cssi/SciSciGPT-SciSciNet huggingface dataset:
In vitro and in vivo mechanical properties of human ulnar and median nerves

Peripheral nerves are often subjected to mechanical stretching, which in excess results in various degrees of impairment of their function. An understanding of the biomechanical behavior of peripheral nerves is important to the prevention of nerve injury during surgical manipulation. Here, in vitro mechanical properties and viscoelastic behavior of human ulnar/median nerves were measured with a tensile tester. In vivo stress and deformation of an ulnar nerve was also examined in continuity during a surgical procedure. Finite element models were developed to determine in vitro and in vivo viscoelastic parameters of the nerves. The results show that in vitro mechanical properties of fresh ulnar nerve are different from those measured in vivo. Several factors that are possibly attributed to the difference were analyzed. The in situ strain of the nerves is one of the major factors that must be considered to obtain accurate strain-stress relationship in the in vivo measurement.
Usability evaluation of a flight-deck airflow hazard visualization system

Many aircraft accidents each year are caused by encounters with unseen airflow hazards near the ground, such as vortices, downdrafts, low level wind shear, microbursts, or turbulence from surrounding vegetation or structures near the landing site. These hazards can be dangerous even to airliners; there have been hundreds of fatalities in the United States in the last two decades attributable to airliner encounters with microbursts and low level wind shear alone. However, helicopters are especially vulnerable to airflow hazards because they often have to operate in confined spaces and under operationally stressful conditions (such as emergency search and rescue, military or shipboard operations). Providing helicopter pilots with an augmented-reality display visualizing local airflow hazards may be of significant benefit. However, the form such a visualization might take, and whether it does indeed provide a benefit, had not been studied before our experiment. We recruited experienced military and civilian helicopter pilots for a preliminary usability study to evaluate a prototype augmented-reality visualization system. The study had two goals: first, to assess the efficacy of presenting airflow data in flight; and second, to obtain expert feedback on sample presentations of hazard indicators to refine our design choices. The study addressed the optimal way to provide critical safety information to the pilot, what level of detail to provide, whether to display specific aerodynamic causes or potential effects only, and how to safely and effectively shift the locus of attention during a high-workload task. Three-dimensional visual cues, with varying shape, color, transparency, texture, depth cueing, and use of motion, depicting regions of hazardous airflow, were developed and presented to the pilots. The study results indicated that such a visualization system could be of significant value in improving safety during critical takeoff and landing operations, and also gave clear indications of the best design choices in producing the hazard visual cues.
Aversion to injection limits acceptability of extended-release naltrexone among homeless, alcohol-dependent patients.

ABSTRACT Background: Ending homelessness is a major priority of the Department of Veteran Affairs (VA), and alcohol use can be a barrier to stable housing. Clinical trials suggest that depot extended-release naltrexone (XR-NTX) is efficacious in reducing alcohol consumption among alcohol-dependent subjects. Methods: An open-label, randomized pilot study sought to examine the feasibility and effectiveness of XR-NTX versus oral naltrexone to improve alcohol consumption and housing stability among homeless, alcohol-dependent veterans at the Providence Veteran Affairs Medical Center. Results: Of 215 potential candidates approached over a 16-month recruitment period, only 15 agreed to consider study entry and 7 were randomized. The primary reasons given for refusal were not wanting an injection; fear of needles; and not wanting to change drinking habits. Only 1 participant in the XR-NTX group returned after the first injection. Three participants in the oral naltrexone group attended all 7 visits and had good ...
CMOS-MEMS novel resonator for filter tuning

Novel MEMS resonators are presented in this work, and were designed in CMOS process. The devices were fabricated and tested. The work shows the combined CMOS and MEMS process. The resonators are designed in Fixed -Fixed beam structure. Applications are low power temperature tuning filters, and temperature sensors.
Electronic Reverse Auctions - Success Metrics & Dynamics

This paper describes an on-going study analyzing thousands of electronic procurement auctions conducted by a large multinational firm. We describe the challenges of developing metrics for auction success and auction dynamics and how these metrics improve our ability to model, understand, and manage this domain. Since we are in the initial stages of our study and since many of our findings are confidential, this paper is limited to describing the metrics and the relationships investigated between supplier experience, supplier participation levels, late bidding behavior, and electronic reverse auction success. By the time of the presentation, we expect to obtain permission to reveal more details about our findings.
The Forcing of Monthly Precipitation Variability over Southwest Asia during the Boreal Cold Season

AbstractSouthwest Asia, defined as the region containing the countries of Afghanistan, Iran, Iraq, and Pakistan, is water scarce and receives nearly 75% of its annual rainfall during the boreal cold season of November–April. The forcing of southwest Asia precipitation has been previously examined for the entire boreal cold season from the perspective of climate variability originating over the Atlantic and tropical Indo-Pacific Oceans. This study examines the intermonthly differences in precipitation variability over southwest Asia and the atmospheric conditions directly responsible in forcing monthly November–April precipitation.Seasonally averaged November–April precipitation over southwest Asia is significantly correlated with sea surface temperature (SST) patterns consistent with Pacific decadal variability (PDV), El Nino–Southern Oscillation (ENSO), and the long-term change of global SST (LT). In contrast, the precipitation variability during the individual months of November–April is unrelated and i...
Real-time billing throughput analysis of wireless telecommunication systems

