cssi/SciSciGPT-SciSciNet huggingface dataset:
Complexation of adamantane-ammonium substrates by beta-cyclodextrin and its O -methylated derivatives

A spectrophotometric method is used to determine formation constants of complexes ofβ-cyclodextrin, the 2,6-di-O-methylated and 2,3,6-tri-O-methylated derivatives ofβ-cyclodextrin as hosts with adamantan-1-ylammonium, adamantan-2-ylammonium and adamantan-1-ylmethylammonium as substrate species. The spectrophotometric method uses methyl orange anion and acid forms as indicator species. Complexes of the cyclodextrins with these species are determined as well as with the adamantane derivatives. Standard enthalpies and entropies of formation of all complexes are calculated from the temperature variation of the equilibrium constants.β-Cyclodextrin and its 2,6-O-methyl derivative have comparable complex strengths with adamantaneammonium substrates and these strengths are about two orders of magnitude stronger than the corresponding complexes of the permethylated derivative. Thermodynamic parameters are interpreted in terms of differing intramolecular properties of the cyclodextrin complexes.
Nursing Involvement in Prehospital Care

A tremendous impact can be made on prehospital care by Emergency Department nurses, and whether that impact is positive or negative depends on the groundwork that has been laid for the prehospital program. If the program is based on the team concept, with all members having the same goal to provide the highest level of patient care possible, then nursing can have a very positive impact. The key phrase is “include nursing,” in all aspects of the program planning and operation. If nurses are excluded, they can hardly be expected to be part of the team, when they haven't even been told the game plan. A survey of Emergency Department nurses from hospitals that range from University teaching facilities to small rural hospitals was conducted. The survey focused on two areas; the first dealt with the degree of nursing involvement in the prehospital program, and the second addressed nurses' attitudes toward the program.
Adjuvant Hormonal Therapy Use Among Women with Ductal Carcinoma In Situ

Abstract Objective: In the absence of consistent guidelines for the use of adjuvant hormonal therapy (HT) in treating ductal carcinoma in situ (DCIS), our purpose was to explore a variety of factors associated with discussion, use, and discontinuation of this therapy for DCIS, including patient, tumor, and treatment-related characteristics and physician-patient communication factors. Methods: We identified women from eight California Cancer Registry regions diagnosed with DCIS from 2002 through 2005, aged ≥18 years, of Latina or non-Latina white race/ethnicity. A total of 744 women were interviewed an average of 24 months postdiagnosis about whether they had (1) discussed with a physician, (2) used, and (3) discontinued adjuvant HT. Results: Although 83% of women discussed adjuvant HT with a physician, 47% used adjuvant HT, and 23% of users reported discontinuation by a median of 11 months. In multivariable adjusted analyses, Latina Spanish speakers were less likely than white women to discuss therapy (od...
The VHL/HIF oxygen-sensing pathway and its relevance to kidney disease

Over the past decade major advances have been made in our understanding of the molecular machinery that mammalian cells use to sense and to adapt to a low-oxygen environment. A critical mediator of cellular adaptation to hypoxia is hypoxia-inducible factor (HIF), a basic helix-loop-helix transcription factor that consists of an oxygen-sensitive α -subunit, HIF- α and a constitutively expressed β -subunit, HIF- β . Under conditions of normal oxygen tension, the HIF- α subunit is hydroxylated by specific prolyl-hydroxylases and targeted for rapid proteasomal degradation by the von Hippel–Lindau (VHL) tumor suppressor, which is the substrate recognition component of an E3-ubiquitin ligase. In a hypoxic environment or in the absence of functional VHL tumor suppressor protein irrespective of oxygen concentration, HIF- α is not degraded and translocates to the nucleus, where it dimerizes with HIF- β to form transcriptionally active HIF. As a transcription factor, HIF is involved in the regulation of many biological processes that facilitate both oxygen delivery and adaptation to oxygen deprivation by regulating genes that are involved in glucose uptake and energy metabolism, angiogenesis, erythropoiesis, cell proliferation and apoptosis, cell–cell and cell–matrix interactions, and barrier function. This review summarizes some of the most recent advances in the VHL/HIF field and discusses their relevance for pathogenesis and treatment of acute ischemic renal failure, renal fibrosis, and renal cancer.
The influence of polymers on the hydration of portland cement phases analyzed by soft x-ray transmission microscopy

Abstract The soft X-ray transmission microscope, which allows the in situ observation of wet samples of cement at normal pressures with high spatial resolutions (25 nm), was used to observe and compare the effects of two polymers — a water soluble polymer (HPMC — hydroxypropyl methylcellulose) and a latex [EVA-poly(ethylene- co -vinyl acetate)] on the early hydration of C 3 S and C 3 A. These polymers are used to modify the properties of fresh and hardened mortars and concretes, especially when adhesive characteristics are required. The images show that the cellulose ether delays the hydration of the cementitious particles and promotes the formation of inner products rather than outer products. On the other hand, EVA particles agglomerate around the hydrating C 3 S grains, and act as nucleation agents in the development of the composite microstructure. While HPMC slightly changed the aspect of C 3 A hydration, EVA inhibited or even prevented the formation of ettringite crystals during the early stage of hydration, and resulted in a cloud of small, bright particles concentrated around the hydrating C 3 A grains.
Ηepatitis A and enteric fever in Greece, 2004–2011: A cross-sectional analysis

