cssi/SciSciGPT-SciSciNet huggingface dataset:
In Honor of W.E. Moerner: Confining Molecules for Single-Molecule Spectroscopy

Single-molecule spectroscopy provides a wealth of information on the dynamics and interactions of complex biological molecules. Yet these mea- surements are extremely challenging, partly because Brownian motion prevents molecules in free solution from remaining stationary. Here we describe several techniques that our lab has developed for confining single molecules for optical spectroscopy. These alternatives to surface immobilization provide confinement that is gentle enough to minimize perturbations to the molecule, but strong enough to allow long-time imaging of single fluorescent molecules, often in the presence of a high fluorescent background.
Effects of prolonged vibration on motor unit activity and motor performance.

Excitatory input to the [alpha] motor neuron pool from Ia afferents is enhanced by brief vibration, yet is depressed when vibration is applied for prolonged periods. The purpose of this article is to synthesize recent findings from several studies on the effects of prolonged vibration on motor unit activity and motor performance during maximal and submaximal contractions in humans. Prolonged vibration does not alter voluntary drive during maximal contractions, but it does reduce Ia afferent input to [alpha] motor neuron pools and discharge rate of motor units in the vibrated muscles, leading to a reduction in maximal voluntary contraction force. Alterations in the activity of the motor unit pool may be variable across synergistic muscles due to potential neural connections between synergistic muscles. Prolonged vibration reduces the force fluctuations during submaximal steady contractions, presumably due to a depression of group Ia feedback from leg muscles. When prolonged vibration evokes a tonic vibration reflex in a hand muscle, the mean discharge rate of motor units during a submaximal force-matching contraction increases, leading to an increase in the associated force fluctuations. In summary, prolonged vibration modulates Ia feedback and motor unit activity, which leads to reduced peak force during maximal contractions and altered force fluctuations during submaximal contractions.
Thermal conductivity of impurity-doped high- T c superconductors

The thermal conductivity K(T) of polycrystalline ${\mathrm{YBa}}_{2}$(${\mathrm{Cu}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$${\mathit{M}}_{\mathit{x}}$${)}_{3}$${\mathrm{O}}_{7}$ with M=Zn and Al (0\ensuremath{\le}x\ensuremath{\le}0.1) and ${\mathrm{Y}}_{1\mathrm{\ensuremath{-}}\mathit{y}}$${\mathit{R}}_{\mathit{y}}$${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ with R=Pr and Gd (0\ensuremath{\le}y\ensuremath{\le}1.0) has been measured for temperatures 1.2\ensuremath{\le}T\ensuremath{\le}200 K. In the pure material, K(T) decreases slightly with decreasing temperature above ${\mathit{T}}_{\mathit{c}}$ and below ${\mathit{T}}_{\mathit{c}}$ there is a strong enhancement of K(T) reaching a maximum at \ensuremath{\sim}50 K followed by a sharp decrease. At temperatures below 10 K a ${\mathit{T}}^{2}$ dependence is evident similar to behavior reported for amorphous systems with glasslike phonon scattering on the tunneling states. Doping with Zn or Pr rapidly depresses ${\mathit{T}}_{\mathit{c}}$ and also depresses the maximum in K(T) even at concentrations that remain superconducting. This effect is observable to a lesser degree for the Al and Gd dopants. Comparisons between the K(T) behavior for impurities that do not depress ${\mathit{T}}_{\mathit{c}}$ with those that diversely alter the superconducting properties are presented together with an analysis of the data using the Tewordt-W\"olkhausen (TW) theory.
I own this language that everybody speaks: Ghanaians’ attitude toward the English language

Based on interviews conducted in ten Catholic churches of the Ghanaian capital, Accra, the paper offers a profile of English use in Ghana and reports on the attitudes of Ghanaians toward English as the official language of their country. The results reveal the influential role English plays in the different settings of Ghanaian communication as well as the high esteem afforded to the English language by the majority of Ghanaian respondents. Most of them cited the numerous benefits that English, as a language of wider communication, brings to the individual speaker and the country.
The fate of chlorine in recirculating cooling towers Field results

Abstract The chlorine added to recirculating cooling towers is consumed by chlorine demand, blowdown and flashoff (volatilization) to the air flowing through the tower. In order to understand the relative and absolute importance of these three sinks, we measured the free available chlorine (FAC) and the rate of chlorine demand by recirculating and makeup waters of a 1,200,000 gallon transverse flow, forced draft cooling tower. These data, together with known data on the circulation rate, blowdown rate, chlorine addition rate and flashoff (volatility) factors, allowed us to solve a differential equation defining the FAC at all times during and after the shock chlorination cycle. No unknown parameters were required. We found good agreement between observed and calculated FAC throughout the cycle. The equation showed that for this particular tower about 10% of the added chlorine was flashed off, 2% was lost to blowdown and 88% was consumed by chlorine demand. Operation at pH 6.5 would greatly increase the fraction lost by flashoff.
The Spillover Consequences of an Enforcement-First U.S. Immigration Regime

