cssi/SciSciGPT-SciSciNet huggingface dataset:
A convenient synthesis of 2′-deoxyribonucleoside 5′-(α-P-borano)triphosphates

Abstract A new class of nucleotides, with one of the two non-bridging oxygens at α-phosphorus replaced by a borane (BH 3 ) group, has shown potential applications in DNA sequencing. We have developed a convenient method for the synthesis of the 2′-deoxy-5′-(α-P-borano)triphosphates of adenosine, guanosine, cytidine, thymidine and uridine ( 6a-e ) that is time and cost effective compared to the previously reported method. The appropriate base/sugar protected nucleoside 1 is phosphitylated with 2-chloro-4 H -1,3,2-benzodioxaphosphorin-4-one to give the corresponding cyclic intermediate, 2-(2′-deoxyribonucleosidyl-5′- O -)-4 H -1,3,2-benzodioxaphosphorin-4-one ( 2 ). The in situ reaction of 2 with pyrophosphate leads to P 2 , P 3 -dioxo- P 1 -(2′-deoxyribonucleosidyl-5′-)cyclotriphosphite ( 3 ). Subsequent reaction of 3 with N , N -diisopropylethylamine-borane complex yields P 1 -borano-(2′-deoxyribonucleosidyl-5′)cyclotriphosphate ( 4 ), which upon hydrolysis under mild conditions gives the base/sugar protected 2′-deoxyribonucleoside-5′-( α - P -borano)triphosphate ( 5 ). Treatment of 5 with ammonia:methanol (2:1 v/v) yields the diastereoisomeric mixture of 2′-deoxyribonucleoside-5′-( α - P -borano)triphosphate ( 6 ). Separation of the two diastereoisomers of 6 is performed by reverse phase HPLC.
Function of Carotenoids in Photosynthetic Bacteria

A RELATION between photosensitivity and the loss of carotenoid pigments has been observed in Rhodopseudomonas 1, Chlorella 2, Chromatium 3, Chlamydomonas 4, Rhodospirillum 5, Corynebacterium 6 and Zea mays 7. Sistrom et al. have suggested that photosensitization in the carotenoidless mutant of Rhodopseudomonas spheroides ‘… is a specific consequence of the replacement of carotenoid pigments with a colourless polyene.’ and that ‘… the primary function of carotenoid pigments in phototrophs is to act as chemical buffers against photo-oxidation of other cell constituents by chlorophyll, thus conferring a high degree of immunity to endogenous photosensitization.’8 The carotenoid may carry out this buffering function by acting as a preferentially photo-oxidizable substrate. The effectiveness of such a photochemical buffering system would depend on the existence of an enzymatic mechanism which could reduce the photo-oxidized carotenoid. Inhibition of this enzymatic reduction should result in photosensitization. Accordingly, the effect of low temperature on the photosensitivity of wild type R. spheroides (2.4.1) and Rhodospirillum rubrum was investigated.
Short-range order and frustration in omphacite: Comparison of three CVM approximations

We compare three cluster variation method (CVM) models for order-disorder in omphacite (Al0.5Mg0.5)[Na0.5Ca0.5]Si2O6: the generalized point approximation (GPA), generalized pair approximation (GPaA) and an approximation that is based on two eight-body clusters (2X8A). The same Hamiltonian (set of pairwise interactions) is used for all three approximations. Pair probabilities predicted by the GPA obey the geometric constraints of the crysal structure (the frustration constraint), but the exclusion of short-range order (SRO) leads to overestimates of the configurational internal energy (〈E〉), and the critical temperature for cation order-disorder (Tc). The GPaA violates the frustration constraint, and it therefore fails to predict a P21/n → C2/c order-disorder transition and yields values for 〈E〉 and SRO that are inconsistent with the omphacite crystal structure. The 2X8A predicts SRO that is consistent with the frustration constraint, and it yields improved (lower) estimates of 〈E〉 and Tc relative to the GPA: 〈E〉2X8A<〈E〉GPA, and Tc(2X8A)≈0.741 Tc(GPA).
Automatically Reducing Repetitive Synchronization with a Just-in-Time Compiler for Java

