cssi/SciSciGPT-SciSciNet huggingface dataset:
Particle Suspensions and their Regions of Effect in the Neuse River Estuary: Implications for Water Quality Monitoring

Monitoring of estuarine condition depends on water quality parameters that have significant and interpretable ecological effects and can be assessed either in situ or via rapid laboratory techniques. Two commonly measured parameters are water column turbidity (NTU) and total suspended solids (TSS). Under certain conditions, either of these measures could represent a proxy for runoff and provide rapid, in situ measures to improve protection of the public by decreasing the time required to detect and monitor associated effects (e.g., reduced water clarity and eutrophication). The Neuse River Estuary (NRE) has experienced a decline in water quality due to anthropogenic inputs, including stormwater containing nutrient and particle loads. Water samples were collected from the NRE during both dry weather and storm events over 16 mo across the entire estuarine gradient. Particle size distributions, ratio of particulate organic carbon to nitrogen, chlorophylla (chla), TSS, and NTU were measured in each of these samples, with the data separated into regions based on salinity and depth of sample collection. Particle analyses were directed at identifying suspensions dominated by phytoplankton, runoff particles, or resuspended sediments. Particle size distributions for suspensions in Region I (all samples with salinity less than 2) varied little during sampling, resulting in a robust NTU-TSS relationship. This relationship confirmed the usefulness of turbidity as a measure of runoff and resuspension of recently deposited runoff in the upper NRE. Phytoplankton cells represented a majority of the particles in Region II (surface samples with salinity greater than 2), based on the close relationship between chla and total particle volume in these samples. Suspensions of large, nearly uniform diameter particles, which are likely aggregates and resuspended sediment, were observed in Region III (bottom samples with salinity greater than 2). Using these techniques as part of routine monitoring, particle suspension measures in different hydrographic regions of an estuary provide evidence useful for identifying the source and water quality consequences of particle suspensions (e.g., microbial contamination and algal blooms).
The Mechanism of Vision: XV. Preliminary Studies of the Rat's Capacity for Detail Vision

(1938). The Mechanism of Vision: XV. Preliminary Studies of the Rat's Capacity for Detail Vision. The Journal of General Psychology: Vol. 18, No. 1, pp. 123-193.
Large Eddy Simulation of Flow and Heat Transfer in the Developing Flow Region of a Rotating Gas Turbine Blade Internal Cooling Duct With Coriolis and Buoyancy Forces

The problem of accurately predicting the flow and heat transfer in the ribbed internal cooling duct of a rotating gas turbine blade is addressed with the use of large eddy simulations (LES). Four calculations of the developing flow region of a rotating duct with ribs on opposite walls are used to study changes in the buoyancy parameter at a constant rotation rate. The Reynolds number is 20,000, the rotation number is 0.3, and the buoyancy parameter is varied between 0.00, 0.25, 0.45, and 0.65. Previous experimental studies have noted that leading wall heat transfer augmentation decreases as the buoyancy parameter increases with low buoyancy, but heat transfer then increases with high buoyancy. However, no consistent physical explanation has been given in the literature. The LES results from this study show that the initial decrease in augmentation with buoyancy is a result of larger separated regions at the leading wall. However, as the separated region spans the full pitch between ribs with an increase in buoyancy parameter, it leads to increased turbulence and increased entrainment of mainstream fluid, which is redirected toward the leading wall by the presence of a rib. The impinging mainstream fluid results in heat transfer augmentation in the region immediately upstream of a rib. The results obtained from this study are in very good agreement with previous experimental results.
Visualization of the extracellular matrix surrounding pycnidiospores, germlings, and appressoria of Phyllosticta ampelicida

The presence and extent of the extracellular matrix surrounding pycnidiospore germlings and appressoria of Phyllosticta ampelicida was assessed using cryo-scanning and light microscopy. Conidia of ...
The Operational Mesogamma-Scale Analysis and Forecast System of the U.S. Army Test and Evaluation Command. Part I: Overview of the Modeling System, the Forecast Products, and How the Products Are Used

Given the rapid increase in the use of operational mesoscale models to satisfy different specialized needs, it is important for the community to share ideas and solutions for meeting the many associated challenges that encompass science, technology, education, and training. As a contribution toward this objective, this paper begins a series that reports on the characteristics and performance of an operational mesogammascale weather analysis and forecasting system that has been developed for use by the U.S. Army Test and Evaluation Command. During the more than five years that this four-dimensional weather system has been in use at seven U.S. Army test ranges, valuable experience has been gained about the production and effective use of high-resolution model products for satisfying a variety of needs. This paper serves as a foundation for the rest of the papers in the series by describing the operational requirements for the system, the data assimilation and forecasting system characteristics, and the forecaster training that is required for the finescale products to be used effectively.
What are we teaching in cyber competitions

