and, to date, the factors that contributed to the evolution and the proximate expression of human paternal care are unexplained (T. H. Clutton-Brock, 1989). The nature, extent, and influence of human paternal investment on the physical and social well-being of children are reviewed in light of the social and ecological factors that are associated with paternal investment in other species. On the basis of this review, discussion of the evolution and proximate expression of human paternal investment is provided.

Ectrodactyly and proximal/intermediate interstitial deletion 7q

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.

Close Encounters - Probing Proximal Proteins in Live or Fixed Cells.

PubMed

Lönn, Peter; Landegren, Ulf

2017-07-01

The well-oiled machinery of the cellular proteome operates via variable expression, modifications, and interactions of proteins, relaying genomic and transcriptomic information to coordinate cellular functions. In recent years, a number of techniques have emerged that serve to identify sets of proteins acting in close proximity in the course of orchestrating cellular activities. These proximity-dependent assays, including BiFC, BioID, APEX, FRET, and isPLA, have opened up new avenues to examine protein interactions in live or fixed cells. We review herein the current status of proximity-dependent in situ techniques. We compare the advantages and limitations of the methods, underlining recent progress and the growing importance of these techniques in basic research, and we discuss their potential as tools for drug development and diagnostics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bringing Proximate Neighbours into the Study of US Residential Segregation

PubMed Central

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. PMID:21544258

Magnetic ground state of the layered honeycomb compound Na2Co2TeO6

NASA Astrophysics Data System (ADS)

Bera, A. K.; Yusuf, S. M.

2018-04-01

The magnetic correlations in the 2D layered honeycomb compound Na2Co2TeO6 has been investigated. The temperature dependent susceptibility curve reveals a transition to the magnetically ordered state at TN ˜ 25 K. The temperature dependent neutron diffraction study confirms an antiferromagnetic ordering below TN. The magnetic ground state is determined to be a zigzag antiferromagnet that appears due to competing exchange interactions beyond nearest neighbors. The moments align along the crystallographic b axis with reduced ordered magnetic moment values of 2.72(2) μB/Co2+ and 2.52(3) μB/Co2+ for two Co sites, respectively. In comparison to the theoretical phase diagram the determined zigzag antiferromagnetic ground state suggests that the compound Na2Co2TeO6 is situated in the proximity to the quantum spin liquid state in the phase diagram.

Quaternary structure and apical membrane sorting of the mammalian NaSi-1 sulfate transporter in renal cell lines.

PubMed

Regeer, Ralf R; Nicke, Annette; Markovich, Daniel

2007-01-01

NaSi-1 encodes a Na(+)-sulfate cotransporter expressed on the apical membrane of renal proximal tubular cells, which is responsible for body sulfate homeostasis. Limited information is available on NaSi-1 protein structure and the mechanisms controlling its apical membrane sorting. The aims of this study were to biochemically determine the quaternary structure of the rat NaSi-1 protein and to characterize its expression in renal epithelial cell lines. Hexahistidyl-tagged NaSi-1 (NaSi-1-His) proteins expressed in Xenopus oocytes, appeared as two bands of about 60 and 75 kDa. PNGase F treatment shifted both bands to 57 kDa while endoglycosidase H treatment led to a downward shift of the lower molecular mass band only. Mutagenesis of a putative N-glycosylation site (N591S) produced a single band that was not shifted by endoglycosidase H or PNGase F, confirming a single glycosylation site at residue 591. Blue native-PAGE and cross-linking experiments revealed dimeric complexes, suggesting the native form of NaSi-1 to be a dimer. Transient transfection of EGFP/NaSi-1 in renal epithelial cells (OK, LLC-PK1 and MDCK) demonstrated apical membrane sorting, which was insensitive to tunicamycin. Transfection of the EGFP/NaSi-1 N591S glycosylation mutant also showed apical expression, suggesting N591 is not essential for apical sorting. Treatment with cholesterol depleting compounds did not disrupt apical sorting, but brefeldin A led to misrouting to the basolateral membrane, suggesting that NaSi-1 sorting is through the ER to Golgi pathway. Our data demonstrates that NaSi-1 forms a dimeric protein which is glycosylated at N591, whose sorting to the apical membrane in renal epithelial cells is brefeldin A-sensitive and independent of lipid rafts or glycosylation.

Theory of electronic and spin-orbit proximity effects in graphene on Cu(111)

NASA Astrophysics Data System (ADS)

Frank, Tobias; Gmitra, Martin; Fabian, Jaroslav

2016-04-01

We study orbital and spin-orbit proximity effects in graphene adsorbed to the Cu(111) surface by means of density functional theory (DFT). The proximity effects are caused mainly by the hybridization of graphene π and copper d orbitals. Our electronic structure calculations agree well with the experimentally observed features. We carry out a graphene-Cu(111) distance dependent study to obtain proximity orbital and spin-orbit coupling parameters, by fitting the DFT results to a robust low energy model Hamiltonian. We find a strong distance dependence of the Rashba and intrinsic proximity induced spin-orbit coupling parameters, which are in the meV and hundreds of μ eV range, respectively, for experimentally relevant distances. The Dirac spectrum of graphene also exhibits a proximity orbital gap, of about 20 meV. Furthermore, we find a band inversion within the graphene states accompanied by a reordering of spin and pseudospin states, when graphene is pressed towards copper.

Wild-type APC predicts poor prognosis in microsatellite-stable proximal colon cancer.

PubMed

Jorissen, Robert N; Christie, Michael; Mouradov, Dmitri; Sakthianandeswaren, Anuratha; Li, Shan; Love, Christopher; Xu, Zheng-Zhou; Molloy, Peter L; Jones, Ian T; McLaughlin, Stephen; Ward, Robyn L; Hawkins, Nicholas J; Ruszkiewicz, Andrew R; Moore, James; Burgess, Antony W; Busam, Dana; Zhao, Qi; Strausberg, Robert L; Lipton, Lara; Desai, Jayesh; Gibbs, Peter; Sieber, Oliver M

2015-09-15

APC mutations (APC-mt) occur in ∼70% of colorectal cancers (CRCs), but their relationship to prognosis is unclear. APC prognostic value was evaluated in 746 stage I-IV CRC patients, stratifying for tumour location and microsatellite instability (MSI). Microarrays were used to identify a gene signature that could classify APC mutation status, and classifier ability to predict prognosis was examined in an independent cohort. Wild-type APC microsatellite stable (APC-wt/MSS) tumours from the proximal colon showed poorer overall and recurrence-free survival (OS, RFS) than APC-mt/MSS proximal, APC-wt/MSS distal and APC-mt/MSS distal tumours (OS HR⩾1.79, P⩽0.015; RFS HR⩾1.88, P⩽0.026). APC was a stronger prognostic indicator than BRAF, KRAS, PIK3CA, TP53, CpG island methylator phenotype or chromosomal instability status (P⩽0.036). Microarray analysis similarly revealed poorer survival in MSS proximal cancers with an APC-wt-like signature (P=0.019). APC status did not affect outcomes in MSI tumours. In a validation on 206 patients with proximal colon cancer, APC-wt-like signature MSS cases showed poorer survival than APC-mt-like signature MSS or MSI cases (OS HR⩾2.50, P⩽0.010; RFS HR⩾2.14, P⩽0.025). Poor prognosis APC-wt/MSS proximal tumours exhibited features of the sessile serrated neoplasia pathway (P⩽0.016). APC-wt status is a marker of poor prognosis in MSS proximal colon cancer.

Recreation in urban-proximate natural areas

Treesearch

P.L. Winter; D.J. Chavez

1999-01-01

Recreation in urban proximate wildland and wilderness areas and resulting management concerns and challenges have proven a fertile ground for social science research. As the demand for recreation opportunities adjacent to large urban centers has increased, so has the variety of recreational interests, patterns, and preferences, a reflection of the diverse...

Ultrasonographic assessment of the proximal digital annular ligament in the equine forelimb.

PubMed

Dik, K J; Boroffka, S; Stolk, P

1994-01-01

Ultrasonography was used with 6 normal cadaver forelimbs of Dutch Warmblood horses to delineate the ultrasonographic anatomy of the palmar pastern region, with emphasis on the proximal digital annular ligament. Using a 5.5 MHz sector scanner, the thin proximal digital annular ligament was not visible on offset sonograms. Only if the digital sheath in the normal limb was distended was the distal border of this ligament outlined. In all normal limbs the palmarodistal thickness of the combined skin-proximal digital annular ligament layer in the mid-pastern region was 2 mm. The flexor tendons and distal sesamoidean ligaments were easily identified as hyperechoic structures. Distension of the digital sheath in the normal limbs clearly outlined the anechoic digital sheath pouches. In 4 lame horses ultrasonography aided the diagnosis of functional proximal digital annular ligament constriction. In all 4 diseased forelimbs ultrasonography demonstrated thickening of the skin-proximal digital annular ligament layer and distension of the digital sheath. In one of these limbs the distended digital sheath was also thickened. The flexor tendons and distal sesamoidean ligaments were normal. There was no radiographic evidence of additional bone or joint lesions.

Uptake of leptin and albumin via separate pathways in proximal tubule cells.

PubMed

Briffa, Jessica F; Grinfeld, Esther; Poronnik, Philip; McAinch, Andrew J; Hryciw, Deanne H

2016-10-01

The adipokine leptin and oncotic protein albumin are endocytosed in the proximal tubule via the scavenger receptor megalin. Leptin reduces megalin expression and activates cell signalling pathways that upregulate fibrotic protein expression. The aim of this study was to investigate if leptin uptake in proximal tubule cells was via the albumin-megalin endocytic complex. In immortalised proximal tubule Opossum kidney cells (OK) fluorescent leptin and albumin co-localised following 5min exposure, however there was no co-localisation at 10, 20 and 30min exposure. In OK cells, acute exposure to leptin for 2h did not alter NHE3, ClC-5, NHERF1 and NHERF2 mRNA. However, acute leptin exposure increased NHERF2 protein expression in proximal tubule cells. In OK cells, immunoprecipitation experimentation indicated leptin did not bind to ClC-5. Leptin uptake in OK cells was enhanced by bafilomycin and ammonium chloride treatment, demonstrating that uptake was not dependent on lysosomal pH. Thus, it is likely that two pools of megalin exist in proximal tubule cells to facilitate separate uptake of leptin and albumin by endocytosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

N-domain angiotensin-I converting enzyme is expressed in immortalized mesangial, proximal tubule and collecting duct cells.

PubMed

Mei Wang, Pamella Huey; Andrade, Maria Claudina; Quinto, Beata Marie Redublo; Di Marco, Giovana; Mortara, Renato Arruda; Vio, Carlos P; Casarini, Dulce Elena

2015-01-01

Somatic ACE (sACE) is found in glomerulus, proximal tubule and excreted in urine. We hypothesized that N-domain ACE can also be found at these sites. ACE profile was analyzed in mesangial (IMC), proximal (LLC-PK1), distal tubule (MDCK) and collecting duct (IMCD) cells. Cell lysate and culture medium were submitted to gel filtration chromatography, which separated two peaks with ACE activity from cells and medium, except from distal tubule. The first had a high molecular weight and the second, a lower one (65 kDa; N-domain ACE). We focused on N-domain ACE purification and characterization from LLC-PK1. Total LLC-PK1 N-domain ACE purification was achieved by ion-exchange chromatography, which presented only one peak with ACE activity, denominated ACE(int2A). ACE(int2A) activity was influenced by pH, NaCl and temperature. The purified enzyme was inhibited by Captopril and hydrolyzed AngI, Ang1-7 and AcSDKP. Its ability to hydrolyze AcSDKP characterized it as an N-domain ACE. ACE(int2A) also presented high amino acid sequence homology with the N-terminal part of sACE from mouse, rat, human and rabbit. The presence of secreted and intracellular N-domain ACE and sACE in IMC, LLC-PK1 and IMCD cells confirmed our studies along the nephron. We identified, purified and characterized N-domain ACE from LLC-PK1. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

Hydrogen sulfide inhibits high glucose-induced NADPH oxidase 4 expression and matrix increase by recruiting inducible nitric oxide synthase in kidney proximal tubular epithelial cells.

PubMed

Lee, Hak Joo; Lee, Doug Yoon; Mariappan, Meenalakshmi M; Feliers, Denis; Ghosh-Choudhury, Goutam; Abboud, Hanna E; Gorin, Yves; Kasinath, Balakuntalam S

2017-04-07

High-glucose increases NADPH oxidase 4 (NOX4) expression, reactive oxygen species generation, and matrix protein synthesis by inhibiting AMP-activated protein kinase (AMPK) in renal cells. Because hydrogen sulfide (H 2 S) inhibits high glucose-induced matrix protein increase by activating AMPK in renal cells, we examined whether H 2 S inhibits high glucose-induced expression of NOX4 and matrix protein and whether H 2 S and NO pathways are integrated. High glucose increased NOX4 expression and activity at 24 h in renal proximal tubular epithelial cells, which was inhibited by sodium hydrosulfide (NaHS), a source of H 2 S. High glucose decreased AMPK phosphorylation and activity, which was restored by NaHS. Compound C, an AMPK inhibitor, prevented NaHS inhibition of high glucose-induced NOX4 expression. NaHS inhibition of high glucose-induced NOX4 expression was abrogated by N (ω)-nitro-l-arginine methyl ester, an inhibitor of NOS. NaHS unexpectedly augmented the expression of inducible NOS (iNOS) but not endothelial NOS. iNOS siRNA and 1400W, a selective iNOS inhibitor, abolished the ameliorative effects of NaHS on high glucose-induced NOX4 expression, reactive oxygen species generation, and, matrix laminin expression. Thus, H 2 S recruits iNOS to generate NO to inhibit high glucose-induced NOX4 expression, oxidative stress, and matrix protein accumulation in renal epithelial cells; the two gasotransmitters H 2 S and NO and their interaction may serve as therapeutic targets in diabetic kidney disease. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Evaluation of a proximity card authentication system for health care settings.

PubMed

Fontaine, Jacqueline; Zheng, Kai; Van De Ven, Cosmas; Li, Huiyang; Hiner, James; Mitchell, Kathy; Gendler, Stephen; Hanauer, David A

2016-08-01

Multiple users access computer workstations in busy clinical settings, requiring many logins throughout the day as users switch from one computer to another. This can lead to workflow inefficiencies as well as security concerns resulting from users sharing login sessions to save time. Proximity cards and readers have the potential to improve efficiency and security by allowing users to access clinical workstations simply by bringing the card near the reader, without the need for manual entry of a username and password. To assess the perceived impact of proximity cards and readers for rapid user authentication to clinical workstations in the setting of an existing electronic health record with single sign-on software already installed. Questionnaires were administered to clinical faculty and staff five months before and three months after the installation of proximity card readers in an inpatient birthing center and an outpatient obstetrics clinic. Open-ended feedback was also collected and qualitatively analyzed. There were 71 and 33 responses to the pre- and post-implementation surveys, respectively. There was a significant increase in the perceived speed of login with the proximity cards, and a significant decrease in the self-reported occurrence of shared login sessions between users. Feedback regarding the system was mostly positive, although several caveats were noted, including minimal benefit when used with an obstetric application that did not support single sign-on. Proximity cards and readers, along with single sign-on software, have the potential to enhance workflow efficiency by allowing for faster login times and diminish security concerns by reducing shared logins on clinical workstations. The positive feedback was used by our health system leadership to support the expanded implementation of the proximity card readers throughout the clinical setting. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Proximal femoral osteosarcoma: Diagnostic challenges translate into delayed and inappropriate management.

PubMed

Dahan, M; Anract, P; Babinet, A; Larousserie, F; Biau, D

2017-11-01

The proximal femuris is an uncommon site of osteosarcoma. The unusual manifestations at this site may lead to diagnostic and therapeutic mistakes. We therefore performed a retrospective study to estimate the proportions of patients with imaging study findings and/or clinical manifestations typical for osteosarcoma and/or inappropriate treatment decisions. Proximal femoral osteosarcoma often produces atypical clinical and radiological presentations. Consecutive patients who underwent surgery at our center to treat proximal femoral osteosarcoma were included. For each patient, we collected the epidemiological characteristics, clinical symptoms, imaging study findings, treatment, and tumor outcome. Proportions were computed with their confidence intervals. Twelve patients had surgery for proximal femoral osteosarcoma between 1986 and 2015. Imaging findings were typical in 1 (8%) patient; they consisted of ill-defined osteolysis in 11/12 (92%) patients, a periosteal reaction in 1/12 (8%) patient, soft tissue involvement in 7/12 (58%) patients, and immature osteoid matrix in 11/12 (92%) patients. No patient had the typical combination of pain with a soft tissue swelling. Management was inappropriate in 2/12 (17%) patients, who did not undergo all the recommended imaging studies before surgery and were treated in another center before the correct diagnosis was established. At last follow-up, 4 patients had died (after a mean of 7 years) and 8 were alive (after a mean of 4 years). Proximal femoral osteosarcoma is uncommon and rarely produces the typical clinical and imaging study findings. The atypical presentation often results in diagnostic errors and inappropriate treatments. Ill-defined osteolysis on standard radiographs should prompt computed tomography or magnetic resonance imaging of the proximal femur. Treatment in a specialized center is imperative. IV, retrospective study. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Proximity-induced superconductivity in crystalline Cu and Co nanowires and nanogranular Co structures

NASA Astrophysics Data System (ADS)

Kompaniiets, M.; Dobrovolskiy, O. V.; Neetzel, C.; Begun, E.; Porrati, F.; Ensinger, W.; Huth, M.

2014-08-01

We report an experimental study of proximity effect-induced superconductivity in crystalline Cu and Co nanowires and a nanogranular Co nanowire structure in contact with a superconducting W-based floating electrode (inducer). For electrical resistance measurements up to three pairs of Pt-based voltage leads were attached at different distances beside the inner inducer electrode, thus allowing us to probe the proximity effect over a length of 2-12 μm. Up to 30% resistance drops with respect to the normal-state value have been observed for the crystalline Co and Cu nanowires when sweeping the temperature below Tc of the inducer (5.2 K). By contrast, relative R(T) drops were found to be an order of magnitude smaller for the nanogranular Co nanowire structure. Our analysis of the resistance data shows that the superconducting proximity length in crystalline Cu and Co is about 1 μm at 2.4 K, attesting to a long-range proximity effect in the Co nanowire. Moreover, this long-range proximity effect is insusceptible to magnetic fields up to 11 T, which is indicative of spin-triplet pairing. At the same time, proximity-induced superconductivity in the nanogranular Co nanowire is strongly suppressed due to the dominating Cooper pair scattering caused by its intrinsic microstructure.

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.

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.

Activation of D4 dopamine receptor decreases AT1 angiotensin II receptor expression in rat renal proximal tubule cells

PubMed Central

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

2014-01-01

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

Proximal dentatothalamocortical tract involvement in posterior fossa syndrome

PubMed Central

Phillips, Nicholas S.; Laningham, Fred H.; Patay, Zoltan; Gajjar, Amar; Wallace, Dana; Boop, Frederick; Sanford, Robert; Ness, Kirsten K.; Ogg, Robert J.

2009-01-01

Posterior fossa syndrome is characterized by cerebellar dysfunction, oromotor/oculomotor apraxia, emotional lability and mutism in patients after infratentorial injury. The underlying neuroanatomical substrates of posterior fossa syndrome are unknown, but dentatothalamocortical tracts have been implicated. We used pre- and postoperative neuroimaging to investigate proximal dentatothalamocortical tract involvement in childhood embryonal brain tumour patients who developed posterior fossa syndrome following tumour resection. Diagnostic imaging from a cohort of 26 paediatric patients previously operated on for an embryonal brain tumour (13 patients prospectively diagnosed with posterior fossa syndrome, and 13 non-affected patients) were evaluated. Preoperative magnetic resonance imaging was used to define relevant tumour features, including two potentially predictive measures. Postoperative magnetic resonance and diffusion tensor imaging were used to characterize operative injury and tract-based differences in anisotropy of water diffusion. In patients who developed posterior fossa syndrome, initial tumour resided higher in the 4th ventricle (P = 0.035). Postoperative magnetic resonance signal abnormalities within the superior cerebellar peduncles and midbrain were observed more often in patients with posterior fossa syndrome (P = 0.030 and 0.003, respectively). The fractional anisotropy of water was lower in the bilateral superior cerebellar peduncles, in the bilateral fornices, white matter region proximate to the right angular gyrus (Tailerach coordinates 35, –71, 19) and white matter region proximate to the left superior frontal gyrus (Tailerach coordinates –24, 57, 20). Our findings suggest that multiple bilateral injuries to the proximal dentatothalamocortical pathways may predispose the development of posterior fossa syndrome, that functional disruption of the white matter bundles containing efferent axons within the superior cerebellar peduncles is a

Electromagnetic Signal Feedback Control for Proximity Detection Systems

NASA Astrophysics Data System (ADS)

Smith, Adam K.

Coal is the most abundant fossil fuel in the United States and remains an essential source of energy. While more than half of coal production comes from surface mining, nearly twice as many workers are employed by underground operations. One of the key pieces of equipment used in underground coal mining is the continuous mining machine. These large and powerful machines are operated in confined spaces by remote control. Since 1984, 40 mine workers in the U. S. have been killed when struck or pinned by a continuous mining machine. It is estimated that a majority of these accidents could have been prevented with the application of proximity detection systems. While proximity detection systems can significantly increase safety around a continuous mining machine, there are some system limitations. Commercially available proximity warning systems for continuous mining machines use magnetic field generators to detect workers and establish safe work areas around the machines. Several environmental factors, however, can influence and distort the magnetic fields. To minimize these effects, a control system has been developed using electromagnetic field strength and generator current to stabilize and control field drift induced by internal and external environmental factors. A laboratory test set-up was built using a ferrite-core magnetic field generator to produce a stable magnetic field. Previous work based on a field-invariant magnetic flux density model, which generically describes the electromagnetic field, is expanded upon. The analytically established transferable shell-based flux density distribution model is used to experimentally validate the control system. By controlling the current input to the ferrite-core generator, a more reliable and consistent magnetic field is produced. Implementation of this technology will improve accuracy and performance of existing commercial proximity detection systems. These research results will help reduce the risk of traumatic

Enhanced proximity warning system (EPWS) for locomotives

DOT National Transportation Integrated Search

1997-10-01

The primary focus of the Enhanced Proximity Warning System (EPWS) is to provide a cost effective means to improve safety of railroad operations, with the ability to implement on an incremental, building block approach. The main safety objective...

Proximal hamstring reconstruction using semitendinosus and gracilis autograft: a novel technique.

PubMed

Muellner, Thomas; Kumar, Sandeep; Singla, Amit

2017-01-01

The complete proximal hamstring avulsion is relatively uncommon injury and predominantly occurs in young athletes but causes significant functional impairment. In chronic cases, the muscle mass is so much retracted that primary repair is not possible. A surgical technique for reconstruction of chronic proximal hamstring avulsion using contralateral semitendinosus and gracilis autograft is described in this case report. V.

[Pathologic proximal femoral fractures in children in an unicameral bone cyst].

PubMed

Havránek, P; Pesl, T; Bartonícek, J

2005-01-01

Proximal femoral fractures in children are rare, pathologic fractures being extremely rare. Despite many meanings these fractures are still "unsolved" there are some definite rules for treatment of true accidental injuries. Pathologic fractures are outstanding with their extremely rare incidence. The aim of the study is to overview a large clinical material, find out the incidence of this pathologic fracture, the extent and shape of the unicameral bone cyst (UBC), specific therapeutic approach, technical problems of eventual osteosynthesis, number of reoperations and sequels. Altogether 49 children with 50 accidental and pathologic fractures of proximal part of the femur treated in the Regional Pediatric Trauma Centre of the Department of Pediatric and Trauma Surgery, 3rd Faculty of Medicine, Charles University, Prague. Retrospective and prospective study of children (0 to 15 years of age) treated with proximal femoral accidental and pathologic fractures during the 20 year period (from August 1984 to November 2004). Classification of fractures according to Delbet and Colonna. Diagnosis of bone cyst with plain X-rays, eventually CT scans. During the 20 years period (August 1984 to November 2004) 49 children with 50 proximal femoral fractures were treated in the Department. Four patients sustained a pathologic fracture through an unicameral bone cyst. Two of these latter children were treated by an open reduction and osteosynthesis with the use of the proximal femoral AO-ASIF angled-plate and two children nonoperatively using skeletal traction because of impossibility of insertion of the osteosynthetic material without a damage of the growth plate. Subsequent operations of the UBC were necessary in these two children. All four patients recovered well without sequels. Pathologic fractures in UBC are usually treated nonoperatively and the cyst itself is treated after fracture healing. Proximal femoral impairment is the exception from this rule because of weigh bearing

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

PubMed

Sackin, H; Boulpaep, E L

1975-12-01

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

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

PubMed Central

Sackin, H; Boulpaep, EL

1975-01-01

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

A scoping review of biomechanical testing for proximal humerus fracture implants.

PubMed

Cruickshank, David; Lefaivre, Kelly A; Johal, Herman; MacIntyre, Norma J; Sprague, Sheila A; Scott, Taryn; Guy, Pierre; Cripton, Peter A; McKee, Michael; Bhandari, Mohit; Slobogean, Gerard P

2015-07-30

Fixation failure is a relatively common sequela of surgical management of proximal humerus fractures (PHF). The purpose of this study is to understand the current state of the literature with regard to the biomechanical testing of proximal humerus fracture implants. A scoping review of the proximal humerus fracture literature was performed, and studies testing the mechanical properties of a PHF treatment were included in this review. Descriptive statistics were used to summarize the characteristics and methods of the included studies. 1,051 proximal humerus fracture studies were reviewed; 67 studies met our inclusion criteria. The most common specimen used was cadaver bone (87%), followed by sawbones (7%) and animal bones (4%). A two-part fracture pattern was tested most frequently (68%), followed by three-part (23%), and four-part (8%). Implants tested included locking plates (52%), intramedullary devices (25%), and non-locking plates (25%). Hemi-arthroplasty was tested in 5 studies (7%), with no studies using reverse total shoulder arthroplasty (RTSA) implants. Torque was the most common mode of force applied (51%), followed by axial loading (45%), and cantilever bending (34%). Substantial testing diversity was observed across all studies. The biomechanical literature was found to be both diverse and heterogeneous. More complex fracture patterns and RTSA implants have not been adequately tested. These gaps in the current literature will need to be addressed to ensure that future biomechanical research is clinically relevant and capable of improving the outcomes of challenging proximal humerus fracture patterns.

Proximal sensing for soil carbon accounting

NASA Astrophysics Data System (ADS)

England, Jacqueline R.; Viscarra Rossel, Raphael A.

2018-05-01

Maintaining or increasing soil organic carbon (C) is vital for securing food production and for mitigating greenhouse gas (GHG) emissions, climate change, and land degradation. Some land management practices in cropping, grazing, horticultural, and mixed farming systems can be used to increase organic C in soil, but to assess their effectiveness, we need accurate and cost-efficient methods for measuring and monitoring the change. To determine the stock of organic C in soil, one requires measurements of soil organic C concentration, bulk density, and gravel content, but using conventional laboratory-based analytical methods is expensive. Our aim here is to review the current state of proximal sensing for the development of new soil C accounting methods for emissions reporting and in emissions reduction schemes. We evaluated sensing techniques in terms of their rapidity, cost, accuracy, safety, readiness, and their state of development. The most suitable method for measuring soil organic C concentrations appears to be visible-near-infrared (vis-NIR) spectroscopy and, for bulk density, active gamma-ray attenuation. Sensors for measuring gravel have not been developed, but an interim solution with rapid wet sieving and automated measurement appears useful. Field-deployable, multi-sensor systems are needed for cost-efficient soil C accounting. Proximal sensing can be used for soil organic C accounting, but the methods need to be standardized and procedural guidelines need to be developed to ensure proficient measurement and accurate reporting and verification. These are particularly important if the schemes use financial incentives for landholders to adopt management practices to sequester soil organic C. We list and discuss requirements for developing new soil C accounting methods based on proximal sensing, including requirements for recording, verification, and auditing.

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.

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.

Fatigue fracture of a proximally modular, distally tapered fluted implant with diaphyseal fixation.

PubMed

Buttaro, Martín A; Mayor, Michael B; Van Citters, Douglas; Piccaluga, Francisco

2007-08-01

We report and analyze the causes of a fracture in a proximally modular, distally tapered fluted MP stem in a 48-year-old woman (168 cm, 67 kg) with severe proximal bone deficiency. Evidence of fatigue failure with striations initiated laterally was observed in the laser etching of the tensile aspect of the prosthesis. However, metallurgical analysis suggested that laser engraving did not alter the microstructure of the stem. Stress due to the absence of proximal femoral bone support may have been sufficiently high to put this particular stem at risk for fatigue fracture. This important complication should be addressed when choosing this therapeutic option in cases with substantial proximal femoral bone loss. Strut allograft support should be recommended in such cases.

The Zone of Proximal "Teacher" Development

ERIC Educational Resources Information Center

Warford, Mark K.

2011-01-01

Toward the end of his short life, Lev Vygotsky found himself teaching teachers in a remote part of the USSR. Though his influence as a developmental psychologist is well-established, little is known about his approach to teacher development. This article applies the researcher's core concept, the zone of proximal development to teacher education.…

Impaired organic ion transport in proximal tubules of rats with Heymann nephritis.

PubMed

Park, E K; Hong, S K; Goldinger, J; Andres, G; Noble, B

1985-10-01

Organic ion transport across the basolateral membrane of proximal tubules was measured by means of the tissue slice technique in each of the four different stages of Heymann nephritis. Impairment of both organic anion and cation transport was detected early in Stage 2, and became more severe in Stage 3 of Heymann nephritis. The decreased transport function was associated with extensive damage to proximal tubule cells, including loss of brush border microvilli and basal infoldings. Despite these abnormalities of structure and function, oxygen consumption of proximal tubule cells remained essentially normal. Partial recovery of organic cation transport was noted late in Heymann nephritis (Stage 4). Recovery of the cation transport function was associated with a partial restoration of brush border microvilli and basal infoldings to proximal tubule cells. However, organic anion transport remained depressed throughout the entire course of disease. Impairment of organic ion transport in rats with Heymann nephritis appeared to result from damage to basolateral membrane transport elements rather than general deterioration of the metabolic machinery of proximal tubule cells. Decreased organic cation transport appeared to be the consequence of a reduction in the number of carrier sites, a phenomenon that could have resulted from decreased membrane surface area. However, the depression of organic anion transport was associated with decreased substrate affinity of the anion carrier, indicating that qualitative, rather than quantitative changes, were primarily responsible for that defect. Specific antibody-mediated damage to the anion transport elements in basolateral membranes of proximal tubules is postulated to occur in Heymann nephritis.

Elevated oxidized glutathione in cystinotic proximal tubular epithelial cells.

PubMed

Wilmer, Martijn J G; de Graaf-Hess, Adriana; Blom, Henk J; Dijkman, Henry B P M; Monnens, Leo A; van den Heuvel, Lambertus P; Levtchenko, Elena N

2005-11-18

Cystinosis, the most frequent cause of inborn Fanconi syndrome, is characterized by the lysosomal cystine accumulation, caused by mutations in the CTNS gene. To elucidate the pathogenesis of cystinosis, we cultured proximal tubular cells from urine of cystinotic patients (n = 9) and healthy controls (n = 9), followed by immortalization with human papilloma virus (HPV E6/E7). Obtained cell lines displayed basolateral polarization, alkaline phosphatase activity, and presence of aminopeptidase N (CD-13) and megalin, confirming their proximal tubular origin. Cystinotic cell lines exhibited elevated cystine levels (0.86 +/- 0.95 nmol/mg versus 0.09 +/- 0.01 nmol/mg protein in controls, p = 0.03). Oxidized glutathione was elevated in cystinotic cells (1.16 +/- 0.83 nmol/mg versus 0.29 +/- 0.18 nmol/mg protein, p = 0.04), while total glutathione, free cysteine, and ATP contents were normal in these cells. In conclusion, elevated oxidized glutathione in cystinotic proximal tubular epithelial cell lines suggests increased oxidative stress, which may contribute to tubular dysfunction in cystinosis.

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

Close proximity electrostatic effect from small clusters of emitters

NASA Astrophysics Data System (ADS)

Dall'Agnol, Fernando F.; de Assis, Thiago A.

2017-10-01

Using a numerical simulation based on the finite-element technique, this work investigates the field emission properties from clusters of a few emitters at close proximity, by analyzing the properties of the maximum local field enhancement factor (γm ) and the corresponding emission current. At short distances between the emitters, we show the existence of a nonintuitive behavior, which consists of the increasing of γm as the distance c between the emitters decreases. Here we investigate this phenomenon for clusters with 2, 3, 4 and 7 identical emitters and study the influence of the proximity effect in the emission current, considering the role of the aspect ratio of the individual emitters. Importantly, our results show that peripheral emitters with high aspect-ratios in large clusters can, in principle, significantly increase the emitted current as a consequence only of the close proximity electrostatic effect (CPEE). This phenomenon can be seen as a physical mechanism to produce self-oscillations of individual emitters. We discuss new insights for understanding the nature of self-oscillations in emitters based on the CPEE, including applications to nanometric oscillators.

Na+-coupled bicarbonate transporters in duodenum, collecting ducts and choroid plexus.

PubMed

Praetorius, Jeppe

2010-01-01

Epithelia cover the internal and external surfaces of the organism and form barriers between the various compartments. Some of these epithelia are specialized for effective transmembrane or even transepithelial movement of acid-base equivalents. Certain epithelia with a high rate of HCO3- transport express a few potent Na+-coupled acid-base transporters to gain a net HCO3- movement across the epithelium. Examples of such epithelia are renal proximal tubules and pancreatic ducts. In contrast, multiple Na+-coupled HCO3- transporters are expressed in other HCO3- secreting epithelia, such as the duodenal mucosa or the choroid plexus, which maintain suitable intracellular pH despite a variable demand for secreting HCO3-. In the duodenum, the epithelial cells must secrete HCO3- for neutralization of the gastric acid, and at the same time prevent cellular acidification. During the neutralization, large quantities of CO2 are formed in the duodenal lumen, which enter the epithelial cells. This would tend to lower intracellular pH and require effective counteracting mechanisms to avoid cell death and to maintain HCO3- secretion. The choroid plexus secretes the cerebrospinal fluid (CSF) and controls the pH of the otherwise poorly buffered CSF. The pCO2 of CSF fluctuates with plasma pCO2, and the choroid plexus must regulate the HCO3- secretion to minimize the effects of these fluctuations on CSF pH. This is done while maintaining pH neutrality in the epithelial cells. Thus, the Na+-HCO3- cotransporters appear to be involved in HCO3- import in more epithelia, where Na+/H+ exchangers were until recently thought to be sufficient for maintaining intracellular pH.

Tubularized proximally-incised plate in distal/midshaft hypospadias repair.

PubMed

Marte, Antonio; Pintozzi, Lucia

2017-06-23

The aim of this study was to verify the validity, feasibility, and the functional results, by uroflowmetry, of Tubularized proximallyincised plate technique in selected case of distal/midshaft hypospadias. Out of 120 patients scheduled to undergo TIP (or Snodgrass) procedure, 23 were selected between January 2013 and January 2016 (19.1%). This case series comprised 16 patients with distal and 7 with midshaft hypospadias. Mean age at surgery was 2.9 years. The inclusion criteria were a deep and wide glandular groove and a proximal narrow urethral plate. The procedure was carried out as described by Snodgrass but the incision of the urethral plate, including the mucosal and submucosal tissue, was made only proximally, between the original meatus and the glandular groove in no case extending to the entire length of the plate. Postoperatively a foley catheter was left in place from 4 to 7 days. Uroflowmetry was performed when the patients age ranged from 2.5 to 5.7 years (mean age 3.11 years and mean follow-up 1.8 years, body surface 2). No patient presented fistulas nor perioperative complications. At uroflowmetry, eighteen patients presented values above the 25th percentile and 5 showed a borderline flow. All patients in this group remained stable without urinary symptoms. In selected cases, the tubularized proximally-incised plate yields satisfactory cosmetic and functional results for the treatment of midshaft proximal hypospadias. A long-term follow-up study is needed for further evaluation. Patient selection is crucial for the success of this technique.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barritt, J.A.; Teague, K.E.; Bodurtha, J.N.

