cssi/SciSciGPT-SciSciNet huggingface dataset:
Early Anticoagulation Bridging to Therapeutic International Normalized Ratio after Left Ventricular Assist Device Implantation is Not Associated with Thromboembolic and Bleeding Complications: A Systematic Review and Meta-Analysis

Purpose Thromboembolism (TE) is common after left ventricular assist device (LVAD) implantation and early anticoagulation (AC) bridging to therapeutic international normalized ratio (INR) has been widely implemented to prevent this complication. However, some studies suggested that no early AC bridging after LVAD implantation decreases bleeding complications without increase in incidence of TE. This meta-analysis aimed to evaluate the association between early AC bridging after LVAD implantation and incidence of TE and bleeding complications. Methods We performed a comprehensive literature search through September 2018 using MEDLINE and EMBASE. Included studies were prospective or retrospective cohort studies that compared the incidence of TE and bleeding in LVAD patients with and without early AC bridging to therapeutic INR. We calculated pooled odds ratio (OR) with 95% confidence intervals (CI) and I2 statistic using the random-effects model. Results Six studies were included in this meta-analysis. All patients had continuous-flow LVADs implanted. TE events were reported in 6 studies involving 897 patients (611 with bridging, 286 without bridging). Bleeding complications were reported in 4 studies involving 623 patients (405 with bridging, 218 without bridging). Median follow-up was 3.5 months. There was no association between AC bridging and incidence of TE (RR: 0.68; 95% CI: 0.41-1.12, I2=0%) and bleeding complications (RR: 0.98; 95% CI: 0.61-1.57, I2=32%) (Figure). Conclusion Our meta-analysis suggests that early AC bridging to therapeutic INR after LVAD implantation is not associated with decreased TE and increased bleeding complications. Controlled trials are warranted to further investigate the utility of early AC bridging after LVAD implantation in patients at high risk for TE complications.
Evaluating hours of sleep and perceived stress on dietary cognitive restraint in a survey of college students.

The objective of this study was to examine associations of sleep quality and quantity, food security, and physical activity with eating behaviors that may be associated with college weight gain. Pa...
Outcomes of sirolimus regimens in 65-year-old and older kidney transplant recipients: a registry-based observational study

In large observational studies of adult kidney transplant recipients (KTRs) where older adults (65 years old and older) were not well represented, the mammalian target of rapamycin inhibitors (mTOR inhibitors) has poorer outcomes than the standard tacrolimus–mycophenolate–steroids (TAC–MPA–S) regimen. We conducted this study to compare the outcomes of regimens containing the common mTOR inhibitor, sirolimus (SRL) against TAC–MPA–S in older adult KTRs. Using the 2000–2016 Scientific Registry of Transplant Recipients, Cox multivariable regression models were conducted to analyze the patient and graft outcomes associated with regimens containing SRL, steroids (S) and cyclosporine (CSA), tacrolimus (TAC), or mycophenolate (MPA) vs. the standard (TAC–MPA–S) regimen in older adult KTRs. Included in the analysis were 15,008 (95.19%) older adult KTRs on standard (TAC–MPA–S) regimen, 242 (1.53%) on SRL–MPA–S, 300 (1.90%) on SRL–TAC–S, and 217 (1.38%) on SRL–CSA–S. Compared with the standard regimen, the adjusted risks of all-cause death and overall graft loss over a maximum 5-year follow-up were highest with SRL–MPA–S, intermediate with SRL–TAC–S and not significantly different with SRL–CSA–S. The adjusted risks of all-cause death and overall graft loss were modified by a pre-transplant history of malignancy in older adult KTRs on SRL–TAC–S, not in those on SRL–MPA–S or SRL–CSA–S. In older adult kidney transplant recipients, SRL–TAC–S or SRL–MPA–S, but not SRL–CSA–S is associated with higher risks of death and allograft loss than standard TAC–MPA–S regimen and a pre-transplant malignancy history worsens these risks in patients on SRL–TAC–S. Confirmation of our findings by a prospective randomized trial is needed before translation into clinical practice can be recommended.
Surrogate Decision Making for Children: Who Should Decide?

Objective To identify caregivers' views on preferred surrogate decision makers for their children. Study design A respondent-anonymous survey was distributed to a convenience sample of adults who accompanied a child to general and subspecialty pediatric care at 2 different institutions or were at the bedside of a child in the pediatric intensive care unit at a third institution in Chicago. Results We collected 462 valid surveys. The average age of the legal guardian and accompanying child was 36.8 years and 6.6 years, respectively. Most legal guardians designated “other parent with legal authority” as their first choice surrogate decision maker (70%). Respondent's sex, respondent's age, child's age, and child's ethnicity had no effect on first choice surrogate decision maker. “Other parent with legal authority” was less likely to be first choice surrogate if respondents had Medicaid insurance, less than a college degree, or lived in a non-nuclear household (P Conclusions A surrogacy priority ladder for minors needs to include relatives who are often not included in state surrogacy statutes (eg, grandparents, aunts and uncles). The most popular surrogacy ladder will not be ideal for many families. Parents need to be informed and empowered to choose alternate surrogates, and documented preferences must be easily and widely accessible.
Reorientation of antiferromagnetism in cobalt doped FeSn

