cssi/SciSciGPT-SciSciNet huggingface dataset:
Study of wavelength shift in quantum well structure by MOCVD selective area growth

Bulk InGaAs and InGaAsP and quantum well structure were grown on different oxide pattern. The material composition varies with the width of oxide pattern. The PL peak wavelength of the grown SAG quantum well is determined by the variation of both the material composition and the well width. We have experimentally identified the ratio of the contribution from the two sources, which agree well with the theoretical calculation from the measured thickness changes.
Long-term follow-up of patients with rectal cancer managed by local excision with and without adjuvant irradiation.

Objective The long-term outcomes of patients undergoing local excision with or without pelvic irradiation were examined to define the role of adjuvant irradiation after local excision of T1 and T2 rectal cancers. Methods Ninety-nine patients with T1 or T2 rectal cancers underwent local excision with or without adjuvant irradiation at Massachusetts General Hospital and Emory University Hospital between January 1966 and January 1997. Of these, 52 patients were treated by local excision alone and 47 patients by local excision plus adjuvant irradiation. Twenty-six of these 47 patients were treated by irradiation in combination with 5-fluorouracil chemotherapy. The outcomes of these groups were compared. Results The 5-year actuarial local control and recurrence-free survival rates were 72% and 66%, respectively, for the local excision alone group and 90% and 74%, respectively, for the adjuvant irradiation group. This improvement in outcome was evident despite the presence of a higher-risk patient population in the adjuvant irradiation group. Adverse pathologic features such as poorly differentiated histology and lymphatic or blood vessel invasion decreased local control and recurrence-free survival rates in the local excision only group. Adjuvant irradiation significantly improved 5-year outcomes in patients with high-risk pathologic features. Four cases of late local recurrence were seen at 64, 72, 86, and 91 months in the adjuvant irradiation group. Conclusions The authors recommend adjuvant chemoradiation for all patients undergoing local excision for T2 tumors, and for T1 tumors with high-risk pathologic features. The four cases of late local failures beyond 5 years in the adjuvant irradiation group underscores the need for careful long-term follow-up in these patients.
Human aldehyde dehydrogenase: kinetic identification of the isozyme for which biogenic aldehydes and acetaldehyde compete

Michaelis constants and maximal velocities for phenylacetaldehyde (a metabolite of phenylethylamine), 3,4-dihydroxyphenylacetaldehyde (a metabolite of dopamine), 5-hydroxyindole acetaldehyde (a metabolite of serotonin), and 3,4-dihydroxyphenylglycolaldehyde (a metabolite of epinephrine and norepinephrine) have been determined for both cytoplasmic (E1) and mitochondrial (E2) isozymes of human liver aldehyde dehydrogenase (EC 1.2.1.3). Kinetic constants with biogenic aldehydes have never been previously determined for individual homogeneous isozymes of aldehyde dehydrogenase from any species. Mathematical treatment of these constants suggests that competition with acetaldehyde during alcohol metabolism would severely inhibit dehydrogenation of biogenic aldehydes with the mitochondrial and not the cytoplasmic isozyme of human liver aldehyde dehydrogenase.
Using the Critical Outcome Technique to Demonstrate Financial and Organizational Performance Results

The problem and the solution. It has been shown that managers prefer results-type evaluation when making decisions about how to invest in human resource development (HRD) activities. Unfortunately, in the absence of using rigorous, front-end performance analysis to identify outcomes for evaluation, most practitioners are faced with a complex array of tools and techniques to perform post-hoc analyses of their HRD efforts. This article demonstrates how Critical Outcome Technique can be used as a simple and effective way to demonstrate the effectiveness of HRD programs. Of importance in program evaluation are the constructs of the evaluation process, organizational culture, evaluation context, and decision-maker perceptions of the perceived ease of use and perceived usefulness of evaluation reports.
Bovine monocyte TLR2 receptors differentially regulate the intracellular fate of Mycobacterium avium subsp. paratuberculosis and Mycobacterium avium subsp. avium

Pathogenic mycobacterial organisms have the capacity to inhibit macrophage activation and phagosome maturation. Although the mechanism is complex, several studies have incriminated signaling through TLR2 receptors with subsequent activation of the MAPK pathway p38 (MAPKp38) and overproduction of IL-10 in the survival of pathogenic mycobacterial organisms. In the present study, we compared the response of bovine monocytes with infection by Mycobacterium avium subspecies paratuberculosis (MAP), the cause of paratuberculosis in ruminants, with the closely related organism M. avium subspecies avium (Maa), which usually does not cause disease in ruminants. Both MAP and Maa induced phosphorylation of MAPKp38 by bovine monocytes; however, addition of a blocking anti-TLR2 antibody partially prevented MAPKp38 phosphorylation of MAP-infected monocytes but not Maa-infected monocytes. Addition of anti-TLR2 antibody enhanced phagosome acidification and phagosome-lysosome fusion in MAP-containing phagosomes and enabled monocytes to kill MAP organisms. These changes were not observed in Maa-infected monocytes. The effect on phagosome maturation appears to occur independently from the previously described inhibitory effects of IL-10 on phagosome acidification and organism killing, as IL-10 production was not affected by addition of anti-TLR2 antibody to monocyte cultures. Therefore, signaling through the TLR2 receptor appears to play a role in phagosome trafficking and antimicrobial responses in MAP-infected bovine mononuclear phagocytes.
A reinforcement exchange analysis of the power aspects of program evaluation.