We describe an automatic technique to remove repetitive synchronization in Java/spl trade/ programs by removing selected MONITORENTER/EXIT operations. Once these operations are removed, parts of a method that were not originally locked become protected by a lock. If it is unsafe to synchronize the code between the original locked regions, however, the code is not transformed. Scalability is also protected by not allowing a lock to be held for a significantly longer time than it would be held in the original program code. Our base algorithm improved the throughput of the industry-standard SPECjbb2000 benchmark by 2% to 5% for three different platforms. We also describe an extension to our algorithm to better handle virtual calls, which are prevalent in Java code, and this extension provides up to a further 5% improvement. Our computationally efficient algorithm was implemented and evaluated in a production Just-In-Time (JIT) compiler.
Effects of drought and CO2 enrichment on competition between two old-field perennials.

summary We studied the effects of drought stress and CO2 enrichment on the competition between Aster pilosus Willd. (aster, C3) and Andropogon virginicus L. (broomsedge, C4) under two CO2 concentrations (350 and 650 μl l−1 CO2) and two water treatments (well-watered and water-limited). Although broomsedge is the more drought-tolerant species, this did not increase its competitive ability against aster under drought conditions. With CO2 enrichment, aster was a stronger competitor than broomsedge and comprised 75% of above-ground pot biomass in both water treatments. CO2 enrichment also increased aster survival when competing with broomsedge under extreme drought conditions. Although drought stress and CO2 enrichment interacted to affect the two species in different ways, there was no interaction of drought stress and competition; aster was a stronger competitor than broomsedge under CO2 enrichment in both well-watered and water-limited conditions. With future increases in the atmospheric CO2 concentration, aster may delay broomsedge dominance in old-field communities.
Marine Biocatalysts: Enzymatic Features and Applications

In several recent reports related to biocatalysis the enormous pool of biodiversity found in marine ecosystems is considered a profitable natural reservoir for acquiring an inventory of useful biocatalysts. These enzymes are characterized by well-known habitat-related features such as salt tolerance, hyperthermostability, barophilicity and cold adaptivity. In addition, their novel chemical and stereochemical characteristics increase the interest of biocatalysis practitioners both in academia and research industry. In this review, starting from the analysis of these featuring habitat-related properties, important examples of marine enzymes in biocatalysis will be reported. Completion of this report is devoted to the analysis of novel chemical and stereochemical biodiversity offered by marine biocatalysts with particular emphasis on current or potential applications of these enzymes in chemical and pharmaceutical fields. The analysis of literature cited here and the many published patent applications concerning the use of marine enzymes supports the view that these biocatalysts are just waiting to be discovered, reflecting the importance of the marine environment. The potential of this habitat should be thoroughly explored and possibly the way to access useful biocatalysts should avoid destructive large-scale collections of marine biomass for enzyme production. These two aspects are day by day increasing in interest and a future increase in the use of marine enzymes in biocatalysis should be expected.
Configurational probabilities for monomers, dimers and trimers in fluids

A new analytical approach is proposed to model aggregation of molecules with isotropic, nearest-neighbor, attractive interactions. By treating the clustering process as a chain reaction, equations with the exact high temperature limit are derived by evaluating the occupation probabilities of nearest neighbors based on the Ono-Kondo approach for a hexagonal lattice to calculate the configurational probabilities of i-mers (i = 1, 2, 3). Equilibrium constants for dimers and trimers are calculated based on the configurational probability data. The proposed model agrees well with Monte Carlo simulations at medium and high temperatures. At low temperatures, the model can be improved by considering the full set of site densities in the first shell of a central trimer. Approximate analytical solutions derived from exact calculations of the grand partition function for monomer adsorption on a 4 × N hexagonal lattice with cylindrical boundary conditions also are presented.
Receptor systems involved in norepinephrine release in heart failure : focus on dopaminergic systems

The sympathetic nervous system is under extraordinarily complex modulation, involving numerous presynaptic and postsynpatic control mechanisms. These highly conserved and very redundant control mechanisms allow for the sympathetic nervous system to adapt quickly and precisely to altered environmental stress or conditions. Heart failure (HF) is characterized by excessive sympathetic activity, with both enhanced "spillover" and reduced clearance of norepinephrine (NE). The normal inhibitor control mechanisms appear faulty, with unleashed sympathetic activity likely contributing to the pathophysiology of the clinical syndrome and being associated with excessive mortality. Attempts to attenuate pharmacologically the release or "spillover" of NE from sympathetic neurons in HF has remained an attractive therapeutic strategy, and various alpha 2 adrenergic agonists and dopaminergic agents have been studied in several small clinical trials. Agents designed to activate both presynaptic (DA2) and postsynaptic or vascular (DA1) receptors have demonstrated promise. Ibopamine, a prodrug that is converted metabolically to epinine, a DA1 > DA2 agonist, has potential for selective vasodilation of mesenteric, renal, cerebral, and coronary vascular beds while reducing NE release and aldosterone activity. Preliminary clinical trials with ibopamine are encouraging, but placebo-controlled multicenter studies will be necessary to establish its role in the treatment of HF.
Attenuation of 10 MeV electron beam energy to achieve low doses does not affect Salmonella spp. inactivation kinetics

