cssi/SciSciGPT-SciSciNet huggingface dataset:
Brain and serum levels of choline and lecithin resulting from long-term administration

Choline and phosphatidylcholine tissue concentrations were examined in mice treated with long-term (18–22 month) dietary choline enrichment, choline deficiency, or phosphatidylcholine enrichment. There were no significant differences found in choline levels among the dietary groups in any of the tissues examined: plasma, erythrocytes, cortex, hippocampus, and striatum. In contrast, the concentration of phosphatidylcholine in both the choline enriched and phosphatidylcholine enriched groups were significantly increased in the cortex, compared to the choline deficient group, and in the striatum, compared to control. No differences in phosphatidylcholine concentration were found in the hippocampus or plasma between any of the dietary groups. These results are in contrast to the reported effects of acute or short-term choline and phosphatidylcholine treatment and indicate that there may be differences between the effects of short-term and long-term administration on the blood and brain levels of choline and phosphatidylcholine.
Central hypogonadism: distinguishing idiopathic low testosterone from pituitary tumors.

Objective: To attempt to determine clinical or hormonal characteristics that could help distinguish benign idiopathic low testosterone (ILT) from pituitary tumor. Methods: On retrospective review of medical records of patients encountered by Johns Hopkins endocrine staff between 1985 and July 1995, 64 patients who fulfilled our enrollment criteria—27 men with ILT and 37 patients with imaging-proven pituitary tumor—were identified. Men 21 years of age or older needed to have had serum testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin levels measured before hormonal replacement therapy or pituitary tumor extirpation (or both) and a high-quality imaging scan (computed tomography or magnetic resonance imaging) done and interpreted by the Johns Hopkins radiology staff. Results: In comparison with men who had ILT, men with pituitary tumors had similar serum testosterone levels and significantly higher serum levels of LH, FSH, and prolactin. In addition, significantly more men with pituitary tumors had visual field abnormalities, headaches, and symptoms of hypothyroidism in comparison with the men with ILT. In contrast, the group with ILT complained significantly more of impotence, erectile dysfunction, and depression than did the group with pituitary tumors. The age at initial assessment was comparable in both study groups. Conclusion: Although age at initial manifestation did not predict the presence of pituitary tumor, the group of men with tumors were more likely than those with ILT to have serum testosterone levels <150 ng/dL, higher serum gonadotropin and prolactin levels, and visual field abnormalities and less likely to have sexual dysfunction. Therefore, on the basis of our data, we recommend that men with these findings should be referred for a magnetic resonance image to exclude the presence of a tumor. (Endocr Pract. 1998;4:355-359)
Lead Fingers: Pb2+ Binding to Structural Zinc-Binding Domains Determined Directly by Monitoring Lead−Thiolate Charge-Transfer Bands

Here, we report that lead−thiolate charge-transfer bands (250−400 nm) can be used to monitor lead binding to cysteine-rich sites in proteins and report the application of this technique to determine the thermodynamics of lead binding to a series of structural zinc-binding domains. These studies reveal that Pb2+ binds tightly to structural zinc-binding domains with dissociation constants that range from KdPb = 10-9 to 10-14 M, depending on the number of cysteine residues in the metal-binding site. Competition experiments with Zn2+ lead to two striking conclusions: first, the two metals rapidly equilibrate, and second, the ratio of Pb2+ to Zn2+ bound to a particular site is determined by the relative affinities of the two metals for that site, rather than being under kinetic control. We conclude that Pb2+ should be able to compete effectively with Zn2+ for Cys4 sites under physiological conditions. Despite the fact that Pb2+ binds tightly to cysteine-rich structural zinc sites, circular dichroism and 1H NM...
Barrier island migration and onshore sediment transport, southwestern Delaware Bay, Delaware, U.S.A.

Abstract A detailed sediment budget for part of a rapidly migrating (3 m yr−1) barrier system of southwestern Delaware Bay demonstrates that longshore drift and other principal sources of sediment are insufficient to balance the sediment budget during 1926–1981. Changes in bathymetry from 1964 to 1984 indicate that erosion is occurring in shallow areas outside the surf zone. If approximately half of the sediment eroded offshore is transported onto the beach, the sediment budget balances. These results suggest that sand and gravel is supplied to the barriers of the study area from offshore. Several processes probably combine to carry sediment landwards. Tidal currents are weak, and probably rarely entrain sediment without the assistance of waves. Once entrained, sediment may be carried onshore by the combined influence of dominant ebb-tidal currents and frequent northwest winds. This process is probably also aided by a residual onshore shear stress associated with 2nd-order Stokes waves.
Regeneration and innervation in cultures of adult mammalian skeletal muscle coupled with fetal rodent spinal cord.

