cssi/SciSciGPT-SciSciNet huggingface dataset:
Human DNA Polymerase ν Catalyzes Correct and Incorrect DNA Synthesis with High Catalytic Efficiency

DNA polymerase ν (pol ν) is a low fidelity A-family polymerase with a putative role in interstrand cross-link repair and homologous recombination. We carried out pre-steady-state kinetic analysis to elucidate the kinetic mechanism of this enzyme. We found that the mechanism consists of seven steps, similar that of other A-family polymerases. pol ν binds to DNA with a Kd for DNA of 9.2 nm, with an off-rate constant of 0.013 s−1and an on-rate constant of 14 μm−1 s−1. dNTP binding is rapid with Kd values of 20 and 476 μm for the correct and incorrect dNTP, respectively. Pyrophosphorylation occurs with a Kd value for PPi of 3.7 mm and a maximal rate constant of 11 s−1. Pre-steady-state kinetics, examination of the elemental effect using dNTPαS, and pulse-chase experiments indicate that a rapid phosphodiester bond formation step is flanked by slow conformational changes for both correct and incorrect base pair formation. These experiments in combination with computer simulations indicate that the first conformational change occurs with rate constants of 75 and 20 s−1; rapid phosphodiester bond formation occurs with a Keq of 2.2 and 1.7, and the second conformational change occurs with rate constants of 2.1 and 0.5 s−1, for correct and incorrect base pair formation, respectively. The presence of a mispair does not induce the polymerase to adopt a low catalytic conformation. pol ν catalyzes both correct and mispair formation with high catalytic efficiency.
The Role of the Vibration Signal during Nest-Site Selection by Honey Bee Swarms

The vibration signal may influence nest-site selection by honey bee swarms by enhancing scouting and recruitment. We investigated this hypothesis by comparing (1) the number of nest sites and the distances communicated by nest-site dancers on swarms from which vibrators were and were not removed and (2) the behavior of scouts visiting higher-quality (HQ) and lower-quality (LQ) nest boxes. The removal of vibrators from swarms did not alter the number of nest sites investigated, the distances traveled to nest sites, or the time required to select a new nest cavity. In contrast, vibrator removal tripled the time required for swarms to achieve liftoff after a cavity had been selected, although all swarm eventually became airborne and moved to a new site. About 14% of the scouts that visited the HQ and LQ nest boxes performed vibration signals; however, nest-box quality did not influence the tendency to produce the signal or intermix vibration signals and recruitment dances. However, we did find a significant, positive correlation between overall levels of vibration signal activity and nest-site recruitment during the house-hunting process. When viewed in concert, our results suggest that the vibration signal contributes to the house-hunting process by operating in a non-specific manner that may enhance scouting and recruitment in general during nest-site selection and facilitate rapid swarm liftoff after a new nest site has been chosen. The vibration signal is therefore a component in the cascade of communication signals that orchestrate house-hunting and colony relocation decisions.
Voice coil actuators for human-robot interaction

The growing field of human-robot interaction (HRI) demands robots that move fluidly, gracefully, compliantly and safely. This paper describes our recent work in the design and evaluation of long-travel voice coil actuators (VCAs) for use in robots intended for interacting with people. The basic advantages and shortcomings of electromagnetic actuators are discussed and evaluated in the context of human-robot interaction, and are compared to alternative actuation technologies. Voice coil actuators have been chosen for their controllability, ease of implementation, geometry, compliance, biomimetic actuation characteristics, safety, quietness, and high power density.
Can advising lead to meaningful relationships

Schools have increasingly implemented advising programs as a means of linking students with caring adults. Although this approach is promising, its success depends on adequate funding; the full commitment of administration, staff, and parents; and a thoughtful definition of the procedures for achieving the goals.
Allergy increases susceptibility to otitis media with effusion in a rat model

To investigate the possible relationship between allergy and otitis media with effusion (OME), we investigated the hypothesis that allergen presentation to the middle ear causes functional disruption of the eustachian tube predisposing to the development of OME. Thirteen of 19 Brown-Norway rats were sensitized to ovalbumin, and the remaining 6 served as nonallergic controls. To mimic subclinical exposure to allergen, we transtympanically injected ovalbumin at a dose (0.01 mg) that produced no changes detectable by otologic examination. Next, both allergic and nonallergic rats were exposed to transtympanic injection of either low-dose (10 microg/mL) or high-dose (100 microg/mL) lipopolysaccharide to simulate bacterial exposure. The allergic rats were found to have larger middle ear effusions when exposed to high-dose lipopolysaccharide as compared with the nonallergic controls. This response could be inhibited by diphenhydramine. We conclude that allergen presentation to the middle ear of allergic rats causes eustachian tube dysfunction predisposing to OME.
Design and realization of transversal microwave bandpass filters