In our introduction to this special issue, we describe how the immigration enforcement-first regime has consequences that extend beyond the supposed target population of undocumented immigrants and spill over to other groups, including legal permanent residents, U.S.-born Latinos/as, and other U.S.-born residents. The papers in this special issue address whether and how spillover effects exist and the form that they take. Often they include social, psychological, and in some cases, physical harm, and together they illustrate that directly or indirectly, U.S. policy’s emphasis on interior and external border enforcement affects all of us.
Effect of pH on cell viability and product yields in d-xylose fermentations by Candida shehatae

Candida shehatae were sequentially subjected to aerobic conditions for cellular growth, followed by anaerobic conditions for ethanol production from d-xylose at pH 2.5,4.5 and 6.0. Ethanol yields increased from 0.25 g/g to 0.37 g/g and xylitol yields decreased from 0.33 g/g to 0.1 g/g as the pH was increased from 2.5 to 6.0. Cell viability, measured by plate counts and methylene blue staining, decreased in all of the fermentations, following the switch from aerobic to anaerobic conditions. However, pH 6.0 was shown to extend cell viability and increase the final ethanol concentration from 45 g/l to 55 g/l, compared to the yield at pH 4.5.
Exploration of Social, Environmental, and Familial Influences on the Sexual Health Practices of Urban African American Adolescents

Despite efforts to examine social influences and provide interventions that lead to safer sexual practices for African American (AA) adolescent girls, statistics have demonstrated this population continues to have the highest rates of teen pregnancy and sexually transmitted infections (STIs) including HIV when compared with adolescent girls of other races. Guided by the principles of Black Feminist Thought and Photovoice and focus group methodology, this descriptive study aimed to discover the social realities influencing a group of eight AA adolescent girls aged 15 to 19 years. Data from individual interviews and a focus group session were collected from November 11, 2012, to February 1, 2013. Analysis of selected photographs, interviews, and focus group conversations through a feminist lens suggests AA adolescents of low socioeconomic status continue to foster racial and mental inferiority stereotypes by using their sexuality as a bargaining tool for acceptance, value, and even love.
Low-Coordinate Iron(II) Amido Complexes of β-Diketiminates: Synthesis, Structure, and Reactivity

The synthesis, structure, and reactivity of a series of low-coordinate Fe(II) diketiminate amido complexes are presented. Complexes LRFeNHAr (R = methyl, tert-butyl; Ar = para-tolyl, 2,6-xylyl, and 2,6-diisopropylphenyl) bind Lewis bases to give trigonal pyramidal and trigonal bipyramidal adducts. In the adducts, crystallographic and 1H NMR evidence supports the existence of agostic interactions in solid and solution states. Complexes LRFeNHAr may be oxidized using AgOTf, and the products LRFe(NHAr)(OTf) are characterized with 19F NMR spectroscopy, UV/vis spectrophotometry, solution magnetic measurements, elemental analysis, and, in one case, X-ray crystallography. In the structures of the iron(III) complexes LRFe(NHAr)(OTf) and LRFe(OtBu)(OTf), the angles at nitrogen and oxygen result from steric effects and not π-bonding. The reactions of the amido group of LRFeNHAr with weak acids (HCCPh and HOtBu) are consistent with a basic nitrogen atom, because the amido group is protonated by terminal alkynes and ...
When coming to campus is not an option: using web conferencing to deliver library instruction

Purpose – Owing to the growing number of online and commuting students at the University of West Georgia, the Instructional Services department at Ingram Library experimented with offering online synchronous library instruction. This paper aims to describe how it approached this problem and the findings from the initial attempts.Design/methodology/approach – The authors wanted to provide library instruction to online graduate students at the university. They worked with the staff development department to develop a pilot program for an online library instruction course using WIMBA web‐conferencing software.Findings – It was found that due to the limitations of technology, the authors had to reduce the amount of information they deliver in the same amount of time. It was also discovered that it is easy to be distracted by the technology and forget that clear communication with the users (students and faculty) are the key to any successful instruction program regardless of the delivery method.Originality/va...
Histidine kinases and two-component signal transduction systems

The phosphorylation of histidine is the first step in many signal transduction cascades in bacteria, yeast and higher plants. The transfer of a very reactive phosphoryl group from phosphorylated histidine kinase.to an. acceptor is an essential step in many cellular signaling responses.
The direct effect of graft compliance mismatch per se on development of host arterial intimal hyperplasia at the anastomotic interface

To study thedirect andsole effect of compliance mismatch on anastomotic intimal hyperplasia of the host arterial wall and to minimize possible confounding factors, dogs with a low thrombotic potential were selected as experimental subjects. Externally supported 6 cm × 5 mm Dacron grafts with a compliance value of approximately 1/300 of the host artery were implanted into the carotid arteries with end-to-end anastomoses on one side and end-to-side anastomoses on the other. The control graft was an autogenous carotid artery segment 4 cm in length transplanted into the femoral artery. Eight cases (24 grafts) were studied for 1 year and three (nine grafts) for 6 months. All were patent throughout the study period except for two noncompliant grafts with end-to-end anastomoses; thrombosis was the documented cause of occlusion. For the patent grafts, follow-up arteriograms showed no progressive narrowing of noncompliant anastomoses. Whether compliant or noncompliant, light microscopy studies showed slight intimal thickening within 1 to 2 mm of the anastomotic line, possibly the result of the normal healing response to stitch and surgical trauma. Quantitatively, 22 measurements representing longitudinal and circumferential thickness of the neointima were taken at each of the 40 patent noncompliant and 22 patent compliant control anastomoses. There was no statistically significant difference in anastomotic neointimal thickness in compliant and noncompliant grafts or for the different implantation periods. These data suggest that graft/host artery compliance mismatch does not cause arterial intimal hyperplasia at the anastomotic interface.
Introduction to the immunology of tuberculosis.