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

The Lateral Proximal Phalanx Flap for Contractures and Soft Tissue Defects in the Proximal Interphalangeal Joint: An Anatomical and Clinical Study.

PubMed

Beltrán, Aldo G; Romero, Camilo J

2017-01-01

Background: The management of contractures and soft tissue defects in the proximal interphalangeal (PIP) finger joint remains a challenge. We report a transposition flap from the lateral skin of the proximal phalanx that is based on perforating branches of the digital arteries and can be used safely for both palmar and dorsal cover defects. Methods: We first completed an anatomic study, dissecting 20 fingers in fresh cadavers with arterial injections and made the new flap in patients with dorsal or palmar defects in PIP joints. Results: In cadavers, we can reveal 4 constant branches from each digital artery in the proximal phalanx, with the more distal just in the PIP joint constituting the flap pedicle. Between February 2010 and February 2015, we designed 33 flaps in 29 patients, 7 for dorsal and 26 for palmar defects, with no instances of flap necrosis and 4 distal epidermolysis. The patients were between 4 and 69 years with no major complications, and all of the skin defects in the PIP joint were resolved satisfactorily without any relevant sequelae at the donor site. Conclusions: This flap procedure is an easy, reliable, versatile, and safe technique, and could be an important tool for the management of difficult skin defects and contractures at the PIP joint level.

Altered renal sodium handling and risk of incident hypertension: Results of the Olivetti Heart Study

PubMed Central

D’Elia, Lanfranco; Cappuccio, Francesco P.; Iacone, Roberto; Russo, Ornella; Galletti, Ferruccio; Strazzullo, Pasquale

2017-01-01

Renal tubular sodium (Na) handling plays a key role in blood pressure (BP) regulation. Several cross-sectional studies reported a positive association between higher proximal tubule fractional reabsorption of Na and BP, but no prospective investigation has been reported of this possible association. Hence, the purpose of this study was to estimate the predictive role of renal Na handling on the risk of incident hypertension and the changes in BP occurring in the 8-year follow-up observation of a sample of initially normotensive men (The Olivetti Heart Study). The study included 294 untreated normotensive non-diabetic men with normal renal function examined twice (1994–95 and 2002–04). Renal tubular Na handling was estimated by exogenous lithium clearance. Fractional reabsorption of Na in proximal and distal tubules was calculated and included in the analysis. At baseline, there was no association between BP and either proximal or distal fractional reabsorption of Na. At the end of the 8-year follow-up, direct associations were observed between baseline proximal (but not distal) Na fractional reabsorption and the changes occurred in systolic and diastolic BP over time (+2.79 and +1.53 mmHg, respectively, per 1SD difference in proximal Na-FR; p<0.01). Also multivariable analysis showed a direct association between baseline proximal Na fractional reabsorption and risk of incident hypertension, independently of potential confounders (OR: 1.34, 95%CI:1.06–1.70). The results of this prospective investigation strongly suggest a causal relationship between an enhanced rate of Na reabsorption in the proximal tubule and the risk of incident hypertension in initially normotensive men. PMID:28196131

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.

Theory of proximity-induced exchange coupling in graphene on hBN/(Co, Ni)

NASA Astrophysics Data System (ADS)

Zollner, Klaus; Gmitra, Martin; Frank, Tobias; Fabian, Jaroslav

2016-10-01

Graphene, being essentially a surface, can borrow some properties of an insulating substrate (such as exchange or spin-orbit couplings) while still preserving a great degree of autonomy of its electronic structure. Such derived properties are commonly labeled as proximity. Here we perform systematic first-principles calculations of the proximity exchange coupling, induced by cobalt (Co) and nickel (Ni) in graphene, via a few (up to three) layers of hexagonal boron nitride (hBN). We find that the induced spin splitting of the graphene bands is of the order of 10 meV for a monolayer of hBN, decreasing in magnitude but alternating in sign by adding each new insulating layer. We find that the proximity exchange can be giant if there is a resonant d level of the transition metal close to the Dirac point. Our calculations suggest that this effect could be present in Co heterostructures, in which a d level strongly hybridizes with the valence-band orbitals of graphene. Since this hybridization is spin dependent, the proximity spin splitting is unusually large, about 10 meV even for two layers of hBN. An external electric field can change the offset of the graphene and transition-metal orbitals and can lead to a reversal of the sign of the exchange parameter. This we predict to happen for the case of two monolayers of hBN, enabling electrical control of proximity spin polarization (but also spin injection) in graphene/hBN/Co structures. Nickel-based heterostructures show weaker proximity effects than cobalt heterostructures. We introduce two phenomenological models to describe the first-principles data. The minimal model comprises the graphene (effective) pz orbitals and can be used to study transport in graphene with proximity exchange, while the pz-d model also includes hybridization with d orbitals, which is important to capture the giant proximity exchange. Crucial to both models is the pseudospin-dependent exchange coupling, needed to describe the different spin

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

The Utility of Proximal-Accretion Stratigraphy in Lateral Moraines

NASA Astrophysics Data System (ADS)

Samolczyk, M. A.; Osborn, G.

2010-12-01

Lateral-moraine stratigraphy is a valuable tool that can be used to constrain the timing and magnitude of alpine glacier fluctuations. Numerous lateral moraines, conventionally thought to have been constructed during the Little Ice Age (LIA), have been shown to be composite landforms that contain multiple till layers deposited by successively larger glacier advances. Organic matter and/or tephra sandwiched between the till layers constrain times of advance and retreat; wood fragments within till may provide the age of the till. Observation of contemporary lateral moraines has lead to the recognition of two means of lateral moraine construction: (1) accretion of tills onto the distal flank of the pre-existing lateral moraine, and (2) accretion or plastering of tills onto the proximal flank of the pre-existing moraine. In composite lateral moraines, distal and proximal accretion result in paleosurfaces that trend parallel to the current distal and proximal slope, respectively. Published work using lateral-moraine stratigraphy, for example at Bugaboo and Stutfield glaciers in the Canadian Rockies, has used evidence only from distal-accretion moraines. However, proximal-accretion moraines that provide chronological information have been found at Nisqually Glacier on Mount Rainier in Washington State, USA, and Columbia Glacier, an outlet of the Columbia Icefield in the Canadian Rockies. A gully cut into the left-lateral moraine at Nisqually Glacier exposes a sandy seam, with associated wood fragments, that runs parallel to the proximal moraine flank for ~20 m. Wood collected from different elevations along the seam have radiocarbon ages of 1715±15, 1700±15, and 1670±50 14C yr BP, indicating that the seam is similar in age along its extent and likely marks a paleosurface separating older till below and till of the First Millennium advance above. At Columbia Glacier, some till exposures in the prominent right-lateral moraine show a fissility dipping variably 40 to 50�

Proximity hybridization-regulated chemiluminescence resonance energy transfer for homogeneous immunoassay.

PubMed

Liu, Mengmeng; Wu, Jie; Yang, Kaili; Zong, Chen; Lei, Jianping; Ju, Huangxian

2016-07-01

Chemiluminescence resonance energy transfer (CRET) and the proximity ligation assay have been widely used in design of sensors for the bioanalysis. Here, a wash-free and homogeneous strategy was proposed to detect carcino-embryonic antigen (CEA) based on proximity hybridization-regulated CRET. The Cy5 demonstrated strong chemiluminescence (CL) via the oxidation of TCPO in the presence of H2O2 and energy transfer between excited TCPO and Cy5. Graphene oxide (GO) as an excellent quencher was used to produce the "Signal off" mode that little CL emission was observed through CRET between GO and the Cy5-labelled DNA3. Once CEA was introduced, the target-induced proximity hybridization occurred to form a proximate complex, which inhibited the CRET by preventing GO from absorbing Cy5-labelled DNA3. Furthermore, taking advantage of nicking endonuclease Nt.BbvCI for in situ recycling, the signal could be further amplified for highly sensitive CL detection. Our results showed that this strategy enabled a specific response to CEA with a detection range of 5 orders of magnitude, along with a detection limit of 3.2pg mL(-1). Apart from its easy operation, high sensitivity and acceptable accuracy, the proposed method needed only 0.3μL of sample, indicating its great opportunity for commercial application. Copyright © 2016 Elsevier B.V. All rights reserved.

Extra-articular osteotomy for malunited unicondylar fractures of the proximal phalanx.

PubMed

Harness, Neil G; Chen, Alvin; Jupiter, Jesse B

2005-05-01

To evaluate an extra-articular osteotomy rather than an intra-articular osteotomy in the treatment of malunited unicondylar fractures of the proximal phalanx. An extra-articular osteotomy was used to correct the deformity resulting from a malunion of a unicondylar fracture of the proximal phalanx in 5 patients. A closing wedge osteotomy that was stabilized with tension band fixation accomplished realignment of the joint. Each patient was evaluated at a minimum of 1 year after surgery for radiographic healing, correction of angulation, digital motion, postoperative complications, current level of pain with motion, and overall satisfaction with the procedure. All of the osteotomies healed by 10 to 12 weeks after surgery with an average angular correction from 25 degrees to 1 degrees . The average proximal interphalangeal joint motion improved to 86 degrees from the preoperative average of 40 degrees , whereas the average total digital motion improved from 154 degrees before surgery to 204 degrees at follow-up evaluation. This method of extra-articular osteotomy for malunited unicondylar fractures of the proximal phalanx is highly reproducible, avoids the risks of intra-articular surgery, and leads to a predictable outcome.

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

Code of Federal Regulations, 2010 CFR

2010-01-01

... person may operate a turbine-powered airplane unless it is equipped with a ground proximity warning... system incorporates a Mode 4 flap warning inhibition control; and (2) An outline of all input sources... turbine-powered airplane unless it is equipped with a ground proximity warning/glide slope deviation...

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

Code of Federal Regulations, 2011 CFR

2011-01-01

... person may operate a turbine-powered airplane unless it is equipped with a ground proximity warning... system incorporates a Mode 4 flap warning inhibition control; and (2) An outline of all input sources... turbine-powered airplane unless it is equipped with a ground proximity warning/glide slope deviation...

Automated space vehicle control for rendezvous proximity operations

NASA Technical Reports Server (NTRS)

Lea, Robert N.

1988-01-01

Rendezvous during the unmanned space exploration missions, such as a Mars Rover/Sample Return will require a completely automatic system from liftoff to docking. A conceptual design of an automated rendezvous, proximity operations, and docking system is being implemented and validated at the Johnson Space Center (JSC). The emphasis is on the progress of the development and testing of a prototype system for control of the rendezvous vehicle during proximity operations that is currently being developed at JSC. Fuzzy sets are used to model the human capability of common sense reasoning in decision making tasks and such models are integrated with the expert systems and engineering control system technology to create a system that performs comparably to a manned system.

Automated space vehicle control for rendezvous proximity operations

NASA Technical Reports Server (NTRS)

Lea, Robert N.

1988-01-01

Rendezvous during the unmanned space exploration missions, such as a Mars Rover/Sample Return will require a completely automatic system from liftoff to docking. A conceptual design of an automated rendezvous, proximity operations, and docking system is being implemented and validated at the Johnson Space Center (JSC). The emphasis is on the progress of the development and testing of a prototype system for control of the rendezvous vehicle during proximity operations that is currently being developed at JSC. Fuzzy sets are used to model the human capability of common sense reasoning in decision-making tasks and such models are integrated with the expert systems and engineering control system technology to create a system that performs comparably to a manned system.

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.

A flexible dual-mode proximity sensor based on cooperative sensing for robot skin applications

NASA Astrophysics Data System (ADS)

Huang, Ying; Cai, Xia; Kan, Wenqing; Qiu, Shihua; Guo, Xiaohui; Liu, Caixia; Liu, Ping

2017-08-01

A flexible dual-mode proximity sensor has been designed and implemented, which is capable of combining capacitive-resistive detection in this paper. The capacitive type proximity sensor detecting is defined as mode-C, and the resistive type proximity sensor detecting is defined as mode-R. The characteristics of the proximity sensor are as follows: (1) the theoretical mode is developed which indicates that this proximity sensor can reflect proximity information accurately; (2) both sensing modes are vertically integrated into a sandwich-like chip with an 8 mm × 12 mm unit area. The thickness of a mode-R sensing material (graphene nanoplatelets) and mode-C dielectric (the mixture of carbon black and silicone rubber) is 1 mm and 2.5 mm, respectively; (3) for mode-R, the linearity of temperature-resistance curve can achieve 0.998 in the temperature range from 25°C to 65°C. And for mode-C, various materials can be successfully detected with fast response and high reversibility. Meanwhile, the study compensated the influence of object temperature to ensure mode-C properly works. A cooperative sensing test shows that R-C dual modes sense effectively which can enlarge the sensing distance compared with the single mode proximity sensor. The fabrication of this sensor is convenient, and the integrity of a flexible sandwich-like structure based on dual modes is beneficial to form arrays, which is suitable to be used in skin-like sensing applications.

Proximate and mineral composition of crab meat consumed in Bahrain.

PubMed

Musaiger, Abdulrahman O; Al-Rumaidh, Mohammed J

2005-06-01

The proximate, mineral and heavy metals of raw and cooked crab meat, Portunus pelagicus, consumed in Bahrain were studied. The crab meat contains a good level of protein (17.5-18.8%), with very low proportion of fat (0.6-1.4%). The levels of sodium, potassium, calcium and phosphorus were found to be higher than other minerals. Traces of heavy metals (lead, mercury, cadmium) were also reported. Traditional cooking had a considerable effect on proximate and mineral contents of crab meat.

An accelerated proximal augmented Lagrangian method and its application in compressive sensing.

PubMed

Sun, Min; Liu, Jing

2017-01-01

As a first-order method, the augmented Lagrangian method (ALM) is a benchmark solver for linearly constrained convex programming, and in practice some semi-definite proximal terms are often added to its primal variable's subproblem to make it more implementable. In this paper, we propose an accelerated PALM with indefinite proximal regularization (PALM-IPR) for convex programming with linear constraints, which generalizes the proximal terms from semi-definite to indefinite. Under mild assumptions, we establish the worst-case [Formula: see text] convergence rate of PALM-IPR in a non-ergodic sense. Finally, numerical results show that our new method is feasible and efficient for solving compressive sensing.

The use of cues to convergence and accommodation in naïve, uninstructed participants.

PubMed

Horwood, Anna M; Riddell, Patricia M

2008-07-01

A remote haploscopic video refractor was used to assess vergence and accommodation responses in a group of 32 emmetropic, orthophoric, symptom free, young adults naïve to vision experiments in a minimally instructed setting. Picture targets were presented at four positions between 2 m and 33 cm. Blur, disparity and looming cues were presented in combination or separately to asses their contributions to the total near response in a within-subjects design. Response gain for both vergence and accommodation reduced markedly whenever disparity was excluded, with much smaller effects when blur and proximity were excluded. Despite the clinical homogeneity of the participant group there were also some individual differences.

Proximal migration of transanastomotic pancreatic stent following pancreaticoduodenectomy and pancreaticojejunostomy.

PubMed

Ammori, B J; White, C M

1999-06-01

The use of catheters to stent the pancreaticojejunal anastomosis following pancreaticoduodenectomy is practiced by some surgeons. Their long-term effects in this setting, however, remain unknown. A 60-yr-old woman underwent a potentially curative pylorus preserving pancreaticoduodenectomy for Stage I ampullary carcinoma. Roux-en-Y pancreaticojejunostomy was constructed over a short stent. She presented 4 yr later with abdominal pain, steatorrhea, and weight loss. Computed tomography revealed a stent within the proximal pancreatic duct, with gross upstream ductal dilatation and parenchymal features of chronic pancreatitis. Laparotomy revealed no disease recurrence. The stent, removed through a jejunotomy, was occluded. On-table pancreatogram demonstrated a 3-cm proximal duct stricture. Drainage was achieved with a lateral pancreaticojejunostomy (modified Puestow procedure). Recovery was uneventful, with clinical recovery of pancreatic exocrine function at 6 mo follow-up. Proximal migration of transanastomotic pancreatic stent with subsequent development of chronic pancreatitis is a potential complication following pancreaticoduodenectomy. It can be managed effectively with stent removal and a lateral pancreaticojejunostomy.

The best location for proximal locking screw for femur interlocking nailing: A biomechanical study

PubMed Central

Karaarslan, Ahmet A; Karakaşli, Ahmet; Aycan, Hakan; Çeçen, Berivan; Yildiz, Didem Venüs; Sesli, Erhan

2016-01-01

Background: Proximal locking screw deformation and screw fracture is a frequently seen problem for femur interlocking nailing that affects fracture healing. We realized that there is lack of literature for the right level for the proximal locking screw. We investigated the difference of locking screw bending resistance between the application of screws on different proximal femoral levels. Materials and Methods: We used a total of 80 proximal locking screws for eight groups, 10 screws for each group. Three-point bending tests were performed on four types of screws in two different trochanteric levels (the lesser trochanter and 20 mm proximal). We determined the yield points at three-point bending tests that a permanent deformation started in the locking screws using an axial compression testing machine. Results: The mean yield point value of 5 mm threaded locking screws applied 20 mm proximal of lesser trochanter was 1022 ± 49 (range 986–1057) (mean ± standard deviation, 95% confidence interval). On the other hand, the mean yield point value of the same type of locking screws applied on the lesser trochanteric level was 2089 ± 249 (range 1911–2268). Which means 103% increase of screw resistance between two levels (P = 0.000). In all screw groups, on the lesser trochanter line we determined 98–174% higher than the yield point values of the same type of locking screws in comparison with 20 mm proximal to the lesser trochanter (P = 0.000). Conclusion: According to our findings, there is twice as much difference in locking screw bending resistance between these two application levels. To avoid proximal locking screw deformation, locking screws should be placed in the level of the lesser trochanter in nailing of 1/3 middle and distal femur fractures. PMID:26955183

Computed tomography-based anatomic characterization of proximal aortic dissection with consideration for endovascular candidacy.

PubMed

Moon, Michael C; Greenberg, Roy K; Morales, Jose P; Martin, Zenia; Lu, Qingsheng; Dowdall, Joseph F; Hernandez, Adrian V

2011-04-01

Proximal aortic dissections are life-threatening conditions that require immediate surgical intervention to avert an untreated mortality rate that approaches 50% at 48 hours. Advances in computed tomography (CT) imaging techniques have permitted increased characterization of aortic dissection that are necessary to assess the design and applicability of new treatment paradigms. All patients presenting during a 2-year period with acute proximal aortic dissections who underwent CT scanning were reviewed in an effort to establish a detailed assessment of their aortic anatomy. Imaging studies were assessed in an effort to document the location of the primary proximal fenestration, the proximal and distal extent of the dissection, and numerous morphologic measurements pertaining to the aortic valve, root, and ascending aorta to determine the potential for an endovascular exclusion of the ascending aorta. During the study period, 162 patients presented with proximal aortic dissections. Digital high-resolution preoperative CT imaging was performed on 76 patients, and 59 scans (77%) were of adequate quality to allow assessment of anatomic suitability for treatment with an endograft. In all cases, the dissection plane was detectable, yet the primary intimal fenestration was identified in only 41% of the studies. Scans showed 24 patients (32%) appeared to be anatomically amenable to such a repair (absence of valvular involvement, appropriate length and diameter of proximal sealing regions, lack of need to occlude coronary vasculature). Of the 42 scans that were determined not to be favorable for endovascular repair, the most common exclusion finding was the absence of a proximal landing zone (n = 15; 36%). Appropriately protocoled CT imaging provides detailed anatomic information about the aortic root and ascending aorta, allowing the assessment of which dissections have proximal fenestrations that may be amenable to an endovascular repair. Copyright © 2011 Society for

The prevalence of increased proximal junctional flexion following posterior instrumentation and arthrodesis for adolescent idiopathic scoliosis.

PubMed

Hollenbeck, S Matt; Glattes, R Christopher; Asher, Marc A; Lai, Sue Min; Burton, Douglas C

2008-07-01

Retrospective case series. To determine the prevalence of proximal junctional sagittal plane flexion increase after posterior instrumentation and arthrodesis. Increased flexion proximal to the junction of the instrumented and fused spinal region with the adjacent mobile spine seems to be a relatively recent observation, may be increasing, and is occasionally problematic. The proximal junctional sagittal angulation 2 motion segments above the upper end instrumentation levels was measured on lateral standing preoperative and follow-up radiographs. One hundred seventy-four of 208 consecutive patients (84%) at an average radiograph follow-up of 4.9 +/- 2.73 years had increased proximal junctional flexion in 9.2%. The preoperative junctional measurements were normal for both normal and increased flexion groups. At follow-up, proximal junctional flexion had increased significantly more in the increased flexion group (2.1 degrees vs. 14.1 degrees , P < 0.0001). None of the possible risk factors studied, including demographic comparisons, Lenke classification (including lumbar and sagittal modifiers), end-instrumented vertebrae, end vertebra anchor configurations, surgical sequence, additional anterior surgery, rib osteotomies, and instrumentation length, were significantly associated with increased proximal junctional flexion at follow-up. Lenke 6 curves were at marginal risk of increased proximal junctional flexion (P = 0.0108). There were no differences between the groups in total Scoliosis Research Society-22r scores at an average follow-up of 8.0 +/- 3.74 years. No patient had additional surgery related to increased proximal junctional flexion. The prevalence of increased proximal junctional flexion was 9.2%. No significant risk factors were identified. Total Scoliosis Research Society-22r scores were similar for groups with normal and increased proximal junctional flexion at follow-up.

Underexpression of the Na+-dependent neutral amino acid transporter ASCT2 in the spontaneously hypertensive rat kidney.

PubMed

Pinho, Maria João; Pinto, Vanda; Serrão, Maria Paula; Jose, Pedro A; Soares-da-Silva, Patrício

2007-07-01

This study examined the inward transport of l-[(14)C]alanine, an ASCT2 preferential substrate, in monolayers of immortalized renal proximal tubular epithelial (PTE) cells from Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. The expression of ASCT2 in WKY and SHR PTE cells and kidney cortices from WKY and SHR was also evaluated. l-[(14)C]alanine uptake was highly dependent on extracellular Na(+). Replacement of NaCl by LiCl or choline chloride abolished transport activity in SHR and WKY PTE cells. In the presence of the system L inhibitor BCH, Na(+)-dependent l-alanine uptake in WKY and SHR PTE cells was inhibited by alanine, serine, and cysteine, which is consistent with amino acid transport through ASCT2. The saturable component of Na(+)-dependent l-alanine transport under V(max) conditions in SHR PTE cells was one-half of that in WKY PTE cells, with similar K(m) values. Differences in magnitude of Na(+)-dependent l-alanine uptake through ASCT2 between WKY and SHR PTE cells correlated positively with differences in ASCT2 protein expression, this being more abundant in WKY PTE cells. Abundance of ASCT2 transcript and protein in kidney cortices of SHR rats was also lower than that in normotensive WKY rats. In conclusion, immortalized SHR and WKY PTE cells take up l-alanine mainly through a high-affinity Na(+)-dependent amino acid transporter, with functional features of ASCT2 transport. The activity and expression of the ASCT2 transporter were considerably lower in the SHR cells.

The potential and prospects of proximal remote sensing of arthropod pests.

PubMed

Nansen, Christian

2016-04-01

Bench-top or proximal remote sensing applications are widely used as part of quality control and machine vision systems in commercial operations. In addition, these technologies are becoming increasingly important in insect systematics and studies of insect physiology and pest management. This paper provides a review and discussion of how proximal remote sensing may contribute valuable quantitative information regarding identification of species, assessment of insect responses to insecticides, insect host responses to parasitoids and performance of biological control agents. The future role of proximal remote sensing is discussed as an exciting path for novel paths of multidisciplinary research among entomologists and scientists from a wide range of other disciplines, including image processing engineers, medical engineers, research pharmacists and computer scientists. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Modified rush pin technique for two- or three-part proximal humeral fractures.

PubMed

Mallick, A; Hearth, M; Singh, S; Pandey, R

2008-12-01

To report the outcomes of modified Rush pin fixation for proximal humeral fractures. 42 men and 20 women aged 19 to 94 (mean, 64) years with 2- or 3-part proximal humeral fractures underwent reduction and fixation using the modified Rush pin technique. 11 patients died from reasons unrelated to the surgery. Of 40 (out of 51) patients completing a subjective functional assessment using an Oxford Shoulder Questionnaire, 28 (70%) had 2-part and 10 (25%) had 3-part displaced fractures, and the remaining 2 (5%) had fracture-dislocations (one being 2-part and one 3-part). 25 (63%) patients were very satisfied (including one with a 3-part fracture after 6 months of rehabilitation), 7 (17%) were moderately satisfied, and 8 (20%) were not satisfied. There were 8 complications, including pin cut-out from the proximal fragment (n=2), proximal pin migration (n=2), distal pin migration (n=1), cortical perforation during surgery (n=1), mild ulnar nerve symptoms (n=1). No patients had non-union, myositis ossificans, avascular necrosis of the humeral head, or axillary nerve injury. The modified Rush pin fixation minimises tissue dissection; the implants are cheap and readily available; and the technical expertise is easily learnt. This technique is a suitable alternative of fixing proximal humeral fractures, especially in the elderly.

Proximal hamstring morphology and morphometry in men: an anatomic and MRI investigation.

PubMed

Storey, R N; Meikle, G R; Stringer, M D; Woodley, S J

2016-12-01

The proximal musculo-tendinous junction (MTJ) is a common site of hamstring strain injury but the anatomy of this region is not well defined. A morphometric analysis of the proximal MTJs of biceps femoris long head (BFlh), semitendinosus (ST), and semimembranosus (SM) was undertaken from dissection of 10 thighs from five male cadavers and magnetic resonance imaging of 20 thighs of 10 active young men. The length, volume, and cross-sectional area of the proximal tendon, MTJ and muscle belly, and muscle-tendon interface area were calculated. In both groups, MTJs were reconstructed three-dimensionally. The proximal tendons and MTJs were expansive, particularly within SM and BFlh. Morphology varied between muscles although length measurements within individual muscles were similar in cadavers and young men. Semimembranosus had the longest proximal tendon (cadavers: mean 33.6 ± 2.0 cm; young men: mean 31.7 ± 1.6 cm) and MTJ (>20 cm in both groups) and the greatest muscle-tendon interface area, followed by BFlh and ST. Mean muscle belly volumes were more than three times greater in young men than elderly male cadavers (P < 0.001). These unique morphometric data contribute to a better understanding of hamstring anatomy, an important factor in the pathogenesis of hamstring strain injury. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Proximal gastric motility in critically ill patients with type 2 diabetes mellitus.

PubMed

Nguyen, Nam Q; Fraser, Robert J; Bryant, Laura K; Chapman, Marianne; Holloway, Richard H

2007-01-14

To investigate the proximal gastric motor response to duodenal nutrients in critically ill patients with long-standing type 2 diabetes mellitus. Proximal gastric motility was assessed (using a barostat) in 10 critically ill patients with type 2 diabetes mellitus (59 +/- 3 years) during two 60-min duodenal infusions of Ensure (1 and 2 kcal/min), in random order, separated by 2 h fasting. Data were compared with 15 non-diabetic critically ill patients (48 +/- 5 years) and 10 healthy volunteers (28 +/- 3 years). Baseline proximal gastric volumes were similar between the three groups. In diabetic patients, proximal gastric relaxation during 1 kcal/min nutrient infusion was similar to non-diabetic patients and healthy controls. In contrast, relaxation during 2 kcal/min infusion was initially reduced in diabetic patients (P < 0.05) but increased to a level similar to healthy humans, unlike non-diabetic patients where relaxation was impaired throughout the infusion. Duodenal nutrient stimulation reduced the fundic wave frequency in a dose-dependent fashion in both the critically ill diabetic patients and healthy subjects, but not in critically ill patients without diabetes. Fundic wave frequency in diabetic patients and healthy subjects was greater than in non-diabetic patients. In patients with diabetes mellitus, proximal gastric motility is less disturbed than non-diabetic patients during critical illness, suggesting that these patients may not be at greater risk of delayed gastric emptying.

Activation of an ATP-dependent K(+) conductance in Xenopus oocytes by expression of adenylate kinase cloned from renal proximal tubules.

PubMed

Brochiero, E; Coady, M J; Klein, H; Laprade, R; Lapointe, J Y

2001-02-09

In rabbit proximal convoluted tubules, an ATP-sensitive K(+) (K(ATP)) channel has been shown to be involved in membrane cross-talk, i.e. the coupling (most likely mediated through intracellular ATP) between transepithelial Na(+) transport and basolateral K(+) conductance. This K(+) conductance is inhibited by taurine. We sought to isolate this K(+) channel by expression cloning in Xenopus oocytes. Injection of renal cortex mRNA into oocytes induced a K(+) conductance, largely inhibited by extracellular Ba(2+) and intracellular taurine. Using this functional test, we isolated from our proximal tubule cDNA library a unique clone, which induced a large K(+) current which was Ba(2+)-, taurine- and glibenclamide-sensitive. Surprisingly, this clone is not a K(+) channel but an adenylate kinase protein (AK3), known to convert NTP+AMP into NDP+ADP (N could be G, I or A). AK3 expression resulted in a large ATP decrease and activation of the whole-cell currents including a previously unknown, endogenous K(+) current. To verify whether ATP decrease was responsible for the current activation, we demonstrated that inhibition of glycolysis greatly reduces oocyte ATP levels and increases an inwardly rectifying K(+) current. The possible involvement of AK in the K(ATP) channel's regulation provides a means of explaining their observed activity in cytosolic environments characterized by high ATP concentrations.

Transverse preputial onlay island flap urethroplasty for single-stage correction of proximal hypospadias.

PubMed

Singal, Arbinder Kumar; Dubey, Manish; Jain, Viral

2016-07-01

Transverse preputial onlay island flap urethroplasty (TPOIF) was described initially for distal hypospadias, but has seen extended application for proximal hypospadias. We describe a set of modifications in the technique and results in a large series of proximal hypospadias. All children who underwent TPOIF repair for proximal hypospadias (proximal penile, penoscrotal and scrotal) from June 2006 to June 2013 by a single surgeon were prospectively followed till June, 2014. A standard technique and postoperative protocol were followed. Salient points to be emphasized in the technique: (1) dissection of the dartos pedicle till penopubic junction to prevent penile torsion, (2) incorporation of the spongiosum in the urethroplasty, (3) midline urethral plate incision in glans (hinging the plate), (4) Dartos blanket cover on whole urethroplasty. Out of 136 children with proximal hypospadias, 92 children who underwent TPOIF formed the study group. Out of 92 children, 48 (52 %) children required a tunica albuginea plication for chordee correction. In total, 16 (17 %) patients developed 24 complications and 11 children (12 %) required second surgeries: fistula closure in 7 (with meatoplasty in 5), glansplasty for glans dehiscence in 2 and excision of diverticulum in 2. Two children required a third surgery. Only 5 children had a noticeable penile torsion (less than 30 degree), and 7 had a patulous meatus. Transverse preputial onlay island flap urethroplasty can deliver reliable cosmetic and functional outcomes in proximal hypospadias.

Proximal attrition facets: morphometric, demographic, and aging characteristics.

PubMed

Sarig, Rachel; Hershkovitz, Israel; Shvalb, Nir; Sella-Tunis, Tatiana; May, Hila; Vardimon, Alexander D

2014-08-01

Although interproximal attrition is considered to be limited in modern populations, it has important clinical implications. However, in contrast to occlusal attrition, proximal attrition receives limited scientific attention. The main purpose of the current study was to fill this void. Seven-hundred and sixty-five teeth were collected from 255 skulls of subjects 18-75 yr of age. For each individual, three mandibular teeth (the first and second premolars and the first molar) were examined for proximal attrition facets (PAFs). The results provide detailed information on the size, shape, and location of the facets according to age cohort, gender, and ethnicity. The validity of the method used to measure the facets was also examined. The major findings were as follows: PAFs are usually located on the upper half of the crown proximal aspect; in each tooth, the mesial facet is more lingually positioned and the distal facet is more buccally positioned; the majority of the facets are subrectangular in shape; the size of the facets tends to increase in an anteroposterior direction (from premolars to molars); and facet size and location are age- and sex-dependent and ethnicity-independent. It is our recommendation that dentists bear in mind that interproximal attrition is a dynamic, long-term process and needs to be considered in many clinical scenarios. © 2014 Eur J Oral Sci.

Diadenosine polyphosphate-stimulated gluconeogenesis in isolated rat proximal tubules.

PubMed Central

Edgecombe, M; Craddock, H S; Smith, D C; McLennan, A G; Fisher, M J

1997-01-01

Diadenosine polyphosphates released into the extracellular environment influence a variety of metabolic and other cellular activities in a wide range of target tissues. Here we have studied the impact of these novel nucleotides on gluconeogenesis in isolated rat proximal tubules. Gluconeogenesis was stimulated following exposure of isolated proximal tubules to a range of adenine-containing nucleotides including ADP, ATP, Ap3A, Ap4A, Ap5A and Ap6A. The concentration-dependence of ATP-, Ap3A- and Ap4A-mediated stimulation of gluconeogenesis was similar and was consistent with a role for these agents in the physiological control of renal metabolism. Nucleotide-stimulated gluconeogenesis was diminished in the presence of agents that interfere with phospholipase C activation or intracellular Ca2+ metabolism, indicative of a role for polyphosphoinositide-mediated Ca2+ mobilization in the mechanism of action of ATP, Ap3A and Ap4A. The characteristics of binding of [2-3H]Ap4A to renal plasma-membrane preparations suggest that Ap4A mediates its effects on proximal tubule gluconeogenesis via interaction with P2y-like purinoceptor(s) also recognized by extracellular ATP. PMID:9163337

Spatial versus Tree Representations of Proximity Data.

ERIC Educational Resources Information Center

Pruzansky, Sandra; And Others

1982-01-01

Two-dimensional euclidean planes and additive trees are two of the most common representations of proximity data for multidimensional scaling. Guidelines for comparing these representations and discovering properties that could help identify which representation is more appropriate for a given data set are presented. (Author/JKS)

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.

Novel Surgical Technique for Coronary Fistulas With Proximal Origin.

PubMed

Uchida, Tetsuro; Hamasaki, Azumi; Kuroda, Yoshinori; Ohba, Eiichi; Yamashita, Atsushi; Sadahiro, Mitsuaki

2017-09-01

Postoperative residual shunting is a significant concern in patients with coronary arteriovenous fistulas, especially in fistulas originating from the proximal left coronary artery, because of the limited surgical field. We report a case of fistulas originating from the proximal coronary artery in a 63-year-old woman in whom the ascending aorta and pulmonary artery were transected to obtain good surgical exposure. After complete transection of both great arteries, fistulas arising from the left main trunk were ligated externally, and their intracardiac openings were closed internally. Postoperative examination revealed no residual shunt flow. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

True aneurysm of the proximal occipital artery: Case report.

PubMed

Illuminati, Giulio; Cannistrà, Marco; Pizzardi, Giulia; Pasqua, Rocco; Frezzotti, Francesca; Calio', Francesco G

2018-01-01

True aneurysms of the proximal occipital artery are rare, may cause neurological symptoms due to compression of the hypoglossal nerve and their resection may be technically demanding. The case of an aneurysm of the proximal occipital artery causing discomfort and tongue deviation by compression on the hypoglossal nerve is reported. Postoperative course after resection was followed by complete regression of symptoms. Surgical resection, as standard treatment of aneurysms of the occipital artery, with the eventual technical adjunct of intubation by the nose is effective in durably relieving symptoms and preventing aneurysm-related complication. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

The outcome of unstable proximal femoral fracture treated with reverse LISS plates.