Abstract In a collagen-substrate culture, long strips of teased adult skeletal muscle fibers oriented toward ventral-root nerve fibers of fetal rodent spinal cord explant will regenerate rapidly as the neural outgrowth makes contact with the muscle. Trophic enhancement of the early regenerative capacity of muscle is relatively nonspecific and can also be produced by contacts with a variety of nonneural fetal cells. Myotubes of neurally deprived muscle can regenerate, show fibrillatory contractions, and develop transient cross striations at their peak of development in vitro, but soon afterwards, as in vivo, they atrophy. Further differentiation, maturation, and long-term maintenance require innervation, in vitro as well as in vivo. In culture this is dependent upon the organotypic development of both the central and peripheral nerve network of the spinal cord complex. Although electrophysiologic studies show that neuromuscular transmission can occur early in the second week after coupling, the junctional structures are primitive and definitive loci of cholinesterase activity are not discernable (at the light microscopic level) until about a week later. During the following weeks in culture gradual maturation of the motor endplate structure occurs, including increased complexity of nerve terminals and postsynaptic specializations, as illustrated by silver impregnation, cholinesterase staining, and other histologic techniques. The ordered progression of skeletal muscle regeneration and maturation through spinal cord innervation in vitro is quite comparable to basic aspects of regeneration in vivo. Organotypic cultures provide, therefore, a reliable model system for studies of some of the mechanisms underlying muscle regeneration and the restoration of functional neuromuscular relations which may be difficult to analyze in situ.
Pollution of gravel spawning grounds by deposition of suspended sediment

Observations have shown that accumulation of fine sediment in the pores of spawning open-work gravel have a detrimental effect on stream biota. The rate of deposition is intimately linked to the concentration of suspended fines near the gravel bed. If interstitial voids in coarse sediment deposits are filled or covered with sand or inorganic fine materials, their habitat value is greatly reduced. In this paper, a simple method is proposed to predict analytically the concentration profile and transport of fine suspended sediment when a steady, uniform suspension flows from a sediment-covered bed to an open-work gravel bed. Comparisons of the analytical model predictions with previous laboratory observations show reasonable agreement. The proposed solution can be used to estimate “clarification distances” for streams carrying fine sediments over open-work gravel beds.
Fiber-based, soliton-tuned femtosecond optical source mid infrared spectral region

A fiber-based compact source of mid-infrared ultrafast laser pulses is presented. A polarization-maintaining fiber amplifier provides the pump pulses, while the signal pulses are derived from the same source by soliton self-frequency shifting in the same fiber. Noise and jitter of the fiber pulses are characterized.
Mediastinal emphysema and small cell lung cancer (SCLC): a case-report

We present a case of a 59-year-old man with small cell lung cancer (SCLC) who developed heavy thoracic pain because of spontaneous mediastinal emphysema. Autopsy documented a mucosal lesion in the posterior tracheal wall with air leak towards the mediastinum. The occurrence of spontaneous mediastinal emphysema in patients with small cell lung cancer has rarely been described in the literature.
Maximizing H2 production in Photosystem I/dithiol molecular wire/platinum nanoparticle bioconjugates

Photosystem I/dithiol molecular wire/nanoparticle bioconjugates have been shown to photocatalytically generate dihydrogen at linear rates when continuously illuminated. In an effort to maximize H2 production, the pH and ionic concentration of the solution, the mobility of the electron donor, the length and degree of saturation of the molecular wire, and the intensity of the light were systematically investigated. Optimal conditions included a solution buffered at pH 6.0, cross-linked plastocyanin, rebuilt spinach PS I, and the use of 1,4-benzenedithiol to connect PS I to the Pt nanoparticle. Illumination of this optimized Photosystem I/dithiol molecular wire/nanoparticle bioconjugate at a light intensity of 70 μE m−2 s−1 generated a measured one time H2 production rate of 312 μmol H2 mg Chl−1 h−1.
Fluid closures which mimic wave-praticle interactions in strong Langmuir turbulence.

A new two-time-scale model of strong Langmuir turbulence has been constructed, using higher-moment fluid equations with dissipative closures designed to better simulate Vlasov theory predictions of linear wave properties, and to treat collisionless heating of particles by waves. Numerical solutions are carried out in a study of electron heating associated with collapse and burnout of a large-amplitude initial Langmuir wave and in a study of radiation-driven Langmuir turbulence interacting with ion-acoustic quasimodes in plasmas with ${\mathit{T}}_{\mathit{e}}$\ensuremath{\approxeq}${\mathit{T}}_{\mathit{i}}$.
Separation of multi-component NRM: A general method

A method is presented which can successfully isolate components of remanent magnetization having intermediate relative stability in a single rock sample which contains any number of remanence components with overlapping coercivity or blocking temperature spectra. The approach consists of analysis of the path swept out by the vector destroyed during a detailed alternating field or thermal demagnetization run. The point of intersection determined for any two neighboring great circle segments identified in such a difference vector path defines the direction of such a component. Samples cored from a fragment of a Jurassic pillow basalt, shown to contain several components of magnetization, serve to illustrate the utility of the method for the case when the Zijderveld approach is unsuccessful.
Classification of voltage problems in electric power systems

