cssi/SciSciGPT-SciSciNet huggingface dataset:
Stem cell-free therapy for glaucoma to preserve vision

Abstract Glaucoma is the leading cause of irreversible blindness with trabecular meshwork (TM) dysfunction resulting in elevated intraocular pressure and retinal ganglion cell (RGC) damage leading to vision loss. In this study, we discovered that secretome, derived from human TM stem cells, via minimal invasive periocular injection, can reduce intraocular pressure, restore TM homeostasis, protect RGC, and restore RGC function in both steroid-induced and genetic myocilin mutant mouse models of glaucoma. The secretome upregulated the COX2-PGE2 axis via mitochondrial TMEM177 and led to activation of endogenous stem cells and TM regeneration. Inhibition of COX2 abolished the protective effect of secretome on TM cells. Secretome treatment also enhanced RGC survival and function. Proteomic analysis revealed that the secretome is enriched with proteins involved in extracellular matrix modulation leading to the remodeling of TM to restore homeostasis. This study highlights the feasibility of stem cell-free therapy for glaucoma with minimal invasive administration and the involvement of multiple novel pathways for a cumulative regenerative effect on the TM to protect RGC. Brief summary This study describes a cell-free treatment using stem cell secretome in two animal models of glaucoma and explores the potential mechanisms
Data report : major and trace element data for leg 202 sites 1233 and 1234

The exchange of waters between the Pacific and the Southern Oceans occurs along the eastern boundary of the South Pacific. Because water masses of the Antarctic provide a connection among the world’s ocean basins, these water masses maintain the ability to influence changes in ocean circulation and climate (Lynch-Stieglitz et al., 1996). One of the primary goals of Ocean Drilling Program (ODP) Leg 202 was to exploit the sediments underlying the southeast Pacific continental margin to ascertain how changes in past ocean circulation (i.e., water mass distributions) have affected global carbon, heat, and nutrient balances. In the southeast Pacific, oxygen-rich Antarctic Intermediate Water (AAIW) combines with (low oxygen) North Pacific Intermediate Water to produce a steep water column–dissolved oxygen gradient between depths of ~0.5 and 1 km. Shallower in the water column, the classical oxygen minimum zone (OMZ) impinges along the continental margin. These different water masses thus produce a “double” OMZ, with lowoxygen waters straddling the oxygen-rich AAIW. Given this distribution, changes in the intensity of water mass source functions through time should leave behind a depth transect of changing proxy distributions in response to changing bottom water oxygen concentrations. Sediments at Site 1233 are bathed by AAIW at a water depth of 838 m, whereas Pacific Central Water bathes the overlying waters at Site 1234. Site 1234 is located north of Site 1233 at 1015-m water depth. Because of rapid erosion of the high Andes, terrigenous sedimentation rates at these sites are in the range of 1–2 m/k.y. 1McManus, J., 2006. Data report: major and trace element data for Leg 202 Sites 1233 and 1234. In Tiedemann, R., Mix, A.C., Richter, C., and Ruddiman, W.F. (Eds.), Proc. ODP, Sci. Results, 202: College Station, TX (Ocean Drilling Program), 1–9. doi:10.2973/odp.proc.sr.202.202.2006 2College of Oceanic and Atmospheric Sciences, Oregon State University, 104 Ocean Administration Building, Corvallis OR 97331-5503, USA. mcmanus@coas.oregonstate.edu
ADVERSE DRUG INTERACTIONS IN DENTAL PRACTICE: INTERACTIONS ASSOCIATED WITH LOCAL ANESTHETICS, SEDATIVES AND ANXIOLYTICS: PART IV OF A SERIES

ABSTRACT Background This article is the fourth in a five-part series based on a 1998 International Association for Dental Research symposium entitled “Adverse Drug Interactions in Dentistry: Separating the Myths From the Facts.” The symposium evaluated the significance of various drug interactions associated with dental therapeutics. Methods Local anesthesia and preoperative oral sedative/anxiolytic therapy often are indicated for routine oral surgery and restorative dentistry. The author conducted a literature review of the drug interactions associated with the use of local anesthetics and sedatives. The quality of the information used to document these interactions and the severity of the possible adverse outcome were assessed using a significance rating scale for dental drug interactions. Results Many of the frequently described drug interactions were found to be poorly documented in the dental and medical literature. Others were determined not to be relevant to current dental practice. The use of local anesthetics, sedatives or anxiolytic agents in combination with other central nervous system depressant agents or in combination with drugs that inhibit their metabolism was associated with a few serious adverse drug interactions or complications. Conclusions The adverse drug interactions associated with the use of local anesthetics and oral sedative/anxiolytic agents in general practice vary in significance. An understanding of possible adverse drug interactions in dentistry may help practitioners avoid and prevent these complications.
Progress in the Development of Tier 2 Light-Duty Diesel Vehicles

