cssi/SciSciGPT-SciSciNet huggingface dataset:
The elevational ascent and spread of invasive annual grass dominance in the Great Basin, USA

Aim: In the western US, sagebrush (Artemisia spp.) and salt desert shrublands are rapidly transitioning to communities dominated by exotic annual grasses, a novel and often self-reinforcing state that threatens the economic sustainability and conservation value of rangelands. Climate change is predicted to directly and indirectly favor annual grasses, potentially pushing transitions to annual grass dominance into higher elevations and north-facing aspects. We sought to quantify the expansion of annual grass-dominated vegetation communities along topographic gradients over the past several decades. Location: Our analysis focused on rangelands among three ecoregions in the Great Basin of the western US, where several species of exotic annual grasses are widespread among shrub and perennial grass-dominated vegetation communities. Methods: We used recently developed remote sensing-based rangeland vegetation data to produce yearly maps of annual grass-dominated vegetation communities spanning the period 1990-2020. With these maps, we quantified the rate of spread and characterized changes in the topographic distribution (i.e., elevation and aspect) of areas transitioning to annual grass dominance. Results: We documented more than an eight-fold increase in annual grass-dominated area (to >77,000 km2) occurring at an average rate of >2,300 km2 yr-1. In 2020, annual grasses dominated one fifth (19.8%) of Great Basin rangelands. This rapid expansion is associated with a broadening of the topographic niche, with widespread movement into higher elevations and north-facing aspects. Main conclusions: Accelerated, strategic intervention is critically needed to conserve the fragile band of rangelands being compressed between annual grassland transitions at lower elevations and woodland expansion at higher elevations.
Permafrost distribution in the southern part of the discontinuous zone in Québec and Labrador

The distribution of permafrost in the southern part of the discontinuous zone in Quebec and Labrador is described. At the southern limit of this subzone islands of permafrost vary in extent from a few tens of square metres to several hectares and in thickness from a few centimetres to a metre or so. Northward to the middle of the discontinuous zone permafrost becomes increasingly widespread reaching a thickness exceeding 100 metres. Permafrost occurs mainly in peatlands, on some north facing slopes and above treeline on mountain summits. The relationships of permafrost distribution to climatic and terrain factors, including air temperature, vegetation, drainage and snow cover are discussed, the last being particularly important. The paper concludes with an analysis of some prominent air photo patterns.
The Case for Omega_M = 0.33 +/- 0.035

For decades, the determination of the mean density of matter(Omega_M) has been tied to the distribution of light. This has led to a ``bias,'' perhaps as large as a factor of 2, in determining a key cosmological parameter. Recent measurements of the physical properties of clusters, cosmic microwave background (CMB) anisotropy and the power spectrum of mass inhomogeneity now allow a determination of Omega_M without ``visual bias.'' The early data lead to a consistent picture of the matter and baryon densities, with Omega_B = 0.039 +/- 0.0075 and Omega_M = 0.33 +/- 0.035.
Structure and Dynamics of Biological Systems: Integration of Neutron Scattering with Computer Simulation

The combination of molecular dynamics simulation and neutron scattering techniques has emerged as a highly synergistic approach to elucidate the atomistic details of the structure, dynamics, and functions of biological systems. Simulation models can be tested by calculating neutron scattering structure factors and comparing the results directly with experiments. If the scattering profiles agree, the simulations can be used to provide a detailed decomposition and interpretation of the experiments, and if not, the models can be rationally adjusted. Comparison with neutron experiment can be made at the level of the scattering functions or, less directly, of structural and dynamical quantities derived from them. Here, we examine the combination of simulation and experiment in the interpretation of SANS and inelastic scattering experiments on the structure and dynamics of proteins and other biopolymers.
Signal recovery from Pooling Representations

In this work we compute lower Lipschitz bounds of lp pooling operators for p = 1, 2, ∞ as well as lp pooling operators preceded by half-rectification layers. These give sufficient conditions for the design of invertible neural network layers. Numerical experiments on MNIST and image patches confirm that pooling layers can be inverted with phase recovery algorithms. Moreover, the regularity of the inverse pooling, controlled by the lower Lipschitz constant, is empirically verified with a nearest neighbor regression.
A SPICE macromodel for an adjustable positive voltage regulator

A macromodel has been developed for the LM117 adjustable positive voltage regulator. This model predicts AC, DC, transient, and power-up responses. Design formulas for finding the component values of the macromodel which are based on pin measurements are presented. The methodology of development is presented along with experimental and simulated results. >
Inapproximability of hypergraph vertex cover and applications to scheduling problems

Assuming the Unique Games Conjecture (UGC), we show optimal inapproximability results for two classic scheduling problems. We obtain a hardness of 2 - e for the problem of minimizing the total weighted completion time in concurrent open shops. We also obtain a hardness of 2 - e for minimizing the makespan in the assembly line problem. These results follow from a new inapproximability result for the Vertex Cover problem on k-uniform hypergraphs that is stronger and simpler than previous results. We show that assuming the UGC, for every k ≥ 2, the problem is inapproximable within k - e even when the hypergraph is almost k-partite.
Impact of the Kenya Cash Transfer for Orphans and Vulnerable Children on early pregnancy and marriage of adolescent girls

