cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of propionyl-carnitine on mitochondrial respiration and post-ischaemic cardiac function in the ischaemic underperfused diabetic rat heart.

Background and objective: Carnitine and its derivatives, namely propionyl-carnitine (PC), have been shown to protect cardiac metabolism and function in diabetes mellitus and ischaemic heart disease. Since diabetes is associated with abnormalities in mitochondrial metabolism of fuels, we examined the effects of PC on mitochondrial respiration in ischaemic hearts from streptozotocin-diabetic rats. Methods: Diabetes was induced in Sprague-Dawley rats by an intravenous injection of streptozotocin. Following the diagnosis of diabetes, oral PC treatment was initiated for a period of 6 weeks. After treatment, cardiac function was determined from working hearts perfused under aerobic conditions and in a separate group of hearts subjected to ischaemia and reperfusion. Mitochondrial respiration was determined under aerobic conditions and following low-flow ischaemia. Results: Rates of state 3 mitochondria respiration with pyruvate were significantly lower in diabetic (n = 4) hearts compared with control (n = 6) hearts (80 ± 5 vs 112 ± 5 nanoatoms O2/mg protein/min, respectively), but those with palmitoylcarnitine were similar (101 ± 11 vs 106 ± 6 nanoatoms O2/mg protein/min). Diabetic rat heart (n = 8) function, expressed as rate pressure product, was also significantly decreased compared with control (n = 8) hearts (21.5 ± 1.0 vs 29.5 ± 0.9 beats × mm Hg × 10−3/min, respectively). In PC-treated diabetic (n = 6) hearts, state 3 respiration with pyruvate was increased, and a marked improvement in left ventricular function from 21.5 ± 1.0 to 26.0 ± 0.6 beats × mm Hg × 10−3/min was observed. During low-flow ischaemia, state 3 respiration with pyruvate remained lower in diabetic (n = 5) hearts compared with control (n = 5) hearts (64 ± 3 vs 46 ± 5 nanoatoms O2/mg protein/min, respectively). Following treatment with PC (n = 4), however, respiration with this substrate was significantly increased to 57 ± 4 nanoatoms O2/mg protein/min. PC was also associated with a significant improvement in cardiac function in reperfused diabetic rat (n = 4) hearts (18.4 ± 0.2 beats × mm Hg × 10−3/min). Conclusion: Our results showed that PC has a beneficial effect on cardiac function and increases ischaemic tolerance of the diabetic rat heart. This beneficial effect of PC can be explained, in part, as an improvement in mitochondrial metabolism of pyruvate during the actual ischaemic period.
Rationing critical care medicine: recent studies and current trends.

Purpose of review This paper reviews the literature on the rationing of critical care resources. Recent findings Although much has been written about the concept of rationing, there have been few scientific studies as to its prevalence. A recent meta-analysis reviewed all previously published studies on rationing access to intensive care units but little is known about practices within the intensive care unit. Much literature in the past few years has focused on the growing use of critical care resources and projections for the future. Several authors suggest there may be a crisis in financial or personnel resources if some rationing does not take place. Other papers have argued that the methods of rationing critical care previously proposed, such as limiting the care of dying patients or using cost-effectiveness analysis to determine care, may not be effective or viewed as ethical by some. Finally, several recent papers review how critical care is practiced and allocated in India and Asian countries that already practice open rationing in their health care systems. Summary There is currently no published evidence that overt rationing is taking place in critical care medicine. There is growing evidence that in the future, the need for critical care may outstrip financial resources unless some form of rationing takes place. It is also clear from the literature that choosing how to ration critical care will be a difficult task.
Optimization using iterative design techniques

Abstract A scheme is presented whereby a designer can achieve an optimal design by performing successive reanalyses (iterative design) using at each step the proper stiffness matrix. The scheme is applied to sandwich plate and frame design problems.
Neuropeptide Y stimulates luteinizing hormone-releasing hormone release from superfused hypothalamic GT1-7 cells.

