cssi/SciSciGPT-SciSciNet huggingface dataset:
Red Beds of Middle Pleistocene Olorgesailie Formation, Kenya: ABSTRACT

Middle Pleistocene lake sediments of the Olorgesailie Formation from the East African Rift Valley of Kenya contain red beds, with colors ranging from moderate orange pink to dark reddish brown (Munsell color chart). Two distinct mechanisms of hematite formation, distinguished by thin section and scanning electron microscope study, have produced the red sediments. In the first mechanism, hematite was formed in situ by dehydration of limonitic minerals. The limonitic minerals formed in soils of the source area and were transported to the depositional site mainly by adhering to clay particles. The elevated pH of the depositional environment accelerated the rate of hematite formation, producing ultrafine red coating on the clays. Red sediment formed by this mechanism occurs both as an undisturbed bed and as a reworked intraclast conglomerate. In the second mechanism, hematite is precipitated from ground water, possibly at elevated temperatures produced by the interaction of basaltic magma with water-saturated sediment. The hematite occurs in three forms: as cement within diatomaceous clay, as replaced or stained plant material, and within siliceous sinters. The sinters are red, have a pumice-like texture, and include diatoms that show effects of dissolution. These characteristics indicate formation of the sinters by boiling of near-surface water-saturated sediment. Red beds formed by this mechanism are redeposited and each of the three hematite forms dominates in specific localities. End_of_Article - Last_Page 934------------
Genotype specificity of the somatic embryogenesis response in cotton

Thirty eight cultivars, strains, and races ofGossypium were screened for somatic embryogenesis with the protocols developed as a model forG. hirsutum L. cv. Coker 312. Four classes of response were identified; high, moderate, low, and non-embryogenic. Four cultivars were further screened with 13 growth regulator regimes to determine if culture environment could change the classification or induce a higher level of response. The classification or level of response did not change. Screening of individual seedlings within a cultivar indicated that genotypic variation for embryogenesis existed. Highly embryogenic individuals were selected from cvs. Coker 312 and Paymaster 303 for use as germplasm sources for transfer of the embryogenic trait to other cultivars and genetic stocks. Only genetically responsive genotypes are amenable to the model developed for Coker 312.
Deep-Sea Microorganisms: In situ Response to Nutrient Enrichment

After inoculation of sterile organic materials on the deep-sea floor and in situ incubation for 1 year, relatively minute rates of microbial transformation were recorded. This extremely slow conversion rate, as well as the type and quantity of organic matter normally reaching the ocean floor, appear to characterize microbial life in the deep sea.
The attenuation and phase velocity of ultrasonic third sound for optically smooth and roughened substrates

The attenuation and phase velocity of third sound have been measured for propagation on optically smooth and roughened substrates and for ultrasonic frequencies in the 20–200 kHz range. The attenuation for both kinds of substrates is found to be proportional to the frequency and have a magnitude that increases with the amount of roughening. The data are found to be inconsistent with a number of proposed attenuation mechanisms. The phase velocity is nearly independent of the frequency. Pulse wave shapes change substantially as the third sound propagates along a substrate surface.
Pressure and temperature dependence of unimolecular bond fission reactions: An approach for combustion modelers

Abstract There exists a well recognized need for a critical overview of the rate data that go into combustion modeling. Modelers should be able to consult tables of parameters for combustion-relevant reactions that would enable the calculation of relevant rate constants as a function of temperature and pressure over the entire range of interest. A complete tabulation would include both uni- and bimolecular reactions; in this paper we focus on the analysis of unimolecular reactions. The approach is illustrated with unimolecular “falloff” calculations for formaldehyde, methane, ethane, butane, hexane, octane, and the ethyl radical.
Electron paramagnetic resonance and in situ photosensitivity investigation of the photorefractive polymer BisA-NAS:DEH

We have observed the electron paramagnetic resonance (EPR) signal in the photorefractive polymer BisA-NAS:DEH. The polymer is a mixture of the electro-optic polymer bisphernol A 4,4-nitroaminostilbene (BisA-NAS) with 29% by weight benzaldehyde diphenyl-hydrazone (DEH), a hole transport agent. The EPR signal was observed at 3431.590 G. Illumination of the photorefractive polymer by an Ar+ laser leads to an interesting phenomenon. With an aim to understand the photosensitivity of the photorefractive polymer, we have monitored the changes in the intensity of the EPR line. The measurements were done in situ at room temperature and liquid nitrogen temperature 77 K. The sample was loaded in an optical transmission cavity to facilitate the use of the laser. When the sample is illuminating with low laser intensity, illumination decreases the EPR signal while for higher laser intensity, the EPR signal grows. We provide a tentative explanation for this phenomenon. Low laser intensity introduces photoconductivity, which reduces the EPR signal, but does not create free radicals. For higher laser intensity, paramagnetic free radicals are formed contributing to the increase of the EPR signal. The relation between observed phenomenon and photosensitivity will be discussed. Also the EPR results at low temperature will be presented.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Optimal battery charging, Part I: Minimizing time-to-charge, energy loss, and temperature rise for OCV-resistance battery model

