cssi/SciSciGPT-SciSciNet huggingface dataset:
Intussusception in adults: institutional review.

Abstract Background: Intestinal intussusception in the adult is a rare entity that differs greatly in etiology from its pediatric counterpart. Controversy remains regarding the optimal management of this problem in the adult patient. The purpose of this study was to determine the cause(s) of intussusception and to determine the role of intestinal reduction in the management of intussusception in adults. Study Design: A retrospective review performed at The Mount Sinai Medical Center identified 27 patients, 16 years and older, with a diagnosis of intestinal intussusception. Data related to presentation, diagnosis, treatment, and pathology were analyzed. Results: There were 13 males and 14 females. The median age of the group was 52 years with a range of 16 to 90 years. Abdominal pain was the most common presenting complaint. A preoperative diagnosis was suspected in 11 of 27 patients (40%). There were 22 small bowel lesions and 5 colonic lesions. A pathologic cause was identified in 85% of patients with 8 of 22 (36%) small bowel and 4 of 5 (80%) of large bowel lesions being malignant. All small bowel cancers represented metastatic disease and all large bowel malignancies were primary adenocarcinomas. The median age of patients with malignant disease was 60 years; it was 44 years for those with benign disease. Operative treatment consisted of resection alone in 58% of patients and resection after reduction in 42%. Three patients were treated nonoperatively. Conclusions: Our data support a selective approach to the operative treatment of intussusception in adults. Colonic lesions should not be reduced before resection because they most likely represent a primary adenocarcinoma. Small bowel intussusception should be reduced only in patients in whom a benign diagnosis has been made preoperatively or in patients in whom resection may result in short gut syndrome.
IT Portfolio & IT Savvy (Working Title)

Managing the IT Portfolio (Update Circa 2003) (with Sinan Aral), Vol. III, No. 1C, March 2003. Introduces the MIT CISR IT Portfolio framework with four IT asset classes and provides benchmarks for 2001 and 1993-97. "Managing the IT Portfolio: Returns from the Different IT Asset Classes" (with Sinan Aral), Vol. IV, No. 1A, March 2004. Provides firm performance returns for investments in each of the four IT asset classes. "IT Savvy Pays Off" (with Sinan Aral), Vol. IV, No. 3B, October 2004. Demonstrated the extra returns to the bottom line from IT investment in firms with high IT Savvy (a set of interlocking IT practices and competencies). "IT Savvy: Achieving Industry Leading Returns from Your IT Portfolio" (with Sinan Aral), Vol V, No. 2A, July 2005. Case studies on companies with high and low IT Savvy plus suggestions for maximizing the business value of IT investments. "Managing the IT Portfolio (Update Circa 2005): Where Did the Infrastructure Go?" (with Anne Johnson), Vol V. No. 3A, December 2005. IT Portfolio benchmarks for 2005 and 2001 - demonstrating a significant drop in IT infrastructure. "How IT Savvy is Your Enterprise? Self Assessment and Benchmarking" (with Sinan Aral), Vol. VI, No. 1A, March 2006. A self assessment for IT Savvy with benchmarks.
The Simple, the Complicated, and the Complex: Educational Reform Through the Lens of Complexity Theory

This paper explores the nature of complexity theory and its applications for educational reform. It briefly explains the history of complexity theory and identifies the key concepts of complex adaptive systems, and then moves on to define the differences between simple, complicated, and complex approaches to educational reform. Special attention is given to work currently underway in the fields of healthcare, emergency management and ecology that draws on complexity theory to build more resilient and robust response systems capable of adapting to changing needs and of identifying key pressure points in the system. Finally, this paper presents several examples of educational reform programmes undertaken worldwide that have implemented complexity theory principles to achieve positive results. It also recommends involving multiple stakeholders across the different levels of governance structure, increasing lateral knowledge-sharing between schools and districts, and transforming policy interventions to bring greater flexibility to the reform process. This move toward feedback-driven adaptive reform allows for better targeting of programmes to specific contexts and may prove a key way forward for educational policymakers.
Combined treatment with a nonselective nitric oxide synthase inhibitor (l-NMMA) and indomethacin increases ductus constriction in extremely premature newborns.

