cssi/SciSciGPT-SciSciNet huggingface dataset:
Stimulation of cytosolic free calcium and inositol phosphates by prostaglandins in cultured rat mesangial cells.

Abstract We studied the effects of four products of arachidonate cyclo-oxygenation on a phospholipase C-dependent signal transduction system in cultured rat glomerular mesangial cells. PGF 2α , PGE 2 and the thromboxane A 2 /endoperoxide analogue U-46619 rapidly increased cytosolic free Ca 2+ , measured in monolayers loaded with the fluorescent intracellular probe fura-2. Peak responses were dose-dependent and unaffected by chelation of extracellular Ca 2+ , indicating release from internal stores. The thromboxane A 2 -receptor antagonist SQ 27,427 selectively inhibited responses to U-46619. The PGI 2 analogue Iloprost had no effect on cytosolic Ca 2+ . PGF 2α , PGE 2 and U-46619 also stimulated accumulation of total inositol phosphates during 15 min incubations. We conclude that phospholipase C activation mediates the effects of certain eicosanoids on the glomerular mesangium.
The quiet gray whale (Eschrichtius glaucus)

Abstract Studies conducted during the period December 22, 1964–March 7, 1965 near San Diego, California and at several locations in Baja California failed to confirm the use of acoustic signals by the gray whale. It is concluded that this cetacean rarely transmits subsurface sounds, and that it utilizes methods other than echolocation for navigation in shallower areas during the day.
Effects of Parental Age on Offspring from Isolated Pairs of the Mealworm Tenebrio molitor

Tracey (1058) and Ludwig and Fiore (1960) found that at 25° and 20° C. larvae of the mealworm, Tenebrio molitor Linn., from young parents grew at a slower rate, required a significantly longer time to complete development, and had more molts than those from old parents. At these temperatures, an increase in parental age resulted in a decrease in the duration of adult life. Ludwig and Fiore (1960) observed that the shortening of the larval period and the reduction in the number of larval molts associated with an increase in parental age were not evident until the parents had aged at least 4 weeks, and the shortening of the adult stage until they had aged 6 weeks or longer.
Leveraging Pull Forces for the Future of HR

The ProblemWork has rapidly changed over the decades forcing the field to address the notion of pull issues and what these forces demand of HRD.The SolutionThis preface article introduces the notio...
Subset Selection Problems for Variances with Applications to Regression Analysis

Abstract This article presents a subset selection procedure for correlated variances with emphasis on the asymptotic case. An application to selecting the best set of independent variables in a regression problem is given.
Abstract 5716: Interference with repair of sub-lethal radiation damage by ABT-888, an inhibitor of poly(ADP-ribose) polymerase (PARP), and theobromine

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL BACKGROUND: Upon DNA damage, PARP-1 and -2 use NAD to build a polymer of ADP-ribose on themselves, histones, and other proteins, altering chromatin and recruiting repair complexes to the damage. Inhibition of PARP activity sensitizes cancer cells or tumor xenografts to radiation therapy (RT) and inhibits DNA repair. RT is usually delivered as fractionated daily doses, allowing sub-lethal damage (SLD) to be repaired between doses. We asked if ABT-888, a specific PARP inhibitor, or theobromine (TB), which radiosensitizes via a PARP-independent mechanism, could inhibit SLD repair. METHODS: Human lung cancer cells A549 and H460 were plated at a range of cell densities, exposed to Cs-137 γ-radiation (0-8 Gy), as single doses or as multiples of 2 Gy/day, with or without drugs, then allowed to form colonies. DNA double-strand breaks (DSB) were estimated as γH2AX foci. RESULTS: In agreement with literature data, 2.5 μM ABT-888 produced a dose enhancement factor (DEF) of 1.4 at 10% survival for single radiation doses, and 10 μM was only modestly better (DEF 1.5). A549 cells showed marked repair of SLD (Table), such that the surviving fraction (SF) after 6 Gy was lower (0.13) than for 3 x 2 Gy (0.52). When ABT-888 or TB was added 1 h before the first irradiation, cells were sensitized to 6 Gy single dose or 3 x 2 Gy. The combination was more effective. ABT-888-sensitized cells responded to 3 x 2 Gy with similar killing as unsensitized cells to a single 6 Gy dose (p = 0.93). The combined effects are reflected in a decrease in mean inactivation dose (MID). Higher levels of γH2AX foci in drug-treated cells indicate inhibition of damage processing. CONCLUSIONS: Radiosensitization of human lung cancer cells by ABT-888 is at least partially via inhibition of SLD repair. Although more ABT-888 produces little additional benefit, addition of TB, which acts through a complementary mechanism, further improves the response. ![Figure][1] Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5716. doi:1538-7445.AM2012-5716 [1]: pending:yes
Abstract 852: Novel role and mechanism of the LDHA protein as a survival factor for cancer cells.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Rationale: Lactate dehydrogenase A (LDHA), which catalyzes the conversion of pyruvate to lactate, serves as a poor prognostic serum marker for many different types of human cancers; however, it is not known whether this is simply the result of LDHA being released from dying cancer cells in patients with high tumor burden or whether LDHA could also be a signaling molecule that portends poor clinical outcome. Based on the observation that extracellular LDHA was identified as the key survival factor for cardiomyocytes exposed to oxidative stress, we sought to determine whether extracellular LDHA can act as a cancer cell survival factor and hence contributes to poor clinical outcome. We reasoned that LDHA released from the damaged cells could activate intracellular signaling pathways in surrounding tumor cells by means of membrane receptors, ultimately protecting those surrounding tumor cells from oxidative stress-induced cell death. Methods: To investigate our hypothesis, recombinant LDHA and its isoform LDHB was produced by transforming E. coli strain BL21(DE3) with pET-SUMO expression vector (Clontech) containing full-length human LDHA or LDHB cDNA. The resulting recombinant proteins were purified using TALON Metal Affinity Resin and used for 16h pre-treatment of Ramos human Burkitt's lymphoma and A6L human pancreatic cancer cells cultured in full serum containing medium. The amount of recombinant proteins relative to serum albumin is estimated to be less 1% and hence any effects of LDHA could not be simply due to non-specific protein concentration effect. Following the pre-treatment procedure, these cancer cells were subjected to oxidative stress induced by hydrogen peroxide (H2O2) at 100 μM for 24h. Cells were then counted in a hemacytometer using trypan blue dye to exclude dead cells. Results: We observed that while LDHB had no effect on cell death induced by H2O2 as compared to the non-pretreatment group, LDHA can act as a protective factor against oxidative stress induced by H2O2, and ultimately cell death. We also investigated the mechanism involved in the protective role of LDHA by using recombinant LDHA as a molecular probe against membrane proteins that were extracted from cancer cells. Conclusion: Our study defines the novel role and mechanism of LDHA protein as a survival factor in cancer cells, in addition to its enzymatic activity, which may explain the prognostic significance of extracellular LDHA. Furthermore, this study can lead to the identification of new membrane receptor(s) for LDHA which may provide new targets for cancer therapy. Citation Format: Brad Poore, Joshua Kee Park, Iman Afif, Laura Shingleton, Chi Van Dang, Anne Le. Novel role and mechanism of the LDHA protein as a survival factor for cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 852. doi:10.1158/1538-7445.AM2013-852
Bionanoelectronics with 1D materials

