cssi/SciSciGPT-SciSciNet huggingface dataset:
Chapter 57 – Exocrine Pancreas

The exocrine pancreas is strategically located in the anterior abdominal cavity adjacent to the stomach, duodenum, and liver to enable secretion of digestive enzymes into the small intestine, and to convert ingesta into absorbable proteins, carbohydrates, and lipids. Additionally, it provides a scaffold, or foundation, and microenvironment for pancreatic islet cells, which provide the embedded endocrine function of the pancreas that enables hepatic and peripheral tissue modulation of blood glucose, among other functions. In spite of its close proximity to the small intestine and potentially toxic ingesta, its unique function in producing digestive enzymes, and proximity to the common bile duct containing bile salts and acids, it is seldom a prominent target of toxicity studies. Individual case reports in humans and animals, in concert with epidemiologic studies published in medical journals, provide insight into risks of pancreatic toxicity as either idiosyncratic events with few subsequent reports, or consistent reproducible mechanisms of action that closely link exposure to drugs or xenobiotics to both acute and chronic pancreatitis. Epidemiologically, pancreatic injury has been associated with a range of environmental pollutants and with consumption of mycotoxins, and has longstanding links to alcoholism and smoking tobacco. These examples highlight the need for biomarkers that are predictive of early onset of pancreatic injury as well as the clinical outcome for the individual.
A second-generation glucagon-like peptide-1 receptor agonist mitigates vomiting and anorexia while retaining glucoregulatory potency in lean diabetic and emetic mammalian models

Aim To develop a conjugate of vitamin B12 bound to the glucagon-like peptide-1 receptor (GLP-1R) agonist exendin-4 (Ex4) that shows reduced penetrance into the central nervous system while maintaining peripheral glucoregulatory function. Methods We evaluated whether a vitamin B12 conjugate of Ex4 (B12-Ex4) improves glucose tolerance without inducing anorexia in Goto-Kakizaki (GK) rats, a lean type 2 diabetes model of an understudied but medically compromised population of patients requiring the glucoregulatory effects of GLP-1R agonists without anorexia. We also utilized the musk shrew (Suncus murinus), a mammalian model capable of emesis, to test B12-Ex4 on glycaemic profile, feeding and emesis. Results In both models, native Ex4 and B12-Ex4 equivalently blunted the rise in blood glucose levels during a glucose tolerance test. In both GK rats and shrews, acute Ex4 administration decreased food intake, leading to weight loss; by contrast, equimolar administration of B12-Ex4 had no effect on feeding and body weight. There was a near absence of emesis in shrews given systemic B12-Ex4, in contrast to reliable emesis produced by Ex4. When administered centrally, both B12-Ex4 and Ex4 induced similar potency of emesis, suggesting that brain penetrance of B12-Ex4 is required for induction of emesis. Conclusions These findings highlight the potential therapeutic value of B12-Ex4 as a novel treatment for type 2 diabetes devoid of weight loss and with reduced adverse effects and better tolerance, but similar glucoregulation to current GLP-1R agonists.
Effects of surface roughness and albedo on depolarization in Mueller matrices

The Mueller matrix dependence on an objects' albedo and surface texture are measured and these effects are used to inform modifications to a microfacet model for polarized light scattering. Four different textures are imparted on red LEGO bricks which are illuminated at 451 nm and 662 nm. These wavelengths yield measurements for both low and high albedo conditions respectively. Analysis of polarizance, depolarization index, polarization entropy, and matrix roots demonstrate that texture and albedo have distinct polarization and depolarization signatures. The root mean square deviations (RMSD) of the unmodified microfacet model from the measurements are about three times greater for high albedo compared to low albedo measurements. The surface texture trend is more subtle, but in all cases the RMSD decreases as roughness increases. A major contribution of this work is an adjustment to the microfacet model so that the polarized term is wavelength dependent. This adjusted model improves the RMSD more for the low albedo compared to the high albedo measurements. To improve model fits to high albedo measurements, a modified depolarization structure is introduced to reduce the RMSD of high albedo measurements by about a factor of two.
Thick 4H-SiC epitaxial detectors for high-resolution radiation detection in harsh environment