A bandpass microwave filter design method utilizing transversal signal flow theory is discussed. The realization of finite zeros of transmission is achieved through a supplementary network. A wealth of filtering functions can be emulated by the effective combination of a transversal section cascaded to the supplementary. The composite filter offers steep passband edges with passband flatness. A sample filter is designed based upon the theory presented. Layout and junction effects were modeled in the final circuit. The fabricated microstrip structure was tested and performed within specifications. >
Cerebral Toxoplasmosis in a Patient on Methotrexate and Infliximab for Rheumatoid Arthritis

Cerebral toxoplasmosis is a rare disease predominantly found in immunocompromised hosts. However, cerebral toxoplasmosis has not been frequently described in association with the use of immunosuppressive medications. We herein report a case of cerebral toxoplasmosis in a 76-year-old Caucasian woman on methotrexate and infliximab for rheumatoid arthritis. The patient presented with right facial droop, slurred speech and difficulty walking. In addition to receiving methotrexate and infliximab and owning a cat, she had no other obvious risk factors. Imaging studies were not conclusive; however, brain biopsy confirmed the diagnosis. Serology was positive for anti-toxoplasma immunoglobulin G. Cerebral toxoplasmosis should be included in the differential diagnosis of patients under immunosuppressive medication who present with neurological manifestations.
An Intensified Storage Vidicon Camera for Finding and Guiding at the Telescope

Publisher Summary This chapter discusses an intensified storage vidicon camera for finding and guiding at the telescope. It is a great convenience at astronomical telescopes to use a television viewing system which can see faint objects directly. Integrations of several seconds are made to obtain an image of adequate signal to noise ratio and then the target is read out. The image is stored in a scan converter and is continuously read out to give a normal television video signal for display on standard monitors. In some systems very deep images are obtained by digitally adding several integrations to improve the signal to noise ratio. The intensifiers are 25 mm electrostatically focused diodes. The vidicon is protected against deflection circuit failure by sampling the voltage developed across the current sense resistors in series with the deflection coils. This signal is amplified and used to trigger retriggerable one-shots upon retrace.
Prevención de la desnaturalización proteica en actomiosina de jurel (Trachurus murphyi) durante su almacenamiento en congelación/Prevention of protein denaturation of jack mackerel actomyosin (Trachurus murphyi) during frozen storage

Protein denaturation during frozen storage at -18 "C for 16 weeks was studied in jack mackerel (Trachurus murphyi) actomyosin. The cryoprotective effect of different additives was evaluated at a level of 8°/, (w/w): sucrose/sorbitol (1:1), maltodextrin 25 DE, milk whey and sodium lactate. The results were compared with a control sample without additives. The decrease in protein solubility and calcium ATPase activity confirmed that protein denaturation occurred both during the freezing process and during frozen storage. Higher losses were observed after one week at -18 °C. Sucrose/sorbitol and maltodextrin 25 DE were the best cryoprotectants. DSC thermograms showed two endothermic transitions with Tmax at 46.8 °C and 68.9 °C assigned to myosin and actin respectively. The best cryoprotective effect was achieved with sucrose/sorbitol and maltodextrin 25 DE. These additives showed Tmax and ΔH values for myosin and actin significantly higher than the control.
Transverse undulator spectra and polarization profiles

Abstract Extensive modeling of single-electron undulator spectra has been carried out at SSRL. In this paper, we display several multiparameter plots of intensity and polarization for values of K in the undulator and low wiggler regimes. A brief summation of the properties of angle-integrated spectra is also given.
Transient effects in InAs/GaAs quantum-dot detectors under low-temperature and low-background conditions

In the presence of a time-dependent external source such as a bias electric field or an incident optical flux, electrons in quantum well and quantum dot devices experience non-adiabatic transport through the barrier layer between two adjacent quantum wells or quantum dots. This non-adiabatic transport process induces charge density fluctuations, resulting in several transient phenomena. When a time-dependent electric field is applied to the system, a dynamical breakdown (i.e., the dark current is dominated by a dielectric displacement current) of the quantum well or quantum dot photodetector is observed. If a chopped time-dependent optical flux is incident on either system, a dynamical drop in the photo-responsivity with increasing chopping frequency is also observed.
Application-independent testing of FPGA interconnects

We present a new automatic test-configuration-generation technique for application-independent manufacturing testing of the interconnection network of static-random-access-memory-based field programmable gate arrays (FPGAs). This technique targets detection of open and bridging faults in the wiring channels and programmable switches in the interconnects. Experimental results on Xilinx Virtex FPGAs show that very few test configurations are required to cover stuck-open, stuck-closed, open, and bridging faults in the interconnects.
Extrachromosomal DNA in eucaryotes

Eucaryotic extrachromosomal DNAs have been organized into four major classes: (1) Organelle DNAs, (2) plasmid DNAs, (3) amplified genes, and (4) intermediates and/or by-products of DNA transpositions and rearrangements. In this review some of the relatively well-characterized members of each class are described; it is suggested that many of them reflect the complexity and plasticity of eucaryotic genomes.
Computer model for glucose-limited growth of a single cell of Escherichia coli B/r-A.

