cssi/SciSciGPT-SciSciNet huggingface dataset:
Decreased tetrahydrobiopterin and disrupted association of Hsp90 with eNOS by hyperglycemia impair myocardial ischemic preconditioning

Cardioprotection by ischemic preconditioning (IPC) is impaired during hyperglycemia, but the mechanisms underlying this phenomenon are poorly understood. This study investigated the role of hyperglycemia to adversely modulate tetrahydrobiopterin (BH(4)) and heat shock protein 90 (Hsp90) during cardioprotection by IPC. Rabbits or mice underwent 30 min of coronary occlusion followed by reperfusion with or without IPC in the presence or absence of hyperglycemia. IPC significantly (P < 0.05) decreased myocardial infarct size (46 ± 1 to 19 ± 2% of the area at risk in control and IPC rabbits, respectively) and increased BH(4) concentrations (HPLC; 7.6 ± 0.2 to 10.2 ± 0.3 pmol/mg protein, respectively), Hsp90-endothelial nitric oxide synthase (eNOS) association (coimmunoprecipitation and Western blotting in mice; 4.0 ± 0.3 to 5.4 ± 0.1, respectively), and the ratio of phosphorylated eNOS/total eNOS. These beneficial actions of IPC on infarct size, BH(4), Hsp90/eNOS, and phosphorylated eNOS were eliminated by hyperglycemia. Pretreatment of animals with the Hsp90 inhibitor geldanamycin (0.6 mg/kg) or the BH(4) synthesis inhibitor diamino-6-hydroxypyrimidine (1.0 g/kg) also eliminated cardioprotection produced by IPC. In contrast, the BH(4) precursor sepiapterin (2 mg/kg iv) restored the beneficial effects of IPC on myocardial BH(4) concentrations, eNOS dimerization, and infarct size during hyperglycemia. A-23871 increased Hsp90-eNOS association (0.33 ± 0.06 to 0.59 ± 0.3) and nitric oxide production (184 ± 17%) in human coronary artery endothelial cells cultured in normal (5.5 mM) but not high (20 mM) glucose media. These data indicate that hyperglycemia eliminates protection by IPC via decreases in myocardial BH(4) concentration and disruption of the association of Hsp90 with eNOS. The results suggest that eNOS dysregulation may be a central mechanism of impaired cardioprotection during hyperglycemia.
Self-sustaining, weakly curved, imploding pathological detonation

Abstract We provide the first theoretical demonstration of the existence of quasi-one-dimensional, quasi-steady, self-sustaining convergent detonation waves. These occur in systems where, in the planar wave, the rate of heat release by chemical reaction reaches a maximum at a point of incomplete reaction. The case examined in the present paper is that for a two-step sequential reaction, with the second stage endothermic. We construct detonation velocity against curvature relationships for converging waves, and compare these theoretical curves with direct numerical simulations of imploding detonations in cylindrical and spherical geometries. We also comment on the one-dimensional stability of imploding and diverging detonation fronts governed by the two-step model.
COMPUTER-AIDED GRAPHICS OF LIQUID-LIQUID EXTRACTION

An algorithm has been developed and tested for steady-state liquid-liquid extraction, using rectangular coordinates. It is capable of handling common types of stagewise contact, i.e., single stage extraction, multistage cross-current, and continuous countercurrent multistage extraction. The results depend on the nature of the extraction scheme and the extent of separation desired. While equilibrium data for some systems are stored in its data bank, the present portable computer simulator ( LIQEXT) has the flexibility of reading equilibrium data for other systems, as well as overriding stored data Both design and rating cases can be performed. In the design mode, i.e., given the feed and solvent rates and the outlet concentration, it calculates the number of stages, the exit stream flow rates, and the concentration profile. In the rating ( or simulation) mode, i.e., given the feed and solvent rates, and the number of stages, it computes the exit streams flow rates and compositions, and the concentration pr...
Consistent flavor naming predicts recognition memory in children and young adults

Abstract The relationship between flavor naming and recognition memory was evaluated in groups of children and young adults who either self-generated flavor names or chose flavor names from a list of four alternatives. The adults were more successful at naming and remembering the flavors, with the age differences in naming performance tending to be larger than differences in memory performance. Differences in recognition memory among the age groups were modest, ranging from 3% to 12%. Providing flavor labels improved naming accuracy, but not naming consistency or memory for younger children (4–7 years old). Labels improved naming accuracy and consistency for the older children (8–11 years old), and showed a trend toward improving memory. Labels improved naming accuracy, consistency and recognition memory in adults. Consistent naming was a powerful predictor of recognition memory for each age group and test condition. Consistently named flavors were remembered correctly on 88% of the trials while inconsistently named flavors showed no evidence of memory. It was concluded that flavor recognition memory and naming consistency were both rooted in successfully matching flavor percepts to a multi-dimensional flavor representation that includes semantic information.
Cleavage resistance of fine-structured materials

