cssi/SciSciGPT-SciSciNet huggingface dataset:
Unseating mechanism of a skew bridge with seat-type abutments and a Simplified Method for estimating its support length requirement

Abstract In this paper, the unseating mechanism of a skewed bridge during earthquake shaking is investigated. To begin, an existed unseating mechanism in literature, which was proposed by other researchers, is described. The mechanism hypothesizes that under lateral loading, the obtuse corner of the superstructure of a skew bridge engages the adjacent back wall and the superstructure then rotates about this corner, causing large in-plane displacements at the acute corner at the other end of the span, potentially unseating the edge girder. It is then validated using data from a comprehensive set of shake table experiments recently conducted by the author and other researchers. Whereas the experimental data confirms this mechanism as the primary reason for the rotation, it is not the only reason. Impact of the span against the back wall is followed immediately by rebound away from the wall and the span continues to rotate in the same direction in free vibration about the center of stiffness of the substructure. This additional rotation further increases the superstructure rotation and the in-plane displacement of the acute corner. Based on the existed mechanism, a Simplified Method is then developed to estimate the support length requirements of skew bridges. This method, which is based on response spectrum analysis, can consider the closure of expansion gap. The basic procedures are described for the AASHTO’s design spectrum, and spectrum of an arbitrary ground motion. A closed form solution is achievable for the former spectrum, while iteration is required for the latter spectrum. The results are then compared with the experimental dataset. It is found that the accuracy of the Simplified Method depends on the gap size. That is: it overestimates the maximum displacements normal to the abutment of skew bridges when the gap is small, accurately estimates when the gap is in a typical range, and underestimates when the gap is large. The underestimation is mainly because the Simplified Method neglects the “bounce back” effect of skew bridges. Therefore, the Simplified Method may be used for the preliminary design of bridges with standard gap sizes, but should be modified to include “bounce back” effect when the gap is large.
Bad Books for Bad Readers

This chapter introduces the field of popular fiction in Arabic at the turn of the twentieth century and explores the critical discourse surrounding the novel genre and its translation through the second half of the century in Egypt. Building on a discussion of the intersections between the cultural discourses of orientalism and nationalism, the chapter examines the politics of translation in modern Arabic literary historiography of the nahda. Selim describes how the perceived “foreignness” of the novel genre according to national critics was constructed around critical and reformist anxieties about both translation and popular culture as objects of suspicion, and how national literary history effectively made a vast corpus of early Arabic fiction disappear while installing realism as the only legitimate mode of the genre.
Toward Optimization of Rheology in Sea Ice Models through Data Assimilation

AbstractSea ice models that allow for deformation are primarily based on rheological formulations originally developed in the 1970s. In both the original viscoplastic (VP) and elastic-VP schemes, t...
Anticoagulant Use Is Not Associated With Higher Post tPA Hemorrhagic Conversion (P4.240)

Objective: To explore the relationship between anti-coagulant (AC) use and hemorrhagic conversion (HC) in patients treated with iv tissue plasminogen activator (tPA) for acute ischemic stroke (AIS) in a large and representative national patient registry. Background: Even though tPA has unequivocally shown to improve outcomes in AIS, its utilization remains low due to various concerns/contraindications. Many clinicians are concerned about the risk of hemorrhage after tPA in patients on AC. Rise in AC use further increases this concern. Design/Methods: We analyzed Nationwide Inpatient Sample (NIS) and Healthcare Cost and Utilization Project (HCUP) data for years 2002–2014. We identified AIS with ICD-9-CM codes 433.xx-436, IV tPA with procedure code 99.10, and HC with ICD-9 431. AC use was identified by previously validated ICD-9-CM codes. Parametric tests and survey logistic procedure were used to analyze group comparison and multivariate regression. Results: A total of 264,643 patients with AIS received IV tPA, of which 12,690 (4.8%) were on AC prior to admission. Unadjusted, the frequency of HC was higher among AC group (9.1% v 8.0%; p Conclusions: Our study shows, AC use prior to AIS onset is not associated with higher HC with tPA use. Moreover, no significant differences in outcomes were observed in AC and ‘not on AC’ group. Being on AC should not be a prohibitive factor for tPA utilization in AIS patients. Further prospective studies, that includes precise anticoagulant measurements, are required to better understand the relationship between AC use and HC. Disclosure: Dr. Patel has nothing to disclose. Dr. Lunagariya has nothing to disclose. Dr. Patel has nothing to disclose. Dr. Jani has nothing to disclose. Dr. Nagaraja has nothing to disclose. Dr. Huisa-Garate has nothing to disclose. Dr. Hemmen has nothing to disclose.
What are the Risk Factors for Deep Infection in OTA/AO 43C Pilon Fractures?