There is promising evidence that poverty-targeted cash transfer programs can have positive impacts on adolescent transitions to adulthood in resource poor settings, however existing research is typically from small scale programs in diverse geographic and cultural settings. We provide estimates of the impact of a national unconditional cash transfer program, the Kenya Cash Transfer for Orphans and Vulnerable Children, on pregnancy and early marriage among females aged 12 to 24, four years after program initiation. The evaluation was designed as a clustered randomized controlled trial and ran from 2007 to 2011, capitalizing on the existence of a control group, which was delayed entry to the program due to budget constraints. Findings indicate that, among 1549 females included in the study, while the program reduced the likelihood of pregnancy by five percentage points, there was no significant impact on likelihood of early marriage. Program impacts on pregnancy appear to work through increasing the enrollment of young women in school, financial stability of the household and delayed age at first sex. The Kenyan program is similar in design to most other major national cash transfer programs in Eastern and Southern Africa, suggesting a degree of generalizability of the results reported here. Although the objective of the program is primarily poverty alleviation, it appears to have an important impact on facilitating the successful transition of adolescent girls into adulthood.
A Review of “The Great African War: Congo and Regional Geopolitics, 1996–2006”: Reyntjens, Filip, New York: Cambridge University Press, 340 pp., $28.99, ISBN 978-0521169059, Publication Date: August 2010

Filip Reyntjens is one of only a handful of scholars capable of writing such a comprehensive account of the Congo War, which started in 1996 and continues unabated today. Reyntjens elucidates the c...
NUCLEON AND CHARGED-PION ALBEDO SPECTRA IN AN ACCELERATOR CAVE FROM 200 GeV PROTON INTERACTIONS IN IRON.

Abstract Nucleon and charged-pion albedo flux distributions in an accelerator cave resulting from the interaction of 200 GeV protons have been calculated. The spectra are given as a function of secondary-particle energy and of radial position and distance from the point where the beam is dumped into the iron. Comparisons between the omnidirectional and “backward” flux distributions are presented.
Commentary on Immune System Associated Diseases Caused by Viruses: The Role of EBV

In her review using the human Epstein–Barr virus (EBV) as an example, Dr. Chen intends to illustrate how host immune systems have evolved in response to pathogens or in many cases co-evolved with pathogens. She discusses why EBV in most people causes what appears to be a self-limiting lymphoproliferative disease (or is it? See her discussion of autoimmune diseases and EBV), but in a very small proportion of individuals the virus causes malignant diseases of severe consequence. She reviews some of the plausible explanations that may include interactions of environmental and host genetic factors resulting in EBV associated malignancies. She points out that EBV may not merely transform B cells, but it could also impact the host immune system on a much more global basis than previously realized. She also suggests that EBV associated diseases, in lieu of reflecting the pathogenic potential of the virus, are actually a reflection of the genetic predisposition of certain populations to the modulate immune system inappropriately in response to the virus infection. She supports this notion by detailing the abnormal modulation of NKT cells when the host is infected with EBV. For example, she cites a study that shows that the frequencies of regulatory CD8 + NKT, but not CD4 + NKT cells, in EBV associated Burkitt's lymphoma (BL) and nasopharyngeal carcinoma (NPC) patients are much lower than CD8 + NKT levels in healthy EBV carriers (Yuling et al., 2009), concluding that a skewed NKT cell response might modify the pathogenesis caused by the virus. She also supports her supposition that EBV pathogenesis is likely due to improper immune modulation in response to the infection by reviewing the data associating autoimmune diseases with EBV infections, especially focusing on multiple sclerosis (MS). She cites a study by Serafini et al. (2007) in which it was found that that almost 100% of the early onset MS cases with the secondary progressive phase contain dysregulated EBV infected plasma cells in MS brains. She also reviews other studies that describe atypical responses of MS patients who have been exposed to EBV. Nevertheless, the cause and effect link, EBV to MS, is still tenuous, yet intriguing. She concludes that the malignancies associated with EBV infection and especially the autoimmune diseases associated with EBV infection may result from human genetic variations that cause the host to differentially modulate the immune response to EBV infection to the detriment of the host.
Forage Species in Lakes and Reservoirs of the Western United States

Abstract Fisheries management in the western United States has concentrated on salmonid species, particularly in streams. Forage-fish management in lakes and reservoirs is not highly developed, and has emphasized introductions of both predators and prey. In coldwater lakes, kokanees Oncorhynchus nerka have been established widely as the principal forage for salmonids and often support a sport fishery themselves. Introductions of other forage organisms in coldwater lakes and reservoirs, notably the opossum shrimp Mysis relicta and redside shiner Richardsonius balteatus have had mixed results due in part to food competition with resident species. A variety of exotic predator and prey species have been introduced in coolwater and warmwater reservoirs. Results have varied greatly, and include establishment of successful sport fisheries, elimination of native fishes, failure of introduced predators or prey, and predation on stocked salmonids. Native forage species generally have been overlooked by management, ...
Lunar Diurnal Atmospheric Tide

Haurwitz and Chapman1 have recently described the discovery, analysis and distribution of the lunar semidiurnal air tide. There is, in addition to lunar semidiurnal excitation, a smaller lunar diurnal gravitational excitation. Although there must be some atmospheric response to this excitation, it has not yet been found in the data.
Thyroid cytology and histology.

