cssi/SciSciGPT-SciSciNet huggingface dataset:
Clinical factors impact on the presence of transient ischaemic dilatation of the left ventricle on stress myocardial SPECT

Abstract Transient ischaemic dilatation (TID) on myocardial perfusion imaging (MPI) is an indicator of severe coronary artery disease (CAD), but its dependence on other clinical variables is less well defined. The aim of this study was to explore the relationship between clinical variables, particularly left ventricular hypertrophy (LVH), diabetes, and TID. Methods: MPI studies of 103 consecutive patients who underwent coronary angiography within 6 months and transthoracic echocardiography within a year of stress ECG-gated MPI were retrospectively analysed. TID was assessed visually with the consensus agreement of 2 readers. Summed stress scores (SSS) were determined using the standard 17 segment module. Severe CAD was defined as >90% LAD stenosis, or > 2 vessels >90% stenosis. LVH was defined as LV wall thickness >1.1mm on echo. Results: * . Variable TID positive TID negative P value Severe CAD 15/28 (62%) 28/75 (35%) * LVH 10/28 (36%) 9/75 (12%) * Diabetes 11/28 (38%) 12/75 (16%) Female 11/28 (38%) 18/75 (24%) * Independent predictors of TID by logistic regression. The specificity of TID for severe CAD (81% overall) fell from 87% without LVH, to 54% with LVH. The specificity of TID for CAD fell from 84% without diabetes to 60% with diabetes. Conclusion: The specificity of TID for severe CAD is compromised in the presence of LVH and diabetes.
The crosslinking of epoxy resins at interfaces. II. At an aromatic polyamide surface

The first 200–400 nm of crosslinked epoxy resin adjacent to an aromatic polyamide (aramid) surface were characterized by internal reflection spectroscopy (IRS) using an aramid-coated IRS element. The crosslinking kinetics and final crosslinked state of an anhydride-cured epoxy resin were strongly affected by the aramid surface, which produced a localized increase in the rate of anhydride consumption and a decrease in the yield of ester products. An aromatic amine-cured epoxy resin was less affected by the aramid surface. Unidirectional aramid fiber:epoxy composites were examined by dynamic mechanical analysis (DMA), and differential scanning calorimetry (DSC). The chemical changes detected spectroscopically were shown to correlate with mechanical and thermal transition data obtained by DMA and DSC. These results are rationalized on the basis of the effect of absorbed moisture in the aramid on the crosslinking chemistry.
CHEMICALLY INDUCED ECDYSIS AND ISOLATION OF NUCLEI FROM THE DINOFLAGELLATES GONYAULAX POLYEDRA AND GONYAULAX TAMERENSIS

Armored dinoflagellates such as Gonyaulax sp. are not good candidates for isolation of intact clean nuclei, due to difficulty in breaking the cells. Previously, isolation of nuclei from Gonyaulax was achieved using vigorous cell disruption by ultrasonication (Rizzo & Hastings, unpublished observations). A detergent method for production of spheroplasts from Gonyaulax was published some time ago (Adamich & Sweeney, 1976), but was not reproducible (Rizzo & Hastings, Morris & Rizzo, unpublished observations). We describe here a modification of the method described by Adamich & Sweeney that is highly reproducible. Ecdysis and production of intact dinoflagellate spheroplasts with a yield of virtually 100% within 5 minutes, has been achieved through the use of anionic and nonionic detergents in hypotonic buffers. This method of ecdysis followed by a gentle spheroplast breakage in a hypotonic buffer allowed the release of nuclei for later biochemical analysis with minimal damage or breakage. The nuclei are subsequently purified by centrifugation in a Ficoll discontinuous gradient.
The Art of Lionel Trains: Toy Trains and the American Dream

The Art of Lionel Trains: Toy Trains and the American Dream Roger Carp. Waukesha, WI: Kalmback Publishing, 2004. One Christmas, when my son was just a few years old, my father presented his first grandchild with an elaborate Lionel train set. It was only after reading Roger Carp's The Art of Lionel Trains: Toy Trains and the American Dream that I truly understood the meaning and significance of this gift. Carp, a member of the editorial staff of Classic Toy Trains magazine since 1988 and the author of two other books on Lionel trains, chronicles the history of Lionel toy trains through an analysis of the images in its catalogs and advertisements. He shows how the artwork inspired by Lionel reflects American attitudes and values, especially related to childhood, gender, family, success, and technology. Founded by Joshua Cohen (later Cowen) as an "electrical novelties" company in New York in the early 190Os, Lionel went on to become one of the most recognizable brands in America. Early on, Cohen set out to dominate the American toy train market, and knew that the best way to do this was to capture the public's attention through attractive annual catalogs and color advertisements in Sunday newspapers. Although this era was the "golden age of illustration," artists' names were not mentioned. Instead, Lionel adopted an overall graphic style characterized by elegance and sophistication that captured the attention of American consumers interested in top-of-the-line, high-quality products for their families. Through a highly developed marketing plan, Lionel convinced the American public that youths needed trains, which were, in fact, the keys to happy and productive childhoods, at least for boys. Illustrations showed that by operating trains, boys, often wearing white shirts and ties or full suits, were learning how to build character and become successful men. Train play also enhanced male bonding across generations as fathers, sons, and sometimes grandfathers learned together about engineering, electronics, and transportation. As Carp asserts, "The implication was clear: Lionel trains were for boys, especially mature ones able to appreciate their beauty and merit" (43). Mothers and girls in Lionel advertisements, if they were depicted at all, stood off to the side, looking on passively as active males enjoyed all the fun. If Lionel advertisements reinforced traditional gender roles and cultural values, they also established an important holiday ritual: the train circling the Christmas tree. …
Contrast-induced nephropathy: current practices among cardiologists.