Real-time billing is one of the most important functionalities in a telecommunication service system. In GPRS network, the load of billing traffic depends on the load of call traffic and the size of billing records. During busy hours, the GPRS network might not be able to transfer billing records on a timely basis if new billing records are generated too fast. This paper considers the capacity of the billing record collection and transfer system of the GPRS network. Stochastic timed Petri nets are employed to establish a template for the analysis of the capacity versus various factors.
Positron emission tomography with 2-deoxy-2-[18F]fluoro-D-glucose for evaluating local and distant disease in patients with cervical cancer

Abstract Purpose To assess the accuracy of positron emission tomography (PET) with 2-deoxy-2-[18F]fluoro-D-glucose (FDG) for evaluating local and distant disease in patients with cervical cancer. Methods The PET imaging database maintained at our institution was used to identify patients who received FDG-PET scans for the clinical indication of cervical cancer for the past four years. Patients were followed for a minimum of six months following the PET study. Results of the FDG-PET studies were correlated with surgical pathology, biopsy results, and/or clinical follow up to assess the accuracy of FDG-PET in evaluating local and distant disease. Results A total of 61 FDG-PET studies performed in 41 patients were included in this retrospective study. Nine FDG-PET studies were performed for initial staging of cervical cancer, and 52 PET scans were performed in 35 different patients as restaging studies following therapy. For the initial staging, the local primary disease was identified in all nine FDG-PET studies, and PET distinguished the patients which had localized disease (four patients) from those with distant metastases on follow-up (five patients) with 100% accuracy. For restaging cervical cancer, FDG-PET had a sensitivity of 0.82 and specificity of 0.97 (accuracy 0.92) for evaluation of local recurrence. For evaluating distant disease in these patients, PET had a sensitivity of 1.00 and specificity of 0.90 (accuracy 0.94). In the evaluation of local disease, focal rectal activity caused false-positive results in two cases. Three false-positive studies for distant disease were caused by inflammatory adenopathy. Conclusion FDG-PET is an accurate modality both for initial staging and restaging of patients with cervical cancer. PET is particularly sensitive for detecting distant metastases, allowing stratification of patients into those with locally confined disease and those with distant disease. These results were achieved by using a standardized PET imaging protocol without the use of bowel preparations, lasix administration, or Foley catheter drainage. Evaluation of local disease can be challenging due to adjacent rectal and bladder activity, and the use of hybrid PET/computed tomography (CT) scanners in the future may further improve evaluation of local disease.
Vimentin gene expression during myogenesis: two functional transcripts from a single copy gene

Abstract We have previously reported that a single vimentin gene is present in the chicken genome (22). In vivo transcription of this gene yields two distinct classes of mRNA's (approximatley 2200 and-2500 nts) generated through the possible differential utilization of polyadenylylation sites. In this report we demonstrate that 1) both transcripts are functional in vitro and direct the cell-free synthesis of the vimentin polypeptide, as judged by two dimensional gel analysis; 2) three of the four possible adenylylation signals indicated in the sequence of the gene are utilized in vivo as determined by S1 analysis; 3) furthermore, these adenylylation sites are utilized identically in all tissues of the chicken examined; 4) the adenylylation site closest to the body of the message is apparently not used as judged by the S1 conditions employed in the assay. Levels of vimentin mRNA decrease in different tissues of the chicken during the embryonic to adult transition. There is no evidence for a tissue specific or developmentally regulated pattern of expression for either of the two vimentin transcripts. The same pattern of vimentin mRNA expression is seen in all tissues examined, only the level of expression is altered.
Sacroiliac joint dysfunction: evaluation and management.

UNLABELLED Sacroiliac joint dysfunction is believed to be a significant source of low back and posterior pelvic pain. METHODS To assess the clinical presentation, diagnostic testing, and treatment options for sacroiliac joint dysfunction, a systematic literature review was performed using MEDLINE. RESULTS Presently, there are no widely accepted guidelines in the literature for the diagnosis and treatment of sacroiliac instability. Establishing management guidelines for this disorder has been complicated by the large spectrum of different etiologic factors, the variability of patient history and clinical symptoms, limited availability of objective testing, and incomplete understanding of the biomechanics of the sacroiliac joint. CONCLUSIONS A reliable examination technique to identify the sacroiliac joint as a source of low back pain seems to be pain relief following a radiologically guided injection of a local anaesthetic into the sacroiliac joint. Most patients respond to non-operative treatment. Patients who do not respond to non-operative treatment should be considered for operative sacroiliac joint stabilization.
CAN PERINATAL EVENTS CAUSE NEONATAL URINARY ASCITES