Fine needle aspiration (FNA) is an economical procedure that allows prompt evaluation of a thyroidal mass. Careful attention to each step of the aspiration will allow good specimens to be obtained. The cytopathologist should obtain the aspirates or else should accompany the clinician performing the aspirations. Unsatisfactory specimens should constitute less than 5% of the total. Reliable diagnoses can be made of papillary carcinoma, medullary carcinoma, anaplastic carcinoma, chronic lymphocytic thyroiditis, benign cystic lesions and the usual colloid-rich adenomatoid nodules. The diagnosis of follicular neoplasms and some cellular adenomatoid nodules remains problematical. Therefore, some thyroid operations inevitably yield benign follicular lesions.
Assessing housing growth when census boundaries change

The US Census provides the primary source of spatially explicit social data, but changing block boundaries complicate analyses of housing growth over time. We compared procedures for reconciling housing density data between 1990 and 2000 census block boundaries in order to assess the sensitivity of analytical methods to estimates of housing growth in Oregon. Estimates of housing growth varied substantially and were sensitive to the method of interpolation. With no processing and areal-weighted interpolation, more than 35% of the landscape changed; 75-80% of this change was due to decline in housing density. This decline was implausible, however, because housing structures generally persist over time. Based on aggregated boundaries, 11% of the landscape changed, but only 4% experienced a decline in housing density. Nevertheless, the housing density change map was almost twice as coarse spatially as the 2000 housing density data. We also applied a dasymetric approach to redistribute 1990 housing data into 2000 census boundaries under the assumption that the distribution of housing in 2000 reflected the same distribution as in 1990. The dasymetric approach resulted in conservative change estimates at a fine resolution. All methods involved some type of trade-off (e.g. analytical difficulty, data resolution, magnitude or bias in direction of change). However, our dasymetric procedure is a novel approach for assessing housing growth over changing census boundaries that may be particularly useful because it accounts for the uniquely persistent nature of housing over time.
Selection criteria for successful immediate breast reconstruction.

To evaluate the factors leading to success in immediate breast reconstruction after mastectomy, 176 consecutive immediate reconstruct ions done with implants or expanders over a 5-year period were analyzed. None of these 176 had “complete muscle coverage.” There were only five failures: four with implant loss (one involving radiation) and one removed electively. The failures were 1 in 40 regular implants, 4 in 77 temporary expanders, and 0 in 59 long-term expanders. There is no other report in the literature comparing these different types of implants. Various hypotheses for failure are reviewed. It is concluded that failure in immediate reconstruction is not related to use of drains, bilaterality, or lack of “complete muscle coverage.” It is concluded that failure is related to implant type, prior radiation, and most of all to suboptimal patient selection. Specific selection criteria and operative techniques are discussed.
Chandra HRC-S degapping corrections

The HRC-S is a microchannel plate detector on board Chandra and is primarily used for spectroscopic observations with the Low Energy Transmission Grating Spectrometer (LETGS) in place. Photons are detected via signals read out from evenly spaced wires underneath the plates and positions are computed by centroiding around the strongest amplifier signals. This process leads to gaps in between the taps where no events are placed. A deterministic correction is then made during ground processing to these event locations to remove the gaps. We have now developed a new, empirical degap corrections from flight data. We describe the procedure we use, present comparisons between the new degap and lab-data based degap, and investigate the temporal stability of the degap corrections.
Explanation and Mental Causation

Malgre la tendance actuelle a privilegier l'epistemologie sur la metaphysique, l'A. montre que l'efficacite explicative des proprietes mentales, ainsi que la deduction de la notion de causalite a partir du concept d'explication, ne suffisent pas a resoudre le probleme de la causation mentale.
Muscle Layer Contractile Activity of the in Vitro Rabbit Uterus

Discussion and SummaryAnalyses of rabbit myometrial longitudinal and circular muscle activity indicate that these two muscle layers contract simultaneously in vitro. Simultaneous contractions of the longitudinal fibers were recorded by the Grass tranducer and the longitudinal ECFT (Fig. 4). Tone levels of bursts recorded by the longitudinal ECFT have been observed to be a function of the tension set on the underlying muscle at the time of ECFT attachment. If this tension was large, a decreased tone was recorded; if small, an increased tone was recorded. This apparent decreased tone was likely induced by contraction of adjacent longitudinal muscle above and below the ECFT.
Effect of Single Inocula of Endamoeba histolytica Trophozoites on Guinea Pigs.

