cssi/SciSciGPT-SciSciNet huggingface dataset:
Immobilized Enzymes and Cells as Practical Catalysts

Performance of enzymes and whole cells in commercial applications can often be dramatically improved by immobilization of the biocatalysts, for instance, by their covalent attachment to or adsorption on solid supports, entrapment in polymeric gels, encapsulation, and cross-linking. The effect of immobilization on enzymatic properties and stability of biocatalysts is considered. Applications of immobilized enzymes and cells in the chemical, pharmaceutical, and food industries, in clinical and chemical analyses, and in medicine, as well as probable future trends in enzyme technology are discussed.
Friedreich's Ataxia in Childhood : Case Report with Possible Myocardial Infarction, Cerebrovascular Thromboembolization, and Persistent Elevation of Cardiac Specific LDH

A seven-year old Caucasian girl with Friedreich's ataxia, cerebral thromboembolism, possible repeated myocardial infarctions and severe cardiac involvement is presented. The father and a paternal uncle both died of myocardial infarction at an early age. Persistent elevation of LDH isoenzyme 5 following angina-like attacks is reported for the first time in Friedreich's ataxia and suggests continuing damage to the myocardium.
Unifying the little Picard, Lohwater–Pommerenke and Brody theorems

Abstract A theorem unifying the theorems of little Picard, Lohwater–Pommerenke and Brody is presented: Let M , Y be complex spaces. Then a family of holomorphic maps F ⊂ H ( M , Y ) is uniformly normal iff every F -limiting curve is trivial. Furthermore, Zalcman's lemma and the Robinson–Zalcman Heuristic Principle are ‘extended.’
Concentrations and Ruminal Degradabilities of Amino Triticale Forage and Grain

A study was conducted to provide comparative data on amino acid (AA) concentrations in forage and grain of wheat (Triticum aestivum L.) and triticale (x Thiticosecale Wittmack), before and after ruminal degradation, while assessing forage and grain yield potential. Forage samples of 'Terral 817' wheat, 'Jenkins' triticale, and 'Morrison' triticale were harvested at growth stages 5.0, 6.5, and 8.0 and AA concentrations and yield determined. Wheat and triticale forage samples were incubated in Dacron bags for 24 h in the rumen of cows to determine the comparative ruminal degradability of their EAA. Forage production among the three cultivars in 1987-1988 was similar, but in 1988-1989, Jenkins produced 15% more forage than Terral 817, which produced 14% more forage than Morrison. Essential amino acid concentrations in Jenkins triticale forage were equal to or greater than Terral 817 wheat or Morrison triticale ; however, Morrison grain had a greater concentration of all EAA, except lysine, than did grain of Terral 817 or Jenkins. The EAA in Terral 817 forage averaged 25% higher in potential degradability in the rumen than EAA in Jenkins. Terral 817 and Morrison maintained a higher grain yield response to forage removal in contrast to Jenkins. Differences in forage yield, grain yield, and EAA concentration could not always be separated by species. The data suggest that triticale may produce forage and grain yields equal or greater than that of winter wheat while providing a better source of ruminally undegradable EAA.
Plasmodium falciparum gametocyte development 1 (Pfgdv1) and gametocytogenesis early gene identification and commitment to sexual development.

Malaria transmission requires the production of male and female gametocytes in the human host followed by fertilization and sporogonic development in the mosquito midgut. Although essential for the spread of malaria through the population, little is known about the initiation of gametocytogenesis in vitro or in vivo. Using a gametocyte-defective parasite line and genetic complementation, we show that Plasmodium falciparum gametocyte development 1 gene (Pfgdv1), encoding a peri-nuclear protein, is critical for early sexual differentiation. Transcriptional analysis of Pfgdv1 negative and positive parasite lines identified a set of gametocytogenesis early genes (Pfge) that were significantly down-regulated (>10 fold) in the absence of Pfgdv1 and expression was restored after Pfgdv1 complementation. Progressive accumulation of Pfge transcripts during successive rounds of asexual replication in synchronized cultures suggests that gametocytes are induced continuously during asexual growth. Comparison of Pfge gene transcriptional profiles in patient samples divided the genes into two groups differing in their expression in mature circulating gametocytes and providing candidates to evaluate gametocyte induction and maturation separately in vivo. The expression profile of one of the early gametocyte specific genes, Pfge1, correlated significantly with asexual parasitemia, which is consistent with the ongoing induction of gametocytogenesis during asexual growth observed in vitro and reinforces the need for sustained transmission-blocking strategies to eliminate malaria.
Effect of outdoor aging on acrylic sheet