We report on the fabrication and characterization of a high-resolution Schottky barrier radiation detector for high temperature (HT) applications using high quality 150 &#120583;m thick n-4H-SiC epitaxial layers with an ultra-low micropipe density of ≤0.1 cm-2. To evaluate the depletion region parameters of the detector, it was first characterized temperature- dependent capacitance voltage (C-V-T) measurements which showed barrier heights Φ&#119861; ranging from 2.09 to 2.24 eV and a carrier concentration of ~2 x 1014 cm-3 at room temperature (RT) which linearly increased at a rate of 9.65 x 1010 cm-3/K. From the depletion region simulation studies, it was shown that the change in doping concentration with temperature (T) can increase the needed bias to fully capture charged particles by up to 9V for 241Am and over 30V for a higher energy particles from 213Po. To examine the barrier properties and leakage currents of the detectors, we have systematically characterized temperature-dependent current - voltage measurements (I-V-T). The forward bias characteristics showed two linear regions - a low voltage region corresponding to a Shockley-Read-Hall (SRH) recombination center at &#119864;&#119862; − 0.93 eV and an upper region which corresponded to the barrier height of 2.02 eV. The reverse bias leakage currents were measured to be ~6 pA at ~65V at 300K implying a high signal to noise ratio (SNR) at RT and exhibited a current of less than 1 nA until 500K suggesting that detector should be operable with high SNR at ~200 oC. The Arrhenius plot of the reverse I-V-T showed an activation energy of 0.11 eV up to 400K and then 0.73 eV for 450K to 600K suggesting that most of the excess current at HT is derived from deep level state Z1/2 recombination center. Deep level transient spectroscopy (DLTS) results showed low defect concentrations of ~1011 cm-3 confirming that charge loss from trapping is negligible. Density functional theory (DFT) calculations suggested that the measured trap levels corresponded primarily to carbon (C) vacancies while the level at 0.93 eV corresponded to Si vacancies near the surface. The pulse height spectra (PHS) of the detector showed an excellent RT energy resolution of 0.55% FWHM at 5486 keV alpha particles after gaussian correction owed gamma response at 59.54 keV.
A Survey-Based Study of Patient-Centered Costs Associated With Indwelling Pleural Catheters.

Introduction:Indwelling pleural catheters (IPC) are effective at palliating benign and malignant pleural effusions (MPE). They have also been found to be cost effective from a third-party payor per...
Association of Positional Plagiocephaly and Developmental Delay Within a Primary Care Network.

Objective Previous research has suggested an association between plagiocephaly and developmental delay. However, study samples drawn from children seen in subspecialty clinics increase the potential for selection and referral bias. Our study evaluates the association between plagiocephaly and developmental delay and the timing of these diagnoses in a primary care setting, where plagiocephaly is commonly diagnosed and managed. Methods Our retrospective analysis used electronic medical record data from 45 primary care sites within a children's health system from 1999 to 2017, including children aged 0 to 5 years with diagnoses determined by physician diagnosis codes at primary care visits. Children were classified in the plagiocephaly group if diagnosis occurred by 12 months of age. Primary outcome was any developmental delay. Pearson χ2 test, Fisher exact test, and logistic regression analyses were conducted, with multivariable models adjusted for sex, race, ethnicity, insurance, prematurity status (22-36 weeks' gestation), primary care sites, birth year, and diagnoses of abnormal tone and torticollis. Results Of 77,108 patients seen by 12 months, 2315 (3.0%) were diagnosed with plagiocephaly, with an increase in diagnosis prevalence over the study time frame. Plagiocephaly was independently associated with an increased odds of any developmental delay diagnosis (adjusted odds ratio 1.50, 95% confidence interval 1.32-1.70). The diagnosis of plagiocephaly was recorded before the diagnosis of developmental delay in most cases when both diagnoses were present (374 of 404, 92.6%). Conclusion Data from a large primary care cohort demonstrate an association between plagiocephaly and developmental delay, affirming findings in previous subspecialty literature.
Outcomes of Pars Plana Vitrectomy Alone versus Combined Scleral Buckling plus Pars Plana Vitrectomy for Primary Retinal Detachment.

Purpose We compared the outcomes of primary uncomplicated rhegmatogenous retinal detachment (RRD) repair using pars plana vitrectomy (PPV) alone versus combined scleral buckling plus PPV (SB+PPV). Design Retrospective, observational study. Participants Patients with primary RRD who underwent PPV or SB+PPV from June 1, 2014, through December 31, 2017. Methods We performed a single-institution, retrospective, observational study of 488 consecutive patients with primary RRD repaired via PPV alone or SB+PPV and gas tamponade. We excluded patients younger than 18 years and those with advanced proliferative vitreoretinopathy, giant retinal tear, trauma, or secondary forms of RRD. We performed logistic regression and Cox proportional hazard regression analyses to identify potential risk factors associated with a retinal redetachment. Main Outcome Measures Single-operation anatomic success (SOAS), defined as adequate retinal reattachment achieved with only 1 procedure. Results The mean follow-up interval was 14.3 months. Single-operation anatomic success and final anatomic success were achieved in 425 eyes (87.1%) and 487 eyes (99.8%), respectively. Single-operation anatomic success was achieved in 90 of 111 eyes (81.1%) with PPV alone compared with 345 of 374 eyes (92.2%) with SB+PPV (P = 0.0010). Scleral buckling plus PPV showed greater SOAS than PPV alone in phakic eyes (P Conclusions Scleral buckling plus PPV resulted in greater SOAS outcomes than PPV alone for primary RRD repair. Phakic eyes achieved greater surgical success with SB+PPV, whereas eyes with a PCIOL achieved similar results with both methods. Most retinal redetachments occurred within the initial postoperative 3-month period. Single-operation anatomic success was associated with statistically significant visual improvement.
A novel assay to isolate and quantify third-stage Dirofilaria immitis and Brugia malayi larvae emerging from individual Aedes aegypti.