PubMed

Lin, Shih-Jie; Huang, Kuo-Chin; Chuang, Po-Yao; Lee, Chien-Yin; Huang, Tsan-Wen; Lee, Mel S; Hsu, Robert Wen-Wei

2016-10-01

The Russel-Taylor type 2B fractures compromised the trochanteric region and medial buttress of proximal femur. This fracture pattern limits the choice of implants and raises the risk of adverse outcomes. We aimed to (i) determine the outcome of Russel-Taylor type 2B fractures treated using reverse less invasive stabilization system plates (LISS-DF) and to (ii) learn what factors affected outcomes after osteosynthesis with reverse LISS plates. A retrospective study SETTING: The study was conducted at a Level III trauma center in Taiwan. Twenty-five consecutive patients presenting with a Russel-Taylor type 2B fracture were enrolled. All cases were treated with reverse LISS plates. A Modified Radiographic Union Scale for Femur (RUSF), Radiographic parameters, functional scores, and complications were assessed. Union occurred in 21 cases at an average of 18.8 weeks. The average immediate postoperative neck-shaft angle was 130° (range: 122-135°) compared with 139° (range: 135-141°, p=0.05) on the contralateral side. Two cases had complications of proximal screws cutting out and two cases had broken implants. Finally, all 4 cases required repeated surgeries (16%). Malunion occurred in 4 patients and early mechanical failure (proximal screws cut out) occurred in 2. There was a significant difference in the purchase index of the proximal screws between cases with redisplacement and those without (26.4mm and 98.6mm, p=0.01). The use of reverse LISS plate appeared to be an alternative procedure for the specific pattern in the present study. We recommend using this reverse locking plate to treat unstable proximal femoral fractures with meticulous techniques of placing plates. Adequate purchase of the proximal locking screws might decrease the risks of complications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Geometrical correction of the e-beam proximity effect for raster scan systems

NASA Astrophysics Data System (ADS)

Belic, Nikola; Eisenmann, Hans; Hartmann, Hans; Waas, Thomas

1999-06-01

Increasing demands on pattern fidelity and CD accuracy in e- beam lithography require a correction of the e-beam proximity effect. The new needs are mainly coming from OPC at mask level and x-ray lithography. The e-beam proximity limits the achievable resolution and affects neighboring structures causing under- or over-exposion depending on the local pattern densities and process settings. Methods to compensate for this unequilibrated does distribution usually use a dose modulation or multiple passes. In general raster scan systems are not able to apply variable doses in order to compensate for the proximity effect. For system of this kind a geometrical modulation of the original pattern offers a solution for compensation of line edge deviations due to the proximity effect. In this paper a new method for the fast correction of the e-beam proximity effect via geometrical pattern optimization is described. The method consists of two steps. In a first step the pattern dependent dose distribution caused by back scattering is calculated by convolution of the pattern with the long range part of the proximity function. The restriction to the long range part result in a quadratic sped gain in computing time for the transformation. The influence of the short range part coming from forward scattering is not pattern dependent and can therefore be determined separately in a second step. The second calculation yields the dose curve at the border of a written structure. The finite gradient of this curve leads to an edge displacement depending on the amount of underground dosage at the observed position which was previously determined in the pattern dependent step. This unintended edge displacement is corrected by splitting the line into segments and shifting them by multiples of the writers address grid to the opposite direction.

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.

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.

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.

Mucosal integrity and sensitivity to acid in the proximal esophagus in patients with gastroesophageal reflux disease.

PubMed

van Hoeij, Froukje B; Weijenborg, Pim W; van den Bergh Weerman, Marius A; van den Wijngaard, René M J G J; Verheij, J; Smout, André J P M; Bredenoord, Albert J

2016-07-01

Acid reflux episodes that extend to the proximal esophagus are more likely to be perceived. This suggests that the proximal esophagus is more sensitive to acid than the distal esophagus, which could be caused by impaired mucosal integrity in the proximal esophagus. Our aim was to explore sensitivity to acid and mucosal integrity in different segments of the esophagus. We used a prospective observational study, including 12 patients with gastroesophageal reflux disease (GERD). After stopping acid secretion-inhibiting medication, two procedures were performed: an acid perfusion test and an upper endoscopy with electrical tissue impedance spectroscopy and esophageal biopsies. Proximal and distal sensitivity to acid and tissue impedance were measured in vivo, and mucosal permeability and epithelial intercellular spaces at different esophageal levels were measured in vitro. Mean lag time to heartburn perception was much shorter after proximal acid perfusion (0.8 min) than after distal acid perfusion (3.9 min) (P = 0.02). Median in vivo tissue impedance was significantly lower in the distal esophagus (4,563 Ω·m) compared with the proximal esophagus (8,170 Ω·m) (P = 0.002). Transepithelial permeability, as measured by the median fluorescein flux was significantly higher in the distal (2,051 nmol·cm(-2)·h(-1)) than in the proximal segment (368 nmol·cm(-2)·h(-1)) (P = 0.033). Intercellular space ratio and maximum heartburn intensity were not significantly different between the proximal and distal esophagus. In GERD patients off acid secretion-inhibiting medication, acid exposure in the proximal segment of the esophagus provokes symptoms earlier than acid exposure in the distal esophagus, whereas mucosal integrity is impaired more in the distal esophagus. These findings indicate that the enhanced sensitivity to proximal reflux episodes is not explained by increased mucosal permeability. Copyright © 2016 the American Physiological Society.

Proximal Femoral Reconstructions with Bone Impaction Grafting and Metal Mesh

PubMed Central

Comba, Fernando; Piccaluga, Francisco

2009-01-01

Extensive circumferential proximal cortical bone loss is considered by some a contraindication for impaction bone grafting in the femur. We asked whether reconstruction with a circumferential metal mesh, impacted bone allografts, and a cemented stem would lead to acceptable survival in these patients. We retrospectively reviewed 14 patients (15 hips) with severe proximal femoral bone defects (average, 12 cm long; 14 type IV and one type IIIB using the classification of Della Valle and Paprosky) reconstructed with this method. The minimum followup was 20 months (average, 43.2 months; range, 20–72 months). Preoperative Merle D’Aubigné and Postel score averaged 4.8 points. With revision of the stem as the end point, the survivorship of the implant was 100% at one year and 86.6% at 72 months. The mean functional score at last followup was 14.4 points. We observed two fractures of the metal mesh at 31 and 48 months in cases reconstructed with a stem that did not bypass the mesh. Dislocation (3 cases) and acute deep infection (3 cases) were the most frequent complications. Patients with complete absence of the proximal femur may be candidates for biological proximal femoral reconstructions using this salvage procedure. Bone impaction grafting must be a routine technique if this method is selected. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:19294476

Antagonistic actions of renal dopamine and 5-hydroxytryptamine: increase in Na+, K(+)-ATPase activity in renal proximal tubules via activation of 5-HT1A receptors.

PubMed Central

Soares-da-Silva, P.; Pinto-do-O, P. C.; Bertorello, A. M.

1996-01-01

1. 5-Hydroxytryptamine (5-HT) is antinatriuretic. Since this effect of 5-HT is not accomplished by changes in glomerular haemodynamics, we have examined in this study whether 5-HT may influence sodium excretion by affecting the Na+, K(+)-ATPase activity in renal cortical tubules. 2. Na+, K(+)-ATPase activity was determined as the rate of [32P]-ATP hydrolysis in renal cortical tubules in suspension. Basal Na+, K(+)-ATPase activity in renal tubules was 4.8 +/- 0.4 mumol Pi mg-1 protein h-1 (n = 8). The 5-HT1A receptor agonist, (+/-)-8-hydroxy-2-(di-n-propylamino) tetraline (8-OH-DPAT) (10 to 3000 nM) induced a concentration-dependent increase (P < 0.05) in Na+, K(+)-ATPase activity with an EC50 value of 355 nM (95% confidence limits: 178, 708). Maximal stimulation elicited by 3000 nM of 8-OH-DPAT was antagonized by the selective 5-HT1A receptor antagonist, (+)-WAY 100135 10 to 1000 nM) with an IC50 value of 20 nM (14, 29); 0.3 microM (+)-WAY 100135 completely abolished (P < 0.01) the stimulatory effect of 8-OH-DPAT. The stimulatory effect of 8-OH-DPAT was found to be time-dependent (15 +/- 2% and 66 +/- 7% increase at 2.5 and 5.0 min, respectively). The 5-HT2 receptor agonist alpha-methyl-5-HT (100 to 3000 nM) did not induce any significant changes in Na+, K(+)-ATPase activity (5.0 +/- 1.5 mumol Pi mg-1 protein h-1; n = 4). 3. The stimulatory effect 8-OH-DPAT was absent when homogenates were used. Stimulation occurred at a Vmax concentration (70 mM) of sodium supporting the notion that stimulation occurs independently of increasing sodium permeability. 4. The inhibitory effect of dopamine (P < 0.05) on Na+, K(+)-ATPase activity was blunted by co-incubation with 8-OH-DPAT (0.5 microM). 5. It is concluded that activation of 5-HT1A receptors increases Na+, K(+)-ATPase activity in renal cortical tubules; this effect may represent an important cellular mechanism, at the tubule level, responsible for the antinatriuretic effect of 5-HT. Images Figure 4 PMID:8882616

Proximity fuze

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 lightmore » 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.« less

Proximity fuze

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harrison, T.R.

1989-08-22

A proximity fuze system is described. It 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 dependingmore » 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.« less

DO PROXIMAL AND DISTAL GASTRIC TUMOURS BEHAVE DIFFERENTLY?

PubMed

Costa, Laurence Bedin da; Toneto, Marcelo Garcia; Moreira, Luis Fernando

2016-01-01

Although the incidence of gastric (adenocarcinoma) cancer has been decreasing over time, it is still one of the most common malignancies worldwide, and proximal tumours tend to have a worse prognosis. To compare surgical outcomes and prognosis between proximal - excluding tumours of the cardia - and distal gastric cancer. Out of 293 cases reviewed - 209 with distal and 69 with proximal gastric cancer - were compared for clinical and pathological features, stage, surgical outcome, mortality and survival. Statistically, there was no significant difference between patients in both groups regarding mortality (p=0.661), adjuvant chemotherapy (p 0.661), and radiation (p=1.000). However, there was significant difference in the degree of lymph node dissection employed (p=0.002) and the number of positive lymph nodes resected (p=0.038) between the two groups. The odds of death at five years for patients who had a D0 dissection was three times greater (odds ratio 2.78; (95%CI 1.33-5.82) than that for patients who had a D2 dissection, while for patients who had a D1 dissection the odds ratio was only 1.41 (95%CI 0.71-2.83) compared to D2-dissected patients. Although no significant differences were found between proximal and distal gastric cancer, the increased risk of death in D0- and D1-dissected patients clearly suggests an important role of radical D2 lymph node dissection in survival. Embora a incidência do câncer gástrico esteja diminuindo nas últimas décadas, ele ainda aparece como uma das neoplasias malignas mais comuns, e tumores proximais tendem a ter pior prognóstico. Comparar os resultados cirúrgicos e o prognóstico entre o câncer gástrico proximal, excluindo os tumores da cárdia e junção esofagogástrica, e o distal. De 293 casos revistos - 209 distais e 69 proximais - foram comparados quanto aos achados clínicos e patológicos, estágio, resultados cirúrgicos, mortalidade e sobrevida. Estatisticamente não houve diferença entre pacientes em ambos

Orbiter/payload proximity operations SES Postsim report. Lateral approach and other techniques

NASA Technical Reports Server (NTRS)

Olszewski, O.

1978-01-01

Various approach and stationkeeping simulations (proximity operations) were conducted in the Shuttle engineering simulator (SES). This simulator is the first to dynamically include the Orbiter reaction control system (RCS) plume effects on a payload being recovered after rendezvous operations. A procedure for braking, using the simultaneous firing of both jets, was evaluated and found very useful for proximity operations. However this procedure is very inefficient in the RCS usage and requires modifications to the digital autopilot (DAP) software. A new final approach, the lateral approach technique (LAT), or the momentum vector proximity approach, was also evaluated in the simulations. The LAT, which included a tailfirst approach for braking, was evaluated successfully with both inertial and gravity stabilized payloads.

Adaptive multiphoton endomicroscopy through a dynamically deformed multicore optical fiber using proximal detection.

PubMed

Warren, Sean C; Kim, Youngchan; Stone, James M; Mitchell, Claire; Knight, Jonathan C; Neil, Mark A A; Paterson, Carl; French, Paul M W; Dunsby, Chris

2016-09-19

This paper demonstrates multiphoton excited fluorescence imaging through a polarisation maintaining multicore fiber (PM-MCF) while the fiber is dynamically deformed using all-proximal detection. Single-shot proximal measurement of the relative optical path lengths of all the cores of the PM-MCF in double pass is achieved using a Mach-Zehnder interferometer read out by a scientific CMOS camera operating at 416 Hz. A non-linear least squares fitting procedure is then employed to determine the deformation-induced lateral shift of the excitation spot at the distal tip of the PM-MCF. An experimental validation of this approach is presented that compares the proximally measured deformation-induced lateral shift in focal spot position to an independent distally measured ground truth. The proximal measurement of deformation-induced shift in focal spot position is applied to correct for deformation-induced shifts in focal spot position during raster-scanning multiphoton excited fluorescence imaging.

Stercoral perforation of the colon proximal to an end colostomy.

PubMed Central

Serpell, J. W.; Sen, M.; Giddins, G.; Nicholls, R. J.; Bradfield, W. J.

1991-01-01

Stercoral perforation of the colon is rare, and has not previously been reported as a postoperative complication, proximal to an end colostomy. Two such cases are reported; in addition in one the stercoral perforation was recurrent, emphasizing the multifocal nature of the disease. Both cases demonstrate the failure of standard techniques to deal with scybala in the loaded proximal colon. It is, therefore, suggested that intra-operative orthograde colonic lavage is indicated to protect a terminal colostomy from the risk of stercoral perforation in such cases. PMID:2062783

Bioprinting of 3D Convoluted Renal Proximal Tubules on Perfusable Chips

NASA Astrophysics Data System (ADS)

Homan, Kimberly A.; Kolesky, David B.; Skylar-Scott, Mark A.; Herrmann, Jessica; Obuobi, Humphrey; Moisan, Annie; Lewis, Jennifer A.

2016-10-01

Three-dimensional models of kidney tissue that recapitulate human responses are needed for drug screening, disease modeling, and, ultimately, kidney organ engineering. Here, we report a bioprinting method for creating 3D human renal proximal tubules in vitro that are fully embedded within an extracellular matrix and housed in perfusable tissue chips, allowing them to be maintained for greater than two months. Their convoluted tubular architecture is circumscribed by proximal tubule epithelial cells and actively perfused through the open lumen. These engineered 3D proximal tubules on chip exhibit significantly enhanced epithelial morphology and functional properties relative to the same cells grown on 2D controls with or without perfusion. Upon introducing the nephrotoxin, Cyclosporine A, the epithelial barrier is disrupted in a dose-dependent manner. Our bioprinting method provides a new route for programmably fabricating advanced human kidney tissue models on demand.

Growth of binary organic NLO crystals: m.NA-p.NA and m.NA-CNA system

NASA Technical Reports Server (NTRS)

Singh, N. B.; Henningsen, T.; Hopkins, R. H.; Mazelsky, R.

1993-01-01

Experiments were carried out to grow 3.Nitroaniline (m.NA) crystals doped with 4.Nitroaniline (p.NA) and 2.chloro 4.Nitroaniline (CNA). The measured undercooling for m.NA, p.NA, and CNA were 0.21 tm K, 0.23 tm K, and 0.35 tm K respectively, where tm represents the melting temperature of the pure component. Because of the crystals' large heat of fusion and large undercooling, it was not possible to grow good quality crystals with low thermal gradients. In the conventional two-zone Bridgman furnace we had to raise the temperature of the hot zone above the decomposition temperature of CNA, p.NA, and m.NA to achieve the desired thermal gradient. To avoid decomposition, we used an unconventional Bridgman furnace. Two immiscible liquids, silicone oil and ethylene glycol, were used to build a special two-zone Bridgman furnace. A temperature gradient of 18 K/cm was achieved without exceeding the decomposition temperature of the crystal. The binary crystals, m.NA-p.NA and m.NA-CNA, were grown in centimeter size in this furnace. X-ray and optical characterization showed good optical quality.

Esophagogastrostomy plus gastrojejunostomy: a novel reconstruction procedure after curative resection for proximal gastric cancer.

PubMed

Chen, Shicai; Li, Jianchang; Liu, Haiying; Zeng, Jun; Yang, Guohua; Wang, Jin; Lu, Weiqun; Yu, Nanrong; Huang, Zhiliang; Xu, Houwei; Zeng, Xiang

2014-03-01

The choice of surgical strategy for patients with proximal gastric cancer remains controversial. In this study, we recommend that a new reconstruction procedure be performed following proximal gastrectomy. We conducted a retrospective study involving 71 patients who underwent gastrectomy for proximal gastric cancer. Clinicopathological features, postoperative complications, nutritional status, and overall survival (OS) rate were compared among three different reconstruction approaches. There were 34 cases of proximal gastrectomy followed by esophagogastrostomy reconstruction (EG), 16 cases of total gastrectomy and Roux-en Y reconstruction (RY) and 21 cases of proximal gastrectomy followed by esophagogastrostomy plus gastrojejunostomy reconstruction (EGJ). Though the clinicopathological features, the nutritional status and OS rate were similar among the three groups of patients, the incidence of reflux esophagitis was significantly higher in the EG group (35.3%) than the RY (6.2%) and EGJ (9.6%) groups(P < 0.05). Few EGJ patients suffered from either reflux esophagitis or anastomotic stenosis. The EGJ reconstruction method helps to resolve the syndrome of reflux esophagitis. Our data indicates that it is a simple, safe, and effective reconstruction procedure for PGC.

Thermal decomposition of sodium amide, NaNH2, and sodium amide hydroxide composites, NaNH2-NaOH.

PubMed

Jepsen, Lars H; Wang, Peikun; Wu, Guotao; Xiong, Zhitao; Besenbacher, Flemming; Chen, Ping; Jensen, Torben R

2016-09-14

Sodium amide, NaNH 2 , has recently been shown to be a useful catalyst to decompose NH 3 into H 2 and N 2 , however, sodium hydroxide is omnipresent and commercially available NaNH 2 usually contains impurities of NaOH (<2%). The thermal decomposition of NaNH 2 and NaNH 2 -NaOH composites is systematically investigated and discussed. NaNH 2 is partially dissolved in NaOH at T > 100 °C, forming a non-stoichiometric solid solution of Na(OH) 1-x (NH 2 ) x (0 < x < ∼0.30), which crystallizes in an orthorhombic unit cell with the space group P2 1 2 1 2 1 determined by synchrotron powder X-ray diffraction. The composite xNaNH 2 -(1 - x)NaOH (∼0.70 < x < 0.72) shows a lowered melting point, ∼160 °C, compared to 200 and 318 °C for neat NaNH 2 and NaOH, respectively. We report that 0.36 mol of NH 3 per mol of NaNH 2 is released below 400 °C during heating in an argon atmosphere, initiated at its melting point, T = 200 °C, possibly due to the formation of the mixed sodium amide imide solid solution. Furthermore, NaOH reacts with NaNH 2 at elevated temperatures and provides the release of additional NH 3 .

Proximal Corporal Perforation During Penile Prosthesis Surgery: Prevention, Recognition, and Review of Historical and Novel Management Strategies.

PubMed

Pearlman, Amy M; Terlecki, Ryan P

2018-05-02

Proximal corporal perforation at time of dilation, although rare, may occur due to factors related to patient anatomy, presence of intra-cavernosal fibrosis, and/or surgical technique. To describe tools and techniques designed to prevent and identify proximal corporal perforation, and maneuvers to minimize the risk of subsequent cylinder migration once proximal perforation has been recognized, such that the operation may proceed and result in an acceptable outcome. We discuss tips for prevention, recognition, and management of proximal corporal perforation by presenting a review of the literature as well as our preferences based on a high-volume experience with penile prosthesis surgery. Described techniques aim to minimize risk of cylinder migration in the absence of true proximal repair. Although proximal perforation may be obvious at times, particularly with a sudden loss of resistance during dilation, discrepant corporal measurements and/or dissimilar proximal deflection of the dilator should also increase the index of suspicion. Numerous techniques have been employed to theoretically reduce the risk of cylinder migration in the setting of proximal corporal perforation. These include formal corporal repair (historical), windsock repairs with non-absorbable grafts, absorbable plugs, and suture fixation of the rear tip extender or shod material covering implant tubing. Intra-operative recognition of proximal corporal perforation, coupled with understanding of surgical strategies to minimize the risk of future device migration, may allow completion of an operation that still results in an optimal outcome. Techniques described to prevent proximal migration are not strongly evidence-based, but rooted in logic and supported by high-volume implanters. Intra-operative perforation of the proximal corpora, although rare, can threaten the success of penile implant surgery, though the techniques described herein have been developed to mitigate the potential for subsequent

Condition of Si crystal formation by vaporizing Na from NaSi

NASA Astrophysics Data System (ADS)

Morito, Haruhiko; Karahashi, Taiki; Yamane, Hisanori

2012-09-01

NaSi was heated at various Na vapor pressures (pNa 0.1-1.2 atm) and temperatures (973-1173 K) to investigate the condition of Si crystal formation from NaSi by Na evaporation. Silicon single crystals 1-3 mm in diameter were grown by evaporation of Na from Na-Si melt at 1173 K and pNa=0.74 atm.

Proximal Bright Vessel Sign on Arterial Spin Labeling Magnetic Resonance Imaging in Acute Cardioembolic Cerebral Infarction.

PubMed

Kato, Ayumi; Shinohara, Yuki; Kuya, Keita; Sakamoto, Makoto; Kowa, Hisanori; Ogawa, Toshihide

2017-07-01

The congestion of spin-labeled blood at large-vessel occlusion can present as hyperintense signals on perfusion magnetic resonance imaging with 3-dimensional pseudo-continuous arterial spin labeling (proximal bright vessel sign). The purpose of this study was to clarify the difference between proximal bright vessel sign and susceptibility vessel sign in acute cardioembolic cerebral infarction. Forty-two patients with cardioembolic cerebral infarction in the anterior circulation territory underwent magnetic resonance imaging including diffusion-weighted imaging, 3-dimensional pseudo-continuous arterial spin labeling perfusion magnetic resonance imaging, T2*-weighted imaging, and 3-dimensional time-of-flight magnetic resonance angiography using a 3-T magnetic resonance scanner. Visual assessments of proximal bright vessel sign and the susceptibility vessel sign were performed by consensus of 2 experienced neuroradiologists. The relationship between these signs and the occlusion site of magnetic resonance angiography was also investigated. Among 42 patients with cardioembolic cerebral infarction, 24 patients showed proximal bright vessel sign (57.1%) and 25 showed susceptibility vessel sign (59.5%). There were 19 cases of proximal bright vessel sign and susceptibility vessel sign-clear, 12 cases of proximal bright vessel sign and susceptibility vessel sign-unclear, and 11 mismatched cases. Four out of 6 patients with proximal bright vessel sign-unclear and susceptibility vessel sign-clear showed distal middle cerebral artery occlusion, and 2 out of 5 patients with proximal bright vessel sign-clear and susceptibility vessel sign-unclear showed no occlusion on magnetic resonance angiography. Proximal bright vessel sign is almost compatible with susceptibility vessel sign in patients with cardioembolic cerebral infarction. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Sodium iron hexacyanoferrate with high Na content as a Na-rich cathode material for Na-ion batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

You, Ya; Yu, Xi -Qian; Yin, Ya -Xia

Owing to the worldwide abundance and low-cost of Na, room-temperature Na-ion batteries are emerging as attractive energy storage systems for large-scale grids. Increasing the Na content in cathode material is one of the effective ways to achieve high energy density. Prussian blue and its analogues (PBAs) are promising Na-rich cathode materials since they can theoretically store two Na ions per formula. However, increasing the Na content in PBAs cathode materials is a big challenge in the current. Here we show that sodium iron hexacyanoferrate with high Na content could be obtained by simply controlling the reducing agent and reaction atmospheremore » during synthesis. The Na content can reach as high as 1.63 per formula, which is the highest value for sodium iron hexacyanoferrate. This Na-rich sodium iron hexacyanoferrate demonstrates a high specific capacity of 150 mA h g -1 and remarkable cycling performance with 90% capacity retention after 200 cycles. Furthermore, the Na intercalation/de-intercalation mechanism is systematically studied by in situ Raman, X-ray diffraction and X-ray absorption spectroscopy analysis for the first time. As a result, the Na-rich sodium iron hexacyanoferrate could function as a plenteous Na reservoir and has great potential as a cathode material toward practical Na-ion batteries.« less

Sodium iron hexacyanoferrate with high Na content as a Na-rich cathode material for Na-ion batteries

DOE PAGES

You, Ya; Yu, Xi -Qian; Yin, Ya -Xia; ...

2014-10-27

Owing to the worldwide abundance and low-cost of Na, room-temperature Na-ion batteries are emerging as attractive energy storage systems for large-scale grids. Increasing the Na content in cathode material is one of the effective ways to achieve high energy density. Prussian blue and its analogues (PBAs) are promising Na-rich cathode materials since they can theoretically store two Na ions per formula. However, increasing the Na content in PBAs cathode materials is a big challenge in the current. Here we show that sodium iron hexacyanoferrate with high Na content could be obtained by simply controlling the reducing agent and reaction atmospheremore » during synthesis. The Na content can reach as high as 1.63 per formula, which is the highest value for sodium iron hexacyanoferrate. This Na-rich sodium iron hexacyanoferrate demonstrates a high specific capacity of 150 mA h g -1 and remarkable cycling performance with 90% capacity retention after 200 cycles. Furthermore, the Na intercalation/de-intercalation mechanism is systematically studied by in situ Raman, X-ray diffraction and X-ray absorption spectroscopy analysis for the first time. As a result, the Na-rich sodium iron hexacyanoferrate could function as a plenteous Na reservoir and has great potential as a cathode material toward practical Na-ion batteries.« less

Double Stent Assist Coiling of Ruptured Large Saccular Aneurysm in Proximal Basilar Artery Fenestration.

PubMed

Park, Woong Bae; Sung, Jae Hoon; Huh, Joon; Cho, Chul Bum; Yang, Seung Ho; Kim, Il Sup; Hong, Jae Taek; Lee, Sang Won

2015-09-01

Basilar artery fenestration is infrequent and even rarer in association with a large aneurysm. With proximity to brain stem and vital perforators, endovascular coiling can be considered first. If the large ruptured aneurysm with a wide neck originated from fenestra of the proximal basilar artery and the fenestration loop has branches of posterior circulation, therapeutic consideration should be thorough and fractionized. We report endovascular therapeutic details for a case of a ruptured large saccular aneurysm in proximal basilar artery fenestration.

Superconducting proximity effect in MBE grown Nb-InAs junctions

NASA Astrophysics Data System (ADS)

Kan, Carolyn; Xue, Chi; Law, Stephanie; Eckstein, James

2013-03-01

Several proposals for the realization of Majorana fermions rely on excellent quality proximity coupling between a superconductor and a high-mobility semiconductor. We examine the long-range proximity coupling between MBE-grown InAs and in situ grown superconducting overlayers by fabricating transport devices, and investigate the effect of substrate choice and growth conditions on the quality of the MBE InAs. GaAs is commonly available as a high quality insulating substrate. Overcoming its lattice mismatch with InAs using GaSb and AlSb layers results in locally smooth terraced surfaces, but global spiral dislocation structures also appear and have a negative impact on the InAs mobility. Growing InAs on homoepitaxial GaSb results in improved morphology and increases the mean free path. We compare the proximity effect in devices made both ways. This material is based upon work supported by the U.S. Department of Energy, Division of Materials Sciences under Award No. DE-FG02 07ER46453, through the Frederick Seitz Materials Research Laboratory at the University of Illinois at Urbana-Champaign.

Novel implant for peri-prosthetic proximal tibia fractures.

PubMed

Tran, Ton; Chen, Bernard K; Wu, Xinhua; Pun, Chung Lun

2018-03-01

Repair of peri-prosthetic proximal tibia fractures is very challenging in patients with a total knee replacement or arthroplasty. The tibial component of the knee implant severely restricts the fixation points of the tibial implant to repair peri-prosthetic fractures. A novel implant has been designed with an extended flange over the anterior of tibial condyle to provide additional points of fixation, overcoming limitations of existing generic locking plates used for proximal tibia fractures. Furthermore, the screws fixed through the extended flange provide additional support to prevent the problem of subsidence of tibial component of knee implant. The design methodology involved extraction of bone data from CT scans into a flexible CAD format, implant design and structural evaluation and optimisation using FEM as well as prototype development and manufacture by selective laser melting 3D printing technology with Ti6Al4 V powder. A prototype tibia implant was developed based on a patient-specific bone structure, which was regenerated from the CT images of patient's tibia. The design is described in detail and being applied to fit up to 80% of patients, for both left and right sides based on the average dimensions and shape of the bone structure from a wide range of CT images. A novel tibial implant has been developed to repair peri-prosthetic proximal tibia fractures which overcomes significant constraints from the tibial component of existing knee implant. Copyright © 2018 Elsevier Ltd. All rights reserved.

Long-range magnetic interactions and proximity effects in an amorphous exchange-spring magnet

DOE PAGES

Magnus, F.; Brooks-Bartlett, M. E.; Moubah, R.; ...

2016-06-13

Low-dimensional magnetic heterostructures are a key element of spintronics, where magnetic interactions between different materials often define the functionality of devices. Although some interlayer exchange coupling mechanisms are by now well established, the possibility of direct exchange coupling via proximity-induced magnetization through non-magnetic layers is typically ignored due to the presumed short range of such proximity effects. Here we show that magnetic order can be induced throughout a 40-nm-thick amorphous paramagnetic layer through proximity to ferromagnets, mediating both exchange-spring magnet behaviour and exchange bias. Furthermore, Monte Carlo simulations show that nearest-neighbour magnetic interactions fall short in describing the observed effectsmore » and long-range magnetic interactions are needed to capture the extent of the induced magnetization. Lastly, the results highlight the importance of considering the range of interactions in low-dimensional heterostructures and how magnetic proximity effects can be used to obtain new functionality.« less

Proximity of couples to parents: influences of gender, labor market, and family.

PubMed

Chan, Tak Wing; Ermisch, John

2015-04-01

We use household survey data from the UK to study how close middle-aged men and women in partnerships live to their parents and their partner's parents. We find a slight tendency for couples to live closer to the woman's parents than the man's. This tendency is more pronounced among couples in which neither partner has a college degree and in which there is a child. In other respects, proximity to parents is gender-neutral, with the two partners having equal influence on intergenerational proximity. Better-educated couples live farther from their parents. And although certain family characteristics matter, intergenerational proximity is primarily driven by factors affecting mobility over long distances, which are mainly associated with the labor market, as opposed to gender or family circumstances.

Space Network Time Distribution and Synchronization Protocol Development for Mars Proximity Link

NASA Technical Reports Server (NTRS)

Woo, Simon S.; Gao, Jay L.; Mills, David

2010-01-01

Time distribution and synchronization in deep space network are challenging due to long propagation delays, spacecraft movements, and relativistic effects. Further, the Network Time Protocol (NTP) designed for terrestrial networks may not work properly in space. In this work, we consider the time distribution protocol based on time message exchanges similar to Network Time Protocol (NTP). We present the Proximity-1 Space Link Interleaved Time Synchronization (PITS) algorithm that can work with the CCSDS Proximity-1 Space Data Link Protocol. The PITS algorithm provides faster time synchronization via two-way time transfer over proximity links, improves scalability as the number of spacecraft increase, lowers storage space requirement for collecting time samples, and is robust against packet loss and duplication which underlying protocol mechanisms provide.

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

Bioprinting of 3D Convoluted Renal Proximal Tubules on Perfusable Chips

PubMed Central

Homan, Kimberly A.; Kolesky, David B.; Skylar-Scott, Mark A.; Herrmann, Jessica; Obuobi, Humphrey; Moisan, Annie; Lewis, Jennifer A.

2016-01-01

Three-dimensional models of kidney tissue that recapitulate human responses are needed for drug screening, disease modeling, and, ultimately, kidney organ engineering. Here, we report a bioprinting method for creating 3D human renal proximal tubules in vitro that are fully embedded within an extracellular matrix and housed in perfusable tissue chips, allowing them to be maintained for greater than two months. Their convoluted tubular architecture is circumscribed by proximal tubule epithelial cells and actively perfused through the open lumen. These engineered 3D proximal tubules on chip exhibit significantly enhanced epithelial morphology and functional properties relative to the same cells grown on 2D controls with or without perfusion. Upon introducing the nephrotoxin, Cyclosporine A, the epithelial barrier is disrupted in a dose-dependent manner. Our bioprinting method provides a new route for programmably fabricating advanced human kidney tissue models on demand. PMID:27725720

Anatomy of the Pudendal Nerve and Other Neural Structures Around the Proximal Hamstring Origin in Males.

PubMed

Cvetanovich, Gregory L; Saltzman, Bryan M; Ukwuani, Gift; Frank, Rachel M; Verma, Nikhil N; Bush-Joseph, Charles A; Nho, Shane J

2018-03-29

To define the anatomy of the pudendal nerve in relationship to the proximal hamstring and other nearby neurological structures during proximal hamstring repair. Six fresh-frozen human cadaveric hemi-pelvises from male patients ages 64.0 ± 4.1 years were dissected in prone position with hips in 10° flexion to identify the relationship of proximal hamstring origin to surrounding neurologic structures including the pudendal nerve, sciatic nerve, and posterior femoral cutaneous nerve. Two independent observers used digital calipers to measure distances. The pudendal nerve emerged at the inferior border of the piriformis muscle 6.3 ± 1.4 cm from the superior aspect of the proximal hamstring origin. It passed the superior border of the sacrotuberous ligament 3.0 ± 0.6 cm from the superior aspect and 3.9 ± 0.7 cm from the medial aspect of the hamstring origin. It crossed the inferior border of the sacrotuberous ligament 3.0 ± 0.4 cm from the superior aspect and 2.7 ± 0.7 cm from the medial aspect of the proximal hamstring origin. The shortest distance from the hamstring origin to the pudendal nerve was 2.6 ± 0.5 cm from the superior aspect and 2.3 ± 0.8 cm from the medial aspect. The shortest distance from the hamstring origin to the pudendal nerve was located deep to the sacrotuberous ligament in all cadavers. The sciatic nerve was an average of 1.1 ± 0.1 cm lateral to the lateral aspect of the proximal hamstring origin. The posterior femoral cutaneous nerve was located between the hamstring origin and the sciatic nerve, 0.7 ± 0.2 cm lateral to the lateral aspect of the proximal hamstring origin. The proximal hamstring origin lies in close proximity to surrounding nerves, including the pudendal, sciatic, and posterior femoral cutaneous nerves. Knowledge that the pudendal nerve lies 2 to 3 cm superior and medial to the proximal hamstring origin may help to prevent iatrogenic damage during surgical dissection and retraction when performing proximal

Relationship Between Proximal Aorta Morphology and Progression Rate of Aortic Stenosis.