Based on a previous bicrystal fracture experiment, the resistance offered by a narrow high-angle grain boundary to cleavage cracking is analyzed theoretically. It is predicted that, when the grain boundary width is smaller than the distance between break-through points, the grain boundary toughness will be highly dependent on the characteristic microstructure length. Analytical expressions are obtained for freestanding thin films and fine-grained materials.
Dynamic Temperature Measurements in Alternatic Current Arcs

Using spectroscopic and high speed data acquisition (less than 5 ?s) techniques, instantaneous measurements of the radial distribution of temperature within atmospheric argon alternating current arcs have been obtained. Incorporation of electronic synchronization methods has permitted such distributions to be determined at any predetermined relative time within the current cycle. The methods described can be applied to phenomena occurring within circuit breaker and switchgear devices. Phase lag between minimum centerline temperature and current zero was observed. The timewise variation of arc radius within the currents cycle was determined.
Factor analyses of the Guilford Zimmerman temperament survey and the Maudsley personality inventory.

(1962). Factor Analyses of the Guilford Zimmerman Temperament Survey and the Maudsley Personality Inventory. The Journal of General Psychology: Vol. 67, No. 1, pp. 21-26.
The Multiple Adaptations of Multiple Imputation

Multiple imputation was first conceived as a tool that statistical agencies could use to handle nonresponse in large-sample public use surveys. In the last two decades, the multiple-imputation framework has been adapted for other statistical contexts. For example, individual researchers use multiple imputation to handle missing data in small samples, statistical agencies disseminate multiply-imputed data sets for purposes of protecting data confidentiality, and survey methodologists and epidemiologists use multiple imputation to correct for measurement errors. In some of these settings, Rubin's original rules for combining the point and variance estimates from the multiply-imputed data sets are not appropriate, because what is known—and thus the conditional expectations and variances used to derive inferential methods—differs from that in the missing-data context. These applications require new combining rules and methods of inference. In fact, more than 10 combining rules exist in the published literatur...
17 beta-estradiol prevents osteopenia in the oophorectomized rat treated with cyclosporin-A.

Cyclosporin-A (CsA) administered to the oophorectomized rat exaggerates the high turnover osteopenia associated with oophorectomy alone. This study investigated whether 17 beta-estradiol replacement could influence the development of osteopenia in the oophorectomized rat treated with CsA. Ninety female Sprague-Dawley rats, approximately 300 g in weight, were divided into 6 groups of 15 each and treated according to the following protocol: group A were sham operated (control), group B underwent oophorectomy (Ox), group C underwent Ox and received CsA (15 mg/kg, by daily gavage) for 28 days (Ox and CsA), group D underwent Ox and received CsA and a 0.1 mg 17 beta-estradiol pellet (EP) implanted sc (Ox, CsA, and EP), group E underwent Ox and received EP (Ox and EP), and group F, which was intact and nonoperated, received CsA (CsA). Rats were weighed and bled on days -7, 0, 7, 14, 21, and 28 for measurement of blood ionized calcium, bone Gla protein (BGP), 17 beta-estradiol, and PTH. Bone histomorphometry was ...
Non-equilibrium phases in laser-processed Fe-0.2 wt.%C-20wt.%Cr alloys

Abstract The microstructures and microhardness of laser-processed Fe-0.2wt.%C-20wt.%Cr alloys were investigated as a function of melt depth in single and multiple (overlapping) laser passes. The single-laser-pass alloys exhibited duplex austenite-ferrite structures with no evidence of carbide precipitation. Melt depths of up to 600 μm did not influence this microstructure. The multiple-laser-pass alloys consisted of lath martensite-ferrite structures in deep (about 600 μm) penetration melts and austenite-ferrite structures in shallow (about 120 μm) penetration melts. The transformation of austenite to martensite in multiple-laser-pass alloys, observed only in deep penetration melts, was explained as due to the effects of tempering temperature, time and quench rate obtained during subsequent laser passes. Conventional furnace heat treatments of single-laser-pass alloys substantiated these conclusions.
Poster: connecting PGAS and traditional HPC languages

Chapel is a high-level parallel programming language that implements a partitioned global address space model (PGAS). Programs written in this programming model have traditionally been self-contained entities written entirely in one language.On our poster, we present BRAID, which enables Chapel programs to call functions and instantiate objects written in C, C++, Fortran 77-2008, Java and Python. Our tool creates language bindings that are binary-compatible with those generated by the Babel language interoperability tool. The scientific community maintains a large amount of code written in traditional languages. With the help of our tool, users will gain access to their existing codebase with minimal effort and through a well-defined interface. The language bindings are designed to provide a good combination of performance and flexibility (including transparent access to distributed arrays).Knowing the demands of the target audience, we support the full Babel array API. A particular contribution is that we expose Chapel's distributed data types through our interface and make them accessible to external functions implemented in traditional serial programming languages.The advantages of our approach are highlighted by benchmarks that compare the performance of pure Chapel programs with that of hybrid versions that call subroutines implemented in Babel-supported languages inside of parallel loops. We also present our vision for interoperability with other PGAS languages such as UPC and X10.
Wind Stress Effects on Detroit River Discharges