Summary Background In Greece the number of international travellers has increased significantly the past decade. Aim To study the impact of international travels on the epidemiology of hepatitis A and enteric fever in Greece. Methods We studied cases of hepatitis A and enteric fever notified through the National Surveillance System from January 1, 2004 through December 31, 2011. Results A total of 921 cases of hepatitis A and 106 cases of enteric fever were notified; of them, 88 (9.5%) and 46 (43.4%) were travel-associated, respectively. Travellers returning from Eastern Europe and the Middle East accounted for most imported cases of hepatitis A (37 (43.5%) and 14 (16.5%) cases, respectively). The Indian subcontinent was the prevalent area of acquisition of travel-associated enteric fever, followed by the Middle East (35 (83.3%) and 4 (9.5%) cases, respectively). Foreign-born travellers accounted for 43 (48.8%) and 39 (86.6%) cases of travel-associated hepatitis A and enteric fever, respectively. Children Conclusions International travels have a significant impact on the epidemiology of enteric fever in Greece, affecting mainly foreign travellers. Hepatitis A carries a significant burden of morbidity among Greek travellers and children of foreign nationality. There is a need to improve travel medicine services for travellers travelling to developing countries.
A single amino acid substitution in a cytochrome c T cell stimulatory peptide changes the MHC restriction element from one isotype (I-Ak) to another (I-Ek)

The binding sites of class II major histocompatibility complex (MHC) molecules can accommodate many seemingly diverse peptides. In the case of mouse class II molecules, it appears that in general, the I-A and I-E isotypes associate with different peptides. In this study we report an example where a single amino acid substitution in an I-Ak restricted peptide changes the restriction element to I-Ek. A T cell hybridoma, F6.A10, specific for the peptide 93–104 from mouse testicular cytochrome c (Mt cyt 93–104) was found to be restricted by I-Ak using class II molecule specific blocking monoclonal antibodies (mAb). The activation of this hybridoma by Mt cyt 93–104 was competitively inhibited by other peptides that bind to the I-Ak molecule but not by the peptide Mt cyt 93–104(A96) in which lysine at position 96 was substituted by alanine. This single amino acid substitution resulted in the ability of Mt cyt 93–104(A96) to activate the pigeon cytochrome c specific, I-Ek restricted, T cell hybridoma 2B4.11. The activation of 2B4.11 by Mt cyt 93–104(A96) was inhibited by peptides which bind to the I-Ek molecule but not by Mt cyt 93–104 and by mAb specific for I-Ek but not by mAb specific for I-Ak. These results suggest that the amino acid at position 96 may be an important anchor residue for both I-Ak and I-Ek binding but that peptides with different amino acid side chains are accommodated at that position by one or the other MHC class II isotype. Thus, in this particular case a single amino acid residue in the peptides determines the MHC class II isotype specificity.
FURTHER STUDIES OF THE ELECTROCARDIOGRAPHIC EFFECTS OF EXPERIMENTAL MYOCARDIAL LESIONS.

Abstract The electrocardiographic effects of 25 chemically produced myocardial lesions in dogs were studied. Eleven of these were restricted to the subepicardial half of the left ventricular wall, 2 were located in the posterior basal portion of the left ventricle, and 12 were located in the right ventricular wall. Eight of the 11 subepicardial left ventricular lesions altered only mid-temporal and terminal portions of the QRS complex. The other 3 lesions were all located near the interventricular septum and altered early as well as later portions of the QRS. The 2 lesions of the posterior basal left ventricular wall altered only mid-temporal and terminal portions of the QRS complex. Right ventricular lesions in the right lateral wall near the base and those near the interventricular septum altered early as well as late portions of the QRS complex. Other right ventricular lesions altered only mid-temporal and terminal portions of the QRS. The significance of these findings may be summarized as follows: (1) Lesions in a variety of locations cannot be recognized by electrocardiographic standards which require abnormalities of the initial portion of the QRS complex. (2) Recognition of the relatively small and variable electrocardiographic effects of subepicardial, posterior basal, and right ventricular lesions may require modification of current clinical electrocardiographic techniques and standards for the diagnosis of myocardial infarction (3) The finding that most subepicardial lesions did not alter initial portions of the QRS is not consistent with reported evidence that activation of only subepicardial portions of the heart contributes to the form of QRS deflections.
Effects of injected atomic coherence on single-mode frequency locking in a cavity.

