cssi/SciSciGPT-SciSciNet huggingface dataset:
A new approach to clustering soil profile data using the modified distance matrix

Abstract The application of different data mining methods for large soil profile datasets can be very useful for many agricultural and natural resource management applications, ranging from crop modeling to soil taxonomy. Distance or dissimilarity measures are key features of these methods. The proximity measure or the distance between vectors is calculated when they have the same dimensions. In the case of the soil profile data, the corresponding matrices representing different soils and their horizon properties usually have different dimensions. The objectives of this study were to explore a new approach for creating a semi-metric based on adjustment of the soil profile horizons, implement it in the computer application and to apply the modified distance matrix calculation to maximize the use of soil horizon properties for soil data mining. We assume that each soil horizon is homogenous while a vertical heterogeneity of soil profile is expressed through different soil horizons. Therefore, any sublayers of a horizon are characterized with the same values for its attributes as the horizon itself. In our approach, we developed matrices with the same dimension for soil profiles and calculated the proximity measure. The algorithm was implemented as an easy to use Fortran application that can calculate the modified distance matrix (MDM) for low- and high-dimensional soil profiles data. The proposed approach was shown to be effective when using existing reliable datasets, such as WISE Version 3.1, a global soil profile database developed by ISRIC. Hierarchical clustering was performed using the MDM based on the original algorithm of soil profile horizons adjustment with further integration into R. The principal finding shows that a proposed modified distance matrix can be used with different clustering methods for soil profile data clustering on a horizon-by-horizon basis. This study established a new methodology for using the modified distance matrix calculation and applying it with different clustering algorithms to large sets of soil profile data obtained from detailed soil surveys.
Factors Affecting Patientsâ€™ Perceptions of Quality, Hospital Ratings, and some Thoughts about Post-COVID-19 Challenges

Objective: To highlight clinical and operational issues, identify factors that shape patient responses in Hospital Consumer Assessment of Healthcare Providers a
Men’s Purchase Behavior and Fit Preferences for Compression Sportswear for Fitness

The overall sales growth of men’s sportswear surpassed women’s in the U.S. by 2% in 2019. With this trend, the purpose of this study was to identify preferred sportswear brands; relationships among body types; exercising routines and sportswear sizes were examined to provide basic information for designing effective men’s compression sportswear. The targeted population was men aged 18-35. The data of total 120 respondents were used for statistical analyses by using 11 close- and open- ended questions. The results indicated that the primary body locations (i.e., chest, shoulder, abdomen, waist, back, and knee) were found to be important for providing intensive compression for fitness. The three sportswear brands, Nike, Adidas, and Under Armour, were preferred by the majority of participants. No significant differences among BMI ranges based on the vertical fit evaluations were found. Therefore, future studies should concentrate on horizontal body dimensions in correlation to the BMI ranges.
Clinical Course and Features of Seizures Associated With LGI1-Antibody Encephalitis.

Background and Objectives To determine risk factors associated with clinical relapses and development of chronic epilepsy in patients with anti–leucine-rich glioma-inactivated 1 (LGI1) immunoglobulin G encephalitis. Methods Patients with seizures related to LGI1-antibody encephalitis with ≥24 months of follow-up from disease onset were identified in the Mayo Clinic electronic medical record and neuroimmunology laboratory records. Charts were reviewed to determine clinical factors, seizure types, imaging, treatment, occurrence of relapse, and outcome. Binary logistic regression analysis was performed to identify predictors of the development of chronic epilepsy. Univariate Cox proportional hazards regression was used to examine the influence of baseline characteristics on relapse risk. Results Forty-nine patients with LGI1-antibody encephalitis and acute symptomatic seizures were identified. Almost all patients (n = 48, 98%) were treated with immunotherapy. Eight had definite and 2 had possible chronic epilepsy at the last follow-up (10 of 49, 20.4%). Female sex (p = 0.048) and younger age at disease onset (p = 0.02) were associated with development of chronic epilepsy. Relapses occurred in 20 (40.8%), with a median time to first relapse of 7.5 months (range 3–94 months). Initial treatment with long-term steroid-sparing immunotherapy was associated with reduced risk of relapse (hazard ratio 0.28, 95% confidence interval 0.11–0.73, p = 0.009). Discussion Chronic epilepsy occurred in 20.4% of our patients with LGI1-antibody encephalitis despite aggressive immunotherapy. Risk factors for chronic epilepsy were female sex and earlier age at onset. Relapses occurred in 40.8% of patients with prolonged follow-up, and long-term steroid-sparing immunotherapy was associated with a lower relapse rate.
The Impact of Retinitis Pigmentosa on Young Adults: Psychological, Educational, Vocational and Social Considerations:

Retinitis pigmentosa (RP) refers to a group of inherited retinal degenerative disorders in which night and peripheral vision are gradually lost. A national sample of young adults with RP reveals th...
Longitudinal Trajectories of Hair Cortisol: Hypothalamic-Pituitary-Adrenal Axis Dysfunction in Early Childhood

