cssi/SciSciGPT-SciSciNet huggingface dataset:
A 2500 year sediment record from Fayetteville Green Lake, New York: evidence for anthropogenic impacts and historic isotope shift

A series (N = 12) of short (< 1 m) sediment cores were collected from meromictic Green Lake in Fayetteville, New York to investigate potential anthropogenic impacts on the watershed during historic time and environmental change over the past ~ 2,500 years. Stratigraphic data document an abrupt basinwide change during the early 1800's A.D. from brown laminated sediments to grey varved sediments separated by a transition zone rich in aquatic moss. Deforestation of the region by European settlers during the early 1800's A.D. resulted in a flux of nutrients and increased biological productivity followed by a 7‐fold increase in sediment accumulation rates. Elemental geochemical data document the anthropogenic loading of lead to the to the lake basin via atmospheric fallout. Stable oxygen isotope (δ18O calcite) data also provide evidence for an abrupt shift in the isotopic composition of lake water ~ 150–200 years ago. This isotopic shift could have been a local phenomenon related to an increased supply of summer enriched precipitation following removal of forest vegetation, or it might have reflected broader scale climatic changes. We hypothesize that the δ18O calcite shift was the result of the polar front jet stream migrating from a more southerly prehistoric position to a contracted, northerly configuration ~ 150–200 years ago. Such a shift could have been natural, associated with the end of the Little Ice Age or it may have been anthropogenically forced.
"The eye sees only what the mind is prepared to comprehend": Unrecognized incidental findings on intraoperative computed tomography during spine instrumentation surgery.

Abstract Background Intraoperative computed tomography (CT) is becoming more widely utilized in spine fusion surgeries. The use of CT-based image guidance has been shown to increase the accuracy in instrumentation placement and to reduce the rate of reoperation. However, incidental findings that are obvious in retrospect are still missed in spinal fusion surgeries due to the concept of inattentional blindness and surgeons' preoccupation with the main objective of intraoperative CT (i.e. instrumentation accuracy). Case description The first case describes a 60-year-old male who underwent posterior spinal laminectomy and interbody fusions from L2-L5. Intraoperative CT confirmed appropriate placement of hardware. However, when he was transferred out to the care unit and extubated, he developed a severe headache for which the source was confirmed to be a pneumocephalus from durotomy and cerebrospinal fluid leakage on repeat CT. A retrospective review of his intraoperative CT demonstrated the intrathecal air at L5-S1 interlaminar space that was missed on evaluation during surgery. The second case describes a 68-year-old female who was treated with a successful T4 to pelvis instrumentation and fusion with vertebral column resection at T10 confirmed with imaging. Postoperatively, she developed rapidly progressive oxygen desaturation and was found to have a pneumothorax which had been present on the intraoperative imaging. Conclusion This case report of two patients with missed intraoperative findings demonstrates the importance of looking beyond instrumentation placement and evaluating the entire intraoperative CT imaging to find abnormalities that could complicate the patients' postoperative recovery and overall hospital stay.
The evolution of yield loci with finite plastic deformation along proportional and non-proportional loading paths in an annealed extruded AZ31 magnesium alloy

Abstract This investigation reports for the first time, the subsequent yield loci after finite plastic deformation based on 10μe offset definition yield of an annealed extruded AZ31 magnesium alloy under proportional and non-proportional loading paths. The proportional loading paths comprise uniaxial tension, free end torsion, and combined tension-torsion radial paths. The tension loading followed by torsion, and torsion followed by tension are the non-proportional loading paths. Subsequent yield loci under proportional loading paths show a prominent nose in the loading direction and are almost flat in the unloading direction with evolution of significant isotropic hardening under tension and visible kinematic hardening under torsion loading path. Strong path-dependency is observed in subsequent yield loci under non-proportional loading directions along with hardening effects. All the yield loci are investigated in tension-torsion (σ₁₁-√3σ₁₂) stress space. The results are significantly different than observed for other metals, especially for aluminum alloys by Khan et al. (2009) and Iftikhar et al. (2021). Elastic moduli within each subsequent yield loci are also measured during these experiments with the increase in plastic strain. The observed small decreases in the elastic moduli with increasing plastic strains are very similar to the ones reported earlier (Iftikhar et al., 2021; Khan et al., 2009).
The FDA's Misplaced Priorities: Premarket Review Under the Family Smoking Prevention and Tobacco Control Act

Among other key objectives, the 2009 Family Smoking Prevention and Tobacco Control Act was designed to end an era of constant product manipulation by the tobacco industry that had led to more addictive and attractive products. The law requires new tobacco products to undergo premarket review by the U.S. Food and Drug Administration (FDA) before they can be sold. To assess the FDA’s implementation of its premarket review authorities, we reviewed FDA actions on new product applications, publicly available data on industry applications to market new products, and related FDA guidance documents and public statements. We conclude that the FDA has not implemented the premarket review process in a manner that prioritizes the protection of public health. In particular, the FDA has: (1) prioritized the review of premarket applications that allow for the introduction of new tobacco products over the review of potentially noncompliant products that are already on the market; (2) misallocated resources by accommodating the industry’s repeated submissions of deficient premarket applications; and (3) weakened the premarket review process by allowing the tobacco industry to market new and modified products that have not completed the required review process.
Three-Axis Capacitive Sensor Arrays for Local and Global Shear Force Detection

