cssi/SciSciGPT-SciSciNet huggingface dataset:
Transient Two-Dimensional Electronic Spectroscopy: Coherent Dynamics at Arbitrary Times along the Reaction Coordinate.

Recent advances in two-dimensional electronic spectroscopy (2DES) have enabled identification of fragile quantum coherences in condensed-phase systems near the equilibrium molecular geometry. In general, traditional 2DES cannot measure such coherences associated with photophysical processes that occur at times significantly after the initially prepared state has dephased, such as the evolution of the initial excited state into a charge transfer state. We demonstrate the use of transient two-dimensional electronic spectroscopy (t-2DES) to probe coherences in an electron donor–acceptor dyad consisting of a perylenediimide (PDI) acceptor and a perylene (Per) donor. An actinic pump pulse prepares the lowest excited singlet state of PDI followed by formation of the PDI•––Per•+ ion pair, which is probed at different times following the actinic pulse using 2DES. Analysis of the observed coherences provides information about electronic, vibronic, and vibrational interactions at any time along the reaction coordinate for ion pair formation.
Meeting the Psychosocial and Rehabilitative Needs of the Visually Impaired Diabetic.

The psychosocial and visual problems of proliferating diabetic retinopathy are discussed in terms of four stages: discovery of the diagnosis, developing awareness of the diagnosis, realization of d...
High temperature oxidation and microstructural evolution of cold spray chromium coatings on Zircaloy-4 in steam environments

Abstract Oxidation kinetics and microstructural evolution of cold sprayed Cr coatings on Zircaloy-4 at 1130–1310 °C in flowing steam at atmospheric pressure have been studied. The study is aimed at understanding of the response of Cr coated Zr-alloy under a steam environment and high temperatures pertinent to design basis accidents (DBAs) and beyond design basis accidents (BDBAs) in light water reactors (LWRs). Surface morphology, microstructure, and phases of post-oxidation test samples were characterized using Scanning Electron Microscopy (SEM), x-ray diffraction (XRD), and Scanning Transmission Electron Microscopy (STEM). Growth kinetics of the Cr-oxide scale and interdiffusion layers between the Cr coating and the Zr-alloy substrate were quantified from cross-sectional SEM images. Cross-sectional analysis showed that the Cr coatings offered a 50 times reduction in oxidation rate over bare Zircaloy-4 in a 1310 °C steam environment. Oxidation kinetics at 1130 °C followed parabolic law (i.e., n ∼ 0.5 in power law kinetics) but at 1230 °C and 1310 °C the value of n was suppressed to below 0.5 possibly due to the volatilization of Cr species at the two highest temperatures. Interdiffusion at coating/substrate interface resulted in formation of a brittle Cr2Zr or Zr(Fe, Cr)2 intermetallic compound layer on the order of micrometer in thickness and scattered Cr-rich precipitates were observed well below the interface within the Zr-alloy substrate after cooling. These experimental results could provide data to LWR system simulation codes for better estimation of coping time in the event of accidents.
Amyloidosis of the bladder and association with urothelial carcinoma: report of 29 cases

Summary The association of amyloidosis with certain neoplastic processes is well known. Amyloid uncommonly occurs in relationship with other epithelial neoplasms including urothelial carcinoma. Herein, we report 29 cases of amyloidosis in the bladder, 14 of which were found in relationship to urothelial carcinoma. With institutional review board approval. We searched pathology archives for cases of amyloidosis in the bladder. Clinical, laboratory, and surgical pathology records were reviewed, and data were recorded for all cases. Diagnosis of amyloid was made by Congo red stain showing apple-green birefringence on polarization microscopy and special studies in some cases. Twenty-nine cases of amyloid were identified in bladder specimens. Presentation as a mass lesion was the most common (n = 18). Immunohistochemical subtyping done in 17 cases showed transthyretin-type (n = 10), AL (n = 3), AA (n = 1), amyloid P (n = 1), and undetermined (n = 2) types of amyloid. Eighteen (62%) cases were classified as localized primary amyloidosis and 11 (38%) as secondary manifestation of systemic amyloidosis. In 14 (48%) cases, there was an associated urothelial carcinoma: 5 urothelial carcinoma in situ, 4 low-grade noninvasive papillary urothelial carcinoma, 2 high-grade noninvasive papillary urothelial carcinoma, and 3 high-grade invasive urothelial carcinoma. Associated urothelial carcinoma was present in 4 of 7 patients with systemic amyloidosis and 10 of 18 patients with localized amyloidosis, with the difference not being statistically significant (P = .45). Amyloidosis of the bladder is rare and presents as a mucosal mass or hematuria that may mimic urothelial carcinoma. In this study, we found urothelial carcinoma occurring in 48% of the cases in association with amyloidosis, a finding not previously reported. The relationship of amyloid in the bladder and urothelial carcinoma, although likely not causal, appears to be a unique finding not frequently seen with other solid tumors.
Using the Modified Delphi Method to Develop a Tool to Assess Pediatric Residents Supervising on Inpatient Rounds.