Abstract The effect of attenuating the energy of a 10 MeV electron beam on Salmonella inactivation kinetics was investigated. No statistically significant differences were observed between the D 10 values of either Salmonella 4,[5],12:i:- or a Salmonella cocktail ( S . 4,[5],12:i:-, Salmonella Heidelberg, Salmonella Newport, Salmonella Typhimurium, Salmonella ) when irradiated with either a non-attenuated 10 MeV eBeam or an attenuated 10 MeV eBeam (~2.9±0.22 MeV). The results show that attenuating the energy of a 10 MeV eBeam to achieve low doses does not affect the inactivation kinetics of Salmonella spp. when compared to direct 10 MeV eBeam irradiation.
Abuse and neglect in psychiatrically hospitalized multihandicapped children

Medical charts of 150 consecutive admissions of multihandicapped children to a psychiatric hospital were examined to determine the extent and characteristics of abuse and neglect. Results indicated that 39% of the sample experienced or had a history that warranted suspicion of past and/or current maltreatment. Physical abuse was the most frequent type of maltreatment, followed by neglect and sexual abuse. Maltreated multihandicapped patients admitted to the psychiatric unit were less likely to receive diagnoses of organic brain syndrome or profound mental retardation than nonmaltreated multihandicapped counterparts on the same unit. Moreover, data indicated that less severely impaired patients were more likely to be maltreated than were the more severely impaired. Particularly striking was the severity of maltreatment in this multihandicapped sample and the relatively high percentage (40%) of sexually abused patients who were assaulted by multiple perpetrators.
Measuring the outcomes and impacts of innovation interventions: assessing the role of additionality

Additionality is a main technique in the evaluation of innovation, yet there is debate on the theoretical basis, and appropriate application of the technique, when measuring value for money and economic impact. This paper assesses additionality in measuring the outcomes and impacts of innovation interventions, describing the development and use of additionality, and presenting an organising framework. A review is made of the use of the method across a number of micro-evaluations of regional policy interventions, and a series of innovation-related programmes within a regional development agency. The review confirms limitations of the technique in theory and current practice, but using a standardised approach, demonstrates the potential role of the technique in identifying the relative benefits of R&D interventions, and as such, providing a valid contribution to the evidence base informing innovation policy and practice.
Effects of visceral sympathectomy on 2-deoxy-d-glucose induced eating.

Abstract The glucose anti-metabolite 2-deoxy-d-glucose (2DG) when infused through the hepatic-portal circulation caused greater food intake with shorter latency to eat than jugular vein infusion when this comparison was made in intact female rabbits. In visceral sympathectomized rabbits hepatic-portal-2DG infusions had little immediate effect on feeding whereas jugular vein infusion of 2DG had a greater effect than in intact rabbits. The results of hepatic-portal 2DG infusions support the existence of hepatic glucoreceptors and their innervation by afferents passing through the visceral sympathetic ganglia. The fact that visceral sympathetomy enhanced food intake after jugular 2DG, which probably differentially activates central glucoreceptors, suggests that CNS glucoreceptors may play an important role in feeding. However, when CNS glucoreceptors are activated by extremes of glucoprivation their effect on feeding may be masked by central sympathetic activation causing inhibition of feeding.
Multitechnique surface spectroscopic studies of plasma-modified polymers II: H2O/Ar plasma-modified polymethylmethacrylate/polymethacrylic acid copolymers

