cssi/SciSciGPT-SciSciNet huggingface dataset:
Airborne water vapor DIAL system development

A differential absorption lidar (DIAL) system developed at NASA Langley Research Center for the remote measurement of atmospheric H2O and aerosols from an aircraft is briefly discussed. This DIAL system utilizes a Nd:YAG laser-pumped dye laser as the off-line transmitter and a narrowband, tunable Alexandrite laser as the on-line transmitter. A 1-m monochromator and a multipass absorption cell are used to position the on-line laser to the center of the H2O line. The receiver system has a 14-in. diameter, f/7 Celestron telescope to collect the backscattered laser light and focus in into the detector optics. Return signals are converted to electrical signals by the optical detector and are digitalized and stored on magnetic tape. The results of fligh tests of the system are shown.
Androgenic regulation of growth factor and growth factor receptor expression in the CWR22 model of prostatic adenocarcinoma.

The effects of androgen manipulation on epidermal growth factor (EGF) receptor, p185erbB-2 and transforming growth factor-a (TGF-a) levels were examined in prostatic adenocarcinoma. Male nude mice were inoculated with the CWR22 androgen-dependent human prostatic tumor or an androgenindependent (CWR22R) derivative. Mice with CWR22 tumors were castrated and subsequently killed at 3, 7, 21, 28 or 42 days post-castration. Other CWR22-bearing mice received s.c. testosterone pellets at 21 days post-castration and were killed 7 days later. EGF receptor, p185 erbB-2 and TGF-a levels were examined by immuno-histochemistry. Strong EGF receptor and p185erbB-2 immunostaining was detected in CWR22 tumors from intact controls. EGF receptor immunostaining decreased by 65% to 70% at 21 to 42 days postcastration. Testosterone treatment at 21 to 28 days postcastration resulted in a 2-fold increase in EGF receptor immunostaining. p185 erbB-2 immunostaining within CWR22 tumors did not decrease following castration and, in fact, was slightly increased at 7 days post-castration. The effects of castration on EGF receptor and p185 erbB-2 levels were confirmed by Western blot analysis. Fewer than 10% of CWR22 tumor cells demonstrated strong TGF-a immunostaining, and androgen manipulation did not effect TGF-a immunostaining. In contrast, 30% of androgen-independent CWR22R tumor cells were strongly immunostained for TGF-a. Our findings indicate that EGF receptor levels, but not p185 erbB-2 levels, are strongly dependent on testosterone in CWR22 tumors. The co-localization of TGF-a and the EGF receptor in CWR22R tumors suggests that these factors may constitute an autocrine pathway that regulates androgen-independent growth. Int. J. Cancer 82:424‐429, 1999. r 1999 Wiley-Liss, Inc.
Hydrothermal decarboxylation of unsaturated fatty acids over PtSnx/C catalysts

Abstract Decarboxylation of fatty acids is a path to fuel-range hydrocarbons from renewable plant and seed oils. Pt/C is an effective hydrothermal catalyst for decarboxylating saturated fatty acids without added hydrogen, but it has shown low selectivity and activity for decarboxylating unsaturated fatty acids, which are prevalent in plant oils from soy and algae. To develop better decarboxylation catalysts, we compared three different Sn containing alloys, Pt3Sn/C, PtSn/C, and PtSn3/C, to Pt/C by performing batch reactions in liquid water at 350 °C for two hours with stearic (C18:0), oleic (C18:1), and linoleic (C18:2) acids. Pt/C gave yields of 0.70 ± 0.05, 0.16 ± 0.03, and 0.083 ± 0.009 for the C17 alkane, but none of the direct decarboxylation products (i.e., C17 alkenes), for the oleic and linoleic acid feeds. Stearic acid was the major byproduct from the unsaturated fatty acids. In contrast, the PtSnx/C catalysts provided two to three times higher C17 alkane yields at identical conditions. Experiments in D2O showed that water molecules were a source of hydrogen for saturation of the fatty acids. These results show that PtSnx alloys give better performance than Pt alone for the hydrothermal conversion of renewable fatty acids to fuel range hydrocarbons.
Time-dependent modulation by estrogen of amphetamine-induced hyperactivity in male rats.

Abstract The effect of estradiol benzoate on the increase in activity induced by d-amphetamine (0.25 mg/kg) was studied in male rats. Both short latency and long latency effects were observed. Amphetamine-induced hyperactivity was increased 45 minutes after estradiol (50 μg/kg) administration, decreased one day later and again increased during the period 8–16 days after injection. At doses of 12.5 and 25 μg/kg, effects were smaller and not statistically significant, although they had a similar temporal pattern to the 50 μg/kg dose. The short-latency, presumably non-genomic, effect of EB was studied in more detail at 15, 30, 45 and 60 minutes after the administration of 50 μg/kg EB. An enhancement of the amphetamine-induced increase in locomotor activity reached its maximum 30 minutes after injection. The time factor was critical for the effects observed, and the results supported the view that estrogen may alter behavior mediated by dopaminergic pathways.
Two-photon absorption in aqueous micellar solutions.