Objectives To determine the risk factors for deep infection in OTA/AO 43C pilon fractures. Design Retrospective, case-control study. Setting Single institution, Level 1 trauma center. Participants All patients with 43C pilon fractures treated over a 5-year period with follow-up to bony union. One hundred fifty of 169 of identified patients met inclusion criteria. Intervention Operative treatment of tibial pilon fracture. Main outcome measurements Deep infection; patient demographics, Gustilo-Anderson classification, location of open fracture wounds, surgical approaches. Results The overall rate of deep infection was 16.7%. Body mass index, tobacco use, and diabetes were not associated with deep infection. The rate of Gustilo-Anderson type 3A and 3B fractures was significantly higher in those with infection, but the overall open fracture rate was not significantly different between the groups. Medial and anterior open fracture wound location was significantly associated with deep infection, whereas lateral open fracture wound location was not. In closed fractures, anteromedial and anterolateral approaches were not significantly associated with infection, but posterolateral approach was associated with deep infection. Segmental bone loss and the need for soft tissue coverage were the only independent risk factors for deep infection. Conclusions High-grade open pilon fractures are at risk of deep infection, and medial/anterior open fracture wounds are particularly vulnerable to developing deep infection. The anteromedial/anterolateral surgical approaches should be selected based on a complete understanding of the fracture pattern and soft tissue injury; however, the posterolateral approach to the tibia should be used with some caution. Ultimately injury factors (segmental bone loss and need for soft tissue coverage) seem to be the most important variables in driving deep infection, and a complete understanding of the bone and soft tissue injury is needed to manage these injuries effectively. Level of evidence Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
"The Job Is Yours!" Deconstructing the Gender Gap in Higher Education.

The underrepresentation of female Administrators in higher education is not decreasing even though education continues to be a field dominated by women. The overall percentage of women leading coll...
Childhood maltreatment and problematic alcohol use in young adulthood: the roles of cognitive vulnerability to depression and depressive symptoms.

Childhood maltreatment (CM) has been repeatedly linked to future problem drinking. Depression has been identified as a potential factor contributing to problematic alcohol use in maltreated individ...
Comparisons of venous indwelling needles and intravenous infusion with steel needles in pediatric outpatient care.

To compare the application effects of venous indwelling needles and intravenous infusion with steel needles in pediatric outpatient care and to observe the complications of the two approaches. A total of 110 children who received intravenous infusions in our hospital from March 2018 to May 2018 were selected as study subjects. Children were assigned to an observation group (n = 55) or a control group (n = 55) based on a random number table, of which the children in the control group received intravenous infusion with the steel needles while the children in the observation group received intravenous infusion with indwelling needles. Their mental states were rationally evaluated by the state-trait anxiety inventory (STAI) and modified Yale preoperative anxiety score (MYPAS) in the two groups. At the same time, the total number of punctures in 3 days of infusion, complications and the parents’ satisfaction with nursing service were compared between the two groups. The difference in STAI and MYPAS scores was statistically significant between the two groups (P 0.05) between the two groups, but the difference in the total number of punctures on the second day and the third day was statistically significant (P < 0.05). Besides this, the incidence of complications in the observation group was less than that in the control group, and the nursing satisfaction in the observation group was higher than that in the control group (P < 0.05). The children’s psychological impacts are relatively small when comparing the venous indwelling needle with the steel needle. Moreover, venous indwelling needles avoid repeated punctures; therefore, the parents’ satisfaction in nursing is improved, and it is worth popularizing.
Trends in US Heart Transplant Waitlist Activity and Volume During the Coronavirus Disease 2019 (COVID-19) Pandemic.

Importance Solid organ transplants have declined significantly during the coronavirus disease (COVID-19) pandemic in the US. Limited data exist regarding changes in heart transplant (HT). Objective To describe national and regional trends in waitlist inactivations, waitlist additions, donor recovery, and HT volume during COVID-19. Design, Setting, and Participants This descriptive cross-sectional study used publicly available data from the United Network for Organ Sharing and US Centers for Disease Control and Prevention, using 8 prespecified United Network for Organ Sharing regions. Adult (18 years or older) HT candidates listed and deceased donors recovered between January 19 to May 9, 2020. Exposures COVID-19 pandemic. Main Outcomes and Measures Changes in waitlist inactivations, waitlist additions, deceased donor recovery, and transplant volumes from the pre–COVID-19 (January 19-March 15, 2020) to the COVID-19 era (March 15-May 9, 2020). Density mapping and linear regression with interrupted time series analysis were used to characterize changes over time and changes by region. Results During the COVID-19 era, there were 600 waitlist inactivations compared with 343 during the pre-COVID era (75% increase). Waitlist additions decreased from 637 to 395 (37% reduction). These changes were most profound in the Northeast and Great Lakes regions with high rates of COVID-19. Deceased donor recovery decreased by 26% from 1878 to 1395; the most significant decrease occurred in the North Midwest despite low COVID-19 prevalence. Heart transplant volumes were significantly reduced across all regions except the Northwest. The largest decrease was seen in the Northeast where COVID-19 case rates were highest. From the pre–COVID-19 era to the COVID-19 era, there was significant regional variation in waitlist additions (eg, 69% decrease in the Northeast vs 8.5% increase in the South Midwest;P Conclusions and Relevance Heart transplant volumes have been significantly reduced in recent months, even in regions with a lower prevalence of COVID-19 cases. This has been accompanied by increased waitlist inactivations, decreased waitlist additions, and decreased donor recovery. Future studies are needed to determine if the COVID-19 pandemic is associated with changes in waitlist mortality.
Factors influencing users’ perceived value of Electronic Health Record Patient Portals:

