cssi/SciSciGPT-SciSciNet huggingface dataset:
Generation of animal form by the Chordin/Tolloid/BMP gradient: 100 years after D'Arcy Thompson.

The classic book “On Growth and Form” by naturalist D'Arcy Thompson was published 100 years ago. To celebrate this landmark, we present experiments in the Xenopus embryo that provide a framework for understanding how simple, quantitative transformations of a morphogen gradient might have affected evolution and morphological diversity of organisms. D'Arcy Thompson proposed that different morphologies might be generated by modifying physical parameters in an underlying system of Cartesian coordinates that pre-existed in Nature and arose during evolutionary history. Chordin is a BMP antagonist secreted by the Spemann organizer located on the dorsal side of the gastrula. Chordin generates a morphogen gradient as first proposed by mathematician Alan Turing. The rate-limiting step of this dorsal–ventral (D-V) morphogen is the degradation of Chordin by the Tolloid metalloproteinase in the ventral side. Chordin is expressed at gastrula on the dorsal side where BMP signaling is low, while at the opposite side peak levels of BMP signaling are reached. In fishes, amphibians, reptiles and birds, high BMP signaling in the ventral region induces transcription of a secreted inhibitor of Tolloid called Sizzled. By depleting Sizzled exclusively in the ventral half of the embryo we were able to expand the ventro-posterior region in an otherwise normal embryo. Conversely, ventral depletion of Tolloid, which stabilizes Chordin, decreased ventral and tail structures, phenocopying the tolloid zebrafish mutation. We explain how historical constraints recorded in the language of DNA become subject to the universal laws of physics when an ancestral reaction-diffusion morphogen gradient dictates form.
GCaMP expression in retinal ganglion cells characterized using a low-cost fundus imaging system.

Objective. Virus-transduced, intracellular-calcium indicators are effective reporters of neural activity, offering the advantage of cell-specific labeling. Due to the existence of an optimal time window for the expression of calcium indicators, a suitable tool for tracking GECI expression in vivo following transduction is highly desirable. Approach. We developed a noninvasive imaging approach based on a custom-modified, low-cost fundus viewing system that allowed us to monitor and characterize in vivo bright-field and fluorescence images of the mouse retina. AAV2-CAG-GCaMP6f was injected into a mouse eye. The fundus imaging system was used to measure fluorescence at several time points post injection. At defined time points, we prepared wholemount retina mounted on a transparent multielectrode array and used calcium imaging to evaluate the responsiveness of retinal ganglion cells (RGCs) to external electrical stimulation. Main results. The noninvasive fundus imaging system clearly resolves individual (RGCs and axons. RGC fluorescence intensity and the number of observable fluorescent cells show a similar rising trend from week 1 to week 3 after viral injection, indicating a consistent increase of GCaMP6f expression. Analysis of the in vivo fluorescence intensity trend and in vitro neurophysiological responsiveness shows that the slope of intensity versus days post injection can be used to estimate the optimal time for calcium imaging of RGCs in response to external electrical stimulation. Significance. The proposed fundus imaging system enables high-resolution digital fundus imaging in the mouse eye, based on off-the-shelf components. The long-term tracking experiment with in vitro calcium imaging validation demonstrates the system can serve as a powerful tool monitoring the level of genetically-encoded calcium indicator expression, further determining the optimal time window for following experiment.
The PNPLA3 I148M variant is associated with transaminase elevations in type 2 diabetes patients treated with basal insulin peglispro

Basal insulin peglispro (BIL) is a novel insulin with hepato-preferential action. In phase 3 trials, BIL showed significantly improved glycemic control but higher levels of transaminases (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)), triglycerides (TGs) and liver fat content (LFC) compared with insulin glargine (GL). As variants in PNPLA3 (I148M) and TM6SF2 (E167K) are associated with nonalcoholic fatty liver disease, we assessed these variants in type 2 diabetes (T2D) patients randomized to receive BIL (n=1822) or GL (n=1270) in three phase 3 trials. Magnetic resonance imaging assessments of LFC were conducted in a subset of patients (n=296). Analyses showed α-corrected significant increases in change from baseline in AST (P=0.0004) and nominal increases in ALT (P=0.019), and LFC (P=0.035) for PNPLA3 (148M/M) genotypes in the BIL arm at 26 weeks but no significant associations in GL. PNPLA3 (148M/M) was also associated with increases in total cholesterol (P=0.014) and low-density lipoprotein cholesterol (P=0.005) but not with hemoglobin A1c or TG. T2D patients with the PNPLA3 (148M/M) genotype treated with BIL may be more susceptible to increased liver fat deposition. The current data provide further insights into the biological role of PNPLA3 in lipid metabolism.
The Syrian conflict and public opinion among Syrians in Lebanon

Whom do ordinary Syrians support in their civil war? After decades of repression, the Syrian uprising unleashed an outpouring of political expression. Yet the study of Syrian public opinion is in i...
Recent Advances in InSAR Image Processing and Analysis

