cssi/SciSciGPT-SciSciNet huggingface dataset:
An Ontological Model for Privacy in Emerging Decentralized Healthcare Systems

Emerging healthcare systems are expected to leverage new Internet of Things (IoT) trends to enable preventive and personalized medicine. However, the success of such systems is entirely dependent on the ability to preserve patient privacy. This paper proposes a decentralized ontology based system architecture that caters to a healthcare organization's privacy needs as well as its enterprise security policy concerns considering futuristic IoT and Electronic Health Records (EHR) trends in healthcare. To identify privacy infringements and organizational policy violations across the institution, our proposed HealthCare Security and Privacy (HCSP) ontology is utilized in conjunction with three agent-level filters: the Exception Creation Agent (ECA), the Policy Mapping Agent (PMA), and the Privacy Assurance Filter (PAF). Preliminary evaluation has shown effectiveness of the HCSP ontology in terms of detection of policy compliance to HIPAA standards.
Symposium on Technology Transfer to Developing Countries: Introduction

Technology has played a vital role in improving the economic and social welfare of the poor in developing countries. This symposium is devoted to this subject so that readers may learn more about the methods, types, current status, and constraints involved in these transfers. The reader will quickly realize that many important transfers to developing countries include not only machinery and equipment but also technological capabilities. Technological capabilities are the information and skills ] technical, managerial, and institutional ] that allow productive use of the equipment and technology. At any moment in time, the transfers of technology are in various stages of implementation. Furthermore, these transfers may be occurring concurrently at different levelsrsectors of society. For example, at the national level, usually referred to as the enabling environment, processes may have been enacted to carry out reforms like structural adjustment, privatization, and democracy. At the same time, technologic transfers may be occurring in the education and business sectors involving teacher training and micro lending. The success of these transfers, at any level, usually is determined by the ability of the recipient country to sustain the technology after outside support is removed. Usually a gap is discovered after the technology has been transferred. The gap exists because the enabling environment of the developing country was not the same as the donor’s environment. The challenge to development becomes not the technology itself but the processes involved in closing the gaps. A gap can be caused by the confusion of cultures between recipient and donor countries, firms, and institutions. Each have their own ways
Robust Non-interactive Multiparty Computation Against Constant-Size Collusion

Non-Interactive Multiparty Computations (Beimel et al., Crypto 2014) is a very powerful notion equivalent (under some corruption model) to garbled circuits, Private Simultaneous Messages protocols, and obfuscation. We present robust solutions to the problem of Non-Interactive Multiparty Computation in the computational and information-theoretic models. Our results include the first efficient and robust protocols to compute any function in \(NC^1\) for constant-size collusions, in the information-theoretic setting and in the computational setting, to compute any function in P for constant-size collusions, assuming the existence of one-way functions. Our constructions start from a Private Simultaneous Messages construction (Feige, Killian Naor, STOC 1994 and Ishai, Kushilevitz, ISTCS 1997) and transform it into a Non-Interactive Multiparty Computation for constant-size collusions.
Simultaneous auto-calibration and gradient delays estimation (SAGE) in non-Cartesian parallel MRI using low-rank constraints.

Purpose To correct gradient timing delays in non-Cartesian MRI while simultaneously recovering corruption-free auto-calibration data for parallel imaging, without additional calibration scans. Methods The calibration matrix constructed from multi-channel k-space data should be inherently low-rank. This property is used to construct reconstruction kernels or sensitivity maps. Delays between the gradient hardware across different axes and RF receive chain, which are relatively benign in Cartesian MRI (excluding EPI), lead to trajectory deviations and hence data inconsistencies for non-Cartesian trajectories. These in turn lead to higher rank and corrupted calibration information which hampers the reconstruction. Here, a method named Simultaneous Auto-calibration and Gradient delays Estimation (SAGE) is proposed that estimates the actual k-space trajectory while simultaneously recovering the uncorrupted auto-calibration data. This is done by estimating the gradient delays that result in the lowest rank of the calibration matrix. The Gauss-Newton method is used to solve the non-linear problem. The method is validated in simulations using center-out radial, projection reconstruction and spiral trajectories. Feasibility is demonstrated on phantom and in vivo scans with center-out radial and projection reconstruction trajectories. Results SAGE is able to estimate gradient timing delays with high accuracy at a signal to noise ratio level as low as 5. The method is able to effectively remove artifacts resulting from gradient timing delays and restore image quality in center-out radial, projection reconstruction, and spiral trajectories. Conclusion The low-rank based method introduced simultaneously estimates gradient timing delays and provides accurate auto-calibration data for improved image quality, without any additional calibration scans.
Parity-time symmetric photonics