Objective: Contrast-induced nephropathy (CIN) is a serious complication of diagnostic and therapeutic coronary angiography. There are an increasing number of guidelines in the literature to help lessen this complication. Practice patterns in the cardiology community remain relatively unknown. This survey is an effort to better understand such practices. Methods: Questions were written based on the American College of Cardiology (ACC), the American Heart Association (AHA), and the Society of Cardiovascular Angiography and Intervention (SCAI) guidelines to identify cardiologist background and experience. The survey was emailed to 5000 randomly chosen cardiologists in December 2009. Results: A total of 291 responses were received. Among these, 97% reported checking renal function in all patients prior to angiography, 45% checked both estimated glomerular filtration rate (eGFR) and serum creatinine (SCr), 31% checked SCr alone, 19% checked eGFR alone, and 2% checked albumin-to-creatinine (A–C) ratio. Among re...
Metastasis induced by overexpression of p185neu‐T after orthotopic injection into a prostatic epithelial cell line (NbE)

Overexpression of p185erbB2/neu has been detected in many adenocarcinomas, including prostatic cancer. In this study, a nontumorigenic cell line isolated from the rat prostatic epithelium (NbE) transfected with the activated oncogene p185neu-T was used to investigate the role of this oncogene in tumor progression. When clones overexpressing p185neu-T were injected orthotopically (1.5 to 2 × 106 cells) into the dorsal-lateral prostates of nude mice, prostatic tumors were detected in all mice injected and metastasis to the skeletal muscle in the rib area in 60–80% of the mice injected. Tumor and metastasis origin was confirmed by reselection with G418 and reverse transcriptase–polymerase chain reaction. Control cell lines produced no prostatic tumors or metastases. Incubation at low density (12 500 cells/2 cm2) in serum-free medium revealed that clones overexpressing p185neu-T had a higher rate of [3H]thymidine incorporation than did control clones on 3, 5, and 7 d after plating (P ≤ 0.0001) and constitutively overexpressed the 2.6-kb ornithine decarboxylase transcript. Additionally, clones overexpressing p185neu-T demonstrated an increased expression of epidermal growth factor receptor and p180erbB4, as judged by RNA blot analysis. Together these data support the hypothesis that overexpression of p185neu-T fosters tumor progression by several pathways, including induction of the metastatic cascade, increased proliferative capabilities, and increased expression of other members of the erbB2 gene family. Mol. Carcinog. 19:165–175, 1997. © 1997 Wiley-Liss, Inc.
Taking the Keys from Grandpa

Elderly drivers, which are one of the fastest growing segments of the driving population, have a high accident and fatality rate. Because of this growth and the probability that traffic accidents are linked to medical conditions that are more prevalent among the elderly, there has been renewed interest in state policies and administrative practices for awarding and renewing drivers' licenses. This article discusses variations that are observed across states in law and administrative practice. A longitudinal analysis of data on crashes involving elderly drivers in fifteen states indicates that crash rates are directly related to the length of the renewal cycle for older drivers and inversely related to the stringency of testing at renewal. It is also likely that states requiring physicians to report conditions that would impair driving will experience lower crash rates. Due to inaccuracies in the data, results from a secondary analysis of policy impacts on licensing rates were inconclusive.
Influence of craniofacial morphology on hyoid movement: a preliminary correlational study.

There has been little attention given to the relationship between variations in normal craniofacial morphology and swallowing physiology. This preliminary investigation evaluated the relationship between the Frankfort-mandibular plane angle (FMA) and hyoid displacement during swallowing. Hyoid movement was evaluated during 12-ml and 24-ml swallows of liquid barium in 12 healthy subjects (age = 20–29 years, median = 23 years). Lateral projection videofluorography was utilized. Positions of the hyoid at maximum forward displacement, maximum upward displacement, starting position, and ending position were determined using image analysis software. The mean FMA was 28.92° ± 4.08° (mean ± SD, range = 20°–34°). A Pearson correlation (≤0.05) demonstrated that hyoid forward displacement was significantly inversely correlated with the FMA [R = −0.68, p = 0.015 (12 ml) and R = −0.72, p = 0.009 (24 ml)]; thus, the greater the FMA, the smaller the hyoid forward displacement. Upward displacement of the hyoid was not significantly correlated with FMA for 12-ml (R = −0.41, p = 0.55) or 24-ml swallows (R = 0.21, p = 0.512). In addition, there was no significant correlation between hyoid starting or ending positions. In conclusion, the results of this preliminary study suggest that normal variations in morphology, as measured by the FMA, may influence hyoid movement and therefore affect swallowing physiology.
The Influence of Diabetes, Hypertension, and Stroke on Ethnic Differences in Physical and Cognitive Functioning in an Ethnically Diverse Older Population