InSAR is a spaceborne mapping tool capable of remotely sensing small changes in land surface elevation at unprecedented spatial resolution. As discussed in previous chapters, InSAR utilizes two or more coherent phase signals acquired at different times from the same area to map ground deformation that may have occurred during the intervening period. In this chapter we describe advanced multi-temporal InSAR techniques for phase-coherent point identification, atmospheric artifact reduction, orbital error correction, and handling of phase ambiguity.
Interpretation of Freeze-Fracture Replicas of Insect Nervous Tissue

Freeze-fracture (FF) replication is an important method for visualizing, at high resolution and in three dimensions, ultrastructural topography of membranes and organelles in hydrated cells without the intervention of embedding media and with little or no chemical fixation. The tissue replicas provide extensive vistas of cleaved membranes. This remarkable technique, which splits unit membranes, also permits resolution of macromolecular architecture of biological membranes particularly with reference to the location of membrane proteins. When correlated with thin section EM, FF confirms and greatly extends our knowledge of specialized intercellular contacts. Observations of the latter provide essential data for cell biology: intercellular adhesion, low resistance metabolic and electronic coupling, chemical transmission and paracellular occluding barriers. The FF technique has also proved invaluable for understanding the nature and location of electrical and chemical junctions.
Potts Shunt Improves Right Ventricular Function and Coupling With Pulmonary Circulation in Children With Suprasystemic Pulmonary Arterial Hypertension.

Background: Pulmonary arterial hypertension is a progressive disease with poor outcomes in children. Right ventricular (RV) function is the most important determinant of the prognosis. Novel applic...
On a Simple Identity for the Conditional Expectation of Orthogonal Polynomials

Consider a two-dimensional random vector (X, Y )T. Let Q0, Q1,… denote orthogonal polynomials with respect to the marginal distribution of X and let P0, P1,… denote orthogonal polynomials with respect to the marginal distribution of Y. In this paper, identities of the form E[Pn(Y )|X] = anQn(X), for constants a0, a1,… are considered and necessary and sufficient conditions for this type of identity to hold are given,. The application of the identity to the maximal correlation of two random variables and to the L2 completeness of a bivariate distribution are discussed.
Institutional and Conceptual Barriers to Climate Change Adaptation for Coastal Cultural Heritage

Climate change is increasing the speed at which tangible coastal cultural heritage is changing in character or being lost through weathering, erosion, and inundation. Damages to coastal archeologic...
School counselor perceptions of the geosciences and career exploration activities used in their schools

A sample of 43 Mississippi school counselors was surveyed regarding resources they use in career counseling, as well as resources they believe are effective in informing students about STEM careers...
Road Map Generation and Feature Extraction from GPS Trajectories Data

Road maps are important in our personal lives and are widely used in many different applications. Therefore, an up-to-date road map is essential. The huge amount of GPS data collected from moving objects provides an opportunity to generate an up-to-date road map. In this paper, we propose a novel method to generate road maps using GPS trajectories that is accurate with good coverage area, has a minimum number of vertices and edges, and several details of the road network. Our algorithm starts by identifying the locations of intersections using a line simplification algorithm with spatial-constraints and grid-based method. Then, it creates graph connectivity information to connect intersections and build road segments. In addition, our algorithm extracts road features such as turn restrictions, average speed, road length, road type, and the number of cars traveling in a specific portion of the road. To demonstrate the accuracy of our proposed algorithm, we conduct experiments using two real data sets and compare our results with two baseline methods. The comparisons indicate that our algorithm is able to achieve higher F-score in terms of accuracy and generates a detailed road map that is not overly complex.
Evaluation of Light Reflectiveness of Modern Pavement: Standard Tungsten Incandescent and LED

AbstractThe objective of this research was to evaluate the reflectiveness of the two most commonly used modern pavement systems in the United States (concrete and asphalt). The R table used for roa...
High Resolution Signal Generation and Management in Fast Switching Power Electronic Systems

Advancements in power electronics necessitate new developments in technologies interfacing it correspondingly. Signal generation and measurement are among these peripheral technologies. Higher performance of new power devices have made higher switching frequencies and higher ratings of power converters realistic. These new opportunities require high-speed switching transients, which causes new settings at source and measurement ends. In this study, we have introduced a new figure of merit for high-speed signals, which are generated or measured. This figure of merit improves accuracy in comparisons and rigidizes specifications for signals. In addition, we studied high speed signal generation methods. Most methods cannot generate a signal with high figure of merit without increasing power consumption and area. We verified capability of a leading choice. The demonstrated signal is ultra-narrow with duty cycle less than 2%. Subsequently, high-speed signals need superior considerations for accurate measurement. Effects and solutions in accurate measurement of high horizontal resolution and high speed signals have been presented. Furthermore, considerations for noise in measurements is discussed.
Survey of Addiction Specialists' Use of Medications to Treat Alcohol Use Disorder.