A computer model is described which is capable of predicting changes in cell composition, cell size, cell shape, and the timing of chromosome synthesis in response to changes in external glucose limitation. The model is constructed primarily from information on unrestricted growth in glucose minimal medium. The ability of the model to make reasonable quantitative predictions under glucose-limitation is a test of the plausibility of the basic biochemical mechanisms included in the model. Such a model should be of use in differentiating among competing hypotheses for biological mechanisms and in suggesting as yet unobserved phenomena. The last two points are illustrated with the testing of a mechanism for the control of the initiation of DNA synthesis and predictions on cell-width variations during the division cycle.
Parthenogenic blastocysts derived from cumulus-free in vitro matured human oocytes.

Background Approximately 20% of oocytes are classified as immature and discarded following intracytoplasmic sperm injection (ICSI) procedures. These oocytes are obtained from gonadotropin-stimulated patients, and are routinely removed from the cumulus cells which normally would mature the oocytes. Given the ready access to these human oocytes, they represent a potential resource for both clinical and basic science application. However culture conditions for the maturation of cumulus-free oocytes have not been optimized. We aimed to improve maturation conditions for cumulus-free oocytes via culture with ovarian paracrine/autocrine factors identified by single cell analysis. Methodology/Principal Finding Immature human oocytes were matured in vitro via supplementation with ovarian paracrine/autocrine factors that were selected based on expression of ligands in the cumulus cells and their corresponding receptors in oocytes. Matured oocytes were artificially activated to assess developmental competence. Gene expression profiles of parthenotes were compared to IVF/ICSI embryos at morula and blastocyst stages. Following incubation in medium supplemented with ovarian factors (BDNF, IGF-I, estradiol, GDNF, FGF2 and leptin), a greater percentage of oocytes demonstrated nuclear maturation and subsequently, underwent parthenogenesis relative to control. Similarly, cytoplasmic maturation was also improved as indicated by development to blastocyst stage. Parthenogenic blastocysts exhibited mRNA expression profiles similar to those of blastocysts obtained after IVF/ICSI with the exception for MKLP2 and PEG1. Conclusions/Significance Human cumulus-free oocytes from hormone-stimulated cycles are capable of developing to blastocysts when cultured with ovarian factor supplementation. Our improved IVM culture conditions may be used for obtaining mature oocytes for clinical purposes and/or for derivation of embryonic stem cells following parthenogenesis or nuclear transfer.
Efficient anonymity-preserving data collection

The output of a data mining algorithm is only as good as its inputs, and individuals are often unwilling to provide accurate data about sensitive topics such as medical history and personal finance. Individuals maybe willing to share their data, but only if they are assured that it will be used in an aggregate study and that it cannot be linked back to them. Protocols for anonymity-preserving data collection provide this assurance, in the absence of trusted parties, by allowing a set of mutually distrustful respondents to anonymously contribute data to an untrusted data miner.To effectively provide anonymity, a data collection protocol must be collusion resistant, which means that even if all dishonest respondents collude with a dishonest data miner in an attempt to learn the associations between honest respondents and their responses, they will be unable to do so. To achieve collusion resistance, previously proposed protocols for anonymity-preserving data collection have quadratically many communication rounds in the number of respondents, and employ (sometimes incorrectly) complicated cryptographic techniques such as zero-knowledge proofs.We describe a new protocol for anonymity-preserving, collusion resistant data collection. Our protocol has linearly many communication rounds, and achieves collusion resistance without relying on zero-knowledge proofs. This makes it especially suitable for data mining scenarios with a large number of respondents.
Attitude study of on-line terminal operators on work-station arrangements

A questionnaire survey was conducted covering 75 on-lineterminal operators at a large gas utility. They were asked to give preference ratings to alternative arrangements with regard to panelling, seating, background music, and the locationof a terminal on the desk. The majority of the respondents preferred an open space layout to layouts with some panels, and some background music to no music. These results are in conformity with the findings of most past studies. As to seating arrangements, they gave the highest preference to a random arrangement made independent of the employee's sex or sensority. With respect to the location of a terminal, the lefthand side of the operator was rated highest by about half of the respondents, and the center of the desk by one quarter of them.
A thermal study of the trifluoroacetates and pentafluoropropionates of praseodymium, samarium and erbium