The establishment of non-Hermitian quantum mechanics (such as parity-time (PT) symmetry) stimulates a paradigmatic shift for studying symmetries of complex potentials. Owing to the convenient manipulation of optical gain and loss in analogy to complex quantum potentials, photonics provides an ideal platform for the visualization of many conceptually striking predictions from non-Hermitian quantum theory. A rapidly developing field has emerged, namely, PT-symmetric photonics, demonstrating intriguing optical phenomena including eigenstate coalescence and spontaneous PT-symmetry breaking. The advance of quantum physics, as the feedback, provides photonics with brand-new paradigms to explore the entire complex permittivity plane for novel optical functionalities. Here, we review recent exciting breakthroughs in PT-symmetric photonics while systematically presenting their underlying principles guided by non-Hermitian symmetries. The potential device applications for optical communication and computing, biochemical sensing and healthcare are also discussed.
Food Photography Is Not an Accurate Measure of Energy Intake in Obese, Pregnant Women.

Background To improve weight management in pregnant women, there is a need to deliver specific, data-based recommendations on energy intake. Objective This cross-sectional study evaluated the accuracy of an electronic reporting method to measure daily energy intake in pregnant women compared with total daily energy expenditure (TDEE). Methods Twenty-three obese [mean ± SEM body mass index (kg/m2): 36.9 ± 1.3] pregnant women (aged 28.3 ±1.1 y) used a smartphone application to capture images of their food selection and plate waste in free-living conditions for ≥6 d in early (13-16 wk) and late (35-37 wk) pregnancy. Energy intake was evaluated by the smartphone application SmartIntake and compared with simultaneous assessment of TDEE obtained by doubly labeled water. Accuracy was defined as reported energy intake compared with TDEE (percentage of TDEE). Ecological momentary assessment prompts were used to enhance data reporting. Two-one-sided t tests for the 2 methods were used to assess equivalency, which was considered significant when accuracy was >80%. Results Energy intake reported by the SmartIntake application was 63.4% ± 2.3% of TDEE measured by doubly labeled water (P = 1.00). Energy intake reported as snacks accounted for 17% ± 2% of reported energy intake. Participants who used their own phones compared with participants who used borrowed phones captured more images (P = 0.04) and had higher accuracy (73% ± 3% compared with 60% ± 3% of TDEE; P = 0.01). Reported energy intake as snacks was significantly associated with the accuracy of SmartIntake (P = 0.03). To improve data quality, excluding erroneous days of likely underreporting (<60% TDEE) improved the accuracy of SmartIntake, yet this was not equivalent to TDEE (-22% ± 1% of TDEE; P = 1.00). Conclusions Energy intake in obese, pregnant women obtained with the use of an electronic reporting method (SmartIntake) does not accurately estimate energy intake compared with doubly labeled water. However, accuracy improves by applying criteria to eliminate erroneous data. Further evaluation of electronic reporting in this population is needed to improve compliance, specifically for reporting frequent intake of small meals. This trial was registered at www.clinicaltrials.gov as NCT01954342.
Optical Flow in Log-mapped Image Plane

In this article we propose a novel approach to compute the optical flow directly on log-mapped images. We propose the use of a generalized dynamic image model (GDIM) based method for computing the optical flow as opposed to the brightness constancy model (BCM) based method. We introduce a new notion of “variable window” and use the space-variant form of gradient operator while computing the spatiotemporal gradient in log-mapped images for a better accuracy and to ensure that the local neighborhood is preserved. We emphasize that the proposed method must be numerically accurate, provides a consistent interpretation and is capable of computing the peripheral motion. Experimental results on both the synthetic and real images have been presented to show the efficacy of the proposed method.
Estimating Life Expectancy at Birth for Mexican Municipalities: An Application of a Regression-Based Technique

Life expectancy is one of the most important indicators of general health. Variations in life expectancy exist among the broad geographic regions in the U.S. as well as among the individual states (Lamb and Siegel 2004; Swanson et al. 2009). The purpose of this study is to estimate life expectancy at birth at the substate level in Mexico. Specifically, a regression-based technique is used to estimate life expectancy at birth at the municipal level according to population size, metropolitan status, and geographical region.
On the Discrimination Between Two Location and Scale Parameter Models

Let xi1, xi2,…, xin, for i=1, 2,…, k, denote independent ran- dome samples of size n each from k distinct populations, the probability density function (pdf) corresponding to the ith population being (l/bi)f[(x-ai)/bi], -∞ 0, where f(x) is a prototype pdf which defines the family of distributions common to the k populations. Let it further be assumed that the location and scale parameters, ai, bi, are unknown and are possibly different for the different populations. Suppose that we are able to assume that f is either one of the two specified families of pdf, f1 and f2. The problem of discrimination reviewed here is that of finding a decision rule which selects one of these two families as the true pdf.
Development of a Protein-based Human Identification Capability from a Single Hair.

