cssi/SciSciGPT-SciSciNet huggingface dataset:
To share or not to share? Examining the factors influencing local agency electronic information sharing

The ability of local government agencies to effectively utilise technologies to share information constitutes a critical element in nationwide efforts to fight terrorism, combat crime, and protect citizen safety. Alarmingly, current practices have neither effectively transferred information that local government agencies need, nor adequately captured and propagated information generated by local authorities. The objective of this study is to understand the factors influencing local agency electronic information sharing. The results of an in-depth case study provide a comprehensive understanding of the technological, agency and environmental factors that promote or inhibit electronic information sharing by local agencies. An extensive set of recommendations is put forth to enable government officials to enhance the success of electronic information sharing initiatives. Moreover, the findings carry several important implications for theory and practice.
The influence of temperature and absorbed water on the fatigue crack propagation in nylon-6,6

Abstract The effect of absorbed water on the fatigue crack propagation (FCP) of nylon-6,6 was investigated over a range of test temperatures and is correlated with dynamic mechanical properties. Both the storage modulus, a measure of specimen stiffness, and the loss compliance, a measure of energy dissipation and hysteretic heating, influence FCP response. At a given temperature, fatigue resistance is greatest for a given water content corresponding to an optimum combination of storage modulus, E′, and loss compliance, D″. The use of an empirical shift parameter to normalize the temperature dependence of the FCP behaviour of nylon with various water contents is discussed.
Modeling Creep in Thermoplastic Composites

A creep model for unidirectionally reinforced fiber composites was devel oped based on a one-parameter potential function. The same potential function was used to describe plastic flow and time-dependent creep deformation. The material constants in the model were determined by using the uniaxial tension test of off-axis coupon specimens. In terms of effective stress and effective creep strain, the anisotropic creep behavior can be given by a stress-dependent master creep curve irrespective of loading direction relative to fiber orientation. DuPont's AS4/PEKK thermoplastic composites were used in the creep experiment. Results for both unidirectional and laminated composites were presented.
Pollen and radiolarian records from deep-sea core RC14-103: Climatic reconstructions of northeast Japan and Northwest Pacific for the last 90,000 years

Using modern pollen and radiolarian distributions in sediments from the northwest Pacific and seas adjacent to Japan to interpret floral and faunal changes in core RC14-103 (44°02′N, 152°56′E), we recognize two major responses of the biota of eastern Hokkaido and the northwest Pacific to climatic changes since the last interglaciation. Relatively stable glacial environments (∼80,000–20,000 yr B.P.) were basically cold and wet ( 8°C and >1200 mm mean annual temperature and precipitation, respectively), supporting climax broadleaf deciduous forest with Quercus and Ulmus/Zelkova, with surface waters in the northwest Pacific characterized by warm (>1.5°C) winter and cold (10.4°–14.3°C) summer temperatures. Climatic evidence from RC14-103 shows a high degree of local and regional variation within the context of global climatic change. Correlative ocean and land records provide the detailed input necessary to assess local/regional responses to variations in other key elements (i.e., solar radiation, monsoonal variations) of the northeast Asian climate system.
Demonstration that LSTRA cells have an elevated level of proteins phosphorylated on tyrosine residues

The LSTRA cell line has been shown to have an exceptionally high level of a tyrosine protein kinase (pp56lck). We now report that LSTRA cells also have a much higher level of proteins phosphorylated on tyrosine residues in comparison to several other cell lines with normal levels of pp56lck. The level of phosphotyrosine-containing proteins in LSTRA cells was comparable to that seen in K562 cells, a cell line known to have a constitutively active tyrosine protein kinase. These results provide evidence that LSTRA cells have an elevated level of in vivo tyrosine protein kinase activity, probably due to the overexpression and activation of pp56lck.
DESIGN CONSIDERATIONS AND ANALYSIS OF A COMPLEX MODULUS APPARATUS

An analytical assessment is made of an apparatus designed for the measurement of the complex shear modulus of viscoelastic materials. It is shown that simple measurements of amplitude ratio and phase angle are sufficient to determine the complex modulus at any point over a wide range of frequency and dynamic strain. Data obtained for butyl rubber and some experimental elastomers are presented.
Nanoparticle delivery of donor antigens for transplant tolerance in allogeneic islet transplantation.