The objective of this study was to examine if longitudinal trajectories of hair cortisol concentrations (HCC) measured at two or three yearly time points can identify 1-3 year old children at risk for altered hypothalamic-pituitary-adrenal (HPA)-axis function due to early life stress (ELS). HCC was measured (N = 575) in 265 children using a validated enzyme-linked immunosorbent assay. Hair was sampled in Clinic Visits (CV) centered at years 1, 2, and 3 (n = 45); 1 and 2 (n = 98); 1 and 3 (n = 27); 2 and 3 (n = 95). Log-transformed HCC values were partitioned using latent class mixed models (LCMM) to minimize the Bayesian Information Criterion. Multivariable linear mixed effects models for ln-HCC as a function of fixed effects for age in months and random effects for participants (to account for repeated measures) were generated to identify the factors associated with class membership. Children in Class 1 (n = 69; 9% Black) evidenced declining ln-HCC across early childhood, whereas Class 2 members (n = 196; 43% Black) showed mixed trajectories. LCMM with only Class 2 members revealed Class 2A (n = 17, 82% Black) with sustained high ln-HCC and Class 2B (n = 179, 40% Blacks) with mixed ln-HCC profiles. Another LCMM limited to only Class 2B members revealed Class 2B1 (n = 65, 57% Black) with declining ln-HCC values (at higher ranges than Class 1), and Class 2B2 (n = 113, 30% Black) with sustained high ln-HCC values. Class 1 may represent hair cortisol trajectories associated with adaptive HPA-axis profiles, whereas 2A, 2B1, and 2B2 may represent allostatic load with dysregulated profiles of HPA-axis function in response to varying exposures to ELS. Sequential longitudinal hair cortisol measurements revealed the allostatic load associated with ELS and the potential for developing maladaptive or dysregulated HPA-axis function in early childhood.
An Emerging Scholar’s Guide to Writing Theory-Based Post-Positivistic Academic Articles

It is important to realize that in writing an academic research article, there is an expected structure that virtually all research articles follow. This structure becomes even more pronounced for certain disciplines and journals. Thus, the first rule of thumb is that when you are planning a research project or drafting a paper that you find a couple of exemplar articles that use similar methods and/or theories as you use, from top journals in the field that you want to have the conversation in. Follow these articles in terms of structure, style, quality of evidence, degree of detail, and so on. That being said, an academic article will generally have the following structure, from which you should almost never depart: 1. Abstract 2. Introduction / motivation 3. Background / literature review 4. Theory and hypothesis development 5. Method and procedures 6. Analysis and results 7. Discussion 8. Conclusion 9. References 10. Support appendices In the following working paper, I describe these sections, and provide recommendations on how to best structure them for improved motivation and argumentation. My focus is on empirical articles that are theory-based and have a post-positivistic epistemology, although many of my recommendations apply to other types of articles.
Vitamin D: Genetics and Genomic Effects

Vitamin D is normally thought of as an environmental factor. However, even when all the factors known to influence vitamin D concentrations, as measured by 25-OH vitamin D (25(OH)D), are taken into account, there is substantial interindividual variability in vitamin D levels. While it is possible that other, undefined, environmental factors contribute to the large interindividual variability noted with 25(OH)D levels, perhaps a more likely explanation for these differences lies in genetics. Indeed, recent studies have demonstrated that 25(OH)D levels are heritable and strongly influenced by variants in key vitamin D regulatory genes. In this chapter, we will review the evidence that supports circulating vitamin D levels as being heritable, discuss the candidate gene studies demonstrating an association of vitamin D pathway genes with 25(OH)D levels, detail the genome-wide association studies (GWAS) performed to date, and relate the significance of data generated via ChIP-Seq methods to interindividual variation in response to vitamin D. Following this overview of the genetic determinants of vitamin D level/activity, we will review the salient studies relating genetic variation within the vitamin D pathway to specific respiratory disease outcomes. While these latter studies are in their relative infancy, they reflect the potential for vitamin D, in combination with genetic variation, to influence pulmonary disease susceptibility and therapy.
Sphingosine-1-phosphate inhibits IL-1–induced expression of C-C motif ligand 5 via c-Fos–dependent suppression of IFN-β amplification loop

The neuroinflammation associated with multiple sclerosis involves activation of astrocytes that secrete and respond to inflammatory mediators such as IL-1. IL-1 stimulates expression of many chemokines, including C-C motif ligand (CCL) 5, that recruit immune cells, but it also stimulates sphingosine kinase-1, an enzyme that generates sphingosine-1-phosphate (S1P), a bioactive lipid mediator essential for inflammation. We found that whereas S1P promotes IL-1-induced expression of IL-6, it inhibits IL-1-induced CCL5 expression in astrocytes. This inhibition is mediated by the S1P receptor (S1PR)-2 via an inhibitory G-dependent mechanism. Consistent with this surprising finding, infiltration of macrophages into sites of inflammation increased significantly in S1PR2(-/-) animals. However, activation of NF-κB, IFN regulatory factor-1, and MAPKs, all of which regulate CCL5 expression in response to IL-1, was not diminished by the S1P in astrocytes. Instead, S1PR2 stimulated inositol 1,4,5-trisphosphate-dependent Ca(++) release and Elk-1 phosphorylation and enhanced c-Fos expression. In our study, IL-1 induced the IFNβ production that supports CCL5 expression. An intriguing finding was that S1P induced c-Fos-inhibited CCL5 directly and also indirectly through inhibition of the IFN-β amplification loop. We propose that in addition to S1PR1, which promotes inflammation, S1PR2 mediates opposing inhibitory functions that limit CCL5 expression and diminish the recruitment of immune cells.
Expression of Platelet-derived Growth Factor B-Chain and the Platelet-derived Growth Factor Receptor β Subunit in Human Breast Tissue and Breast Carcinoma