Patient portals are websites or apps where patients can access their health information from their Electronic Health Records (EHR). This study was conducted via an online survey to identify what fa...
Using metabolic energy to quantify the subjective value of physical effort

Economists have known for centuries that to understand an individual's decisions, we must consider not only the objective value of the goal at stake, but its subjective value as well. However, achieving that goal ultimately requires expenditure of effort. Surprisingly, despite the ubiquitous role of effort in decision-making and movement, we currently do not understand how effort is subjectively valued in daily movements. Part of the difficulty arises from the lack of an objective measure of effort. Here, we use a physiological approach to address this knowledge gap. We quantified objective effort costs by measuring metabolic cost via expired gas analysis as participants performed a reaching task against increasing resistance. We then used neuroeconomic methods to quantify each individual's subjective valuation of effort. Rather than the diminishing sensitivity observed in reward valuation, effort was valued objectively, on average. This is significantly less than the near-quadratic sensitivity to effort observed previously in force-based motor tasks. Moreover, there was significant inter-individual variability with many participants undervaluing or overvaluing effort. These findings demonstrate that in contrast with monetary decisions in which subjective value exhibits diminishing marginal returns, effort costs are valued more objectively in low-effort reaching movements common in daily life.
Sexuality Education Programs for Youth: Current State of Affairs and Strategies for the Future

The topic of sexuality education for youth or what society teaches our youth about their sexuality, is a subject of paramount importance. Most states have some form of comprehensive sexuality education managed at the state level. Most American adolescents, adults, educators, and parents support sexuality education in the public schools. This paper reviews the literature on sexuality education for youth and concludes that carefully structured sexuality education programs can modify adolescents' sexual behavior and increase adolescents' understanding of moral behavior.
Use of yeast artificial chromosomes to express genes in transgenic mice.

Publisher Summary This chapter focuses on the purification of yeast artificial chromosomes (YAC) DNA for the production of transgenic mice by microinjection of fertilized oocytes and the analysis of YAC transgene structure in mice. The chapter outlines the manipulations of YACs in yeast. Generation of transgenic mice with YACs and other large molecules has proved to be a valuable system for studies of gene structure-function relationships, production of mouse models of human disease, complementation of mouse mutants, use of mice as bioreactors, and synthesis of in vivo YAC libraries. Continued refinements of current techniques and development of new protocols should encourage widespread adaptation of this strategy for the aforementioned applications. Use of whole loci as transgenes is an important improvement as the advent of murine transgenesis, one that may allow a more realistic assessment of gene regulatory mechanisms during development.
Failure of Escherichia coli to Alter Its Fatty Acid Composition in Response to Cholesterol-Induced Changes in Membrane Fluidity

Substantial amounts of exogenously supplied cholesterol were incorporated into the membranes of Escherichia coli during growth and caused a large decrease in membrane fluidity. Although no compensatory changes in fatty acid composition were observed, the incorporation of cholesterol did not affect the rate of growth of E. coli or interfere with the changes in fatty acid composition which normally occur during growth at different temperatures.
Small RNA regulation of a multidrug efflux pump (750.1)

Multidrug efflux pumps are a major mechanism used by bacteria to export drugs and toxic compounds from the cell. One of the most important efflux pumps in E. coli is the AcrAB-TolC system. In E. co...
Sea‐ice reemergence in a model hierarchy

Lagged correlation analysis of Arctic sea-ice area reveals that melt season sea-ice anomalies tend to recur the following growth season, and growth season anomalies tend to recur the following melt season. In this work, a climate model hierarchy is used to investigate the relative role of the atmosphere and the ocean in driving this phenomenon, termed sea-ice reemergence. The covariability of sea-ice concentration (SIC), sea surface temperature (SST), and sea level pressure (SLP) is studied via coupled nonlinear Laplacian spectral analysis, and families of modes that capture reemergence are constructed. In model configurations with ocean-to-atmosphere coupling, these “reemergence families” display a pan-Arctic scale organization of SIC anomalies, related to SLP teleconnection patterns. The ocean is found to provide the key source of memory for reemergence, as an SST-based reemergence mechanism can operate as a stand-alone process, while an SLP-based mechanism cannot. Dynamical feedback from the ocean to the atmosphere is found to be essential in creating large-scale organized patterns of SIC-SLP covariability.
Sub-millisecond thermal impedance and steady state thermal resistance explored [power MOSFETs]

Thermal characterization of semiconductor devices has been ongoing in laboratories for the last forty years and techniques are well known. However, given the dated equipment that many manufacturers use, it is debatable whether these techniques are accurate. This paper (1) explores thermal impedance and thermal resistance measurement methods for power MOSFETs; (2) investigates test system measurement errors and a new test circuit for evaluation of transient pulse widths of 1 ms and narrower; (3) shows that not all characterization heat sinks are created equal.
The Year in Review: The Thyroid