Studies in premature animals suggest that 1) prolonged tight constriction of the ductus arteriosus is necessary for permanent anatomic closure and 2) endogenous nitric oxide (NO) and prostaglandins both play a role in ductus patency. We hypothesized that combination therapy with an NO synthase (NOS) inhibitor [NG-monomethyl-l-arginine (l-NMMA)] and indomethacin would produce tighter ductus constriction than indomethacin alone. Therefore, we conducted a phase I and II study of combined treatment with indomethacin and l-NMMA in newborns born at <28 weeks' gestation who had persistent ductus flow by Doppler after an initial three-dose prophylactic indomethacin course (0.2, 0.1, 0.1 mg/kg/24 h). Twelve infants were treated with the combined treatment protocol [three additional indomethacin doses (0.1 mg/kg/24 h) plus a 72-hour l-NMMA infusion]. Thirty-eight newborns received three additional indomethacin doses (without l-NMMA) and served as a comparison group. Ninety-two percent (11/12) of the combined treatment group had tight ductus constriction with elimination of Doppler flow. In contrast, only 42% (16/38) of the comparison group had a similar degree of constriction. l-NMMA infusions were limited in dose and duration by acute side effects. Doses of 10–20 mg/kg/h increased serum creatinine and systemic blood pressure. At 5 mg/kg/h, serum creatinine was stable but systemic hypertension still limited l-NMMA dose. We conclude that combined inhibition of NO and prostaglandin synthesis increased the degree of ductus constriction in newborns born at <28 weeks' gestation. However, the combined administration of l-NMMA and indomethacin was limited by acute side effects in this treatment protocol.
Computer-aided pipeline operation using genetic algorithms and rule learning. PART I: Genetic algorithms in pipeline optimization

In this two-paper series, techniques connected with artificial intelligence and genetics are applied to achieve computer-based control of gas pipeline systems. In this, the first paper, genetic algorithms are developed and applied to the solution of two classical pipeline optimization problems, the steady serial line problem, and the single transient line problem. Simply stated, genetic algorithms are canonical search procedures based on the mechanics of natural genetics. They combine a Darwinian survival of the fittest with a structured, yet randomized, information exchange between artificial chromosomes (strings). Despite their reliance on stochastic processes, genetic algorithms are no simple random walk; they carefully and efficiently exploit historic information to guide future trials. In the two pipeline problems, a simple three-operator genetic algorithm consisting of reproduction, crossover, and mutation finds near-optimal performance quickly. In, the steady serial problem, near-optimal performance is found after searching less than 1100 of 1.1(1012) alternatives. Similarly, efficient performance is demonstrated in the transient problem. Genetic algorithms are ready for application to more complex engineering optimization problems. They also can serve as a searning mechanism in a larger rule learning procedure. This application is discussed in the sequal.
The supremum of a process with stationary independent and symmetric increments

Let Xt, t ⩾ 0, be a process with stationary independent and symmetric increments. If the tail of the Levy spectral measure in the representation of the characteristic function is of regular variation of index −α, for some 0 u) ∼ P(Xt, > u), for u → ∞,for each t > 0.
Effects of food deprivation on free-operant avoidance.

2 marmoset monkeys were exposed to a schedule of continuous avoidance on which each response postponed for 30-sec. shock which otherwise occurred every 5 sec. Once stable, efficient avoidance developed, each animal was food-deprived to 80% of his free-feeding weight. Sessions continued until the behavior again stabilized, after which the animal was returned to a free-feeding schedule. Eight such weight changes showed initial increases in response rate and decreases in shocks taken, irrespective of body weight (perhaps extended acquisition). In later sessions, avoidance efficiency was clearly positively correlated with body weight. Thus, deprivation had a deleterious effect on established avoidance, producing reduced response rate and increased shock rate.
Gradient polymer-fullerene photovoltaic composites induced by thermally-controlled interdiffusion

Efficient polymer-fullerene photovoltaic devices require close proximity of the two components to ensure photoexcited electron transfer from the semiconducting polymer to the fullerene acceptor. We describe studies in which a bilayer system consisting of spin-cast 2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene copolymer (MEH-PPV) and sublimed C60 is heated above the MEH-PPV glass transition temperature in an inert environment, inducing an interdiffusion of the polymer and the fullerene layers. With this process, a controlled, bulk gradient heterojunction is created bringing the fullerene molecules within the exciton diffusion radius of the MEH-PPV throughout the film to achieve highly efficient charge separation [1]. The interdiffused devices show a dramatic decrease in photoluminescence and concomitant order-of-magnitude increase in short circuit currents, demonstrating the improved interface. Figure 1 shows the spectral photoresponsivity (from bottom to top) of devices consisting of an MEH-PPV single layer, MEH-PPV/C60 bilayer, MEH-PPV/C60 bilayer interdiffused at 150 °C, and MEH-PPV/C60 bilayer interdiffused at 250 °C. The figure also shows that a valley in the spectral photoresponsivity of the MEH-PPV/C60 bilayer system, ascribed to the short optical penetration depth at the peak of the MEH-PPV absorbance, is eliminated following the interdiffusion process. Detailed studies of the effects of the initial MEH-PPV and C60 thicknesses and the time-temperature profile of the heat treatment on device efficiency will be presented. Furthermore, transmission electron microscopy and Auger spectroscopy studies of the nanoscale film composition have demonstrated that C60 intrdiffuses into the MEH-PPV polymer as rather large aggregates, most likely as a result of the low miscibility of the two materials. Further enhancements in the photovoltaic efficiency have been achieved with a photoexciited electron donor-acceptor pair that is more miscible, providing a smoother gradient cocentration profile.
Identification of a developmentally regulated keratan sulfate proteoglycan that inhibits cell adhesion and neurite outgrowth