The effects of neuropeptide Y (NPY) on LHRH release from an immortalized cell line were investigated using a flow-through cell culture superfusion system. Immortalized hypothalamic GT1-7 cells were cultured for 72 h and superfused for a total of 180 min. In initial experiments, discrete 5-min pulses of NPY (10(-12)-10(-5) M) were administered to the cells. A clear dose-dependent stimulatory effect on NPY on LHRH release from the cells was observed with a calculated 50% effectiveness concentration of 33 nM. The stimulatory effects of brief NPY exposure were rapid and robust, e.g. reaching and maintaining levels of 173% over baseline for 20 min at the 10(-7) dose. The lowest dose of NPY that showed a significant effect was 10(-10) M; maximal responses were observed at 10(-6) M and reached a plateau thereafter. Control pulses of Dulbecco's modified Eagle's medium (DMEM) and 10(-6) M substance P or arg-vasopressin were also presented to the cells to serve as controls for our pulse protocol, and these challenges produced no significant LHRH responses. The NPY receptor antagonists, PYX1 and PYX2, at 10(-8) M, completely blocked the observed NPY responses in these cells. To assess the NPY receptor subtypes that mediate the NPY effects pharmacologically, GT1-7 cells were challenged with a Y1 receptor agonist, (Leu31Pro34)NPY, a Y2 receptor agonist, NPY(13-36), or peptide YY, at doses 10(-12)-10(-5) M. All four peptides stimulated LHRH release from GT1-7 cells with a rank-ordered potency of NPY = peptide YY > Y1 agonist = Y2 agonist. To examine possible signal transduction mechanism(s) involved in mediating this effect, pertussis toxin, RpcAMPs (cyclic adenosine-3'5'-monophosphothioate Rp diastereomer), Ca(2+)-free DMEM and TMB-8 (3, 4, 5-trimethoxybenzoic acid 8-(diethylamino) octylester) were used to treat the cells before and during superfusion with NPY. Treatment with pertussis toxin, RpcAMPs, and Ca(2+)-free DMEM did not significantly alter NPY-stimulated LHRH release responses to 10(-7) M NPY. However, the addition of 100 microM and 250 microM TMB-8 to Ca(2+)-free DMEM almost completely blocked this NPY effect, as did 10 microM ryanodine. Finally, the locus of action for this NPY effect was examined using tetrodotoxin to reduce action potential propagation in the GT1-7 cells. Tetrodotoxin treatment blocked the LHRH response to NPY by more than 50%.(ABSTRACT TRUNCATED AT 400 WORDS)
Spectroscopic Examination of Protein Adsorption from Seawater onto Titanium

Several noninvasive optical and electrochemical techniques were adapted to examine partitioning of protein from seawater onto polished titanium with the use of the plant enzyme ribulose-1,5,-bisphosphate carboxylase-oxygenase (Rubisco) as a model. Protein films, varying in surface concentrations from 0.011 to 3.606 μg cm−2, were prepared by exposing polished Ti surfaces to seawater amended with 0.04-90.80 μg mL−1 of 3H-Rubisco. Mean film thickness, d, measured by ellipsometry, increased linearly over most of the range of irreversibly bound protein (Γirr = 0.011-2.491 μg cm−2). Spatial coverages of the films were more heterogeneous at low surface coverages, indicative of heterogeneous adsorption resulting in barren Ti oxide surface sites and insular protein clusters. The thickness of the underlying Ti oxide layer, also measured by ellipsometry, was highly variable and indicated that oxidation of the surface was suppressed at high protein coverages during two-hour exposures to seawater. Vibrational spectra of surface films, from submonolayer (0.03 μg cm−2) to multilayer (3.61 μg cm−2), were obtained with the use of Fourier transform infrared reflection-absorption spectrometry (FT-IRAS). Peak areas of amide I and II bands varied linearly with Γirr, permitting noninvasive measurement of protein mass at the surface. Relative intensities of the amide II/amide I bands, band composition of the amide III, and peak frequencies varied with surface concentration, indicating unfolding of adsorbed proteins. Vibrational spectroscopic and ellipsometric evidence suggests that protein structure is most altered at low surface concentrations. Electrochemical impedance spectroscopy (EIS) performed from 100 μHz to 100 kHz on replicate test surfaces revealed that the electrochemical behavior of the titanium/protein interface was consistent with that of a parallel RC circuit. The charge transfer resistance, Rct, of the interface varied as a two-state function of protein concentration. The Rct increased more rapidly within the monolayer domain (0.12 to 2.8 MΩ cm2) than in the multilayer domain (2.8 to 4.9 MΩ cm2), indicating that impedance to electron flow across the interface is most influenced by protein monolayer formation and is less affected by additional layers. Estimations of rates of oxidation or dissolution of the substratum were inversely proportional to protein surface concentrations. Together these techniques provide internally consistent measurements of surface film thickness, adsorbate mass, gross chemical composition, interface organization, electrical impedance, capacitance, and oxide layer thickness. These data are useful for determining the physical state of the interface, its dynamics, and the potential oxidation rates of the substratum underlying the surface film.
Positive Psychology at the Summit

Psychology has traditionally placed more emphasis on the negative than positive aspects of human behavior. The positive psychology movement, since its beginnings in 1999, has made major advances toward correcting this imbalance. Research inspired by the movement now spans an impressive range of topics, including many that are absolutely essential to a comprehensive psychological understanding of human nature. The present special issue provides a sampling of some of the best work in the area. All but the first and last articles come from presentations at the Second International Positive Psychology Summit, held in 2003 in Washington, DC. This sample can be supplemented by the chapters that have appeared in several recent anthologies of contemporary research.
Modelling Individuals Employing an Integrated Energy Response: Application to Daphnia

Motivated by problems where variation among individuals is necessary to explain properties of ecological systems, we develop a mathematical model of an individual organism. The model, based primarily upon energetics, is developed specifically for female daphnids, although with appropriate modifications it should be applicable to other aquatic animals such as fish. Mimicking the life history of an individual as it progresses from egg to juvenile to adult instars, the model consists of a coupled pair of nonlinear, nonauton- omous ordinary differential equations. The growth of an individual is described through the dynamics of two compartments-lipid and structure-of the organism because of the importance of lipid dynamics in aquatic animals. Energy supply and demand are handled through an energy integrator compartment. Availability of energy is represented by potential flows from the lipid and structural compartments. Energy requirements of maintenance, activity, and reproduction are the sinks. An advantage of employing an individual-based technique is that ample information relating to the individual parameters-most of which are physiological in character-can usually be obtained, and reasonable estimates for model application found.
High-Efficiency Incorporation in Vivo of Tyrosine Analogues with Altered Hydroxyl Acidity in Place of the Catalytic Tyrosine-14 of Δ5-3-Ketosteroid Isomerase of Comamonas (Pseudomonas) testosteroni: Effects of the Modifications on Isomerase Kinetics†