Abstract Breast carcinomas are known to express platelet-derived growth factor (PDGF), a known connective tissue mitogen. In order to further evaluate the potential role of PDGF in these epithelial tumors, expression of the PDGF B chain (PDGF-B) and the PDGF receptor β subunit (PDGFR) was analyzed by immunocytochemistry and in situ hybridization in 49 benign and malignant breast tissues. PDGF-B expression was analyzed with respect to the expression of the proliferating cell nuclear antigen, as well as tumor grade, p53 overexpression, estrogen receptor, progesterone receptor, and c- erb B-2 expression. Expression of PDGF-B protein and mRNA was restricted to the breast epithelium and tumor cells except for scattered tissue macrophages. A strong correlation was found between increasing proliferating cell nuclear antigen indices and PDGF-B expression in both nonmalignant ( P = 0.01) and malignant ( P = 0.02) breast specimens. Decreased PDGF-B expression was found in postmenopausal atrophic breast tissue compared with normal breast tissue ( P = 0.04). Within the subgroup of malignant tumors, no correlations were found between PDGF-B expression and tumor grade or p53 overexpression. In 16 of the malignant tumors evaluated for estrogen/progesterone receptor status and c- erb B-2 overexpression, no correlations with PDGF-B expression were found. Membranous PDGFR immunostaining was present within the fibroblastic cell population in all of the tissues examined but not in the nonmalignant breast epithelium. Six malignant specimens had detectable cytoplasmic expression of PDGFR. There was no correlation between this PDGFR expression and proliferating cell nuclear antigen indices, but a correlation was noted between increasing estrogen receptor expression and PDGFR cytoplasmic expression ( P = 0.04). The results support a paracrine role for PDGF-B in malignant and benign breast epithelial cell proliferation.
Occupational physicians and environmental medicine

Physicians who practice environmental medicine seek to identify and to prevent patient and population exposures that cause adverse human health outcomes. Epidemiologic, toxicologic, clinical, and public health skills essential to this enterprise are indistinguishable from those of the occupational physician. Several important controversies illustrate the essential role of occupational physicians in environmental health science and policy, including environmental asbestos, dioxin, electromagnetic fields, and carcinogenicity testing. Our continuing involvement in environmental issues is predicted by three conditions, each unlikely to change. The human remains the animal of greatest interest; the natural experiment will have been performed (however unwittingly); and the work site will continue to provide that first and clearest setting for measuring the outcome. Therefore, residency training must be expanded so that future occupational and environmental physicians will recognize their fundamental role in environmental health. The results of our industry cross factory walls with ease. So must our efforts.
The Deployment and Maintenance of a Condor-Based Campus Grid

Many institutions have all the tools needed to create a local grid that aggregates commodity compute resources into an accessible grid service, while simultaneously maintaining user satisfaction and system security. In this paper, we present the strategy used at Clemson University to deploy and maintain a grid infrastructure by making resources available to both local and federated remote users for scientific research. Virtually no compute cycles are wasted. Usage trends and power consumption statistics collected from the Clemson campus grid are used as a reference for best-practices. After several years of cyber-evolution, the loosely-coupled components that comprise the campus grid work together to form a highly cohesive infrastructure that not only meets the computing needs of local users, but also helps to fill the needs of the scientific community at large. Experience gained from the deployment and management of this system may be adapted to other grid sites, allowing for the development of campus-wide, grid-connected cyberinfrastructures.
Disgust and Its Disorders: Theory, Assessment, and Treatment Implications

Disgust and Its Disorders: Theory, Assessment, and Treatment Implications thoughtfully examines the role of disgust in psychopathology by highlighting important theoretical and methodological developments and discussing recent research on behavioral patterns that can be provoked by disgust. Contributors demonstrate that disgust plays an important role in a wide range of psychopathology, including sexual dysfunction, eating disorders, animal phobias, and obsessive - compulsive disorder. Disgust is shown to be a multidimensional construct that centers on the unifying theme of potential contamination of the body, soul, and broad social order. Editors Bunmi O. Olatunji and Dean McKay thoroughly review the available research on disgust and shed light on how its interpretation will in turn facilitate the development of better treatment.
African American hypertensive nephropathy maps to a new locus on chromosome 9q31-q32