Abstract Dynamic flow models are currently used to compute Detroit River discharges for hourly, daily, and monthly time scales. These models include the complete one-dimensional equations of continuity and motion, but neglect the effects of wind stress and ice. The effects of wind stress upon calculated daily and monthly Detroit River discharges are analyzed. The wind effects of several storms with wind setups and surges on Lake Erie were evaluated on an hourly time scale. Inclusion of wind stress terms into the Detroit River models was found to have no significant effect on the monthly flow calculations and on the majority of the daily flow calculations. However, the average monthly effect of −47 m 3 s −1 is equivalent to 111 mm depth of water per month on Lake St. Clair, which may be significant for some Lake St. Clair water balance studies. The effect on Lake Erie is on the order of 5 mm of depth per month, which is not significant for water balance studies. The wind stress was found to be important for daily and hourly flow computations when wind velocities were in excess of about 6 m s −1 .
Design and analysis of quantised coefficient digital filters: application to biomedical signal processing with microprocessors.

Digital filters implemented on microprocessors operate under the constraints of quantisation of data, finite lengths of data words and microprocessor registers, limited arithmetical capability and speed. In view of this, digital filters with integer coefficients have been proposed. We present new techniques that take into consideration quantisation of filter coefficients while still retaining their integer coefficient property. We illustrate this with several applications to ECG signal processing. The paper presents design equations, pole/zero plots, frequency response and analysis of errors for quantised coefficient digital filters. Errors due to quantisation, roundoff, inaccurate coefficient representation and overflow are analysed. Finally, we present an example of a microprocessor-based system.
A Dimensional Approach to Characterizing On-Again/Off-Again Romantic Relationships

To better characterize on-again/off-again (on-off) relationships, the current study examined variations in these relationships using a dimensional approach. Based on a five-typology of on-off relationships, corresponding dimensions were developed and assessed in relation to breakup and renewal negotiations as well as relational quality characteristics. Canonical correlation analyses with 299 participants currently or previously in an on-off relationship revealed two major patterns: (1) positive on-off dynamics (e.g., relationship improvement, maintained interest) were associated with more successful transitions and greater relational quality, and (2) a combination of positive and negative on-off dynamics was related to positive change but also waning interest in the relationship and a greater difficulty negotiating relational transitions. Overall, the current findings suggest certain dimensions play stronger roles in characterizing on-off relationships, and assessing the dimensions in combination (i.e., those that covary in predicting relational characteristics) can reveal insights beyond those provided by categorical classifications of on-off relationships.
Frozen-sectioning yields similar results as traditional methods for fetal cephalic examination in the rat.

Background An integral component of developmental toxicity studies is the evaluation of fetal anatomy, which consists of external, visceral, and skeletal examinations. The visceral examination includes an assessment of the fetal head which, in the rat, is typically completed after chemical fixation. Because chemical fixation requires approximately 7 days, a comprehensive visceral examination, including the head, of the fetal rodent cannot be completed at the time of cesarean section. An alternative method to chemical fixation was desired, whereby one could complete an overall visceral examination at the time of cesarean section. In addition, the method would also have to present fetal cranial structures in a manner consistent with that derived after chemical fixation. Methods Pregnant Sprague–Dawley rats were administered either 6-aminonicotinamide (6AN), 6 or 12 mg/kg on gestation day 13, or all-trans retinoic acid (RA) 5 or 25 mg/kg on gestation days 9 and 10, untreated dams served as a control group. On gestation day 20, fetuses were sacrificed and removed via cesarean section and one-half of the fetuses from each litter were placed in Bouin's solution (chemical fixation) and the remaining fetuses maintained under refrigeration until just before frozen tissue preparation (freeze fixation). Sectioning of the fetal head was similarly conducted after either chemical or frozen-fixation. Fetal cranial findings observed after chemical fixation were compared to those observed after frozen-fixation in the untreated control and 6AN and RA-treated groups. Results The incidence and severity of the cranial findings, including effects on the eye, brain, and palate, were similarly observed, regardless of fixation method. Conclusions A frozen sectioning method for evaluation of the fetal head, yielding results comparable to those derived after chemical fixation, is described. This procedure provides a viable alternative to chemical fixation, and allows the teratologist to complete a comprehensive fetal visceral examination at the time of cesarean section. Teratology 66:77–84, 2002. © 2002 Wiley-Liss, Inc.
Exploring the photorefractive effect in polymer-dispersed liquid crystals using near-field scanning optical microscopy