Objectives: Several medications have been shown to be safe and effective for treating alcohol use disorder (AUD); however, these medications are prescribed infrequently. We conducted a survey of the demographics, practice characteristics, and self-perceived knowledge, experience, and opinions of addiction specialists on the use of AUD medications and how to increase their use. Methods: We sent a 19-question survey to members of the American Society of Addiction Medicine (ASAM) and the American Academy of Addiction Psychiatry (AAAP). Results: We received a total of 395 responses from ASAM members and 194 responses from AAAP members One hundred of the respondents were members of both organizations. The large majority of respondents (92.6%) were prescribers, and 81.6% were non-trainee physicians. The two most frequently used medications for treating AUD were oral naltrexone (27%) and long-acting naltrexone (18%). Respondents were significantly more confident in the strength of the research findings and evidence for the efficacy and safety of naltrexone than other AUD medications (p < 0.001). Respondents identified additional education to current providers about existing medications as the most important potential intervention to increase the use of AUD medications. Conclusions: Compared with a survey published in 2001, in 2018 the proportion of respondents who reported using naltrexone more than doubled and addiction specialists were more confident in their use of AUD medications, rating their efficacy and safety more highly. Consistent with findings from other recent studies, providing more education to practitioners about existing AUD medications may be the most effective way to increase their use.
Chapter 5 – Communication Knowledge

Publisher Summary This chapter describes techniques for communicating with students. Three types of graphic communication are used in intelligent tutors that include pedagogical agents, synthetic humans, and virtual reality. Synthetic humans are pedagogical AI agents rendered as realistic human characters. Humans already know how to engage in face-to-face conversation with people so synthetic humans enable them to communicate naturally without training. Natural language processing, 3D scenario simulation, emotion simulation, behavior modeling, and composite facial expression are often included in the implementation of synthetic humans. The virtual reality(VR) immerses students in a graphic environment that includes the pedagogical agent. When a virtual persona, or pedagogical graphic person, inhabits a teaching VR system along with the student, it enables collaboration and communication in ways that are impossible with traditional disembodied tutors. Virtual training materials typically incorporate simulated devices that respond to student actions using head or hand mounted tools. The potential of VR for supporting K-12 education is widely recognized. More than 40 pilot VR applications have been launched in grade schools, high schools, and colleges. One of the unique capabilities for this audience is to support visualization of abstract concepts, observation at atomic or planetary scales, and interaction with events that are otherwise unavailable because of issues of distance, time, or safety.
Psychological distress, coping behaviors, and preferences for support among New York healthcare workers during the COVID-19 pandemic.

Abstract Objective The mental health toll of COVID-19 on healthcare workers (HCW) is not yet fully described. We characterized distress, coping, and preferences for support among NYC HCWs during the COVID-19 pandemic. Methods This was a cross-sectional web survey of physicians, advanced practice providers, residents/fellows, and nurses, conducted during a peak of inpatient admissions for COVID-19 in NYC (April 9th–April 24th 2020) at a large medical center in NYC (n = 657). Results Positive screens for psychological symptoms were common; 57% for acute stress, 48% for depressive, and 33% for anxiety symptoms. For each, a higher percent of nurses/advanced practice providers screened positive vs. attending physicians, though housestaff's rates for acute stress and depression did not differ from either. Sixty-one percent of participants reported increased sense of meaning/purpose since the COVID-19 outbreak. Physical activity/exercise was the most common coping behavior (59%), and access to an individual therapist with online self-guided counseling (33%) garnered the most interest. Conclusions NYC HCWs, especially nurses and advanced practice providers, are experiencing COVID-19-related psychological distress. Participants reported using empirically-supported coping behaviors, and endorsed indicators of resilience, but they also reported interest in additional wellness resources. Programs developed to mitigate stress among HCWs during the COVID-19 pandemic should integrate HCW preferences.
Physical and Occupational Therapy Staffing Patterns in Nursing Homes and Their Association with Long-stay Resident Outcomes and Quality of Care

The purpose of this study is to examine Physical Therapy (PT) and Occupational Therapy (OT) staffing patterns in nursing homes and understand their relationship with quality performance. Bivariate analyses between PT/OT staffing and facility characteristics were performed to understand staffing patterns and random effects regressions were run to explore the link between therapy staff and quality. Findings suggest PT/OT staff have a positive influence on resident outcomes and therapy staffing patterns significantly differ across provider attributes, including size, profit status, and occupancy rate, among others. The findings can be used to inform policymakers about potential unintended consequences resulting from changes to Medicare reimbursement policies.
Spanish prepositions and silent PLACE

In this work I investigate the syntax and interpretation of two groups of spatial prepositions in Spanish: “small” Ps (e.g. bajo ‘under’) and “big” Ps (e.g. debajo ‘DE.under’). I show that small versus big Ps display a series of asymmetries, such as the (in)ability to take bare nominals and the (un)availability of coordination and adverb intervention. I propose that these contrasts can be derived under the hypothesis that small Ps select a single nominal complement, whereas big Ps select a more complex Possessor-Possessum structure, where the nominal occupies a specifier position, acting as the possessor of a silent PLACE element. Furthermore, I argue that unifying big Ps (but crucially not small Ps) with possessive structures accounts for the delimited versus non-delimited interpretation of these Ps.
Efficient electro-optical modulation on thin-film lithium niobate.

