cssi/SciSciGPT-SciSciNet huggingface dataset:
A study of statistics knowledge among nurse faculty in schools with research doctorate programs.

Abstract Statistics knowledge is essential for nursing faculty in both teaching and research roles. In the teaching role when discussing nursing research, nursing faculty are confronted with statistical concepts and statistical methods applications. Knowledge of fundamental statistical concepts is needed so that nursing faculty can understand and critically evaluate the literature. The purpose of this study was to assess nursing faculty knowledge of fundamental statistical concepts. A probability sample with a 7.7% response rate yielded participation from 164 nursing faculty from 26 accredited schools. Results showed that most faculty members (91.5%) read peer-reviewed health-related scientific journal articles. On average, nursing faculty answered 5.1 (SD = 1.6) out of 8 statistical knowledge questions correctly. Problematic concepts included randomization (43.3% correct), and interpreting a confidence interval (42.7%) and odds ratio (33.5%). The results of this study may be used to improve statistics education and training for future nursing faculty and strengthen scholarship for nursing faculty conducting research.
Cartwright on Explanation and Idealization

Nancy Cartwright (1983, 1999) argues that (1) the fundamental laws of physics are true when and only when appropriate ceteris paribus modifiers are attached and that (2) ceteris paribus modifiers describe conditions that are almost never satisfied. She concludes that when the fundamental laws of physics are true, they don’t apply in the real world, but only in highly idealized counterfactual situations. In this paper, we argue that (1) and (2) together with an assumption about contraposition entail the opposite conclusion — that the fundamental laws of physics do apply in the real world. Cartwright extracts from her thesis about the inapplicability of fundamental laws the conclusion that they cannot figure in covering-law explanations. We construct a different argument for a related conclusion — that forward-directed idealized dynamical laws cannot provide covering-law explanations that are causal. This argument is neutral on whether the assumption about contraposition is true. We then discuss Cartwright’s simulacrum account of explanation, which seeks to describe how idealized laws can be explanatory.
Management of severe epistaxis after Young's procedure: a case report

Background Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder affecting multiple organ systems, with epistaxis being the most common manifestation. Multiple procedures have been used for the management of epistaxis in the setting of HHT, including closure of the anterior nares via a Young's procedure. While this procedure results in loss of smell and permanent nasal obstruction, proponents note significant improvement in patient symptomatology. Methods Case report. Results A 70-year-old female with a history of HHT presented to an outside hospital with bleeding into the nasopharynx 2 months after undergoing a modified Young's procedure at an unaffiliated institution. She was transfused with 2 units of packed red blood cells (PRBCs) and transferred to our facility. Due to persistent epistaxis and need for airway protection, the patient was intubated and her throat was packed. She also developed aspiration pneumonia and hypotensive shock requiring vasopressors. Twenty-four hours following bilateral internal maxillary and sphenopalatine artery embolization, she developed significant epistaxis requiring reversal of the Young's procedure on the left and placement of an anterior-posterior pack at the bedside. Upon packing removal several days later in the operating room, she was noted to have significant bleeding that necessitated reversal of the Young's procedure on the right side to obtain adequate exposure and hemostasis. Conclusion We report a case of significant, life-threatening epistaxis following a modified Young's procedure that requiring multiple transfusions, bilateral embolization, and ultimately reversal of the Young's procedure for control of epistaxis. Although recognized as a potential complication, to our knowledge this is the first report in the English literature of such a case.
Overexpression of Serum Amyloid A-Activating Factor 1 Inhibits Cell Proliferation by the Induction of Cyclin-Dependent Protein Kinase Inhibitor p21WAF-1/Cip-1/Sdi-1 Expression

Inflammation-responsive transcription factor, serum amyloid A-activating factor 1 (SAF-1), has been shown to regulate several genes, including serum amyloid A, γ-fibrinogen, and matrix metalloproteinase 1, whose abnormal expression is associated with the pathogenesis of arthritis, atherosclerosis, and amyloidosis. Prolonged high level expression of SAF-1 in cultured cells failed to produce any stable cell line that overexpresses SAF-1. To test the fate of SAF-1-overexpressing cells, the cells were monitored for growth and morphological changes over time. The cells that were programmed to overproduce SAF-1 were found to undergo growth arrest and reduce DNA synthesis within 3 days after transfection. These cells undergo marked morphological changes from typical fibroblasts to round morphology and gradually cease to exist. Microarray analysis for cell cycle-specific genes in SAF1-transfected cells identified several candidate genes whose expression levels were altered during SAF-1 overexpression. Cdk inhibitor protein p21 was significantly affected by SAF-1; its expression level was highly induced by cellular conditions where SAF-1 is abundant. The increased level of p21 in the cell drives it to a growth arrest mode, a condition previously found to be controlled by p53. In this study we provide evidence that, similar to p53, SAF-1 is able to activate p21 gene expression by promoting transcription directly via its interaction with the p21 promoter. Together these data indicate that SAF-1 controls cell cycle progression via p21 induction, and pathophysiological conditions that favor overexpression of SAF-1, such as an acute inflammatory condition, can trigger cellular growth arrest.
A Promoter Haplotype of the Immunoreceptor Tyrosine-Based Inhibitory Motif-Bearing FcγRIIb Alters Receptor Expression and Associates with Autoimmunity. I. Regulatory FCGR2B Polymorphisms and Their Association with Systemic Lupus Erythematosus