Power, examined within a reinforcement exchange model, is proposed as an essential dynamism through which program evaluation is mounted, executed, and utilized. The ability of the program evaluator to influence or control the policies or operations of the evaluatee depends chiefly on an exchange of behaviors which nets all participants of the evaluation interaction a fair and sufficient “payoff” in terms of contingent reinforcements. Other contextual features of program evaluation, particularly those that constrain on utilization of the recommendations, are briefly discussed.
Calibration and accuracy of optical slope measurements for short wind waves

A thorough understanding of the hydrodynamics of short ocean wave is important for interpreting measurements made by active microwave remote sensing instruments. However, conventional methods for studying the structure of a water surface are not capable of resolving the fine scale structure of the surface, especially in the ultra-gravity and capillary wavelengths. Optical instruments have the potential for resolving the fine-scale structure of the ocean surface, however, methods for calibrating these instruments and verifying the accuracy of the measurements have not been developed. In this paper we describe a multi-faceted approach for verifying the accuracy and calibration of an imaging wave slope gauge (ISG). The first step is a thorough theoretical analysis of the geometrical optics and photometry. A detailed discussion on the relationship between surface slope and observed pixel intensity is presented. This discussion includes second order effects which may tend to bias the results. Secondly, calibration objects formed from thin transparent Perspex sheets with known slope and height profiles are retrieved. The results show that the measurements of the water surface shape are accurate enough to compute 2-D wave number spectra.
Relevance of Transgenic Mouse Models to Human Alzheimer Disease

During the past 2 decades, the elucidation of susceptibility and causative genes for Alzheimer disease as well as proteins involved in the pathogenic process has greatly facilitated the development of genetically altered mouse models. These models have played a major role in defining critical disease-related mechanisms and in evaluating novel therapeutic approaches, with many treatments currently in clinical trial owing their origins to studies initially performed in mice. This review discusses the utility of transgenic mice as a research tool and their contributions to our understanding of Alzheimer disease.
Physical aging of maltose glasses

Physical aging is the alteration in the physical properties of a glass, as a function of time, at temperatures below its glass transition temperature (Tg). The physical aging of maltose glasses, prepared from maltose monohydrate sugar, was studied using differential scanning calorimetry (DSC). The maltose was aged at 30 degrees C for times ranging from 5 min to approximately 10 days. The Tg and change in heat capacity of the unaged and aged maltose glasses were measured. The change in enthalpy relaxation with aging time was determined by integrating the difference between the aged and the unaged DSC thermograms. The enthalpic relaxation data were adequately described by the Williams-Watts equation.
Imide oligomers containing pendent and terminal phenylethynyl groups

Abstract As part of a programme to develop high performance/high temperature structural resins for aeronautical applications, imide oligomers containing pendent and terminal phenylethynyl groups were prepared, characterized and the cured resins evaluated as adhesives and composite matrix resins. As a means of controlling the molecular weight between reactive sites (i.e. crosslink density), varying amounts of phenyl-ethynyl groups were distributed randomly along the imide oligomer whose calculated number-average molecular weight was 5000 g mol−1. Upon thermal cure at 350–371°C for 1 h in air, the phenylethynyl group undergoes a complex reaction resulting in chain extension, branching and crosslinking. The products depend upon several factors such as the relative concentration of phenylethynyl groups, molecular mobility of the growing polymer and conformational restrictions and have been postulated to be predominantly highly conjugated polyenes. In general, the cured resins have a favourable combination of properties including good thermal stability, solvent and moisture resistance and good toughness. The amide acid oligomer solutions were processed into thin films, adhesive tape and carbon fibre prepreg. Neat resin plaques were fabricated from imide oligomer powder by compression moulding. The maximum processing pressure was 1.4 MPa and the cure temperature varied from 350–371°C for 1 h for the composites, adhesive panels and neat resin mouldings. The properties of the cured imide oligomers containing pendent and terminal phenylethynyl groups are compared with those of cured oligomers of similar composition and molecular weight which contain either terminal or pendent phenylethynyl groups. Published by Elsevier Science Ltd.
Isolation and characterization of rat and human glyceraldehyde-3-phosphate dehydrogenase cDNAs: genomic complexity and molecular evolution of the gene

Full length cDNAs encoding the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from rat and man have been isolated and sequenced. Many GAPDH gene-related sequences have been found in both genomes based on genomic blot hybridization analysis. Only one functional gene product is known. Results from genomic library screenings suggest that there are 300-400 copies of these sequences in the rat genome and approximately 100 in the human genome. Some of these related sequences have been shown to be processed pseudogenes. We have isolated several rat cDNA clones corresponding to these pseudogenes indicating that some pseudogenes are transcribed. Rat and human cDNAs are 89% homologous in the coding region, and 76% homologous in the first 100 base pairs of the 3'-noncoding region. Comparison of these two cDNA sequences with those of the chicken, Drosophila and yeast genes allows the analysis of the evolution of the GAPDH genes in detail.
System-level modeling of microprocessor reliability degradation due to BTI and HCI

