cssi/SciSciGPT-SciSciNet huggingface dataset:
Kinetic model for thin film stress including the effect of grain growth

Residual stress during thin film deposition is affected by the evolution of the microstructure. This can occur because subsurface grain growth directly induces stress in the film and because changing the grain size at the surface affects the stress in new layers as they are deposited. We describe a new model for stress evolution that includes both of these effects. It is used to explain stress in films that grow with extensive grain growth (referred to as zone II) so that the grain size changes throughout the thickness of the layer as the film grows. Equations are derived for different cases of high or low atomic mobility where different assumptions are used to describe the diffusion of atoms that are incorporated into the grain boundary. The model is applied to measurements of stress and grain growth in evaporated Ni films. A single set of model parameters is able to explain stress evolution in films grown at multiple temperatures and growth rates. The model explains why the slope of the curvature measur...
Social Cyber-Security

Social Cyber-Security is an emerging scientific discipline. Its methodological and scientific foundation, key challenges, and scientific direction are described. The multi-disciplinary nature of this field and its emphasis on dynamic information strategies is considered.
A Attitudes Regarding Hypertension Among Older African-American Adults

Before hypertension can be effectively treated in older African-American patients, the clinician must become familiar with the attitudes of this population regarding this disease. One of the major barriers to effective antihypertensive therapy is having a clinician who is not aware of potential impact that patient attitudes have on compliance with office visits and pharmacological therapy. One group of investigators did a survey of African Americans, Hispanic Americans, and non-Hispanic white adults over the age of 75 years that assessed ethnic differences in perceptions regarding the cause, prevention, and treatment of hypertension as well as associations between perceptions and the use of preventive health services (1). The survey found that African Americans felt that hypertension resulted from poor health behaviors and stress, but that it was both preventable and treatable. In contrast, non-Hispanic whites felt that hypertension is a result of various mechanistic causes and heredity; also, they felt hypertension was treatable but not preventable. Finally, Hispanic Americans were more likely to state that hypertension was the result of aging and poor health behaviors and was not susceptible to treatment.
Chaotic Vibration-Based Damage Detection in Fluid-Structural Systems

A panel forced by unsteady aerodynamic loads is investigated in the supersonic flow regime. This aeroelastic system exhibits complex dynamics including limit cycle oscillations, and chaos. A finite-difference method and proper orthogonal decomposition are employed to detect parametric changes. The sensitivity of the chaotic dynamics to parametric changes is shown to be an effective tool for detecting structural modifications, such as variations of the stiffness of the upstream and downstream mounting points. Most current studies of such problems are based on linear theories. In contrast, the results presented herein are obtained using chaotic dynamics, and have the advantage of an increased accuracy in detecting damage and monitoring structural health.
Shortage of influenza vaccine in 2000-2001: did it change patient beliefs?

Abstract Objectives To determine which patient beliefs associated with influenza vaccination changed during a vaccine shortage year (2000–2001) from a nonshortage year (1999–2000). Methods Elderly patients ( n =319), who had been previously interviewed about the 1999–2000 influenza season, were interviewed regarding the 2000–2001 season. Participants were from inner-city and suburban medical practices receiving influenza vaccine supply on time or late in the season. Results Although vaccination rates did not diminish due to the influenza vaccine shortage (73% in 1999–2000 vs 74% in 2000–2001), some patient attitudes changed. More respondents expressed concerns about the influenza vaccine (3% in 1999–2000 vs 12% in 2000–2001, p p =0.005); that if one person in the household “got the flu” others would also (71% 1999–2000 vs 67% 2000–2001, p p =0.02). Conclusions The influenza vaccine shortage resulted in a small increase in concerns about influenza vaccine, even in a population with good access to vaccine and high vaccination rates. Vaccine availability updates should include reassurances of vaccine safety and efficacy.
Evolution of Thermoregulatory Function in Cetacean Reproductive Systems

Modern cetaceans possess a suite of morphological adaptations that permit their existence in the marine environment (e.g., Howell, 1930; Slijper, 1936, 1979). Their streamlined body shape, hypertrophied axial musculoskeletal system, thick blubber layer, and de novo dorsal fin and flukes are morphological features that reduce the energetic costs of both swimming (e.g., Fish and Hui, 1991; Williams et al., 1992; Fish, 1993a,b; Pabst, 1996) and whole body thermoregulation (e.g., Worthy and Edwards, 1990; Koopman et al., 1996).
A novel total body digital photography smartphone application designed to detect and monitor skin lesions: a pilot study

Although some smartphone applications are designed for total body photography (TBP), few offer the specificity that enables self- as well as dermatologist-, detection of new lesions, or change in lesion color or in size as little as 1mm, on an ongoing basis. The aim of this study is to assess the sensitivity of a novel TBP application in the detection of changes to color and size of simulated skin lesions. Twenty-five subjects underwent one study visit. After baseline photography, new artificial markings were made or naturally occurring pigmented lesions located in any anatomical region were enhanced/enlarged, and a second matching set of photographs was then taken. From all 25 subjects, a total of 262 skin markings were evaluable. Of these, 241 (92%) were detected by the app, which resulted in an overall sensitivity of 92%. The high sensitivity establishes the app as capable of providing reliable self-TBP that allows detection and monitoring of new skin lesions or change in both size and color. This method greatly enhances the ability to accomplish ongoing self-monitoring and yet provides quality informing images to the dermatologist to assist in decision-making with the patient.
Passing and the Costs and Benefits of Appropriating Blackness