FcγRIIb, the immunoreceptor tyrosine-based inhibitory motif-containing receptor for IgG (Mendelian Inheritance in Man no. 604590), plays an important role in maintaining the homeostasis of immune responses. We have identified 10 novel single-nucleotide polymorphisms in the promoter region of human FCGR2B gene and characterized two functionally distinct haplotypes in its proximal promoter. In luciferase reporter assays, the less frequent promoter haplotype leads to increased expression of the reporter gene in both B lymphoid and myeloid cell lines under constitutive and stimulated conditions. Four independent genome-wide scans support linkage of the human FcγR region to the systemic lupus erythematosus (SLE; Online Mendelian Inheritance in Man no. 152700) phenotype. Our case-control study in 600 Caucasians indicates a significant association of the less frequent FCGR2B promoter haplotype with the SLE phenotype (odds ratio = 1.65; p = 0.0054). The FCGR2B haplotype has no linkage disequilibrium with previously identified FCGR2A and FCGR3A polymorphisms, and after adjustment for FCGR2A and FCGR3A , FCGR2B showed a persistent association with SLE (odds ratio = 1.72; p = 0.0083). These results suggest that an expression variant of FCGR2B is a risk factor for human lupus and implicate FCGR2B in disease pathogenesis.
“If you are not pleased to favor me, put me out of your mind…”: Gender and authority in Sor Juana Inés de la Cruz: And the Translation of her letter to the Reverend Father Maestro Antonio Núñez of the Society of Jesus

Abstract In 1980, Monsignor Aureliano Tapia Mendez found a heretofore unknown letter by the Mexican nun Sor Juana Ines de la Cruz to her Jesuit confessor, Father Antonio Nunez. Critics have estimated that the letter was written about 1681, 10 years before her later and more famous “Reply to Sister Philotea,” one of the first feminist defenses of the right of women to an intellectual vocation. This letter is even more explicit in her defiance of patriarchal and ecclesiastical authority over her person, her soul, and the life of her mind.
Regulation of serine transhydroxymethylase activity in Salmonella typhimurium.

The regulation of serine transhydroxymethylase (EC 2.1.2.1.; l-serine:tetrahydrofolic-5,10-hydroxymethyltransferase) has been investigated in Salmonella typhimurium LT2. Our results indicate that limitation of a methionine auxotroph for methionine does not cause derepression of this enzyme as reported for Escherichia coli. However, a sixfold decrease in specific activity was observed when S. typhimurium cells were grown in glucose minimal medium supplemented with serine, glycine, methionine, adenine, guanine, and thymine. None of these compounds added to the growth medium individually produced more than a 42% reduction of wild-type enzyme activity. This enhanced repression by the combination of compounds suggests a form of cumulative repression of this enzyme. Growth of serine and thymine auxotrophs, with the respective requirement of each limiting, did not result in increased enzyme activity. However, growth of a purine auxotroph with a limiting amount of either guanine or inosine resulted in a five- to sevenfold increase in enzyme activity. A second condition causing significant derepression (fourfold increase) above the levels observed with cells grown in minimal medium was the addition of 0.5 μg of trimethoprim per ml, an inhibitor of the dihydrofolate reductase activity. (A partial report on this work was presented at 1974 meeting of the American Society for Microbiology.)
The use of design of experiments to evaluate the reliability of ferroelectric nonvolatile memories

A full factorial experiment was performed on 4 K ferroelectric random access memory (FRAM) devices to determine their fatigue performance as a function of fatigue temperature, fatigue voltage, read/write voltage, pattern, and number of cycles of fatigue. The resulting response surface of short-term retention (10 s at 80 degrees C) and long-term retention (40 h at 100 degrees C) and the product functionality were the metrics used to evaluate the product performance. An empirical model was used to predict yields and product performance. Based on this model, process modifications were undertaken to improve the performance of the product fabricated with PZT (nominal composition: Pb/sub 1.10/Zr/sub 0.48/Ti/sub 0.52/O/sub 3/. As a result, better than two-orders-of-magnitude improvement in product performance over operating conditions was seen. In addition, a statistically based monitoring program has been developed to ensure product performance. >
Hydrogen sensor based on palladium nanowire array