Student competitions are widespread across all academic disciplines, and are often touted as a means to motivate and educate students. Competitions may be internal within a single class or course, or vie school against school as regional, national, or international competitions and exist at all levels including 9–12 grades. These competitions have different formats and focuses such as vulnerability assessments, forensic challenges, offensive, and defensive competitions (or a combination of these). Some competitions require simple scripts and are considered ideal for script kitties while others require in-depth understanding of computer security and networking techniques to successfully compete in the competition. While the number of competitions and students participating in them have increased, it is unclear whether the stated academic goals of the competition are being met. In some cases, it appears that the focus of the student and institutional effort is more on the competition itself than on learning underlying concepts and developing skills. At our institution, students participate in several cyber-competitions, some of which we have initiated. The purpose of this paper is to survey existing cybercompetitions to understand the purpose of the competition, review underlying stated educational goals, and explore how the competition meets these goals. We compare the role of cyber competitions with the role of other computer-related competitions such as robotics, programming, unmanned aerial vehicles, and artificial intelligence comparing and contrasting the educational impact of the competitions on the participants.
Insect Neurosecretory Material Separated by Differential Centrifugation

The factor which accelerates the beating of the insect heart was found to be concentrated in a "large granule" fraction of the corpora cardiaca of the cockroach, Periplaneta americana (L.).
Hyaluronic acid in localized myxedema.

ABSTRACT The localized myxedema lesions of Graves' disease contained acid mucopolysaccharides which were 6–16 times the normal skin concentration, and which were composed almost completely, if not entirely, of hyaluronic acid. This observation contrasts with previous reports which have suggested that other mucopolysaccharide polymers were important constituents in this disorder. It is proposed that the manifestations of Graves' disease, other than those induced by hyperthyroidism, have a common biochemical disturbance resulting in increased tissue hyaluronic acid.
A stoichiometric model of bacterial growth

Abstract Numerous investigators have reported that the standard Monod model of bacterial growth does not adequately describe the transient response of activated sludge systems. By incorporating intracellular storage and extracellular release of shunted soluble carbon compounds in a model of bacterial growth and substrate utilization, a more accurate picture of the activated sludge process is obtained. The basic premise of the model developed in this paper is that a heterotrophic culture of bacteria will react with a carbonaceous substrate in the presence of oxygen and nutrients to produce more bacteria, carbon dioxide, water, various shunt products and storage products. The biomass is structured into three components: active biomass, stored biomass, and inert biomass. Three soluble components are considered: primary substrate, a secondary, shunted, biodegradable substrate and a shunted non-biodegradable substrate. Stoichiometric coefficients and rate forms have been proposed for the formation of each of these components and for the rate of oxygen utilization. The model is shown to be effective in simulating the step response to a recycle reactor, a batch test with a high initial substrate concentration and the step response of a chemostat.
William Cobbett: Champion of Freedom

The article concerns Cobbett's "A History of the Last Hundred Days of English Freedom" consistng of three letters.
Difficulties concerning a Finite Photon Rest Mass

Pecker, Roberts and Vigier have suggested that much, if not all, of the cosmological redshift might be attributable to inelastic photon–photon scattering—if the photon possesses a finite rest-mass1. Pecker and Vigier have attempted (private communication) to apply Vigier's ideas to the electromagnetic propagation anomalies observed by Sadeh and others2,3. We agree in part with the ideas of Vigier and his co-workers, but their hypothesis, as regards these phenomena, cannot be completely correct as stated.
The need for public policies to promote healthier food consumption: A comment on Wansink and Chandon (2014)

Abstract Current approaches to addressing obesity have fallen short. This is largely due to the many environmental forces that undermine people's self-regulatory capacity to be personally responsible for their food choices. Novel insights from the social sciences are needed to inform voluntary, health-promoting actions by companies, institutions, and citizens as well as the design of public health policies. Voluntary interventions that rely on nudges should complement traditional public health strategies such as taxation and restriction of child-targeted marketing in schools. In this commentary, we discuss four food policy issues that would benefit from consumer psychology research: (a) the restriction of food marketing to children, (b) provision of nutrition information through food labels, (c) improving school food environments, and (d) placing limits on portion sizes. Identifying effective solutions for obesity will require approaches that integrate psychological, public health, and legal perspectives and methods.
Evidence for VirB4-Mediated Dislocation of Membrane-Integrated VirB2 Pilin during Biogenesis of the Agrobacterium VirB/VirD4 Type IV Secretion System

Agrobacterium VirB2 pilin is required for assembly of the VirB/VirD4 type IV secretion system (T4SS). The propilin is processed by signal sequence cleavage and covalent linkage of the N and C termini, and the cyclized pilin integrates into the inner membrane (IM) as a pool for assembly of the secretion channel and T pilus. Here, by use of the substituted cysteine accessibility method (SCAM), we defined the VirB2 IM topology and then identified distinct contributions of the T4SS ATPase subunits to the pilin structural organization. Labeling patterns of Cys-substituted pilins exposed to the membrane-impermeative, thiol-reactive reagent 3-(N-maleimidopropionyl)biocytin (MPB) supported a topology model in which two hydrophobic stretches comprise transmembrane domains, an intervening hydrophilic loop (residues 90 to 94) is cytoplasmic, and the hydrophilic N and C termini joined at residues 48 and 121 form a periplasmic loop. Interestingly, the VirB4 ATPase, but not a Walker A nucleoside triphosphate (NTP) binding motif mutant, induced (i) MPB labeling of Cys94, a residue that in the absence of the ATPase is located in the cytoplasmic loop, and (ii) release of pilin from the IM upon osmotic shock. These findings, coupled with evidence for VirB2-VirB4 complex formation by coimmunoprecipitation, support a model in which VirB4 functions as a dislocation motor to extract pilins from the IM during T4SS biogenesis. The VirB11 ATPase functioned together with VirB4 to induce a structural change in the pilin that was detectable by MPB labeling, suggestive of a role for VirB11 as a modulator of VirB4 dislocase activity.
Interwell Tracer Analyses of a Hydraulically Fractured Granitic Geothermal Reservoir

