cssi/SciSciGPT-SciSciNet huggingface dataset:
IMAGE MAGNIFICATION IN DIGITAL FLUOROSCOPY

Image magnification is inherent in radiography. In digital fluoroscopy, the three components of magnification are geometric, electronic and photographic. In this study, the total magnification factor of a digital imaging system was determined by two methods, 1) comparison of measurements of a known object to its image and 2) calculation of geometric, electronic and photographic magnification from the imaging system specifications. Both methods were employed for various focal-film distances, image intensifier tube modes and laser printer formats. Results of these two methods were different due to the detrimental effect of penumbra on image quality with increasing magnification. If a radiographic image is to be used to approximate object size, then a technique should be used that will minimize magnification. In digital fluoroscopy this is achieved with the shortest object-film distance (assuming a fixed focal-object distance), largest image intensifier mode and greatest number of images per sheet of film.
Children Living in Poverty: Their Perception of Career Opportunities:

Growing up in poverty often diminishes a child's opportunity to pursue a rewarding career path. This qualitative study explored whether poor children are aware that their wealthier peers' chances for success may be greater than their own. Projective techniques employing photographs of two houses representing poor and middle-income families were used to interview twenty-four children between the ages of five and thirteen years, divided equally between white and African Americans. These respondents perceived that society provides better future job opportunities to nonpoor children while limiting those of the poor. Although respondents suggested that they and their friends could be exceptions to these limitations, indications of their beginning feelings of hopelessness were revealed. The author proposes strategies to assist in strengthening poor children's belief in themselves and their future.
Determination of benzylpenicillin in pharmaceuticals by capillary zone electrophoresis

Abstract A rapid and direct method is described for the determination of benzylpenicillin (penicillin G) in pharmaceutical preparations. the method involves very little sample preparation and total analysis time for duplicate results is less than 30 minutes per sample. The method takes advantage of the speed and separating power of capillary zone electrophoresis (CZE). Detection of penicillin is by absorption at 228 nm. an internal standard is employed to reduce sample injection error. the method was applied successfully to both tablets and injectable preparations. larger on longer aging. It was the authors' hypothesis that this peak was due to formation of penicilloate. When this degradation product was synthesized according to an established procedure14, CZE retention time of the synthesized product was the same as that final peak in the aged penicillin samples. UV spectra on both solutions was further evidence we had properly identified the degradation product. Thus the relative amount of active and de...
Lithium treatment restores clonidine's effect in an animal model of depression

Abstract IP administration of various doses of clonidine produces significant increases in growth harmone levels in the Wistar rats but not in the Fawn-Hooded (FH) rats, a rat strain suggested to be a genetic model of depression. However, short-term lithium treatment restores clonidine's effect on growth hormone levels in the Fawn-Hooded rats. Potentiation of clonidine's effect on growth hormone levels following short-term lithium treatment appears most likely due to increased serotonergic function as a consequence of enhanced 5-HT concentrations at postsynaptic 5-HT1C receptor sites. Thus, the reversal of a deficit state in Fawn-Hooded rats by lithium treatment supports earlier studies suggesting this rat strain to represent a genetic model of depression.
Analysis of enhanced two-photon absorption in tapered optical fibers

We analyze the rate of two-photon absorption in tapered optical fibers with diameters less than the wavelength of the incident light. The rate of two-photon absorption is shown to be enhanced due to the small mode volume of the tapered fiber and the relatively large overlap of the evanescent field with an atomic vapor that surrounds the tapered region. The two-photon absorption rate is optimized as a function of the diameter of the tapered region.
PROBABILISTIC ANALYSIS OF THE EFFICACY OF PERIODIC TESTING OF EMPLOYEES

Some major companies have the policy of annually giving numerical scores to their employees according to their performance, firing those whose performance scores are below a given percentile of the scores of all employees, and then recruiting new employees to replace those who were fired. We introduce a probabilistic model to describe how this practice affects the quality of employee performance as measured over time by the annual scores. Let n be the number of years that the policy has been in effect, and let F n (x) be the distribution function of the evaluation scores in year n. We show, under certain technical assumptions, that the sequence (F n (x)) satisfies a particular nonlinear difference equation, and furnish estimates of the solution of the equation and expressions for the quantiles of F n . The mathematical tools that are used include convex functions, difference equations, and extreme value theory for independent and identically distributed random variables.
The phospholipids of liver, plasma, and red cells in normal and cholesterol-fed anemic guinea pigs.

SummaryThe PL classes and their fatty acid compostion were determined in liver, plasma, and RBC from normal and C-fed anemic GP. Compared to other species, guinea pig RBC had low amounts of Sph and high amounts of PC. Most PL of GP had very low levels of 20:4 and lower ratios of 20:4/18:2 and 16:0/18:0 than those of rats and other species which are less susceptible to injury by excess dietary cholesterol. The following changes have been observed in the C-fed anemic GP: Increased proportions and amounts of lyso-PC in the three tissues compensated by nearly equivalent decreases of PC; increased proportions of Sph in liver and plasma; decreased proportions of Sph in RBC accompanied by an increase of PC/Sph ratio; and increased amounts and proportions of PC-20:4 in RBC and PI-20:4 of liver. The possible significance of these changes for the development of the anemia have been discussed.
Abnormal keratinization in the pupoid fetus (pf/pf) mutant mouse epidermis.