Thin-film lithium niobate has emerged as an excellent, multifaceted platform for integrated photonics and opto-electronics, in both classical and quantum domains. We introduce a novel, to the best of our knowledge, dual-capacitor electrode layout for an efficient interface between electrical and optical signals on this platform. It significantly enhances the electro-optical modulation efficiency to an exceptional voltage–length product of 0.64V⋅cm, thereby lowering the required electric power by many times. This technique can boost the performance of growing applications at the interface of integrated electronics and optics, such as microwave photonics, frequency comb generation, and telecommunication transmission.
Scaling of Joint Motion and Muscle Activation for 3-Dimensional Control of Reach Extent.

This study investigated the scaling of upper arm kinematics, joint motion, and muscle activation for three-dimensional (3D) reaches to targets of increasing distance. Fifteen participants completed...
Hume's 'A Treatise of Human Nature': An Introduction

Preface 1. The author and the book 2. First principles 3. Causation 4. Skepticism 5. Determinism 6. Passions, sympathy, and others' minds 7. Motivation: reason and the calm passions 8. Moral sense, reason, and moral skepticism 9. The foundations of morals Bibliography and further reading Index.
The Algorithm as Institution: Toward a Theoretical Framework for Automated Media Production and Consumption

Media scholars have only recently begun to recognize and investigate the importance of algorithms to a wide range of processes related to the production and consumption of media content. There have been few efforts thus far, though, to connect these developments to potentially relevant bodies of existing theory and research. This paper seeks to address this gap by exploring the utility of institutional theory as a potentially useful analytical framework for continued inquiry into the role of algorithms in the operation of media systems; and by offering some suggestions for ways in which an institutional analytical frame can be extended into algorithmic contexts.
Microbial Detection of Various Pollutants as an Early Warning System for Monitoring of Water Quality and Ecological Integrity of Natural Resources, in Russia

The author of this paper had long-term extensive experience working with water quality control and ecological integrity monitoring using microbial indices. This practice includes eight years of microbial bioassessments and the development of biocriteria implications for the detection of various organic pollutants, a number of heavy metals, and biological contamination in seawaters of Russia, which provided impressive results, demonstrating the advantages of such an approach for monitoring ecological integrity and water quality of estuaries and shallow and pelagic regions of marine coastal zones. The composition alteration of aquatic sediment or plankton microbial assemblages subjected to pollution resulted in an increase of pollutant-resistant (indicator) groups that detected expected and unexpected pollutants and their levels. The analysis of the proportion between all indicator groups assisted us in drawing conclusions about the natural or anthropogenic process or factors causing impairment of water resources. Keywords: ecological integrity monitoring; microbial indices; seawaters of Russia; microbial assemblages
Evaluation of Hume’s Principle

We are now in a position to make a survey of the principle of the priority of impressions to ideas: to examine both the nature of the principle and the use which Hume makes of it as a criterion of meaning. To do the latter task completely, we must give a full account of Hume’s theory of knowledge. We have to see, for example, given the principle, how successful is Hume’s treatment of the nature of space, time, abstract ideas, etc. However, we are concerned with Hume’s principle only in so far as it has direct bearing upon his treatment of demonstrative knowledge. In this part, we shall only touch upon some of the major difficulties inherent in Hume’s principle. A full evaluation of the principle will be given in the chapter following the detailed examination of Hume’s account of knowledge properly so called.
Gravitational time delay effects on cosmic microwave background anisotropies

We study the effect of gravitational time delay on the power spectra and bispectra of the cosmic microwave background (CMB) temperature and polarization anisotropies. The time delay effect modulates the spatial surface at recombination on which temperature anisotropies are observed, typically by $\ensuremath{\sim}1$ Mpc. While this is a relatively large shift, its observable effects in the temperature and polarization fields are suppressed by geometric considerations. The leading order effect is from its correlation with the closely related gravitational lensing effect. The change to the temperature-polarization cross power spectrum is of order $0.1%$ and is hence comparable to the cosmic variance for the power in the multipoles around $l\ensuremath{\sim}1000.$ While unlikely to be extracted from the data in its own right, its omission in modeling would produce a systematic error comparable to this limiting statistical error and, in principle, is relevant for future high precision experiments. Contributions to the bispectra result mainly from correlations with the Sachs-Wolfe effect and may safely be neglected in a low density universe.
Reproducibility of the NEI Scheimpflug Cataract Imaging System.