Abstract Several lanthanide salts of trifluoroacetic and pentafluoropropionic acid have been prepared and characterized. Powder X-ray diffraction and thermal studies have shown the compounds to be isomorphous within their respective series and to dehydrate in definite steps. Decomposition was found to be exothermic resulting in the formation of LnF 3 , LnOF and Ln 2 O 3 at various stages. The volatile decomposition products were identified by IR analysis and found to consist of CO, CO 2 , CF 3 COF, (CF 3 CO) 2 O, CF 3 CF 2 COF and (CF 3 CF 2 CO) 2 O. Quantitative studies revealed the general reaction scheme for the trifluoroacetates to proceed as follows: secondary decomposition produces Similar studies on the pentafluoropropionates were complicated by what appeared to be a carbon-to-carbon cleavage resulting in mixed products of CF 3 COF and CF 3 CF 2 COF.
The measurement of ion flow velocity by Mach probes in unmagnetized plasmas

Summary form only given. The measurement of ion flow in unmagnetized plasmas is performed using two Mach probes, one is a planar Mach probe and the other is spherical. The planar Mach probe consists of two single sided planar Langmuir probes back to back with an insulator between them. The spherical Mach probe, which was inspired by Hutchinson's numerical calculation, consists of a conducting sphere that has two conducting probe tips, insulated from the sphere and mounted at /spl theta/=0/spl deg/ and 180/spl deg/ with respect to the flow direction. The experiments are performed in a double-plasma device for ion flow velocity v/sub f/ up to 4.5 c/sub s/, where c/sub s/ is the sound speed, and along a presheath in a multi-dipole DC plasma for v/sub f/ < 1.0 c/sub s/ with Argon pressure ranging from 0.1 to 1 mTorr and plasma density range of 10/sup 7//spl sim/10/sup 10/ cm/sup -3/. The laboratory plasma in the, presheath was limited to T/sub i/, <0.1 T/sub e/ and v/sub f//spl les/1.0 c/sub s/. The measured super-sonic ion flow velocities are compared to the velocity from ion energy using an ion energy analyzer and single sided probes.
Physical Attractiveness, Age, And Body Type

Physical attractiveness is known to affect people's responses in a variety of situa tions. Although people willingly ascribe physical attractiveness to others, there has been little success in determining the facets of physical appearance which influence judged physical attractiveness. Researchers have found that, when asked, people will report that a model's face and weight are two characteristics which seem to affect attractiveness judgments. However, it is known that people are not accurate at reporting what influences them. This research was designed to measure people's responses to variations in physical attractiveness as a function of a facial characteristic (age) and a characteristic related to weight (body type or size). Sixty college-aged participants viewed and responded to black and white photos of female models, who systematically varied in age and body type. Sub jects guessed each model's attitude on a variety of issues and then judged each model's attractiveness. Analysis of variance revealed main effects for both age and body type on attractiveness, such that younger models were seen as more attractive than older models and that thinner models were seen as more attractive than heavier models. Main effects were also found for age and body type on assumed attitude similarity which indicates that age and body type of model function analogously to judged physical attractiveness. Clearly, age and body type are important components of physical attractiveness and avenues for re search are suggested.
Multiscale document segmentation using wavelet-domain hidden Markov models

We introduce a new document image segmentation algorithm, HMTseg, based on wavelets and the hidden Markov tree (HMT) model. The HMT is a tree-structured probabilistic graph that captures the statistical properties of the coefficients of the wavelet transform. Since the HMT is particularly well suited to images containing singularities (edges and ridges), it provides a good classifier for distinguishing between different document textures. Utilizing the inherent tree structure of the wavelet HMT and its fast training and likelihood computation algorithms, we perform multiscale texture classification at a range of different scales. We then fuse these multiscale classifications using a Bayesian probabilistic graph to obtain reliable final segmentations. Since HMTseg works on the wavelet transform of the image, it can directly segment wavelet-compressed images, without the need for decompression into the space domain. We demonstrate HMTseg's performance with both synthetic and real imagery.
Λb semileptonic decay form factors for mc

Abstract The six form factors which characterize the matrix elements of the axial vector and vector currents that occur in semileptonic Λ b → Λ c e v decay are expressible, to leading order, in terms of a single function of v′v, normalized at zero recoil. We show that including terms proportional to 1 m c , the form factors are still expressible in terms of a single function (whose normalization at zero recoil is known) and one dimensionful constant.
No more ‘soft’ science: Quantitative evaluation of collaboration effectiveness

Researchers and evaluators are often asked to give quantitative measures on topics that do not easily lend themselves to such measurement. Collaboration is one such topic: it is acknowledged to be a critical success factor for all kinds of organizations, but research and evaluation often lags because of the difficulty of measurement. This tutorial will introduce a range of quantitative methods for evaluating collaboration, on three levels: group-level experiments, micro-level measures (individuals), and macro-level measures (organizations.) I will walk participants through the methods where I have the most experience, and also mention a number of other methods, some very new, which may become increasingly valuable.
The HCN gene family: molecular basis of the hyperpolarization-activated pacemaker channels.