The socioeconomic position of Blacks in America cannot be fully contextualized without considering the marginalization of their racialized social identities as minorities who have historically comb...
Non-fatal self-inflicted versus undetermined intent injuries: patient characteristics and incidence of subsequent self-inflicted injuries

Background Non-fatal self-inflicted (SI) injuries may be underidentified in administrative medical data sources. Objective Compare patients with SI versus undetermined intent (UI) injuries according to patient characteristics, incidence of subsequent SI injury and risk factors for subsequent SI injury. Methods Truven Health MarketScan was used to identify patients’ (aged 10–64) first SI or UI injury in 2015 (index injury). Patient characteristics and subsequent SI within 1 year were assessed. A logistic regression model examined factors associated with subsequent SI. Results Among analysed patients (n=44 806; 36% SI, 64% UI), a higher proportion of patients with SI index injury were female, had preceding comorbidities (eg, depression), Medicaid (vs commercial insurance), treatment in an ambulance or hospital and cut/pierce or poisoning injuries compared with patients with UI index injury. Just 1% of patients with UI had subsequent SI≤1 year vs 16% of patients with SI. Among patients with UI index injury, incidence of and risk factors for subsequent SI injury were similar across assessed age groups (10–24 years, 25–44 years, 45–64 years). Severe injuries (eg, treated in emergency department), cut/pierce or poisoning injuries, mental health and substance use disorder comorbidities and Medicaid (among adult patients) were risk factors for subsequent SI among patients with UI index injuries. Conclusions Regardless of circumstances that influence clinicians’ SI vs UI coding decisions, information on incidence of and risk factors for subsequent SI can help to inform clinical treatment decisions when SI injury is suspected as well as provide evidence to support the development and implementation of self-harm prevention activities.
An acoustical analysis of the merger of /ɲ/ and /nj/ in Buenos Aires Spanish

Buenos Aires Spanish (BAS) is well known for the sound change that led the palatal obstruent to become a post-alveolar fricative. However, that obstruent is not the only palatal phoneme undergoing sound change in BAS. The present study investigates the production of /ɲ/ and /nj/ in BAS, which have been reported as merging (Malmberg 1950). Previous research suggests that some speakers produce a ‘traditional’ (alveolo)palatal nasal, while other speakers realize /ɲ/ with two distinct non-simultaneous constrictions: alveolar/postalveolar and palatal (Kochetov & Colantoni 2011). An acoustic analysis is based on the speech of 33 speakers (15 males, 17 females; from four age groups: 15–19 years old, 20–29 years, 30–45 years and 45+ years) and was obtained by measuring duration and formant contours in the tautosyllabic vocalic portion. Results reveal that /ɲ/ and /nj/ are not fully merged, as some speakers produce differences. Specifically, the results indicate that production differences between men and women disappear as age decreases, with female speakers being more innovative. Findings provide evidence that the sound change is still progressing and probably nearing completion, and show that the palatal system in BAS is losing the (alveolo)palatal nasal.
Design for Manufacturing: Tolerancing and Optimization

We present recent work that produces optical designs that have increased robustness to misalignments. In other words, we optimize a design for maximum as-built performance, not for maximum nominal performance. We also discuss future extensions.
Introduction to “#MeToo Movement”

The #MeToo movement was started in 2006 by Tarana Burke to recognize experiences of sexual assault and harassment, particularly by women of color in low-income communities. The movement encourages ...
PIM-Assembler: A Processing-in-Memory Platform for Genome Assembly

In this paper, for the first time, we propose a high-throughput and energy-efficient Processing-in-DRAM-accelerated genome assembler called PIM-Assembler based on an optimized and hardware-friendly genome assembly algorithm. PIM-Assembler can assemble large-scale DNA sequence dataset from all-pair overlaps. We first develop PIM-Assembler platform that harnesses DRAM as computational memory and transforms it to a fundamental processing unit for genome assembly. PIM-Assembler can perform efficient X(N)OR-based operations inside DRAM incurring low cost on top of commodity DRAM designs (∼5% of chip area). PIM-Assembler is then optimized through a correlated data partitioning and mapping methodology that allows local storage and processing of DNA short reads to fully exploit the genome assembly algorithm-level’s parallelism. The simulation results show that PIM-Assembler achieves on average 8.4× and 2.3 wise× higher throughput for performing bulk bit-XNOR-based comparison operations compared with CPU and recent processing-in-DRAM platforms, respectively. As for comparison/addition-extensive genome assembly application, it reduces the execution time and power by ∼5× and ∼ 7.5× compared to GPU.
Reproductive outcomes of women aged 40 and older undergoing IVF with donor sperm.