Monoclonal antibodies have been used to identify a 320 kd keratan sulfate proteoglycan that is primarily expressed in the embryonic chick nervous system. Immunohistochemical localization of the proteoglycan shows that it is expressed by putative midline barrier structures in the developing chick central nervous system. When added to laminin or neural cell adhesion molecule that has been adsorbed onto nitrocellulose-coated dishes, the proteoglycan abolishes cell attachment and neurite outgrowth on these adhesive substrata. This effect can be reversed by keratanase treatment and incubation with a monoclonal antibody that recognizes the keratan sulfate chains of the proteoglycan. These data suggest that this neural keratan sulfate proteoglycan plays an important role in the modulation of neuronal cell adhesion during embryonic brain development.
Regulation of ovarian follicular development: A review of microscopic studies

Follicular development in the mammalian ovary is a complex process regulated by an orchestrated action of the pituitary gonadotropins, e.g., follicle stimulating hormone (FSH) and luteinizing hormone (LH), and local ovarian factors, such as peptide growth factors and steroids. The mechanism of endocrine/paracrine/autocrine regulation of folliculogenesis (i.e., cell proliferation and functions) has been addressed largely by biochemical means. However, the availability of immunological and molecular tools now enables us to undertake critical microscopic studies revealing the ovarian cell-type specific synthesis and/or accumulation of many of these local peptide modulators, their roles in the proliferation and differentiation of follicular cells, and their regulation by gonadotropins and local factors. The objective of this review is to provide a comprehensive yet complete picture of the endocrine/autocrine regulation of mammalian folliculogenesis as revealed by microscopic studies. Efforts have been made to include adequate research information relevant to update our understanding of the process of follicular development; however, to maintain the brevity, many equally important studies could not be included. This review confirms that FSH and LH are still the primary stimuli for follicular development. However, it is clear that the actions of these hormones at the cell level involve a host of peptide factors which are produced locally by different follicular cell types and which are powerful modulators of gonadotropin actions. The temporal and spatial expression of the genes of these modulators, the synthesis of active factors, their interactions, and the dynamics of their receptors on the follicular cell surface may be the ultimate determinants of cellular events which are crucial to coordinated growth and differentiation of follicular cells leading to folliculogenesis and ovulation.
The ordered array of perivascular macrophages is disrupted by IL-1-induced inflammation in the rabbit retina.

In this study we have shown that an antibody to CD18 identified a population of cells in the rabbit retina that resembled the perivascular macrophage found in other regions of the central nervous system. In the normal retina these cells possessed a ramified morphology and presented in an ordered array on the vitreal surface in association with the epiretinal vessels. Approximately 50% of the perivascular macrophages constitutively expressed MHC class II. In response to interleukin-1β (IL-1β)-induced inflammation, these cells became activated, as evidenced by a change from a ramified to an ameboid morphology and increased expression of MHC class II, and migrated away from the vessels. These changes were first detected around 3 h post-intraocular challenge coincident with the onset of inflammation. At the peak of the inflammatory response (∼24 h post-challenge), many activated perivascular macrophages were no longer associated with the vessels and formed long “cords” of MHC class II+ cells associated with underlying deposits of fibrin. In eyes challenged with heat-inactivated IL-1, no change in the morphology or distribution of the perivascular macrophage was noted. At 3 weeks post-challenge with IL-1, the number and distribution of the perivascular macrophages were restored to baseline values, although with a reduced cell size. Since these changes closely resemble those that occur in non-lymphoid dendritic cells in the skin, heart, and/or kidney following activation with cytokines or bacterial products, the results suggest that the perivascular macrophage represents the dendritic cell of the retina and may thus play an important role in immune surveillance in the eye and maintenance of the blood-retina barrier. © 1996 Wiley-Liss, Inc.
Ethyl pyruvate preserves cardiac function and attenuates oxidative injury after prolonged myocardial ischemia.