Abstract In this paper we present a closed-form solution to the problem of optimally charging a Li-ion battery. A combination of three cost functions is considered as the objective function: time-to-charge (TTC), energy losses (EL), and a temperature rise index (TRI). First, we consider the cost function of the optimization problem as a weighted sum of TTC and EL. We show that the optimal charging strategy in this case is the well-known Constant Current–Constant Voltage (CC–CV) policy with the value of the current in the CC stage being a function of the ratio of weighting on TTC and EL and of the resistance of the battery. Then, we extend the cost function to a weighted sum of TTC, EL and TRI and derive an analytical solution for the problem. It is shown that the analytical solution can be approximated by a CC–CV with the value of current in the CC stage being a function of ratio of weighting on TTC and EL, resistance of the battery and the effective thermal resistance.
Corpi, Murakami, and Contemporary Hardboiled Fiction

In her paper, "Corpi, Murakami, and Contemporary Hardboiled Fiction," Cathy Steblyk discusses comparatively texts by contemporary detective fiction writers, one an ethnic-minority USAmerican and the other Japanese. Steblyk proposes that in detective fiction since the late 1980s, morally or ethically contestable sites of history have been given a postmortem by contemporary authors who are interested in restoring the lost parts of cultural histories. Detective fictions by feminist US-Chicana author Lucha Corpi and Japanese writer Murakami Haruki show how recent fiction from around the globe uses the hardboiled genre for the purposes of exploring past injustices and offering revisionist histories. The authors isolate crimes of mis-representation, interpret "historical fact" both analytically and empathetically, and act as a social vehicle of change. Steblyk finds that these recent detective fictions suggest, in an unexpectedly modernist way, a review of historical cultural narratives in order to redress history. By using the elements of the hardboiled in part against itself -similar to other recent neo-modernist authors of hardboiled fiction -Corpi's and Murakami's texts offer a metacritical commentary on detection in order to show how knowledge (crime) is produced. By placing themselves self-consciously in text, these contemporary fictions open up narratives and retrieve other bodies lost to certain legitimated, patriarchal, imperialist, cultural, or social histories. Cathy Steblyk, "Corpi, Murakami, and Contemporary Hardboiled Fiction" page 2 of 12 CLCWeb: Comparative Literature and Culture 5.2 (2003):
The Coordination of Hydraulic Turbine Governors for Power System Operation

The methods of adjustment and operation of the governors of hydraulic turbine generating units, in attempting to meet conflicting requirements, have occasionally developed over the past decade in directions different than would be suggested by the rapidly developing science of control. The most prominent factors contributing to the divergence have been the obscuring of proper speed control for individual units by interconnection into large systems, and the compromise of speed control characteristics for the superposition of t e-line controls. In the hydrodominated systems of the Northwest, frequency control has been understandably less efficient than in steam dominated systems.
Negative feedback that improves information transmission in yeast signalling

Haploid Saccharomyces cerevisiae yeast cells use a prototypic cell signalling system to transmit information about the extracellular concentration of mating pheromone secreted by potential mating partners. The ability of cells to respond distinguishably to different pheromone concentrations depends on how much information about pheromone concentration the system can transmit. Here we show that the mitogen-activated protein kinase Fus3 mediates fast-acting negative feedback that adjusts the dose response of the downstream system response to match the dose response of receptor-ligand binding. This 'dose-response alignment', defined by a linear relationship between receptor occupancy and downstream response, can improve the fidelity of information transmission by making downstream responses corresponding to different receptor occupancies more distinguishable and reducing amplification of stochastic noise during signal transmission. We also show that one target of the feedback is a previously uncharacterized signal-promoting function of the regulator of G-protein signalling protein Sst2. Our work suggests that negative feedback is a general mechanism used in signalling systems to align dose responses and thereby increase the fidelity of information transmission.
Modeling CPU energy consumption for energy efficient scheduling

In the past few years, we have seen the rising popularity of multi-core systems, including the 4, 6, and 8-cores present in i7 processors from Intel, and the 8 and 12 cores present in Magny-Cours processors from AMD. There is a general trend that newer processors have more and more number of cores. A study [6] showed that, in data centers, the CPU load is around 10-50%; thus, when multi-core processors are used in data centers, many of the cores will be unused for a majority of the time. Such a scenario is also true for a casual desktop PC user. As an idle core still consumes energy, from the perspective of saving energy, it is important to ensure that the idle cores are put in the lowest energy state and unnecessary wakeups for these idle cores are avoided. This will ensure the lowest energy consumption for a given set of tasks.The precursor step towards developing an energy efficient CPU scheduler requires an understanding of the relation between the type of tasks and their corresponding power profile. In this paper, we show that the power profile of a task is dependent on the type of processor cycles executed by the task. We further develop a model that can predict the power consumption based on the processor cycles executed by the task. We conclude our paper showing initial results on how such a model can be used to schedule tasks and save energy.
The mechanism of in vitro formation of irreversibly sickled cells and modes of action of its inhibitors