Shed human hair (lacking root nuclear DNA) frequently contributes important information to forensic investigations involving human identification. Detection of genetic variation observed in amino acid sequences of hair proteins provides a new suite of identity markers that augment microscopic hair analysis and mitochondrial DNA sequencing. In this study, a new method that completely dissolves single hairs using a combination of heat, ultrasonication, and surfactants was developed. Dissolved proteins were digested and genetically variant peptide (GVP) profiles were obtained for single hairs (25 mm) via high-resolution nanoflow liquid chromatography-based mass spectrometry and a novel exome-driven bioinformatic approach. Overall, 6519 unique peptides were identified and a total of 57 GVPs were confirmed. Random match probabilities ranged between 2.6 x 10-2 and 6.0 x 10-9 . The new bioinformatic strategy and ability to analyze GVPs in forensically relevant samples sizes demonstrate applicability of this approach to distinguish individuals in forensic contexts.
CEO Network and CEO Turnover

This paper analyzes the aggregate properties of the network formed by chief executive officers (CEOs), measures individual position on this network, and explores its relation to CEO turnover and new CEO selection. I find that individual connectedness matters, more so in the choice of a new CEO, but also in whether a CEO departs from a current job. Connnectedness makes CEOs more likely to depart from their current positions. Outside CEO hires are likely to be well connected. New CEOs with central network positions receive significantly higher levels of compensation. Firms that hire well-connected new CEOs tend to be bigger, have more board members and higher proportion of outside directors. The results show no evidence that there are relations between the firm performance change surrounding turnover incidences and the incumbent or successor CEO's network position.
OWASP Risk Analysis Driven Security Requirements Specification for Secure Android Mobile Software Development

The security threats to mobile applications are growing explosively. Mobile apps flaws and security defects open doors for hackers to break in and access sensitive information. Defensive requirements analysis should be an integral part of secure mobile SDLC. Developers need to consider the information confidentiality and data integrity, to verify the security early in the development lifecycle rather than fixing the security holes after attacking and data leaks take place. Early eliminating known security vulnerabilities will help developers increase the security of apps and reduce the likelihood of exploitation. However, many software developers lack the necessary security knowledge and skills at the development stage, and that's why Secure Mobile Software Development education is very necessary for mobile software engineers. In this paper, we propose a guided security requirement analysis based on OWASP Mobile Top ten security risk recommendations for Android mobile software development and its traceability of the developmental controls in SDLC. Building secure apps immune to the OWASP Mobile Top ten risks would be an effective approach to provide very useful mobile security guidelines.
Group-based physical activity trajectories in children transitioning from elementary to high school

Physical activity has been observed repeatedly to decline as children transition into adolescence; however, few studies have explored the possibility that sub-groups of children experience unique patterns of change during this transition. The purpose of this longitudinal study was to examine the physical activity trajectories in clusters of youth transitioning from 5th to 11th grade. Participants (n = 652) were recruited as 5th graders (ages 10–12 years) from elementary schools (n = 21) in two school districts. Demographic, anthropometric, and physical activity data were collected once per year when children were in 5th, 6th, 7th, 9th, and 11th grades. Children wore accelerometers for 7 consecutive days. Group-based trajectory modeling statistical techniques were applied to identify patterns of physical activity trajectories. Posterior probabilities confirmed participants’ membership in their respective group. Three distinct physical activity trajectories were identified. Group 1 (n = 27) remained highly active over time, and physical activity increased from ages 14 to 16 years. Group 2 (n = 365) was active at baseline, but activity declined and remained low as group members aged. Group 3 (n = 260) had the lowest levels of physical activity at all ages, and activity declined from ages 10 to 16 years. While most children experienced a decline in physical activity as they transitioned into high school, some remained highly active and increased their level of physical activity. Future studies should test physical activity interventions for youth that are tailored for age-related trajectory groups.
Predicting seizure freedom after epilepsy surgery, a challenge in clinical practice.

Abstract Objective The objective of this study was to compare the accuracy of clinical judgment in predicting seizure outcome after resective epilepsy surgery relative to two recently published statistical tools [the Epilepsy Surgery Nomogram (ESN) and the modified Seizure-Freedom score (m-SFS)]. Methods Details of presurgical evaluations of 20 patients who underwent epilepsy surgery were presented to 20 epilepsy experts. The final surgical treatment was also disclosed. The clinicians were asked to predict the likelihood of a good outcome (Engel 1) at 2 and 5 years in each case. The ESN and the m-SFS predictions were calculated with the data provided to the clinicians. The discriminative ability of clinical judgment, ESN, and m-SFS was assessed by calculating a concordance index (C-index). Expert opinion, the m-SFS and the ESN performances were compared using a Receiver Operating Characteristic (ROC) curve analysis. Results The mean age at surgery was 29 years (standard deviation [SD] = 14); 40% were male; 70% were right-handed, and thirteen (65%) had an Engel outcome 1 at 2 and 5 years. The mean C-index for the mean physician's prediction was 0.478 with a variance of 0.012. The ESN had an area under the curve (AUC) of 0.528 and 0.533 for the 2-year and 5-year predictions in comparison with the clinicians' predictions that was 0.476, and 0.466, respectively. For the m-SFS, the AUC at 2 years and 5 years was 0.539 and 0.539, respectively. No statistical difference was noted between the ESN and the clinicians or between m-SFS and the ESN, but there is a moderate statistical difference favoring the m-SFS to the clinicians (p 0.0960 and 0.0514, for 2 and 5 years). Significance Clinical judgment was not superior to the ESN nor to the m-SFS. Together with the interphysician's prediction variability, our findings reinforce the need for better tools to predict postoperative outcomes.
Gopher Tortoise (Gopherus polyphemus) Gut Passage Can Alter Seed Germinability