Abstract Prevention of decline in cognitive and physical functioning in the elderly has become an important focus in geriatric medicine. Hispanics are among the fastest-growing group of elderly in the United States, yet few data are available on functional impairments in this group. We examined the association between ethnicity (non-Hispanic whites [NHW], English-speaking Hispanics [EH], and Spanish-speaking Hispanics [SH]) and cognitive status, self-assessed functional status, and physical performance in a community-dwelling sample of 589 people aged ⩾ 60 years. The purpose of this study was to examine the association between ethnicity and these measures of functional status and to evaluate the influence of comorbid stroke, diabetes, and hypertension on this association. We found that EH and SH had significantly lower scores on the MiniMental State Exam than NHW, but that this difference was almost entirely due to educational level. When SH whose educational attainment was grade 8 or higher were compared to NHWs, there were no differences in cognitive functioning. Those with diabetes and stroke had poorer cognitive functioning. Among those with stroke, EH and SH women had more self-assessed functional limitations (IADLs and ADLs) than NHW. Male SH and EH with diabetes also had more self-assessed functional limitations than NHW. SH with two or three of these conditions had more IADL limitations. Our results suggest that elderly communitydwelling Hispanics experience greater levels of disability and that this is due, in part, to lower socioeconomic status and higher prevalence of disabling conditions.
Food Versus Fuel: Extractive Industries, Insecure Land Tenure, and Gaps in World Food Production

Summary Corporations now go “to the ends of the earth” to extract natural resources like oil and diamonds from the earth at the same time that farmers, investors, and development experts try to expand the supply of food, sometimes through large land acquisitions in remote regions. These two processes of globalization interact in important ways. Cross-national analyses indicate that oil and mineral dependent nations with neo-patrimonial elites have lower than expected areas under cultivation and yields from cereal crops. Booms in extractive sectors and neo-patrimonial practices in governance have debilitated agricultural enterprises within nations and conceivably throughout the globe.
The application of cognitive simulation techniques to work measurement and methods analysis of production control tasks

Abstract The implementation of flexible control in production and manufacturing operations has resulted in jobs largely consisting of cognitive tasks in which performance is determined by worker goals, knowledge, and transient task-related conditions. As has been the case for traditional jobs that are characterized by predictable and/or repetitive operations, jobs that emphasize cognitive tasks also require examination. This paper presents cognitive simulation as a promising tool for work measurement and methods analysis of the cognitive tasks found within such jobs. Levels of performance, taxonomies of tasks, and the sequencing of elemental tasks are discussed from this perspective. It is noted that existing techniques for developing cognitive simulations have important similarities to the knowledge acquisition methods used to develop expert systems. Several representative techniques and their application are then discussed in terms of their potential value to work measurement and methods analysis.
Epidemiology and pathology of intraventricular tumors

Tumors that primarily or exclusively involve the ventricular system constitute a rare and heterogeneous group. Certain histologic tumor types predominantly occur in children, whereas others are more common in adults. Tumor location provides additional clues to correct diagnosis. When used in conjunction with clinical and radiologic data, histopathologic features can distinguish among this wide range of possibilities to provide the correct diagnosis for optimal patient management.
Specific binding of antitumour drug cis -Pt(NH 3 ) 2 Cl 2 to DNA rich in guanine and cytosine

ONE of the more effective cis-platinum antitumour compounds currently being tested in cancer chemotherapy is cis-Pt(NH3)2Cl2 (ref. 1). Evidence suggests that DNA is the effective site of action of the platinum drug2,3. This study was initiated to determine the effective binding site on DNA. Roberts and Pascoe have noted the similarity of action between cis-Pt (NH3)2Cl2 and the classical antitumour bifunctional alkylating agents which crosslink DNA (ref. 2). Low concentrations of several cis-platinum compounds suppress DNA synthesis in vitro while affecting protein and RNA synthesis to a much lesser extent3. The studies by Horacek and Drobnik employing ultraviolet absorption spectroscopy indicate that the platinum moiety binds to the bases of DNA rather than to the phosphate backbone4. Spectroscopic studies suggest that cis-Pt(NH3)2Cl2 preferentially binds to guanine–cytosine (G–C)-rich DNA5,6. An increase in the buoyant density of T7 DNA and calf thymus DNA has been reported when one of several platinum compounds is present in solution5,7. Here we report that the binding of cis-Pt(NH3)2Cl2 to DNA results in large increases in buoyant density which are proportional to the G–C content of the DNA and to the molar ratio of platinum to DNA-P.
Wavelength modulation of semiconductor lasers for absorption spectroscopy employing harmonic detection