: The molecular basis of the hyperpolarization-activated cation channels that underlie the anomalous rectifying current variously termed Ih, Iq, or If is discussed. On the basis of the expression patterns and biophysical properties of the newly cloned HCN ion channels, an initial attempt at defining the identity and subunit composition of channels underlying native Ih is undertaken. By comparing the sequences of HCN channels to other members of the K channel superfamily, we discuss how channel opening may be coupled to membrane hyperpolarization and to direct binding of cyclic nucleotide. Finally, we consider some of the questions in cardiovascular physiology and neurobiology that can be addressed as a result of the demonstration that Ih is encoded by the HCN gene family.
Identification of human H-Y antigen and its testis-organizing function.

In a mutational absence of the proposed plasma membrane anchorage sites of H-Y antigen, the original pseudodiploid line of β+2microglobulin (—), HLA (—) Daudi human male Burkitt lymphoma cells proved themselves incapable of stably maintaining H-Y antigen on their plasma membrane. Instead, H-Y antigen was excreted into the culture medium. Human H-Y antigen so excreted was identified as a series of polymers of molecular weight (MW) 18,000 subunit formed by interchain disulfide bridges. MW 18,000 H-Y antigen subunit and other equally hydrophobic protein subunits excreted by Daudi cells were characterized by half-lives longer than 20 hours. Human H-Y antigen excreted by Daudi demonstrated a specific binding affinity toward unoccupied gonad-specific H-Y receptor sites residing on the plasma membrane of XX bovine embryonic gonadal cells, and this interaction induced the precocious testicular transformation in XX bovine embryonic indifferent gonads. In this experiment reported here, the variant pseudotetraploid line of Daudi produced an altered form of MW 18,000 subunit which was no longer capable of polymerizing via interchain disulfide bridges. Most of the altered H-Y antigen subunit remained on the plasma membrane, but a small amount of it was excreted and demonstrated no binding affinity toward unoccupied gonad-specific H-Y receptor sites. However, this altered, monomeric H-Y antigen subunit still readily absorbed the male-specific cytotoxicity contained in H-Y antibody.
Thin-layer chromatography of substituted glycosides.

Abstract A thin-layer chromatographic procedure useful for the separation of various derivatized carbohydrates is described. The method is also useful for the separation of the anomeric α- and β- d -glycosides of partially or completely derivatized carhydrates. The method has been used to monitor the alkylations of benzylated carbohydrates; it is shows no decrease in resolution even in the presence of salts. The method involves irrigation of Silica Gel H with petroleum ether (30–60°)-acetone mixtures in volume to volume ratios of 100:15 to 100:40.
The hydrologic effects of urban land use: a case study of the Little Miami River Basin

Abstract This paper examines the impacts of urbanization on the Little Miami River Basin. Flood frequencies of an urbanizing town (Milford) and a rural area (Perintown) were analyzed based on the historical discharge data. Water samples were collected for chemical analyses and bioassays were conducted to determine the effects of runoff on seed germination and root development. The results of this study indicate that watershed urbanization has caused more frequent floods, poorer water quality and vegetation growth.
Report of the Chicago Discussion Group

∗At the request of the Program and Research Committee of the Religious Education Association, discussion groups were organized at various points to study the topic suggested by the heading of this section. Two groups, one at Chicago under the chairmanship of Professor Bower, and the other at Chester, Pennsylvania, under the chairmanship of Professor Cole, carried through. Their written statements, together with a critique of Professor Cole's paper by Professor Smith of Duke University, are included here as they were read on the floor of the Pittsburgh convention. Professor Harner's paper was written in the light of convention discussion; Professor Soares’, several weeks before the Pittsburgh meetings.
A morphologic and statistical comparative study of small-cell carcinoma and non-Hodgkin's lymphoma in fine-needle aspiration biopsy material from lymph nodes.

Small-cell carcinoma (SmC) and high-grade non-Hodgkin's lymphoma (NHL) are aggressive neoplasms that require prompt diagnosis and treatment. An immediate diagnosis can be obtained using fine-needle aspiration biopsy (FNAB) material from lymph nodes (LNs), which are clinically or radiologically suspicious for tumor involvement. However, in aspirates from LNs, the cytologic distinction of SmC from NHL can be challenging. The purpose of this study was to evaluate the usefulness of various cytologic features that can be used during a rapid on-site evaluation to differentiate these two entities. Twenty-seven metastatic SmC and 50 NHLs cases diagnosed by FNAB of LNs were reviewed. All NHL diagnoses (neck, 29; abdomen, 9; axilla, 6; groin, 5; and parotid, 1) were confirmed with tissue sections, flow cytometry, or immunohistochemistry. These cases were classified as follicular, 21 (42%); diffuse large B cell, 13 (26%); small lymphocytic, 7 (14%); mantle cell, 4 (8%); anaplastic large cell, 2 (4%); and 1 each (2%), Burkitt, lymphoplasmacytic, and peripheral T-cell lymphomas. Immunochemistry confirmed the cytologic diagnoses of all SmC cases (neck, 16; mediastinum, 9; abdomen, 1; and axilla, 1) with either positive chromogranin or synaptophysin. All specimens were reviewed independently by three cytopathologists who were unaware of the original diagnoses. The presence and proportion of single (noncohesive) tumor cells, lymphoglandular bodies, nuclear fragments, paranuclear blue inclusions, nuclear molding, evenly dispersed fine-granular chromatin, crush artifact, and composition of cell clusters (monomorphic vs. polymorphic) were statistically evaluated. The presence of evenly dispersed fine-granular chromatin, paranuclear blue inclusions, and nuclear fragments was each statistically significant in differentiating SmC when compared with NHL (P < 0.01). The remaining features were not significant in distinguishing SmC from NHL in LN aspirates. The identification of distinct cytologic findings such as evenly dispersed fine-granular chromatin, paranuclear blue inclusions, and nuclear fragments can be a valuable aid to accurately diagnose and differentiate metastatic SmC from NHL in FNAB preparations from LNs. Diagn. Cytopathol. 2004;31:229–234. © 2004 Wiley-Liss, Inc.
Impurity effects in electron hole droplets