Rapid progress in materials science and electrical engineering has led to the development of miniature electronic platforms that have devices and components as small as the main components of live cells. These developments open up an exciting possibility of building integrated systems in which electronic and biological components function side-by-side. However, to realize this vision of bionanoelectronics, researchers need to overcome a number of challenges ranging from materials incompatibility to drastically different operation modes. Fortunately, recent developments in biosensing, and device-level and tissue-level integration with nanomaterials have started to address these challenges.
The utility of 11C-arachidonate PET to study in vivo dopaminergic neurotransmission in humans

We developed a novel method to study dopaminergic neurotransmission using positron emission tomography (PET) with [1-11C]arachidonic acid ([1-11C]AA). Previous preclinical studies have shown the utility of [1-11C]AA as a marker of signal transduction coupled to cytosolic phospholipase A2 (cPLA2). Using [1-11C]AA and [15O]water PET, we measured regional incorporation coefficients K* for AA and regional cerebral blood flow (rCBF), respectively, in healthy male volunteers given the D1/D2 agonist (10 or 20 μg/kg subcutaneous) apomorphine. We confirmed a robust central dopaminergic response to apomorphine by observing significant increases in the serum concentration of growth hormone. We observed significant increases, as well as decreases in K* and increases in rCBF in response to apomorphine. These changes remained significant after covarying for handedness and apomorphine dosage. The magnitude of increases in K* was lower than those in our previous animal experiments, likely reflecting the smaller dose of apomorphine used in the current human study. Changes in K* may reflect neuronal signaling downstream of activated D2-like receptors coupled to cPLA2. Changes in rCBF are consistent with previous studies showing net functional effects of D1/D2 activation. [1-11C]AA PET may be useful for studying disturbances of dopaminergic neurotransmission in conditions such as Parkinson's disease and schizophrenia.
The Freudian subject and the Maoist mind: the diaries of Hermine Hug-Hellmuth and Lei Feng.

Although written in vastly different cultural contexts and periods, Hermine Hug-Hellmuth's Diary of a Young Girl (1919) and Lei Feng's The Diary of Lei Feng (1963) both to a large extent were written as concept pieces, with the goal of illustrating specific theories of the self. In the case of Hug-Hellmuth, the underlying theory is the Freudian sexualized unconscious mind, whereas for Lei Feng, it is Maoist revolutionary optimism. Additionally, both diaries have unusually strong inauthentic or ‘fake’ aspects. Although Hug-Hellmuth never admitted to writing the diary, most critics believed it came from her pen. Lei Feng's diary was revised through his own attempts to present himself as politically progressive, by editors, and through successive political movements that focused on the person behind the diary and made him one of the most widely-recognized figures in China. As such, the diaries are excellent windows into powerful and long-lasting ideological constructs.
Comparison of two ICCS conductors for MHD application

