cssi/SciSciGPT-SciSciNet huggingface dataset:
A Probabilistic Compute Fabric Based on Coupled Ring Oscillators for Solving Combinatorial Optimization Problems

Nondeterministic polynomial time hard (NP-hard) combinatorial optimization problems (COPs) are intractable to solve using a traditional computer as the time to find a solution increases very rapidly with the number of variables. An efficient alternative computing method uses coupled spin networks to solve COP. This work presents a first-of-its-kind coupled ring oscillator (ROSC)-based scalable probabilistic Ising computer to solve NP-hard COPs. An integrated coupled oscillator network was designed with 560 ROSCs that mimic a coupled spin network. Each ROSC can be coupled to any of its neighbors using programmable back-to-back (B2B) inverter-based coupling mechanism. The ROSC-based spins and B2B inverter-based coupling were optimized to work under a wide range of system noise as well as voltage and temperature variations. Randomly generated 1000 max-cut problems were mapped and solved in the hardware. The integrated Ising computer produced satisfactory solutions of max-cut problems when compared with commercial software running on a CPU. Experiments show that the integrated CMOS-based Ising computer can find the solution to NP-hard problems with an accuracy of 82%–100%. In addition, the repeated measurements of the same problem showed that the Ising computer can traverse through several local minima to find high-quality solutions under various voltage and temperature variation conditions. The experimental results show that ROSCs are a potential candidate for a dedicated hardware accelerator aiming to solve a wide range of COPs.
Is Tactical Allocation a Winning Strategy

In this study, we evaluated the absolute and risk-adjusted performance of tactical allocation mutual funds and benchmarked them to various benchmark indexes from January 1994 to October 2016. We found that tactical allocation mutual funds underperformed all benchmark indexes and had lower absolute and risk-adjusted performance during the period. Tactical allocation funds, however, had lower risk or standard deviation of returns compared to all asset categories with the exception of bonds. We also computed seven-factor alpha and found that tactical allocation funds had significantly negative alpha during the entire period, including during the 2008 financial crisis. Our findings indicate that tactical allocation funds did not outperform the benchmarks, and investors would have been better off with passively managed funds that followed benchmark indexes. TOPICS:Mutual funds/passive investing/indexing, performance measurement, risk management, financial crises and financial market history Key Findings ▪ Tactical allocation mutual funds underperformed all benchmark indexes and had lower absolute and risk-adjusted performance from January 1994 to October 2016. Investors would have been better off with passively managed funds that followed benchmark indexes. ▪ For most investors, sticking to a long-term strategic allocation is the best course of action. ▪ Although we found that tactical allocation funds do not deliver superior performance on a risk-adjusted basis, our results should be interpreted with caution. We did not examine variation in asset class sensitivity among funds, and whether this might be related to alpha generation.
What is the rate of COVID-19 infection in a population seeking dental care?

Background Although rates of COVID-19 have remained low among US dentists, we wanted to determine the risk of COVID-19 in patients presenting for oral health care Methods A retrospective chart review of all emergency department consults was performed from June 2020 to December 2020 Pearson correlation coefficients were used to compare rates to city-wide prevalence (p < 0 05) Results We located 203 encounters with 149 tests, and 10 cases of COVID-19 Cases were strongly correlated with city-wide positivity-rate (R=0 9147, p=0 0039) All positive cases were asymptomatic and afebrile, and half (50%) visited a dentist within a week of consultation Conclusions The rate of COVID-19 in a population seeking oral health care reflects the community positivity-rate Asymptomatic or presymptomatic patients present risks to providers, staff, and other patients Practical Implications Dentists should remain vigilant during the ongoing COVID-19, even with vaccination rollout The CDC maintains an accessible website with easy access to your state’s positivity rate and case load
A Radiologic Grading System for Assessing the Radiographic Outcome of Treatment in Lymphatic and Lymphatic-Venous Malformations of the Head and Neck.

BACKGROUND AND PURPOSE: Two-thirds of lymphatic malformations in children are found in the head and neck. Although conventionally managed through surgical resection, percutaneous sclerotherapy has gained popularity. No reproducible grading system has been designed to compare sclerotherapy outcomes on the basis of radiologic findings. We propose an MR imaging-based grading scale to assess the response to sclerotherapy and present an evaluation of its interrater reliability. MATERIALS AND METHODS: A grading system was developed to stratify treatment outcomes on the basis of interval changes observed on MR imaging. By means of this system, 56 consecutive cases from our institution with formally diagnosed head and neck lymphatic malformations treated by sclerotherapy were retrospectively graded. Each patient underwent pre- and posttreatment MR imaging. Each study was evaluated by 3 experienced neuroradiologists. Interrater reliability was assessed using the Krippendorff α statistic, intraclass coefficient, and 2-way Spearman ρ correlation. RESULTS: The overall Krippendorff α statistic was 0.93 (95% CI, 0.89-0.95), denoting excellent agreement among raters. Intraclass coefficients with respect to consistency and absolute agreements were both 0.97 (95% CI, 0.96-0.98), illustrating low variability. Every combination of individual rater pairs demonstrated statistically significant (P < .01) linear Spearman ρ correlations, with values ranging from 0.90 to 0.95. CONCLUSIONS: The proposed radiographic grading scale demonstrates excellent interrater reliability. Adoption of this new scale can standardize reported outcomes following sclerotherapy for head and neck lymphatic malformation and may aid in the investigation of future questions regarding optimal management of these lesions.
Deinococcus radiodurans PriA is a Pseudohelicase.