Results from the x-ray photoelectron spectroscopy (XPS or ESCA), ion scattering spectroscopy (ISS or LEIS), and Fourier transform infrared spectrometry (FTIR) analyses are presented for unmodified and modified poly (methylmethacrylate)/poly (methacrylic acid) (PMMA/PMAA) copolymer films. Analyses of the unmodified PMMA/PMAA copolymer series, via ESCA, ISS, and FTIR, established the surface composition and functionality of the PMMA/PMAA copolymers before the H2O/Ar rf-plasma treatment was employed. The ESCA, ISS, and FTIR analysis of these modified PMMA/PMAA copolymers show that surface modification over a limited depth (50–200 A) has occurred. The composition, bonding, and functionality changes of the surfaces are discussed. A two-step modification mechanism (surface reduction of the PMMA/PMAA copolymer followed by H2O adsorption) is proposed to interpret the spectroscopic results.
Verbalization and optional reversal shifts among kindergarten children

Summary Previous research has found that the proportion of children who make optional reversal shifts increases with age. One explanation offered for this result is that as children get older they are more likely to respond to discrimination-learning situations by making covert mediating responses. These responses are of such a nature that they facilitate transfer from S+ to S−. In human Ss it is further assumed that these covert mediators are themselves verbal or are activated by verbal representational responses. The present research was designed to determine whether instructing kindergarten children overtly to label S+ and S− would have the effect assigned to the hypothetical covert response. Two experiments were performed in which children were presented with an initial discrimination involving a relevant and irrelevant dimension. After criterion was attained, a second discrimination was presented in which both dimensions were present and relevant and the reinforcement pattern was changed. This discrimination was called the optional shift because S had the option of reaching criterion on the basis of a reversal shift, an extradimensional shift, or a nonselective (inconsistent) shift. A test series which followed the attainment of criterion on the optional shift provided the means of inferring the basis of the optional shift. In each of the experiments one group of children was instructed to precede their choices during the initial discrimination with a sentence that labelled S+ and S− (V Group). Another group was run on the same discrimination but were given no instructions about verbalization (C Group). The major finding was that the V Group had significantly more optional reversers in both experiments. It was concluded that among kindergarten children overt verbal representation has a function similar to that assigned to the hypothetical covert mediating response. A three-stage analysis of the development of the mediational chain was proposed.
Cisplatin induced cell killing and chromosomal aberrations in CHO cells: treated during G1 or S phase.

Abstract Variation in sensitivity to cisplatin during the cell cycle was studied synchronous cells treated during G1 or late S phase. The cells were assayed for cell killing, cell-cycle delay, and chromosomal aberrations after they were treated with cisplatin (1–12 μg/ml) for 1 h at 37°C. They were either plated for colony survival, or colcemid was added from 12 to 40 h after plating followed by fixation 4 h later for analysis of chromosal aberrations after the cells completed 1 or 2 cycles (i.e. first or second mitosis). Cells treated with 6 μg/ml exhibited about a 10-h delay during the first cycle after treatment during G1 compared with about 3 h during the first cycle and 6 h during the second cycle after treatment during late S. In both cases, cells entering metaphase exhibited predominantly chromatid-type breaks and exchanges. For both cell killing and chromosomal aberrations, the cells in G1 were 1.5–1.6 times more sensitive than those treated in late S, with 1 aberration per cell corresponding to about 37% survival. However, the exchanges and breaks were observed primarily in the first mitosis when cells were treated in G1 compared with the second mitosis when cells were treated in late S. These results suggest that DNA replication opposite cisplatin cross-links in the DNA results in lethal chromosomal aberrations.
Short- and Long-Run Performance of Initial Public Offerings in Postapartheid South Africa

This paper examines the impact of liberalization on initial public offering (IPO) performance in postapartheid South Africa. Results indicate a significant reduction in IPO underpricing in the postapartheid period relative to the level reported for IPO offerings in the apartheid period. Significant long-term underpricing for periods of up to two years following the IPO is noted. Many IPO offerings in South Africa are delisted and acquired or merged within three to five years of the IPO offering. Subsequently acquired IPOs are found to be more underpriced than are nonacquired IPOs, a result consistent with the use of IPOs as a means of facilitating acquisitions and mergers.
Accurate cell counts in live mouse embryos using optical quadrature and differential interference contrast microscopy