Static and dynamic near-field scanning optical microscopy (NSOM) methods are used to study physical phenomena associated with photorefractivity in dye-doped polymer dispersed liquid crystals (PDLCs). Micrometer-sized liquid crystal droplets doped with perylene and N,N'-dioctyl-1,4,5,8-naphthalene diimide (NDI) dyes, which serve as the photoexcitable electron donor and acceptor, respectively, are studied. The droplets are encapsulated within a thin poly(vinyl alcohol) film. Simultaneously recorded topographic, fluorescence, and birefringence NSOM images show the films to be morphologically complex, containing ellipsoidal and collapsed ellipsoidal droplets. The presence of the collapsed droplets suggests the dissolved dyes may be surface active. Nevertheless, the NSOM images prove the vast majority of dye is contained within the well-defined liquid crystal droplets. Data on the local ion migration and liquid crystal reorientation dynamics is obtained by dynamic NSOM imaging methods. A sinusoidally modulated electric field is applied across the sample, between the aluminized NSOM probe and the electrically conductive film substrate. Lockin detection of the modulated optical signal resulting from field-induced liquid crystal reorientation is used to obtain amplitude and phase images of the sample. Comparison of the images recorded before, during, and after photogeneration of ions shows spatial variations in the relative importance of ion generation and migration on the liquid crystal orientation state. Computer simulations of the field-dependent ion migration dynamics and the liquid crystal response are used to better understand the data obtained.
Treatment of Disability in Peripheral Arterial Disease: New Drugs

Peripheral arterial disease is a major manifestation of systemic atherothrombosis that affects a large segment of the adult population. The major treatment goals for this population are to address the marked increase risk in cardiovascular events and then secondarily to treat the disability and reduced exercise tolerance. The primary goals for treating the limb symptoms of PAD are to improve functional capacity, exercise performance and qualify of life. Exercise training in a formal setting, revascularization with angioplasty and cilostazol all have proven efficacy. In addition, there is a major interest in developing new pharmacologic therapies for claudication. Prostaglandins have been utilized for critical leg ischemia for decades, but recent trials have not demonstrated any role for these drugs in treating claudication. Carnitine and its derivatives (propionyl-L-carnitine) have been shown to improve treadmill exercise performance and quality of life. These drugs also have an excellent safety profile. A final promising class of drugs is statins that not only reduce the increased risk of ischemic events but also appear to improve claudication symptoms.
Tight-Binding study of Boron structures

Abstract We have performed Linearized Augmented Plane Wave (LAPW) calculations for five crystal structures (alpha, dhcp, sc, fcc, bcc) of Boron which we then fitted to a non-orthogonal tight-binding model following the Naval Research Laboratory Tight-Binding (NRL-TB) method. The predictions of the NRL-TB approach for complicated Boron structures such as R105 (or β-rhombohedral) and T190 are in agreement with recent first‐principles calculations. Fully utilizing the computational speed of the NRL-TB method we calculated the energy differences of various structures, including those containing vacancies using supercells with up to 5000 atoms.
Personal History, Intelligence, and Academic Achievement

Resume Les notations de l'histoire personnelle prisentees ici contiennent 169 parties choisies de divers Inventaires psychonevrosiques et questionnaires psychiatriques. Quatre-vingt-dix-neuf parties (Forme I) ont ete employees comme echelle graphique d'evaluation, les autres (Forme II) exigeaient la reponse Oui ou Non. Alors on a correle l'un avec l'autre les resultats sur chacune des notations, les notations du rendement du premier semestre, celui du second semestre, et celles des tests d'intelligence. On a compute les měmes series de correlations pour les hommes et les femmes. Les coefficients de correlation des variables etudies ne montrent aucunes differences importantes entre les sexes comme groupes. II existe cependant des differences individuelles importantes. Ces differences individuelles ont ete d'une grande valeur pour l'emploi clinique puisqu'elles ont fait decouvrir vite les facteurs generaux et specifiques d'une mauvaise adaptation par celui qui s'en sert. Les correlations entre les notations...
Long-Term Survival after Autologous Bone Marrow Transplantation for Follicular Lymphoma in First Remission

Abstract The role of autologous stem cell transplantation (ASCT) in the treatment of follicular lymphoma is still being defined in the era of antibody therapy. Here we report the long-term 12-year clinical outcomes of patients treated with autologous bone marrow transplantation (ABMT) for follicular non-Hodgkin's lymphoma (NHL) in first remission. Between 1988 and 1993, advanced-stage follicular NHL patients in need of initial therapy were enrolled in 2 consecutive prospective treatment trials of either standard-dose CHOP induction (83 patients) or high-dose CHOP plus granulocyte-colony stimulating factor (G-CSF) (20 patients). Patients who achieved an adequate remission with induction therapy underwent conditioning with cyclophosphamide and total body irradiation (TBI) followed by ABMT in first remission using bone marrow (BM) purged in vitro with anti-B cell monoclonal antibodies and rabbit complement (96 patients). At 12-year follow-up, 61% of the patients are alive and 43% remain in continuing complete remission. The only predictors of decreased progression-free survival proved to be histologic BM involvement at time of harvest (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.3-3.9, P
The effects of pulsatile cardiopulmonary bypass on cerebral and renal blood flow in dogs