A full-term 5,270 gm. male newborn was delivered by a vaginal delivery to a 21-year-old mother (gravida 11, para 0, abortion 1). The prenatal history was unremarkable until the day of delivery when ultrasound revealed massive 11 X 11 cm. right renal hydronephrosis. The ureters and bladder were normal, and there was no ascites. After 12 hours of labor, vaginal delivery was complicated by shoulder dystocia. At birth findings consistent with ascites were noted on physical examination. Abdominal distention and scrotal swelling were present without any palpable masses. Prompt abdominal ultrasound confirmed ascites (fig. 1) with massive hydronephrosis of the right kidney (fig. 2) and grade 2 hydronephrosis of the left kidney. A voiding cystogram was normal without any urinary extxavasation. Approximately 6 hours aRer birth the newborn had respiratory distress and paracentesis yielded 415 cc fluid. Laboratory evaluation of this fluid was consistent with urine, creatinine was 8.5 (normal 0.1 to 0.6) and blood urea nitrogen was 36 (normal 2 to 19). On the second day of life ultrasound again confirmed the ascites and massive right hydronephrosis with collecting system echogenicity consistent with possible hemorrhage. A mercaptoacetyltriglycine 3 renal scan revealed 20% function of the right kidney. Serum electrolytes were stable except for a creatinine of 3.0. Cystoscopy and left retrograde pyelogram were unremarkable, and attempts at a right retrograde pyelogram were unsuccessful. Through a flank incision the right kidney were explored and a 4 cm. lateral parenchymal rupture was repaired. The renal pelvis was extremely large, and the ureter was of normal caliber. Right cutaneous pyelostomy was
CURRENT CONCEPTS IN THE BIOLOGY AND MANAGEMENT OF WILMS TUMOR

AbstractPurpose: There have been a number of advances that have increased our understanding of the biology of Wilms tumor during the last decade. This information is now being incorporated into current pediatric oncology protocols. We present a summary of these advances and outline the current treatment of Wilms tumor.Materials and Methods: The medical literature was reviewed with an emphasis on the molecular biology of Wilms tumor.Results: The development of Wilms tumor involves several genes, including WT1, the Wilms tumor suppressor gene at 11p13. In addition, certain chromosomal regions (16q and 1p) might be used as prognostic factors for determining the intensity of therapy.Conclusions: Future protocols conducted by pediatric oncology groups will incorporate biological studies. The goal is to identify patients at low risk for relapse which will allow a reduction in treatment intensity and subsequent toxicity. Children at an increased risk for relapse can be selected for more intensive treatment.
Systematic relativistic Hartree-Fock calculation of deformed nuclei in s-d shell

A systematic study of even-even deformed nuclei in [ital s]-[ital d] shell is performed in the QHD framework by using relativistic Hartree-Fock calculations. The exchange of [sigma], [omega], [rho], and [pi] mesons and photons are included, the parameters of the model (meson masses and coupling constants) adopted are from an earlier least-squares fit to finite nuclear ground-state properties. We compare to the results of a similar calculation using parameters adjusted to fit the nuclear matter saturation data. We found great improvement in the total binding energy, however the deformation pattern is essentially not changed; for closed subshell nuclei we still find that the ground state favors a spherical solution. A well-defined constant Fermi surface in the [ital s]-[ital d] shell is obtained which is consistent with the experiment observation. The results are also compared to the corresponding relativistic Hartree calculations.
Design and Analysis of a Hyperspectral Microwave Receiver Subsystem

Recent technology advances have profoundly changed the landscape of modern radiometry by enabling miniaturized, low-power, and low-noise radio-frequency receivers operating at frequencies near 200 GHz and beyond. These advances enable the practical use of receiver arrays to multiplex multiple broad frequency bands into many spectral channels. We use the term “hyperspectral microwave” to refer generically to microwave sounding systems with approximately 50 spectral channels or more. In this paper, we report on the design and analysis of the receiver subsystem (lensed antenna, RF front-end electronics, and IF processor module) for the Hyperspectral Microwave Atmospheric Sounder (HyMAS) comprising multiple receivers near the oxygen absorption line at 118.75 GHz and the water vapor absorption line at 183.31 GHz. The hyperspectral microwave receiver system will be integrated into a new scanhead compatible with the NASA GSFC Conical Scanning Microwave Imaging Radiometer/Compact Submillimeter-wave Imaging Radiometer (CoSMIR/CoSSIR) airborne instrument system to facilitate demonstration and performance characterization under funding from the NASA ESTO Advanced Component Technology program. Four identical radiometers will be used to cover 108–119 GHz, and two identical receivers will be used to cover 173–183 GHz. Subharmonic mixers will be driven by frequency-multiplied dielectric resonant oscillators, and single-sideband operation will be achieved by waveguide filtering of the lower sideband. A relatively high IF frequency is chosen to facilitate miniaturization of the IF processor module, which will be fabricated using Low Temperature Co-fired Ceramic (LTCC) technology. Corrugated feed antennas with lenses are used to achieve a FWHM beamwidth of approximately 3.5 degrees. Two polarizations are measured by each feed to increase overall channel count, and multiple options will be considered during the design phase for the polarization diplexing approach. Broadband operation over a relatively high intermediate frequency range (18–29 GHz) is a technical challenge of the front-end receiver systems, and a receiver temperature of approximately 2000–3000K is expected over the receiver bandwidth. This performance, together with approximately 100-msec integration times typical of airborne operation, yields channel NEDTs of approximately 0.35K, which is adequate to demonstrate the hyperspectral microwave concept by comparing profile retrievals with high-fidelity ground truth available either by coincident overpasses of hyperspectral infrared sounders and/or in situ radiosonde/dropsonde measurements.
Contrast ultrasound assessment of angiogenesis by perfusion and molecular imaging.