Negative bias temperature instability (NBTI), positive bias temperature instability (PBTI) and hot carrier injection (HCI) are leading reliability concerns for modern microprocessors. In this paper, a framework is proposed to analyze the impact of NBTI, PBTI and HCI on state-of-art microprocessors and to accurately estimate microprocessor lifetimes due to each wearout mechanism. Our methodology finds the detailed electrical stress and temperature of each device within a microprocessor system running a variety of standard benchmarks. Combining the electrical stress profiles, thermal profiles, and device-level models, we do timing analysis on the critical paths of a microprocessor using our methodology to characterize microprocessor performance degradation due to BTI and HCI. In addition, we study DC noise margins in conventional 6T SRAM cells as a function of BTI and HCI degradation to provide insights on reliability of memories embedded within microprocessors under realistic use conditions.
A facile procedure for purifying maize chloroplast RNA polymerase from whole cell homogenates.

Two DNA-dependent RNA polymerases have been purified from homogenates of maize leaves by a relatively rapid procedure involving Sepharose 4B and DEAE-cellulose chromatography followed by resolution of two RNA polymerasies on phosphocellulose. The RNA polymerase eluting from phosphocellulose at 0.11 M (NH4)2SO4 is inhibited strongly by low levels of α-amanitin and possesses catalytic properties and polypeptide subunits like those of maize nuclear RNA polymerase II. The RNA polymerase eluting from phosphocellulose at 0.15 M (NH4)2SO4 resembles the RNA polymerase solubilized from isolated maize chloroplasts in many ways. This enzyme and that isolated from chloroplasts are resistant to α-amanitin and rifamycin-SV at high concentrations. Both RNA polymerases have virtually the same Mn2+ and Mg2+ optima, Mg2+Mn2+ activity ratios, (NH4)2SO4 sensitivity, kinetics of UMP incorporation, and temperature optima. Electrophoresis of this phosphocellulose-purified RNA polymerase on denaturing polyacrylamide slab gels reveals 14 heavily stainable polypeptides that are identical in number and molecular mass to those from chloroplast RNA polymerase. Moreover, two-dimensional tryptic maps of the 14 polypeptides from the phosphocellulose-purified RNA polymerase are very similar to the maps of corresponding polypeptides from chloroplast RNA polymerase. Using this method, relatively large quantities (0.5 mg/kg leaves) of a form of chloroplast RNA polymerase can be prepared in a few days.
Genetically Engineered: Why Some Venture Capital Firms Are More Successful Than Others

While venture capital has received a tremendous amount of attention, prior research has predominantly looked at venture capital firms (VCFs) post raising their first fund. In this paper, we move the point of analysis back further and ask what type of founding team experience best predicts VCF success, controlling for firm strategy, firm size, and the environment upon which the firm was born. Empirical results show that venture capital, senior management, and consulting experience aids VCF success, while entrepreneurial experience impedes it. None of the control variables affect a VCF's ability to raise subsequent funds.
Premature Emission After Spinal Cord Injury

ABSTRACTPhysicians and psychologists almost always treat premature emission or ejaculation as a psychological problem. We report on 6 men who had sudden onset of severe premature emission after spinal cord injury. All men suffered spinal cord injury related to trauma at the T12-L1 level, and had areflexic bladders after the injury. Two men had normal penile sensation. None of the men had premature ejaculation before injury with average time of intercourse of 10 to 20 minutes before orgasm. After the injury they noticed emission before or at vaginal entry. Two patients reported emission with any sexual thoughts and 1 had emission when startled in a nonsexual manner. Sexual therapy using squeeze and stop/start techniques was unsuccessful in all cases. Patients were started on phenoxybenzamine, terazosin or prazosin and reported slight improvement. We believe that injury in the conus area of the spinal cord may disinhibit the ejaculatory mechanism and allow for premature emission.
Congestive Heart Failure in Infancy Treated by Early Repair of Ventricular Septal Defect

Six patients, ages 6, 10, 11, 15, 22, and 33 months, in severe congestive heart failure unresponsive to intensive medical therapy underwent operative closure of large ventricular septal defects successfully. The intraoperative management and the postoperative care are presented in detail. Our early results are gratifying and justify early closure of life-threatening ventricular septal defects in infants.
Familial cholesteatoma in East Anglia, UK.