The U.S. Environmental Protection Agency (U.S. EPA) has been conducting a test program to evaluate efforts to bring light-duty diesel vehicles into compliance with U.S. Federal Tier 2 Light-duty Emission Standards. Between April 2002 and October 2003, five advanced prototype light-duty diesel vehicles equipped with NOx adsorption catalysts, PM-traps, and diesel oxidation catalysts were tested at the U.S. EPA’s National Vehicle and Fuel Emission Laboratory (NVFEL). The vehicle testing was conducted using low sulfur (<15 ppm) diesel fuel. All of the tested vehicles demonstrated the considerable progress recently made by vehicle manufacturers and systems integrators in applying advanced NOx and PM emission control technology to light duty diesel vehicles in anticipation of the U.S. Lightduty Tier 2 emission standards. PM emissions for all of the vehicles were well below the Tier 2 Bin-5 emission levels. The most recently tested vehicle demonstrated intermediate-useful life (50,000 miles) PM, NOx, and NMHC emissions at or below the Tier 2 Bin-5 levels. This paper represents an early survey of emissions from the first generation of prototype clean diesel vehicles.
Thigh adipose tissue distribution is associated with insulin resistance in obesity and in type 2 diabetes mellitus.

BACKGROUND Adipose tissue (AT) content of the thigh is generally not considered to be associated with insulin resistance (IR), but it is unclear whether the distribution of AT in the thigh is a determinant of IR. OBJECTIVE We investigated whether subcompartments of AT within the thigh are determinants of IR. DESIGN Midthigh AT, muscle composition, and insulin sensitivity were compared in 11 obese patients with type 2 diabetes mellitus (DM); 40 obese, glucose-tolerant (GT) and 15 lean, GT volunteers; and 38 obese subjects who completed a weight-loss program. Midthigh AT area measured with computed tomography was partitioned into 3 components: subcutaneous AT (SCAT), AT beneath the fascia (SFAT), and AT infiltrating muscle groups (IMAT). Muscle attenuation characteristics were determined. RESULTS Obese DM and obese GT subjects had lower insulin sensitivity than lean GT subjects. SCAT was greater in obesity, yet did not correlate with insulin sensitivity. SFAT was approximately 8% of total thigh AT and correlated with insulin sensitivity. IMAT was highest in obese DM, and although it accounted for only approximately 3% of thigh AT, it was a strong correlate of insulin sensitivity. Mean attenuation was highest in lean subjects and was associated with higher insulin sensitivity. Weight loss reduced the amount of thigh AT, the proportion of thigh IMAT, and the amount of low-density thigh muscle. CONCLUSIONS SFAT and IMAT are markers of IR in obesity and DM although they are much smaller than SCAT, which does not predict IR. Muscle composition reflecting increased fat content is also associated with IR.
Antithrombotic strategy variability in ATrial fibrillation and obstructive coronary disease revascularized with PCI—rationale and study design of the prospective observational multicenter AVIATOR 2 registry

Background In the era of novel antithrombotic therapy, the optimal treatment for patients with nonvalvular atrial fibrillation (AF) or flutter undergoing percutaneous coronary intervention (PCI) is undetermined. Study design The AVIATOR 2 study is a multicenter prospective observational registry that will enroll approximately 2,500 patients with nonvalvular AF or flutter undergoing PCI starting March 2015 over an 18-month enrollment period. Antithrombotic therapy selection will be at the discretion of the treating physician. An integral feature of this study is the use of a smartphone-based survey to capture physician and patient perspectives regarding antithrombotic therapies after PCI. Survey-derived patient treatment concerns, perceived need, and affordability will be used to calculate the risk of non-adherence. Subjective risk for ischemic or bleeding events will be correlated with previously validated risk scores as well as observed event rates at 1, 6, or 12 months post-PCI. Endpoints The primary efficacy end point will be major adverse cardiac and cerebrovascular events, a composite occurrence of death, nonfatal myocardial infarction, stroke, stent thrombosis, and clinically driven target lesion revascularization at 1 year. The primary safety end point will be major bleeding as per Bleeding Academic Research Consortium criteria types 2, 3, or 5. The secondary end points will include (i) net adverse clinical events, a composite occurrence of all major adverse cardiac and cerebrovascular events, and major bleeding at 1 year; (ii) correlation between estimated subjective and objective (CHADS 2 , CHA 2 DS 2 -VASc, stent thrombosis score, HAS-BLED, and ATRIA scores) ischemic and bleeding risks; (iii) modes of antithrombotic therapy cessation and their impact on outcomes; and (iv) correlation between observed and expected non-adherence to treatment. Summary AVIATOR 2 is a real-world registry designed to evaluate ischemic and bleeding outcomes according to conventional and novel antithrombotic regimens in patients with nonvalvular AF or flutter undergoing PCI. The study will also provide insights in to physician- and patient-centered factors affecting treatment selection and adherence and their overall impact on clinical outcomes. The study is registered on clinicaltrials.gov NCT02362659.
Immune Selection of Hot-Spot β2-Microglobulin Gene Mutations, HLA-A2 Allospecificity Loss, and Antigen-Processing Machinery Component Down-Regulation in Melanoma Cells Derived from Recurrent Metastases following Immunotherapy