FeSn is an itinerant antiferromagnet that hosts electronic Dirac states and ordered magnetic moments lying within its Fe Kagome-lattice planes. We present magnetization measurements of single crystals of $({\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x})\text{Sn}$, revealing the evolution and suppression of this magnetic order with Co substitution. We interpret the dramatic changes in magnetic anisotropy to indicate a reorientation of the moments from perpendicular to parallel to the hexagonal $c$ axis and confirm this with neutron diffraction. It has been proposed that the Dirac nodes observed in FeSn should become gapped if the moments rotate as our data suggests. We identify Co-substituted compositions that adopt both antiferromagnetic configurations at different temperatures. This system provides a unique opportunity to study how the details of magnetic order impact Dirac electron states.
Radiation-induced changes to bone composition extend beyond periosteal bone

Abstract Background Cancer patients receiving radiotherapy for soft tissue sarcomas are often at risk of post-irradiation (post-RTx) bone fragility fractures, but our understanding of factors controlling radiation-induced bone injury is limited. Previous studies have evaluated post-RTx changes to cortical bone composition in the periosteum of irradiated tibiae, but have not evaluated effects of irradiation in deeper tissues, such as endosteal or mid-cortical bone, and whether there are differential spatial effects of irradiation. In this study, we hypothesize that post-RTx changes to cortical bone composition are greater in endosteal compared to mid-cortical or periosteal bone. Methods A pre-clinical mouse model of limited field hindlimb irradiation was used to evaluate spatial and temporal post-RTx changes to the metaphyseal cortex of irradiated tibiae. Irradiation was delivered unilaterally to the hindlimbs of 12-wk old female BALB/cJ mice as 4 consecutive daily doses of 5 Gy each. RTx and non-RTx tibiae were obtained at 0, 2, 4, 8, and 12 wks post-RTx (n = 9 mice/group/time). Raman spectroscopy was used to evaluate spatial and temporal post-RTx changes to cortical bone composition in age-matched RTx and non-RTx groups. Results Significant early spatial differences in mineral/matrix and collagen crosslink ratios were found between endosteal and periosteal or mid-cortical bone at 2-wks post-RTx. Although spatial differences were transient, mineral/matrix ratios significantly decreased and collagen crosslink ratios significantly increased with post-RTx time throughout the entire tibial metaphyseal cortex. Conclusions Irradiation negatively impacts the composition of cortical bone in a spatially-dependent manner starting as early as 2-wks post-RTx. Long-term progressive post-RTx changes across all cortical bone sites may eventually contribute to the increased risk of post-RTx bone fragility fractures.
Comparison of Social Media, Syndromic Surveillance, and Microbiologic Acute Respiratory Infection Data: Observational Study.

Background: Internet data can be used to improve infectious disease models. However, the representativeness and individual-level validity of internet-derived measures are largely unexplored as this requires ground truth data for study. Objective: This study sought to identify relationships between Web-based behaviors and/or conversation topics and health status using a ground truth, survey-based dataset. Methods: This study leveraged a unique dataset of self-reported surveys, microbiological laboratory tests, and social media data from the same individuals toward understanding the validity of individual-level constructs pertaining to influenza-like illness in social media data. Logistic regression models were used to identify illness in Twitter posts using user posting behaviors and topic model features extracted from users’ tweets. Results: Of 396 original study participants, only 81 met the inclusion criteria for this study. Of these participants’ tweets, we identified only two instances that were related to health and occurred within 2 weeks (before or after) of a survey indicating symptoms. It was not possible to predict when participants reported symptoms using features derived from topic models (area under the curve [AUC]=0.51; P=.38), though it was possible using behavior features, albeit with a very small effect size (AUC=0.53; P≤.001). Individual symptoms were also generally not predictable either. The study sample and a random sample from Twitter are predictably different on held-out data (AUC=0.67; P≤.001), meaning that the content posted by people who participated in this study was predictably different from that posted by random Twitter users. Individuals in the random sample and the GoViral sample used Twitter with similar frequencies (similar @ mentions, number of tweets, and number of retweets; AUC=0.50; P=.19). Conclusions: To our knowledge, this is the first instance of an attempt to use a ground truth dataset to validate infectious disease observations in social media data. The lack of signal, the lack of predictability among behaviors or topics, and the demonstrated volunteer bias in the study population are important findings for the large and growing body of disease surveillance using internet-sourced data.
Creating a Simple C Program, Compiling, and Executing It

In this initial chapter, the reader will learn how to download, install and use the Code::Blocks Integrated Development Environment. The reader will then write, compile and run his/her first C program. The chapter also covers the basic anatomy of a C program that includes the main() function, pre-processor directives, and comment lines. After executing this chapter, the reader should be able to write very simple C programs in Code::Blocks.
Ion-molecule interactions enable unexpected phase transitions in organic-inorganic aerosol