Purpose. The NEI Scheimpflug Cataract Imaging System was developed to allow for easy, accurate and reproducible image analysis of nuclear cataracts. This study was undertaken to determine the reproducibility of densitometric measurements of the lens nucleus using this modified system. Methods. Replicate Zeiss Scheimpflug images of the lenses in 143 eyes were obtained by one photographer. Normal and cataractous lenses (without central cortical or anterior subcapsular opacities) were sampled. Images were stored after testing for adequacy using immediate exposure checking. Densitometry of the nuclear region was then performed for each image. The interval within which 99% of the differences between repeat measurements may be expected to lie was used as a measure of reproducibility (99% range). Results. A 99% range of ±0.023 optical density units (odu) was obtained for nuclear densities < 0.30 odu (125 eyes). For lenses with nuclear densities ^ 0.30 odu (18 eyes), the 99% range was ±0.14 times the first measurement. Conclusion. This study shows the excellent reproducibility of this Scheimpflug imaging system in the nuclear region and demonstrates its usefulness in studies on nuclear cataracts, particularly for natural history studies and clinical trials of anti-cataract drugs. Invest Ophthalmol Vis Sci. 1994;35:3078-3084.
Risky Business: Popular Images and Reality of Capital Markets Handling Risk - From the Tulip Craze to the Decade of Greed

Speculators are often portrayed in literature, film and the media as evil businessmen who prey upon markets. Or they are portrayed as fools, who art with their money. The popular portraits accepted by the culture, while colorful, are ill-informed. This article looks at the view held of speculators in early bubbles such as Tulip Mania and the South Sea Bubble. It then moves to the 1780s and early 1790s in the United States and looks at the broadsides fired at speculators in Revolutionary War debt by supporters of Jefferson and Madison. Next, the Gilded Age exemplified by Jim Fisk (the great drummer and war profiteer), Daniel Drew (the Speculative Director), Jay Gould (the Dark Genius of Wall Street), and Commodore Vanderbilt ("the public be damned") is surveyed. The article concludes its survey with the Decade of Greed, the 1980s, as seen through "Other People's Money" and "Wall Street." While the portraits of these culprits are vivid and the fulminations and exhortations against speculation are entertaining, the historic and economic reality is much different. Speculators provide an important and discrete function. They provide capital and liquidity, risk taking, and rationing of resources vital for all market economies.
Pellicle effect on OPC modeling

As the patterning of IC manufacturing shrinks to the 32-nm node and beyond, high-NA and immersion lithography are required for pushing resolution to its physical limit. To achieve good OPC performance, various physical effects such as polarization, mask topography, and mask pellicle have to be considered to improve the model accuracy. The attenuation and the phase variation of TE and TM wave components induced by the pellicle would impact optical qualities in terms of resolution, distortion, defocus shift, and high-order aberrations. In this paper, the OPC model considering pellicle effects is investigated with Jones pupil. The CD variation induced by the pellicle effect can be predicted accurately. Therefore, the improvement on model accuracy for 32-nm node is demonstrated.
The interaction of electrodermal activity and expressed emotion in predicting symptoms in recent-onset schizophrenia

In the present study, expressed emotion (EE) was assessed among immediate family members of 94 recent-onset schizophrenia patients at initial study entry point, and patients' electrodermal activity (EDA) was measured without the presence of family members at a baseline outpatient stabilization assessment. Psychiatric symptoms were also rated, both at the baseline outpatient test, and at one-year follow-up. Electrodermal Activity × Expressed Emotion interactions were observed at both test points. In each case, the highest levels of negative symptoms were observed among those who exhibited greater EDA and occurred in a high-EE environment. These results support the view that the combination of high family EE and sympathetic nervous system arousal confer especially high risk for poor negative symptom outcomes.
Prognostic factors in sterile pancreatic necrosis

Although the overall mortality in sterile pancreatic necrosis is low, patients who experience systemic complications may have a higher mortality. To study the impact of systemic complications and other factors on survival, possible prognostic factors were evaluated among 26 patients who experienced at least one systemic complication. Mortality was 38%. Factors that correlated with a fatal outcome were high Ranson's scores during the first 48 hours (P = 0.01), high APACHE-II scores at admission (P = 0.04) and at 48 hours (P = 0.03), shock (P < 0.001), renal insufficiency (P < 0.05), multiple systemic complications (P < 0.001), and high body mass index (P = 0.01). Most systemic complications occurred during the first 2 weeks of illness. Logistic regression analysis showed that shock was the best predictor of a fatal outcome. Patients with favorable prognostic factors survived whether treated medically or surgically, whereas those with unfavorable factors had a fatal outcome whether treated medically or surgically. It is concluded that patients with severe sterile necrosis have a high mortality rate and that shock and other prognostic factors identify which patients are most likely to have a fatal outcome.
On the Nature and Etiology of Vascular Ectasias of the Colon: Degenerative lesions of aging