Mosquitoes transmit filarial nematodes to both human and animal hosts, with worldwide health and economic consequences. Transmission to a vertebrate host requires that ingested microfilariae develop into infective third-stage larvae capable of emerging from the mosquito proboscis onto the skin of the host during blood-feeding. Determining the number of microfilariae that successfully develop to infective third-stage larvae in the mosquito host is key to understanding parasite transmission potential and to developing new strategies to block these worms in their vector. We developed a novel method to efficiently assess the number of infective third-stage filarial larvae that emerge from experimentally infected mosquitoes. Following infection, individual mosquitoes were placed in wells of a multi-well culture plate and warmed to 37 °C to stimulate parasite emergence. Aedes aegypti infected with Dirofilaria immitis were used to determine infection conditions and assay timing. The assay was also tested with Brugia malayi-infected Ae. aegypti. Approximately 30% of Ae. aegypti infected with D. immitis and 50% of those infected with B. malayi produced emerging third-stage larvae. Once D. immitis third-stage larvae emerged at 13 days post infection, the proportion of mosquitoes producing them and the number produced per mosquito remained stable until at least day 21. The prevalence and intensity of emerging third-stage B. malayi were similar on days 12–14 post infection. Increased uptake of D. immitis microfilariae increased the fitness cost to the mosquito but did not increase the number of emerging third-stage larvae. We provide a new assay with an associated set of infection conditions that will facilitate assessment of the filarial transmission potential of mosquito vectors and promote preparation of uniformly infectious third-stage larvae for functional assays. The ability to quantify infection outcome will facilitate analyses of molecular interactions between vectors and filariae, ultimately allowing for the establishment of novel methods to block disease transmission.
CRISPR-mediated multigene integration enables Shikimate pathway refactoring for enhanced 2-phenylethanol biosynthesis in Kluyveromyces marxianus

2-phenylethanol (2-PE) is a rose-scented flavor and fragrance compound that is used in food, beverages, and personal care products. Compatibility with gasoline also makes it a potential biofuel or fuel additive. A biochemical process converting glucose or other fermentable sugars to 2-PE can potentially provide a more sustainable and economical production route than current methods that use chemical synthesis and/or isolation from plant material. We work toward this goal by engineering the Shikimate and Ehrlich pathways in the stress-tolerant yeast Kluyveromyces marxianus. First, we develop a multigene integration tool that uses CRISPR-Cas9 induced breaks on the genome as a selection for the one-step integration of an insert that encodes one, two, or three gene expression cassettes. Integration of a 5-kbp insert containing three overexpression cassettes successfully occurs with an efficiency of 51 ± 9% at the ABZ1 locus and was used to create a library of K. marxianus CBS 6556 strains with refactored Shikimate pathway genes. The 33-factorial library includes all combinations of KmARO4, KmARO7, and KmPHA2, each driven by three different promoters that span a wide expression range. Analysis of the refactored pathway library reveals that high expression of the tyrosine-deregulated KmARO4K221L and native KmPHA2, with the medium expression of feedback insensitive KmARO7G141S, results in the highest increase in 2-PE biosynthesis, producing 684 ± 73 mg/L. Ehrlich pathway engineering by overexpression of KmARO10 and disruption of KmEAT1 further increases 2-PE production to 766 ± 6 mg/L. The best strain achieves 1943 ± 63 mg/L 2-PE after 120 h fed-batch operation in shake flask cultures. The CRISPR-mediated multigene integration system expands the genome-editing toolset for K. marxianus, a promising multi-stress tolerant host for the biosynthesis of 2-PE and other aromatic compounds derived from the Shikimate pathway.
Cytomegalovirus in pediatric inflammatory bowel disease patients with acute severe colitis.

Abstract Background The prevalence and significance of cytomegalovirus (CMV) colitis in pediatric acute severe colitis is unknown. The aim of this study was to determine the prevalence of CMV in colonic mucosa of children with acute severe refractory colitis and compare the clinical characteristics and outcomes of CMV positive and negative patients. Methods In a case-control study, colonic biopsy specimens from children with severe refractory colitis were tested for CMV, and matched with non-refractory IBD controls. We characterized CMV positive patients by assessing laboratory values, concurrent medications, and need for surgery as compared with CMV negative refractory colitis patients. Results Colonic biopsies from 96 patients were evaluated for CMV; 48 with severe refractory colitis, and 48 non-refractory controls. There was an increased prevalence of CMV in severe refractory colitis [7/48 (14.6%), P Conclusions There is an increased prevalence of CMV in colonic biopsies of pediatric patients with severe refractory colitis. Viral burden does not predict clinical outcomes or subsequent need for colectomy.
Teamwork and Leadership Under Fire at the Epicenter of the COVID-19 Epidemic in the Bronx