Human islet cell transplantation is a promising treatment for type 1 diabetes; however, long-term donor-specific tolerance to islet allografts remains a clinically unmet goal. We have previously shown that recipient infusions of apoptotic donor splenocytes chemically treated with 1-ethyl-3-(3′-dimethylaminopropyl)-carbodiimide (donor ECDI-SP) can mediate long-term acceptance of full major histocompatibility complex (MHC)-mismatched murine islet allografts without the use of immunosuppression. In this report, we investigated the use of poly(lactide-co-glycolide) (PLG) particles in lieu of donor ECDI-SP as a synthetic, cell-free carrier for delivery of donor antigens for the induction of transplant tolerance in full MHC-mismatched murine allogeneic islet transplantation. Infusions of donor antigen-coupled PLG particles (PLG-dAg) mediated tolerance in ∼20% of recipient mice, and the distribution of cellular uptake of PLG-dAg within the spleen was similar to that of donor ECDI-SP. PLG-dAg mediated the contraction of indirectly activated T cells but did not modulate the direct pathway of allorecognition. Combination of PLG-dAg with a short course of low dose immunosuppressant rapamycin at the time of transplant significantly improved the tolerance efficacy to ∼60%. Furthermore, altering the timing of PLG-dAg administration to a schedule that is more feasible for clinical transplantation resulted in equal tolerance efficacy. Thus, the combination therapy of PLG-dAg infusions with peritransplant rapamycin represents a clinically attractive, biomaterials-based and cell-free method for inducing long-term donor-specific tolerance for allogeneic cell transplantation, such as for allogeneic islet transplantation.
Immune responses to Schistosoma haematobium infection

Urogenital schistosomiasis is one of the greatest single infectious sources of human morbidity and mortality known. Through a complex cycle of infection, migration and eventual maturation and mating, S. haematobium (the aetiological agent of urogenital schistosomiasis) deposits highly immunogenic eggs within the bladder and other pelvic organs, activating a wide range of immune programs that determine both infection outcome as well as downstream immunopathology. In this review, we discuss the experimental and observational bases for our current understanding of these immune programs, focusing specifically on how the balance of type 1 and type 2 responses governs subsequent immunopathology and clinical outcome.
Portable, battery-operated, fluorescence field microscope for the developing world

In many areas of the world, current methods for diagnosis of infectious diseases such as malaria and tuberculosis involve microscopic evaluation of a patient specimen. Advances in fluorescence microscopy can improve diagnostic sensitivity and reduce time and expertise necessary to interpret diagnostic results. However, modern research-grade microscopes are neither available nor appropriate for use in many settings in the developing world. To address this need, we designed, fabricated, and tested a portable, battery-powered, bright field and fluorescence inverted field microscope, optimized for infrastructural constraints of the developing world. We characterized an initial prototype constructed with rapidprototyping techniques, which utilized low-cost, over-the-counter components such as a battery-powered LED flashlight as the light source. The microscope exhibited suitable spatial resolution (0.8 μm) in fluorescence mode to resolve M. tuberculosis bacilli. In bright field mode, malaria parasites were resolvable at 1000x magnification. The initial prototype cost 480 USD and we estimate that the microscope can be manufactured for 230 USD. While future studies are planned to evaluate ease-of-use and reliability, our current system serves as a proof of concept that combined fluorescence and bright field microscopy is possible in a low-cost and portable system.
Related disorders of bone

Renal osteodystrophy includes a broad spectrum of abnormalities in bone and mineral metabolism. This review article discusses related bone disorders, including calcific uremic arteriolopathy, “osteoporosis” and compromised bone strength, and dialysis-related amyloidosis, as well as the contributing roles of glucocorticoids and metabolic acidosis. Bone disorders in the setting of renal transplantation, including osteoporosis, osteonecrosis, and presistent hyperparathyroidism, are also reviewed.
Obesity and related risk factors in gastric cardia adenocarcinoma

Over recent decades, the incidence of cancers of the gastroesophageal junction, including gastric cardia tumors, has increased markedly. This is a trend that has been well documented, especially in studies from the USA and northern Europe that have also demonstrated a concomitant rise in the ratio of cardia to distal gastric cancers. The rise in the prevalence of gastric cardia adenocarcinoma has been paralleled by the worldwide obesity epidemic, with almost all epidemiological studies reporting increased body mass index and obesity increase the risk of cardia cancer development. However, the strength of this association is less marked than the link between obesity and esophageal adenocarcinoma, and the mechanisms remain poorly understood. Other possible confounders of the relationship between obesity and cardia cancer include the decline in Helicobacter pylori infection and the widespread use of proton pump inhibitors, although these have rarely been controlled for in case-control and cohort studies investigating associations between obesity and cardia cancer. We review these epidemiological trends and discuss proposed mechanisms for the association, drawing attention to controversies over the difficulty of defining cardia cancer. The relative paucity of high-quality epidemiological studies from other regions of the world should prompt further investigation of this issue, especially in populations undergoing rapid socioeconomic change.
Reference-Free Nonuniformity Compensation For IR Imaging Arrays

Multi-detector IR imaging focal plane arrays possess large detector-to-detector dark current (offset) and responsivity (gain) variations which can completely mask the useful thermal signatures in IR scenes. Conventional detector compensation techniques require uniform temperature references of constant radiance over the entire field of view and a mechanical/ electro-optical shutter. This detracts from the mechanical simplicity of multi-detector staring focal planes (which require no scanning). This paper describes a real-time offset and responsivity (gain) compensation technique which dispenses with temperature references and shutters in staring focal planes. The technique makes use of the IR scene itself for calibration and continuously updates the compensation coefficients without interrupting the field of view with a shutter or a temperature reference. The results of real-time simulations of this technique with a number of sensors are presented. Real-time hardware implementation considerations suggest that the technique can be implemented with the addition of very little hardware to a conventional compensation technique requiring temperature references. The technique is also suitable for multi-detector scanning focal planes and for the removal of shading in TV sensors as well.
Admixture and recombination among Toxoplasma gondii lineages explain global genome diversity