Wavelength modulation spectroscopy using semiconductor lasers is a sensitive tool for identifying species and measuring concentrations, velocities, and temperature in gaseous media. One advantage of modulation spectroscopy is that detection is carried out at frequencies far from the base-band noise, improving the signal-to-noise ratio. An additional benefit of performing wavelength modulation spectroscopy is that it allows for detection at harmonics of the modulation frequency. When a sinusoidal modulation is imposed, the harmonic detection signals resemble the frequency derivatives of the absorption profile, where the derivative order corresponds to the harmonic detection order. For this reason, the higher harmonic signals can be exploited to obtain more sensitive measurements of spectroscopic parameters, such as lineshape profile, absorption cross-section, temperature, and concentration. Wavelength modulation of semiconductor lasers, such as Fabry-Perot, vertical cavity, and external-cavity lasers, is discussed along with the advantages and disadvantages associated with each laser source. Applications of wavelength modulation spectroscopy are explored and it is shown that the higher harmonic detection signals exhibit structure and magnitude variations that are extremely useful in many spectroscopic applications.
Endothelin-A Receptor Blockade in Porcine Pulmonary Hypertension

Endothelin-1 can cause pulmonary vasoconstriction via endothelin-A (ETA) receptor activation. We hypothesized that ETA blockers (EMD 122946 and BQ 610) would reduce hypoxia-induced (HYP) but not group B streptococcal infusion (GBS)-induced pulmonary hypertension in a juvenile whole animal model. Pulmonary hypertension was created by exposing chronically instrumented piglets to HYP (n = 12) or heat-killed GBS (n = 11). ETA blockade was produced by increasing bolus doses of EMD122946 or BQ 610. Pulmonary arterial pressure (PAP), systemic arterial pressure (SAP), left atrial pressure, central venous pressure, and cardiac output were continuously measured. Pulmonary and systemic vascular resistance indices (PVRI and SVRI) were calculated. HYP doubled PAP and PVRI. Both ETA blockers decreased PAP and PVRI in a dose-dependent manner in HYP, with high doses decreasing PVRI to baseline and reducing PAP by 50%. GBS also doubled both PAP and PVRI. EMD 122946 did not change PAP or PVRI in GBS, although BQ 610 markedly increased PVRI (>100% increase with 0.15 mg/kg) and showed a trend toward increasing PAP. Both models showed minimal (<25%) changes in SAP or SVRI. Neither ETA blocker changed baseline hemodynamics in the absence of HYP or GBS. Pao2 did not change with GBS but decreased with BQ 610. ETA receptor blockade attenuated hypoxic, but not GBS induced pulmonary hypertension. BQ 610 worsened PVRI and oxygenation in the GBS model. Differences in response to ETA blockade in pulmonary hypertension may be seen depending on the etiology (hypoxia versus infection-associated), and the specific ETA antagonist used.
Do thallium myocardial perfusion scan abnormalities predict survival in sarcoid patients without cardiac symptoms

Whereas the total mortality rate for sarcoidosis is 0.2 per 100,000, the prognosis, when the heart is involved, is very much worse. The authors used the difference in mortality rate to infer whether thallium 201 myocardial perfusion scan abnormalities correspond to myocardial sarcoid by making the simplifying assumption that if they do, then patients with abnormal scans will be found to have a death rate similar to patients with sarcoid heart disease. The authors therefore analyzed complete survival data on 52 sarcoid patients without cardiac symptoms an average of eighty-nine months after they had been scanned as part of a protocol. By use of survival analysis (the Cox proportional hazards model), the only variable that was significantly associated with survival was age. The patients' scan pattern, treatment status, gender, and race were not significantly related to survival. The authors conclude that thallium myocardial perfusion scans cannot reliably be used to diagnose sarcoid heart disease in sarcoid patients without cardiac symptoms.
Gender differences and factors associated with the receipt of thrombolytic therapy in patients with acute myocardial infarction: A community-wide perspective

Abstract In spite of national interest in gender differences in the presentation and management of chronic disease, limited information is available about possible gender differences in the receipt of thrombolytic therapy after acute myocardial infarction (AMI). As part of an ongoing community-based study of AMI, we examined gender differences in the receipt of thrombolytic therapy among 2885 patients with confirmed AMI. The study sample consisted of 1680 males and 1205 females with validated AMI who were admitted to 16 hospitals in the Worcester, Massachusetts, metropolitan area in four study periods between 1986 and 1991. During the years under study, 24.4% of men and 14.4% of women received thrombolytic therapy. Increases over time in the use of thrombolytic therapy were seen in both men (13.9% in 1986; 31.6% in 1991) and women (3.2% in 1986; 19.0% in 1991). After controlling for a variety of factors that might affect use of thrombolytic agents, younger age, absence of a history of either congestive heart failure or stroke, and experiencing a Q-wave AMI were associated with receipt of thrombolytic therapy in both men and women; having an anterior AMI also was associated with use of thrombolytic agents in men. Women without as compared with those with a history of angina pectoris were significantly more likely to receive thrombolytics. Men who had Medicare insurance were significantly less likely to receive thrombolytics than were men with other types of health insurance. When this analysis was restricted to patients who were seen in area-wide hospitals within 6 hours of the onset of symptoms suggestive of AMI, similar factors were associated with the receipt of thrombolytic agents in men and women. The results of this community-wide study suggest a marked increase over the 5-year study period in the use of thrombolytic therapy in both men and women, with a greater relative increase observed in women. A relatively similar profile of patients likely to receive thrombolytic therapy was seen in both men and women.
PRODUCTIVE TIME OF HOUSEHOLD HEADS