The first Covid-19 patient was admitted to Montefiore Medical Center (MMC) on March 10, 2020. Soon thereafter there was a rapid and exponential surge of Covid-19 admissions to MMC that could have resulted in catastrophic consequences if MMC had been overwhelmed, as happened in Europe. To adjust to this crisis our institution, under the inspiring leadership of Dr. Philip Ozuah, President and CEO of Montefiore Medicine, adopted an "all hands on deck" approach, mobilizing our entire workforce to expand our units to accommodate the growing number of patients being admitted. Given that the internal medicine (IM) and ICU units are part of the department of medicine (DOM), the DOM was at the center of this mobilization. The DOM is the largest department at MMC and mobilizing it required careful planning, seamless teamwork, and strong leadership. To achieve that goal, we applied a framework that we designate the "3C framework," denoting Coordination, Communication, and Collaboration. In this report we describe the many initiatives the Montefiore Einstein DOM implemented during the Covid-19 pandemic using the 3C framework. These included establishing the Medicine Covid-19 Taskforce to lead our efforts, starting a daily newsletter for up-to-date communications, rapidly expanding the ICU and IM units, converting most specialty inpatient consults to eConsults, coordinating research studies, and more. The goal of this report is to serve as a guide on how the 3C framework helped us organize, mobilize, and energize the department of medicine effectively and efficiently during this unprecedented crisis.
Introduction and Executive Summary

Antitrust institutions in the United States and around the world are at a crossroads. Until now, antitrust has been based upon the consumer welfare standard, which has served as the lodestar of modern antitrust for the past 40 years. The hallmark of modern antitrust enforcement has been a case-by-case approach, driven by economic analysis and an evaluation of conduct on the merits. Courts and competition agencies have generally rejected invitations to jettison this successful approach in favor of presumptions of illegality and other shortcuts. The reason is simple: Relying upon presumptions instead of evidence risks rendering unlawful business behavior that in fact benefits consumers. But there is increasingly talk of a revolution that would overthrow the antitrust regime in the United States and, indeed, around the world. The drumbeat for this revolution appears to be strong and growing, with a broad range of enthusiastic participants and followers, including legal academics and economists, public intellectuals, think tankers, prominent members of Congress, and some foreign competition authorities. The would-be revolution has already had some success—at least as measured by the increasing discussion in academia, the popular press, and social media, and having embedded some of its central ideas in the platforms of both major U.S. political parties. Signs of the gathering revolution can also be seen in the various reports on antitrust and the digital economy emanating from around the world, such as those of the Stigler Center at the University of Chicago, the Australian Competition and Consumer Commission, The United Kingdom’s Competition and Markets Authority, the European Commission’s Directorate-General for Competition, the House Judiciary Committee’s Subcommittee on Antitrust, Commercial, and Administrative Law, and other think tanks and governmental bodies. The more radical revolutionaries want an antitrust regime to address a myriad of perceived socio-political problems, including, but not limited to, income inequality, relative wage depression, and the concentration of political power. Some call for incorporating other forms of regulation—particularly regulation of data and privacy—into the antitrust laws and putting them in the hands of the antitrust regulators. Their revolutionary zeal is aimed generally at the digital economy and in particular at large tech firms. Their proposed “fixes” targeting the largest tech firms run the gamut from the reinvigoration of competition rulemaking at the Federal Trade Commission, to shifting the burden of proof from plaintiffs to defendants in antitrust litigation, to extending the reach of antitrust to content moderation decisions, to size-based presumptions akin to the antitrust approach of the 1960s, to creating a new agency with unlimited regulatory power. These proposals have been refined to the point that they are now ripe, in our view, for rigorous examination from an evidence-based perspective.
Look-back policies for two-stage, pull-type production/inventory systems

We consider a two-stage, pull-type production/inventory system with a known service mechanism at the first stage. Set-ups and start-ups are involved in the operation of the second stage. We develop a production control policy for the second stage, within the class of (R, r) continuous-review policies, that minimizes the long run average total cost. We use a semi-Markov decision model to obtain an optimal policy for the operation of the second stage. The structure of the optimal policy suggests the use of a suboptimal look-back policy that delays the set-up at the second stage if the buffer lacks sufficient raw material. The performance of the system and the average total cost under the suboptimal policy can be obtained approximately using a decomposition algorithm. We show examples justifying the use of this suboptimal policy.
Perfectionism and disordered eating cognitions with women of color: The moderating role of self-compassion

Abstract Extant research suggests perfectionism is a risk factor for developing disordered eating among women, and that self-compassion may mitigate risk factors in their associations with disordered eating pathology. However, less is known about these relations among women of color (WOC). The current study examined the moderating role of self-compassion in the relationship between perfectionism and disordered eating cognitions with a sample of WOC (N = 132). Results indicated that self-compassion moderated the relationship between perfectionism and disordered eating cognitions, such that the magnitude of the relationship is significantly weaker at higher levels of self-compassion compared to lower levels of self-compassion. Black women also reported higher levels of self-compassion and lower levels of disordered eating cognitions compared to other WOC. Limitations, implications, and future directions are discussed.
Characterization of laser powder bed fusion surfaces for heat transfer applications

Abstract Imperative to the adoption of additive manufacturing for heat transfer applications is the understanding of as-built surface texture. In this work we analyze surface height data to determine the effect of build angle. Surface data is analyzed using existing and novel techniques and results are interpreted with respect to potential impact on heat transfer efficiency. Results show that complexity in the scan strategy of the build leads to difficulties developing correlation to existing techniques. Particles are also segmented from the surface and analysis of position show relationship to surface build angle, which may create stagnation points that detriment heat transfer.
First reproductive signs of inbreeding depression in Southern California male mountain lions (Puma concolor).