Scanty information is available about the mechanisms underlying HLA class I Ag abnormalities in malignant cells exposed to strong T cell-mediated selective pressure. In this study, we have characterized the molecular defects underlying HLA class I Ag loss in five melanoma cell lines derived from recurrent metastases following initial clinical responses to T cell-based immunotherapy. Point mutations in the translation initiation codon (ATG-->ATA) and in codon 31 (TCA-->TGA) of the beta(2)-microglobulin (beta(2)m) gene were identified in the melanoma cell lines 1074MEL and 1174MEL, respectively. A hot-spot CT dinucleotide deletion within codon 13-15 was found in the melanoma cell lines 1106MEL, 1180MEL, and 1259MEL. Reconstitution of beta(2)m expression restored HLA class I Ag expression in the five melanoma cell lines; however, the HLA-A and HLA-B,-C gene products were differentially expressed by 1074MEL, 1106MEL, and 1259MEL cells. In addition, in 1259MEL cells, the Ag-processing machinery components calnexin, calreticulin, and low m.w. polypeptide 10 are down-regulated, and HLA-A2 Ags are selectively lost because of a single cytosine deletion in the HLA-A2 gene exon 4. Our results in conjunction with those in the literature suggest the emergence of a preferential beta(2)m gene mutation in melanoma cells following strong T cell-mediated immune selection. Furthermore, the presence of multiple HLA class I Ag defects within a tumor cell population may reflect the accumulation of multiple escape mechanisms developed by melanoma cells to avoid distinct sequential T cell-mediated selective events.
Effect of guard band and guard time on mean message transmission delays in FDMA and TDMA (satellite communications)

The effects of guard bands in frequency division multiple access (FDMA) and guard times in time division multiple access (TDMA) on message transmission delays are analyzed. The difference in the mean transmission delays in FDMA and in TDMA is obtained, considering the overhead due to guard bands and guard times. An analytical model and assumptions are presented. >
Variability of particulate organic carbon concentration in the north polar Atlantic based on ocean color observations with Sea-viewing Wide Field-of-view Sensor (SeaWiFS)

We use satellite data from Sea-viewing Wide Field-of-view Sensor (SeaWiFS) to investigate distributions of particulate organic carbon (POC) concentration in surface waters of the north polar Atlantic Ocean during the spring summer season (April through August) over a 6-year period from 1998 through 2003. By use of field data collected at sea, we developed regional relationships for the purpose of estimating POC from remote-sensing observations of ocean color. Analysis of several approaches used in the POC algorithm development and match-up analysis of coincident in situ derived and satellite-derived estimates of POC resulted in selection of an algorithm that is based on the blue-to-green ratio of remote-sensing reflectance R(sub rs) (or normalized water-leaving radiance L(sub wn)). The application of the selected algorithm to a 6-year record of SeaWiFS monthly composite data of L(sub wn) revealed patterns of seasonal and interannual variability of POC in the study region. For example, the results show a clear increase of POC throughout the season. The lowest values, generally less than 200 mg per cubic meters, and at some locations often less than 50 mg per cubic meters, were observed in April. In May and June, POC can exceed 300 or even 400 mg per cubic meters in some parts of the study region. Patterns of interannual variability are intricate, as they depend on the geographic location within the study region and particular time of year (month) considered. By comparing the results averaged over the entire study region and the entire season (April through August) for each year separately, we found that the lowest POC occurred in 2001 and the highest POC occurred in 2002 and 1999.
EFFECT OF HYPOPHYSIAL STALK SECTION ON ADENOHYPOPHYSIAL FUNCTION

ALTHOUGH neural regulation of neurohypophysial secretion is generally accepted, the mechanism of adenohypophysial secretion is undetermined. Direct neural control of thyrotrophic (Uotila, 1939; Brolin, 1946) and gonadotrophic secretion (Brooks, 1940) has been postulated, but more recent studies postulate that neurohumors regulate secretion of some adenohypophysial hormones (Markee, Sawyer and Hollins-head, 1946; Harris, 1948; Hume and Wittenstein, 1950). For adrenocorticotrophic hormone (ACTH) secretion, there is special a priori reason to suspect neural regulation. Secretion of this hormone is accelerated by a wide variety of “stress conditions” (heat, cold, anoxia, pain, toxins, etc.). These stimuli, apparently unrelated, share the common property of exciting sympathetic nervous discharge and liberating epinephrine. For this reason, epinephrine has been proposed as the excitatory link between stress exposure and ACTH secretion (Vogt, 1944; Long, 1947). Direct neural control of the adenohypophysis via th...
Effect of cadmium chloride on transepithelial electrical resistance of Sertoli cell monolayers in two-compartment cultures--a new model for toxicological investigations of the "blood-testis" barrier in vitro.