This paper serves to introduce some concepts of modern immunobiology that are relevant to the understanding of the complex interactions between mycobacteria and the infected host. Six topics are discussed: (1) the phenotypic markers and functions of human T lymphocyte subsets; (2) the nature of antigen receptors on T cells; (3) antigen processing and presentation; (4) adhesion molecules that facilitate cellular interactions; (5) surface molecules on phagocytes that promote the entry of pathogens into cells; and (6) compartmentalization of the immune system in vivo.
Effect of Permeate Flux and Tangential Flow on Membrane Fouling for Wastewater Treatment

Abstract Well-controlled membrane filtration experiments were performed to systematically investigate the effect of permeate flux and tangential flow (crossflow) on membrane fouling. Results were analyzed by the resistance-in-series model where the reason for flux decline was subdivided into adsorption, concentration polarization, and reversible and irreversible fouling. A synthesized paper mill wastewater with mainly lignin and 2-chlorophenol, biological suspension (activated sludge), and their mixture were used as feed solutions for ultrafiltration (30 000 Da) and microfiltration (0.3 μm) at different concentrations. The filtration experiments demonstrated that permeate flux declined faster with increasing feed concentration and membrane pore size and with decreasing tangential flow. The biological suspension rather than wastewater quality was a major cause for permeate flux decline in membrane bioreactors. In the absence of permeate flux, filtration resistance by foulants adsorption was negligible, as compared to total filtration resistance in the presence of permeate flux. It was also shown that tangential flow had almost no effect on the decline rate of permeate flux at pseudo steady state. Membrane cleaning results revealed that, in the absence of tangential flow, permeate flux decline was dominantly caused by reversible fouling. On the other hand, tangential flow caused slightly higher irreversible fouling due to higher permeation drag, as compared to the case of absence of tangential flow. Autopsy of fouled membranes suggested that the irreversible fouling layer was initially formed by pore blocking of small particles followed by strong interaction of fouling layer with mainly dissolved materials and by fouling layer compaction due to permeation drag.
Unmasking of Partial Diabetes Insipidus during Stress but Not Maintenance Dosing of Glucocorticoids in an Infant with Septo-Optic Dysplasia

Background. It is well acknowledged that glucocorticoid (GC) replacement can unmask diabetes insipidus (DI) in subjects with hypopituitarism. Objective. To increase the awareness and monitoring for transient and symptomatic DI in children with partial hypopituitarism during periods in which increased GC needs are required. Methods/Case. A 2-month-old female infant with septo-optic dysplasia (SOD; on thyroid and maintenance GC replacement therapy at 8 mg/m2/day) developed transient DI during 2 separate episodes of stress (one hypothermia, one febrile) when stress dosing of GC (25 mg/m2/day) was instituted. Conclusion. Children not diagnosed with DI during initial evaluation for hypopituitarism may benefit from rescreening of serum sodium levels during acute periods of stress that demand "stress" GC dosing. This will permit treatment and/or increased vigilance for ensuing permanent DI.
Dystrophic calcification in the tongue: a late sequel to radiation therapy.

I nterstitial radiotherapy consists of the direct implantation of radioactive sources into and around malignant tissues. Removable implants are used to deliver a specific dose, after which the radioactive source is removed, while permanent implants are left in place. The principal value of interstitial therapy is in delivering a high radiation dose to a small volume. This technique is useful in the treatment of selected small lesions and in boosting the radiation dose in conjunction with external beam therapy. Less frequently, it is used as a means of re-treatment following local recurrence in patients who are not surgical candidates and in whom external beam therapy would not be suitable.le3 Advantages of interstitial implants are their limited side effects and a paucity of late sequelae.“-” Some disadvantages of interstitial therapy include heterogeneous dose distribution, the occasional tendency for a localized area to receive an intense radiation dose (hot spot), which may lead to necrosis, and the invasive nature of the procedure itself.3* 4 Because of the uneven dosage from interstitial implants and the risk of not covering an adequate area of involvement, external irradiation in combination with interstitial implants is sometimes used for oral tumors.4. 6 Recently developed sophisticated computer dosimetry programs have facilitated the calculation of dose distribution within the tumor volume.7 Radium needles (removable), gold198 seeds (permanent), and radon-222 seeds (permanent) have been used as implants in the treatment of oral carcinomas for over 50 years. More recently, iridium192 wire and seeds and iodine125 seeds have become frequently used as implants because of their advantages of economy, relatively short half-life, and improved radiation safety.2, H Among the well-documented side effects of head and neck irradiation are xerostomia, mucositis, chondritis, and dental caries. The development of osteonecrosis as a complication of radiation has been less frequently observed since the advent of supervoltage
Passage of infectious nuclear polyhedrosis virus through the alimentary tracts of two small mammal predators of the gypsy moth, Lymantria dispar