This study is an analysis of the utility value of time. Time is viewed on a productivity continuum with activities that result in measurable products such as income or home sewing at one extreme of the continuum and activities such as sleep at the other extreme. The use of time by unemployed and employed heads of households was the basis for this analysis. Four measures of time were constructed to determine the amount of time spent in market, household, leisure and personal activities. Unemployed heads of households spent more time in household and leisure activities than employed heads. Assuming that household activities have productive value, time spent in child care, shopping, house cleaning, etc., were viewed as having utility value for the household. Thus, reallocated time had utility value for the household. In addition, it was found that a significant relationship existed between employment status and use of time, regardless of position on the productivity continuum. From this study comes a better understanding of how time is reallocated during unemployment so that the economic loss for the household as well as the economy can be minimized.
WE-G-217BCD-08: Image Quality Effects of Dynamic Iodine Concentrations for Contrast-Enhanced Cone-Beam CT.

Purpose: To study the imageeffects of the time‐wise dynamic aspect of intravenous contrast agents to enable contrast‐enhanced cone‐beam CT (CE‐ CBCT) localization of liver lesions for stereotactic body radiation therapy(SBRT).Methods: A model was developed to study dynamic IV contrast agents using static phantoms and to derive optimum parameters for CE‐ CBCTimaging. Ten samples containing iodine at 0–5 mg/mL were prepared in cylindrical tubes, corresponding roughly to 0–100 HU as measured by 120 kV helical CTimaging. Each sample was imaged separately in a tissue‐ equivalent phantom, yielding ten datasets (roughly 650 projections each) corresponding to these static CBCTimages. To reconstructimages of dynamic contrast concentrations, the CBCT 2D projections were re‐ assembled to match the expected amount of contrast at different points in time. This model was applied to published hepatic contrast enhancement curves, and optimum imaging and contrast injection parameters were derived. Results: A signal‐to‐noise ratio (SNR) decrease of 25%–75% in dynamic CE‐CBCT images from ideal CT of samples with a 20–100 HU difference from water was observed in the un‐optimized scans. This demonstrates the difficulty of CE‐CBCT, and was noticed even in geometries that minimize or eliminate x‐ray scatter, detector glare, and motion. Using our model, we found parameters for iodine injection, CBCT scanning, and injection/scanning timing which optimize contrast enhancement, and a 100% SNR increase with respect to the un‐optimized scans was achieved. Conclusions: The effect of IV contrast is severely degraded in CBCT, and optimization of image and timing parameters is crucial for improved CE‐CBCT imaging for target localization. CBCT has very low temporal resolution, and the pharmacokinetics of IV contrast must be carefully considered in order to apply this technique to localize liver lesions for SBRT. This model will be used to establish the feasibility of CE‐ CBCT for routine localization of liver lesions.
Ground state proton capture reactions from 20 to 100 MeV.

Proton capture reactions on targets of $^{11}\mathrm{B}$, $^{12}\mathrm{C}$, $^{15}\mathrm{N}$, $^{16}\mathrm{O}$, and $^{27}\mathrm{Al}$ were measured from ${E}_{\mathrm{p}=20}$ to 100 MeV. The energy dependence of the ${\ensuremath{\theta}}_{\ensuremath{\gamma}}$=60\ifmmode^\circ\else\textdegree\fi{} differential cross sections are presented for captures populating the ground states of $^{12}\mathrm{C}$, $^{13}\mathrm{N}$, $^{16}\mathrm{O}$, $^{17}\mathrm{F}$, and $^{28}\mathrm{Si}$. Differential-cross-section and analyzing-power angular distributions are presented at bombarding energies of ${E}_{\mathrm{p}=20.8}$, 28.35, 49.2, and 49.69 MeV. Calculations from two capture-reaction models are compared to the data.
Extraction of net interfacial polarization charge from Al0.54In0.12Ga0.34N/GaN high electron mobility transistors grown by metalorganic chemical vapor deposition

AlxInyGa(1-x-y)N materials show promise for use in GaN-based heterojunction devices. The growth of these materials has developed to the point where they are beginning to see implementation in high electron mobility transistors (HEMTs) and light emitting diodes. However, the electrical properties of these materials are still poorly understood, especially as related to the net polarization charge at the AlInGaN/GaN interface (Qπ(net)). All theoretical calculations of Qπ(net) share the same weakness: dependence upon polarization bowing parameters, which describe the deviation in Qπ(net) from Vegard's law. In this study, direct analysis of Qπ(net) for Al0.54In0.12Ga0.34N/GaN HEMTs is reported as extracted from C-V, I-V, and Hall measurements performed on samples grown by metalorganic chemical vapor deposition. An average value for Qπ(net) is calculated to be 2.015 × 10−6 C/cm2, with just 6.5% variation between measurement techniques.
High-temperature Debye-Huckel correlated solubilities of calcium sulfate in aqueous sodium perchlorate solutions