PubMed

Capoulade, Romain; Teoh, Jonathan G; Bartko, Philipp E; Teo, Eliza; Scholtz, Jan-Erik; Tastet, Lionel; Shen, Mylene; Mihos, Christos G; Park, Yong H; Garcia, Julio; Larose, Eric; Isselbacher, Eric M; Sundt, Thoralf M; MacGillivray, Thomas E; Melnitchouk, Serguei; Ghoshhajra, Brian B; Pibarot, Philippe; Hung, Judy

2018-05-01

The aim of this study was to examine the association between abnormal morphology of the proximal aorta and aortic stenosis (AS) progression rate. The main hypothesis was that morphologic changes of the proximal aorta, such as effacement of the sinotubular junction (STJ), result in increased biomechanical stresses and contribute to calcification and progression of AS. Between 2010 and 2012, 426 patients with mild to moderate AS were included in this study. Proximal aortic dimensions were measured at three different levels (i.e., sinus of Valsalva, STJ, and ascending aorta), and sinuses of Valsalva/STJ and ascending aorta/STJ ratios were used to determine degree of aortic deformity. AS progression rate was assessed by annualized increase in mean gradient (median follow-up time, 3.1 years; interquartile range, 2.6-3.9 years). The degree of aortic flow turbulence was examined in 18 matched patients with and without STJ effacement using cardiac magnetic resonance phase-contrast imaging. Patients' mean age was 71 ± 13 years, and 64% were men. Patients with low ratios had greater AS progression (P < .05). After comprehensive adjustment, sinuses of Valsalva/STJ (P = .025) and ascending aorta/STJ (P = .027) ratios were independently associated with greater AS progression rate. Compared with patients without STJ effacement, those with effacement of the STJ had higher degrees of aortic flow turbulence (24.4% vs 17.2%, P = .038). Effacement of the STJ is independently associated with greater AS progression, regardless of arterial hemodynamics, aortic valve phenotype, or baseline AS severity. Patients with abnormal proximal aortic geometry had disturbed aortic flow patterns. These findings suggest an interrelation between proximal aorta morphology and stenosis progression. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Akt recruits Dab2 to albumin endocytosis in the proximal tubule.

PubMed

Koral, Kelly; Li, Hui; Ganesh, Nandita; Birnbaum, Morris J; Hallows, Kenneth R; Erkan, Elif

2014-12-15

Proximal tubule epithelial cells have a highly sophisticated endocytic machinery to retrieve the albumin in the glomerular filtrate. The megalin-cubilin complex and the endocytic adaptor disabled-2 (Dab2) play a pivotal role in albumin endocytosis. We previously demonstrated that protein kinase B (Akt) regulates albumin endocytosis in the proximal tubule through an interaction with Dab2. Here, we examined the nature of Akt-Dab2 interaction. The pleckstrin homology (PH) and catalytic domains (CD) of Akt interacted with the proline-rich domain (PRD) of Dab2 based on yeast-two hybrid (Y2H) experiments. Pull-down experiments utilizing the truncated constructs of Dab2 demonstrated that the initial 11 amino acids of Dab2-PRD were sufficient to mediate the interaction between Akt and Dab2. Endocytosis experiments utilizing Akt1- and Akt2-silencing RNA revealed that both Akt1 and Akt2 mediate albumin endocytosis in proximal tubule epithelial cells; therefore, Akt1 and Akt2 may play a compensatory role in albumin endocytosis. Furthermore, both Akt isoforms phosphorylated Dab2 at Ser residues 448 and 449. Ser-to-Ala mutations of these Dab2 residues inhibited albumin endocytosis and resulted in a shift in location of Dab2 from the peripheral to the perinuclear area, suggesting the physiological relevance of these phosphorylation sites in albumin endocytosis. We conclude that both Akt1 and Akt2 are involved in albumin endocytosis, and phosphorylation of Dab2 by Akt induces albumin endocytosis in proximal tubule epithelial cells. Further delineation of how Akt affects expression/phosphorylation of endocytic adaptors and receptors will enhance our understanding of the molecular network triggered by albumin overload in the proximal tubule. Copyright © 2014 the American Physiological Society.

Treatment of proximal humerus fractures with locking plates: a systematic review.

PubMed

Thanasas, Christos; Kontakis, George; Angoules, Antonios; Limb, David; Giannoudis, Peter

2009-01-01

Locking plates with special configuration for the anatomic region of the proximal humerus have been introduced recently to address the difficulties of stabilizing proximal humeral fractures. The purpose of this study was to carry out a systematic review of the literature on the efficacy and early to medium term functional results of locking plates for stabilization of proximal humeral fractures. Using the PubMed database, a systematic review of the English and German literature was carried out in order to assess the efficacy and complications related to the use of these plates and the patients' functional outcome, using the key words "locking plates proximal humeral fractures," "angular stability plates proximal humeral fractures," "PHILOS plate," and "LPHP plate." Our criteria for eligibility were clinical studies with more than ten cases followed-up, adult patients, and adequate data provided at least in terms of implant related complications. Articles written in English and German language were included. Exclusion criteria were: studies dealing exclusively with 2-part fractures (since this category has a more favorable outcome); experimental studies; case reports; and, literature other than English or German. Each one of the articles was evaluated for quality of the study using the Structured Effectiveness Quality Evaluation Scale (SEQES). Twelve studies including 791 patients met the inclusion criteria. Patients in these studies continued to improve up to one year, achieving a mean Constant score of 74.3. The incidence of the reported complications was: avascular necrosis 7.9%, screw cut-out 11.6% and re-operation rate 13.7%. The high incidence of cut-out may be secondary to the rigidity of the implant in combination with medial inadequate support, in cases compromised by severe underlying osteoporotic bone. Definition of indications for the use of locking plates and attention on technical aspects of applying them would help optimization of the results

Validation of a smartphone app to map social networks of proximity

PubMed Central

Larsen, Mark E.; Townsend, Samuel; Christensen, Helen

2017-01-01

Social network analysis is a prominent approach to investigate interpersonal relationships. Most studies use self-report data to quantify the connections between participants and construct social networks. In recent years smartphones have been used as an alternative to map networks by assessing the proximity between participants based on Bluetooth and GPS data. While most studies have handed out specially programmed smartphones to study participants, we developed an application for iOS and Android to collect Bluetooth data from participants’ own smartphones. In this study, we compared the networks estimated with the smartphone app to those obtained from sociometric badges and self-report data. Participants (n = 21) installed the app on their phone and wore a sociometric badge during office hours. Proximity data was collected for 4 weeks. A contingency table revealed a significant association between proximity data (ϕ = 0.17, p<0.0001), but the marginal odds were higher for the app (8.6%) than for the badges (1.3%), indicating that dyads were more often detected by the app. We then compared the networks that were estimated using the proximity and self-report data. All three networks were significantly correlated, although the correlation with self-reported data was lower for the app (ρ = 0.25) than for badges (ρ = 0.67). The scanning rates of the app varied considerably between devices and was lower on iOS than on Android. The association between the app and the badges increased when the network was estimated between participants whose app recorded more regularly. These findings suggest that the accuracy of proximity networks can be further improved by reducing missing data and restricting the interpersonal distance at which interactions are detected. PMID:29261782

Bone remodeling after MR imaging-guided high-intensity focused ultrasound ablation: evaluation with MR imaging, CT, Na(18)F-PET, and histopathologic examination in a swine model.

PubMed

Bucknor, Matthew D; Rieke, Viola; Seo, Youngho; Horvai, Andrew E; Hawkins, Randall A; Majumdar, Sharmila; Link, Thomas M; Saeed, Maythem

2015-02-01

To serially monitor bone remodeling in the swine femur after magnetic resonance (MR) imaging-guided high-intensity focused ultrasound (HIFU) ablation with MR imaging, computed tomography (CT), sodium fluorine 18 (Na(18)F)-positron emission tomography (PET), and histopathologic examination, as a function of sonication energy. Experimental procedures received approval from the local institutional animal care and use committee. MR imaging-guided HIFU was used to create distal and proximal ablations in the right femurs of eight pigs. The energy used at the distal target was higher (mean, 419 J; range, 390-440 J) than that used at the proximal target (mean, 324 J; range, 300-360 J). Imaging was performed before and after ablation with 3.0-T MR imaging and 64-section CT. Animals were reevaluated at 3 and 6 weeks with MR imaging (n = 8), CT (n = 8), Na(18)F-PET (n = 4), and histopathologic examination (n = 4). Three-dimensional ablation lengths were measured on contrast material-enhanced MR images, and bone remodeling in the cortex was measured on CT images. Ablation sizes at MR imaging 3 and 6 weeks after MR imaging-guided HIFU ablation were similar between proximal (low-energy) and distal (high-energy) lesions (average, 8.7 × 21.9 × 16.4 mm). However, distal ablation lesions (n = 8) demonstrated evidence of subperiosteal new bone formation at CT, with a subtle focus of new ossification at 3 weeks and a larger focus of ossification at 6 weeks. New bone formation was associated with increased uptake at Na(18)F-PET in three of four animals; this was confirmed at histopathologic examination in four of four animals. MR imaging-guided HIFU ablation of bone may result in progressive remodeling, with both subcortical necrosis and subperiosteal new bone formation. This may be related to the use of high energies. MR imaging, CT, and PET are suitable noninvasive techniques to monitor bone remodeling after MR imaging-guided HIFU ablation. © RSNA, 2014.

Inducing Strong Superconductivity in WTe2 by a Proximity Effect.

PubMed

Huang, Ce; Narayan, Awadhesh; Zhang, Enze; Liu, Yanwen; Yan, Xiao; Wang, Jiaxiang; Zhang, Cheng; Wang, Weiyi; Zhou, Tong; Yi, Changjiang; Liu, Shanshan; Ling, Jiwei; Zhang, Huiqin; Liu, Ran; Sankar, Raman; Chou, Fangcheng; Wang, Yihua; Shi, Youguo; Law, Kam Tuen; Sanvito, Stefano; Zhou, Peng; Han, Zheng; Xiu, Faxian

2018-06-21

The search for proximity-induced superconductivity in topological materials has generated widespread interest in the condensed matter physics community. The superconducting states inheriting nontrivial topology at interfaces are expected to exhibit exotic phenomena such as topological superconductivity and Majorana zero modes, which hold promise for applications in quantum computation. However, a practical realization of such hybrid structures based on topological semimetals and superconductors has hitherto been limited. Here, we report the strong proximity-induced superconductivity in type-II Weyl semimetal WTe 2 , in a van der Waals hybrid structure obtained by mechanically transferring NbSe 2 onto various thicknesses of WTe 2 . When the WTe 2 thickness ( t WTe 2 ) reaches 21 nm, the superconducting transition occurs around the critical temperature ( T c ) of NbSe 2 with a gap amplitude (Δ p ) of 0.38 meV and an unexpected ultralong proximity length ( l p ) up to 7 μm. With the thicker 42 nm WTe 2 layer, however, the proximity effect yields T c ≈ 1.2 K, Δ p = 0.07 meV, and a short l p of less than 1 μm. Our theoretical calculations, based on the Bogoliubov-de Gennes equations in the clean limit, predict that the induced superconducting gap is a sizable fraction of the NbSe 2 superconducting one when t WTe 2 is less than 30 nm and then decreases quickly as t WTe 2 increases. This agrees qualitatively well with the experiments. Such observations form a basis in the search for superconducting phases in topological semimetals.

The relationship between physical activity facility proximity and leisure-time physical activity in persons with spinal cord injury.

PubMed

Arbour, Kelly P; Martin Ginis, Kathleen A

2009-07-01

Within the general able-bodied population, proximity of one's home to physical activity facilities is modestly associated with physical activity behavior. Currently, no research has examined whether facility proximity is related to physical activity among persons living with disabilities. To examine (1) the level of agreement between perceived and actual proximity to accessible physical activity facilities and (2) the relationship between facility proximity (perceived and actual) and leisure-time physical activity (LTPA) among persons with spinal cord injury (SCI). It was hypothesized that (1) perceived and actual proximity measures would exhibit low agreement and (2) a small, positive relationship would emerge between proximity (perceived and actual) and LTPA. Data from 50 Ontario residents living with SCI (70% male; 52% tetraplegia) were collected for proximity and LTPA. Perceived facility proximity was determined by a self-report "YES" versus "NO" presence measure, while actual facility proximity was assessed using Geographical Information Systems. An SCI-specific instrument, the PARA-SCI, was used to measure LTPA. Low agreement levels were found between perceived and actual proximity. LTPA status (active versus inactive) was shown to moderate the relationship, with higher agreement levels found for participants who reported engaging in mild or heavy LTPA versus their inactive counterparts, but only for the 30-minute wheeling boundary. Contrary to hypothesis, people living within a 30-minute wheel from an accessible facility were less likely to engage in heavy LTPA than were people who did not have an accessible facility located within a 30-minute wheel. No significant associations were found between LTPA and perceived proximity. Living in close proximity to a facility that provides accessible programming and equipment does not necessarily translate into greater physical activity behavior.

Transfer of Motor Learning Is More Pronounced in Proximal Compared to Distal Effectors in Upper Extremities

PubMed Central

Aune, Tore K.; Aune, Morten A.; Ingvaldsen, Rolf P.; Vereijken, Beatrix

2017-01-01

The current experiment investigated generalizability of motor learning in proximal versus distal effectors in upper extremities. Twenty-eight participants were divided into three groups: training proximal effectors, training distal effectors, and no training control group (CG). Performance was tested pre- and post-training for specific learning and three learning transfer conditions: (1) bilateral learning transfer between homologous effectors, (2) lateral learning transfer between non-homologous effectors, and (3) bilateral learning transfer between non-homologous effectors. With respect to specific learning, both training groups showed significant, similar improvement for the trained proximal and distal effectors, respectively. In addition, there was significant learning transfer to all three transfer conditions, except for bilateral learning transfer between non-homologous effectors for the distal training group. Interestingly, the proximal training group showed significantly larger learning transfer to other effectors compared to the distal training group. The CG did not show significant improvements from pre- to post-test. These results show that learning is partly effector independent and generalizable to different effectors, even though transfer is suboptimal compared to specific learning. Furthermore, there is a proximal-distal gradient in generalizability, in that learning transfer from trained proximal effectors is larger than from trained distal effectors, which is consistent with neuroanatomical differences in activation of proximal and distal muscles. PMID:28943857

Associations between Body Mass Index and Park Proximity, Size, Cleanliness and Recreational Facilities

PubMed Central

Quinn, James; Lovasi, Gina; Bader, Michael; Yousefzadeh, Paulette; Weiss, Christopher; Neckerman, Kathryn

2013-01-01

Purpose To determine whether body mass index (BMI) is associated with proximity to neighborhood parks, the size of the parks, their cleanliness and the availability of recreational facilities in the parks. Design Cross-sectional. Setting New York City. Subjects 13,102 adults (median age 45 years, 36% male) recruited from 2000–2002. Measures Anthropometric and socio-demographic data from study subjects were linked to Department of Parks & Recreation data on park space, cleanliness, and facilities. Neighborhood level socio-demographic and park proximity metrics were created for half-mile radius circular buffers around each subject’s residence. Proximity to park space was measured as the proportion of the subject’s neighborhood buffer area that was total park space, large park space (a park > 6 acres) and small park space (a park <=6 acres). Analysis Hierarchical linear models were used to determine whether neighborhood park metrics were associated with BMI. Results Higher proximity to large park space was significantly associated with lower BMI (beta = −1.69 95% CI = −2.76, −0.63). Across the population distribution of proximity to large park space, compared to subjects living in neighborhoods at the 10th percentile of the distribution, the covariate adjusted average BMI was estimated to be 0.35 kg/m2 lower for those living in neighborhoods at the 90th percentile. The proportion of neighborhood area that was small park space was not associated with BMI, nor was park cleanliness or the availability of recreational facilities. Conclusions Neighborhood proximity to large park spaces is modestly associated with lower BMI in a diverse urban population. PMID:23448416

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…

Proximity under Threat: The Role of Physical Distance in Intergroup Relations

PubMed Central

Wohl, Michael J. A.; Van Bavel, Jay J.

2016-01-01

Throughout human history, social groups have invested immense amounts of wealth and time to keep threatening out-groups at a distance. In the current research, we explored the relationship between intergroup threat, physical distance, and discrimination. Specifically, we examined how intergroup threat alters estimates of physical distance to out-groups and how physical proximity affects intergroup relations. Previous research has found that people judge threatening out-groups as physically close. In Studies 1 and 2, we examined ways to attenuate this bias. In Study 1 a secure (vs. permeable) US-Mexico border reduced the estimated proximity to Mexico City among Americans who felt threatened by Mexican immigration. In Study 2, intergroup apologies reduced estimates of physical proximity to a threatening cross-town rival university, but only among participants with cross-group friendships. In Study 3, New York Yankees fans who received an experimental induction of physical proximity to a threatening out-group (Boston Red Sox) had a stronger relationship between their collective identification with the New York Yankees and support for discriminatory policies toward members of the out-group (Red Sox fans) as well as how far they chose to sit from out-group members (Red Sox fans). Together, these studies suggest that intergroup threat alters judgment of physical properties, which has important implications for intergroup relations. PMID:27467267

Hydrogen-fluorine exchange in NaBH4-NaBF4.

PubMed

Rude, L H; Filsø, U; D'Anna, V; Spyratou, A; Richter, B; Hino, S; Zavorotynska, O; Baricco, M; Sørby, M H; Hauback, B C; Hagemann, H; Besenbacher, F; Skibsted, J; Jensen, T R

2013-11-07

Hydrogen-fluorine exchange in the NaBH4-NaBF4 system is investigated using a range of experimental methods combined with DFT calculations and a possible mechanism for the reactions is proposed. Fluorine substitution is observed using in situ synchrotron radiation powder X-ray diffraction (SR-PXD) as a new Rock salt type compound with idealized composition NaBF2H2 in the temperature range T = 200 to 215 °C. Combined use of solid-state (19)F MAS NMR, FT-IR and DFT calculations supports the formation of a BF2H2(-) complex ion, reproducing the observation of a (19)F chemical shift at -144.2 ppm, which is different from that of NaBF4 at -159.2 ppm, along with the new absorption bands observed in the IR spectra. After further heating, the fluorine substituted compound becomes X-ray amorphous and decomposes to NaF at ~310 °C. This work shows that fluorine-substituted borohydrides tend to decompose to more stable compounds, e.g. NaF and BF3 or amorphous products such as closo-boranes, e.g. Na2B12H12. The NaBH4-NaBF4 composite decomposes at lower temperatures (300 °C) compared to NaBH4 (476 °C), as observed by thermogravimetric analysis. NaBH4-NaBF4 (1:0.5) preserves 30% of the hydrogen storage capacity after three hydrogen release and uptake cycles compared to 8% for NaBH4 as measured using Sievert's method under identical conditions, but more than 50% using prolonged hydrogen absorption time. The reversible hydrogen storage capacity tends to decrease possibly due to the formation of NaF and Na2B12H12. On the other hand, the additive sodium fluoride appears to facilitate hydrogen uptake, prevent foaming, phase segregation and loss of material from the sample container for samples of NaBH4-NaF.

The use of cues to convergence and accommodation in naïve, uninstructed participants

PubMed Central

Horwood, Anna M; Riddell, Patricia M

2015-01-01

A remote haploscopic video refractor was used to assess vergence and accommodation responses in a group of 32 emmetropic, orthophoric, symptom free, young adults naïve to vision experiments in a minimally instructed setting. Picture targets were presented at four positions between 2m and 33cm. Blur, disparity and looming cues were presented in combination or separately to asses their contributions to the total near response in a within-subjects design. Response gain for both vergence and accommodation reduced markedly whenever disparity was excluded, with much smaller effects when blur and proximity were excluded. Despite the clinical homogeneity of the participant group there were also some individual differences. PMID:18538815

Proximate and polyphenolic characterization of cranberry pomace.

PubMed

White, Brittany L; Howard, Luke R; Prior, Ronald L

2010-04-14

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, dietary fiber, and ash. Other carbohydrates were determined by the difference method. Polyphenolic compounds were identified and quantified by HPLC-ESI-MS. The composition of dried cranberry pomace was 4.5% moisture, 2.2% protein, 12.0% fat, 65.5% insoluble fiber, 5.7% soluble fiber, 8.4% other carbohydrates, 1.1% ash, and 0.6% total polyphenolics. It contained six anthocyanins (111.5 mg/100 g of DW) including derivatives of cyanidin and peonidin. Thirteen flavonols were identified (358.4 mg/100 g of DW), and the aglycones myricetin (55.6 mg/100 g of DW) and quercetin (146.2 mg/100 g of DW) were the most prominent. Procyanidins with degrees of polymerization (DP) of 1-6 were identified (167.3 mg/100 g of DW), the most abundant being an A-type of DP2 (82.6 mg/100 g of DW).

The quantitative role of flexor sheath incision in correcting Dupuytren proximal interphalangeal joint contractures.

PubMed

Blazar, P E; Floyd, E W; Earp, B E

2016-07-01

Controversy exists regarding intra-operative treatment of residual proximal interphalangeal joint contractures after Dupuytren's fasciectomy. We test the hypothesis that a simple release of the digital flexor sheath can correct residual fixed flexion contracture after subtotal fasciectomy. We prospectively enrolled 19 patients (22 digits) with Dupuytren's contracture of the proximal interphalangeal joint. The average pre-operative extension deficit of the proximal interphalangeal joints was 58° (range 30-90). The flexion contracture of the joint was corrected to an average of 28° after fasciectomy. In most digits (20 of 21), subsequent incision of the flexor sheath further corrected the contracture by an average of 23°, resulting in correction to an average flexion contracture of 4.7° (range 0-40). Our results support that contracture of the tendon sheath is a contributor to Dupuytren's contracture of the joint and that sheath release is a simple, low morbidity addition to correct Dupuytren's contractures of the proximal interphalangeal joint. Additional release of the proximal interphalangeal joint after fasciectomy, after release of the flexor sheath, is not necessary in many patients. IV (Case Series, Therapeutic). © The Author(s) 2015.

Dendritic Na+ spikes enable cortical input to drive action potential output from hippocampal CA2 pyramidal neurons

PubMed Central

Sun, Qian; Srinivas, Kalyan V; Sotayo, Alaba; Siegelbaum, Steven A

2014-01-01

Synaptic inputs from different brain areas are often targeted to distinct regions of neuronal dendritic arbors. Inputs to proximal dendrites usually produce large somatic EPSPs that efficiently trigger action potential (AP) output, whereas inputs to distal dendrites are greatly attenuated and may largely modulate AP output. In contrast to most other cortical and hippocampal neurons, hippocampal CA2 pyramidal neurons show unusually strong excitation by their distal dendritic inputs from entorhinal cortex (EC). In this study, we demonstrate that the ability of these EC inputs to drive CA2 AP output requires the firing of local dendritic Na+ spikes. Furthermore, we find that CA2 dendritic geometry contributes to the efficient coupling of dendritic Na+ spikes to AP output. These results provide a striking example of how dendritic spikes enable direct cortical inputs to overcome unfavorable distal synaptic locale to trigger axonal AP output and thereby enable efficient cortico-hippocampal information flow. DOI: http://dx.doi.org/10.7554/eLife.04551.001 PMID:25390033

Management of proximal humeral fractures in the nineteenth century: an historical review of preradiographic sources.

PubMed

Brorson, Stig

2011-04-01

The diagnosis and treatment of fractures of the proximal humerus have troubled patients and medical practitioners since antiquity. Preradiographic diagnosis relied on surface anatomy, pain localization, crepitus, and impaired function. During the nineteenth century, a more thorough understanding of the pathoanatomy and pathophysiology of proximal humeral fractures was obtained, and new methods of reduction and bandaging were developed. I reviewed nineteenth-century principles of (1) diagnosis, (2) classification, (3) reduction, (4) bandaging, and (5) concepts of displacement in fractures of the proximal humerus. A narrative review of nineteenth-century surgical texts is presented. Sources were identified by searching bibliographic databases, orthopaedic sourcebooks, textbooks in medical history, and a subsequent hand search. Substantial progress in understanding fractures of the proximal humerus is found in nineteenth-century textbooks. A rational approach to understanding fractures of the proximal humerus was made possible by an appreciation of the underlying functional anatomy and subsequent pathoanatomy. Thus, new principles of diagnosis, pathoanatomic classifications, modified methods of reduction, functional bandaging, and advanced concepts of displacement were proposed, challenging the classic management adhered to for more than 2000 years. The principles for modern pathoanatomic and pathophysiologic understanding of proximal humeral fractures and the principles for classification, nonsurgical treatment, and bandaging were established in the preradiographic era.

Novel Biosensor of Membrane Protein Proximity Based on Fluorogen Activated Proteins.

PubMed

Vasilev, Kalin V; Gallo, Eugenio; Shank, Nathaniel; Jarvik, Jonathan W

2016-01-01

We describe a novel biosensor system for reporting proximity between cell surface proteins in live cultured cells. The biosensor takes advantage of recently developed fluorogen-activating proteins (FAPs) that display fluorescence only when bound to otherwise-nonfluorescent fluorogen molecules. To demonstrate feasibility for the approach, two recombinant rapamycin-binding proteins were expressed as single-pass plasma membrane proteins in HeLa cells; one of the proteins (scAvd- FRB) carried an extracellular avidin tag; the other (HL1-TO1-FKBP) carried an extracellular FAP. Cells were incubated with a membrane-impermeable bivalent ligand (biotin-PEG2000-DIR) consisting of biotin joined to a dimethyl-indole red (DIR) fluorogen by a polyethylene glycol linker, thus tethering the fluorogen to the scAvd-FRB fusion protein. Addition of rapamycin, which promotes FKBP-FRB dimerization and thereby brings the FAP in close proximity to the tethered fluorogen, led to a significant increase in DIR fluorescence. We call the new proximity assay TEFLA, for tethered fluorogen assay.

Ontogeny and Sexual Differences in Swimming Proximity to Conspecifics in Response to Visual Cues in Medaka Fish.

PubMed

Isoe, Yasuko; Konagaya, Yumi; Yokoi, Saori; Kubo, Takeo; Takeuchi, Hideaki

2016-06-01

Adult medaka fish (Oryzias latipes) exhibit complex social behaviors that depend mainly on visual cues from conspecifics. The ontogeny of visually-mediated social behaviors from larval/juvenile to adult medaka fish, however, is unknown. In the present study, we established a simple behavioral paradigm to evaluate the swimming proximity to conspecifics based on visual cues in an inter-individual interaction of two medaka fish throughout life. When two fish were placed separately in a cylindrical tank with a concentric transparent wall, the two fish maintained close proximity to each other. A normal fish inside the tank maintained proximity to an optic nerve-cut fish outside of the tank, while the converse was not true. This behavioral paradigm enabled us to quantify visually-induced motivation of a single fish inside the tank. The proximity was detected from larval/juvenile to adult fish. Larval fish, however, maintained close proximity not only to conspecifics, but also to heterospecifics. As the growth stage increased, the degree of proximity to heterospecifics decreased, suggesting that shoaling preferences toward conspecifics and/or visual ability to recognize conspecifics is refined and established according to the growth stage. Furthermore, the proximity of adult female fish was affected by their reproductive status and social familiarity. Only before spawning, adult females maintained closer proximity to familiar males rather than to unfamiliar males, suggesting that proximity was affected by familiarity in a female-specific manner. This simple behavioral paradigm will contribute to our understanding of the neural basis of the development of visually-mediated social behavior using medaka fish.

Hypospadias: Are we as good as we think when we correct proximal hypospadias?

PubMed

Long, C J; Canning, D A

2016-08-01

Hypospadias surgery is a humbling art form. Although outcomes with distal hypospadias are favorable, recent publications have suggested that the complication rates are much higher than previously anticipated for proximal hypospadias. The present review examined the literature concerning proximal hypospadias, to explore some of the inadequacies and identify some of the reasons behind these shortfalls in the reported data. A systematic review of the published literature was conducted using keywords relevant to proximal hypospadias and long-term outcomes. The literature for hypospadias was reviewed, and outcomes for distal vs proximal variants were compared. The quality of the literature for proximal hypospadias was examined, and the shortcomings that led to underreporting of the surgical outcomes were identified. Special focus was on the lack of standardized documentation, the subsequent inability to objectify the severity of the phenotype, and the underestimation of complications due to lack of long-term follow-up. There was also a great deal of variability in the utilized techniques, and the literature was filled with small case series from single institutions. To enable scientific assessment of outcomes, it is proposed that the following be implemented: acceptance and incorporation of standardized phenotype assessment scores in the pre-operative period, objective intraoperative hypospadias characterization, and postoperative score assessment. Treatment of proximal hypospadias is much less successful than the distal variant. A specialty wide commitment to standardize the hypospadias language is required to make advancement in surgical outcomes. Boys need to be followed through puberty into adulthood, and honest reporting of outcomes must be discussed so that surgical techniques for this complicated disease process can be advanced. Copyright © 2016 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Impairment of the proximal to distal tonic gradient in the human diabetic stomach.

PubMed

Min, Y W; Hong, Y S; Ko, E-J; Lee, J Y; Min, B-H; Sohn, T S; Kim, J J; Rhee, P-L

2014-02-01

Little has been known about the contractile characteristics of diabetic stomach. We investigated spontaneous contractions and responses to acetylcholine in the gastric muscle in diabetic patients and non-diabetic control subjects according to the region of stomach. Gastric specimens were obtained from 26 diabetics and 55 controls who underwent gastrectomy at Samsung Medical Center between February 2008 and November 2011. Isometric force measurements were performed using circular muscle strips from the different regions of stomach under basal condition and in response to acetylcholine. Basal tone of control was higher in the proximal stomach than in the distal (0.63 g vs 0.46 g, p = 0.027). However, in diabetics, basal tone was not significantly different between the proximal and distal stomach (0.75 g vs 0.62 g, p = 0.32). The distal stomach of diabetics had higher basal tone and lower frequency than that of control (0.62 g vs 0.46 g, p = 0.049 and 4.0/min vs 4.9/min, p = 0.049, respectively). After exposure to acetylcholine, dose-dependent increases of basal tone, peak, and area under the curve (AUC) were noticed in both proximal and distal stomach of the two groups. In the proximal stomach, however, the dose-dependent increase of basal tone and AUC was less prominent in diabetics than in control. On the contrary to control, the proximal to distal tonic gradient was not observed in diabetic stomach. Diabetic stomach also had lower frequency of spontaneous contraction in the distal stomach and less acetylcholine-induced positive inotropic effect in the proximal stomach than control. © 2013 John Wiley & Sons Ltd.

The Effect of Ethnolinguistic Differences on Proximity between Cantonese and Mandarin Speaking Children.

ERIC Educational Resources Information Center

Leung, Lanna Oi-Ling; Lewis, George F.

1999-01-01

Examined effects of ethnolinguistic differences on social proximity between Cantonese- and Mandarin-speaking Chinese children in a day care center. Found that each group of children was more likely to be in closer proximity to children speaking their own language than to children speaking the other language during free choice floor- and group-time…

Simulation on the internal structure of three-dimensional proximal tibia under different mechanical environments.

PubMed

Fang, Juan; Gong, He; Kong, Lingyan; Zhu, Dong

2013-12-20

Bone can adjust its morphological structure to adapt to the changes of mechanical environment, i.e. the bone structure change is related to mechanical loading. This implies that osteoarthritis may be closely associated with knee joint deformity. The purposes of this paper were to simulate the internal bone mineral density (BMD) change in three-dimensional (3D) proximal tibia under different mechanical environments, as well as to explore the relationship between mechanical environment and bone morphological abnormity. The right proximal tibia was scanned with CT to reconstruct a 3D proximal tibia model in MIMICS, then it was imported to finite element software ANSYS to establish 3D finite element model. The internal structure of 3D proximal tibia of young normal people was simulated using quantitative bone remodeling theory in combination with finite element method, then based on the changing pattern of joint contact force on the tibial plateau in valgus knees, the mechanical loading was changed, and the simulated normal tibia structure was used as initial structure to simulate the internal structure of 3D proximal tibia for old people with 6° valgus deformity. Four regions of interest (ROIs) were selected in the proximal tibia to quantitatively analyze BMD and compare with the clinical measurements. The simulation results showed that the BMD distribution in 3D proximal tibia was consistent with clinical measurements in normal knees and that in valgus knees was consistent with the measurement of patients with osteoarthritis in clinics. It is shown that the change of mechanical environment is the main cause for the change of subchondral bone structure, and being under abnormal mechanical environment for a long time may lead to osteoarthritis. Besides, the simulation method adopted in this paper can more accurately simulate the internal structure of 3D proximal tibia under different mechanical environments. It helps to better understand the mechanism of

Simulation on the internal structure of three-dimensional proximal tibia under different mechanical environments

PubMed Central

2013-01-01

Background Bone can adjust its morphological structure to adapt to the changes of mechanical environment, i.e. the bone structure change is related to mechanical loading. This implies that osteoarthritis may be closely associated with knee joint deformity. The purposes of this paper were to simulate the internal bone mineral density (BMD) change in three-dimensional (3D) proximal tibia under different mechanical environments, as well as to explore the relationship between mechanical environment and bone morphological abnormity. Methods The right proximal tibia was scanned with CT to reconstruct a 3D proximal tibia model in MIMICS, then it was imported to finite element software ANSYS to establish 3D finite element model. The internal structure of 3D proximal tibia of young normal people was simulated using quantitative bone remodeling theory in combination with finite element method, then based on the changing pattern of joint contact force on the tibial plateau in valgus knees, the mechanical loading was changed, and the simulated normal tibia structure was used as initial structure to simulate the internal structure of 3D proximal tibia for old people with 6° valgus deformity. Four regions of interest (ROIs) were selected in the proximal tibia to quantitatively analyze BMD and compare with the clinical measurements. Results The simulation results showed that the BMD distribution in 3D proximal tibia was consistent with clinical measurements in normal knees and that in valgus knees was consistent with the measurement of patients with osteoarthritis in clinics. Conclusions It is shown that the change of mechanical environment is the main cause for the change of subchondral bone structure, and being under abnormal mechanical environment for a long time may lead to osteoarthritis. Besides, the simulation method adopted in this paper can more accurately simulate the internal structure of 3D proximal tibia under different mechanical environments. It helps to better

Transverse Stress Fracture of the Proximal Patella: A Case Report.

PubMed

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

2016-02-01

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.

76 FR 63238 - Proximity Detection Systems for Continuous Mining Machines in Underground Coal Mines

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-12

... Detection Systems for Continuous Mining Machines in Underground Coal Mines AGENCY: Mine Safety and Health... Agency's proposed rule addressing Proximity Detection Systems for Continuous Mining Machines in... proposed rule for Proximity Detection Systems on Continuous Mining Machines in Underground Coal Mines. Due...

75 FR 33198 - Co-Location/Proximity Hosting Services

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-11

... Execution Facilities (DTEFs), and Exempt Commercial Markets (ECMs) that list significant price discovery..., DTEFs, and ECMs with SPDCs, that offer co-location and/ or proximity hosting services, to disclose.... Finally, the Proposal would require DCMs, DTEFs, and ECMs with SPDCs, that approve third-parties to...

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. 2008 APA

The anterolateral acromial approach for fractures of the proximal humerus.

PubMed

Gardner, Michael J; Boraiah, Sreevathsa; Helfet, David L; Lorich, Dean G

2008-02-01

Displaced and unstable fractures of the proximal humerus are notoriously difficult to manage. Successful surgical treatment requires finding the appropriate balance between adequate exposure for reduction and rigid fixation and minimizing soft tissue dissection. The anterolateral acromial approach was developed to allow less invasive treatment of proximal humerus fractures. The plane of the avascular anterior deltoid raphe is utilized, and the axillary nerve is identified and protected. Anterior dissection near the critical blood supply is avoided, substantial muscle retraction is minimized, and the lateral plating zone is directly accessed. Over a 4-year period, 52 patients with acute displaced fractures of the proximal humerus were treated with the anterolateral acromial approach and either a locking plate or an intramedullary nail. Twenty-three patients were evaluated clinically at a minimum follow-up of 1 year (average, 28 months) by clinical examination for range of motion and nerve function and a QuickDASH score. There were no axillary nerve deficits postoperatively related to the approach, and the average QuickDASH score was 25.2 (0, best; 100, worst). This approach allowed direct access to the lateral fracture planes for fracture reduction and plate placement or safe nail and interlocking screw placement.