Abstract Objective Myocardial injury and dysfunction following ischemia are mediated in part by reactive oxygen species. Pyruvate, a key glycolytic intermediary, is an effective free radical scavenger but unfortunately is limited by aqueous instability. The ester derivative, ethyl pyruvate, is stable in solution and should function as an antioxidant and energy precursor. This study sought to evaluate ethyl pyruvate as a myocardial protective agent in a rat model of ischemia-reperfusion injury. Methods Rats underwent 30-minute ischemia and 30-minute reperfusion of the left anterior descending coronary artery territory. Immediately prior to both ischemia and reperfusion, animals received an intravenous bolus of either ethyl pyruvate (n = 26) or vehicle control (n = 26). Myocardial high-energy phosphate levels were determined by adenosine triphosphate assay, oxidative injury was measured by lipid peroxidation assay, infarct size was quantified by triphenyltetrazolium chloride staining, and cardiac function was assessed in vivo. Results Ethyl pyruvate administration significantly increased myocardial adenosine triphosphate levels compared with control (87.6 ± 29.2 nmol/g vs 10.0 ± 2.4 nmol/g, P = .03). In ischemic myocardium, ethyl pyruvate reduced oxidative injury compared with control (63.8 ± 3.3 nmol/g vs 89.5 ± 3.0 nmol/g, P P = .005). Ethyl pyruvate improved myocardial function compared with control (maximum pressure: 86.6 ± 2.9 mm Hg vs 73.5 ± 2.5 mm Hg, P P = .005; maximal rate of ventricular systolic volume ejection: 3097 ± 479 μL/s vs 2120 ± 287 μL/s, P = .04; ejection fraction: 41.9% ± 3.8% vs 31.4% ± 4.1%, P = .03; cardiac output: 26.7 ± 0.9 mL/min vs 22.7 ± 1.3 mL/min, P = .01; and end-systolic pressure-volume relationship slope: 1.09 ± 0.22 vs 0.59 ± 0.2, P = .02). Conclusions In this study of myocardial ischemia-reperfusion injury, ethyl pyruvate enhanced myocardial adenosine triphosphate levels, attenuated myocardial oxidative injury, decreased infarct size, and preserved cardiac function.
Compositional nonuniformities and strain relaxation at misoriented In x Ga (1-x) As/GaAs interfaces

Compositional nonuniforimities and misfit dislocations are observed near misoriented In0.2Ga0.8As/GaAs interfaces. The compositional nonuniformities results from In interdiffusion at the interface over a distance of 3 nm and formation of InAs platelet precipitates. The misfit dislocations are of pure edge and 60° types. The core of pure edge misfit dislocations generally consists of two 60° dislocations separated by approximately 2.5 nm. One of these 60° dislocations is usually split into partials and decorated by platelets of InAs. The interface and surface morphologies are strongly influenced by the substrate tilt away from exact [001] crystallographic orientation.
Morphology of the lingual apparatus of the domestic chicken, Gallus gallus, with special attention to the structure of the fasciae.

A detailed redescription of the mechanically interacting structural elements of the lingual apparatus of the domestic chicken, Gallus gallus, revealed the functional and constructional role of organized connective tissue (i.e., ligaments and fasciae) as structural elements that ensure the proper biomechanical interactions among the various structures within the lingual apparatus (e.g., cartilaginous and bony skeletal elements, muscles, salivary glands, epithelial structures). Fasciae, together with extrinsic muscles, also connect the lingual apparatus to the other components of the feeding apparatus, such as the skull, jaw apparatus, and larynx. For example, the hyoid apparatus is attached to the skull by a sheath-like fascia (F. vaginalis), the internal structure of which is described here for the first time. Thus, the hyoid suspension in birds differs fundamentally from that in mammals. This study is the first to examine all biomechanically functioning structural elements that are part of the galliform lingual apparatus in a systematic and comprehensive manner. It also provides a set of novel characters that may be useful for future comparative studies in evolutionary and functional morphology.
How well do physicians recognize melanoma and other problem lesions

The alarming increase in the incidence of cutaneous malignant melanoma in the United States emphasizes the importance of its early detection and treatment. Early detection requires accurate clinical recognition of both malignant and precancerous skin lesions (dysplastic nevi). This study presents data on dermatologists' and nondermatologists' ability to diagnose skin lesions. A total of 105 nondermatologist physicians, from first-year residents to practicing physicians, and forty-eight dermatologists were asked to identify color slides or photographs of eleven cutaneous lesions, including malignant melanomas, dysplastic nevi, and innocuous lesions such as seborrheic keratoses and common moles. Diagnosis of cutaneous lesions was generally inaccurate among nondermatologists. Only 38% correctly identified four or more of the six melanomas as melanoma of any type, and 58% were unable to diagnose dysplastic nevi. Only 17% categorized their relevant training as excellent or good. Improved training in the diagnosis of skin lesions for practicing physicians and house staff is required if mortality from malignant melanoma is to be decreased in the United States.
"I've fallen and i can't get up," a basic primer for caregivers to understand falls in persons with dementia, Alzheimer's disease, and cognitive impairment

This article seeks to demystify the complexity of what constitutes dementia, Alzheimer's disease, and cognitive impairment as it relates to identifying the basic contexts of these diseases in relationship with falls and fall prevention. It further will identify the new changes in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5) that replaces the term dementia and provides the new diagnostic framework for major and mild neurocognitive functioning. This article additionally provides some practical strategies for caregivers to equip themselves to understand some of the difficulties and challenges that they face when dealing with loved ones or patients who become afflicted by these diseases. Language: en
Predicting Job‐Related Expectancies and Affective Reactions to Employees With Disabilities From Previous Work Experience1

The relationship between the quality of previous work experience with a coworker who was disabled, job-related expectancies of employees with disabilities, and affective reactions to employees with disabilities was investigated. Data from individuals who had worked with a coworker who was disabled were collected via an Internet-based survey. The quality of previous experience with coworkers with disabilities predicted job-related expectancies of employees with disabilities and affective reactions to employees with disabilities. More positive work experiences were associated with more positive expectancies and affective reactions. The relationship between previous experience and affective reactions was mediated by job-related expectancies. Perceptions of increased job difficulty that were attributed to a coworker who was disabled predicted less positive job-related expectancies and affective reactions.
Spontaneous improvement in pancreatic function in chronic pancreatitis.