Abstract Long-term studies of mountain lions (Puma concolor) in Southern California have documented persistent small population sizes and the lowest genetic variation of any mountain lion population, except for the Federally endangered mountain lion subspecies, the Florida panther (Puma concolor coryi). There is overwhelming molecular evidence supporting inbreeding and low genetic diversity in these Southern California populations but there is a lack of phenotypical evidence of inbreeding depression. The primary goal of this study was to assess male mountain lions, in Southern California, for teratospermia (>60% abnormal sperm production), one of the first signs of inbreeding depression in mountain lions that are associated with decreased reproduction and population decline. From December 2019 to December 2020, we surveyed mountain lions during live captures, after mortality events, and in images collected from camera traps in the following populations: Santa Monica Mountains, Santa Susana Mountains, Santa Ana Mountains, and the Eastern Peninsular Range. Mountain lions were sampled for known physical abnormalities associated with inbreeding depression such as teratospermia, cryptorchidism, and distal tail kinks. For teratospermia, we extracted testes from five males post-mortem to assess sperm morphology. Epididymal sperm evaluations revealed all males were teratospermic. Across all samples, on average, 93% of observed spermatozoa were abnormal. We physically examined 32 mountain lions (males and females) for distal tail kinks, and we observed one individual affected. We examined 15 male mountain lions for cryptorchidism, and we observed one unilaterally cryptorchid male and one male with testes that differed significantly in size, likely reflecting asynchronous migration of the testes during puberty. Further, we identified three other animals in camera-trap images that had distal tail kinks, for a total of four. In conclusion, from December 2019 to December 2020, we identified nine individuals exhibiting physical signs of inbreeding depression. These reproductive and physical signs of inbreeding depression in Southern California mountain lions increase the urgency of conservation efforts in the region.
Prior austenite grain size and tempering effects on the dislocation density of low-C Nb–Ti microalloyed lath martensite

Abstract The dislocation density of two as-quenched and quenched and tempered low-C Nb–Ti microalloyed martensitic steels was measured with X-ray diffraction for a range of prior austenite grain sizes. The dislocation density decreases with increasing prior austenite grain size in the as-quenched condition but the opposite occurs after high temperature tempering. The flow strength of all conditions is a function of dislocation density and follows a Taylor hardening model. The properties are insensitive to Nb microalloying for the two alloys assessed.
Review and application of functional data analysis to chemical data—The example of the comparison, classification, and database search of forensic ink chromatograms

Abstract Functional data analysis is a relatively recent statistical method that can be applied to any dataset that can be thought of as a function. Functional data analysis considers functions as random elements. Modern chromatographic or spectroscopic techniques typically record analytical outputs as a function of time or wavelength. The purpose of this paper is to investigate the potential of functional data analysis for the characterization, comparison, and classification of chemical data. Forensic examination of ink is used as the main example in this paper as it covers different aspects of functional data analysis: (a) thin-layer chromatograms resulting from analysis of ink samples are characterized as functions of time and wavelength; (b) multiple samples analyzed at different times, or by different analysts, are registered into a common space; (c) a dimension reduction technique is applied to the sample functions to enable (d) their use for comparing between ink samples and for clustering large databases of inks. Our algorithms showed excellent performance and can readily be implemented to search and retrieve chemical profiles in large databases. From a theoretical standpoint, functional data analysis allows for a natural extension of multivariate analysis to datasets that can be thought of as functions. Algorithmically, functional data analysis proves to be a powerful technique that enables to detect functions minima and maxima, register multiple functions to a common space, and control the dimensionality and smoothness of a functional dataset. Nevertheless, we found that the implementation of functional data analysis is computationally complex when compared to classic multivariate analysis.
Cleaning methods for the isotopic determination of diatombound nitrogen in non‐fossil diatom frustules

Ground-truthing the stable isotope ratio of diatom frustule-bound organic nitrogen (N) as a paleoceanographic proxy of phytoplankton nutrient consumption calls for studies of modern diatoms from cultures and the field. This work has been hindered by the lack of a method to prepare fresh diatom material, which has significant geochemical differences from sedimentary fossil diatom, for analysis. We tested and compared the performance of five oxidative treatment protocols in cleaning fresh diatom frustules of external organic material for isotopic analysis of diatom frustule-bound N. We applied each treatment to diatom material from a T. weiss-flogii culture and measured the diatom-bound N content and isotopic composition (δ15N) of samples. A favored treatment is described that includes a multi-step, progressive, oxidative cleaning. The results suggest that the application of H2O2 to fresh biogenic opal for more than 20 min increased the accessibility of the N within the opal matrix to subsequent chemical treatment, an effect not observed for diatom frustules from deep ocean sediments. We attribute this effect to structural alteration and dissolution of the diatom opal by the H2O2, consistent with previous observations regarding the high reactivity of fresh diatom opal and its subsequent chemical hardening in the sedimentary environment. In addition, the presence of high levels of organic matter upon treatment with H2O2 may exacerbate the chemical alteration of frustules. We find that the δ15N of diatom-bound N is ~3 ‰ higher than that of the bulk culture biomass, consistent with expectations from surface sediment and down-core measurements.
Harvesting information to sustain our forests: serendipity supplement (2001) REU supplement (2001) deployment supplement (2003)