SummaryGuinea pigs were inoculated intracecally with graded single doses of from 100 to 5,000,000 amebae. None of the animals that were given less than 1,000 amebae developed infection. The 50% infective dose under the experimental conditions was 10,000 amebae. The mean weight of the guinea pigs that later became infected was significantly smaller than that of those which resisted infection. Thirty-one out of 50 guinea pigs that received single inocula of from 5,000 to 5,000,000 amebae died as a result of the infection. The LD50 under the experimental conditions was 63,000 amebae. Death occurred in all cases between 5 and 17 days after inoculation, on the average 9.3 days after inoculation, and the greatest number of guinea pigs died on the eighth day. In general, the size of the inoculum was found to have an inverse relationship to the average time between inoculation and death. Histopathologic studies confirmed necropsy examination. All animals found to be positive by gross examination and by direct sme...
In vivo assays to study histone ubiquitylation

The importance of histone acetylation, phosphorylation, and methylation in transcription and other DNA-mediated processes is now well established. Histones are also ubiquitylated, but in contrast to the majority of ubiquitylated proteins, ubiquitylated histones are not generally targeted for degradation and may play roles similar to those of other histone modifications. Antibodies against acetylated histones have provided unique insights into the regulation, distribution, and cellular roles of these modified histones. In this report, we describe methods to identify ubiquitylated histones in budding yeast and HeLa cells. We provide protocols to detect ubiquitylated histones that are based on a combination of in vivo genetic and immunological assays. These methods should provide relatively simple and useful tools to study the global regulation of this important but poorly understood histone modification.
Effect of Topical Adenosine Deaminase Treatment on the Functional Hyperemic and Hypoxic Responses of Cerebrocortical Microcirculation

The purpose of this study was to investigate the possible importance of adenosine in cerebrocortical vasodilatation accompanying brain activation (epileptic seizures and direct electrical stimulation) and hypoxia (arterial hypoxia and cyanide poisoning of the brain cortex). In chloralose-anesthetized cats a circumscribed area of the brain cortex was treated with adenosine deaminase (Type III; Sigma), which potently deaminates adenosine to the nonvasoactive inosine. Cerebrocortical vascular volume and fluorescence of reduced nicotinamide adenine dinucleotide were measured in vivo by surface fluororeflectometry. The responses of small pial and intracortical vessels to brain activation and hypoxia were studied in brain cortices superfused with artificial (mock) CSF and 5 U/ml adenosine deaminase. It was found that superficially applied adenosine deaminase readily diffuses onto the brain cortex. Prolonged pretreatment of the brain cortices with 0.025 U/ml adenosine deaminase eliminated almost completely the v...
Intentional change theory at the organizational level: a case study

Purpose – The purpose of this paper is to examine the application of intentional change theory (ICT) at the organizational level through the lens of a case study.Design/methodology/approach – This paper is a case study of Roadway Express, a leading transportation provider of industrial and commercial goods throughout North America, which embarked on a journey of cultural transformation in 1999, using a popular change process known as appreciative inquiry (AI). The Roadway case study illustrates both the theory of intentional change and the method of AI in use and provides a platform upon which to observe change at the organizational level.Findings – Roadway Express serves as a solid benchmark for organizations considering how to succeed in cultural transformation. The implementation of the philosophy and methodology of appreciative inquiry, played a key role in that success. Analysis shows the link between ICT and AI. From this observation, ICT emerges as a stand‐along theory upon which to interpret the s...
Effects of age on the thickness of myelin sheaths in monkey primary visual cortex.

The effect of age on myelin sheath thickness was determined by an electron microscopic examination of cross sections of the vertical bundles of nerve fibers that pass through primary visual cortex of the rhesus monkey. The tissue was taken from the cortices of young (4-9 years of age) and old (over 24 years of age) monkeys, and the sections were taken at the level of layer 4Cbeta. From the electron photomicrographs, the diameters of axons and the numbers of lamellae in their myelin sheaths were determined. No change was found in the diameters of axons with age, although the mean numbers of myelin lamellae in the sheaths increased from 5.6 in the young monkeys to 7.0 in the old monkeys. Much of this increase in mean thickness was due to the fact that, in the old monkeys, thick myelin sheaths with more than ten lamellae are more common than in the young monkeys. While this increase in the thickness of myelin sheaths is occurring in old monkeys, there are also age-related changes in some of the sheaths. Consequently, it seems that, with age, there is some degeneration of myelin but, at the same time, a continued production of lamellae.
Ectopic Lacrimal Gland Cyst of the Orbit

Ectopic lacrimal gland tissue is most common in the eyelid, conjunctiva, and cornea, but may also be found in the uvea or orbit. A 7-year-old boy developed a mass in the anterior superiomedial orbit close to the trochlea. A superior medial orbitotomy, done when the boy was 9 years old, disclosed a tense, thin-walled, fluid-filled cyst containing a small nest of normal lacrimal gland with a large capsule of fibrous tissue containing areas of singly layered epithelial cells.
Trade Spaces in Crewed Spacecraft Atmosphere Revitalization System Development