Reactivation of repaired DNA replication forks in bacteria is catalyzed by PriA helicase. This broadly-conserved bacterial enzyme can remodel the structure of DNA at a repaired DNA replication fork by unwinding small portions of duplex DNA to prepare the fork for replisome reloading. While PriA’s helicase activity is not strictly required for cell viability in E. coli, the sequence motifs that confer helicase activity upon PriA are well-conserved among sequenced bacterial priA genes, suggesting that PriA’s duplex DNA unwinding activity confers a selective advantage upon cells. However, these helicase sequence motifs are not well-conserved among priA genes from the Deinococcus-Thermus phylum. Here, we show that PriA from a highly radiation-resistant member of that phylum, Deinococcus radiodurans, lacks the ability to hydrolyze ATP and unwind duplex DNA, thus qualifying D. radiodurans PriA as a pseudohelicase. Despite the lack of helicase activity, D. radiodurans PriA has retained the DNA binding activity expected of a typical PriA helicase, and we present evidence for a physical interaction between D. radiodurans PriA and its cognate replicative helicase, DnaB. This suggests that PriA has retained a role in replisome reloading onto repaired DNA replication forks in D. radiodurans despite its lack of helicase activity.
Magnetic Shielding for a Spaceborne Adiabatic Demagnetization Refrigerator (ADR)

The Goddard Space Flight Center has studied magnetic shielding for an adiabatic demagnetization refrigerator. Four types of shielding were studied: active coils, passive ferromagnetic shells, passive superconducting coils, and passive superconducting shells. The passive superconducting shells failed by allowing flux penetration. The other three methods were successful, singly or together.
Professional Standards and Principles for Evaluations

Members of most professions and many other public service fields are expected to comply with given standards or codes of performance and service. The standards and codes have several important functions: • protect consumers and society from harmful practices • provide a basis for accountability by the service providers • provide an authoritative basis for assessing professional services • provide a basis for adjudicating claims of malpractice • help assure that service providers will employ their field’s currently best available practices • identify needs for improved technologies • provide a conceptual framework and working definitions to guide research and development in the service area • provide general principles for addressing a variety of practical issues in the service area • present service providers and their constituents with a common language to facilitate communication and collaboration • provide core content for training and educating service providers • earn and maintain the public’s confidence in the field of practice
CRITIQUE - OF “FACTORS INFLUENCING NITRATE ACQUISITION BY PLANTS: ASSIMILATION AND FATE OF REDUCED NITROGEN”

The nitrate assimilation pathway of root tissue can be considered as a branched system with both transport and metabolic components. Nitrate entering the root tissue may be reduced, accumulated in storage deposits, or transferred centripetally inward for deposition in the xylem. Amino acids synthesized from the entering nitrate, or the nitrate itself, may thereby serve as the nitrogen source for the above ground parts of the plant but there is little definitive information indicating how the relative proportions of the two sources are regulated. The nitrate uptake system is apparently substrate inducible and subject to restriction by accumulated nitrate, or products of its reduction. It is also closely attuned to the composition of the ambient medium and to the transport of material from the shoots. Nitrate reduction and deposition of nitrate in the xylem are both closely dependent upon nitrate uptake, neither activity is sustained well by previously accumulated nitrate. There is in general a decided lack of specific information related to how the overall nitrate assimilation pathway in root tissue is regulated and how alterations in the activities of a given process affect the activities of the other components of the pathway.
Albatrosses, eagles and newts, Oh My!: exceptions to the prevailing paradigm concerning genetic diversity and population viability?

Numerous recent papers have demonstrated a central role for genetic factors in the extinction process or have documented the importance of gene flow in reversing population declines. This prompted one recent publication to declare that a revolution in conservation genetics has occurred. Contemporaneously with this revolution are a series of papers demonstrating long-term population persistence for several species despite having little or no detectable genetic variation. In a couple of notable cases, populations have been shown to have survived for centuries at small population size and with depleted levels of genetic variation. These contradictory results demand an explanation. In this review, I will show that these results do not necessarily fly in the face of theory as sometimes stated. The reconciliation of these two sets of observations relies on the incorporation of two major concepts. (1) Genetic factors do not act in a vacuum and it is their interaction with the environment, the strength and type of selection imposed, and the life history of the organism that determine the relative importance of genetic factors to extinction risk. (2) The relationship between molecular estimates of genetic variation and evolutionary potential, the relevance of genetic bottlenecks to adaptive genetic variation, and the nature of the stochastic process of extinction must be better integrated into expectations of population viability. Reports of populations persisting for hundreds of generations with very little detectable genetic variation provide us not only with valuable information but also with hope. However, recent studies suggest that we should not be sanguine about the importance of genetic diversity in the conservation of biodiversity.
Segmented Capital Markets and the Cost of External Finance