There is great interest in the development of noninvasive methods for imaging angiogenic responses. Strategies for assessing angiogenesis have primarily relied on measuring perfusion-related characteristics, such as total blood flow or microvascular volume, or detecting abnormal vascular permeability. Techniques are now being developed that are capable of imaging the cellular and molecular alterations associated with neovessel growth and development. Contrast-enhanced ultrasound is a noninvasive imaging method that has great promise in terms of its ability to characterize changes in either microvascular perfusion or vascular endothelial phenotype. Techniques for evaluating perfusion by contrast ultrasound rely on the measurement of both microvascular blood volume and velocity. Accordingly, this technique can provide unique information on abnormalities in microvascular density and perfusion associated with adaptive and pathologic angiogenesis. Contrast ultrasound methods for imaging vascular phenotype duri...
Improving redirection with dynamic reorientations and gains

In head-mounted display systems, the confined size of the tracked space limits users from navigating larger virtual environments than the tracked physical space. Previous work suggests this constraint could be broken by asking users to back up or turn 180°whenever they encouter a wall in the real world [Williams et al. 2007]. In this work, we propose that the reorientation rate can be dynamically determined based on the user's instantaneous positional information and the shape of the navigable virtual space around the user. We conducted an experiment to compare our proposed dynamic reorientations with the previous Freeze-Turn reorientation. The results show that, with dynamic reorientations, participants walked a significantly longer distance between orientations than with Freeze-Turn reorientations.
Effect of Certain Metallic Salts on the Aging of a Tread Compound

Abstract The effect on aging produced by the addition of low concentrations of iron, copper, manganese, and mercury salts of higher aliphatic organic acids to a tread compound was investigated. The data obtained from aging in the bomb show that the presence of copper and manganese salts of organic acids in very small concentrations is harmful to the aging of rubber. As little as 0.1 per cent of either cupric stearate or manganic oleate is detrimental. Iron stearate has a less deleterious effect, but 0.5 per cent iron stearate produced much poorer aging than the blank. The mercury salts in the concentrations used—0.1 to 1.0 per cent—did not affect the aging so noticeably as the other salts. The effects of aging in the Bierer-Davis bomb and in the Geer oven are markedly different, both as to tensile strength and the hardening of the test strips. The bomb test at 70° C. was much more severe than the oven test at the same temperature. Further investigation will be made to determine which type of artificial ag...
Kindergarten children's emerging concepts of writing functions in the community

Abstract This study explored young children's concepts of the functions of writing in community contexts. Twenty kindergarten children responded to three videotaped vignettes depicting people writing in community settings. The children answered questions regarding who writes, what they write, where they write, and their purposes for writing. Results indicated that kindergarten children can identify a range of writing functions, including memory device, communication with others, learning, and personal expression. They also value writing and describe the negative consequences if people do not write. Results are discussed in terms of the theory and research on emergent literacy. Areas for further study are generated.
Persistent blockade of potassium-evoked serotonin release from rat frontocortical terminals after fluoxetine administration

We examined 5-HT and 5-HIAA release from frontal cortex evoked by high potassium chloride concentrations in rats pretreated for 3 days with high doses of the 5-HT uptake blocker fluoxetine or of dexfenfluramine, which both releases 5-HT and blocks its reuptake. The standard fluoxetine dose (30 mg/kg i.p.) was about 4 times the drug's ED50 in producing a serotonin-related behavioral effect, anorexia, while the dexfenfluramine dose (7.5 mg/kg i.p.) was about 6 times its ED50. These high doses were chosen in order to elucidate the mechanism by which similar doses of fluoxetine and dexfenfluramine had been found to produce long-term changes in serotonin dynamics. Fluoxetine decreased the basal release of both compounds; dexfenfluramine decreased basal 5-HIAA efflux without affecting the release of 5-HT release. Potassium-evoked 5-HT release was unchanged after dexfenfluramine pretreatment but was suppressed by fluoxetine doses as low as 7.5 mg per kg per day. Basal release of 5-HT and 5-HIAA returned to normal after 7 days of fluoxetine pretreatment, but evoked release continued to be suppressed. These data suggest that long-term changes in brain serotonin dynamics after high doses of dexfenfluramine or fluoxetine are related to the drug's mechanisms of action, specifically their blockade of 5-HT reuptake.
The impact of US economic variables on Bank of Canada policy: direct and indirect responses

Abstract The impact of US economic variables on Canadian monetary policy is assessed using quarterly data for 1963-88. Canadian monetary base growth is regressed upon the least-squares predictors of 11 US and Canadian variables using a generalized least squares procedure that permits isolation of (i) direct responses by the monetary authority to its expectations of the US variables, and (ii) indirect responses to past US influences that impact upon the current fitted values of the Canadian variables. The results reveal significance of both direct and indirect US influences on Canadian policy across fixed and floating exchange rate regimes.
Biochemical reconstitution of steroid receptor•Hsp90 protein complexes and reactivation of ligand binding.