We report the real time characterization and measurement results of a new tri-axial capacitive sensing array. Each unit cell of the Kapton based sensor has an overlapping electrode geometry that allows for the measurement of normal and shear force magnitudes, and the estimation of the 2D and 3D angle of the shear force. The use of a patterned Ecoflex dielectric layer further improves the shear force response and the tunability of the sensor. A custom readout circuit was developed to selectively read the differential capacitances in the sensor array. The local (unit cell) and global (array) force response of the sensor was characterized using a tilt stage, allowing us to determine both the normal and the shear response at different angles in the range of 0-20N. The results show that the Unit Cell response is uniform in the linear range of 0-10N for normal forces (4.6fF/N for all four differential capacitances) and shows good sensitivity for shear forces (1.4 fF/N difference between the right and left differential capacitances at the minimum) and low cross talk. Similar results were seen when a global force was applied across the sensor array. 2D and 3D models were developed to extrapolate the shear force angle from the capacitance data. We also characterized the flexible patterned dielectric layer to understand the effect of its structural dimensions on the effective relative permittivity and developed an analytical model to easily calculate the effective relative permittivity, which showed excellent correlation with the experimentally obtained results. [2020-0382]
Link Prediction Techniques for Opportunistic Networks Using Machine Learning

The scope of implementing Machine Learning techniques in other technologies is increasing day-by-day. The researchers of Machine Learning make it popular in almost every domain of real-life. Nowadays, most of the researchers are is adding machine learning-based techniques into their area of interest to craft its better version. Opportunistic Network (OppNet) is not an exception in this scenario. A recent survey reveals the fact that the performance of an Opportunistic Network can be enhanced with the fusion of Machine Learning Techniques into it especially in Link prediction. Some researchers in recent times successfully implemented these types of experiments. This paper presents the popular Machine Learning Techniques that can be implemented in Opportunistic Networks for better performance. It is believed that this paper will help upcoming researchers to choose suitable Machine Learning based Technique in Opportunistic Networks as per their requirements.
Altered amygdala-cortical connectivity in individuals with Cannabis use disorder.

Background Cannabis is one of the most commonly used substances in the United States. Prior literature using task-based functional magnetic resonance imaging (fMRI) has identified that individuals with Cannabis use disorder (CUD) show impairments in emotion processing circuitry. However, whether the functional networks involving these regions are also altered in CUD remains poorly understood. Aims Investigate changes in resting-state functional connectivity (rsFC) in regions related to emotional processing in CUD. Methods Sixty-two participants completed resting-state fMRI, including 21 with CUD, 20 with histories of illicit substance use but no current CUD diagnosis, and 21 with no history of illicit substance use. Whole-brain seed-based connectivity analyses were performed and one-way analyses of covariance (ANCOVAs) were conducted to detect group differences in the bilateral amygdalae, hippocampi, and the anterior and posterior cingulate cortices. Results The CUD group exhibited significant reductions in rsFC between the amygdala and the cuneus, paracentral lobule, and supplementary motor area, and between the cingulate cortices and the occipital and temporal lobes. There were no significant group differences in hippocampal functional connectivity. In addition, CUD symptom counts based on the Structured Clinical Interview for DSM-5 (SCID) and the Cannabis Use Disorders Identification Test (CUDIT) significantly correlated with multiple connectivity metrics. Conclusion These data expand on emerging literature indicating that CUD is associated with dysfunction in the neural circuits underlying emotion processing. Dysfunction in emotion processing circuits may play a role in the behavioral impairments seen in emotion processing tasks in individuals with CUD, and the severity of CUD symptoms appears to be directly related to the degree of dysfunction in these circuits.
Treatment of substance use disorders among black and white adults: rates, correlates, and racial discrimination

Racial disparities in access to psychiatric treatment are well documented, but less is known about disparities in use of substance use disorder (SUD) treatment.To compare Black and White individual...
Resilience from Diversity: Population-based approach to harden models against adversarial attacks