Study question Do women ≥40 years old without a male partner who utilize donor sperm have the same reproductive outcomes as those who utilize their partner's sperm? Summary answer After controlling for relevant confounders, women ≥40 years old using donor sperm for IVF have significantly higher odds of having a live birth compared to those utilizing their partner's sperm. What is known already Women who are unpartnered or in same-sex relationships are by definition not infertile, but may choose to conceive using donor sperm. It is not known how IVF outcomes are affected with the use of donor sperm compared to women utilizing their partner's sperm, particularly at very advanced maternal ages. Study design, size, duration This is a retrospective cohort study conducted at a university-affiliated center of women undergoing IVF with fresh embryo transfer between 2008 and 2018. Participants/materials, setting, methods Patients were divided into two groups based on the ejaculated sperm source utilized: donor or partner sperm. Live birth rate was the primary outcome. Pregnancy rate was the secondary outcome. Multivariable logistic regression was performed and adjusted for age, the developmental stage of the embryo, and the number of embryos transferred. Unadjusted odds ratio (OR) and adjusted OR (aOR) with 95% CI for pregnancy and live birth were estimated. Statistical significance was denoted by P Main results and the role of chance A total of 3910 cycles in women ≥40 years old were analyzed, of which 307 utilized donor sperm and 3603 utilized their partner's sperm to conceive. In the univariate analysis, patients utilizing donor sperm were found to have similar pregnancy rates as those utilizing partner sperm (41.0 vs 39.8%, OR: 0.95, 95% CI: 0.75-1.20). After adjusting for age, the number of embryos transferred and the developmental stage of the embryos, the model estimates did not vary (aOR: 1.22, 95% CI: 0.95-1.56). Similarly, the univariate analysis for live birth did not demonstrate a difference between groups (19.2 vs 17.8%, OR: 0.91, 95% CI: 0.67-1.22). However, after a similar adjustment was made for confounders, the use of donor sperm was associated with statistically significant increased odds of live birth (aOR: 1.38, 95% CI: 1.01-1.88). Limitations, reasons for caution As with any retrospective study, the potential for residual confounding exists, despite attempts to control for this with regression modeling. Wider implications of the findings Women ≥40 years old who are unpartnered or in same-sex relationships can be counseled that their odds of a live birth are slightly better than women in heterosexual relationships utilizing their partner's sperm. These findings serve to further refine and individualize counseling on the expected IVF outcomes for women in this population. Study funding/competing interest(s) No funding was sought for this study. The authors declare no competing interests. Trial registration number N/A.
Abstract MP30: Reporting of Sex-Specific Results in Randomized Clinical Trials of Acute Stroke (2010-2020)

Introduction: When reporting primary results, it is recommended that RCTs report sex-specific outcomes. We reviewed the reporting of sex-specific outcomes in contemporary acute stroke RCTs. Methods...
The Certification Role of Insider Participation in Pipe Transactions

In this paper we investigate whether certification or self-dealing is the underlying motive for insider participation in private placements. In light of the increasing popularity and liquidity provided by Private Investments in Public Equity (PIPEs), our question is particularly current and important. Certification motives manifest themselves in lower discounts and control-related terms being frequently negotiated when insiders are present. Announcement wealth effects are higher when insiders participate than when they are absent from private placements. Leading investor identity matters for the signal sent by the insiders’ participation. Specifically, when hedge funds lead private placements, the insiders’ certification role is muted. Overall, our empirical findings are in line with the certification hypothesis and suggest that contractual terms and other participating investor types play a role in explaining investors’ incentives, an issue that has been long-debated in the academic literature.
Survival in primary hyperparathyroidism over five decades (1965–2010) a population-based retrospective study

Abstract Context Survival in patients with primary hyperparathyroidism (PHPT) remains uncertain. Objective To update survival in patients with PHPT in a United States community population. Design Retrospective cohort study. Setting Community population in Rochester, Minnesota. Participants Residents who met criteria for PHPT from 1965 to 2010. Interventions Survival was estimated using the Kaplan Meier product-limit method. The Cox proportional hazards model was used to determine associations, as relative hazards (RR) with 95% confidence intervals (CI), of various risk factors with time to death. Main outcome measure The overall age and gender-adjusted survival compared to white Minnesota residents. Results We identified 1139 PHPT individuals, 76% female, with a median age of 58 years. Most were observed without parathyroidectomy (69%). The relative risk of death among the entire cohort was 0.996 (95% CI: 0.91–1.09, P = 0.935) which was not different compared to Minnesota residents. Those with maximum serum calcium level ≥ 10.8 mg/dL (0.7 mg/dL above the reference range) had an increase in mortality (RR 1.32, 95% CI: 1.10–1.58, P = 0.002). Survival among all PHPT individuals after parathyroidectomy was no different from expected (RR = 1.06, 95% CI 0.89–1.28; P = 0.508). Mortality was significantly decreased after parathyroidectomy in those with serum calcium levels ≥10.8 mg/dL (HR 0.47, 95% CI: 0.36–0.61, P Conclusions Mortality in the entire cohort was not different from expected. PHPT patients with a maximum serum calcium level ≥ 10.8 mg/dL had increased mortality. Survival was improved after parathyroidectomy in those with this degree of hypercalcemia.
Cultural political economy, crisis management, and COVID-19 in the United States

The Coronavirus Disease 2019 (COVID-19) has ravaged the world. The pace at which this pandemic spread left policy makers scrambling to understand the virus and craft ameliorative policy measures, w...
Safety of Intravenous Olanzapine Administration at a Tertiary Academic Medical Center.