The white-footed mouse, Peromyscus leucopus Rafinesque, and the short-tailed shrew, Blarina brevicauda Say, 2 small mammal predators of the gypsy moth, have demonstrated the ability to pass significant amounts of infectious nuclear polyhedrosis virus (NPV) through their alimentary tracts. Ninety-five percent of the gypsy moth larvae fed fecal preparations from NPV-challenged mammals died during infectivity tests, whereas only 6% of larvae fed control fecal preparations died. The ability of these mammals to pass large amounts of infectious NPV may be important in the distribution of NPV in the wild.
Changes in the protein nutritional status of adolescent wrestlers.

The protein nutritional status of adolescent wrestlers was studied to determine whether changes occur during a season of competition and weight loss. Subjects (N = 18) were measured prior to the start of the season (PRE), twice in the midseason, and once during late season (LATE) for weight, percent body fat, and height. At each of these times, a venous blood sample was obtained from the subjects, who were fasted, and analyzed for concentrations of albumin, prealbumin, retinol binding protein (RBP), blood urea nitrogen (BUN), hemoglobin, hematocrit, and 23 amino acids. Diet records were kept by subjects to assess daily energy, protein, fat, and carbohydrate intake. Data were analyzed by repeated measures ANOVA. Results showed that wrestlers decreased weight by an average of 6.6 +/- 0.9% and that percent body fat, fat-free weight, plasma levels of prealbumin and RBP, the ratio of total essential amino acids to total amino acids, and dietary energy nutrient intakes were significantly lower at LATE compared to PRE. RBP decreased during midseason and averaged (+/- SE) 3.21 +/- 0.15 mg.100 ml-1 at LATE; prealbumin was significantly lower at LATE with a mean value of 19.8 +/- 1.0 mg.100 ml-1. Total energy intake decreased from PRE values by 35%, to approximately 27 kcal.kg-1.d-1 during the season. In conclusion, in these high school wrestlers who lost approximately 6.6% of weight, there were adverse effects on some of the indices of protein nutritional status.
Role of the 14–3–3 protein in carbon metabolism of the pathogenic yeast Candida albicans

We previously demonstrated that the pathogenic yeast Candida albicans effectively adapts to utilize L-sorbose (Sou+) by a novel mechanism based on the loss of one copy of chromosome 5, probably due to the reduction of copy number of a negative regulator located on this chromosome. We report here another negative regulator of L-sorbose utilization, an orthologue of the Saccharomyces cerevisiae BMH1 gene, which encodes the evolutionarily conserved protein 14–3–3. This essential gene is located on chromosome 1, does not have paralogues, and is supposedly a component of the regulatory network. Experiments involving disruption of one allele of BMH1 and overexpression of BMH1 revealed that BMH1 represses the transcription of SOU1, which is responsible for the utilization of L-sorbose. Although the exact mechanism of the interaction between BMH1 and SOU1 is not known, it is clear that the control is based on the ratio of gene copy number, and that BMH1 does not control the loss of chromosome 5, the major mechanism producing Sou+ mutants. We propose that function of BMH1 as a negative regulator of SOU1 contributes to a general cellular homeostasis. This is a first report on the role of the C. albicans essential gene BMH1 as a negative regulator of the utilization of secondary carbon source in yeast, which further substantiates the involvement of 14–3–3 proteins in diverse functions. Copyright © 2004 John Wiley & Sons, Ltd.
Wiener analysis of nonlinear systems using Poisson-Charlier crosscorrelation

Nonlinear systems with event-sequence input, such as are often encountered in neurophysiology, may be experimentally tested with all possible input sequences by stimulation with a Poisson process eventsequence. A complete predictive model of the system's response may be constructed from this data with the Wiener expansion based on the Poisson-Charlier polynomials. Here it is shown how this formulation leads to an efficient method for the evaluation of unknown systems by crosscorrelation, generalizing previous methods. The basic statistical properties of the procedure are demonstrated and the length of experiment required for accurate estimation of the model is computed. The procedure is translated into digital algorithms and the analogous procedures for white noise analysis are presented.
Metamorphism in the Martian crust

Compositions of basaltic and ultramafic rocks analyzed by Mars rovers and occurring as Martian meteorites allow predictions of metamorphic mineral assemblages that would form under various thermophysical conditions. Key minerals identified by remote sensing roughly constrain temperatures and pressures in the Martian crust. We use a traditional metamorphic approach (phase diagrams) to assess low-grade/hydrothermal equilibrium assemblages. Basaltic rocks should produce chlorite + actinolite + albite + silica, accompanied by laumontite, pumpellyite, prehnite, or serpentine/talc. Only prehnite-bearing assemblages have been spectrally identified on Mars, although laumontite and pumpellyite have spectra similar to other uncharacterized zeolites and phyllosilicates. Ultramafic rocks are predicted to produce serpentine, talc, and magnesite, all of which have been detected spectrally on Mars. Mineral assemblages in both basaltic and ultramafic rocks constrain fluid compositions to be H2O-rich and CO2-poor. We confirm the hypothesis that low-grade/hydrothermal metamorphism affected the Noachian crust on Mars, which has been excavated in large craters. We estimate the geothermal gradient (>20 °C km−1) required to produce the observed assemblages. This gradient is higher than that estimated from radiogenic heat-producing elements in the crust, suggesting extra heating by regional hydrothermal activity.
Incremental development productivity decline