In this work palladium nanowire arrays have been studied for hydrogen gas sensing applications at room temperature. These parallel arrays of Pd nanowires were fabricated by electrode position from an aqueous plating solution onto an HOPG surface. The nanowires were then transferred onto a polymer film and silver electrical contact pads were fabricated by shadow masking. The morphology of the nanowires was analyzed using atomic force microscope (AFM) and the diameter of the observed nanowires was measured to be approximately 250 nm. Scanning electron microscope (SEM) images revealed that the nanowires fabricated by this procedure were mostly parallel and continuous. Experimental results indicated that the sensors are highly sensitive to Hydrogen, showing a two-order change in conductance. SEM images showed that the nanowires contain nanogaps in absence of H/sub 2/. On, exposure to H/sub 2/ palladium absorbed hydrogen resulting in the expansion of Pd grains. This expansion results in the closing of the nanogaps.
LOW PROTEIN DIETS INCREASE NEUROPEPTIDE Y GENE EXPRESSION IN THE BASOMEDIAL HYPOTHALAMUS OF RATS

Food deprivation elevates both neuropeptide Y (NPY) gene expression in the basomedial hypothalamus and NPY levels in the paraventricular nucleus (PVN). To gain a better understanding of the dietary control of NPY, we systematically examined the effects of macronutrient restriction on the gene expression of NPY in the basomedial hypothalamus and NPY content in the PVN. Rats were fed one of eight different diets for 12 d. The control group was fed a modified AIN-76 diet. One group was fed the modified AIN-76 diet but was restricted in energy by 50%. Six isocaloric (to the control diet) test diets were prepared, each with an individual macronutrient reduced by 50%. Neuropeptide Y gene expression was elevated in protein-restricted animals as well as in energy-restricted animals. Carbohydrate or fat restriction seemed to have no effect on NPY gene expression. Though the NPY content in the PVN was not different between any groups, two findings were consistent with greater NPY release in protein-restricted animals. Animals fed a low protein diet were hyperphagic and had a greater amount of body fat. This study suggests that low levels of dietary protein may have a role in the regulation of NPY gene expression.
Integrating smoking cessation and alcohol use treatment in homeless populations: study protocol for a randomized controlled trial

Despite progress in reducing cigarette smoking in the general U.S. population, smoking rates, cancer morbidity and related heart disease remain strikingly high among the poor and underserved. Homeless individuals’ cigarette smoking rate remains an alarming 70 % or greater, and this population is generally untreated with smoking cessation interventions. Furthermore, the majority of homeless smokers also abuse alcohol and other drugs, which makes quitting more difficult and magnifies the health consequences of tobacco use. Participants will be randomized to one of three groups, including (1) an integrated intensive smoking plus alcohol intervention using cognitive behavioral therapy (CBT), (2) intensive smoking intervention using CBT or (3) usual care (i.e., brief smoking cessation and brief alcohol counseling). All participants will receive 12-week treatment with a nicotine patch plus nicotine gum or lozenge. Counseling will include weekly individual sessions for 3 months, followed by monthly booster group sessions for 3 months. The primary smoking outcome is cotinine-verified 7-day smoking abstinence at follow-up week 52, and the primary alcohol outcome will be breathalyzer-verified 90-day alcohol abstinence at week 52. This study protocol describes the design of the first community-based controlled trial (n = 645) designed to examine the efficacy of integrating alcohol abuse treatment with smoking cessation among homeless smokers. To further address the gap in effectiveness of evidence-based smoking cessation interventions in the homeless population, we are conducting a renewed smoking cessation clinical trial called Power to Quit among smokers experiencing homelessness. ClinicalTrials.gov Identifier: NCT01932996 . Date of registration: 20 November 2014.
Artificial neural network simulation of battery performance

Although they appear deceptively simple, batteries embody a complex set of interacting physical and chemical processes. While the discrete engineering characteristics of a battery, such as the physical dimensions of the individual components, are relatively straightforward to define explicitly, their myriad chemical and physical processes, including interactions, are much more difficult to accurately represent. For this reason, development of analytical models that can consistently predict the performance of a battery has only been partially successful, even though significant resources have been applied to this problem. As an alternative approach, we have begun development of non-phenomenological models for battery systems based on artificial neural networks. The paper describes initial feasibility studies as well as current models and makes comparisons between predicted and actual performance.
Yeast Ste23p shares functional similarities with mammalian insulin-degrading enzymes.

The S. cerevisiae genome encodes two M16A enzymes: Axl1p and Ste23p. Of the two, Ste23p shares significantly higher sequence identity with M16A enzymes from other species, including mammalian insulin-degrading enzymes (IDEs). In this study, recombinant Ste23p and R. norvegicus IDE (RnIDE) were isolated from E. coli, and their enzymatic properties compared. Ste23p was found to cleave established RnIDE substrates, including the amyloid-β peptide (Aβ1–40) and insulin B-chain. A novel internally quenched fluorogenic substrate (Abz–SEKKDNYIIKGV–nitroY-OH) based on the polypeptide sequence of the yeast P2 a-factor mating propheromone was determined to be a suitable substrate for both Ste23p and RnIDE, and was used to conduct comparative enzymological studies. Both enzymes were most active at 37 °C, in alkaline buffers and in high salt environments. In addition, the proteolytic activities of both enzymes towards the fluorogenic substrate were inhibited by metal chelators, thiol modifiers, inhibitors of cysteine protease activity and insulin. Characteristics of STE23 expression were also evaluated. Our analysis indicates that the 5′ terminus of the STE23 gene has been mischaracterized, with the physiologically relevant initiator corresponding to residue M53 of the publicly annotated protein sequence. Finally, we demonstrate that, unlike haploid-specific Axl1p, Ste23p is expressed in both haploid and diploid cell types. Our study presents the first comprehensive biochemical analysis of a yeast M16A enzyme, and provides evidence that S. cerevisiae Ste23p has enzymatic properties that are highly consistent with mammalian IDEs and other M16A enzymes. Copyright © 2009 John Wiley & Sons, Ltd.
IT Failure Rates - 70% or 10-15%?