Chronic pancreatitis is a disease with varying etiologic factors. It is relatively easy to diagnose in its later stages, but notoriously difficult early in its course. Treatment is often unsatisfactory. The clinical features of chronic pancreatitis are abdominal pain and the consequences of destruction of the exocrine and endocrine pancreas--steatorrhea and diabetes mellitus. Pain is less common in patients with chronic calcific pancreatitis than in chronic noncalcific pancreatitis. It may be absent even in patients continuing to abuse alcohol (1). Recently, a report appeared indicating that treatment with oral pancreatic extracts can relieve the pain of some patients with chronic pancreatitis (2). This has been attributed to a negative feedback mechanism in which trypsin in the duodenum inhibits the secretion of chymotrypsin by decreasing the release of cholecystokinin (3). The steatorrhea of chronic pancreatitis can usually be controlled by adequate replacement treatment with pancreatic extracts (4). However, fecal fat excretion is rarely reduced to normal levels. Inactivation of lipase by acid in the duodenum in the face of reduced duodenal bicarbonate secretion may account for failure of substitution therapy in some patients (5). In this issue of the journal Begley and RobertsThomas report three patients with chronic pancreatitis confirmed by ductal changes seen on ERCP who appear to have experienced a spontaneous reduction in the fecal excretion of fat; from 60 to 6 and 11 g/day in two patients and from 9 g while on substitution therapy to 3 g/day off treatment in the third. The duodenal bicarbonate concentration after secretin increased slightly as the steatorrhea decreased in one patient. The period of observation extended over 3, 22, and 27 years in the three patients. Diabetes was present in two patients, and the glucose tolerance test was mildly abnormal in
Polyphenol control of nitrogen release from pine litter

THE importance of dissolved organic nitrogen in ecosystem nutrient fluxes and plant nutrition is only beginning to be appreciated1,2. Here we report that the polyphenol concentration of decomposing Pinus muricata litter controls the proportion of nitrogen released in dissolved organic forms relative to mineral forms (NH+4 + NO-3). We have previously shown that concentrations of polyphen-ols in P. muricata foliage vary along an extreme soil acidity/ fertility gradient3. Apparently this feedback to soil conditions controls the dominant form in which litter nitrogen is mobilized, facilitating nitrogen recovery through pine-mycorrhizal associations, minimizing nitrogen availability to competing organisms, and attenuating nitrogen losses from leaching and denitrification. Polyphenol control of nitrogen dynamics helps explain the convergent evolution of tannin-rich plant communities on highly leached soils.
The effects of six bases of power upon compliance, identification, and internalization

The links between Raven ’s (1965) and Kelman ’s (1958) models of influence were assessed in a questionnaire study. Coercive, informational, and reward power were rated as especially likely to elicit compliance; coercive power was most likely to elicit negative identification with the influence transmitter; finally, informational and coercive power were rated as most likely to elicit internalization.
Balancing the needs of children and adults in the design of technology for children

In the design of technology for children, many products hope to encourage ideal behavior. Goals or desired outcomes for children-oriented products, such as learning, exploration or self-expression, are often set by adults (e.g. parents, guardians, teachers). These adult goals are often considered alongside the goals and interests of children, but what happens when these are conflicting? It is common for technology creators to have to make choices that support or prioritize one set of goals over the other.In this workshop, we will be discussing real world case studies, as well as theoretical approaches used by researchers, designers, and academics to design technology for children between the ages of 5 and 14. The expected outcome of the workshop will be a set of principles to consider when balancing the needs of children and adults in the design of technology for children.
Analysis of photon emission from 50--350-keV proton impact on H 2 O

We have measured photon emission cross sections from neutral fragments produced by collisions of 50--350 keV protons with ${\mathrm{H}}_{2}$O molecules. Balmer $\ensuremath{\alpha}\ensuremath{-}\ensuremath{\delta}$ emissions from both the target and projectile were recorded. We also analyzed $A {}^{2}{\ensuremath{\Sigma}}^{+}\ensuremath{-}X {}^{2}\ensuremath{\Pi}$ (0,0) and (1,0) emission from the excited OH fragment produced during target dissociation. Trends in the cross sections revealed two key properties of the collision process: (1) The Bethe theory accurately describes target emission from both H and OH fragments and (2) the ratio of any two Balmer emission cross sections for both the target and projectile can be approximated by simple functions of the respective optical oscillator strengths. Finally, we provide the Bethe fit parameters necessary to calculate the target emission cross sections at all nonrelativistic impact energies.
Geographical information systems at Princeton University: evaluation and exploration of a new library service