Abstract Background Consensus about behaviors that define effective supervision by residents of more junior trainees on pediatric inpatient rounds is lacking. Objective Use modified Delphi method to develop a checklist of essential supervisory behaviors pediatric residents demonstrate while leading inpatient, non-ICU, nonspecialty teaching rounds and pilot the checklist. Design/Methods One hundred and forty-one initial candidate behaviors were identified through literature review and narrowed by local stakeholders. Forty-one behaviors were submitted to national experts identified through purposive sampling to be refined using the modified Delphi method. Participants indicated agreement with behaviors’ inclusion in the checklist and whether any were nonobservable. Measures of central tendency and dispersion were used to identify consensus with a behavior's inclusion in the next cycle. A criterion was eliminated if >25% of experts felt it was not observable. Cycles continued until consensus was reached on ≤20 behaviors. The resulting checklist was piloted at 2 hospitals. Results After 2 modified Delphi cycles, consensus was obtained on 18 behaviors for inclusion in the final checklist. These were spread across 3 subcategories: teaching, leadership, and patient safety. In the pilot, the checklist of behaviors discriminated between residents with differing levels of competency in supervising trainees on inpatient rounds. For residents who had the checklist completed by 2 faculties, there was 75% agreement in behaviors observed. Conclusion(s) Based on literature review, local stakeholder input, and consensus of national experts through the modified Delphi method, we created and piloted a checklist of observable behaviors characteristic of effective clinical supervision by pediatric residents leading trainee teams on inpatient, non-ICU, nonspecialty rounds.
Investigation of the band gaps and bowing parameter of InAs 1 − x Sb x alloys using the modified Becke-Johnson potential

The band gaps and structural properties of ${\mathrm{InAs}}_{1\ensuremath{-}x}{\mathrm{Sb}}_{x}$ alloys are investigated using both the modified Becke-Johnson exchange potential and hybrid functional calculations. A good agreement between the two approaches is observed for the alloys. The estimated value of $0.85\phantom{\rule{0.16em}{0ex}}\mathrm{eV}$ for the bowing parameter enables the use of $\mathrm{InAsSb}$ in long wavelength infrared (LWIR) applications. Furthermore, a lower limit of $0.29\phantom{\rule{0.16em}{0ex}}\mathrm{eV}$ for the bowing parameter is obtained for the structures yielding the largest band gaps, demonstrating the strong nonlinearity of the band gap versus the composition for this system.
Abstract P4-10-30: PD-L1 expression in tumor infiltrating lymphocytes (TILs) inversely correlates with androgen receptor (AR) expression in HER2-positive breast cancer

Background: Human epidermal growth factor receptor 2 (HER2)-positive breast cancer accounts for 20-30% of breast carcinomas and is associated with a poor prognosis. While anti-HER2 targeted therapies have improved outcomes within this group, a subset of these tumors eventually develop resistance urgently requiring novel therapeutic options. In addition to classic HER2+ subtype, estrogen receptor (ER)-positive and HER2-positive tumors (luminal B) are another subtype of HER2 expressing breast carcinomas which could also benefit from additional therapies. Targeting the androgen receptor (AR) pathway and the PD-L1 axis may represent potential new therapeutic strategies in breast cancer. Our group previously reported that AR expression is seen in ¾ of HER2+ carcinomas and is more common in luminal B compared to classic HER2+ tumors. In this report, we evaluated expression of PD-L1 in tumor infiltrating lymphocytes (TILs) in both classic HER2 + and Luminal B subtypes of breast carcinomas and correlated the expression of PD-L1 with AR expression in these tumors. Methods: The study population consisted of 114 patients with HER2-positive invasive breast carcinoma diagnosed from 2009-2014 at Northwestern Memorial Hospital. Electronic medical records were reviewed for patient demographics (mean age 54, range 23-80). Pathologic tumor characteristics (histologic type, size, and grade) and tumor marker profile (ER and HER2) were evaluated. Tissue microarrays were constructed (3 cores from each case to account for tumor heterogeneity) for immunohistochemical evaluation of AR and PD-L1. AR was graded as positive when at least 1% of tumor cells showed nuclear immunoreactivity. For PD-L1, the extent of staining (0%=0, 1-10%=1, 11-50%=2, and 51-100%=3) and staining intensity (0, 1+, 2+, 3+) were assessed in TILs. Then a composite score (CS) was calculated by multiplying extent and intensity results (range 0-9; 0-3=negative, 4-9=positive). Results: Of the 114 studied breast carcinoma cases, 54 were classic HER2+ tumors (47%) and 60 were luminal B (53%) tumors. Approximately 69% of classic HER2+ and 87% of luminal B cases were positive for AR. Of interest, in classic HER2+ cases, the expression of PD-L1 in TILs was inversely correlated with the expression of AR, with 82% (14/17) of AR- tumors being positive for PD-L1 in TILs compared to only 46% (17/37) of AR+ tumors with PD-L1 expression in TILs (p Citation Format: Tiansheng Shen, Jennifer L. Pincus, Kalliopi P. Siziopikou. PD-L1 expression in tumor infiltrating lymphocytes (TILs) inversely correlates with androgen receptor (AR) expression in HER2-positive breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-10-30.
Chapter 5 – OBEX