Addition of the surfactant sodium dodecyl sulfate at concentrations above the critical micelle concentration increases the fluorescence quantum yield and the two-photon absorption cross-section of charged [2.2]paracyclophane chromophores containing pairs of D-π-D chromophores. The resulting spectra in the micellar solutions are very similar to those obtained for neutral isostructural analogues in toluene. The measured ηδ values are 1300 GM for 1C and 1920 GM for 2C, which are comparable or larger to those in toluene. These results highlight possible misleading interpretation of two-photon-induced emission for evaluating the concentration of labeled substrates used in two-photon microscopy and provide guidelines for designing molecular structures with optimized two-photon action cross-sections in water.
Role of cellular bioenergetics in smooth muscle cell proliferation induced by platelet-derived growth factor

Abnormal smooth muscle cell proliferation is a hallmark of vascular disease. Although growth factors are known to contribute to cell hyperplasia, the changes in metabolism associated with this response, particularly mitochondrial respiration, remain unclear. Given the increased energy requirements for proliferation, we hypothesized that PDGF (platelet-derived growth factor) would stimulate glycolysis and mitochondrial respiration and that this elevated bioenergetic capacity is required for smooth muscle cell hyperplasia. To test this hypothesis, cell proliferation, glycolytic flux and mitochondrial oxygen consumption were measured after treatment of primary rat aortic VSMCs (vascular smooth muscle cells) with PDGF. PDGF increased basal and maximal rates of glycolytic flux and mitochondrial oxygen consumption; enhancement of these bioenergetic pathways led to a substantial increase in the mitochondrial reserve capacity. Interventions with the PI3K (phosphoinositide 3-kinase) inhibitor LY-294002 or the glycolysis inhibitor 2-deoxy-D-glucose abrogated PDGF-stimulated proliferation and prevented augmentation of glycolysis and mitochondrial reserve capacity. Similarly, when L-glucose was substituted for D-glucose, PDGF-dependent proliferation was abolished, as were changes in glycolysis and mitochondrial respiration. Interestingly, LDH (lactate dehydrogenase) protein levels and activity were significantly increased after PDGF treatment. Moreover, substitution of L-lactate for D-glucose was sufficient to increase mitochondrial reserve capacity and cell proliferation after treatment with PDGF; these effects were inhibited by the LDH inhibitor oxamate. These results suggest that glycolysis, by providing substrates that enhance the mitochondrial reserve capacity, plays an essential role in PDGF-induced cell proliferation, underscoring the integrated metabolic response required for proliferation of VSMCs in the diseased vasculature.
Bandstructure engineering with a two-dimensional patterned quantum dot lattice

A semiconductor laser with active layer consisting of a patterned quantum dot lattice demonstrates evidence of miniband formation resulting from inter-dot coupling. Excited state lasing is thought to result from a phonon bottleneck-like effect.
Catechol-O-Methyltransferase Contributes to Genetic Susceptibility Shared Among Anxiety Spectrum Phenotypes

Background Catechol- O -methyltransferase (COMT) has been investigated for its possible role in a wide range of psychiatric phenotypes. In particular, several studies support association of this gene with panic disorder and other anxiety-related traits. Methods We examined the COMT gene for association with genetic risk across a range of anxiety spectrum phenotypes. We used multivariate structural equation modeling to select twin pairs scoring at the extremes of a latent genetic risk factor shared by neuroticism, several anxiety disorders, and major depression from a large population-based twin sample. With one member from each of these pairs, the resulting sample of 589 cases and 539 control subjects were entered into a two-stage association study in which genetic markers were screened in stage 1, the positive results of which were tested for replication in stage 2. Results The functional val158met polymorphism (rs4680) plus nine other single nucleotide polymorphism markers selected to capture the major allelic variation across the COMT locus were analyzed for differences between cases and control subjects. Although the val (G) allele of rs4680 showed marginally significant association in our combined stage 1 plus stage 2 sample, a high-risk haplotype of this allele with the A allele of rs165599 was significantly over-represented in cases ( p = 1.97e-5, odds ratio=1.95). This haplotype also predicted individual differences in neuroticism and risk for several anxiety disorders and major depression. Consistent with prior studies, our findings are female-specific. Conclusions Variations in the COMT gene contribute to genetic risk shared across a range of anxiety-related phenotypes.
Characterization of two quenchers of chlorophyll fluorescence with different midpoint oxidation-reduction potentials in chloroplasts.