Toxoplasma gondii is a highly successful protozoan parasite that infects all warm-blooded animals and causes severe disease in immunocompromised and immune-naive humans. It has an unusual global population structure: In North America and Europe, isolated strains fall predominantly into four largely clonal lineages, but in South America there is great genetic diversity and the North American clonal lineages are rarely found. Genetic variation between Toxoplasma strains determines differences in virulence, modulation of host-signaling pathways, growth, dissemination, and disease severity in mice and likely in humans. Most studies on Toxoplasma genetic variation have focused on either a few loci in many strains or low-resolution genome analysis of three clonal lineages. We use whole-genome sequencing to identify a large number of SNPs between 10 Toxoplasma strains from Europe and North and South America. These were used to identify haplotype blocks (genomic regions) shared between strains and construct a Toxoplasma haplotype map. Additional SNP analysis of RNA-sequencing data of 26 Toxoplasma strains, representing global diversity, allowed us to construct a comprehensive genealogy for Toxoplasma gondii that incorporates sexual recombination. These data show that most current isolates are recent recombinants and cannot be easily grouped into a limited number of haplogroups. A complex picture emerges in which some genomic regions have not been recently exchanged between any strains, and others recently spread from one strain to many others.
Nurses' knowledge of pain management for patients with combat-related traumatic brain injuries on rehabilitation units.

Purpose The purpose of this project was to survey nurses' knowledge of pain management for patients with combat-related traumatic brain injuries (TBI). Design/Methods A survey was used to collect data regarding nurses' knowledge of pain assessment and management for patients with combat-related TBI. Nurses were invited to participate in the study via email and provided with a link to the electronic survey. Findings Twenty-five surveys were returned (52% response rate). A total of 76% of nurse respondents perceived that TBI patients over report pain intensity. Only 40% of nurses were able to correctly identify the appropriate medication to treat migraine-type headache pain in TBI patients. Conclusion This study identified gaps in knowledge regarding pain management for patients with combat related TBIs. Clinical Relevance Nurses need additional education regarding common pain syndromes, available treatments, and a better understanding of addiction in order to provide optimal care to these patients.
Estimation of CO2 Production in Enterally Fed Preterm Infants Using an Isotope Dilution Stable Tracer Technique

Background: Estimates of the rate of Co 2 production may be useful in preterm infants, but assessment of the rate of respiratory excretion of CO 2 (Vco 2 ) may not always be practical in infants requiring constant care. We hypothesized that the rate of dilution of 13 CO 2 (Raco 2 ) would be a valid index of CO 2 production in preterm infants. Methods: Twelve studies of Raco 2 and Vco 2 were performed in six enterally fed preterm infants. Raco 2 was measured using a 2-hour, primed, constant, orogastric infusion of NaH 13 CO 3 with formula and an assessment of the plateau 13 C enrichment of expired CO 2 . VCO 2 was measured over two 10-minute intervals during the infusion using a flow-through system. Energy expenditure was estimated from these data and the food quotient. Results: Mean (± SD) rate of CO 2 production using RaCO 2 (348 ± 32 μmol/kg/min) was 114% of that estimated usingVco 2 (304 ± 51 μmol/kg/min). The ratio of Vco 2 /Raco 2 is equal to the fractional recovery of tracer CO 2 in the expired air during the course of the tracer infusion. In studies of short duration, this ratio is generally less than 100% because of isotope exchange. For five pairs of studies performed on consecutive days, each individual value of Raco 2 on day 2 was multiplied by the mean of the individual ratios of Vco 2 /Raco 2 on day 1 (0.78); corrected Raco 2 was 306 ± 19 μmol/kg/min compared with 307 ± 59 μmol/kg/min for Vco 2 . Conclusions: Thus, Raco 2 , particularly when corrected for isotope recovery, may be a useful index of group mean CO 2 production and energy expenditure in preterm infants.
Bcl3 regulates pro-survival and pro-inflammatory gene expression in cutaneous T-cell lymphoma