Segmented capital markets may allow firms to reduce their cost of capital by increasing their reliance on the relatively cheaper market. However, this potential benefit is attenuated by the firm's costs of accessing the markets. This paper models a firm with access to two segmented capital markets, and illustrates how higher costs of accessing either market lead to lower firm values. While access costs clearly impact the firm's ability to arbitrage the two markets, we focus on a more subtle effect. Access to multiple markets may reduce the value loss arising from uncertainty in internally generated funds. The model also suggests a methodology for measuring access costs to segmented markets, allowing us to test our model on a sample of large banking firms. We label banks with relatively lower costs of accessing the two markets as more "financially flexible." Our two key findings are 1) banks with greater financial flexibility have greater value, and 2) banks with greater financial flexibility devote a smaller percentage of assets to cash and marketable securities, consistent with the notion that financial flexibility reduces the sensitivity of firm profits to internal wealth shocks, thus reducing the firm's need to carry financial slack.
The trustworthy computing security development lifecycle

This paper discusses the trustworthy computing security development lifecycle (or simply the SDL), a process that Microsoft has adopted for the development of software that needs to withstand malicious attack. The process encompasses the addition of a series of security-focused activities and deliverables to each of the phases of Microsoft's software development process. These activities and deliverables include the development of threat models during software design, the use of static analysis code-scanning tools during implementation, and the conduct of code reviews and security testing during a focused "security push". Before software subject to the SDL can be released, it must undergo a final security review by a team independent from its development group. When compared to software that has not been subject to the SDL, software that has undergone the SDL has experienced a significantly reduced rate of external discovery of security vulnerabilities. This paper describes the SDL and discusses experience with its implementation across a range of Microsoft software.
Adult Respiratory Distress Syndrome in Full-Term Newborns

Since 1984, 11 newborns with severe respiratory distress have been treated whose clinical characteristics appear distinctive. Characteristics of these neonates were as follows: (1) they were full term by obstetric and neonatal criteria, (2) they had diffuse bilateral alveolar opacification on chest radiographs during the acute illness, (3) each had an acute perinatal triggering insult, (4) the neonates required continuous positive pressure ventilation for at least 48 hours with FiO2 greater than 0.50 for at least 12 hours, (5) they needed positive end-expiratory pressure of 6 cm of H2O or greater within three days of the triggering event, (6) there were no other known causes of these clinical conditions. Ten (91%) neonates had evidence of other organ dysfunction in addition to the lungs. Trials of hyperventilation in nine and tolazoline in five failed to improve oxygenation. Ten infants who underwent trials of increased positive end-expiratory pressure greater than or equal to 6 cm of H2O without other concurrent changes in ventilator settings responded with prompt increases in PaO2 (median increase 84 mm Hg, range 22 to 196 mm Hg). All 11 babies survived but required prolonged mechanical ventilation and supplemental oxygen. We suggest that adult respiratory distress syndrome can and does occur in newborns. A trial of positive end-expiratory pressure greater than or equal to 6 cm of H2O should be considered in full-term infants with severe respiratory distress in whom other causes can be excluded.
What Is Unique About Nanomedicine? The Significance of the Mesoscale

Unlike drugs and medical devices, for which long standing and continuously improving quality assurance/quality control infrastructures exist, many nano-based products lack well-defined standards that are useful to manufacturers and regulators. Inherent variabilities in nanoparticle sizes and shapes, their large surface-to-volume ratios, and their mesoscale interactions with subcellular structures, suggest new complexities and challenges that must be met before widespread application of nanomedicines can be expected.
The performance of a repeatable control scheme for redundant robots

This paper addresses the determination of joint motions for a given end effector displacement in kinematically redundant manipulators. It is well known that velocity control schemes, such as pseudoinverse control, do not guarantee repeatability. But it is possible to obtain repeatable solutions by controlling the manipulator joints so that they behave like elastic couplings. The joint configuration adopted by the manipulator at a given point in task space is one which minimizes the potential energy of the system and is unique. In this paper, we investigate the existence and uniqueness of solutions (joint displacements) for a given end effector displacement. We identify singularities in the algorithm and their physical significance. Finally, we show that it is important to consider the stability of the manipulator at a given configuration and discuss practical considerations in implementing such algorithms.
Neurocognitive effects of proton radiation therapy in adults with low-grade glioma