Hsp90 is an essential and highly abundant molecular chaperone protein that has been found to regulate more than 150 eukaryotic signaling proteins, including transcription factors (e.g. nuclear receptors, p53) and protein kinases (e.g. Src, Raf, Akt kinase) involved in cell cycling, tumorigenesis, apoptosis, and multiple eukaryotic signaling pathways 1,2. Of these many 'client' proteins for hsp90, the assembly of steroid receptor•hsp90 complexes is the best defined (Figure 1). We present here an adaptable glucocorticoid receptor (GR) immunoprecipitation assay and in vitro GR•hsp90 reconstitution method that may be readily used to probe eukaryotic hsp90 functional activity, hsp90-mediated steroid receptor ligand binding, and molecular chaperone cofactor requirements. For example, this assay can be used to test hsp90 cofactor requirements and the effects of adding exogenous compounds to the reconstitution process. The GR has been a particularly useful system for studying hsp90 because the receptor must be bound to hsp90 to have an open ligand binding cleft that is accessible to steroid 3. Endogenous, unliganded GR is present in the cytoplasm of mammalian cells noncovalently bound to hsp90. As found in the endogenous GR•hsp90 heterocomplex, the GR ligand binding cleft is open and capable of binding steroid. If hsp90 dissociates from the GR or if its function is inhibited, the receptor is unable to bind steroid and requires reconstitution of the GR•hsp90 heterocomplex before steroid binding activity is restored 4 . GR can be immunoprecipitated from cell cytosol using a monoclonal antibody, and proteins such as hsp90 complexed to the GR can be assayed by western blot. Steroid binding activity of the immunoprecipitated GR can be determined by incubating the immunopellet with [3H]steroid. Previous experiments have shown hsp90-mediated opening of the GR ligand binding cleft requires hsp70, a second molecular chaperone also essential for eukaryotic cell viability. Biochemical activity of hsp90 and hsp70 are catalyzed by co-chaperone proteins Hop, hsp40, and p23 5. A multiprotein chaperone machinery containing hsp90, hsp70, Hop, and hsp40 are endogenously present in eukaryotic cell cytoplasm, and reticulocyte lysate provides a chaperone-rich protein source 6. In the method presented, GR is immunoadsorbed from cell cytosol and stripped of the endogenous hsp90/hsp70 chaperone machinery using mild salt conditions. The salt-stripped GR is then incubated with reticulocyte lysate, ATP, and K+, which results in the reconstitution of the GR•hsp90 heterocomplex and reactivation of steroid binding activity 7. This method can be utilized to test the effects of various chaperone cofactors, novel proteins, and experimental hsp90 or GR inhibitors in order to determine their functional significance on hsp90-mediated steroid binding 8-11.
Vehicle Moonroof Design for Wind Noise

A study was undertaken to address excessive moonroof wind noise in some vehicles. Mathematical models were developed to understand noise generation mechanisms associated with the moonroof system, and these models were used to investigate ways to reduce vehicle interior noise levels. Extensive acoustic & vibration testing was performed on vehicles in the wind tunnel and on the test track. The wind tunnel and test track data were analyzed in a sound quality laboratory for root cause analysis. CFD (computational fluid dynamics) simulations were performed to understand flow behavior over the moonroof in both modes of operations (vented and fully retracted). An experimental moonroof deflector optimization study was developed and conducted to identify the necessary design changes to minimize the vehicle interior noise level for fully retracted condition. Variability studies were also performed on the moonroof flushness, deflector height, and retraction distance. Through extensive analyses, using both experimental and analytical techniques, the main causes of wind noise associated with moonroof system were identified. Vehicle moonroof design recommendations were generated for significant wind noise reductions.Copyright © 2004 by ASME
Benchmarking instructional costs and productivity: The Kansas study

This chapter discusses the development and implementation of the Kansas Study of Instructional Costs and Productivity, which collects and reports data on community college instructional costs and faculty workloads. The project provides data for both intra- and inter-institutional comparisons about how much community college faculty teach and the cost of that instruction at the discipline level.
Nonparametric estimation of quadratic regression functionals

Quadratic regression functionals are important for bandwidth selection of nonparametric regression techniques and for nonparametric goodness-of-fit test. Based on local polynomial regression, we propose estimators for weighted integrals of squared derivatives of regression functions. The rates of convergence in mean square error are calculated under various degrees of smoothness and appropriate values of the smoothing parameter. Asymptotic distributions of the proposed quadratic estimators are considered with the Gaussian noise assumption. It is shown that when the estimators are pseudo-quadratic (linear components dominate quadratic components), asymptotic normality with rate n-1/2 can be achieved.
Theoretical study of low-energy electron and positron scattering on Be, Mg and Ca