Objective To report a cluster of families affected by cholesteatoma in the East Anglia region of the UK. Setting Otology service for the population of Norfolk and North Suffolk, East Anglia, UK. Method Prospective and systematic collection of family history data for patients presenting with cholesteatoma over 10 years. Result Several families were identified with affected individuals over several generations. Conclusion There is likely to be a genetic propensity for cholesteatoma in some individuals.
MECHANICAL PROPERTIES OF FISH AND BEEF GELS PREPARED WITH AND WITHOUT WASHING AND SODIUM CHLORIDE

Excellent gels, as measured by fold test, were prepared from three species of fish without first washing the minced tissue. Dependent on species (red hake, cod, or winter flounder), excellent to adequate gels, as determined by the fold test, could be prepared from fish muscle without NaCl provided that the minced tissue was washed prior to gel formation. Postrigor beef formed inadequate gels while excellent to good gels could be produced from prerigor beef although salt was a requirement. The concentration of contractile proteins in fish gels was estimated and they did not appear to be a major factor determining gel quality. Soluble muscle protein did not appear to interfere with gel formation either. Percent expressible moisture, percent recovery, and modulus of deformability did not relate well to fold test scores.
Minimum-Fuel Low-Earth Orbit Aeroassisted Orbital Transfer of Small Spacecraft

The problem of small spacecraft minimum-fuel heat-rate-constrained aeroassisted orbital transfer between two lowEarth orbits with inclination change is considered. Assuming impulsive thrust, the trajectory design is described in detail and the aeroassisted orbital transfer is posed as a nonlinear optimal control problem. The optimal control problem is solved using an hp-adaptive pseudospectral method, and the key features of the optimal trajectories are identified. It was found that the minimum impulse solutions are obtained when the vehicle enters the atmosphere exactly twice. Furthermore, even for highly heat-rate-constrained cases, the final mass fraction of the vehicle was fairly large. Finally, the structural loads on the vehiclewere quite reasonable, even in the caseswhere the heating rate was unconstrained.
Paneth cells, antimicrobial peptides and maintenance of intestinal homeostasis

Building and maintaining a homeostatic relationship between a host and its colonizing microbiota entails ongoing complex interactions between the host and the microorganisms. The mucosal immune system, including epithelial cells, plays an essential part in negotiating this equilibrium. Paneth cells (specialized cells in the epithelium of the small intestine) are an important source of antimicrobial peptides in the intestine. These cells have become the focus of investigations that explore the mechanisms of host-microorganism homeostasis in the small intestine and its collapse in the processes of infection and chronic inflammation. In this Review, we provide an overview of the intestinal microbiota and describe the cell biology of Paneth cells, emphasizing the composition of their secretions and the roles of these cells in intestinal host defence and homeostasis. We also highlight the implications of Paneth cell dysfunction in susceptibility to chronic inflammatory bowel disease.
Abstinence or moderation? Choice by alcoholics.

Abstract Volunteer chronic alcoholics were given access to substantial quantities of alcohol in situations in which a behavioral contingency was attached to non-excessive drinking. If subjects either abstained or drank moderately they earned the opportunity to participate in an ‘enriched’ ward environment—with greater social and recreational opportunities. Subjects overwhelmingly chose to drink moderately. The results indicate that alcoholics can stop drinking after having begun, and thus support the hope that a technology may be developed for teaching moderation as a treatment goal. The results also suggest that for alcoholics, moderate drinking is more reinforcing than abstinence. The possibility that the opportunity to drink moderately can be used as a reinforcer in treatment programs is discussed.
1381 HYPOXIA DISRUPTS THE NEWBORN LAMB'S RESPONSE TO HEMORRHAGE

We evaluated the effect of hypoxia on the response of unanesthetized lambs (age 2-10 days) to hemorrhage of 50% of their measured blood volume over 30 min. All 15 lambs breathed 5% CO2 beginning 15 min. before hemorrhage and continuing for 90 min. after. The 5 lambs in Group I breathed 21% O2 throughout, the 5 in Group II breathed 9% O2 for the 15 min. prior to hemorrhage and then 21% O2, and the 5 in Group III breathed 9% O2 throughout the experiment. Organ blood flow was determined by radioactive microsphere technique and HR, BP, Hct, PO2, PCO2 and pH were measured 20 min. before, immediately before, at 2/3 of, at the end of, and at 90 min. after the hemorrhage. Group I had 4 survivors, Group II had 1, and Group III had none. The mortality in Group III was significantly greater than that in Group I (p≤0.05 Fischer exact). During the hemorrhage, BP and Hct fell similarly in all groups. In Group I, brain blood flow rose progressively throughout the experiment. In Group III, it rose with onset of hypoxia and then fell progressively thereafter. In Group II, it ran an intermediate course rising with the onset of hypoxia and then falling to baseline where it remained until shortly before death. Multiple regression analysis revealed a positive regression of brain blood flow on BP in Group III. We conclude that hypoxia during hemorrhage increases mortality and disrupts cerebral autoregulation.
THE ROBUSTNESS OF THE ANALYSIS OF VARIANCE AND THE TUKEY WSD TEST UNDER VARIOUS PATTERNS OF HETEROGENEOUS VARIANCES

The WSD and F tests show the same response when the homogeneous variance assumption is violated. Both are robust when the ns are equal, but may be either seriously conservatively biased or seriously permissively biased when heterogeneous variances are combined with unequal ns. The use of equal ns is recommended for either test. There is no virtue in insisting that the F test be significant prior to conducting the WSD when the alternative to the null is μi ≠ μj. However, the conservative bias created by this procedure is small when K = 4; as is the permissive bias created by conducting both tests. For uniformly distributed μ’s, the two tests have very similar powers. This condition would not be expected for different arrangements of the μ’s.
The assay of acid sites on zeolites as measured by ammonia poisoning