When red blood cells from sickle-cell patients were exposed to repeated cycles of deoxygenation and reoxygenation (one cycle was 5 min), dehydration of the cells was observed after several cycles of the sickling-desickling process. These dehydrated cells still maintained a biconcave form after 1 h of such cycling, but they started to take the form of irreversibly sickled cells after several hours. If red cells were simply kept deoxygenated for 16 h, neither dehydrated cells nor irreversibly sickled cells were formed. The formation of dehydrated cells was inhibited either by elimination of Ca2+ from the medium, or by the increase of K+ concentration in the medium. Under conditions in which dehydrated cells were not formed, i.e., deoxygenation incubation (either in the absence or presence of Ca2+) or the deoxygenation-reoxygenation cycling in the absence of Ca2+, 15-25% of cellular K+ leaked out during 4 h of incubation. When dehydrated cells were formed in deoxygenation-reoxygenation cycling in the presence of Ca2+, 40-50% of K+ was lost in 4 h. Two different types of inhibitor were found. The first type includes inhibitors of the Ca2+-activated K+ efflux, such as quinine, quinidine or tetraethylammonium chloride. These compounds suppressed both the K+ efflux and the formation of dehydrated cells. The second type includes calmodulin-interacting drugs. For example, chlorpromazine (20 microM) inhibited the formation of dehydrated cells almost completely, even though it did not inhibit the K+ efflux remarkably. Several other calmodulin-binding drugs were found to inhibit the formation of dehydrated cells similarly, and the potency of these drugs to inhibit the formation seems to be related to the binding affinity of these drugs to calmodulin.
Thioctic Acid in Complete and Deficient Diets for Chicks

ABSTRACT THIOCTIC acid (6,8-dithiooctanoic acid, lipoic acid, protogen) is known to be an important growth factor for protozoa and bacteria, as well as a component of certain enzyme systems in microorganisms and animal tissues (see reviews by Gunsalus, 1954; and Reed and DeBusk, 1954). Despite little evidence for its growth promoting activity in higher animals, thioctic acid has been called a vitamin (Seaman, 1952; Anonymous, 1953; Fischer, 1955) and has been included as a B vitamin in recent reviews on the vitamin B complex (Cheldelin, 1954; Johnson, 1955; Plaut and Betheil, 1956). DeBusk and Williams (1955) reported that thioctic acid added to a purified diet stimulated the growth of White Leghorn chicks and of Wistar rats. However, Stokstad, Broquist and Patterson (1953) had reported earlier that they could not produce a growth response with thioctic acid in chicks or rats fed a purified diet. Recently, Stokstad et al. (1956) and workers . . .
A comment on ø44 Euclidean field theory

Abstract We remark that an “old fashioned” approach to o 4 4 based on perturbation theory leads naturally to the necessity of considering also “antiferromagnetic actions” for the study of the ultraviolet limit. This type of cut-off theories seems to have never been considered.
Simultaneous Electrochemical Detection of Nitric Oxide and Carbon Monoxide Generated from Mouse Kidney Organ Tissues

A planar-type amperometric dual microsensor for simultaneous detection of nitric oxide and carbon monoxide is presented. The sensor consists of a dual platinum microdisk-based working electrode (WE) and a Ag/AgCl counter/reference electrode covered with an expanded poly(tetrafluoroethylene) (Tetra-tex) gas-permeable membrane. The dual WE possesses two different platinized platinum disks (WE1 and WE2, 250 and 25 μm in diameter, respectively). The larger WE1 is further modified with electrochemical deposition of tin. Use of two sensing disks different in their size as well as in their surface modification produces apparently different sensitivity ratios of NO to CO at WE1 and at WE2 (∼2 and ∼10, respectively) that are induced by favorable CO oxidation on the surface of tin versus platinum. Anodic currents independently measured at WE1 and at WE2 are successfully converted to the concentrations of NO and CO in the co-presence of these gases using the differentiated sensitivities at each electrode. The sensor...
Age of onset in bipolar and unipolar illness with and without delusions or hallucinations.

Abstract This study examined the differential association of unipolar and bipolar major affective disorder and the presence or absence of delusions or hallucinations with a number of age of onset indices. Earlier age of onset tended to be found in bipolar patients and patients with psychotic features. When the joint effect of polarity and psychotic features were examined, polarity was more highly related to various age of onset indices than psychotic features. However, these features were uniquely associated with a subset of indices beyond that accounted for by bipolarity. The implications of these findings are discussed.
Multifunctional Nanowire Bioscaffolds on Titanium

This paper reports a new fabrication of multifunctional nanowire bioscaffolds directly on titanium (Ti) through a simple and scale-up easy hydrothermal reaction of alkali with the Ti metal without using any seeds, templates, TiO2 powder, or stabilizers. The nanowires root firmly inside the Ti substrate and grow on top to eventually self-assemble into macroporous scaffolds. The effects of the alkali concentration, reaction time, and temperature on the bioscaffold morphologies were investigated. The novel solid-state chemistry for the nanowires' downward/upward co-growth and the accompanied self-assembly were tackled. Thus-formed coating of scaffolds on the metal implant surface, mimicking the natural extracellular matrix in structure, can promote cell adhesion and proliferation on Ti implant and perform controlled on-site drug release and photocatalytic sterilization.
O40: Perceived Lower Availability of Neighborhood Food Stores of Low-Income Older Adults in Northeast Georgia