Several studies that have important implications for the management of patients with various thyroid disorders were recently published. These studies concern screening for thyroid disease, thyroid eye disease and treatment with iodine-131, antithyroid drug treatment, treatment of hypothyroidism, and management of thyroid nodules. For each topic, the results of the studies are presented and recommendations for their translation into clinical practice are offered.
Single chloride-selective channel from cardiac sarcoplasmic reticulum studied in planar lipid bilayers

The behavior of single Cl− channel was studied by fusing isolated canine cardiac sarcoplasmic reticulum (SR) vesicles into planar lipid bilayers. The channel exhibited unitary conductance of 55 pS (in 260mm Cl−) and steady-state activation. Subconductance states were observed. Open probability was dependent on holding potentials (−60 to +60 mV) and displayed a bell-shaped relationship, with probability values ranging from 0.2 to 0.8 with a maximum at −10 mV. Channel activity was irreversibly inhibited by DIDS, a stilbene derivative. Time analysis revealed the presence of one time constant for the full open state and three time constants for the closed states. The open and the longer closed time constants were found to be voltage dependent. The behavior of the channel was not affected by changing Ca2+ and Mg2+ concentrations in both chambers, nor by adding millimolar adenosine triphosphate, or by changing the pH from 7.4 to 6.8. The presence of sulfate anions decreased the unit current amplitude, but did not affect the open probability. These results reveal that at the unitary level the cardiac SR anion-selective channel has distinctive as well as similar electrical properties characteristic of other types of Cl− channels.
Prostate specific antigen recurrence after definitive therapy.

Purpose: We estimate that approximately 70,000 men yearly have prostate specific antigen-only recurrence after failed definitive therapy. The ideal salvage therapy for these men is not clear. Treatment must be individualized based on the patient risk of progression, the likelihood of success and the risks involved with the therapy. However, to do so the risks and benefits of the various options must be known. Therefore, we provide a comprehensive overview of the natural history and treatment options for men with prostate specific antigen-only recurrence.Materials and Methods: A literature review and overview of prostate specific antigen-only recurrence after failed definitive therapy was done.Results: The natural history after prostate specific antigen-only recurrence is long but variable. Median time from prostate specific antigen-only recurrence after radical prostatectomy to prostate cancer death exceeds 16 years, although some men die within 1 year after PSA recurrence. Rapid prostate specific antigen...
On one-way cellular arrays

There are two simple models of parallel language recognizes: one-way cellular array (OCA) and one-way iterative array (OIA). For inputs of length n, both arrays consist of n identical finite-state machines (cells). The communication between cells is one way, from left to right. The difference in the two models is in the manner in which the input is applied. For the OCA, the input is applied to the cells in parallel. For the OIA, the input is applied serially to the leftmost processor. An input string is accepted if the rightmost cell eventually enters an accepting state. We show that OCA’s accept exactly the same class of languages as OIA’s. It is relatively easy to show that OIA’s can simulate OCA’s. The difficult part is the converse, i.e., that OCA’s can simulate OIA’s. This is rather surprising, since in an OIA, every cell of the array has access to each symbol of the input string, whereas in an OCA, the ith cell can only access the first i symbols of the input. This result, when combined with known r...
Behavioral and neurochemical effects of Δ9-tetrahydrocannabinol in rats

Abstract Effects of Δ 9 -tetrahydrocannabinol (Δ 9 -THC) were studied on self-stimulation (SS) behavior in rats with electrodes implanted at either the posterior hypothalamus (PH) or area ventralis tegmentum (A10 area). Its effects were also studied on spontaneous motor activity (SMA), rectal temperature, barbiturate sleeping time, and neurotransmitter levels in discrete brain areas. Two patterns of Δ 9 -THC effects were observed in these experiments. One type consisted of gradual depression persisting over a prolonged period. Hypothermia, potentiation of barbiturate-induced sleep and decrease in SS responding to nonaroused subjects, are examples. These effects may be due to a generalized central depression. The other type, a triphasic effect, is characterized by an initial depression followed by a stimulation and then again depression, and was observed in SS in aroused subjects and also in SMA. The effects of the psychomotor stimulants (such as amphetamine and cocaine) were antagonized during the initial depressant phase and unaffected or even potentiated during the subsequent stimulant phase. The neurochemical studies demonstrated an initial decrease of dopamine (DA) levels in the caudate nucleus and diencephalon-midbrain (DM) and an increase of serotonin (5-HT) in DM and pons-medulla (PM) followed by an increase of DA and a decrease of 5-HT levels, and then their return to near normal levels in respective brain areas. These changes in neurotransmitter levels appear to be correlated to the triphasic behavioral effects.
Optimal Two-Machine Orderings in the 3 × n Flow-Shop Problem

Consider the 3 × n flow-shop problem with machines A, B, and C. By AB and BC optimum we mean optimal solutions produced by Johnson's method for the two-machine problems AB and BC, respectively. Although not every permutation that is an AB and BC optimum simultaneously is an optimal solution of the entire problem, the set P of such permutations does contain an ABC optimum whenever it is not empty. We summarize known analytical results and solution procedures for the 3 × n flow-shop problem.
GABA and dopamine receptor binding in retinal synaptosomal fractions

Binding sites for a variety of agonists and anatagonists of GABA and dopamine were demonstrated in retina subcellular fractions. These sites exhibited the binding kinetics and pharmacologic specificity consistent with known properties of the physiological receptors for GABA and for dopamine. Important differences noted between brain and retinal receptors will be discussed.
Maltose-binding protein fusion allows for high level bacterial expression and purification of bioactive mammalian cytokine derivatives.