Seed dispersal by animals is an important plant-animal mutualism, but saurochory, the dispersal of seeds by reptiles, is an understudied phenomenon despite its prevalence in many taxa. The effects of seed ingestion by the gopher tortoise (Gopherus polyphemus) were investigated in eight central Florida plant species by comparing germination of ingested seeds to seeds that did not pass through tortoises. Seeds from both treatments were also planted with and without tortoise scat. Both the percentage of seeds germinating and the time to germination were recorded. Ingested seeds from two fleshy-fruited plant species germinated in greater proportions and in less time than control seeds. The presence of scat also increased germination proportion following gut passage and decreased time to germination in both these species. Germination proportions in five dry-fruited native species were either not affected, or lowered, and time to germination was either not affected, or slower. Similarly, the effects of scat had either no effect on germination percentage in these species or caused a decrease, and either had no effect on time to germination or caused an increase. One non-native dry-fruited species was also tested, and although germination percentage following gut passage was unaffected, time to germination decreased. Similarly, while the addition of scat increased germination percentage, there was no effect on time to germination. In summary only seeds from fleshy-fruited plant species were consistently positively impacted by passage through gopher tortoise guts and by gopher tortoise scat.
New developments in diversity and inclusiveness in geosciences

It has been 12 years since the Journal of Geoscience Education published a special issue on broadening participation in the Earth sciences (Riggs & Alexander, 2007). There have been a number of maj...
Impact of Obesity in Patients with Candida Bloodstream Infections: A Retrospective Cohort Study.

Candida species are responsible for 15% of bloodstream infections, leading to prolonged hospitalizations and increased mortality. With the rise in obesity, antifungal dosing is unclear. The purpose of this study was to determine differences in clinical outcomes between obese versus non-obese patients with Candida bloodstream infections. This retrospective cohort included adult patient’s first episode of Candida bloodstream infection treated with ≥ 48 h of antifungal therapy between 1 June 2013 and 31 August 2019. Patients were excluded for: dual systemic antifungal therapy, polymicrobial infections, or chronic candidiasis. The primary outcome was infection-related length of stay. Secondary outcomes included: time to candidemia resolution, 30-day readmission rates, and in-hospital mortality. Eighty patients were included (28 obese; 52 non-obese). Most were male (55%); median age was 54 years. Median BMI and weight were 36.3 kg/m2 and 103 kg versus 20.4 kg/m2 and 61 kg, respectively (p < 0.01). Baseline characteristics were comparable. C. albicans was isolated in 37.5% of cultures and C. glabrata in 30%. Micafungin was utilized empirically in 72.5% of patients; obese patients received definitive micafungin more frequently (57.1% vs. 21.2%; p < 0.01) and were treated longer (13 versus 10 days; p = 0.04). Infection-related length of stay was 19 days in the obese patients and 13 days in the non-obese patients (p = 0.05). Non-obese patients had a shorter duration of candidemia (5 versus 6 days; p = 0.02). In-hospital mortality was numerically higher in obese patients (21.4% versus 13.5%; p = 0.36). There were no differences in 30-day readmissions between groups. Worse clinical outcomes were observed for obese versus non-obese patients. Further clinical research is warranted.
Selection for Liver Transplantation: Indications and Evaluation.

Liver transplantation is an important therapeutic option for patients with life-limiting liver disease, which may present in the form of acute liver failure, end-stage chronic liver disease, primary hepatic cancers, or inborn metabolic disorders. While significant strides have been made with respect to liver transplantation outcomes, the practice is constrained by an organ supply/demand mismatch. The purpose of this review, therefore, is to review the general indications and contraindication to liver transplantation, and to provide an overview of the transplant evaluation process. These considerations ultimately shape the specific criteria for patient selection, which will continue to evolve as means are developed to expand the donor pool, improve surgical techniques, broaden indications for safe transplant, and extend the lifetime of a graft. Selected patients with unresectable hilar cholangiocarcinoma may be candidates for liver transplantation. Patients over 65 years may be transplant candidates if they possess a favorable comorbidity profile. Patients at body mass index extremes (≥ 40 or < 18.5) have increased post-transplant mortality and require nutritional evaluation. Liver transplantation may be life saving for patients with acute liver failure or end-stage liver disease. It is therefore critical for healthcare providers caring for patients with liver disease to be familiar with the general indications for transplantation and to know when it is appropriate or inappropriate to refer for transplant evaluation.
Edge detection based on dielectric metasurfaces