Abstract We use a simple model to describe the effects of impurities on the electron hole droplet emission spectrum. In this model, an attractive interaction between the droplet and impurities causes a decrease in droplet density and an increase in the droplet work function. The predictions of the model are in good agreement with experiment.
Isolation of a mutant strain of Pseudomonas sp. ATCC 31461 exhibiting elevated polysaccharide production

A mutant strain of the bacterium Pseudomonas sp. ATCC 31461 that exhibited elevated production of the polysaccharide gellan on glucose or corn syrup as a carbon source was isolated. Gellan production by the mutant strain was about twofold higher than its parent strain on glucose or corn syrup after 48 h of growth, and about 1.4-fold higher after 72 h. An increase in biomass production was not correlated with enhanced gellan synthesis by the mutant strain. The increased gellan production by the mutant strain on either carbon source resulted in an increase in its culture medium viscosity and the viscosity of the isolated polysaccharide produced by glucose-grown cells. No differences in the glucuronic acid content of the polysaccharides produced by the mutant and parent strains were observed.
Determination of adaptively adjusted coefficients for Hopfield neural networks utilizing the energy function

With its potential for parallel computation and general applicability, the Hopfield neural network has been investigated and improved by many researchers in order to extend its usefulness to various combinatorial problems. In spite of its success in several applications within different energy function formulations, determination of the energy coefficients has been based primarily on trial and error methods since no practical and systematic way of finding good values has been available preciously, although some theoretical analyses have been presented. In this paper, we present a methodical procedure which adaptively determines the energy coefficients leading to a valid solution as the network evolves. This method directly utilizes the value of each competing term in the energy function to balance the coefficients at each stage of the computation of the network. The advantage of this method is that the system itself controls the amount of energy which each term contributes to the total energy. To demonstrate the effectiveness of this approach, the N-Queens problem (a well known example of a constraint satisfaction problem) is studied and verified. Also, an inexpensive method for computation of the new energy level of each term at each stage of iteration is described based on incremental updating.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Sporol: A structure revision

Proton NMR studies suggest structure 2, and not 1, for sporol. Structure 1, formerly attributed to sporol, is designated neosporol.
Multiple endocrine neoplasia.

The MEN syndromes continue to be the focus of considerable interest and research. Since successful treatment requires early diagnosis, proper screening and follow-up of patients at risk is important. In the individual at risk for developing MEN IIa, annual screening should include measurement of the basal and stimulated plasma CT levels, and determination of plasma levels of calcium, PTH, and CEA. Twenty-four hour urine excretion rates of norepinephrine, epinephrine, metanephrine, dopamine, and VMA should also be obtained. It is our recommendation that this screening be continued through the third decade of life. Patients having thyroidectomy for MTC need to be tested annually for recurrent MTC and the development of adrenal medullary disease. All patients at risk for developing MEN IIb should be evaluated in a similar fashion. Recently, several groups using DNA linkage analysis have mapped the gene for MEN IIa to chromosome 10, althought the exact location of the gene is yet to be determined.50,51 Preliminary linkage studies have mapped the gene for MEN I to chromosome 11.52 The identification of the genes for MEN I and MEN II will greatly simplify the diagnosis of the disease and perhaps also the therapy of affected patients.
Effects of Timber Management on Pond-Breeding Salamanders

Abstract Pond-breeding salamanders spend most of their lives in forested habitat surrounding the vernal pools where they breed. Timber harvesting has been demonstrated to have negative impacts on salamander populations due to changes in soil temperature, soil compaction, and general degradation of habitat. However, little is known about how long it takes for harvested forest habitat to once again become suitable for salamanders. Questions also remain as to whether salamanders will use an area that has been harvested in recent years if an older intact forest area is available. We used drift fences and pitfall traps to capture adult spotted salamanders (Ambystoma maculatum) and marbled salamanders (A. opacum) migrating to 3 vernal ponds during their breeding seasons. The study area contained tracts of forest that were clear-cut 11–12 years prior to the study. All 3 ponds were surrounded by areas of clear-cut and intact forest and drift fences were placed in both habitat types. Similar numbers of spotted sal...
Mental stress and the cardiovascular system part I: Cardiovascular response to acute mental stress in normal subjects