Hypertensive nephropathy (HN) and focal segmental glomerulosclerosis (FSGS) are significant causes of end-stage renal disease (ESRD), but no genes or loci have been associated with this phenotype among African Americans, a group at high risk. We performed a genomewide linkage scan with ∼400 microsatellite markers on 23 individuals of a large four-generation African American family with 18 affected individuals (7 with ESRD), in which the 13-year-old proband (also with ESRD) presented with hypertension and proteinuria (2–4 g/day) and underwent a kidney biopsy that revealed FSGS-like lesions with arteriolar thickening. A genomewide scan revealed LOD scores of >2.5 for markers on chromosomes 3 and 9, and fine mapping was performed on 5 additional members (total 28 members) that showed a maximum multipoint LOD score of 5.4 in the 9q31-q32 region, under an autosomal dominant model with 99% penetrance. This 8-cM (6-Mb) region is flanked by markers D9S172 and D9S105, and further candidate gene sequencing studies excluded the coding regions of three genes (ACTL7A, ACTL7B, and CTNNAL1). To our knowledge, this is the first report of a locus, denoted as “HNP1,” for the HN/FSGS phenotype in a large African American family with dominantly inherited nephropathy characterized by ESRD, hypertension, and some features of FSGS.
All pairs suffice for a P-set

Abstract A P-set of a symmetric matrix A is a set α of indices such that the nullity of the matrix obtained from A by removing rows and columns indexed by α is | α | more than the nullity of A. It is known that each subset of a P-set is a P-set. It is also known that a set of indices such that each singleton subset is a P-set need not be a P-set. This note shows that if all pairs of vertices of a set with at least two elements are P-sets, then the set is a P-set.
The resistance and magnetoresistance of lithium tetra-ammine

Resistance and magnetoresistance measurements are presented for specimens of Li(NH3)4 with mole ratios of 4:1, NH3:Li. Measurements were made using a probeless, mutual inductance technique from 1.5 to 4.2 K and from 10 to 100 K. The low-temperature resistivity has a largely quadratic temperature dependence, ρ=ρ(0)+BT2. The coefficient B has only a small temperature variation from 1.5 to 25 K and is independent of the residual resistivity. Near 69 K there is a local minimum in the electrical resistivity. Thermal hysteresis is observed in this region as well. We suggest that these features are characteristic of the compound Li (NH3)4 and may be due to a magnetic transition near 70 K. The magnetoresistivity was determined from 0 to 100 kG at both 1.66 and 4.2 K. It is large, with a marked decrease in field dependence above 50 kG. Our results indicate that lithium tetra-ammine is probably an uncompensated metal with a high proportion of open-orbit carriers.
ACUTE COMPLICATIONS OF STEM CELL TRANSPLANT

Objectives To provide a comprehensive review of the acute complications that occur during the first 100 days post stem cell transplant (SCT). Data Sources Research studies, book chapters, websites, and articles. Conclusion Even though the outcomes for SCT continue to improve, the complications seen in the first 100 days post transplant are a significant cause of mortality. Astute nursing assessment with resultant early intervention improves treatment-related mortality. Implications for Nursing Practice Because SCT patients are seen in every oncology care setting, knowledge of these acute complications is essential to helping the nurse care for and educate SCT recipients.
Accomplishments and Challenges Mark Former NOAA Administrator Lubchenco's Tenure

Progress and challenges in several key areas—including weather satellites, the federal budget, climate change, ocean policy, and fisheries—are among the issues that Jane Lubchenco faced as administrator of the U.S. National Oceanic and Atmospheric Administration (NOAA) and under secretary for oceans and atmosphere of the U.S. Department of Commerce (of which NOAA is a part) from 2009 until her departure on 27 February 2013. Lubchenco is returning to the West Coast, where this spring she will be a visiting scholar at Stanford University's Haas Center for Public Service. With her departure, Kathryn Sullivan, the assistant secretary of commerce for environmental observation and prediction and NOAA deputy administrator, became the agency's acting administrator.
Vibrational frequencies and structural determination of digermyl sulfide

Abstract The normal mode frequencies and corresponding vibrational assignments of digermyl sulfide in C 2 v symmetry are examined theoretically using the Gaussian 98 set of quantum chemistry codes. All normal modes were successfully assigned to one of six types of motion (Ge–H stretch, Ge–S stretch, Ge–S–Ge bend, H–Ge–H bend, GeH 3 wag, and GeH 3 twist) predicted by a group theoretical analysis. Comparing the vibrational frequencies with IR and Raman spectra available in the literature, scaling factors are derived. Predicted infrared and Raman intensities are reported.
Ghost Fluid Method for Strong Shock Interactions Part 1: Fluid-Fluid Interfaces

The interaction of shocks with multimaterial interfaces can occur in several applications, including high-speed flows with droplets, bubbles, and particles and hypervelocity impact and penetration. To simulate such complicated interfacial dynamics problems, a fixed Cartesian grid approach in conjunction with level-set interface tracking is attractive. In this regard, the ghost fluid method has been widely used to capture the interface dynamics. However, ghost fluid method experiences difficulties, particularly when strong shocks impinge on the interface. It has been shown that an accurate representation and decomposition of the wave systems (by solving a Riemann problem at the interface) significantly alleviates the shortcomings confronted by the ghost fluid method. Variants of the ghost fluid method proposed in the past differed in the way in which this Riemann problem was invoked at the interface. In this work, a simple, robust, and multidimensional procedure to construct the Riemann problem at the interface is presented. The work focuses primarily on resolving interface dynamics due to strong shocks interacting with embedded fluid-fluid interfaces (gas-gas and gas-liquid interfaces) in compressible flows. Several one- and two-dimensional problems involving moderate-to-very-large deformation of the embedded interface have been computed. The numerical examples demonstrate the flexibility, stability, and versatility of the approach in successfully resolving the embedded material interface.
Conductive Hearing Loss Results in a Decrease in Central Auditory System Activity in the Young Gerbil