Two subscale, internally cooled, cabled superconductors (ICCSs) have been examined as candidates for use in a retrofit MHD (magnetohydrodynamic) topping cycle magnet. One of these was a 3*3*3 cable in which all the strands were multifilamentary NbTi stabilized with copper. The other was a 3*3*3 cable in which two strands in each of the nine triplets wa OFHC copper and one was multifilamentary NbTi. The overall copper-to-superconductor ratio for each of the two 27-strand cables was approximately the same. The two conductors were cowound onto a grooved mandrel in such a way that they could be tested alternately. Each sample was instrumented with a heater at the center of the conductor length and with a pressure transducer, four pairs of voltage taps, and one iron-doped gold/constantan thermocouple. Performance tests of the conductors were made at 6-, 7-, and 7.8-T background magnetic fields and at heater input energies ranging from 60 mJ/cm/sup 3/ to 1758 mJ/cm/sup 3/ of conductor. The results of these tests and their significance for MHD magnet design and economics are discussed. >
Epitaxial Ba0.5Sr0.5TiO3–GaN heterostructures with abrupt interfaces

Abstract Epitaxial heterostructures incorporating the complex ferroelectric oxide Ba 0.5 Sr 0.5 TiO 3 (BST) and GaN were prepared using a combination of RF magnetron sputtering and metalorganic chemical vapor deposition for the respective layers. The heterostructures were grown on c -plane sapphire substrates and were characterized using X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning transmission electron microscopy (STEM). This analysis showed that at substrate temperatures of 650 °C, BST films grow epitaxially on GaN with a {1 1 1} orientation and that the GaN–BST interface is smooth and abrupt, with disorder confined to grain boundaries and the interface plane. The film morphology is grainy indicating a 3-D growth mode. High-temperature post-deposition annealing studies suggest no interface reactions up to 900 °C. These results demonstrate that complex oxides like BST can be integrated with wide bandgap semiconductors like GaN and open exciting possibilities for new multifunctional devices.
Drought-caused delay in nesting of Sonoran Desert birds and its facilitation of parasite- and predator-mediated variation in reproductive success

ABSTRACT As our understanding of climate change has increased, so has our awareness of the impacts of these changes on biotic systems. Climate models are nearly unanimous in their predictions for increased drought frequency in southwestern North America, and delays in nest initiation due to drought may influence nesting success and productivity for many Sonoran Desert bird species. In southeastern California and western Arizona in 2004–2009, we found negative correlations for 13 of 13 species between nest initiation date and rainfall accumulation during the preceding 4-month winter rainy season. Nesting was delayed more than 3 weeks for some species during extreme droughts in 2006 and 2007. During 2004–2009, we found a significant negative effect of nest initiation date on nest survival probability (β = −0.031 ± 0.005 SE, P < 0.001) for the four species of greatest sample size. To investigate the role of nesting delay in nesting success and productivity, in 2010 we conducted a manipulative experiment wit...
The genetics of Tourette disorder

Tourette disorder (TD) is a childhood onset neuropsychiatric syndrome defined by persistent motor and vocal tics. Despite a long-standing consensus for a strong genetic contribution, the pace of discovery compared to other disorders of similar prevalence has been slow, due in part to a paucity of studies and both clinical heterogeneity and a complex genetic architecture. However, the potential for rapid progress is high. Recent rare variant findings have pointed to the importance of copy number variation, the overlap of risks among distinct diagnostic entities, the contribution of novel molecular mechanisms, and the value of family based studies. Finally, analysis of a cohort of sufficient size to identify common polymorphisms of plausible effect is underway, promising key information regarding the contribution of common alleles to TD.
Accounting for the Solar Acoustic and Luminosity Variations from the Deep Convection Zone

Recent helioseismic observations (Duvall et al.) have demonstrated how new data analysis techniques can determine local changes in the acoustic properties beneath the photosphere. The recent results provide compelling evidence of a latitudinal sound speed variation. Using results from numerical simulations, we show here how this acoustic variation has the correct form and amplitude needed to account for the previously observed solar photometric changes. In this picture, both the acoustic and irradiance changes may be caused by magnetically induced entropy fluctuations near the base of the solar convection zone.
The Evaluation of Cervical Intraepithelial Neoplasia with Microcolpohysteroscopy: A Preliminary Report

ABSTRACT Microcolpohysteroscopy allows the observation of the cervix and endocervical canal at various magnifications, 1:1 to 1:150. More importantly, it has permitted an examination of a squamocol...
Active and passive observers' attraction to a self-disclosing other☆

Abstract Active observer (participant) subjects were induced to make either a high or a low intimacy disclosure about themselves to a partner. Their (videotaped confederate) partner then disclosed either intimately or non-intimately in return. The impressions and attributions of these subjects were compared to the predictions of passive observer subjects (non-participants) who were each furnished with the original instructions, heard a tape recording of a different active observer's disclosure, and watched the same videotape of the confederate that person had seen. As expected, both active observers' responses and passive observers' predictions indicated a preference for the intimate partner. In addition, passive observers' attraction predictions were less positive than active observers' reports. But contrary to the hypotheses, passive observers predicted that active observers would attribute the partner's disclosure more to personalistic causes than was actually the case, and guessed inaccurately that active observers would interpret the partner's intimacy as an indicator of attraction. The methodological implications of these active-passive observer differences for research in self-disclosure and relationships are discussed.
FIELD EVALUATION OF STEEL GIRDER BRIDGE