Publisher Summary This chapter deals with OBEX that provides a structured way to send data between embedded devices. OBEX was defined by IrDA and adopted by the Bluetooth SIG. The Generic Object Exchange Profile (GOEP) defines OBEX within the Bluetooth world. Many different profiles are defined on top of GOEP. For Bluetooth devices, OBEX uses the RFCOMM protocol as the transport protocol. OBEX is built on a request and response scheme. The client drives the connection by issuing requests to the server. The server can accept or reject the request using any of the HTTP response codes. CONNECT, PUT, GET, SETPATH, DELETE, CREATE EMPTY, and DISCONNECT are the valid operations that may be performed by a client. A client session begins with a CONNECT request and ends with a DISCONNECT request. OBEX also provides a mechanism for authentication. This method is different from Bluetooth authentication. OBEX authentication uses a challenge and response scheme.
Association between edentulism and cognition among people aged 50 and over

Objective: To investigate the association between edentulism and cognition in people aged 50 and over in China. Methods: Cross-sectional data was collected from the first wave of World Health Organization Study on global AGEing and adult health in China, among people aged 50 and over in China. A comprehensive cognitive test was used to assess cognitive functions, including verbal recall (VR), verbal fluency (VF), forward digit span (FDS) and backward digit span (BDS) among the subjects. Association between edentulism and cognition was examined by a two-level (individual level and community level) linear model. Results: A total of 12 843 individuals aged 50 years and over were included for analysis, with an average age of (63.0±9.3) years. The overall prevalence of edentulism was 11.0%. The edentulous adults had lower mean scores of VR (4.55), VF (10.88), FDS (6.25), BDS (2.96) and overall cognition (49.15) (P<0.001). Edentulism was negatively associated with VR (β=-0.216, 95%CI: -0.370 - -0.062), FDS (β=-0.186, 95%CI: -0.293 - -0.078) and overall cognition (β=-1.703, 95%CI: -3.025 - -0.381) after adjusted for age, sex, residence, education level, marital status, household income, co-morbidity of chronic conditions, BMI, smoking and drinking alcohol. Conclusion: Edentulism was related with lower cognition level in people aged 50 and over in China.
Solvent/Detergent-Treated Plasma in the Management of Pediatric Patients Who Require Replacement of Multiple Coagulation Factors: An Open-Label, Multicenter, Post-marketing Study.

Background: Octaplas is a solvent/detergent-treated, pooled plasma used for the management of preoperative or bleeding patients who require replacement of single or multiple coagulation factors. The aim of this post-marketing study was to collect real-world data on octaplas treatment in pediatric patients, with the primary focus being safety. Methods: This was an open-label, multicenter, phase IV study conducted in patients 2 years old, n = 13; female, n = 24) and 49 patients completed the study. Indications for the use of octaplas included planned cardiac surgery (n = 40, 80.0%), liver transplant surgery (n = 5, 10.0%) and liver dysfunction (n = 5, 10.0%). No ADRs, HFEs or treatment-related TEs and TEEs occurred during the study. Five patients had SAEs, one of which was fatal (iatrogenic injury). Other SAEs included hemorrhage, hypotension, hemorrhagic shock, coronary artery hemorrhage, intracardiac thrombus, supraventricular tachycardia, portal vein thrombosis and respiratory failure (1 each). None of the SAEs were considered to be related to octaplas. Conclusions: Results of the present study support the use of octaplas in the management of preoperative or bleeding pediatric patients who require replacement of multiple plasma coagulation factors. Clinical Trial Registration: ClinicalTrials.gov identifier: NCT02050841.
Integrative cardiovascular control in women: Regulation of blood pressure, body temperature, and cerebrovascular responsiveness

Over the past several decades, it has become increasingly clear that women have distinct cardiovascular profiles compared to men. In this review, our goal is to provide an overview of the literature regarding the influences of female sex and reproductive hormones (primarily estradiol) on mechanisms of cardiovascular control relevant to regulation of blood pressure, body temperature, and cerebral blood flow. Young women tend to have lower resting blood pressure compared with men. This sex difference is reversed at menopause, when women develop higher sympathetic nerve activity and the risk of systemic hypertension increases sharply as postmenopausal women age. Vascular responses to thermal stress, including cutaneous vasodilation and vasoconstriction, are also affected by reproductive hormones in women, where estradiol appears to promote vasodilation and heat dissipation. The influence of reproductive hormones on cerebral blood flow and sex differences in the ability of the cerebral vasculature to increase its blood flow (cerebrovascular reactivity) are relatively new areas of investigation. Sex and hormonal influences on integrative blood flow regulation have further implications during challenges to physiological homeostasis, including exercise. We propose that increasing awareness of these sex-specific mechanisms is important for optimizing health care and promotion of wellness in women across the life span.
Central Nervous System Infections in the Immunocompromised Adult Presenting to the Emergency Department.