Developing the technological response to realizing an efficient atmosphere revitalization system for future crewed spacecraft and space habitats requires identifying and describing functional trade spaces. Mission concepts and requirements dictate the necessary functions; however, the combination and sequence of those functions possess significant flexibility. Us-ing a closed loop environmental control and life support (ECLS) system architecture as a starting basis, a functional unit operations approach is developed to identify trade spaces. Generalized technological responses to each trade space are discussed. Key performance parameters that apply to functional areas are described.
Simulation and evaluation with energy systems blocks

Abstract By using blocks programmed for each symbol, models using energy systems language can now be computer-simulated directly, by-passing the mathematics, which is done automatically. Energy systems methodology was introduced in 1967 to help aggregate systems overview and connect human verbal thinking to quantitative models constrained by principles of energy and hierarchy. The GENSYS library of symbol blocks for the simulation program EXTEND, when connected on screen, sets up a system of equations and generates output graphs by sending information back and forth between the blocks. The process of programming helped define EMERGY (spelled with an ‘m’), empower and transformity mathematically so that the simulations can plot quantity, flow, EMERGY, empower and transformity. Examples include ecological and economic systems. Blocks and models for elementary teaching use pictorial icons, which help bring systems modeling and simulation to general education without the necessity of writing equations. This paper explains the modeling concepts and how to prepare and use blocks.
Integrated rural development programmes: A historical perspective

Abstract The pervasive poverty in rural areas has represented a continuing concern of national governments and development assistance agencies. One response to pervasive poverty has been the design of local institutions to enable rural communities to mobilize their own resources to generate growth and improve the quality of life. Programmes organized under the rubric of ‘community development’ were a major focus of development assistance during the 1950s and early 1960s. During the early 1970s concern about the distributional implications of economic growth again emerged as a major theme in development thought and development policy. This concern gave rise to two new development assistance approaches — ‘integrated rural development’ and ‘basic needs’ programmes. In this paper, I attempt to trace the development, accomplishments and limitations of the community development, integrated rural development and basic needs approaches.
Computing and Partitioning Cloud Feedbacks Using Cloud Property Histograms. Part I: Cloud Radiative Kernels

AbstractThis study proposes a novel technique for computing cloud feedbacks using histograms of cloud fraction as a joint function of cloud-top pressure (CTP) and optical depth (τ). These histograms were generated by the International Satellite Cloud Climatology Project (ISCCP) simulator that was incorporated into doubled-CO2 simulations from 11 global climate models in the Cloud Feedback Model Intercomparison Project. The authors use a radiative transfer model to compute top of atmosphere flux sensitivities to cloud fraction perturbations in each bin of the histogram for each month and latitude. Multiplying these cloud radiative kernels with histograms of modeled cloud fraction changes at each grid point per unit of global warming produces an estimate of cloud feedback. Spatial structures and globally integrated cloud feedbacks computed in this manner agree remarkably well with the adjusted change in cloud radiative forcing. The global and annual mean model-simulated cloud feedback is dominated by contri...
The bacteriological status of a specific-pathogen-free animal production building and of its staff and the microbiological integrity of the animals one year after the building was commissioned

Bacteriological contamination of a specific-pathogen-free (SPF) animal production building was more extensive after one year of operation than at the time of commissioning. Throat and nose swabs taken from the staff yielded a number of undesirable organisms, in particular, on one occasion, a Group A streptococcus. It is recommended that a closer bacteriological scrutiny of the staff of SPF production buildings ought perhaps to be made in the light of these findings.
Effect of catecholamines on lipolysis and esterification in vitro in adipose tissue of sheep fed low and high energy diets

Abstract The purpose of this study was to determine effects of the catecholamines clenbuterol, norepinephrine, and isoproterenol (10−5 m ), and dibutyryl-cyclic AMP (20 mmol/L on lipolysis and palmitate esterification in subcutaneous adipose tissue from sheep when fed a low energy diet, and then again when fed a high energy diet ad libitum. On the low energy diet, all catecholamines and cyclic AMP were lipolytic, and all inhibited palmitate esterification by 48% or more. When fed the high energy diet for 6 wk, only isoproterenol and cyclic AMP were lipolytic and inhibitory toward palmitate esterification, but less so than when sheep were fed the low energy diet. Blood plasma concentrations were not different for glucose, but free fatty acid greater and insulin concentrations lower for low energy-fed than for high energy-fed sheep. The mechanism for the altered catecholamine potency in ovine adipose tissue when sheep were fed the high energy diet is not clear; however, regulation of adrenergic receptors by changes in hormonal and/or metabolite balance because of diet were likely involved.
Single- vs. multi-orbital theories of the cuprate superconductors: exact results on finite lattices

Abstract We present a comparative exact diagonalization study of single- and three-orbital Hubbard models for cuprate superconductors in their respective strong-coupling limits. For the simplest case of the three-orbital model, our results indicate a close quantitative correspondence with the single-orbital model, both in the groundstate properties and in the low-energy excitation spectra, consistent with the theory of Zhang and Rice.
An ultrastructural study of postprandial changes in bone lining cells of lead-injected thyroidectomized and thyroid-intact rats.