Versions of the Y55F/Y88F modified form of Δ5-3-ketosteroid isomerase in which the active-site tyrosine-14 is replaced by 2-fluorotyrosine, 3-fluorotyrosine, and 2,3-difluorotyrosine, amino acids having progressively greater acidity of their phenolic hydroxyls, have been expressed in an Escherichia coli host and purified to high homogeneity. The steady-state kinetic properties of Y55F/Y88F KSI and its fluorotyrosine modified forms have been determined. The mechanistic implications of the results are presented and discussed.
Histomorphometric analysis of intramyocardial vessels in primary and senile amyloidosis: epicardium versus endocardium.

Abstract Background The literature is unclear as to the frequency and degree of vascular involvement among the various types of cardiac amyloidosis, specifically the senile type. Methods We analyzed the intramyocardial vascular involvement, both qualitatively and quantitatively, in 18 patients with autopsy-proven cardiac amyloidosis [11 with primary amyloidosis (AL) and 7 with senile systemic amyloidosis (SSA)]. Results AL patients (10/11) showed focally transmural vascular involvement by amyloid with thickening of the wall and impingement on the lumens. In SSA patients (6/7), the amyloid deposition was concentrated largely in the adventitia and external media. Histomorphometric analysis revealed that all patients with AL, SSA, and heart failure without amyloidosis had greater luminal areas than normal controls. In addition, the median of the ratio of subendocardial to subepicardial vascular luminal areas was 0.59 in AL patients, 1.17 in SSA patients, 0.94 in heart failure without amyloidosis patients, and 0.89 in normal controls ( P =.034). Conclusions This study shows that the degree of vascular involvement and wall thickening with subsequent impingement on the lumen is much greater in AL than in SSA. All patients with heart failure, with and without amyloidosis, displayed greater luminal areas than normal controls. Moreover, a twofold dilatation of the vessels in the subepicardium compared to those in the subendocardium was noted only in patients with AL. This may be due to transmural vascular involvement by amyloid in these patients, which concomitantly decreases the transmural ventricular perfusion pressure, leading to compensatory expansion of the subepicardial vessels.
Secondary structural analysis of retrovirus integrase: Characterization by circular dichroism and empirical prediction methods

The retrovirus integrase (IN) protein is essential for integration of viral DNA into host DNA. The secondary structure of the purified IN protein from avian myeloblastosis virus was investigated by both circular dichroism (CD) spectroscopy and five empirical prediction methods. The secondary structures determined from the resolving of CD spectra through a least-squares curve fitting procedure were compared with those predicted from four statistical methods, e.g., the Chou-Fasman, Garnier-Osguthorpe-Robson, Nishikawa-Ooi, and a JOINT scheme which combined all three of these methods, plus a pure a priori one, the Ptitsyn-Finkelstein method. Among all of the methods used, the Nishikawa-Ooi prediction gave the closest match in the composition of secondary structure to the CD result, although the other methods each correctly predicted one or more secondary structural group. Most of the alpha-helix and beta-sheet states predicted by the Ptitsyn-Finkelstein method were in accord with the Nishikawa-Ooi method. Secondary structural predictions by the Nishikawa-Ooi method were extended further to include IN proteins from four phylogenetic distinct retroviruses. The structural relationships between the four most conserved amino acid blocks of these IN proteins were compared using sequence homology and secondary structure predictions.
SU-E-T-220: A Web-Based Research System for Outcome Analysis of NSCLC Treated with SABR.

Purpose: To establish a web‐based software system, an electronic patient record (ePR), to consolidate and evaluate clinical data, dose delivery and treatment outcomes for non small cell lung cancer(NSCLC) patients treated with hypofractionated stereotactic ablative radiation therapy (SABR) across institutions. Methods: The new trend of information technology in medical imaging and informatics is towards the development of an electronic patient record (ePR), in which all health and medicalinformation of each patient are organized under the patient's name and identification number. The system has been developed using the Wamp Server, a package of Apache web server, PHP and MySQL database to facilitate patient data input and management, and evaluation of patient clinical data and dose delivery across institution using web technology. The data of each patient to be recorded in the database include pre‐treatment clinical data, treatment plan in DICOM‐RT format and follow‐up data. The pre‐treatment data include demographics data, pathology condition, cancer staging. The follow‐up data include the survival status, local tumor control condition and toxicity. The clinical data are entered to the system through the web page while the treatment plan data will be imported from the treatment planning system (TPS) using DICOM communication. Results: The collection of data of NSCLC patients treated with SABR stored in the ePR is always accessible and can be retrieved and processed in the future. The core of the ePR is the database which integrates all patient data in one location. Conclusions: The web‐based DICOM RT ePR system utilizes the current state‐of‐the‐art medicalinformatics approach to investigate the combination and consolidation of patient data and outcome results. This will allow clinically‐driven data mining for dose distributions and resulting treatment outcome in connection with biological modeling of the treatment parameters to quantify the efficacy of SABR in treatingNSCLC patients.
Performance of Carotid Ultrasound in Evaluating Candidates for Carotid Endarterectomy Is Optimized by an Approach Based on Clinical Outcome Rather Than Accuracy