Over the past 2 decades, the population of immunocompromised patients has increased dramatically in the United States. These patients are at elevated risk for both community-acquired and opportunistic central nervous system infections. We review the most common and serious central nervous system pathogens affecting these patients and outline a diagnostic and therapeutic approach to their management in the emergency department. We recommend a broad diagnostic evaluation, including neuroimaging and cerebrospinal fluid studies where appropriate, empiric antimicrobial therapy, and early involvement of subspecialists to provide comprehensive care for these complex patients.
Lectures on the Near-Side Ridge, Landau Hydrodynamics, and Heavy Quarkonia in High Energy Heavy-Ion Collisions

We give an introduction to three different topics that are of current interest in heavy-ion collisions. Particles associated with the near-side jet are found to exhibit a Δφ-Δη correlation in the form of a ridge in the Δη direction but a peak at Δφ ∼ 0. The experimental data support the description that the ridge particles are medium partons kicked by the jet. The measurement of the characteristics of the ridge provides a unique tool to probe the nature of the (jet parton)-(medium parton) collision and the momentum distribution of dense matter formed in the early stage of the heavy-ion collision. We find that the magnitude of the longitudinal momentum kick along the jet direction acquired by a medium parton in collision with the jet is about 1 GeV, and the early parton momentum distribution is in the form of a rapidity plateau with a thermal-type transverse momentum distribution. In the second lecture, we re-examine the validity of Landau hydrodynamics which provides a reasonable description of the space-time dynamics of the hot matter produced in high-energy heavy-ion collisions. We find that the rapidity distribution of produced particles should be more appropriately modified from Landau's result. Past successes of the Gaussian distribution in explaining experimental rapidity data can be understood, not because it is an approximation of the original Landau distribution, but because it is in fact a close representation of the modified distribution. In the final lecture, we give an introduction to the development of the potential model for quarkonia, using thermodynamical quantities obtained in lattice gauge calculations. We find that the potential model is consistent with the lattice gauge spectral function analysis, if the color-singlet heavy quark-antiquark potential is a linear combination of the color-singlet free energy F1 and internal energy U1, with coefficients that depend on the equation of state. We find that the effects of dynamical quark modifies only slightly the stability of J/ψ and the quark drip line limits possible quarkonium states with light quarks to temperatures close to, and slightly greater than, the critical phase transition temperature.
Cigar-Smoking-Cessation Interest and Experience among Black Young Adults: A Semi-Structured In-Depth Interview Investigation

Although Black/African American populations have high cigar-smoking prevalence, little is known about cigar-smoking cessation among this group. This study explored the perceptions and experiences of cigar-smoking cessation and assistance received from healthcare providers among forty Black young-adult cigar smokers (ages 21–29). Semi-structured in-depth phone interviews were transcribed and coded. Qualitative data were analyzed by using thematic analysis. Participants mostly smoked cigarillos, large cigars, and blunts. Overall, many regular cigarillo smokers reported interest in quitting eventually, while large-cigar and blunt smokers shared less interest in quitting because they perceived low harm from smoking these products. The reasons for cigar-smoking cessation were health concerns and financial constraints. Most of the participants who attempted to quit cigars did not use any cessation aids. The reasons for relapse included nicotine withdrawal, stress, and easy access. Additionally, most participants reported their healthcare providers did not ask whether they smoked cigars, and even when they knew, little assistance for cigar-smoking cessation was provided. Informing Black cigar smokers of the harm of cigar smoking and encouraging healthcare providers to screen for and assist with cigar-smoking cessation may alleviate the health burden of cigar smoking in this population.
Translational control of lipogenesis links protein synthesis and phosphoinositide signaling with nuclear division in Saccharomyces cerevisiae.

Continuously dividing cells coordinate their growth and division. How fast cells grow in mass determines how fast they will multiply. Yet, there are few, if any, examples of a metabolic pathway that actively drives a cell cycle event instead of just being required for it. Here, we show that translational upregulation of lipogenic enzymes in Saccharomyces cerevisiae increased the abundance of lipids and promoted nuclear elongation and division. De-repressing translation of acetyl CoA carboxylase and fatty acid synthase also suppressed cell cycle-related phenotypes, including delayed nuclear division, associated with Sec14p phosphatidylinositol transfer protein deficiencies, and the irregular nuclear morphologies of mutants defective in phosphatidylinositol 4-OH kinase activities. Our results show that increased lipogenesis drives a critical cell cycle landmark and report a phosphoinositide signaling axis in control of nuclear division. The broad conservation of these lipid metabolic and signaling pathways raises the possibility these activities similarly govern nuclear division in other eukaryotes. In this report, the authors show that increasing lipid synthesis promotes the division of the nucleus in yeast cells, a model eukaryotic organism. They also implicate phosphoinositide signaling in the control of nuclear division. Because lipid metabolic and signaling pathways are highly conserved, it is possible that these activities also control nuclear division in other organisms. AUTHOR SUMMARY In this report, the authors show that increasing lipid synthesis promotes the division of the nucleus in yeast cells, a model eukaryotic organism. They also implicate phosphoinositide signaling in the control of nuclear division. Because lipid metabolic and signaling pathways are highly conserved, it is possible that these activities also control nuclear division in other organisms.
Using Multiple Antibiotic Resistance and Land Use Characteristics to Determine Sources of Fecal Coliform Bacterial Pollutiion

Multiple Antibiotic Resistance (MAR) analysis and regression modeling techniques were used to identify surface water areas impacted by fecal pollution from human sources, and to determine the effects of land use on fecal pollution in Murrells Inlet, a small, urbanized, high-salinity estuary located between Myrtle Beach and Georgetown, South Carolina. MAR analysis was performed to identify areas in the estuary that are impacted by human-source fecal pollution. Additionally, regression analysis was performed to determine if an association exists between land use and fecal coliform densities over the ten-year period from 1989 to 1998. Land-use variables were derived using Geographic Information System (GIS) techniques and were used in the regression analysis.
Speculations about the QCD vacuum