Field experiments using fluorescent dye and radioactive tracers (Br{sup 82} and I{sup 131}) have been employed to characterize a hot, low-matrix permeability, hydraulically-fractured granitic reservoir at depths of 2440 to 2960 m (8000 to 9700 ft). Tracer profiles and residence time distributions have been used to delineate changes in the fracture system, particularly in diagnosing pathological flow patterns and in identifying new injection and production zones. The effectiveness of one- and two-dimensional theoretical dispersion models utilizing single and multiple porous, fractured zones with velocity and formation dependent effects are discussed with respect to actual field data.
Strategies to enhance rituximab anti-tumor activity in the treatment of CD20-positive B-cell neoplasms

Rituximab is a chimeric monoclonal anti-CD20 antibody and was the first monoclonal antibody (mAb) therapy approved by FDA (Food and Drug Administration) for the treatment of B-cell lymphoma. It has revolutionized the treatment of patients with CD20-positive non-Hodgkin’s lymphoma and CLL. Rituximab is currently being used in virtually all patients with B-cell lymphomas either alone or in combination with chemotherapy. Despite its excellent safety and efficacy profile, only a small portion of B-cell lymphoma patients treated with rituximab as a single agent have sustained complete remissions. Combining rituximab with standard chemotherapy regimens is associated with higher response rates, and improved survival in a subset of patients. Unfortunately, a significant percentage of patients who initially respond to rituximab eventually relapse, and there are patients that demonstrate intrinsic resistance to initial therapy. In the last decade, ongoing scientific research has led to a better understanding of rituximab-associated cytotoxic mechanisms against lymphoma target cells. Scientific efforts are increasingly being focused in developing new strategies to improve mAb activity. Various strategies include the following: combining rituximab with different biologic agents (e.g. cytokines, immunomodulatory drugs); developing novel antibody constructs (including bi-specific antibodies); and/or inhibiting signaling pathways associated with lymphomagenesis and immuno-chemotherapy resistance. In this review article, we will provide an overview of various rituximab-associated cytotoxic mechanisms and novel strategies to improve mAb activity against B-cell lymphoma.
Incidence of Cleft Lips, Palates Rising

Dr. Harold C. Slavkin explores the possible causes of a familiar birth defect in “Incidence of Cleft Lips, Palates Rising” . About 1:700 live human births are affected by cleft lip and palate. Socioeconomic factors—teenage pregnancies, pregnancies in women older than 35, increased consumption of teratogens during early months of pregnancy—have resulted in increased numbers of congenital malformations in the United States.
Community acquired influenza requiring hospitalization: vaccine status is unrelated to morbidity in children with cancer.

Background Community acquired influenza can be severe and there are few data regarding hospitalization for children with cancer and influenza. Association between prior vaccination and infection severity has not been studied, although vaccination is standard practice. Procedure Patients with malignancy or prior stem cell transplant (SCT) were identified using a database of children with laboratory confirmed influenza (2000–2005). Other data collected included receipt of vaccine, absolute neutrophil count (ANC) and absolute lymphocyte count (ALC). These were compared with intensive care unit (ICU) stay, respiratory complications and hospital days. Results There were 39 patients with laboratory-confirmed influenza with a median age of 6.9 years. Twenty-four (62%) were on cancer therapy at time of infection and 18 (46%) had received the influenza vaccination that season. Measures of immune status included ANC at time of infection (median 1,530 cells/µl; inter-quartile range, 315, 4347), presence of graft versus host disease 2 (5%) and steroid therapy 4 (10%) patients. All had a low ALC (median 448 cells/µl; IQR 189, 861). Respiratory complications occurred in 8 (20%), ICU admissions in 4 (10%) and death in 2 (5%) patients. Median hospital stay was 2 days. All ICU admissions occurred in unvaccinated patients (P = 0.1). Vaccine status, ANC ( 1,000) and ALC ( 500) were not associated with length of stay or respiratory complications. Conclusions Influenza infection can be severe in children with cancer and complications occur despite vaccination. Prospective evaluation of vaccine response is worthy of future study. Pediatr Blood Cancer 2010; 54:79–82. © 2009 Wiley-Liss, Inc.
Divergent elbow dislocation with radial shaft fracture, distal ulnar deformation, and distal radioulnar joint instability: an unclassifiable Monteggia variant

Originally described by Monteggia and later classified by Bado, elbow dislocations with concurrent radial and ulnar shaft fractures with distal radioulnar joint (DRUJ) disruption are considered operative cases with high-energy injurious etiologies. Here, we present an unclassifiable Monteggia variant fracture suffered through a high axial load mechanism in a 47-year-old female. The fracture pattern initially exhibited included a divergent elbow dislocation, a radial shaft fracture, plastic deformation of the distal ulna, and DRUJ instability. Here we describe the pattern in detail, along with definitive treatment and clinical outcome at 1 year follow-up.
Flow birefringence of concentrated polymer solutions in two‐dimensional flows