Abstract During its development the epidermis of the pf pf mutant mouse is invaded by cells from the underlying dermis. These invading cells establish a network of cells including fibroblasts, endothelial cells, and nerve fibers, throughout the epidermis. Subsequent to these events the keratohyalin protein, filaggrin, is drastically reduced and keratinization fails to occur. Heterotypic tissue recombinations indicate that the pf gene is not expressed in the skin. After simply grafting whole mutant dorsal skin, filaggrin synthesis is initiated and an orderly process of epidermal differentiation is achieved. These results suggest that the pf gene acts systemically and that the failure of epidermal differentiation in the mutant occurs secondary to abnormal epidermal organization.
STRUCTURAL CHANGES IN LABOR DEMAND AND UNEMPLOYMENT IN LOCAL LABOR MARKETS

ABSTRACT. It seems quite clear that the US. economy in the late 1970s and early 1980s was exposed to an accelerated rate of structural change resulting from energy price shocks, increased international competition and technological change. It is of considerable interest, then, that previous attempts to examine structural unemployment in this period find that structural shift in employment generally were not Significant determinants of the unemployment rate. This paper revisits this issue using a measure of structural job shifts drawn from the literature on establishment job creation and destruction. The results show that changes in the structure of labor demand across industry by establishment-size sectors had a statically significant and empirically important positive effect on the unemployment rate in a sample of 200 metropolitan labor markets during the 1976 to 1984 period.
Race, care seeking, and utilization for chronic back and neck pain: population perspectives.

Abstract We analyzed a statewide survey of individuals with chronic back and neck pain to determine whether prevalence and care use varied by patient race or ethnicity. We conducted a telephone survey of a random sample of 5,357 North Carolina households in 2006. Adults with chronic (>3 months duration or >24 episodes of pain per year), impairing back or neck pain were identified and were asked to complete a survey about their health and care utilization. 837 respondents (620 white, 183 black, 34 Latino) reported chronic back or neck pain. Whites and blacks had similar rates of chronic back pain. Back pain prevalence was lower in Latinos (10.4% [9.3–11.6] vs 6.3% [3.8–8.8]), likely due to their younger age; and the prevalence of chronic, disabling neck pain was lower in blacks (2.5% [1.9–3.1] vs 1.1% [.04–1.9]). Blacks had higher pain scores in the previous 3 months (5.2 vs 5.9 P P Perspective This article presents new, population-based data on the issue of racial and ethnic disparities in neck- and back-pain prevalence and care. Few disparities were found; care quality issues may affect all ethnic groups similarly. Previous findings of disparities in chronic-pain management may be decreasing, or may perhaps be site specific.
Estimation of instantaneous frequency using the discrete Wigner distribution

Analytical expressions for the performance of the discrete Wigner distribution (DWD) in estimating the instantaneous frequency of linear frequency modulated signals in additive white noise are derived and verified using simulation. It is shown that the DWD peak provides an optimal estimate at high input signal-to-noise ratios. The applicability of these results to the general case of nonlinear FM signals is discussed.
Mechanisms of dispersed central-place foraging in polydomous colonies of the Argentine ant.

Many species of ants occupy multiple nests, a condition known as polydomy. Because of their decentralized structure, polydomous colonies may be removed from some of the constraints associated with classic central-place foraging. We used laboratory and field experiments to assess the mechanisms involved in dispersed central-place foraging in polydomous colonies of the Argentine ant Linepithema humile, a widespread invasive species. Both in the laboratory and in the field, Argentine ants established new nests at sites located near food. Laboratory colonies of L. humile redistributed workers, brood and resources among nests in response to the spatial heterogeneity of food resources. In addition, laboratory colonies formed recruitment trails between nests in the context of foraging, providing a mechanism for the transport of material between nests. This highly flexible system of allocating nests, workers and brood throughout a colony's foraging area potentially increases foraging efficiency and competitive ability. The importance of polydomy as a determinant of competitive ability is underscored by its prevalence among ecologically dominant ants, including most, if not all, highly invasive species.
Damage control resuscitation: a sensible approach to the exsanguinating surgical patient.

Background:The current wars in Iraq and Afghanistan have resulted in the highest rates of combat casualties experienced by the U.S. military since the Vietnam conflict. These casualties suffer wounds that have no common civilian equivalent and more frequently require massive transfusion (greater tha
Consumer Responses to Fashion Advertisements Using Models in Wheelchairs: Is There a Relationship to Consumers' Optimum Stimulation Level?