To understand neurocognitive effects of proton radiation therapy (PRT) in patients with low-grade glioma, we evaluated 20 patients who received this therapy prospectively and over 5 years with a comprehensive neuropsychological battery. 20 patients were evaluated at baseline and at yearly intervals for up to 5 years with a battery of neuropsychological measures that assessed intellectual, attention, executive, visuospatial and memory functions as well as mood and functional status. We evaluated change in cognitive functioning over time. We analyzed the relationship between cognitive performance and tumor location and also examined whether patients' performance differed from that reported in a study of normative practice effects. Overall, patients exhibited stability in cognitive functioning. Tumor location played a role in performance; those with tumors in the left hemisphere versus in the right hemisphere were more impaired at baseline on verbal measures (p < .05). However, we found greater improvement in verbal memory over time in patients with left than with right hemisphere tumors (p < .05). Results of our study, the first to investigate, in depth, neurocognitive effects of PRT in adults with low-grade gliomas, are promising. We hypothesize that the conformal advantage of PRT may contribute to preservation of cognitive functioning, although larger sample sizes and a longer period of study are required. Our study also highlights the need to consider normative practice effects when studying neurocognitive functioning in response to treatment over time, and the need to utilize comprehensive neuropsychological batteries given our findings that differentiate patients with left and right hemisphere tumors.
Sparsity and normalization in word similarity systems

We investigate the problem of improving performance in distributional word similarity systems trained on sparse data, focusing on a family of similarity functions we call Dice-family functions (Dice 1945Ecology26(3): 297–302), including the similarity function introduced in Lin (1998Proceedings of the 15th International Conference on Machine Learning, 296–304), and Curran (2004 PhD thesis, University of Edinburgh. College of Science and Engineering. School of Informatics), as well as a generalized version of Dice Coefficient used in data mining applications (Strehl 2000, 55). We propose a generalization of the Dice-family functions which uses a weight parameter α to make the similarity functions asymmetric. We show that this generalized family of functions (α systems) all belong to the class of asymmetric models first proposed in Tversky (1977Psychological Review84: 327–352), and in a multi-task evaluation of ten word similarity systems, we show that α systems have the best performance across word ranks. In particular, we show that α-parameterization substantially improves the correlations of all Dice-family functions with human judgements on three words sets, including the Miller–Charles/Rubenstein Goodenough word set (Miller and Charles 1991Language and Cognitive Processes6(1): 1–28; Rubenstein and Goodenough 1965Communications of the ACM8: 627–633).
A constraint satisfaction cryptanalysis of bloom filters in private record linkage

For over fifty years, "record linkage" procedures have been refined to integrate data in the face of typographical and semantic errors. These procedures are traditionally performed over personal identifiers (e.g., names), but in modern decentralized environments, privacy concerns have led to regulations that require the obfuscation of such attributes. Various techniques have been proposed to resolve the tension, including secure multi-party computation protocols, however, such protocols are computationally intensive and do not scale for real world linkage scenarios. More recently, procedures based on Bloom filter encoding (BFE) have gained traction in various applications, such as healthcare, where they yield highly accurate record linkage results in a reasonable amount of time. Though promising, no formal security analysis has been designed or applied to this emerging model, which is of concern considering the sensitivity of the corresponding data. In this paper, we introduce a novel attack, based on constraint satisfaction, to provide a rigorous analysis for BFE and guidelines regarding how to mitigate risk against the attack. In addition, we conduct an empirical analysis with data derived from public voter records to illustrate the feasibility of the attack. Our investigations show that the parameters of the BFE protocol can be configured to make it relatively resilient to the proposed attack without significant reduction in record linkage performance.
Uptake of PCBs contained in marine sediments by the green macroalga Ulva rigida.

Abstract The uptake of PCBs contained in marine sediments by the green macroalga Ulva rigida was investigated in both laboratory and field experiments. Under laboratory conditions, total PCBs (tPCBs) uptake was significantly greater in live vs dead plants. The concentration of tPCB taken up in live plants was greatest in the first 24 h (1580 μg kg −1 dry weight), and then increased at a lower rate from day 2 to 14. Dead plants had a significantly lower tPCB concentration after 24 h (609 μg kg −1 dry weight) and lower uptake rate through day 14. Lesser chlorinated PCB congeners (below 123) made up the majority of PCBs taken up. Congener composition in both laboratory and field experiments was correlated to congener log K ow value and sediment content. Field experiments showed that Ulva plants could concentrate PCBs to 3.9 mg kg −1 in 24 h. Thus, U. rigida is capable of removing PCBs in sediments at a rapid rate.
Travel Along the Mobius Strip: Somerset Maugham and Gu Hongming East of Suez

During his 1919–20 trip to China, English writer Somerset Maugham paid a special visit to Gu Hongming, an Edinburgh-educated Chinese philosopher and so-called ‘Confucian Sage’. By exploring the enigmatic interactions between Maugham and Gu in the context of colonial travel, this article illustrates the important role of psychological projection in the exchanges among elite travellers during an age of empire. Beyond a simple Orientalist or Occidentalist approach, the author proposes a new framework modelled on the geometric puzzle of the ‘Mobius strip’, a twisted and closed one-sided surface, to highlight the intersubjective nature of the East–West continuum. At first glance, East and West, as in the writings of Maugham and Gu, are on opposite sides of the strip, appearing static and well defined to each other at any given moment. However, the paradox of a Mobius strip lies in its twirling and continuous motion: East and West are constantly interacting, defining one another through contacts like Gu's and M...
In vivo X-ray fluorescence of lead in bone