Traditional deep learning models exhibit intriguing vulnerabilities that allow an attacker to force them to fail at their task. Notorious attacks such as the Fast Gradient Sign Method (FGSM) and the more powerful Projected Gradient Descent (PGD) generate adversarial examples by adding a magnitude of perturbation $\epsilon$ to the input's computed gradient, resulting in a deterioration of the effectiveness of the model's classification. This work introduces a model that is resilient to adversarial attacks. Our model leverages a well established principle from biological sciences: population diversity produces resilience against environmental changes. More precisely, our model consists of a population of $n$ diverse submodels, each one of them trained to individually obtain a high accuracy for the task at hand, while forced to maintain meaningful differences in their weight tensors. Each time our model receives a classification query, it selects a submodel from its population at random to answer the query. To introduce and maintain diversity in population of submodels, we introduce the concept of counter linking weights. A Counter-Linked Model (CLM) consists of submodels of the same architecture where a periodic random similarity examination is conducted during the simultaneous training to guarantee diversity while maintaining accuracy. In our testing, CLM robustness got enhanced by around 20% when tested on the MNIST dataset and at least 15% when tested on the CIFAR-10 dataset. When implemented with adversarially trained submodels, this methodology achieves state-of-the-art robustness. On the MNIST dataset with $\epsilon=0.3$, it achieved 94.34% against FGSM and 91% against PGD. On the CIFAR-10 dataset with $\epsilon=8/255$, it achieved 62.97% against FGSM and 59.16% against PGD.
Combined effect of matrix cracking and stress-free edge on delamination

The effect of the stress-free edge on the growth of local delaminations initiating from a matrix crack in (0 sub 2/90 sub 4) sub s and (+ or - 45.90 sub 4) sub s glass epoxy laminates is investigated using 3-D finite element analysis. The presence of high interlaminar normal stresses at the intersection (corner) of the matrix crack with the stress-free edge, suggests that a mode I delamination may initiate at the corners. The strain energy release rates (G) were calculated by modeling a uniform through-width delamination and two inclined delaminations at 10.6 deg and 45 deg to the matrix crack. All components of G have high values near the free edges. The mode I component of G is high at small delamination length and becomes zero for a delamination length of one-ply thickness. The total G values near the free edge agreed well with previously derived closed form solution. The quasi-3D solutions agreed well with the 3-D interior solutions.
Polymorphic DNA haplotypes at the phenylalanine hydroxylase (PAH) locus in European families with phenylketonuria (PKU)

DNA haplotype data from the phenylalanine hydroxylase (PAH) locus are available from a number of European populations as a result of RFLP testing for genetic counseling in families with phenylketonuria (PKU). We have analyzed data from Hungary and Czechoslovakia together with published data from five additional countries--Denmark, Switzerland, Scotland, Germany, and France--representing a broad geographic and ethnographic range. The data include 686 complete chromosomal haplotypes for eight RFLP sites assayed in 202 unrelated Caucasian families with PKU. Forty-six distinct RFLP haplotypes have been observed to date, 10 unique to PKU-bearing chromosomes, 12 unique to non-PKU chromosomes, and the remainder found in association with both types. Despite the large number of haplotypes observed (still much less than the theoretical maximum of 384), five haplotypes alone account for more than 76% of normal European chromosomes and four haplotypes alone account for more than 80% of PKU-bearing chromosomes. We evaluated the distribution of haplotypes and alleles within these populations and calculated pairwise disequilibrium values between RFLP sites and between these sites and a hypothetical PKU "locus." These are statistically significant differences between European populations in the frequencies of non-PKU chromosomal haplotypes (P = .025) and PKU chromosomal haplotypes (P much less than .001). Haplotype frequencies of the PKU and non-PKU chromosomes also differ significantly (P much less than .001. Disequilibrium values are consistent with the PAH physical map and support the molecular evidence for multiple, independent PKU mutations in Caucasians. However, the data do not support a single geographic origin for these mutations.(ABSTRACT TRUNCATED AT 250 WORDS)
Banking Reform in the Chinese Mirror

This paper analyzes the transactions that led to the partial privatization of China’s three largest banks in 2005/06. It suggests that these transactions were structured to allow for inter-organizational learning under conditions of uncertainty. For the foreign investors involved their participation in large financial intermediaries of central importance to the Chinese economy gave them an opportunity to learn about financial governance in China. For the Chinese banks partnering with more than one foreign investor allowed them to benefit from the input by different players in the global financial market place and to learn from the range of technical and governance expertise they offered. This model of bank reform contrasts with the privatization strategies pursued in Latin America and Central and Eastern Europe throughout the 1990s. These different experiences stand for alternative strategies of bank reform: One that relies on top down changes of the rules of the game; and another that focuses on inter-organizational learning by monitoring. It suggests that the latter model may be superior under conditions of uncertainty. The paper discusses the costs and benefits of these alternative models in the context of the global financial crisis.
Main beam jammer cancellation and target angle estimation with a polarization-agile monopulse antenna

An alternative, more cost-effective approach to cancellation and angle estimation in airborne radars is proposed. A set of preformed, phase-steered, product-pattern monopulse beams are used to form adapted sum ( Sigma ) and difference ( Delta ) beams that yield undistorted target monopulse ratio estimates while nulling both main-beam and sidelobe ECM (electronic countermeasures). The authors consider three approaches to optimal weight calculation. The first is a straightforward sample-matrix-inversion algorithm, which maximizes the signal-to-noise ratio in a prespecified look direction or, equivalently, minimizes the adapted beam residue subject to a unity-gain constraint in the prespecified look direction. The other two approaches to adaptive weight optimization are based on finding the eigenvector with the minimum eigenvalue for modified versions of R (the sample covariance matrix). Results of algorithm performance analysis are presented. The bandwidth effects of phase-steered antennas on the main beam canceller are also discussed. >
A Test of Erikson’s Theory of Ego-Stage Development by Means of a Self-Report Instrument

The validity and reliability of the Self-Description Questionnaire was tested using undergraduate and graduate students. The history and development of the instrument are reported. The validity was...
Novelty-facilitated extinction: providing a novel outcome in place of an expected threat diminishes recovery of defensive responses.