Vascular lesions of the right colon are being diagnosed increasingly as a cause of lower intestinal bleeding, but their nature and occurrence, primarily in the elderly, remains unexplained. Colons from patients with clinical and angiographic diagnoses of cecal vascular lesions were studied by injection and clearing, and by histological sections. In all injected specimens one or more mucosal vascular ectasias were identified. The mucosal lesions appeared to be secondary to dilated tortuous submucosal veins which were the more prominent feature and were often present without the mucosal ectasia. This suggests that ectasias are caused by chronic, intermittent, low grade obstruction to submucosal veins with dilation and tortuosity initially of submucosal veins, then of venules, capillaries, and arteries of the mucosal vascular unit. Ultimately, precapillary sphincters lose their competency, producing small arteriovenous communications. The concept that ectasias are degenerative lesions was evaluated by studying 15 right colons resected for carcinoma with no history of bleeding. Mucosal ectasias were identified in four colons and submucosal ectasias in eight. These investigations suggested that these lesions: (1) are vascular ectasias developing as a degenerative process of aging, (2) are present with or without bleeding in a significant portion of the population over 60 years of age, (3) are multiple more often than single, and (4) may represent the commonest cause of major lower intestinal bleeding in the elderly.
Thermal analytical investigation of biopolymers and humic- and carbonaceous-based soil and sediment organic matter.

Improved understanding of the physical, chemical, and thermodynamic properties of soil and sediment organic matter (SOM) is crucial in elucidating sorption mechanisms of hydrophobic organic compounds (HOCs) in soils and sediments. In this study, several thermoanalytical techniques, including thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), temperature-modulated differential scanning calorimetry (TMDSC), and thermal mechanical analysis (TMA) were applied to 13 different organic materials (three woods, two humic acids, three kerogens, and five black carbons) representing a spectrum of diagenetic and/or thermal histories. Second-order thermal transition temperatures (Tt) were identified in most materials, where the highest observed Tt values (typically characterized as glass transition temperatures (Tg)) were shown to closely relate to chemical characteristics of the organic samples as influenced by diagenetic or thermal alteration. Results further suggest a positive correlation b...
Narrowing the size distribution of the polymer acid improves PANI conductivity

By narrowing the size distribution of the polymer acid template, polyaniline (PANI) that is subsequently template synthesized exhibits enhanced conductivity. We used poly(2-acrylamido-2-methyl-1-propanesulfonic acid), PAAMPSA, as the polymer acid and it was synthesized by both conventional free-radical polymerization and atom transfer radical polymerization (ATRP). ATRP-derived PAAMPSA, or aPAAMPSA, has a narrower size distribution compared to conventional PAAMPSA at comparable molecular weights. In general, PANI–aPAAMPSA is two to three times as conductive as PANI–PAAMPSA. The enhanced conductivity of PANI–aPAAMPSA is strongly correlated with increases in the conjugation length and crystallinity of PANI. More surprisingly, PANI–aPAAMPSA adopts a crystal structure that is different from that of PANI–PAAMPSA, but one that is similar to that of PANI doped with a molecular acid counterpart of AAMPSA.
Integrated eight element Ku band transmit/receive beamformer chipset for low-cost commercial phased array antennas

An integrated eight element SiGe Ku band phased array and smart antenna beamformer chipset design is described. The beamformer chips include independent digital phase shifters and variable gain amplifiers in each of eight signal paths. The receive chip includes a low noise amplifier at each RF input, and the transmit chip includes a power amplifier at each RF output. Simulated performance meets design targets for the intended application to low-cost commercial phased array antennas for bidirectional satellite video and data ground terminals.
Microscopic Approach to Interfacial Structure in Ising-like Ferromagnets

The properties of an Ising-like ferromagnetic model are investigated in the presence of a space-dependent magnetic field which favors phase separation. The treatment is limited to very low temperatures where molecular-field theory seems to be applicable. The magnetization profile in the interface region is calculated, as well as the interface free energy, within an harmonic approximation to magnetization density modes in our model. The instability of the interface in the limit of vanishing external field, which was recently pointed out for fluid systems, is recovered and discussed in detail.
Sprouting and functional regeneration of an identified serotonergic neuron following axotomy.