This is a closed-book quiz. Quick, now - what percentage of software projects fail? Let me hazard a guess as to your answer. Odds are, you said something like "70 percent." Am I right? Now, I want to analyze why you said whatever you said. A friend of mine, Nicholas Zvegintzov (the Chief Guru of software maintenance), likes to say that, if you track down the sources of the things we "know" in our field, you'll find that what we thought was a plethora of sources for that knowledge generally boils down to only a precious few. That raises the question "Where do we get our information on software failure rates?" I've seen software failure trumpeted from so many academic research papers that I had to quit counting (they tend to see a "software crisis" and then say that the research work they're describing will help eliminate it). However, if you closely examine the citations they use to support the claims of crisis, over and over again the citations boil down to one primary source, the Standish Chaos Reports. And, if you take matters one step further, the papers generally cite the 1994 report. I want to question the unquestionable status of that Standish report. That's because, you see, my own observations lead me to believe that something is terribly wrong with those Standish findings.
The growth of the mean average crossing number of equilateral polygons in confinement

The physical and biological properties of collapsed long polymer chains as well as of highly condensed biopolymers (such as DNA in all organisms) are known to be determined, at least in part, by their topological and geometrical properties. With this purpose of characterizing the topological properties of such condensed systems equilateral random polygons restricted to confined volumes are often used. However, very few analytical results are known. In this paper, we investigate the effect of volume confinement on the mean average crossing number (ACN) of equilateral random polygons. The mean ACN of knots and links under confinement provides a simple alternative measurement for the topological complexity of knots and links in the statistical sense. For an equilateral random polygon of n segments without any volume confinement constrain, it is known that its mean ACN ACN is of the order . Here we model the confining volume as a simple sphere of radius R. We provide an analytical argument which shows that ACN of an equilateral random polygon of n segments under extreme confinement (meaning R n) grows as O(n2). We propose to model the growth of ACN as a(R)n2 + b(R)nln(n) under a less-extreme confinement condition, where a(R) and b(R) are functions of R with R being the radius of the confining sphere. Computer simulations performed show a fairly good fit using this model.
Effects of H2 Additions on Stress Corrosion Cracking in a Boiling Water Reactor

Abstract Controlled amounts of hydrogen were injected into the Dresden-2 boiling water reactor (BWR) during a five week period. The effect of the hydrogen modifed water chemistry on major structura...
“Recovered-memory” therapy: Profession at a turning point

Six hundred Massachusetts-registered psychiatrists were surveyed for their opinions on items plausibly related to the production of false memories of childhood sexual abuse. One hundred fifty-four psychiatrists completed the written questionnaire. A majority of respondents (69%) endorsed the following statement: "The numbers of false accusations of childhood sexual abuse, appearing to emerge from the psychotherapy of adults, constitute a real problem needing public acknowledgment as such by the mental health professions." Nevertheless, a substantial minority endorsed the following practices: 37% endorsed searching for childhood roots of presenting complaints; 36% endorsed validation (expressed belief) of the patient's memories as an essential part of therapy; 36% believed in appropriateness of affect as an indicator of truth in memories; 36% believed in the therapeutic value of abreaction; 26% would refer presumed survivors of abuse to specialists in incest recovery; 18% believed in ritual abuse as an important cause of posttraumatic stress disorder (PTSD) and dissociative disorders; 18% trusted symptom checklists as indicators of sexual abuse histories; and 15% believed that memory is a complete record of the individual's history. Small minorities (6% to 8%) endorsed these practices: using hypnosis to gain access to repressed memories of childhood abuse; patient confrontation of alleged abusers; and recommending the severing of contacts with skeptical family members. A factor analysis was performed, and it was found that self-designated specialists were more likely than nonspecialists to score toward the riskier pole of the four factors extracted.
Transapical approach for mitral valve repair during insertion of a left ventricular assist device.