Abstract The decomposition of neopentane was studied with and without selective site poisoning with NH3. The lethal dose, which was just sufficient to kill the catalytic activity, was estimated for each of a series of H-mordenites, HY and HZSM-5 zeolites, all with Si Al ratios higher than 7.0, i.e., over silica-rich compositions where ideally all the sites are supposedly identical. It was found that poisoning no more than 10% of the sites (counted as lattice aluminum ions) was sufficient to eliminate the activity. Some ramifications of these observations are discussed. Unpoisoned and partially poisoned zeolites were investigated using 13C-MASNMR following adsorption of isopropanol-2-13C. These findings clearly show the efficacy of adsorbed NH3 in repressing formation of polymeric surface residues.
Phosphatidylinositol 4,5-bisphosphate: Light-mediated breakdown in the vertebrate retina

Abstract Isolated frog ( Rana Pipiens ) retinas were labeled in the dark with either [32P]PO4-orthophosphate or myo -[2-3H]inositol for 2.5–4 hrs. After washing the retinas with cold buffer, they were exposed to brief flashes of light (5 secs or 15 secs) and their rod outer segments isolated. Upon separation of labeled phospholipids, a specific decrease in label in phosphatidylinositol 4,5-bisphosphate was observed, whereas there was no significant effect on the labeling of phosphatidylinositol 4-phosphate, phosphatidylinositol, or phosphatidic acid. These results are indicative of a light-activated phosphatidylinositol 4,5-bisphosphate-specific phospholipase C in frog rod outer segments.
A computer-based data analysis system for enzyme-linked immunosorbent assays

A computerized system is presented for automating the data collection, processing, and displaying tasks involved in enzyme-linked immunosorbent assays. This system uses a through-the-well absorbance reader of microtiter plates interfaced to a minicomputer running the UNIX operating system. Optical density in each well of a 96-well microtiter plate is recorded as a function of time for up to 10 time points. These data are automatically transmitted to the remote computer. The rate of product formation is then calculated for each well, and a battery of analysis, display, and comparison programs can then be used by the researcher for data presentation. Using the initial rate of reaction as the basis for quantifying enzyme-linked immunosorbent assays focuses on the catalytic property of the enzyme and allows a large dynamic range of the assay on any plate. These programs can be adapted to virtually any mini- or microcomputer with a graphics display or a plotting device. Assuming moderately powerful computing hardware, throughputs of 50 plates per day are easily achieved. The programs work equally well with peroxidase, beta-galactosidase, or alkaline phosphatase conjugated second antibodies, and with whole cell or soluble antigens.
(K, j)-domination and (K, j)-reliability

The (K, j)-reliability of a K-terminal network G is the probability that after the failure of some of its edges the vertices in K will lie in no more than j connected components of the resulting subnetwork of G; when j = 1, this is the usual K-terminal reliability of G. In this paper, we extend the well-known theory of reliability domination and its application to the analysis of factoring algorithms for the computation of K-terminal reliability to (K,j)-reliability and the associated notion of (K, j)-domination. We give conditions equivalent to two edges being parallel or in series with respect to (K,j)-reliability, and we characterize the networks of (K,j) -domination ≤ 3.
Lack of concern deepens the oceans' problems.

Research has exposed flaws in marine conservation, yet little is written and less is cited.
CREDENTIALING CERTIFIED NURSE-MIDWIVES

As the U.S. health care system struggles to respond to demands for accessible, quality, sensitive, and cost-effective care, the contribution of nurse-midwives is receiving renewed attention. Many institutions are seeking assistance as they move to credential certified nurse-midwives for the first time or as they reassess their credentialing policies and procedures. This article provides an extensive review of multiple issues relating to credentialing nurse-midwives including nurse-midwifery education, licensure, scope of practice, professional liability, relationship with physicians, and delineation of privileges. The article also reviews Medicare Hospital Conditions of Participation and Joint Commission on Accreditation of Healthcare Organizations requirements as they relate to nurse-midwifery practice.
Lyman‐α absorption photometry at high pressure and atom density kinetic results for H recombination

Atomic absorption and fluorescence spectrophotometry have been routinely used in kinetic investigations as probes of relative, rather than absolute, atom concentration. The calibration of a Lyman-α photometer for measurement of absolute hydrogen atom concentrations at levels [H] ι ≤ 1.8 × 1014 atoms/cm2 and total pressure of 1.5 torr He is described. The photometer is characterized in terms of a two-level emission source and an absorption region in which only Doppler broadening of the transition is considered. The modifications due to pressure broadening by high pressures (500 ≤ P ≤ 1500 torr) in the absorption region are discussed in detail. Application of the technique is reported for the recombination of hydrogen atoms in the presence of six nonreactive heat bath gases. Experiments were performed in a static reaction cell at pressures of 500–1500 torr of heat bath gas, and hydrogen atoms were produced by Hg (3P1) photosensitization of H2. The technique is critically evaluated and the mechanistic implications of the hydrogen atom recombination results are examined. The measured room temperature recombination rate constants in H2, He, Ne, Ar, Kr, and N2 are 8.5 ± 1.2, 6.9 ± 1.5, 5.9 ± 1.5, 8.0 ± 0.8, 10.2 ± 0.9, and 9.6 ± 1.4, respectively, where the units are 1033 cm6/molec2 · sec.
Variations in Alkaloid Content of Herbal Products Containing Goldenseal