The advanced stages of cutaneous T cell lymphoma (CTCL) are characterized not only by decreased levels of pro-inflammatory cytokines, resulting in high susceptibility to infections, but also by high constitutive activity of NFκB, which promotes cell survival and resistance to apoptosis. The increased expression of the proto-oncogene Bcl3 belonging to IκB family is associated with the pathogenesis of the different types of human cancer, yet, the function and regulation of Bcl3 in CTCL have not been studied. Here, we show that Bcl3 is highly expressed in CTCL Hut-78 and HH cells. The suppression of Bcl3 levels decreases the expression of the pro-survival genes cIAP1 and cIAP2, reduces cell viability, and increases CTCL apoptosis. Interestingly, Bcl3 suppression concomitantly increases expression and the release of the pro-inflammatory cytokines IL-8 and IL-17 in CTCL cells. Chromatin immunoprecipitation studies show that Bcl3 regulates cIAP1, cIAP2, IL-8 and IL-17 gene expression through direct binding to their promoters. Bcl3 expression is regulated by bortezomib (BZ)-mediated proteasome inhibition, and BZ inhibits Bcl3 recruitment to its target promoters, resulting in decreased expression of cIAP1 and cIAP2, but increased expression of IL-8 and IL-17. The Bcl3 expression is regulated through NFκB subunit exchange on Bcl3 promoter. In untreated cells, the Bcl3 promoter is occupied predominantly by p65/p50 heterodimers, inducing Bcl3 expression; however, in BZ-treated cells, the p65/50 heterodimers are replaced by p52 subunits, resulting in Bcl3 transcriptional repression. These data provide the first insights into the function and regulation of Bcl3 in CTCL, and indicate that Bcl3 has an important pro-survival and immunosuppressive role in these cells.
Assessment of fetal canine cardiac myocyte survival in a dual‐side flow bioreactor with modeled hypoxia/reperfusion injury

The present study introduces a new experimental model of hypoxia/reperfusion injury using a newly developed bioreactor system. The injury is introduced and kept localized via fluid dynamic manipulation. Using low Reynolds number fluid flow, regions of the culture can be injured while maintaining physiological conditions in the remaining culture. This approach enables both normal and injured cells within the same monolayer to be investigated side-by-side. The current study evaluated the ability of the model to induce localized reperfusion injury in a monolayer of fetal canine cardiomyocytes (FCCs). Significant apoptosis was found in the hypoxia/reperfusion-injured but not normal-flow regions of the myocyte cultures. The model holds the potential to help elucidate the fundamental mechanisms of hypoxic/reperfusion insults in myocardium.
Biliary cast syndrome following liver transplantation: Predictive factors and clinical outcomes†

Biliary cast syndrome (BCS), the presence of biliary casts and debris causing biliary obstruction, occurs in 4%-18% of orthotopic liver transplant (OLT) recipients. Potential consequences include cholangitis and graft damage or loss. Limited data exist regarding the etiology and outcomes of BCS. The purpose of this study was to evaluate donor and recipient risk factors and determine the impact of BCS. A retrospective review of 355 OLT cases identified 9 BCS patients (2.5%) diagnosed by cholangiography. Twenty-six matched controls were also identified. The warm ischemic time was significantly longer in BCS patients. Other recipient and donor preoperative and intraoperative characteristics, including the donor risk index, revealed no significant differences. Overall patient survival showed a trend toward worse outcomes at 6, 12, and 18 months and end of follow-up in the BCS group. Overall graft survival was also worse in the BCS group at all time periods, with statistical significance demonstrated at 18 months and end of follow-up. The number of therapeutic biliary procedures and hospital readmissions was significantly higher in the BCS group. Twenty-two percent of the BCS patients required repeat OLT versus none of the control patients. In conclusion, BCS is an uncommon complication of OLT. Except for a longer warm ischemic time, recipient and donor factors did not predict the occurrence of BCS. BCS patients showed a significantly worse graft survival, as well as a trend toward worse patient survival. Given the negative impact of BCS on liver transplant outcomes, further studies appear justified.
Annual and semi-annual anthropogenic sulfur budget for Eastern North America

Abstract A balance of sulfur emissions with deposition and effluxes in eastern North America is obtained for both annual and semi-annual periods using a previously reported regional transport model. Of the total regional sulfur emissions, 60% is deposited (wet and dry) and 40% flows out of the region. U.S.A. sulfur transboundary export to Canada is eight times the reverse flow. The respective transboundary flows are apportioned among the states and provinces.
Comparison of intravenous immune globulin and high dose anti‐D immune globulin as initial therapy for childhood immune thrombocytopenic purpura

Summary This report documents our experience with intravenous immune globulin (IVIG) (1 g/kg, iv) and high-dose, anti-D immune globulin (anti-D) (75 μg/kg) as initial treatment for childhood immune thrombocytopenic purpura (ITP). The medical records of children diagnosed with ITP at a single institution between January 2003 and May 2008 were retrospectively reviewed. Participants received either IVIG or high-dose anti-D immune globulin as their initial treatment for ITP. For the 53 patients included for analysis, there was no statistical difference in efficacy between each group; however, patients who received anti-D experienced a higher rate of adverse drug reactions (ADRs), particularly chills and rigours, and 2 of 24 patients in the anti-D group developed severe anaemia requiring medical intervention. Patients who presented with mucosal bleeding had higher rates of treatment failure (32%) compared to those who presented with dry purpura (6%), regardless of treatment. Both IVIG and high-dose anti-D are effective first-line therapies for childhood ITP. However, we observed increased ADRs in the high-dose anti-D group in contrast to previously published reports. Further studies are needed to evaluate safety and premedications for high-dose anti-D and to determine the utility of using the presence of mucosal bleeding to predict treatment failure.
Modulation of Na+, Cl- and HCO3- transport by carbachol in pig distal jejunum.