Na/K pump inactivation, subsarcolemmal Na measurements, and cytoplasmic ion turnover kinetics contradict restricted Na spaces in murine cardiac myocytes

PubMed Central

Lu, Fang-Min

2017-01-01

Decades ago, it was proposed that Na transport in cardiac myocytes is modulated by large changes in cytoplasmic Na concentration within restricted subsarcolemmal spaces. Here, we probe this hypothesis for Na/K pumps by generating constitutive transsarcolemmal Na flux with the Na channel opener veratridine in whole-cell patch-clamp recordings. Using 25 mM Na in the patch pipette, pump currents decay strongly during continuous activation by extracellular K (τ, ∼2 s). In contradiction to depletion hypotheses, the decay becomes stronger when pump currents are decreased by hyperpolarization. Na channel currents are nearly unchanged by pump activity in these conditions, and conversely, continuous Na currents up to 0.5 nA in magnitude have negligible effects on pump currents. These outcomes are even more pronounced using 50 mM Li as a cytoplasmic Na congener. Thus, the Na/K pump current decay reflects mostly an inactivation mechanism that immobilizes Na/K pump charge movements, not cytoplasmic Na depletion. When channel currents are increased beyond 1 nA, models with unrestricted subsarcolemmal diffusion accurately predict current decay (τ ∼15 s) and reversal potential shifts observed for Na, Li, and K currents through Na channels opened by veratridine, as well as for Na, K, Cs, Li, and Cl currents recorded in nystatin-permeabilized myocytes. Ion concentrations in the pipette tip (i.e., access conductance) track without appreciable delay the current changes caused by sarcolemmal ion flux. Importantly, cytoplasmic mixing volumes, calculated from current decay kinetics, increase and decrease as expected with osmolarity changes (τ >30 s). Na/K pump current run-down over 20 min reflects a failure of pumps to recover from inactivation. Simulations reveal that pump inactivation coupled with Na-activated recovery enhances the rapidity and effectivity of Na homeostasis in cardiac myocytes. In conclusion, an autoregulatory mechanism enhances cardiac Na/K pump activity when

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

PubMed Central

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

2016-01-01

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. PMID:27009341

[RESEARCH PROGRESS OF BIOMECHANICS OF PROXIMAL ROW CARPAL INSTABILITY].

PubMed

Guo, Jinhai; Huang, Fuguo

2015-01-01

To review the research progress of the biomechanics of proximal row carpal instability (IPRC). The related literature concerning IPRC was extensively reviewed. The biomechanical mechanism of the surrounding soft tissue in maintaining the stability of the proximal row carpal (PRC) was analyzed, and the methods to repair or reconstruct the stability and function of the PRC were summarized from two aspects including basic biomechanics and clinical biomechanics. The muscles and ligaments of the PRC are critical to its stability. Most scholars have reached a consensus about biomechanical mechanism of the PRC, but there are still controversial conclusions on the biomechanics mechanism of the surrounding soft tissue to stability of distal radioulnar joint when the triangular fibrocartilage complex are damaged and the biomechanics mechanism of the scapholunate ligament. At present, there is no unified standard about the methods to repair or reconstruct the stability and function of the PRC. So, it is difficult for clinical practice. Some strides have been made in the basic biomechanical study on muscle and ligament and clinical biomechanical study on the methods to repair or reconstruct the stability and function of PRC, but it will be needed to further study the morphology of carpal articular surface and the adjacent articular surface, the pressure of distal carpals to proximal carpal and so on.

Proximate influences on female dispersal in white-tailed deer

USGS Publications Warehouse

Lutz, Clayton L.; Diefenbach, Duane R.; Rosenberry, Christopher S.

2016-01-01

Ultimate causes of animal dispersal have been hypothesized to benefit the dispersing individual because dispersal reduces competition for local resources, potential for inbreeding, and competition for breeding partners. However, proximate cues influence important features of dispersal behavior, including when dispersal occurs, how long it lasts, and direction, straightness, and distance of the dispersal path. Therefore, proximate cues that affect dispersal influence ecological processes (e.g., population dynamics, disease transmission, gene flow). We captured and radio-marked 277 juvenile female white-tailed deer (Odocoileus virginianus), of which 27 dispersed, to evaluate dispersal behavior and to determine proximate cues that may influence dispersal behavior. Female dispersal largely occurred at 1 year of age and coincided with the fawning season. Dispersal paths varied but generally were non-linear and prolonged. Physical landscape features (i.e., roadways, rivers, residential areas) influenced dispersal path direction and where dispersal terminated. Additionally, forays outside of the natal range that did not result in dispersal occurred among 52% of global positioning system (GPS)-collared deer (n = 25) during the dispersal period. Our results suggest intra-specific social interactions and physical landscape features influence dispersal behavior in female deer. Female dispersal behavior, particularly the lack of directionality, the semi-permeable nature of physical barriers, and the frequency of forays outside of the natal range, should be considered in regard to population management and controlling the spread of disease.

[MRI characteristic of proximal femur bone marrow edema syndrome].

PubMed

Wu, Xi-Yuan

2014-07-01

To study the MRI features of proximal femur bone marrow edema syndrome for further improve the understanding of the disease. MRI imaging of 10 patients with proximal femur bone marrow edema syndrome was retrospectively reviewed,including 6 males and 4 females with an average age of 41.5 years old ranging from 36 to 57. The courses of diseases ranged from 1 week to 3 months. Among them, 9 cases had clinical manifestations of sudden hip pain, 7 cases had limited ability of walking and hip movement;all patients had no obvious injury history, non of the female patients was pregnant. All patients were followed up from 3 to 12 months, the following-up were topped after MRI when the symptoms disappeared for 3 months. The MRI demonstrated diffuse bone marrow edema involving the femoral head, neck and the inter-trochanteric region, 13 hips of 10 patients with bone marrow edema included 6 cases in grade 1, 5 cases in grade 2,2 cases in grade 3; 9 hips with hip hydrarthrosis included 6 hips in grade I ,1 hip in grade II, 2 hips in grade III. After treatment for 3 to 12 months the hip symptoms of the patients disappeared and MRI images were normal. MRI is useful in defining the location and extent of proximal femur bone marrow edema syndrome.

Electromagnetic navigation reduces surgical time and radiation exposure for proximal interlocking in retrograde femoral nailing.

PubMed

Somerson, Jeremy S; Rowley, David; Kennedy, Chad; Buttacavoli, Frank; Agarwal, Animesh

2014-07-01

To compare the time required for proximal locking screw placement between a standard freehand technique and the navigated technique, and to quantify the reduction in ionizing radiation exposure. A fresh frozen cadaver model was used for 48 proximal interlocking screw procedures. Each procedure consisted of insertion of 2 anteroposterior locking screws. Standard fluoroscopic technique was used for 24 procedures, and an electromagnetic navigation system was used for the remaining 24 procedures. Procedure duration was recorded using an electronic timer and radiation doses were documented. Mean total insertion time for both proximal interlocking screws was 405 ± 165.7 seconds with the freehand technique and 311 ± 78.3 seconds in the navigation group (P = 0.002). All procedures resulted in successful locking screw placement. Mean ionizing radiation exposure time for proximal locking was 29.5 ± 12.8 seconds. Proximal locking screw insertion using the navigation technique evaluated in this work was significantly faster than the standard fluoroscopic method. The navigated technique is effective and has the potential to prevent ionizing radiation exposure.

Biomechanical analysis of two fixation methods for proximal chevron osteotomy of the first metatarsal.

PubMed

Schuh, Reinhard; Hofstaetter, Jochen Gerhard; Benca, Emir; Willegger, Madeleine; von Skrbensky, Gobert; Zandieh, Shahin; Wanivenhaus, Axel; Holinka, Johannes; Windhager, Reinhard

2014-05-01

The proximal chevron osteotomy provides high correctional power. However, relatively high rates of dorsiflexion malunion of up to 17 % are reported for this procedure. This leads to insufficient weight bearing of the first ray and therefore to metatarsalgia. Recent biomechanical and clinical studies pointed out the importance of rigid fixation of proximal metatarsal osteotomies. Therefore, the aim of the present study was to compare biomechanical properties of fixation of proximal chevron osteotomies with variable locking plate and cancellous screw respectively. Ten matched pairs of human fresh frozen cadaveric first metatarsals underwent proximal chevron osteotomy with either variable locking plate or cancellous screw fixation after obtaining bone mineral density. Biomechanical testing included repetitive plantar to dorsal loading from 0 to 31 N with the 858 Mini Bionix(®) (MTS(®) Systems Corporation, Eden Prairie, MN, USA). Dorsal angulation of the distal fragment was recorded. The variable locking plate construct reveals statistically superior results in terms of bending stiffness and dorsal angulation compared to the cancellous screw construct. There was a statistically significant correlation between bone mineral density and maximum tolerated load until construct failure occurred for the screw construct (r = 0.640, p = 0.406). The results of the present study indicate that variable locking plate fixation shows superior biomechanical results to cancellous screw fixation for proximal chevron osteotomy. Additionally, screw construct failure was related to levels of low bone mineral density. Based on the results of the present study we recommend variable locking plate fixation for proximal chevron osteotomy, especially in osteoporotic bone.

Inducible nitric oxide synthase and apoptosis in murine proximal tubule epithelial cells.

PubMed

Tiwari, Manish M; Messer, Kurt J; Mayeux, Philip R

2006-06-01

Since inducible nitric oxide synthase (iNOS) and proximal tubule injury are known to be critical determinants of lipopolysaccharide (LPS)-induced renal failure, the role of nitric oxide (NO) in proximal tubule cell apoptosis was examined. An 18-h treatment with a combination of LPS (5 microg/ml) and interferon-gamma (IFN-gamma, 100 units/ml) synergistically induced iNOS and produced a 20-fold increase in NO generation in the TKPTS murine proximal tubule cell line. NO generation by LPS + IFN-gamma was blocked by a specific iNOS blocker, L-N6-(1-iminoethyl)-lysine (L-NIL, 1 mM). To assess the role of iNOS-derived NO in proximal tubule cell apoptosis, annexin V- and propidium iodide-labeled cells were analyzed by flow cytometry. Neither the induction of iNOS nor its inhibition produced significant apoptotic cell death in TKPTS cells. Two exogenous NO donors were used to examine the role of NO more directly in proximal tubule apoptosis. Although both sodium nitroprusside (SNP), an iron-containing, nitrosonium cation donor, and S-nitroso-N-acetylpenicillamine (SNAP), a noniron-containing, NO generator, produced a concentration-dependent increase in NO generation, only SNP increased apoptotic cell death in TKPTS cells (5.9 +/- 0.7% in control cells vs. 21.6 +/- 3.8% in SNP [500 microM]-treated cells; n = 4-9; p < 0.01). SNP-mediated tubule cell apoptosis was not dependent on the activation of caspases or p53 but was possibly related to the generation of reactive oxygen species by SNP. Thus, in TKPTS cells induction of iNOS and generation of NO by LPS does not lead to tubular epithelial cell death.

Design of intelligent proximity detection zones to prevent striking and pinning fatalities around continuous mining machines.

PubMed

Bissert, P T; Carr, J L; DuCarme, J P; Smith, A K

2016-01-01

The continuous mining machine is a key piece of equipment used in underground coal mining operations. Over the past several decades these machines have been involved in a number of mine worker fatalities. Proximity detection systems have been developed to avert hazards associated with operating continuous mining machines. Incorporating intelligent design into proximity detection systems allows workers greater freedom to position themselves to see visual cues or avoid other hazards such as haulage equipment or unsupported roof or ribs. However, intelligent systems must be as safe as conventional proximity detection systems. An evaluation of the 39 fatal accidents for which the Mine Safety and Health Administration has published fatality investigation reports was conducted to determine whether the accident may have been prevented by conventional or intelligent proximity. Multiple zone configurations for the intelligent systems were studied to determine how system performance might be affected by the zone configuration. Researchers found that 32 of the 39 fatalities, or 82 percent, may have been prevented by both conventional and intelligent proximity systems. These results indicate that, by properly configuring the zones of an intelligent proximity detection system, equivalent protection to a conventional system is possible.

Detection of proximal caries using digital radiographic systems with different resolutions.

PubMed

Nikneshan, Sima; Abbas, Fatemeh Mashhadi; Sabbagh, Sedigheh

2015-01-01

Dental radiography is an important tool for detection of caries and digital radiography is the latest advancement in this regard. Spatial resolution is a characteristic of digital receptors used for describing the quality of images. This study was aimed to compare the diagnostic accuracy of two digital radiographic systems with three different resolutions for detection of noncavitated proximal caries. Diagnostic accuracy. Seventy premolar teeth were mounted in 14 gypsum blocks. Digora; Optime and RVG Access were used for obtaining digital radiographs. Six observers evaluated the proximal surfaces in radiographs for each resolution in order to determine the depth of caries based on a 4-point scale. The teeth were then histologically sectioned, and the results of histologic analysis were considered as the gold standard. Data were entered using SPSS version 18 software and the Kruskal-Wallis test was used for data analysis. P <0.05 was considered as statistically significant. No significant difference was found between different resolutions for detection of proximal caries (P > 0.05). RVG access system had the highest specificity (87.7%) and Digora; Optime at high resolution had the lowest specificity (84.2%). Furthermore, Digora; Optime had higher sensitivity for detection of caries exceeding outer half of enamel. Judgment of oral radiologists for detection of the depth of caries had higher reliability than that of restorative dentistry specialists. The three resolutions of Digora; Optime and RVG access had similar accuracy in detection of noncavitated proximal caries.

Proximal Association of Land Management Preferences: Evidence from Family Forest Owners

PubMed Central

Aguilar, Francisco X.; Cai, Zhen; Butler, Brett

2017-01-01

Individual behavior is influenced by factors intrinsic to the decision-maker but also associated with other individuals and their ownerships with such relationship intensified by geographic proximity. The land management literature is scarce in the spatially integrated analysis of biophysical and socio-economic data. Localized land management decisions are likely driven by spatially-explicit but often unobserved resource conditions, influenced by an individual’s own characteristics, proximal lands and fellow owners. This study examined stated choices over the management of family-owned forests as an example of a resource that captures strong pecuniary and non-pecuniary values with identifiable decision makers. An autoregressive model controlled for spatially autocorrelated willingness-to-harvest (WTH) responses using a sample of residential and absentee family forest owners from the U.S. State of Missouri. WTH responses were largely explained by affective, cognitive and experience variables including timber production objectives and past harvest experience. Demographic variables, including income and age, were associated with WTH and helped define socially-proximal groups. The group of closest identity was comprised of resident males over 55 years of age with annual income of at least $50,000. Spatially-explicit models showed that indirect impacts, capturing spillover associations, on average accounted for 14% of total marginal impacts among statistically significant explanatory variables. We argue that not all proximal family forest owners are equal and owners-in-absentia have discernible differences in WTH preferences with important implications for public policy and future research. PMID:28060960

SGLT2 Inhibitors: Glucotoxicity and Tumorigenesis Downstream the Renal Proximal Tubule?

PubMed

Bertinat, Romina; Nualart, Francisco; Yáñez, Alejandro J

2016-08-01

At present, diabetes mellitus is the main cause of end-stage renal disease. Effective glycaemic management is the most powerful tool to delay the establishment of diabetic complications, such as diabetic kidney disease. Together with reducing blood glucose levels, new anti-diabetic agents are expected not only to control the progression but also to restore known defects of the diabetic kidney. Sodium-glucose co-transporter 2 (SGLT2) inhibitors are promising anti-diabetic agents that reduce hyperglycaemia by impairing glucose reabsorption in proximal tubule of the kidney and increasing glucosuria. SGLT2 inhibitors have shown to reduce glucotoxicity in isolated proximal tubule cells and also to attenuate expression of markers of overall kidney damage in experimental animal models of diabetes, but the actual renoprotective effect for downstream nephron segments is still unknown and deserves further attention. Here, we briefly discuss possible undesired effects of enhanced glucosuria and albuminuria in nephron segments beyond the proximal tubule after SGLT2 inhibitor treatment, offering new lines of research to further understand the renoprotective action of these anti-diabetic agents. Strategies blocking glucose reabsorption by renal proximal tubule epithelial cells (RPTEC) may be protective for RPTEC, but downstream nephron segments will still be exposed to high glucose and albumin levels through the luminal face. The actual effect of constant enhanced glucosuria over distal nephron segments remains to be established. J. Cell. Physiol. 231: 1635-1637, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Proximity of fast food restaurants to schools: do neighborhood income and type of school matter?

PubMed

Simon, Paul A; Kwan, David; Angelescu, Aida; Shih, Margaret; Fielding, Jonathan E

2008-09-01

To investigate the proximity of fast food restaurants to public schools and examine proximity by neighborhood income and school level (elementary, middle, or high school). Geocoded school and restaurant databases from 2005 and 2003, respectively, were used to determine the percentage of schools with one or more fast food restaurants within 400 m and 800 m of all public schools in Los Angeles County, California. Single-factor analysis of variance (ANOVA) models were run to examine fast food restaurant proximity to schools by median household income of the surrounding census tract and by school level. Two-factor ANOVA models were run to assess the additional influence of neighborhood level of commercialization. Overall, 23.3% and 64.8% of schools had one or more fast food restaurants located within 400 m and 800 m, respectively. Fast food restaurant proximity was greater for high schools than for middle and elementary schools, and was inversely related to neighborhood income for schools in the highest commercial areas. No association with income was observed in less commercial areas. Fast food restaurants are located in close proximity to many schools in this large metropolitan area, especially high schools and schools located in low income highly commercial neighborhoods. Further research is needed to assess the relationship between fast food proximity and student dietary practices and obesity risk.

Sciatic Nerve Injury After Proximal Hamstring Avulsion and Repair

PubMed Central

Wilson, Thomas J.; Spinner, Robert J.; Mohan, Rohith; Gibbs, Christopher M.; Krych, Aaron J.

2017-01-01

Background: Muscle bellies of the hamstring muscles are intimately associated with the sciatic nerve, putting the sciatic nerve at risk of injury associated with proximal hamstring avulsion. There are few data informing the magnitude of this risk, identifying risk factors for neurologic injury, or determining neurologic outcomes in patients with distal sciatic symptoms after surgery. Purpose: To characterize the frequency and nature of sciatic nerve injury and distal sciatic nerve–related symptoms after proximal hamstring avulsion and to characterize the influence of surgery on these symptoms. Study Design: Cohort study; Level of evidence, 3. Methods: This was a retrospective review of patients with proximal partial or complete hamstring avulsion. The outcome of interest was neurologic symptoms referable to the sciatic nerve distribution below the knee. Neurologic symptoms in operative patients were compared pre- and postoperatively. Results: The cohort consisted of 162 patients: 67 (41.4%) operative and 95 (58.6%) nonoperative. Sciatic nerve–related symptoms were present in 22 operative and 23 nonoperative patients, for a total of 45 (27.8%) patients (8 [4.9%] motor deficits, 11 [6.8%] sensory deficits, and 36 [22.2%] with neuropathic pain). Among the operative cohort, 3 of 3 (100.0%) patients showed improvement in their motor deficit postoperatively, 3 of 4 (75.0%) patients’ sensory symptoms improved, and 17 of 19 (89.5%) patients had improvement in pain. A new or worsening deficit occurred in 5 (7.5%) patients postoperatively (2 [3.1%] motor deficits, 1 [1.5%] sensory deficit, and 3 [4.5%] with new pain). Predictors of operative intervention included lower age (odds ratio [OR], 0.952; 95% CI, 0.921-0.982; P = .001) and complete avulsion (OR, 10.292; 95% CI, 2.526-72.232; P < .001). Presence of neurologic deficit was not predictive. Conclusion: Sciatic nerve–related symptoms after proximal hamstring avulsion are underrecognized. Currently, neurologic

Sciatic Nerve Injury After Proximal Hamstring Avulsion and Repair.

PubMed

Wilson, Thomas J; Spinner, Robert J; Mohan, Rohith; Gibbs, Christopher M; Krych, Aaron J

2017-07-01

Muscle bellies of the hamstring muscles are intimately associated with the sciatic nerve, putting the sciatic nerve at risk of injury associated with proximal hamstring avulsion. There are few data informing the magnitude of this risk, identifying risk factors for neurologic injury, or determining neurologic outcomes in patients with distal sciatic symptoms after surgery. To characterize the frequency and nature of sciatic nerve injury and distal sciatic nerve-related symptoms after proximal hamstring avulsion and to characterize the influence of surgery on these symptoms. Cohort study; Level of evidence, 3. This was a retrospective review of patients with proximal partial or complete hamstring avulsion. The outcome of interest was neurologic symptoms referable to the sciatic nerve distribution below the knee. Neurologic symptoms in operative patients were compared pre- and postoperatively. The cohort consisted of 162 patients: 67 (41.4%) operative and 95 (58.6%) nonoperative. Sciatic nerve-related symptoms were present in 22 operative and 23 nonoperative patients, for a total of 45 (27.8%) patients (8 [4.9%] motor deficits, 11 [6.8%] sensory deficits, and 36 [22.2%] with neuropathic pain). Among the operative cohort, 3 of 3 (100.0%) patients showed improvement in their motor deficit postoperatively, 3 of 4 (75.0%) patients' sensory symptoms improved, and 17 of 19 (89.5%) patients had improvement in pain. A new or worsening deficit occurred in 5 (7.5%) patients postoperatively (2 [3.1%] motor deficits, 1 [1.5%] sensory deficit, and 3 [4.5%] with new pain). Predictors of operative intervention included lower age (odds ratio [OR], 0.952; 95% CI, 0.921-0.982; P = .001) and complete avulsion (OR, 10.292; 95% CI, 2.526-72.232; P < .001). Presence of neurologic deficit was not predictive. Sciatic nerve-related symptoms after proximal hamstring avulsion are underrecognized. Currently, neurologic symptoms are not considered when determining whether to pursue operative

True Ulnar Artery Aneurysm in the Proximal Forearm: Case Report and Literature Review.

PubMed

McHugh, Seamus Mark; Moloney, Michael Anthony; Greco, Elisa; Wheatcroft, Mark

2017-10-01

Ulnar artery aneurysms are rare with less than 150 previously reported. Previously ulnar aneurysms have been most commonly noted as occurring in the distal ulnar artery close to the palmar arch. We present the case of a 47-year-old male with a background history of human immunodeficiency virus (HIV) who attended our outpatient clinic with symptoms of distal embolization from a proximal ulnar artery aneurysm. Preoperatively, the aneurysm was thought to arise from the distal brachial artery, and only intraoperatively was the diagnosis of ulnar aneurysm made. The aneurysm was excised, and a reverse vein bypass graft anastomosed end to side on the brachial artery, and end to end on the distal ulnar. True ulnar artery aneurysms also involving the more proximal ulnar artery have been previously reported associated with vasculitic disorders. HIV has been previously associated with aneurysm formation in a number of anatomical locations. This case is noteworthy as it reports on the presentation and successful operative management of a true ulnar artery aneurysm arising in the proximal forearm in the setting of HIV, which has not been previously reported in medical literature. We present successful operative management of a true ulnar aneurysm in the proximal forearm using a reverse venous interposition bypass. Diagnosis of a proximal ulnar artery aneurysm may represent a diagnostic challenge given its rarity as it may mimic brachial artery aneurysm. Copyright © 2017 Elsevier Inc. All rights reserved.

Role of estrogen and progesterone in the modulation of CNG-A1 and Na/K+-ATPase expression in the renal cortex.

PubMed

Gracelli, Jones B; Souza-Menezes, Jackson; Barbosa, Carolina M L; Ornellas, Felipe S; Takiya, Christina M; Alves, Leandro M; Wengert, Mira; Feltran, Georgia da Silva; Caruso-Neves, Celso; Moyses, Margareth R; Prota, Luiz F M; Morales, Marcelo M

2012-01-01

The steroid hormones, estrogen and progesterone, are involved mainly in the control of female reproductive functions. Among other effects, estrogen and progesterone can modulate Na(+) reabsorption along the nephron altering the body's hydroelectrolyte balance. In this work, we analyzed the expression of cyclic nucleotide-gated channel A1 (CNG-A1) and α1 Na(+)/K(+)-ATPase subunit in the renal cortex and medulla of female ovariectomized rats and female ovariectomized rats subjected to 10 days of 17β-estradiol benzoate (2.0 µg/kg body weight) and progesterone (1.7 mg/kg body weight) replacement. Na(+)/K(+) ATPase activity was also measured. Immunofluorescence localization of CNG-A1 in the cortex and medulla was performed in control animals. We observed that CNG-A1 is localized at the basolateral membrane of proximal and distal tubules. Female ovariectomized rats showed low expression of CNG-A1 and low expression and activity of Na(+)/K(+) ATPase in the renal cortex. When female ovariectomized rats were subjected to 17β-estradiol benzoate replacement, normalization of CNG-A1 expression and Na(+)/K(+) ATPase expression and activity was observed. The replacement of progesterone was not able to recover CNG-A1 expression and Na(+)/K(+) ATPase expression at the control level. Only the activity of Na(+)/K(+) ATPase was able to be recovered at control levels in animals subjected to progesterone replacement. No changes in expression and activity were observed in the renal medulla. The expression of CNG-A1 is higher in cortex compared to medulla. In this work, we observed that estrogen and progesterone act in renal tissues modulating CNG-A1 and Na(+)/K(+) ATPase and these effects could be important in Na(+) and water balance. Copyright © 2012 S. Karger AG, Basel.

[Imaging evaluation on adaptability of proximal humeral anatomy after shoulder replacement with individualized shoulder prosthesis].

PubMed

Shi, Youxing; Tang, Kanglai; Yuan, Chengsong; Tao, Xu; Wang, Huaqing; Chen, Bo; Guo, Yupeng

2015-03-24

Modern shoulder prosthesis has evolved through four generations. And the fourth generation technology has a core three-dimensional design of restoring 3D reconstruction of proximal humeral anatomy. Thus a new shoulder prosthesis is developed on the basis of the technology of 3D prosthesis. Assessment of whether shoulder prosthesis can restore individualized reconstruction of proximal humeral anatomy is based on the adaptability of proximal humeral anatomy. To evaluate the adaptability of proximal humeral anatomy through measuring the parameters of proximal humeral anatomy after shoulder replacement with individualized shoulder prosthesis and compare with normal data. The parameters of proximal humeral anatomy were analyzed and evaluated for a total of 12 cases undergoing shoulder replacement with individualized shoulder prosthesis. The relevant anatomical parameters included neck-shaft angle (NSA), retroversion angle (RA), humeral head height (HH) and humeral head diameter (HD). And the anatomical parameters were compared with the data from normal side. All underwent shoulder replacement with individualized shoulder prosthesis. The postoperative parameters of proximal humeral anatomy were compared with those of normal side. And the difference of NSA was < 3°, RA < 3°, HH < 3 mm and HD < 2 mm. And paired-sample t test was used to study the parameters of proximal humeral anatomy between postoperative and normal side. The normal and postoperative NSA was (140.2 ± 6.8)° and (139.5 ± 6.6)° respectively, RA (34.4 ± 3.3)° and (33.8-3.1)°, HH (15.3 ± 2.1) mm and (14.6+0.9) mm, HW (42.2 ± 2.82) mm and (41.8 ± 2.33) mm respectively. No significant difference existed between two groups (P > 0.05). Individualized shoulder prosthesis has excellent adaptability to shoulder. All core parameters are freely adjustable and specification models may be optimized. With matching tools, individualized shoulder prosthesis improves the accuracy and reliability in shoulder

[Microsurgery for severe flexion contracture of proximal interphalangeal joint].

PubMed

Fei, Xiaoxuan; Feng, Shiming; Gao, Shunhong

2012-07-01

To investigate the clinical results of cross-finger flap combined with laterodigital pedicled skin flap for repair of severe flexion contracture of the proximal interphalangeal joint. Between October 2008 and February 2011, 11 patients (11 fingers) with severe flexion contracture of the proximal interphalangeal joint were treated with cross-finger flap combined with laterodigital pedicled skin flap. There were 7 males and 4 females, aged 20-63 years (mean, 32.6 years). The causes of injury were crush or electric-saw injury in 7 cases, burn or explosive injury in 3 cases, and electrical injury in 1 case. The locations were the index finger in 4 cases, the middle finger in 2 cases, the ring finger in 2 cases, and the little finger in 3 cases. The mean disease duration was 12.4 months (range, 6-24 months). All cases were rated as type III according to Stern classification standard. The volar tissue defect ranged from 3.0 cm x 1.5 cm to 5.0 cm x 2.5 cm, with exposed tendons, nerves, vessels, or bone after scar relaxation. The defects were repaired with cross-finger flaps (2.2 cm x 1.8 cm to 3.8 cm x 2.5 cm) combined with laterodigital pedicled skin flaps (1.5 cm x 1.2 cm to 2.5 cm x 2.0 cm). Double laterodigital pedicled skin flaps were used in 3 cases. The flap donor site was sutured directly or repaired with the skin graft. All flaps survived completely and wound healed by first intention. The donor skin graft survived. All the patients were followed up 6-18 months (mean, 11.3 months). The finger appearance was satisfactory. The flaps had soft texture and good color in all cases. No obvious pigmentation or contraction was observed. The contracted fingers could extend completely with good active flexion and extension motion. At last follow-up, the extension of the proximal interphalangeal joint was 10-150. Based on proximal interphalangeal joint motion standard of Chinese Medical Association for hand surgery, the results were excellent in 6 cases, good in 4 cases, and

Meissner effect in normal-superconducting proximity-contact double layers

NASA Astrophysics Data System (ADS)

Higashitani, Seiji; Nagai, Katsuhiko

1995-02-01

The Meissner effect in normal-superconducting proximity-contact double layers is discussed in the clean limit. The diamagnetic current is calculated using the quasi-classical Green's function. We obtain the quasi-classical Green's function linear in the vector potential in the proximity-contact double layers with a finite reflection coefficient at the interface. It is found that the diamagnetic current in the clean normal layer is constant in space, therefore, the magnetic field linearly decreases in the clean normal layer. We give an explicit expression for the screening length in the clean normal layer and study its temperature dependence. We show that the temperature dependence in the clean normal layer is considerably different from that in the dirty normal layer and agrees with a recent experiment in Au-Nb system.

Mutual proximity graphs for improved reachability in music recommendation.

PubMed

Flexer, Arthur; Stevens, Jeff

2018-01-01

This paper is concerned with the impact of hubness, a general problem of machine learning in high-dimensional spaces, on a real-world music recommendation system based on visualisation of a k-nearest neighbour (knn) graph. Due to a problem of measuring distances in high dimensions, hub objects are recommended over and over again while anti-hubs are nonexistent in recommendation lists, resulting in poor reachability of the music catalogue. We present mutual proximity graphs, which are an alternative to knn and mutual knn graphs, and are able to avoid hub vertices having abnormally high connectivity. We show that mutual proximity graphs yield much better graph connectivity resulting in improved reachability compared to knn graphs, mutual knn graphs and mutual knn graphs enhanced with minimum spanning trees, while simultaneously reducing the negative effects of hubness.

Na+/Ca2+ exchange and Na+/K+-ATPase in the heart

PubMed Central

Shattock, Michael J; Ottolia, Michela; Bers, Donald M; Blaustein, Mordecai P; Boguslavskyi, Andrii; Bossuyt, Julie; Bridge, John H B; Chen-Izu, Ye; Clancy, Colleen E; Edwards, Andrew; Goldhaber, Joshua; Kaplan, Jack; Lingrel, Jerry B; Pavlovic, Davor; Philipson, Kenneth; Sipido, Karin R; Xie, Zi-Jian

2015-01-01

This paper is the third in a series of reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na+ channel and Na+ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on cardiac Na+/Ca2+ exchange (NCX) and Na+/K+-ATPase (NKA). While the relevance of Ca2+ homeostasis in cardiac function has been extensively investigated, the role of Na+ regulation in shaping heart function is often overlooked. Small changes in the cytoplasmic Na+ content have multiple effects on the heart by influencing intracellular Ca2+ and pH levels thereby modulating heart contractility. Therefore it is essential for heart cells to maintain Na+ homeostasis. Among the proteins that accomplish this task are the Na+/Ca2+ exchanger (NCX) and the Na+/K+ pump (NKA). By transporting three Na+ ions into the cytoplasm in exchange for one Ca2+ moved out, NCX is one of the main Na+ influx mechanisms in cardiomyocytes. Acting in the opposite direction, NKA moves Na+ ions from the cytoplasm to the extracellular space against their gradient by utilizing the energy released from ATP hydrolysis. A fine balance between these two processes controls the net amount of intracellular Na+ and aberrations in either of these two systems can have a large impact on cardiac contractility. Due to the relevant role of these two proteins in Na+ homeostasis, the emphasis of this review is on recent developments regarding the cardiac Na+/Ca2+ exchanger (NCX1) and Na+/K+ pump and the controversies that still persist in the field. PMID:25772291

The treatment of an osteochondral shearing fracture-dislocation of the head of the proximal phalanx: a case report.

PubMed

Harness, Neil; Jupiter, Jesse B

2004-09-01

We report the morphology and treatment of a proximal interphalangeal joint dislocation resulting in an injury to the articular surface of the proximal phalanx and avulsion of the radial collateral ligament from its proximal origin. A large osteochondral fragment was sheared from the radial articular surface of the proximal phalanx and remained displaced volarly after reduction of the joint. Plain radiographs and 2- and 3-dimensional computed tomography images were used to evaluate this unusual injury before surgery. Open reduction and internal fixation using a small K-wire and figure-of-eight wire technique restored the articular surface of the head of the proximal phalanx and gave a satisfactory functional result.

Sonographic evaluation of proximal gastric accommodation in patients with functional dyspepsia

PubMed Central

Fan, Xiu-Ping; Wang, Lin; Zhu, Qiang; Ma, Teng; Xia, Chun-Xia; Zhou, Ya-Jing

2013-01-01

AIM: To assess the value of ultrasonography (US) in evaluation of proximal gastric accommodation disorder in patients with functional dyspepsia (FD). METHODS: Between April 2011 and March 2012, 45 patients with FD and 27 healthy volunteers were enrolled in this study. Two-dimensional ultrasound (2DUS) and 3-dimensional ultrasound (3DUS) were performed sequentially to measure proximal gastric area (PGA), maximal proximal gastric diameter (MPGD), and proximal gastric volume (PGV). These values were measured separately in the two groups every other 5 min for a duration of 25 min after the beginning of ingestion of a test meal. Air pocket grading was done separately for images of 2DUS and blocks of 3DUS obtained at five scanning time points. RESULTS: Both PGA and PGV of patients were significantly smaller than healthy controls (P = 0.000 and 0.002, respectively). Comparing the two parameters between the groups at each time point, the differences were also statistically significant (P = 0.000-0.013), except at 10 min for the PGV (P = 0.077). However, no overall difference was found between the groups in the MPGD measurements (P = 0.114), though it was statistically significant at a 20-minute examination point (P = 0.026). A total of 360 sets or blocks of images were obtained for both 2DUS and 3DUS. For the images analyzed by 2DUS, none were excluded because of gastric gas, and 50 (13.9%) and 310 (86.1%) sets were determined as air pockets grades 1 and 2, respectively. For the images analyzed by 3DUS, 23 (6.4%) blocks were excluded from the measurement due to presence of a large fundus air pocket (grade 3); fifty (13.9%) and 287 (79.7%) blocks were also graded as 1 and 2, respectively. CONCLUSION: Measurement of both PGA and PGV by 2DUS and 3DUS could be useful for assessment of the proximal gastric accommodation. PMID:23922476

Instrumentation Strategies to Reduce the Risks of Proximal Junctional Kyphosis in Adult Scoliosis: A Detailed Biomechanical Analysis.