Abstract Background Experimental extinction serves as a model for psychiatric treatments based on associative learning. However, the effects of extinction are often transient, as evidenced by postextinction return of defensive behaviors. From a therapeutic perspective, an inherent problem with extinction may be that mere omission of threat is not sufficient to reduce future threat uncertainty. The current study tested an augmented form of extinction that replaced, rather than merely omitted, expected threat outcomes with novel nonthreat outcomes, with the goal of reducing postextinction return of defensive behaviors. Methods Thirty-two healthy male Sprague-Dawley rats and 47 human adults underwent threat conditioning to a conditioned stimulus paired with an electrical shock. Subjects then underwent a standard extinction protocol with shock omitted or an augmented extinction protocol wherein the shock was replaced by a surprising tone. Tests of postextinction recovery occurred 24 hours later in the absence of the tone. Results Replacing the shock with a novel nonthreat outcome, as compared with shock omission, reduced postextinction recovery (freezing in rats and anticipatory skin conductance responses in humans) when tested 24 hours later. Self-reported intolerance of uncertainty was positively correlated with recovery following standard extinction in humans, providing new evidence that postextinction recovery is related to sensitivity to future threat uncertainty. Conclusions These findings provide cross-species evidence of a novel strategy to enhance extinction that may have broad implications for how to override associative learning that has become maladaptive and offer a simple technique that could be straightforwardly adapted and implemented in clinical situations.
Minimally knotted graphs in S3

Abstract We address the following unknotting conjecture for graphs. If G is a planar graph embedded in S 3 so that π 1 ( S 3 − G ) is free and G is locally unknotted (proper subgraphs are planar), then G is unknotted. We prove the conjecture when G is any embedding of a theta-curve, handcuff, or “double θ ”, and for infinitely many other graphs which are a “sum” of graphs which satisfy the conjecture. We also give examples of minimally knotted graphs and develop an algorithm which reduces a trivalent graph to a link such that if the link is nonplanar, then the original graph is nonplanar embedded.
Carotenemia. Its influence on the validity of the icteric index.

In a paper with Hess1 one of us called attention to the occurrence of carotenemia. At the time it was pointed out that this might in certain cases cause confusion with icterus. Later it was observed that the carotenemia might be very intense in diabetic patients on the high vegetable diet of the time.It is obvious that carotene must exert some influence on the icteric index of the blood, a fact which has been appreciated by most of the workers in this field. Fiessinger, Walker and Thierry2 from their work felt that the effect was negligible, Boeck and Yater3 found that carotene accounted for from 10 to 55% of the icteric index, while White4 concluded that the influence was negligible except in marked cases of xanthemia accompanying diabetes.The subject has been reinvestigated on 161 patients, 75 of whom were suffering from diabetes mellitus, the carotene being determined in terms of the icteric index (lipochrome index) and in mg. per 100 cc. of serum. In 43 diabetic cases on which icteric indices were det...
Epithelioid Sarcoma With Heterotopic Bone: A Morphologic Review of 4 Cases

Epithelioid sarcoma is an uncommon malignancy that usually arises in the superficial soft tissues of the extremities. Classically, epithelioid sarcoma grows as nodules of mild to moderately atypical epithelioid cells, frequently with central necrosis. The stroma is variably fibrous and may rarely contain heterotopic bone. The presence of bone within epithelioid sarcoma raises a variety of lesions in the differential diagnosis, including reactive processes as well as benign and malignant neoplasms.This morphological variant of epithelioid sarcoma and its associated diagnostic pitfalls has received little attention in the literature. The authors report herein 4 cases of epithelioid sarcoma with heterotopic bone and highlight the morphological characteristics of the bone and how such variants can be distinguished from other bone-forming lesions of the soft tissues.
Radiation of topographic waves from Gulf Stream meanders

Abstract In a two-layer model of the Gulf Stream and underlying cold water mass, meander formation and pinch-off generates substantial pressure torque on the interface. This transfers vorticity to the lower layer and acts, over a sloping sea floor, as a source term for topographic waves. The source intensity is proportional to the Jacobian of surface pressure and interface elevation. Other possible source terms (interfacial or bottom shear stress curl or horizontal momentum flux divergence) are dwarfed by the pressure torque. Model calculations show that individual meander pinch-off events radiate topographic waves with characteristics very much as observed. The radiation field is quite unlike a plain monochromatic wave: the perceived frequency of oscillations varies in proportion to distance from the source.
Stress influences on anoikis.