Objectives/Hypothesis: The impact of childhood conductive HL (CHL) on development of auditory function has long been debated. The present study was conducted to define and compare the consequences of CHL and cochlear ablation (CA) in young and adult animals, using 2-deoxyglucose (2-DG) uptake as a measure of metabolic activity. It was hypothesized that, for both ages, CHL would result in a decrease in activity in the major ascending central auditory system pathway of the manipulated ear, but that this decrease would be significantly less than that observed with CA. Study Design: Shamcontrolled study of metabolic effects of CHL during sound stimulation. Methods: Gerbils (aged 21 days or adult), underwent malleus removal, CA, or a sham procedure. Young animals survived either 48 hours or 3 weeks; adults survived 3 weeks. Each age/survival CHL group contained eight animals; otherwise, each group (CA and sham) contained five animals, for a total number of 54. At the appropriate survival time, animals were given an intracardiac injection of 14 C-2-DG, and sacrificed under anesthesia after 45 minutes of exposure to normal laboratory sounds. Tissue sections were prepared for exposure to x-ray film for optical density measurements, and alternate sections stained for identification of nuclei. Measurements from auditory nuclei of experimental animals were corrected against an unaffected control area (abducens nucleus) and compared with measurements taken from animals in the sham group. Auditory evoked potential thresholds to both air- and bone-conducted stimuli were obtained in a second group of neonatal and adult animals. Results: Both CHL and CA resulted in a marked decrease in 2-DG uptake in the major ascending projection of the manipulated ear, in both the neonatal and adult animals. In young animals, effects of CHL and CA were similar. Effects of CHL in adult animals were less marked and significantly different from either effects of CHL in young animals or effects of CA in adult animals. HL following malleus removal only was purely conductive and ranged from 38 to 55 dB across frequency. Conclusions : Results suggest that, particularly in young animals, a unilateral CHL may have profound effects on metabolic activity in the central auditory system.
Psychological Issues in End-of-Life Care

This paper provides a systematic, evidence-based review of the psychological issues confronted by patients at the end of life, drawing on recent literature. The epidemiology, approach to clinical assessment, clinical presentation, and therapeutic options related to common psychological issues that arise in end-stage illness are described. The spectrum of normal and dysfunctional reactions are identified, and approaches to enhancing coping and quality of life are emphasized. The learner will be able to describe: (1) normal coping responses of patients at the end of life; (2) epidemiology of common psychiatric disorders at the end of life; (3) the approach to clinical assessment of psychological distress at the end of life; and (4) therapeutic approaches to common psychological problems at the end of life.
Multiplex Ligation-Dependent Probe Amplification Identification of Whole Exon and Single Nucleotide Deletions in the CFTR Gene of Hispanic Individuals with Cystic Fibrosis

A disparity between Caucasian and Hispanic mutation detection for cystic fibrosis continues to exist, although the carrier frequency is only moderately lower in Hispanics. We aimed to identify exonic rearrangements that remained undetected by conventional methods. In seven of 32 cystic fibrosis-affected self-identified Hispanics for whom only one or no mutations were identified by extensive molecular testing, exon deletions appeared to be present with a multiplex ligation-dependent probe amplification (MLPA) assay. Two recurrent deletions (of exons 2–3 and exons 22–23) were identified in one and three patients, respectively (12.5%, 11.1% of unidentified alleles). Two apparently novel deletions (exons 6b and 20) were identified in three additional patients. Subsequent sequencing to characterize deletion breakpoints, however, identified single nucleotide deletions at the probe binding sites close to the ligation point. All resulted in false positive MLPA deletion signals. Interestingly, these mutations were not common in Caucasians, and one (935delA) was common in U.S. Hispanics. On examination of all probe binding sites, we identified a total of 76 reported mutations and five silent variants that immediately surrounded the MLPA ligation sites, with 22 occurring in non-Caucasians. These mutations are not all rare. Thus, apparent exon deletions by MLPA may indicate the presence of both large deletions and point mutations, with important implications for pan-ethnic MLPA testing in cystic fibrosis and other genetic conditions.
Technique to improve the effective fill factor of digital mammographic imagers

Current clinical mammographic imaging has been limited to screen/film, but advances in photodetector and x-ray converter technology has opened up the possibility of significantly improving mammographic screening with digital imagers. One limitation of some recently developed in direct detection imagers is a limited optical fill factor in the photodetector. A small fill factor reduces the amount of light collected from individual x-ray interactions in the screen. It can also lead to an overall reduction in the number of x-ray quanta detected. In addition, the fill factor usually decreases with an increase in photodetector resolution. To reduce these effects, we propose a technique for improving the effective fill factor of any indirect detection imager by incorporating focusing microlens arrays between the phosphor screen and the photodetector. In this investigation, we evaluate the light collection efficiencies of our proposed imager/microlens combination using Monte Carlo simulation and optical ray tracing.
Alteration of immunoregulatory mechanisms during cytomegalovirus mononucleosis: Effect of in vitro culture on lymphocyte blastogenesis to viral antigens