The in vivo measurement of lead in bone by K X-ray fluorescence (K XRF) is becoming an increasingly widely utilized technique for assessing long-term lead dosimetry. Several groups have already reported the development of in vivo measurement systems, the majority adopting the 109 Cd/backscatter K XRF technique because of its substantial advantages in terms of a robust measurement, lower detection limit (compared with 57 Co/90°), absence of the need for sedation of younger subjects, and lower effective (radiation) dose when calculated according to the most recent guidelines. The advantages of the 109 Cd system are primarily a consequence of the physics principles of the technique. The apparatus of each XRF technique is transportable, facilitating easy establishment of mobile laboratory facilities. More research is needed to substantiate claims made for particular XRF technologies, but both L and K XRF techniques provide the possibility of improved understanding of the body's handling of the ubiquitous toxin lead.
Ultrasonic vibration-assisted pelleting for cellulosic biofuel manufacturing: Investigation on power consumption

Abstract Cellulosic ethanol produced from cellulosic biomass is an alternative to petroleum-based transportation fuels. Raw cellulosic biomass has low density, causing high costs in their storage, transportation, and handling. Ultrasonic vibration-assisted (UV-A) pelleting can increase the density of cellulosic biomass. Effects of UV-A pelleting variables on pellet quality (density, durability, stability, and strength) and sugar yield have been reported. However, power consumption in UV-A pelleting has not been fully investigated. This paper presents an experimental investigation on power consumption in UV-A pelleting of wheat straw. Effects of input variables (biomass moisture content, biomass particle size, pelleting pressure, and ultrasonic power) on power consumption are investigated. Results show that power consumption in UV-A pelleting increases as moisture content and particle size decrease, and as pelleting pressure and ultrasonic power increase.
Self-Handicapping and Obesity: Is There a Sympathetic Audience Out There?

After reading a case description of a 20-year-old woman, subjects attributed her personal shortcomings to her weight rather than to herself per se. In particular, people who scored higher on a measure of self-handicapping were even more likely to attribute shortcomings to a person's weight and excuse or overlook them. A person who attributes shortcomings to being overweight will very likely find a sympathetic audience. These results support the suggestion by Baumeister, Kahn, and Tice (1990) that obesity can be a self-handicapping strategy.
Ischemic reperfusion causes lipid peroxidation and fiber degeneration

Although the neuropathology of ischemic fiber degeneration (IFD) is relatively well known, its pathogenesis is poorly understood. One putative mechanism of IFD is oxidative stress, causing a breakdown of the blood-nerve barrier (BNB) and lipid peroxidation. We evaluated the effect of ischemic reperfusion of rat sciatic-tibial nerve seeking biochemical and pathologic evidence of BNB disruption and lipid peroxidation. Ischemia, caused by the ligation of the supplying arteries to sciatic-tibial nerve, was maintained for 3 h, followed by reperfusion. Reperfusion resulted in an increase in nerve lipid hydroperoxides, greatest at 3 h, followed by a gradual decline over the next month. Nerve edema and IFD consistently became more severe with reperfusion, indicating that oxidative stress impairs the BNB (edema) and causes IFD. Reduced reperfusion was greatest over distal sciatic nerve and midtibial nerve at day 7. The most ischemic segment (midtibial), of nonreperfused ischemic nerves (duration 3 h), underwent both edema and IFD that was as pronounced as those of other segments after reperfusion, and underwent a smaller increase with reperfusion, suggesting that ischemia alone can also cause IFD and edema. The type of fiber degeneration was that of axonal degeneration.
The effectiveness of animal repellents on dogs and cats in the laboratory and field

Abstract A laboratory and field study of two animal repellents was conducted to determine the effectiveness of each on cats and dogs foraging from plastic garbage bags. In laboratory studies, 12 mixed-breed dogs, 18 beagle dogs and 8 cats were given a choice between commerical pet food in repellent-treated and non-treated plastic bags. Laboratory results showed that one repellent containing methyl nonyl ketone and cinnamic aldehyde reduced damage to bags 82.8% by mixed-breed dogs, 69.2% by beagle dogs, and 100% by mixed-breed cats. In the 3-month field study of 120 sites in urban ( n = 21), suburban ( n = 86) and rural ( n = 13) environments, the plastic bags contained fried chicken, paper and tin cans. At any given site, all bags were untreated (control) or sprayed with a repellent. Fifty-two percent of the damage to garbage bags was done by dogs alone, 6% by cats alone, 21% by dogs and cats, and 22% by raccoons either alone or at sites also damaged by cats and dogs. Only 17.8% of the control garbage remained undamaged for 1 week, 56% was damaged the first day they were placed on the site. Methyl nonyl ketone reduced damage to garbage bags by 31.4% and cinnamic aldehyde plus methyl nonyl ketone reduced damage by 40.1% in field studies. It was concluded that the laboratory study did not adequately simulate field conditions, and that neither repellent would be of practical value in preventing scavenging by animals. These results are in agreement with other studies looking at the efficacy of olfactory repellents with dogs. It is concluded that adequate restraint of dogs and cats is the only highly effective method of preventing garbage scavenging by these animals.
Effect of isoproterenol and acetylcholine treatment in vitro on cyclic nucleotides in mouse sex accessory organs