This study examines consumer responses tofashion advertisements using 2 advertising stimuli (model in wheelchair/lawn chair). Further, because models in wheelchairs are unusual stimuli, the effect of consumers' Optimum Stimulation Level (OSL) on responses to the advertising stimuli is explored. In an experiment using stimulus sampling, 101 working women viewed a fashion advertisement featuring 1 of 3 models in a wheelchair or a lawn chair and rated the likelihood that they would inquire about, would consider purchasing, and would actually purchase advertised items. There were no significant effects for OSL, social desirability, or individual models on consumer responses. Consumers were more likely to inquire about, more likely to consider purchasing, and more likely to actually purchase the clothing items presented by a model in a wheelchair. Results have implicationsfor OSL theoryfashion marketers targeting working women, models in wheelchairs, and society as a whole.
Is the vasoactive intestinal peptide (VIP) a prohormone

Abstract The possibility that the vasoactive intestinal peptide (VIP) is a prohormone, which through enzymic fragmentation gives rise to shorter chains with, yet unknown, hormonal activities is suggested by the occurrence of two pairs of adjoining basic residues in its sequence. (A similar pattern can be recognized in proinsulin.) Synthesis of one of the hormone-candidates, l -pyroglutamyl- l -methionyl- l -alanyl- l -valyl- l -lysyl- l -lysyl- l -tyrosyl- l -leucyl- l -asparaginyl- l -seryl- l - valyl- l -leucyl- l -threoninamide corresponding to the C-terminal 13-peptide sequences of chicken VIP is reported.
Perceived susceptibility to pregnancy and its association with safer sex, contraceptive adherence and subsequent pregnancy among adolescent and young adult women.

Abstract Background The study was conducted to examine the hypotheses that adolescent and young adult women who perceived they are susceptible to pregnancy when birth control is not used are less likely to practice unsafe sex, discontinue oral contraception (OC) and become pregnant during a 12-month follow-up period. Study Design We conducted secondary analyses using data collected for a randomized controlled trial on OC adherence among 1155 low-income women 16–24 years of age. Demographics, lifestyle variables, perceived susceptibility to pregnancy assessed at baseline, and data on OC and condom use and pregnancy status collected during 12 months of follow-up were used for the analyses. Results Overall, 62.3% of women accurately understood the risks of pregnancy without using any birth control method. However, perceived susceptibility was not associated with OC continuation [odds ratio (OR) 0.94, 95% confidence interval (CI) 0.79–1.11], condom use at last sexual intercourse (OR 1.02, 95% CI 0.84–1.24), dual method use (OR 1.17, 95% CI 0.92–1.48) and subsequent pregnancy (hazards ratio 1.08, 95% CI 0.77–1.49) during the 12-month follow-up period. Conclusions Perceived susceptibility to pregnancy, an important component of the health belief model, does not seem to have any impact on use of birth control methods, safer sex or rate of subsequent pregnancy among low-income adolescent and young adult women.
A Four PDZ Domain-containing Splice Variant Form of GRIP1 Is Localized in GABAergic and Glutamatergic Synapses in the Brain

We have isolated, from a rat brain cDNA library, a clone corresponding to a 2779-bp cDNA encoding a novel splice form of the glutamate receptor interacting protein-1 (GRIP1). We call this 696-amino acid splice form GRIP1c 4-7 to differentiate it from longer splice forms of GRIP1a/b containing seven PDZ domains. The four PDZ domains of GRIP1c 4-7 are identical to PDZ domains 4-7 of GRIP1a/b. GRIP1c 4-7 also contains 35 amino acids at the N terminus and 12 amino acids at the C terminus that are different from GRIP1a/b. In transfected HEK293 cells, a majority of GRIP1c 4-7 was associated with the plasma membrane. GRIP1c 4-7 interacted with GluR2/3 subunits of the α-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid receptor. In low density hippocampal cultures, GRIP1c 4-7 clusters colocalized with GABAergic (where GABA is γ-aminobutyric acid) and glutamatergic synapses, although a higher percentage of GRIP1c 4-7 clusters colocalized with γ-aminobutyric acid, type A, receptor (GABAAR) clusters than with α-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid receptor clusters. Transfection of hippocampal neurons with hemagglutinin-tagged GRIP1c 4-7 showed that it could target to the postsynaptic complex of GABAergic synapses colocalizing with GABAAR clusters. GRIP1c 4-7-specific antibodies, which did not recognize previously described splice forms of GRIP1, recognized a 75-kDa protein that is enriched in a postsynaptic density fraction isolated from rat brain. EM immunocytochemistry experiments showed that in intact brain GRIP1c 4-7 concentrates at postsynaptic complexes of both type I glutamatergic and type II GABAergic synapses although it is also presynaptically localized. These results indicate that GRIP1c 4-7 plays a role not only in glutamatergic synapses but also in GABAergic synapses.
A kinetic study of the polymerization of aliphatic imides

Thermal polymerization of a homologous series of aliphatic poly(methylene) citra-itaconimides was investigated by differential scanning calorimetry. Enthalpic analysis indicated that, at least to a major extent, the conversion reactions followed pseudo-first-order kinetics. A reasonably linear correlation between the number of sequential methylene groups (6, 8, 10, and 12), between the imide ring structures of the monomers, and the activation energy was observed. Reaction rates and initial temperatures of polymerization as well as thermal stability are compared to those of related poly(methylene)–biscitraconimides and –bismaleimides.
A hybrid model to calculate the forward delay time of heterojunction bipolar transistors