The objective of the study was to verify the load-carrying capacity of an existing steel girder bridge. The selected structure was a 70-year-old deteriorated bridge in Michigan. The load-carrying capacity of the bridge was in question because of extensive corrosion of the steel girders. An initial rating indicated that the bridge had a marginal operating rating factor for 11-axle two-unit trucks, which are the heaviest vehicles allowed in Michigan. To avoid the load limit posting, it was decided that investigators would verify by nondestructive testing whether the bridge is safe to carry normal truck traffic. The test procedures used on the selected bridge included tests for obtaining stress histogram measurements and weigh-in-motion measurements and a proof load test. The methodology and the results are described.
Importance of 6 p.m. in Hamster Timekeeping Evidenced by Computer Analysis of Wheel-Running Activity

We addressed the question whether the clock signal for hamsters to become active occurs at sundown throughout summer or at some constant time after noon (p.m. time). Ten female golden hamsters housed in wheel cages in a windowless room were exposed to 24-h light/dark (LD) cycles simulating the equinoxes (LD 12: 12), when the sun sets at 6 p.m. and rises at 6 a.m., and summer (LD 14: 10, 16: 8, and 18: 6), when the sun sets after 6 p.m. and rises before 6 a.m. The onset of behavioral estrus, a mask-free phase marker of the same clock that controls wheel-running, was observed every 4 days, and wheel revolutions were recorded every 5 min for 52 days. Computer analysis of the 5-min values averaged for all 10 hamsters revealed a clear onset of running for each LD exposure. Time in the windowless room is referenced to mid-L (room “noon”) of the LD cycles. Although L-off ranged from 6 p.m. in LD 12: 12 (6 h after mid-L) to 9 p.m. in LD 18: 6, estrus began close to 4 p.m. and running close to 6 p.m. in every LD c...
Frequency of seborrheic keratosis biopsies in the United States: a benchmark of skin lesion care quality and cost effectiveness.

Background. Most seborrheic keratoses may be readily clinically differentiated from skin cancer, but occasional lesions resemble atypical melanocytic neoplasms. Objective. To evaluate the frequency, cost, and intensity of procedures performed that result in the removal and histopathologic evaluation of seborrheic keratoses. Methods. Episodes of surgical removal of lesions that were identified as seborrheic keratoses by histologic identification were determined using Medicare Current Beneficiary Survey data from 1998 to 1999. These episodes were defined by a histopathology procedure code that is associated with a diagnosis code for seborrheic keratosis. We then identified what procedure(s) generated the histopathology specimen. Biopsy and shave procedures were considered “low intensity,” whereas excision and repair procedures were considered “high intensity.” Results. Dermatologists managed 85% of all episodes of seborrheic keratoses. Dermatologists managed 89% of seborrheic keratosis episodes using low-intensity procedures compared with 51% by other specialties. For nondermatologists, 46% of the treatment cost ($9 million) to Medicare was generated from high-intensity management compared with 15% by dermatologists ($6 million). Conclusion. There is a significant difference in the management of suspicious pigmented lesions between dermatologists and other specialists. This affects both the cost and quality of care.
Effects of Various Sightsinging Strategies on Nonmusic Majors' Pitch Accuracy

The purposes of this study were to determine if different strategies used to practice sightsinging would aid nonmusic students in accurately performing such a task; if improvement in sightsinging w...
A framework for studying research collaboration

This paper describes a methodological and topical framework for studying collaboration in research settings. The framework is intended to capture the central activities and issues in research collaboration, and to represent them in a way that can inform the design of computer support. In this paper we present our starting premises for studying collaboration, describe our use of qualitative and naturalistic methods, and report our preliminary findings.
Dynamic solver selection for an Internet simulation backbone

This current research is to develop automated solver selection capabilities necessary to achieve a "simulation backbone" in which domain experts can plug in simulation solvers they have developed and have these automatically available for use to designers and researchers whose simulation requirements take them into that discipline. The ultimate goal is a one-button press execution of a simulation performed using the correct simulation solvers on machines distributed over the Internet using software automatically taken from the Internet.In order to achieve this objective, we have started to develop a framework to identify and characterize a system of computer-interpretable rules that describe when a theoretical and computational model is applicable to a design simulation. For example, if a design model comprises some geometric volume and fluid flow conditions are specified, a rule can indicate that the problem is in the discipline of fluid dynamics. Depending on the specific shape and size of the volume and the velocity and viscosity of the fluid, rules can be used to further distinguish the problem as being in the sub-discipline of, for example, laminar, turbulent, or compressible flow. The existence of side effects, such as changes in heat transfer properties or aero-elastic effects, can also be inferred using rules that consider the results from a fluid dynamics simulation. The research scope has been limited to selected disciplines in mechanical engineering.
Why Parfit did not go far enough