Atmospheric aerosol particles are commonly complex, aqueous organic-inorganic mixtures, and accurately predicting the properties of these particles is essential for air quality and climate projections. The prevailing assumption is that aqueous organic-inorganic aerosols exist predominately with liquid properties and that the hygroscopic inorganic fraction lowers aerosol viscosity relative to the organic fraction alone. Here, in contrast to those assumptions, we demonstrate that increasing inorganic fraction can increase aerosol viscosity (relative to predictions) and enable a humidity-dependent gel phase transition through cooperative ion-molecule interactions that give rise to long-range networks of atmospherically relevant low-mass oxygenated organic molecules (180 to 310 Da) and divalent inorganic ions. This supramolecular, ion-molecule effect can drastically influence the phase and physical properties of organic-inorganic aerosol and suggests that aerosol may be (semi)solid under more conditions than currently predicted. These observations, thus, have implications for air quality and climate that are not fully represented in atmospheric models.
Abstract 14172: Impact of Sex on Survival With Preserved Neurologic Function Following Out-of-Hospital Cardiac Arrest

Introduction: Females experience worse survival than males following out-of-hospital cardiac arrest (OHCA). Proposed explanations include previous observations that females less often have an initi...
Ferumoxytol-enhanced magnetic resonance angiography provides comparable vascular conspicuity to CT angiography in dogs with intrahepatic portosystemic shunts.

Computed tomography angiography (CTA) is currently the gold standard imaging modality for anatomically characterizing canine hepatic vascular anomalies; with conventional, gadolinium-enhanced MR angiography being less frequently utilized. However, both imaging modalities are limited by a brief, first pass peak of contrast medium in the vasculature that necessitates precisely timed image acquisition. A long-acting purely intravascular magnetic resonance imaging (MRI) contrast agent, ferumoxytol, offers the potential to reduce complexity of magnetic resonance angiography (MRA) protocol planning by ensuring diagnostic contrast medium concentration in all the vessels that are targeted for imaging. Aims of this prospective, pilot, methods comparison study were to develop an optimized MRA protocol using ferumoxytol in dogs with hepatic vascular anomalies, perform a dose escalation trial to compare image quality with four-dose regimens of ferumoxytol, and compare accuracy of vascular anatomic depiction based on the gold standard of CTA. Six dogs (10.7-36.1 kg) with portosystemic shunts (four intrahepatic left divisional shunts and two intrahepatic right divisional shunts) were recruited for inclusion in the study. A dose-escalation trial was performed to compare image quality at four incremental dose levels of ferumoxytol (1, 2, 3, and 4 mg/kg) and to compare the accuracy of vascular anatomic detection to CTA. Ferumoxytol contrast-enhanced MRA (CE-MRA) at 4 mg/kg provided similar conspicuity of normal and abnormal vasculature compared to CTA with a minimal decrease in spatial resolution. Findings indicated that ferumoxytol holds promise for comprehensive, single breath hold CE-MRA of all abdominal vessels in dogs with portosystemic shunts. Background information provided in this study can be used to support development of other future applications such as intracranial and cardiac MRA, real-time imaging, flow quantification, and potentially sedated MRI imaging.
Association between biopsy method and development of peritoneal metastases in perihilar cholangiocarcinoma.

Abstract Background In patients with perihilar cholangiocarcinoma (PHC), there is concern that transperitoneal (TP) biopsy may seed tumor in the peritoneal cavity, increasing risk of peritoneal metastases (PM). Methods A retrospective review of patients undergoing surgery for PHC (1991–2014) was performed. Clinicopathologic characteristics and incidence of PM at the time of index surgery, and one and two years after surgery were compared in patients who did vs. did not undergo TP biopsy. Results Among 262 patients who underwent surgery, 3 7 had undergone TP biopsy, and 225 had undergone intraluminal biopsy or had no biopsy. No differences in demographic or clinicopathologic characteristics were noted between groups. The incidence of PM at surgery was not significantly different between TP and non-TP biopsy patients (5.4% vs. 7.6%, p > 0.9). Among 243 patients who did not have PM at surgery, the cumulative incidence of PM in the TP and non-TP biopsy groups were not different at one year (11.4% [95%CI 3.5–24.4] vs. 10.8% [95%CI 7.0–15.5]) or two years (20.3% [95%CI 8.7–35.2] vs. 20.1% [95%CI 14.9–25.9]) (p = 0.7). Discussion Although PM commonly occurs in patients with PHC, TP biopsy was not associated with higher incidence of PM at surgery or at one or two years after surgery.
TRAGEN: a synthetic trace generator for realistic cache simulations