Abstract In normal subjects, acute mental stress may alter baseline cardiovascular parameters. During this stimulation, blood pressure and heart rate commonly increase. Changes in peripheral vascular resistance are variable. Parameter responses during acute mental stress may be incorporated in the model of isotonic (dynamic or volume) exercise with increased blood pressure and decreased peripheral vascular resistance or in the model of isometric (static or pressure) exercise with increased blood pressure and increased peripheral vascular resistance. Sustained isotonic exercise such as jogging or swimming is generally considered healthful. In contrast, sustained isometric exercise such as weight lifting or snow shoveling is generally not considered healthful. Measuring peripheral vascular resistance may be important in distinguishing between healthful and unhealthful activities. In normal subjects, acute mental stress may also alter heart rate, double product (blood pressure × heart rate), cardiac output, stroke volume, forearm blood flow, left ventricular ejection fraction, and cardiac microcirculation. Studies in normal subjects have identified relationships between hostility and increased arousal, and blood pressure and heart rate increases. Failure to measure peripheral vascular resistance in these studies confounds full interpretation of the findings.
The Effectiveness of the E-Team Approach to Invention and Innovation*

Within the last decade, teamwork has become a well-known phenomenon in U.S. industry. Effective teamwork has led to an increase in productivity, a reduction in costs, a rise in employee involvement, and flattening of the organizational structure.1 This study examines students' attitudes and experiences towards working in teams, with particular attention paid to engineering students participating in entrepreneurial teams. The results of the study suggest that the students' attitudes and experiences were positive about working in teams. The majority of the students felt they were able to perform effectively in teams and thought that working in teams will be beneficial for preparing them for the workplace. Although students responded positively about their teamwork experience, only half of the students received team training. Some of the students felt indifferent about the usefulness of the team training sessions, which suggests that teamwork training needs to be improved.
308GA and TNFB polymorphisms in acute respiratory distress syndrome

The −308GA and TNFB1 /2 polymorphisms of the tumour necrosis factor genes have been associated with increased susceptibility to, and mortality in sepsis, although, prior studies are not consistent. Their role in acute respiratory distress syndrome (ARDS) has not been evaluated. The current authors hypothesised that the −308A allele and TNFB22 genotype would be associated with increased susceptibility to, and mortality in ARDS. The above hypothesis was investigated in a nested case-control study of 441 Caucasian controls and 212 cases admitted to an intensive care unit with sepsis, trauma, aspiration or hyper-transfusions. The −308A and TNFB1 alleles were in linkage disequilibrium. These polymorphisms were not associated with ARDS susceptibility on crude analysis. On subgroup analyses, they were associated with either increased or decreased odds of developing ARDS depending on whether the clinical risk for ARDS results in direct or indirect pulmonary injury. The −308A allele was associated with increased 60-day mortality in ARDS, with the strongest association found among younger patients. There was no association between the TNFB polymorphism and ARDS mortality. The − 308GA , but not the TNFB12 , polymorphism was associated with increased mortality in acute respiratory distress syndrome, but their association with acute respiratory distress syndrome susceptibility depended on the site of injury predisposing to acute respiratory distress syndrome.
Synthesis of hydrophilic and flexible linkers for peptide derivatization in solid phase.

Four N-Fmoc protected polyoxyethylene-based amino acid type linkers were designed and synthesized for peptide derivatization in solid phase. Three of them were obtained in a crystalline form. The crystallized linkers can be stored at 4 °C for 2 years without significant decomposition. Protocols for biotinylation and fluorescent labeling of peptides in solid phase were developed. The linkers also provide good ionization ability for single-bead mass spectrometry analysis of peptides.
Stage of development of leaf and tuber tissue of the potato plant influences the titer of potato virus M

The enzyme-linked immunosorbent assay (ELISA) was adapted for the detection of potato virus M (PVM). Detectability of PVM was influenced by the stage of plant growth and that of the plant part assayed. In young potato plants, one week prior to flowering, PVM titer was relatively high (0.77 A405nm units) in the basal leaves and barely detectable (0.09 A405 nm units) in the top leaves. In mature plants, two weeks prior to harvesting, top leaves contained more virus (0.34 A405 nm units) than middle (0.24 A405nm units) or basal leaves (0.15 A405 nm units). In rapidly growing tubers PVM content was higher (1.57 A405 nm units) than that in fully grown tubers (0.71 A405nm units) whereas the virus was not detectable in the mother tuber four weeks following planting. PVM was reliably detected when disks from intact leaves were substituted for leaf extracts as the test sample
Degradation of albumin by the renal proximal tubule cells and the subsequent fate of its fragments.