Optical analog signal processing technology has been widely studied and applied in a variety of science and engineering fields. It overcomes the low-speed and high-power consumption disadvantages compared with its digital counterparts. One kind of the optical analog signal processing, optical edge detection, is a useful method for characterizing boundaries. In another context, metasurface as a recently developed technology has been introduced to optical imaging and processing and attracted much attentions. Here, we propose a new mechanism to implement an optical spatial differentiator consisting of a designed Pancharatnam-Berry (PB) phase metasurface inserted between two orthogonally aligned linear polarizers. Unlike other spatial differentiator approaches, our method does not depend on complex layered structures or critical plasmonic coupling condition, but instead based on spin-to-orbit interactions. Experiment confirms that broadband optical analog computing enables the edge detection of an object and achieves tunable resolution at the resultant edges. Furthermore, metasurface orientation dependent edge detection is also demonstrated experimentally.
Minimally important difference in cost savings: Is it possible to identify an MID for cost savings?

As healthcare costs continue to increase, studies assessing costs are becoming increasingly common, but researchers planning for studies that measure costs differences (savings) encounter a lack of literature or consensus among researchers on what constitutes “small” or “large” cost savings for common measures of resource use. Other fields of research have developed approaches to solve this type of problem. Researchers measuring improvement in quality of life or clinical assessments have defined minimally important differences (MID) which are then used to define magnitudes when planning studies. Also, studies that measure cost effectiveness use benchmarks, such as cost/QALY, but do not provide benchmarks for cost differences. In a review of the literature, we found no publications identifying indicators of magnitude for costs. However, the literature describes three approaches used to identify minimally important outcome differences: (1) anchor-based, (2) distribution-based, and (3) a consensus-based Delphi methods. In this exploratory study, we used these three approaches to derive MID for two types of resource measures common in costing studies for: (1) hospital admissions (high cost); and (2) clinic visits (low cost). We used data from two (unpublished) studies to implement the MID estimation. Because the distributional characteristics of cost measures may require substantial samples, we performed power analyses on all our estimates to illustrate the effect that the definitions of “small” and “large” costs may be expected to have on power and sample size requirements for studies. The anchor-based method, while logical and simple to implement, may be of limited value in cases where it is difficult to identify appropriate anchors. We observed some commonalities and differences for the distribution and consensus-based approaches, which require further examination. We recommend that in cases where acceptable anchors are not available, both the Delphi and the distribution-method of MID for costs be explored for convergence.
Skeletal Manifestations of Heritable Disproportionate Dwarfism in Cats as Determined by Radiography and Magnetic Resonance Imaging.

Objective The aim of this study was to characterize the radiographic alignment of thoracic and pelvic limbs and evaluate for intervertebral disc disease in cats with feline disproportionate dwarfism (FDD). Study Design Observational cross-sectional study. Radiographic joint orientation angles were measured in 10 thoracic and pelvic limbs from 5 FDD cats and compared with those angles measured in 24 thoracic limbs and 100 pelvic limbs from skeletally normal cats. Magnetic resonance imaging of the spine was performed in 2 FDD cats for the evaluation of pathology of the intervertebral discs or vertebrae. Results All limbs from FDD cats possessed deformities. FDD humeri demonstrated procurvatum proximally, and recurvatum distally in the sagittal plane, but showed no difference in the frontal plane. FDD radii possessed excessive recurvatum proximally, and procurvatum distally in the sagittal plane, and varus proximally and valgus distally in the frontal plane. Whereas no torsion was discernible in the humeri, all radii had external torsion. In the frontal plane, FDD femurs exhibited varus both proximally and distally whereas the tibia possessed proximal valgus and distal varus. No torsion in the pelvic limbs was observed. No spinal pathology was detected in the FDD cats included in the original study. Conclusion Feline disproportionate dwarfism results in significant appendicular deformity in all limbs. The incidence of intervertebral disc degeneration in FDD cats is inconclusive.
On the Minimization of Non-Linear Age of Information in the Internet of Things

In this paper, a novel centralized resource allocation scheme is proposed to enable a wireless base station to adapt to heterogeneous Internet of Things (IoT) environments and manage scarce communication resources to ensure timely delivery of IoT device data. In the considered system, the timeliness of information is determined using non-linear age of information (AoI) metrics that can naturally quantify the freshness of information. To capture the inherent heterogeneity of the IoT system, non-linear aging functions are proposed and designed specifically for IoT devices having different types of messages. To minimize AoI, the proposed centralized scheme allocates the limited communication resources considering AoI and enables the base station to learn the device types. Furthermore, the proposed centralized resource management scheme with different activation probabilities, outage probabilities, and heterogeneity levels is analyzed in terms of the average instantaneous AoI. Simulation results show that the proposed centralized allocation scheme effectively decreases the average instantaneous AoI in a massive IoT with high outage probability and high heterogeneity.
Culture, Biology, and Evolution: The Mead–Freeman Controversy Revisited