Synopsis The results of flow birefringence measurements are reported for polymer solutions of moderate concentration subjected to a wide range of two-dimensional flows. These flows were generated in a four-roll mill which enables one to systematically vary the ratio of the vorticity to the rate of strain in the flow while holding the velocity gradient constant. It is shown that steady-state birefringence data collected over a wide range of flow types can be correlated against the eigenvalue of the velocity gradient tensor, in agreement with criterion for strong and weak flows from model calculations. Transient birefringence measurements in which purely extensional flows were started from rest are also reported. It was observed that the birefringence went through a pronounced overshoot in time for two different polymer/solvent systems. Flow induced increases in the solution turbidity were also observed and the increased turbidity remained constant over a period of many hours after extensional flows were arrested. The birefringence, on the other hand, decayed to zero almost immediately after the flows were stopped. These changes in the turbidity suggest that crystallization of the polymer was occurring. The qualitative results of experiments are compared to recent network model calculations using the theory of Yamamoto for concentrated polymer systems. It is found that this model can predict qualitatively many of the experimental observations if the function describing the breakage of polymer chain entanglements is allowed to depend on the conformation of the polymer segments bridging the entanglements. In particular, this dependency of the entanglement breakage on the conformation of the network segments leads to a predicted overshoot of birefringence when purely extensional flows are started from rest. It is also demonstrated through this model that birefringence data taken over a wide range of flow types can be used to estimate the degree to which the network deforms affinely with the flow field.
Semaphorin Profiling of Periodontal Fibroblasts and Osteoblasts

Cells of the periodontal attachment (cementoblasts, osteoblasts, and periodontal ligament fibroblasts) are descended from a common progenitor (the cranial neural crest). During their differentiation into different cell types, these cells separate from one another to form a laminated structure. Semaphorins (and their neuropilins and plexin receptors) act as cell guidance molecules for other neural crest derivatives. It is predicted that the differential expression of these molecules will correlate with the ability of these cells to segregate. It is demonstrated that human pre-osteoblasts segregate from PDL and gingival fibroblasts in culture. In addition, these cells express different semaphorins and plexins. Semaphorins 3D and 7A were expressed preferentially in dermal fibroblasts, while semaphorin 6B was selectively expressed by pre-osteoblasts. Semaphorins 3B, 4C, 5B, and 6C and plexins B1 and C1 were expressed in reduced levels in pre-osteoblasts. Analysis of the data suggests that differential express...
Mobility of edge dislocations on {110} planes in tungsten single crystals☆

Abstract The mobility of edge dislocation on (110) type planes was measured in single crystals of electronbeam-melted tungsten at 298°K and 77°K. The stress dependence of the average velocity can be expressed by an equation of the form V = ( τ τ 0 ) m where V is the average velocity in cm/sec and τ is the applied shear stress. The value of m was found to increase with decreasing temperature. A limited number of measurements of strain-rate sensitivity of similar specimens indicate that the power dependence of average dislocation velocity on stress, m, can be determined from strain-rate sensitivity measurements only at very low strain.
Effect of protein and methionine levels in molt diets on postmolt performance of laying hens.

Abstract Three experiments were conducted to evaluate the effects of feeding molt diets varying in protein content and supplemental Met on postmolt layer performance. Laying hens (70, 65, or 96 wk of age) were induced to molt by fasting (feed only) until 26 to 28% body weight loss occurred. Six molt diets consisting of 16, 13, or 10% CP with or without .15% supplemental Met were then fed until egg production reached approximately 10%, at which time all hens received a 16% CP layer diet for 30 wk in Experiments 1 and 2 and for 4 wk in Experiment 3. In Experiment 1 (summer), hens regained body weight more rapidly, returned to production faster, and had larger egg weights (Weeks 1 to 4) when fed the 16 or 13% CP molt diets than when fed the 10% CP molt diet. Long-term egg production, egg yield (grams of egg per hen per day) (Weeks 1 to 30), and feed efficiency (Weeks 1 to 8) were greater for hens fed the 16 or 13% CP molt diets compared with those fed the 10% CP molt diet. The Met supplementation had no effect on postmolt performance. In Experiment 2 (winter), the only significant treatment effect was that Met supplementation increased egg weight (Weeks 1 to 30). Molt diet treatments had no consistent effect on egg specific gravity during the last 4 wk of the postmolt production period in Experiments 1 or 2. The effects of the dietary treatments on early postmolt performance in Experiment 3 (early fall) were similar to those observed in Experiment 1. The present study indicated that protein content, but not Met supplementation, in molt diets influenced postmolt performance of hens during the summer and early fall experiments, but not in the winter experiment.
Local degradation of fibronectin at sites of expression of the transforming gene product pp60src