This report is an electron microscopic study demonstrating intracellular differences in endosteal bone lining cells in tissue removed from thyroid-intact (TI) and thyroidectomized (TX) rats. Rats with functional parathyroid gland transplants, many of which were thyroidectomized, were trained to a 0900 h feeding schedule. Some of the TX rats (TX + CT) were injected postprandially with calcitonin (80 pg/g body weight). One hour before sacrifice all rats were injected with lead acetate (20 mg/kg body weight). Sections of the diaphysealmetaphyseal junction of the tibia were prepared for morphological examination using two procedures designed for the study of nondecalcified bone tissue. The following results were obtained: (a) Following pyroantimonate fixation, the electron-dense precipitate in sections obtained from TI and TX + CT rats was arranged in a distinct intracellular organization within bone lining cells. Following an anhydrous tissue preparation (in ethylene glycol), the mitochondria of these cells contained distinct electron-lucent areas. A similar result was found in tissue from TI rats regardless of the relationship of the time of sacrifice to the last feeding. (b) In TX rats, the major difference in the appearance of these bone lining cells was in tissue removed 4 h following a calcium-containing meal. The electron-dense precipitate (resulting from pyroantimonate fixation) was diffusely distributed throughout the lining cells rather than organized. The mitochondria of the cells (anhydrous procedure) contained distinct electrondense areas. These marked differences in tissues from TX rats were transient. With time following feeding, the histological appearance of these cells returned to that seen in cells from TI rats and TX rats injected postprandially with calcitonin. These results, utilizing the unique reaction of lead with bone cells, demonstrate an additional calcitonin-dependent response of rats to oral intake of calcium. They support the concept that endosteal bone tissue contains target cells for calcitonin and that this hormone has a role in postprandial conservation and storage of calcium.
A hypertensive syndrome with relative adrenal cortical overactivity.

The authors have used the concentration of salt in sweat as an objective test to demonstrate the existence of a group of hypertensive patients with clinical signs of hyperadrenocortical function. The significantly lower concentration of salt in the sweat of patients with this endocrine hypertensive syndrome distinguishes them from other hypertensive patients who show no significant difference from normal. That this difference reflects an adrenal pathway is further suggested by Conn's demonstration that hypoadrenal activity is associated with high concentrations, and hyperadrenal function with low concentrations of salt in sweat.
DISSIPATIVE HAMILTONIAN SYSTEMS: A UNIFYING PRINCIPLE

Abstract The concept of hamiltonian sysem is generalized to include a wide class of dissipative processes. Evolution of any observable is generated jointly by a hamiltonian, with an entropy-conserving Poisson bracket, and an entropy, with an energy-conserving dissipative bracket. This approach yields many of the standard kinetic equations, such as those representing particle collisions, three-wave interactions, and wave-particle resonances.
Epidural Spinal Cord Stimulation: Anatomical and Electrical Properties of the Intraspinal Structures Relevant to Spinal Cord Stimulation and Clinical Correlations

Epidural spinal cord stimulation (SCS) has gained a secure place in the armamentarium of the surgeon treating chronic pain conditions (1, 2). The complexity of the intraspinal structures and their different susceptibility to electrical signals, however, has made it difficult to characterize the effects of the stimulation, Some important recent work has helped shed light on the electrical properties of the intraspinal structures and on the electrical field potentials generated with epidural spinal cord stimulation. This work, initially pioneered by Sin and Coburn, has successfully been expanded and perfected by Holsheimer and Strujik at the University of Twente, The Netherlands (3-8). The Dutch scientists developed a computerized volume conductor model of the spinal cord to represent in extreme detail the electrical properties of all the intraspinal structures, including the dorsal column and dorsal root fibers. The model can simulate the effects of epidural stimulation with different electrode geometries and configurations (8). The data generated from the model were then validated by comparing them to a large number of data collected by the author in implanted subjects (9-12). The author also conducted a detailed analysis of the clinical properties of the activation of the intraspinal structures at various electrode positions in the spine (13, 14).
Puberty and body composition.

Body composition during puberty is a marker of metabolic changes that occur during this period of growth and maturation, and, thus, holds key information regarding current and future health. During pu
Low Frequency Bending Waves in Periodic Plates

Abstract An asymptotic approximation is obtained for the dispersion relation of flexural waves propagating in an infinite, flat plate, with material properties periodic in one direction. The approximation assumes that the wavelength is long compared with the length of the unit period, but makes no assumption about the magnitude of the variation of material parameters. The leading order term corresponds to an effective plate with areal density equal to the mean and bending stiffnesses which could be predicted from purely static considerations. The first departure from the dispersion relation for an effectively uniform plate depends upon a parameter Ω3, which is discussed in detail. An expression is found for Ω3 for plates with arbitrary periodic variation in material properties. It turns out that Ω3 vanishes for waves travelling normal to the layering if either the areal density or the bending stiffness is uniform throughout the plate. Numerical comparisons of the exact and asymptotic dispersion relations suggest that the cubic term in the dispersion relation is always small.
Strict Joint and Several Liability and Justice