food marketing to children. Sources included: company websites, reports and press releases, media clippings, Children’s Food and Beverage Advertising Initiative pledges, and communications with companies. Outcome Measures and Analysis: Researchers assessed company nutrition standards for marketing to children, including calories/portion size, total fat, saturated fat, trans fat, sugars, sodium, and positive nutrient content (fruits, vegetables, whole grains, vitamins and minerals). Researchers compared companies’ nutrition standards to each other, to companies’ product portfolios, and to recommended guidelines for responsible food marketing to children. Results: Thirteen of the 22 food companies (59%) had nutrition standards for food marketing to children. Of the 13 companies with nutrition standards, all set limits on calories, saturated fat, trans fat, sugars, and sodium. Five companies (38%) had requirements for positive nutrient content. None of the companies had standards as strong as recommended guidelines for food marketing to children. Conclusions and Implications: Nutrition standards for marketing to children vary greatly across companies. Standards vary to maximize companies’ ability to market their existing products. Although about half of companies have nutrition standards that are consistent with recommended guidelines for food marketing to children, as a complete package, companies’ nutrition standards are weaker than recommended. These findings suggest the need for a uniform set of nutrition standards and they help to inform the current state of self-regulation of food marketing to children.
Hematopoietic cells from CD155-transgenic mice express CD155 and support poliovirus replication ex vivo

Despite identification of the poliovirus (PV) receptor (CD155), mechanisms by which this molecule mediates paralytic disease remain obscure. Unanswered questions include CD155 localization in human tissues, the nature of cells supporting the first round of replication, identity of nonneural replication sites, and route of entry into the CNS. In earlier work, we showed that CD155 is expressed on primary human monocytes and that these cells support low, but statistically significant, levels of PV replication ex vivo without prior culturing. We hypothesize that monocytes support PV replication in vivo and that they contribute to pathogenesis. In the current study, we tested whether CD155-transgenic mouse hematopoietic cells express cell surface CD155 and whether these cells support PV replication. We found that the majority of monocyte/macrophages from peritoneal washes express CD155. In addition, 26-32% of CD155-transgenic bone marrow and spleen cells express CD155 on monocyte/macrophages, T cells and hematopoietic precursor cells. Various tissues supported PV replication without pre-culturing, however, pre-culturing or pre-treatment of mice with thioglycollate increased virus yield. These results are consistent with those from human cells and suggest that the CD155 transgenic mouse model is useful to help understand the role of hematopoietic cells in PV pathogenesis.
Some observations on performance-based and reliability-based seismic design of asymmetric building structures

In previous work by the second author and others, a framework for a reliability-based, performance-based seismic design procedure was presented. That framework was based on static pushover analyses of two-dimensional models of building structures. In this paper, some preliminary observations and results are presented from a study in which the framework is extended to be used with three-dimensional analysis models to explicitly account for the torsional behavior of asymmetric building structures.
Dynamic Interactions of High Speed Tracked Air Cushion Vehicles With Their Guideways: Part I of a Parametric Study

THE VEHICLE-GUIDEWAY SYSTEM IS MODELED AS AN ARBITRARY NUMBER OF LUMPED, DOUBLY-SPRUNG VEHICLE MASS SYSTEMS TRAVELING IN TANDEM ALONG SIMPLE SUPPORTED BEAMS. THE VEHICLE LOAD IS TRANSMITTED TO THE GUIDEWAY AS A TIME-VARYING UNIFORM PRESSURE COMPATIBLE WITH VEHICLE MOTION. EFFECTS OF THE DIMENSIONLESS SYSTEM PARAMETERS ON VEHICLE HEAVE ACCELERATION, AND GUIDEWAY DEFLECTIONS AND BENDING MOMENTS AT HIGH VEHICLE SPEEDS ARE EVALUATED. BY PROPER CHOICE OF PARAMETERS, PASSENGER COMPARTMENT HEAVE ACCELERATIONS CAN BE MINIMIZED, ALTHOUGH TO KEEP THIS ACCELERATION BELOW 0.05G FOR VEHICLES TRAVELING 100-300 MPH REQUIRES SYSTEMS WITH LOW VEHICLE TO BEAM MASS AND FREQUENCY RATIOS AS WELL AS LOW VEHICLE LOWER TO UPPER MASS RATIOS. THE BENEFITS OF DISTRIBUTED AIR CUSHION PRESSURE TO VEHICLE AND GUIDEWAY DESIGN ARE SHOWN. /AUTHOR/
A rat model for choroidal neovascularization using subretinal lipid hydroperoxide injection.