Since quantum chrorc, odynamics is generally accepted as the only serious candidate for the role as the fundamental theory of the strong interactions it is important to try to obtain an understanding of the character of its ground state. Here I will try to give some indications (1) which suggest that the vacuum state may be described as a quantum liquid of gluon pairs, (2) together with the standard short wave length fluctuations present in the ordinary perturbative vacuum of quantum field theory. The size of the gluon pair wave function will be comparable to the distance between the pairs. There will also be an effective short distance repulsion between the pairs ~iich inhibits their overlap. At the same time since there is no conservation law to prevent the spontaneous creation of the pairs, and we will show that they have a negative energy, all space must be filled with them. It is these features ~ich lead to the liquid character of the state. in the first part of this talk, I will review the well-known properties of the perturbative ground state in an intuitive way. In the second part, I will discuss the intuitive and semi-quantitative estimates on which a "liquid" description of the ground state is based. In the last part, I will suggest a method on which a more systematic treatment might be based.
Efflux and the Steady State in α-Methylglucoside Transport in Escherichia coli

Abstract Efflux and the steady state in a group translocation system, the α-methylglucoside (αMG) transport system, were investigated. The maximum intracellular level of α-methylglucoside is a function of a steady state. There is no inhibition of αMG influx as the intracellular pool of αMG, and α-methylglucoside-6-phosphate (αMGP) rises. This steady state has three components: αMG influx, action of an αMGP phosphatase, and αMG efflux. The phosphatase is the rate-limiting step (half-time = 5.0 min); thus, the true efflux rate (half-time = 2.0 min) cannot be simply measured from the kinetics of αMG loss from the cell. Under our steady-state conditions the percentage of intracellular radioactivity present as αMGP was 71%. Under conditions of zero influx, after an efflux of 12 min the percentage present as αMGP fell to 55%. However, when fluoride was present during the efflux period, the percentage of the sugar as αMGP increased to about 85%. Fluoride greatly inhibits both influx and phosphatase activity (half-time = 50 min). The efflux of αMG from the cell is apparently also fluoride-sensitive but to a lesser extent (half-time = 4.1 min). These data are summarized in a model describing the three components of the steady-state and effect of fluoride.
History of psychotherapeutic intervention in cancer patients

Several important aspects of the history of psychotherapeutic interventions in cancer patients, such as the historical role of the “cancer personality,” the change in the conceptualization of the mind-body relationship and the influence of medical progress and social developments, are discussed.
Influence of drainage basin topography and elevation on carbon dioxide and methane supersaturation of stream water

The partial pressures of CO2 (pCO2) andCH4 (pCH4) in streams are not only governed byinstream processes, but also by transformations occurring in soil andgroundwater ecosystems. As such, stream water pCO2 andpCH4 can provide a tool to assess ecosystem respiration andanaerobic metabolism throughout drainage basins. We conducted three surveyssampling the gas content of streams in eastern Tennessee and western NorthCarolina to assess factors regulating ecosystem metabolism in catchmentswith contrasting geomorphologies, elevations and soil organic matterstorage. In our first survey, the influence of drainage basin geomorphologyon ecosystem respiration was examined by sampling streams drainingcatchments underlain by either shale or dolomite. Geomorphology isinfluenced by geology with shale catchments having shallower soils, broader,unconstrained valley floors compared with dolomite catchments.pCO2 varied little between catchment types but increased froman average of 3340 ppmv in spring to 9927 ppmv in summer or 9.3 and 28 timesatmospheric equilibrium (pCO2(equilib)), respectively. Incontrast, pCH4 was over twice as high in streams drainingshale catchments (306 ppmv; pCH4(equilib) = 116) compared withmore steeply incised dolomite basins (130 ppmv; pCH4(equilib)= 51). Using the ratio of pCH4:pCO2 as an indexof anaerobic metabolism, shale catchments had nearly twice as muchanaerobiosis (pCH4:pCO2 = 0.046) than dolomitedrainages (pCH4:pCO2 = 0.024). In our secondsurvey, streams were sampled along an elevational gradient (525 to 1700 m)in the Great Smoky Mountains National Park, USA where soil organic matterstorage increases with elevation. pCO2 did not vary betweenstreams but increased from 5340 ppmv (pCO2(equilib) = 15) to8565 ppmv (pCO2(equilib) = 24) from spring to summer,respectively. During spring pCH4 was low and constant acrossstreams, but during summer increased with elevation ranging from 17 to 2068ppmv (pCH4(equilib) = 10 to 1216). The contribution ofanaerobiosis to total respiration was constant during spring(pCH4:pCO2 = 0.017) but during summer increasedwith elevation from 0.002 at 524 m to 0.289 at 1286 m. In our last survey,we examined how pCO2 and pCH4 changed withcatchment size along two rivers (ca. 60 km stretches in both riverscorresponding to increases in basin size from 1.7–477km2 and 2.5–275 km2). pCO2and pCH4 showed opposite trends, with pCO2decreasing ca. 50% along the rivers, whereas pCH4roughly doubled in concentration downstream. These opposing shifts resultedin a nearly five-fold increase of pCH4:pCO2along the rivers from a low of 0.012 in headwaters to a high of 0.266 65-kmdownstream. pCO2 likely declines moving downstream asgroundwater influences on stream chemistry decreases, whereaspCH4 may increase as the prevalence of anoxia in riversexpands due to finer-grained sediments and reduced hydrologic exchange withoxygenated surface water.
Computer simulation of nonequilibrium processes