Local degradation of extracellular fibronectin, a major extracellular adhesive protein, is believed to play an important part in the migration of cells through the extracellular matrix during tumour invasion, morphogenetic movement and trophoblast implantation. Fibronectin is lost from the cell surface after transformation with Rous sarcoma virus (RSV). By using fluorescent and radiolabelled probes covalently coupled to the surface of substrata, we have recently identified a proteolytic activity that is expressed in RSV-transformed cells and is involved in the local degradation of fibronectin at cell-substratum contact sites. Here, we extend the relevance of these findings and gain some insight into the cellular functions of pp60src, the transforming gene product of RSV. We show that newly expressed viral pp60src is localized at the cytoplasmic surface of the cell membrane, corresponding to the cell contact sites where degradation of extracellular fibronectin occurs.
Tarnish Evaluation of Gold-based Dental Alloys

Three commercial gold dental alloys and three ternary (Au-Ag-Cu) alloys of constant nobility were subjected to a standardized test battery for tarnish. The tests included sodium sulfide and artificial saliva solutions, both at 37°C, in sealed containers. Quantitative measurements of tarnish were made from the alloy color change during a three-day exposure. Alloy nobility is a relatively important factor in determining tarnish resistance; however, microstructure can have a negative effect on tarnish resistance. Alloys with a two-phase microstructure produce microgalvanic conditions which lead to either silver chloride or silver sulfide tarnish products. A solution heat treatment improves tarnish resistance by eliminating microstructural inhomogeneities.
Nickel aluminide thin film fabrication via ion beam sputtering of compound targets

Abstract We report recent results from our use of Kaufman-type ion beam sputtering to fabricate boron-doped nickel aluminide thin films on substrates of Si, NaCl, and polycarbonate resin plastic. Compound targets of boron-doped Ni 3 Al were bombarded with ≈1 keV Ar ions to form films having thicknesses up to 2000 A and areas of approximately 2.5 cm × 2.5 cm. Films with Ni/Al ratios similar to the target have been produced on NaCl and Si as determined by instrumental neutron activation analysis. Grazing incidence X-ray diffraction scans show the (111) plane of Ni 3 Al for films grown on NaCl or Si substrates. Monte Carlo simulations of the compound target sputtering process, taking into account primary ion energy, target surface binding energy, beam-target angle and anisotropy of sputtered species, are compared with film composition as determined by INAA. Results from these measurements comprise complementary data for investigating boron distributions in the films via neutron depth profiling.
A synthesis of antibiotic (±)-PS-5.

Abstract A novel method for the formation of antibiotic (±)-PS-5 is described, involving intramolecular cyclization of a β-lactam with a tricarbonyl residue. This procedure represents another application of the enamine-singlet oxygen reaction in synthesis.
Grating coupled enhancement of light emission from IR light emitting diode devices

We report here the electroluminescence in the range of 3-4.5 μm and 6-10 μm from Sb-based type II interband quantum cascade structure LED devices. We measured the light emission from the top surface of the device with different grating structures. We used different etch depths for the grating formation. The light-current-voltage (LIV) characteristics measured at both room and cryogenic temperatures show that the device with 45 degree angle grating and 1.0 μm deep etch onto the GaSb surface has the highest emission power.
Flexural creep behavior of discontinuous thermoplastic composites: Non-linear viscoelastic modeling and time―temperature―stress superposition

Flexural creep behavior of nylon 6/6, polypropylene and high-density polyethylene long fiber thermoplastic (LFT) composites was studied according to ASTM D-2990. Neat polymers were tested for baseline data and compared with the 40 wt.% E-glass reinforced LFTs, all processed by compression molding. All materials exhibited non-linear viscoelasticity and showed a succession in creep resistance consistent with static flexural yield strength. A four parameter empirical model used for short fiber thermoplastics (SFT), proposed by Hadid et al., was found to provide an excellent fit to the experimental data. Time-compliance data from flexural creep and dynamic mechanical analysis (DMA) were combined to utilize short-term flexural creep tests to predict lifetime of the composites. A time-temperature-stress superposition (TTSSP) procedure was used, where stress-based vertical shifts were applied in addition to horizontal shifts used in a traditional time-temperature superposition (TTSP). Master curves obtained by this method projected the long-term creep properties, the order of creep resistance being consistent with the flexural creep data.
An Examination of the Factor Structure of the Index of Race-Related Stress among a Sample of African American Adolescents.

In the present study, the Index of Race-Related Stress (IRRS) was administered to a sample of urban African American adolescents. This instrument has been used among samples of adult and collegiate African Americans, and the purpose of the present study was to examine the factor structure of adolescent responses. The scale was modified and administered to a sample of 324 African American adolescents. The results provided empirical evidence of validity for the IRRS, particularly as a measure of race-related stress among adolescents. The measure required some modifications, which included deletion of items and rewording some questions to make them relevant for an adolescent sample. Future research should consider the assessment of race-related stress among adolescent samples to understand its association with mental and physical health.
Weathering of Mixed-Layer Clays in Soils