The goal of this project is to build an application-specific digital library to support the natural resource manager by providing access to project and agency documents such as Environmental Impact Statements and wildlife biologist specialist reports. As a domain-specific digital library, we have focused on the use of keywords, organized into controlled vocabularies, which are appropriate for this domain. This includes support for the use of place names because location is very important in describing documents and in making decisions.
Dominant-mode propagation characteristics for dielectric tape lines

Summary form only given, as follows. For some years the dielectric waveguide (and dielectric image line) have been studied at millimeter wavelengths, particularly for possible application in integrated circuits. Early analysis and measurements showed that low attenuation can be obtained, but that there may be a trade-off between reasonable field extent and low attenuation. This led to studies of various cross-sections for the dielectric, as well as choice of material (dielectric constant and loss tangent). It was found that the dielectric waveguide having the cross-section of a thin ellipse (i.e., like a tape) or a half ellipse mounted on an image plane provided lowest attenuation and certain other advantages, such as useful single mode bandwidth. This presentation will discuss quantitatively the comparisons for different dielectric constants, loss tangents, and ellipticities and compare attenuation factors, bandwidths, modal properties, and relative field extent. Measured results will be given for several millimeter wavelengths between 35 GHz and 140 GHz.
Stars in the Making

The observation of stars close to the galactic center requires a rethink of the star formation process.
Nanosecond pulsed electric fields mimic natural cell signal transduction mechanisms

Applications of nanosecond pulsed electric fields (nsPEF) to human cells and mammalian tissues indicate that, as the pulse durations and/or the electric field intensities decrease, effects on the plasma membrane decrease and effects in intracellular signal transduction mechanisms increase. NsPEFs that are below the threshold for electroporation-like effects on the plasma membrane mimic cell-signaling mechanisms that determine cell fate, depending on the nsPEF conditions and the cell type. At relatively high electric fields, cell-signaling mechanisms are activated to induce death by apoptosis in cells and tumors. At electric fields below the threshold for apoptosis, nsPEFs induce calcium release from intracellular stores that mimic physiologic ligand effects on IP3-dependent calcium channels in the endoplasmic reticulum and subsequent capacitative calcium influx activated by store operated calcium channels (SOCC) in plasma membranes. In human platelets, nsPEF-induced calcium mobilization mimics thrombin-induced platelet activation and aggregation, a natural mechanism to clot blood and heal wounds. Thus, nsPEFs recruit intracellular signaling mechanisms, providing a new technology to modulate cell function for potential therapeutic and/or diagnostic applications in the future
Some regularity theorems for operators in an enveloping algebra

The regularity properties of linear elliptic differential operators, acting on various function spaces, have been intensively studied in recent years (cf. [2]). In this paper, we consider the corresponding problem for an elliptic operator L in the enveloping algebra of a real Lie algebra r~, acting in a Hilbert space X(V) via the differential &r of a unitary representation r of the Lie group G. This problem was first studied by Nelson and Stinespring [16]. Later Langlands [14] extended their results to include representations on Banach spaces. In both cases the operator h-(L) and its adjoint were studied primarily via the action of the right invariant differential operatorL on the representative functions on G, using the standard elliptic regularity theory. Although this method was sufficient, e.g., to show that h(L) is essentially self-adjoint provided L is elliptic and symmetric (in the case of unitary rr), it did not give the precise domain of the adjoint of i%-(L). This additional information is very useful in the application of elliptic operators, e.g., to constructing analytic vectors for a representation, and in establishing regularity properties for the eigenfunction expansion associated with h(L)* (in case of symmetric L and unitary n). In this paper we establish some domain results for a restricted class of elliptic operators in the enveloping algebra of 0, relative to a unitary representation V. Iiamely, if 1, is of order 2m and is associated with a Hermitian elliptic form (see Section 2 for definition), then the Hilbert-space adjoint of h(L) has as domain the space .%‘zm(~) of 2m-times differentiable vectors for 7r. The proof of this result involves two developments. The first (Section 1) consists of establishing regularity properties for the action of R on the chain
Stereoselective action of acylated crude papain toward mandelic and atrolactic hydrazides