Incremental models are now being used by many organizations in order to reduce development risks while trying to deliver the product on time. It has become the most common method of software development with characteristics that influences the productivity of projects.This paper introduces a phenomenon called Incremental Development Productivity Decline (IDPD) that is presumed to be present in all incremental software projects to some extent.Different ways of measuring productivity are presented and evaluated in order to come to a definition or set of definitions that is suitable to these kinds of projects.Based on their coherence and other common characteristics, incrementally developed projects are split into several major categories.Following this, several major projects are used as case studies in order to find out whether IDPD can be proven to exist.
Neutron energy-dependent damage function for analysis of austenitic steel creep data☆

Abstract Proper correlation and subsequent application of irradiation-effects data for materials exposed in different reactor environments depend upon a knownledge of the energy dependence of neutron damage. A theoretical model of neutron damage in austenitic steel was adjusted with available creep-strain data for austenitic steel irradiated at temperatures below ∼ 400°C. This procedure yielded a damage function for the neutron-energy dependence of irradiation-induced creep-strain. Although the derived damage function correlates available creep data, it is only roughly defined and is presented to meet immediate demands for such correlation. Additional and more accurate flux-spectral, fluence and property-change data for more test reactor environments are required to confirm the adequacy of the damage function. As a means of interpreting and correlating available test-reactor data for application to different environments, the present damage function will help establish proper engineering design requirements for use of austenitic steels in fast test, thermal test, and power reactors. The damage function is now being used to analyze irradiation conditions in the Fast Test Reactor (FTR) among others.
Folk names and uses for martyniaceous plants

Folk names and uses for martyniaceous plants are detailed by literature references, data from herbarium specimens and fieldwork in Mexico and the United States. There is a diversity of names and uses in Mexico because of the large number of species and the many different cultures there. Seeds, roots, and leaves of species ofProboscidea are gathered and consumed as food. Leaves ofMartynia are used to remove insects from fowl in Mexico and Guatemala, and its fruits are used medicinally in the former country. Most Mexican common names for martyniaceous plants are descriptive, and the folk taxonomies for these plants often agree with scientific taxonomies. The showy and fragrant flowers and oddly-shaped fruits ofProboscidea, Ibicella, andMartynia led to their cultivation as ornamentals in the United States and Europe. The common names for martyniaceous plants in European languages are generally variations of devil’s claw, cat’s claw, or unicorn plants. Young fruits ofProboscidea andIbicella are eaten as vegetables and pickles in the United States, South America, and Europe. Mature fruits ofProboscidea are widely used as ornaments. Roots from species ofCraniolaria are consumed as food or medicine in South America and the Antilles.
The Genesis total knee prosthesis: a 10-year followup study.

This current author reports on the results of 100 consecutive patients with osteoarthritis who underwent a primary cemented total knee replacement using the Genesis prosthesis and who have been followed up for at least 10 years after surgery. In patients in whom the posterior cruciate ligament was sacrificed (combined flexion and angular deformities > 15° to 20°) a posterior-stabilized cam module was affixed to the femoral component and a posterior-stabilized polyethylene was used. More than 95% of patients in both groups had excellent pain relief. The mean flexion was 114° in the group of patients in whom the posterior cruciate ligament was sacrificed and 117° in the group of patients in whom the posterior cruciate ligament was retained. Partial bone cement tibial radiolucencies were seen in 12% of the patients in whom the posterior cruciate ligament was retained and 2% of the patients in whom the posterior cruciate ligament was sacrificed. At 10 years, 76% of the group in whom the posterior cruciate ligament was retained had excellent results and 20% had good results. In the group in whom the posterior cruciate ligament was sacrificed 75% had excellent results and 23% had good results. The survivorship was 96% in the group of patients in whom the posterior cruciate ligament was retained and 97% in the group of patients in whom the posterior cruciate ligament was sacrificed.
Vasopressin in the rat with partial nephrectomy-salt hypertension.

The role of vasopressin in the pathogenesis of partial ne-phrectomy (PN)-salt hypertension was examined in the rat. Hypertension was produced by reducing renal mass 70% and substituting 1% saline for drinking water 2 to 4 days after surgery. PN alone resulted in an increase in systolic blood pressure. Subsequent salt loading led to a further large increase in arterial pressure. On the second to third day after substitution of saline for drinking water, urinary vasopressin excretion (UADHV) was increased six-fold and the plasma vasopressin concentration was increased two and one-half-fold. UADHV) then fell to a level that was threefold greater than control values 5 days later. Although there was a marked stimulation of vasopressin release during the period of
Thyroid hormone metabolism and level of illness severity in pediatric cardiac surgery patients.