The underlying concepts of nonequilibrium statistical mechanics, and of irreversible thermodynamics, will be described. The question at hand is then, How are these concepts to be realized in computer simulations of many-particle systems? The answer will be given for dissipative deformation processes in solids, on three hierarchical levels: heterogeneous plastic flow, dislocation dynamics, and molecular dynamics. Application to the shock process will be discussed.
No Second Chance at Making a Good First Impression: Peril and Possibility in the Campus Visit

Scott Keeter is professor of public and international affairs and former department chair at George Mason University. He is on leave from the university and is serving as associate director of the Pew Research Center for the Public and the Press. He was the first of three finalists to visit campus for an interview,l and we were excited. His CV was impressive, his recommendations were strong, and he was pleasant and poised on the phone. The faculty had assembled for his job talk, and we expected a winner. An hour later we couldn't wait to escape. The candidate had read us his paper virtually word-for-word-while rarely looking up to meet our plaintive eyes. He took up almost the entire hour with his own presentation, leaving us no time for questions, but by then we had only one question in mind: How had this disaster occurred? How had such a promising candidate shot himself out of contention? Over the last three years the two of us have had the opportunity to interview 31 faculty candidates on campus. Our department has been fortunate to add new programs and garner supplemental resources (at least when times were flush). To a 26-person department we have added 13 new colleagues. Doing so, though, has required 13 search committees and nearly three dozen campus
Thermal Sensitivity Analysis of a Luminescent Photoelastic Coating

This paper presents results from a thermal sensitivity study of a luminescent photoelastic coating. The investigation is part of larger research program to integrate luminescence sensing for strain measurement and health monitoring in civil, automotive and aerodynamic applications. Luminescent photoelasticity is a new approach to measure mechanically induced stress and/or strain, and corresponding principal directions on structural components. The technique incorporates a luminescent dye that partially preserves the stress-modified polarization state within a birefringent coating and provides high emission signal strength at oblique surface orientations. The optical strain response of the coating is a nonlinear function of the maximum shear strain in the plane perpendicular to the propagation of light. Several parameters may affect the strain response including luminescent polarization efficiency, optical sensitivity, coating absorptivity and effective excitation-emission wavelength. The temperature dependency of these parameters is important to characterize if the technique is extended to high-temperature or cyclic-temperature environments. A small thermal chamber was constructed with open optical access to test coated cantilevered specimens under a linearly varying bending stress. Results show that the optical strain response decreases as temperature increases. Over a temperature range spanning from 24 °C to 92 °C, the optical strain response decreased by 77%. Most of the percentage drop occurred between 35 °C and 80 °C, with relatively constant response for temperatures lower and higher. The primary source of the temperature dependency is the coating sensitivity coefficient which is a function of the modulus of elasticity. Higher strains tended to delay the transition, indicating strain-temperature coupling in the optical sensitivity coefficient.
Leibniz Algebras and Lie Algebras

This paper concerns the algebraic structure of finite-dimensional complex Leibniz algebras. In particular, we introduce left central and symmetric Leibniz algebras, and study the poset of Lie subalgebras using an associative bilinear pairing taking values in the Leibniz kernel.
Blood-retinal barrier breakdown following experimental retinal ischemia and reperfusion

The purpose of this study was to examine the effects of acute ischemia and reperfusion on blood-retinal barrier (BRB) function in the rabbit eye. Hydrostatic pressure (140 mmHg) was used to create total retinal ischemia for intervals of 20, 40, 60, 80 or 100 min in the rabbit eye. The location, size and permeability-surface-area product normalized to the area of retinal leakage (PS') of ischemia-induced BRB lesions were then measured using contrast-enhanced magnetic resonance imaging (MRI) after various intervals of reperfusion. Diffuse outer BRB leakage occurred in most eyes subjected to 80 or 100 min of ischemia. A posterior region of outer BRB sparing was found in eyes that underwent lesser durations of ischemia. On day 1 after retinal ischemia, a linear relationship was found between mean PS' and duration of ischemia for periods of ischemia between 20 and 100 min [slope: 5·65 × 10−6 to 5·96 × 10−6 cm min−1 (min ischemia)−1; r2 ⩾ 0·69]. Lesion size also increased between 20 and 100 min of ischemia. In a longitudinal study, eyes exposed to 60 min of ischemia showed a decrease in PS' and a lesion size over an 8-week period of observation. However, leakage was still present on post-ischemia day 57 in two of three eyes examined. Data obtained in these experiments are expected to prove useful in future studies aimed at understanding how BRB damage relates to neuroretinal damage after ischemia-reperfusion injury.
Financial Planning for Dairy Herd Expansions