Abstract One of the prime contenders for solar reflectors or concentrators is acrylic plastic. Other than the basic requirement of being a highly efficient reflector or transmitter of the solar spectrum, it must offer excellent long-term weatherability with minimum cost. The weatherability of acrylic polymers, although known to be good compared to other polymers, has been an unknown with regard to actual exposure data in the southwestern United States, where the potential is high for solar energy installations. This report is a compilation of data obtained from an acrylic panel that has been exposed for over 17 years in the semi-arid desert terrain south of Albuquerque. New Mexico. A comparison is made with unexposed material having a very similar polymer structure. In general, chemical changes are not detectable while mechanical response shows some evidence of embrittlement. In spite of these, the decrease in optical transmission is surprisingly low. The as-recovered material (with dust-eroded surface) had an integrated or total transmittance which was 10 per cent less than the control material, based on a solar radiation spectrum. In order to isolate the degradation loss due to change in the basic polymer, a polished specimen of aged material was tested and showed only a 3 per cent drop in transmission across the solar spectrum. It appears reasonable that this low loss could be duplicated in a solar reflector provided the mirror is coated with an abrasion-resistant glass resin system.
Detection and analysis of recognition and selection in the immune response

Some theoretical requirements for the valid use of hemolytic plaque inhibition as a method for studying cellular selection and recognition in an immune response are reviewed. Aside from providing a rational basis for the use of this technique, the theory resolves a growing body of apparently conflicting results on the affinity regulation of IgM secreting cells and can also be used to deduce structural (in particular, morphological) features of the IgM molecule. The diverse predictions of the theory are examined in light of experimental results and find support in a wide data base. Additional specific experiments are proposed which can be used in conjunction with the theory to help clarify the relation between cellular proliferation and maturation.
Effects of long-term sodium deprivation on the adrenal cortices of rats: a histochemical study.

White male albino rats (80- 100 g) were placed on a sodium-deficient diet for a period of 48 weeks, after which time they were sacrificed, and the adrenals were removed and studied using histochemical techniques for the demonstration of glucose-6- phosphate dehydrogenase and sudanophilic lipids, and routine histological techniques. After 48 weeks the glomerulosas of these adrenal cortices were enlarged to a size about twice that of controls, but were not quite as enlarged as previously noted in short-term sodium deprivation (3 weeks) of adult rats (250 g), and much less than was observed on short-term deprivation of young animals (80- 100 g). In the long-term depleted animals, glucose-6-phosphate dehydrogenase activity was increased, but in 6 of 10 of these animals the increase was only slight and the pattern of enzyme distribution differed from that observed in the short-term depleted adult animal. Activity was generally much less intense than was observed in short-term depleted younger animals. Patterns...
The Synthesis and Characterization of SNAFR‐5 Derivatives

The synthesis and characterization of a new series of long wavelength and NIR-active dyes for use as diagnostic indicators in biological fluids has been carried out. The dyes are synthesized by a one-pot acid promoted condensation and isolated by flash column chromatography. Their structures are assigned by NMR and mass spectrometry. The spectral properties are evaluated by UV-vis and fluorescence spectroscopy. Preliminary spectroscopic data reveal these dyes exhibit anticipated characteristics that apparently meet the current requirements as NIR-active dye candidates for bioimaging and medical applications. Introduction Among the absorbing and emitting near infrared (NIR) dyes, there is only one that is FDA approved. Strongin has recently reviewed the current literatures on the synthesis and evaluation of new NIR dyes including phthalocyanines, cyanines, and squaraines. These exhibit many outstanding properties, but their use in biomedical research may be restricted by aqueous insolubility, aggregation, small Stoke’s shifts, and/or relatively larger molecular weight. Thus, there is a general need for simple innovative NIR-active dyes. Xanthene dyes such as fluorescein are relatively non-toxic to humans; however, they are typically not NIR active. To help meet criteria for medical purposes, fluorophores in the xanthene series that are being developed in the Strongin group reveal a combination of desirable traits including 1) comparatively low molecular weight, 2) aqueous solubility, 3) dual excitation and emission in the forms of neutral and anionic species, 4) readily attainable changes in the regiochemistry of benzannulation and the ionizable groups resulting in tunable deep-red to NIR emission, and 5) large Stoke’s shifts. The structures of SNAFR5 (seminaphthofluorone) derivatives investigated in my research are depicted in Fig.1. Herein I describe studies of 2.
Deployment algorithms and indoor experimental vehicles for studying mobile wireless sensor networks

Wireless communication has been traditionally used in robotics to transmit sensory and telemetry information between a robot and a base station. Because research in mobile robotics has typically focused on navigation, mapping and sensor fusion, network oriented problems such as communication bandwidth optimisation, coverage and fault tolerance are not usually considered in this context. The motivation behind this research is formulating and solving combined robot navigation issues (such as obstacle avoidance, environment mapping and coverage) with sensor network issues (such as congestion control, routing and node energy minimisation). In this paper we present several types of algorithms for Mobile Wireless Sensor Nodes (MWSN) as well as experimental results with a fleet of mobile robots and sensors in our lab. The algorithms include Adaptive Sampling (AS) for distributed field estimation, Potential Fields (PF) for communication bandwidth optimisation, and a Discrete Event Controller (DEC) for mission planning.
Serotonin-induced changes in membrane potential and cytosolic free calcium in a clonal pituitary cell line (AtT-20) of cultured mouse corticotropes