The purpose of this study was to develop and characterize a rat model of choroidal neovascularization (CNV) as occurs in age-related macular degeneration. The lipid hydroperoxide 13(S)-hydroperoxy-9Z,11E-octadecadienoic acid (HpODE) is found in submacular Bruch’s membrane in aged humans and has been reported to generate neovascularization in a rabbit model. Three weeks after a single subretinal injection of 30 μg of HpODE, eyes of Sprague-Dawley rats were harvested. Follow-up fluorescein angiography was done on other animals until 5 weeks postinjection. Histological studies, immunohistochemical staining, and flatmount choroids for CNV measurements were performed. In addition, we used murine neuronal, bovine endothelial, and human ARPE19 cells for testing the in vitro effects of HpODE. CNV developed in 85.7% of HpODE-injected eyes. The neovascular areas were significantly greater in HpODE-injected eyes compared with those in control eyes (P = 0.023). The CNV had maximum dye leakage at 3 weeks, which subsided by the 5th week. Histologically, CNV extended from the choriocapillaris into the subretinal space. ED1-positive macrophages were recruited to the site. In vitro assays demonstrated that only 30 ng/ml HpODE induced cell proliferation and migration of endothelial cells. HpODE-induced CNV was highly reproducible, and its natural course seems to be ideal for evaluating therapeutic modalities. Because HpODE has been isolated from aged humans, the HpODE-induced rat model seems to be a relevant experimental model for CNV in age-related macular degeneration.
External Validation of the National Healthcare Safety Network Risk Models for Surgical Site Infections in Total Hip and Knee Replacements

Background. The National Healthcare Safety Network surgical site infections risk models for hip (HPRO) and knee (KPRO) replacement are intended for case-mix adjustment when reporting surgical site infection rates across institutions, but they are not validated in external data sets Objective. To evaluate the validity of HPRO and KPRO risk models and improvement in risk prediction with inclusion of information on morbid obesity and diabetes mellitus. Design. Retrospective cohort study. Patients. A single-center cohort of 21,941 hip and knee replacement procedures performed between 2002 and 2009. Methods. Discriminative ability was assessed using the concordance statistic (C statistic). Calibration was assessed using the Hosmer-Lemeshow goodness-of-fit tests. Results. The discrimination of HPRO was good, with a C statistic of 0.695 for surgical site infections and 0.749 for prosthetic joint infections. The discrimination of KPRO was worse than that of HPRO, with a C statistic of 0.592 for surgical site infections and 0.675 for prosthetic joint infections. Adding morbid obesity and diabetes mellitus to the HPRO and KPRO risk models modestly improved discrimination. There was no significant evidence of miscalibration based on the Hosmer-Lemeshow tests, but calibration of HPRO models appeared to be better than that of the KPRO models. Conclusions. HPRO performed better than the KPRO in predicting surgical site infections after hip and knee replacements. Both fared well in predicting prosthetic joint infections. Infect Control Hosp Epidemiol 2014;35(11):1323–1329
Intrinsic Nilpotent Approximation.

Abstract : This report is a preliminary version of work on an intrinsic approximation process arising in the context of a non-isotropic perturbation theory for certain classes of linear differential and pseudodifferential operators P on a minifold M. A basic issue is that the structure of P itself determines the minimal information that the initial approximation must contain. This may vary from point to point, and requires corresponding approximate state spaces or phase spaces. This approximation process is most naturally viewed from a seemingly abstract algebraic context, namely the approximation of certain infinite dimensional filtered Lie algebras L by (finite-dimensional) graded nilpotent Lie algebras.
Effects of microgravity on vestibular development and function in rats: Genetics and environment

Our anatomical and behavioral studies of embryonic rats that developed in microgravity suggest that the vestibular sensory system, like the visual system, has genetically mediated processes of development that establish crude connections between the periphery and the brain. Environmental stimuli also regulate connection formation including terminal branch formation and fine-tuning of synaptic contacts. Axons of vestibular sensory neurons from gravistatic as well as linear acceleration receptors reach their targets in both microgravity and normal gravity, suggesting that this is a genetically regulated component of development. However, microgravity exposure delays the development of terminal branches and synapses in gravistatic but not linear acceleration-sensitive neurons and also produces behavioral changes. These latter changes reflect environmentally controlled processes of development.
How a multidisciplinary team improved a process to attain positive patient outcome.

Abstract A case study approach will be used to demonstrate the effectiveness of a continuous quality improvement team designed to explore the process of preoperative medical record completeness. The goal of this team was to improve essential chart components (eg, electrocardiography, history and physical examination) required 48 hours before the date of surgery in an effort to facilitate optimum patient management and timely flow of patients to the operating room. When the 48-hour compliance rule is followed, the nurse reviewer has sufficient time to review all patient data and notify attending physicians or designees of any abnormalities. In essence, improving component compliance provides better quality care because patients are able to be assessed before surgery with enough time to solve any problems. (Insight - the Journal of the American Society of Ophthalmic Registered Nurses 2000;25:50–4.)
Conditional lysis ofEscherichia coli by the fusion of extracellular (STA) to periplasmic (LTB) enterotoxins: Apparent phenotypic suppression of lactose permease

The expression of a methanol-soluble, heat-stable enterotoxin (STA) fused to the B subunit of the heat-labile enterotoxin (LTB) at 35°C or higher temperatures caused strains ofEscherichia coli deficient in lactose permease to behave on indicator media as Lac+; however, at 33°C or lower temperatures the original Lac− phenotype of the host strains was maintained. The apparent phenotypic suppression oflacY was shown to be due to lysis of a fraction of the bacteria and the consequent release of activeβ-galactosidase to the culture supernatant. After incubation at 37°C for 1 h, the cultures were committed to lyse. Plasmid and chromosomal mutants that do not show this phenotype were isolated by selecting Lac− colonies at the unpermissive temperature. The mutations on the plasmids were localized in both the heat-stable and the heat-labile enterotoxin genes. Chromosomal mutants that show normal levels ofβ-galactosidase and fused toxins have also been isolated.
987-102 Proximal Flow Convergence Calculation of Forward Flow and Valve Area of Normal Mitral Prostheses: An Intraoperative Validation