The occurrence of mixed-layer clays was noticed in several New England soils; a particularly well developed mixed-layer sequence involving the weathering of randomly inter-stratified vermiculite and illite was intensively studied. Weathering of the interstratified system resulted in the formation of alumina in interlayer positions as evidenced by chemical and x-ray tests. The change in “apparent” spacing of the clay was found to be statistically correlated with sample depth which is in turn related to the intensity of weathering. The change in “vermiculite” spacing from 14.2 to 13.9 A was also found to be correlated with depth. The diffraction effects of the interstratified mineral are discussed in the light of the Hendricks and Teller formula and Mering’s refinement of the formula. The evidence points to the alumina being “brucitic” in character; this modifies the curves calculated by Brown and MacEwan for the randomly interstratified 10 to 14 A mineral. The role of interstratification in the process of soil formation is discussed.
Proconvulsant action of diethyldithiocarbamate in stimulation of the perforant path

The ability of diethyldithiocarbamate (DEDTC) to prolong electrical afterdischarge (AD) and lower the threshold for behavioral seizures elicited by stimulation of the perforant path (PPS) was examined. DEDTC was given in doses of 25, 50, and 100 mg/kg, IP. The effects of DEDTC on the threshold for wet dog shakes (WDS) and the number of WDS elicited by PPS were inconsistent. It had no effect on the duration of AD accompanied with WDS. However, DEDTC, at both 50 and 100 mg/kg, significantly lowered the threshold for rearing accompanied with forelimb clonus. At 100 mg/kg, it also prolonged the duration of AD occurring with these seizures. The effects of DEDTC were transitory and coincided with the time course for its ability to chelate the mossy fiber intravesicular pool of zinc (i.e., that which is released by activation of dentate granule cells). It is suggested that release of zinc from the mossy fibers may serve to protect the hippocampus from paroxysmal seizure activity.
Nodulation of white clover ( Trifolium repens ) in the absence of Rhizobium

Spontaneous nodules developed on the roots of white clover (Trifolium repens cv. Ladino) in the absence ofRhizobium. A small subpopulation of uninoculated clover plants (0.2%) exhibited white, single-to-multilobed elongated structures on their root systems when grown without fixed nitrogen. Clonal propagation using aseptic stolons confirmed the genetic stability of the observation. Few if any viable bacteria of unknown origin were recovered from surfacesterilized structures. Nodule contents were incapable of eliciting nodulation. Histological observations showed that these structures possessed all the characteristic features of indeterminate nodules, such as active meristem, cortex, endodermal layer, vascular strands, and a central zone with parenchyma cells. Infection threads, intercellular or intracellular bacteria were absent. Instead, numerous starch grains were observed in the central zone, a feature absent in normal nitrogen-fixing nodules. Our observation broadens the concept of spontaneous nodulation, believed to be restricted to alfalfa (Medicago sativa), to other legumes, and suggests a degree of generality among indeterminately nodulated legumes displaying natural heterozygosity.
The effect of test variables on the platelet mechanism of erosion

Abstract The validity of the platelet mechanism of solid particle erosion was investigated over a wider range of test conditions than were originally used to develop it. Conditions were selected that were expected to be more favorable for the occurrence of the microcutting mechanism of erosion. It was determined that higher velocities to 130 m s −1 and lower impact angles to α = 20° did not change the basic platelet loss mechanism. Erosion rate changes were determined to relate to the size of the platelets that were formed. An erosion rate peak was observed near the beginning of the erosion process that related to the platelet mechanism of erosion over a relatively large range of particle sizes, velocities and impact angles.
Mechanism of ATP-driven PCNA clamp loading by S. cerevisiae RFC.

Summary Circular clamps tether polymerases to DNA, serving as essential processivity factors in genome replication, and function in other critical cellular processes as well. Clamp loaders catalyze clamp assembly onto DNA, and the question of how these proteins construct a topological link between a clamp and DNA, especially the mechanism by which ATP is utilized for the task, remains open. Here we describe pre-steady-state analysis of ATP hydrolysis, proliferating cell nuclear antigen (PCNA) clamp opening, and DNA binding by Saccharomyces cerevisiae replication factor C (RFC), and present the first kinetic model of a eukaryotic clamp-loading reaction validated by global data analysis. ATP binding to multiple RFC subunits initiates a slow conformational change in the clamp loader, enabling it to bind and open PCNA and to bind DNA as well. PCNA opening locks RFC into an active state, and the resulting RFC·ATP·PCNA(open) intermediate is ready for the entry of DNA into the clamp. DNA binding commits RFC to ATP hydrolysis, which is followed by PCNA closure and PCNA·DNA release. This model enables quantitative understanding of the multistep mechanism of a eukaryotic clamp loader and furthermore facilitates comparative analysis of loaders from diverse organisms.
Reproduction in aging normal and neonatally androgenized female rats.

Decline in reproductive success was compared in normal and neonatally androgenized female rats permitted to receive 1 or 5 ejaculations during each of 7, 5, 3, or 1 mating test. Exposing the females to .5 microgram of testosterone propionate on Day 3 of life increased their age-related rate of decline in the number of successful pregnancies and offspring born in each litter as well as in behavioral receptivity. In both normal and neonatally androgenized animals, fertility and receptivity were greater in animals receiving five ejaculations rather than one ejaculation and in those having multiple pregnancies rather than a single or no prior pregnancy. Perinatally androgenized animals appear to provide a useful model for studying factors influencing age-dependent reproductive processes.
Drosophila peripodial cells, more than meets the eye?