Traces from production caching systems of users accessing content are seldom made available to the public as they are considered private and proprietary. The dearth of realistic trace data makes it difficult for system designers and researchers to test and validate new caching algorithms and architectures. To address this key problem, we present TRAGEN, a tool that can generate a synthetic trace that is "similar" to an original trace from the production system in the sense that the two traces would result in similar hit rates in a cache simulation. We validate TRAGEN by first proving that the synthetic trace is similar to the original trace for caches of arbitrary size when the Least-Recently-Used (LRU) policy is used. Next, we empirically validate the similarity of the synthetic trace and original trace for caches that use a broad set of commonly-used caching policies that include LRU, SLRU, FIFO, RANDOM, MARKERS, CLOCK and PLRU. For our empirical validation, we use original request traces drawn from four different traffic classes from the world's largest CDN, each trace consisting of hundreds of millions of requests for tens of millions of objects. TRAGEN is publicly available and can be used to generate synthetic traces that are similar to actual production traces for a number of traffic classes such as videos, social media, web, and software downloads. Since the synthetic traces are similar to the original production ones, cache simulations performed using the synthetic traces will yield similar results to what might be attained in a production setting, making TRAGEN a key tool for cache system developers and researchers.
The Four Deaths of Acorn Whistler: Telling Stories in Colonial America. By Joshua Piker. (Cambridge, MA: Harvard University Press, 2013. Pp. i, 310. $29.95.)

The author of this book skillfully uses a 1752 attack by a party of Creeks on a group of Cherokee diplomats on the outskirts of Charleston and the subsequent execution of a Creek man named Acorn Wh...
Oxytetracycline-nystatin in the prevention of candidal vaginitis

Abstract A double-blind, randomized, crossover study of oxytetracycline versus oxytetracycline plus nystatin was carried out in 51 female volunteers susceptible to vaginal moniliasis. Forty-nine patients completed all phases of the study with 10 cases of culture-confirmed monilial vaginitis having occurred during the study. Nine of these patients developed culture-confirmed monilial vaginitis while on oxytetracycline and only one patient developed vaginitis while on the combination drug. This was highly statistically significant (p > 0.05). Other findings of this study include a positive statistical correlation between monilial vaginitis and the use of oral contraceptives and a decrease in stool monilial counts while on the combination drug as compared to oxytetracycline alone.
REVIEW: America Beyond Capitalism: Reclaiming Our Wealth, Our Liberty, and Our Democracy. BY GAR ALPEROVITZ. Hoboken, NJ: John Wiley. Cloth, $24.95. 336 pages.

(2005). REVIEW: America Beyond Capitalism: Reclaiming Our Wealth, Our Liberty, and Our Democracy. BY GAR ALPEROVITZ. Hoboken, NJ: John Wiley. Cloth, $24.95. 336 pages. Challenge: Vol. 48, No. 2, pp. 133-136.
Prescription coverage in indigent patients affects the use of long-acting opioids in the management of cancer pain.

Purpose We tested the hypothesis that prescription coverage affects the prescribing of long-acting opiates to indigent inner city minority patients with cancer pain.
Energy Use Intensity Estimation Method Based on Façade Features

Abstract In the U.S., over 72% of the total generated power is consumed by commercial and residential buildings. Among a building's envelope, system, and control, which significantly influence the building's energy performance, facade is a major parametric element that accounts for 70% of its energy performance. Compared with the internal mechanical system and operation schedule, facade features information is relatively easy to obtain from the visual aspects of a building. By adopting several key facade attributes, a customized energy use intensity baseline model can be generated by considering building design features. Therefore, instead of using traditional and complicated simulation methods, a mathematical model can be established to estimate EUI baselines based on sufficient existing building practices data. In a national building performance survey, data such as CBECS and building energy usage are collected for a large database to provide performance guidance for new or renovation building projects. Unfortunately, averaged performance data are too aggregated and generic to identify specific conditions for each building category in a specific climate condition. In this research, a vision-based performance prediction model was developed to estimate building energy consumption based on simplified facade attribute information and weather conditions. Data about building facade features, including orientation, facade area, window-to-wall ratio, volume, surface-to-volume ratio, etc., were collected along with energy use public disclosure. A prediction model, based on this dataset, was established to estimate building energy use intensity as a function of facade features. This prediction approach will provide a more realistic EUI estimation tool for calculating an energy use baseline and will enable real-time energy usage monitoring and management of each target building.
A Review of “Modern Greece: A History since 1821”: Koliopoulos, John S., and Thanos M. Veremis, Malden, MA: Wiley-Blackwell, 280 pp., $94.95, ISBN 978-1405186810, Publication Date: December 2009

In 2002, Thanos Veremis and John Koliopoulos published their first attempt at a history of modern Greece. That book, entitled Greece: A Modern Sequel (NYU Press) offered a thematic overview of the ...
Implementation of clinical pharmacy services in a cardiac rehabilitation unit

The implementation of a comprehensive program for the rehabilitation of cardiac patients is discussed with primary emphasis on the clinical pharmacy services provided and the method of reimbursement for these clinical services. The three basic clinical pharmacy service objectives in the cardiac rehabilitation unit (CRU) are: (1) to provide drug information to the patient, his family and health-care team members; (2) to intensively monitor the drug therapy of all CRU patients, and (3) to evaluate the impact of pharmacy services being provided upon the quality of patient care and subsequent avoidable drug-related morbidity and mortality. The pharmacist is reimbursed for his clinical services from a percentage of the revenues gained from the higher room rate rather than from traditional dispensing functions and drug fees. It is concluded that the pharmacist is recognized as a necessary drug information source and an important member of the CRU team.
The synthesis of controllers for linear hybrid automata