We have previously shown in vitro that the proximal flow convergence method (FC) can be used to calculate flow through larger orifices such as normal prosthetic heart valves. To validate FC clinically, we performed intraoperative transesophageal echocardiography on 22 patients (mean age 63 ± 8 yrs, 64% female) undergoing mitral valve replacement with St Jude valve (n = 17) or Carpentier-Edwards valve (n = 5). For St Jude prostheses, peak velocities and velocity integrals through the center (Vc and TVIc, respectively) and side (Vs and TVIs) orifices were interrogated separately with CW Doppler. As our in vitro model suggested about 80% of flow occurred through the side orifices, the corrected peak Velocity (Vo) is given by Vo = 0.8Vs + 0.2Vc and the corrected velocity integral (TVIo) by TVIo = 0.8TVIs + 0.2 TVIc. The flow rate (Q) was calculated by Q = 2πr2Va where Va is the aliasing velocity. Q was multiplied by Vo/(Vo-Va), a previously validated factor, to account for flattening of isotachs near the prosthetic orifice. Results Cardiac output (CO) calculated by (Qc*TVIo/Vo)*HR showed good correlation with thermodilution CO (Range 3.3–8.1 I/min, y = 0.87x + 0.67, r = 0.9, p l 0.001, ΔCO = -0.02 ± 0.5 I/min). Effective prosthetic orifice area (EOA) of St Jude valves, given by Qc/Vo, correlated well with geometric orifice area (GOA) from the manufacturers (r = 0.7, p = 0.002, y = 1.42x + 1.47). However, calculated EOA is significantly smaller than the GOA (ΔMVA = -2.23 ± 0.49 cm2, p l 0.01) Conclusions The proximal flow convergence method can give reliable in vivo estimates of 1) forward flow through normal mitral prostheses and 2) EOA of St Jude valves. The EOA of St Jude valve in vivo is significantly smaller than its GOA.
Severe winds in the DFW microburst measured from two aircraft

Advanced analytical methods are applied to the digital flight data and Air Traffic Control radar records from two airliners, Delta flight 191 and American flight 539, that penetrated a microburst at the Dallas/Ft. Worth airport on August 2, 1985. The results for Delta 191 (which crashed) show that the aircraft encountered a strong downburst followed by a strong outflow accompanied by large and rapid changes in the vertical wind. The rapid changes in the vertical wind detected near the ground are attributed to vortex-induced turbulence. The next following aircraft, American 539, made a go-around 110 sec after Delta 191 and traversed the microburst at an altitude of about 2500 ft above the ground. The measured winds during this go-around indicate a broad pattern of downflow in the microburst, with regions of upflow at the extreme edges. The combined results indicate a microburst that was increasing in size with vortex-induced turbulence embedded in a strong outflow near the ground. These wind measurements provide a realistic description of the microburst wind environment that can be used in simulator studies and pilot training, and provide a standard of comparison for ongoing experiments and modeling of microbursts involving vortex rings.
Self-trapping of incoherent bright and dark beams

This article covers recent theoretical and experimental observations of self-trapping incoherent bright and `dark' beams, or bright and dark incoherent spatial solitons.
Inverted hysteresis loops in CoO-based multilayers

Abstract We have observed inverted hysteresis loops in a number of multilayer [Co-O]/Cu and [Co-O]/Al multilayers. In this phenomenon, the forward and reverse branches of a hysteresis loop are shifted along the magnetic field axis in such a way that they cross each other and we report the dependence of this phenomenon on magnetic layer thickness. In many cases the Cu or Al layer is thick enough that interlayer interactions between magnetic layers are not possible. It is suggested that interface exchange between Co and Co-O phases within the magnetic layer is important in these multilayers and that this phenomenon is closely related to shifted hysteresis loops which are also produced by interface exchange. We do not find this behavior in nominally homogeneous Co-O films indicating that the multilayer nature of the material is important. A two-phase model is presented which is able to qualitatively explain some of the observed results.
Oxidative phosphorylation in fractionated bacterial systems IV. Enzymic formation of reduced intermediates from vitamin K1

Abstract Two reduced intermediates of vitamin K 1 formed enzymically under anaerobic conditions by extracts of Mycobacterium phlei have been trapped by acetylation. The isolated acetyl derivative of one of the intermediates was identical to the diacetate of vitamin K 1 while the other was similar to synthetic naphthotocopherol (naphthochromanol) monoacetate. The unacetylated compounds which accumulate have similar absorption characteristics; however, they can be distinguished since on direct extraction of the enzymic reaction mixture with ether the naphthohydroquinone is spontaneously oxidized. Thus the naphthotocopherol-like compound can be measured and isolated in the absence of a trapping agent. The subcellular distribution and properties of the naphthoqiunone-chromanol-forming enzyme are described. The enzymically formed compound is reoxidized to vitamin K 1 with the release of inorganic phosphate. This intermediate may play a role in oxidative phosphorylation since it serves as an electron donor and ATP is formed.
The adaptive capacity of fishery management systems for confronting climate change impacts on marine populations