Abstract Many dairymen are expanding or modernizing their dairy farm businesses. Dairy farm expansion usually involves a number of changes in many areas of the farm business resulting in the need for more detailed data on costs and returns. Computer programs have been developed to simplify the task of forecasting effects of proposed farm changes. These computer programs help (1) to motivate farmers to state systematically some crucial assumptions about planned changes, (2) to enable dairymen to examine the consequences of those assumptions to see if the changes appear financially feasible and desirable, and (3) to provide benchmark projections for determining if selected business changes are going according to plans. Use of the new programs should help dairymen develop new skills in business planning and in acquiring and controlling the use of credit. These skills are increasingly as important as the production skills at which many dairymen excel.
Effects of Electrochemistry on Surface Roughness during Chemical-Mechanical Polishing of Copper

In this research, we investigated the electrochemical behavior of copper (Cu) surfaces during chemical-mechanical polishing (CMP) with alumina containing slurries. The variation of pH and the percent of oxidizer were tested against impressed anodic and cathodic potentials. The polarization curves as well as potential and current values were measured in order to investigate the effects of electrochemical interactions during polishing. The polishing performance was evaluated through friction, wear, and surface quality. Surface characterization was conducted using an atomic force microscope. The areas scanned contained surfaces having different post-CMP surface chemistry. In such, the electrochemical, chemical, and mechanical action could be revealed and compared in situ and simultaneously. Research results showed that in acidic environment, the low pH dominated the surface roughness over oxidizer and anodic current. At high pH, however, oxidizer and anodic current played important roles. As a result, an optimized polishing condition was proposed.
Modeling Heteroscedasticity in Daily Foreign-Exchange Rates

This article estimates autoregressive conditionally heteroscedastic (ARCH) and generalized ARCH (GARCH) models for five foreign currencies, using 10 years of daily data, a variety of ARCH and GARCH specifications, a number of nonnormal error densities, and a comprehensive set of diagnostic checks. It finds that ARCH and GARCH models can usually remove all heteroscedasticity in price changes in all five currencies. Goodness-of-fit diagnostics indicate that exponential GARCH with certain nonnormal distributions fits the Canadian dollar extremely well and the Swiss franc and the deutsche mark reasonably well. Only one nonnormal distribution fits the Japanese yen reasonably well. None fit the British pound.
The sudden experience of the computer

The experience of computer use can be productively articulated with concepts developed in the phenomenological tradition of philosophy. Building on the insights of classical phenomenologists, Ihde has advanced a sophisticated view of the ways humans relate to technology. I review and expand on his notions of “technological mediation,” “embodiment,” and “multistability,” and apply them to the experience of computer interface. In particular, I explore the experience of using a computer that fails to work properly. A revealing example is the experience of a user who suddenly and unexpectedly encounters a slowly-loading webpage while using the Internet. This phenomenological framework provides an account of the ways a suddenly failing technology changes our relationships to the device, to the world, and to ourselves, and it also suggests how this experience can be usefully reconceptualized.
Control of Lymphocytic Choriomeningitis Virus Infection in Granzyme B Deficient Mice

We have investigated whether granzyme B (GzmB) is required for effective cytotoxic T lymphocyte (CTL) mediated control of lymphocytic choriomeningitis virus (LCMV) infection. Clearance of LCMV from tissues of GzmB-deficient (GzmB(-)) mice following intraperitoneal infection with LCMV was impaired compared with control mice; however, the virus was ultimately eliminated. The impaired clearance of LCMV in GzmB(-) mice was not due to a deficiency in the generation of LCMV-specific T cells. In addition, CTL from LCMV-infected GzmB(-) mice efficiently lysed virus-infected cells in vitro, but were deficient in their ability to induce rapid DNA fragmentation in target cells. We examined whether the development of protective immunity against intracranial (i.c.) rechallenge with LCMV was compromised in GzmB- mice. We found that clearance of LCMV from the brain following secondary i.c. infection also was slower in the absence of GzmB; however, the virus was ultimately eliminated and the mice survived. Our data indicate that clearance of LCMV is delayed in the absence of GzmB expression, but that other CTL effector molecules can compensate for the absence of this granule constituent in vivo. (C) 2002 Elsevier Science (USA).
Catheter-related sepsis complicating long-term, tunnelled central venous dialysis catheters: Management by guidewire exchange

Standard therapy of catheter-related sepsis of long-term, tunnelled, silicone dialysis catheters is catheter removal, parenteral antibiotics, and catheter replacement in a new venous site after documented clearing of bacteremia. This leads to loss of future venous access sites. Thirteen consecutive cases of dialysis catheter-related sepsis in 10 patients successfully managed by guidewire exchange with preservation of the same central venous access site are reported. Although the most common cause of catheter sepsis in this series was coagulase-negative staphylococcus, guidewire exchange also was successful in cases due to gram-negative rods and yeast. To preserve future venous access sites in the chronic hemodialysis population, long-term, tunnelled dialysis catheter-related sepsis should be managed by a short course of parenteral antibiotics and by changing the catheter over a guidewire using the same venous insertion site.
Resonance Raman Structural Evidence that the Cis-to-Trans Isomerization in Rhodopsin Occurs in Femtoseconds