Background. Severe mitral regurgitation (MR) is common in patients who are undergoing insertion of a left ventricular assist device (LVAD). This study analyzes the outcomes of a transapical approach for edge-to-edge repair of the mitral valve during insertion of a left ventricular assist device in 19 patients with MR. Methods. This retrospective study includes 19 patients who were implanted between March 21, 2011, and August 31, 2011, at the University of Chicago. Clinical data include preoperative ejection fraction, post- and preoperative pulmonary arterial pressures, cardiopulmonary bypass time, post- and preoperative mitral regurgitation severity, endotracheal CO2, and LVAD pulse index. Results. All of the 19 patients had a reduction in mitral regurgitation. Fourteen of the 19 patients had at least a three-point reduction in MR severity. The average postoperative pulmonary arterial pressure (PAP) decreased after the surgical procedure from 44/22 ± 14/5 mmHg to 57/28 ± 9/5 mmHg. Average CPB time was 128 ± 27 minutes. Average length-of-stay (LOS) was 21 ± 10 days. Conclusions. Concomitant MV repair using a transapical approach is advantageous for this small cohort of patients. The surgical procedure is less complex and has a shorter CPB time and LOS, and all of the patients demonstrated significant improvement in postoperative MR and moderate improvement in PAP.
Excitatory and inhibitory effects of serotonin on sensorimotor reactivity measured with acoustic startle

Serotonin infused into the lateral ventricle in rats produced a dose-dependent depression of the acoustic startle reflex. When infused onto the spinal cord, serotonin produced a dose-dependent increase in startle. Thus the same neurotransmitter can modulate the same behavior in opposite ways, depending on which part of the central nervous system is involved.
Suppression of protein degradation in progressive cardiac hypertrophy of chronic aortic regurgitation.

BACKGROUNDThe heart adapts to the volume overload of aortic regurgitation with dilation and hypertrophy. The development of left ventricular hypertrophy at the protein level is a dynamic process resulting from an imbalance between cardiac protein synthesis and degradation. The objective of the present study was to determine in vivo the relative contributions of cardiac protein synthesis and degradation to the progressive hypertrophy that occurs in response to chronic aortic regurgitation and to compare these with responses earlier in the course of this stress.METHODS AND RESULTSContinuous intravenous infusions of [3H]-leucine were administered 3 days and 1 month after surgical induction of aortic regurgitation and sham operation in rabbits. Total cardiac protein and myosin heavy chain fractional synthesis rates were obtained by analysis of plasma and protein hydrolysate data using [14C]-dansyl chloride assays. Left ventricular growth rates were determined from serial echocardiographic and postmortem left ...
Public Relations for Advanced Practice Nurses

Public relations (PR) is one aspect of successful business that can be used effectively by advanced practice nurses (APNs) to promote themselves as health care providers within their communities.
Geometric modeling of geospatial data for visualization-assisted excavation

Underground utility lines being struck by mechanized excavators during construction or maintenance operations is a long standing problem. Besides the disruptions to public services, daily life, and commerce, utility strike accidents lead to injuries, fatalities, and property damages that cause significant financial loss. Utility strikes by excavation occur mainly because of the lack of an effective approach to synergize the geospatial utility locations and the movement of excavation equipment into a real-time, three-dimensional (3D) spatial context that is accessible to excavator operators. A critical aspect of enabling such a knowledge-based excavation approach is the geospatial utility data and its geometric modeling. Inaccurate and/or incomplete utility location information could lead to false instilled confidence and be counterproductive to the excavator operator. This paper addresses the computational details in geometric modeling of geospatial utility data for 3D visualization and proximity monitoring to support knowledge-based excavation. The details of the various stages in the life-cycle of underground utility geospatial data are described, and the inherent limitations that preclude the effective use of the data in downstream engineering applications such as excavation guidance are analyzed. Five key requirements - Interactivity, Information Richness, 3-Dimensionality, Accuracy Characterization, and Extensibility - are identified as necessary for the consumption of geospatial utility data in location-sensitive engineering applications. A visualization framework named IDEAL that meets the outlined requirements is developed and presented in this paper to geometrically represent buried utility geospatial data and the movement of excavation equipment in a 3D emulated environment in real-time.
Photonic-crystal-diaphragm-based fiber-tip hydrophone optimized for ocean acoustics

We report a miniature fiber hydrophone that consists of a Fabry-Perot interferometer made of a photonic-crystal reflector embedded on a compliant silicon diaphragm placed at the tip of a single-mode fiber. A model was developed to show that after proper optimization to ocean acoustics, this sensor has a minimum detectable pressure that follows the minimum ambient noise of the ocean (reaching a minimum of ~10 μPa/Hz 1/2 at ~30 kHz) in the bandwidth of 1 Hz-100 kHz. By placing several such sensors with different acoustic power ranges within a single hydrophone head, the hydrophone is able of exhibiting a dynamic range in the excess of 200 dB. A prototype was fabricated, assembled, and tested that confirmed this high sensitivity and bandwidth.
A Gas Sample Pre-concentration Device Based on Solid Phase Microextraction (SPME) and Temperature Programmed Desorption (TPD)