The solubilities of CaSO4·2H2O at 298 K and of CaSO4 at 423 and 523 K have been determined in aqueous solutions of sodium perchlorate having molalities from 0 to 6 mol kg−1 of NaClO4. When the results were treated with an extended Debye-Huckel equation, substantial agreement with theory was observed to moderate ionic strengths at all three temperatures. The results therefore support previous observations of aqueous electrolyte behavior adhering to a Debye-Huckel treatment to high temperatures. However, at high ionic strengths (1 to 6 mol kg−1) of supporting salt the solubilities of CaSO4·2H2O and of CaSO4 were sharply lower than the corresponding solubilities in aqueous sodium chloride, sodium nitrate, and lithium nitrate solutions. Several attempts to explain these differences in solubility are presented. In addition, the activity coefficient behavior of calcium sulfate in the aqueous sodium perchlorate solutions is given.
Quantum gravity, random geometry and critical phenomena

We discuss the theory of non-critical strings with extrinsic curvature embedded in a target space dimensiond greater than one. We emphasize the analogy between 2d gravity coupled to matter and non self-avoiding liquid-like membranes with bending rigidity. We first outline the exact solution for strings in dimensionsd 1. Evidence from recent and ongoing numerical simulations of dynamically triangulated random surfaces indicate that there is a non-trivial crossover from a crumpled to an extended surface as the bending rigidity is increased. If the cross-over is a true second order phase transition corresponding to a critical point there is the exciting possibility of obtaining a well defined continuum string theory ford>1.
Effects of testosterone therapy on muscle performance and physical function in older men with mobility limitations (The TOM Trial): Design and methods

The TOM study is the first, single-site, placebo-controlled, randomized clinical trial designed to comprehensively determine the effects of testosterone administration on muscle strength and physical function in older men with mobility limitations. A total of 252 community dwelling individuals aged 65 and older with low testosterone levels and self-reported limitations in mobility and short physical performance battery (SPPB) scores between 4 and 9 will be randomized to receive either placebo or testosterone therapy for 6 months. The primary objective is to determine whether testosterone therapy improves maximal voluntary muscle strength as quantified by the one repetition maximum. Secondary outcomes will include measures of physical function (walking, stair climbing and a lifting and lowering task), habitual physical activity and self-reported disability. The effects of testosterone on affect, fatigue and sense of well being will also be assessed. Unique aspects of the TOM Trial include selection of men with self-reported as well as objectively demonstrable functional limitations, community-based screening and recruitment, adjustment of testosterone dose to ensure serum testosterone levels in the target range while maintaining blinding, and inclusion of a range of self-reported and performance-based physical function measures as outcomes. Clinicaltrials.gov identifier: NCT00240981.
Inhibition of bovine plasma amine oxidase by 1,4-diamino-2-butenes and -2-butynes

Abstract Bovine plasma amine oxidase (BPAO) was previously shown to be irreversibly inhibited by propargylamine and 2-chloroallylamine. 1,4-Diamine versions of these two compounds are here shown to be highly potent inactivators, with IC 50 values near 20 μM. Mono- N -alkylation or N , N -dialkylation greatly lowered the inactivation potency in every case, whereas the mono- N -acyl derivatives were also weaker inhibitors and enzyme activity was recoverable. The finding that the bis-primary amines 1,4-diamino-2-butyne (a known potent inhibitor of diamine oxidases) and Z -2-chloro-1,4-diamino-2-butene are potent inactivators of BPAO is suggestive of unexpected similarities between plasma amine oxidase and the diamine oxidases and implies that it may be unwise to attempt to develop selective inhibitors of diamine oxidase using a diamine construct.
Temporal changes in drug metabolism (CYP1A2, CYP2D6 and CYP3A Activity) during pregnancy

Objective The purpose of this study was to determine whether drug metabolism (CYP1A2, CYP2D6 and CYP3A) activity varies in the pregnant state compared with the nonpregnant state. Study design Subjects were studied at 14 to18 weeks of gestation, 24 to 28 weeks of gestation, and 36 to 40 weeks of gestation and again at 6 to 8 weeks after the delivery. Twenty-five subjects completed all 4 study periods and had evaluable data. Salivary caffeine clearance was used as a measure of CYP1A2 activity; dextromethorphan O- and N-demethylation were used to assess CYP2D6 and CYP3A activity, respectively. Results CYP1A2 activity was significantly reduced at all periods of the pregnancy as compared with the postpartum period during the first (−32.8% ± 22.8%), second (−48.1% ± 27%), and third periods (−65.2% ± 15.3%), respectively. In contrast, CYP2D6 activity was increased significantly throughout the pregnancy (25.6% ± 58.3% at 14-18 weeks of gestation, 34.8% ± 41.4% at 24-28 weeks of gestation, and 47.8% ± 24.7% at 36-40 weeks of gestation) as compared with the postpartum period. CYP3A activity was consistently, significantly increased (35%-38%) during all stages of the pregnancy. Conclusion Opposing changes in drug metabolism occur during pregnancy, with CYP1A2 activity decreased and CYP2D6 and CYP3A activities increased. The direction of dosing adjustments during pregnancy will depend on the drug and the enzyme that is responsible for its metabolism.
Compressive sensing with sub-Nyquist clocks using frequency division multiplexed random sequences