Abstract The forward delay time (τF) of heterojunction bipolar transistors (HBTs) is calculated using a hybrid model of carrier transport. A rigorous quantum-mechanical treatment of electron tunneling and thermionic emission across the spike at the emitter-base junction is used to determine the energy of the electron flux injected into the base region. This flux is used as an initial distribution in a regional Monte Carlo simulator to model electron transport from base to sub-collector. In this paper, we estimate the base transit time using the impulse response technique and the collector delay time using the expression of Laux and Lai (IEEE Electron Device Letters, 11, 174, 1990). Improvements to the hybrid model proposed here to reduce some of the discrepancies between measured and calculated values of ƒτ for some InAlAs/InGaAs and InP/InGaAs structures reported in the literature are discussed.
The pediatric acute scrotum

The pediatric acute scrotum can be a diagnostic dilemma. The history, physical examination, and appropriate tests are important. The correct diagnosis will be arrived at if the systematic approach is remembered (Figure 14). In cases where testicular torsion cannot be ruled out (such as an epididymitis or torsion of the appendix testis where torsion of the testis is mimicked), the patient will need scrotal exploration. It is hoped that with further availability of scanning and expertise by pediatric surgeons the false negative exploration will decrease in number. Remember, occasionally a patient will require scrotal exploration with biopsy of the epididymis to delineate the underlying cause. In most cases of epididymitis, effort should be made to identify the cause by culture of urine, urethral discharge, or appropriate fluid from the epididymis. Urological evaluation will be necessary in the younger boys, particularly those with recurrent episodes, to rule out congenital anomalies. Only by following this systematic approach can clinicians hope to preserve gonadal function and achieve best care of their patients.
Rifampicin and chloramphenicol effects on DNA replication in ultraviolet-damaged Escherichia coli B/r WP2 thy trp

Abstract The antibiotic rifampicin, which blocks specifically RNA synthesis, limited DNA replication in Escherichia coli strain B/r WP2 thy trp after an increase of about 50%, when added to the incubation medium at the time of replication initiation after ultraviolet fluences of 20 J/m 2 or 25 J/m 2 . Chloramphenicol, which blocks protein synthesis, did not limit DNA replication when added at, or any time after, initiation. The prolonged lag in DNA replication caused by ultraviolet was not itself responsible for the rifampicin limitation. When a lag of 30 min was caused by starvation for thymine, DNA was synthesized after readdition of thymine to an increase of 100% or more in rifampicin-containing medium. When chloramphenicol was added to an ultraviolet-exposed culture, the limiting effect of rifampicin alone was suppressed. This effect held even with a higher fluence (32.5 J/m 2 ), after which the ability to make DNA in the presence of rifampicin alone was slight. Maximum effect was obtained when the chloramphenicol was added to the ultraviolet-exposed, rifampicin-containing culture immediately before initiation of DNA replication. When rifampicin was present at a concentration of 150 μg/ml (2.2 · 10 −4 M), 3 μg/ml of chloramphenicol (9.2 · 10 −6 M) was as effective as 160 μg/ml (5.0 · 10 −4 M), thus eliminating the possibility that direct stoichiometric interaction of rifampicin and chloramphenicol molecules caused the effect.
Neutrality point of graphene with coplanar charged impurities.

The ground state and the transport properties of graphene subject to the potential of in-plane charged impurities are studied. The screening of the impurity potential is shown to be nonlinear, producing a fractal structure of electron and hole puddles. Statistical properties of this density distribution as well as the charge compressibility of the system are calculated in the leading-log approximation. The conductivity depends logarithmically on $\ensuremath{\alpha}$, the dimensionless strength of the Coulomb interaction. The theory is asymptotically exact when $\ensuremath{\alpha}$ is small, which is the case for graphene on a substrate with a high dielectric constant.
Drug-induced responses of canine vesical smooth muscle cells in culture

Vesical smooth muscle cells were grown in enzyme-dispersed cell culture, and contractions of single cells were induced by various exogenous neurotransmitters or analogues. This model may be suitable for studying the physiologic properties of smooth muscle cells in culture and thus cell differentiation and changes under defined conditions of culture. The effects of various drugs on single muscle cells may be compared: The pharmacologic effect on the muscle can thus be judged intrinsically without the interferences inherent in the natural milieu and from pharmacologic effects on the central or peripheral nervous system.
An appraisal of small and diminutive colonic polyps.

A retrospective review of all colonoscopic polypectomies performed in a busy surgical endoscopy unit over a 6-month period was undertaken. All patients were included who presented with colonic polyps measuring less than 1 cm in diameter for which sufficient specimens were available for histopathologic examination. In all, 262 were polyps removed from 206 patients; of these, 158 (60%) were neoplastic. There was a statistically significant predilection for polyps in the right colon to be neoplastic. Worrisome histologie patterns (severe dysplasia, carcinoma in situ, or invasive carcinoma) were seen in 18 specimens (6.5%). In two patients, polypoid carcinoma could be identified; in one case it involved a lesion measuring 0.2 cm in diameter. Since these lesions exhibit no distinctive gross features, only their endoscopie removal and histologie study can ensure proper diagnosis and treatment.
Novel fatty acid acylation of lens integral membrane protein aquaporin-0.