PubMed

Aubin, Carl-Eric; Cammarata, Marco; Wang, Xiaoyu; Mac-Thiong, Jean-Marc

2015-05-01

Biomechanical analysis of proximal junctional kyphosis (PJK) through numerical simulations. Assessment of the effect of sagittal alignment, the upper instrumented vertebral level (UIV), and 4 other surgical variables on biomechanical indices related to the PJK risks. Despite retrospective clinical studies, biomechanical analysis of individual parameters associated with PJK is lacking to support instrumentation strategies to reduce the PJK risks. Instrumentations of 6 adult scoliosis cases with different operative strategies were simulated (1,152 simulations). Proximal junctional (PJ) angle and flexion loads were evaluated against the sagittal alignment and the proximal instrumentation level. Instrumenting 1 more proximal vertebra allowed the PJ angle, proximal moment, and force to be reduced by 18%, 25%, and 16%, respectively. Shifting sagittal alignment by 20 mm posteriorly increased the PJ angle and proximal moment by 16% and 22%, and increased the equivalent posterior extensor force by 37%. Bilateral complete facetectomy, posterior ligaments resection, and the combination of the 2 resulted in an increase of the PJ angle (by 10%, 28%, and 53%, respectively), flexion forces (by 4%, 12%, and 22%, respectively), and proximal moments (by 16%, 44%, and 83%, respectively). Transverse process hooks at UIV compared with pedicle screws allowed 26% lower PJ angle and flexion loads. The use of proximal transition rods with proximal diameter reduced from 5.5 to 4 mm slightly reduced PJ angle, flexion force, and moment (less than 8%). The increase in sagittal rod curvature from 10° to 40° increased the PJ angle (from 6% to 19%), flexion force (from 3% to 10%), and moment (from 9% to 27%). Simulated posteriorly shifted sagittal alignment was associated with higher PJK risks, whereas extending instrumentation proximally allowed a lower mechanical risk of PJK. Preserving PJ intervertebral elements and using a more flexible anchorage at UIV help reduce the biomechanical risks

Dating young tephras - a distal solution to proximal controversy

NASA Astrophysics Data System (ADS)

Chen, Xuanyu; Blockley, Simon; Xu, Yigang; Menzies, Martin

2017-04-01

In-situ dating of young volcanic rocks (<50ka) is fraught with difficulties, a classic example being Changbaishan Volcano NE China. During the caldera-forming 'Millennium' eruption (ca. 940-950 CE) tephra was deposited around the world and as primary fall deposits on the caldera rims. The proximal deposits have been studied using multiple dating methods (e.g. 14C, 40Ar/39Ar, U-series and TL) but controversy and contradiction surrounds the age of these tephra deposits and, as a consequence, the proximal stratigraphy of the 'Millennium' eruption. Accurate characterization of the 'Millennium' tephra is vital if the tephras are to be used to reliably link disparate palaeoclimate archives on a hemispheric-wide scale. Our approach has been to use glass geochemistry to correlate the proximal units with a distal lake sequence from Lake Kushu Japan ca. 1100 km from Changbaishan. Investigation of a 19 m lake core revealed a crypto-tephra deposit with an approximate 'Millennium' age (i.e., 913-1395 cal. CE, 95.4% confidence), confirmed by the 14C-based Bayesian age model of the sedimentary record. Geochemical analysis of tephra shards for both proximal and distal deposits, confirmed identical major, minor and trace element chemistry. This allowed us to correlate the distal crypto-tephra with proximal pyroclastic fall units and to revise the 'Millennium' stratigraphy. Contrary to published data we propose that the 'Millennium' eruption is evident as a composite proximal sequence and that there is no evidence of any post-caldera deposits at the investigated profile (Chen et al., 2016). This is a significant step in our understanding of the nature and timing of Changbaishan eruptions and allows us to resolve an uncertain stratigraphy and eruption history. The correlation of the Lake Kushu crypto-tephra deposit to the distal Millennium (i.e., B-Tm) tephra reported from the Greenland ice-core (Sun et al., 2014) allows the use of high resolution ice-core tephra ages to validate and

Spacecraft Guidance Strategies for Proximity Maneuvering and Close Approach with a Tumbling Object

DTIC Science & Technology

2010-03-01

R., and Junkins, J. L. (1984), ‘Optimal Open-Loop and Stable Feedback Control of Rigid Spacecraft Attitude Maneuvers ,’ The Journal of the... SPACECRAFT GUIDANCE STRATEGIES FOR PROXIMITY MANEUVERING AND CLOSE APPROACH WITH A TUMBLING OBJECT by George A. Boyarko March 2010...Dissertation 4. TITLE AND SUBTITLE: Spacecraft Guidance Strategies for Proximity Maneuvering and Close Approach with a Tumbling Object 6. AUTHOR

Ligament augmentation for prevention of proximal junctional kyphosis and proximal junctional failure in adult spinal deformity.

PubMed

Safaee, Michael M; Deviren, Vedat; Dalle Ore, Cecilia; Scheer, Justin K; Lau, Darryl; Osorio, Joseph A; Nicholls, Fred; Ames, Christopher P

2018-05-01

OBJECTIVE Proximal junctional kyphosis (PJK) is a well-recognized, yet incompletely defined, complication of adult spinal deformity surgery. There is no standardized definition for PJK, but most studies describe PJK as an increase in the proximal junctional angle (PJA) of greater than 10°-20°. Ligament augmentation is a novel strategy for PJK reduction that provides strength to the upper instrumented vertebra (UIV) and adjacent segments while also reducing junctional stress at those levels. METHODS In this study, ligament augmentation was used in a consecutive series of adult spinal deformity patients at a single institution. Patient demographics, including age; sex; indication for surgery; revision surgery; surgical approach; and use of 3-column osteotomies, vertebroplasty, or hook fixation at the UIV, were collected. The PJA was measured preoperatively and at last follow-up using 36-inch radiographs. Data on change in PJA and need for revision surgery were collected. Univariate and multivariate analyses were performed to identify factors associated with change in PJA and proximal junctional failure (PJF), defined as PJK requiring surgical correction. RESULTS A total of 200 consecutive patients were included: 100 patients before implementation of ligament augmentation and 100 patients after implementation of this technique. The mean age of the ligament augmentation cohort was 66 years, and 67% of patients were women. Over half of these cases (51%) were revision surgeries, with 38% involving a combined anterior or lateral and posterior approach. The mean change in PJA was 6° in the ligament augmentation group compared with 14° in the control group (p < 0.001). Eighty-four patients had a change in PJA of less than 10°. In a multivariate linear regression model, age (p = 0.016), use of hook fixation at the UIV (p = 0.045), and use of ligament augmentation (p < 0.001) were associated with a change in PJA. In a separate model, only ligament augmentation (OR 0

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

Obesity and supermarket access: proximity or price?

PubMed

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

2012-08-01

We examined whether physical proximity to supermarkets or supermarket price was more strongly associated with obesity risk. 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. 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) Improving physical access to supermarkets may be one strategy to deal with the obesity epidemic; improving economic access to healthy foods is another.

Bypass of the maxillary artery to proximal middle cerebral artery.

PubMed

Ma, Lin; Ren, He-cheng; Huang, Ying

2015-03-01

The objective of this work was to explore the feasibility of bypass between the maxillary artery (MA) and proximity of middle cerebral artery (MCA). Ten fixed and perfused adult cadaver heads were dissected bilaterally, 20 sides in total. The superficial temporal artery and its 2 branches were dissected, and outer diameters were measured. The MA and its branch were exposed as well as deep temporal artery; outer diameter of MA was measured. The lengths between the external carotid artery, internal carotid artery, maxillary artery, and proximal middle cerebral artery were measured. Ten healthy adults as targets (20 sides), inner diameter and blood flow dynamic parameters of the common carotid artery, external carotid artery, internal carotid artery, maxillary artery, superficial temporal artery, and its 2 branches were done with ultrasound examination. The mean outer diameter of MA (2.60 ± 0.20 mm) was larger than that of the temporal artery trunk (1.70 ± 0.30 mm). The mean lengths of graft vessels between the internal carotid artery, external carotid artery, and the bifurcation section of MCA (171.00 ± 2.70 and 162.40 ± 2.60 mm) were longer than the mean lengths of graft vessels between MA and MCA bifurcation section (61.70 ± 1.50 mm). In adults, the mean blood flow of the second part of MA (62.70 ± 13.30 mL/min) was more than that of the 2 branches of the superficial temporal artery (15.90 ± 3.70 mL/min and 17.70 ± 4.10 ml/min). Bypass between the maxillary artery and proximity of middle cerebral artery is feasible. It is a kind of effective high flow bypass with which the graft vessel is shorter and straighter than the bypass between internal carotid artery or external carotid artery and proximity of middle cerebral artery.

Proximal Humerus Fractures: Evaluation and Management in the Elderly Patient

PubMed Central

Grawe, Brian

2018-01-01

Introduction: Proximal humerus fractures are common in the elderly. The evaluation and management of these injuries is often controversial. The purpose of this study is to review recent evidence and provide updated recommendations for treating proximal humerus fractures in the elderly. Methods: A literature review of peer-reviewed publications related to the evaluation and management of proximal humerus fractures in the elderly was performed. There was a focus on randomized controlled trials and systematic reviews published within the last 5 years. Results: The incidence of proximal humerus fractures is increasing. It is a common osteoporotic fracture. Bone density is a predictor of reduction quality and can be readily assessed with anteroposterior views of the shoulder. Social independence is a predictor of outcome, whereas age is not. Many fractures are minimally displaced and respond acceptably to nonoperative management. Displaced and severe fractures are most frequently treated operatively with intramedullary nails, locking plates, percutaneous techniques, or arthroplasty. Discussion: Evidence from randomized controlled trials and systematic reviews is insufficient to recommend a treatment; however, most techniques have acceptable or good outcomes. Evaluation should include an assessment of the patient’s bone quality, social independence, and surgical risk factors. With internal fixation, special attention should be paid to medial comminution, varus angulation, and restoration of the calcar. With arthroplasty, attention should be paid to anatomic restoration of the tuberosities and proper placement of the prosthesis. Conclusion: A majority of minimally displaced fractures can be treated conservatively with early physical therapy. Treatment for displaced fractures should consider the patient’s level of independence, bone quality, and surgical risk factors. Fixation with percutaneous techniques, intramedullary nails, locking plates, and arthroplasty are all

Cyclophilin B expression in renal proximal tubules of hypertensive rats.

PubMed

Kainer, D B; Doris, P A

2000-04-01

Rat cyclophilin-like protein (Cy-LP) is a candidate hypertension gene initially identified by differential hybridization and implicated in renal mechanisms of salt retention and high blood pressure. We report the molecular characterization of rat cyclophilin B (CypB) and demonstrate, through sequence analysis and an allele-specific polymerase chain reaction primer assay, that CypB but not Cy-LP is expressed in rat kidney. CypB is an endoplasmic reticulum-localized prolyl-isomerase that interacts with elongation initiation factor 2-beta, an important regulator of protein translation and a central component of the endoplasmic reticulum stress response to hypoxia or ATP depletion. Active renal transport of sodium is increased in the spontaneously hypertensive rat (SHR), and there is evidence that this coincides with hypoxia and ATP depletion in the renal cortex. In the present studies we have examined expression of CypB in rat proximal tubules, which contributes to the increased renal sodium reabsorption in this model of hypertension. We report that CypB transcript abundance is significantly elevated in proximal convoluted tubules from SHR compared with the control Wistar-Kyoto strain. This upregulation occurs in weanling animals and precedes the development of hypertension, indicating that it is not a simple response to hypertension in SHR. Further, CypB expression is also higher in a proximal tubule cell line derived from SHR compared with a similar line derived from Wistar-Kyoto rats, indicating that this difference is genetically determined. No sequence differences were observed in the CypB cDNA from these 2 strains. These observations suggest that a genetically determined alteration in proximal tubules from SHR occurs that leads to increased expression of CypB. In view of evidence linking CypB to the regulation of elongation initiation factor-2, the upregulation of CypB may result from metabolic stress.

Costs and Effectiveness of Treatment Alternatives for Proximal Caries Lesions

PubMed Central

Schwendicke, Falk; Meyer-Lueckel, Hendrik; Stolpe, Michael; Dörfer, Christof Edmund; Paris, Sebastian

2014-01-01

Objectives Invasive therapy of proximal caries lesions initiates a cascade of re-treatment cycles with increasing loss of dental hard tissue. Non- and micro-invasive treatment aim at delaying this cascade and may thus reduce both the health and economic burden of such lesions. This study compared the costs and effectiveness of alternative treatments of proximal caries lesions. Methods A Markov-process model was used to simulate the events following the treatment of a proximal posterior lesion (E2/D1) in a 20-year-old patient in Germany. We compared three interventions (non-invasive; micro-invasive using resin infiltration; invasive using composite restoration). We calculated the risk of complications of initial and possible follow-up treatments and modelled time-dependent non-linear transition probabilities. Costs were calculated based on item-fee catalogues in Germany. Monte-Carlo-microsimulations were performed to compare cost-effectiveness of non- versus micro-invasive treatment and to analyse lifetime costs of all three treatments. Results Micro-invasive treatment was both more costly and more effective than non-invasive therapy, with ceiling-value-thresholds for willingness-to-pay between 16.73 € for E2 and 1.57 € for D1 lesions. Invasive treatment was the most costly strategy. Calculated costs and effectiveness were sensitive to lesion stage, patient’s age, discounting rate and assumed initial treatment costs. Conclusions Non- and micro-invasive treatments have lower long-term costs than invasive therapy of proximal lesions. Micro-invasive therapy had the highest cost-effectiveness for treating D1 lesions in young patients. Decision makers with a willingness-to-pay over 16.73 € and 1.57 € for E2 and D1 lesions, respectively, will find micro-invasive treatment more cost-effective than non-invasive therapy. PMID:24475208

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

The Rendezvous Monitoring Display Capabilities of the Rendezvous and Proximity Operations Program

NASA Technical Reports Server (NTRS)

Brazzel, Jack; Spehar, Pete; Clark, Fred; Foster, Chris; Eldridge, Erin

2013-01-01

The Rendezvous and Proximity Operations Program (RPOP) is a laptop computer- based relative navigation tool and piloting aid that was developed during the Space Shuttle program. RPOP displays a graphical representation of the relative motion between the target and chaser vehicles in a rendezvous, proximity operations and capture scenario. After being used in over 60 Shuttle rendezvous missions, some of the RPOP display concepts have become recognized as a minimum standard for cockpit displays for monitoring the rendezvous task. To support International Space Station (ISS) based crews in monitoring incoming visiting vehicles, RPOP has been modified to allow crews to compare the Cygnus visiting vehicle s onboard navigated state to processed range measurements from an ISS-based, crew-operated Hand Held Lidar sensor. This paper will discuss the display concepts of RPOP that have proven useful in performing and monitoring rendezvous and proximity operations.

Proximate Composition and Nutritional Value of Three Macroalgae: Ascophyllum nodosum, Fucus vesiculosus and Bifurcaria bifurcata

PubMed Central

Agregán, Rubén; Munekata, Paulo E. S.; Carballo, Javier; Şahin, Selin; Lacomba, Ramón

2017-01-01

Proximate composition (moisture, protein, lipid and ash content) and nutritional value (fatty acid, amino acid and mineral profile) of three macroalgae (Ascophyllum nodosum, Fucus vesiculosus and Bifurcaria bifurcate) were studied. Chemical composition was significantly (p < 0.001) different among the three seaweeds. In this regard, the B. bifurcata presented the highest fat content (6.54% of dry matter); whereas, F. vesiculosus showed the highest protein level (12.99% dry matter). Regarding fatty acid content, the polyunsaturated fatty acids (PUFAs) were the most abundant followed by saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs). On the other hand, the three seaweeds are a rich source of K (from 3781.35 to 9316.28 mg/100 g), Mn (from 8.28 to 1.96 mg/100 g), Na (from 1836.82 to 4575.71 mg/100 g) and Ca (from 984.73 to 1160.27 mg/100 g). Finally, the most abundant amino acid was glutamic acid (1874.47–1504.53 mg/100 dry matter), followed by aspartic acid (1677.01–800.84 mg/100 g dry matter) and alanine (985.40–655.73 mg/100 g dry matter). PMID:29140261

Drug transporter expression profiling in a three-dimensional kidney proximal tubule in vitro nephrotoxicity model.

PubMed

Diekjürgen, Dorina; Grainger, David W

2018-05-09

Given currently poor toxicity translational predictions for drug candidates, improved mechanistic understanding underlying nephrotoxicity and drug renal clearance is needed to improve drug development and safety screening. Therefore, better relevant and well-characterized in vitro screening models are required to reliably predict human nephrotoxicity. Because kidney proximal tubules are central to active drug uptake and secretion processes and therefore to nephrotoxicity, this study acquired regio-specific expression data from recently reported primary proximal tubule three-dimensional (3D) hyaluronic acid gel culture and non-gel embedded cultured murine proximal tubule suspensions used in nephrotoxicity assays. Quantitative assessment of the mRNA expression of 21 known kidney tubule markers and important proximal tubule transporters with known roles in drug transport was obtained. Asserting superior gene expression levels over current commonly used two-dimensional (2D) kidney cell culture lines was the study objective. Hence, we compare previously published gel-based 3D proximal tubule fragment culture and their non-gel suspensions for up to 1 week. We demonstrate that 3D tubule culture exhibits superior gene expression levels and profiles compared to published commonly used 2D kidney cell lines (Caki-1 and HK-2) in plastic plate monocultures. Additionally, nearly all tested genes retain mRNA expression after 7 days in both proximal tubule cultures, a limitation of 2D cell culture lines. Importantly, gel presence is shown not to interfere with the gene expression assay. Western blots confirm protein expression of OAT1 and 3 and OCT2. Functional transport assays confirm their respective transporter functions in vitro. Overall, results validate retention of essential toxicity-relevant transporters in this published 3D proximal tubule model over conventional 2D kidney cell cultures, producing opportunities for more reliable, sensitive, and comprehensive drug

3D geometric morphometric analysis of the proximal epiphysis of the hominoid humerus

PubMed Central

Arias-Martorell, Julia; Potau, Josep Maria; Bello-Hellegouarch, Gaëlle; Pastor, Juan Francisco; Pérez-Pérez, Alejandro

2012-01-01

In this study we perform a three-dimensional geometric morphometric (3D GM) analysis of the proximal epiphysis of the humerus in extant great apes, including humans, in order to accurately describe the functional anatomical differences between these taxa. In addition, a fossil hominin specimen of Australopithecus afarensis was included in a multivariate GM analysis in order to test the potential of this methodological approach for making locomotor inferences from fossil remains. The results obtained show significant differences in proximal humeral morphology among the taxa studied, which had thus far largely remained unnoticed. Based on morphofunctional considerations, these anatomical differences can be correlated to differences in the locomotor repertoires of the taxa, thus confirming that the proximal humerus is suitable for constructing paleobiological inferences about locomotion. Modern humans display markedly divergent features, which set them apart from both the extant great apes and the fossil hominin A. afarensis. The morphology of the proximal epiphysis of the humerus of the latter more closely resembles that of the orangutans, thus suggesting that despite hindlimb adaptations to bipedalism, the forelimb of this taxon was still functionally involved in arboreal behaviors, such as climbing or suspension. PMID:22946496

The Effect of Geographical Proximity on Scientific Cooperation among Chinese Cities from 1990 to 2010

PubMed Central

Ma, Haitao; Fang, Chuanglin; Pang, Bo; Li, Guangdong

2014-01-01

Background The relations between geographical proximity and spatial distance constitute a popular topic of concern. Thus, how geographical proximity affects scientific cooperation, and whether geographically proximate scientific cooperation activities in fact exhibit geographic scale features should be investigated. Methodology Selected statistics from the ISI database on cooperatively authored papers, the authors of which resided in 60 typical cites in China, and which were published in the years 1990, 1995, 2000, 2005, and 2010, were used to establish matrices of geographic distance and cooperation levels between cities. By constructing a distance-cooperation model, the degree of scientific cooperation based on spatial distance was calculated. The relationship between geographical proximity and scientific cooperation, as well as changes in that relationship, was explored using the fitting function. Result (1) Instead of declining, the role of geographical proximity in inter-city scientific cooperation has increased gradually but significantly with the popularization of telecommunication technologies; (2) the relationship between geographical proximity and scientific cooperation has not followed a perfect declining curve, and at certain spatial scales, the distance-decay regularity does not work; (3) the Chinese scientific cooperation network gathers around different regional center cities, showing a trend towards a regional network; within this cooperation network the amount of inter-city cooperation occurring at close range increased greatly. Conclusion The relationship between inter-city geographical distance and scientific cooperation has been enhanced and strengthened over time. PMID:25365449

Hereditary motor and sensory neuropathy with proximal predominance (HMSN-P).

PubMed

Campellone, Joseph V

2013-06-01

Hereditary motor and sensory neuropathy with proximal predominance (HMSN-P) is a rare disorder inherited in an autosomal dominant fashion. Patients present with slowly progressive proximal-predominant weakness, painful muscle cramps, fasciculations, large-fiber sensory loss, and areflexia. Electrodiagnostic (EDX) studies typically reveal abnormalities consistent with a sensorimotor neuronopathy. A patient with HMSN-P underwent EDX studies, revealing ongoing and chronic neurogenic denervation, motor unit instability, and neuromyotonic discharges, further defining the spectrum of EDX findings in HMSN-P. The clinical, pathological, and genetic features are also reviewed. The appearance of HMSN-P in the United States and elsewhere calls for clinicians in nonendemic regions to be familiar with this rare disorder, which has typically been geographically confined.

Exploring Characteristics of Retained First-Year Students Enrolled in Non-Proximal Distance Learning Programs

ERIC Educational Resources Information Center

Hillstock, Laurie G.; Havice, Pamela A.

2014-01-01

This study explored pre- and post-admission characteristics of retained first-year students enrolled in non-proximal distance learning programs within public, 2-year colleges. Five pre-admission and six post-admission characteristics were explored. The sample for this study consisted of 197 first-year students enrolled in non-proximal distance…

The place of proximity: social support in mother-adult daughter relationships.

PubMed

Scelza, Brooke A

2011-07-01

The mother-adult daughter relationship has been highlighted in both the social sciences and the public health literature as an important facet of social support networks, particularly as they pertain to maternal and child health. Evolutionary anthropologists also have shown positive associations between support from maternal grandmothers and various outcomes related to reproductive success; however, many of these studies rely on proximity as a surrogate measure of support. Here I present data from the Puerto Rican Maternal and Infant Health Survey (PRMIHS) comparing geographic proximity of mother and daughter with a self-reported measure of mother-to-daughter support. These two measures were used to predict infant health outcomes as well as various measures of instrumental and emotional aid provided during pregnancy and after birth. Primary support was shown to have a positive effect across the analyses, whereas geographic proximity was associated with an increased risk of infant mortality and low birth weight as well as reduced odds of receiving support. This paradox was then examined using a combination variable that teased out the interactions of maternal support and proximity. Women who were geographically close to their mothers but who did not consider them a primary source of support had increased odds of infant death and low birth weight, and were less likely to receive either tangible or intangible forms of aid, while women whose mothers were both close and primary showed uniformly positive outcomes. These results place the role of propinquity within the larger context of social support and highlight the need for more detailed studies of social support within evolutionary anthropology.

Proximity effects across oxide-interfaces of superconductor-insulator-ferromagnet hybrid heterostructure.

PubMed

Prajapat, C L; Singh, Surendra; Bhattacharya, D; Ravikumar, G; Basu, S; Mattauch, S; Zheng, Jian-Guo; Aoki, T; Paul, Amitesh

2018-02-27

A case study of electron tunneling or charge-transfer-driven orbital ordering in superconductor (SC)-ferromagnet (FM) interfaces has been conducted in heteroepitaxial YBa 2 Cu 3 O 7 (YBCO)/La 0.67 Sr 0.33 MnO 3 (LSMO) multilayers interleaved with and without an insulating SrTiO 3 (STO) layer between YBCO and LSMO. X-ray magnetic circular dichroism experiments revealed anti-parallel alignment of Mn magnetic moments and induced Cu magnetic moments in a YBCO/LSMO multilayer. As compared to an isolated LSMO layer, the YBCO/LSMO multilayer displayed a (50%) weaker Mn magnetic signal, which is related to the usual proximity effect. It was a surprise that a similar proximity effect was also observed in a YBCO/STO/LSMO multilayer, however, the Mn signal was reduced by 20%. This reduced magnetic moment of Mn was further verified by depth sensitive polarized neutron reflectivity. Electron energy loss spectroscopy experiment showed the evidence of Ti magnetic polarization at the interfaces of the YBCO/STO/LSMO multilayer. This crossover magnetization is due to a transfer of interface electrons that migrate from Ti (4+)-δ to Mn at the STO/LSMO interface and to Cu 2+ at the STO/YBCO interface, with hybridization via O 2p orbitals. So charge-transfer driven orbital ordering is the mechanism responsible for the observed proximity effect and Mn-Cu anti-parallel coupling in YBCO/STO/LSMO. This work provides an effective pathway in understanding the aspect of long range proximity effect and consequent orbital degeneracy parameter in magnetic coupling.

Adaptive proximate time-optimal servomechanisms - Continuous time case

NASA Technical Reports Server (NTRS)

Workman, M. L.; Kosut, R. L.; Franklin, G. F.

1987-01-01

A Proximate Time-Optimal Servo (PTOS) is developed, along with conditions for its stability. An algorithm is proposed for adapting the PTOS (APTOS) to improve performance in the face of uncertain plant parameters. Under ideal conditions APTOS is shown to be uniformly asymptotically stable. Simulation results demonstrate the predicted performance.

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…

[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.

Proximate and phytochemical of Cola nitida and Cola acuminata.

PubMed

Dewole, E A; Dewumi, D F A; Alabi, J Y T; Adegoke, A

2013-11-15

The aim of the research was to examine Cola nitida and Cola acuminata for their phytochemical and proximate compositions. Presence of secondary metabolites do provide information about the plants for their potentials as a lead candidates for the novel drug discovery. The proximate analysis was done using the method of Association of Official Analytical Chemists (AOAC) and the phytochemical analysis was done using methods of Markkar and Goodchild for tannin, Brunner for saponin, Harbone for alkaloid and Bohm and Koupai-Abyazani for flavonoid. The proximate results showed that the moisture content of Cola acuminata and Cola nitida were in the range of 9.73-9.81%, ash 2.72-2.21%, fat 3.02-2.20%, protein 19.14-15.24%, crude fiber 7.30-4.18% and carbohydrate 58.09 66.45%. Cola acuminate has more protein content, ash and fat than Cola nitida. The result of phytochemical analysis showed that Cola acuminata has more alkaloids (2.22%), tannin (6.46%) and saponin (8.06%) than Cola nitida. The phenol contents of the two kola nuts were the same range 0.27%, the flavonoid were in the range of 0.12-0.14%. The presence of secondary metabolites in these plants are indications that if well researched, novel bioactive compounds can be discovered in them as there are worldwide efforts by scientists looking for new bioactive compounds to combat various ailments which have developed high resistant to already known antibiotics.

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.

The effect of proximity on open-loop accommodation responses measured with pinholes.

PubMed

Morrison, K A; Seidel, D; Strang, N C; Gray, L S

2010-07-01

Open-loop accommodation levels were measured in 41 healthy, young subjects using a Shin-Nippon SRW-5000 autorefractor in the three viewing conditions: a small physical pinhole pupil (SP), an optically projected pinhole in Maxwellian view (MV) and in the dark (DF). The target viewed through the pinholes was a high-contrast letter presented at 0 D vergence in a +5 D Badal lens system. Overall, results showed that SP open-loop accommodation levels were significantly higher than MV and DF levels. Subjects could be divided into two distinct subgroups according to their response behaviour: responders to the proximal effect of the small physical pinhole (SP accommodation > MV accommodation) and non-responders to the proximal effect of the small physical pinhole (SP accommodation approximately MV accommodation). Correlation analysis demonstrated that open-loop accommodation for both pinhole conditions was correlated with DF for the responders, while for the non-responders SP and MV accommodation were correlated, but were not related to DF accommodation. This suggests that under open-loop conditions some individuals' accommodation levels are mainly affected by proximal and cognitive factors (responders) while others are guided primarily by the presence of the more distal target (non-responders). In conclusion, MV reduces the proximal effect of the physical pinhole and produces open-loop accommodation responses which are more consistent than SP and DF responses.

Geographic Proximity of Waterpipe Smoking Establishments to Colleges in the U.S.

PubMed Central

Kates, Frederick R.; Salloum, Ramzi G.; Thrasher, James F.; Islam, Farahnaz; Fleischer, Nancy L.; Maziak, Wasim

2015-01-01

Introduction Waterpipe tobacco smoking is prevalent among college students in the U.S. and increasing in popularity. Waterpipe smoking establishments are almost completely unregulated and limited information exists documenting the expansion of this industry. The objective of this study was to identify U.S.-based waterpipe establishments and measure their proximity to colleges/universities. Methods Waterpipe establishments and their addresses were compiled using five Internet-based directories during 2014 and analyzed in 2015. Addresses were geocoded and overlaid on a U.S. map of accredited colleges/universities. Proximity of colleges/universities to the nearest waterpipe establishment was measured in 3-mile increments. Multinomial logistic regression was used to model the factors associated with proximity of waterpipe establishments to colleges/universities. Results A total of 1,690 waterpipe establishments and 1,454 colleges/universities were included in the study. Overall, 554 colleges/universities (38.1%) were within 3 miles of a waterpipe establishment. Proximity of waterpipe establishments to colleges/universities was associated with higher full-time student enrollment. Public colleges/universities and those with a smoke-free campus policy were at lower odds of having waterpipe establishments within 3 miles of their campuses. Conclusions Waterpipe smoking establishments are more likely to be located near large colleges/universities. This study should inform initiatives aimed at reducing retail tobacco establishment exemptions. PMID:26346294

On blockage effects for a marine hydrokinetic turbine in free surface proximity

NASA Astrophysics Data System (ADS)

Banerjee, A.; Kolekar, N.

2016-12-01

Experimental investigation was carried out with a three-bladed, constant chord marine hydrokinetic turbine to understand the influence of free surface proximity on blockage effects and near wake flow field. The turbine was placed at various depths of immersion as rotational speeds and flow speeds were varied; thrust and torque data was acquired through a submerged thrust torque sensor positioned in-line with the turbine axis. Blockage effects were quantified in terms of changes in power coefficient and were found to be dependent on flow velocity, rotational speed and blade-tip clearence (from free-surface). Flow acceleration near turbine rotation plane was attributed to blockage offered by the rotor, wake, and free surface deformation; the resulting performance improvements were calculated based on the measured thrust values. In addition, stereoscopic particle imaging velocimetry was carried out in the near-wake region using time-averaged and phase-averaged techniques to understand the mechanism responsible for variation of torque (and power coefficient) with rotational speed and free-surface proximity. Flow vizualisation revealed slower wake propagation for higher rotational velocities and increased assymetry in the wake with increasing free surface proximity. Improved performance at high rotational speed was attributed to enhanced wake blockage; performance enhancements with free-surface proximity was attributed to additional blockage effects caused by free surface deformation.

Displaced Proximal Humerus Fractures: is a Sling as Good as a Plate?

PubMed

Steinhaus, Michael E; Dare, David M; Gulotta, Lawrence V

2016-10-01

The treatment of displaced proximal humerus fractures is challenging and complex, as its success is predicated on multiple factors. While it is clear that a majority of proximal humerus fractures may be treated nonoperatively, it is less clear which patients benefit from surgical management. The PROFHER trial, a randomized controlled study, used patient-reported outcomes to compare surgical to nonsurgical management of displaced proximal humerus fractures. The purpose of this review is to highlight the strengths and weaknesses of the PROFHER trial and to assess the validity of its conclusion in the context of existing literature. The authors found no difference in the Oxford Shoulder Score (OSS) between the surgical and nonsurgical groups. Additionally, no difference was found between groups in any of the secondary outcomes, which included the Short-Form 12 (SF-12) health survey, surgical and fracture-related complications, additional surgery or therapy, inpatient medical complications, and mortality. They concluded that the recent increase in surgical management of proximal humerus fractures is perhaps unwarranted. While the randomization was successful and the pragmatic design may enable greater generalizability, this study possesses numerous flaws inherent in such an ambitious endeavor, including an inability to identify specific factors which explain the lack of superiority of surgical management. Despite its weaknesses, this study is a valuable datapoint which encourages surgeons to reexamine their surgical indications for this injury.

Ceramic superconductor/metal composite materials employing the superconducting proximity effect

DOEpatents

Holcomb, Matthew J.

2002-01-01

Superconducting composite materials having particles of superconducting material disposed in a metal matrix material with a high electron-boson coupling coefficient (.lambda.). The superconducting particles can comprise any type of superconductor including Laves phase materials, Chevrel phase materials, A15 compounds, and perovskite cuprate ceramics. The particles preferably have dimensions of about 10-500 nanometers. The particles preferably have dimensions larger than the superconducting coherence length of the superconducting material. The metal matrix material has a .lambda. greater than 0.2, preferably the .lambda. is much higher than 0.2. The metal matrix material is a good proximity superconductor due to its high .lambda.. When cooled, the superconductor particles cause the metal matrix material to become superconducting due to the proximity effect. In cases where the particles and the metal matrix material are chemically incompatible (i.e., reactive in a way that destroys superconductivity), the particles are provided with a thin protective metal coating. The coating is chemically compatible with the particles and metal matrix material. High Temperature Superconducting (HTS) cuprate ceramic particles are reactive and therefore require a coating of a noble metal resistant to oxidation (e.g., silver, gold). The proximity effect extends through the metal coating. With certain superconductors, non-noble metals can be used for the coating.

Mutual proximity graphs for improved reachability in music recommendation

PubMed Central

Flexer, Arthur; Stevens, Jeff

2018-01-01

This paper is concerned with the impact of hubness, a general problem of machine learning in high-dimensional spaces, on a real-world music recommendation system based on visualisation of a k-nearest neighbour (knn) graph. Due to a problem of measuring distances in high dimensions, hub objects are recommended over and over again while anti-hubs are nonexistent in recommendation lists, resulting in poor reachability of the music catalogue. We present mutual proximity graphs, which are an alternative to knn and mutual knn graphs, and are able to avoid hub vertices having abnormally high connectivity. We show that mutual proximity graphs yield much better graph connectivity resulting in improved reachability compared to knn graphs, mutual knn graphs and mutual knn graphs enhanced with minimum spanning trees, while simultaneously reducing the negative effects of hubness. PMID:29348779

Phytochemical investigation and proximate analysis on the leaves of Cnidoscolus aconitifolius.

PubMed

Oyagbemi, Ademola A; Odetola, Adebimpe A; Azeez, Odunayo I

2011-03-01

The study was designed to carry out the phytochemical screening and the proximate analysis of Cnidoscolus aconitifolius leaves. The results obtained showed the presence of tannins, saponin, alkaloids, and flavonoids with the absence of glycosides. The proximate analysis and mineral composition of C. aconitifolius leaves showed high levels of crude protein, ash, and fiber, in that order, and low fat content with concomitant presence of minerals such as sodium, manganese, magnesium, potassium, calcium, iron, phosphate, and zinc. The leaves of C. aconitifolius have high nutrient potentials and could be used as nutraceuticals in complementary foods, especially in sub-Saharan Africa.