Global climate change will affect the abundance, distribution, and life history timing of many exploited marine populations, but specific changes are difficult to predict. Management systems in which harvest strategies and tactics are flexible in responding to unpredictable biological changes are more likely to succeed in maintaining productive populations. We explore the adaptability of fisheries management systems in relation to oceanic warming rates by asking how two important management characteristics vary with temperature changes for >500 stocks. (1) Harvest control rules, a framework for altering fishing pressure in response to changes in the abundance of targeted species (primarily due to fishing), may provide the capacity for harvest policies to change in response to climate-driven abundance declines also. (2) Seasonal openings with flexible dates that involve in-season monitoring may allow managers to better respond to possible changes in the timing of life-history periods like spawning to prevent fishing seasons falling out of sync with species’ phenology. Harvest control rules were widely used across industrialized fisheries including in regions that experienced relatively high oceanic warming rates, but after controlling for regional factors we found no association between ocean warming and the use of harvest control rules. Flexible-date seasonal openings were rare compared to fixed-date seasonal openings, but tended to occur in areas with the greatest warming rates while fisheries without seasonal closures tended to occur in areas with the least observed temperature changes. We found no consistent evidence of recent ocean warming effects on the current biomass or exploitation rates relative to management targets of 241 assessed marine populations. Together, these results suggest that the oceanic areas expected to have the greatest climate impacts on populations do at least tend to contain fisheries that demonstrate the potential for adaptability to unpredictable climate impacts.
Mirativity in Tsafiki

Le tsafiki, langue barbacoa parlee en Equateur, presente une structure complexe marquee par un mode mediatif et une mirativite. La mirativite encode le statut de la proposition concernant la structure des connaissances generales du locuteur. Ainsi, une situation immediate qui n'est pas facilement assimilee parce qu'elle ne correspond pas aux attentes du locuteur, recoit un marquage special dans la proposition qui encode l'evenement ou l'etat. La mirativite semble universelle meme si elle est marquee grammaticalement par des procedes differents selon les langues. L'A. etudie les similarites de structures entre le tsafiki et le tibetain de Lhasa. Puis il decrit l'interaction entre les marques du miratif avec differentes classes semantiques verbales en tsafiki. Enfin, il discute de l'interaction entre mode mediatif et mirativite
Chemical vapor deposition of novel electronic materials from carbon disulfide

An organic amorphous semiconductor with unusual electrical switching capability has been synthesized by the direct decomposition of carbon disulfide. Metallic black highly conducting (above 102 Ω−1 cm−1) thin films of approximate composition C3S have been prepared by the simple passage of dilute carbon disulfide vapors over an incandescent tungsten filament. Film growth rates greater than 10 μmh−1 are observed. The coatings are hard, adherent on a wide variety of substrates, thermally stable, and remarkably inert to all but the most severe mineral acid digestion. The carbon sulfide solids behave like varistors, following Ohm's law over many decades of current up to a threshold voltage, typically 1–10 V, beyond which the current surges, independent of applied voltage. The threshold voltage is uniquely temperature dependent, reaching a maximum as the temperature is reduced from room temperature, then decreasing once again at cyrogenic temperatures.
Ketose reductase activity in developing maize endosperm.

Ketose reductase (NAD-dependent polyol dehydrogenase EC 1.1.1.14) activity, which catalyzes the NADH-dependent reduction of fructose to sorbitol (d-glucitol), was detected in developing maize (Zea mays L.) endosperm, purified 104-fold from this tissue, and partially characterized. Product analysis by high performance liquid chromatography confirmed that the enzyme-catalyzed reaction was freely reversible. In maize endosperm, 15 days after pollination, ketose reductase activity was of the same order of magnitude as sucrose synthase activity, which produces fructose during sucrose degradation. Other enzymes of hexose metabolism detected in maize endosperm were present in activities of only 1 to 3% of the sucrose synthase activity. CaCl2, MgCl2, and MnCl2 stimulated ketose reductase activity 7-, 6-, and 2-fold, respectively, but had little effect on NAD-dependent polyol dehydrogenation (the reverse reaction). The pH optimums for ketose reductase and polyol dehydrogenase reactions were 6.0 and 9.0, respectively. Km values were 136 millimolar fructose and 8.4 millimolar sorbitol. The molecular mass of ketose reductase was estimated to be 78 kilodaltons by gel filtration. It is postulated that ketose reductase may function to metabolize some of the fructose produced during sucrose degradation in maize endosperm, but the metabolic fate of sorbitol produced by this reaction is not known.
Two-key concurrent responding: response-reinforcement dependencies and blackouts.