Background and Purpose The best method of selecting endarterectomy candidates for cerebral angiography is controversial. Carotid duplex ultrasound (CDUS) is widely used, but its performance varies across institutions. The clinical utility of CDUS could be improved with test criteria based on patient outcome rather than test accuracy. Methods In 155 carotid bifurcations studied by CDUS and cerebral angiography, the degree of angiographic stenosis was measured by a reader, blinded to CDUS, using the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method. We calculated accuracy, sensitivity, and specificity for predicting ≥70% angiographic carotid stenosis of different peak systolic frequencies (PSF) measured by CDUS and generated a receiver operator characteristic (ROC) curve. We used NASCET outcome data and published data on angiographic complications to define relative “costs” of false-positive and false-negative CDUS, and we determined the point on the ROC curve representing the CDUS cri...
Glycogen Turnover in the Isolated Working Rat Heart

The isolated working rat heart was adapted for simultaneous determination of glycogen synthesis and degradation using a dual isotope technique. After prelabeling of glycogen with [U-14C]glucose, glycogenolysis was determined continuously from the washout of 14CO2plus [14C]lactate. Glycogen synthesis was determined during the same period from incorporation of [5-3H]glucose. In the absence of added hormones, hearts were predominantly glycogenolytic (1.5 μmol/min/g, dry weight), and there was simultaneous synthesis (11% of the rate of glycogenolysis). The percentage of glucose taken up by the heart that could traverse the glycogen pool as a consequence of glycogen turnover was minor (5%). Insulin (10 milliunits/ml) predictably stimulated glycogen synthesis (3.6-fold) and nearly abolished glycogenolysis. Addition of glucagon (1 μg/ml) increased contractile performance and initially stimulated glycogenolysis (3.8-fold) until glycogen was largely depleted. Net tritium incorporation was unaffected by glucagon. Both hormones stimulated glycolytic flux from exogenous glucose (3H2O from [5-3H]glucose) as well as total glycolytic flux (3H2O plus glycogenolysis). The initial stimulation in total glycolytic flux with glucagon was largely from glycogen, explaining the lag in stimulation from exogenous glucose. The relationship between the specific radioactivity and amount of glycogen remaining after different degrees of glycogenolysis suggests that the preference of glycogenolysis for newly synthesized glycogen is only partial.
The ecology and biosafety of baculoviruses.

Abstract Advances in the use of molecular techniques — particularly for virus identification, the investigation of latency and the infection process, plus the development of a theoretical framework containing a higher degree of biological realism — have pushed baculovirus ecology forward in the past few years. This has created a scenario in which many hitherto intractable questions about the behaviour of natural and genetically modified baculoviruses can now be addressed.
Catalysts for convenient aerobic alcohol oxidations in air: systematic ligand studies in Pd/pyridine systems

We report highly convenient Pd catalysts for the aerobic oxidation of alcohols, which are generated in situ by combining commercially available catalyst precursors. Systematic optimizations of the L- and X-type ligand environment and the employed additive allow the use of air as the sole oxidant without formation of Pd black. The resulting novel protocol provides quantitative yields of a broad variety of ketones and aldehydes.
Molecular biology of serotonin (5-HT) receptors

The recent cloning of three types of 5-hydroxytryptamine (5-HT, serotonin) receptors substantiates radioligand-based definitions of 5-HT receptors, and provides a framework in which to understand the function and evolution of the receptors. The primary sequences determined by molecular cloning of the 5-HT1c, 5-HT1a and 5-HT2 receptors place each of these 5-HT receptor subtypes into the class of G protein-coupled receptors. These receptors all share similar functional and structural features. Each receptor is positioned in the lipid bilayer with seven membrane-spanning domains and corresponding intracellular and extracellular domains. By analogy to the known functional structures of the beta-adrenergic receptor, the binding site of 5-HT is proposed to be in the membrane domains and the intracellular domain is important for G protein interaction. The primary sequences and the second messenger systems of the receptors indicate the 5-HT2 and 5-HT1c receptors are closely related, whereas the 5-HT1a receptor is more distantly related to the 5-HT2 and 5-HT1c receptors.
Synthesis of 5-styryl derivatives of uracil nucleosides and nucleotides.☆

Abstract Uracil nucleosides and nucleotides undergo a palladium catalyzed coupling reaction with styrenes to yield the respective 5-substituted derivatives.
Cancer and leukemia group B (CALGB) 89805: phase II chemoradiation trial using gemcitabine in patients with locoregional adenocarcinoma of the pancreas.