Abstract Acetylcholine and cholinomimetics such as carbachol are potent stimulants of epithelial Cl − secretion in the small and large intestines of several mammalian species. In this study, the effects of carbachol were characterized in vitro on active ion transport in sheets of submucosa-mucosa from the distal jejunum of swine. Carbachol (10 μM) produced an increase in serosa-positive short-circuit current (Isc) in this tissue after its serosal, but not luminal administration. The Na + -K + -Cl − transport blocker bumetanide (10 μM) produced a 50% decrease in the carbachol-induced Isc elevation after its serosal administration. Peak increases in Isc evoked by carbachol were significantly reduced by 60–85% in tissues bathed in media lacking Cl − , HCO 3 − , or both anions. The initial drug-induced increase in net charge transfer from serosa to lumen was dependent upon both HCO 3 − and Cl − , whereas sustained elevations in charge transfer were dependent upon extracellular Cl − only. Radiotracer flux analyses revealed that the drug decreased net Na + absorption and increased Cl − secretion. In the absence of HCO 3 − , carbachol decreased Cl − absorption. The effects of carbachol on HCO 3 − transport were examined by pH-stat titration. The drug rapidly alkalinized the luminal medium immediately after its serosal administration. These results suggest that carbachol stimulates electrogenic anion secretion in the mucosa of the porcine distal jejunum. Furthermore, the ability of carbachol to inhibit spontaneous Na + absorption is dependent upon extracellular HCO 3 − .
Sexual functioning in adolescents and young adults with spina bifida.

Abstract Cardenas DD, Topolski TD, White CJ, McLaughlin JF, Walker WO. Sexual functioning in adolescents and young adults with spina bifida. Objective To assess sexual education and sexual functioning in adolescents and young adults with spina bifida. Design Survey, inception cohort. Setting The community. Participants A cohort of adolescents and young adults (N=121; range, 15–35y; 58% women) enrolled in a longitudinal pediatric database. Interventions Not applicable. Main Outcome Measures Questions on sexual function, reproductive function, bladder and bowel continence, the Perceived Quality of Life Scale, and the Satisfaction With Life Scale. Results Almost all adolescents and young adults with spina bifida in our study received sexual education at school, less at home, or by physicians. Twenty-five percent of men and 68% of women were informed about reproductive function by their physicians. Participants who reported that they smoked were 10 times more likely to report being sexually active and women were 2.3 times more likely to be sexually active than men. Hydrocephalus was a significant predictor of sexual activity among women but not men. Participants with urinary incontinence were less likely to be sexually active. Women without hydrocephalus were significantly more satisfied with life than women with hydrocephalus. Conclusions Adolescents and young adults with spina bifida in this sample were only slightly satisfied with life and sexual activity was only associated with life satisfaction among women. Dissatisfaction with life often leads to engagement in health-risk behaviors, which may, in part, account for the association between sexual activity and smoking behavior observed in these data. Further studies of health risk behaviors among youth with spina bifida are warranted and interventions aimed at reducing health risk behaviors among adolescents and young adults should specifically include spina bifida as a target group.
Noise-induced eating in rats facilitated by prior tail pinch experience

In order to integrate the results of procedures that induce excessive nonregulatory eating, it is necessary to develop new procedures that elicit eating in satiated animals. To that end, the present study examined the effects of 90-dB white noise on eating in satiated rats. Twenty-four rats, including sixteen with prior tail pinch-induced eating experience, were presented with mash in baseline and noise conditions. Whereas white noise induced eating in tail pinch-experienced rats, noise did not do so in naive subjects. It was concluded that experience with eating in response to arousal increased the likelihood that an animal would respond to a different kind of arousal by eating.
Dihapto coordination of carboxylic acid derivatives with an asymmetric rhenium π-base: A new mechanism for amide isomerization?

The asymmetric π basic metal fragment {TpRe(CO)(MeIm)} (Tp = hydridotris(pyrazolyl)borate, MeIm = 1-methylimidazole) forms thermally stable complexes with ethyl acetate, acetic anhydride, N-methylsuccinimide, N-acetylpyrrole, and N-methylmaleimide in which the metal binds a carbonyl group in a π fashion. In all cases a single diastereomer is observed, indicating that one enantioface of the carbonyl is selectively coordinated. X-ray and NMR data for the compound TpRe(CO)(MeIm)(η2-N-methylsuccinimide) indicate that metal coordination effectively removes the π interaction between the bound carbonyl and the nitrogen of the succinimide ring.
Dual-energy imaging of bone marrow edema on a dedicated multi-source cone-beam CT system for the extremities