Abstract The properties of two redox quenchers of chlorophyll fluorescence in chloroplasts at room temperature have been investigated. 1. (1) Redox titration of the fluorescence yield reveals two n = 1 components with E m 7.8 at −45 and −247 mV, accounting for approx. 70 and 30% of the total yield, respectively. 2. (2) Neutral red, a redox mediator often used at redox potentials below −300 mV, preferentially quenches the fluorescence controlled by the −247 mV component. Titrations using neutral red artifactually create an n = 2 quenching component with E m 7.8 = −375 mV. 3. (3) Analysis of fluorescence induction curves recorded at different redox potentials indicates that both the −45 and −247 mV components can be photochemically reduced. The reduction of the −247 mV component corresponds to a fast phase of the induction curve whilst the slower reduction of the −45 mV component accounts for the tail phase. 4. (4) The excitation spectra for the fluorescence controlled by the two quenchers show small differences in the ratio of chlorophyll a and b . 5. (5) Whereas the −247 mV component readily shows a 60 mV per pH unit dependency on solution pH, the ability of the −45 mV component to respond to pH change is restricted. 6. (6) Triton Photosystem II particles contain both quenchers but the −247 mV component accounts for approx. 70% of the fluorescence and the high component has an E m 7.8 of +48 mV. The relative merits of sequential and parallel models in explaining the presence of the two quenchers are considered.
Thiolation of starch and other polysaccharides

Thiolated starches with a degree of substitution of 0.01–0.6 were obtained by pyrolysis of starch dithiobis(thioformates) followed by saponification. The pyrolytic decomposition of dithiobis(thioformates) followed two pathways: (1) to thionocarbonate , carbon disulfide, and sulfur, and (2) to dithiocarbonate , carbonyl sulfide, and sulfur. Only the second pathway affords thiolation. Thiol groups were determined by Ellman's reagent, by sulfur analyses, and, following acetylation, by the ratio of O-acetyl versus S-acetyl absorption in nuclear magnetic resonance spectra. The poly-saccharides cellulose, dextran, and xylan were thiolated by the same procedure.
Endocrinology as Paradigm, Endocrinology as Authority

What I would like to talk about with you tonight is endocrinology as paradigm, and endocrinology as authority. What is the process by which the ideas in a science such as endocrinology change with time, and how best can new ideas develop? How do ideas in science influence society, aside from the obvious effect of technology? Two things inspired me to speak to you on this subject. The first is the influence which Thomas Kuhn’s extraordinary book on “Structure of Scientific Revolutions” had on me when I first read it 20 years ago. I believe it provides a framework within which we may view our own field with profit. The second is that in casting about for a subject to talk on tonight, I uncovered my programs of previous Endocrine Society meetings I have attended and apparently, for some reason, not discarded. I came up with the very first meeting I attended
High-content phenotypic screenings to identify inhibitors of Candida albicans biofilm formation and filamentation

Candida species represent the main cause of opportunistic fungal infections worldwide, and Candida albicans remains the most common etiological agent of candidiasis, now the third to fourth most common nosocomial infection. These infections are typically associated with high morbidity and mortality, mainly due to the limited efficacy of current antifungal drugs. In C. albicans, morphogenetic conversions between yeast and filamentous forms and biofilm formation represent two important biological processes that are intimately associated with the biology of this fungus and also play important roles during the pathogenesis of candidiasis. We have performed cell-based phenotypic screens using three different chemical libraries from the National Cancer Institute's Open Chemical Repository collection and identified several compounds with inhibitory activity against C. albicans biofilm formation and/or filamentation. These phenotype-based approaches represent a prosperous alternative to conventional genetics and genomics techniques to address experimentally challenging and complex biological phenomena, such as biofilm formation and filamentation, while at the same time opening new possibilities for the development of new antifungal agents.
CYP2E1 Overexpression in HepG2 Cells Induces Glutathione Synthesis by Transcriptional Activation of γ-Glutamylcysteine Synthetase

Induction of CYP2E1 (cytochrome P450 2E1) by ethanol appears to be one of the central pathways by which ethanol generates a state of oxidative stress. CYP2E1 is a loosely coupled enzyme; formation of reactive oxygen species occurs even in the absence of added substrate. GSH is critical for preserving the proper cellular redox balance and for its role as a cellular protectant. Since cells must maintain optimal GSH levels to cope with a variety of stresses, the goal of this study was to characterize the GSH homeostasis in human hepatocarcinoma cells (HepG2) that overexpress CYP2E1. This study was prompted by the finding that toxicity in CYP2E1-overexpressing cells was markedly enhanced after GSH depletion by buthionine sulfoximine treatment. CYP2E1-overexpressing cells showed a 40-50% increase in intracellular H(2)O(2); a 30% increase in total GSH levels; a 50% increase in the GSH synthesis rate; and a 2-fold increase in gamma-glutamylcysteine synthetase heavy subunit (GCS-HS) mRNA, the rate-limiting enzyme in GSH synthesis. This GCS-HS mRNA increase was due to increased synthesis since nuclear run-on assays showed increased transcription in CYP2E1-expressing cells, and the GCS-HS mRNA decay after actinomycin D treatment was similar in CYP2E1-expressing cells and empty vector-transfected cells. The facts that treatment with GSH ethyl ester almost completely prevented the increase in GCS-HS mRNA and decreased H(2)O(2) levels and that transient transfection with catalase (but not manganese-superoxide dismutase) produced a decrease in GCS-HS mRNA only in CYP2E1-expressing cells suggest a possible role for H(2)O(2) in the induction of GCS-HS gene transcription. In contrast to results with HepG2 cells expressing CYP2E1, no increase in GCS-HS mRNA was found with a HepG2 cell line engineered to express human cytochrome P450 3A4. In summary, CYP2E1 overexpression in HepG2 cells up-regulates the levels of reduced GSH by transcriptional activation of GCS-HS; this may reflect an adaptive mechanism to remove CYP2E1-derived oxidants such as H(2)O(2).
Spinal cord representation of the micturition reflex