Fatty acid acylation of proteins is a well-studied co- or posttranslational modification typically conferring membrane trafficking signals or membrane anchoring properties to proteins. Commonly obs...
Functional Genomics of Serotonin Receptor 2A (HTR2A): Interaction of Polymorphism, Methylation, Expression and Disease Association

Serotonergic neurotransmission plays a key role in the pathophysiology of neuropsychiatric illnesses. The functional significance of a promoter polymorphism, −1438G/A (rs6311), in one of the major genes of this system (serotonin receptor 2A, HTR2A) remains poorly understood in the context of epigenetic factors, transcription factors and endocrine influences. We used functional and structural equation modeling (SEM) approaches to assess the contributions of the polymorphism (rs6311), DNA methylation and clinical variables to HTR2A expression in chronic fatigue syndrome (CFS) subjects from a population-based study. HTR2A was up-regulated in CFS through allele-specific expression modulated by transcription factors at critical sites in its promoter: an E47 binding site at position −1,438, (created by the A-allele of rs6311 polymorphism), a glucocorticoid receptor (GR) binding site encompassing a CpG at position −1,420, and Sp1 binding at CpG methylation site −1,224. Methylation at −1,420 was strongly correlated with methylation at −1,439, a CpG site that is dependent upon the G-allele of rs6311 at position −1,438. SEM revealed a strong negative interaction between E47 and GR binding (in conjunction with cortisol level) on HTR2A expression. This study suggests that the promoter polymorphism (rs6311) can affect both transcription factor binding and promoter methylation, and this along with an individual’s stress response can impact the rate of HTR2A transcription in a genotype and methylation-dependent manner. This study can serve as an example for deciphering the molecular determinants of transcriptional regulation of major genes of medical importance by integrating functional genomics and SEM approaches. Confirmation in an independent study population is required.
Analysis of wave propagation in a nonlinear strain-hardening medium☆

Abstract This paper is concerned with the propagation of plastic waves of uniaxial strain across an infinite, nonlinear, strain-hardening slab of finite thickness that is free at one surface and subjected, at the other, to a suddenly applied compressive stress, which thereafter is maintained constant or decreased monotonically to zero. In loading, the stress-strain diagram of the material for uniaxial strain is supposed to consist of a rectilinear segment followed by a curve that is convex toward the strain-axis. In unloading, the strain is supposed to remain constant (rigid unloading). General expressions for stress, strain and particle velocity are derived, together with the governing integro-differential equation for the shock path. Closed-form solutions are obtained for two cases. In the first, the suddenly applied stress is thereafter maintained constant, and the curved part of the stress-strain diagram for loading is described by a power law. In the second case, the suddenly applied stress is monotonically reduced to zero, and the stress-strain diagram for loading consists of two straight segments. Finally, a semi-inverse method for obtaining closed-form solutions is developed in which the applied stress is treated as a function of the shock path so that the determination of its explicit variation with time is a part of the solution of the problem.
Total Synthesis of Petrosin, Petrosin A, and Petrosin B

The petrosins are a family of marine alkaloids that includes the chiral, racemic isomer petrosin (1), the meso isomer petrosin A (2), and the chiral, scalemic isomer petrosin B (3). Monte Carlo molecular mechanics calculations indicated that petrosin (1) is the most stable isomer of the group, suggesting that it might be synthesized by a route that utilizes thermodynamic control for establishing the relative configurations of the eight stereocenters. The model synthesis summarized in Scheme 1 showed that intramolecular Mannich condensation is a viable route to the quinolizidone subunit of the petrosins and that this synthesis gives isomer 5, having the relative configuration found in petrosin and petrosin A, as the kinetic product. Equilibration studies with this isomer afforded an approximate equimolar mixture of 5 and diastereomer 6, having the relative configuration found in one of the two quinolizidone units of petrosin B. On the basis of this model study, a “stereo-uncontrolled” synthesis of petrosin...
Fracture toughness of a high-strength beryllium at room temperature and 300° C

The fracture toughness of a high yield strength grade of hot-pressed beryllium block was determined at room temperature and 300° C. Fatigue cracks were generated in doublecantilever beam specimens by a reversed loading method. Room temperature fracture toughness values from specimens with electric discharge machined notches fell within the scatter band of values from specimens with fatigued precracks. Load—displacement records generated from test on specimens with machined notches exhibited the expected linearity. However, the records were nonlinear from tests on specimens with long cracks formed by repeated propagation and arrest. Evidence points to a crack-closure phenomenon rather than plasticity as the source of the nonlinearity. The fracture toughness data show that specimen orientation or test temperature have little effect. By contrast, reported ductility values for this material are very sensitive to both these variables. The mean value of the fracture toughness ranged from 9.0 MPa m1/2 (8.1 ksi in. 1/2) at 23° C to 10.8 MPa m1/2 (9.7 ksi in. 1/2) at 300° C. These values are among the lowest ever reported for beryllium.
Effect of hydrostatic pressure on the HgTe optical phonon