Purose. Determine the safety and efficacy of twice weekly gemcitabine and concurrent radiation to the upper abdomen followed by weekly gemcitabine in patients with surgically staged, locally advanced pancreatic cancer. Methods. Patients with surgically staged, locally advanced, nonmetastatic adenocarcinoma of the pancreas were treated with intravenous gemcitabine administered twice weekly (40 mg/m2/d) for 5 wk concurrent with upper abdominal radiation (50.4 Gy in 180 cGy daily fractions over 5.5 wk). At the completion of the chemoradiation, patients without disease progression were given gemcitabine (1000 mg/m2) weekly for five cycles. Each cycle consisted of 3 wk of treatment followed by 1 wk without treatment. Disease progression and response were assessed at 6- to 8-wk intervals. Results. From February through December 1999, 43 patients were entered into this phase II trial, 39 of whom were evaluable for treatment response. The median age was 59 yr (range: 39–84 yr); there were 18 males (47%) in the study. Grade III and IV hematologic toxicity occurred in 48 and 21% of patients, respectively, and was primarily leukocytopenia and neutropenia. Grade III and IV gastrointestinal toxicities occurred in 31 and 10% of patients, respectively. There was one death attributed to sepsis. The concurrent gemcitabine and radiation portion of the study was completed without treatment interruptions in 56% of patients. The overall median survival was 8.2 mo and the median survival in the 44% of patients demonstrating a sustained CA-19-9 response was 13.5 mo. Only six patients experienced local regional progression as their first site of failure. Two patients (5%) were still alive at 35 and 41 mo posttreatment. Conclusions. These results confirm the feasibility of twice weekly gemcitabine and radiation for the treatment of pancreatic cancer. Although this treatment strategy produced good local regional control, this did not result in a survival advantage. Stratifying patients by performance status and CA-19-9 response in future trials may be of value.
Menstrual cycle and dietary restraint influence taste preferences in young women

Previous reports indicate that some women increase their consumption of sugar and fat premenstrually. To ascertain whether this is due to differences in taste acuity for sweetness and fatness and/or preference across the menstrual cycle, 25 female and 12 male undergraduates rated the pleasantness, sweetness, and fatness of 16 taste stimuli made of dairy products with varied fat contents (0%, 3.5%, 10%, 36%) and sucrose (0%, 5%, 10%, 20%) over 4 consecutive weeks. There was a marked decline in ratings over the 4 weeks of testing. Taste preferences of women were not uniform across the menstrual cycle. Those who began testing during the luteal and menstrual weeks had increased preference ratings compared to those who began during the follicular or ovulatory weeks. Preference ratings for taste stimuli containing 0% and 5% sucrose were lower in women with higher scores on a restraint of eating scale, than for women with lower scores. No differences in sweetness or fatness ratings were observed across the menstrual cycle, or as a function of dietary restraint. Men had increased preference for taste stimuli containing 10% and 20% sucrose compared to women; however, no differences in ratings of either sweetness or fatness were found as a function of gender. These data indicate that taste preference in women is not homogeneous across the cycle. Instead, many factors, including the menstrual cycle and degree of eating restraint, influence preference ratings.
Techniques of evaluating long term oxide reliability at wafer level

This paper discusses techniques of evaluating long term oxide reliability at the wafer level. These techniques are presently used in the development of high reliability oxide processes. The first technique involves a statistical analysis of the electric field distribution of MOS capacitor primary breakdown. The second technique consists of monitoring time dependent breakdowns of test capacitors during a short four second voltage accelerated stress test. Using an empirically derived voltage acceleration factor (107/MV/cm) failure rates at nominal voltages can be accurately extrapolated from these voltage accelerated data. A discussion of how these techniques can be used to determine oxide reliability is presented.
Hegel's ‘picture-thinking’ as the interpretive logic of the popular

Religion as a mode of thinking, what Hegel calls ‘picture-thinking’ (Vorstellung), is the global logic of the popular. ‘Picture-thinking’, in both religion and the popular, is a mode of knowing that renders the immaterial and the abstract as sensuous, material, and concrete. The ‘guise’ of reality in ‘picture-thinking’, whether religious or popular, is an inverted reality and through its sensuous, particular, imagining, produces an inverted consciousness. The paper examines Hegel's concept of ‘picture-thinking’ and demonstrates how it has become the commonsense of contemporary popular culture through a close reading of women's romances as exemplary of a popular knowing that emphasizes the sensual concrete and cancels the abstract. The paper argues for a materialist reading of popular culture which undoes ‘picture-thinking’ and introduces the reader to the abstract social relations out of which ‘picture-thinking’ and other modes of concrete knowledge are constituted. Here the paper analyzes Marx's notion t...
Peer Victimization, Depressive Symptoms, and Rule-Breaking Behavior in Adolescence: The Moderating Role of Peer Social Support