The coupling of an electric field to an atomic beam prepared in a phase-locked coherent superposition of energy eigenstates is examined for a ring-laser cavity. The active medium is assumed to be a collection of noninteracting homogeneously broadened two-level atoms whose transition is electric-dipole allowed. The atom-field interaction is treated semiclassically and the atomic coherence injected into the cavity is assumed to be phase matched to the unidirectional plane-wave cavity mode. The polarization is derived for the case in which the electric-field-mode envelope has at most linear phase variations in time and is applied to the problem of frequency locking in a cavity. The presence of the atomic coherence causes the active medium to possess an inherent polarization, i.e., a field-independent contribution. This enables an optical cavity to support laser oscillation over the entire range of relative excitations, in particular, even for strongly absorbing media. A simple linear stability analysis is performed on the electric-field envelope by describing the medium with a slowly varying polarization valid when the time scales of the atomic response are much smaller than those of the variations in the envelope. The stability of frequency-locked oscillation depends on the detuning of the cavity from line center and the strength of the injected coherence relative to that of the injected population difference.
Formation of Hydride, Formyl, Hydroxymethyl, Dimetal Ketone, and Ethylene-Bridged Species from Small-Molecule Substrate Reactions with Rhodium Complexes of an N4 Nonmacrocyclic Ligand

Reactions of the rhodium(II) dimer [(dbpb)Rh]2 (1) ((dbpb)H2 (2) = 4,5-dimethyl-1,2-bis((4-(1-butylpentyl))pyridine-2-carboxamido)benzene) with H2, CO, and CH2CH2 produce a rhodium(III) hydride, (d...
Standardization of Reactor Ratings

THE STANDARDIZATION of reactor ratings will allow the physical properties and electrical characteristics of reactors to be standardized into classes of preferred ratings. Industry-wide acceptance of the preferred ratings should eventually result in reduced costs, shorter delivery time, and better use of materials as tests and service on the same size of reactor will point to improvements. The use of large steps between preferred ratings will hasten the realization of these benefits.
Functional principal component model for high-dimensional brain imaging

We explore a connection between the singular value decomposition (SVD) and functional principal component analysis (FPCA) models in high-dimensional brain imaging applications. We formally link right singular vectors to principal scores of FPCA. This, combined with the fact that left singular vectors estimate principal components, allows us to deploy the numerical efficiency of SVD to fully estimate the components of FPCA, even for extremely high-dimensional functional objects, such as brain images. As an example, a FPCA model is fit to high-resolution morphometric (RAVENS) images. The main directions of morphometric variation in brain volumes are identified and discussed.
Live interest meter: learning from quantified feedback in mass lectures

There is currently little or no support for speakers to learn by reflection when addressing a big audience, like mass lectures, virtual courses or conferences. Reliable feedback from the audience could improve personal skills and work performance. To address this shortcoming we have developed the Live Interest Meter App (LIM App) that supports the gathering, aggregation and visualization of feedback. This application allows audience members to easily provide and quantify their feedback through a simple meter. We conducted several experimental tests to investigate the acceptance and perceived usefulness of the LIM App and a user study in an academic setting to inform its further development. The results of the study illustriate the potential of the LIM App to be used in such scenarios. Main findings show the need for motivating students to use the application, the readiness of presenters to learn retrospectively, and distraction as the main concern of end users.
Large deviations results for the exit problem with characteristic boundary

Abstract We consider the exit problem for an asymptotically small random perturbation of a stable dynamical system in a region D. We show the standard large deviations results for the exit distribution and mean exit time, as obtained by Wentzell and Freidlin under the assumption of nontangential drift 〈b, n〉
Barium titanate/noble metal laminates prepared by the oxidation of solid metallic precursors

A novel and attractive method for preparing multicomponent electronic ceramics and ceramic-metal composites is the oxidation of solid metallic precursors (SMP). This metallurgical processing route consists of the following steps: (i) preparation of a solid metallic precursor containing the proper ratio of elements for the final ceramic or ceramic-metal composite, (ii) compaction and forming of the metallic precursor into a desired shape, and (iii) oxidation to produce a monolithic ceramic or ceramic-metal composite. While the SMP method has been used to prepare wires and tapes containing a variety of superconducting oxides, this method has not been widely used to synthesize other electronic ceramics. In this paper, the synthesis of dielectric BaTiO3/noble metal laminates from solid metallic precursors is discussed. Ba–Ti precursor powders have been produced by solid-state mechanical alloying. The precursor powder was sealed inside noble metal tubes and rolled to form thin Ba–Ti/noble metal laminates. Exposure of the Ba–Ti core in such tapes to temperatures ≥ 300 °C in pure oxygen resulted in rapid oxidation. Post-oxidation annealing at elevated temperatures (≥900 °C) yielded dielectric BaTiO3/Ag or BaTiO3/Pd laminates.
Polarization at the gold/pentacene interface

Abstract Direct and inverse photoemission spectroscopy are used to investigate the electronic polarization P = P+ + P− induced by the pentacene anion and cation at the Au/pentacene interface. Based on the spectroscopic measurements and on previously published calculations, we determine that the total polarization at the metal interface is approximately 0.67 eV larger than at the surface of the pentacene film, leading to a corresponding decrease of the interface transport gap. This reduced interface gap leads to hole and electron injection barriers of 0.47 eV and 1.17 eV, respectively.
Tracing teacher and student learning in teacher‐authored narratives

Abstract Using a Vygotskian sociocultural view of learning, this article explores what teacher‐authored narratives can tell us about the internal activity of teacher learning, how teacher learning works to alter the nature of activity in the classroom, and how that, in turn, influences how teachers describe the nature of student learning. By examining how a teacher narrates the experience of creating and co‐teaching a literature course for immigrant high school students in a New York City public school, we see how she comes to understand and enact new ways of participating in the social practices associated with the teaching of literature. As this teacher and her students began to internalize these new modes of engagement and the values they represent they also began to reconceptualize how they think about and engage in the teaching and reading of literature.
Structural analysis of liquid methane—water and liquid methane—methanol gels