Static exchange and static exchange plus polarisation calculations are carried out for elastic electron and positron scattering with Be, Mg and Ca. All three atoms are found to have a low-lying 2P resonance in the electron scattering case. Magnesium and calcium are also predicted to have higher lying 2D shape resonances near 2.0 and 0.7 eV, respectively. The 2D resonance in Mg is very weak and broad ( Gamma >3.0 eV) while that in Ca is much more pronounced and is much narrower ( Gamma approximately 0.6 eV). These findings are in agreement with recent experiments. In addition a very broad feature appears in e--Be d-wave scattering near 5 eV. While maxima occur in the p-wave cross sections for positron scattering, these do not appear to be due to resonances. However, evidence is provided for exceptionally broad resonances in d-wave positron scattering and for a virtual (or antibound) state in s-wave scattering.
An Anonymous Argument Against Mixture

Aristotle's de Generatione et Corruptione I io (327 b 35-328 a 7) contains an interesting argument against the possibility of mixture. According to "some people", he writes, "it is impossible for one thing to be mixed with another; for (a) if the ingredients still exist and are not altered at all, they are no more mixed than they were before, but are in a similar state; and (b) if one ingredient is destroyed they have not been mixed, but one ingredient exists while the other does not, whereas mixture is composed of ingredients which remain what they were before; and in the same way, (c) even if, both the ingredients having come together, each of them has been destroyed, there is no mixture ; for things which have no existence at all cannot have been mixed" (trans. Forster). Attempts to identify the "some people" of this passage have not been very fruitful. Joachim, in his extensive commentary, does not even take up the problem *). Verdenius and Waszink were at first reminded of Diogenes of Apollonia DK 64 B2, but the revised edition of their Comments drops the suggestion, rightly, I think 2). Cherniss sees the argument as "derived from Zeno but ... not used for this purpose by Zeno himself", and as "very probably Megarian" 3). Solmsen also mentions Zeno and thinks that the argument "may have figured in Zeno's polemic against Empedocles* use of mixture", and "may have had the same form" as DK
Maintaining US leadership in human spaceflight

Abstract What is the right way for the USA to maintain leadership in human spaceflight—important for strategic as much as commercial and scientific reasons—now that China has joined the club? After analysing China's decision to pursue human spaceflight and its implications for the USA, the author argues that isolating China will be counterproductive to US interests, not least by keeping its intentions unknown. Nor should the USA engage in a ‘race’ with that country. Given China's desire for cooperation and the willingness of most other nations to collaborate with it, trying to prevent technology transfer to it will also be unrealistic. The USA should engage China cooperatively in order to shape its programme and to manage transfers.
Vitamin B12 and older adults.

Purpose of reviewTo review the prevalence, causes and functional significance of vitamin B12 deficiency in vulnerable subpopulations including older adults and the developing embryo.Recent findingsIt is becoming increasingly recognized that the susceptibility to vitamin B12 deficiency may change thr
Fusion Reactor Aspects of the Compact Torus

This paper summarizes several studies of fusion reactors based on the compact torus (CT). A wide variety of reactor configurations can be projected within present understanding of the possible types of CT and their macroscopic stability and confinement properties. Three types of CT are considered here, the field-reversed-configuration having BToroidal = 0, the Spheromak with BT ≠ 0, and CT’s formed with particle rings. For each type, either fixed or moving-ring possibilities are offered along with pulsed or steady operation. In all cases the CT configuration lends itself to simplified blanket and coil design. In certain, important cases a reactor-scale CT is predicted to produce small unit power (10–100 MWe) facilitating small-scale pilot plants and eventual modularity.
Optical hyperspace: negative refractive index and subwavelength imaging in anisotroptic dielectric metamaterials

We propose an approach to far field optical imaging below the diffraction limit, based on dielectric metamaterials with strong anisotropy. As opposed to the "superlens" that relies on negative index materials, our method allows image magnification and is robust with respect to material losses.
Application of 1D and 2D NMR techniques to the structure elucidation of the O-polysaccharide from Proteus mirabilis O: 57

The LPS O-polysaccharide (O-PS) produced by Proteus mirabilis serotype O: 57 (ATCC 49995) was shown by NMR spectroscopy and chemical analysis to be a high-molecular-weight acidic branched polymer of pentasaccharide repeating units, composed of d-glucose, d-galactose, 2-acetamido-2-deoxy-d-galactose and glycerophosphate residues (1:2:2:2:1). Application of one-and two-dimensional NMR methods allowed the complete assignment of notoriously crowded 1H and 13C spectra of the O-PS, leading to the determination of its structure. Several of the NMR techniques used were applied for the first time to the structure elucidation of polysaccharides. The resonances of galactose H5, H6 and H6′ were identified by a 1D analog of 3D NOESY-TOCSY and 2D {1H, 1H} triple-quantum experiments. The position and the nature of the phosphate group were determined from 2D 31P (ω1)-half-filtered COSY and 2D 31P-relayed COSY spectra. 2D HMQC-TOCSY and 2D single-quantum proton-carbon long-range correlation techniques were used to overcome the difficulties of severe overlap and higher order effects in the 1H NMR spectrum of the O-PS. The latter technique, together with 2D NOESY, enabled us to identify the substitution positions, the anomeric configurations and the sequence of the component glycose residues in the O-PS.
A prospective study of sex hormone-binding globulin and fatal cardiovascular disease in Rancho Bernardo men and women