Abstract We have measured the reflectivity from 20–240cm−1 of HgTe samples at 80 K and below as a function of hydrostatic pressure to 8 kbars. The transverse optical phonon frequency was determined from a Kramers-Kronig analysis of the data. For three samples of different doping levels we find dωTO/dp = 0.34 cm−1 kbar−1. The Gruneissen's parameter, γ = 1.2, is typical of values for zincblende crystals indicating that the phonon is not influenced by the narrow gap and inverted band structure. The defect oscillator at 107 cm−1 is observed to be independent of pressure. This appears inconsistent with its identification as a phonon difference mode.
PPMexe: Program compression

With the emergence of software delivery platforms, code compression has become an important system component that strongly affects performance. This article presents PPMexe, a compression mechanism for program binaries that analyzes their syntax and semantics to achieve superior compression ratios. We use the generic paradigm of prediction by partial matching (PPM) as the foundation of our compression codec. PPMexe combines PPM with two preprocessing steps: (i) instruction rescheduling to improve prediction rates and (ii) heuristic partitioning of a program binary into streams with high autocorrelation. We improve the traditional PPM algorithm by (iii) using an additional alphabet of frequent variable-length supersymbols extracted from the input stream of fixed-length symbols. In addition, PPMexe features (iv) a low-overhead mechanism that enables decompression starting from an arbitrary instruction of the executable, a property pivotal for runtime software delivery. We implemented PPMexe for x86 binaries and tested it on several large applications. Binaries compressed using PPMexe were 18--24p smaller than files created using off-the-shelf PPMD, one of the best available compressors
Regulation of rhodopsin-eGFP distribution in transgenic xenopus rod outer segments by light.

The rod outer segment (OS), comprised of tightly stacked disk membranes packed with rhodopsin, is in a dynamic equilibrium governed by a diurnal rhythm with newly synthesized membrane inserted at the OS base balancing membrane loss from the distal tip via disk shedding. Using transgenic Xenopus and live cell confocal imaging, we found OS axial variation of fluorescence intensity in cells expressing a fluorescently tagged rhodopsin transgene. There was a light synchronized fluctuation in intensity, with higher intensity in disks formed at night and lower intensity for those formed during the day. This fluctuation was absent in constant light or dark conditions. There was also a slow modulation of the overall expression level that was not synchronized with the lighting cycle or between cells in the same retina. The axial variations of other membrane-associated fluorescent proteins, eGFP-containing two geranylgeranyl acceptor sites and eGFP fused to the transmembrane domain of syntaxin, were greatly reduced or not detectable, respectively. In acutely light-adapted rods, an arrestin-eGFP fusion protein also exhibited axial variation. Both the light-sensitive Rho-eGFP and arrestin-eGFP banding were in phase with the previously characterized birefringence banding (Kaplan, Invest. Ophthalmol. Vis. Sci. 21, 395–402 1981). In contrast, endogenous rhodopsin did not exhibit such axial variation. Thus, there is an axial inhomogeneity in membrane composition or structure, detectable by the rhodopsin transgene density distribution and regulated by the light cycle, implying a light-regulated step for disk assembly in the OS. The impact of these results on the use of chimeric proteins with rhodopsin fused to fluorescent proteins at the carboxyl terminus is discussed.
Oxygen consumption rate in vascular smooth muscle: relation to isometric tension.

Abstract Advances in muscle energetics require knowledge of the rates of the driving chemical reaction. Vascular smooth muscle, 2–3 orders of magnitude slower than amphibian skeletal muscle, permits continuous measurement of reaction rates. Oxygen consumption rates in the steady state appear to be a valid measure of the rate of the driving chemical reaction. The relation between isometric force and oxygen consumption rate is linear, and thus consistent with nonequilibrium thermodynamic analysis.
Giving Advice: Enough Is Enough After Three Solar Cycles

On 1 July 2008, I concluded my 6-year term of service as president-elect, president, and past-president of AGU's Space Physics and Aeronomy (SPA) section. I truly appreciated the trust and confidence placed in me by the SPA electorate, and I greatly enjoyed this unique period of professional service. To have sufficient time to be fully engaged in SPA and AGU matters, I had taken a 6-year leave of service from advisory committees at NASA, the U.S. National Science Foundation, the Space Studies Board of the U.S. National Academy of Sciences (NAS), Department of Defense laboratories, and grant panels at all U.S. federal agencies.
Medical Records and Quality of Care in Acute Coronary Syndromes: Results From CRUSADE

Background Patient medical records are important means of communication among health care providers. Limited evaluation has been performed of the quality of the medical records or its association with health care processes or outcomes. Methods We performed an empirical evaluation of the completeness of medical records from 607 randomly selected patients admitted with non–ST-segment elevation acute coronary syndromes (NSTE ACS) to 219 US hospitals in the CRUSADE National Quality Improvement Initiative. Composite medical records scores were summated and compared by hospital academic status and physician specialty. Correlations between medical records scores, use of evidence-based medicine (EBM), and in-hospital mortality were assessed. Results Medical records were frequently missing key elements, including cardiac history (23.6%), performance status (64.6%), differential diagnosis (57.8%), and planned use of EBM (44.0%). Evidence-based medicine was more often discussed in medical records from academic medical centers vs nonacademic medical centers (69.7% vs 51.7%) (P Conclusions Medical records for patients with NSTE ACS often lack key elements of the history and physical examination. Patients treated at hospitals with better medical records quality have significantly lower mortality and may receive more EBM. The relationship between better medical charting and better medical care could lead to new ways to monitor and improve the quality of medical care.
NUTRITIONAL REQUIREMENTS OF PREGNANT AND LACTATING RATS STUDIED BY THE SELFSELECTION METHOD