Fusokines are chimeric proteins generated by the physical coupling of cytokines in a single polypeptide, resulting in proteins with highly pleiotropic activity and the potential to treat cancer and autoimmune ailments. For instance, the fusokine GIFT15 (GM-CSF and Interleukin 15 Fusion Transgene) has been shown to be a powerful immunosuppressive protein able to convert naive B cells into IL-10-producing B cells. To date, the mammalian cell systems used for the expression of GIFT15 allow for secretion of the protein in the culturing media, an inefficient system for producing GMP-compliant fusokines. In this study we report the bacterial expression of bioactive recombinant GIFT15 (rGIFT15). Indeed, there is a constant demand to improve the expression systems for therapeutic proteins. Expression of a maltose-binding protein (MBP) fusion protein efficiently allowed the accumulation of soluble protein in the intracellular milieu. Optimizing the bacterial culture significantly increased the yield of recombinant protein. The biological activity of rGIFT15 was comparable to that of fusokine derived from a mammalian source. This approach led to the production of soluble, endotoxin-free functional protein, averaging 5 mg of rGIFT15 per liter of culture. This process is amenable to scale up for the development of Food and Drug Administration (FDA)-compliant immune-modulatory rGIFT15.
Recovery and refining of rhenium, tungsten and molybdenum from W-Re, Mo-Re and other alloy scraps

Abstract The extensive use of rhenium in fabricating high temperature alloys, its use as a catalyst in a variety of applications, its high cost and its rarity are important incentives for developing techniques for its recovery. The recycling and recovery of tungsten and molybdenum is also essential because of their increasing use in high temperature alloys, metal carbides, cutting and drilling tools, and a variety of other applications. We developed a simple recovery method in which the scrap is oxidized by pure oxygen gas at 1000 °C and the resulting volatile rhenium oxide is condensed in the cooler region of the reaction chamber. This oxide is dissolved in water and treated with potassium chloride to form its potassium salt which is reduced under hydrogen gas to pure rhenium metal powder. The oxides of tungsten or molybdenum are treated with boiling water, dried and reduced under hydrogen to their respective pure metal powders. All three metal powders are of high purity and fine size. The method is simple and economical and does not generate any acid, wastes or other environmental pollutants.
Team Skill Acquisition: Team and Individual Performance Effects of Feedback

Although team development research has, to some extent, addressed the various components of team functioning, later studies have failed to sufficiently clarify what influences teams as they acquire the various skills that constitute complex team performance. Similarly, research regarding team structure, as of yet, has failed to fully determine how teams under various structures should be trained in order to optimize their ability to perform complex (i.e., both team and individual) tasks. Thus, there is a need to investigate differential developmental trends in teams of varying structure. Additionally, research is required to identify interventions which might optimize the developmental process. Although the effects of feedback are becoming increasingly well investigated, there has been relatively little investigation regarding the impact of feedback given on multiple task performance. The current study investigates the impact of feedback given, over time, regarding team vs. individual tasks in teams of tw...
Spectral polarimetry for assessing cell alignment in cultured tissues

Successful development of cultured tissues is heavily influenced by cell alignment within the tissue scaffold. Proper cell alignment leads to optimum tissue strength. It has been demonstrated that proper alignment is engendered by application of physiologically realistic stresses during the cell proliferation process. In situ monitoring of cell alignment during development thus can provide important feedback information in determining the optimum stresses. T-matrix calculations suggest that cell alignment characteristics (cell aspect and orientation) can be inferred from the spectral polarization of light scattered by the cells. Therefore, a spectral polarimetry system has been created to measure these effects to provide feedback for proper cell alignment. In order to properly use the system, a calibration procedure was first established. The calibration procedure entailed making mathematical predictions for the system performance based on the system components, and then empirically validating these predictions. Upon system calibration, measurements were made on a biologically relevant sample. We present results of experimental measurements on the sample and discuss structural inferences made from these measurements. In addition, we compare our results with structural information obtained from histological analysis.
A sensitivity analysis of the smith predictor controller

Abstract The sensitivity of the Smith predictor controller to variations in system parameters is analyzed. The parameters considered are system gain, time constant, and delay or dead time. Both simulated and experimental results are discussed. First- and second-order models are studied. For the first-order model, a proportional plus integral control is used with the Smith predictor. A proportional plus integral plus derivative control is used with the Smith predictor for the second-order system. The controller is implemented digitally. An application of the Smith predictor with a model of the system obtained by a nonlinear least-squares parameter identification method is demonstrated on an experimental system.
Developments in the use of spectral signature for mapping the surface of solar system objects other than the Earth