Summary Drosophila imaginal discs (appendage primordia) have proved invaluable for deciphering cellular and molecular mechanisms of animal development. By combining the accessibility of the discs with the genetic tractability of the fruit fly, researchers have discovered key mechanisms of growth control, pattern formation and long-range signaling. One of the principal experimental attractions of discs is their anatomical simplicity — they have long been considered to be cellular monolayers. During larval stages, however, the growing discs are 2-sided sacs composed of a columnar epithelium on one side and a squamous ‘peripodial’ epithelium on the other. Recent studies suggest important roles for peripodial epithelia in processes previously assumed to be confined to columnar cell monolayers. BioEssays 23:691‐697, 2001. fl 2001 John Wiley & Sons, Inc.
Human and murine high endothelial venule cells phagocytose apoptotic leukocytes.

Abstract Apoptotic cell death occurs during normal lymphocyte development and differentiation as well as following lymphocyte exposure to endogenous corticosteroids released during stress, malnutrition, and trauma. Recognition and engulfment of these apoptotic cells is important for the clearance of dying cells before they release potent inflammatory mediators into the vasculature or tissues. Phagocytosis of apoptotic cells is accomplished in part by macrophages. We report for the first time that apoptotic lymphocytes are also phagocytosed by high endothelial venule (HEV) cells. The murine HEV cell line mHEVa rapidly phagocytosed apoptotic lymphoid and myeloid cells with the greatest rate of phagocytosis occurring at 0–6 h. To confirm HEV cell interaction with apoptotic cells, we demonstrated that apoptotic human tonsil lymphocytes were phagocytosed by human tonsil HEV cells in primary cultures. Furthermore, we examined HEV cell phagocytosisin vivo.Mice were treated with a natural corticosterone (4-pregnene-11β,21-diol-3,20-dione) at levels detected during stress or malnutrition (93–180 μg serum cortisol/dl). At 4–12 h posttreatment, apoptotic lymphocytes were present inside vacuoles of HEV cells in axillary lymph node tissue sections, as determined by transmission electron microscopy. These data suggest that, in addition to macrophages, lymph node HEV cells also play a role in the removal of apoptotic lymphocytes. Moreover, since HEV cells are specialized endothelial cells that regulate lymphocyte migration into peripheral lymphoid tissues, they may provide an important checkpoint for clearance of apoptotic lymphocytes within the vasculature, as well as limiting entrance of nonfunctional lymphocytes into the lymph node.
Do language barriers affect trade

Abstract Language barriers may be more important to international trade than previously thought. The Language Barrier Index, a newly constructed variable that uses detailed linguistic data, is used to show that language barriers are significantly negatively correlated with bilateral trade.
Gamma-aminobutyric acid and alcohol actions: Neurochemical studies of long sleep and short sleep mice

Abstract Effects of ethanol and pentobarbital on the GABA receptor-chloride channel complex were evaluated in mice selected for differential sensitivity to the hypnotic effects of ethanol (long sleep and short sleep lines). 36 Cl − influx, [ 35 S]t-butylbicyclophosphorothionate (TBPS) and [ 3 H]muscimol binding were measured in a membrane vesicle suspension (microsacs) from cerebellum or forebrain. Muscimol was found to be a more potent stimulator of 36 Cl − flux in the LS cerebellum, as compared to the SS cerebellum, but a similar maximal level of uptake was achieved in the two lines. Muscimol displaced [ 35 S]TBPS (a ligand for the convulsant site) from cerebellar microsacs, and LS mice were also more sensitive than SS mice to this action of muscimol. However, the number or affinity of high affinity [ 3 H]muscimol binding sites did not differ between the lines. Physiologically relevant concentrations of ethanol (15–50 mM) potentiated muscimol stimulation of 36 Cl − uptake in LS cerebellum but had no effect in SS cerebellum. Ethanol failed to alter stimulated chloride flux hippocampal microsacs from either line. Both the LS and SS lines responded similarly to pentobarbital potentiation of muscimol stimulated chloride uptake regardless of brain region. The demonstrated difference between the LS and SS mice in muscimol stimulated chloride uptake as well as in muscimol displacement of [ 35 S]TBPS binding offers a biochemical explanation for the line differences in behavioral responses to GABAergic agents. Moreover, the findings suggest that genetic differences in ethanol hypnosis are related to differences in the sensitivity of GABA-operated chloride channels to ethanol.
The face-detection effect

We found that briefly flashed pictures of a face were detected more accurately than was a control pattern with a nose, a mouth, and a pair of eyes positioned arbitrarily so that they did not form a face. It has been known for some time that a face, as an organized set of features, is remembered more easily than is any one of its isolated features. Our results show that the perceptual superiority of faces extends to detection tasks, in which there is no need to remember any aspect of the face.
Use of Pitzer Equations to Examine the Formation of Mercury(II) Hydroxide and Chloride Complexes in NaClO4 Media