The American tort system regularly conducts a sort of lottery in which plaintiffs try to name as many defendants in a tort action as they can in order to collect a large judgment from at least one of them. This procedure is encouraged under strict joint and several liability, which permits plaintiffs to recover greater damages from defendants – usually businesses – with less moral culpability for the tort than poorer defendants, who bear greater culpability. In a case involving the Disney Corporation and a negligent amusement park rider, for instance, Disney was forced to pay 86% of the court award to the plaintiff, even though the jury found the company to be only 1% liable for the injury. The legal principle of joint and several liability violates morality in several different ways. Even though the principle appears to be better in the short run for plaintiffs, I will show that it fails not only to satisfy utilitarianism, but compensatory justice as well. Hence, the legal principle of joint and several liability should be eliminated in favor of a better, fairer law, which I will briefly sketch at the end.
Structural properties of HIV-1 Env fused with the 14-kDa vaccinia virus envelope protein.

Abstract To gain insights into the structure-function relationship of the envelope ( env ) glycoprotein of the human immunodeficiency virus type 1 (HIV-1) we have generated a vaccinia virus (VV) recombinant (VV-14kENV) that expresses a fusion protein (14k- env ) consisting of the VV 14-kDa envelope protein (110 amino acids) fused at the C-terminus with HIV-1 env protein (816 amino acids). The 14k- env protein displayed unique structural properties in virus-infected cells. This protein was recognized by 14 kDa-specific antisera as well as HIV-1 env antisera. It was not cleaved during virus infection of cultured cells of various origins, it was stable, it was not released to the medium, and it was not incorporated into virions. Instead of a predicted 174-kDa protein, two proteins of about 110 and 100 kDa were observed. The size reduction of the fusion protein was due to limited glycosylation (110 kDa) and formation of unglycosylated protein (100 kDa). The 14k- env protein formed oligomeric structures and was exposed on the cell surface after virus infection. When mice were inoculated with the recombinant virus that expresses the 14K- env fusion protein, humoral immune response against gpl60 was observed. Our findings suggest that 14k- env protein might display novel immunogenic properties.
Naltrexone antagonizes the biobehavioral adaptation to cold water stress in rats.

Abstract The reported studies on the development of tolerance to the analgesic effects of stress have been mostly concerned with the involvement of opioid or non-opioid substances in stress-induced analgesia (SIA). To further investigate the processes involved in SIA tolerance, rats were exposed to forced intermittent cold water swim (ICWS, 18 exposures, 3/min, 10 sec each) on 16 consecutive days. On days 15 and 16, they were injected prior to swim with saline and naltrexone (10 mg/kg), respectively. During swim, three types of readily identifiable behaviors were observed. They may be characterized by immobility and horizontal floating (Type I), intensive activity and escape attemps (Type II), and passivity and “behavioral despair” (Type III). In the acute condition, only Type II and Type III appear in sequence. In the chronic condition, the sequence of behaviors is: Type I, Type II, and Type III. Thirty minutes after swim, analgesia, core temperature, and degree of inactivity were measured. With chronic exposure, tolerance developed to the analgesia, core hypothermia and hypoactivity induced by the ICWS. Type I behavior appeared on day 3 or 4 persisted throughout the chronic treatment. Type II behavior did not adapt. Naltrexone (10 mg/kg) antagonized the adaptive aspect of all those variables where adaptation or tolerance were found (analgesia, hypoactivity, core hypothermia, and Type I behavior) but had no effect on Type II behavior where no adaptation was observed. It is suggested that the endorphins have a functional role in the behavioral and physiological adaptation to aversive stressful environmental situations.
Adaptive local thresholding algorithm that maximizes the contour features within the thresholded image

Global thresholding is widely used in image processing to generate binary images, which are used by various pattern recognition systems. Typically, many features that are present in the original gray-level image are lost in the resulting binary image. This paper presents an adaptive thresholding algorithm, that maximizes the edge features within the gray-level image. The Gaussian pyramid algorithm is used to find the local gray-level variations that are present in the original gray-level image. The resulting Gaussian pyramid image is then subtracted from the original gray-level image removing the local variations in illumination. This new image is then adaptively thresholded using the adaptive contour entropy algorithm. The resulting binary images have been shown to contain more edge features than the binary images generated using global thresholding techniques.
Attempted Isolation of Heavier Group 14 Element Ketone Analogues: Effect of O−H···π-Ar Hydrogen Bonding on Geometry

The terphenyl group 14 element gem-dihydroxy (gem-diol) derivatives Ar2M(OH)2 (Ar = C6H3-2,6-Mes2; Mes = C6H2-2,4,6-Me3), M = Ge (1); Sn (2), were synthesized and characterized by X-ray crystallography, NMR, IR spectroscopy, and combustion analysis. The synthetic route involved treatment of the divalent MAr2 compounds with N2O or Me3NO in hydrocarbon solution. The objective was the isolation of the heavier group 14 element ketone analogues Ar2MO. Despite stringent precautions to exclude moisture and oxygen during the synthesis, the products 1 and 2 were isolated in ca. 30−50% yield. These results are in contrast to the recently reported stabilization of the terphenyl-protected, essentially strain-free, species (bisap)2GeO (bisap = 2,6-di(1‘-naphthyl)phenyl). Seemingly, 1 and 2 represent the addition of H2O to Ar2MO. The identity of the other products is currently unknown. Compound 1 represents the second example of a germanium gem-diol to be structurally characterized, and it features the expected distort...
Ovotestis in a Japanese Medaka