Abstract The effect of treatment in vitro with either isoproterenol or acetylcholine on the levels of cyclic AMP and cyclic GMP in male mouse prostate gland and seminal vesicle was studied. In each experiment, tissues were preincubated with aminophylline (5 mM) for 10 min prior to exposure to the autonomic agonist. Treatment with 1 × 10−5 M isoproterenol for 5 min resulted in significant increases in endogenous levels of cyclic AMP in both prostate glands and seminal vesicles obtained from intact mature male mice. This effect of isoproterenol on cyclic AMP could be blocked by pretreatment for 10 min with an equimolar (1 × 10−5 M) concentration of propranolol. On the other hand, isoproterenol (1 × 10−5 M for 5 min) had no effect on sex accessory organ levels of cyclic GMP. If sex accessory organs obtained from intact mature male mice were subjected to acetylcholine (1 × 10−5 M for 5 min), significant increases (P
The cellular effects of a unique pesticide sulfluramid (N-ethylperfluorooctane sulphonamide) on rabbit renal proximal tubules.

Abstract The cellular effects of sulfluramid (N-ethylperfluorooctane sulphonamide, NEPFOS) and its major metabolite perfluorooctane sulphonamide (PFOS) were examined using a suspension of rabbit renal proximal tubules as a model. NEPFOS and PFOS were potent stimulators of proximal tubule basal oxygen consumption (QO2), with initial effects exhibited at 5–10 μ m and maximal effects at 50–200 μ m . The increase in basal QO2 was ouabain insensitive, which suggests that NEPFOS and PFOS may act by uncoupling oxidative phosphorylation. Exposure of tubule suspensions to NEPFOS or PFOS concentrations of 100 μ m or higher for 60 min produced tubule death, indicated by an increase in the release of lactate dehydrogenase. The tubule death did not appear to result from alkylation or lipid peroxidation, since glutathione and malondialdehyde levels were unaffected. To determine the mechanism by which NEPFOS and PFOS increased tubule QO2, the effects of NEPFOS and PFOS on isolated renal cortical mitochondria were examined. NEPFOS (10 μ m ) and PFOS (5 μ m ) increased state-4 respiration of mitochondria in the absence of a phosphate acceptor. These results suggest that NEPFOS and PFOS uncouple oxidative phosphorylation and may produce cytotoxicity through this mechanism.
Design and simulation of two-dimensional superlattice steep transistors

We report design of double-gate metal-oxide-semiconductor field-effect-transistors having InGaAs/InAlAs superlattices between the N+ source and a planar InGaAs channel. As with nanowire superlattice transistors, the 2-D superlattice bandgap reduces injection into the channel of electrons having energy above the source Fermi energy. Simulated ballistic transport characteristics of FETs using a three-well superlattice show 29-37.5-mV/decade minimum subthreshold swing and 390-A/m ON-current given 0.1-A/m OFF-current and a 0.2 V power supply.
Nitrogen ion implantation of silicon-containing diamond-like carbon (Si-DLC) coatings synthesized by ion beam assisted deposition

Abstract Hard, adherent, and low-friction silicon containing diamond-like carbon coatings (Si-DLC) have been synthesized by 40 keV Ar + ion beam assisted deposition (IBAD) of tetraphenyl-tetramethyl-trisiloxane oil, on 8.90 cm (3.5 in) diameter aluminum alloy substrates. The Si-DLC coatings were implanted with nitrogen ions to doses of 3×10 15 , 3×10 16 , and 3×10 17 ions/cm 2 . The Si-DLC coating synthesis and the subsequent nitrogen ion implantation at 80 keV took place in a non-mass analyzed ion implanter. The thickness of the implanted coatings, measured with the aid of a profilometer, remained equal to the thickness of the unimplanted coating, and photon tunneling microscopy showed some surface roughening from the implantation process. The unlubricated steel ball-on-disk friction coefficient increased with increasing implant dose. However, the wear rate of the coating, determined with the aid of an optical microscope and a stylus profilometer, decreased with increasing implant dose.
Cavo Atriopulmonary Anastomosis Via a Nonprosthetic Medial Tunnel

A surgical technique is described to perform a total bypass of the venous ventricle (TBPVV) via a cavo atriopulmonary anastomosis wherein a medial atrial tunnel is constructed using autologous tissue. The procedure offers the advantage of maintaining low atrial pressure at the sinus node area without the use of prosthetic material. It also represents a good method for conversion of a bidirectional Glenn to a TBPVV avoiding surgical damage of the sinus node area.
Simultaneous hepatic and renal involvement in acute syphilis - Case report and review of the literature

An unusual case of simultaneously occurring acute syphilitic hepatic and renal disease is presented and a concise literature review of both the pathological and clinical findings in this disease is included. Hepatic and renal biopsies were useful in excluding other diagnostic possibilities and in establishing the correct diagnosis in the case presented.
p53 and NF-κB: different strategies for responding to stress lead to a functional antagonism