Picosecond time-resolved resonance Raman spectroscopy is used to probe the structural changes of rhodopsin's retinal chromophore as the cis-to-trans isomerization reaction occurs that initiates vision. Room-temperature resonance Raman spectra of rhodopsin's photoproduct with time delays from −0.7 to 20.8 ps are measured using 2.2 ps, 480 nm pump and 1.5 ps, 600 nm probe pulses. Hydrogen-out-of-plane (HOOP) modes at 852, 871, and 919 cm-1, fingerprint peaks at 1272, 1236, 1211, and 1166 cm-1, and a broad red-shifted ethylenic band at 1530 cm-1 are present at the earliest positive pump−probe time delay of 0.8 ps, indicating that the chromophore is already in a strained, all-trans configuration. Kinetic analyses of both the HOOP and ethylenic regions of the photoproduct spectra reveal that these features grow in with fast (∼ 200 fs) and slow (∼ 2−3 ps) components. These data provide the first structural evidence that photorhodopsin has a thermally unrelaxed, torsionally strained all-trans chromophore within ...
The friction and wear behavior of polyoxymethylene in connection with joint replacement

Abstract The wear behavior of polyoxymethylene (Delrin 150) has been studied up to surface pressures of 1200 Ib in−2 using a thrust-washer testing machine. Delrin has the advantages of higher hardness and lower creep than the currently widely used material ultrahigh molecular weight polyethylene (UHMWPE). In contrast to UHMWPE, the wear of Delrin depends on the type of liquid environment used. The wear of Delrin is lower than that of UHMWPE if tests are carried out in plasma; in water the wear of Delrin is much higher than that of UHMWPE.
LC Science Tracer Bullet: An Index

Published by the Science and Technology Division of the Library of Congress since 1972, the Tracer Bullet series is an underused reference source available in many library and government documents collections. The Tracer Bullets cover a wide variety of subjects in the natural and physical sciences and technology. Each one is devoted to a specific topic and is designed “to help a reader begin to locate published material on a subject about which he or she has only general knowledge.” Developed in the style of a library pathfinder, each explores the resources available, listing texts, handbooks, encyclopedias, dictionaries, bibliographies, government documents, and journal articles. Addresses and telephone numbers of relevant organizations are also included as are appropriate Library of Congress subject headings to use in locating additional material.
Thermally induced DNA.RNA hybrid to G-quadruplex transitions: possible implications for telomere synthesis by telomerase.

Telomerase is a specialized reverse transcriptase that contains its own RNA template for synthesis of telomeric DNA [Greider, C. W., & Blackburn, E. H. (1989) Nature 337, 331-337; Shippen-Lentz, D., & Blackburn, E. H. (1990) Science 247, 546-552]. The activity of this ribonucleoprotein enzyme has been associated with cancer cells [Kim et al. (1994) Science 266, 2011-2015] and is thus a potential target for anticancer chemotherapy. Telomeric DNA.RNA hybrids are important intermediates in telomerase function and form after extension of the growing telomere on the telomerase RNA template. Translocation is a critical step in telomerase function and consists of unwinding of the telomeric DNA.telomerase RNA hybrid followed by repositioning of the 3'-end of the extended telomere. A central question in telomerase function is how translocation of the extended telomere occurs in the absence of ATP or GTP. It has been hypothesized that unwinding of the telomeric hybrid may be facilitated by the formation of stable hairpins or G-quadruplexes by the telomere product (i.e., a hybrid to G-quadruplex transition) and that this may provide at least part of the driving force for translocation [Shippen-Lentz & Blackburn, 1990; Zahler et al. (1991) Nature 350, 718-720]. However, so far there has been no effort aimed at examining the possibility that a hybrid/G-quadruplex equilibrium can occur and to what extent this equilibrium depends on buffer and concentration conditions. Examination of these transitions may provide insight into telomerase function and may also provide clues for the development of anti-telomerase agents. Using a model system consisting of the DNA.RNA hybrid d(GGTTAGGGTTAG).r(cuaacccuaacc), we present evidence that a thermally induced transition of telomeric DNA.RNA hybrid to G-quadruplex can occur under certain conditions. These results provide support for the hypothesis that G-quadruplex formation by the telomere product may in fact regulate telomerase function at the translocation step (Zahler et al., 1991) and suggest an Achilles' heel for indirectly targeting telomerase. Thus, on the basis of the insight gained from the present studies and the results of Zahler et al. (1991), we propose that ligands that selectively bind or cleave G-quadruplex structures may modulate telomerase processivity.
AMPK stimulation increases LCFA but not glucose clearance in cardiac muscle in vivo.

AMP-activated protein kinase (AMPK) independently increases glucose and long-chain fatty acid (LCFA) utilization in isolated cardiac muscle preparations. Recent studies indicate this may be due to ...
Guerrillas, drugs and peasants: The rational peasant and the war on drugs in Peru

Coca eradication programmes in Peru are undermined by the interaction of cocaine economics and insurgent politics. Coca cultivators can earn far more from the illegal market in coca than from any legal crop and government efforts to eradicate coca production create a political space in which Sendero Luminoso guerrillas can cultivate popular support by protecting coca cultivators from law‐enforcement agents and Colombian traffickers. We use a model of peasant decision‐making to assess the impact of crop eradication, crop substitution and drug interdiction strategies on the economic behaviour and political loyalties of Peruvian coca cultivators. We use the model to assess the likelihood that even successful anti‐drug programmes may destabilize the Peruvian government by generating popular support for Sendero Luminoso.