Abstract Objective: The purpose of this study was to determine the effects of pulsatility on cerebral blood flow, cerebral metabolism, and renal blood flow over a range of cardiopulmonary bypass temperature and flow conditions. Design/Setting: The investigation was prospective, randomized, and performed in a canine physiology laboratory at the Mayo Foundation. Participants and Interventions: Anesthetized dogs were studied during pulsatile (n = 9) or nonpulsatile (n = 10) cardiopulmonary bypass at two flow rates (2.4 and 1.2 L/min/m2) at each of three temperatures (37°, 32°, and 27°C). Pulsatility was achieved by use of a pediatric intraaortic balloon pump. Cerebral blood flow and metabolic rate were determined using the sagittal sinus outflow method. Renal blood flow was determined by a periarterial ultrasonic flow probe. Measurements and Main Results: In the pulsatile group, a pulse pressure of 29 mmHg had no effect on cerebral blood flow or metabolism at any temperature under either flow condition. Renal blood flow was also unaffected by pulsatility, but decreased with hypothermia and reduced pump flow. Pulsatility also did not attenuate the systemic effects of normothermic hypoperfusion. Conclusions: Pulsatility has no significant effect on cerebral or renal perfusion over a broad range of cardiopulmonary bypass temperature and flow conditions. Cerebral blood flow and metabolism were functions of temperature but not pulsatility or flow rate. Renal blood flow was affected by both temperature and cardiopulmonary bypass flow rate but not by pulsatility. Finally, central nervous system perfusion may be preserved under low-flow cardiopulmonary bypass conditions by shunting of perfusion from splanchnic vascular beds.
Littoral chironomid communities in an arctic Alaskan lake

The soft-sediment littoral zone of arctic Toolik Lake (68°N) is composed of patches of macrophytes and bare sediments, which support distinct communities of chironomid larvae. Macrophytes were typically dominated by Stictochironomus rosenschoeldi (Zett.) but also had persistent populations of Heterotrissocladius maeaeri Brund., Paratanytarsus spp., Ablabesmyia sp., as well as several other less common taxa. Bare sediments were dominated by H. maeaeri, Parakiefferiella sp., and Zalutschia zalutschicola Lip. S. rosenschoeldi was common in bare sediments hut far less so than in macrophytes. Few taxa were restricted to either habitat. Life cycle lengths, estimated for some species, ranged from 1 to 4 yr. Analysis of indicator species suggested that Toolik is oligotrophic to ultra-oligotrophic, which is consistent with the available primary production estimate for Toolik Lake. Littoral chironomid communities, in addition to profundal communities, may be useful in lake typology.
Electrophysiological and behavioral effects of blockade of the nonspecific thalamo-cortical system

Abstract A thalamo-cortical system with origins in the midline nonspecific thalamic nuclei and projections to the orbitofrontal granular cortex has been identified with an electrocortical synchronizing function related to internal inhibition. 30 acute and 14 chronic cat preparations have been utilized in the study of the nonspecific thalamo-cortical system, including its origins, pathways and cortical projections. Its functional role has been assessed in terms of its effect upon spindle bursts, recruiting and augmenting responses, sensory evoked potentials and the performance of certain learned behavioral tasks. Interruption of this nonspecific thalamo-cortical system has been produced by lesions or reversible cryogenic blockade, and by cortical ablations at 3 principal sites: n. ventralis anterior, the inferior thalamic peduncle (ITP), and the orbitofrontal cortex. Blockade of this thalamo-cortical synchronizing mechanism has resulted in 3 effects: (1) Reduction or abolition of recruiting responses elicited by stimulation of the midline thalamic nuclei, and reduction or abolition of spontaneous spindle bursts produced by lesion of the mesencephalic reticular formation. These effects involving the nonspecific thalamo-cortical system are contrasted with the specific sensory and motor systems whose augmenting responses are not affected by blockade of the thalamo-cortical system. (2) Enhancement of visual cortical responses elicited by photic or optic tract stimulation. This effect upon specific sensory responses contrasts with the reduction or abolition of spindle bursts and recruiting responses mediated by a nonspecific system. (3) Deficits in performance of learned behavioral tasks involving bar-pressing and single alternation. Complete cryogenic blockade in ITP interrupted bar-pressing whereas partial blockade only slowed bar-pressing rate but interfered with single alternation performance due to perseveration. The nonspecific thalamo-cortical system has been discussed in terms of its synchronizing and regulating influences upon electrocortical activity, its inhibitory role, and as a possible mechanism mediating attention and inattention.
Validation of the pneumonia severity index. Importance of study-specific recalibration.

OBJECTIVE: To evaluate the predictive validity and calibration of the pneumonia severity-of-illness index (PSI) in patients with community-acquired pneumonia (CAP). PATIENTS: Randomly selected patients (n=1,024) admitted with CAP to 22 community hospitals. MEASUREMENTS AND MAIN RESULTS: Medical records were abstracted to obtain prognostic information used in the PSI. The discriminatory ability of the PSI to identify patients who died and the calibration of the PSI across deciles of risk were determined. The PSI discriminates well between patients with high risk of death and those with a lower risk. In contrast, calibration of the PSI was poor, and the PSI predicted about 2.4 times more deaths than actually occurred in our population of patients with CAP. CONCLUSIONS: We found that the PSI had good discriminatory ability. The original PSI overestimated absolute risk of death in our population. We describe a simple approach to recalibration, which corrected the overestimation in our population. Recalibration may be needed when transporting this prediction rule across populations.
Use of sunfish and stoneroller minnows as real-time in situ biomonitors of PCB contamination in freshwater streams.