The p53 transcription factor responds to a variety of intrinsic stresses, such as DNA damage, hypoxia, and even oncogene activation. NF-κB responds to a large number of extrinsic stresses such as cytokine activation and infectious diseases. The p53 tumor suppressor limits the consequences of stress by initiating cell death, senescence, or cell cycle arrest and promotes metabolic patterns in the cell to favor oxidative phosphorylation. NF-κB, the oncogene, promotes cell division, which initiates the innate and adaptive immune responses utilizing large amounts of glucose in aerobic glycolysis, resulting in the synthesis of substrates for cell division. Thus these two transcription factors, both of which have evolved to respond to different types of stress, have adopted opposite strategies and cannot function in the same cell at the same time. On activation of one of these transcription factors, the other is inactivated. This is achieved at several places in the p53 and NF-κB pathways where regulatory proteins act on both p53 and NF-κB with opposite functional consequences. These internodal sites create core regulatory circuits essential for integrating two central pathways in cells.
A meta-analysis of dopamine use in hypotensive preterm infants: blood pressure and cerebral hemodynamics

A meta-analysis of dopamine use in hypotensive preterm infants: blood pressure and cerebral hemodynamics
Evolutionary and Ecological Implications of Primate Seed Dispersal

In this paper, we evaluate patterns of fruit eating and seed dispersal in monkeys and apes and draw an important distinction between 1) the ecological consequences of primates as seed dispersers and 2) the evolutionary implications of primates on the seed and fruit traits of the plant species they exploit. In many forest communities, primates act as both seed predators and seed dispersers and are likely to have an important ecological impact on patterns of forest regeneration and tree species diversity. Evidence from Kibale National Park, Uganda, and Manu National Park, Peru, as well as several other South American sites indicates that monkeys and apes display a wide range of fruit-processing behaviors, including spitting seeds, dropping seeds, masticating seeds, and swallowing seeds. Differences in consumer body size, diet, ranging patterns, and oral and digestive morphology result in different patterns in the distance and distribution of seeds from the parent plant. In the case of South American monkeys, for example, despite their relatively small body size, platyrrhines were found to exploit larger fruits and swallow larger seeds on average than did Old World monkeys and apes of the Kibale forest. We found little evidence to support the existence of a coevolutionary relationship between a single or set of primate dispersers and the particular plant species they disperse. This is due to variability in the manner in which monkeys and apes select fruits and treat seeds, the fact that many species of primates and nonprimates exploit and disperse the same fruit species, and the fact that extremely high levels of postdispersal seed, seedling, and sapling mortality serve to dilute the influence that any primate species may have on the recruitment of the next generation of adult trees. It is apparent that many primate lineages exhibit dental, digestive, and/or sensory adaptations that aid in the exploitation of particular food types and that many lineages of flowering plants have evolved characteristics of fruits and seeds that facilitate seed dispersal. However, in light of currently available data, we argue that these represent evolutionary rather than more strictly defined coevolutionary relationships.
Enacting solidarity : Unions and migrant youth in Thailand

The A. examines the activities of some young migrant workers, participants in Thailand's labor movement, and their strategies for solidarity in the face of economic insecurity. Activities sponsored by some independent Bangkok unions and labor solidarity groups draw upon both modern urban commercial forms as well as traditional ritual practices to promote class-based unity within a predominantly youthful and migrant labor force. Though limited in both means and opportunity for effective oppositional expression, unionized migrants explore new ways of thinking about themselves and their experiences through creative enactments of solidarity. In the process, migrant youth rework dominant symbols and practices in ways that contest hegemonic authority. Their grassroots actions reveal a dynamic struggle to produce and engage an alternative discourse of class-based identity by members of a workforce widely deemed to have little potential for collective action.
Repositioning accuracy of a noninvasive head fixation system for stereotactic radiotherapy

We report on the repositioning accuracy of patient setup achieved with a noninvasive head fixation device for stereotactic radiotherapy. A custom head mask which attaches to our stereotactic radiosurgery head ring assembly is fabricated for each patient. The position and orientation of a patient in the stereotactic space at the time of treatment are determined from analyzing portal films containing images of radio‐opaque spheres embedded in a custom mouthpiece. From analysis of 104 setups of 12 patients, we find that the average distance between the treated isocenter and its mean position is 1.8 mm, and that the standard deviations of the position of the treated isocenter in stereotactic coordinate space about its mean position are less than 1.4 mm in translation in any direction and less than 1° of rotation about any axis.
Low-velocity impact response of laminated beams subjected to initialstresses

Finite element procedures are used in conjunction with a numerical algorithm to compute the impact response of a graphite-epoxy laminated beam subjected to tensile initial stresses. The effect of initial stresses on the contact duration, impact force, coefficient of restitution, and bending and shear stresses are discussed. The analytically computed contact force history and strain response are compared with some experimental results.
Oxidative Modification of Glucose-6-phosphate Dehydrogenase from Leuconostoc mesenteroides by an Iron(II)-Citrate Complex