Abstract A sample pre‐concentration device, based on solid phase microextraction (SPME) fiber and temperature programmed desorption (TPD), was developed and tested in the analysis of volatile organic compounds. The pre‐concentrator device consists of a low dead volume quartz tube that houses the SPME fiber during the extraction/ desorption steps, a Ni:Cr heating element, and a programmable power supply. Compounds are extracted from air into the SPME fiber according to their affinity and solubility to the fiber material. Following this extraction step, samples are desorbed by a pre‐programmed temperature ramp for their subsequent detection. The SPME fiber was exposed and sample extracted for a pre‐determined amount of time (1 min, in this work). Because of the limited specificity of the stationary phase in SPME fibers towards the analyte, background interfering compounds are unavoidably co‐extracted during this process. A TPD step was then applied to sequentially desorb and detect analytes and interference...
An approximate method of solution for the inverse problem

One approach to solving the inverse problem is to find and then use off-shell T matrices in the inverse equation V= T + TGin0itT. It is shown that near the energy shell the off-shell T matrix may be approximated by an on-shell T matrix at a common value of the momentum transfer q = ¦k − k″¦. At forward scattering angles, we fix the magnitude of q and k, while at back angles we fix the magnitude and direction of q. This method is illustrated graphically.
Pica and Olfactory Craving of Pregnancy: How Deep Are the Secrets?

The practice of pica during pregnancy is described in contemporary literature as the ingestion of nonfood substances and food staples in response to craving. A previously unnamed practice, olfactory craving of pregnancy, is the smelling by pregnant women of selected substances in response to craving, which may occur alone or with pica. Observations and descriptions of women's experiences of pica and olfactory craving were documented during individualized postpartum bedside instruction of 300 women at a midwestern hospital between 1992 and 1994. Most women were African American and low income. Eight themes about pica of pregnancy were keeping practices secret, singularity of the experience, obtaining the craved substance, fears for effects on the fetus, yielding or not yielding to cravings, use of substances as medication, pica and food intake, and sensory experiences other than taste. Three themes about olfactory craving of pregnancy were changes in sense of smell during pregnancy, types of craved substances and settings, and escalation in use during pregnancy. The clinical stages of pica and olfactory craving require further investigation, and perinatal caregivers have to seek and remove the barriers that cause pregnant women to isolate themselves with the practices that stem from these cravings.
Control of phospholipid synthesis and viral assembly by bacteriophage PM2.

Abstract The control of phospholipid synthesis exerted by the lipid-containing bacteriophage PM2 was studied by employing a glycerol-requiring auxotroph of the host cell Pseudomonas BAL-31. Double-isotope, pulse-label experiments suggest that cellular phospholipid polar groups are cleaved and replaced by glycerol during infection. A temperature sensitive virus mutant was isolated which cannot effect this polar group conversion at its restrictive temperature, 31.5 °C. This mutant lyses infected cells at 31.5 °C, but no stable virus particles are formed. This suggest that the phospholipid polar group conversion may be an essential feature for viral assembly in this system.
Alterations in metal toxicity and metal-induced metallothionein gene expression elicited by growth medium calcium concentration

The calcium content of the growth medium has been shown to influence the growth and differentiation of primary epithelial cells in culture. The goal of the present study was to determine if growth medium calcium concentration could influence the susceptibility to metal toxicity and metallothionein gene expression of an immortalized human prostate-derived epithelial cell line (RWPE-1). The RWPE-1 cell line was grown in medium containing either 0.1 or 1.4 mM calcium. Confluent cells were exposed to either Zn(+2) (50, 100, or 150 microM) or Cd(+2) (3, 6, or 12 microM) for 13 days, and cell toxicity and MT gene expression were determined along the time course of exposure. It was demonstrated that the calcium content of the growth medium had a marked influence on Zn(+2) toxicity and a lesser but significant effect on Cd(+2) toxicity to the RWPE-1 cells. Calcium concentration of the growth medium was also shown to alter the accumulation of MT-1/2 protein and MT-1E, MT-1X, and MT-2A mRNAs. It was shown that MT-1/2 protein was markedly increased for metal-exposed cells grown in medium containing 0.1 mM calcium; however, the increased expression did not cause an increase in the resistance of the cells to Zn(+2) or Cd(+2) exposure. These observations show that growth medium calcium concentration can influence metal toxicity and the pattern of expression of the MT mRNAs and protein for RWPE-1 cells. The results suggest that caution should be exercised when comparing toxicological responses between cell lines that may be grown in growth formulations differing in calcium concentration.
A Denervated Nonfiltering Kidney Preparation in the Rat: A Model for Study of Renin Release:

To examine the role of the renal vascular receptor in the control of renin secretion in the rat, a denervated, nonfiltering kidney model (DNFK) was developed. The left kidney was subjected to a 2-hr period of total renal ischemia followed by ureteral ligation and section Denervation was accomplished by stripping all visible nerves and painting the renal vessels with 5% phenol. Forty-eight hours later lissamine green dye was injected iv and failed to appear in either the cortical or medullary tubules, indicating that glomerular filtration had ceased. Histological study of these kidneys revealed diffuse tubular necrosis with extensive intratubular cast formation. Norepinephrine content of the DNFK was reduced 91% compared to the contralateral normal kidney (P less than 0.001). In another group of anesthetized rats with a single DNFK, 15 min of suprarenal aortic constriction (SAC) increased plasma renin activity (PRA) from 3.4 +/- 0.6 to 11.5 +/- 1.6 ng AI/ml/hr; in a time control series, PRA was unchanged. To exclude the influence of adrenal catecholamines in this response, bilateral adrenalectomy was performed in a separate group of animals with a DNFK. In this series, SAC also markedly increased PRA. The present data indicate that in the rat the macula densa, the renal nerves, and adrenal catecholamines were not essential for the hyperreninemia induced by a reduction in renal perfusion pressure.
Cardiac Resynchronization Therapy for the Management of Chronic Heart Failure

While numerous pathophysiologic mechanisms may lead to the onset and progression of chronic systolic heart failure, a variety of electrophysiologic abnormalities seen in the setting of chronic left ventricular dysfunction may also contribute to the natural history of the disease. Atrial, atrial-ventricular, and inter- and intraventricular conduction disturbances may place the failing ventricle at a further mechanical disadvantage, thus contributing to the functional impairment and poor outcomes associated with chronic heart failure. In the early 1990s, attempts at treating patients with end-stage systolic heart failure using conventional pacing strategies met with equivocal results. However, this work did provide further insight into the electromechanical consequences of advanced heart failure and suggested that atrial-synchronized biventricular pacing, or cardiac resynchronization therapy, might provide better and more consistent symptomatic and hemodynamic improvement. Several landmark clinical trials have evaluated the safety and efficacy of cardiac resynchronization therapy in New York Heart Association (NYHA) class III and IV heart failure. These studies have consistently shown statistically significant improvements in quality of life, NYHA functional class ranking, exercise tolerance, and left ventricular reverse remodeling. Some studies have suggested reductions in morbidity and mortality. This latter observation has been confirmed by a recent large-scale outcomes study. Thus, cardiac resynchronization therapy should be routinely considered in eligible NYHA class III and IV heart failure patients with ventricular dyssynchrony.
A preliminary set of applications leading to stochastic semidefinite programs and chance-constrained semidefinite programs

Ariyawansa and Zhu have recently introduced (two-stage) stochastic semidefinite programs (with recourse) (SSDPs) [1] and chance-constrained semidefinite programs (CCSDPs) [2] as paradigms for dealing with uncertainty in applications leading to semidefinite programs. Semidefinite programs have been the subject of intense research during the past 15 years, and one of the reasons for this research activity is the novelty and variety of applications of semidefinite programs. This research activity has produced, among other things, efficient interior point algorithms for semidefinite programs. Semidefinite programs however are defined using deterministic data while uncertainty is naturally present in applications. The definitions of SSDPs and CCSDPs in [1,2] were formulated with the expectation that they would enhance optimization modeling in applications that lead to semidefinite programs by providing ways to handle uncertainty in data. In this paper, we present results of our attempts to create SSDP and CCSDP models in four such applications. Our results are promising and we hope that the applications presented in this paper would encourage researchers to consider SSDP and CCSDP as new paradigms for stochastic optimization when they formulate optimization models.
Axioms of causal relevance

Abstract This paper develops axioms and formal semantics for statements of the form “X is causally irrelevant to Y in context Z”, which we interpret to mean “Changing X will not affect Y once Z is held constant”. The axiomization of causal irrelevance is contrasted with the axiomization of informational irrelevance, as in “Finding X will not alter our belief in Y, once we know Z”. Two versions of causal irrelevance are analyzed: probabilistic and deterministic. We show that, unless stability is assumed, the probabilistic definition yields a very loose structure that is governed by just two trivial axioms. Under the stability assumption, probabilistic causal irrelevance is isomorphic to path interception in cyclic graphs. Under the deterministic definition, causal irrelevance complies with all of the axioms of path interception in cyclic graphs except transitivity. We compare our formalism to that of Lewis (1973) and offer a graphical method of proving theorems about causal relevance.
Location of the nonthermal optical emission from jets in AGN

Abstract As part of an approved key science project for the Space Interferometry Mission (SIM), we plan to measure the position offsets between red and blue optical emission from a sample of Active Galactic Nuclei. By using differential measurements of the fringe phase between different color bands, we expect to be able to detect color-dependent astrometric offsets at the micro-arcsecond level. The blue optical continuum is dominated by thermal emission from the inner accretion disk (the source of the Big Blue Bump) in many quasar spectra. The red optical continuum is expected to be dominated by power-law non-thermal emission from the relativistic jet or from a hot corona surrounding the inner accretion disk. Our measurements of position offsets between blue and red light will allow us to determine the location of non-thermal optical emission with respect to the thermal emission from the inner accretion disk. We will also be able to monitor the astrometric stability of the optical emission centroids.
Conditional phase-shifter in refractive index enhancement scheme

We propose a conditional phase-shifter between two weak laser beams in an alkali vapor. We begin by enhancing the refractive index of a weak, far-detuned probe beam while maintaining vanishing absorption. The enhancement is a result of interfering an absorptive and an amplifying Raman resonance in a four-level atomic system. Then, a conditional switching beam ac stark shifts the narrow Raman resonances, modifying the phase accumulation experienced by the probe beam. We find that the scheme works with acceptable fidelity at the tens of photons level, and that the energy requirement can be reduced further at the expense of noise.
Popliteal artery occlusion by a popliteal (Baker's) cyst.