Abstract The effects of serotonin (5-HT) were examined on the cytosolic free calcium concentration, {Ca 2+ } i , in fura-2-loaded cells from a clonal cell line derived from the mouse anterior pituitary gland (AtT-20/D16v). Brief applications of 5-HT produced transient increases in {Ca 2+ } i . The duration andthe amplitude of the 5-HT-induced increase in {Ca 2+ } i depended on the duration of 5-HT application. Longer duration (150 msec) applications of 5-HT produced a transient increase followed by a prolonged plateau phase of {Ca 2+ } i . Oscillations in {Ca 2+ } i were initiated and maintained in previously quiescent corticotropes following brief exposures to 5-HT. Addition of cobalt (500 μM − 3.6 mM) to the extracellular solution abolished oscillations in {Ca 2+ } i and produced transient but not sustained increases in {Ca 2+ } i in response to 5-HT. Electrophysiological responses to 5-HT were recorded in separate experiments using the whole-cell patch clamp recording technique. Application of 5-HT to single cells produced a depolarization which was accompanied by a decrease in membrane conductance when measured under voltage clamp. The duration of the depolarizing response also increased with the duration of the 5-HT application. With longer duration 5-HT applications, the 5-HT-induced depolarizing response resembled the spontaneous action potential responses recorded in the same cell. However, the 5-HT-induced depolarizations were unaltered in the presence of extracellular cobalt. This suggests that the transient increase in {Ca 2+ } i recorded when 5-HT was applied in the presence of cobalt may represent intracellular release of calcium. These results demonstrate that 5-HT activates single cultured corticotropes directly by producing an increase in {Ca 2+ } i and cell depolarization.
Tacit knowledge and the effect of pattern configuration on mental scanning

Two opposing hypotheses are that estimated distances may be used to predict scanning times in mental scanning experiments (Mitchell & Richman, 1980; Pylyshyn, 1981) and that scanning times may be used to estimate distances on maps (Thorndyke, 1981). We tested these hypotheses by having people both estimate lengths and mentally scan diagonal lines, spirals, and mazes. There were large and consistent differences in the rate of scanning the three configurations, regardless of whether people scanned percepts or images. These differences could not be accounted for by differences in length estimates or by people’s tacit knowledge of their scanning rates. We propose that people actually do mental scanning in a mental scanning task rather than use length estimates to generate scanning time and that they do not rely on scanning times to estimate length in a length estimation task.
Was Reagan Really a Great Communicator? The Influence of Televised Addresses on Public Opinion

This article examines the influence that televised addresses have on the public's evaluation of the president. To do this it measures the influence of 10 of President Reagan's televised addresses from 1981 to 1984, using individual-level data gathered in national public opinion surveys. Although scholars and pundits universally acknowledged Reagan's prowess with televised addresses, this study finds, contrary to expectations, that Reagan's televised addresses had limited success in influencing the public's evaluation of him and his presidency. Given these results, this article examines what opportunities presidents who are not as rhetorically skilled as Reagan have in trying to influence public opinion with televised addresses. This study concludes that although presidents must be careful choosing when to deliver a televised address, televised addresses nevertheless remain a potentially useful tool in helping presidents accomplish their purposes.
LEED, Auger and plasmon studies of negative electron affinity on Si produced by the adsorption of Cs and O

Abstract We have made LEED, Auger, and Plasmon measurements to study how Cs and O adsorb onto the (100) surface of p-type degenerate Si to produce negative electron affinity (NEA). A key factor to producing NEA was found to be a highly ordered Si surface as reflected by very high quality 2×2 LEED patterns. When NEA is produced, both the adsorbed Cs and O give the same LEED pattern as the original Si surface, but with a general enhancement of the half-order spot intensity. The adsorption of both Cs and O is strongly self-limiting, apparently controlled by the number of available appropriate sites on the surface. If Cs and O adsorb amorphously, NEA is not achieved. The thermal desorption of Cs occurs over a fairly broad temperature range centered at about 550°C. After Cs desorbs, the remaining O reverts spontaneously from an ordered layer to an amorphous layer, and then desorbs at about 800°C with an activation energy of 3.3 eV. Measurements of backscattered electron energy losses due to plasmons have shown that the Si surface plasmon is reduced in energy from 12.5 V to 7.0 V by the Cs-O layer. From this, an effective dielectric constant e = 5.3 for this layer can be deduced which, in turn, enables us to characterize completely the Cs-O dipole layer. The geometrical model described by Levine for the NEA surface is consistent with our experimental results.
The meconium plug syndrome revisited

Abstract The intelligent management of newborn infants who have symptoms or signs of intestinal obstruction requires a familiarity with the meconium plug syndrome. Although recognized and described a decade ago, 1 this syndrome has not yet been widely discussed in the surgical and pediatric literature. Some questions arose at the time of the original report, particularly related to the etiology and the relationship of this type of obturant obstruction to meconium ileus associated with fibrocystic disease and to dyskinetic colonic function associated with congenital aganglionic megacolon. Although we have acquired little additional information regarding the etiology of the meconium plug syndrome, sufficient time has now elapsed to provide a greater body of experience for analysis and to bring to the reader's attention some of the problems that we have encountered in the management of this entity. For these reasons we propose to reconsider the meconium plug syndrome and to recount our experience with the nine originally reported infants and 21 additional patients treated at the Columbus Children's Hospital.
Peer substance use as a mediator between early pubertal timing and adolescent substance use: longitudinal associations and moderating effect of maltreatment.