The spinal cord origin and peripheral pathways of the sensory and motor nerves to the urinary bladder were delineated in the cat by stimulating the appropriate nerves near the urinary bladder and recording from the dorsal and ventral rootlets near the spinal cord. The parasympathetic preganglionic neurons originated in the sacral segments of the spinal cord and reached the bladder by way of the pelvic nerve. The preganglionic parasympathetic perikarya to the urinary bladder were distributed over a length of approximately 1.5 segments, centered near the junction of segments S-2 and S-3 in cats with a median arrangement of the lumbosacral plexus. Conduction velocities in preganglionic parasympathetic fibers to the bladder ranged from 46 to 2 M/sec with a mean maximal velocity of 18.2 M/sec. The major sympathetic pathway to the bladder was in the hypogastric nerve. Preganglionic sympathetic fibers originated in the lumbar spinal cord and traveled through the caudal mesenteric ganglion and hypogastric nerve to the urinary bladder. There were both ipsilateral and contralateral preganglionic and afferent fibers in this pathway. The preganglionic sympathetic neurons originated in segments L-2 and L-5. They were usually distributed over approximately 2 full segments centered near the junction of L-3 and L-4 in cats with a median arrangement of the lumbosacral plexus. Neurons involved in the micturition reflex may extend from the rostral end of the L-2 segment to the caudal end of the S-3 segment. The sympathetic preganglionic neurons were usually separated from the somatic and parasympathetic columns by segments L-5 to L-7.
An interpretive study of purposeful, mood self-regulating consumption: The consumption and mood framework

Although much research has been conducted on mood in relation to purchase behavior, relatively little has focused on how it functions in the actual use of products and services. There are also research gaps with respect to a more multidimensional and holistic understanding of mood and its self-regulatory processes. To address these issues, an interpretive study, applying written protocols, was conducted with 70 consumers. The results indicate support for an emergent theoretical framework, the consumption and mood framework (CMF), which consists of four dimensions: (1) products and services as consumption tools, (2) mood states, (3) processes of mood self-regulation, and (4) individual differences. Further thematic aspects of each dimension and linkages among them are also discussed. Based on these findings, implications that utilize the CMF are drawn for future research. © 1997 John Wiley & Sons, Inc.
Application of carbon isotope stratigraphy to late miocene shallow marine sediments, new zealand.

A district (0.5 per mil) carbon-13/carbon-12 isotopic shift in the light direction has been identified in a shallow marine sedimentary sequence of Late Miocene age at Blind River, New Zealand, and correlated with a similar shift in Late Miocene Deep Sea Drilling Project sequences throughout the Indo-Pacific. A dated piston core provides an age for the shift of 6.2 +- 0.1 million years. Correlations based on the carbon isotopic change require a revision of the previously established magnetostratigraphy at Blind River. The carbon shift at Blind River occurs between 6.2 and 6.3 +- 0.1 million years before present. A new chronology provides an age for the evolutionary first appearance datum of Globorotalia conomiozea at 6.1 +- 0.1 million years, the beginning of a distinct latest Miocene cooling event associated with the Kapitean stage at 6.2 +- 0.1 million years, and the beginning of a distinct shallowing of water depths at 6.1 +- 0.1 million years. The Miocene-Pliocene boundary as recognized in New Zealand is now dated at 5.3 +- 0.1 million years. Extension of carbon isotope stratigraphy to other shallow Late Miocene sequences should provide an important datum for international correlation of Late Miocene shallow and deep marine sequences.
Survival of mononuclear phagocytes depends on a lineage-specific growth factor that the differentiated cells selectively destroy

CSF-1 is a hemopoietic growth factor that specifically causes the proliferation and differentiation of mononuclear phagocytic cells. Receptors for CSF-1 occur exclusively on cells of the mononuclear phagocytic series (precursor leads to monoblast leads to promonocyte leads to monocyte leads to macrophage). Studies of the actions of CSF-1 on freshly explanted macrophages have been complicated by contamination of the primary cell isolates with CSF-1-producing cells and by the heterogeneity of the proliferative responses of individual macrophages. A method is described for the production of a highly purified and homogeneous population of adherent bone marrow-derived macrophages (BMMs) that are devoid of CSF-1-producing cells. The method may also be used to obtain nonadherent precursors of the mononuclear phagocytic series. Studies of CSF-1 action and degradation in cultures of BMMs have revealed several new findings. First, CSF-1 is required for both the survival (without proliferation) and the proliferation of BMMs. Second, CSF-1 is degraded by BMMs in a concentration-dependent manner, over the range of concentrations that stimulates both cell survival and proliferation. Third, the rate of CSF-1 degradation is saturable (or approximately 7 X 10(4) molecules per cell per hour) at CSF-1 concentrations that cause maximum proliferation (or approximately 0.4 nM). Under these conditions, BMMs are greatly enlarged and contain numerous phase-lucent vacuoles. Thus macrophages specifically require CSF-1 for both survival and proliferation, yet selectively and rapidly degrade it. This apparent dichotomy may have important implications for the role of CSF-1 in macrophage homeostasis in vivo.
Food Habits and Diet Selectivity of the Brown Bullhead