The current study examined whether peer social support, alone or in conjunction with peer delinquency, moderated the relations between overt and relational victimization, depressive symptoms, and rule-breaking behavior. Participants included 152 adolescents (55% male; 95% Latino) between the ages of 14–19 and their second-hour teacher. Findings indicated that peer social support buffered the association between relational victimization and depressive symptoms. Overt victimization was uniquely related to increased rule-breaking behavior, but unrelated to depressive symptoms. Peer social support and peer delinquency interacted to influence the association between relational victimization and rule-breaking behavior. When levels of both social support and peer delinquency were high, relational victimization marginally significantly predicted increased rule-breaking behavior. Relational victimization was unrelated to rule-breaking behavior when levels of peer delinquency were high and social support were low. The moderating effects of peer social support did not differ according to gender. Implications of findings and directions for future research are discussed.
“The ‘Effects’ of infant day care reconsidered” reconsidered: Risks for parents, children, and researchers

Abstract In his article “The ‘Effects’ of Infant Day Care Reconsidered”, Belsky (1988) concludes that maternal employment puts infants at risk for developing emotional insecurity and social maladjustment. After a review of Belsky's and other research, this article offers a different conclusion. It is agreed that infants whose mothers work full-time during their first year are consistently and statistically significantly more likely than infants of mothers who work part-time or not at all to be classifed as insecurely attached when such infants are observed with their mothers in the Strange Situation. However, the difference is not large (8% greater probability), and it does not necessarily reflect emotional maladjustment. It is based on a single assessment procedure with a single partner, a procedure in which day-care infants may feel more comfortable than do other infants. Observations of heightened aggression in children who have been in day care as infants offer limited evidence of maladjustment as a consequence of maternal employment. But, there is no clear evidence that day care places infants at risk. Belsky suggests that observed day-care effects on attachment and aggression may be moderated by day-care quality; children's age, sex, and temperament; hours of separation from mother; overstimulation by mother; and congruence between the mother's attitude and work status. However, there is no convincing evidence that these factors are involved. The most promising factors to be used in accounting for individual differences in daycare infants' emotional development are the mother's attitude toward the infant, her emotional accessibility and behavioral sensitivity, and her desire for independence (her own and the infant's). What is needed now is research to assess and investigate such mediating factors, rather than blanket generalizations about day-care effects and implicit or explicit condemnations of maternal employment.
Clinical outcome of confluent laser photoablation for retinopathy of prematurity.

Abstract Purpose: During the past decade, laser photoablation has supplanted cryotherapy as the standard treatment for threshold retinopathy of prematurity (ROP). We evaluated the progression and the complication rate in a cohort of infants with threshold ROP treated with a confluent technique. Methods: We retrospectively studied 47 patients with ROP (91 eyes), treated with confluent diode laser photoablation. Four main outcomes were evaluated: (1) the rate of progression, (2) the frequency of laser retreatment, (3) postoperative complications, and (4) postoperative refractive error. Results: A mean of 1943 ± 912 laser burns were administered in a confluent pattern to 91 eyes with threshold ROP. Progression to stage 4 or 5 disease occurred in 13 of 29 eyes (44.8%) with zone I and posterior zone II and in 2 of 51 eyes (3.9%) with anterior zone II ROP (P = .01). Eyes with anterior zone II ROP that received more than or equal to 2000 burns progressed more than those that received fewer than 2000 burns. Only 1 eye (1%) needed a supplemental laser treatment. Postoperative complications included corneal edema (2.3%), anterior segment ischemia (2.3%), vitreous hemorrhage (7.9%), posterior synechiae (2.3%), cataract (4.9%), and macular ectopia (12%).The mean spherical equivalent at the last follow-up was −4.52 ± 5.63 D. Conclusions: In our series, infants received more laser burns than infants reported in the literature receiving scatter or near-confluent treatment. While confluent treatment almost eliminated supplemental treatment, it was associated with a similar rate of progression and complications as has been reported with other patterns of laser treatment. (J AAPOS 2002;6:81-5)
Motion-adaptive model-assisted compatible coding with spatiotemporal scalability

We introduce the concept of motion adaptive spatio-temporal model-assisted compatible (MA-STMAC) coding, a technique to selectively encode areas of different importance to the human eye in terms of space and time in moving images with the consideration of object motion. PRevious STMAC was proposed base don the fact that human 'eye contact' and 'lip synchronization' are very important in person-to-person communication. Several areas including the eyes and lips need different types of quality, since different areas have different perceptual significance to human observers. The approach provides a better rate-distortion tradeoff than conventional image coding techniques base don MPEG-1, MPEG- 2, H.261, as well as H.263. STMAC coding is applied on top of an encoder, taking full advantage of its core design. Model motion tracking in our previous STMAC approach was not automatic. The proposed MA-STMAC coding considers the motion of the human face within the STMAC concept using automatic area detection. Experimental results are given using ITU-T H.263, addressing very low bit-rate compression.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Potential role of UGT pharmacogenetics in cancer treatment and prevention: focus on tamoxifen and aromatase inhibitors

Tamoxifen (TAM) is a selective estrogen-receptor modulator that is widely used in the prevention and treatment of estrogen-receptor–positive breast cancer. Its use has significantly contributed to a decline in breast cancer mortality, since breast cancer patients treated with TAM for 5 years exhibit a 30–50% reduction in both the rate of disease recurrence after 10 years of patient follow-up and in the occurrence of contralateral breast cancer. However, in patients treated with TAM, there is substantial interindividual variability in the development of resistance to TAM therapy and in the incidence of TAM-induced adverse events, including deep-vein thrombosis, hot flashes, and the development of endometrial cancer. Aromatase inhibitors (AIs) have emerged as a viable alternative to TAM, working by inhibiting aromatase activity and blocking estrone/estrodiol biosynthesis in postmenopausal women. The current third-generation AIs, anastrozole, exemestane, and letrozole, were used initially for the treatment o...
Thermospheric temperatures and meridional winds measured at Albany, New York during geomagnetically disturbed periods