It long has been suspected that psychosocial factors affect cancer development and progression. Although the connections between stress and cancer causation are not strong, epidemiologic and clinical studies have provided strong links between cancer progression and several stress-related factors including chronic stress, depression, and social isolation. Recent molecular and biological studies have identified specific signaling pathways that influence cancer growth and metastasis. In particular, stress hormones can have a significant impact on protecting cancer cells from undergoing the anoikis form of programmed cell death, thus, providing a mechanistic advantage for metastasis. This review provides an overview of the relationship between psychosocial factors and the avoidance of anoikis by cancer cells. Cancer Prev Res; 4(4); 481–5. ©2011 AACR.
Numerical modeling of rock-bit interaction in laminated formations

Wellbore deviations, encountered during oil well drilling operations in rocks exhibiting laminations or foliations, can be attributed to rock-bit interaction. Numerical modeling of the rock-bit interaction process in laminated formation has been performed using a finite element approach. A finite element program was developed with the assumption of plane strain. Anisotropic elements, dynamic, loading, progressive failure, and variable stiffness were used to represent the actual penetration process. The Hoek and Brown failure criterion was used in the failure analysis. An iteration method, using an incremental approach, has been applied for the continuous tooth penetration process where displacements, axial loads, strength and stiffness of elements are modified after each iteration. The program provides quantitative information on stress, displacement, and rock failure for each iteration. Furthermore, deviation due to laminated formation can be inferred and the effects of changing bit geometry can be assessed. The model also shows good quantitative agreement with laboratory wedge indentation tests.
On Chip Micropumping for Biofluids by Temperature Biased AC Electrothermal Effect

For biofluids, very limited voltage can be applied without causing reactions, even with AC voltages, so conventional electrokinetic pumps cannot function effectively. Here two innovative ACEK micropump designs are proposed, which are expected to solve the long-standing problem of on-chip pumping for biofluids. This work focuses on exploiting external heat flux or temperature bias to enhance micropumping by AC electrothermal effect. AC electrothermal effect is ubiquitous as long as electric current flows through fluid. Investigating the interplay between electric field and temperature field will be useful for the research area of electrokinetics as a whole. New methods to enhance on chip micorpumping have been presented in this paper. Inhomogenous electric fields can cause uneven Joule heating of the fluid, which generates thermal gradients and leads to mobile charges in fluid bulk. The two pumping schemes circumvent the voltage problem by introducing extra thermal gradient to generate mobile charges. The free charges then move under the electric field and induce microflows due to viscosity. Numerical simulation and preliminary experiments have successfully demonstrated the improvement in flow velocity. It enriches the repertoire for the design of ACEK micropump, and affords us more flexibility when dealing with micropumping tasks. The micropumping mechanisms proposed here are simple, robust, of small form factor, can be readily integrated into microsystems at low cost. The proposed fabrication and micropump integration process is highly manufacturable with various materials and can be easily incorporated into a fully integrated biochip. The added design flexibility from this project will lend the pump design well towards many lab-on-a-chip applications.© 2010 ASME
Diverse actions of retinoid receptors in cancer prevention and treatment.

Retinoids (retinol [vitamin A] and its biologically active metabolites) are essential signaling molecules that control various developmental pathways and influence the proliferation and differentiation of a variety of cell types. The physiological actions of retinoids are mediated primarily by the retinoic acid receptors α, β, and γ (RARs) and rexinoid receptors α, β, and γ. Although mutations in RARα, via the PML-RARα fusion proteins, result in acute promyelocytic leukemia, RARs have generally not been reported to be mutated or part of fusion proteins in carcinomas. However, the retinoid signaling pathway is often compromised in carcinomas. Altered retinol metabolism, including low levels of lecithin:retinol acyl trasferase and retinaldehyde dehydrogenase 2, and higher levels of CYP26A1, has been observed in various tumors. RARβ2 expression is also reduced or is absent in many types of cancer. A greater understanding of the molecular mechanisms by which retinoids induce cell differentiation, and in particular stem cell differentiation, is required in order to solve the issue of retinoid resistance in tumors, and thereby to utilize RA and synthetic retinoids more effectively in combination therapies for human cancer.
Bilateral circumferential macular folds in inflicted childhood neurotrauma.