We present a semi-decision procedure for synthesizing controllers for hybrid systems modeled as linear hybrid automata. The procedure is easily modified for partial observability, at the cost of completeness. The procedure has been implemented, and tested on the synthesis of controllers for various models of a steam boiler. Since the synthesis procedure may generate controllers that are Zeno, i.e. they prevent time from diverging, we provide sufficient, but not necessary, conditions on linear hybrid automata that guarantee that any synthesized controller is non-Zeno.
Effects of mixing on polymerizations in batch reactors: Comparison of catalytic and ionizing radiation initiations

The effects of mixing on polymerizations in batch reactors are examined theoretically for initiations by thermal decomposition of catalyst and by absorption of ionizing radiation. Mathematical expressions for predicting the first three moments of the dead polymer size distribution are presented. Two extreme mixing states, perfect and no mixing, are considered. It is shown that in batch reactors mixing in any direction in which nonuniform initiations exist increases the polymerization rate and the number average molecular weight and decreases the weight average and thus the polydispersity.
Multi-centric histiocytosis: Experimental induction in broiler and specific pathogen-free leghorn chickens.

Seventy-five 3-day-old broiler chicks and twenty specific pathogen-free leghorn chicks were injected with 0.5 ml of a homogenate, prepared from organs from broilers diagnosed with naturally-occurring multicentric histiocytosis (MH). Equal numbers of uninjected broiler and leghorn chicks (controls) were maintained in adjacent pens. Ten weeks later, nine broilers had well-developed gross and microscopic MH lesions. The distribution and histological appearance of lesions in these experimental chicks was similar to lesions described in naturally occurring field cases. Six leghorns had gross lesions similar to those found in their broiler counterparts; however, in the leghorns, the cellular masses contained more lymphocytes and, additionally, masses were found in the gizzard musculature. One gizzard contained a sarcoma. Broiler chickens with MH weighed less than their control counterparts and were more likely to be anaemic. Sequences specific for reticuloendotheliosis viruses (REV) were found in the MH homogen...
Should conventional angiography be the gold standard for carotid stenosis

PURPOSE To compare conventional angiography (CA) and rotational angiography (RA) to assess the degree of angiographically-measured stenosis versus cross-sectional area (CSA) stenosis in an in vitro carotid model. METHODS Various grades of stenosis were created by adhering different amounts of silicone rubber sealant onto the inner wall of clear, radiolucent tubes. Following 2- and 3-projection CA and 20-projection RA, the tubes were transected at the actual maximum stenosis. The cross-sectional areas were digitally photographed, and CSA stenosis was calculated using ImageJ planimeter software. The differences among CA, RA, and CSA stenosis measurements were compared statistically. RESULTS There was no significant difference between RA and CSA stenosis measurements (p=0.46). Conventional angiography with 2 or 3 projections between 0 degrees and 90 degrees underestimated the severity of disease in 19 (63%) of 30 samples. The maximum stenosis percentage was significantly lower in CA versus RA (p<0.0001 in 2-projection, p<0.0003 in 3-projection) and in CA versus CSA stenosis (p<0.0004 in 2-projection, p<0.001 in 3-projection). The maximum stenosis percentages measured by RA were less than CSA stenosis in 5 (71.4%) of 7 tubes (p=NS) containing 50% to 69% stenoses. Eight tubes had mountain-shaped lesions, which was significantly overestimated by RA (11.5%+/-9.7%, p<0.012). CONCLUSION CA with 2 or 3 projections significantly underestimates the maximum stenosis in an in vitro model. RA may overestimate disease in patients with mountain-shaped plaques and may underestimate disease if the stenosis is <70%. Our data suggest that CA should not be the gold standard for the qualification of carotid endarterectomy in asymptomatic patients, nor for vascular laboratory quality assurance analysis.
Survival and neurologic outcome of infants with medulloblastoma treated with surgery and MOPP chemotherapy. A preliminary report

The results of treatment of infants with medulloblastoma using surgery and chemotherapy, without the use of radiation therapy, are reported. Both survival and outcome, in terms of growth, neurologic deficit, and intelligence are compared with the same parameters in children treated conventionally. Although preliminary, our results suggest that chemotherapy combined with surgery is a valid option for the treatment of infants with this type of neoplasm.
A Ballet of Plant Movement

Writing for nonspecialists, Koller collects experimental findings (many from his own research) to discuss the mechanisms and adaptive value of plant movements.
Magnetic Resonance Line Shapes at the Onset of Saturation