Necrosis of the tail of pancreas following proximal splenic artery embolization

PubMed Central

Talving, Peep; Rauk, Mariliis; Vipp, Liisa; Isand, Karl-Gunnar; Šamarin, Aleksandr; Põder, Kalle; Rätsep, Indrek; Saar, Sten

2016-01-01

The current case report presents a rare complication of a significant pancreatic tail necrosis following proximal splenic artery embolization in a 32-year-old male patient involved in a motorcycle accident. Proximal angiographic embolization of the splenic injury after trauma is a widely accepted method with excellent success rate; however, possible complications may occur and has been described in the literature. Nevertheless, only a few case reports pertinent to clinically significant pancreatic tail necrosis after the SAE has been reported. Thus, we add a case report to the scarce literature pertinent to this detrimental and rare complication. PMID:27177891

Formation and function of a new pollen aperture pattern in angiosperms: The proximal sulcus of Tillandsia leiboldiana (Bromeliaceae).

PubMed

Albert, Béatrice; Matamoro-Vidal, Alexis; Raquin, Christian; Nadot, Sophie

2010-02-01

Pollen grains are generally surrounded by an extremely resistant wall interrupted in places by apertures that play a key role in reproduction; pollen tube growth is initiated at these sites. The shift from a proximal to distal aperture location is a striking innovation in seed plant reproduction. Reversals to proximal aperture position have only very rarely been described in angiosperms. The genus Tillandsia belongs to the Bromeliaceae family, and its aperture pattern has been described as distal monosulcate, the most widespread aperture patterns recorded in monocots and basal angiosperms. Here we report developmental and functional elements to demonstrate that the sulcate aperture in Tillandsia leiboldiana is not distal as previously described but proximal. Postmeitotic tetrad observation indicates unambiguously the proximal position of the sulcus, and in vitro germination of pollen grains confirms that the aperture is functional. This is the first report of a sulcate proximal aperture with proximal germination. The observation of microsporogenesis reveals specific features in the patterns of callose thickenings in postmeiotic tetrads.

Noise of a superconducting magnetic flux sensor based on a proximity Josephson junction.

PubMed

Jabdaraghi, R N; Golubev, D S; Pekola, J P; Peltonen, J T

2017-08-14

We demonstrate simultaneous measurements of DC transport properties and flux noise of a hybrid superconducting magnetometer based on the proximity effect (superconducting quantum interference proximity transistor, SQUIPT). The noise is probed by a cryogenic amplifier operating in the frequency range of a few MHz. In our non-optimized device, we achieve minimum flux noise ~4 μΦ 0 /Hz 1/2 , set by the shot noise of the probe tunnel junction. The flux noise performance can be improved by further optimization of the SQUIPT parameters, primarily minimization of the proximity junction length and cross section. Furthermore, the experiment demonstrates that the setup can be used to investigate shot noise in other nonlinear devices with high impedance. This technique opens the opportunity to measure sensitive magnetometers including SQUIPT devices with very low dissipation.

Electrophysiological analysis of bicarbonate permeation across the peritubular cell membrane of rat kidney proximal tubule. II. Exclusion of HCO3(-)-effects on other ion permeabilities and of coupled electroneutral HCO3(-)-transport.

PubMed

Burckhardt, B C; Cassola, A C; Frömter, E

1984-05-01

Cell membrane potentials of rat kidney proximal tubules were measured in response to peritubular ion substitutions in vivo with conventional and Cl- sensitive microelectrodes in order to test possible alternative explanations of the bicarbonate dependent cell potential transients reported in the preceding paper. Significant direct effects of bicarbonate on peritubular K+, Na+, and Cl- conductances could be largely excluded by blocking K+ permeability with Ba2+ and replacing all Na+ and Cl- by choline or respectively SO4(2-) isethionate, or gluconate. Under those conditions the cell membrane response to HCO3- was essentially preserved. In addition it was observed that peritubular Cl- conductance is negligibly small, that Cl-/HCO3- exchange - if present at all - is insignificant, and that rheogenic HCO3- flow with coupling to Na+ flow is also absent or insignificant. A transient disturbance of the Na+ pump or a transient unspecific increase of the membrane permeability was also excluded by experiments with ouabain and by the observation that SITS (4-acetamido-4'-isothiocyano-2,2' disulphonic stilbene) blocked the HCO3- response instantaneously. The data strongly support the notion that the potential changes in response to peritubular HCO3- concentration changes arise from passive rheogenic bicarbonate transfer across the peritubular cell membrane, and hence that this membrane has a high conductance for bicarbonate buffer.

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.

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.

Positional error and time-activity patterns in near-highway proximity studies: an exposure misclassification analysis

PubMed Central

2013-01-01

Background The growing interest in research on the health effects of near-highway air pollutants requires an assessment of potential sources of error in exposure assignment techniques that rely on residential proximity to roadways. Methods We compared the amount of positional error in the geocoding process for three different data sources (parcels, TIGER and StreetMap USA) to a “gold standard” residential geocoding process that used ortho-photos, large multi-building parcel layouts or large multi-unit building floor plans. The potential effect of positional error for each geocoding method was assessed as part of a proximity to highway epidemiological study in the Boston area, using all participants with complete address information (N = 703). Hourly time-activity data for the most recent workday/weekday and non-workday/weekend were collected to examine time spent in five different micro-environments (inside of home, outside of home, school/work, travel on highway, and other). Analysis included examination of whether time-activity patterns were differentially distributed either by proximity to highway or across demographic groups. Results Median positional error was significantly higher in street network geocoding (StreetMap USA = 23 m; TIGER = 22 m) than parcel geocoding (8 m). When restricted to multi-building parcels and large multi-unit building parcels, all three geocoding methods had substantial positional error (parcels = 24 m; StreetMap USA = 28 m; TIGER = 37 m). Street network geocoding also differentially introduced greater amounts of positional error in the proximity to highway study in the 0–50 m proximity category. Time spent inside home on workdays/weekdays differed significantly by demographic variables (age, employment status, educational attainment, income and race). Time-activity patterns were also significantly different when stratified by proximity to highway, with those participants residing in the 0–50 m

Positional error and time-activity patterns in near-highway proximity studies: an exposure misclassification analysis.

PubMed

Lane, Kevin J; Kangsen Scammell, Madeleine; Levy, Jonathan I; Fuller, Christina H; Parambi, Ron; Zamore, Wig; Mwamburi, Mkaya; Brugge, Doug

2013-09-08

The growing interest in research on the health effects of near-highway air pollutants requires an assessment of potential sources of error in exposure assignment techniques that rely on residential proximity to roadways. We compared the amount of positional error in the geocoding process for three different data sources (parcels, TIGER and StreetMap USA) to a "gold standard" residential geocoding process that used ortho-photos, large multi-building parcel layouts or large multi-unit building floor plans. The potential effect of positional error for each geocoding method was assessed as part of a proximity to highway epidemiological study in the Boston area, using all participants with complete address information (N = 703). Hourly time-activity data for the most recent workday/weekday and non-workday/weekend were collected to examine time spent in five different micro-environments (inside of home, outside of home, school/work, travel on highway, and other). Analysis included examination of whether time-activity patterns were differentially distributed either by proximity to highway or across demographic groups. Median positional error was significantly higher in street network geocoding (StreetMap USA = 23 m; TIGER = 22 m) than parcel geocoding (8 m). When restricted to multi-building parcels and large multi-unit building parcels, all three geocoding methods had substantial positional error (parcels = 24 m; StreetMap USA = 28 m; TIGER = 37 m). Street network geocoding also differentially introduced greater amounts of positional error in the proximity to highway study in the 0-50 m proximity category. Time spent inside home on workdays/weekdays differed significantly by demographic variables (age, employment status, educational attainment, income and race). Time-activity patterns were also significantly different when stratified by proximity to highway, with those participants residing in the 0-50 m proximity category reporting significantly

Normal 24-hour ambulatory proximal and distal gastroesophageal reflux parameters in Chinese.

PubMed

Hu, W H C; Wong, N Y H; Lai, K C; Hui, W M; Lam, K F; Wong, B C Y; Xia, H H X; Chan, C K; Chan, A O O; Wong, W M; Tsang, K W T; Lam, S K

2002-06-01

To quantify normal proximal and distal oesophageal acid parameters in healthy Chinese. Observational study. University teaching hospital, Hong Kong. Twenty healthy adults who were not on medication and were free from gastrointestinal symptoms were recruited by advertisement. Ambulatory oesophageal acid (pH<4) exposure parameters were recorded at distal and proximal sites, 5 and 20 cm, respectively above the lower oesophageal sphincter. The 95th percentile for reflux parameters assessed in the distal/proximal oesophagus were: percent total time pH<4, 4.6/0.7%; percent upright time pH<4, 7.0/1.1%; percent supine time pH<4, 4.5/0.5%; number of reflux episodes, 73/12; number of reflux episodes with pH<4 for >5 minutes, 4/0; and the longest single acid exposure episode, 11.2/3.0 minutes. Physiological gastroesophageal reflux occurs in healthy Chinese. These initial data provide a preliminary reference range that could be utilised by laboratories studying Chinese subjects.

Maternal residential proximity to nuclear facilities and low birth weight in offspring in Texas.

PubMed

Gong, Xi; Benjamin Zhan, F; Lin, Yan

2017-03-01

Health effects of close residential proximity to nuclear facilities have been a concern for both the general public and health professionals. Here, a study is reported examining the association between maternal residential proximity to nuclear facilities and low birth weight (LBW) in offspring using data from 1996 through 2008 in Texas, USA. A case-control study design was used together with a proximity-based model for exposure assessment. First, the LBW case/control births were categorized into multiple proximity groups based on distances between their maternal residences and nuclear facilities. Then, a binary logistic regression model was used to examine the association between maternal residential proximity to nuclear facilities and low birth weight in offspring. The odds ratios were adjusted for birth year, public health region of maternal residence, child's sex, gestational weeks, maternal age, education, and race/ethnicity. In addition, sensitivity analyses were conducted for the model. Compared with the reference group (more than 50 km from a nuclear facility), the exposed groups did not show a statistically significant increase in LBW risk [adjusted odds ratio (aOR) 0.91 (95% confidence interval (CI): 0.81, 1.03) for group 40-50 km; aOR 0.98 (CI 0.84, 1.13) for group 30-40 km; aOR 0.95 (CI 0.79, 1.15) for group 20-30 km; aOR 0.86 (CI 0.70, 1.04) for group 10-20 km; and aOR 0.98 (CI 0.59, 1.61) for group 0-10 km]. These results were also confirmed by results of the sensitivity analyses. The results suggest that maternal residential proximity to nuclear facilities is not a significant factor for LBW in offspring.

Effect of a feed/fast protocol on pH in the proximal equine stomach.

PubMed

Husted, L; Sanchez, L C; Baptiste, K E; Olsen, S N

2009-09-01

Risk factors for the development of gastric squamous ulcers include various management procedures, such as intermittent feed deprivation that can occur during weight management regimens or stall and dry lot confinement. To investigate the effect of intermittent feed deprivation relative to continuous feed intake on proximal intragastric pH, specifically in the region of the squamous mucosa of the lesser curvature. In 6 horses, pH electrodes were placed just inside of the oesophageal sphincter in the stomach for each of two 72 h protocols (A and B) in a randomised, cross-over design. Protocol A consisted of 12 h fed, 12 h fasted, 24 h fed and 24 h fasted, in sequence. Protocol B consisted of 72 h fed. During the fed periods of each protocol, horses had ad libitum access to coastal Bermuda hay and were fed sweet feed (1 kg, b.i.d.). Horses had ad libitum access to water at all times. Proximal intragastric pH was significantly lower during protocol A, than during protocol B. However, hourly mean pH was significantly different only during the day and evening hours between protocols. During protocol B, mean proximal pH decreased significantly from 03.00 to 09.00 compared to 19.00 to 23.00 h. A moderate positive correlation of hay intake vs. proximal gastric pH could be established. Intermittent feed deprivation decreased proximal gastric pH in horses relative to those horses for which feed was not restricted. However, the effect was only significant when fasting occurred during the day and evening hours, as a nocturnal decrease in pH occurred simultaneously in the fed horses. Episodes of daytime feed deprivation should be avoided if possible, as proximal gastric acid exposure rapidly increases during such events.

[Proximity and breastfeeding at the maternity hospital].

PubMed

Fradin-Charrier, Anne-Claire

2015-01-01

The establishment of breastfeeding, as well as its duration, are facilitated through the proximity of the mother with her new baby. However, in maternity hospitals, breastfeeding mothers very often leave their baby in the nursery at night time. A study carried out in 2014 in several maternity hospitals put forward suggestions and highlighted areas to improve in everyday practice. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Proximal, distal, and the politics of causation: what's level got to do with it?

PubMed

Krieger, Nancy

2008-02-01

Causal thinking in public health, and especially in the growing literature on social determinants of health, routinely employs the terminology of proximal (or downstream) and distal (or upstream). I argue that the use of these terms is problematic and adversely affects public health research, practice, and causal accountability. At issue are distortions created by conflating measures of space, time, level, and causal strength. To make this case, I draw on an ecosocial perspective to show how public health got caught in the middle of the problematic proximal-distal divide--surprisingly embraced by both biomedical and social determinist frameworks--and propose replacing the terms proximal and distal with explicit language about levels, pathways, and power.

Ventricular shunt tap as a predictor of proximal shunt malfunction in children: a prospective study.

PubMed

Rocque, Brandon G; Lapsiwala, Samir; Iskandar, Bermans J

2008-06-01

The clinical diagnosis of cerebrospinal fluid (CSF) shunt malfunction can be challenging. In this prospective study, the authors evaluated a common method of interrogating shunts: the shunt tap; specifically, its ability to predict proximal malfunction. The authors performed standardized shunt taps in a consecutive series of cases involving children with suspected or proven shunt malfunction, assessing flow and, when possible, opening pressure. Data were collected prospectively, and results analyzed in light of surgical findings. A shunt tap was performed prior to 68 operative explorations in 51 patients. Of the 68 taps, 28 yielded poor or no CSF flow on aspiration. After 26 of these 28 procedures, proximal catheter obstruction was identified. After 28 taps with good CSF return and normal or low opening pressure, 18 shunts were found to have a proximal obstruction, 8 had no obstruction, and 2 had a distal obstruction. Another 12 taps with good CSF flow had high opening pressure; subsequent surgery showed distal obstruction in 11 of the shunts, and proximal obstruction in 1. The positive predictive value of poor flow was 93%, while good flow on shunt tap predicted adequate proximal catheter function in only 55% of cases. Poor flow of CSF on shunt tap is highly predictive of obstruction of the proximal catheter. Because not all patients with good flow on shunt tap underwent surgical shunt exploration, the specificity of this test cannot be determined. Nonetheless, a shunt tap that reveals good flow with a normal opening pressure can be misleading, and management of such cases should be based on clinical judgment.

Sprouty / FGF signaling regulates the proximal-distal feather morphology and the size of dermal papillae

PubMed Central

Yue, Zhicao; Jiang, Ting Xin; Wu, Ping; Widelitz, Randall B; Chuong, Cheng Ming

2013-01-01

In a feather, there are distinct morphologies along the proximal-distal axis. The proximal part is a cylindrical stalk (calamus), whereas the distal part has barb and barbule branches. Here we focus on what molecular signaling activity can modulate feather stem cells to generate these distinct morphologies. We demonstrate the drastic tissue remodeling during feather cycling which includes initiation, growth and resting phases. In the growth phase, epithelial components undergo progressive changes from the collar growth zone to the ramogenic zone, to maturing barb branches along the proximal- distal axis. Mesenchymal components also undergo progressive changes from the dermal papilla, to the collar mesenchyme, to the pulp along the proximal- distal axis. Over-expression of Spry4, a negative regulator of receptor tyrosine kinases, promotes barb branch formation at the expense of the epidermal collar. It even induces barb branches from the follicle sheath (equivalent to the outer root sheath in hair follicles). The results are feathers with expanded feather vane regions and small or missing proximal feather shafts (the calamus). Spry4 also expands the pulp region while reducing the size of dermal papillae, leading to a failure to regenerate. In contrast, over-expressing Fgf10 increases the size of the dermal papillae, expands collar epithelia and mesenchyme, but also prevents feather branch formation and feather keratin differentiation. These results suggest that coordinated Sprouty/FGF pathway activity at different stages is important to modulate feather epidermal stem cells to form distinct feather morphologies along the proximal-distal feather axis. PMID:23000358

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.

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.

Tibial rotational osteotomy for idiopathic torsion. A comparison of the proximal and distal osteotomy levels.

PubMed

Krengel, W F; Staheli, L T

1992-10-01

A retrospective analysis was done of 52 rotational tibial osteotomies (RTOs) performed on 35 patients with severe idiopathic tibial torsion. Thirty-nine osteotomies were performed at the proximal or midtibial level. Thirteen were performed at the distal tibial level with a technique previously described by one of the authors. Serious complications occurred in five (13%) of the proximal and in none of the distal RTOs. For severe and persisting idiopathic tibial torsion, the authors recommend correction by RTO at the distal level. Proximal level osteotomy is indicated only when a varus or valgus deformity required concurrent correction.

Restoring proximal caries lesions conservatively with tunnel restorations

PubMed Central

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

2013-01-01

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

Restoring proximal caries lesions conservatively with tunnel restorations.

PubMed

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

2013-07-30

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

Functional significance of muscarinic receptor expression within the proximal and distal rat vagina.

PubMed

Basha, Maureen; Labelle, Edward F; Northington, Gina M; Wang, Tanchun; Wein, Alan J; Chacko, Samuel

2009-11-01

Information regarding the role of cholinergic nerves in mediating vaginal smooth muscle contraction is sparse, and in vitro studies of the effects of muscarinic agonists on vaginal smooth muscle are discrepant. The goal of this study was to determine the expression of muscarinic receptors in the vaginal wall of the rat. In addition, we sought to determine the effect of the muscarinic receptor agonist carbachol on contractility and inositol phosphate production of the proximal and distal rat vaginal muscularis. RT-PCR analysis indicated that both M(2) and M(3) receptor transcripts were expressed within the proximal and distal rat vagina. Carbachol dose-dependently (10(-7)-10(-4) M) contracted the rat vaginal muscularis with a greater maximal contractile response in the proximal vagina (P < 0.01) compared with the distal vagina. The contractile responses of the rat vaginal muscularis to carbachol were dose dependently inhibited by the M(3) antagonist para-fluoro-hexahydrosiladefenidol, and a pK(B) of 7.78 and 7.95 was calculated for the proximal and distal vagina, respectively. Inositol phosphate production was significantly increased in both regions of the vagina following 20-min exposure to 50 muM carbachol with higher levels detected in the proximal vagina compared with the distal (P < 0.05). Preliminary experiments indicated the presence of M(2) and M(3) receptors in the human vaginal muscularis as well as contraction of human vaginal muscularis to carbachol, indicating that our animal studies are relevant to human tissue. Our results provide strong evidence for the functional significance of M(3) receptor expression in the vaginal muscularis.

Functional significance of muscarinic receptor expression within the proximal and distal rat vagina

PubMed Central

Basha, Maureen; LaBelle, Edward F.; Northington, Gina M.; Wang, Tanchun; Wein, Alan J.

2009-01-01

Information regarding the role of cholinergic nerves in mediating vaginal smooth muscle contraction is sparse, and in vitro studies of the effects of muscarinic agonists on vaginal smooth muscle are discrepant. The goal of this study was to determine the expression of muscarinic receptors in the vaginal wall of the rat. In addition, we sought to determine the effect of the muscarinic receptor agonist carbachol on contractility and inositol phosphate production of the proximal and distal rat vaginal muscularis. RT-PCR analysis indicated that both M2 and M3 receptor transcripts were expressed within the proximal and distal rat vagina. Carbachol dose-dependently (10−7–10−4 M) contracted the rat vaginal muscularis with a greater maximal contractile response in the proximal vagina (P < 0.01) compared with the distal vagina. The contractile responses of the rat vaginal muscularis to carbachol were dose dependently inhibited by the M3 antagonist para-fluoro-hexahydrosiladefenidol, and a pKB of 7.78 and 7.95 was calculated for the proximal and distal vagina, respectively. Inositol phosphate production was significantly increased in both regions of the vagina following 20-min exposure to 50 μM carbachol with higher levels detected in the proximal vagina compared with the distal (P < 0.05). Preliminary experiments indicated the presence of M2 and M3 receptors in the human vaginal muscularis as well as contraction of human vaginal muscularis to carbachol, indicating that our animal studies are relevant to human tissue. Our results provide strong evidence for the functional significance of M3 receptor expression in the vaginal muscularis. PMID:19741053

Correlation between thigh pain and radiological findings with a proximally porous-coated stem.

PubMed

Kinov, Plamen; Radl, Roman; Zacherl, Maximilian; Leithner, Andreas; Windhager, Reinhard

2007-10-01

Thigh pain has been consistently reported with cementless hip arthroplasty. The correlation between thigh pain and radiological findings and the clinical significance of thigh pain have not been studied in any detail. We carried out a retrospective study to analyse the performance of a proximally porous-coated cementless femoral component. Ninety-eight total hip arthroplasties were followed up clinically and radiologically for an average of 33 months (range: 12 to 64) after operation. The clinical results were good or excellent in 85 cases (87%). Thirteen patients (13%) reported thigh pain at latest follow-up. Subsidence of the stem was recorded in 10 cases, cortical thickening occurred in 14 hips (14%), and 17 hips (17%) presented proximal osteopenia. Proximally, radiolucent lines were observed in 11 cases. Thigh pain correlated with radiolucent lines, femoral thickening, fibrous fixation and stem migration. Bone remodelling was noted to continue even five years after implantation. Our observations demonstrated bone ingrowth in the majority of the cases and a low incidence of thigh pain. The correlation between radiological changes and thigh pain suggests implant micromotion and migration in some hips. Patients with thigh pain, changes in the proximal femur and progressive subsidence need further clinical and radiological follow-up.

Social and Spatial Networks: Kinship Distance and Dwelling Unit Proximity in Rural Thailand

PubMed Central

Verdery, Ashton M.; Entwisle, Barbara; Faust, Katherine; Rindfuss, Ronald R.

2013-01-01

We address a long hypothesized relationship between the proximity of individuals' dwelling units and their kinship association. Better understanding this relationship is important because of its implications for contact and association among members of a society. In this paper, we use a unique dataset from Nang Rong, Thailand which contains dwelling unit locations (GPS) and saturated kinship networks of all individuals living in 51 agricultural villages. After presenting arguments for a relationship between individuals’ dwelling unit locations and their kinship relations as well as the particulars of our case study, we introduce the data and describe our analytic approach. We analyze how kinship - considered as both a system linking collections of individuals in an extended kinship network and as dyadic links between pairs of individuals -patterns the proximity of dwelling units in rural villages. The results show that in general, extended kin live closer to one another than do unrelated individuals. Further, the degree of relatedness between kin correlates with the distance between their dwelling units. Close kin are more likely to co-reside, a fact which drives much of the relationship between kinship relatedness and dwelling unit proximity within villages. There is nevertheless suggestive evidence of a relationship between kinship association and dwelling unit proximity among kin who do not live together. PMID:23956489

Paradoxical activation of the sodium chloride cotransporter (NCC) without hypertension in kidney deficient in a regulatory subunit of Na,K-ATPase, FXYD2.

PubMed

Arystarkhova, Elena; Ralph, Donna L; Liu, Yi Bessie; Bouley, Richard; McDonough, Alicia A; Sweadner, Kathleen J

2014-12-01

Na,K-ATPase generates the driving force for sodium reabsorption in the kidney. Na,K-ATPase functional properties are regulated by small proteins belonging to the FXYD family. In kidney FXYD2 is the most abundant: it is an inhibitory subunit expressed in almost every nephron segment. Its absence should increase sodium pump activity and promote Na(+) retention, however, no obvious renal phenotype was detected in mice with global deletion of FXYD2 (Arystarkhova et al. 2013). Here, increased total cortical Na,K-ATPase activity was documented in the Fxyd2(-/-) mouse, without increased α1β1 subunit expression. We tested the hypothesis that adaptations occur in distal convoluted tubule (DCT), a major site of sodium adjustments. Na,K-ATPase immunoreactivity in DCT was unchanged, and there was no DCT hypoplasia. There was a marked activation of thiazide-sensitive sodium chloride cotransporter (NCC; Slc12a3) in DCT, predicted to increase Na(+) reabsorption in this segment. Specifically, NCC total increased 30% and NCC phosphorylated at T53 and S71, associated with activation, increased 4-6 fold. The phosphorylation of the closely related thick ascending limb (TAL) apical NKCC2 (Slc12a1) increased at least twofold. Abundance of the total and cleaved (activated) forms of ENaC α-subunit was not different between genotypes. Nonetheless, no elevation of blood pressure was evident despite the fact that NCC and NKCC2 are in states permissive for Na(+) retention. Activation of NCC and NKCC2 may reflect an intracellular linkage to elevated Na,K-ATPase activity or a compensatory response to Na(+) loss proximal to the TAL and DCT. © 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Management of proximal interphalangeal joint injuries

PubMed Central

Freiberg, Arnis

2007-01-01

Injuries to the proximal interphalangeal joint are common but frequently missed. They are often overtreated by prolonged immobilization, resulting in stiffness, which may be permanent. The purpose of the present article is to briefly review the relevant anatomy and biomechanics, present an approach to physical examination and diagnosis, and propose a practical clinical classification. The treatment of the most severe injury – the intra-articular fracture dislocation – is controversial. The various treatment options are discussed, based on personal experience and a review of the literature. A list of relevant references is presented. PMID:19554177

Geographic density and proximity of vape shops to colleges in the USA.

PubMed

Dai, Hongying; Hao, Jianqiang

2017-07-01

Vape shops have been spreading rapidly in the USA since 2008, catering to the fast-growing market for electronic cigarettes. Little is known about the geographic density and proximity of vape shops near colleges. Names and addresses of vape shops were collected from 3 online directories: Yelp.com, Yellowpages.com and Guidetovaping.com. We identified the prevalence of US-based vape shops and their density and proximity to colleges using a geographic information system. General linear model and negative binomial regression were performed to examine the factors associated with proximity and density of vape shops near colleges. We identified 9945 vape shops in the USA as of December 2015, a nearly threefold increase from 2013. Among the 2755 colleges included in this study, 66.5% had at least 1 vape shop within a 3-mile radius. The median proximity of the nearest vape shop to each college/university was 1.8 miles. Proximity increased by student population, private as compared to public institutions, and location (city vs rural). Within a 1-mile radius, colleges with smoke-free campus policies had a lower density of vape shops (RR=0.6, p=0.002) than those without smoke-free campus policies. Private institutions had a higher density of vape shops (RR=7.8, p<0.0001) than did public institutions. Colleges with campus housing had a lower density of vape shops (RR=0.4, p<0.0001) than those without campus housing, and colleges located in cities had a much higher density of vape shops than those located in rural areas (RR=6.6, p<0.0001). Smoke-free and e-cigarette-free campus policies had significant interactions with college type (private vs public) and campus housing in reducing vape shop density. Vape shops are more likely to be located near private institutions and colleges in cities as opposed to rural areas. Smoke-free and e-cigarette-free campus policies have had significant effects in reducing the density of vape shops but have not reduced the proximity of vape shops

Challenges of anamorphic high-NA lithography and mask making

NASA Astrophysics Data System (ADS)

Hsu, Stephen D.; Liu, Jingjing

2017-06-01

Chip makers are actively working on the adoption of 0.33 numerical aperture (NA) EUV scanners for the 7-nm and 5-nm nodes (B. Turko, S. L. Carson, A. Lio, T. Liang, M. Phillips, et al., in `Proc. SPIE9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 977602 (2016) doi: 10.1117/12.2225014; A. Lio, in `Proc. SPIE9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 97760V (2016) doi: 10.1117/12.2225017). In the meantime, leading foundries and integrated device manufacturers are starting to investigate patterning options beyond the 5-nm node (O. Wood, S. Raghunathan, P. Mangat, V. Philipsen, V. Luong, et al., in `Proc. SPIE. 9422, Extreme Ultraviolet (EUV) Lithography VI', vol. 94220I (2015) doi: 10.1117/12.2085022). To minimize the cost and process complexity of multiple patterning beyond the 5-nm node, EUV high-NA single-exposure patterning is a preferred method over EUV double patterning (O. Wood, S. Raghunathan, P. Mangat, V. Philipsen, V. Luong, et al., in `Proc. SPIE. 9422, Extreme Ultraviolet (EUV) Lithography VI', vol. 94220I (2015) doi: 10.1117/12.2085022; J. van Schoot, K. van Ingen Schenau, G. Bottiglieri, K. Troost, J. Zimmerman, et al., `Proc. SPIE. 9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 97761I (2016) doi: 10.1117/12.2220150). The EUV high-NA scanner equipped with a projection lens of 0.55 NA is designed to support resolutions below 10 nm. The high-NA system is beneficial for enhancing resolution, minimizing mask proximity correction bias, improving normalized image log slope (NILS), and controlling CD uniformity (CDU). However, increasing NA from 0.33 to 0.55 reduces the depth of focus (DOF) significantly. Therefore, the source mask optimization (SMO) with sub-resolution assist features (SRAFs) are needed to increase DOF to meet the demanding full chip process control requirements (S. Hsu, R. Howell, J. Jia, H.-Y. Liu, K. Gronlund, et al., EUV `Proc. SPIE9048, Extreme Ultraviolet (EUV) Lithography VI', (2015) doi: 10

Risk of limb birth defects and mother's home proximity to cornfields.

PubMed

Ochoa-Acuña, Hugo; Carbajo, Cristina

2009-07-15

Although previous studies have linked proximity to crops and birth defects, they lacked individual-level exposure data and none was based on using planted area instead of linear proximity to crops as the exposure metric. We studied birth defects in relation to the area of corn or soybeans within 500 m of the mother's residence. We selected all singleton births from rural areas conceived during the 2000-2004 spring-summer months (n=48,216). We determined whether the area with corn or soybeans around the home was associated with birth defects using multiple unconditional logistic regression. We found that limb birth defects (ICD-9-CM 754.5, 755) increased in relation to cornfields (Adjusted OR=1.22; 95 % CI=1.01, 1.47 per additional 10 ha planted with corn within 500 m). None of the birth defect types studied was associated with soybeans. In the Midwest, a significant and expanding proportion of the population is now living in close proximity to cornfields. Our results suggest that additional studies should be conducted to identify which factor(s) associated with cornfields are behind the observed increase in limb birth defects.

Grouper tshβ Promoter-Driven Transgenic Zebrafish Marks Proximal Kidney Tubule Development

PubMed Central

Wang, Yang; Sun, Zhi-Hui; Zhou, Li; Li, Zhi; Gui, Jian-Fang

2014-01-01

Kidney tubule plays a critical role in recovering or secreting solutes, but the detailed morphogenesis remains unclear. Our previous studies have found that grouper tshβ (gtshβ) is also expressed in kidney, however, the distribution significance is still unknown. To understand the gtshβ role and kidney tubule morphogenesis, here, we have generated a transgenic zebrafish line Tg(gtshβ:GFP) with green fluorescent protein driven by the gtshβ promoter. Similar to the endogenous tshβ in zebrafish or in grouper, the gtshβ promoter-driven GFP is expressed in pituitary and kidney, and the developing details of proximal kidney tubule are marked in the transgenic zebrafish line. The gfp initially transcribes at 16 hours post fertilization (hpf) above the dorsal mesentery, and partially co-localizes with pronephric tubular markers slc20a1a and cdh17. Significantly, the GFP specifically localizes in proximal pronephric segments during embryogenesis and resides at kidney duct epithelium in adult fish. To test whether the gtshβ promoter-driven GFP may serve as a readout signal of the tubular development, we have treated the embryos with retinoic acid signaing (RA) reagents, in which exogenous RA addition results in a distal extension of the proximal segments, while RA inhibition induces a weakness and shortness of the proximal segments. Therefore, this transgenic line provides a useful tool for genetic or chemical analysis of kidney tubule. PMID:24905828

Neurogenic and myogenic motor patterns of rabbit proximal, mid, and distal colon.

PubMed

Dinning, P G; Costa, M; Brookes, S J; Spencer, N J

2012-07-01

The rabbit colon consists of four distinct regions. The motility of each region is controlled by myogenic and neurogenic mechanisms. Associating these mechanisms with specific motor patterns throughout all regions of the colon has not previously been achieved. Three sections of the colon (the proximal, mid, and distal colon) were removed from euthanized rabbits. The proximal colon consists of a triply teniated region and a single tenia region. Spatio-temporal maps were constructed from video recordings of colonic wall diameter, with associated intraluminal pressure recorded from the aboral end. Hexamethonium (100 μM) and tetrodotoxin (TTX; 0.6 μM) were used to inhibit neural activity. Four distinct patterns of motility were detected: 1 myogenic and 3 neurogenic. The myogenic activity consisted of circular muscle (CM) contractions (ripples) that occurred throughout the colon and propagated in both antegrade (anal) and retrograde (oral) directions. The neural activity of the proximal colon consisted of slowly (0.1 mm/s) propagating colonic migrating motor complexes, which were abolished by hexamethonium. These complexes were observed in the region of the proximal colon with a single band of tenia. In the distal colon, tetrodotoxin-sensitive, thus neurally mediated, but hexamethonium-resistant, peristaltic (anal) and antiperistaltic (oral) contractions were identified. The distinct patterns of neurogenic and myogenic motor activity recorded from isolated rabbit colon are specific to each anatomically distinct region. The regional specificity motor pattern is likely to facilitate orderly transit of colonic content from semi-liquid to solid composition of feces.

There's more to food store choice than proximity: a questionnaire development study.

PubMed

Krukowski, Rebecca A; Sparks, Carla; DiCarlo, Marisha; McSweeney, Jean; West, Delia Smith

2013-06-17

Proximity of food stores is associated with dietary intake and obesity; however, individuals frequently shop at stores that are not the most proximal. Little is known about other factors that influence food store choice. The current research describes the development of the Food Store Selection Questionnaire (FSSQ) and describes preliminary results of field testing the questionnaire. Development of the FSSQ involved a multidisciplinary literature review, qualitative analysis of focus group transcripts, and expert and community reviews. Field testing consisted of 100 primary household food shoppers (93% female, 64% African American), in rural and urban Arkansas communities, rating FSSQ items as to their importance in store choice and indicating their top two reasons. After eliminating 14 items due to low mean importance scores and high correlations with other items, the final FSSQ questionnaire consists of 49 items. Items rated highest in importance were: meat freshness; store maintenance; store cleanliness; meat varieties; and store safety. Items most commonly rated as top reasons were: low prices; proximity to home; fruit/vegetable freshness; fruit/vegetable variety; and store cleanliness. The FSSQ is a comprehensive questionnaire for detailing key reasons in food store choice. Although proximity to home was a consideration for participants, there were clearly other key factors in their choice of a food store. Understanding the relative importance of these different dimensions driving food store choice in specific communities may be beneficial in informing policies and programs designed to support healthy dietary intake and obesity prevention.