The effect of various doses (0.75–24 μm) of cadmium chloride (CdCl2) on the development of intercellular tight junctions by immature rat Sertoli cells (Sc) was investigated in vitro using the two-compartment culture system. The status of tight junctions was monitored by repeated measurements of the transepithelial electrical resistance (TER). For defining the specificity of CdCl2 effects, the TER changes were correlated with Sc secretory activity (immunoactive inhibin), the cell number (DNA content), and viability (MTT test). The effects of CdCl2 depended on the concentration of the toxicant as well as on the onset and duration of exposure (4 and 18 hr on Day 1 or 5 of culture). The observed effects could be divided into four categories: (1) At highest doses employed, the TER values decreased significantly and irreversibly during 13 days of culture, and the decrease was accompanied by a significant and irreversible drop in inhibin secretion, cell viability, and cell number. (2) Within a narrow range of doses, the irreversible, or only partially reversible, decrease of TER was accompanied by a transient decrease, or no change, of the secretory activity and no significant changes in Sc cell number and/or viability. (3) With still lower doses, the TER values rapidly decreased and then returned to control level within 3–4 days. In this group, no changes in either inhibin secretion or cell viability were observed. (4) Exposure to the lowest doses of CdCl2 caused a delayed, but significant increase in TER. This increase was not accompanied by noticeable changes in other parameters evaluated. These data suggest that CdCl2 may selectively compromise, at least in vitro, the development and maintenance of the inter-Sc tight junctions, without affecting the secretory activity or the cell number and viability. However, increasing cumulative doses of CdCl2 (concentration multiplied by the time of exposure) led to decreased inhibin secretion and cell viability and then, finally, to irreversible cell damage and death. We believe that the experimental model and approach reported in this paper should be very useful for investigating the mechanism of action of known or potential testicular toxicants, particularly those suspected to compromise the integrity of the “blood-testis” barrier.
Immunocytochemical evidence for antibody binding to mast cell granules

Abstract Immunocytochemical studies of lymphoid tissues of the rat indicate that immunoglobulins possess strong affinity for some component of mast cell granules. In appropriately fixed tissue, binding of antibody to mast cell granules was stronger and more consistent than binding to any other tissue component examined. Both heterologous and homologous antibody bound to mast cell granules. Several crude antiserum preparations as well as purified IgG fraction exhibited binding. Antibody was capable of binding to mast cell granules in thin sections of Epon-embedded material.
Visceral cortex: A direct connection from prefrontal cortex to the solitary nucleus in rat

Abstract Injections of the fluorescent retrograde axonal tracer, True Blue, into the solitary complex (a visceral and taste center in the medulla) labeled pyramidal cell bodies deep in the medial, prefrontal cortex and especially lateral prefrontal (or insular) cortex of the rat. Injections of the anterograde axonal tracer (wheat germ agglutinin conjugated to horseradish peroxidase) into the prefrontal cortex produced bilateral labeling throughout much of the solitary nucleus. The distribution of prefrontal cortical cells projecting directly to the solitary nucleus may provide one clear anatomical criterion for identifying regions of cerebral cortex that may influence visceral function.
Methods of reducing energy consumption of the oxidant supply system for MHD/steam power plants

An in-depth study was conducted to identify possible improvements to the oxidant supply system for combined cycle MHD power plants which would lead to higher thermal efficiency and reduction in the cost of electricity, COE. Results showed that the oxidant system energy consumption could be minimized when the process was designed to deliver a product O2 concentration of 70 mole percent. The study also led to the development of a new air separation process, referred to as 'liquid pumping and internal compression'. MHD system performance calculations show that the new process would permit an increase in plant thermal efficiency of 0.6 percent while allowing more favorable tradeoffs between magnetic energy and oxidant system capacity requirements.
A micro quantitative determination of total fatty acids in biological samples by esterification with radioactive methanol

Abstract By the application of the isotope derivative technique with radioactive methanol, a procedure for measuring esterified and nonesterified fatty acids was devised. The present method is ideally suited to measuring large numbers of biological samples when total fatty acid content is required. The wide range of sample size, short time required for measurement, applicability to both free and esterified fatty acids, and possibility of computorized data processing make the present method a valuable supplement to gasliquid chromatography.
Preliminary results from intensity-based CT-SPECT fusion in I-131 anti-B1 monoclonal-antibody therapy of lymphoma

BACKGROUND In treatment of non-Hodgkin's lymphoma patients with predose-plus-I-131-labeled anti-B1 (anti-CD20) monoclonal antibody, an intratherapy single photon emission computed tomography (SPECT) image is an important part of research estimates of tumor dosimetry. For that imaging, a computed tomography (CT)-SPECT fusion is used both to obtain an attenuation map for the space-alternating generalized expectation maximization reconstruction and to provide CT-based volumes of interest (VoI) to determine activity in tumors and organs. Fusion based on external, skin-surface markers has been used but may not correctly superimpose internal structures. METHODS A new algorithm, developed and implemented in the Department of Radiology, University of Michigan, and based on the mutual information of gray-scale values, was investigated. Results from four anti-B1 therapy patients are presented. RESULTS In one patient, the new intensity-based fusion provided total reconstructed counts for kidneys that were higher than those produced by marker-based fusion; therefore, the VoI was probably located more accurately. In a second patient, after an acquisition that did not include any skin markers, the new algorithm produced counts/pixel that were similar for four of five tumors consistent with what is expected from an ideal therapy combined with accurate count density estimates. The fifth tumor was quite small and will have its final activity estimate moved toward consistency with the others after a recovery coefficient multiplication. For four tumors in two patients, direct comparison of the two algorithms yielded count totals that were different by no more than 7.2%. CONCLUSIONS The use of CT-SPECT fusion and subsequent transfer of tumor VoI originally drawn in high-resolution CT space offers potential advantages for quantifying tumor uptake of radioactivity. A new, mutual-information-based fusion algorithm is usable without skin markers. Results indicate that the new fusion algorithm gives equal tumor count values within 7.2% compared with fusion based on external markers. It increases estimates of kidney activity by an average of 6.4%. Cancer 1997; 80:2538-44. © 1997 American Cancer Society.
Mammalian Dicer finds a partner