Magnetic resonance absorption line shapes and widths in Li metal and Ca${\mathrm{F}}_{2}$ crystals have been measured as a function of radio-frequency power level. The measurements have been made on the ${\mathrm{Li}}^{7}$ resonance in Li at 77\ifmmode^\circ\else\textdegree\fi{}K and 215\ifmmode^\circ\else\textdegree\fi{}K and on the ${\mathrm{F}}^{19}$ resonance in Ca${\mathrm{F}}_{2}$ at room temperature. The measurements have been made from low rf power into the region of appreciable saturation, but not into the very high saturation region considered by Redfield. A decrease in $\ensuremath{\delta}H$, the peak-to-peak absorption derivative line width, was observed in both systems at sufficiently large values of ${H}_{1}$, the rf magnetic field. The changes of line width in Li at various values of ${T}_{1}$ and of characteristic motional frequency of the nuclei show good qualitative agreement with the criteria proposed in the recent theory of Tomita. Line-width data obtained by Redfield in aluminum are included for comparison. In the case of Ca${\mathrm{F}}_{2}$, where the spin-lattice relaxation proceeds via paramagnetic impurities, the decrease in $\ensuremath{\delta}H$ occurs at appreciably higher saturation levels than is the case in Li and Al.
Inhibition by an excitatory conductance: a paradox explained.

Ih is an excitatory inward current at subthreshold voltages, but enhancing Ih in CA1 pyramidal neurons leads to inhibition of action potential firing. A report in this issue suggests activation of the potassium current IM underlies this paradox.
Customization of the online purchase process in electronic retailing and customer satisfaction: An online field study

Abstract This paper investigates the customization of the online purchase process in electronic retailing. We conceptualize customization relevant to the two constituent sub-processes in the online purchase process: (i) decision customization—the customization of the information content delivered to customers to help them in the decision-making sub-process; and (ii) transaction customization—the customization of the purchase transaction sub-process for each customer. We draw on and synthesize the theoretical perspectives of Website Usability, Technology Acceptance Model, and Transaction Costs, to triangulate and deduce hypotheses linking customization of the online purchase process in electronic retailing and customer satisfaction. The hypotheses are tested by analyzing: (i) primary data on customization of the online purchase process collected from an online field study involving a direct observation and content analysis of the websites of 422 retailers; and (ii) secondary data on customer satisfaction with the online purchase process for the same set of 422 electronic retailers collected from a publicly available data source. The research method used for the empirical analysis is Multivariate Analyses of Covariance (MANCOVA). The results indicate that decision customization that provides choice assistance by way of personalized product recommendations is positively associated with customer satisfaction with the decision-making sub-process; and transaction customization, oriented towards making the transaction sub-process personal, convenient, and interactive is positively associated with customer satisfaction with the purchase transaction sub-process. Additionally, the results indicate that both decision customization and transaction customization are associated with overall customer satisfaction with the online purchase process of electronic retailers. The contributions, managerial implications, and limitations of the study, and directions for future research are discussed.
Interference effects on scattering by parallel fibers at normal incidence

This paper examines the radiative heat transfer through fibrous materials, focusing on the interactions between the scattered radiation from individual parallel fibers. A normally incident plane electromagnetic wave is considered, and different representative geometries are analyzed theoretically. Experimental results are presented for a specific case corresponding to fibers in one plane. The light-scattering characteristics of a single long fiber depend only on the size parameter and on the material optical constants. When multiple fibers are spaced closely together, the additional mechanism of interference between the scattered waves influences the scattering characteristics of the fiber assembly as a whole. Previous studies of radiative transport through fibrous media have ignored these effects. In this study analytical models are developed for obtaining the radiative scattering characteristics of fibrous media where the mechanism of interference is accounted for. The results indicate that interference decreases the scattering efficiency of fibrous media containing a large number of randomly positioned fibers. For other configurations the results are more complex. The predicted results are compared with experimental measurements of forward- and back-scattered light from a system of finite parallel fibers over a broad range of wavelengths. a A b B c d e
Isotropic-cholesteric phase transition in colloidal suspensions of filamentous bacteriophage fd

Abstract The co-existence concentrations of the isotropic and cholesteric liquid crystalline phases of the semi-flexible rod-like virus fd in aqueous suspension were measured as a function of ionic strength at room temperature. At several ionic strengths the magnetic-field-induced birefringence, which is proportional to the number of particles in a correlation volume N corr, was measured for fd concentrations spanning the entire isotropic region. From this data the limiting concentration of stability (spinodal) of the isotropic phase, ρ*, was obtained. The co-existence concentrations and ρ* versus ionic strength compare well with predictions based on the theory of Khokhlov and Semenov, modified to include the effects of charge. A theoretical expression for the magnetic birefringence of persistent polymers was derived and agreed well with the data with the exception that N corr at the isotropic to liquid crystal transition was smaller than predicted.
Cholesterol-lowering nature of unsaturated fat in rats may be due to its inability to increase hepatic iron.