Two-key concurrent responding was maintained for three pigeons by a single variable-interval 1-minute schedule of reinforcement in conjunction with a random number generator that assigned feeder operations between keys with equal probability. The duration of blackouts was varied between keys when each response initiated a blackout, and grain arranged by the variable-interval schedule was automatically presented after a blackout (Exp. I). In Exp. II every key peck, except for those that produced grain, initiated a blackout, and grain was dependent upon a response following a blackout. For each pigeon in Exp. I and for one pigeon in Exp. II, the relative frequency of responding on a key approximated, i.e., matched, the relative reciprocal of the duration of the blackout interval on that key. In a third experiment, blackouts scheduled on a variable-interval were of equal duration on the two keys. For one key, grain automatically followed each blackout; for the other key, grain was dependent upon a response and never followed a blackout. The relative frequency of responding on the former key, i.e., the delay key, better approximated the negative exponential function obtained by Chung (1965) than the matching function predicted by Chung and Herrnstein (1967).
Plant Adaptation in an Ecosystem Context: Effects of Defoliation, Nitrogen, and Water on Growth of an African C4 Sedge

Clones of a C4 sedge, Kyllinga nervosa Steud., from a semiarid location in the Serengeti region of Tanzania were propagated vegetatively and grown at 12-h photoperiods, 30C maximum daytime temperature and 15? minimum nighttime temperature, simulating conditions at the native site. Clipping height, clipping frequency, nitrogen concentration of the nutrient medium, and watering frequency were varied in an unbalanced factorial experiment. Plants were harvested after 5 mo of sustained treatment. Each yield component was principally regulated by a different environmental factor. Yield to grazers (amount clipped off) was controlled by nitrogen supply, yield to producers (residual biomass) was controlled by water, and yield to decomposers (litter and standing dead) was controlled by clipping height and nitrogen. Plant growth was stimulated by defoliation. Plants over- compensated for amounts removed at moderate defoliation and high nitrogen, undercompensated at severe defoliation, and just compensated under other conditions. Therefore, increments of energy flow to grazers can be additive in ecosystem budgets due to compensatory growth of affected plants. The most important mechanisms accounting for compensatory growth of K. nervosa were activation of plant meristems and stimulated rates of leaf elongation in defoliated plants. Allocation of residual plant biomass to various organs was virtually independent of environment, indicating genetic control of physiological processes tending to balance allocation over a broad environmental range.
Amorphous Hydrogenated Semiconductors

Semiconducting thin films are produced in plasma and CVD reactors and are commercially useful materials because of a ubiquitous presence of hydrogen, a low density of defects, and electro-optical properties which vary systematically with composition. However, little is known about how variations in fundamental growth parameters produce concomitant changes in film properties, particularly hydrogen incorporation. The reason for this gap in knowledge derives partly from the lack of adequate structural probes of disordered materials. In recent years nuclear magnetic resonance spectroscopy (NMR) has emerged as a powerful probe of the microstructure of amorphous semiconductors. I will discuss recent developments in the application of NMR to studies of amorphous hydrogenated semiconductors, and interpret these results in terms of the chemistry and physics of the growth process.
On the morning commute problem in a corridor network with multiple bottlenecks: Its system-optimal traffic flow patterns and the realizing tolling scheme

There have been numerous studies of the morning commute problem in a network with a single route or parallel routes with a single bottleneck on each route. Most congested networks, however, often contain more than one congestion spot along each route. In such networks, it is usually difficult to derive analytically their system-optimal traffic patterns and the tolls that realize them. In this paper, we study the morning commute problem in such a network with certain special topological features – a freeway with multiple entry/exit ramps and a surface street grid with large capacities. For this type of networks, we investigated the basic characteristics of their optimal dynamic traffic patterns and the corresponding tolling scheme, for which a graphical solution procedure was also developed. In this network, we found that at system-optimum: (1) the aggregate traffic flow on the freeway has a staircase temporal profile, and piecewise linear dynamic tolls can be imposed on a subset of ramps to achieve it; (2) among all the off-ramps in use, the ones closer to the destination are being tolled longer with higher maximum toll charges than the ones farther away from the destination; and (3) among all the on-ramps in use, the ones with larger cumulative volume-to-capacity ratios are being tolled longer with higher maximum toll charges. Some practical implications of these findings to corridor traffic management were also discussed.
Characteristics Associated With Low Food and Fluid Intake in Long-Term Care Residents With Dementia

This article describes the prevalence, assessment, and treatment of, as well as characteristics associated with, the food and fluid intake of 407 residents with dementia in 45 assisted living facilities and nursing homes. Overall, 54% of observed residents had low food intake, and 51% had low fluid intake. Staff monitoring of residents, having meals in a public dining area, and the presence of noninstitutional features were each associated with higher food and fluid intake.
Receptors and Second Messengers in Cell Function and Clinical Disorders

Cellular receptors provide an important mechanism for transmitting hormonal, immunologic, and neurophysiological information between cells. Originally defined in terms of physiological responses, receptor-mediated mechanisms are being defined in increasingly greater detail at pharmacological, physiological, and biochemical levels. Direct binding studies with a profusion of radioligands have identified binding sites in a host of tissues. It is now recognized that these binding sites are not inert entities but undergo a variety of regulatory processes in response to alterations in the hormonal milieu. Changes in receptor occupancy modify receptor-linked functions such as enzymic activity (i.e., adenylate cyclase) or ion flux. The resulting changes in “second messengers,” such as cAMP or cytosolic calcium, modulate the function of additional effector systems (e.g., protein kinase or calmodulin-linked enzymes). Phosphorylation or other modifications of specific cellular substrates change cellular function in ways characteristic of the target tissue.