Abstract Food habits of the brown bullhead Ameiurus nebulosus were investigated in June and July 1994 in Perch Lake, Jefferson County, New York to determine feeding selectivity. Twenty-seven prey taxa were identified from 39 brown bullhead (total length, 29–330 mm). Chironomid larvae and pupae constituted the greatest portion of the diet by number of die young of the year brown bullhead (total length, 29–49 mm, N=10). The amphipod Hyalella sp. and chironomid larvae constituted the greatest portion of the diet by number of the juvenile/adults (total length, 115–330 mm, N=29). Diet selectivity of die juvenile/adult brown bullhead was evident based on positive Ivlev electivities for Hyalella sp. and chironomid larvae, and negative electivities for the gastropod Amnicola limosa and the ephemeropteran Caenis sp. Selective feeding was also suggested in die young of the year bullhead which had a high electivity for chironomid pupae. Our use of benthic invertebrate sampling methods provided similar estimates of t...
User models: the problem of disparity

A significant component of a user model in an information-seeking dialogue is the task-related plan motivating the information-seeker's queries. A number of researchers have modeled the plan inference process and used these models to design more robust natural language interfaces. However in each case, it has been assumed that the system's context model and the plan under construction by the information-seeker are never at variance. This paper addresses the problem of disparate plans. It presents a four phase approach and argues that handling disparate plans requires an enriched context model. This model must permit the addition of components suggested by the information seeker but not fully supported by the system's domain knowledge, and must differentiate among its components according to the kind of support accorded each component as a correct part of the information-seeker's overall plan. It is shown how a component's support should affect the system's hypothesis about the source of error once plan disparity is suggested.
Primary mucinous adenocarcinoma of the scalp: A case report and literature review

Abstract Introduction Primary mucinous adenocarcinoma or mucinous eccrine carcinoma of the skin is a rare malignant neoplasm showing predilection to the head and neck. Distinguishing between these primary neoplasms and the more frequent metastatic mucinous deposits on the skin from primaries in the breast and gastrointestinal tract constitutes a diagnostic dilemma. Presentation of case We report a case of a 61-year-old lady who presented with a slow-growing, painless scalp nodule. Upon excision, it was diagnosed as “primary mucinous adenocarcinoma”. An extensive work-up in search for another primary tumour failed to show a primary malignancy elsewhere and the diagnosis of a primary eccrine mucinous adenocarcinoma of the skin was rendered. Discussion A review of the literature on this entity is presented, discussing diagnostic challenges and therapeutic options that of interest to surgeons, pathologists and dermatologists. Conclusion These tumours are indolent and low-grade, with a tendency for local, sometimes multiple, recurrences. Proper patient counselling and follow-up are important in treatment. Sound collaboration between clinicians and pathologists, for good therapeutic results, is of utmost importance.
shRNA silencing of AS3MT expression minimizes arsenic methylation capacity of HepG2 cells

Several methyltransferases have been shown to catalyze the oxidative methylation of inorganic arsenic (iAs) in mammalian species. However, the relative contributions of these enzymes to the overall capacity of cells to methylate iAs have not been characterized. Arsenic (+3 oxidation state) methyltransferase (AS3MT) that is expressed in rat and human hepatocytes catalyzes the conversion of iAs, yielding methylated metabolites that contain arsenic in +3 or +5 oxidation states. This study used short hairpin RNA (shRNA) to knock down AS3MT expression in human hepatocellular carcinoma (HepG2) cells. In a stable clonal HepG2/A cell line, AS3MT mRNA and protein levels were reduced by 83 and 88%, respectively. In comparison, the capacity to methylate iAs decreased only by 70%. These data suggest that AS3MT is the major enzyme in this pathway, although an AS3MT-independent process may contribute to iAs methylation in human hepatic cells.
Vibrational and Acoustical Analysis of Trussed Railroad Bridge Under Moving Loads

A Finite Element model has been developed for a Pratt truss railroad bridge located at Ft. Leonard Wood, MO. This model was used to investigate the vibration responses of a bridge under vehicle loading. Modeling results have been obtained for a single axle with two wheels traversing the bridge at different speeds. The current model does not include the effects of vehicle suspension. Superposition of multiple axles has been used to represent a locomotive transiting the bridge. The output of the vibration response was used as an input to an acoustic FE model to determine which vibrational modes radiate infrasound. The vibration and acoustic models of the railroad bridge will be reviewed, and results from the analysis will be presented. Measurements from an accelerometer mounted on the bridge agree reasonably well with model results. Infrasound could potentially be used to remotely provide information on the capacity and number of the vehicles traversing the bridge and to monitor the bridge for significant structural damage.Copyright © 2012 by ASME
Choice of purchasing arrangements in insurance markets