Attitude Determination and Control System Design for a 6U Cube Sat for Proximity Operations and Rendezvous

DTIC Science & Technology

2014-08-04

Resident Space Object Proximity Analysis and IMAging) mission is carried out by a 6U Cube Sat class satellite equipped with a warm gas propulsion system... mission . The ARAPAIMA (Application for Resident Space Object Proximity Analysis and IMAging) mission is carried out by a 6 U CubeSat class satellite...attitude determination and control subsystem (ADCS) (or a proximity operation and imaging satellite mission . The ARAP AI MA (Application for

Management bone loss of the proximal femur in revision hip arthroplasty: Update on reconstructive options

PubMed Central

Sakellariou, Vasileios I; Babis, George C

2014-01-01

The number of revision total hip arthroplasties is expected to rise as the indications for arthroplasty will expand due to the aging population. The prevalence of extensive proximal femoral bone loss is expected to increase subsequently. The etiology of bone loss from the proximal femur after total hip arthroplasty is multifactorial. Stress shielding, massive osteolysis, extensive loosening and history of multiple surgeries consist the most common etiologies. Reconstruction of extensive bone loss of the proximal femur during a revision hip arthroplasty is a major challenge for even the most experienced orthopaedic surgeon. The amount of femoral bone loss and the bone quality of the remaining metaphyseal and diaphyseal bone dictate the selection of appropriate reconstructive option. These include the use of impaction allografting, distal press-fit fixation, allograft-prosthesis composites and tumor megaprostheses. This review article is a concise review of the current literature and provides an algorithmic approach for reconstruction of different types of proximal femoral bone defects. PMID:25405090

Lithographic process window optimization for mask aligner proximity lithography

NASA Astrophysics Data System (ADS)

Voelkel, Reinhard; Vogler, Uwe; Bramati, Arianna; Erdmann, Andreas; Ünal, Nezih; Hofmann, Ulrich; Hennemeyer, Marc; Zoberbier, Ralph; Nguyen, David; Brugger, Juergen

2014-03-01

We introduce a complete methodology for process window optimization in proximity mask aligner lithography. The commercially available lithography simulation software LAB from GenISys GmbH was used for simulation of light propagation and 3D resist development. The methodology was tested for the practical example of lines and spaces, 5 micron half-pitch, printed in a 1 micron thick layer of AZ® 1512HS1 positive photoresist on a silicon wafer. A SUSS MicroTec MA8 mask aligner, equipped with MO Exposure Optics® was used in simulation and experiment. MO Exposure Optics® is the latest generation of illumination systems for mask aligners. MO Exposure Optics® provides telecentric illumination and excellent light uniformity over the full mask field. MO Exposure Optics® allows the lithography engineer to freely shape the angular spectrum of the illumination light (customized illumination), which is a mandatory requirement for process window optimization. Three different illumination settings have been tested for 0 to 100 micron proximity gap. The results obtained prove, that the introduced process window methodology is a major step forward to obtain more robust processes in mask aligner lithography. The most remarkable outcome of the presented study is that a smaller exposure gap does not automatically lead to better print results in proximity lithography - what the "good instinct" of a lithographer would expect. With more than 5'000 mask aligners installed in research and industry worldwide, the proposed process window methodology might have significant impact on yield improvement and cost saving in industry.

Acidosis Differentially Modulates Inactivation in NaV1.2, NaV1.4, and NaV1.5 Channels

PubMed Central

Vilin, Yury Y.; Peters, Colin H.; Ruben, Peter C.

2012-01-01

NaV channels play a crucial role in neuronal and muscle excitability. Using whole-cell recordings we studied effects of low extracellular pH on the biophysical properties of NaV1.2, NaV1.4, and NaV1.5, expressed in cultured mammalian cells. Low pH produced different effects on different channel subtypes. Whereas NaV1.4 exhibited very low sensitivity to acidosis, primarily limited to partial block of macroscopic currents, the effects of low pH on gating in NaV1.2 and NaV1.5 were profound. In NaV1.2 low pH reduced apparent valence of steady-state fast inactivation, shifted the τ(V) to depolarizing potentials and decreased channels availability during onset to slow and use-dependent inactivation (UDI). In contrast, low pH delayed open-state inactivation in NaV1.5, right-shifted the voltage-dependence of window current, and increased channel availability during onset to slow and UDI. These results suggest that protons affect channel availability in an isoform-specific manner. A computer model incorporating these results demonstrates their effects on membrane excitability. PMID:22701426

Self-expanding metallic stents drainage for acute proximal colon obstruction

PubMed Central

Yao, Li-Qin; Zhong, Yun-Shi; Xu, Mei-Dong; Xu, Jian-Min; Zhou, Ping-Hong; Cai, Xian-Li

2011-01-01

AIM: To clarify the usefulness of the self-expanding metallic stents (SEMS) in the management of acute proximal colon obstruction due to colon carcinoma before curative surgery. METHODS: Eighty-one colon (proximal to spleen flex) carcinoma patients (47 males and 34 females, aged 18-94 years, mean = 66.2 years) treated between September 2004 and June 2010 for acute colon obstruction were enrolled to this study, and their clinical and radiological features were reviewed. After a cleaning enema was administered, urgent colonoscopy was performed. Subsequently, endoscopic decompression using SEMS placement was attempted. RESULTS: Endoscopic decompression using SEMS placement was technically successful in 78 (96.3%) of 81 patients. Three patients’ symptoms could not be relieved after SEMS placement and emergent operation was performed 1 d later. The site of obstruction was transverse colon in 18 patients, the hepatic flex in 42, and the ascending colon in 21. Following adequate cleansing of the colon, patients’ abdominal girth was decreased from 88 ± 3 cm before drainage to 72 ± 6 cm 7 d later, and one-stage surgery after 8 ± 1 d (range, 7-10 d) was performed. No anastomotic leakage or postoperative stenosis occurred after operation. CONCLUSION: SEMS placement is effective and safe in the management of acute proximal colon obstruction due to colon carcinoma, and is considered as a bridged method before curative surgery. PMID:21876623

Exploring the Structure of the Voltage-gated Na+ Channel by an Engineered Drug Access Pathway to the Receptor Site for Local Anesthetics*

PubMed Central

Lukacs, Peter; Gawali, Vaibhavkumar S.; Cervenka, Rene; Ke, Song; Koenig, Xaver; Rubi, Lena; Zarrabi, Touran; Hilber, Karlheinz; Stary-Weinzinger, Anna; Todt, Hannes

2014-01-01

Despite the availability of several crystal structures of bacterial voltage-gated Na+ channels, the structure of eukaryotic Na+ channels is still undefined. We used predictions from available homology models and crystal structures to modulate an external access pathway for the membrane-impermeant local anesthetic derivative QX-222 into the internal vestibule of the mammalian rNaV1.4 channel. Potassium channel-based homology models predict amino acid Ile-1575 in domain IV segment 6 to be in close proximity to Lys-1237 of the domain III pore-loop selectivity filter. The mutation K1237E has been shown previously to increase the diameter of the selectivity filter. We found that an access pathway for external QX-222 created by mutations of Ile-1575 was abolished by the additional mutation K1237E, supporting the notion of a close spatial relationship between sites 1237 and 1575. Crystal structures of bacterial voltage-gated Na+ channels predict that the side chain of rNaV1.4 Trp-1531 of the domain IV pore-loop projects into the space between domain IV segment 6 and domain III pore-loop and, therefore, should obstruct the putative external access pathway. Indeed, mutations W1531A and W1531G allowed for exceptionally rapid access of QX-222. In addition, W1531G created a second non-selective ion-conducting pore, bypassing the outer vestibule but probably merging into the internal vestibule, allowing for control by the activation gate. These data suggest a strong structural similarity between bacterial and eukaryotic voltage-gated Na+ channels. PMID:24947510

Spain, The European Union and the United States in the Age of Terror: Spanish Strategic Culture and the Global War on Terror

DTIC Science & Technology

2004-06-01

Fascists (Falange Espanola); the Radical Right : Carlists (Catholic Corporatism) and Renovación Española (Authoritarian Monarchists) and neo-authoritarian...period from 1933-1936, CEDA remained the largest political party in Spain followed by the Radical Right groups of Carlists and traditional monarchists of...31 The driving force towards authoritarianism in Spain was the radical right platform developed by Jose Calvo Sotelo. Prior to the Civil War

Proximal and Overall Gastric Emptying of Solids in Patients with Reduced Gastric Volume Accommodation Compared to Matched Controls

PubMed Central

Camilleri, Michael; Breen, Mary; Ryks, Michael; Burton, Duane

2011-01-01

Background Interventions such as gastric surgery and erythromycin result in displacement of solids to the distal stomach and acceleration of overall and proximal gastric emptying. The effect of non-surgical impairment of gastric accommodation on gastric emptying is unclear. Non-surgical impairment of gastric accommodation is associated with accelerated gastric emptying. Aim To compare measurements of proximal and overall gastric emptying in patients with reduced postprandial gastric volume accommodation with the emptying rates in age- and gender-matched controls with normal postprandial gastric volume accommodation. Methods We evaluated overall and proximal gastric emptying in 9 patients with impaired gastric accommodation and age-equivalent and gender-matched controls. Gastric volumes and emptying were measured using validated SPECT and dual gamma camera scintigraphy respectively. We compared group differences in overall and proximal gastric emptying t1/2 by t test. Results Patients with impaired postprandial gastric volume accommodation had greater fasting gastric volume. The proportion of food emptied from the proximal stomach immediately after meal ingestion was lower and t1/2of proximal gastric emptying correspondingly longer in the group with reduced postprandial gastric accommodation. In contrast, differences were not detected in overall gastric emptying in the two groups, and the ratio of overall to proximal gastric emptying t1/2was greater in the group with impaired volume accommodation. Conclusions Proximal stomach emptying is reduced in patients with impaired postprandial volume accommodation; this difference occurs predominantly during the time of meal ingestion. Compensatory mechanisms that result in normal overall gastric emptying require further elucidation. PMID:21327917

A Different Method of Hepaticojejunostomy for Proximal Biliary Injuries

PubMed Central

Schaefer, Glennon

1996-01-01

The management of proximal biliary injuries presents a surgical challenge. Anastomoses can be difficult to perform and can have poor results. We describe a method of hepaticojejunostomy done from within the Roux-en-Y loop, which can be utilized in this situation. PMID:9184866

Variability of United States Online Rehabilitation Protocols for Proximal Hamstring Tendon Repair.

PubMed

Lightsey, Harry M; Kantrowitz, David E; Swindell, Hasani W; Trofa, David P; Ahmad, Christopher S; Lynch, T Sean

2018-02-01

The optimal postoperative rehabilitation protocol following repair of complete proximal hamstring tendon ruptures is the subject of ongoing investigation, with a need for more standardized regimens and evidence-based modalities. To assess the variability across proximal hamstring tendon repair rehabilitation protocols published online by United States (US) orthopaedic teaching programs. Cross-sectional study. Online proximal hamstring physical therapy protocols from US academic orthopaedic programs were reviewed. A web-based search using the search term complete proximal hamstring repair rehabilitation protocol provided an additional 14 protocols. A comprehensive scoring rubric was developed after review of all protocols and was used to assess each protocol for both the presence of various rehabilitation components and the point at which those components were introduced. Of 50 rehabilitation protocols identified, 35 satisfied inclusion criteria and were analyzed. Twenty-five protocols (71%) recommended immediate postoperative bracing: 12 (34%) prescribed knee bracing, 8 (23%) prescribed hip bracing, and 5 (14%) did not specify the type of brace recommended. Fourteen protocols (40%) advised immediate nonweightbearing with crutches, while 16 protocols (46%) permitted immediate toe-touch weightbearing. Advancement to full weightbearing was allowed at a mean of 7.1 weeks (range, 4-12 weeks). Most protocols (80%) recommended gentle knee and hip passive range of motion and active range of motion, starting at a mean 1.4 weeks (range, 0-3 weeks) and 4.0 weeks (range, 0-6 weeks), respectively. However, only 6 protocols (17%) provided specific time points to initiate full hip and knee range of motion: a mean 8.0 weeks (range, 4-12 weeks) and 7.8 weeks (range, 0-12 weeks), respectively. Considerable variability was noted in the inclusion and timing of strengthening, stretching, proprioception, and cardiovascular exercises. Fifteen protocols (43%) required completion of

3D Proximal Tubule Tissues Recapitulate Key Aspects of Renal Physiology to Enable Nephrotoxicity Testing

PubMed Central

King, Shelby M.; Higgins, J. William; Nino, Celina R.; Smith, Timothy R.; Paffenroth, Elizabeth H.; Fairbairn, Casey E.; Docuyanan, Abigail; Shah, Vishal D.; Chen, Alice E.; Presnell, Sharon C.; Nguyen, Deborah G.

2017-01-01

Due to its exposure to high concentrations of xenobiotics, the kidney proximal tubule is a primary site of nephrotoxicity and resulting attrition in the drug development pipeline. Current pre-clinical methods using 2D cell cultures and animal models are unable to fully recapitulate clinical drug responses due to limited in vitro functional lifespan, or species-specific differences. Using Organovo's proprietary 3D bioprinting platform, we have developed a fully cellular human in vitro model of the proximal tubule interstitial interface comprising renal fibroblasts, endothelial cells, and primary human renal proximal tubule epithelial cells to enable more accurate prediction of tissue-level clinical outcomes. Histological characterization demonstrated formation of extensive microvascular networks supported by endogenous extracellular matrix deposition. The epithelial cells of the 3D proximal tubule tissues demonstrated tight junction formation and expression of renal uptake and efflux transporters; the polarized localization and function of P-gp and SGLT2 were confirmed. Treatment of 3D proximal tubule tissues with the nephrotoxin cisplatin induced loss of tissue viability and epithelial cells in a dose-dependent fashion, and cimetidine rescued these effects, confirming the role of the OCT2 transporter in cisplatin-induced nephrotoxicity. The tissues also demonstrated a fibrotic response to TGFβ as assessed by an increase in gene expression associated with human fibrosis and histological verification of excess extracellular matrix deposition. Together, these results suggest that the bioprinted 3D proximal tubule model can serve as a test bed for the mechanistic assessment of human nephrotoxicity and the development of pathogenic states involving epithelial-interstitial interactions, making them an important adjunct to animal studies. PMID:28337147

Performance of Encounternet Tags: Field Tests of Miniaturized Proximity Loggers for Use on Small Birds

PubMed Central

Levin, Iris I.; Zonana, David M.; Burt, John M.; Safran, Rebecca J.

2015-01-01

Proximity logging is a new tool for understanding social behavior as it allows for accurate quantification of social networks. We report results from field calibration and deployment tests of miniaturized proximity tags (Encounternet), digital transceivers that log encounters between tagged individuals. We examined radio signal behavior in relation to tag attachment (tag, tag on bird, tag on saline-filled balloon) to understand how radio signal strength is affected by the tag mounting technique used for calibration tests. We investigated inter-tag and inter-receiver station variability, and in each calibration test we accounted for the effects of antennae orientation. Additionally, we used data from a live deployment on breeding barn swallows (Hirundo rustica erythrogaster) to analyze the quality of the logs, including reciprocal agreement in dyadic logs. We evaluated the impact (in terms of mass changes) of tag attachment on the birds. We were able to statistically distinguish between RSSI values associated with different close-proximity (<5m) tag-tag distances regardless of antennae orientation. Inter-tag variability was low, but we did find significant inter-receiver station variability. Reciprocal agreement of dyadic logs was high and social networks were constructed from proximity tag logs based on two different RSSI thresholds. There was no evidence of significant mass loss in the time birds were wearing tags. We conclude that proximity loggers are accurate and effective for quantifying social behavior. However, because RSSI and distance cannot be perfectly resolved, data from proximity loggers are most appropriate for comparing networks based on specific RSSI thresholds. The Encounternet system is flexible and customizable, and tags are now light enough for use on small animals (<50g). PMID:26348329

The relationship between residential proximity to extremely low frequency power transmission lines and adverse birth outcomes.

PubMed

Auger, Nathalie; Joseph, Dominique; Goneau, Marc; Daniel, Mark

2011-01-01

Occupational exposure to electromagnetic fields has been linked to adverse birth outcomes. This study evaluated whether maternal residential proximity to power transmission lines was associated with adverse birth outcomes. Live singleton births in the Montréal and Québec census metropolitan areas from 1990 to 2004 were extracted from the Québec birth file (N=707,215). Proximity was defined as residing within 400 m of a transmission line. Generalised estimating equations were used to evaluate associations between residential proximity to transmission lines and preterm birth (PTB), low birth weight (LBW), small-for-gestational age (SGA) birth and infant sex, accounting for maternal age, education, marital status, ethnicity, parity, period of birth, and neighbourhood median household income. There was no association between residential proximity to transmission lines and PTB, LBW and infant sex in unadjusted and adjusted models. A lower likelihood of SGA birth was present for some distance categories (eg, adjusted OR 0.88, 95% CI 0.81 to 0.95 for 50-75 m relative to ≥400 m). Residential proximity to transmission lines is not associated with adverse births outcomes.

Floor Proximity Emergency Escape Path Marking Systems Incorporating Photoluminescent Elements

DOT National Transportation Integrated Search

1997-07-24

This advisory circular (AC) provides guidance material for use in demonstrating : compliance with the provisions of part 25 of the Federal Aviation Regulations : (FAR) regarding floor proximity emergency escape path marking systems (FPEEPMS) : which ...

A geometric reappraisal of proximal landing zones for thoracic endovascular aortic repair according to aortic arch types.

PubMed

Marrocco-Trischitta, Massimiliano M; de Beaufort, Hector W; Secchi, Francesco; van Bakel, Theodorus M; Ranucci, Marco; van Herwaarden, Joost A; Moll, Frans L; Trimarchi, Santi

2017-06-01

This study assessed whether the additional use of the aortic arch classification in type I, II, and III may complement Ishimaru's aortic arch map and provide valuable information on the geometry and suitability of proximal landing zones for thoracic endovascular aortic repair. Anonymized thoracic computed tomography scans of healthy aortas were reviewed and stratified according to the aortic arch classification, and 20 of each type of arch were selected. Further processing allowed calculation of angulation and tortuosity of each proximal landing zone. Data were described indicating both proximal landing zone and type of arch (eg, 0/I). Angulation was severe (>60°) in 2/III and in 3/III. Comparisons among the types of arch showed an increase in proximal landing zones angulation (P < .001) and tortuosity (P = .009) depending on the type of arch. Comparisons within type of arch showed no change in angulation and tortuosity across proximal landing zones within type I arch (P = .349 and P = .409), and increases in angulation and tortuosity toward more distal proximal landing zones within type II (P = .003 and P = .043) and type III (P < .001 in both). The aortic arch classification is associated with a consistent geometric pattern of the aortic arch map, which identifies specific proximal landing zones with suboptimal angulation for stent graft deployment. Arches II and III also appear to have progressively less favorable anatomy for thoracic endovascular aortic repair compared with arch I. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Gross anatomical and dimensional characteristics of the proximal hamstring origin.

PubMed

Feucht, Matthias J; Plath, Johannes E; Seppel, Gernot; Hinterwimmer, Stefan; Imhoff, Andreas B; Brucker, Peter U

2015-09-01

The current study was undertaken to better define the gross anatomical and dimensional characteristics of the proximal hamstring origin. Twelve paired whole-lower extremities from six embalmed cadavers were dissected. The gross anatomy of the proximal hamstrings was studied. With the tendons attached to the ischial tuberosity, the width and thickness of each tendon was measured 1 cm distally to their origin, and the distance from the most proximal border of the common origin of the semitendinosus (ST) and long head of the biceps (LB) to their distal junction was assessed. After removal of the hamstring group, the shape, orientation, and dimension of the tendon footprints were determined. One cadaver demonstrated unique anatomy, which was considered as an anatomic variant and was therefore excluded from the study group. The ST and LB had a common origin on the posterolateral aspect of the ischial tuberosity (ST/LB), whereas the semimembranosus (SM) had a separated origin at the anterolateral aspect. The mean distance from the most proximal border of the ST/LB origin to the distal junction was 10.0 ± 1.3 cm. The shape of both footprints was longitudinal-oval, with the longitudinal axes of the SM and ST/LB footprints parallel aligned. Mean tendon width was 3.4 ± 0.5 cm for the common ST/LB complex and 4.2 ± 0.9 cm for the SM (p = 0.009). The corresponding values for tendon thickness were 1.0 ± 0.3 cm (ST/LB) and 0.8 ± 0.2 cm (SM), respectively (n.s.). Mean footprint length was 3.9 ± 0.4 cm for ST/LB and 4.5 ± 0.5 cm for SM (p = 0.002). The corresponding values for footprint height were 1.4 ± 0.5 cm (ST/LB) and 1.2 ± 0.3 cm (SM), respectively (n.s.). The ST and LB had a common origin, whereas the SM originated separately. The site of origin of both tendons was the lateral aspect of the ischial tuberosity, with the SM footprint lying directly anterior to the footprint of the ST/LB complex. The footprint of the SM was significantly wider than the footprint of

Does Seat Location Matter? A Review of the Proximity Effect in Large and Small Classrooms

ERIC Educational Resources Information Center

LaCroix, Kim; LaCroix, Sean

2017-01-01

The proximity effect--whether distance from an instructor correlates with grades--has been the topic of many articles dating back nearly 100 years. Despite this attention, a cleavage in the literature remains. Some authors argue that increased proximity to the instructor negatively relates with academic performance while others maintain no…

[Eugenics and Falange through the journal Ser (1942-1957)].

PubMed

Rendon, Sara Navarro

2016-01-01

Biopolitics has played an important role in fascist totalitarianism and the-Francoist regime was no exception. From the and with ultimate goal or regulating the population, measures were implemented to increase, care for and indoctrinate the population. This present study analyses the selection and promotion measures of some populations and the marginalisation of others proposed the Spanish Falangist Movement's official publication in the field of medicine, the journal Ser, Revista Medico-Social by the National Delegation of Health of the Traditionalist Spanish Phalanx of the Committees of the National Syndicalist Offensivie (F.E.T y de las J. O. N. S. 1942-1957). In this respect, the analysis of eugenic ideas and practice defended therein become especially interesting, claiming that, through indoctrination and health development, the race would be improved both physically and mentally. From the systematic analysis of the journals's contenets it has been demonstrated that this was one of the instruments used by the dictatorial regime to reconfigure eugenics in accordance with Catholic morals and national syndicalist politics.

Comparison of the proximal chevron and Ludloff osteotomies for the correction of hallux valgus.

PubMed

Choi, Woo Jin; Yoon, Han Kook; Yoon, Hang Seob; Kim, Bom Soo; Lee, Jin Woo

2009-12-01

Although several studies have described good results of proximal chevron and Ludloff osteotomies, there have been no studies comparing the results of these two techniques at a single institution. We consecutively evaluated 46 patients who underwent proximal chevron osteotomies and 52 patients who underwent Ludloff osteotomies. Patients were evaluated by preoperative and postoperative weight bearing radiographs and the American Orthopaedic Foot and Ankle Society (AOFAS) hallux MP score. Both groups had similarly high AOFAS scores and good correction by radiographic parameters. No statistically significant differences were found with respect to correction of hallux valgus angle (HVA) and intermetatarsal angle (IMA) between the two groups. Significant shortening of the first metatarsal was found after Ludloff osteotomy (p < 0.05). At 6 weeks after surgery, the pain subscore was significantly lower in the proximal chevron group than in the Ludloff group (p < 0.05). The proximal chevron and Ludloff osteotomies yielded equivalent clinical and radiological results. The Ludloff osteotomy with lag screw fixation is more stable and does not require postoperative hardware removal, although it is technically demanding and has a tendency toward greater shortening of the first metatarsal.

Proximity alert! Distance related cuneus activation in military veterans with anger and aggression problems.

PubMed

Heesink, Lieke; Edward Gladwin, Thomas; Terburg, David; van Honk, Jack; Kleber, Rolf; Geuze, Elbert

2017-08-30

Problems involving anger and aggression are common after military deployment, and may involve abnormal responses to threat. This study therefore investigated effects on neural activation related to threat and escapability among veterans with deployment experience. Twenty-seven male veterans with anger and aggression problems (Anger group) and 30 Control veterans performed a virtual predator-task during fMRI measurement. In this task, threat and proximity were manipulated. The distance of cues determined their possibility for escape. Cues signaled impending attack by zooming in towards the participant. If Threat cues, but not Safe cues, reached the participants without being halted by a button press, an aversive noise (105dB scream) was presented. In both the Threat and the Safe condition, closer proximity of the virtual predator resulted in stronger activation in the cuneus in the Anger versus Control group. The results suggest that anger and aggression problems are related to a generalized sensitivity to proximity rather than preparatory processes related to task-contingent aversive stimuli. Anger and aggression problems in natural, dynamically changing environments may be related to an overall heightened vigilance, which is non-adaptively driven by proximity. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Preoperative determination of appropriate cutting line for proximal gastrectomy to avoid postoperative jejunal ulcer.

PubMed

Takahashi, Naoto; Kashimura, Hirotaka; Nimura, Hiroshi; Watanabe, Atsushi; Yano, Kentaro; Aoki, Hiroaki; Koyama, Tomoki; Sasaki, Toshiyuki; Shida, Atsuo; Mitsumori, Norio; Aoki, Teruaki; Kashiwagi, Hideyuki; Yanaga, Katsuhiko

2012-01-01

Although proximal gastrectomy has become a procedure of choice for patients' early cancer in the upper third of stomach, no clinical guide for optimal gastric resection in order to avoid postoperative jejunal ulcer is available. The aim of this study was to investigate whether determining the distribution of parietal and chief cells of the stomach using Congo red test is clinically relevant. The F-line was defined as a boundary line between fundic and intermediate area of the stomach according to the pathological findings in 29 patients who underwent total gastrectomy for early gastric cancer, whereas the f-line was regarded as a boundary line between intermediate and pyloric area. In the additional 6 patients undergoing vagus-preserving proximal gastrectomy with jejunal pouch interposition, endoscopic Congo red test was preoperatively performed to determine the F-f-line. The distances from the pyloric ring to f-line on the lesser and greater curvatures were variable. Long-term outcomes of proximal gastrectomy guided by preoperative endoscopic Congo red test were favorable. It is suggested that preoperative endoscopic Congo red test is useful to determine the appropriate cutting line in order to avoid postoperative jejunal ulcer after proximal gastrectomy.

Allograft-prosthetic composite reverse total shoulder arthroplasty for reconstruction of proximal humerus tumor resections.

PubMed

King, Joseph J; Nystrom, Lukas M; Reimer, Nickolas B; Gibbs, C Parker; Scarborough, Mark T; Wright, Thomas W

2016-01-01

Proximal humerus reconstructions after resection of tumors are challenging. Early success of the reverse shoulder arthroplasty for reconstructions has recently been reported. The reverse allograft-prosthetic composite offers the advantage of improved glenohumeral stability compared with hemiarthroplasty for proximal humeral reconstructions as it uses the deltoid for stability. This article describes the technique for treating proximal humeral tumors, including preoperative planning, biopsy principles, resection pearls, soft tissue tensioning, and specifics about reconstruction using the reverse allograft-prosthetic composite. Two cases are presented along with the functional outcomes with use of this technique. Biomechanical considerations during reconstruction are reviewed, including techniques to improve the deltoid compression force. Reported instability rates are less with reverse shoulder arthroplasty reconstruction as opposed to hemiarthroplasty or total shoulder arthroplasty reconstructions of tumor resections. Reported functional outcomes are promising for the reverse allograft-prosthetic composite reconstructions, although complications are reported. Reverse allograft-prosthetic composites are a promising option for proximal humeral reconstructions, although nonunion of the allograft-host bone junction continues to be a challenge for this technique. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Vygotsky's Zone of Proximal Development: Implications for Gifted Education.

ERIC Educational Resources Information Center

Shaughnessy, Michael F.

This paper reviews Lev Vygotsky's theories concerning optimizing of potential through assistance, support, or instruction. The paper notes that there is a "zone of proximal development" or a band around intelligence quotient (IQ) scores reflecting one's true potential. IQ tests are generally well-standardized and "static,"…

Proximal Opening Wedge Osteotomy Provides Satisfactory Midterm Results With a Low Complication Rate.

PubMed

Oravakangas, Rami; Leppilahti, Juhana; Laine, Vesa; Niinimäki, Tuukka

2016-01-01

Hallux valgus is one of the most common foot deformities. Proximal opening wedge osteotomy is used for the treatment of moderate and severe hallux valgus with metatarsus primus varus. However, hypermobility of the first tarsometatarsal joint can compromise the results of the operation, and a paucity of midterm results are available regarding proximal open wedge osteotomy surgery. The aim of the present study was to assess the midterm results of proximal open wedge osteotomy in a consecutive series of patients with severe hallux valgus. Thirty-one consecutive adult patients (35 feet) with severe hallux valgus underwent proximal open wedge osteotomy. Twenty patients (35.5%) and 23 feet (34.3%) were available for the final follow-up examination. The mean follow-up duration was 5.8 (range 4.6 to 7.0) years. The radiologic measurements and American Orthopaedic Foot and Ankle Society hallux-metatarsophalangeal-interphalangeal scores were recorded pre- and postoperatively, and subjective questionnaires were completed and foot scan analyses performed at the end of the follow-up period. The mean hallux valgus angle decreased from 38° to 23°, and the mean intermetatarsal angle correction decreased from 17° to 10°. The mean improvement in the American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal score increased from 52 to 84. Two feet (5.7%) required repeat surgery because of recurrent hallux valgus. No nonunions were identified. Proximal open wedge osteotomy provided satisfactory midterm results in the treatment of severe hallux valgus, with a low complication rate. The potential instability of the first tarsometatarsal joint does not seem to jeopardize the midterm results of the operation. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Tubular Obstruction Leads to Progressive Proximal Tubular Injury and Atubular Glomeruli in Polycystic Kidney Disease

PubMed Central

Galarreta, Carolina I.; Grantham, Jared J.; Forbes, Michael S.; Maser, Robin L.; Wallace, Darren P.; Chevalier, Robert L.

2015-01-01

In polycystic kidney disease (PKD), renal parenchyma is destroyed by cysts, hypothesized to obstruct nephrons. A signature of unilateral ureteral obstruction, proximal tubular atrophy leads to formation of atubular glomeruli. To determine whether this process occurs in PKD, kidneys from pcy mice (moderately progressive PKD), kidneys from cpk mice (rapidly progressive PKD), and human autosomal dominant PKD were examined in early and late stages. Integrity of the glomerulotubular junction and proximal tubular mass were determined in sections stained with Lotus tetragonolobus lectin. Development of proximal tubular atrophy and atubular glomeruli was determined in serial sections of individual glomeruli. In pcy mice, most glomerulotubular junctions were normal at 20 weeks, but by 30 weeks, 56% were atrophic and 25% of glomeruli were atubular; glomerulotubular junction integrity decreased with increasing cyst area (r = 0.83, P < 0.05). In cpk mice, all glomerulotubular junctions were normal at 10 days, but by 19 days, 26% had become abnormal. In early-stage autosomal dominant PKD kidneys, 50% of glomeruli were atubular or attached to atrophic tubules; in advanced disease, 100% were abnormal. Thus, proximal tubular injury in cystic kidneys closely parallels that observed with ureteral obstruction. These findings support the hypothesis that, in renal cystic disorders, cyst-dependent obstruction of medullary and cortical tubules initiates a process culminating in widespread destruction of proximal convoluted tubules at the glomerulotubular junction. PMID:24815352

Many-body localization proximity effects in platforms of coupled spins and bosons

NASA Astrophysics Data System (ADS)

Marino, J.; Nandkishore, R. M.

2018-02-01

We discuss the onset of many-body localization in a one-dimensional system composed of a XXZ quantum spin chain and a Bose-Hubbard model linearly coupled together. We consider two complementary setups, depending whether spatial disorder is initially imprinted on spins or on bosons; in both cases, we explore the conditions for the disordered portion of the system to localize by proximity of the other clean half. Assuming that the dynamics of one of the two parts develops on shorter time scales than the other, we can adiabatically eliminate the fast degrees of freedom, and derive an effective Hamiltonian for the system's remainder using projection operator techniques. Performing a locator expansion on the strength of the many-body interaction term or on the hopping amplitude of the effective Hamiltonian thus derived, we present results on the stability of the many-body localized phases induced by proximity effect. We also briefly comment on the feasibility of the proposed model through modern quantum optics architectures, with the long-term perspective to realize experimentally, in composite open systems, Anderson or many-body localization proximity effects.

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.

Radiographic diagnosis of proximal caries-influence of experience and gender of the dental staff.

PubMed

Geibel, Margrit-Ann; Carstens, S; Braisch, U; Rahman, A; Herz, M; Jablonski-Momeni, A

2017-12-01

The aim of this study was to examine the influence of experience and gender on the radiographic detection of proximal caries lesions and on therapeutic decisions. A survey of 220 examiners (students and employees at three universities and dentists in the field) was taken using a standardized written questionnaire concerning radiographic diagnosis and therapy planning. An expert opinion of four dentists was determined as radiographic reference. A mixed effect logistic regression model was used for statistical evaluation and the odds ratio and p values were calculated (α = 0.05). Examiners with experience had an almost four times greater chance of a correct assessment, if proximal caries lesion was present or not, than examiners with low experience (OR 3.7 (95% CI 2.4-5.8)). No gender-specific differences were discovered (OR women vs. men 0.9 (95% CI 0.6-1.4)). There was a relationship between the severity of the burnout effect on the x-ray and false positive caries diagnosis. Overall, 43% of respondents would plan invasive treatment in the enamel on a patient at low risk of caries and 78% on a high-risk patient. The results showed that the more experienced practitioners would be more likely to postpone restorative therapy on proximal caries until the lesion reached a later stage. The results of this study suggest that examiner's experience influences the radiographic diagnosis of proximal lesions. No gender-specific differences could be found. Examiner's professional experience is an important factor when radiography is included for detection and treatment planning of proximal lesions.

In vivo antibody-mediated modulation of aminopeptidase A in mouse proximal tubular epithelial cells.

PubMed

Mentzel, S; Dijkman, H B; van Son, J P; Wetzels, J F; Assmann, K J

1999-07-01

Aminopeptidase A (APA) is one of the many renal hydrolases. In mouse kidney, APA is predominantly expressed on the brush borders and sparsely on the basolateral membranes of proximal tubular epithelial cells. However, when large amounts of monoclonal antibodies (MAbs) against APA were injected into mice, we observed strong binding of the MAbs to the basolateral membranes, whereas the MAbs bound only transiently to the brush borders of the proximal tubular epithelial cells. In parallel, APA itself disappeared from the brush borders by both endocytosis and shedding, whereas it was increasingly expressed on the basolateral sides. Using ultrastructural immunohistology, we found no evidence for transcellular transport of endocytosed APA to the basolateral side of the proximal tubular epithelial cells. The absence of transcellular transport was confirmed by experiments in which we used a low dose of the MAbs. Such a low dose did not result in binding of the MAbs to the brush borders and had no effect on the presence of APA in the brush borders of the proximal tubular epithelial cells. In these experiments we still could observe binding of the MAbs to the basolateral membranes in parallel with the local appearance of APA. In addition, treatment of mice with chlorpromazine, a calmodulin antagonist that interferes with cytoskeletal function, largely inhibited the MAb-induced modulation of APA. Our studies suggest that injection of MAbs to APA specifically interrupts the normal intracellular traffic of this enzyme in proximal tubular epithelial cells. This intracellular transport is dependent on the action of cytoskeletal proteins.

Construal level and free will beliefs shape perceptions of actors' proximal and distal intent

PubMed Central

Plaks, Jason E.; Robinson, Jeffrey S.

2015-01-01

Two components of lay observers' calculus of moral judgment are proximal intent (the actor's mind is focused on performing the action) and distal intent (the actor's mind is focused on the broader goal). What causes observers to prioritize one form of intent over the other? The authors observed whether construal level (Studies 1–2) and beliefs about free will (Studies 3–4) would influence participants' sensitivity to the actor's proximal vs. distal intent. In four studies, participants read scenarios in which the actor's proximal and distal intent were independently manipulated. In Study 1, when only distal intent was present in the actor's mind, participants rated the psychologically distant actor more responsible than the psychologically near actor. In Study 2, when only distal intent was in the actor's mind, participants with a chronic high level of action identification rated the actor more responsible than did those with a low level of action identification. In both studies, when only proximal intent was in the actor's mind, construal level did not predict judgments of responsibility. In Study 3, when only proximal intent was present in the actor's mind, the more participants believed in free will, the more they rated the actor responsible. When only distal intent was in the actor's mind, free will belief did not influence ratings of responsibility. In Study 4, the same pattern emerged when free will/determinism beliefs were manipulated and the actor performed a positive (life-saving) act. The authors discuss how these results shed new light on the literatures on moral reasoning and psycho-legal theory. PMID:26106352