PURPOSE: To report an infant with inflicted neurotrauma who exhibited bilateral circumferential macular folds. METHODS: Bedside ophthalmic examination and fundus photography using RetCam-II (Clarity Medical Systems, Pleasanton, CA). RESULTS: Both pupils were miotic and nonreactive. External and anterior segments showed no abnormality. The fundus showed bilateral diffuse multilaminar retinal, subhyaloid, and vitreous hemorrhages. Distinctive macular folds were noted bilaterally. CONCLUSION: Circumferential macular folds are most commonly found in abused infants, although it has been suggested that they may be associated with Terson syndrome and severe crush injury.
Stressors and Life Goals of Caregivers of Individuals With Disabilities

Caregivers of individuals with disabilities can experience stress as they manage caregiving responsibilities while they attempt to balance family, work, and the satisfaction of their personal goals. In this pilot study, 31 caregivers of individuals with a variety of disabilities completed a quantitative–qualitative survey. A statistically significant relationship was found between the age and severity of disability of the family member receiving care, the length of time care had been provided, the educational level and the relationship of the caregiver to the family member and reported feelings of optimism, humbleness, quality of family relationships, financial concerns, loss of control, and hope. When life goals were probed, the most common reported were achieving financial stability, having a strong, healthy family, and experiencing happiness. The implications for supporting caregivers and their families are discussed.
A Software Scheme for Multithreading on CGRAs

Recent industry trends show a drastic rise in the use of hand-held embedded devices, from everyday applications to medical (e.g., monitoring devices) and critical defense applications (e.g., sensor nodes). The two key requirements in the design of such devices are their processing capabilities and battery life. There is therefore an urgency to build high-performance and power-efficient embedded devices, inspiring researchers to develop novel system designs for the same. The use of a coprocessor (application-specific hardware) to offload power-hungry computations is gaining favor among system designers to suit their power budgets. We propose the use of CGRAs (Coarse-Grained Reconfigurable Arrays) as a power-efficient coprocessor. Though CGRAs have been widely used for streaming applications, the extensive compiler support required limits its applicability and use as a general purpose coprocessor. In addition, a CGRA structure can efficiently execute only one statically scheduled kernel at a time, which is a serious limitation when used as an accelerator to a multithreaded or multitasking processor. In this work, we envision a multithreaded CGRA where multiple schedules (or kernels) can be executed simultaneously on the CGRA (as a coprocessor). We propose a comprehensive software scheme that transforms the traditionally single-threaded CGRA into a multithreaded coprocessor to be used as a power-efficient accelerator for multithreaded embedded processors. Our software scheme includes (1) a compiler framework that integrates with existing CGRA mapping techniques to prepare kernels for execution on the multithreaded CGRA and (2) a runtime mechanism that dynamically schedules multiple kernels (offloaded from the processor) to execute simultaneously on the CGRA coprocessor. Our multithreaded CGRA coprocessor implementation thus makes it possible to achieve improved power-efficient computing in modern multithreaded embedded systems.
Vascular disease: Endovascular treatment of vertebral artery stenosis.

The safest and most effective treatment for symptomatic vertebral artery stenosis has not yet been proven. Here, we discuss the merits and pitfalls of endovascular treatment for this under-recognized disease entity.
Synthesis and ligand substituion chemistry of dinuclear, phosphido-bridged complexes of manganese. X-ray crystal structures of Mn2(μ-H)(μ-Cy2P)(CO)7(PCy2H)(1) and Mn2(μ-H)(μ-Cy2P)(CO)6(PMe32

Abstract Reaction of Mn2 (CO)10 with two equivalents of dicyclohexylphosphine in toluene at 110° produces Mn2 (μ-H)(μ-Cy2P)(CO)7(PCy2H) (1) in 60% yield. Interaction of 1 with excess trimethylphosphine produces Mn2(μ-H)(μ-Cy2P)(CO)6 (PMe3)(2 (2) in 90% yield. The X-ray crystal structures of 1 and 2 have been determined. Both structures contain two Mn atoms bridged by a Cy2P group and a hydridge. In each case, the metal atoms exhibit distorted octahedral geometry, with the phosphines occupying positions trans to the P atom of the bridging dicyclohexylphosphine. A metal-metal distance of ca. 2.9 A separates the manganese atoms in both complexes.
U‐Shaped dose‐response curves: Their occurrence and implications for risk assessment

A class of curvilinear dose-response relationships in toxicological and epidemiological studies may be roughly described by "U-shaped" curves. Such curves reflect an apparent reversal or inversion in the effect of an otherwise toxic agent at a low or intermediate region of the dose continuum. Several examples of U-shaped dose-response functions are presented to illustrate the variety of agents and end points that can follow this form. Such findings are not thought to represent a unitary phenomenon, but may be explained through numerous possible principles or mechanisms, some of which are illustrated and discussed in general terms. U-shaped dose-response curves raise important issues for toxicological and environmental health risk assessments, particularly in the identification of no-observed-effect levels and in the evaluation of multiple outcomes and the tradeoffs between potential risks and benefits of a given agent. It is especially important to avoid focusing exclusively on an apparent improvement in one end point and failing to consider other, possibly deleterious effects of the same agent.
Response rates to mail surveys published in medical journals.