Reviews some of the popular Geographical Information Systems (GIS) and related digital data sources. Discusses the results of interviews with Princeton University Library patrons and others involved with GIS within the context of a potential GIS service. Develops a proposal for a GIS service for Princeton University with emphasis on the need for training and creating the digital collections that will be most relevant for the University.
Risk-specific nosocomial infection rates

Because nosocomial infection rates vary by hospital area and service, most infection control programs calculate area-specific rates to augment the reporting of their hospital-wide data. Rate development is often limited by the availability of appropriate specific denominator data to support important comparisons. Our university hospital reports a 20 month experience in which numerator data was collected as per the National Nosocomial Infections Surveillance System criteria for hospital-wide, high-risk nursery and ICU surveillance. These data were then combined with data in our hospital's patient-specific denominator file. This has enabled the development of risk-specific infection rates based on the analytic control of important variables available in both the numerator and denominator files. We found rate differences that were length of stay cohort specific, hospital day specific, age specific, birthweight specific, and survival cohort specific when examining our data by both the cumulative incidence and incidence density methods.
Magnetic resonance imaging and transvaginal ultrasound for determining fibroid burden: implications for research and clinical care

Objectives To compare magnetic resonance and ultrasound imaging for uterine fibroid measurement. Study Design Eighteen women undergoing hysterectomy for symptomatic fibroids underwent preoperative pelvic ultrasound and magnetic resonance imaging. Resected fibroids were correlated with the images. Weighted κ agreement statistics and Spearman correlations for patient characteristics were calculated. Results Magnetic resonance imaging identified 121 of 151 pathologically confirmed fibroids, yielding 91% positive predictive value (95% confidence interval [CI], 85-95) and 80% sensitivity (95% CI, 73-86). Positive predictive value and sensitivity for ultrasound were 97% (95% CI, 89-100) and 40% (95% CI, 32-48), respectively. Mean diameter-equivalent discrepancies between imaging and pathologic measurements were 0.51 ± 0.68 cm for magnetic resonance imaging and 0.76 ± 0.88 cm for ultrasound. κ statistics comparing imaging to pathology showed better agreement for magnetic resonance than ultrasound (κ = 0.60 vs 0.36). The number of fibroids detected by magnetic resonance imaging predicted measurement errors (r = 0.76; P = .0002). Conclusion Superior sensitivity and minimal measurement discrepancies suggest magnetic resonance imaging may be preferentially used for fibroid assessment in clinical research.
X-ray absorption near-edge spectroscopy in bioinorganic chemistry: Application to M-O2 systems.

Metal K-edge X-ray absorption spectroscopy (XAS) has been extensively applied to bioinorganic chemistry to obtain geometric structure information on metalloprotein and biomimetic model complex active sites by analyzing the higher energy extended X-ray absorption fine structure (EXAFS) region of the spectrum. In recent years, focus has been on developing methodologies to interpret the lower energy K-pre-edge and rising-edge regions (XANES) and using it for electronic structure determination in complex bioinorganic systems. In this review, the evolution and progress of 3d-transition metal K-pre-edge and rising-edge methodology development is presented with particular focus on applications to bioinorganic systems. Applications to biomimetic transition metal–O2 intermediates (M = Fe, Co, Ni and Cu) are reviewed, which demonstrate the power of the method as an electronic structure determination technique and its impact in understanding the role of supporting ligands in tuning the electronic configuration of transition metal–O2 systems.
Low night temperature effect on photosynthate translocation of two C4 grasses.

Translocation of assimilates in plants of Echinochloa crus-galli, from Quebec and Mississippi, and of Eleusine indica from Mississippi was monitored, before and after night chilling, using radioactive tracing with the short-life isotope 11C. Plants were grown at 28°/22°C (day/night temperatures) under either 350 or 675 μl·l-1 CO2. Low night temperature reduced translocation mainly by increasing the turn-over times of the export pool. E. crus-galli plants from Mississippi were the most susceptible to chilling; translocation being completely inhibited by exposure for one night to 7°C at 350 μl·l-1 CO2. Overall, plants from Quebec were the most tolerant to chilling-stress. For plants of all three populations, growth under CO2 enrichment resulted in higher 11C activity in the leaf phloem. High CO2 concentrations also seemed to buffer the transport system against chilling injuries.
Activation of cardiac ryanodine receptors by the calcium channel agonist FPL-64176

We investigated the possibility that the Ca2+ channel agonist FPL-64176 (FPL) might also activate the cardiac sarcoplasmic reticulum (SR) Ca2+ release channel ryanodine receptor (RyR). The effects ...
Nucleotide transport in African trypanosomes

Abstract 1. 1. The African trypanosomes, T. brucei and T. rhodesiense appear capable of transporting the nucleotides—ATP, ADP, AMP and cyclic-AMP. 2. 2. Of the four nucleotides tested AMP is transported at the highest rate. It, as well as cyclic-AMP appear to have regulatory properties on the parasite's metabolism. The activity of phosphofructokinase is altered by incubation of the parasites in solutions containing the nucleotides. 3. 3. The data is discussed with respect to the host's contribution of factors which regulate the parasite's metabolism.
Combat trauma training for current casualty care.