Abstract High quality optical data, obtained by using a high-resolution Fabry-Perot interferometer, were used to derive the thermospheric neutral temperatures and meridional wind velocities at a mid-latitude station, Albany (42.7°N, 73.8°W), New York, during the period 1978–1982. A total of 24 geomagnetically active nights, when the K p index was more than 3, were selected during the observation period. The neutral temperatures varied between about 900 and 1600 K, with a mean value of 1276 ± 54 K. Thermospheric temperatures were also estimated for these selected nights, using the 83 and 86 versions of the MSIS thermospheric model to compare with the experimental values. The experimentally determined temperature variations at the F -region heights were found to be in qualitative accord with the predicted variations based on the thermospheric models. However, the MSIS-83 model gave temperatures smaller than the measured values by about 250 K, while the difference was less than 200 K with the MSIS-86 estimates. In summary, the results of this study show a fair agreement between the observed temperature variations and the estimated variations using the MSIS models for geomagnetically active periods, and there is an increasing need to resolve the quantitative differences. The meridional wind velocities are generally equatorward and they increase from about 125 m s −1 shortly after sunset, to a maximum value of around 200 m s −1 before local midnight, and then decrease to less than about 100 m s −1 toward the early morning hours and become poleward by morning twilight. The mean meridional wind is essentially equatorward in agreement with the thermospheric circulation theory and also in general accord with other mid-latitude optical wind observations.
Understanding a studio environment: A complex system approach to a community of practice

This paper looks at characteristics of a studio environment and the ways in which engineering pedagogies can begin to incorporate them. Using inductive coding, student reflection forms, in which students described their experiences with a studio environment as they developed professional portfolios, are analyzed. Based on our findings and using communities of practice and complexity theory as a theoretical lens, we describe how portfolio studios engage students in key elements of learning. In particular, the analysis of students' reflection forms demonstrates that students validate each other's experiences through peer interaction, engage in the negotiation of meaning, and make sense of their own identity. The paper provides insights into studio environments and their role in engineering education, an explanation of our research methodology, the results, a discussion of the results and the ways in which they relate to communities of practice and complexity theory, and a conclusion focused on possible implications.
Antihormonal agents. Part 2: HPLC of ZK 98734 and its metabolites and ZK 98299

Procedures are described for the reverse phase HPLC analysis of the antihormonal steroid ZK 98734 and two of its metabolites. Conditions are developed for the HPLC of the pure drug substance and for following its pharmacokinetics and metabolism. Analysis conditions are also reported for the antiprogestin ZK 98299.
Serotonin involvement in a motor disorder of Scottish terrier dogs

Abstract The effect of altering the concentration of 5-HT or the catecholamines upon an inherited neurological condition of Scottish terrier dogs which is characterized by episodes of muscular hypertonicity was assessed in a blind study. Alpha-methyl-paratyrosine and imipramine did not modify the condition. Amphetamine sulfate induced episodes; however, the episode was generally of shorter duration than the behavioral effect. The severity of the clinical rating was markedly increased by p-CPA. This increased severity was reduced by 5-HTP administration. The peripheral serotonin antagonist xylamidine tosylate did not alter the severity of the disease. Nialamide and 5-HTP had a significant beneficial effect. The increase in severity of the disease which follows a decrease in 5-HT coupled with a decrease in severity with an increase in 5-HT suggest certain serotoninergic neurons are involved in modulation of skeletal muscle tone.
Caco-2 cell line: a system for studying intestinal iron transport across epithelial cell monolayers.

Abstract Iron transport across polarized intestinal epithelium was studied by using Caco-2 cells grown in bicameral chambers. When cells were grown under conditions of low, normal, or high iron concentration not only was the iron content of the cells markedly altered but the low iron cells exhibited a nearly 2-fold increase in transepithelial electrical resistance (TEER). 59Fe uptake from the apical surface into cells and transport into the basal chamber was affected both by the valency of the iron and the iron status of the cells, Uptake from 59Fe(II)-ascorbate was about 600 pmol 59Fe/h per mg protein, increased about 2-fold in low iron cells, and was about 13–200-fold greater than uptakes from 59Fe(III) chelated to nitrilotriacetic acid, BSA, or citrate. Transport into the basal chamber from59Fe(II)-ascorbate was 3.7 ± 1.7pmol/h per cm2 for Fe-deficient cells vs. 0.72 ± 0.1pmol/h per cm2 for normal-Fe cells and from 59Fe(III)-BSA 1.1 ± 0.2pmol/h per cm2 vs. 0.3 ± 0.03pmol/h per cm2 for deficient vs. normal iron cells, respectively. The greater transport of iron both from Fe(II) and in iron deficient cells supports the use of the Caco-2 cells as a model for iron transport.
Coarctation of the Aorta: Four Unusual Instances

Four unusual instances of coarctation of the aorta are presented. Three coarctations were located proximal to the left subclavian artery, and the other was in the normal location with a patent ductus arteriosus and an anomalous distal right subclavian artery. Unusual coarctations can be identified on physical examination on the basis of variations of blood pressure and pulses in the upper extremities. Unilateral rib notching may be noted on chest roentgenogram, and an aortogram can delineate its exact location. Four separate means of surgical repair are described.
Personality correlates of correctly identifying genuine suicide notes.