To define better the temporal relationship between alterations in thyroid hormone metabolism and changes in illness severity, we studied thyroid function in 12 children preoperatively and at 2, 12, 24, 48, and 72 hours after cardiac surgery. We then compared these findings with illness severity as assessed by a modification of the Therapeutic Intervention Scoring System (TISS). All patients had significant ( p 3 (mean 35% of baseline levels) and elevation in serum rT 3 (mean 237% of baseline levels) in the postoperative period. Average correlation coefficients for the combined data were as follows: TISS and T 3 , levels, −0.63±0.17; TISS and rT 3 levels, 0.51±0.18. Examination of individual patient data normalized to preoperative T 3 and rT 3 levels and compared with TISS scores demonstrated a lag in alterations of serum rT 3 and T 3 levels relative to illness severity during recovery from cardiac surgery. We conclude (1) the euthyroid sick syndrome occurs in all pediatric cardiac surgery patients, regardless of procedure complexity, (2) changes in rT 3 levels parallel but follow changes in degree of therapeutic intervention, indicating that these alterations result from, and do not cause, increasing severity of illness, (3) rT 3 levels return toward normal before T 3 levels, which remain low beyond the critical postoperative period, and (4) clinical indicators of illness severity are fairly well inversely correlated with T 3 levels, supporting an adaptive reduction in 5′-deiodinase activity during the postoperative period.
Plasma prednisolone concentrations: Comparison of radioimmunoassay and competitive protein binding assay

Abstract A comparison was made between plasma concentrations of prednisolone measured by both competitive protein binding radioassay (CPB) and radioimmunoassay (RIA) and, with each assay, using a calibration curve generated from individual subject data and from pooling the individual calibration curve data. The plasma samples were obtained from six normal adult male volunteers who were pretreated with dexamethasone to suppress endogenous hydrocortisone and who then ingested 10 mg of prednisolone. Both the standard curve data and the plasma concentrations were evaluated statistically. It was shown that the CPB method has considerably greater precision than the RIA method and could be employed in bioavailability and pharmacokinetic studies of both prednisolone and prednisone. It was also shown that corticosteroid binding globulin cross-reacts considerably less with the major metabolite of prednisolone, 20β-dihydroprednisolone, than the particular antiserum used in the RIA.
Climate adaptation, local institutions, and rural livelihoods: A comparative study of herder communities in Mongolia and Inner Mongolia, China

Abstract Climate variability has been evident on the Mongolian plateau in recent decades. Livelihood adaptation to climate variability is important for local sustainable development. This paper applies an analytical framework focused on adaptation, institutions, and livelihoods to study climate adaptation in the Mongolian grasslands. A household survey was designed and implemented in each of three broad vegetation types in Mongolia and Inner Mongolia. The analytical results show that livelihood adaptation strategies of herders vary greatly across the border between Mongolia and Inner Mongolia, China. Local institutions played important roles in shaping and facilitating livelihood adaptation strategies of herders. Mobility and communal pooling were the two key categories of adaptation strategies in Mongolia, and they were shaped and facilitated by local communal institutions. Storage, livelihood diversification, and market exchange were the three key categories of adaptation strategies in Inner Mongolia, and they were mainly shaped and facilitated by local government and market institutions. Local institutions enhanced but also at times undermined adaptive capacity of herder communities in the two countries, but in different ways. Sedentary grazing has increased livelihood vulnerability of herders to climate variability and change. With grazing sedentarization, the purchase and storage of forage has become an important strategy of herders to adapt to the highly variable climate. The multilevel statistical models of forage purchasing behaviors show that the strategies of livestock management, household financial capital, environmental (i.e., precipitation and vegetation growth) variability, and the status of pasture degradation were the major determinants of this adaptation strategy.
Ammonium regeneration and carbon utilization by marine bacteria grown on mixed substrates

We examined the impact of exposing natural populations of marine bacteria (from seawater collected near Woods Hole, Massachusetts, USA) to multiple nitrogen and carbon sources in a series of batch growth experiments conducted from 1989 through 1990. The substrate C:N ratio (C:Ns) was varied from 1.5:1 to 10:1 either with equal amounts of NH 4 + and different amino acids or an amino acid mixture, all supplemented with glucose to maintain the C:Ns ratio equal to that of the respective amino acid, or with combinations of glucose and NH 4 + alone. A common feature of the experiments involving amino acids was the concurrent uptake of NH 4 + and amino acids that persisted as long as a readily assimilable carbon source (glucose in our case) was taken up. There was no net regeneration of NH 4 + , even though catabolism of amino acids occurred. Regeneration of NH 4 + was evident only after glucose was completely utilized, which usually occurred at the end of exponential growth. The contribution of15NH 4 + to total nitrogen uptake by the end of exponential growth varied from ~60 to 80% when individual amino acids were present and down to ~24% when the amino acid mixture was added. These estimates are conservative because we did not account for possible isotope dilution effects resulting from amino acid catabolism. When NH 4 + and glucose were the sole nitrogen and carbon sources, there was a stoichiometric balance between glucose and NH 4 + uptake over a wide range of C:Ns ratios, leading to a constant bacterial biomass C:N ratio (C:NB) of ~4.5:1. As a result NH 4 + usage varied from 50% when the C:Ns ratio was 3.6:1, to 100% when the C:Ns ratio was 10:1. Gross growth efficiency varied from ~60% when NH 4 + plus glucose were added alone or with the amino acid mixture, to 47% when the individual amino acids were used in place of the mixture. It is thus evident that actively growing bacteria will act as sinks for nitrogen when a carbon source that can be assimilated easily is available to balance NH 4 + uptake, even when amino acids are available and are being co-metabolized.
Vascular connexins have differing responses to tumor necrosis factor