Abstract Liquefied natural gas has been gelled by the addition of colloidal lyophobic particles of CH3OH and H2O. These solid particles were formed by a vapor condensation technique utilizing homogeneous nucleation and particle growth, and the thermodynamic conditions were such that crystalline clathrate particles may have formed. To study this possibility, X-ray diffraction, microscopic observation, and composition analyses were performed, and the results supported this clathrate hypothesis. The attractive interactions for such particles were then analyzed theoretically. The predicted van der Waals force was sufficiently low to suggest that hydrogen bonding of surface hydroxyls and possibly cage bridging produced the observed gel structure.
Structure-function relations for ferredoxin reductase

Ferredoxin: NADP+ reductase is representative of a large family of flavoenzymes which catalyze the interchange of reducing equivalents between one-electron carriers and the two-electron-carrying nicotinamide dinucleotides. The structure of the enzyme from spinach is known at 1.7 A resolution and this structure, together with results of chemical modification and site-directed mutagenesis studies, gives insights into features of the structure that are important for function.
Carcinoma of the bladder: treatment by radical cystectomy.

Abstract Proper timing for radical cystectomy remains a dilemma. To resolve the problem, a series of 141 consecutive patients who underwent simple or radical cystectomy between 1955 and 1971 were studied. Symptoms, interval before diagnosis, and stage and grade of lesion were analyzed and correlated with survival. Although stage and grade are the most important determinants for a radical procedure, other factors merit close attention. Previous studies have demonstrated decreased survival with invasion through more than one half of the bladder muscle. The present study, in contrast, reveals a significant decrease in survival with any evidence of muscle invasion. Dysuria or duration of symptoms for longer than 6 months was uniformly associated with decreased survival rates. Preoperative radiotherapy caused marked improvement in stage of tumors, with subsequent improved survival. Improved operative techniques and preoperative and postoperative care have led to a progressively decreased mortality from 8% overall to 2% in the most recent 50 cystectomies. Since neither operative morbidity nor mortality was altered by the addition of pelvic lymphadenectomy, a more aggressive attitude toward radical management is recommended.
Soil nutrient leaching in response to simulated acid rain treatment

Soil and soil solution nutrient concentrations were evaluated over a 30-mo period to determine the impact of simulated acidic precipitation (70:30 equivalent basis H2SO4: HNO3) at pH values of 5.7, 4.5, 4.0, and 3.5 on forest. microcosms. Soil nutrient analysis indicated significantly lower concentrations of exchangeable Ca and Mg in the top 3.5 cm of the mineral soil after 30 mo of pH 3.5 treatment. Leachate collected from the pH 4.5, 4.0, and 3.5 treatments at the 25 cm depth (below the A.: horizon) exhibited significant increases in Cl, NH4, PO4, K, and SO4 concentrations compared to the pH 5.7 treatment. At the 50 cm depth (mid-profile) all leachate element concentrations except NH4 increased significantly in response to treatment. At the 100 cm depth (profile bottom), no significant effects of treatment on leachate chemistry were observed. The elevated base cation concentration values found in the 50 cm soil solution samples support at least partially the described reduction in Ca and Mg in the surface soil horizon. The 100 cm concentration data indicate that cations mobilized out of the A.: and upper B horizon in response to treatment were immobilized before reaching the bottom of the soil profile. Evaluation of nutrient flux out of the microcosm at the 100 cm depth did not indicate any statistically significant response to the treatment. Nitrate rather than SO4 was found to be the dominant anion leaving the microcosm by an average factor of ∼7 to 1.
The cannabis withdrawal syndrome.

Purpose of reviewThe demand for treatment for cannabis dependence has grown dramatically. The majority of the people who enter the treatment have difficulty in achieving and maintaining abstinence from cannabis. Understanding the impact of cannabis withdrawal syndrome on quit attempts is of obvious
Thermal Degradation of Poly(vinylbutyral)/Ceramic Composites: A Kinetic Approach

Kinetic models for the thermal degradation of poly(vinylbutyral) PVB/Al2O3 and PVB/AlN composites, based on weight loss and evolved gas analysis (EGA), are presented. TG (sample weight loss) and FT-IR (mixture gas spectra) data were measured to elucidate the kinetic models using isothermal and nonisothermal approaches. The mixture IR spectra at each time or temperature were resolved using a least-mean-square (LMS) algorithm to obtain the dynamic information for each major volatile product formed during the degradation process. The kinetic results using isothermal and nonisothermal approaches showed excellent agreement. Activation energies of PVB thermal degradation are ∼300 kJ/mol in nitrogen and ∼200 kJ/mol in air for pure PVB and ∼100 kJ/mol for PVB/Al2O3 and PVB/AlN in nitrogen. The polymer residues at different isothermal treatments were subjected to DRIFTS spectra, and the carbon content of the residual samples was analyzed using a Leco analyzer.
Assessment of Obesity and Cardiovascular Risk in South Asians