BackgroundAlthough approved by the Food and Drug Administration for intramuscular administration only, analyses have described the administration of intravenous push (IVP) olanzapine, particularly ...
Biomass supply curves for western juniper in central Oregon, USA, under alternative business models and policy assumptions.

Abstract This study estimates a supply of juniper from private lands to determine how much of the available juniper ( Juniperus occidentalis Hook) can be economically supplied at alternative prices if a market was to develop for using juniper as a biomass source. While juniper is native to central Oregon, current land management practices have led to a significant increase in its density on much of the landscape. There could be potential benefits related to juniper removal for private landowners, as well as social benefits associated with water and habitat enhancement. At current densities, juniper on these private lands has negative impacts that diminish biodiversity, reduce forage grass and tie up water resources. The difference in the value of cattle productivity resulting from the presence of juniper as well as any forgone net returns from the sale of juniper to the biofuel industry reflects the opportunity cost to the rancher. This opportunity cost does not capture the complete opportunity cost associated with juniper removal since it does not incorporate the enhanced benefits of biodiversity and increased water availability, and thus reflects a lower bound. The supply curves for juniper as a source for biofuel shift in response to profitable harvesting coordination between landowners, the Oregon Biofuel Producer tax credit and increased positive externalities due to juniper removal. Because of restricted road networks the available source of juniper was limited by access — only 27% of the juniper area is on private rangelands, which is the focus of this report. This study identified supply costs under alternative business models and policy assumptions for an aggregate supply of 2.75 million tonnes and illustrated an analytic technique that could be replicated in other areas.
The M/G/s/s Queue

This article describes the M/G/s/s queueing system, also known as the Erlang loss model. Customers arrive to this stochastic service system according to a homogeneous Poisson process and request service from one of s parallel servers (s ≥ 1). The service times are assumed to be independent and identically distributed with a finite mean. Because there is no waiting space in the system, arriving customers who find all s servers busy are lost. Summarized herein are the primary operating characteristics of the M/G/s/s system, namely, the steady-state probability distribution of the number of occupied servers and the steady-state blocking probability (the Erlang B formula). Also summarized is the closely related delay probability (the Erlang C formula) for systems with unlimited waiting space. Some computational issues related to the Erlang B and C formulae are also discussed. Keywords: queueing system; erlang loss model; erlang B formula; service systems
The tattered curtain hypothesis revised: Coastal jets limit cross-shelf larval transport

Exchange and retention of coastal waters modulate dispersal of marine larvae, affecting marine ecosystem dynamics. A hypothesis was put forward in the 1980s describing the coastal upwelling front as a “tattered curtain” that retains larvae. This front was envisioned to be broken up by squirts and eddies, hitting the coast under upwelling relaxation events. Here we revise this hypothesis by using an idealized ocean model of an eastern boundary upwelling current, and an idealized particle/larvae model appropriate for shelf-spawning benthic species. Modeled larval settlement patterns were controlled by retention in the core of the upwelling jet, bounded by regions of high-velocity shear on the flanks of the jet. Squirts, filaments, poleward-moving eddies, and meanders modulated settlement patterns locally, while dense packets moved equatorward within the upwelling jet. Correlation between settlement (i.e., particles 20–40 d old <10 km from shore) and wind was low for a lagged wind product (r=0.33) and moderate for a 20-d integrated wind product (r=0.62). We determined that it is not upwelling relaxation but sustained, moderate upwelling that can result in a highly retentive jet that entrains larvae and acts as a barrier to cross-shelf transport; however, the amount of retention is highly variable. Settlement was low after strong, persistent upwelling completely tattered the jet. Jet cores in general should act as important retentive transport barriers across diverse coastal systems, a view supported by dynamical theory, modeling studies, and larval recruitment observations.
A large-scale storage and transfer system for distribution of liquid helium as a refrigerant medium.

To prevent cavitation and overspeeding of the Centaur space vehicle engine turbo-pumps, the pump internals and casings must be refrigerated to cryogenic temperatures prior to introduction of the liquid-hydrogen propellant. Originally, liquid hydrogen was bled from the vehicle fuel tank through the turbopumps until conditions were adequate for engine ignition. This procedure was to be accomplished in flight after booster separation and required 20 to 30 sec.
A Rayleigh B\'enard Convective Instability Study Using Energy Conserving Dissipative Particle Dynamics

A Rayleigh Benard instability study using the energy conserving dissipative particle dynamics method is presented here for the first time. The simulation is performed on an ideal dissipative particle dynamics fluid in a three dimensional domain with carefully selected parameters to make the convection terms in the equation more dominant than the conduction ones. Beyond a critical temperature difference a two cell pattern is observed as the dominant structure. As the temperature is increased further, the density changes in the system are sharp with formation of distinct high density layers close to the cold wall. Doubling the length of the domain led to the formation of four convection cells with the same cell diameter as before, confirming the invariance of the pattern formation in that dimension. Changes in the height of the domain led to cells with more uniform looking patterns. The results and patterns seen here are qualitatively similar to previous studies performed on rarefied gases.
Perceived Peer Delinquency and Externalizing Behavior Among Rural Youth: The Role of Descriptive Norms and Internalizing Symptoms.