Objective To determine the concentration of hydrastine and berberine, the primary alkaloids in herbal products containing goldenseal. Design Descriptive comparison of 20 products purchased at local pharmacies or health food stores; 17 products were labeled as containing goldenseal root and 3 products contained goldenseal herb as the sole active herbal ingredient. Setting Laboratory assessment of alkaloid content using high-performance liquid chromatography. Main Outcome Measures Comparisons of hydrastine and berberine concentration, alkaloid ratio, and total alkaloid content among products. Results Hydrastine concentration in products labeled as containing goldenseal root ranged from 0 to 2.93%, whereas berberine concentration varied from 0.82% to 5.86%. Median total alkaloid concentration was 5.30%. Only 10 of 17 products met proposed United States Pharmacopeia (USP) standards for the hydrastine and berberine content of goldenseal root. Five products contained little or no hydrastine, unusual berberine: hydrastine ratios, and additional peaks not observed with other products. Alkaloid content in goldenseal root products was about fourfold higher than in products labeled as containing goldenseal herb. Conclusion Alkaloid content of goldenseal products varies widely, with many products failing to meet proposed USP standards. In addition, the Chromatographie pattern and alkaloid ratio for several products were atypical for goldenseal. Given the current absence of regulation of the quality of herbal products, pharmacists should take extra care to ensure that substandard goldenseal products are not sold in their pharmacies.
Willingness-to-pay stated preferences for 8 health-related quality-of-life domains in psoriatic arthritis: a pilot study.

Objectives Psoriatic arthritis (PsA) is a seronegative inflammatory arthritis found in up to 5 to 42% of patients with psoriasis. As current instruments do not fully capture health-related quality of life (HR-QOL) in PsA from the patient's perspective, we piloted a novel application of “willingness-to-pay” (WTP) as a Patient Reported Outcome to measure the relative impact of PsA in 8 domains of HR-QOL. Methods Fifty-nine PsA patients were interviewed on 8 WTP HR-QOL domains (physical, emotional, sleep, work, social, self-care, intimacy, and concentration). Participants were asked to rank the 8 domains of health in order of HR-QOL impact. In each domain, participants were asked whether PsA affected that domain, whether they were willing to pay for a cure in that domain, and the amount they were willing to pay. Median WTP amounts were compared with the proportion of participants affected by and willing to pay in each domain. Responses in US dollars were interpreted as strength of preference rather than absolute monetary values. Results The majority of participants were white (98%), ≥45 years of age (70%), insured (98%), and earned >$65,000/yr (66%). The physical domain was most affected by PsA; intimacy and concentration were ranked lowest. Participants reported a wide range of WTP amounts ($0 to $1,000,000), and median WTP amounts were highest in the physical, work, sleep, and self-care domains. Related domains elicited median WTP amounts that were highly correlated. No significant differences in median WTP amounts were found across ages, genders, and income levels for the different domains. Conclusions WTP is a novel quantitative patient-perspective measure that is comprehensible and feasible to administer in PsA patients. It represents a unique tool for capturing the complex manifestations of PsA and its impact on the individual, allowing the quantification of specific HR-QOL parameters and providing the potential for comparison across various disease processes in a given individual.
Kinetic and mechanistic characterization of the polyhydroxybutyrate synthase from Ralstonia eutropha.

Purified Ralstonia eutropha polyhydroxybutyrate (PHB) synthase from recombinant cells can exist as monomer and dimer. The polymerization reaction catalyzed by this enzyme displays a lag phase, which causes difficulties for kinetic and mechanistic characterization of the enzymatic polymerization reaction. In this study, we developed a method to eliminate the lag phase of PHB synthase by physical means, i.e., adding multihydroxyl compounds to the enzyme solution. This method allows us to recognize the nature of the lag phase as a physical rather than a chemical process. With such lag-phase-free-enzyme, the kinetic properties of the enzyme were investigated. The results indicate that 3-hydroxybutyryl-CoA (3HBCoA) is the optimal substrate for the enzyme. A slower catalytic rate and lower binding ability account for a lower reactivity of 3-hydroxyvaleryl-CoA (3HVCoA) compared to that of 3HBCoA. The change of hydroxyl group from the beta to the gamma position causes dramatic decreases in the binding ability of 4-hydroxybutyryl-CoA (4HBCoA). By using a dilution strategy and size exclusion chromatographic technique, the active form of the enzyme was identified to be the dimeric form. The number of catalytic sites in the dimeric form of the enzyme was examined by comparing the molecular weight of polyhydroxybutyrate as a function of substrate-to-enzyme ratio. The results suggest that the dimeric enzyme has only one catalytic site. A revised model of polymerization reaction catalyzed by R. eutropha PHB synthase is described.
The interactive effects of caffeine, impulsivity and task demands on a visual search task