Abstract In this paper sufficient mathematical and operating conditions are defined for distinguishing between voltage problems with insignificant frequency changes and voltage problems accompanied by frequency instabilities. With this as the main classification, additional conditions are introduced under which voltage related problems are either of a steady state character, or they evolve as the mid-/long-term phenomena only (in contrast to very fast, transient stability type phenomena). Within the first class (insignificant frequency changes) two distinct groups of voltage problems could arise, the most common of which is the existence of post-contigency voltage outside of operating limits. The other group of voltage problems within the first class is reflected in a small signal instability of an existing load flow solution. Assuming that a post-contingency load flow solution exists, mathematical and operating conditions are reviewed under which these problems occur. New conditions are established for preventing the second group of voltage problems from this class, i.e. small signal voltage instabilities. As a result, voltage related problems in this class are guaranteed to be, at worst, mid-/long-term type phenomena. Within the second class (accompanied by frequency instabilities), two groups of voltage-related problems occur. The first group is reflected in persistent but bounded terminal voltage oscillations, primarily contributed by the unstable mode associated with the rotor angle. The second group is characterized by unbounded changes of terminal voltages, primarily contributed by the unstable mode in field-flux voltage E q ′ . In this paper, conditions are derived under which persistent but bounded voltage oscillations take place, as opposed to unbounded changes of state representing voltage dynamics, such as field-flux voltage E q ′ of the machine and its terminal voltage V t .
A region-based compilation technique for dynamic compilers

Method inlining and data flow analysis are two major optimization components for effective program transformations, but they often suffer from the existence of rarely or never executed code contained in the target method. One major problem lies in the assumption that the compilation unit is partitioned at method boundaries. This article describes the design and implementation of a region-based compilation technique in our dynamic optimization framework, in which the compiled regions are selected as code portions without rarely executed code. The key parts of this technique are the region selection, partial inlining, and region exit handling. For region selection, we employ both static heuristics and dynamic profiles to identify and eliminate rare sections of code. The region selection process and method inlining decisions are interwoven, so that method inlining exposes other targets for region selection, while the region selection in the inline target conserves the inlining budget, allowing more method inlining to be performed. The inlining process can be performed for parts of a method, not just for the entire body of the method. When the program attempts to exit from a region boundary, we trigger recompilation and then use on-stack replacement to continue the execution from the corresponding entry point in the recompiled code. We have implemented these techniques in our Java JIT compiler, and conducted a comprehensive evaluation. The experimental results show that our region-based compilation approach achieves approximately 4p performance improvement on average, while reducing the compilation overhead by 10p to 30p, in comparison to the traditional method-based compilation techniques.
Cigarette smoking and the risk of systemic lupus erythematosus: a meta-analysis.

Objective Existing studies present conflicting evidence for the role of cigarette smoking as a risk factor in the development of systemic lupus erythematosus (SLE). We performed an extensive search of the medical literature for all studies examining this relationship, and performed a meta-analysis to arrive at a more precise estimate of effect. Methods We performed a computerized literature search for all studies (in all languages), using Medline and EMBASE (1966 to present) and the Cochrane Collaboration database, and completed hand searches of relevant bibliographies and abstracts of conference proceedings. Several investigators systematically extracted data from the relevant studies. Unpublished data were obtained from the author of one abstract. Studies were examined in aggregate for heterogeneity and publication bias. The relationships of current smoking and past smoking (prior to the onset of SLE) to development of SLE were analyzed separately. Results Fifty-two studies were identified and chosen for detailed review. Of these, 9 (7 case–control and 2 cohort studies) were appropriate for inclusion in our meta-analyses. For current smokers compared with nonsmokers, the odds ratio (OR) for development of SLE was significantly elevated (OR 1.50, 95% confidence interval [95% CI] 1.09–2.08). Former smokers, compared with nonsmokers, did not demonstrate an increased risk of SLE (OR 0.98, 95% CI 0.75–1.27). Several subgroups were also analyzed. Conclusion Our meta-analysis of the 7 existing case–control and 2 cohort studies revealed a small but statistically significant association between current smoking and development of SLE. However, no association between past smoking and development of SLE was observed.
BIG CITY MAYORS: POLITICAL SPECIALIZATION AND BUSINESS DOMINATION IN THE 19TH AND 20TH CENTURIES

An examination of mayoral recruitment in 19 major American cities from 1820 to 1995 finds that mayors are now more likely to have prior political experience, serve longer in office, and have previo...
Amorphous Metal/Oxide Nanolaminate

Bilayers of sputtered amorphous multicomponent metal films (AMMFs) and solution deposited amorphous oxide films have been reproducibly deposited with varying thicknesses of 20, 25, and 30 nm to for...
Sources of Expectancy Information among College Coaches: A Qualitative Test of Expectancy Theory:

Expectancy theorists contend that coaches utilize a variety of impression cues for information-gathering tasks. The purpose of this study was to examine college coaches' perceptions of athletes by exploring the sources that coaches use to assess athlete achievement. Eighteen NCAA Division I intercollegiate head coaches participated in semi-structured interviews. An inductive/deductive content analysis revealed the existence of six expectancy dimensions for coaches: personality, performance, personal, cognitive, mistakes, and knowledge from others. The most salient dimensions were personality and performance cues comprising 42% and 32% of the raw data quotes respectively. Team and individual sport coaches agreed that work ethic and motor skills were very important, whereas they differed on the importance of team qualities, mental strategy, and sport-specific skills. Future research directions include the creation of a quantitative assessment tool to access sources of expectancy information among college co...
Component shape optimization using bem

Abstract Interest in shape optimization using the boundary element method is motivated largely by its relative ease in mesh generation. Unlike the well-known finite element method, discretization for the boundary element technique is required only on the boundary of the components. In this paper, displacement sensitivities required for design optimization are analytically obtained by differentiating the basic integral equation on the boundary directly. A special identity is used to remove all singular integrals from the sensitivity equations. The stress sensitivities are obtained by differentiating the shape function in each boundary element as in the finite element analysis. A modular approach for shape optimization used in the finite element context is employed for the boundary elements. Flexibility of the modular approach allows one to take full advantage of the advancements in each discipline involved in shape optimization such as the boundary element method. Procedures for implementing the sensitivity formulation into a commercial boundary element code are addressed. An infinite two-dimensional plate with an elliptical hole and a two-dimensional fillet bar problem are optimized to demonstrate the use of the approach. Although the modular approach is demonstrated by two-dimensional elasticity problems, it is straightforward to apply the same concept to solve three-dimensional problems.
Human Melatonin Production Decreases With Age

The purpose of this study was to investigate the effects of time of year and demographic variables on the amplitude of melatonin production in normal human subjects. Melatonin production was estimated by measuring the overnight excretion of its major urinary metabolite, 6-hydroxymelatonin. Urine was collected on three consecutive nights in the summer from a sample of 60 normal subjects balanced for sex and age. The collections were repeated in a subgroup during the winter. Melatonin production clearly declined with age but was not influenced by other demographic variables or by season of the year.
Superior vena cava obstruction in small cell bronchogenic carcinoma. Clinical parameters and survival.

A clinical pathologic review with analysis of prognostic factors was conducted in 56 patients who were seen at the University of Texas M. D. Anderson Hospital and Tumor Institute between 1969 and 1980 with the syndrome of superior vena cava (SVC) obstruction secondary to small cell bronchogenic carcinoma. Most patients were men (60%), nonambulatory (61%), and had demonstrable extrathoracic disease (70%). The most common symptoms and signs of SVC obstruction were jugular venous distention (100%), swollen face (88%), and dyspnea (50%). Swollen arms (34%) and engorgement of thoracic veins (32%) were also common. Initial treatment consisted of irradiation alone, 17 patients (30%); chemotherapy alone, 32 patients (57%); or both, 7 patients (13%). Patients receiving chemotherapy initially had poor prognoses, as evidenced by the greater proportion of nonambulatory patients (72%) in this group. All but two patients received chemotherapy at some point during their clinical courses. There were 12 (21%) early deaths; 2 (12%) in the radiation arm; 9 (28%) in the chemotherapy arm; and 1 (14%) in the combined modality group. All treatment modalities were rapidly effective in controlling the symptoms associated with SVC obstruction. Within 1 week from onset of treatment, 9 of 14 (64%) evaluable patients responded to irradiation, 23 of 23 (100%) to chemotherapy, and 5 of 6 (83%) to combined modality treatment. The type of initial treatment did not influence survival significantly, although patients who achieved complete clinical remissions survived longer (median, 62 weeks). Death was usually due to disease progression in distant sites. Multivariate analysis indicated that the most important prognosticators of patients' survival were pretreatment performance status, disease-extent score, and age. Cancer 52:2165-2172, 1983.
Uphill transport of a dilute solute in mass separation devices with reactive co-transport membranes

Abstract Uphill transport of a solute species against its concentration gradient by a mobile carrier species, which couples the flux of two species in the same direction, is known as co-transport. For fully developed, one-dimensional, laminar flow of a Newtonian fluid in either a parallel plate or a hallow fiber mass separator, the uphill mass transfer rate is analyzed numerically. The effect of diffusion and reaction parameters on uphill transport is investigated. The uphill transport of a dilute solute for a carrier-coupled co-transport membrane process is shown to depend on the wall Sherwood number, the maximum co-transport factor, the dimensionless equilibrium constant of the chemical reaction, the ratio of the initial concentrations of the two coupling species, and the initial concentration difference of the solute across the membrane.
Language, Rhetoric, and AIDS: The Attitudes and Strategies of Key AIDS Medical Scientists and Physicians