Abstract : The US Army's health service support in combat operations is organized into echelons of care from levels I to IV, with level or echelon V care located outside the combat theater, and usually consisting of Department of Defense (DOD) or Department of Veterans Affairs (VA) hospitals. These levels of care denote the available medical capabilities of each location. Patient evacuation usually occurs from one level to the next as necessary. Level I is unit-level health care and the first care a soldier receives after injury. It includes treatment and evacuation from the point of injury or illness to the unit's aid station. Further evacuation proceeds through Level IIa (forward surgical team), Level III (combat support hospital), Level IV (field or general hospital) and Level V.
The effects of forced sexual intercourse on white female adolescents

In the 1987 National Survey of Children the question was asked: "Was there ever a time when you were forced to have sex against your will, or were you raped?" Among White females, aged 18-22, those who answered yes (n = 41) and no (n = 400) were compared on a number of social-psychological and sexual variables that might be thought of as outcomes affected by having had coercive sexual experience(s). Those who reported being forced to have sexual intercourse, compared to those who did not, had more permissive attitudes about 16-17-year-olds having intercourse and a younger age of first voluntary sexual intercourse themselves. They also had lower internal locus of control and higher depression scores, and they needed and received more psychological help than those not reporting forced sexual intercourse. Dividing the forced sexual intercourse group (FSI) into those reporting FSI before versus after their first date, and those whose FSI was before versus after age 12, yielded essentially the same findings. Even in the presence of multivariate control variables. FSI experience remained a significant predictor of age at first voluntary sexual intercourse, locus of control, depression, and perceived need for psychological help. These analyses of national survey data support the clinical perspective that forced sexual intercourse causes or exacerbates various sexual and psychological problems.
Field-Effect Transistors Based on Single Semiconducting Oxide Nanobelts

We have fabricated field-effect transistors (FETs) based on single SnO2 and ZnO nanobelts of thicknesses between 10 and 30 nm. Switching ratios as large as 6 orders of magnitude and conductivities as high as 15 (Ω cm)-1 are observed. Annealing SnO2 nanobelt FETs in an oxygen-deficient atmosphere produces a negative shift in gate threshold voltage, indicating doping by the generation of surface oxygen vacancies. This treatment provides an effective way of tuning the electrical performance of the nanobelt devices. The ability of SnO2 FETs to act as gas sensors is also demonstrated. SnO2 FETs with lengths of about 500 nm or less show an anomalous behavior where the conductance cannot be modulated by the gate. ZnO nanobelt FETs are sensitive to ultraviolet light. Both photogeneration of electron−hole pairs and doping by UV induced surface desorption contribute to the conductivity.
EXPERIMENTAL SYPHILIS IN THE RABBIT : I. PRIMARY INFECTION IN THE TESTICLE.

A study was made of the infections produced in rabbits inoculated in the testicles with two strains of Treponema pallidum which had been carried in rabbits for several years. Infection resulted in all instances; the incubation period varied as a rule between 2 and 6 weeks and under properly chosen conditions could be reduced to approximately 3 weeks or less. The resulting infection pursued a typically cyclic or relapsing course which affected both the spirochetes and the associated lesions in the testicle. The spirochetes in the local lesions exhibited periodic changes less marked and less regular but identical in character with the changes which occur in the blood in cases of relapsing fever. The lesions in the testicle also showed periods of active development and quiescence or regression which followed closely upon the changes exhibited by the spirochetes. The specific reaction in the testicle showed considerable variation in the speed and sharpness with which successive phenomena occurred as well as in the character and extent of the processes themselves. These reactions were of two fundamental types. In one group of animals, the reaction was characterized by an intense cycle of acute exudation and infiltration with a lesser degree of proliferation, followed by crisis and subsequent recurrence of secondary cycles of proliferative reaction of a minor degree. In the other group of animals, the reaction was more chronic in character and consisted largely of infiltration and proliferation. The progress of the reaction was more gradual, and sharp alterations in its course were absent. The infection progressed by a succession of stages with slight and irregular remissions. In a third group of animals, the reaction was subacute, combining at the same time the processes of exudation, infiltration, and proliferation. The first cycle of reaction was fairly acute and terminated in a definite crisis with moderate regression which in turn was followed by recurrence and more or less pronounced secondary cycles of proliferation. In all cases of outspoken infection, there was diffuse involvement of testicle, tunic, epididymis, and cord, but as the infection progressed, the lesions underwent many transformations, so that a variety of lesions was formed from processes which in the beginning were of a common type. Eventually, the reaction became more irregular and the infection became centered in one or more foci which were commonly situated in the epididymis, tunics, scrotum, or mediastinum testis. These centers served as residual foci of infection. The duration of the testicular process was found to be very variable. In some animals, the entire reaction consisted of but a single sharp cycle, and the local infection was terminated by crisis within 4 to 6 weeks after inoculation. As a rule, the period of active infection was from 2 to 4 months, and quiescent or inactive lesions not infrequently lasted for from 4 to 6 months. In exceptional instances, local infection persisted for more than a year.
Synthesis and photoactivity of novel 5-arylthianthrenium salt cationic photoinitiators