Abstract Background Early pubertal timing has received considerable empirical support as a risk for adolescent substance use. However, few studies have examined the mediators linking these variables. Therefore, the aims of this study were (1) to examine peer substance use as a mediator between pubertal timing and adolescent substance use longitudinally and (2) to test gender and maltreatment experience as moderators of the mediational model. Methods Data were obtained from Time 1, 2, and 3 of a longitudinal study of maltreatment and development. At Time 1 the sample was comprised of 303 maltreated and 151 comparison children aged 9–13 years (213 females and 241 males). Longitudinal mediation was tested using structural equation modeling and moderating effects were tested using multiple group analysis. Results Peer substance use mediated the relationship between early pubertal timing and later adolescent substance use for the total sample. Moderation analyses indicated this significant indirect effect did not differ for males and females. However, it did differ for maltreated versus comparison adolescents with the mediational effect only remaining significant for the comparison group. Conclusions This is one of the first studies to examine peer substance use as a mediator of pubertal timing and adolescent substance use using a longitudinal design. Early maturing males are at equal risk to early maturing females for interacting with peers that may draw them into substance use. Additionally, the findings indicate that while peers are mediators for comparison adolescents a different mechanism may link early puberty to substance use for maltreated adolescents.
Laboratory characterization of hydromechanical properties of a seismogenic normal fault system

Abstract The Stillwater seismogenic normal fault in Dixie Valley, Nevada has been historically active and is located in an area of high heat flow and hydrothermal activity. Three primary structural elements are identified in the fault zone: a relatively wide fault core (with breccia pods embedded in cataclasites), a damage zone (with arrays of mesoscopic fractures), and protolith. Hydromechanical properties of representative core samples were characterized in the laboratory, and microstructural analyses were conducted using optical and scanning electron microscopy. When deformed in conventional triaxial compression, dilatancy and brittle fracture were observed in each sample. Samples from the core of the fault were relatively weak, with strengths similar to that of unconsolidated fault gouge, whereas granodiorite samples from the protolith were as weak as the core and damage zone samples were stronger. Permeability is dependent on effective pressure, porosity and connectivity of the pore space, with values ranging over four orders of magnitude among the core samples. The lowest permeability of 3×10 −20 m 2 was measured in a fault core sample with a microstructure indicative of implosion brecciation. In conjunction with field measurements, the laboratory data suggest that fluid flow and changes in fluid storage are concentrated in the damage zone, with permeability several orders of magnitude higher than the protolith and fault core. Permeability contrast (one order of magnitude) at the core sample scale exists between the cataclasite and implosion breccia in the fault core. Because of dilatancy and poor drainage in the breccia pods, anomalously low pore pressures may develop in localized clusters due to dilatancy hardening during the preseismic period. These clusters of low pore pressure can act similarly to fault jogs, locally inhibiting fault rupture and inducing brecciation when the delayed failure finally occurs by catastrophic implosion.
The Molecular Basis of Glycogen Storage Disease Type 1a: STRUCTURE AND FUNCTION ANALYSIS OF MUTATIONS IN GLUCOSE-6-PHOSPHATASE *

Glycogen storage disease type 1a is caused by a deficiency in glucose-6-phosphatase (G6Pase), a nine-helical endoplasmic reticulum transmembrane protein required for maintenance of glucose homeostasis. To date, 75 G6Pase mutations have been identified, including 48 mutations resulting in single-amino acid substitutions. However, only 19 missense mutations have been functionally characterized. Here, we report the results of structure and function studies of the 48 missense mutations and the ΔF327 codon deletion mutation, grouped as active site, helical, and nonhelical mutations. The 5 active site mutations and 22 of the 31 helical mutations completely abolished G6Pase activity, but only 5 of the 13 nonhelical mutants were devoid of activity. Whereas the active site and nonhelical mutants supported the synthesis of G6Pase protein in a manner similar to that of the wild-type enzyme, immunoblot analysis showed that the majority (64.5%) of helical mutations destabilized G6Pase. Furthermore, we show that degradation of both wild-type and mutant G6Pase is inhibited by lactacystin, a potent proteasome inhibitor. Taken together, we have generated a data base of residual G6Pase activity retained by G6Pase mutants, established the critical roles of transmembrane helices in the stability and activity of this phosphatase, and shown that G6Pase is a substrate for proteasome-mediated degradation.
Chronic alcohol administration stimulates nitric oxide formation in the rat liver with or without pretreatment by lipopolysaccharide.