Humphreys and Revelle (1983) have suggested that arousal hinders short-term memory processes but facilities attentional processes. In a conceptual replication of a study of body temperature and performance (Folkard et al., 1976), 84 undergraduates classified as low or high impulsive were given either caffeine or placebo. Two versions of a visual search task, one with a 2-letter target (a low memory load task) and one with a 6-letter target (a high memory load task), were used. As predicted, caffeine differentially affected the two tasks: subjects given caffeine detected a lower proportion of 6-letter targets but a greater proportion of 2-letter targets than did subjects given placebo. An unexpected interaction between Impulsivity, Task Sequence and Target Size suggested that high and low impulsives may have adopted different strategies or may have experienced different motvational states during the course of the experiment. The relevance of these data to Easterbrook's (1959) explanation of the Yerkes-Dodson effect is also discussed. These results are consistent with the assumption that there is an arousal dimension which is common to both caffeine and body temperature, and that this dimension is central to the observed pattern of performance.
Addition of Difluorocarbene to 4‘,5‘-Unsaturated Nucleosides: Synthesis and Deoxygenation Reactions of Difluorospirocyclopropane Nucleosides1

Synthetic routes to 4‘-(2,2-difluorospirocyclopropane) analogues of adenosine, cytidine, and uridine are described. Treatment of 2‘,3‘-O-isopropylidene-4‘,5‘-unsaturated compounds derived from adenosine and uridine with difluorocarbene (generated from PhHgCF3 and NaI) gave diastereomeric mixtures of the 2,2-difluorospirocyclopropane adducts. Stereoselectivity resulting from hindrance by the isopropylidene group favored addition at the β face. Removal of base and sugar protecting groups gave new difluorospirocyclopropane nucleoside analogues. The protected uridine analogue was converted into its cytidine counterpart via a 4-(1,2,4-triazol-1-yl) intermediate. Stannyl radical-mediated deoxygenation of the 3‘-O-TBS-2‘-thionocarbamate derivatives gave the 2‘-deoxy products of direct hydrogen transfer. In contrast, identical treatment of the 2‘-O-TBS-3‘-thionocarbamate isomers resulted in opening of the vicinal difluorocyclopropane ring upon generation of a C3‘ radical followed by homoallylic hydrogen transfer ...
Remarks on introductory syntax

L'A. analyse, dans cette etude critique d'articles traitant de la grammaire generative, quels sont les notions et les besoins primordiaux pour un cours introductif a la syntaxe, autant pour l'etudiant debutant que l'enseignant. Les quatre articles passes en revue sont les suivants: Peter Culicover Principles and parameters: an introduction to syntactic theory (1997); James D. Mc Cawley The syntactic phenomena of English (1998); Syntactic theory and the structure of English: a Minimalist approach (1997); Ian Roberts Comparative syntax (1997). La critique de l'A. repose sur les manques de ces articles dans leur interpretation et leur presentation de la syntaxe, qui porte atteinte au cote pedagogique et introductif desdits travaux.
Parallel distributed processing models for economic systems and games

This paper develops the idea that neural networks and other parallel models of computation provide a natural way in which to model the working of an economic system. Conversely, computational models implicit in descriptions of economic and social systems can provide us with very general methods and techniques which could be useful in other applications using neural networks. In general, both these research areas share a common concern with the problem of computation in parallel networks.
Potassium and sodium content of guinea-pig ureteral muscle

Abstract 1. 1. Guinea-pig ureteral smooth muscle showed the following figures (per kg wet tissue): water content, 0·835 ± 0·007. (n = 10); inulin space, 0·461 ± 0·271. (n = 10); K+ content, 59·3 ± 2·0 m-mole (n = 10); and Na+ content, 81·3 ± 2·2 m-mole (n = 20). Estimated intracellular concentrations were K+, 154 m-mole/1 and Na+, 33 m-mole/1. 2. 2. Resting potentials determined under normal and modified conditions were less than the values which would be expected from a pure potassium electrode. 3. 3. Radioisotope studies confirmed the ionic distribution and inhibitory action of ouabain on K+ uptake.
The neurochemical mechanism of rebound psychosis in Parkinson's disease.

A reply to this letter has been published in Movement DisordersMov Disord (2005) 20 (4) 515.
Continuous dependence on initial geometry for a class of abstract equations in Hilbert space

Abstract Conditions are given under which members of a class of uniformly bounded solutions to the Cauchy problem associated with equations of the form Mutt − Nu = F, in Hilbert space, depend continuously on perturbations of the initial geometry; our results generalize a similar theorem of Knops and Payne for classical solutions to initial-boundary value problems in linear elastodynamics.
Web search for a planet: The Google cluster architecture

Amenable to extensive parallelization, Google's web search application lets different queries run on different processors and, by partitioning the overall index, also lets a single query use multiple processors. to handle this workload, Googless architecture features clusters of more than 15,000 commodity-class PCs with fault tolerant software. This architecture achieves superior performance at a fraction of the cost of a system built from fewer, but more expensive, high-end servers.
Covalent carcinogenic guanine-modified DNA lesions: solution structures of adducts and crosslinks