Purpose: Arthritis and bone trauma are often accompanied by bone marrow edema (BME). BME is challenging to detect in CT due to the overlaying trabecular structure but can be visualized using dual-energy (DE) techniques to discriminate water and fat. We investigate the feasibility of DE imaging of BME on a dedicated flat-panel detector (FPD) extremities cone-beam CT (CBCT) with a unique x-ray tube with three longitudinally mounted sources. Methods: Simulations involved a digital BME knee phantom imaged with a 60 kVp low-energy beam (LE) and 105 kVp high-energy beam (HE) (+0.25 mm Ag filter). Experiments were also performed on a test-bench with a Varian 4030CB FPD using the same beam energies as the simulation study. A three-source configuration was implemented with x-ray sources distributed along the longitudinal axis and DE CBCT acquisition in which the superior and inferior sources operate at HE (and collect half of the projection angles each) and the central source operates at LE. Three-source DE CBCT was compared to a double-scan, single-source orbit. Experiments were performed with a wrist phantom containing a 50 mg/ml densitometry insert submerged in alcohol (simulating fat) with drilled trabeculae down to ~1 mm to emulate the trabecular matrix. Reconstruction-based three-material decomposition of fat, soft tissue, and bone was performed. Results: For a low-dose scan (36 mAs in the HE and LE data), DE CBCT achieved combined accuracy of ~0.80 for a pattern of BME spherical lesions ranging 2.5 - 10 mm diameter in the knee phantom. The accuracy increased to ~0.90 for a 360 mAs scan. Excellent DE discrimination of the base materials was achieved in the experiments. Approximately 80% of the alcohol (fat) voxels in the trabecular phantom was properly identified both for single and 3-source acquisitions, indicating the ability to detect edemous tissue (water-equivalent plastic in the body of the densitometry insert) from the fat inside the trabecular matrix (emulating normal trabecular bone with significant fraction of yellow marrow). Conclusion: Detection of BME and quantification of water and fat content were achieved in extremities DE CBCT with a longitudinal configuration of sources providing DE imaging in a single gantry rotation. The findings support the development of DE imaging capability for CBCT of the extremities in areas conventionally in the domain of MRI.
Racial differences in the management of unstable angina: results from the multicenter GUARANTEE registry.

Abstract Background Prior studies, usually conducted with the use of insurance databases, have shown differences in the use of cardiac procedures between black patients and white patients hospitalized with various types of coronary artery disease. However, few data are available in prospectively collected cohorts of patients with unstable angina or on the use of appropriate medications or interventions. Methods and Results We evaluated 2948 consecutive patients with unstable angina admitted to 35 hospitals across the United States in 1996, comparing nonwhite and white patients. Seventy-seven percent of patients were white, 14% were black, 4% were Hispanic, 1% were Asian, and 3% were other or unknown race. Differences were seen in coronary risk profile, with a higher incidence of hypertension and diabetes mellitus in nonwhites. Cardiac catheterization was performed less often in nonwhites compared with whites (36% vs 53%, P = .001). Even in patients meeting the criteria for appropriate catheterization in the Agency for Health Care Policy Research unstable angina guidelines, fewer nonwhites underwent catheterization (44% vs 61%, P = .001), but among these, fewer nonwhites had significant coronary stenosis (72% vs 90%, P = .001). However, among patients catheterized who had indications for revascularization, angioplasty and coronary artery bypass grafting were performed equally often in nonwhites and whites. Conclusions Current guidelines would recommend more aggressive use of cardiac catheterization for nonwhite patients. However, our findings suggest that racial differences may need to be included in the diagnostic and interventional algorithms. (Am Heart J 1999;138:1065-72.)
Free-free electron scattering from a model atom: Comparison of one- versus Two-photon absorption and Test of the Soft-photon Approximation

We have calculated the cross sections for one- and two-photon absorption by an electron scattering from the Kr\"uger-Schulz model atom in the presence of a low-frequency (linearly or circularly polarized) laser. Let $\ensuremath{\xi}\ensuremath{\equiv}\frac{e{A}_{0}(\stackrel{^}{\ensuremath{\epsilon}}\ifmmode\cdot\else\textperiodcentered\fi{}\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\Delta}})}{(mc\ensuremath{\omega})}$, where ${A}_{0}$, $\stackrel{^}{\ensuremath{\epsilon}}$ and $\ensuremath{\omega}$ are the amplitude, polarization, and frequency of the laser field, and where $\ensuremath{\hbar}\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\Delta}}$ is the momentum transfer to the electron of mass $m$ and charge $e$. If $|\ensuremath{\xi}|\ensuremath{\lesssim}1$, one-photon dominates over two-photon absorption except perhaps over some range of angles, and except over a range of energies near a resonance. We examined in detail the applicability of the soft-photon approximation.
Comparison of liquid chromatographic selectivity for polycyclic aromatic hydrocarbons on cyclodextrin and C18 bonded phases