This article examines the experiences and rhetorical actions of key medical scientists and physicians who have treated, studied, and written about Acquired Immune Deficiency Syndrome since the beginning of the epidemic. Those first to describe the disease report that the rhetorical challenge was convincing their audience to accept the novel idea of acquired immune deficiency and to see the cases they described as an emerging medical catastrophe. The biological, social, and linguistic complications of AIDS and the failure of traditional treatments forced the professionals interviewed to develop new care practices such as more horizontal communication with patients and a holistic view of a patient's needs. Responding to the need to educate and persuade peers and the public about appropriate actions in treating and preventing the disease, these professionals participated in rhetorical action that negotiated between “old” practices and attitudes and “new” problems that required changes in practice and attitudes.
Single-SectionFabry-Perot Mode-Locked Semiconductor Lasers

We present a review of the theoretical models and experimental verification of the single-section Fabry-Perot mode-locked semiconductor lasers based on multiple-spatial-mode (MSM) coupling. The mode-locked operation at the repetition rates of 40 GHz and higher and the pulse width of a few picoseconds are confirmed by the intensity autocorrelation, the fast photo detection and RF spectrum, and the optical spectral interference measurement of ultrafast pulse. The spatial mode coupling theory of single-section Fabry-Perot mode-locked semiconductor lasers is also reviewed, and the results are compared with the experimental observations. The small signal modulation response of these lasers, which exhibits high-frequency responses well beyond the relaxation oscillation resonance limit, is also modeled theoretically, and the simulation is verified by the experimental measurements.
Investigations into the growth behaviour of a toluene‐degrading Pseudomonas strain, taking the high vapour pressure of toluene into consideration

A toluene-degrading Pseudomonas species isolated from waste water was studied with regard to its growth behaviour. The dependence of the growth rate on the pH value, on the toluene concentration and on temperature, as well as the O2 consumption of the isolate were determined. The fact that toluene is a highly volatile substrate, which is present both in the liquid and in the has phase of a reactor, was considered in the experiments. It is shown that the volatility of toluene has to be taken into consideration for an accurate determination of the toluene concentration in the medium.
In vivo and ex vivo gene transfer to the brain.

Abstract The use of gene transfer techniques to express novel proteins within different cellular populations has provided insights into the function and plasticity of the brain. Recently, this technique has been successfully used to explore physiological processes within the CNS and to intervene in neurodegenerative disease and cancer. Progress in manipulating transgene products in vivo andin achieving cell-specific targeting of genetic material offers promise for enhancing the usefulness of this technique and its therapeutic potential for treating human disorders of the CNS.
Experimental Transmission of Langat (Tick-Borne Encephalitis Virus Complex) Virus by the Soft Tick Ornithodoros sonrai (Acari: Argasidae)

Laboratory studies determined that the soft tick Ornithodoros sonrai Sautet & Witkowski is a competent vector of Langat (tick-borne encephalitis virus complex) virus. When ticks fed on suckling mice having a mean viremia of 10(7.2) plaque-forming units per ml, 52% (n = 208) became infected, and 84% (n = 87) of the infected ticks transmitted virus by bite when fed individually on suckling mice > or = 27 d after the infectious blood meal. Overall, 79 of 184 (43%) of ticks exposed to the original viremic mice individually transmitted virus by bite when tested up to 351 d after the infectious blood meal. In addition, ticks transmitted virus both transstadially and transovarially. Some ticks that transmitted virus during their first transmission attempt were retested. These ticks transmitted virus during 81 (99%) of 82 refeeding attempts, including ticks that transmitted virus 512 d after the initial infectious meal. Therefore, Ornithodoros spp. should be considered as potential vectors of Langat and other tick-borne encephalitis viruses.
Medical management of vesicourachal diverticula in 15 cats with lower urinary tract disease

The biological behaviour of radiographically detectable vesicourachal diverticula in 13 male and two female cats with haematuria, dysuria, and, or, urethral obstruction was evaluated following spontaneous or treatment-induced remission of lower urinary tract disease. The observation that diverticula are larger in obstructed than non-obstructed cats supports the hypothesis that the higher prevalence of diverticula in males is associated with a higher prevalence of urethral obstruction in males. Complete resolution of vesicourachal diverticula occurred in all 15 patients. Regression of diverticula following eradication of bacterial urinary tract infections with antimicrobial agents and, or, medical dissolution of urocystoliths indicates that diverticulectomy is not always warranted. It is probable that diverticula heal within two to three weeks following elimination of increased intraluminal bladder pressure.
Illness and injury among female employees at the US Department of Energy

There are few studies that examine the overall morbidity of women in industrial settings. Results from a surveillance program of 21,294 female employees of the US Department of Energy for a 12-month period are presented. Illness/absence data of 5 or more workdays were collected from an epidemiologic surveillance program at eight sites. Approximately 11% of the workforce reported an absence of 5 or more workdays in the 12-month period. The five most common disease categories accounted for 70% of all illness or injury absences among female workers. These were respiratory illnesses (22.1%), musculoskeletal disorders (13.2%), injury and poisonings (13.0%), genitourinary illnesses (9.8%), and digestive illnesses (8.8%). Sprains and strains were most frequently attributable to workplace conditions.
SU-FF-I-19: Scatter Correction for the On-Board Imager Using a Kernel Model