Abstract The spectral character of diffusely reflected sunlight has been used in the study of the surfaces of solar system objects other than the Earth for decades. But only in the past 10 to 15 years has the spectral resolution and coverage and the radiometric precision become sufficient to provide definitive results. Two approaches are used: (1) spectroscopy and (2) multispectral mapping. In spectroscopy (1) the reflectance spectrum is measured in the spectral region with extreme limits of about 0.20 μm to 5 μm and with spectral precision (Δλ/λ) of about 0.1 to 0.01 and radiometric precision better than a percent in many cases. Electronic and molecular absorptions occur in this region for many solids and they often can be interpreted as indicating the presence and to some extent the amount of certain minerals. This information allows the surface materials to be characterized. (2) Knowledge of the spectrum of surface regions and of the spectral properties of materials are used to choose a few select bandpasses within which to image surface regions. Multispectral maps are generated from these images and are used to define the extent of surface units. This definition and characterization of surface units allows the production of a kind of geologic map which is used to help reveal the evolution and present structure and composition of the planet or satellite. Laboratory and theoretical analysis of the optical properties of materials are an essential ingredient in designing a remote sensing experiment of this sort and interpreting the data. These techniques are being used to study most of the solar system objects with visible surfaces from the moon and Mars, for which the most complete analysis have been performed, to asteroids, and Galilean satellites for which only hemispheric spatial resolution exist. Groundbased, airborne, earth-orbital and space-probe platforms are all used to acquired data. State-of-the-art spectrometers and imaging systems are in use at groundbased telescopes; the time period required to bring a spacecraft mission to completion has delayed the instrument technology utilization in this area. Data processing facilities are being taxed as more sophisticated instruments are used and more rapid turn-around times are required. Reflection spectroscopy and multispectral mapping, especially when used in conjunction with other remote sensing data, have proved to be very important tools for studying the structure and composition of surface units. Several example applications will be discussed to illustrate both the methods and the rewards.
Calibrating thermal imagery from an unmanned aerial system - AggieAir

Small unmanned aerial systems (UAS) can be very useful for acquiring high resolution thermal imagery for many ecological applications. With these systems, routine ground sampling is important in order to calibrate the imagery and to understand unique environmental disturbances. Simple, accurate methods to sample surface temperature is needed. This paper introduces two methods for sampling ground surface temperatures. One method uses a ground-based thermal camera to capture a high-resolution sample of a small area. The other method uses temperature controlled pools, which can be seen from the aerial thermal image. These samples are used to calibrate a thermal mosaic captured by the UAS AggieAir. Accuracy and simplicity are evaluated for each method.
Human Langerhans cells use an IL-15R-α/IL-15/pSTAT5-dependent mechanism to break T-cell tolerance against the self-differentiation tumor antigen WT1

Human CD34+ progenitor-derived Langerhans-type dendritic cells (LCs) are more potent stimulators of T-cell immunity against tumor and viral antigens in vitro than are monocyte-derived DCs (moDCs). The exact mechanisms have remained elusive until now, however. LCs synthesize the highest amounts of IL-15R-α mRNA and protein, which binds IL-15 for presentation to responder lymphocytes, thereby signaling the phosphorylation of signal transducer and activator of transcription 5 (pSTAT5). LCs electroporated with Wilms tumor 1 (WT1) mRNA achieve sufficiently sustained presentation of antigenic peptides, which together with IL-15R-α/IL-15, break tolerance against WT1 by stimulating robust autologous, WT1-specific cytolytic T-lymphocytes (CTLs). These CTLs develop from healthy persons after only 7 days' stimulation without exogenous cytokines and lyse MHC-restricted tumor targets, which include primary WT1+ leukemic blasts. In contrast, moDCs require exogenous rhuIL-15 to phosphorylate STAT5 and attain stimulatory capacity comparable to LCs. LCs therefore provide a more potent costimulatory cytokine milieu for T-cell activation than do moDCs, thus accounting for their superior stimulation of MHC-restricted Ag-specific CTLs without need for exogenous cytokines. These data support the use of mRNA-electroporated LCs, or moDCs supplemented with exogenous rhuIL-15, as vaccines for cancer immunotherapy to break tolerance against self-differentiation antigens shared by tumors.
Facile and Efficient Acetylation of Primary Alcohols and Phenols with Acetic Anhydride Catalyzed by Dried Sodium Bicarbonate

A variety of primary alcohols and phenols were reacted with acetic anhydride at room temperature in the presence of sodium bicarbonate to produce corresponding esters in good to excellent yields. The acetylation of 4-nitrobenzyl alcohol was also carried out using other bicarbonates and carbonates. The reaction in the presence of cesium bicarbonate and lithium carbonate gave 4-nitrobenzyl acetate in excellent yield, while in the presence of Na2CO3, K2CO3, Cs2CO3, or KHCO3 the yield was in the range of 80%–95%. Calcium carbonate and cobaltous carbonate did not promote the acetylation of 4-ntirobenzyl alcohol using acetic anhydride. The acetylation of 4-nitrobenzyl alcohol was carried out using ethyl acetate, THF, toluene, diethyl ether, dichloromethane and acetonitrile, and gave good yields ranging from 75%–99%. Toluene was the best solvent for the reaction, while diethyl ether was the poorest.
The role of patient personality in the identification of depression in older primary care patients.