Cell-to-cell communication via gap junctions has been implicated in the control of vascular tone and may be altered in sepsis. Endothelial cells express connexin (Cx) 37, Cx40 and Cx43 and cytokines may modulate their function in sepsis resulting in altered gap junctional intercellular communication. Our hypothesis is that tumor necrosis factor (TNF) will decrease gap-junction-dependent cell-to-cell communication of vascular connexin.
31P-NMR studies of Mycoplasma gallisepticum cells using a continuous perfusion technique.

Abstract 31P-NMR studies of Mycoplasma gallisepticum cells have been carried out using a continuous perfusion technique; these are the first such studies with this organism. Using this technique, glucose metabolism was monitored in the intact organisms, and cell extracts were prepared to identify the intermediates. Under glycolytic conditions, high levels of fructose-1,6-diphosphate were observed, indicating that this sugar may play a key role in the regulation of metabolism. The level of phosphoenolpyruvate was low under normal glycolytic conditions, and did not increase during starvation. From the position of the internal inorganic phosphate peak, the intracellular pH was estimated. The cells were found to maintain an intracellular pH of ~ 7.1 over an investigated external pH range of 6.6–8.6.
Glutamine- vs glucose-supported motor activity in Schistosoma mansoni: physiological relevance of aerobic metabolism.

Abstract The ability of Schistosoma mansoni to generate energy through aerobic metabolic processes was examined in adult parasites in vitro . Parasite catabolism of radiolabeled glucose, glutamine, and other amino acids to CO 2 and Krebs cycle intermediates was measured under a variety of incubation conditions. l -Glutamine was metabolized to CO 2 via the intermediates glutamate, α-ketoglutaramate, and α-ketoglutarate in worms incubated in a balanced salts solution containing this amino acid as the only organic constituent. Of the other amino acids tested, CO 2 production was detected from l -glutamate and l -asparagine. The catabolism of l -glutamine to CO 2 was reduced by the respiratory inhibitor antimycin A. The motility of schistosomes in culture was maintained for at least 24 hr when l -glutamine was the only carbon source available to the worms. Under these conditions, motility was reduced when parasites were exposed to a respiratory inhibitor such as KCN, antimycin A, rotenone, or oligomycin, but it was completely restored by the addition of glucose to the medium. These results suggest that while the schistosome is capable of limited aerobic energy-generating processes under certain conditions, survival is not contingent upon these processes in the presence of glucose.
Preferential Nucleation of Metallic Clusters on a Nanotemplate: Co on Oxygen-Faceted Re(12 \overline{3} 1)

Preferential nucleation of cobalt nanoclusters at specific sites on oxidized faceted Re(12 $$ \overline{3} $$ 1) is investigated by means of Auger electron spectroscopy (AES), low energy electron diffraction (LEED), and scanning tunneling microscopy (STM). An oxygen terminated nanofaceted Re surface containing ridges and valleys is used as the nanotemplate in this study. Deposition of cobalt onto this surface, followed by annealing to ~800 K, results in preferential cobalt nanocluster nucleation and growth within the valleys of the nanofaceted surface. Decreasing the nanofacet width, cobalt coverage, and annealing temperature lead to the same preferential cobalt nanocluster self assembly, an increase in nanocluster density, and a decrease in nanocluster volume. The preferential nucleation and growth observed for Co nanoclusters on faceted Re makes this a model system for future studies of different substrates and metallic overlayers more relevant to catalytic reactions.
Vertebral compression fractures in patients presenting with metastatic epidural spinal cord compression.

Objective Metastatic epidural spinal cord compression (MESCC) is a relatively common and debilitating complication of metastatic disease that often results in neurological deficits. Pathological fractures of the vertebral body in patients with MESCC are not uncommon. The goals of this study were to evaluate the effects of compression fractures on long-term neurological function, as well as understand the factors that predict the development of pathological fractures for patients with MESCC. Methods One hundred sixty-two patients undergoing decompressive surgery for MESCC at an academic tertiary care institution from 1995 to 2007 were retrospectively reviewed. Multivariate proportional hazards regression analysis was used to assess the effects of pathological vertebral body fractures on ambulatory outcome, whereas multivariate logistical regression analysis was used to identify factors associated with preoperative compression fractures. Results Sixty and 102 patients presented with and without pathological vertebral body fractures, respectively, and MESCC. Patients were followed for a mean of 9.7 +/- 2.6 months. The presence of preoperative compression fractures was independently associated with decreased postoperative ambulatory status (odds ratio, 2.106; 95% confidence interval, 1.123-4.355; P = 0.03). This was independent of age, preoperative ambulatory status, preoperative motor deficit, duration of preoperative symptoms, immediate postoperative motor deficit, and lytic tumor appearance. The factors strongly associated with preoperative compression fractures in this study include lack of sensory deficits (P = 0.01), primary breast cancer (P = 0.008), anterior spine metastases (P = 0.005), thoracic spine involvement (P = 0.01), preoperative chemotherapy (P = 0.03), and, possibly, preoperative radiation therapy (P = 0.16). Conclusion The findings of this study may provide insight into risk stratifying as well as guiding surgical management for patients with MESCC.
Intramolecular sulfur-ylide additions to ketones. A cyclopentane annulation1