Purpose: To develop an efficient analytical scatter correction algorithm for the On‐Board Imager (OBI) for both the center‐detector and offset‐detector geometries used for cone‐beam computed tomography(CBCT). The offset‐detector geometry is used for larger transaxial field‐of‐views and is particularly challenging due to the asymmetric nature of the associated scatter profile and higher overall scatter‐to‐primary ratios. Methods and Materials: A scatter kernel model was implemented. The cone‐beam was modeled as an array of pencil beams. For each of the pencil beams, a scatter point‐spread function was determined based on measured attenuation values and prior simulations of a polychromatic x‐ray beam directed through uniform material. The total scatter estimate was then derived from the cumulative response of each of the scatter point‐spread functions. The model also included the responses of the detector and anti‐scatter grid. To test the model, a pelvis phantom and a cylindrical water phantom were imaged on a table‐top system with hardware and geometric parameters that matched the OBI in offset‐detector configuration. The accuracies of the estimates were determined by comparisons with experimental scatter measurements. Results: Accuracies of the estimates were excellent away from the edges of the phantoms. Hounsfield Unit (HU) errors in the reconstructed images were reduced from over 20% pre‐correction to <2% after correction in the bulk of the image. However, near the edges of the phantoms, scatter was underestimated which resulted in residual HU errors that were on the order of 10%. Conclusions: The results demonstrate the potential for successful implementation of a computationally efficient scatter‐kernel model for the OBI. Work is underway to improve scatter estimates for rays near the edges of objects. Conflict of Interest: Employees of Varian Medical Systems.
Improving properties of GaInNAs with a short-period GaInAs/GaNAs superlattice

Short-period superlattices (SLs) of GaInAs/GaNAs were grown by gas-source molecular beam epitaxy. Hall measurement shows electron mobility is improved by a factor of almost two. Improvement of electron mobility can be attributed to the smaller effective mass of the SL structure. The photoluminescence (PL) intensity is improved by rapid thermal annealing (RTA). The PL intensity of digital alloys is 2.5-3 times higher than that of the random alloy at room temperature, and the improvement is even greater at low temperature (10 K) by a factor of about 12. The optimized RTA condition for short-period SLs is 700 C and 10s in N 2 ambient. Photoconductive decay measurements show longer carrier lifetime for the SL samples, 0.2 μs vs. 0.1 μs for the random alloy, which could be caused by charge separation due to the type-II band lineup of the GaIn 0.08 As/GaN 0.03 As SLs.
Relative Adrenal Insufficiency in the Critical Care Setting: Debunking the Classic Myth

Background Classic teaching states that chronic adrenal insufficiency is associated with hyponatremia, hyperkalemia, hypercalcemia, hypoglycemia, and eosinophilia. We hypothesize that these diagnostic markers do not predict relative adrenal insufficiency (RAI) in the critically ill or injured patient.
Relative pupillary sparing third nerve palsies. To arteriogram or not

Ten consecutive patients with acute relative pupillary sparing third nerve palsies were enrolled in a prospective study to determine the prevalence of intracranial aneurysm. All patients were imaged with either cerebral angiography or magnetic resonance angiography. None of the patients demonstrated an intracranial aneurysm. The prevalence of aneurysm in patients with relative pupillary sparing third nerve palsies may be low enough to preclude the use of routine angiography in this condition.
Identification of Fetal Atrial Flutter by Doppler Tissue Imaging

A 26-year-old woman presented at 33 weeks of gestation with a singleton fetus with tachycardia. A complete fetal echocardiogram revealed a structurally normal fetal heart without signs of hydrops. The fetal heart rate was between 200 and 220 bpm. Evaluation of the rhythm with pulsed Doppler and M-mode scanning was not definitive. Fetal Doppler tissue imaging color M-mode scanning was performed …
Synergistic activation of β-galactosidase by Na+ and Cs+

Abstract The rate of hydrolysis of ortho -nitropheno-β- d -galactopyranoside ( o -NPG) by β-galactosidase from Escherichia coli was measured in the presence of varying concentrations of substrate, Na + and Cs + . The results were analyzed by means of Dixon plots. Na + increases both the affinity of the enzyme for the substrate and the maximal rate of hydrolysis at substrate saturation. The substrate increases the affinity of the enzyme for Na + by an amount proportional to the increase in substrate affinity produced by the Na + . It is shown that this mutual effect of activator and substrate on each other's affinities is a thermodynamic necessity. Cs + increases the rate of hydrolysis at concentrations lower than 0.01 m ; the extent of this activation depends on the Na + concentration. Above 0.01 m Cs + becomes inhibitory. A model based on inductive changes in the active site which result from the binding of substrate and ions is proposed to explain the observed facts.
Fed-batch bioreactor control using a multi-scale model