This study examines the effect of chronic alcohol consumption on nitric oxide release from the liver of rats with or without lipopolysaccharide (LPS) (Escherichia coli) treatment. Reactive nitrogen intermediates (RNIs) in plasma were monitored with an NOx Analyzer, and nitric oxide (NO) production was measured as nitrite or nitrite + nitrate accumulation in perfusates of the perfused liver, and in supematants of the freshly isolated hepatic cells after incubation for 3 hr in Hank's balanced salt solution buffer containing 1 Mm l-arginine. RNI concentration in plasma of control rats was 32.0 ± 3.4 μm (mean ×se). Livers from diet-fed control rats produced RNIs at the barely detectable rate of 7.8 ± 1.5 nmol/hr × g wet liver. Six hr after administration of LPS (1 mg/kg, iv), plasma RNI levels in diet-fed control rats increased to 426.9 ± 29.4 μm, and RNI release from the perfused liver was also markedly elevated to 97.7 ± 7.7 nmol/hr × wet g liver, indicating hepatic NO release as a potentially important source for the increased RNI in plasma. The presence of NG-monomethyl-l-arginine (0.5–1 mm) or the absence of l-arginine in the perfusate inhibited LPS-induced stimulation of RNI release. EGTA (1 mm) had little effect, indicating that the increased RNI release was likely to be due to inducible NO synthase activity. The release of RNIs by freshly isolated Kupffer cells increased 13-fold, and this small cell mass contributed almost half of the hepatic RNI production under these conditions. Plasma ALT concentration was elevated after LPS administration, indicating incipient liver damage. Chronic alcohol administration resulted in increased RNI levels in plasma (44.6 ± 4.2) that were accompanied by increased spontaneous release in the perfused liver (16.4 ± 1.5 nmol/hr wet g). Enhanced activity of Kupffer cells was responsible for this increase. After administration of LPS, the increase in plasma RNIs (565.72 ± 49.6 μm) was slightly higher in chronic alcoholic rats than in control animals. This was also accompanied by a somewhat higher RNI release from the perfused liver (125.40 ± 12.2 nmol/hr × wet g) in the same group. Hepatocytes were responsible for the post-LPS increase in alcoholic rats. Plasma ALT concentration was higher in alcoholic than control, diet-fed rats after LPS, indicating more liver damage in that group. The exact role of the elevated hepatic RNI release in affecting hepatic function in chronic alcoholic animals remains to be clarified.
Reversals of noise induced flow

Abstract We consider diffusive motion on a periodic, anisotropic potential. Adding a zero-average force that fluctuates between three values: − F , 0 and + F , can bring about net flow. As the frequency of the fluctuations varies the direction of the flux can change. We discuss a possible application for the construction of a device to separate macromolecules.
Disclosure, Stress, and Support During Gender Transition on Facebook

Social computing technologies, such as social networking sites (SNSs), often privilege people who fit within expected, static categories. Thus, users embarking on major identity changes, such as gender transition, often encounter stress when using SNSs to interact with their online social networks. To address this problem and reflect on the design of SNSs and other social computing systems, we present the results of a comprehensive online survey of transgender and gender non-conforming SNS users. Our findings indicate that although Facebook can be a stressful place for gender transition due to difficulties of transition disclosure, support from one's Facebook network can help to mitigate some of this stress. We examine Facebook both as a site of stress and as a site of support. Better understanding the relationships between stress, disclosure, and support on SNSs for these particular users can inform technology design that will benefit people who struggle with navigating a wide range of major identity changes online.
A hierarchical approach for predicting the transport properties of the gramicidin A channel

A hierarchical computational approach combining results of molecular dynamics (MD) simulations with continuous Poisson–Nernst–Planck (PNP) theory was used to investigate ion transport in a gramicidin A (gA) channel embedded within a 1,2-dimyristoylphosphatidylcholine (DMPC) bilayer. Molecular dynamics (MD) employing the CHARMM force field was used to investigate the diffusion of Na+ and K+ at different locations along the gA channel in both singly- and doubly-occupied states. Self-diffusion coefficients for single Na+ and K+ cations were determined to be 4.7 × 10−7 cm2 s−1 and 6.2 × 10−7 cm2 s−1, respectively. Using these values, maximum ionic conductivities calculated from the Nernst–Einstein equation were 37 pS and 49 pS for Na+ and K+, respectively, in the singly-occupied gA channel. These values agree with experimental data within an order of magnitude. Conductance of the gA channel was calculated from simulation results using the three-dimensional Poisson–Nernst–Planck (3D-PNP) model. Partial charge distributions for gA and for DMPC were assigned using the Poisson–Boltzmann module available in CHARMM. Diffusion coefficients were those obtained from the MD simulation. Results confirm that DMPC electrostatics have significant influence on channel conductivity. At low electrolyte concentrations, the channel cannot be occupied by more than one monovalent cation. Using ion diffusion coefficients obtained at different locations along the channel, current–voltage values obtained using 3D-PNP predictions for a channel immersed in an aqueous NaCl solution show good agreement with experimental values.
Isolated thoracolumbar transverse process fractures: call physical therapy, not spine.