5-Arylthianthrenium salts are a class of efficient triarylsulfonium salt photoinitiators for cationic polymerization. These compounds were prepared by a simple, straightforward, versatile, and high yield route. The new photoinitiators were characterized by standard analytical and spectroscopic techniques, and their activity as cationic photoinitiators was compared with related triarylsulfonium salts of similar structures using Fourier transform real-time infrared spectroscopy. Through the use of electron-transfer photosensitizers, the response of these photoinitiators can be readily spectrally broadened into the long-wavelength UV–visible regions of the spectrum. The results obtained suggest that 5-arylthianthrenium salts are potential replacements for now available triarysulfonium salt photoinitiators in many applications. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3465–3480, 2002
RNA Tetraloop Folding Reveals Tension between Backbone Restraints and Molecular Interactions

In RNA, A-form helices are commonly terminated by tetraloops or 3' dangling ends. Aside from helices themselves, these helix-breaking motifs appear to be among the most frequent and repetitive structural elements of large folded RNAs. We show here that within a frequent type of tetraloop, cGNRAg (G is guanine, N is any base, R is purine, A is adenine), a tension exists between the backbone torsional energy of the loop and the energy contributed by molecular interactions (stacking and pairing). A model in which favorable bond rotamers are opposed by favorable stacking and pairing interactions is consistent with our observation that release of torsional restraints upon conversion of one or more loop riboses to more flexible trimethylene phosphate(s) contributes favorably to the enthalpy of folding. This effect presumably results from improved stacking and hydrogen-bonding interactions upon release of torsional restraints. The most obvious possibility for improving molecular interactions is a repositioning of A, which is proximal to the unfavorable torsion angles in native cGNRAg tetraloops, and which is unstacked on the 3' side and unpaired (it forms a single hydrogen bond with the opposing G). This tension between favorable bond rotamers and favorable molecular interactions may be representative of a general evolutionary strategy to prevent achievement of deep and irreversible thermodynamic wells in folded RNAs. Finally, we observe a simple stacking substructure with conserved geometry and sequence that forms a scaffold for both tetraloops and 3' dangling ends. It seems that simple substructures can build RNA motifs, which combine to establish the fundamental architecture of RNA.
Legacies of land use and recent climatic change: the small mammal fauna in the mountains of Utah.

Abstract: Climate warming will continue alongside human modification of the landscape. Therefore, studying systems modified by land use may highlight factors that mitigate or exacerbate predicted biological responses to ongoing climate warming. Using historical museum specimen records and recent field surveys, I examine temporal patterns in the ecological dynamics of the small mammal fauna on five mountain ranges in central Utah over time intervals of 27–53 years during the past century. This landscape was heavily modified by livestock grazing early in the twentieth century and since then has witnessed a steady decline in grazing intensity. In general, at regional and landscape scales, species preferring mesic habitats increased in percent abundance, rank abundance, and rank occurrence over time. This result is opposite that predicted from regional climate trends and probably represents the recovery of forest conditions following a release over time from earlier periods of severe overgrazing. Decreased gr...
Orthostatic Responses in Patients with ODD Pacemakers: Signs of Autonomic Dysfunction

UNLABELLED Responses to orthostasis may be altered in states associated with autonomic dysfunction. Computerized impedance cardiography, a noninvasive method for continuous assessment of stroke volume and mean blood pressure, was utilized to study the postural hemodynamic changes in eight normal and 27 patients with DDD pacemakers. Twenty patients with complete heart block (five with heart failure) were studied in the VDD mode and seven patients with sick sinus syndrome were assessed in DVI (four) or VDD (three). The results with pacemaker patients are significantly different from those observed in normal. Pacemaker patient responses to standing included: (1) a reduction in systolic, diastolic, and mean blood pressure; (2) an increase in heart rate in patients with intact sinus node function and no change in patients with sick sinus syndrome; and (3) stroke volume was unchanged in patients with sick sinus syndrome or heart failure and only modest reduction occurred in the remaining patients. CONCLUSIONS (1) No reduction in stroke volume during upright posture occurs in DDD patients with sick sinus syndrome and this appears to be a compensatory reaction to an inadequate heart rate response to standing; (2) The hemodynamic response of DDD patients to the assumption of an upright posture is consistent with autonomic dysfunction; and (3) The primary cause for autonomic dysfunction in DDD patients may be the asynchronous ventricular depolarization caused by right ventricular pacing.