Background Our aim was to evaluate whether personality factors significantly contribute to the identification of depression in older primary care patients, even after controlling for depressive symptoms. Methods We examined the association between personality factors and the identification of depression among 318 older adults who participated in the Spectrum study. Results High neuroticism (unadjusted Odds Ratio (OR) 2.36, 95% Confidence Interval (CI) [1.42, 3.93]) and low extraversion (adjusted OR 2.24, CI [1.26, 4.00]) were associated with physician identification of depression. Persons with high conscientiousness were less likely to be identified as depressed by the doctor (adjusted OR 0.45, CI [0.22, 0.91]). Conclusion Personality factors influence the identification of depression among older persons in primary care over and above the relationship of depressive symptoms with physician identification. Knowledge of personality may influence the diagnosis and treatment of depression in primary care. Copyright © 2007 John Wiley & Sons, Ltd.
Mid-wavelength infrared p-on-n Hg1-xCdxTe heterostructure detectors: 30-120 kelvin state-of-the-art performance

We report on Hg1−xCdxTe mid-wavelength infrared (MWIR) detectors grown by molecular-beam epitaxy (MBE) on CdZnTe substrates. Current-voltage (I-V) characteristics of HgCdTe-MWIR devices and temperature dependence of focal-plane array (FPA) dark current have been investigated and compared with the most recent InSb published data. These MWIR p-on-n Hg1−xCdxTe/CdZnTe heterostructure detectors give outstanding performance, and at 68 K, they are limited by diffusion currents. For temperatures lower than 68 K, in the near small-bias region, another current is dominant. This current has lower sensitivity to temperature and most likely is of tunneling origin. High-performance MWIR devices and arrays were fabricated with median RoA values of 3.96 × 1010 Ω-cm2 at 78 K and 1.27 × 1012 Ω-cm2 at 60 K; the quantum efficiency (QE) without an antireflection (AR) coating was 73% for a cutoff wavelength of 5.3 µm at 78 K. The QE measurement was performed with a narrow pass filter centered at 3.5 µm. Many large-format MWIR 1024 × 1024 FPAs were fabricated and tested as a function of temperature to confirm the ultra-low dark currents observed in individual devices. For these MWIR FPAs, dark current as low as 0.01 e−/pixel/sec at 58 K for 18 × 18 µm pixels was measured. The 1024 × 1024 array operability and AR-coated QE at 78 K were 99.48% and 88.3%, respectively. A comparison of these results with the state-of-the-art InSb-detector data suggests MWIR-HgCdTe devices have significantly higher performance in the 30–120 K temperature range. The InSb detectors are dominated by generation-recombination (G-R) currents in the 60–120 K temperature range because of a defect center in the energy gap, whereas MWIR-HgCdTe detectors do not exhibit G-R-type currents in this temperature range and are limited by diffusion currents.
Sarcoidosis of the pancreas

We report a case of pancreatic sarcoidosis in a patient with radiographic and clinical findings suggestive of pancreatic cancer. Clinically apparent involvement of the pancreas is uncommon in patients with known sarcoidosis and is distinctly unusual as the initial presentation of disease. Sarcoid involvement of the pancreas can mimic adenocarcinoma and should be considered in the differential diagnosis of a pancreatic mass in a patient with symptoms suggestive of sarcoidosis. © 1993 Wiley-Liss, Inc.
Field and spatial geometry dependencies of the electron and hole ionization rates in GaAs/AlGaAs multiquantum well APD's

Numerical calculations are presented of the electron and hole ionization rates in GaAs/AlGaAs multiquantum-well APDs (avalanche photodiodes) as a function of the applied electric field and the spatial geometries, i.e., the barrier- and well-layer widths, respectively. The model is calibrated to existing experimental data on bulk GaAs materials and then extrapolated to the multiquantum well structure. It is found that at high electric field strengths the net ionization rate approaches the weighted average of the constituent bulk rates; the potential discontinuity is relatively insignificant. The potential discontinuity most greatly affects the electron ionization rate at low applied electric field strengths within a spatially symmetric structure. It is further determined that the electron-to-hole ionization rate ratio is greatest at low applied electric fields with a spatially symmetric structure with equal well and barrier widths. >
Key challenges in securing WiMAX mesh networks