Background Historically, thoracolumbar spine transverse process fractures (TVPFx) found on "plain films" of the spine were occasionally associated with occult, mechanically significant vertebral fractures. Thus, "log-roll precautions" have been used pending formal spine evaluation and further imaging. As integrated helical computed tomography (CT) scans of the torso have become routine screening tools in high-energy trauma, TVPFx have been diagnosed with far greater frequency. Yet, where no associated spine injuries are found initially, such isolated TVPFx appear to be benign. Methods We retrospectively reviewed the diagnosis and management of TVPFx in a large Level I trauma center in the period between 2002 and 2005. Of 314 patients with TVPFx who survived more than 48 hours, 17% had fractures of the weight-bearing columns of the thoracolumbar spine noted on the same CT scan and were excluded from study. The management and outcome of the remaining "isolated" TVPFx were assessed by review of trauma registry and charted data. Results The 248 patients included sustained 2.3 +/- 1.5 (SD) TVPFx. They spent 29 hours +/- 32 hours on log-roll precautions while being evaluated by spine consultants and "cleared" before initiating physical therapy. Despite this prolonged immobilization and substantial further investigation, none of the patients with TVPFx judged to be isolated on the basis of screening truncal CT scan proved to have a missed injury of a major vertebral element on further study. Conclusions Isolated thoracolumbar TVPFx are found frequently when helical CT scan is used to screen the torso after high-energy injury. TVPFx are usually multiple. They can be markers for visceral injuries, and in this study, 17% were associated with "significant" fractures. TVPFx require careful pain management and benefit by early mobilization. Yet, where no other vertebral fracture is seen on an adequate screening CT scan, investigation may reasonably end. Further imaging and consultations with spine services waste scarce resources, and lead to prolonged log-roll precautions, which delay mobilization and are potentially deleterious to overall patient care.
Determination of Bitter Orange Alkaloids in Dietary Supplements Standard Reference Materials by Liquid Chromatography with Ultraviolet Absorbance and Fluorescence Detection

Four adrenergic amines [synephrine, octopamine, tyramine, and n-methyltyramine] were determined in a variety of Bitter Orange containing dietary supplements. Two extraction techniques were evaluated in detail: Soxhlet extraction and sonication extraction. A liquid chromatographic separation using a reversed-phase C(18) stationary phase and the ion-pairing reagent sodium dodecyl sulfate was developed to separate the Bitter Orange alkaloids. Ultraviolet absorbance detection at 220 nm and fluorescence detection with excitation at 273 nm and emission at 304 nm were used for the alkaloid detection. The method described was used for the assignment of the levels of the predominant alkaloids in three candidate standard reference materials containing Bitter Orange.
A High-Speed Direct-Coupled Magnetic Memory Sense Amplifier Employing Tunnel-Diode Discriminators

Because of a multiplicity of conflicting requirements, sense amplifier design is probably the most difficult circuit problem in a large, high-speed digital computer memory. The requirements include absence of pattern sensitivity, controllable input impedance, a wide band pass, stable gain, high common mode rejection, the ability to handle bipolar signals, stable reference levels, a fast comparator, low threshold level, and, one hopes, low cost. This paper discusses a new circuit which fulfills these requirements with simplicity. Intended for large size (> 1000 words) random access core and thin-film memories, it is capable of handling, for example, a 50-mv ``1'' with approximately 50-nsec delay for transmission and comparison. Common mode signals of as high as 10 volts do not affect discriminator performance. Two key features of the circuit are the use of a dc-coupled, ``long-tail pair'' preamplifier and a pair of tunnel diodes as the discrimination elements. The dc-coupled differential preamplifier provides high common mode rejection, stable gain, is pattern insensitive, and has the ability to handle bipolar signals. The tunnel diode provides a superior discriminator, since it is fast, and has a low-level threshold which is controllable and stable with temperature variations. Thus, requirements on the magnitude and stability of the preamplifier gain are less severe. Design equations are derived and a complete dc worst-case analysis is performed. Variations in the circuit for several specific applications and experimentally determined performance data are described. The generalized problem of a tunnel-diode discriminator used with a preamplifier is treated in Appendix II.
Estimating Risk of Low Radiation Doses - A Critical Review of the BEIR VII Report and its Use of the Linear No-Threshold (LNT) Hypothesis

This article explores the origin of the linear no-threshold (LNT) dose-response model and how it came to be used in cancer risk assessment worldwide. Following this historical appraisal is an evaluation of the LNT model, within the framework of the BEIR VII report of the National Academy of Sciences, on the health effects of ionizing radiation. The final section of this article provides an assessment of the LNT model's capacity to make accurate predictions of risk in the low-dose zone based on recent molecular mechanistic findings and epidemiological methods, with particular emphasis on the limitations of epidemiological studies to estimate risks in the low-dose zone.
Chronic stress, allostatic load, and aging in nonhuman primates