Abstract Immunoregulation of lymphocyte blastogenesis was studied in 13 patients with acutephase cytomegalovirus (CMV) mononucleosis and 9 of these patients during the convalescent phase of the illness. Peripheral blood mononuclear leukocytes from acutephase patients displayed depressed uptake of [3H-]thymidine in response to the lectinmitogen concanavalin A (Con A) and immune-specific viral antigens (CMV, herpes simplex virus (HSV), mumps virus) compared with convalescent patients or normal donors. Removal of plastic-adherent cells from the patients' samples resulted in further depression of lymphocyte blastogenesis to Con A and CMV and HSV antigens, suggesting a helper function for the predominantly monocytic, adherent cell population in this response. Preliminary culture of mononuclear leukocytes from acute-phase patients for 18 hr at 37°C resulted in significantly enhanced blastogenesis to Con A. In sharp contrast, lymphocyte blastogenesis to viral antigens was not significantly enhanced after preculture. These results suggest that different mechanisms are operative in immunoregulation of lymphocyte recognition responses to the polyclonal activator Con A and immune-specific viral antigens during human CMV infection.
Gap junctions synchronize the firing of inhibitory interneurons in guinea pig hippocampus.

Abstract The convulsant 4-aminopyridine (4AP) facilitates the synchronous firing of interneurons in the hippocampus, eliciting giant inhibitory postsynaptic potentials (IPSPs) in CA3 pyramidal cells. We used the gap junction blocker carbenoxolone to investigate the role of electrotonic coupling in both the initiation and the maintenance of 4AP-facilitated inhibitory circuit oscillations. Carbenoxolone abolished all synchronized IPSPs in CA3 cells elicited by 4AP in the presence of ionotropic glutamate receptor blockers. Carbenoxolone also blocked the isolated synchronized GABA B IPSPs generated in CA3 cells by a subpopulation of interneurons. These data confirm that: (1) the interneurons producing GABA B responses in CA3 cells are electrotonically coupled, and (2) gap junctions among interneurons are essential for initiating synchronized interneuron oscillatory firing in 4AP.
Immunosuppression in cardiac transplantation: science, common sense and the heart of the matter.

George Santayana, philosopher (1863–1952)Until recently, immunosuppressive management in hearttransplantation has principally been guided by observa-tional trials as opposed to more rigorous prospective, ran-domized and placebo-controlled, trials. During the pastdecade, a demand for more scientiﬁcally sound trial designhas emerged in tandem with the availability of newer im-munosuppressant drugs. This contemporary era was ush-ered in by the completion of the ﬁrst placebo-controlledtrial comparing mycophenolate mofetil with azathioprinein cyclosporine-treated patients (1). This trial taught us animportant lesson, that despite the intention to undertakethe most rigorous trial design one must be attentive to thecomplexityofthepopulationunderstudy.Inthecaseoftheaforementioned trial, the primary end point was not metas adjudicated by a prespeciﬁed intent to treat analysis.This was in large part due to randomization of patients
Rapid assessment of cardiac output and central blood volumes from indicator dilution curves without precalculation using programmable calculators.

Abstract The program described here provides complete analysis of the indicator dilution curve by incorporating densitometric calibration and logarithmic downslope fit for the widely used Hewlett-Packard 67/97 hand calculator series. Densitometric sensitivity is calculated from the linear regression as the dye calibration factor; thus, direct entry of the dye curve deflections eliminate the necessity to precalculate curve concentration. The program displays appropriate sequential time intervals prompting deflection entry of the upslope and initial exponential downslope of the curve. The remainder of the curve is generated from the logarithmically extrapolated initial downslope, and the area of the curve is then obtained for calculation of cardiac output, mean transit time, and central blood volume. Programming versatility and the rapid (4–5 min) immediate analysis of indicator dilution curves are thus available.
Developing Technologies and Radiology Health Services Research

Radiology technology changes fast, with new innovations the rule rather than the exception. This rapid technological progression makes performance of radiology health services research a particular challenge. Should research be focused early on the newly developing techniques, or should be such efforts be limited to those technologies that have reached a relatively mature and stable state? There are advantages and disadvantages to both approaches. Mature technologies may be stable for a long enough period to allow in-depth investigation. However, the rate of diffusion of imaging technology tends to match the rate of development. By the time technologies are mature, they may be so completely integrated into practice that the results of even well-designed research may have limited ability to change practice. Alternately, radiology health services researchers can focus their attention on developing technologies. These may still be in evolution, but yet have incomplete penetration, and therefore greater ease of potential practice change. Of course, there is the risk that a developing technology will change by the time research evaluating its role is complete. In this Radiology Alliance for Health Services Research (RAHSR) issue of Academic Radiology, we provide a set of related articles on the progress, challenges, and current state of research on the effectiveness of vertebral augmentation for osteoporotic compression fractures. Melton and Kallmes (1) introduce the epidemiology of vertebral fractures, Kallmes (2) discusses the state of current research efforts, and Hollingworth and Jarvik (3) de-
Institutional Constraints on Social Movement “Frame Extension”: Shifts in the Legislative Agenda of the American Federation of Labor, 1881–1955