Abstract Selectivity towards polycyclic aromatic hydrocarbons (PAHs) was studied on cyclodextrin bonded phases and compared to selectivity observed on C 18 phases. The study included the separation of eleven five-ring PAH isomers on each of three phase types; monomeric C 18 , polymeric C 18 and cyclodextrin. Retention of PAHs ranging in size from three to six condensed rings was also investigated. Retention on the cyclodextrin phase is based on inclusion complexing between the solute and cyclodextrin cavity, resulting in a strong shape dependence. However, the shape selectivity exhibited by the cyclodextrin phase is different from that exhibited by either the monomeric or polymeric C 18 phases; retention on the cyclodextrin phase is strongly dependent on the shape and shows very little molecular weight dependence. Calculations of solute molecular widths were performed to predict the isomers' ability to enter the cyclodextrin cavity. The effect of sample solvent and injection volume was also investigated for the cyclodextrin phase. A retention model based on the solute shape is proposed for PAH isomers on β-cyclodextrin phase.
Concepts: An epistemological justification for the role of teaching in distance education

(1988). Concepts: An epistemological justification for the role of teaching in distance education. American Journal of Distance Education: Vol. 2, No. 3, pp. 5-16.
Configurations of a polymeric antigen adsorbed to a B-cell membrane

Abstract Thymus-independent antigens that can stimulate B cells in the absence of T cells are polymeric molecules with repeating arrays of antigenic determinants. Immunological studies of the activity of haptenated thymus-independent antigens have shown that small changes in hapten density can transform a polymeric antigen from non-immunogenic to immunogenic, and from immunogenic to tolerogenic. Such studies seem to indicate that the structure of the polymer, when bound to a B cell, is important in determining immunological responses. In this paper we compute the equilibrium configuration of a linear, haptenated polymer adsorbed to a cell surface, and correlate configurational features of the molecule with its immunological functioning. When a polymeric molecule is bound to a cell the whole molecule is not tied to the surface; rather there are sections which form loops extending into solution, and other sections, trains , which are bound tightly to the surface. The trains cross-link antibody receptors on the B-cell surface in a fashion which restricts their mobility in the plane of the membrane. We call this type of cross-linking restrictive . Our computation of equilibrium polymer configurations shows that there is a critical hapten density, below which the polymer does not bind to the surface. At hapten densities slightly above the critical density, the polymer binds weakly to the surface with a configuration dominated by few, rather long loops. These loops cross-link receptors, but do so without bringing the cross-linked receptors into close proximity and without substantially restricting their motion. Long loops thus cause unrestrictive cross-linking. As the hapten density increases, the average loop length decreases and the average train length increases. Thus cross-linking becomes restrictive. In this density range immune stimulation is observed. At high hapten densities long trains form, separated by few, very short loops and almost all receptors are cross-linked. Consequently cross-linking may be overly restrictive , freezing receptors into place and generating an abundance of cross-linking or other signals which induce a state of immunological tolerance.
Molecular-dynamics study of elasticity and failure of ideal solids

Results are presented from molecular-dynamics simulations of ideal solids under conditions of constant temperature, pressure, and uniaxial tensile force. We show that the system remains in metastable equilibrium all the way up to a critical value of the applied stress or force, at which point it fails irreversibly via the nucleation of small-scale defects. The critical load (failure strength) is found to decrease strongly with temperature.
Development and analysis of a feedback treatment strategy for parturient paresis of cows

An intelligent on-line feedback treatment strategy based on nonlinear optimal control theory is presented for the parturient paresis of cows. A limitation in the development of an existing nonlinear mathematical model for the homogeneous system is addressed and further modified to incorporate a control input. A neural network based optimal feedback controller is synthesized for the treatment of the disease. Detailed studies are used to analyze the effectiveness of a feedback medication strategy and it is compared with the current 'impulse' strategy. The results show that while the current practice may fail in some cases, especially if it is carried out before the condition of a patient deteriorates, the proposed continuous medication process may be initiated at any time. Moreover the proposed on-line continuous infusion strategy never leads to severe hypercalcemic problems, thereby avoiding an associated disastrous consequence of cardiac arrest. A comparison study with linear quadratic regulator theory brings out the advantages of the nonlinear control synthesis approach.
Disability Research: Progress Made, Opportunities for Even Greater Gains

Although disability is a complex phenomenon, the articles in this special issue illustrate that we are making considerable progress in the ability to conceptualize, measure, predict, and intervene to change disability. Conceptual models such as the International Classification of Function, Disability and Health (ICF)1 have greatly aided our understanding of disability and our ability to investigate it using different research designs. The ICF describes the many factors that may contribute to disability or participation restriction, including impairments, activity limitations, and environmental and personal factors. Physical therapy research traditionally has focused on the impairment end of the ICF model. However, this special issue contains many articles that reflect the growing recognition of the importance of the other domains in the ICF. For instance, several articles in this issue focus on the impact that personal factors, such as self-efficacy and other psychological attributes, have on participation. Robinson et al2 explored participation in community walking by survivors of stroke. They found that balance self-efficacy was the single factor that was most strongly associated with differences in measurements of participation. In people with Parkinson disease, Ellis et al3 found that exercise self-efficacy was the major predictor of participation in physical activity. In fact, self-efficacy was much more predictive than other factors—such as disease severity, impairments, and functional limitations—that might have been expected to influence exercise participation in people with Parkinson disease. Two studies highlighted the complexity of identifying the factors that contribute to disability in people with painful conditions. Hart and colleagues4 explored the role that psychosocial variables play in functional status changes in people receiving outpatient physical therapy services for lumbar spine syndromes. This study found that psychosocial factors, in particular fear-avoidance behavior, were significant predictors of functional status outcomes. In a large observational cohort study, White …
Crystallization of Stoichiometric SbSI Glass