Parfit has argued for the revolutionary thesis that personal identity does not matter in ordinary survival, only the R-relation does. “Reconciliationists,” such as Lewis, have tried to stop this revolution, arguing that both personal identity and the R-relation matter. The disagreement has been between those who hold that only the R-relation matters and those who hold that, in addition, personal identity matters. But there is a third option. I argue that Parfit is right that personal identity does not matter but he is wrong that the R-relation matters, and the reconciliationists are wrong to think both matter since neither does.
Serial Followup of the Contralateral Renal Size In Children With Multicystic Dysplastic Kidney

ABSTRACTPurpose: Multicystic dysplastic kidneys have negligible renal function and the contralateral kidney (solitary kidney) frequently exhibits abnormalities that may affect growth. We previously showed that nomograms related to renal size constructed from digitalized ultrasonographic measurements of renal parenchymal area are a sensitive measure of renal growth and correlate with functional mass. We assess the age-dependent characteristics of compensatory renal growth in infants and children with multicystic dysplastic kidneys by construction of a growth curve for the contralateral kidney, assess these characteristics in comparison to normal renal growth of right and left kidneys, analyze the extent of compensatory renal growth and evaluate abnormal growth in solitary kidneys in infants and children.Materials and Methods: From 1988 to 2000 we reviewed 152 serial sonograms from 48 patients with a diagnosis of multicystic dysplastic kidneys. We also reviewed 209 renal sonograms in patients whose studies,...
Individual differences in figural aftereffect potency: Aftereffect trace vs immediate stimulus context as a determiner of perception

When, given the same stimulus pattern, the direction of a perceptual response can be determined by either the strength of an aftereffect trace or by an immediately present stimulus context, field-independent Ss responded in accordance with the aftereffect trace, while field-dependent Ss’ perceptions were influenced by the immediately present stimulus context. The data at hand continue to demonstrate significant differences in aftereffect potency between field-independent and field-dependent Ss.
An experimental investigation of the ignition properties of hydrogen and carbon monoxide mixtures for syngas turbine applications

Abstract Ignition studies of simulated syngas mixtures of hydrogen (H2), carbon monoxide (CO), oxygen (O2), nitrogen (N2), and carbon dioxide (CO2) were performed using a rapid compression facility. Experiments were conducted using pressure time-histories and high-speed imaging to measure ignition delay times (τign), over a broad range of conditions relevant to current and proposed gas-turbine technologies, and which included fuel compositions consistent with typical gasification facilities. Specifically, the τign data spanned pressures from P = 7.1 to 26.4 atm, temperatures from T = 855 to 1051 K, equivalence ratios from ϕ = 0.1 to 1.0, oxygen mole fractions from χ O 2 = 15 % to 20% and H2:CO ratios from H2:CO = 0.25 to 4.0 (mole basis). Regression analysis yielded the following best-fit to the composite data set: τ ign = 3.7 × 10 - 6 P - 0.5 ϕ - 0.4 χ O 2 - 5.4 exp ( 12 , 500 / R [ cal/mol/K ] T ) In this expression, τign is the ignition delay time [ms], P is pressure [atm], T is temperature [K], ϕ is the equivalence ratio (based on the H2 and CO to O2 molar ratio), and χ O 2 is the oxygen mole fraction. The uncertainty in the measured values for τign is estimated as less than 30%. The experimental data are in good agreement with model predictions based on a recently proposed detailed reaction mechanism for H2 and CO.
Semiparametric efficient inferences for lifetime regression model with time-dependent covariates

Through a threshold equation, we propose a time-transformed accelerated failure time (AFT) model with time-dependent covariate history in survival analysis. This model contains a general class of semiparametric lifetime regression models, including AFT with identical time-scale and a wide spectrum of Cox’s hazard regression models and their frailty variants. We first construct the semiparametric efficient statistical inferences on the AFT model with identical time-scale. The theoretical semiparametric Fisher information bound is explicitly derived under right-censored data setting. And the overidentified estimating equation (OEE) approach based on two martingale processes is shown to achieve this semiparametric efficiency bound. Extensions of the semiparametric efficient statistical inferences to the time-transformed AFT versions are also discussed. We also conclude that most log-rank estimating equations would suffer severe information loss primarily caused by wiggling pattern of the baseline hazard function, while the OEE approach can alleviate the damaging effects. A simulated biological life history example is numerically studied.
Equivalence of the free fermion model to the ground state of the linear XY model

Abstract We show that the 8-vertex free fermion model with electric fields is equivalent to the ground state of the linear XY model in the presence of a magnetic field, under appropriate relations between coupling parameters.
Butyric acid and hydrogen production by Clostridium tyrobutyricum ATCC 25755 and mutants