Allostatic load is the "wear and tear" of the body resulting from the repeated activation of compensatory physiological mechanisms in response to chronic stress. Allostatic load can significantly affect the aging process and result in reduced longevity, accelerated aging, and impaired health. Although low socioeconomic status is associated with high allostatic load during aging, the effects of status-related psychosocial stress on allostatic load are often confounded by lifestyle variables. Chronic psychosocial stress associated with low dominance rank in nonhuman primates represents an excellent animal model with which to investigate allostatic load and aging in humans. Research conducted with free-ranging rhesus monkeys suggests that female reproduction can also be a source of stress and allostatic load. Female reproduction is associated with increased risk of mortality and hyperactivation of the hypothalamic-pituitary-adrenal axis. Reproduction is especially stressful and costly for aging females of low rank. Although many indicators of body condition and neuroendocrine and immune function are influenced by aging, there are marked and stable individual differences among aging females in body condition, plasma cortisol responses to stress, and cytokine responses to stress. These differences are consistent with the hypothesis that there are strong differences in chronic stress among individuals, and that allostatic load resulting from chronic stress affects health during aging. Comparisons between captive and free-ranging rhesus monkey populations may allow us to understand how differences in environmental stress and allostatic load affect rates of aging, and how these in turn translate into differences in longevity and health.
The Thirty Meter Telescope (TMT): An International Observatory

The Thirty Meter Telescope (TMT) will be the first truly global ground-based optical/infrared observatory. It will initiate the era of extremely large (30-meter class) telescopes with diffraction limited performance from its vantage point in the northern hemisphere on Mauna Kea, Hawaii, USA. The astronomy communities of India, Canada, China, Japan and the USA are shaping its science goals, suite of instrumentation and the system design of the TMT observatory. With large and open Nasmyth-focus platforms for generations of science instruments, TMT will have the versatility and flexibility for its envisioned 50 years of forefront astronomy. The TMT design employs the filled-aperture finely-segmented primary mirror technology pioneered with the W.M. Keck 10-meter telescopes. With TMT’s 492 segments optically phased, and by employing laser guide star assisted multi-conjugate adaptive optics, TMT will achieve the full diffraction limited performance of its 30-meter aperture, enabling unprecedented wide field imaging and multi-object spectroscopy. The TMT project is a global effort of its partners with all partners contributing to the design, technology development, construction and scientific use of the observatory. TMT will extend astronomy with extremely large telescopes to all of its global communities.
SYMPOSIUM EDITOR'S COMMENTS LOCAL GOVERNMENT CAPACITY BUILDING

(1981). Symposium Editor’S Comments Local Government Capacity Building. Journal of Urban Affairs: Vol. 3, No. 1, pp. iv-v.
Light at the end of the tunnel: a Monte Carlo approach to computing value of information

Calculating the expected value of information (VOI) for sequences of observations under uncertainty is intractable, as branching trees of potential outcomes of sets of observations must be considered in the general case. We address the combinatorial challenge of computing ideal observational policies in situations where long sequences of weak evidential updates may have to be considered. We introduce and validate the use of Monte Carlo procedures for computing VOI with such long evidential sequences. We evaluate the procedure on a synthetic dataset and on a challenging citizen-science problem and demonstrate how it can effectively cut through the intractability of the combinatorial space.
The undertreatment of pain in ambulatory AIDS patients.

Abstract Pain is highly prevalent in individuals with HIV disease, yet is often overlooked as a symptom requiring clinical intervention. We evaluated the adequacy of analgesic management for pain and identified predictors of pain undertreatment in a sample of 366 ambulatory AIDS patients using a prospective cross-sectional survey design. Two hundred and twenty-six of the 366 ambulatory AIDS patients surveyed reported “persistent or frequent” pain over the 2 week period prior to the survey. Adequacy of analgesic therapy was assessed using the Pain Management Index (PMI - a measure derived from the Brief Pain Inventory) and the type and frequency of analgesic medications prescribed for pain. Results indicated that nearly 85% of patients were classified as receiving inadequate analgesic therapy based on the PMI. Less than 8% of the 110 patients who reported “severe” pain were prescribed a “strong” opioid (e.g., morphine), as suggested by published guidelines. Adjuvant analgesic drugs (e.g., antidepressant medications) were prescribed in only 10% of the patients. Women, less educated patients, and patients who reported injection drug use as their HIV transmission risk factor were most likely to have received inadequate analgesic therapy. These results demonstrate the alarming degree of undertreatment of pain in ambulatory patients with AIDS, and indicates the need to improve the management of AIDS-related pain in this underserved population. Future research should elucidate the factors that impede adequate pain management in order to overcome obstacles to adequate treatment.
Association and Division Membership among Small College Librarians

This study explores ALA membership among directors at small liberal arts colleges. Results show that directors at the smallest colleges are much less likely to be members of ALA and ACRL than their colleagues at larger colleges are. The study investigates trends based on the director’s level of completed education, the director’s tenure at her or his institution, and the relative size of the institutions. The discussion questions why directors at smaller colleges are less likely to be members of ALA and ACRL and examines how those associations might expand their services among these individuals.
Parent-Child Relationships During the Transition to Adulthood

This article uses a panel study of children and mothers to examine how parents and children conceptualize, perceive, and report on their relationships with each other during the children's transition to adulthood years. The article provides strong support for the reliability and validity of reports of parent-child relationships. The article documents generally positive and supportive relationships between parents and children, more positive relationships with mothers than with fathers, and an improvement in relationships as children mature from age 18 to 23. Further, parent-child relationships are perceived differently by parents and children in that there is not just one perception of the relationship between child and parent, but a relationship as perceived by the child and a relationship as perceived by the parent.
Attempts to Reach the Oldest and Frailest: Recruitment, Adherence, and Retention of Urban Elderly Persons to a Falls Reduction Exercise Program