Little research has examined the way in which perceptions of peer behavior (i.e., descriptive norms) influence externalizing behavior among rural adolescents. Using a social norms framework, the current study examined gender differences in the relationship between perceived delinquency among friends and externalizing behavior in a sample of rural adolescents. Based on previous research, the authors proposed that adolescents experience negative emotional responses when they believe that their peers are engaging in delinquency, which subsequently influences externalizing behavior. Consequently, internalizing symptoms were explored as a mediator of the relationship between perceived friend delinquency and externalizing behavior. Data came from the NC-ACE Rural Adaptation Project, a longitudinal panel study of adolescents in two rural, economically disadvantaged counties with exceptional racial/ethnic diversity (29 % White, 25 % African American, 25 % American Indian, 12 % Mixed Race/Other, 9 % Hispanic/Latino). Using multiple group structural equation modeling (N = 3489; 51 % female), results indicated that perceived friend delinquency was significantly related to externalizing behavior and this relationship did not vary by gender. Internalizing symptoms fully mediated the relationship between perceived friend delinquency and externalizing behavior and the path between perceived friend delinquency and internalizing symptoms was stronger for males. Implications of these relationships for prevention and intervention programming for externalizing behavior were highlighted.
Thermal runaway reaction hazards and mechanisms of hydroxylamine with acid/base contaminants

Hydroxylamine (HA) has been involved in two incidents since 1999 because of its thermal instability and incompatibility. In this study, thermal runaway reactions of hydroxylamine with various concentrations of KOH and HCl were studied using the reactive system screening tool (RSST) and automatic pressure tracking adiabatic calorimeter (APTAC). The thermokinetic data, such as onset temperature, heat of reaction, maximum self-heat rate, maximum pressure rate, and non-condensable gas pressure, were compared with those of hydroxylamine solution without added impurity. Our study shows that the thermal decomposition behavior of hydroxylamine is affected by the presence of acid/base, and mixing of hydroxylamine with acid/base may cause thermal decomposition at lower temperatures. Different decomposition pathways can be initiated by hydrogen ion and hydroxide ion. The decomposition mechanisms of hydroxylamine in alkaline and acidic solutions are proposed based on the products, information from the literature, and quantum mechanical calculations. The experimental results are discussed in terms of the proposed reaction mechanisms.
Analysis of amino acid supplementation effects on hepatocyte cultures using flux balance analysis.

Abstract When cultured hepatocytes are exposed to challenging environments such as plasma, they frequently suffer a decline in liver-specific functions. Media supplements are sought to reduce or eliminate this effect. A rational design approach for amino acid supplementation in hepatocyte culture has been developed in our prior work, and designed amino acid supplementation (DAA) was found to increase urea and albumin production. To fully characterize the metabolic state of hepatocytes under different amino acid supplementations, a number of metabolite measurements are performed in this work and used in a metabolic network flexibility analysis framework including thermodynamic constraints to determine the range of values for the intracellular fluxes. A metabolic objective prediction model is used to infer the metabolic objectives of the hepatocytes and to quantify the intracellular flux distribution for three different amino acid supplementations. The results illustrate that DAA leads to greater fluxes in ...
The Adoption of New Technologies: Understanding Hollywood's (Slow and Uneven) Conversion to Color

Hollywood converted to sound in three years. In comparison, Hollywood's conversion to color required more than three decades, and included a three-year period in which the share of color movies declined from 58 to 31percent. We investigate this puzzling adoption profile using detailed data on 7,022 movies between 1940 and 1959. These data indicate differences in studio size and complementarity between genre and color impeded the rapid diffusion of color. These data also indicate that disadoption followed weak returns to a wave of color releases that were encouraged by the introductionof a low-cost color process.
Contribution of various substrates to total citric acid cycle flux and ]anaplerosis as determined by13C isotopomer analysis and O2 consumption in the heart

A simple relationship between parameters derived from a13C NMR isotopomer analysis and O2 consumption is presented that allows measurement of the absolute rate of acetyl-CoA oxidation and anaplerotic flux in tissues oxidizing a mixture of four substrates. The method was first applied in a study of the effects of work state and β-adrenergic stimulation on net acetate oxidation and anaplerosis in the isolated working rat heart. The results demonstrate that the anticipated ratio of 2 between O2 consumption and TCA cycle flux for hearts oxidizing only acetate holds at low workload when anaplerosis is low, but deviates toward a factor of 3 under high workload conditions when anaplerosis is increased. This analysis was also extended to hearts that oxidize a more physiological mixture of substrates including long-chain fatty acids, acetoacetate, lactate, pyruvate, and glucose. We show that the contribution each substrate makes to total TCA cycle flux can be determined by combined13C NMR and O2 consumption measurements. The present study also demonstrates that stimulation of anaplerosis (by addition of propionate) can significantly alter the relative contribution each substrate makes to total TCA cycle flux. We conclude that if13C labeling patterns are selected appropriately, a comprehensive picture of flux through all major metabolic pathways feeding the cycle can be determined in a single experiment even when complex physiological mixtures of substrates are provided.
Estrogen-induced refractoriness to the pressor effects of infused angiotensin II☆☆☆