Derek Freeman argues that the central issue in the Mead–Freeman controversy is evolution. He views Margaret Mead's Coming of Age in Samoa as not only misleading about Samoa but as a “sacred text” that promoted an antievolutionary paradigm among American cultural anthropologists. A review of Mead's writing on culture, biology, and evolution demonstrates that contrary to Freeman's claim, Mead favored an evolutionary approach throughout her career. Moreover, while Mead's book was a popular text and a bestseller, it was not a “sacred text” among anthropologists. Freeman's misrepresentation of the historical record concerning Mead's views and the place of Coming of Age in anthropology raises major questions about his scholarship.
Central Chemosensitivity in Mammals

More than a century has passed since the beginning of direct experimentation on control of ventilation, and the ensuing years have brought considerable insight into the mechanisms of this control. Much of what we know about cellular chemosensitivity in mammals comes from a limited number of species; yet, given the diversity of circumstances in which mammals exist, their potential has been greatly underused. Here we review some of the environmental situations for plasticity of mammalian central chemosensitivity and function of chemosensors. “Normal” breathing patterns change during sleep, hibernation, and exercise, and central chemosensitivity must be altered during acclimation or adaptation to altitude, burrowing, or disease states. Where central chemosensitive cells are located, and what qualifies a cell as chemosensitive, is currently debated. The chemosensitivity of these cells changes over development, and the signaling mechanisms of these cells vary between chemosensitive regions, probably accounting for plasticity in response to environmental perturbations.
Nucleosomes: Structure and Function

The structure of the nucleosome core particle, the basic repeating unit in eukaryotic chromatin, allows us to view the role of histones in regulating transcription, and in assembling specialized chromatin domains in a structural context. The organization of eukaryotic DNA into chromatin has fundamental implications for our understanding of all cellular processes that use DNA as a substrate. Keywords: histone; nucleosome; chromatin; DNA; crystal structure; transcription regulation
Magnetic field effects on float-zone Si crystal growth: III. Strong axial fields

Abstract Axial magnetic fields ranging in strength up to 5000 G have been applied during the float-zone growth of dislocation-free Ga-doped 〈100〉 silicon crystals. All crystals were grown at a pull rate of 4 mm/min with rotation rates from 12 to 0 rpm. Evaluation by spreading resistance showed a marked reduction in the dopant concentration fluctuations for certain growth conditions in axial fields greater than 3000 G. However, in the strong fields the growth axis of the crystals wandered randomly and made such crystals very difficult to grow, especially as the rotation rate was reduced. A crystal growth without rotation in a 5000 G field gave the most uniform doping but only in a central “core” region extending over about one third of the crystal diameter.
A Perspective on Nonstationarity and Water Management1

This essay offers some perspectives on climate-related nonstationarity and water resources. Hydrol- ogists must not lose sight of the many sources of nonstationarity, recognizing that many of them may be of much greater magnitude than those that may arise from climate change. It is paradoxical that statistical and deterministic approaches give us better insights about changes in mean conditions than about the tails of proba- bility distributions, and yet the tails are very important to water management. Another paradox is that it is dif- ficult to distinguish between long-term hydrologic persistence and trend. Using very long hydrologic records is helpful in mitigating this problem, but does not guarantee success. Empirical approaches, using long-term hydrologic records, should be an important part of the portfolio of research being applied to understand the hydrologic response to climate change. An example presented here shows very mixed results for trends in the size of the annual floods, with some strong clusters of positive trends and a strong cluster of negative trends. The potential for nonstationarity highlights the importance of the continuity of hydrologic records, the need for repeated analysis of the data as the time series grow, and the need for a well-trained cadre of scientists and engineers, ready to interpret the data and use those analyses to help adjust the management of our water resources.
Fatty Acid Composition of Unicellular Strains of Blue-Green Algae

The fatty acids of 34 strains of unicellular blue-green algae provisionally assigned to the genera Synechococcus, Aphanocapsa, Gloeocapsa, Microcystis, and Chlorogloea by Stanier et al. have been chemically characterized. The strains analyzed can be divided into a series of compositional groups based upon the highest degree of unsaturation of the major cellular fatty acids. Twenty strains fall into the group characterized by one trienoic fatty acid isomer (alpha-linolenic acid), and seven strains fall into a group characterized by another trienoic acid isomer (gamma-linolenic acid). These groups in many cases correlate well with groupings based upon other phenotypic characters of the strains, e.g., deoxyribonucleic acid base composition. The assignment of a strain to a compositional group is not altered when the strain is grown under a variety of different culture conditions. All strains contain glycolipids with the properties of mono- and digalactosyldiglycerides.
ICE AGE INITIATION BY AN OCEAN-ATMOSPHERIC CIRCULATION CHANGE IN THE LABRADOR SEA