An identified serotonergic neuron (C1) in the cerebral ganglion of Helisoma trivolvis sprouts following axotomy and rapidly (seven to eight days) regenerates to recover its regulation of feeding motor output from neurons of the buccal ganglia. The morphologies of normal and regenerated neurons C1 were compared. Intracellular injection of the fluorescent dye, Lucifer Yellow, into neuron C1 was compared with serotonin immunofluorescent staining of the cerebral and buccal ganglia. The two techniques revealed different and complimentary representations of the morphology of neuron C1. Lucifer Yellow provided optimal staining of the soma, major axon branches, and dendritic arborization. Immunocytochemical staining revealed terminal axon branches on distant targets and showed an extensive plexus of fine fibers in the sheaths of ganglia and nerve trunks. In addition to C1, serotonin-like immunoreactivity was localized in approximately 30 other neurons in each of the paired cerebral ganglia. Only cerebral neurons C1 had axons projecting to the buccal ganglia. No neuronal somata in the buccal ganglia displayed serotonin-like immunoreactivity. Observations of regenerating neurons C1 demonstrated: (1) Actively growing neurites, both in situ and in cell culture, displayed serotonin-like immunoreactivity; (2) severed distal axons of C1 retained serotonin-like immunoreactivity for up to 28 days; (3) axotomized neurons C1 regenerated to restore functional control over the feeding motor program.
FOUR GOALS FOR A STRONGER U.S. FINANCIAL SERVICES INDUSTRY (AND FIVE WAYS FOR CONGRESS TO HELP US GET THERE)

For at least the past 15 years, the preferred model for financial modernization among U.S. lawmakers and regulators has been based on the concept of the financial services holding company (FSHC) with functional regulation of its financial subsidiaries. Such an approach makes eminently good sense in a world where it is possible to make clear distinctions among different financial functions and between financial services and other information-based businesses. Although this may have been the case 15 years ago, today the FSHC model will not deal with financial convergence and the broader convergence of information-based businesses in a completely satisfactory way. To lay the groundwork for a financial structure that can carry us into the next century, Congress needs to look beyond the approaches it has been willing to consider to date. Instead of simply eliminating remaining entry barriers, it needs to permit true financial integration with a much simpler and more streamlined system of regulation than we have today. After holding up four goals for a financial services marketplace for the next century, this article offers five “sensible and politically realistic” suggestions for the 105th Congress that would help move the U.S. financial sector toward those goals.
Melatonin suppression by static and extremely low frequency electromagnetic fields: Relationship to the reported increased incidence of cancer

An increased cancer incidence has been reported in individuals living and/or working in an environment in which they are exposed to higher than normal artificial electromagnetic fields. One of the most uniform changes associated with the exposure of animals to either pulsed static geomagnetic fields or to sinusoidal extremely low frequency magnetic fields has been a reduction in high night-time levels of melatonin. Melatonin is a hormone produced especially at night in the pineal gland, a pea-sized organ near the center of the human brain. The high nocturnal production of melatonin leads to elevated blood melatonin levels at night as well. The exposure of humans or animals to light (visible electromagnetic radiation) at night rapidly depresses pineal melatonin production and blood melatonin levels. Likewise, the exposure of animals to various pulsed static and extremely low frequency magnetic fields also reduces melatonin levels. Melatonin is a potent oncostatic agent and it prevents both the initiation and promotion of cancer. Reduction of melatonin, at night, by any means, increases cells' vulnerability to alteration by carcinogenic agents. Thus, if in fact artificial electromagnetic field exposure increases the incidence of cancer in humans, a plausible mechanism could involve a reduction in melatonin which is the consequence of such exposures.
Effect of mechanical stress on the line width of single photon absorptions in Mn12-acetate

Abstract Quantum mechanical tunneling of the magnetic moment has been observed in several single-molecule magnets, including Mn 12 -acetate, but the tunneling mechanism is not entirely understood. It has been proposed that tunneling occurs due to defects in the crystal structure. These defects can be studied through their effect on the inhomogeneous line width of single photon (intrawell) transitions. However, most previous studies of the line width have been performed on crystals that have been pressed into pellets, which may introduce additional defects into the crystal structure. We report on measurements of the line width of loose crystals using the method of time-domain terahertz spectroscopy. The line width is not significantly reduced from the measurements on pressed pellets.
Malaria Parasites of the “Borriguerro'’Lizard, Ameiva ameiva (Sauria: Teiidae) in Panama*

SYNOPSIS. The teiid lizard Ameiva ameiva praesignis in Panama is parasitized by 2 species of Plasmodium: P. cnemidophori Carini and P. diminutivum sp. n. The Panamanian strain of P. cnemidophori has thick macrogametocytes which are larger than the oval microgametocytes, and schizonts which contain 42–119 nuclei. P. diminutivum is characterized by round to oval gametocytes which are usually smaller than the host cell nucleus; fan-shaped schizonts with 4–6 nuclei; and prominently vacuolated young stages, with a thick band of chromatin along the periphery of the vacuole.
Seismic properties of rocks from an exposure of extended continental crust—new laboratory measurements from the Ivrea Zone