Abstract Estrogen may be important in the hemodynamic changes that develop during pregnancy; its role in the development of vascular refractoriness to the pressor effects of infused angiotensin II is unknown. We, therefore, examined the pressor responses to six doses of angiotensin II (0.115 to 5.73 μg/min) in unanesthetized, nonpregnant sheep both before and after treatment with either high-dose or low-dose 17β-estradiol (E 2 ) and constructed dose-response curves. Although mean arterial pressure was unchanged after the infusion of E 2 , cardiac output rose 28% and systemic vascular resistance fell 19% (p 2 ; however, the pressor response after E 2 was decreased 30% to 50%. Plasma renin activity rose from 1.15 ± 0.09 ng/ml · hr to 2.57 ± 0.39 and 3.21 ± 0.61 ng/ml · hr with low-dose and high-dose E 2 , respectively (p 2 -induced change.
Coloring translates and homothets of a convex body

We obtain improved upper bounds and new lower bounds on the chromatic number as a linear function of the clique number, for the intersection graphs (and their complements) of finite families of translates and homothets of a convex body in $${{\mathbb{R}}^n}$$ .
Blood supply to the femoral head and avascular necrosis

Abstract Despite advances in the treatment of fractures and dislocations of the hip, avascular necrosis (AVN) remains one of the two most frequent complications encountered. To understand the pathogenesis and treatment of this condition, this article describes the circulation to the femoral head. The reported incidence of AVN varies considerably with different studies, but overall it is much higher in displaced than in undisplaced intracapsular fractures. The clinical picture and prognosis are discussed in this article, and the measures for early diagnosis are reviewed. A quantitative system for evaluation and staging that helps in establishing a prognosis and determining treatment is described. Specific measures for management are reviewed. Although ideally the treatment goal is to preserve the femoral head, for most patients who sustain posttraumatic AVN, treatment will be symptomatic until such time as pain and disability justify arthroplasty. At the point, the majority of patients will undergo total hip replacement that yields gratifying and durable results.
An Amperometric Fructose Biosensor Based on Fructose Dehydrogenase Immobilized in a Membrane Mimetic Layer on Gold

A prototype amperometric fructose biosensor based on membrane-bound fructose dehydrogenase (Gluconobacter sp.) and the coenzyme ubiquinone-6 immobilized in a membrane mimetic layer on a gold electrode has been constructed and tested. A bare gold electrode first was modified through chemisorption of a mixture of octadecyl mercaptan and two short-chain disulfides, 3,3‘-dithiodipropionic acid and cystamine dihydrochloride. The membrane-bound enzyme, coenzyme, and additional phospholipid were codeposited through a detergent dialysis protocol. The short-chain modifiers may provide electrostatic interactions with enzyme surface charges, while the alkanethiolate and phospholipids enable hydrophobic interaction with the largely lipophilic, membrane-bound enzyme. At oxidizing potentials, the enzyme electrode responded with catalytic current densities up to 45 μA/cm2 when exposed to fructose at 10 mM. The sensor exhibited a response time of less than 20 s, a sensitivity of 15 μA/cm2·mM and a detection limit of less...
Acceleration of Particles to High Energies in Earth’s Radiation Belts

Discovered in 1958, Earth’s radiation belts persist in being mysterious and unpredictable. This highly dynamic region of near-Earth space provides an important natural laboratory for studying the physics of particle acceleration. Despite the proximity of the radiation belts to Earth, many questions remain about the mechanisms responsible for rapidly energizing particles to relativistic energies there. The importance of understanding the radiation belts continues to grow as society becomes increasingly dependent on spacecraft for navigation, weather forecasting, and more. We review the historical underpinning and observational basis for our current understanding of particle acceleration in the radiation belts.
Interaction of ovine pituitary adenylate cyclase-activating peptide (PACAP-38) with rat lung membranes.

Abstract The binding of ovine pituitary adenylate cyclase-activating peptide (PACAP-38) to rat lung membranes was investigated using [ 125 I]PACAP-38 as radioligand. Binding was rapid at 37°C, reversible, saturable, and time, concentration, and temperature dependent. Kinetic parameters derived from saturation experiments revealed a K d = 100 ± 15 p M , B max = 310 ± 36 fmol/mg protein, and a Hill slope factor ( n H ) of 1.17 ± 0.12 . Various chemically synthesized analogues of PACAP-38, as well as related peptides, were tested for their ability to displace [ 125 I]PACAP-38. Of those that had an IC 50 , the following order of potency was determined: PACAP-38 ( IC 50 = 25 n M) ≥ [Ile 2 ]PACAP-38 ( IC 50 = 31 n M) > PACAP-27 ( IC 50 = 54 n M) > [Tyr 1 ]PACAP-38 ( IC 50 = 104 n M) > GHRH (1–29) NH 2 ( IC 50 = 108 n M) > PHI ( IC 50 = 181 n M) > [Ser 2 ]PACAP (2–38) ( IC 50 = 198 n M) . Glucagon, PHM, secretin, and GIP exhibited little affinity in the same binding assay. Vasoactive intestinal peptide (VIP) had an IC 50 in excess of 1 μ M . When [ 125 I]VIP was used as radioligand, PACAP-27 had an IC 50 = 0.2 n M > PACAP-38 ( IC 50 = 0.5 n M) > VIP ( IC 50 = 16 n M) . A novel analog of PACAP-38, [4-Cl- d -Phe 6 ,Leu 17 ]PACAP-38, was able to displace [ 125 I]VIP very efficiently ( IC 50 = 1 n M) , but had little potency in displacing [ 125 I]PACAP-38 ( IC 50 = 320 n M) . The results presented suggest that PACAP-38 binds to single, noninteracting binding sites on rat lung membranes that are distinct from those for VIP, but could be shared with PACAP-27; PACAP-38 can also efficiently bind to the VIP receptor(s), but VIP has much less potency toward the PACAP-38 receptor. Moreover, modification of the PACAP-38 molecule, either through chain length or amino acid residue substitutions, results in apparent decreased binding.
Regulation of Interleukin-8 Gene Expression by Interleukin-1β, Osteotropic Hormones, and Protein Kinase Inhibitors in Normal Human Bone Marrow Stromal Cells