In a previous study the self-selection technic was used to determine the nutritional requirements of normal animals (1,2). Pure substances rather than so-called natural foods or food mixtures were offered for choice. It was found that, given a selection of 11 substances in separate containers (casein, sucrose, olive oil, sodium chloride, dibasic sodium phosphate, calcium lactate, potassium chloride, dried baker's yeast, cod liver oil, wheat germ oil, and water), rats made selections which were conducive to excellent growth and normal reproduction. This self-selection technic has now been used to study the nutritional requirements during pregnancy and lactation.
Reply to ``Comment on `Surface silicon-deuterium bond energy from gas-phase equilibration'''

The free energy of binding of deuterium to a surface silicon atom is obtained directly from our previously reported experiment. However, comparison with first-principles calculations of the surface Si-D bond energy requires an estimation of the contribution to the free energy from the vibrational entropy ${\mathrm{S}}_{\mathrm{vib}}$. Herring and Van de Walle determine a value of 2.99 eV for the bond energy at 800 \ifmmode^\circ\else\textdegree\fi{}C from our data, using a harmonic oscillator model to estimate ${\mathrm{S}}_{\mathrm{vib}}$. Our method of estimating ${\mathrm{S}}_{\mathrm{vib}}$ from solubility measurements gives a lower Si-D bond energy of 2.49 eV. These values are both lower than the bond energy from Van de Walle's first-principles calculation. Uncertainties involved in comparing theory with experiment are discussed.
Ontogeny of delayed hypersensitivity in young turkeys

Hypersensitivity to phytohemagglutinin (PHA-P) and Freund's adjuvant containing Mycobacterium tuberculosis was investigated in turkey poults. The kinetics, as indicated by dosage and response time after sensitization, were similar to responses in other birds and laboratory mammals. Newly hatched poults demonstrated delayed hypersensitivity responses, and 2 week old poults exhibited responses of greater magnitude than 8 week old poults. The turkey is proposed as another acceptable species for study of cell-mediated immunity (CMI).
On the recovery of adhesiveness by trypsin-dissociated cells

A sensitive method for assaying aggregation of dissociated cells has been developed which allows the determination of the mean number of cells per aggregate of a cell population. We have demonstrated that exposure of dissociated 6- or 7-day chick embryo neural retinal cells to trypsin in calcium-free solution renders them unable to aggregate for a half hour in stirred cell suspensions. Aggregation was noticeable first at 30 to 40 minutes and, progressed to the formation of massive compact aggregates. Because the half-hour aggregation lag occurred both in the absence of serum and in medium reclaimed from aggregated preparations, the possibilities were excluded that it was due either to an inhibitor of aggregation in the serum, or was the time required for release into the medium of soluble aggregation-promoting materials emanating from the cells themselves. Cells dissociated by divalent cation withdrawal (Ca++, Mg++-free saline with EDTA) aggregated without a lag. The trypsin-induced lag does not appear to be the result of trypsin adsorbed to the, surfaces of dissociated cells, as the lag is not abolished by addition of trypsin inhibitors to the aggregation medium. Microelectrophoresis of dissociated cells did not reveal changes in surface charge density during recovery from trypsinization. A variety of proteins and calcium ion, if present during trypsinization, protect the cells against the trypsin-induced aggregation lag. If the temperature was reduced from 37 to 6°C, aggregation of fully adhesive cell populations came to a complete halt within 2 to 3 minutes. Aggregation resumed with a 5 to 10 minute delay when the temperature was returned to 37°C. The rapidity of onset and reversal of inhibition of aggregation by low temperature treatment militates against the hypothesis that the low-temperature inhibition of aggregation acts by suppressing the synthesis of cell surface components necessary for adhesion. The abolition of the aggregation lag in trypsinized cells was also shown to be temperature-dependent; a 20-minute cold, pulse administered in the middle of the lag period extended the length of the lag by exactly 20 minutes.
Low-resistance AuZn gate ohmic contacts for InP JFETs

Abstract The fabrication and characteristics of AuZn gate ohmic contacts for InP JFETs are presented. The contacts are 1 μm × 600 μm in area and less than 3000 A deep to maintain the quality of the pn junction below the surface. The contacts are fabricated by the simultaneous evaporation of Au and Zn and hot-plate alloyed at 410°C. To prevent the outdiffusion of Zn into the subsequently-deposited thick gold layer, a diffusion barrier of TiW is used. The best specific contact resistance was measured to be 3.7 × 10−5 Ω-cm2 for a Be doping of 1018 cm−3 which is among the lowest values ever reported for contacts to p-type InP. This d.c. contact resistance value was found to be in good agreement with microwave measurements performed on JFETs under normal operating conditions. In the InP JFET, the gate contact resistance dominates the other gate resistances and its effect on the microwave performance is discussed.
CONCEPTIONS OF FEMININITY AND MASCULINITY: 1974-1983