Sex hormone-binding globulin (SHBG) has been shown to be associated with several cardiovascular disease (CVD) risk factors. We examined the prospective association between SHBG and the risk of CVD and ischemic heart disease (IHD) death in 760 men and 624 women, aged 50-82 yr, who were free of heart disease at baseline. Health status and cause of death were determined annually for 99.9% of the cohort for 19 yr. SHBG correlated negatively with body mass index in both sexes and increased with age in men. After adjusting for age and body mass index, SHBG correlated negatively with fasting plasma glucose in men and women and with total cholesterol and triglycerides in men. There were 235 CVD and 134 IHD deaths in men and 153 CVD and 80 IHD deaths in women over the 19-yr follow-up. The quintile of baseline SHBG was unrelated to CVD or IHD mortality rate. No association was found in sex-specific, multiply-adjusted Cox proportional hazard models. All risk ratios were close to 1, and 95% confidence intervals were narrow and included 1. Although associated with several strong heart disease risk factors, the SHBG level does not predict CVD or IHD mortality in men or women.
Cancellation of coupled and decoupled NMR signals of protonated carbons

Abstract A simple two-step pulse sequence ( π/2( 13 C )-τ-π/2( 1 H ), π( 13 C )-τ- acquire 13 C ) is used for selective cancellation of coupled and decoupled 13C signals of all protonated carbons. Adjustment of the evolution period τ ≈ 1 (2J) is not critical, therefore the sequence appears to be very suitable for generating subspectra of nonprotonated carbons.
Re-conceiving quantum theories in terms of information-theoretic constraints

Abstract This paper examines Bub's interpretation of the foundational significance of the theorem of Clifton, Bub, and Halvorson (CBH) which characterizes quantum theories in terms of information-theoretic constraints. Bub argues that quantum theory must be re-conceived of as a principle theory of information where information is a new physical primitive, to the exclusion of hidden variable theories. I will argue, contrary to Bub, that the CBH theorem cannot be used to exclude hidden variables theories. Drawing inspiration from Bub, I sketch an alternative conception of quantum mechanics as a theory of information, but one which embraces all empirically equivalent quantum theories.
The use of chemometric techniques in process analytical method development and operation

Abstract Process analytical chemistry is one area in which chemometrics can have a considerable practical impact. In many cases, a good multivariate calibration method is necessary, but not sufficient, for successful development and implementation of a process analytical method. This statement is particularly true in the case of spectral process analyzers, which can produce large volumes of very complex and non-selective data. The implementation of a process spectroscopy method can be thought of as a series of discrete procedures, each of which can be greatly aided through the use of chemometric methodologies: (i) gross outlier removal; (ii) data filtering/pre-linearization; (iii) sample selection; (iv) variable selection; (v) calibration; (vi) on-line method fault detection; and (vii) calibration updating/maintenance. The purpose of this paper is to both present recent chemometric approaches to each of these steps, and, in light of the experimental results reported, to discuss possibilities for new or improved methodologies. Recent approaches to most of these steps will be presented using data obtained from a process spectrometer installed on a polymer production unit.
Bifurcation Structure of a Class of SN-invariant Constrained Optimization Problems

In this paper we investigate the bifurcations of solutions to a class of constrained optimization problems. This study was motivated by annealing problems which have been used to successfully cluster data in many different applications. Solving these problems numerically is challenging due to the size of the space being optimized over, which depends on the size and the complexity of the data being analyzed. The type of constraints and the form of the cost functions make them invariant to the action of the symmetric group on N symbols, S N , and we capitalize on this symmetry to describe the bifurcation structure. We ascertain the existence of bifurcating branches, address their stability, and compare the stability to optimality in the constrained problem. These theoretical results are used to explain numerical results obtained from an annealing problem used to cluster data.
Simultaneous oxygen production and nitrogenase activity of an ammonia-excreting mutant of the cyanobacterium Anabaena variabilis in a co-culture with wheat

A mutant strain of Anabaena variabilis, strain SA-1 that supported growth of wheat plants in a hydroponic co-culture in nitrogen (N) free medium also produced enough oxygen (O2) to support root respiration. The steady-state concentration of net O2 in the co-culture was dependent on incident light intensity. At an incident photosynthetic photoflux (PPF) of 1000 μmol photons·m−2·s−1, net O2 evolution by the co-culture in the root zone reached a maximum value of about 220 μmol O2 evolved·h−1·mg chlorophyll (Chl)−1. The O2 concentration in the rhizosphere of the co-culture stayed above the ambient air level. O2 uptake in the dark by strain SA-1-supplemented wheat roots washed free of cyanobacterium was higher than the root respiration of nitrate-grown plants. Nitrate-grown plants required aeration for maximum growth while the wheat-cyanobacterial co-culture can be cultured without aeration. These results show that O2 produced by strain SA-1 can be used to supply the O2 needs for root respiration of wheat. Respiration reduced net O2 evolution by the mutant SA-1, decreasing the partial pressure of O2 at the sites of cyanobacterial attachment to the roots. This led to an increase in the specific activity of nitrogenase of the co-culture at the high light intensities used to support wheat growth. This activity of about 30 μmol ethylene produced·mg Chl−1·h−1 was three-fold higher than the activities obtained with the free-living strain SA-1 assayed at the same light intensity. In the co-culture, ammonia produced by the mutant strain SA-1 was not detectable. The NHinf4sup+produced by strain SA-1 was used by the wheat plants and, under these conditions, the total N content of the plants reached as high as 85% of the total N content of nitrate-grown plants. In the co-culture system the metabolism of wheat and the cyanobacterium complemented each other, leading to higher plant growth in N-free medium.
Synthesis and biological activity of LH-RH antagonists modified in position 1.