Compressive sensing is a newly emerging theory that provides the means to recover a signal from samples obtained at a sub-Nyquist rate. This in turn leads to tremendous reduction in power consumption of receivers because of the direct correlations between the sampling rate and power consumption of analog-to-digital converters, which constitutes a considerable amount of the receiver's power consumption. In this paper, we propose an architecture for the random demodulator, which is a compressive sensing based receiver, that requires a sub-Nyquist digital clock rather than a Nyquist rate clock. In a conventional random demodulator, the input signal is mixed with a pseudo random sequence, running at the signal's Nyquist rate and then integrated and sampled. In order to overcome this constraint, we propose the use of frequency division multiplexing, in the analog domain, of many digitally generated random sequences running at a sub-Nyquist rate to generate an effective random sequence. The major gain in this approach is that the restricting requirement of having a fast clock is levitated, thus allowing to extend the capabilities of the random demodulator beyond the restrictions imposed by the digital technology.
Epidemiological and Genetic Correlates of Incident Chlamydia trachomatis Infection in North American Adolescents

Epidemiological and genetic correlated of Chlamydia trachomatis infection were examined prospectively in 124 male and 361 female adolescents at high risk for human immunodeficiency virus type 1 (HIV-1) infection. Seventy percent of subjects were African American and 68% had HIV-1 infection. As expected younger age ( /=2) and prior chlamydial infection predicted chlamydial infection during a 6-56-month follow- up period (P = .02 P = .02 and P =.03 respectively). Human leukocyte antigen (HLA) class II variant DQB1*06 (mostly *0602 and *0603) was associated with chlamydial infection (49% vs. 34%; adjusted relative odds [RO] 1.8; P = .005) as was HLA class I haplotype B*44-Cw*04 (10% vs. 4%; RO 3.2; P = .009). DQB1*06 was found in 9 (75%) of 12 female adolescents with chlamydial pelvic inflammatory disease. In contrast sex ethnicity and HIV-1 infection did not predict chlamydial infection. These findings suggest that antigen presentation in adaptive immune responses may serve as a major factor in effective control of C. trachomatis infection. The underlying mechanisms remain to be experimentally elucidated. (authors)
Casein Kinase II Regulates N-Methyl-d-Aspartate Receptor Activity in Spinal Cords and Pain Hypersensitivity Induced by Nerve Injury

Increased N-methyl-d-aspartate receptor (NMDAR) activity and phosphorylation in the spinal cord are critically involved in the synaptic plasticity and central sensitization associated with neuropathic pain. However, the mechanisms underlying increased NMDAR activity in neuropathic pain conditions remain poorly understood. Here we show that peripheral nerve injury induces a large GluN2A-mediated increase in NMDAR activity in spinal lamina II, but not lamina I, neurons. However, NMDAR currents in spinal dorsal horn neurons are not significantly altered in rat models of diabetic neuropathic pain and resiniferatoxin-induced painful neuropathy (postherpedic neuralgia). Inhibition of protein tyrosine kinases or protein kinase C has little effect on NMDAR currents potentiated by nerve injury. Strikingly, casein kinase II (CK2) inhibitors normalize increased NMDAR currents of dorsal horn neurons in nerve-injured rats. In addition, inhibition of calcineurin, but not protein phosphatase 1/2A, augments NMDAR currents only in control rats. CK2 inhibition blocks the increase in spinal NMDAR activity by the calcineurin inhibitor in control rats. Furthermore, nerve injury significantly increases CK2α and CK2β protein levels in the spinal cord. In addition, inhibition of CK2 or CK2β knockdown at the spinal level substantially reverses pain hypersensitivity induced by nerve injury. Our study indicates that neuropathic pain conditions with different etiologies do not share the same mechanisms, and increased spinal NMDAR activity is distinctly associated with traumatic nerve injury. CK2 plays a prominent role in the potentiation of NMDAR activity in the spinal dorsal horn and may represent a new target for treatments of chronic pain caused by nerve injury.
Ribosomes seen through a glass less darkly

Electron microscopists have made important progress recently in their quest to determine the structure of the ribosome. New insights into the mechanism of protein synthesis are beginning to emerge, and substantial progress is likely in the immediate future.
Pattern descriptors and the unidentified reading frame 6 human mtDNA dinucleotide-binding site

In an effort to identify the structural elements essential to a given protein function a new pattern-directed inference system has been developed. It has been employed to identify a potential dinucleotide-binding domain within the human mitochondrial unidentified reading frame 6 product, thereby supporting an earlier study that this gene may encode a NADH dehydrogenase subunit.
The Ups and Downs of Mutation Frequencies during Aging Can Account for the Apert Syndrome Paternal Age Effect

Apert syndrome is almost always caused by a spontaneous mutation of paternal origin in one of two nucleotides in the fibroblast growth factor receptor 2 gene (FGFR2). The incidence of this disease increases with the age of the father (paternal age effect), and this increase is greater than what would be expected based on the greater number of germ-line divisions in older men. We use a highly sensitive PCR assay to measure the frequencies of the two causal mutations in the sperm of over 300 normal donors with a wide range of ages. The mutation frequencies increase with the age of the sperm donors, and this increase is consistent with the increase in the incidence rate. In both the sperm data and the birth data, the increase is non-monotonic. Further, after normalizing for age, the two Apert syndrome mutation frequencies are correlated within individual sperm donors. We consider a mathematical model for germ-line mutation which reproduces many of the attributes of the data. This model, with other evidence, suggests that part of the increase in both the sperm data and the birth data is due to selection for mutated premeiotic cells. It is likely that a number of other genetic diseases have similar features.
SEM studies on vessels in ferns. 11. Ophioglossum