Abstract Various 2-(3′-phenylthiopropyl)cycloalkanones were prepared from the corresponding cyclic ketones and subjected to S-alkylation by triethyloxonium tetrafluoroborate followed by potassium tert -butoxide treatment to give bicyclic epoxides with new five-membered carbocycles. A related cyclization to a six-membered ring was also observed.
Network protocols: correcting transmission errors of up to two bits

While the construction of Hamming Codes that can detect and correct 1-bit transmission errors has been illustrated [1], Hamming Codes that will detect and correct transmission errors of more than 1 bit remain yet to be constructed. In this paper, how to build Group Codes that can correct transmission errors of up to 2 bits will be shown. Note that transmission control protocols such as TCP/IP rely upon the notion of checksums", a variation of Hamming Codes, for their transmission error correction. The ease and efficiency with which the group codes can be built will then be compared to those of Hamming Codes and Cyclic Redundancy Checking, the transmission error detection/correction schemes discussed in [1].
The effect of storage temperature on interactions between dehydrated sugars and phosphatidylcholine

We studied the effects of storage temperature on the stability of dehydrated POPC (1-palmitoyl-2-oleoyl-phosphatidylcholine) mixed with sucrose, trehalose, or a sucrose/raffinose mixture. We used DSC to measure the gel-to-fluid phase transition temperature (Tm) of POPC after incubation either below or near the glass transition temperature (Tg) of the sugars in the mixture. Glass formation by the sugars around fluid-phase POPC led to the lowering ofTm below that of the fully hydrated lipid. Phospholipid phase behavior did not change during storage belowTg. In some samples stored aboveTg, trehalose crystallized completely; in these samples, theTg of POPC increased to that of the partially dehydrated phospholipid. Melting the crystalline sugar re-established its ability to lower POPC'sTm. We conclude that prevention of complete sugar crystallization was important for stability in the dry state, and that storage belowTg conferred long-term stability to the dehydrated sugar-lipid mixtures.
Common loon parents defend chicks according to both value and vulnerability

In many territorial breeders, conspecifics that intrude during the chick-rearing period pose a threat to survival of young. Defense of young from intruders is costly to parents, so it is likely that intense selective pressure has shaped chick defense so as to maximize parental fitness. We simulated territorial intrusion by exposing adult common loons Gavia immer and their chicks to a decoy and used mixed models to investigate responses. We tested two hypotheses: 1) the value hypothesis, which holds that parents should defend large broods of offspring more strongly because of the greater potential fitness benefits they offer, and 2) the vulnerability hypothesis, which predicts vigorous defense of young offspring, whose small size and limited mobility render them vulnerable to sudden attacks from intruders that approach under water. Under natural conditions, parents spent over 80% of their time within 20 m of chicks younger than two weeks (‘young chicks’) but 66% or less of their time close to chicks four weeks or older (‘old chicks’). Parents of young chicks associated less with the decoy but yodelled and penguin danced more during decoy trials than did parents of old chicks, supporting the conclusion that the parents protected young chicks not by engaging intruders directly but by remaining close to chicks and using vocalization and display to keep intruders at a distance. While these findings lent clear support to the vulnerability hypothesis, the value hypothesis too was supported, as males with two-chick broods were almost three times more likely to yodel than males with singleton chicks. Age of parents was not associated with any aspect of chick defense, but the paucity of known-aged parents in the oldest age classes makes future investigation of age effects warranted.
Kinetic parameter estimation from attenuated SPECT projection measurements

Conventional analysis of dynamically acquired nuclear medicine data involves fitting kinetic models to time-activity curves generated from regions of interest defined on a temporal sequence of reconstructed images. However, images reconstructed from the inconsistent projections of a time-varying distribution of radiopharmaceutical acquired by a rotating SPECT system can contain artifacts that lead to biases in the estimated kinetic parameters. To overcome this problem the authors investigated the estimation of kinetic parameters directly from projection data by modeling the data acquisition process. To accomplish this it was necessary to parametrize the spatial and temporal distribution of the radiopharmaceutical within the SPECT field of view. In a simulated transverse slice, kinetic parameters were estimated for simple one compartment three myocardial regions of interest, as well as for the liver. Myocardial uptake and washout parameters estimated by conventional analysis of noiseless simulated data had biases ranging between 1-63%. Parameters estimated directly from the noiseless projection data were unbiased as expected, since the model used for fitting was faithful to the simulation. Predicted uncertainties (standard deviations) of the parameters obtained for 500,000 detected events ranged between 2-31% for the myocardial uptake parameters and 2-23% for the myocardial washout parameters.