In 2010, coronary disease was officially recognized as the number one cause of death in India. However, it has long been known that the prevalence of cardiovascular disease in South Asians is significantly higher than in other ethnic groups. More than 60 % of the world’s coronary disease burden resides in South Asia, and the first coronary event occurs, on average, over 10 years earlier in South Asians than in other ethnicities. This higher coronary event rate is attributed to both the earlier onset and high incidence of several coronary risk factors, such as obesity/metabolic syndrome, dyslipidemia, and insulin resistance/diabetes, coupled with a sedentary lifestyle. Despite the abundance of traditional risk factors, South Asian cardiovascular mortality is grossly underestimated by traditional risk factor modeling (e.g., Framingham, QRISK, Reynolds, etc.). Nontraditional risk factors, which include more advanced lipid and inflammatory biomarkers, adjusted body mass index (BMI) cutoffs, and even progenitor cell assessment, are independently predictive of risk in the South Asian population and may provide enhanced risk assessment beyond traditional models. This review details the magnitude of the coronary disease burden in the South Asian population, the traditional risk factors that may drive this South Asian epidemic, the limitations of these same traditional risk factors in assessing this risk, and the potential of novel inflammatory and lipid biomarkers to better capture this risk in the South Asian population.
The aortopathy of bicuspid aortic valve disease has distinctive patterns and usually involves the transverse aortic arch.

Objectives Bicuspid aortic valves are associated with a poorly characterized connective tissue disorder that predisposes to aortic catastrophes. Because no criterion exists dictating the appropriate extent of aortic resection in aneurysmal disease of the bicuspid aortic valve, we studied the patterns of aortic dilation in this population. Methods Sixty-four patients with bicuspid aortic valves who underwent computed tomographic or magnetic resonance angiography and echocardiography were retrospectively identified between January 2002 and March 2006. Orthonormal 2–dimensional or 3-dimensional aortic diameters were measured at 10 levels. Agglomerative hierarchic clustering with centered correlation distance measurements and complete linkage analysis was used to detect distinct patterns of aortic dilatation. Results Mean aortic diameter was 28.1 ± 0.7 mm at the annulus and 21.7 ± 0.4 mm at the diaphragmatic hiatus. The aorta was largest in the tubular ascending aorta (45.9 ± 1.0 mm). Compared with the descending aorta, the transverse aortic arch was also dilated ( P Conclusion Distinct patterns of aortic dilatation in patients with bicuspid aortic valves call for an individualized degree of aortic replacement to minimize late aortic complications and reoperation. Patients in clusters III and IV should have transverse arch replacement (plus concomitant root replacement in cluster IV). Patients in cluster I should undergo complete aortic root replacement, whereas in patients in cluster II supracommissural ascending aortic grafting is adequate.
Peak exposure concentrations of dust and flour aeroallergen in flour mills and bakeries

As part of an epidemiological study amongst workers exposed to flour we measured peak exposure levels to total dust and flour aeroallergen with personal samplers in bakeries, flour mills and packing stations. Short-term tasks which were expected to give rise to high concentrations of exposure (peaks) were identified. The frequency and duration of these tasks were estimated and their levels of exposure to dust and flour aeroallergen measured. In total 209 samples were taken. The highest exposure concentrations both for dust (geometric mean > 30 mg m-3) and for flour aeroallergen (geometric mean > 500 micrograms m-3) were measured during certain operations. Exposure concentrations for the tasks were often much higher than the levels we had measured over a shift in a previous study. This might be important for sensitization and for the development of asthma. Peak exposure concentrations could be used to explore the exposure-response relationship more comprehensively. In general average flour aeroallergen concentrations increased linearly with average dust concentrations, although there were some exceptions.
PCS 1900 MHz duplexer using thin film bulk acoustic resonators (FBARs)

An ultra-miniature duplexer (5 × 8 × 2.2 mm3) consisting of two FBAR filters and nine passive components operating at 1900 MHz is described. The minimum insertion loss for the Tx and Rx bands is better than –3 dB. Isolation between the Tx and Rx ports exceeds 50 dB over most of the Tx band and 46 dB in the Rx band. The FBAR filters handle up to 2 W throughout the passband.
Effective strategy of the overwintering of semiaquatic bugs: overwintering of Velia caprai (Heteroptera: Gerromorpha: Veliidae)

Overwintering of Velia caprai was studied during the winter months 2006–2007 in the area of South Bohemia (Czech Republic) by (1) field phenological observations and samples, (2) study of artificially established experimental cohorts in an unheated glasshouse, and (3) auxiliary experiments in a laboratory. Velia caprai has a unique way of overwintering within the gerromorphan bugs that is rare among insects generally; it can overwinter in both an adult and an egg stage. Most females reach sexual maturity before overwintering, mate with mature males, overwinter actively on the water surface and lay eggs during the winter. The dormant eggs can be induced to hatch by increasing temperatures. Winter oviposition can be interpreted as a sign of a risk‐spreading reproductive strategy. The overwintering of both adults and eggs provides a chance to adapt to changes in the local environmental conditions and could be an important determinant in broad variability of life‐history traits.
Teaching Basic Electrophysiology with the Aid of a Computer Program