With scanning electron microscopy (SEM), the nature of metaxylem vessel elements and tracheids was examined inOphioglossum crotalophoroides,O. pendulumsubsp.falcatum, andO. vulgatumroots and rhizomes. Vessels were identified in all species. End walls of vessel elements, which bear perforations, are like lateral wall pitting of those elements in the secondary wall framework and differ only in absence of pit membranes or presence of pit membrane remnants. Some of the perforations contain pit membrane remnants that have large pores, small porosities, or are threadlike or weblike in structure. Dimorphic perforations were found in some vessel elements of rhizomes ofO. pendulumsubsp.falcatum. Tracheids are very likely present in addition to vessels in all three species. The secondary wall framework of both tracheids and vessels is basically scalariform, although deviations in pattern are present. Vessel elements ofOphiglossumare entirely comparable to those of leptosporangiate ferns.
Present and Future Naval Applications for Pulsed Power

Like many industrial organizations, the US Navy is moving away from an era of hydraulic, pneumatic and mechanical devices to an era dominated by electromechanical devices and all-electric controls. The Navy is also moving to replace many traditional weapon systems (all of which are chemical and thermodynamic in nature) with directed energy and electric weapons. For these applications there are few, if any, analogies to industrial applications. Some of the electromechanical devices, such as the electromagnetic aircraft launch system (EMALS) and all the electric weapons under development, such as the electromagnetic (EM) railgun and the high-energy laser, require some form of pulsed power and/or pulse forming network. The stored energy necessary to operate these devices may range from tens of kilojoules to several gigajoules, and their instantaneous power may exceed 20 gigawatts. This paper will discuss the options available to provide these energy and power levels and will discuss the research and engineering challenges that need to be overcome for successful operation and fielding.
Equipment fault detection using spatial signatures

This paper describes a new methodology for equipment fault detection. The key features of this methodology are that it allows for the incorporation of spatial information and that it can be used to detect and diagnose equipment faults simultaneously. This methodology consists of constructing a virtual wafer surface from spatial data and using physically based spatial signature metrics to compare the virtual wafer surface to an established baseline process surface in order to detect equipment faults. Statistical distributional studies of the spatial signature metrics provide the justification of determining the significance of the spatial signature. Data collected from a rapid thermal chemical vapor deposition (RTCVD) process and from a plasma enhanced chemical vapor deposition (PECVD) process are used to illustrate the procedures. This method detected equipment faults for all 11 wafers that were subjected to induced equipment faults in the RTCVD process, and even diagnosed the type of equipment fault for 10 of these wafers. This method also detected 42 of 44 induced equipment faults in the PECVD process.
Decision-Making Theories and Career Assessment: A Psychometric Evaluation of the Decision Making Inventory

To address criticisms that the empirical literature on assessment of career decision making has tended to lack a theoretical base, the present study explored the relevance of a general theory of decision making to career decision making by assessing the psychometric properties of the Decision Making Inventory (DMI), designed to measure Johnson’s decision-making styles, and by exploring the usefulness of the DMI as a predictor of career maturity. The DMI, Form B1 of the Attitudes Scale of the Career Maturity Inventory (CMI), and the Self-Construal Scale were administered to European American college students.The DMI demonstrated adequate reliability, the expected factor structure, and good convergent validity. Relationships with certain subscales of the CMI suggest the DMI has useful predictive validity. Similarities and differences between genders in the relationships between the DMI and CMI were found.
Automatic U(1) Symmetry and Invisible Axion Models Without Domain Walls

The concept of automatic symmetry in grand unified theories is explored further in connection with invisible axions, but without suffering from the difficulty of domain walls. We give a procedure to narrow down the Higgs sector by making use of the concept of N-ality in order to accommodate automatic and color-anomalous U(1) symmetries. Furthermore, the condition of no domain walls eliminates many models leaving only a few acceptable. For example, we find that in both SU(7) and SU(9) only one model survives our criteria. The latter one supports the model of Dimopoulos et al., which was based on a specific choice of Higgs scalars.
Optical Anisotropy in Individual Porous Silicon Nanoparticles Containing Multiple Chromophores

Polarization anisotropy is investigated in single porous silicon nanoparticles containing multiple chromophores. Two classes of nanoparticles, low current density and high current density, are studied. Low current density samples exhibit red-shifted spectra and contain only one or two chromophores. High current density particles, on average, contain less than four chromophores and display a blue-shifted spectrum. We utilize single-molecule spectroscopy to probe the polarization effects of the particles, and we show that both classes of particles are influenced by a polarized excitation source. These results are exciting at the fundamental level for understanding coupled quantum dot emitters as well as for applications involving single-photon sources or silicon-based polarization-sensitive detectors.