The present investigation was conducted to determine whether the cholesterol-raising properties of saturated fat and cholesterol-lowering properties of unsaturated fat are associated with levels of hepatic iron. The magnitude of hepatic iron retention was manipulated by feeding rats diets that were either copper-deficient or -adequate, iron-adequate or -supplemented, and contained either beef tallow or corn oil. Weanling male Sprague-Dawley rats were randomly divided into eight dietary groups according to the type of dietary fat (beef tallow or corn oil) and level of dietary copper (0.74 or 6.9 μg Cu/g diet) or iron (44.4 or 86.7 μg Fe/g diet). Beef tallow and copper deficiency alone increased hepatic iron levels, which in turn were associated with increased plasma cholesterol. When the three dietary factors were combined, ie, iron, beef tallow, and copper deficiency, they induced the highest magnitude of hepatic iron retention, which in turn was associated with the highest concentration of plasma cholesterol. In contrast, when hepatic iron retention was not increased, such as by feeding a diet containing corn oil or by consumption of a copper-adequate diet, plasma cholesterol was not elevated. Based on these data, it is suggested that nutrients that have the ability to increase hepatic iron have the potential to increase plasma cholesterol.
Symbolic ideology in the American electorate

Abstract Ideological self-identification in the United States is well measured for the period 1970 to the present. Many survey measures are available and they are posed with considerable frequency and regularity. It is thus a relatively straightforward methodological exercise to combine them into a single measure of the American public's latent disposition to identify as liberal or conservative. What is problematic about this state of affairs is that the availability of these good measures occurs after a number of important changes in the American political context, changes that, we argue, have affected how Americans conceive of ideological terms and how scholars think about self-identification in the modern electorate. This paper seeks to measure and explain ideological self-identification in the time before modern survey research. We undertake an historical analysis of scattered pieces of public opinion data before 1970, assembling the pieces to build a time series of self-identification from 1937 to 2006. We then begin attempts at explaining the now observable, and often dramatic, changes in this series.
Silicon contamination of substrates in fluorocarbon plasmas produced in glass reactors

Extensive research has been carried out in recent years using fluorocarbon plasmas for modification and depositions on polymer substrates. In some cases anomalous results have been obtained that are not explainable based on conventional fluorine chemistry. In this investigation pure polypropylene films were exposed to carbon tetrafluoride plasmas in a Pyrex glass reactor. At short reaction times (less than 1 min) significant amount of silicon was detected by ESCA on the surface of the films. Analysis of liquid nitrogen trapped fluorocarbon plasma gases and molecular fragments indicated high concentrations of silicon and carbon containing species, the former indicative of ablation and etching reactions of the glass reactor walls. The production of a relatively high quantity of fluorosilicon derivatives was explained by the greater affinity of silicon for fluorine than for carbon, with the tendency to readily form SiF4. These fluorosilicon radical and ionic species generated under cold plasma conditions can easily react with polymeric substrates causing unexpected surface modifications. In addition Si–F bonds could be readily hydrolyzed to SiOH islands on the surface of the substrate to impart anomalous characteristics. © 1994 John Wiley & Sons, Inc.
RNA synthesis during bacteriophage SPO1 development: six classes of SPO1 RNA.

Abstract An analysis of RNA synthesis during development of Bacillus subtilis phage SPO1 is presented. Host transcription decreases substantially after infection. The inhibition of host transcription is non-co-ordinate, with messenger synthesis much more strongly affected than stable RNA synthesis. Viral RNA synthesis increases concurrently with this shut-down and eventually accounts for at least half of the total transcription. The program of viral transcription has been analyzed by DNA-RNA hybridization-competition. Six classes of viral transcripts can be distinguished on the basis of their times of first appearance and cessation of synthesis. Viral RNA first appears about one minute after formation of phage-bacterial complexes, e and em viral RNA start to be synthesized at that time and e RNA synthesis lasts only until about the fourth minute, while em RNA synthesis is shut-off soon after the start of viral DNA replication, m and m1l, RNA synthesis starts four to five minutes after infection; m transcription ceases soon after the onset of DNA replication whereas m1l, transcription continues throughout the rest of the viral eclipse period. m2l and l transcripts first appear a little before, and several minutes after, the start of replication, respectively; m2l and l RNA continue to be made throughout the rest of the viral eclipse period.
Carbon-assisted lateral self-assembly of amorphous silica nanowires

Amorphous silica nanowires generally grow in either a metal-catalyzed vapour–liquid–solid (VLS) process or a solid–liquid–solid (SLS) process. So far, ordered alignment of impurity-free SiOx (1 < x < 2) nanowires has not been achieved. In this study, without using metal catalysts, laterally aligned amorphous silica nanowire arrays have been successfully synthesized on a Si(100) substrate surface at ∼700–1100 °C. These amorphous silica nanowires have diameters of ∼100–350 nm and lengths of ∼1–20 μm, which are uniformly decorated with ∼4–11 nm SiO nanocrystals as a result of possible thermal decomposition of amorphous silica at high temperature. A carbon-assisted and lattice strain driven mechanism might be responsible for the lateral alignment of these SiO nanocrystal decorated amorphous silica nanowires.
Domain of stability for a class of non-linear partial differential equations†

The domain of stability in the weak topology of a parabolic partial differential equation with negative feedbacks in two independent variables is determined explicitly in terms of the Weierstrass p-function. Locations of singularities are found for the equianharmonic case.
Photoelectric control of equi-illumination lighting systems