Abstract Clostridium tyrobutyricum produces butyric acid, acetic acid, hydrogen and carbon dioxide as its main fermentation products. In this work, mutants with inactivated pta gene, encoding phosphotransacetylase (PTA) and ack gene, encoding acetate kinase (AK), were studied for their potential to improve butyric acid production in the fermentation. PTA and AK are two key enzymes in the acetate-producing pathway. PTA and AK activities in the pta -deleted mutant (PPTA-Em) were reduced by 44% and 91%, respectively, whereas AK activity in the ack -deleted mutant (PAK-Em) decreased by 50%. Meanwhile, the activity of butyrate kinase (BK) in PPTA-Em increased by 44% and hydrogenase activity in PAK-Em increased by 40%. As compared with the wild type, the specific growth rate of the mutants decreased by 32% (from 0.28 to 0.19 h −1 ) because of the impaired PTA-AK pathway. Meanwhile, butyric acid production by these mutants was improved greatly, with higher butyric acid yield (>0.4 g/g versus 0.34 g/g) and final concentration (43 g/L versus 29 g/L), which also indicated that the mutants had better tolerance to butyric acid inhibition. However, acetate production in the mutants was not significantly reduced even though more butyrate was produced from glucose, suggesting the existence of additional acetate forming pathway in C. tyrobutyricum . Also, hydrogen production by PAK-Em mutant increased significantly, with higher hydrogen yield (2.61 mol/mol glucose versus 1.35 mol/mol glucose) and H 2 /CO 2 ratio (1.43 versus 1.08). The SDS-PAGE also showed significantly different expression levels of proteins with molecular mass around 32 and 70 kDa. These results suggested that integrational mutagenesis resulted in global metabolic shift and phenotypic changes, which also improved production of butyric acid and hydrogen from glucose in the fermentation.
Harnessing Light to Create Defect-Free, Hierarchically Structured Polymeric Materials

Computer simulations reveal how photoinduced chemical reactions in polymeric mixtures can be exploited to create long-range order in materials with features that range from the submicron to the nanoscale. The process is initiated by shining a spatially uniform light on a photosensitive AB binary blend, which thereby undergoes both a reversible chemical reaction and a phase separation. When a well-collimated, higher intensity light is rastered over the sample, the system forms defect-free, spatially periodic structures. If a nonreactive homopolymer C is added to the system, this component localizes in regions that are irradiated with a higher intensity light, and one can effectively “write” a pattern of C onto the AB film. Rastering over the ternary blend with the collimated light now leads to hierarchically ordered patterns of A, B, and C. Because our approach involves homopolymers, it significantly expands the range of materials that can be fashioned into a periodic pattern. The findings point to a facil...
Age-related differences in mouse Schwann cell response to cyclic AMP

Abstract An elevation of intracellular cyclic adenosine 3′, 5′-monophosphate (cAMP) is known to stimulate proliferation and expression of surface galactocerebroside (galC) in cultured Schwann cells from newborn rats and mice. We investigated the age-related differences in proliferative and differentiating responses of Schwann cells to forskolin, an adenylate cyclase activator, in mice at postnatal days (P) 3, 10 and 30. The proportion of surface galC-positive cells decreased progressively with time in all ages during the initial three days in vitro (DIV) but the proportion of Schwann cells expressing surface gaLC at P30 was lower than that at P3 or P10. Administration of 50 μM forskolin in the media on the four DIV induced surface gaLC expression in Schwann cells from P3 and P10 mice but not from P30 mice. Forskolin also stimulated the proliferation of Schwann cells from P3 and P10 mice in media containing 2% fetal bovine serum (FBS) but not those from P30 mice, which, however, proliferated in media containing 10% FBS. These results suggest that Schwann cells in suckling mice are more sensitive to cAMP in both proliferative and differentiating responses than in adult. These different responses in vitro may reflect differences in the intrinsic metabolic status of Schwann cells in vivo since myelin-forming Schwann cells proliferate actively prior to myelination but cease or become less active in proliferation once myelination progresses.
Fast optimal alignment

We show how to speed up sequence alignment algorithms of the type introduced by Needleman and Wunsch (and generalized by Sellers and others). Faster alignment algorithms have been introduced, but always at the cost of possibly getting sub-optimal alignments. Our modification results in the optimal alignment still being found, often in 1/10 the usual time. What we do is reorder the computation of the usual alignment matrix so that the optimal alignment is ordinarily found when only a small fraction of the matrix is filled. The number of matrix elements which have to be computed is related to the distance between the sequences being aligned; the better the optimal alignment, the faster the algorithm runs.
ON THE FOKKER-PLANCK EQUATION IN THE STOCHASTIC THEORY OF MORTALITY.II.

This is the continuation of part I, which was published in the September, 1963, issue ofThe Bulletin. Section 5 treats the special case in which the left absorbing barrier recedes to −∞, leaving essentially only one barrier at a finite distance Λ (>0) from the origin. The eigenfunctions are now parabolic cylinder functions. The limiting cases Λ→+∞ and Λ→0 are also considered. Though meaningless for practical applications to our problem, they are of interest, mathematically, because the Green’s function for the solution of the Fokker-Planck equation assumes a particularly simple form. In section 6 we study, by means of an example, how the “force of mortality” may vary with time before attaining its final asymptotic value. Section7, still dealing with only one absorbing barrier, shows that our results for “strong homeostasis” are identical with those derived by Chandrasekhar for the escape of particles through a potential barrier in the limiting case of quasi-static flow. Precise conditions are given for the validity of both the quasi-static and the Smoluchowski approximations to the Fokker-Planck equation. Finally, in section 8, a brief mention is made of Gevrey’s method for the solution of parabolic partial differential equations.
Conformational study by intrinsic viscosities of the starch-iodine complex