This short report describes the unusual finding of a popliteal cyst causing popliteal artery thrombosis and notes the differences between this condition and cystic adventitial disease of the popliteal artery. Non-atheromatous occlusion of the popliteal artery is an uncommon but important cause of ischaemia of the lower limb. It usually occurs in an age range younger than that of degenerative arterial disease, in otherwise healthy men. The most frequent causes are popliteal entrapment syndrome and cystic adventitial disease of the popliteal artery. 1,2 We report a case of popliteal artery thrombosis as a result of pressure from a true popliteal cyst.
Improvement of the crystallizability and expression of an RNA crystallization chaperone

Crystallizing RNA has been an imperative and challenging task in the world of RNA research. Assistive methods such as chaperone-assisted RNA crystallography (CARC), employing monoclonal antibody fragments (Fabs) as crystallization chaperones have enabled us to obtain RNA crystal structures by forming crystal contacts and providing initial phasing information. Despite the early successes, the crystallization of large RNA–Fab complex remains a challenge in practice. The possible reason for this difficulty is that the Fab scaffold has not been optimized for crystallization in complex with RNA. Here, we have used the surface entropy reduction (SER) technique for the optimization of ΔC209 P4–P6/Fab2 model system. Protruding lysine and glutamate residues were mutated to a set of alanines or serines to construct Fab2SMA or Fab2SMS. Expression with the shake flask approach was optimized to allow large scale production for crystallization. Crystal screening shows that significantly higher crystal-forming ratio was observed for the mutant complexes. As the chosen SER residues are far away from the CDR regions of the Fab, the same set of mutations can now be directly applied to other Fabs binding to a variety of ribozymes and riboswitches to improve the crystallizability of Fab–RNA complex.
The politics of phosphorus-32: A cold war fable based on fact

ABSTRACT In July 1949, and again in January 1950 the U.S. Atomic Energy Commission shipped useful amounts of the short-lived isotope phosphorus-32 to a sanatorium in Trieste, Italy. They were used to treat a patient who had a particularly malignant kind of brain tumor. This distribution of isotopes abroad for medical and research purposes was hotly contested by Commissioner Lewis Strauss, and led to a bruising confrontation between him and J. Robert Oppenheimer. This paper describes the debates surrounding the foreign isotope program inside the Commission and in the U.S. Congress. In parallel, it presents an imagined, but factually-based story of the impact of isotope therapy on the patient and his doctor in Trieste, a city on the Italian-Yugoslavian border that was at the heart of the cold war struggle for influence between the U.S. and the USSR. It weaves together the history of science, institutional history, diplomatic history, and cultural history into a fable that draws attention to the importance of the peaceful atom for winning hearts and minds for the West. The polemics surrounding the distribution of isotopes to foreign countries may have irreversibly soured relationships between Oppenheimer and Strauss, and played into the scientist9s loss of his security clearance. But, as those who supported the program argued, it was an important instrument for projecting a positive image of America among a scientifc elite abroad, and for consolidating its alliance with friendly nations in the early years of the cold war——or so the fable goes.
Performance and leaching analysis of a novel coal sludge-based backfill material

In this article, an innovative backfill material is introduced as a green material largely utilizing two major coal mining waste: coal refuse and coal sludge. Coal refuse is rock-like solid waste, comparatively, raw coal sludge is slurry. A smart recipe design of backfill material was introduced, which contains only 1 % of cement and the rest 99 % of raw material is from industry waste. The backfill material at 75 % pulp density shows excellent performance such as high unconfined compressive strength, great flowability, and low bleeding rate. Also, the article discusses the morphology change of the backfill harden body during different curing ages, the observation through SEM–EDS illustrates the distinguished morphological characterization of the needle-like ettringite and amorphous gel. Furthermore, TCLP results indicate that this designed backfill material is environmentally acceptable and none of the heavy metal leaching has over the limitation by US Environmental Protection Agency (EPA).
Macrocyclic depolymerization of arylene-ethynylene copolymers: a dynamic combinatorial method

A dynamic combinatorial approach for the synthesis of arylene ethynylene macrocycles (AEMs) from linear polymers is described. By using readily available carbazolyl-ethynylene copolymers as starting materials we obtained a number of novel macrocycles that would be difficult to prepare by traditional methods.