The thermodynamic stability constants for the hydrolysis and formation of mercury (Hg2+) chloride complexes $$ \hbox{Hg}^{2+} + n\hbox{H}_{2}\hbox{O} = \hbox{Hg(OH)}_n^{(2-n)+} + n\hbox{H}^{+ } \quad\quad \beta_n $$ $$ \hbox{Hg}^{2+} + n\hbox{Cl}^{-} = \hbox{HgCl}_n^{(2-n)+ } \quad\quad \beta_i $$ have been used to calculate the activity coefficients for Hg(OH) (2–)+ and HgCl (2–)+ complexes using the Pitzer specific interaction model. These values have been used to determine the Pitzer parameters for the hydroxide and chloro complexes $$(\beta_{\rm ML}^{(0)}, \,\beta_{\rm ML}^{(1)}$$ and C ML). The values of $$\lambda_{ij}$$ and $$\zeta_{ijk}$$ have been determined for the neutral complexes (Hg(OH)2 and HgCl2). The resultant parameters yield calculated values for the measured values of log $$\beta^{\ast}$$ to ±0.01 from I = 0.1 to 3 m at 25°C. Since the activity coefficients of $$\hbox{Hg(OH)}_n^{(2-n)+}$$ and $$\hbox{HgCl}_n^{(2-n)+}$$ are in reasonable agreement with the values for Pb(II), we have estimated the effect of temperature on the chloride constants for Hg(II) from 0 to 300°C and I = 0–6 m using the Pitzer parameters for $$\hbox{PbCl}_n^{(2-n)+}$$ complexes. The resulting parameters can be used to examine the speciation of Hg(II) with Cl− in natural waters over a wide range of conditions.
Exotic science and domestic exoticism: Theodore Roosevelt and J. A. Leite Moraes in Amazonia

Exotic science and domestic exoticism: Theodore Roosevelt and J. A. Leite Moraes in Amazonia
The Influence of Financial Factors on Motivation to Save among Poor Individuals

This cross-sectional study of N = 194 low-income individuals compared socio-demographic and finance-related factors between those who reported having a motivation to save and those who did not report having some motivation to save. Theories and factors related to saving are reviewed. Logistic regression tests found that paying rent with cash, using voluntary income tax assistance to prepare taxes, and witnessing parents save money through financial institutions were positively associated with the likelihood of having a motivation to save. Overall, the study supports the significance of financial socialization and institutional mechanisms of saving. Discussions are directed toward efforts to help lower income families save.
Diminution of Imipramine Mortality in Hypothyroid Mice

A PREVIOUS report described enhancement of imipramine toxicity in hyperthyroid mice1. This work had been prompted by the observation of a clinical case in which the simultaneous exhibition of imipramine and thyroid hormone had preceded a bout of paroxysmal auricular tachycardia2. Although we had no similar clinical experience to commend our present work, we nevertheless considered it of interest to test the effect of hypothyroidism on imipramine mortality.
Selective reduction of acardiac twin by radiofrequency ablation

Abstract Objective: Acardiac/acephalic twinning is a rare anomaly in which a normal "pump" twin perfuses an acardiac twin, which results in twin reversed arterial perfusion sequence. A novel technique for selective reduction and obliteration of blood flow in the acardiac twin is described. Study Design: Thirteen consecutive cases of monochorionic twin gestation with twin reversed arterial perfusion sequence underwent selective reduction of the abnormal twin with the use of radiofrequency ablation. Under direct real-time sonographic guidance, a 3-mm (14-gauge) radiofrequency ablation needle was percutaneously inserted through the maternal abdominal wall into the intrauterine fetal abdomen at the level of the cord insertion site of the acardiac twin. Energy was applied until termination of blood flow to the acardiac fetus was documented by Doppler ultrasound scanning. Results: All 13 mothers tolerated the procedure without major complications. All 13 "pump" fetuses have been delivered. Twelve of 13 infants are alive and well. The first patient in this series was delivered at 24.4 weeks and the infant subsequently died from complications of prematurity. Average gestational age at intervention was 20.7 weeks, and the average gestational age at delivery was 36.2 weeks. Conclusion: Radiofrequency ablation is a minimally invasive, percutaneous technique that can effectively obliterate blood supply to an acardiac twin to preserve and protect the pump twin. (Am J Obstet Gynecol 2002;187:635-40.)
The lifeShirt : an advanced system for ambulatory measurement of respiratory and cardiac function

An accurate ambulatory breathing monitor is needed to observe acute respiratory changes in patients with medical or psychological disorders outside the clinic (e.g., hyperventilation during panic or apneas during sleep). Significant limitations of existing monitors are size, troublesome operation, and difficulty holding chest and abdomen bands in place during 24-hour recordings. Recently, a garment has been developed with embedded inductive plethysmography sensors for continuous ambulatory monitoring of respiration, heart activity, inductive cardiography, motility, postural changes, and other functions. The signals are displayed and stored on a handheld computer (Visor), and then analyzed offline, extracting more than 40 clinical parameters relating to cardiorespiratory function (e.g., heart rate, respiratory sinus arrhythmia, tidal volume, stroke volume, pre-ejection period, apnea-hypopnea index, thoraco-abdominal coordination, sighing). The device also serves as an electronic diary of symptoms, moods, and activities. This advanced system may open a new era in ambulatory monitoring for clinical practice and scientific research.
The Role of the Assessment Coordinator in a Division of Student Affairs.

This chapter describes the emerging role of assessment coordinators in student affairs divisions. It highlights opportunities and challenges in that role along with key findings from assessment projects.