Objective: Understanding the basis of electrophysiology is essential to the formation of a student of biological sciences. A solid base on the fundamental concepts paves the way for a better comprehension of more complex phenomena. We implemented a computer program (LabAXON) that simulates the electrical activity of an axon in a user friendly format. This program helps the student to understand the generation of the action potential and the effects of extracellular ionic concentration and stimuli waveform.Methods: This program was based on the classical Hodgkin and Huxley formalism. LabAXON allows the students to reproduce the basic experiment these Nobel prize-winning scientists performed on the squid giant axon. Important concepts such as Cronaxia curve, Current-Voltage relationship and Ion Reversal Potential can be explored in an interactive way. A user-friendly interface permits a rapid change of parameters and the ability to see the effects on-line. Also we created a workbook with a list of exercises that covers the essential points of the lecture.Conclusions: The processes that take place at the membrane set the stage for several concepts that will come out in the following years of the student's education: how drugs interact with channels, effect of ionic imbalance, refractoriness of the membrane, to name a few. Computer simulations help to reinforce those topics in the student in a self paced manner. It constitutes an excellent aid for the medical educator. LabAXON and the companion workbook are freely available on our departmental website.
Geochronology of the Mesoproterozoic State Farm gneiss and associated Neoproterozoic granitoids, Goochland terrane, Virginia

The Goochland terrane is an isolated block of Mesoproterozoic crust in the Piedmont Province of central Virginia. We report U-Pb zircon dates and whole-rock major and trace element data for the State Farm gneiss, one of the main units in the terrane, and additional results for a newly recognized suite of Neoproterozoic granitoids that intrude the gneiss. The State Farm gneiss ranges in bulk composition from quartz monzodiorite to granite, and three samples yield U-Pb zircon dates of 1046 +7/–6 Ma, 1039 +18/–11 Ma, and 1023 ± 10 Ma. We interpret these dates as igneous crystallization ages, which indicate a maximum emplacement interval of ca. 1057–1013 Ma for these samples. Neoproterozoic granitoids (including the Fine Creek Mills and Flat Rock granites) are more alkaline than the State Farm gneiss and display all compositional characteristics of A-type granites (e.g., high Fe/Mg, Ga, Ga/Al, Nb, Zn, Y, Zr). U-Pb zircon analyses from five separate bodies indicate crystallization ages from ca. 654 to 588 Ma, but all results are complicated by Mesoproterozoic (ca. 1 Ga) inheritance, coupled, in some cases, with secondary Pb loss. We interpret the ages and compositions of the younger rocks to reflect Neoproterozoic rifting of the Goochland terrane, but its location during rifting is uncertain. The terrane may have been separated from Laurentia during the Neoproterozoic breakup of Rodinia and later reattached.
Enhancing coping behaviors in at-risk populations: The effects of time-management instruction and social support in women from dual-earner families.

The differential effects of time-management training and social support on modification of stress-producing behaviors were evaluated in fifty-six women from dual-earner families. Women were randomly assigned to either time management plus group support, time management only, group support only, or a delayed-treatment control condition. Women receiving time-management instruction reported significant increases in targeted stress-reducing activities relative to those in the support only or delayed-treatment control conditions. Findings were maintained at three-month follow-up and replicated with the delayed-treatment control group. Changes in knowledge and self-efficacy mirrored changes in reported activities. Implications concerning time-management training and the role of social support for this type of at-risk population are discussed.
Characterization of surface oxides by Raman spectroscopy

Raman backscattering spectroscopy is used to characterize thin non-metallic films for applications in materials research. In situ studies of the oxidation and hot salt corrosion of iron- and nickel-based alloys demonstrate the capability of obtaining structural and chemical information from surface films on samples at elevated temperatures (up to 850°C). Studies of the oxidation of SAE 310 stainless steel and similar alloys show that phases of iron, chromium and mixed spinel oxides are identifiable in surface films which are too thin for analysis by X-ray diffractometry. This information is obtained both during and after exposure to high temperature environments. Similar data are obtained from alloys undergoing corrosive attack by a surface coating of molten salt. Both salt chemistry and oxide formation are simultaneously monitored using the Raman technique.
Toll-like receptor 2 expression on human conjunctival epithelial cells: a pathway for Staphylococcus aureus involvement in chronic ocular proinflammatory responses.

Background Staphylococcus aureus colonization is common in atopic keratoconjunctivitis, potentially activating epithelial cells via toll-like receptor 2 (TLR-2) and the receptor for platelet-activating factor (PAFR). Objectives To examine human conjunctival epithelial cells for the expression of TLR-2 in vitro and in vivo and to evaluate the role of TLR-2 in S aureus -mediated activation of these cells. Methods Conjunctival epithelial cells isolated from cadaveric tissues were stimulated with interferon γ (IFN-γ) or a commercial S aureus cell wall extract ( Staphylococcus aureus -CWE) (with or without anti-TLR-2 blocking antibody or PAFR antagonist) and were analyzed for tumor necrosis factor α (TNF-α) and interleukin 8 (IL-8) release; surface expression of TLR-2, intercellular adhesion molecule-1, HLA, and CD14; and TLR-2 messenger RNA expression. Ocular surface cells collected via impression cytology were examined for TLR-2 expression via flow cytometry. Results Expression of TLR-2 was up-regulated on conjunctival epithelial cells by IFN-γ and Staphylococcus aureus -CWE. Expression of TLR-2 messenger RNA was increased by IFN-γ. Staphylococcus aureus -CWE up-regulated intercellular adhesion molecule 1, HLA, and CD14 expression and increased TNF-α and IL-8 release in a dose-dependent manner. Anti-TLR-2 significantly inhibited TNF-α release, whereas PAFR antagonist significantly inhibited IL-8 release. Toll-like receptor 2 was expressed on conjunctival epithelial cells from 4 of 5 patients with atopic keratoconjunctivitis, 3 of 5 with seasonal allergies, and 0 of 3 without allergies. Conclusions Conjunctival epithelial cells express TLR-2 and may play an active role in the chronic ocular inflammatory response to S aureus through pathways that involve TLR-2 and PAFR.
Three‐step growth method for high quality AlN epilayers