Degradation of albumin by the renal proximal tubule cells and the subsequent fate of its fragments. Background In view of recent reports of large amounts of albumin fragments present in normal urine we investigated the mechanism of albumin handling by the proximal tubule. Methods We injected 125 I-albumin intravenously in rats and measured the excretion of intact and degraded 125 I-albumin in the urine by trichloroacetic acid (TCA) precipitation. The excretion rate of intact 125 I-albumin was compared to that obtained by routine radioimmunoassay (RIA). Human proximal tubular HK-2 cells were used to characterize the albumin receptor and study the degradation of albumin to peptides, establish their size by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration chromatography, and determine the direction in which the degradation products are removed from the cell. Results Following injection of 125 I-albumin intravenously into rats we recovered large quantities of 125 I-albumin fragments in urine and determined that 98% was in a highly degraded form and only 2% was intact. Only the intact albumin could be detected by RIA. We observed similar results in the urine of ex vivo kidneys perfused with 125 I-albumin. We found that 125 I-albumin was taken up by HK-2 cells via a receptor, degraded in the lysosomes and the peptides exocytosed to both the apical and basolateral sides of the cells. Conclusion We conclude that normally the kidney degrades large amounts of albumin and that the degradation fragments appear in the urine. These findings are in sharp contrast with the established view that degraded albumin is completely reabsorbed into the blood stream.
Axillary lymph node metastases: screening with [F-18]2-deoxy-2-fluoro-D-glucose (FDG) PET.

PURPOSE: To evaluate [fluorine-18]2-deoxy-2-fluoro-D-glucose (FDG) positron emission tomography (PET) of the axilla as a screening test for detecting regional spread of breast cancer. MATERIALS AND METHODS: High-dose FDG PET of the axilla was successfully performed in 50 patients (age range, 36-79 years) with breast cancer before 52 axillary lymph node dissections. Two additional patients had scans that were uninterpretable because of intense myocardial activity that obscured the axilla. RESULTS: The sensitivity and negative predictive value were both 95%, the specificity was 66%, and the overall accuracy was 77%. The only false-negative PET scan was obtained in the largest patient, who had a low-quality scan. CONCLUSION: Patients with negative PET scans had such a low risk for axillary lymph node metastases that axillary dissection was not warranted. Patients with positive PET scans required dissection to confirm the presence and determine the number of positive lymph nodes. Had this algorithm been used ...
Effects of the space environment on the HST Wide Field Planetary Camera-I

The wide field planetary camera was launched onboard the Hubble Space Telescope in April 1990 and returned to earth during the HST first servicing mission in December 1993. We report on the ongoing examination of the returned hardware. In particular, a significant decline in performance at UV wavelengths in the exterior optics has been found and studied. This appears to be the result of polymerization of molecular contamination on the external optics by UV light reflected off the Earth's atmosphere. Some conlusions from a partial disassembly of the instrument and an examination of its filter elements are presented. We also discuss the effects of radiation on the CCD detectors during their stay in orbit. Radiation damage increased the numbers of hot pixels over time but had no other discernible effects on the performance of the CCDs.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Automation process for morphometric analysis of volumetric CT data from pulmonary vasculature in rats

With advances in medical imaging scanners, it has become commonplace to generate large multidimensional datasets. These datasets require tools for a rapid, thorough analysis. To address this need, we have developed an automated algorithm for morphometric analysis incorporating A Visualization Workshop computational and image processing libraries for three-dimensional segmentation, vascular tree generation and structural hierarchical ordering with a two-stage numeric optimization procedure for estimating vessel diameters. We combine this new technique with our mathematical models of pulmonary vascular morphology to quantify structural and functional attributes of lung arterial trees. Our physiological studies require repeated measurements of vascular structure to determine differences in vessel biomechanical properties between animal models of pulmonary disease. Automation provides many advantages including significantly improved speed and minimized operator interaction and biasing. The results are validated by comparison with previously published rat pulmonary arterial micro-CT data analysis techniques, in which vessels were manually mapped and measured using intense operator intervention.
Atlanta and Other Olympic Losers

Cities launch major campaigns to convince the International Olympic Committee to grace them with a staging of the Summer or Winter Games, and they spare no expense in readying their cities for the ...
METABOLIC ALKALOSIS WITH DIARRHEA AND CHLORIDE-FREE URINE.

The virtual absence of chloride in the urine and a concentration of chloride infeces which exceeds that of sodium are unique features of congenital alkalosis with diarrhea. Five patients with this disorder have been described and the available evidence is interpreted to indicate that the fundamental derangement is excessive loss of chloride in feces. The subject of the present report has deficient intestinal disaccharidase activity, probably secondary to the chronic diarrheal disorder. In all probability a number of associated primary or secondary metabolic disorders will be found in children with this condition.