Abstract We observed ovotestis in Japanese medaka Oryzias latipes used to study the effects of bromodichloromethane (BDCM) on gonadal differentiation. Bromodichloromethane, a trihalomethane, is a drinking water disinfection byproduct. Seven-day-old Japanese medaka (n = 30 fish per treatment) were exposed for 10 d to nominal concentrations of BDCM (10 or 25 mg/L) in dimethyl sulfoxide, a carrier solvent control, or a springwater control, then transferred to springwater and reared for 6 months. Ovotestis was present in one female of the 13 Japanese medaka that survived for 6 months after exposure to 10 mg/L BDCM. This is the first report of an intersex condition in a BDCM exposure study. There are no known reports of spontaneous occurrences of ovotestis in Japanese medaka; however, we cannot eliminate the possibility that this single case was spontaneous rather than induced by BDCM. Therefore, further studies with a wide range of concentrations of BDCM are needed to confirm the ovotestis induction potential...
Fermi pseudopotential approximation: Two particles under external confinement

In this paper we calculate the energy levels of two trapped atoms interacting through a spherical two-body potential $V(r)$ under external confinement quantum mechanically. We then replace $V(r)$ by either a regularized energy-independent or an energy-dependent \ensuremath{\delta}-function potential. A comparison shows that the use of an energy-dependent pseudopotential improves significantly upon the use of an energy-independent pseudopotential. The accuracy of the pseudopotential approximation is approximately determined by the ratio ${\ensuremath{\beta}}_{6}{/a}_{\mathrm{ho}},$ where ${\ensuremath{\beta}}_{6}$ and ${a}_{\mathrm{ho}}$ denote the characteristic length scale of the two-body interaction potential $V(r)$ and of the trapping potential, respectively.
Time averaging of multimode optical fiber output for a magneto-optical trap

We demonstrate a method for increasing the amount of power available for laser cooling applications by using a multimode optical fiber. Through randomization of phase shifts of modes within the fiber on time scales faster than the center-of-mass response time of the atoms, a smooth time-averaged trapping beam is generated. The principle has been demonstrated in a pyramidal magneto-optical trap. The method is particularly suitable for the harnessing of the high output power of broad-area diode lasers for laser cooling.
Effect of angle stimulation during development on adult discrimination ability in rats

Hooded rats were reared in very restricted environments with angular, curved, or white-field stimulation. The extent of transfer from this exposure was assessed in adulthood by testing subjects for (a) learning ability in form, brightness, and pattern discrimination tasks, and (b) exploration and activity differences in an open field. The angle-reared group performed better than the other two rearing groups in all three discrimination tasks. Moreover, the curved and white-field groups were equivalent. These learning differences did not appear to result from differences in (a) exploration or activity or (b) dependence on kinesthetic cues. The results demonstrated that one type of early visual stimulation produced transfer to discrimination tasks that varied in difficulty and in degree of relevancy to the rearing forms. This effect was related to the results and interpretations from previous form-rearing studies. Three interpretations were proposed for this transfer and for the advantage of angular vs. curved stimulation.
Identification of DNA sequences unique to virulent type III GBS by subtraction hybridization. |[dagger]| 683

We previously showed that type III group B streptococci (GBS) can be subclassified on the basis of HindIII restriction digest patterns(RDPs) of chromosomal DNA into three RDP types: III-1, III-2 and III-3(Ped. Res. 39: 186A, 1996). Type III-3 strains appear to be more virulent than III-2 or III-1 strains since III-3 strains are significantly more likely to be invasive isolates than are III-2 or III-1 strains. To identify genes unique to III-3 strains, we prepared TaqI digests of chromosomal DNA from representative III-3 and III-2 strains, and subjected the III-3 TaqI digest to successive rounds of subtraction hybridization with the III-2 TaqI digest followed by polymerase chain reaction(PCR) amplification of non-subtracted DNA. Six unique PCR products were derived from the III-3 strain following subtraction hybridization. These were cloned and used to probe chromosomal DNA from six III-2 strains and six III-3 strains by slot-blot hybridization. As expected, all of the cloned subtraction products from the III-3 strain hybridized with the original III-3 strain, while none of the III-3 products hybridized with the six III-2 strains. Three of the III-3 subtraction products hybridized with DNA from all six of the III-3 strains tested, suggesting that these three probes identified genes unique to all III-3 strains. The finding of genes in III-3 strains that are not present in III-2 strains support our contention that HindIII RDP typing identifies genetically related strains of type III GBS. Identification of genes unique to III-3 strains may allow rapid recognition of virulent type III GBS in carriers, and may lead to the characterization of novel genes that contribute to the virulence of type III GBS.