Interleukin-8 (IL-8), a potent neutrophil chemotactic peptide that elicits pleiotropic biological effects is secreted in large amounts by normal human osteoblastic and bone marrow osteoprogenitor stromal (HBMS) cells in response to IL-1beta and tumor necrosis factor-alpha. In the present study we investigated the regulation of IL-8 gene expression by IL-1beta, osteotropic hormones, and protein kinase inhibitors in primary cultures of HBMS cells. The treatment of HBMS cells with IL-1beta increased the steady-state levels of IL-8 mRNA in a dose- and time-dependent fashion and was detectable within 1 h, reached maximal by 4 h, and remained elevated at 24 h, whereas parathyroid hormone (10(-7) and 10(-8) M) had no effect on IL-8 mRNA. Both synthetic and natural glucocorticoids dexamethasone (10(-7)-10(-10) M) and hydrocortisone (10(-6)-10(-8) M) inhibited IL-1beta-stimulated IL-8 mRNA expression. The suppressive effect of dexamethasone on IL-1beta-induced IL-8 mRNA was not observed in the presence of cycloheximide (5 microg/ml), indicating that the dexamethasone-mediated repression of IL-8 gene expression also depends on new protein synthesis. Experiments with actinomycin D demonstrated that IL-8 mRNA is long-lived and that glucocorticoids down-regulate IL-8 gene expression mainly by decreasing the mRNA stability in normal HBMS cells. Furthermore, as determined by nuclear run-on analysis, IL-1beta increased the rate of transcription of IL-8 gene and dexamethasone did not affect the IL-1beta-induced transcription of IL-8. 1-(5-Isoquinolinesulfonyl)-2-methylpiperazine, HCl (50 microM) and staurosporine (1 microM), potent inhibitors of protein kinase C, and genistein (100 microM), a specific protein tyrosine kinase inhibitor blocked IL-1beta-induced IL-8 gene expression. Because curcumin (20 microM), an inhibitor of c-jun/AP-1 and protein kinases, also blocked IL-1beta-stimulated IL-8 gene expression implicating c-JUN/AP-1 and protein phosphorylation in the induction of IL-8 gene expression by IL-1beta, we conclude that the regulation of IL-8 mRNA by IL-1beta is mediated via protein kinase-dependent signal transduction pathways. Our accumulated results have demonstrated that glucocorticoid suppression of IL-1beta-induced IL-8 mRNA occurs at the levels of post-transcription (mRNA stability) and protein synthesis.
Insulin and ghrelin: peripheral hormones modulating memory and hippocampal function

Peptide hormones, initially identified in the periphery and best known for regulation of food intake and appetite, have increasingly been shown to regulate brain functions not only within the hypothalamus but elsewhere. The hippocampus, in particular, expresses receptors for many hormones. Both insulin and ghrelin are now known to enhance hippocampal memory processes; in addition, insulin acts to increase local hippocampal metabolism and regulate synaptic plasticity, while administration of ghrelin has been shown to promote dendritic spine synaptic formation and to increase anxiety. While insulin's effects appear to be specifically within the hippocampus, ghrelin may act at a range of sites within the limbic system.
The Darwin App

What would it actually feel like to realize that the software you're using is evolving on its own? The Web extra at http://youtu.be/y2YRYtOKHyU is an audio interview in which author Brian David Johnson, prompted by a reader's submission, explores the intersection of evolution and technology with Nathan Shedroff, co-author of "Make it So," an investigation of science fiction and design.
Six Galleons for the King of Spain: Imperial Defense in the Early Seventeenth Century

In 1625, Martin de Arana built six Atlantic warships for the Spanish crown. The author traces the ships from their construction through a decade of service, incorporating a history of Spain's Golden Age. This book was awarded the Spain and America in Quincentennial Year of Discovery prize.
Genetic deficiency of NADPH oxidase does not diminish, but rather enhances, LPS-induced acute inflammatory responses in vivo.