Research on the two central aspects of sex roles has indicated contrasting patterns over the past few decades. Attitudes about women's role have changed markedly, becoming consistently less traditional, more for women than for men, and especially regarding extrafamilial dimensions (Mason, et al., 1976; Schreiber, 1978). Throughout the period, sex differences have persisted and may actually be -increasing (McBroom, 1984), with females' attitudes being less traditional than males' attitudes. Perceptions of the "typical personality" traits of women and men show a markedly different pattern. In the first place, there is substantial agreement between the sexes regarding sex-related personality traits, and substantial consistency across researches regarding the content of these perceptions (Williams & Best, 1982; Lueptow, ,1984). Except for the anomaly in the recent research of Eagly and Steffen ( 1984), where women were more agentic, studies have been consistent in delineating the content of masculinity and femininity ratings (Lueptow, 1984). This consistency in findings from the 1950's on, suggests that in contrast to the evidence on attitudes about women's role, perceptions of sex-differentiated personality have been stable and unchanging. However, except for Williams and Best's (1982) incidental report of stability in the masculinity scores of Wake Forest students between 1972 and 1981, and my limited 3-year report on the present project (Lueptow, 1980), there are as yet no valid longitudinal assessments of change or stability in perceptions of personality comparable to the studies of attitudes about women's role. Given the changes in roles and in attitudes about women's role, it would '
Mechanism of Hydrogen Production in [Fe-Fe]-Hydrogenase: A Density Functional Theory Study (Preprint)

Abstract : [Fe-Fe]-hydrogenases are a class of metallo-enzymes that catalyze the production of H2 from two protons and two electrons. In this work, we used density functional theory (DFT) calculations to analyze the mechanism of hydrogen production, providing insight into the role of the intermediates in the catalysis. We also validated the exchange-correlation functional applied within DFT for model compounds of the active site in [Fe-Fe]-hydrogenase, enabling us a reliable application for understanding previously established hydrogen production hypotheses, as well as providing a starting point for a future investigation of the effects of the protein environment on the catalytic mechanism of [Fe-Fe]-hydrogenases.
Order of onset of substance abuse and depression in a sample of depressed outpatients

Drug abuse has been thought to cause depression, or to serve as a form of self-medication for depression. Our objective was to examine whether specific types of drug abuse preceded or followed the onset of depression. A retrospective, blinded case-controlled assessment of the drug and depressive history of depressed outpatients was conducted. Three hundred seventy-five patients with major depressive disorder were evaluated for comorbid drug dependence using the Structured Clinical Interview for DSM-III-R (SCID). They were selected from the psychiatric outpatient department of a metropolitan teaching hospital and grouped into homogeneous classes of drug dependence including alcohol, cannabis, cocaine, amphetamine, LSD, hypnosedative, opiate, and polysubstance use. We determined the percent of depressed patients with each specific type of drug abuse, their age of onset of depression and onset of specific drug abuse, and the mean number of lifetime depressive episodes for each patient. We found that alcohol dependence followed the onset of first life depression by 4.7 years (P = .02, two-tailed). Among polydrug-dependent patients, each drug abused followed the onset of depression, except for LSD, which coincided with the onset of depression. Among polydrug users, cocaine dependence occurred 6.8 years after the first major depressive episode (P = .007) and alcohol dependence 4.5 years after the onset of depression (P = .007). Opiate and sedative users had the least number of lifetime depressive episodes (3.7), and LSD and cocaine users had the greatest number (12.2). We conclude that alcohol and cocaine use in this sample of depressed outpatients conformed to a pattern of self-medication.
Neuronal activity in the brain stem reticular formation during performance of a "go-no go" visual attention task in the monkey.

Abstract We recorded extracellular unit activity in the brain stem and sensorimotor cortex of rhesus monkeys during the performance of a visual discrimination (attention) task. The animals were required to press a transilluminated disk to red stimuli (“go” trials) and withhold pressing to green stimuli (“no go” trials). Correct performance was rewarded with fruit juice. A total of 235 task-related units (170 in and around the mesopontine reticular formation and 65 in the sensorimotor cortex) was studied in four animals. We classified all units as either type I or type II. Type I units showed changes during go trials only; these changes occurred relatively late in the trial, and in relation to some motor aspect of the task. The majority (81%) of the sensorimotor units was type I. Type II units showed changes in relation to both go and no go trials; these changes typically occurred early in the trial, suggesting that these units are related to input or integration processes rather than to motor output. The majority (67%) of the subcortical units in and around the mesopontine reticular formation showed type II activity, suggesting that this system is involved in the central processes underlying attention in visual discrimination tasks.
Parental attitudes toward organ transplantation

We investigated parental attitudes toward organ donation by surveying the parents of 106 children attending a general pediatric, cystic fibrosis, hematology or nephrology clinic using a printed questionnaire. Only 64% of parents knew that cessation of brain function is the definition of death. Most people (73%) obtained information about organ transplantation from the mass media and significantly fewer (37%) from medical personnel (P less than 0.05). Blacks were less likely than whites to express a desire to be living-related and/or cadaveric donors (P less than 0.05).