Lester (1991) showed that naive judges were reliable in their distinguishing genuine from simulated suicide notes. T o explore whether their success was associated with personality, 12 male and 17 female college students (Ma,, = 23.5 yr., SD=5.4) were asked to distinguish between 33 pairs of genuine and simulated suicide notes (Shneidman & Farberow, 1957) and also were given the 20 items of the Mach V measure of Machiavehanism (Christie, 1970) in a Likert-type format. The students correctly identified an average of 16.9 notes (SD=4.4) and received a mean Mach V score of -0.28 (SD= 10.42). The partial correlation coefficient between the number of genuine suicide notes identified correctly and the Mach V scores, controlling for age and sex, was -0.36 (two-tailed p<.10). Thus, Machiavelhan attitudes did not predict the students' success in identifying genuine suicide notes from simulated ones.
Technology Review: Toxic Responses in the Eye and Visual System

Toxic responses elicited by chemicals in the eye are quite different in many ways from those induced in other organs because of the uniqueness of the eye which is exposed to the outside environment and perfused extensively by a rich blood supply. As a result, the eye is highly vulnerable to local contacts of chemicals, toxins, pollutants and occupational hazards, and to toxic reactions of systemic agents. This article reviews the anatomy and physiology of the eye, ophthalmic toxicology research methods in vivo and in vitro, toxic responses induced by local agents and systemic drugs, and medical treatment of ocular toxic responses.
A reactive diffusion model describing transformation of bedrock to saprolite

Despite large ranges in rates of erosion and regolith production globally, much continental surface is regolith-mantled. This implies either that erosion rate is low relative to regolith formation over extensive regions, or that the rates of erosion and weathering advance (regolith formation) are in balance. Recent observations for many catchments that weathering-derived solute fluxes vary with the physical erosion rate of the catchment provide evidence that erosion and weathering advance rates may be balanced or at least coupled. Few theoretical models have been advanced to explain such observations, however, because weathering models generally consist of either fully parameterized reactive transport models that do not attempt to model geomorphological evolution, or geomorphologically parameterized models of landscape evolution that incorporate little geochemistry. Implementation of a full reactive transport code into a landscape evolution model is not currently tractable. We therefore present a reactive diffusion model that captures the essence of the chemical transformation of rock to saprolite for eventual incorporation into such models. Our model granite (albite+FeO-bearing phase+quartz) transforms to saprolite (goethite+ kaolinite+quartz). The FeO component transforms to goethite deeper than albite transforms to kaolinite. Between these two reaction fronts, porosity decreases relative to initial porosity. Without erosion, the depth of the weathering fronts vary as f ffiffi p and the weathering fluxes of aqueous Na or Si, which depend upon the porosity in the saprolite, decrease as 1ffiffi p . These results are in good agreement with the assumption of local chemical equilibrium. Analysis of the local equilibrium case for a further simplified two-mineral granite model shows that with constant erosion rate, the weathering rock is comprised of an unaltered-porosity (unoxidized Fe) zone, a reduced-porosity (partly oxidized Fe) zone, and a constant porosity (fully oxidized Fe) zone. This model documents three regimes: kinetic (weathering advance rate depends on reaction rate), transition (weathering advance rate depends on reaction and erosion rates), and local equilibrium (weathering advance rate depends only on erosion rate). The first and last of these have been previously called the weathering- and transportlimited regimes respectively. The time needed to reach steady state in the kinetic regime (70–3300yr) is comparable to geological estimates for weathering-limited landscapes. The analytical solutions document that diffusion-limited weathering advance rates in the presence of constant erosion can be consistent with constant weathering advance rates, thus providing a theoretical basis for coupling geochemical mineral reactions with erosion in landscape evolution models. © 2007 Elsevier B.V. All rights reserved.
Autoethnography of a First-Time Superintendent: Challenges to Leadership for Social Justice

This autoethnography elucidates the challenges I encountered in my efforts to maintain my commitment to leadership for social justice. When I assumed the superintendency of a small rural school district in southern Texas, I started collecting data in the form of a journal. My lived experiences, as recorded in my journal, were the sole source of data for this inquiry. This study provides a descriptive analysis of my daily experiences as a first-time superintendent. Due to time limitations, this project focuses only on the first year of my superintendency, giving particular attention to the political and social factors that impeded my philosophy of social justice.
Deficit in nitric oxide production in cirrhotic rat livers is located in the sinusoidal and postsinusoidal areas.

Intrahepatic nitric oxide (NO) production is decreased in cirrhotic livers. Our objective was to identify, in cirrhotic rat livers, intrahepatic vascular segments where the deficit of NO facilitate...