The fed-batch mode of bioreactor operation is amongst the most commonly used in the fermentation industry, and fed-batch bioreactors are difficult to control due to their nonlinear and dynamic behavior. In this work a multi-scale model is used that describes the dynamic behavior of aerobic fed-batch cultures of Saccharomyces cerevisiae. Open-loop and closed-loop control issues are addressed for bioreactor optimization and control with the goal of maximizing the ethanol concentration at the end of the batch. Nonlinear optimization techniques are used off-line to obtain an open-loop optimal substrate profile, and a shrinking horizon nonlinear quadratic dynamic matrix control (SHNLQDMC) algorithm is used for online closed-loop control. Particular emphasis is placed upon disturbance compensation techniques for closed-loop operation. The controller achieves an admirable nominal performance finishing within 1% of the final open-loop optimal ethanol concentration. For disturbance compensation it was found that a closed-loop re-optimization strategy improved the final ethanol concentration by 40% compared to the case when the open-loop optimal profile was employed. Finally, it was observed that reducing the sample time considerably improved the controller performance and made the system more robust to disturbances.
Water–cement ratio gradients in mortars and corresponding effective elastic properties

Abstract Water–cement ratio gradients are modeled through the interfacial transition zone (ITZ) of a mortar with spherical inclusions. The model is a function of the over-all water–cement ratio, volume fraction and radius of sand, specific gravity of cement and thickness of ITZ. Based on experimental data from the literature, the dependence of saturated, homogeneous cement paste is modeled as a function of water–cement ratio. Subsequently, the effective bulk and shear moduli for mortars are determined using a generalized self-consistent method. Finally, application of the model to data in the literature pertaining to elastic wave speeds in saturated mortars composed of 20–30 screened sand with an overall water–cement ratio of 0.3 yielded a mean ITZ thickness of 48.3 μm.
A Wavelet-Denoising Approach Using Polynomial Threshold Operators

This letter presents a new class of polynomial threshold operators for denoising signals using wavelet transforms. The operators are parameterized to include classical soft-and hard-thresholding operators and have many degrees of freedom to optimally suppress undesired noise and preserve signal details. To avoid the complicated process of signal model identification for specific type of signals, a least squares optimization method is proposed for the polynomial coefficients. Our study shows that the proposed term-by-term, fixed-threshold operator can perform as well as adaptively applied, scale-dependent soft and hard thresholding approaches.
A Creative Way to Utilize Social Media to Enhance Fitness and Health Knowledge

As youth are becoming less active and more obese, America is ever increasingly becoming a country of nonmovers (Centers for Disease Control and Prevention, 2010; Child Trends Data Bank, 2010; Hayni...
Schizotypal Symptoms in the Relatives of Schizophrenia Patients: An Empirical Analysis of the Factor Structure

This study examined the nature of schizotypal symptoms in the relatives of schizophrenia patients and investigated phenomenological differences in symptomatology manifested by a familial sample and a clinical sample of personality disorder patients. Confirmatory factor analyses were used to test models of DSM-III-R schizotypal symptoms in the first degree relatives (n = 172) of schizophrenia patients. A multi-sample analysis was conducted to determine whether the same model adequately described the schizotypal symptoms rated in the relatives of schizophrenia patients and in clinically selected personality disorder patients. The results indicated that a three-factor model consisting of cognitive/perceptual, interpersonal, and disorganization factors yielded the best fit to the data from the relatives of schizophrenia patients, but that this model did not adequately describe both the relatives of schizophrenia patients and personality disorder patients. These findings indicate that the structure of schizotypal symptoms in the relatives of schizophrenia patients is similar to the three-factor model of schizophrenia symptoms often reported, but not the same as the structure of schizotypal symptoms in clinically selected personality disorder patients.
Incentive-Driven P2P Anonymity System: A Game-Theoretic Approach

Anonymous communication systems built on P2P infrastructures using anonymity forwarders are frequently affected by the churn problem, i.e. frequent joins and leaves of nodes. The problem unavoidably affects the quality of provided anonymity: The availability of anonymity forwarders will be decreased, which reduces the anonymity set; and the frequency of path reformation will increase, which increases the chance of successful intersection attacks. We propose an incentive-based P2P mechanism as an approach to providing reliable anonymity forwarding. It uses incentives to induce the peer nodes to provide anonymity forwarding as reliable service and to make stable and distributed forwarding decisions to minimize the frequency of path reformations. To support incentive, a payment system has been designed which meet the anonymity requirement and can handle typical scenarios of cheating and malicious attacks. To make sound forwarding decisions, we use game theory to carefully design the forwarding strategies used by the peer nodes. We have used event-driven simulations to evaluate the quality of anonymity provided by the mechanism under high churn and with the presence of malicious nodes. The results show that the quality of anonymity is maintained in those scenarios.
VWF self-association: more bands for the buck.