A long-term polychlorinated biphenyl (PCB) monitoring study was conducted fortwo moderately impacted freshwater streams in Kentucky. Streamwater, sediment, and fish were analyzed for Aroclors 1248, 1254, and 1260 during 1988-2005. Only 8 of 263 water samples showed detectable PCBs. The low occurrences of PCB detections in streamwater indicated that PCBs were transitory in the water column, rapidly mobilizing into biotic and sediment compartments. One component of this study focused on species-specific patterns of PCB residues in fish, especially the green sunfish (Lepomis cyanellus), longear sunfish (L. megalotis), bluegill (L. macrochirus), and stoneroller minnow (Campostoma anomalum). Stoneroller minnows had higher PCB concentrations and increased frequency of detection when compared to sport fish. Aroclor 1248 was detected 80% of the time in stoneroller minnows from Big Bayou creek, whereas it was only detected in 25-39% of sport fish. In comparison, Aroclors 1254 and 1260 in sport fish were detected 49-69% of the time. These results indicate that higher chlorinated PCB congeners found in Aroclors 1254 and 1260 were not as readily metabolized and excreted by sport fish. No relationships were found between sunfish age and PCB concentrations, which demonstrated that sunfish exposed to low PCB contamination can effectively regulate PCBs, regardless of age. In addition, at low PCB levels (<0.50 μg/g), green sunfish body burden did not correlate with lipid content. A certain PCB threshold concentration, ≥1.00 μg/g, must be exceeded before correlations between PCB body burden and lipid content are observed. These results indicate that, at least for species such as the sunfish, the use of the octanol-water partition coefficient (K ow ) under low-level PCB exposure would appear to have little predictive value. Studies by Sanborn et al. (1975) found the green sunfish to be particularly adept at metabolizing organochlorine compounds and PCBs. This field study supports their laboratory findings. Green sunfish may have an enhanced P450 system, or due to low body lipid content, more effectively shunt PCBs into metabolic pathways that detoxify these compounds.
Approach to automated screening of mammograms

This paper describes an adaptive image segmentation method that detects cancerous changes in mammograms. A mammogram containing abnormal signs changes is segmented into 'suspicious regions' and normal tissue. The method employs hierarchical region growing that uses pyramidal multiresolution image representation. The relationships between pixels at different resolution levels are established using a fuzzy membership function, thus enabling detection of very small and/or low contrast details in highly textured background. The paper discusses two versions of the method, the first is aimed at detection of microcalcifications, and the second at detection of benign and malign nodules. Both versions are fully automated and differ in selection of parameters of the fuzzy membership function. The algorithm was evaluated using synthetically generated objects superimposed on normal mammograms, and real mammograms. Based on this evaluation, the method has potential to be used as an aid to medical experts in establishing the correct diagnosis.
The Alaska Education and Research Towards Health (EARTH) Study: Cancer Risk Factors

The Alaska Education and Research Towards Health (EARTH) Study assessed cancer risk among 3,821 Alaska Native people (AN). We present the prevalence of selected cancer risk factors and comparison with Healthy People 2010 goals. Participants completed extensive computer-assisted self-administered questionnaires on diet, physical activity, tobacco and alcohol use, cancer screening, family history of cancer, and environmental exposures. Measurement data were collected on blood pressure, height, weight, waist/hip circumference, fasting serum lipids, and glucose. Cancer risk factors are high for the Alaska EARTH study population. For all risk factors studied except for vegetable consumption, Alaska EARTH Study participants did not meet Healthy People 2010 goals. This study is unique in providing questionnaire and measurement data of cancer risk factors on a larger study sample than any previous study among AN living in Alaska. Data show that the prevalence of most cancer risk factors exceeded national recommendations. Given the disease disparities that exist for the AN population, these data provide important baseline data that can be used to target health interventions and reduce health disparities.
Utilizing a 24-Hour Dietary Recall and Culturally Specific Diabetes Education in Mexican Americans With Diabetes

Two objectives were established for this study: 1) to assess the impact of a culturally specific, intensive diabetes education program on dietary patterns, and 2) to assess nutrient consumption relative to the Recommended Dietary Allowances. The study population consisted of elderly Mexican Americans with diabetes living in Harlingen and Brownsville, Texas. The experimental group (n=78) participated in an intense, 2-hour nutrition education session, while the control group (n=74) did not. The education session was conducted for groups of eight subjects via videotapes and interactive discussion. All groups experienced significant weight loss except the women in the experimental group. After the education program, however, the experimental women had increased the percentage of calories consumed daily from carbohydrate. Mean calcium consumption was substantially less than the RDA in all groups, and inadequate amounts of ascorbic acid and vitamin A often were consumed. Intensive, frequent, long-term follow-up...
Counseling Women Who Have Experienced Pregnancy Loss: A Review of the Literature