Congruent crystallization of antimony sulphoiodide (SbSI) glass of stoichiometric composition, which is prepared successfully for the first time using rapid melt-quenching, has been investigated using differential scanning calorimetry (DSC). The results for glass powder show a glass transition at 127°C and two separate exothermal peaks with maxima around 140°C and 190°C. The ratio of the intensities of the exothermal peak at ~190°C to the peak at ~140°C increases as the particle size and heating rate are increased, but their total enthalpy remains constant at 62 ± 2 J/g for all DSC runs. Surface heating of the glass induced by a 520 nm CW laser shows two contracted regions: needle-like crystalline formations at low temperature and bulk crystallization at high temperature. The observed phenomena and DSC results suggest two different kinds of crystallization of the SbSI phase: one-dimensional crystallization at low temperature which starts from the sample surface and three-dimensional bulk crystallization that continues the transformation to crystalline state at higher temperatures. The origin of the two different crystallizations can be traced to the strong anisotropy of the SbSI crystal structure due to the weak van der Waals interaction between covalent-ionic chains (Sb2S2I2)n.
Application of neural networks to nonlinear dynamical systems

We use the multilayer perceptron and the functional link net to implement the nonlinearities. Our simulations show that these neural network controllers have a great advantage over the conventional feedback controller. We also discuss the application of these types of neural network used in time varying systems. >
Enhanced mobile security using SIM encryption

Mobile security is a main topic of concern for the enterprise. Corporate data stored in employees device post a potential security risk of getting lost, stolen or get accessed by unauthorized personal. There are many solutions in the market that addresses this issue. Most of these solutions revolve around applying stronger password, others make use of the encryption of either full or partial hard drive. Data encryption for mobile devices is a known art. However, the existing mobile data encryption solutions share the same methodology with slight implementation variation. The common techniques used to secure mobile data and or mobile code is wither on the application layer using software encryption or on the hardware layer. Our proposed solution introduces a new approach for securing data in mobile devices with encryption technique that is integrated with the mobile SIM card and robust enough to accommodate the common use case of mobile upgrade and yet keep corporate data encrypted.
Optimal Rate and Power Allocation for Layered Transmission with Superposition Coding

The problem of transmitting an analog source over a quasi-static fading channel is considered. This problem is motivated by the recent demand for multimedia content over wireless channels. The goal is to minimize the expected distortion of the received signal. An efficient numerical technique is proposed to explicitly solve the rate and power allocation problems at a finite SNR. The proposed algorithm iteratively optimizes the rates for a given power allocation and vice versa, and is guaranteed to converge
Neurofeedback of two motor functions using supervised learning-based real-time functional magnetic resonance imaging

This study examines the effects of neurofeedback provided by support vector machine (SVM) classification-based real-time functional magnetic resonance imaging (rt-fMRI) during two types of motor tasks. This approach also enables the examination of the neural regions associated with predicting mental states in different domains of motor control, which is critical to further our understanding of normal and impaired function. Healthy volunteers (n = 3D13) performed both a simple button tapping task, and a covert rate-of-speech counting task. The average prediction accuracy was approximately 95% for the button tapping task and 86% for the speech task. However, subsequent offline analysis revealed that classification of the initial runs was significantly lower - 75% (p<0.001) for button and 72% (p<0.005) for speech. To explore this effect, a group analysis was performed using the spatial maps derived from the SVM models, which showed significant differences between the two fMRI runs. One possible explanation for the difference in spatial patterns and the asymmetry in the prediction accuracies is that when subjects are actively engaged in the task (i.e. when they are trying to control a computer interface), they are generating stronger BOLD responses in terms of both intensity and spatial extent.
Is ZFY the Sex-Determining Gene on the Human Y Chromosome?

The sex-determining region of the human Y chromosome contains a gene, ZFY, that encodes a zinc-finger protein. ZFY may prove to be the testis-determining factor. There is a closely related gene, ZFX, on the human X chromosome. In most species of placental mammals, we detect two ZFY-related loci: one on the Y chromosome and one on the X chromosome. However, there are four ZFY-homologous loci in mouse: Zfy-1 and Zfy-2 map to the sex-determining region of the mouse Y chromosome, Zfx is on the mouse X chromosome, and a fourth locus is autosomal.
On the performance of a second-order adaptive Volterra filter

The impact of the bias or DC term on the performance of a second-order Volterra least-mean-square (LMS) filter is discussed. Without the DC term the filter may itself produce a biased output. It is shown that including a DC term always degrades adaptive system performance, in terms of both convergence and steady state. Unlike the usual LMS approach, the second-order scheme converges nonuniformly, even with white inputs. For deterministic signals an approximate transfer function descriptor is obtained for the second-order LMS filter. Jury (1964) tables are used to obtain explicit stability conditions. >