We report a three-step growth method to grow thick and high quality aluminum nitride (AlN) epilayers on sapphire substrates by metal organic chemical vapor deposition (MOCVD). The three-step growth method begins with a deposition of a thin AlN buffer layer at 950 °C followed by an intermediate AlN (I-AlN) layer at 1100 °C, and finally a thick AlN epilayer at high temperature around 1325 °C. AlN epilayers grown by this method have smooth surfaces, narrow width of X-ray rocking curves, and strong band edge photoluminescence (PL) emissions with low impurity emissions. Transmission electron microscopy revealed that most of the threading dislocations are annihilated within 300 nm. Stacking faults are greatly reduced in epilayers grown by this method resulting in very low screw type threading dislocation density. Dominant threading dislocations in the AlN epilayers are edge type originated from misfit dislocations (MD).
Seven Decades of East African Miocene Anthropoid Studies

s of the International Symposium Evolution of Middle-to-Late Miocene Hominoids in Africa, July 11-13, 1999, H. Ishida, ed., Takaragaike, Kyoto, Japan. Simons, E.L., 1963, Some fallacies in the study of hominid phylogeny, Science. 141: 879-889. —— 1969, Late Miocene hominid from Fort Ternan, Kenya, Nature. 221: 448-451. Simons, E.L., and Fleagle, J.G., 1973, The history of extinct gibbon-like primates, in: Gibbon and Siamang,vol. 2, D.M. Rumbaugh, ed., Karger, Basel, pp.121-148. Simons, E.L., and Pilbeam, D.R., 1965, Preliminary revision of the Dryopithecinae (Pongidae, Anthropoidea), Folia Primatologica. 3: 81-152. Walker, A., 1969, Lower Miocene fossils from Mount Elgon, Uganda, Nature. 223: 591-593. —— 1992, Louis Leakey, John Napier and the history of Proconsul, Journal of Human Evolution. 22: 245254. Walker, A.C., and Pickford, M., 1983, New postcranial fossils of Proconsul africanus and Proconsul nyanzae, in: New Interpretations of Ape and Human Ancestry, R.L. Ciochon and R.S. Corruccini, eds., Plenum, New York, pp. 325-351. Walker, A.C., and Rose, M.D., 1968, Fossil hominoid vertebra from the Miocene of Uganda, Nature. 217: 980-
Letters to Sarah: analysis of email responses to an online editorial

An editorial opposing the violence being perpetrated on the Palestinians by the Israeli government that was written on the Common Dreams website prompted several hundred email responses to the author. The essay had been reposted to many listservs and other websites around the world. In a case study approach, we track the repostings and qualitatively and quantitatively analyze the responses to that editorial, to determine the nature of the discourse in an electronic environment. The study found that readers of the essay were prompted to write to the author largely when they agreed with her position because of their political or religious views, linked to their own experience or feelings, wished to relate their own personal stories, and when they were male.
Escherichia coli Thioredoxin-like Protein YbbN Contains an Atypical Tetratricopeptide Repeat Motif and Is a Negative Regulator of GroEL

Many proteins contain a thioredoxin (Trx)-like domain fused with one or more partner domains that diversify protein function by the modular construction of new molecules. The Escherichia coli protein YbbN is a Trx-like protein that contains a C-terminal domain with low homology to tetratricopeptide repeat motifs. YbbN has been proposed to act as a chaperone or co-chaperone that aids in heat stress response and DNA synthesis. We report the crystal structure of YbbN, which is an elongated molecule with a mobile Trx domain and four atypical tetratricopeptide repeat motifs. The Trx domain lacks a canonical CXXC active site architecture and is not a functional oxidoreductase. A variety of proteins in E. coli interact with YbbN, including multiple ribosomal protein subunits and a strong interaction with GroEL. YbbN acts as a mild inhibitor of GroESL chaperonin function and ATPase activity, suggesting that it is a negative regulator of the GroESL system. Combined with previous observations that YbbN enhances the DnaK-DnaJ-GrpE chaperone system, we propose that YbbN coordinately regulates the activities of these two prokaryotic chaperones, thereby helping to direct client protein traffic initially to DnaK. Therefore, YbbN may play a role in integrating the activities of different chaperone pathways in E. coli and related bacteria.
A case of bovine ketoacidosis in a lactating woman

A 36 year-old 5 weeks postpartum lactating woman presented to the emergency room with severe nausea and vomiting for 48 hours. The patient was found to be in non-diabetic ketoacidosis with a serum pH 6.9 and a HCO3 of <5mEq/L. This condition rapidly improved with the administration of intravenous dextrose and bicarbonate and with the cessation of breast feeding. The course and pathophysiology of the rarely described phenomenon of bovine ketosis in a human is discussed here.
Cellulite treatment: evidence and ethics, brief history, and emphasis on current practices including liposuction