RNA interference (RNAi) is a complex process that uses small RNAs of 21–23 nucleotides to guide sequence‐specific silencing of genetic information at both the transcriptional and post‐transcriptional levels. There are two main post‐transcriptional gene‐silencing pathways in metazoans: the microRNA (miRNA)‐mediated inhibition of translation and the small interfering RNA (siRNA)‐mediated targeted degradation of RNAs (reviewed in Hannon & Rossi, 2004; He & Hannon, 2004; Filipowicz et al , 2005; Tomari & Zamore, 2005). miRNAs are generally characterized by imperfect helices both in the precursor (pre‐miRNA) and in the binding of the miRNA antisense strand to the target, which usually takes place within the 3′ untranslated region of the mRNA. siRNAs generally have near‐perfect Watson–Crick base pairs (bp), both in the double‐stranded precursors and in the pairing of the antisense strand with the target mRNA, which can occur throughout the message. RNAi is active in organisms ranging from the fission yeast Schizosaccharomyces pombe through to humans. An important aspect of RNAi is the strong evolutionary conservation of many of the components involved. The most highly conserved proteins include members of the Argonaute family and the RNase III family of double‐stranded ribonucleases (Filipowicz et al , 2005; Tomari & Zamore, 2005) that cleave the precursors of miRNAs and siRNAs into 21–23 bp duplexes with two‐base 3′ overhangs. Despite the strong conservation of these proteins between kingdoms, there are important differences that relate to their specialized functional activities. For instance, in Drosophila , there are two distinct RNase III family members called Dicer. Dcr1 specializes in processing endogenous hairpin RNA precursors into miRNAs, whereas Dcr2 specializes in cleavage of double‐stranded RNAs (dsRNAs) that are destined to function as siRNAs (Tomari & Zamore, 2005). In plants, there are multiple forms of the Dicer protein that are specialized in either nuclear or cytoplasmic processing …
COLORECTAL CANCER AND PERITONEAL CARCINOMATOSIS

Colorectal cancer ranks third in new cancer cases and in cancer deaths in men and women combined in the United States. Additionally, the probability of developing an invasive colorectal cancer over one's lifetime is around 1 in 16. This amounts to approximately 133,000 new cancer cases and 55,000 cancer deaths yearly. Despite advances in adjuvant therapy for colorectal cancer, the peritoneal surface still remains a considerably high failure site for patients with recurrence of disease. Because of the favorable results of treating peritoneal metastases from ovarian cancer and pseudomyxoma peritonei with cytoreduction and intraperitoneal chemotherapy, this form of therapy has been investigated by several investigators in the management of patients with peritoneal metastases secondary to colorectal cancer. Preliminary studies seem to favor those patients with low-volume, low-grade peritoneal metastases, those with perforated cancers, and those patients in whom definitive cytoreduction is complete. Intraperitoneal chemotherapy with or without hyperthermia is a safe and logical way to administer dose-intensive therapy to the peritoneal cavity. © 1996 Wiley-Liss, Inc.
An Outer Membrane Protein Undergoes Enthalpy- and Entropy-Driven Transitions

β-Barrel membrane proteins often fluctuate among various open substates, yet the nature of these transitions is not fully understood. Using temperature-dependent, single-molecule electrophysiology analysis, along with rational protein design, we show that OccK1, a member of the outer membrane carboxylate channel from Pseudomonas aeruginosa, features a discrete gating dynamics comprising both enthalpy-driven and entropy-driven current transitions. OccK1 was chosen for the analysis of these transitions, because it is a monomeric transmembrane β-barrel of a known high-resolution crystal structure and displays three distinguishable, time-resolvable open substates. Native and loop-deletion OccK1 proteins showed substantial changes in the activation enthalpies and entropies of the channel transitions, but modest alterations in the equilibrium free energies, confirming that the system never departs from equilibrium. Moreover, some current fluctuations of OccK1 indicated a counterintuitive, negative activation enthalpy, which was compensated by a significant decrease in the activation entropy. Temperature scanning of the single-channel properties of OccK1 exhibited a thermally induced switch of the energetically most favorable open substate at the lowest examined temperature of 4 °C. Therefore, such a semiquantitative assessment of the current fluctuation dynamics not only demonstrates the complexity of channel gating but also reveals distinct functional traits of a β-barrel outer membrane protein under different temperature circumstances.
Oxygen mass transport limitations at the cathode of polymer electrolyte membrane fuel cells