The amylose molecule is extended by the insertion of iodine in quantities up to a ratio of one molecule per turn of the helix. Ordinary cornstarch and its amylopectin fraction do not respond in the same manner. As the iodine content was increased the intrinsic viscosity [η] rose from 0.55 to 1.45 dl/g, then remained constant. In this same range theHuggins' interaction parameterk′ for the dependence of reduced viscosity [η sp/C] on iodine concentration rose from 0.31 to 5.65 and continued to increase. Reduction ofd[η]/dT by complexing from −0.36 × 10−2 to −0.23 × 10−2 dl/g/deg provided an independent measure of the flexibility of the molecule and revealed that iodine stiffens the helix in some manner. The dipolar interaction between iodine and the helix restricts conformational changes and increases the average extension. As more iodine molecules enter the helical chain the average distribution of molecular segments relative to the center of mass of the molecule spreads outward.
Multiscale branch-and-bound image database search

ABSTRACT This paper presents a formal framework for designing search algorithms which can identify target images by thespatial distribution of color, edge and texture attributes. The framework is based on a multiscale representation of both the image data, and the associated parameter space that must be searched. We define a general form for the distance function which insures that branch and bound search can be used to find the globally optimal match. Ourdistance function depends on the choice of a convex measure of feature distance. For this purpose, we propose theL1 norm and some other alternative choices such as the Kuilback-Liebler and divergence distances. Experimental results indicate that the multiscale approach can improve search performance with minimal computational cost.Keyword: multiscale search, image similarity, content-based retrieval, color histogram, convex function 1 INTRODUCTION One method for searching large databases of natural images is to retrieve images with color, texture and edge
Power in mixed exchange networks: a rational choice model

Abstract Using the logic of rational choice and extending the models of exchange introduced by Taylor and Coleman (1979) [Taylor, D.G., Coleman, J.S., 1979. Equilibrating process in social networks: a model for conceptualization and analysis. In: Holland, P.W., Leinhardt, S. (Eds.), Perspectives on Social Network Research. Academic Press, New York, pp. 257–300.] and Yamaguchi (1996) [Yamaguchi, K., 1996. Power in the network of substitutable/complementary exchange relations: a rational-choice model and an analysis of power centralization. American Sociological Review 61, 308–332.], this paper clarifies some major principles regarding the distribution of power in mixed exchange networks. Mixed exchange networks are exchange networks where both substitutability and complementarity exist among multiple exchange relations of an actor. Illustrative examples of 15 distinct dating networks consisting of two boys and two girls are used for the purpose of clarifying and applying those principles. General implications for both network studies and rational choice theories of the theory developed in this paper are also discussed.
Relative quantitation of protein nitration by liquid chromatography–mass spectrometry using isotope-coded dimethyl labeling and chemoprecipitation

Protein nitration has been recognized as an important biomarker for nitroxidative stress associated with various diseases. While identification of protein targets for nitration is important, its quantitative profiling also is necessary to understand the biological impact of this low-abundance posttranslational modification. We have previously reported an efficient and straightforward enrichment method for nitropeptides to reduce sample complexity and permit unambiguous site-specific identifications by LC–MS analyses. This approach relies on two chemical derivatization steps: specifically reductive methylation of aliphatic amines and, then, conversion of nitrotyrosines to the corresponding aminotyrosines before their selective capture by a solid-phase reagent we introduced previously. Hence, the method inherently offers the opportunity for relative quantitation of nitropeptides by using isotopic variants of formaldehyde for reductive methylation. This simple method was tested via LC–MS analyses of differently N-methylated nitropeptides and nitroubiquitin as a model nitroprotein enriched from human serum albumin digest and from human plasma, respectively.
H-infinity synthesis using a bilinear pole shifting transform

An H-inifinity control law design is presented for a benchmark problem consisting of an undamped pair of spring-coupled masses with a sensor and actuator that are not collocated. This simple mechanical system captures many of the salient features of more complex aircraft and space structure vibration control problems. The H-infinity problem formulation enables the issue of stability robustness in the face of large mass and spring constant variation to be directly addressed. Constraints on closed-loop dominant pole locations and settling time are accommodated via a simple s-plane bilinear transform. The transform parameter can give direct control of closed-loop disturbance settling time and controller open-loop pole-zero locations. A four-state H-infinity minimum phase controller was found to meet the given specifications of each design. Detailed analysis on the tradeoffs of sensor noise vs control energy are also presented.
Specimen thickness determination in transmission electron microscopy in the general case

Abstract A technique is described to determine the foil thickness of transparent specimens as used in transmission electron microscopy. The foil thickness is determined from the changes of the projected widths of pairs of latex balls on both surfaces of the specimens during tilling (large angles). The accuracy of the method is investigated critically. In routine work, a standard deviation of less than 4% is obtainable.
Effects of psychoeducational care for adult surgical patients: a meta-analysis of 191 studies