Objective. The purpose of this study was to characterize response rates for mail surveys published in medical journals; to determine how the response rate among subjects who are typical targets of mail surveys varies; and to evaluate the contribution of several techniques used by investigators to enhance response rates. Methods. One hundred seventy-eight manuscripts published in 1991, representing 321 distinct mail surveys, were abstracted to determine response rates and survey techniques. In a follow-up mail survey, 113 authors of these manuscripts provided supplementary information. Results. The mean response rate among mail surveys published in medical journals is approximately 60%. However, response rates vary according to subject studied and tech- niques used. Published surveys of physicians have a mean response rate of only 54%, and those of non-physicians have a mean response rate of 68%. In addition, multivariable models suggest that written reminders provided with a copy of the instrument and telephone reminders are each associated with response rates about 13% higher than surveys that do not use these techniques. Other techniques, such as anonymity and financial incentives, are not associated with higher response rates. Conclusions. Although several mail survey techniques are associated with higher response rates, response rates to published mail surveys tend to be moderate. However, a survey's response rate is at best an indirect indication of the extent of non-respondent bias. Investigators, journal editors, and readers should devote more attention to assessments of bias, and less to specific response rate thresholds. j CLIN EPIDEMIOL 50;10:1129-1136, 1997. 0 1997 Elsevier Science Inc.
Elevated preoperative hemoglobin A1c level is predictive of adverse events after coronary artery bypass surgery

Objective Diabetes mellitus has been associated with an increased risk of adverse outcomes after coronary artery bypass grafting. Hemoglobin A1c is a reliable measure of long-term glucose control. It is unknown whether adequacy of diabetic control, measured by hemoglobin A1c, is a predictor of adverse outcomes after coronary artery bypass grafting. Methods Of 3555 consecutive patients who underwent primary, elective coronary artery bypass grafting at a single academic center from April 1, 2002, to June 30, 2006, 3089 (86.9%) had preoperative hemoglobin A1c levels obtained and entered prospectively into a computerized database. All patients were treated with a perioperative intravenous insulin protocol. A multivariable logistic regression model was used to determine whether hemoglobin A1c, as a continuous variable, was associated with in-hospital mortality, renal failure, cerebrovascular accident, myocardial infarction, and deep sternal wound infection after coronary artery bypass grafting. Receiver operating characteristic curve analysis identified the hemoglobin A1c value that maximally discriminated outcome dichotomies. Results In-hospital mortality for all patients was 1.0% (31/3089). An elevated hemoglobin A1c level predicted in-hospital mortality after coronary artery bypass grafting (odds ratio 1.40 per unit increase, P = .019). Receiver operating characteristic curve analysis revealed that hemoglobin A1c greater than 8.6% was associated with a 4-fold increase in mortality. For each unit increase in hemoglobin A1c, there was a significantly increased risk of myocardial infarction and deep sternal wound infection. By using receiver operating characteristic value thresholds, renal failure (threshold 6.7, odds ratio 2.1), cerebrovascular accident (threshold 7.6, odds ratio 2.24), and deep sternal wound infection (threshold 7.8, odds ratio 5.29) occurred more commonly in patients with elevated hemoglobin A1c. Conclusion Elevated hemoglobin A1c level was strongly associated with adverse events after coronary artery bypass grafting. Preoperative hemoglobin A1c testing may allow for more accurate risk stratification in patients undergoing coronary artery bypass grafting.
Spectroscopy Beyond the Single-Particle Limit

Scientists can now routinely detect and study single molecules and nanoparticles ( 1 ). However, direct observation of chemical processes and/or atomic motions in real time remains a challenge, primarily because ultrafast (subpicosecond) time resolution is needed. Optical techniques have recently been developed to study the dynamics of individual molecules or nanoparticles where two laser beams (a pump and a probe) are focused onto a single nano-object under a microscope ( 2 , 3 ). The spatial resolution of these measurements is limited by the diffraction of light, so that the movements of the individual atoms can only be inferred. On page 56 of this issue, Clark et al. ( 4 ) present a study of the lattice motions of individual gold nanoparticles recorded using ultrafast coherent x-ray pulses as a probe. These measurements yield three-dimensional images of the atomic displacements in the particles as a function of time, with a spatial resolution that is orders of magnitude better than what can be achieved with optical microscopes.
Effect of ammoniation on toxicity of Acremonium coenophialum infested tall fescue

Abstract Two trials were conducted to determine if toxic compounds in tall fescue ( Festuca arundinacea Schreb.) hay, infested with the endophytic fungus Acremonium coenophialum (Morgan-Jones & Gams) might be detoxified with anhydrous ammonia. The experimental arrangement in each trial was a 2 × 2 factorial of the dietary treatments with three or four replications in a randomized complete block. Dietary treatments were: (1) endophyte infested (E+) tall fescue hay; (2) endophyte free (E−) tall fescue hay; (3) ammonia-treated E+ hay; (4) ammonia-treated E− hay. Simultaneous exposure of E+ and E− hays to NH 3 (3% of dry matter) was done under a plastic sheet for 21 days. Maximum temperature of hays during ammoniation was 42.7 °C. When hays were fed at equal intakes in the digestion trial, digestibilities of organic matter and fiber were higher ( P P −1 soyabean meal. Dry matter intakes and weight gains were lower ( P P
Feedlot biomass co-firing: a renewable energy alternative for coal-fired utilities.