Abstract Compressional wave velocities for new samples from the Ivrea-Verbano Zone (IVZ) and Strona-Ceneri Zone (SCZ) have been measured to 600 MPa in order to better understand the petrologic controls on velocity and to provide an expanded base for seismological models of the crust as represented by these terrains. These data, coupled with previous measurements, show that preferred orientation of mica controls both the velocity hysteresis with pressure and seismic anisotropy of SCZ and IVZ schists and gneisses. IVZ paragneisses form the basis of a linear velocity-density relationship for metagraywackes of various metamorphic grade. This relationship falls close to that expected for mafic rocks and overlaps velocity-density data for IVZ mafic gneisses. One-dimensional near-vertical reflection models, based on these data and recent structural reconstructions of the terrain, show that lower crustal reflectivity can be related to high reflection coefficients associated with interlayered sequences of upper amphibolite-granulite facies paragneiss, mafic gneiss and ultramafic rocks. Transparent upper crustal levels in the model result from the overall similarity of velocities for schists, gneisses and granites from the structurally and lithologically complex SCZ. A mean lower crustal velocity of 7.1 km/s is calculated for the part of the IVZ composed of interlayered mafic gneiss and paragneiss and for another area dominated by a mafic layered igneous complex. The velocity-density analysis coupled with this observation emphasize the ambiguity inherent in interpretation of crustal composition from P-wave velocity data in the absence of other constraints.
Where is social informatics

The term "social informatics," at least among those who work in one or more of the various fields it helps to unite, unavoidably elicits its originator and greatest advocate, Rob Kling. Kling coined the term in order to help describe a perspective in which information technologies were studied within their social contexts. It was also used to describe a new interdiscipline, one that drew computer science and the social sciences closer together, and that recognized a literature at this nexus as an emergent, cohesive whole. Kling answered the question "What is social informatics?" explicitly not only in widely read articles on the topic, but in public talks and private conversations. As the idea of social informatics has become more widely known, another question follows it: where is social informatics? Has it made an imprint on scholarly institutions?
Distinction between heavy metal and organic toxicity using EDTA chelation and microbial assays

Use of the EDTA chelation test in conjunction with microbioassays for general toxicity (Microtox) and heavy metal toxicity (β-galactosidase activity) allowed us to identify the presence of heavy metal toxicity, and to distinguish between cases in which toxicity was due solely to either heavy metals, organic compounds, or a mixture of these chemicals. The technique is effective over a wide range of water hardness and pH. Screening of industrial wastewater samples by the EDTA-microbioassay technique gave results that were consistent with chemical analysis of samples by atomic absorption. © 1992 John Wiley & sons, Inc.
Hydrodynamic models and correlations for bare and wire-wrapped hexagonal rod bundles — Bundle friction factors, subchannel friction factors and mixing parameters

Abstract Consistent hydrodynamic models for subchannel friction factors and mixing parameters in wire-wrapped rod bundles have been developed for use in subchannel analysis codes. Both flow regime and geometry effects are taken into account in these models. The laminar, transition and turbulent flow regimes are covered for the range of liquid metal fast breeder reactor (LMFBR) rod bundles of design interest. Correlations based on the models for the subchannel friction factor and mixing parameters are calibrated by the available world data. This data includes recent 37-pin hydrodynamic experiments with a geometry between that of typical fuel and blanket assembly design performed by the authors. Specific correlations are presented for subchannel and bundle friction factors, flow split, enhanced eddy diffusivity and the peripheral wire induced swirl velocity.
New and Unusual Bonding in Open Shell van der Waals Molecules Revealed by the Heavy Atom Effect: The Case of BAr

Calculations are reported for the excited 14Π and C2Δ electronic states of BAr and the (nominally 2s2p2) 4P and 2D states of atomic boron. It was found necessary to extend an augmented valence triple-zeta orbital basis set to correctly describe the C2Δ state. This enhancement is necessitated by the near degeneracy of the valence 2s2p2 2D and Rydberg 2s23d 2D electron configurations in atomic boron, both of which are required to describe BAr C2Δ. Unexpectedly strong bonding in the C2Δ state is found. This bonding is shown to have its root in a type of coordinate covalency, dative bonding, that is sensitive to electron correlation effects and is reflected in a large external heavy atom effect in the spin−orbit coupling of the 14Π and C2Δ states.
The International Code of Virus Classification and Nomenclature (ICVCN): proposal to delete Rule 3.41

It is proposed to delete Rule 3.41 of the International Code of Virus Classification and Nomenclature, which requires the name of a virus taxon to precede the term for the taxonomic unit.
Maternal coagulopathy after umbilical cord occlusion for twin reversed arterial perfusion sequence.

BACKGROUND Twin reversed arterial perfusion sequence is a rare complication of monochorionic twin gestations for which therapy involves the disruption of vascular anastomoses between the pump twin and acardiac twin and death of the acardius. CASE A 37-year-old woman, gravida 11 para 2, with a monochorionic twin pregnancy complicated by twin reversed arterial perfusion sequence who underwent umbilical cord occlusion at 24 weeks of gestation was admitted in preterm labor at 33 weeks of gestation. Maternal disseminated intravascular coagulation (DIC) was diagnosed and her labor was induced. She received multiple blood products to correct her coagulopathy and had an uncomplicated vaginal delivery of the viable pump twin. CONCLUSION Maternal DIC may complicate fetal death after umbilical cord occlusion.