A quantitative review of the literature (meta-analysis) was conducted with 191 studies of the effects of psychoeducational care on the recovery, postsurgical pain and psychological distress of adult surgical patients. Studies issued between 1963 and 1989 were included in the review. Statistically reliable, small to moderate sized beneficial effects were found on recovery, postoperative pain and psychological distress. In further analyses it was shown that these beneficial effects were not an artifact of the biases associated with the decision whether to publish a paper, low internal validity, measurement subjectivity, or a Hawthorne effect. The overall efficacy of psychoeducational care provided to adult surgical patients has been reconfirmed with this larger sample of studies. It is particularly noteworthy that these findings are of more than strictly historical interest. Despite changes in health care delivery, beneficial effects continue even in studies issued between 1985 and 1989. Implications for clinical practice are drawn.
Appendiceal wall thickening at CT in asymptomatic patients with extraintestinal malignancy may mimic appendicitis

The purpose of this study was to describe the CT appearance and determine the prevalence of thick-walled appendices in patients with an extraintestinal primary malignancy. This potential mimic of appendicitis may occur in up to 2% of cancer patients. Awareness of this pitfall is important to avoid unnecessary laparotomy in this patient population.
Multiple cues from multiple habitats: Effect on metamorphosis of the Florida stone crab, Menippe mercenaria

Abstract The Florida stone crab, Menippe mercenaria, is an economically and ecologically important species that ranges from North Carolina throughout the Caribbean and the southeastern Gulf of Mexico. However, there is little known about its early life history stages as compared to other commercially important species in the region. The goal of this research was to examine effects of putative cues on metamorphosis from the megalopa stage to the first juvenile stage. Our study investigated the effect of water-soluble exudates from four substrata, as well as natural biofilms, and exudates from adult stone crabs. In addition, the influence of natural substrata was compared to that of artificial substrata. Adult exudate had no significant effect on metamorphosis, despite a wide range of tested concentrations. In contrast, there was a significant effect on mean time to metamorphosis in experimental groups exposed to multiple cues associated with the brown alga Sargassum fluitans, rubble from stone crab habitat, the eastern oyster Crassostrea virginica, and biofilms associated with the oyster. Furthermore, we provide evidence for metamorphic responses to water-soluble chemical cues, as well as biochemical and physical cues associated with different substrata. Overall results were coherent with the relevant body of previous work on metamorphosis of brachyuran crab larvae and indicate that both physical and chemical cues are important factors in facilitating the settlement and metamorphosis of M. mercenaria larvae in juvenile nursery habitat.
SPIREX — Near Infrared Astronomy from the South Pole

Over the next several years we will deploy a series of spectrometers, imagers, and telescopes at the South Pole as part of a project named SPIREX — for South Pole Infrared Explorer. Our goal is to survey a substantial area of the sky to study the origins of galaxies and stars.
Electrical excitability of early neurons in the human cerebral cortex during the second trimester of gestation.

Information about development of the human cerebral cortex (proliferation, migration, and differentiation of neurons) is largely based on postmortem histology. Physiological properties of developing human cortical neurons are difficult to access experimentally and therefore remain largely unexplored. Animal studies have shown that information about the arousal of electrical activity in individual cells within fundamental cortical zones (subventricular zone [SVZ], intermediate zone, subplate [SP], and cortical plate [CP]) is necessary for understanding normal brain development. Here we ask where, in what cortical zone, and when, in what gestational week (gw), human neurons acquire the ability to generate nerve impulses (action potentials [APs]). We performed electrical recordings from individual cells in acute brain slices harvested postmortem from the human fetal cerebral cortex (16--22 gw). Tetrodotoxin-sensitive Na 1 current occurs more frequently among CP cells and with significantly greater peak amplitudes than in SVZ. As early as 16 gw, a relatively small population of CP neurons (27%) was able to generate sodium APs upon direct current injection. Neurons located in the SP exhibited the highest level of cellular differentiation, as judged by their ability to fire repetitive APs. At 19 gw, a fraction of human CP and SP neurons possess bIV spectrin--positive axon initial segments populated with voltage-gated sodium channels (PanNav). These results yield the first physiological characterization of developing human fetal cortical neurons with preserved morphologies in intact surrounding brain tissue.
Cytoarchitecture of primitive brains: Golgi studies in flatworms

Notoplana acticola, a free-living polyclad flatworm, has a small but well-defined brain that controls behavior of peripherally based motoneurones. This is the most primitive brain currently being studied electrophysiologicaly, but little is known of its cytoarchitecture. Using a modified rapid Golgi method, we have investigated neurone configurations within this brain. Superficially the brain resembles those of other invertebrates, but its cells also possess many vertebrate features. There is a surprising diversity of cell types with complicated branching patterns. Multipolar neurones appear to be the most common type. A few typical invertebrate monopolar cells were also stained. Bipolar cells occur in the rind. Processes resembling dendritic spines were observed. Measurements of these indicate that they fall within the range found in other vertebrates and invertebrates. Small multipolar cells that could either be glial or interneurones were found scattered through the brain.