Abstract The guanine base in DNA duplexes is a target for covalent adduct and crosslink formation with a range of mutagens and carcinogens. The structures of these DNA lesions have been elucidated by combining NMR and structure reconstruction methodologies on each adduct in a defined sequence context at the DNA oligomer level. Solution structures are available on benzo[a]pyrene diol epoxide, sterigmatocystin and aminofluorene adducts, intrastrand cis -platinum bifunctional adducts and interstrand mitomycin crosslinks. These structures define a range of DNA conformational perturbations at the lesion site and provide insights into the role of chiral functional groups on the carcinogen in determining its alignment along the DNA helix. These structures also exhibit a range of intermolecular stacking, hydrogen-bonding and hydrophobic interactions that stabilize the lesion-DNA interface. The structural data can be correlated with the available spectrum of mutational and carcinogenic activities associated with these lesions.
Mouse Models of Age-related Mitochondrial Neurosensory Hearing Loss

Hearing loss is the most common sensory disorder in the elderly population. Overall, 10% of the population has a hearing loss in the US, and this age-related hearing disorder is projected to afflict more than 28 million Americans by 2030. Age-related hearing loss is associated with loss of sensory hair cells (sensory hearing loss) and/or spiral ganglion neurons (neuronal hearing loss) in the cochlea of the inner ear. Many lines of evidence indicate that oxidative stress and associated mitochondrial dysfunction play a central role in age-related neurodegenerative diseases and are a cause of age-related neurosensory hearing loss. Yet, the molecular mechanisms of how oxidative stress and/or mitochondrial dysfunction lead to hearing loss during aging remain unclear, and currently there is no treatment for this age-dependent disorder. Several mouse models of aging and age-related diseases have been linked to age-related mitochondrial neurosensory hearing loss. Evaluation of these animal models has offered basic knowledge of the mechanism underlying hearing loss associated with oxidative stress, mitochondrial dysfunction, and aging. Here we review the evidence that specific mutations in the mitochondrial DNA or nuclear DNA that affect mitochondrial function result in increased oxidative damage and associated loss of sensory hair cells and/or spiral ganglion neurons in the cochlea during aging, thereby causing hearing loss in these mouse models. Future studies comparing these models will provide further insight into fundamental knowledge about the disordered process of hearing and treatments to improve the lives of individuals with communication disorders. This article is part of a Special Issue entitled 'Mitochondrial function and dysfunction in neurodegeneration'.
Relationships Between Moral Disengagement, Work Characteristics and Workplace Harassment

This study was undertaken to investigate whether work variables identified in theory and research as being related to employee experiences/behaviours add to the understanding and explain employees’ experiences of workplace harassment. The extent to which social cognitive theory (SCT), specifically moral disengagement, explains the processes by which work characteristics are related to harassment was also examined. The purpose of the study was to identify the presence of relationships among work characteristics, satisfaction, moral disengagement and workplace harassment. According to the results, employees with negative opinions of their work tended to experience negative affect and to believe that it is acceptable to harm others. The results of this study provide evidence of (1) relationships between harassment and several workplace characteristics and (2) the applicability of SCT to the explanation of how work characteristics relate to harassment.
Prenatal diagnosis of fetal urinary tract abnormalities by ultrasound

The prenatal detection of renal enlargement and sonolucent “cystic” lesions in 4 fetal abdomens by ultrasound is described. These were later proved to be congenital urinary tract anomalies. Only one of the other 4,628 mothers who had ultrasound gave birth to a child with a congenital urinary tract anomaly that was missed, and 1 fetus was falsely diagnosed as having a congenital urinary tract anomaly based on the ultrasound. Obstruction in the developing urinary tract is associated with renal dysplasia and insufficiency. More experience and improved ultrasonography may enable an accurate diagnosis of urinary tract obstruction; and early relief of the obstruction may be a possible method of management to minimize the renal damage.
Introduction to the Special Issue on Immigration: Expanding Definitions and Examining New Contexts

Despite being a nation of immigrants, the United States has long struggled with the issue of immigration. Since before the nation's founding, the country's immigration policies and practices have b...
Resistance of Trypanosoma cruzi to killing by macrophages.

CHAGAS' disease is a chronic debilitating illness, widespread in Latin America, caused by infection with the haemoflagellate, Trypanosoma cruzi. Antibodies to the organism, commonly present in both the acute and chronic forms of the disease, have generally been ineffective in protecting animals against infection1,2. There is ample pathological documentation of the involvement of macrophages in Chagas' disease3–5 but unfortunately little is known about their function, or of the role of cell-mediated immunity in general. It has, however, been shown that passive transfer of immune spleen cells can protect mice against T. cruzi infection1. Because macrophages serve as effector cells in protecting against intracellular parasites, we have studied the interaction of T. cruzi and macrophages in vitro. Preliminary experiments showed that at low parasite–macrophage ratios (for example 1) most cultures of normal uninduced mouse peritoneal macrophages could eliminate the infection and survive; in contrast, with higher ratios (for example 10), they were destroyed6. Mackaness7 has shown that macrophages can be ‘activated’ after immunisation and challenge with specific antigen to become non-specifically resistant to other infecting bacteria. We report here that nonspecifically ‘activated’ macrophages have heightened resistance to intracellular growth of T. cruzi, and suggest that its absence in normal macrophages is related to the ability of the parasite to escape from the phagolysosomes into the cytoplasm.