The authors review pregnancy loss scholarly literature and discuss themes of silence, grief, psychological distress, role of social support, satisfaction with health care, and coping strategies from a counseling standpoint. Counseling needs of women who have experienced pregnancy loss are delineated, and recommendations for future research in this area are made.
A tessellation algorithm for the representation of trimmed nurbs surfaces with arbitrary trimming curves

Abstract In most cad systems, a trimmed parametric surface is defined by two things: the control information of the surface itself and the control information of its trimming curves, which are usually defined as parametric curves in the parameter space of the surface. Often, trimmed parametric surfaces cause problems in the context of data exchange between cad systems, surface evaluation/rendering, and grid/mesh generation. This paper describes a new approach for representing a trimmed surface. The approach is based on the idea of decomposing the valid part of the parameter space of a trimmed surface by a set of planar, ruled surfaces, which are defined in parameter space and whose union defines the entire valid part. A generalized Voronoi diagram is constructed for the set of trimming curves in parameter space. This diagram defines tiles around each trimming curve, which are further tessellated by utilizing a scan line technique for identifying and filling the interior of polygons. Here, the scan line technique is used to extract non-horizontal segments of the given trimming curves. Pairs of these segments are then linearly interpolated in horizontal parameter direction, thus defining a set of planar, ruled surfaces. The set of all these planar, ruled surfaces defines the entire valid part of a trimmed surface exactly.
Leaving the herd: The lingering threat of difference for same-sex desires in postcommunist Russia

This article reports on a study that explored how living during the transition from a Soviet system to a postcommunist society affected gay, lesbian, bisexual, and transgender (GLBT) people in Russia. A grounded theory method was used to analyze the interviews of 10 Russian GLBT individuals. The core category, leaving the herd— the lingering threat of difference in postcommunist Russia, reflected how dangerous perceived difference of any kind remains for those living in a country where, traditionally, standing out has had consequences ranging from social ostracization to prison sentences. Results also addressed the advantages and disadvantages of invisibility for GLBT Russians, the effects of globalization on the GLBT community in Russia, and uncertainty about the future. Clinical and research implications of the study are discussed.
Selectivity bias correction methods in polychotomous sample selection models

Abstract Polychotomous sample selection models include multinomial choice models and models with multiple rules for sample inclusion. The author analyzes two standard parametric approaches to selectivity bias correction in such models - the Lee and Generalized Heckman (GH) methods. The paper's main point is that Lee's approach, unlike GH, requires strong implicit restrictions on covariances between outcomes and selection indices. A Monte Carlo study demonstrates (1) that the Lee estimator exhibits significant bias when the data-generating process does not conform to its implicit covariance assumptions, and (2) that the GH estimator may have high variance due to multicollinearity between regressors.
Heavy-quark fragmentation functions in a simple string model

Abstract We model QCD confinement by using the massless relativistic string that decays according to a simple covariant Poisson law. We explore the implications of the model and arrive at a heavy-quark fragmentation function which depends on only one parameter. We compare the resulting fragmentation function with data and other models and show how, unlike other string-based model, it exhibits the limiting behavior expected from general kinematic arguments and perturbative QCD.
Behavioral characterization of A53T mice reveals early and late stage deficits related to Parkinson's disease.

Parkinson's disease (PD) pathology is characterized by the formation of intra-neuronal inclusions called Lewy bodies, which are comprised of alpha-synuclein (α-syn). Duplication, triplication or genetic mutations in α-syn (A53T, A30P and E46K) are linked to autosomal dominant PD; thus implicating its role in the pathogenesis of PD. In both PD patients and mouse models, there is increasing evidence that neuronal dysfunction occurs before the accumulation of protein aggregates (i.e., α-syn) and neurodegeneration. Characterization of the timing and nature of symptomatic dysfunction is important for understanding the impact of α-syn on disease progression. Furthermore, this knowledge is essential for identifying pathways and molecular targets for therapeutic intervention. To this end, we examined various functional and morphological endpoints in the transgenic mouse model expressing the human A53T α-syn variant directed by the mouse prion promoter at specific ages relating to disease progression (2, 6 and 12 months of age). Our findings indicate A53T mice develop fine, sensorimotor, and synaptic deficits before the onset of age-related gross motor and cognitive dysfunction. Results from open field and rotarod tests show A53T mice develop age-dependent changes in locomotor activity and reduced anxiety-like behavior. Additionally, digigait analysis shows these mice develop an abnormal gait by 12 months of age. A53T mice also exhibit spatial memory deficits at 6 and 12 months, as demonstrated by Y-maze performance. In contrast to gross motor and cognitive changes, A53T mice display significant impairments in fine- and sensorimotor tasks such as grooming, nest building and acoustic startle as early as 1–2 months of age. These mice also show significant abnormalities in basal synaptic transmission, paired-pulse facilitation and long-term depression (LTD). Combined, these data indicate the A53T model exhibits early- and late-onset behavioral and synaptic impairments similar to PD patients and may provide useful endpoints for assessing novel therapeutic interventions for PD.
Insurgency, counterinsurgency, and the rational peasant