PURPOSE OF THE STUDY: To assess the recruitment, adherence, and retention of urban elderly, predominantly African Americans to a falls reduction exercise program. DESIGN AND METHODS: The randomized controlled trial was designed as an intervention development pilot study. The goal was to develop a culturally sensitive intervention for elderly persons who suffered a fall and visited an emergency department (ED). Participants were taught exercises during 4 on-site group classes and encouraged to continue exercising at home for 12 weeks and attend additional on-site monthly classes. The protocol included a specifically designed intervention for increasing retention through trained community interventionists drawn from the participants' neighborhoods. RESULTS: The screening of 1,521 ED records after falling yielded the recruitment of 204 patients aged 65 years and older. Half were randomized into the falls prevention program. Of the 102 people in the intervention group, 92 completed the final 6-month assessment, 68 attended all on-site sessions, but only 1 reported exercising at home all 12 weeks. Those who lived alone were more likely (p = .03) and those with symptoms of depression were less likely (p = .05) to attend all on-site exercise classes. The final recruitment rate was estimated as 31.8%. The final retention rates were 90.2% and 87.3% for the intervention and control groups, respectively. IMPLICATIONS: Recruitment of frail elderly African American patients is resource intensive. Adherence to the on-site exercise classes was better than to the home-based component of the program. These findings have implications for the design of future community-based exercise programs and trials. Language: en
Sea-Floor Spreading at the Junction between Gorda Rise and Mendocino Ridge

A Quaternary deformation pattern revealed by new sub-bottom acoustic profiles supplements previous knowledge derived chiefly from magnetic and seismic evidence on the contemporary tectonics off northern California. An inferred age for the sedimentary cover along the axis of the southern part of Gorda Rise suggests that no volcanism has occurred along that part of the rise for more than 100,000 years. Sea-floor spreading at the rise crest has been accommodated by sinking of a keystone block that forms the floor of Escanaba Trough, the median valley of the rise. Differential movement between Pacific and American tectonic plates could have caused the deformation pattern, and during this movement, the displacement offshore beyond the northwest end of the San Andreas fault is inferred to have divided at Cape Mendocino between a fault along Mendocino Ridge and a fault segment that connects with the Blanco fault farther northwest.
Icosapent Ethyl for Treatment of Elevated Triglyceride Levels

Objectives: To review the pharmacology, pharmacokinetics, clinical trial data, adverse effects, and formulary considerations of icosapent ethyl for the treatment of high triglyceride (TG) levels. Data Sources: A literature search with keywords Vascepa, icosapent ethyl, AMR101, and eicosapentaenoic acid of articles up to July 2013, along with the package insert for Vascepa and current guidelines for hypertriglyceridemia. Study Selection/Data Extraction: Two phase-III, placebo-controlled, randomized, double-blind, 12-week clinical trials were included in this review: the MARINE trial and ANCHOR study. The MARINE trial consisted of mainly overweight Caucasian men with fasting TG ≥500 and ≤2000 mg/dL taking 4 g/day icosapent ethyl, 2 g/day, or placebo. The ANCHOR study consisted of mainly overweight Caucasians with type-2 diabetes mellitus on statin therapy, with fasting TG ≥200 and <500 mg/dL taking 4 g/day icosapent ethyl, 2 g/day, or placebo. Data Synthesis: The MARINE trial showed a placebo-corrected medi...
Quantifying sources of bias in National Healthcare Safety Network laboratory-identified Clostridium difficile infection rates.

Objective. To assess the effect of multiple sources of bias on state- and hospital-specific National Healthcare Safety Network (NHSN) laboratory-identified Clostridium difficile infection (CDI) rates. Design. Sensitivity analysis. Setting. A total of 124 New York hospitals in 2010. Methods. New York NHSN CDI events from audited hospitals were matched to New York hospital discharge billing records to obtain additional information on patient age, length of stay, and previous hospital discharges. “Corrected” hospital-onset (HO) CDI rates were calculated after (1) correcting inaccurate case reporting found during audits, (2) incorporating knowledge of laboratory results from outside hospitals, (3) excluding days when patients were not at risk from the denominator of the rates, and (4) adjusting for patient age. Data sets were simulated with each of these sources of bias reintroduced individually and combined. The simulated rates were compared with the corrected rates. Performance (ie, better, worse, or average compared with the state average) was categorized, and misclassification compared with the corrected data set was measured. Results. Counting days patients were not at risk in the denominator reduced the state HO rate by 45% and resulted in 8% misclassification. Age adjustment and reporting errors also shifted rates (7% and 6% misclassification, respectively). Conclusions. Changing the NHSN protocol to require reporting of age-stratified patient-days and adjusting for patient-days at risk would improve comparability of rates across hospitals. Further research is needed to validate the risk-adjustment model before these data should be used as hospital performance measures.