"Frame extension" is an important frame-alignment strategy for increasing social movement membership. Little research has addressed how the institutional environment of a social movement organization constrains and compels the organization to extend its frame among potential adherents. Elaborating on the bargaining perspective and the concept of multiorganizational field, we develop market and political models of the impact of social movement dependence relations with movement antagonists and political opportunity on frame extension. Our examination of these models with a multivariate time-series regression analysis of changes in the legislative agenda of the American Federation of Labor (AFL) over its complete history suggests that the AFL extended its frame among potential adherents in response to declining employer dependence on unions for labor-supply and increasingpolitical opportunity. We conclude with implications of thefindings for future research on contemporary union decline and institutional and environmental influences on social movement frame-alignment processes.
Whitman as the Nazarene: An Unpublished Drawing

Presents a letter from Edward Carpenter to an unidentified "Benjamin," describing Carpenter's first meeting with Whitman on May 2, 1877; Carpenter's sketch of Whitman's face, which accompanies the letter, appears on the back cover of the issue.
Application of Parallel Hybrid Algorithm in Massively Parallel GPGPU—The Improved Effective and Efficient Method for Calculating Coulombic Interactions in Simulations of Many Ions with SIMION

In our previous study, we introduced a new hybrid approach to effectively approximate the total force on each ion during a trajectory calculation in mass spectrometry device simulations, and the algorithm worked successfully with SIMION. We took one step further and applied the method in massively parallel general-purpose computing with GPU (GPGPU) to test its performance in simulations with thousands to over a million ions. We took extra care to minimize the barrier synchronization and data transfer between the host (CPU) and the device (GPU) memory, and took full advantage of the latency hiding. Parallel codes were written in CUDA C++ and implemented to SIMION via the user-defined Lua program. In this study, we tested the parallel hybrid algorithm with a couple of basic models and analyzed the performance by comparing it to that of the original, fully-explicit method written in serial code. The Coulomb explosion simulation with 128,000 ions was completed in 309 s, over 700 times faster than the 63 h taken by the original explicit method in which we evaluated two-body Coulomb interactions explicitly on one ion with each of all the other ions. The simulation of 1,024,000 ions was completed in 2650 s. In another example, we applied the hybrid method on a simulation of ions in a simple quadrupole ion storage model with 100,000 ions, and it only took less than 10 d. Based on our estimate, the same simulation is expected to take 5–7 y by the explicit method in serial code.
Which surfactants reduce surface tension faster? A scaling argument for diffusion-controlled adsorption

Consider the example of surfactant adsorbing from an infinite solution to a freshly formed planar interface. There is an implicit length scale in this problem, the adsorption depth h, which is the depth depleted to supply the interface with the adsorbed surfactant. From a mass balance, h can be shown to be the ratio of the equilibrium surface concentration Γeq to the bulk concentration C∞. The characteristic time scale for diffusion to the interface is τD=h2/D, where D is the diffusivity of the surfactant in solution. The significance of this time scale is demonstrated by numerically integrating the equations governing diffusion-controlled adsorption to a planar interface. The surface tension equilibrates within 1–10 times τD regardless of bulk concentration, even for surfactants with strong interactions. Dynamic surface tension data obtained by pendant bubble method are rescaled using τD to scale time. For high enough bulk concentrations, the re-normalized surface tension evolutions nearly superpose, demonstrating that τD is indeed the relevant time scale for this process. Surface tension evolutions for a variety of surfactants are compared. Those with the smallest values for τD equilibrate fastest. Since diffusion coefficients vary only weakly for surfactants of similar size, the differences in the equilibration times for various surfactant solutions can be attributed to their differing adsorption depths. These depths are determined by the equilibrium adsorption isotherms, allowing τD to be calculated a priori from equilibrium surface tension data, and surfactant solutions to be sorted in terms of which will reduce the surface tension more rapidly. Finally, trends predicted by τD to gauge what surfactant properties are required for rapid surface tension reduction are discussed. These trends are shown to be in agreement with guiding principles that have been suggested from prior structure–property studies.
Expression, purification, and enzymatic characterization of a protein A-β-lactamase hybrid protein