Abstract Acylated crude papain has been shown to exert stereoselective behavior toward racemic hydrazides devoid of an amino acid residue, namely, ( RS )-mandelic and ( RS )-atrolactic hydrazides. These hydrazides functioned as nucleophiles to yield N 1 , N 2 -diacylhydrazines. Several achiral acylating agents for the enzyme were chosen, including Z -glycine, BOC-glycine, AOC-glycine, and hippuric acid. With the exception of hippuric acid as the acylating agent, the reaction product, in every instance for these achiral hydrazides, consisted of an excess of the (+)- N 1 , N 2 -diacylhydrazine. The relative rates of product formation for the mandelic hydrazides were considerably greater than for corresponding reactions with racemic atrolactic hydrazide. When chiral Z - l -alanine was employed to acylate crude papain, the stereoselective action was most pronounced, with the formation of a mixture of diastereoisomers consisting of 73% N 1 -( Z - l -alanyl)- N 2 -[( R )-mandelyl]hydrazine. The relative reactivities for the electrophiles was Z - l -alanine ⋙ Z -glycine ⋍ hippuric acid ⪢ AOC-glycine > BOC-glycine. The hydrazides of ( R )-, ( S )-mandelic, and ( RS )-atrolactic acids were prepared by conversion of the corresponding acids to their esters by means of a catalytic dehydrating agent and subsequent treatment with a methanolic solution of hydrazine.
Bio-physical oceanographic interactions at the edge of the Arctic ice pack

Abstract About 7% of the world ocean is subject to the seasonal advance and retreat of sea ice. Physical processes at ice edges, interacting with biological phenomena, have been observed to promote phytoplankton blooms in both the Arctic (e.g., Bering and Greenland Seas) and the Antarctic. This interaction occurs primarily in spring with the retreating and melting sea ice laying down low-salinity derived stratification that reduces mixing in the photic zone which encourages a phytoplankton bloom. However other physical processes, such as oceanic eddys and fronts also play a role in enhancing primary productivity at the ice edge. This paper reviews biophysical oceanographic and meteorological interactions observed in both the eastern (Greenland Sea) and western (Bering Sea) Arctic. Comparisons of the physical and biological characteristics for these areas, as well as additional comparisons with the Barents Sea and Antarctic waters and other regions of the world ocean are presented. An estimate of some outstanding marginal ice edge research problems is also included.
Current prospects for the permeable base transistor

Abstract The permeable base transistor (PBT) is a new device which is predicted to operate at higher frequencies than any other three-terminal device. In addition to its applications for microwave amplification, the PBT may be useful in very high speed, digital logic circuits. The very small dimensions of the base structure and the requirement for embedding the base metallization in a semiconductor have necessitated the development of a great deal of new technology over the past six years. The greatest effort on the GaAs device has been to achieve controlled impurity levels and low defect densities in the epitaxial process used to embed the metal. A number of different embedding techniques have been used and extensively analyzed using secondary ion mass spectrometry (SIMS). The best device result achieved with the GaAs PBT is an extrapolated maximum frequency of oscillation (fmax) exceeding 100 GHz, and that achieved with a silicon PBT is an fmax of 30 GHz. Both of these results are comparable with the best results obtained with any high-frequency transistor.
Indirect measurement of 14N quadrupolar coupling for NH3 intercalated in potassium graphite

A method for indirect measurement of the nuclear quadrupolar coupling was developed and applied to NH3 molecules in the graphite intercalation compound K(NH3)4.3C24, which has a layered structure with alternating carbon and intercalant layers. Three triplets were observed in the H-1 NMR spectra of the compound. The value of the N-14 quadrupolar coupling constant of NH3 (3.7 MHz), determined indirectly from the H-1 NMR spectra, was intermediate between the gas value of 4.1 MHz and the solid-state value of 3.2 MHz. The method was also used to deduce the (H-1)-(H-1) and (N-14)-(H-1) dipolar interactions, the H-1 chemical shifts, and the molecular orientations and motions of NH3.
Metoclopramide Reversal of Decreased Gastrointestinal Myoelectric and Contractile Activity in a Model of Canine Postoperative Ileus

Postoperative ileus is characterized by decreased gastrointestinal myoelectric activity and motility. Metoclopramide was used to treat experimentally induced postoperative ileus in six dogs. Contractile activity was monitored by extraluminal strain gages on the pyloric antrum and proximal segment of the duodenum, and myoelectric activity was measured by recording bipolar electromyograms (EMGs) at the pyloric antrum, pyloric canal, proximal segment of the duodenum, proximal and distal parts of the jejunum, and ileum. Measurements were obtained from animals without ileus (baseline) and those with ileus that were either untreated or treated with metoclopramide. Adynamic ileus was induced by rubbing a 50 cm segment of jejunum with a dry sponge for 5 minutes and exposing the bowel to the air for 30 minutes. Treated dogs received metoclopramide (0.4 mg/kg 4 times daily [QID] intravenously [IV]), whereas untreated dogs received a saline placebo, starting 1 hour after celiotomy closure. Recordings were made for 26 hours after induction of ileus. The phases of the migrating myoelectric complex (MMC) were identified and motility index values were determined. During ileus, the MMC phase II duration was increased at the duodenum and phase III duration was decreased at the antrum, pylorus, duodenum, and proximal segment of the jejunum (p less than 0.05). Motility index values were decreased at the antrum and duodenum during ileus (p less than 0.05). Treatment with metoclopramide reversed the MMC phase III inhibition at the antrum and pylorus, and partially reversed the inhibition at the duodenum and jejunum (p less than 0.05). Motility index values were restored to preoperative baseline values with metoclopramide treatment (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
China's Exchange Rate Controversy: A Balanced Analysis