According to Taber's Cyclopedic Medical Dictionary "cellulite" is defined as: "a non-technical term for subcutaneous deposits of fat, especially in the buttocks, legs, and thighs." These deposits result in puckered, dimply skin and they are a cause for major aesthetic concerns in affected patients. The etiology of this condition is still unclear. Female predilection is witnessed in clinical practice as it is reported in the literature. It remains a subject for further studies whether it is a structural problem of connective tissue or as suggested probably related to hormonal causes. Magnetic resonance imaging may provide some answers to these questions. Not knowing what is causing this nuisance makes it almost impossible to treat. No wonder that there is little scientific validation to support any of the many treatments that are advertised on the Internet or in women's magazines. This review focuses on mechanical and microinvasive interventions that claim to alleviate "cellulite": lipoplasty, liposcultpure, liposuction, subcision, and laser. Among the parameters analyzed are the proposed modes of action of these techniques as well as adverse events and complications that may occur. Of special interest will be the evidence that backs these procedures. Extracting reliable data is hampered by methodical problems with the design of most of the published trials. In essence, at this time there is no "cure" for cellulite. Safe treatment recommendations are related to healthy life style choices that include toning exercises, dietary changes, and weight loss.
Neural-network-based motor rolling bearing fault diagnosis

Motor systems are very important in modern society. They convert almost 60% of the electricity produced in the US into other forms of energy to provide power to other equipment. In the performance of all motor systems, bearings play an important role. Many problems arising in motor operations are linked to bearing faults. In many cases, the accuracy of the instruments and devices used to monitor and control the motor system is highly dependent on the dynamic performance of the motor bearings. Thus, fault diagnosis of a motor system is inseparably related to the diagnosis of the bearing assembly. In this paper, bearing vibration frequency features are discussed for motor bearing fault diagnosis. This paper then presents an approach for motor rolling bearing fault diagnosis using neural networks and time/frequency-domain bearing vibration analysis. Vibration simulation is used to assist in the design of various motor rolling bearing fault diagnosis strategies. Both simulation and real-world testing results obtained indicate that neural networks can be effective agents in the diagnosis of various motor bearing faults through the measurement and interpretation of motor bearing vibration signatures.
Configural Display Design Techniques Considered at Multiple Levels of Evaluation

Two studies were conducted to examine issues in the design and evaluation of configural displays. Four design techniques (bar graphs/extenders, scale markers/ scale grids, color coding/color layering/color separation, and annotation with digital values) were applied, alone and in combination, to a baseline configural display, forming 10 displays. Two qualitatively different evaluations assessed performance for (A) low-level data probes (quantitative estimates of individual variables) and (B) system control and fault detection tasks. Three of the four design techniques improved performance significantly for low-level data probes (color coding was the exception). A display with digital values only (i.e., no analog configural display) produced the poorest performance for control/fault detection tasks. When both levels of evaluation are considered, a composite display (configural display with all four techniques applied) was clearly the most effective. Overall, the findings obtained in the two experiments provide very limited evidence for the generalization of results between evaluations. The two levels of evaluation, the display manipulations, and the patterns of results are considered in terms of a cognitive systems engineering evaluation framework. General implications for the evaluation of displays and interfaces are discussed. Actual or potential applications include design techniques to improve graphical displays and methodological insights to focus and improve evaluation efforts.
Hyperdynamic circulation in a chronic murine schistosomiasis model of portal hypertension.

Chronic murine schistosomiasis is a natural disease model of portal hypertension closely mimicking the clinical and histological features of human hepatic schistosomiasis. We studied the splanchnic and systemic hemodynamics in the murine model of schistosomiasis by radioactive microsphere technique. Mice infected with 60 cercariae of Schistosoma mansoni (n = 8) were studied hemodynamically 11 wk after the infection and were compared with age-matched healthy controls (n = 11). Mean portal venous inflow in the infected mice (3.82 ± 0.32 ml/min) was 61% higher than in the healthy animals (2.37 ± 0.25 ml/min; p < 0.01). A twofold increase in hepatic arterial flow was also seen in mice with schistosomiasis (0.47 ± 0.14 ml/min) as compared with controls (0.16 ± 0.03 ml/min; p < 0.05), whereas splanchnic arteriolar resistance (60.91 ± 7.64 vs. 101.21 ± 11.06 mm Hg · min · ml−1. gm; p < 0.05) and peripheral vascular resistance (112.05 ± 14.05 vs 254.53 ± 29.86 mm Hg · min ml−1 · gm; p < 0.01) were reduced. There was a significant increase in cardiac index (752 ± 99 vs. 453 ± 55 ml · min−1 · kg body weight−1; p < 0.05) and reduction in mean arterial pressure (81.37 ± 3.09 vs. 101.45 ± 5.85 mm Hg; p < 0.05) in the infected animals compared with controls. These observations clearly demonstrate the existence of a hyperdynamic circulatory state in this model of portal hypertension. (HEPATOLOGY 1991;13:581–584.)