Many rational choice treatments of guerrilla insurgency have focused on the strategic calculus by which government and insurgent elites use the tactical weapons of coercion and benefits to win the support of nonelites. This paper uses Frohlich and Oppenheimer's model of the rational tax payer/tax evader to develop a model of the decision calculus by which nonelites respond to the tactical behavior of elites and thereby choose between supporting the incumbent regime, its insurgent opposition or neither. This model is then used to assess the likely impact of various insurgent and counterinsurgent tactics on nonelite support and loyalty.
Distortion reduction for fast soft straightening of the colon

Rationale and Objectives. The purpose of this study was to suppress the geometric distortion associated with soft straightening of the colon by moderately adjusting curved cross sections, which is equivalent to appropriately modifying the underlying electrical field. Materials and Methods. A computational mechanism to reduce the geometric distortion associated with soft straightening was developed. Because the cause of distortion is uneven sampling of the colon wall with curved cross sections, the curved cross sections formed according to a numerically simulated electrical field were redistributed in the distortion reduction process. This mechanism can be directly incorporated into a previously published fast soft-straightening algorithm. Simulations were performed to evaluate the effectiveness of the mechanism, and a phantom colon with digitally implanted, spherical polyps was straightened and rendered to visually display the efficacy of the mechanism. Results. The distortion reduction mechanism was advantageous regarding shape preservation of polyps and alleviated distortion substantially. The mechanism occupied only a small portion of the total processing time. Conclusion. The distortion reduction mechanism can effectively reduce the geometric distortion associated with soft straight-ening at little computational cost and has potential for use with computed tomographic colonography.
Arachidonic acid, ARC channels, and Orai proteins.

Abstract A critical role for arachidonic acid in the regulation of calcium entry during agonist activation of calcium signals has become increasingly apparent in numerous studies over the past 10 years or so. In particular, low concentrations of this fatty acid, generated as a result of physiologically relevant activation of appropriate receptors, induces the activation of a unique, highly calcium-selective conductance now known as the ARC channel. Activation of this channel is specifically dependent on arachidonic acid acting at the intracellular surface of the membrane, and is entirely independent of any depletion of internal calcium stores. Importantly, a specific role of this channel in modulating the frequency of oscillatory calcium signals in various cell types has been described. Recent studies, subsequent to the discovery of STIM1 and the Orai proteins and their role in the store-operated CRAC channels, have revealed that these same proteins are also integral components of the ARC channels and their activation. However, unlike the CRAC channels, activation of the ARC channels depends on the pool of STIM1 that is constitutively resident in the plasma membrane, and the pore of these channels is comprised of both Orai1 and Orai3 subunits. The clear implication is that CRAC channels and ARC channels are closely related, but have evolved to play unique roles in the modulation of calcium signals—largely as a result of their entirely distinct modes of activation. Given this, although the precise details of how arachidonic acid acts to activate the channels remain unclear, it seems likely that the specific molecular features of these channels that distinguish them from the CRAC channels – namely Orai3 and/or plasma membrane STIM1 – will be involved.
A Map of Whitman's Washington Boarding Houses and Work Places

Offers a list and description of the places Whitman resided and worked in while living in Washington, D.C.; accompanied by a map reproduced on the back cover of this issue.
Impedance of reinforcing steel with disbonded dual polymer–zinc coating

Abstract Dual polymer/zinc-coated concrete steel reinforcing bar (rebar) is a novel material intended to improve corrosion related durability in marine and deicing salt environments. Severe fabrication bending induces coating breaks and separation from the steel substrate, creating a crevice where some zinc corrosion takes place. EIS measurements to characterize that corrosion revealed spontaneous fluctuations that included variations in the size of the high frequency loop and sometimes strong intermediate frequency dispersion. This investigation examined the underlying causes for that behavior. The fluctuations were explained by formation and episodic release of hydrogen gas in the crevice underneath the disbonded coating, as a product of the cathodic reaction in corrosion of the zinc layer. The gas caused partial occlusion of the crevice and the crevice opening at tears in the coating. Gas occlusion increased the effective electrolytic resistance inside the crevice, and contributed to an enhanced transmission line configuration with associated frequency dispersion, especially notable in the intermediate frequency part of the impedance spectrum. A radial transmission line model was adopted as a simplified abstraction of the system. Properties of the radial transmission line impedance behavior are discussed. The model output replicated the key features of the measured impedance spectrum and its fluctuations, and permitted isolating the low frequency response as the most representative to evaluate corrosion conditions inside the crevice in subsequent research.
A variational coupled-mode theory for periodic waveguides

A simple variational theorem for the dispersion relations and propagation constants of periodic waveguides is derived. The trial fields used in the variational formula incorporate all the Floquet components correct to first order. This yields a propagation constant in which errors enter only to fourth order in the trial field. The analysis yields a new coupled mode formulation which is shown to yield excellent agreement with exact analytic solutions (in l-D), and numerical simulations (in 2-D), for high-index contrast structures.