Abstract As part of our studies on the design of more potent antagonists of the LH-RH (luteinizing hormone-releasing hormone) decapeptide, twelve new highly soluble D-Arg 6 -analogs have been synthesized. These peptides contain modifications in position 1 and are typified by the general formula (N-acetyl-X 1 , D-p-Cl-Phe 2 , D-Trp 3 , D-Arg 6 , D-Ala 10 ) LH-RH. We have found that a lypophilic, aromatic substituent is required in position 1 in order to elicit antiovulatory activity at a dose as low as 3 μg. The larger the hydrophobic amino acid (X: p-Br-Phe, β-Nal-2) in position 1, the higher is the antiovulatory activity that can be attained. Analogs with non-aromatic or hydrophilic amino acids (X: Gly, Leu, Arg, His, Glu) in position 1 generally have much lower activities in this series of LH-RH antagonists.
Validation of the Telephone Interview for Cognitive Status-modified in Subjects with Normal Cognition, Mild Cognitive Impairment, or Dementia

Background: The telephone assessment of cognitive functions may reduce the cost and burden of epidemiological studies. Methods: We validated the Telephone Intervi
Stability of polyaniline in air and acidic water

Polyaniline is a member of the class of electrically conducting polymers, having possible commercial applications such as coatings. Aqueous-based polyaniline coatings are preferred over organic solvent or concentrated strong acid based coatings because water is not a pollutant. The overall goal of this study was to further the development of water-based polyaniline coatings by an examination of the effect of acidic water (pH 1.18) and air on polyaniline. Knowledge of the effect of water on the structure, molecular weight, electrical conductivity, and diffusion of the dopant assisted in ascertaining whether polyaniline degraded with water exposure. Knowledge of how Fourier transform infrared (FTIR) spectra would be affected by dry air was important for determining if polyaniline was chemically stable with time. The results showed that the molecular weight, ultraviolet–visible and FTIR spectra, and carbon-to-nitrogen molar ratio in the polymer backbone all remained unchanged during acidic water immersion. The constant nature of these physical parameters showed a high degree of water stability. A chloride ion diffusion coefficient of 2.8 to 85 × 10−9 cm2/h, the chloride concentration, and the electrical conductivity were also measured with the water immersion time. Aging polyaniline powders in a desiccator for 5 years showed no effect on the molecular structure, as indicated by the FTIR spectrum. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 807–822, 2003
Vortex lattice structure in uniaxial superconductors.

The structure of the vortex lattice in anisotropic, unaxial superconductors in the domain ${H}_{c1}\ensuremath{\ll}H\ensuremath{\ll}{H}_{c2}$ is considered within the London approach. To first order in the small parameter ${\frac{(L}{\ensuremath{\lambda})}}^{2}$, where $L$ is the average intervortex spacing and $\ensuremath{\lambda}$ is the average penetration depth, there exists a continuum of different lattices with the same free energy for any direction of the magnetic induction $\mathbf{B}$ with respect to the crystal. It is shown that the degeneracy is removed if terms in the free energy of order ${\frac{(L}{\ensuremath{\lambda})}}^{4}$ are taken into account, yielding both a unique structure and a preferred orientation of the vortex lattice with respect to the direction of $\mathbf{B}$ within the crystal. Parameters of the primitive cell for this structure are obtained and evaluated for known values of the anisotropy of Y${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$. For the particular case of vortices parallel to the Cu-O planes the degeneracy remains exact (within the London approach), which should make this lattice more susceptible to disorder. The magnetization is shown to be almost parallel to the $\stackrel{^}{c}$ crystal direction for all orientations of the external field ${\mathbf{H}}_{0}$, except in a narrow domain where ${\mathbf{H}}_{0}$ is nearly normal to $\stackrel{^}{\mathbf{c}}$.
Information capacity of a seeing-limited imaging system

Abstract Regarding an imaging system as a communication channel allows one to characterize it in terms of Shannon's statistical information ideas. We consider here in quantitative terms how atmospheric turbulence degrades the processing of information in astronomical objects that are being imaged by a ground-based telescope. We calculate the maximum information that can be transmitted, in the presence of additive detector noise, by such a telescope, i.e., its information capacity, subject to certain physically relevant constraints of fixed integrated emissive flux and fixed integrated spatial power spectrum.