A simple dynamic model helps explain why risk-pooling purchasing arrangements evolved for health, disability, and term life insurance but not for property, automobile, or homeowners' insurance, and why whole-life policies typify life insurance purchased on an individual basis. We show that risk-pooling purchases facilitate insurance against unpredictable changes in one's risk type, but such contracts prevail in competitive equilibrium only when the loss probabilities increase with age, as they do for health, disability, and life insurance. In contrast, when the loss probability declines with age (as it does for automobile insurance), then competitive equilibrium entails separating insurance contracts.
The increasingly complex mechanism of HMG-CoA reductase.

HMG-CoA reductase (HMGR) is the target of statins, cholesterol-lowering drugs prescribed to millions of patients worldwide. More recent research indicates that HMGR could be a useful target in the development of antimicrobial agents. Over the last seven decades, researchers have proposed a series of increasingly complex reaction mechanisms for this biomedically important enzyme.The maturation of the mechanistic proposals for HMGR have paralleled advances in a diverse set of research areas, such as molecular biology and computational chemistry. Thus, the development of the HMGR mechanism provides a useful case study for following the advances in state-of-the-art methods in enzyme mechanism research. Similarly, the questions raised by these mechanism proposals reflect the limitations of the methods used to develop them.The mechanism of HMGR, a four-electron oxidoreductase, is unique and far more complex than originally thought. The reaction contains multiple chemical steps, coupled to large-scale domain mot...
Estimating a Finite Population Mean from Unequal Probability Samples

Abstract Two approaches to estimating a finite population mean from unequal probability samples are contrasted. In the prediction approach a model is specified for the population values and is used to predict the nonsampled values. In the generalized regression approach the Horvitz-Thompson estimator of the population mean is modified to allow the introduction of covariate information (Sarndal 1980). Generalized regression estimates have the desirable property of asymptotic design consistency, which is not always enjoyed by estimates in the prediction class. However, it is suggested that the prediction approach is the more principled method of estimation. If asymptotic design consistency is a desirable property in a given application, then only models that yield asymptotically design-consistent prediction estimates should be used. Two classes of models with this property are suggested, namely fixed and random-effects models that allow a separate intercept for subclasses of the population indexed by the pr...
Cognitive Group Therapy and Aerobic Exercise in the Treatment of Anxiety

Abstract Our purpose was to examine the effects of cognitive group therapy, aerobic exercise, or their combination on anxiety reduction. Seventy participants were divided into four groups: cognitive group therapy, aerobic exercise, both treatments, or control. Participants were administered the State-Trait Anxiety Inventory (STAI) before and after the study, and at a two-month follow-up. Results indicate that all interventions were equally effective in reducing anxiety as compared to no intervention. The combination of cognitive group therapy and exercise was not significantly more effective than either cognitive group therapy or aerobic exercise alone. Although effects were not maintained after two months, it is unclear whether this is attributable to the limitations of such interventions in changing more enduring traits. Possible mechanisms for change are discussed.
Lognormal distribution of inner continental shelf widths and slopes

Abstract Width of the inner continental shelf (distance from shore to 200-ft depth contour) was measured at 2, 136 stations located at 50-mile intervals along the coasts of the world. Inasmuch as most coastal areas have lognormal frequency distributions of inner shelf width, a logarithmic grade scale—‘inner shelf width grade scale’—was developed to compare coastal areas statistically. In order to further simplify statistical computations involving this scale, width measurements are transformed logarithmically to ‘delta units’ that give equal numeric significance to class intervals on the scale. This transformation involves the substitution: σ = log 2 ν 10 where μ is the numerical value of the inner shelf width in nautical miles.
Depth distribution and migration of helium in vanadium at elevated temperatures

Abstract The depth profiles and retention behavior of 4He implanted at 80 keV into vanadium have been investigated in cold rolled bulk and foil samples. The specimens were implanted at temperatures of 100, 400, and 800° C and at fluences up to 1 × 1018He/cm2. Helium depth distributions were found to be Gaussian for the 100° C implants but exhibited a double peak appearance for some of the highest fluence 400° C and 800° C implants. In polished samples blistering and flaking occurred at both 100° C and 400° C implant temperatures for fluences greater than 5 × 1017He/cm2, but little of the implanted helium appeared to have been released at a result of the exfoliation. Conversely, most of the implanted helium was released from 800 C implant areas though no significant blistering or surface perforation was observed. Blistering was observed to occur only on polished samples, through the release behavior was similar to that of the unpolished specimens on which no blistering was observed at any temperature or fluence. The surface condition of samples polished by different techniques was found to exert an influence on the temperature dependence of release and on the character of the blister topography.
Morphology of Langmuir-Blodgett multilayers: A near-total external fluorescence and reflectivity study.