Worldwide interoperability for microwave access (WiMAX), designed by the IEEE 802.16 standards group, is one of the most promising broadband wireless technologies with respect to delivering high-speed connectivity in the last mile. A mesh network configuration was added for improved coverage and throughput. We describe security concerns for WiMAX mesh mode such as malicious sponsor nodes and privacy. We also seek to reduce the processing load as a result of the use of link encryption. We introduce two different types of attacks as a result of different types of malicious sponsor nodes. The first type of attack occurs when the malicious sponsor node has not actually joined the current mesh network but solicits new nodes to join the mesh network through it. The second type of attack occurs when the malicious node is a member of the mesh network and selectively drops data from its child nodes. To prevent the first attack, we propose a new security protocol that adds to the standard control messages a pair of secret authorization keys (AK). To handle the second attack, we propose a reputation-based scheme that is specific to WiMAX mesh networks. We conduct a numerical analysis and simulations to highlight the strengths of the proposed schemes. The proposed reputation-based scheme uses the MSH-NCFG control message that is used in the WiMAX standard to send reputation information about nodes in the mesh network. Nodes that are joining the mesh network receive and process MSH-NCFG messages and decide which sponsor node through which to join the network. We conduct a numerical analysis to determine the amount of time for reputation information to propagate through the mesh network, thus allowing joining nodes to avoid malicious sponsor nodes. The simulation results show that the proposed scheme can reduce the overall data drop rate in WiMAX mesh networks in the presence of the aforementioned attacks from malicious sponsor nodes. Copyright © 2009 John Wiley & Sons, Ltd.
Ice-front variation and tidewater behavior on Helheim and Kangerdlugssuaq Glaciers, Greenland

We used satellite images to examine the calving behavior of Helheim and Kangerdlugssuaq Glaciers, Greenland, from 2001 to 2006, a period in which they retreated and sped up. These data show that many large iceberg-calving episodes coincided with teleseismically detected glacial earthquakes, suggesting that calving-related processes are the source of the seismicity. For each of several events for which we have observations, the ice front calved back to a large, pre-existing rift. These rifts form where the ice has thinned to near flotation as the ice front retreats down the back side of a bathymetric high, which agrees well with earlier theoretical predictions. In addition to the recent retreat in a period of higher temperatures, analysis of several images shows that Helheim retreated in the 20th Century during a warmer period and then re-advanced during a subsequent cooler period. This apparent sensitivity to warming suggests that higher temperatures may promote an initial retreat off a bathymetric high that is then sustained by tidewater dynamics as the ice front retreats into deeper water. The cycle of frontal advance and retreat in less than a century indicates that tidewater glaciers in Greenland can advance rapidly. Greenland's larger reservoir of inland ice and conditions that favor the formation of ice shelves likely contribute to the rapid rates of advance.
3D Heteronuclear long-range 1H–13C scalar correlation at natural abundance: application to oligosaccharide analysis

A 3D 1H–13C–1H refocused INEPT transfer experiment is proposed in which the initial coherence transfer of 1H longitudinal to 13C transverse magnetization is tuned to the long-range 1H, 13C couplings while the reverse INEPT component transfers the magnetization to the directly bonded 1H. Integration of a constant time 1H evolution period into the long-range coherence transfer interval provides absorption mode signals for each dimension. A 13C purge component at the beginning of the sequence selects for 12C-bound 1H magnetization that is then transferred to a 13C-bound hydrogen, thus strongly suppressing the diagonal signals. This experiment is expected to be of particular value for situations in which resonance overlap in the 13C dimension renders 2D long-range heteronuclear correlation data ambiguous. In combination with a diagonal-suppressed 3D 1H–13C–1H TOCSY-HSQC experiment, complete assignment of the ring resonances of the Lewis-b hexasaccharide was obtained on a 4.2 mM sample using a conventional 500 MHz probe (0.1% ethylbenzene signal-to-noise ratio of 600), suggesting its applicability to sub-millimolar samples using cryoprobe technology. Copyright © 2002 John Wiley & Sons, Ltd.
Hypercalciuric Response to Dietary Supplementation with DL-Methionine and Ammonium Sulfate

Abstract Renal Ca and inorganic P (Pi) excretion were evaluated in Single Comb White Leghorn pullets reared on diets containing 1 or 3.5% Ca alone or supplemented with .6% DL-methionine or .53% ammonium sulfate. Plasma and urine samples were collected during a CONTROL period, and while 200 mM Ca was infused intravenously (Ca-LOADING). Excess Ca, whether supplied chronically in the feed or infused acutely into birds fed 1% Ca diets, significantly reduced glomerular filtration rates, effective renal plasma flow rates, and Pi excretion rates and significantly increased Ca excretion rates and urine pH. Birds fed diets supplemented with DL-methionine and ammonium sulfate maintained significantly lower plasma Ca concentrations during the CONTROL and Ca-LOADING periods than birds fed the respective 1 or 3.5% Ca basal diets. When compared with birds fed the respective 1 or 3.5% Ca basal diets, birds fed the 1% Ca diet supplemented with ammonium sulfate or the 3.5% Ca diet supplemented with DL-methionine had significantly higher absolute urinary Ca excretion rates during Ca-LOADING. Fractional Ca excretion during Ca-LOADING was significantly higher in birds fed 3.5% Ca supplemented with DL-methionine or ammonium sulfate than in birds fed the 3.5% Ca basal diet. These results indicate that DL-methionine and ammonium sulfate accelerated urinary Ca excretion and reduced Ca retention in the extracellular fluid. The hypercalciuric efficacies of DL-methionine and ammonium sulfate were revealed only when the filtered load of Ca was increased through intravenous Ca infusions.