Oxygen transport across the cathode gas diffusion layer (GDL) in polymer electrolyte membrane (PEM) fuel cells was examined by varying the O2/N2 ratio and by varying the area of the GDL extending laterally from the gas flow channel under the bipolar plate (under the land). As the cathode is depleted of oxygen, the current density becomes limited by oxygen transport across the GDL. Oxygen depletion from O2/N2 mixtures limits catalyst utilization, especially under the land.The local current density with air fed PEM fuel cells falls to practically zero at lateral distances under the land more than 3 times the GDL thickness; on the other hand, catalyst utilization was not limited when the fuel cell cathode was fed with 100% oxygen. The ratio of GDL thickness to the extent of the land is thus critical to the effective utilization of the catalyst in an air fed PEM fuel cell. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Effects of Estrogen Treatment on Arterial Wall Structure and Function

Premenopausal women are relatively protected against coronary heart disease (CHD) compared with men, but lose this advantage after surgical or natural menopause. Consequently, estrogens are believed to confer significant protection against coronary artery atherosclerosis (CAA). In addition, epidemiological studies have shown lower rates of CHD in postmenopausal users of estrogen replacement therapy than in women not taking hormone therapy. The cynomolgus monkey model (Macaca fascicularis) has proved valuable for gaining a better understanding of the effects of estrogen on coronary artery function and CAA. We have found that premenopausal cynomolgus monkeys have less CAA than male monkeys and surgically postmenopausal female monkeys, and that the hyperestrogenic state of pregnancy further inhibits CAA progression. Ovarian-deficient stressed females had more extensive CAA and impaired vascular function compared with unstressed monkeys, and estrogen-treated females (premenopausal or postmenopausal) had less CAA than untreated monkeys. The treatment effect in this model appears to be partially mediated by a decrease in low density lipoprotein uptake and/or degradation, and an improvement in coronary artery vascular function.
An empirical investigation of the visual rightness theory of picture perception.

This research subjected the visual rightness theory of picture perception to experimental scrutiny. It investigated the ability of adults untrained in the visual arts to discriminate between reproductions of original abstract and representational paintings by renowned artists from two experimentally manipulated less well-organized versions of each art stimulus. Perturbed stimuli contained either minor or major disruptions in the originals' principal structural networks. It was found that participants were significantly more successful in discriminating between originals and their highly altered, but not slightly altered, perturbation than expected by chance. Accuracy of detection was found to be a function of style of painting and a viewer's way of thinking about a work as determined from their verbal reactions to it. Specifically, hit rates for originals were highest for abstract works when participants focused on their compositional style and form and highest for representational works when their content and realism were the focus of attention. Findings support the view that visually right (i.e., "good") compositions have efficient structural organizations that are visually salient to viewers who lack formal training in the visual arts.
Independence of events and of random variables

The phenomenon of independence of random variables is shown to be singular in that, e.g., there are both finite and infinite sample spaces on which two random variables can be independent iff one is constant. Furthermore on [0,1], with Lebesgue measure for probability, the usual function spaces contain dense subsets each member of which is independent only of constants. Finally, the requirement of independence among a set of orthonormal functions is shown to imply, in all but trivial instances, that the orthogonal complement of the space is infinite-dimensional.
A Validation Procedure for a LADAR System Radiometric Simulation Model

The USU LadarSIM software package is a ladar system engineering tool that has recently been enhanced to include the modeling of the radiometry of Ladar beam footprints. This paper will discuss our validation of the radiometric model and present a practical approach to future validation work. In order to validate complicated and interrelated factors affecting radiometry, a systematic approach had to be developed. Data for known parameters were first gathered then unknown parameters of the system were determined from simulation test scenarios. This was done in a way to isolate as many unknown variables as possible, then build on the previously obtained results. First, the appropriate voltage threshold levels of the discrimination electronics were set by analyzing the number of false alarms seen in actual data sets. With this threshold set, the system noise was then adjusted to achieve the appropriate number of dropouts. Once a suitable noise level was found, the range errors of the simulated and actual data sets were compared and studied. Predicted errors in range measurements were analyzed using two methods: first by examining the range error of a surface with known reflectivity and second by examining the range errors for specific detectors with known responsivities. This provided insight into the discrimination method and receiver electronics used in the actual system.
Fairness and efficiency in web server protocols

We consider the problem of designing a preemptive protocol that is both fair and efficient when one is only concerned with the sojourn time of the job and not intermediate results. Our Fair Sojourn Protocol (FSP) is both efficient, in a strong sense (similar to the shortest remaining processing time protocol: SRPT), and fair, in the sense of guaranteeing that it weakly outperforms processor sharing (PS) for every job on any sample path.Our primary motivation is web serving in which the standard protocol is PS, while recent work proposes using SRPT or variants. Our work suggests both a framework in which to evaluate proposed protocols and an attractive new protocol, FSP.
The Successful Implementation of Application Software in New Production Systems

We conducted an empirical study in 18 manufacturing companies, interviewing 24 managers. Our findings suggest that to improve the successful implementation of manufacturing software, managers 1 should encourage direct interchange between software producers in-house programmers or vendors and the users production personnel; 2 should support the ultimate users production units before, during, and after the implementation of manufacturing software rather than concentrate on measuring the productivity of software producers; 3 should concentrate on software implementation carefully and set clear and feasible policies on acquisition and utilization of application software.
Aluminum hydroxide adjuvant produced under constant reactant concentration