X-ray reflection and near-total external fluorescence (NTEF) of Langmuir-Blodgett multilayers of stearate salt were found to be in significant disagreement with a simple-layered structure. The different samples contained one foreign Mn stearate double layer deposited at a different predefined depth for each sample. A binary model of voids accumulated in successive layers is proposed. The lacunar structure for the multilayer that originates with this model fits our reflectivity and NTEF results remarkably well and resolves long-standing discrepancies between optical and x-ray measurements.
The uselessness of the Fast Gauss Transform for summing Gaussian radial basis function series

The Fast Gauss Transform is an algorithm for summing a series of Gaussians which is sometimes much faster than direct summation. Gaussian series in d dimensions are of the form @?"j"="1^[email protected]"jexp(-[@a/h]^[email protected]?x-x"[email protected]?^2) where the x"j are the centers, h is the average separation between centers and @a is the relative inverse width parameter. We show that the speed-up of the Fast Gauss Transform is bounded by a factor @W(@a). When @[email protected]?1, @W can be large. However, when applied to Gaussian radial basis function interpolation, it is difficult to apply the Gaussian basis in this parameter range because the interpolation matrix is exponentially ill-conditioned: the condition number @k~(1/2)[email protected]^[email protected]^2 for a uniform, one-dimensional grid, and larger still in two dimensions or when the grid is irregular. Furthermore, the Gaussian RBF interpolant is ill-conditioned for most series in the sense that the interpolant is the small difference of terms with exponentially large coefficients. Fornberg and Piret developed a ''QR-basis'' that ameliorates this difficulty for approximations on the surface of a sphere, but because the recombined basis functions are perturbed spherical harmonics, not Gaussians, the Fast Gauss Transform is no longer applicable. The solution of the interpolation matrix system by a preconditioned iteration is less sensitive to condition numbers than direct methods because iterations are self-correcting and also because the preconditioning reduces the spread of the eigenvalues. However, each iteration requires a matrix-vector multiply which is fast only if this operation can be performed by some species of Fast Summation. When @a~O(1), alas, we show that @W is not large and the Fast Gauss Transform is not accelerative. Gaussian RBFs are unusual among RBF species through the absence of long-range interactions due to the exponential decay of the Gaussians with distance from their centers; many other RBF species do have long-range interactions, and it is well-established that these can be accelerated by fast multipole and treecode algorithms. We offer a less rigorous scale analysis argument to explain why the underlying difficulty in accelerating short-range interactions is not peculiar to the Gaussian RBF basis or to the Fast Gauss Transform, but rather is likely to be a generic difficulty in accelerating the short-range interactions of almost any RBF basis with almost any Fast Summation.
Active 3-D microscaffold system with fluid perfusion for culturing in vitro neuronal networks.

This work demonstrated the design, fabrication, packaging, and characterization of an active microscaffold system with fluid perfusion/nutrient delivery functionalities for culturing in vitro neuronal networks from dissociated hippocampal rat pup neurons. The active microscaffold consisted of an 8 × 8 array of hollow, microfabricated, SU-8 towers (1.0 mm or 1.5 mm in height), with integrated, horizontal, SU-8 cross-members that connect adjacent towers, thus forming a 3-D grid that is conducive to branching, growth, and increased network formation of dissociated hippocampal neurons. Each microtower in the microscaffold system contained a hollow channel and multiple fluid ports for media delivery and perfusion of nutrients to the in vitro neuronal network growing within the microscaffold system. Additionally, there were two exposed Au electrodes on the outer wall of each microtower at varying heights (with insulated leads running within the microtower walls), which will later allow for integration of electrical stimulation/recording functionalities into the active microscaffold system. However, characterization of the stimulation/recording electrodes was not included in the scope of this paper. Design, fabrication, fluid packaging, and characterization of the active microscaffold system were performed. Furthermore, use of the active microscaffold system was demonstrated by culturing primary hippocampal embryonic rat pup neurons, and characterizing cell viability within the microscaffold system.
Utilization of central nervous system resources for preparation and performance of complex walking tasks in older adults.

Introduction Walking in the home and community often involves performance of complex walking tasks. Understanding the control of such tasks is crucial to preserving independence and quality of life in older adults. However, very little research has been conducted in this area. Here we assess the extent to which two measures of central nervous system (CNS) activity are responsive to the challenges posed by preparation and performance of complex walking tasks. Prefrontal cortical activity was measured by functional near infrared spectroscopy (fNIRS) and sympathetic nervous system arousal was measured by skin conductance level (SCL). Materials and Methods Sixteen older men and women (age 77.2 ± 5.6 years) with mild mobility deficits participated in this study. Participants walked at their preferred speed without distractions along an unobstructed, well-lit course (control task) and also walked on the same course under five separate challenging conditions: performing a cognitive verbal fluency task (verbal task), dim lighting (dim task), carrying a tray (carry task), negotiating obstacles (obstacles task) and wearing a weighted vest (vest task). Mean prefrontal activation and SCL were calculated during the preparation and performance phases of each task. Gait spatiotemporal measurements were acquired by an instrumented gait mat. Results Prefrontal cortical activity and SCL were elevated during the preparation phase of complex walking tasks relative to the control task. During the performance phase, prefrontal activity remained elevated to a similar level as during task preparation. In contrast, SCL continued to increase beyond the level observed during task preparation. A larger increase in prefrontal activity was found to be linked to preserved quality of gait during complex walking tasks. Discussion These findings indicate that availability and utilization of CNS resources are important for optimizing performance of complex walking tasks in older adults.
Experimental comparison of robotics locomotion with passive tether and active tether