Abstract The ability of a photoelectrically controlled lighting system to maintain a constant light level on a task surface by responding to changing daylight levels is affected by the control algorithm used to relate the photosensor signal to electric light levels and by the geometry and location of the photosensor. We describe the major components of a typical equi-illumination system, discuss the design and operation of such a system, and examine the effects of the control algorithm and photosensor shielding. Equations for the control photosensor signal are developed that separate the signal into electric light and daylight components. We then present mathematical descriptions for the constant set-point control algorithm used by most manufacturers. An alternative, sliding set-point algorithm is proposed in which the total photosensor signal is a linear function of the signal's daylight component. Computer simulations of the performance of dimmable lighting control systems driven by ceiling-mounted photosensors were run for a test room under various daylight conditions. Control systems using the constant set-point algorithm were unable to provide the target light level continuously, although shielding the ceiling-mounted photosensor from the window luminance resulted in higher maintained levels with less variability than did using unshielded photosensors. The use of a sliding set-point algorithm in lieu of a constant set-point algorithm improved the performance of systems driven by both shielded and unshielded photosensors. When a sliding set-point system was used in conjunction with a photosensor shielded from the window, a nearly constant light level was maintained at the task surface regardless of daylight condition.
Impact of end-user decisions on pricing in wireless networks

We consider the impact of end-user decision-making on pricing of wireless resources when there is uncertainty in the Quality of Service (QoS) guarantees offered by the Service Provider (SP). Specifically, we consider a scenario where an SP tries to sell wireless broadband services to a potential customer when the advertised transmission rate cannot be fully guaranteed at all times. Relying on Prospect Theory (PT), a Nobel Prize winning theory developed by Kahneman and Tversky to explain people's real life decision-making that often violates the principles of the Expected Utility Theory (EUT), we formulate a game theoretic model to study the interplay between price offerings of the SP and the service choices made by the end-user. We characterize the Nash Equilibrium (NE) of the underlying game and provide insights into the impact of the deviations of decision-making from that expected under EUT and show how pricing can be used as a mechanism to mitigate such impact.
Proton magnetic resonance imaging using a nitrogen–vacancy spin sensor

Two-dimensional magnetic resonance imaging of hydrogen in organic samples with a resolution of 12 nm can be achieved by using the spin of a nitrogen–vacancy centre in diamond as a sensor. Magnetic resonance imaging, with its ability to provide three-dimensional, elementally selective imaging without radiation damage, has had a revolutionary impact in many fields, especially medicine and the neurosciences. Although challenging, its extension to the nanometre scale could provide a powerful new tool for the nanosciences, especially if it can provide a means for non-destructively visualizing the full three-dimensional morphology of complex nanostructures, including biomolecules1. To achieve this potential, innovative new detection strategies are required to overcome the severe sensitivity limitations of conventional inductive detection techniques2. One successful example is magnetic resonance force microscopy3,4, which has demonstrated three-dimensional imaging of proton NMR with resolution on the order of 10 nm, but with the requirement of operating at cryogenic temperatures5,6. Nitrogen–vacancy (NV) centres in diamond offer an alternative detection strategy for nanoscale magnetic resonance imaging that is operable at room temperature7. Here, we demonstrate two-dimensional imaging of 1H NMR from a polymer test sample using a single NV centre in diamond as the sensor. The NV centre detects the oscillating magnetic field from precessing protons as the sample is scanned past the NV centre. A spatial resolution of ∼12 nm is shown, limited primarily by the scan resolution.
Pion-nucleus scattering

An energy-dependent analysis of elastic scattering of {pi}{sup +} from {sup 12}C, {sup 16}O, and {sup 40}Ca is made based on differential cross sections and (in one case) reaction cross sections. A nonlocal optical model is used to provide the energy variation between data sets. Structure is found in the s- and p-wave phase shifts. {copyright} {ital 1998} {ital The American Physical Society}
MK-801 blocks the expression but not the development of tolerance to morphine in the isolated spinal cord of the neonatal rat

Abstract This study investigated the role of (MK-801; [(+)-5-methyl-10,11-dihydro-5H-dibenzo[a, d]-cyclo-hepten-5,10-imine hydrogen maleate) in the development and expression of tolerance to morphine in the isolated spinal cord of the neonatal rat. Neonatal rats were treated chronically (3 or 4 days) with either morphine, morphine + MK-801, MK-801 alone or saline. Morphine, in a concentration-dependent manner, depressed a delayed ventral root potential produced by supramaximal electrical stimulation of an ipsilateral dorsal root. Chronic treatment of neonates with morphine alone, morphine with MK-801 and MK-801 alone produced tolerance to morphine depression of the ventral root potential. Acute MK-801 (300 nM) did not depress the ventral root potential but enhanced the depressant effects of acute morphine on the ventral root potential in saline-treated controls. Acute MK-801 (300 nM) appeared to reverse tolerance in all of the drug-treated groups. We conclulate that MK-801 can mask the expression of morphine tolerance by enhancing the acute depressant effects of morphine.