Abstract Aluminum hydroxide adjuvant, AlO(OH), is used to potentiate the immune response to vaccines by adsorbing the antigen. The structure of aluminum hydroxide adjuvant is unusual as it is crystalline but has a high surface area due to its very small primary particles. The purpose of this study was to investigate the chemical and thermal conditions required to synthesize aluminum hydroxide adjuvant that is stable and exhibits a high protein adsorptive capacity. Aluminum hydroxide adjuvant was precipitated using a procedure in which the concentration of reactants was maintained constant throughout the precipitation. The precipitation variables were: 2.50, 2.75, and 3.00 OH/Al molar ratio; 0.5, 4.0, and 5.0 M NaCl; and 25, 60, and 65°C. High sodium chloride concentration and high temperature facilitated the formation of AlO(OH) rather than crystalline forms of aluminum hydroxide, Al(OH) 3 . The AlO(OH) produced was not stable because crystalline forms of aluminum hydroxide formed during aging at room temperature. Aluminum hydroxide adjuvant was stabilized for the study period of 12 weeks at room temperature by either the addition of 3.0 M NaCl after precipitation and washing or hydrothermal treatment at 110°C for 4 h. Stabilization by the addition of sodium chloride required a hypertonic concentration of sodium chloride and was not practical as vaccines for parenteral administration are desired to be isotonic (equivalent to 0.15 M NaCl). Stabilization by hydrothermal treatment produced aluminum hydroxide adjuvant, which exhibited a high protein adsorptive capacity that did not change during the 12-week study period.
Stability of N-terminal pro-brain natriuretic peptide after storage frozen for one year and after multiple freeze-thaw cycles.

Cardiac natriuretic peptides are of interest for their potential role in assisting in the diagnosis, prognosis, and monitoring of left ventricular dysfunction and congestive heart failure (1). An electrochemiluminescence immunoassay for the measurement of N-terminal pro-brain natriuretic peptide (NT-proBNP) on the Elecsys® immunoassay analyzer platform (Roche Diagnostics Corporation) has recently received Food and Drug Administration clearance to aid in the diagnosis of congestive heart failure (2). We report here on the stability of the NT-proBNP analyte when measured with the Roche Diagnostic NT-proBNP assay after specimen storage at −80 °C for longer than 1 year and after five freeze-thaw (−80 and 22 °C) cycles. Twenty-five samples were collected from healthy and heart failure clinic adult volunteers under informed consent according to the policies of the Washington University School of Medicine’s Institutional Review Board. All glass collection tubes were from Becton Dickinson. Lithium-heparin plasma (prod. no. 367686) was collected from …
Monolithic optical switching technology for a programmable optical logic gate array

Abstract Monolithic optical switches based on the integration of GaAs/AlGaAs vertical-cavity surface-emitting lasers with heterojunction phototransistors and photothyristors have evolved from a family of simple switches and logic capabilities to more complex switch nodes with increased functionality that are capable of performing optical logic and routeing in a dynamically programmable manner. The operation of these switches in different routeing and logic configurations is experimentally demonstrated. This technology provides the basis for compact, programmable optical logic processing and interconnection architectures, including a dynamically reconfigurable optical logic gate array that can be programmed using stored instruction sets (control voltages) to perform different combinational optical logic functions.
The sunk cost effect with pigeons: some determinants of decisions about persistence.

The sunk cost effect occurs when an individual persists following an initial investment, even when persisting is costly in the long run. The current study used a laboratory model of the sunk cost effect. Two response alternatives were available: Pigeons could persist by responding on a schedule key with mixed ratio requirements, or escape by responding on a second key. In Experiment 1, mean response requirements for persistence and escape were varied across conditions. Pigeons persisted (committing the sunk cost error) when persisting increased the mean response requirement only slightly but not when persisting was sufficiently nonoptimal. Experiment 2 explored more systematically combinations of ratios and probabilities assigned to the schedule key. Persistence varied with the ratio of the mean global response requirements for persistence and escape. In Experiment 3, transitions between ratios were signaled. This reduced nonoptimal persistence, and produced some instances of a reverse sunk cost error—escaping when persistence was optimal. In Experiment 4, it was optimal to escape after the second-smallest ratio ever presented. Pigeons escaped at approximately the optimal juncture, especially in conditions with added signals. Overall, this series of experiments suggests that the sunk cost error may arise in part because persistence is the default behavioral strategy in situations where the contingencies for escape and persistence are insufficiently disparate and/or it is relatively difficult to discriminate when to escape. The study also demonstrates the utility of animal models of complex decision making situations.
Window-Masked Segmented Digital Clock Manager-FPGA-Based Digital Pulsewidth Modulator Technique

This paper presents a new digital pulsewidth modulator (DPWM) architecture for field programmable gate array (FPGA)-based systems. The design of the proposed DPWM architecture is based on fully utilizing the digital clock manager (DCM) resources available on new FPGA boards. Furthermore, this architecture will also window-mask the DCM operation to only a portion of the switching period in order to decrease power dissipation. This proposed digital modulator technique allows for higher DPWM resolution with lower power consumption, the primary barrier to high switching frequency operation. The presented technique relies on power-optimized resources already existing on new FPGAs, and benefits from the inherit phase-shifting properties of the DCM blocks, which help in simplifying the duty cycle generation. The architecture can be applied to achieve different numbers of bits for the DPWM resolution designed for different dc-dc applications. The suggested architecture is first simulated, implemented, and experimentally verified on a Virtex-4 FPGA board.
Acyclic digraphs and local hierarchy theory