Most small robots require a tethered connection with a power and control source. The tether has advantages, namely robust communication and safe recovery, and disadvantages, tangling with obstacles and rough terrain. Active tether is a new research area for tethered robot systems. It provides continuously distributed form of actuation for robots that results from the effect of water hammer. It also reduces the friction of the tether by the jerks from the water hammer effect. In this paper, we duplicate the active tethered system and test the performance of the active tethered system by comparing it with passive tethered system under our test conditions for mobile robot. The two experimental comparison tests are distance test and drag test, which all show the advantage of the active tethered system. Furthermore, we address the broad impact of this novel form of locomotion.
Relative chemical stability of inorganically conjugated astaxanthin

Abstract 1. 1. Earlier studies had revealed the firmly bonded chemical association of astaxanthin, presumably as a kind of complex salt or ester, with calcium and (bi)carbonate in pigmented aragonitic skeletons of certain hydrocorals. 2. 2. Whereas astaxanthin, like other carotenoids, is readily bleached through atmospheric oxidation, notably when dissolved in organic solvents and exposed to light, a sol of astaxanthin soap, generated by dissolution of the purple skeleton of the hydrocoral Allopora californica in aqueous Na2EDTA solution, still maintained its lavender colour and unmodified astaxanthin content after the elapse of a period exceeding five years, standing in a room daily exposed to diffused natural lighting.
Association of cartilage degeneration with four year weight gain--3T MRI data from the Osteoarthritis Initiative.

Summary Objective To determine the effect of weight gain on progression of early knee morphologic abnormalities using magnetic resonance imaging (MRI) in a longitudinal study over 48 months. Design We studied the right knee of 100 subjects from the Osteoarthritis Initiative (OAI), selecting subjects aged ≥45 with osteoarthritis (OA) risk factors who demonstrated weight gain (minimum 5% increase in body mass index, BMI, n = 50) or no change in weight (BMI change Results The odds of worsening maximum cartilage (11.3, 95%, CI 3.5–51.4) and meniscal WORMS (4.5, 95% CI 1.4–17.3) were significantly greater in the weight gain group compared to the no change group, in addition to the odds of worsening cartilage defects at the patella and average meniscal WORMS ( P P Conclusion Our study demonstrated that weight gain is strongly associated with increased progression of cartilage degeneration in middle-aged individuals with risk factors for OA.
Maintaining convex interface shapes during electrodynamic gradient freeze growth of cadmium zinc telluride using a dynamic, bell-curve furnace profile

Abstract A novel, bell-curve furnace temperature profile is presented and predicted to achieve macroscopically convex solid–liquid interface shapes during melt growth of CZT in an EDG furnace. A strategy is also presented to dynamically adapt this furnace profile so that uniform, convex interface shapes are maintained through an entire growth run. This approach represents a significant advance over traditional gradient-freeze profiles, which always yield concave interface shapes, and static heat transfer designs, such as pedestal design, that achieve convex interfaces over only a small portion of the growth run. Importantly, this strategy may be applied to any Bridgman configuration that utilizes multiple, controllable heating zones. Realizing a convex solidification interface via this adaptive bell-curve furnace profile is postulated to result in better crystallinity and higher yields than conventional CZT growth techniques.
Zfp-37, a new murine zinc finger encoding gene, is expressed in a developmentally regulated pattern in the male germ line

To begin to examine the function in the mouse testis of genes containing the zinc finger motif, we have screened an adult mouse total testis cDNA library with probes to a conserved region of zinc fingers. We have isolated cDNAs for a new murine zinc finger encoding gene that has been designated Zfp-37. Northern blot hybridization analysis revealed Zfp-37 transcripts at high levels in the testis, the only adult tissue in which Zfp-37 expression was observed. Zfp-37 was also expressed at lower levels in the mid-gestation embryo and placenta. The major testicular transcripts are 2.3 and 2.6 kb. A 4.0 kb transcript was detected at lower levels in the testis as well as in embryo and placenta. Northern blot and in situ hybridization analysis revealed that expression of Zfp-37 was most abundant in germ cells which have completed meiosis and are undergoing the complex morphogenetic changes of spermiogenesis. The pattern of expression of Zfp-37 and the presence of the zinc finger domain suggest that Zfp-37 may have a role in regulating spermiogenesis.