Abstract The contrast between the large Greenland ice sheet and the nearly ice-free area of Canada to the west exemplifies the critical role of the moisture supply in glaciation. The trigger for new ice-sheet growth in Canada at the end of the last interglacial was probably an increase in the moisture supply rather than regional cooling. Triggering is attributed to stronger storm activity in the Labrador-Baffin area, caused by warming in the Labrador Sea and cooling in the Greenland-Norwegian Sea. The key to this temperature and circulation change may have been an increase in the hydrologic deficit of the Mediterranean Sea. A larger hydrologic deficit would have increased Mediterranean salinity and, consequently, the volume of Mediterranean Overflow Water. A resulting increased upwelling of Mediterranean Overflow Water from the lower thermocline off Scotland would have diverted additional warm North Atlantic Drift water westward via the Irminger Current, thus warming the Labrador Sea. The underlying cause of the hydrologic deficit increase was diminishing Milankovitch summer insolation in lower latitudes. This reduced African monsoon intensity and Nile River discharge. In modern times nearly all Nile discharge to the Mediterranean has been lost due to irrigation practices, culminating with the completion of the Aswan High Dam in 1968. The total increase in the hydrologic deficit due to Nile discharge loss is now 8%. In the next 70–100 years the Nile loss, added to larger evaporative losses due to CO 2 warming, may increase the deficit as much as 22% above the inferred deficit at the beginning of the last glaciation thus further warming the Labrador Sea. Consequently, the triggering of major ice-sheet growth in Canada ∼ 100 years from now is possible.
Early effects of excess cadmium uptake in Phaseolus vulgaris

Abstract. Seedlings of Phaseolus vulgaris were exposed to solutions containing Cd2+ in the range 0 to 1 molm−3. Ethylene formation started following 3 h of exposure to 10−2, 10−1 and 1 mol m−3 Cd2+, peaked at 18 h and returned to a relatively low rate after 24 h. Cadmium-induced ethylene formation depended on the formation of 1-aminocyclopropane-1-carboxylic acid (ACC). Aminoethoxyvinylglycine (AVG, 0.1 mol m−3) inhibited ACC accumulation and ethylene production during exposure to 0.2 mol m−3 Cd2+. Activity of soluble and ionically-bound peroxidase increased after 18 h of exposure to Cd2+ concentrations above 10−3 mol m−3 due to an increase in activity of cathodic isoperoxidases. Stimulation of soluble and ionically-bound peroxidase by 0.2 mol m−3 Cd2+ was reduced in the presence of 0.1 mol m−3 AVG. Accumulation of soluble and insoluble (‘ligninlike’) phenolics was found in plants exposed to Cd2+ (10−2 mol m−3 or above) in the presence or absence of AVG. Deposition of insoluble (autofluorescing) material occurred in cell walls around vessels and was associated with reduced expansion and water content of leaves.
A refractory inclusion in the Kaba CV3 chondrite: some implications for the origin of spinel-rich objects in chondrites

The first detailed petrographic and mineralogical study of a Ca, Al-rich inclusion (CAI) from the Kaba CV3 chondrite is reported. This 'fine-grained' CAI contains abundant small, rounded, rimmed, spinel-rich objects which have important features in common with the spinel-rich objects in other carbonaceous and ordinary chondrites. These nodules are interpreted as fractionated distillation residues of primitive dust. However, the available data do not unambiguously rule out a condensation origin for at least some of these objects. Finally, the preservation of distinct diopside-hedenbergite rims on the spinel-rich bodies and the small grain size of many minerals in the CAI matrix material both suggest that the CAI accreted cool and had a relatively cool thermal history in the Kaba parent body.
Nature’s Experiments, Society’s Closures

The Wild Child, who lives through much of childhood without exposure to language or culture, is exceedingly rare. I examine three of the most famous and most well authenticated cases: Helen Keller, who was isolated from eighteen months until her seventh year; ‘Victor’, the wild boy of the forest near Aveyron, whom Itard studied; and ‘Genie,’ who was isolated from language from age two until the middle of her thirteenth year. Attention is paid both to the development of these individuals and to the conduct and misconceptions of those who examined and trained them. Various morals are drawn, which might also have application to research on non-human primates.
Learning computer programming through dynamic representation of computer functioning: evaluation of a new learning package for Pascal