Abstract The genes for the enzyme TEM-β-lactamase and Staphylococcus aureus protein A were fused in-frame and expressed in E. coli. The resulting bifunctional polypeptide was secreted through the inner membrane but remained partially associated with the cell envelope. The hybrid protein was very susceptible to degradation, and, as a result, production in strain HB101 was low. It was demonstrated that proteolytic degradation occurs primarily within the β-lactamase domain of the hybrid protein. Expression in E. coli strain KS474, which is deficient in periplasmic proteases, resulted in 40-fold higher production. The hybrid protein was purified from strain KS474 and its catalytic characteristics were compared with β-lactamase. The latter was purified to apparent homogeneity using a new procedure based on the refolding of inclusion body protein. The hybrid protein and β-lactamase exhibited very similar kinetic parameters for the hydrolysis of benzylpenicillin and cephaloridine, indicating that the catalytic properties were essentially unperturbed by the fusion of protein A. The binding constant for the association of the hybrid protein with rabbit IgG in solution was equal to 1.4 × 10−7 M. This value is comparable to that obtained with the intact protein A. It was also demonstrated that protein A-β-lactamase can be immobilized on IgG sepharose with retention of the enzymatic activity.
Comparative Physical Modes of Action of Azoxystrobin, Mancozeb, and Metalaxyl Against Plasmopara viticola (Grapevine Downy Mildew)

The physical modes of action of azoxystrobin, mancozeb, and metalaxyl were evaluated on grapevine seedlings using Plasmopara viticola as a model pathogen. The protectant, postinfection, postsymptom, translaminar, and vapor activities of azoxystrobin were evaluated at a rate of 250 μg/ml. Azoxystrobin provided 100% disease control when applied 1 to 5 days before inoculation. Postinfection applications of azoxystrobin had little effect on the incidence of disease, but colony area and sporulation from the resultant lesions was reduced by 47 and 96%, respectively, relative to the check treatment when applied up to 5 days after inoculation. Postsymptom applications (6 days after inoculation) of azoxystrobin resulted in an 85% mean reduction of resporulation from diseased tissue relative to the check when seedlings were evaluated 1 to 14 days after treatment. Translaminar activity was greatest when the upper surface of the leaf was treated 7 days before inoculation of the lower leaf surface (94% disease control). In contrast, control was <50% when leaves were similarly inoculated 1 and 3 days after treatment. Vapor activity was not pronounced, providing maximum reductions of 5, 11, and 37%, with regard to incidence, colony area, and sporulation, relative to the check when seedlings were treated 1 to 7 days before inoculating adjacent, untreated leaves. Comparatively, mancozeb (1,790 μg/ml) provided complete control of the disease when applied 1 to 5 days before inoculation, but showed little postinfection activity in reducing disease incidence, although it exhibited moderate to high antisporulant activity when applied in postinfection and postsymptom modes (mean reductions of 38 and 89%, respectively, compared with the check treatments). Metalaxyl (260 μg/ml) also provided complete control of the disease when used in protectant mode, and also when applied 1 day after inoculation. Applications at 3 to 5 days after inoculation provided substantial reductions in disease severity and sporulation (mean reductions of 46 and 94%, respectively, compared with the check treatments), and postsymptom applications resulted in a mean 84% reduction in resporulation. Collectively, the results of this study illustrate the unique physical modes of action for azoxystrobin in comparison to that of two traditional protectant and systemic fungicides, and provide information on how azoxystrobin and other strobilurin fungicides with similar physical modes of action should be best used in disease management programs.
Adhesion-dependent regulation of p190RhoGAP in the developing brain by the Abl-related gene tyrosine kinase.

Abstract Abl family kinases, which include the mammalian Abl and Arg (Abl-related gene) kinases, regulate neuronal morphogenesis in developing metazoa (for review, see [1]). Activation of Abl kinase activity directs changes in actin-dependent processes such as membrane ruffling, filopodial protrusion, and cell motility [2–6]. However, the mechanisms by which increased Abl or Arg kinase activity promote cytoskeletal rearrangements are unclear. We provide evidence that the Rho inhibitor p190RhoGAP ( G TPase- a ctivating p rotein) is an Arg substrate in the postnatal mouse brain. We show that p190RhoGAP has reduced phosphotyrosine content in postnatal arg −/− mouse brain extracts relative to wild-type extracts. In addition, the adhesion-dependent stimulation of p190RhoGAP phosphorylation observed in wild-type cells is not observed in arg −/− fibroblasts and neurons. Arg can phosphorylate p190RhoGAP in vitro and in vivo on tyrosine (Y) 1105. We find that Arg can stimulate p190RhoGAP to inhibit Rho and that Arg-mediated phosphorylation is required for this stimulation. Phosphorylation by Arg also promotes p190RhoGAP's association with p120RasGAP and stimulates p190RhoGAP's ability to induce neuritogenesis in neuroblastoma cells. Our results demonstrate that p190RhoGAP is an Arg substrate in the developing brain and suggest that Arg mediates the adhesion-dependent regulation of neuronal morphogenesis in the postnatal brain by phosphorylating p190RhoGAP.
Synthesis of multiwalled carbon nanotubes through a modified Wolff-Kishner reduction process.

We report the synthesis of highly crystallized multiwalled carbon nanotubes through a modified Wolff−Kishner reduction process at a low temperature of 180 °C without adding the conventional catalysts of Fe/Co/Ni into the reaction vessel. The as-synthesized carbon nanotubes are about 10−40 nm in diameter and several tens of micrometers in length. The experimental results indicate that a high concentration of NaOH is essential to the formation of carbon nanotubes. This technique opens a new route for the synthesis of CNTs and other carbon nanostructured materials.