Abstract Reactive oxygen species (ROS) and oxidative stress are thought to play a central role in the etiology of cell dysfunction and tissue damage in sepsis. However, there is limited and controversial evidence from in vivo studies that ROS mediate cell signaling processes that elicit acute inflammatory responses during sepsis. Because NADPH oxidase is one of the main cellular sources of ROS, we investigated the role of this enzyme in lipopolysaccharide (LPS)-induced acute inflammation in vivo, utilizing mice deficient in the gp91 phox or p47 phox subunits of NADPH oxidase. Age-and body weight-matched C57BL/6J wild-type (WT) and gp91 phox−/− and p47 phox−/− mice were injected ip with 50 μg LPS or saline vehicle and sacrificed at various time points up to 24 h. We found that LPS-induced acute inflammatory responses in serum and tissues were not significantly diminished in gp91 phox−/− and p47 phox−/− mice compared to WT mice. Rather, genetic deficiency of NADPH oxidase was associated with enhanced gene expression of inflammatory mediators and increased neutrophil recruitment to lung and heart. Furthermore, no protection from LPS-induced septic death was observed in either knockout strain. Our findings suggest that NADPH oxidase-mediated ROS production and cellular redox signaling do not promote, but instead limit, LPS-induced acute inflammatory responses in vivo.
The role of medication in the treatment of pathological gambling: Bridging the gap between research and practice

After reviewing the literature on the pharmacotherapy of pathological gambling, the author discusses treatment strategies and areas for future research. The clearest indication for medicating the pathological gambler is for the treatment of comorbid disorders, primarily depression, bipolar disorder, and attention deficit hyperactivity disorder. However, there are difficulties in diagnosing the dually disordered gambler. Other current pharmacological approaches involve the use of medication to treat specific symptoms, traits, or symptom clusters; to make negative affects more tolerable; and to reduce cravings. Future approaches will be directed at subgroups of gamblers. This may include genetic profiling, paired with recognition of neurotransmitter deficits, and the identification of clinical syndromes and subtypes. The author also discusses the kindling hypothesis as it may pertain to pathological gambling. The presence of kindling would make a strong case for earlier and more aggressive use of medication and for long-term maintenance to prevent relapse.
Verifiable and computable ℓ ∞ performance evaluation of ℓ 1 sparse signal recovery

In this paper, we develop verifiable and computable performance analysis of the l ∞ norms of the recovery errors for l 1 minimization algorithms. We define a family of goodness measures for arbitrary sensing matrices as a set of optimization problems, and design algorithms with a theoretical global convergence guarantee to compute these goodness measures. The proposed algorithms solve a series of second-order cone programs, or linear programs. As a by-product, we implement an efficient algorithm to verify a sufficient condition for exact l 1 recovery in the noise-free case. This implementation performs orders-of-magnitude faster than the state-of-the-art techniques. We derive performance bounds on the l ∞ norms of the recovery errors in terms of these goodness measures. We establish connections between other performance criteria (e.g., the l 2 norm, l 1 norm, and support recovery) and the l ∞ norm in a tight manner. We also analytically demonstrate that the developed goodness measures are non-degenerate for a large class of random sensing matrices, as long as the number of measurements is relatively large. Numerical experiments show that, compared with the restricted isometry based performance bounds, our error bounds apply to a wider range of problems and are tighter, when the sparsity levels of the signals are relatively low.
Effect of chronic native flow competition on internal thoracic artery grafts

Residual competitive flow from the native coronary artery has been proposed as a mechanism that reduces flow in an internal thoracic artery graft (ITA), resulting in narrowing and ultimately failure of the graft. Results from acute experiments have indicated that competitive flow from a fully patent native artery did not abolish ITA graft flow. The present study was designed to examine the consequences of dynamic flow competition between the native vessel and the ITA graft in a chronic model. Fifteen mongrel dogs underwent coronary artery bypass grafting using the pedicled left ITA anastomosed to the normal, fully patent circumflex (CFX) coronary artery. The procedure was performed through a sterile thoracotomy, without systemic cardiopulmonary bypass, using a brief local occlusion to construct the anastomosis. Intraoperatively, ITA flow was measured in situ on the chest wall, before the pedicle was mobilized. Internal thoracic artery graft and distal CFX flow were measured after the anastomosis was completed, with and without brief occlusion of the proximal CFX. Angiography was per
Electron transfer mechanism studies of cytochrome c3: pH dependence of the redox equilibria

Abstract Cytochromes c3 are tetrahaem electron transfer proteins isolated from Desulfovibrio spp. which play an important role in the metabolism of sulfur compounds and hydrogen [1]. They have a molecular weight of approx. 13,000 Daltons [1, 2]. The four haems, mesoporphyrins, are covalently bound to the polypeptide chain through thioether linkages provided by cysteinyl residues. The axial ligands are two hystidinyl residues [3, 4] and all the haems have negative, although different mid-point redox potentials [5–8]. Several physico-chemical techniques, mainly Mossbauer [9], EPR [4–7], NMR [3, 10–16], cyclic voltammetry, and different pulse polarography [6, 7], have been applied to elucidate the mechanism of electron transfer in cytochrome c3. However, the mechanism by which electrons are transferred between cytochrome c3 and other electron carriers is only poorly understood. NMR has been shown to be a suitable technique to elucidate the electron exchange mechanism of cytochrome