Abstract This paper describes and evaluates a new approach to teaching the beginning Pascal programming course at Worcester Polytechnic Institute. At the heart of this approach is a new computer learning package, called PASLAB, which allows students to understand what is happening inside the computer relative to statements in Pascal programs constructed by an expert. There were 322 students participating in the evaluation under traditional conditions in 1984, and 296 students participating under the new conditions in 1985. Comparison between the two groups was made by examining the respective regression equations predicting final grade for each set of students. While the characteristics of both sets of students were very similar, the regression equations were markedly different. Under traditional conditions, background characteristics of students, including programming experience, had a major impact on the grades those students received. With Paslab in place, the impact of those background characteristics decreased while the importance of psychological orientations (motivation) increased. There were no differences in performance with respect to gender. Further research is needed to test the impact of Paslab in non-technical institutions. The positive results of this study suggest the fruitfulness of developing additional computer learning packages on the same principles as Paslab to be used in other computer-science courses as well as in other fileds.
Pointing into remote 3D environments

In anticipation of the proliferation of micro-projectors on our handheld imaging devices, we designed and tested a camera-projector system that allows a distant user to point into a remote 3D environment with a projector. The solution involves a means for locating a projected dot, and for adjusting its location to correspond to a position indicted a remote user viewing the scene through a camera. It was designed to operate efficiently, even in the presence of camera noise. While many camera-projector display systems require a calibration phase, the presented approach allows calibration-free operation. The tracking algorithm is implemented with a modified 2D gradient decent method that performs even in the presence of spatial discontinuities. Our prototype was constructed using a standard web-camera and network to perform real-time tracking, navigating the projected dot across irregularly shaped and colored surfaces accurately. Our tests included a camera-projector system and client on either side of the Atlantic Ocean with no loss of responsiveness.
Effects of Chrysaora quinquecirrha (Sea nettle) toxin on sodium transport across frog skin.

Sea nettle toxin was found to increase the short-circuit current across isolated frog skin. This effect was blocked by hyperimmune serum but not by calcium chloride. In vitro guinea pig kidney (Na + K) ATPase was unaffected by the toxin. The rise in short-circuit current was mimicked by vasopressin but tissue level of 3'5' cyclic AMP were not found to be elevated over controls.
Topologically driven swelling of a polymer loop

Numerical studies of the average size of trivially knotted polymer loops with no excluded volume were undertaken. Topology was identified by Alexander and Vassiliev degree 2 invariants. Probability of a trivial knot, average gyration radius, and probability density distributions as functions of gyration radius were generated for loops of up to N = 3,000 segments. Gyration radii of trivially knotted loops were found to follow a power law similar to that of self-avoiding walks consistent with earlier theoretical predictions.
Involvement of NF-AT in type I human T-cell leukemia virus tax-mediated fas ligand promoter transactivation

Human T-cell leukemia virus type I (HTLV-I)-infected T-cells constitutively express surface Fas ligand (FasL), which may serve as a mechanism of viral pathogenesis. HTLV-I induces transcription of FasL gene through the viral transactivator Tax, although the underlying molecular mechanism remains unclear. In the present study, we have analyzed both the cis-activating element and transactivating factors involved in Tax activation of the FasL promoter. We show that the 486-base pair upstream region of the human FasL gene is sufficient for Tax-mediated transactivation in Jurkat T-cells. Interestingly, a palindromic DNA sequence (GGAAACTTCC) covering the consensus NF-ATp binding site (GGAAA), is required for Tax activation of FasL promoter. The involvement of NF-AT in this transactivation event is suggested by the finding that Tax fails to activate the FasL promoter in a Jurkat T-cell line defective in capacitative calcium entry, a signaling mechanism involved in NF-AT activation. Furthermore, activation of FasL promoter by Tax is largely attenuated in the nonlymphoid F9 embryonal and COS kidney cells deficient in NF-ATp expression. DNA-protein interaction assays reveal that the NF-AT-like motif in the FasL promoter is bound by both NF-ATp and NF-AT4 in Jurkat T-cells expressing Tax. The binding of NF-ATp, although not NF-AT4, to this enhancer also occurs along with HTLV-I-mediated infection of human peripheral blood T-cells. Furthermore, exogenously transfected NF-ATp binds to the NF-AT-like enhancer and participates in Tax-mediated FasL promoter transactivation. These results suggest an important role for proteins of the NF-AT family in HTLV-I Tax-mediated FasL gene transactivation.
WOMEN AND THE PUBLIC DRINKING PLACE: A CASE STUDY OF ADO‐EKITI, NIGERIA

This paper uses the bars of Ado-Ekiti as a site to explore the use of urban space by women and men. Ado-Ekiti is a Yoruba city of 150,000 people in southwestern Nigeria. Feminist and political economy perspectives are used in developing the three-part theme of the way that gender intersects with the relations between bars and production, bars and reproduction, and bars and consumption. A look at the history of alcohol in Nigeria and of Yoruba women as traders and their cultural role provides context. Survey results and personal observations connect empirical findings to the tripartite theme. Women own and run three fourths of Ado-Ekiti's two hundred plus bars, but men control the upscale bars. Many of Ado's female bar owners are on the receiving end of an exploitative relationship with the global economy via the brewing industry, in a patriarchal society that assigns them a heavy reproductive burden.