In this issue of Blood , Dayananda and coworkers demonstrate that fluid-phase VWF can bind homotypically to platelet VWF, strengthening platelet-platelet association and enhancing platelet activation.[1][1] The hemostatic function of von Willebrand factor (VWF) depends on its degree of
Risk of future arterial cardiovascular events in patients with idiopathic venous thromboembolism

Venous and arterial thromboses have traditionally been considered distinct pathophysiologic entities. However, the two disorders have many features in common, and there is evidence that persons with venous thrombosis may be at greater risk for arterial events. The pathogenesis of both disorders includes endothelial injury, platelet activation, elevated levels of intrinsic clotting factors and inflammatory markers, increased fibrinogen, and impaired fibrinolysis. In addition, older age, obesity, dyslipidemia, and smoking predispose to both venous and arterial thrombosis. While the evidence that arterial disease is a risk factor for venous thrombosis is inconclusive, arterial disease does appear to occur with a modestly increased frequency in patients with a history of venous thromboembolism. Reported odds ratios in such patients were 1.2 for myocardial infarction, 1.3 for stroke, 2.3 for carotid plaque, and 4.3 for coronary calcification. Of note, in persons under age 40 with unprovoked venous thrombosis, the odds ratio for acute myocardial infarction was as high as 3.9. In general, however, venous disease is considered to be a weak risk factor for arterial thrombosis, and the use of agents specifically targeted to the prevention of heart attack or stroke in the majority of persons with VTE cannot be recommended at present.
Attitudes, Stress, and Satisfaction of Staff Who Care for Residents With Dementia

Purpose: Considering the increasing proportion of residents in long-term care who have dementia, and the important influence that direct care providers have on resident quality of life, this study explores the dementia-related attitudes of residential care/assisted living (RC/AL) and nursing home staff, as well as their work stress and satisfaction. Design and Methods: Data were derived from interviews with 154 direct care providers from 31 RC/AL facilities and 10 nursing homes who participated in the Collaborative Studies of Long-Term Care. Results: Stress was more often reported by care providers who had been working for 1 to 2 years (compared with longer); in addition, those who had been working for 1 to 2 years were more likely to espouse hopeful or person-centered attitudes than those who had been working for a longer period of time. Also, a person-centered attitude related to satisfaction, and perceived competence in providing dementia care was consistently associated with dementia-sensitive attitudes and job satisfaction. Implications: Attending to the welfare and ongoing training of workers who have demonstrated job commitment may lessen their tendency to become jaded over time or seek job opportunities elsewhere. Further, the attitudes the staff hold related to dementia and the training they receive to provide dementia care are important for their own
Cognitive Processing through the Interaction of Many Agents

A collection of interacting autonomous entities, called ‘agents’, may be capable of creating complex cognitive processes and behaviors, which could not be achieved by a single agent, without the need for outside centralized coordination or control. Keywords: multi-agent systems; emergent behavior; self organization distributed systems; society of agents
Issues in aging in individuals with life long disabilities

Introduction: The major research data and findings related to aging among persons with developmental disabilities are discussed. Topics addressed include prevalence and mortality rates, as well as the effects of aging on the sensory systems, the neuromusculoskeletal system and the cardiopulmonary system. The discussion also focuses on the clinical implications of these changes among aging individuals with developmental disabilities. Conclusion: Although the individual needs of persons with developmental disabilities vary greatly, knowledge of the effects of aging on this group of individuals can facilitate more effective healthcare by physical therapists for all adults with developmental disabilities.
The Impact of Red Wine on Blood Pressure Dizziness Continues

We read with great interest the article of Chiva-Blanch et al recently published in your journal.1 This randomized controlled trial evaluates the impact of dealcoholized red wine (DRW) on blood pressure (BP) in patients with high cardiovascular risk and concludes on its ability to lower BP. Although excited about the interesting results of this trial, we think several concerns exist that, if addressed in future studies, might lead to a better understanding of the findings and a wider acceptance of the conclusions. First, office measurement has been used to evaluate the impact of various interventions on BP. Although not specified in the article, the patients were likely to have the interventions (ie, beverage intake) during evening hours. As such, there has been an interval of several hours between the intervention and the measurement of BP, which took place during the office visit the next day. It has been shown that repeated alcohol intake has a biphasic impact on BP (ie, initially decreasing, …
Paragonimiasis: Diagnosis and the Use of Praziquantel in Treatment

Paragonimiasis was diagnosed in eight patients: five with sputum specimens positive for characteristic ova and three with only stool specimens positive for ova. Clinical symptoms, roentgenograms and serologic findings appeared to correlate with severity of disease. All eight patients were treated with praziquantel (oral dose, 75 mg/kg of body weight daily for two consecutive days). Of seven patients who completed the treatment, six had ova-negative sputum and stool specimens by day 90; the seventh patient's specimens became ova negative by day 120. The eighth patient, who had failed to respond to prior treatment with bithionol, could not tolerate the daily dosage of 75 mg/kg because of nausea. Although he received the same total dose (150 mg/kg) over four days his specimens remained ova positive on day 90. Adverse effects included nausea (two patients), headache (one patient), and urticaria (two), the last effect possibly secondary to release of antigen from drug-damaged parasites. A review of the epidemiology, clinical presentation, and treatment of pulmonary paragonimiasis is presented.