A noted American authority on China's economy and monetary policy presents a statistical as well as theoretical analysis of a variety of perspectives on the controversy surrounding China's currency, basing his paper on both. The author provides the historical background and comprehensive summaries, focusing on different viewpoints about whether China's currency is undervalued, and thus may contribute to global imbalances. In the paper, he divides observers involved in the controversy into two main camps, namely the ones who find China's trade balances to be sensitive to price effects through exchange rate adjustments and those who emphasize other factors as bearing the responsibility for China's large surpluses, including the U.S. credit bubble emerging before the global financial crisis, as well as a version of Dutch disease.
The influence of frequency across the time course of morphological processing: Evidence from the transposed-letter effect

The role that morphology plays in lexical access has been the subject of much debate, as has the influence of word frequency on morphological processing. The effect of frequency on morphological processing across the time course of lexical access was investigated using the transposed-letter effect. The results of two experiments (one masked-priming experiment and one eye-tracking experiment) outline a process in which morphological structure can be detected quickly and independently of frequency. The present study is also the first to show that transpositions that cross morpheme boundaries can be as disruptive as letter substitutions in inflected words, replicating earlier results with derived and compound words.
Viscous potential flow

Potential flows u = ⊇Φ are solutions of the Navier-Stokes equations for viscous incompressible fluids for which the vorticity is identically zero. The viscous term μ⊇ 2 u = μ⊇⊇ 2 Φ vanishes, but the viscous contribution to the stress in an incompressible fluid does not vanish in general. Here, we show how the viscosity of a viscous fluid in potential flow away from the boundary layers enters Prandtl's boundary layer equations. Potential flow equations for viscous compressible fluids are derived for sound waves which perturb the Navier-Stokes equations linearized on a state of rest. These linearized equations support a potential flow with the novel features that the Bernoulli equation and the potential as well as the stress depend on the viscosity. The effect of viscosity is to produce decay in time of spatially periodic waves or decay and growth in space of time-periodic waves. In all cases in which potential flows satisfy the Navier-Stokes equations, which includes all potential flows of incompressible fluids as well as potential flows in the acoustic approximation derived here, it is neither necessary nor useful to put the viscosity to zero
Mass transport and crystal growth of cadmium telluride by PVT

Systematic mass transport rate studies of CdTe in closed ampoules demonstrate the influence of source material synthesis and pretreatment on the physical vapor transport properties of this material. Minute deviations from the nominal stoichiometric composition of CdTe reduce the mass flux by several orders of magnitude. These observations could explain the large discrepancies in vapor transport and crystal growth rates of CdTe reported in the literature. Crystal growth experiments show that the unseeded vapor growth of CdTe by this technique yields crystal boules with large single crystalline grains. The results of x-ray diffraction and of chemical etching studies reveal that the single crystallinity of the grains is comparable to that of CdTe grown by other techniques. The combined results are promising for the further refinement of the vapor transport and crystal growth of CdTe.
Effects of induced convection upon the rate of crystallization

The effects of convection induced both by diffusion and by the density difference between the solid crystal and the adjacent liquid upon the rate of crystallization are examined in the absence of body forces. Both isothermal and non-isothermal crystallization are considered. When crystallization is taking place in a concentrated solution, significant errors can occur if induced convection is ignored. While diffusion-induced convection can be neglected for sufficiently dilute solutions, ignoring density differences even in this limit can lead to erroneous results.
RBC folic acid levels and cognitive performance in elderly patients: a preliminary report.

The human brain contains large concentrations of folic acid (FA) (Reynolds 1976), and deficiencies of this vitamin may be associated with both neurological (Reynolds 1976; Shorvon et al. 1980) and psychiatric disorders (Camey 1979; Botez et al. 1982; Abou-Saleh and Coppen 1986). Furthermore, when severe enough to be associated with meg~ob~astic anemia, FA deficiency may also result in reversible dementia (Botez et al. 1982; Lishman 1978). The biochemical role of FA in cognitive function is unclear, but it is known that the vitamin is important in the synthesis of norepinephrine (NE), dopamine (DA), and serotonin (5HT) (Turner 1979). Specifically, FA may be required for tyrosine hydroxylase to act in the rate-limiting step of DA and NE synthesis (Turner 1979). A deficiency of FA in rats has also been associated with a decrease in brain 5-HT levels, implying a role for FA in the synthesis or metabolism of this monoamine as well (Botez et al. 1979). DA, NE, and 5-HT are all thought to be important modulators of attentional and higher order memory functions (Woikowitz et