Abstract Incubation of glucose-6-phosphate dehydrogenase fromLeuconostoc mesenteroides with Fe2+ and citrate results in rapid O2-dependent inactivation of the enzyme. Maximal rate of inactivation occurred at equimolar concentrations of Fe2+ and citrate. Loss of enzyme activity appears to be the result of selective oxidative modification, as evidenced by a corresponding increase in protein carbonyl content. Partially inactivated enzyme remained predominantly in the dimeric form with no change in the apparent affinity of the remaining active subunits for substrate. Modified Glu-6-PDH was, however, more susceptible to heat denaturation. Our results suggest that the Fe2+-citrate complex binds to the glucose 6-phosphate binding site and then undergoes reaction with H2O2 formed in solution leading to the oxidative modification of amino acids essential for enzyme activity.
Imaging performance of annular apertures. 6: Limitations by optical surface deviations

The performance of optical systems is limited by imperfect optical surfaces that degrade the images below the level set by wave theoretical limits. The central irradiance functions are derived for slit and circular apertures with five distributions of wavefront errors and for a range of maximal wavefront deviations. For practical frequency of occurrence distributions of wavefront deviations, the point spread and the image energy integral functions are determined. Practical performances of optical systems are derived and performance limits discussed.
Effects of the aged microenvironment on CD4+ T cell maturation.

Abstract Contributing to the functional alterations of the aged immune system is the accumulation of memory CD4 + T lymphocytes and decline in the proportion of naive cells occurring with advancing age. During attempts to alter the naive to memory ratio of CD4 + cells in aged mice, it was observed that regeneration of the peripheral T cell compartment resulted in a population which possessed the same memory cell-enriched characteristics as the unmanipulated age-matched controls. Thymopoiesis in aged mice does not appear to be altered in such a way as to give rise to emigrants with `memory-like' characteristics. The aged peripheral microenvironment does, however, cause the accelerated maturation of mature, naive CD4 + T cells to the memory state.
The structure and synthesis of xanthomicrol

Abstract Xanthomicrol is shown to be 5,4′-dihydroxy-6,7,8-trimethoxyflavone by a combination of physical and degradative methods. Its synthesis from pentamethoxybenzene is described.
National Trends in Endovascular and Open Renal Artery Interventions for Renal Artery Stenosis and the Impact of Recent Randomized Controlled Trials

Conclusions: The protective effects of estrogen on AAAs can be divided into central and peripheral estrogen effects depending on the site of estrogen synthesis. Central estrogen synthesis from the ovaries accounted for the majority of the protective effects of estrogen, while peripheral estrogen conversion accounted for only one-third of the effect. These findings may explain the increased incidence of AAAs in postmenopausal women lacking central estrogen synthesis.
Scar tissue: dementia's tangled web.

Text and Context consists of excerpts from literature (novels, short stories, poetry, plays or creative non-fiction) followed by an accompanying essay discussing the significance of the work for clinical practice or medical education.The novel Scar Tissue by Michael Ignatieff follows a family through the tensions and upheavals that accompany a diagnosis, decline, and death from dementia. This excerpt from an early chapter describes a family meeting with a neurologist to discuss Mother’s test results. The narrator is a philosophy professor. His brother is a neuropathologist, their father a soil chemist, and their mother a painter.
End-of-life care: an educational intervention for rural nurses in southeastern USA.

Aim: To assess the impact of three educational presentations as an intervention for increasing knowledge of end-of-life care for rural nurses in assisted living and nursing home environments. Design: A repeated measures design (quantitative component) evaluated the effects of the educational intervention. Two open ended questions yielded qualitative data. Sample and Setting: A convenience sample (n = 9) of Registered Nurses and Licensed Practical Nurses employed in an assisted living facility or nursing home in the rural, southeastern region of the USA. Level of nursing experience ranged from 6 to 28 years. Analysis: Frequency distributions, difference of means test for paired samples. Results: Post test scores were significantly higher (t = 6.999; p < 0.001) than pretest scores regarding overall knowledge on end-of-life care. Attitudes and perceptions of participants changed in defining what constitutes a ‘good death’. Conclusions: Classroom educational presentations are an effective means of changing at...
Application of cognitive therapy for trauma-related guilt (CT-TRG) with a Vietnam veteran troubled by multiple sources of guilt

Kubany and Manke (1995) presented a model of guilt that emphasizes its cognitive elements and described a structured cognitive therapy format aimed at alleviating trauma-related guilt (CT-TRG). This article illustrates the practice of CT-TRG with a Vietnam combat veteran suffering from several “classic” Vietnam War-related sources of guilt. Seven sources of guilt were addressed over 7 hours in a 1-day “marathon” therapy session. After therapy, the veteran reported dramatic reductions in guilt, PTSD, and depression symptomatology and a marked increase in self-esteem. These improvements were sustained at 8- and 22-month follow-ups. It is suggested that intensive treatment of multiple guilt issues may be necessary to alleviate overall guilt among many combat veterans and survivors of other kinds of traumatic events as well. Numerous descriptions of therapist-client interactions illustrate some of the nuances of CT-TRG and may facilitate its implementation by interested clinicians.