The swiftly growing feedlot industry in the United States upshots in the production of manure from one or more animal species in excess of what can safely be applied to farmland, in accordance with nutrient management plans. Disposal of the vast quantity of manure produced as a by-product of the cattle feeding industry is one of the major operating tasks of the industry. Aside from the traditional means of disposal as fertilizer, an alternative and attractive way of overcoming this threat is to develop processes that make use of manure as an energy resource. In the present study, the feasibility of using manure as a fuel in existing coal fired power plants is considered and appropriately termed Feedlot Biomass (FB). The technology of co-firing coal: feedlot biomass facilitates an environment friendly utilization of animal waste for the production of valuable power/steam concurrently addressing the renewable energy, groundwater contamination, and greenhouse gas concerns. Co-firing tests were performed at t...
Rate equation description of distributed feedback laser dynamics

A simple optical rate equation for a distributed feedback laser is derived following an analytical procedure that is based on transforming a known integral equation into an equivalent differential equation. Using this equation to model fluctuations in the phase and photon number, when supplemented with a rate equation for the carrier number expressions for the relaxation oscillation characteristics and linewidth are derived. We find that in a simple distributed feedback structure the relation for the relaxation oscillation frequency is identical to that of the Fabry-Perot laser. An effective linewidth-broadening factor is predicted showing strong dependence on longitudinal hole- burning. Power re-broadening of the linewidth and a nearly vanishing power-independent component are predicted. Finally, rate equations for injection-locking are derived, and a symmetric dynamically stable locking band predicted.
Germ-line immortality.

Major advances in stem cell research have occurred over the last decades. Progress has included the generation of lines of human and mouse embryonic stem (ES) cells and the identification and purification of stem cells for multiple independent lineages. Recent studies by Brinster and colleagues in this issue of PNAS (1) also suggest that the reproductive potential of an organism can be prolonged indefinitely by using germ-line stem cells. It even appears that eggs and sperm can develop from cultured mouse ES cells (2–4). Although gametes derived in vitro have yet to prove their developmental potential, these studies suggest that ES cells and germ-line stem cells share many characteristics. In most mammalian females, meiosis initiates during in utero development, such that no oogenic stem cells exist in the postnatal ovary, thereby limiting the reproductive lifespan of a woman. However, the reproductive lifespan of a man is in theory without limits. Although this reproductive potential of males has long been known, the further characterization and identification of spermatogonial stem cells is only a recent advance. Three major requirements were needed to advance spermatogonial stem cell research, including ( i ) an in vivo assay for stem cell function, ( ii ) knowledge of stem cell markers, and ( iii ) a method to maintain the stem cells continuously in culture. Similar to his pivotal studies to optimize egg culture and transgenesis (reviewed in refs. 5 and 6), Brinster's group has systematically made giant leaps toward these goals. A decade ago, Brinster and Zimmerman (7) and Brinster and Avarbock (8) published in PNAS methods for spermatogonial transplantation. These studies were a major breakthrough in the development of an assay for in vivo stem cell function. Male mice lacking spermatogenesis were chosen as recipients. Wild-type mice or transgenic mice carrying a round spermatid-expressed β-galactosidase ( lacZ ) gene (or, …
Novel physically loaded and interlocked electrode developed for ionic polymer-metal composites (IPMCs)

Described is a novel fabrication process of manufacturing ionic polymeric metal composites (IPMC's) biomimetic sensors, actuators and artificial muscles equipped with physically loaded and interlocked (PLI) electrodes. The underlying principle of processing this novel PLI-IPMC's is to first physically load a conductive primary powder into the ionic polymer network forming a dispersed particulate layer. This primary layer functions as a major conductive medium. Subsequently, this primary layer of dispersed particles of a conductive material is interlocked within the polymer network with smaller secondary particles via chemical plating, which used reducing agents to load another phase of conductive particles within the first layer. In turn, both primary and secondary particles can be secured within the ionic polymer network and reduce the potential intrinsic contact resistances between large primary particles. Furthermore, electroplating can be applied to integrate the entire primary and secondary conductive phases and serve as another effective interlocking electrode. In this paper we describe the details of this newly developed technique to efficiently produce a PLI-IPMC loaded with spherical silver particles (D10<0.8 micrometers , D50<1.5 micrometers , D90<2.5 micrometers ; Asur<6 m2/g) and subsequently interlocked by palladium (Dp~50nm, via a chemical reducing process). It has been observed that such a PLI-IPMC is quite comparable in performance with the traditional Platinum loaded and Gold electro-plated IPMC's but enjoys a much smaller manufacturing cost. Yet it produces a low surface resistivity (less than 1 (Omega) /square) which is highly desirable in creating more uniform deformation.