The degree of a vertex of a digraph is the number of outgoing edges minus the number of incoming edges. Acyclic digraphs give a model for networks such as citation networks and organizational charts. Motivated by a ''local hierarchy theory'' developed for this model, we consider the set [email protected]^(@d) of acyclic digraphs with a specified degree sequence @d. We show that all digraphs in this set can be generated from any one such digraph using just one kind of basic transformation. In the case of degree sequences @d that are minimal in the ''Lorenz order'', we investigate the maximum number of edges in an acyclic digraph in [email protected]^(@d) and show how to construct digraphs in [email protected]^(@d) with many edges. Determining this maximum number of edges seems to be a very difficult problem.
A field study of the accuracy and reliability of a biometric iris recognition system

Abstract Purpose The iris of the eye appears to satisfy the criteria for a good anatomical characteristic for use in a biometric system. The purpose of this study was to evaluate a biometric iris recognition system: Mobile-Eyes™. Methods The enrollment, verification, and identification applications were evaluated in a field study for accuracy and reliability using both irises of 277 subjects. Independent variables included a wide range of subject demographics, ambient light, and ambient temperature. A sub-set of 35 subjects had alcohol-induced nystagmus. There were 2710 identification and verification attempts, which resulted in 1,501,340 and 5540 iris comparisons respectively. Results In this study, the system successfully enrolled all subjects on the first attempt. All 277 subjects were successfully verified and identified on the first day of enrollment. None of the current or prior eye conditions prevented enrollment, verification, or identification. All 35 subjects with alcohol-induced nystagmus were successfully verified and identified. There were no false verifications or false identifications. Two conditions were identified that potentially could circumvent the use of iris recognitions systems in general. Conclusions The Mobile-Eyes™ iris recognition system exhibited accurate and reliable enrollment, verification, and identification applications in this study. It may have special applications in subjects with nystagmus.
Intensity coding in primate visual system.

The pupil reflex and the discharge of LGN cells of the awake macaque were measured under stimulus conditions that yielded evidence for wide-range intensity coding in human psychophysical experiments. Ganzfeld flashes of white light were delivered under dark-adapted conditions to the surgically immobilized eye of the monkey while the other eye was observed in the infrared. Three-sec flashes elicited a consensual pupil reflex that was graded from −8 to 0 log Lamberts (L), indicating that the optic nerve fibers are capable of coding at least an 8 log-unit range of light intensity. In the physiological experiments, shorter flashes (0.1–0.5 sec) but otherwise identical conditions elicited monotonically graded responses from one type of LGN cell over the photopic range of −5 to 0 log L. Responses from other types of LGN cells were also graded over wide ranges but had different thresholds and, in some cases, nonmonotonic intensity-response functions. Latency of the excitatory LGN responses decreased with increasing intensity according to a power function with slope of −0.08. The pupil reflex and the LGN cell excitatory responses approximate power functions of light intensity with exponents of 0.22 and 0.14–0.29 respectively. The range of intensity coding found for single LGN cells is the widest yet reported for diffuse stimuli.
Comparison of the Hatch of Lymantria dispar (Lepidoptera: Lymantriidae) Eggs from Russia and the United States after Exposure to Different Temperatures and Durations of Low Temperature

Comparisons are made of the effects of temperature and duration of low temperature on egg hatch of North American and Russian gypsy moth, Lymantria dispar (L.), under controlled laboratory conditions. Percentage of hatch of embryonated eggs, days to 1st hatch after incubation at warm temperature and temporal distribution of hatch are used to compare hatch of different strains under various conditions. Eggs from 2 Russian gypsy moth strains required less exposure to low temperature to be able to hatch than did eggs from a North American strain. Hatch took longer to begin and proceeded more slowly in eggs held at constant 15 and 20°C. Hatch did not occur for >99% of North American and Russian eggs held at a constant 25°C. Substantial variation in hatch in response to low temperature exists both within and between gypsy moth strains, making adaptation to a wide range of climates possible. Variation in diapause requirements within a strain and between strains can be assessed and compared by holding eggs for 60 d at 5°C followed by incubation at 25°C.
Examining the Delayed Grief Hypothesis Across 5 Years of Bereavement

Traditional bereavement theories emphasize that it is crucial to work through the emotional meanings of a loss and that the failure to do so typically results in delayed grief symptoms. This article reports data examining these assumptions prospectively across the first 5 years of bereavement. Based on previous validity data, elevated symptoms were defined in terms of 6-month median scores for each measure. Delayed elevations were observed on isolated measures for 3 (7%) participants. However, these elevations were more parsimoniously explained by random measurement error. Furthermore, when a weighted grief-depression composite score was used to maximize the probability of capturing the true (latent) grief variable, not a single case of delayed symptom elevations was observed. Finally, data on emotional processing of the loss at 6 months failed to support the traditional assumption that minimal emotional processing of the loss would lead to delayed grief.