Present imaging techniques used in in vitro fertilization (IVF) clinics are unable to produce accurate cell counts in developing embryos past the eight-cell stage. We have developed a method that has produced accurate cell counts in live mouse embryos ranging from 13-25 cells by combining Differential Interference Contrast (DIC) and Optical Quadrature Microscopy. Optical Quadrature Microscopy is an interferometric imaging modality that measures the amplitude and phase of the signal beam that travels through the embryo. The phase is transformed into an image of optical path length difference, which is used to determine the maximum optical path length deviation of a single cell. DIC microscopy gives distinct cell boundaries for cells within the focal plane when other cells do not lie in the path to the objective. Fitting an ellipse to the boundary of a single cell in the DIC image and combining it with the maximum optical path length deviation of a single cell creates an ellipsoidal model cell of optical path length deviation. Subtracting the model cell from the Optical Quadrature image will either show the optical path length deviation of the culture medium or reveal another cell underneath. Once all the boundaries are used in the DIC image, the subtracted Optical Quadrature image is analyzed to determine the cell boundaries of the remaining cells. The final cell count is produced when no more cells can be subtracted. We have produced exact cell counts on 5 samples, which have been validated by Epi-Fluorescence images of Hoechst stained nuclei.
Inhibitory effect of electroacupuncture (EA) on the pressor response induced by exercise stress

We examined the effect of EA on the exercise stress-induced pressor response in healthy adult subjects of both sexes. Each subject was subjected to a bicycle exercise test using a ramp protocol once/week for three or four weeks. Subjects were asked to perform the following tests in random order: 1) a baseline exercise test without EA and 2) exercise after acupuncture at P 5-6, LI 4-L 7 and/or G 37-39 acupoints. Brachial systolic (SBP), diastolic (DBP), and mean blood pressures (MBP), heart rate (HR) and the rate-pressure product (RPP, systolic BP x HR/100) were measured every three min, while a 12 lead ECG was monitored continuously. We observed increases in MBP, SBP, HR and RPP in all 17 subjects during exercise. In 12 of the 17 subjects (71 %), EA for 30 min before exercise, either at Jianshi-Neiguan acupoints (P 5-6) or Hegu-Lique acupoints (LI 4-L 7), led to an increase in maximal workload, and reduced peak SBP, MBP and RPP responses to exercise; EA did not alter DBP or HR responses in these subjects. EA at control acupoints (Guangming-Xuanzhong acupoints, G 37-39) in five subjects did not alter the hemodynamic responses. Seven additional subjects were enrolled to study the effect of EA during a bicycle exercise test using a constant workload. The results were similar, in five of the seven subjects SBP, MBP and RPP after exercise were attenuated significantly by EA at P 5-6. We conclude that EA at specific acupoints improves exercise capacity and reduces the hemodynamic responses in approximately 70% of normal subjects.
Stabilizing slow light delay in stimulated Brillouin scattering using a Faraday rotator mirror

The delay of the Stokes beam in stimulated Brillouin scattering (SBS) is sensitive to the polarization alignment between the pump and the Stokes. Typically, waveguides exhibit a birefringence that causes beams launched from opposite ends to have fluctuating and suboptimal alignment. We demonstrate in an optical fiber that using a Faraday rotator mirror not only overcomes this problem, but also enhances SBS slow light delay.
A new stochastic approach to transient heat conduction modeling with uncertainty

We present a generalized polynomial chaos algorithm for the solution of transient heat conduction subject to uncertain inputs, i.e. random heat conductivity and capacity. The stochastic input and solution are represented spectrally by the orthogonal polynomial functionals from the Askey scheme, as a generalization of the original polynomial chaos idea of Wiener [Am. J. Math. 60 (1938) 897]. A Galerkin projection in random space is applied to derive the equations in the weak form. The resulting set of deterministic equations is subsequently discretized by the spectral/hp element method in physical space and integrated in time. Numerical examples are given and the convergence of the chaos expansion is demonstrated for a model problem.
Development of lactic acid-receptor sensitivity and host-seeking behaviour in newly emerged female Aedes aegypti mosquitoes

Abstract The temporal patterns for the development of sensitivity in the lactic acid-excited neurones of the antennal grooved-peg sensilla and for the initiation of host-seeking behaviour by newly emerged virgin female Aedes aegypti mosquitoes were determined and compared. A 1:1 correlation between the presence of a high sensitivity to the host attractant, lactic acid, in the lactic acid-excited neurones and the presence of host-seeking behaviour was observed. This finding supports the notion that changes in the activity of the peripheral sensory system are sufficient, although perhaps not the only means, to control host-seeking behaviour of female mosquitoes.
Fine structural differences in "fast" and "slow" muscle fibers of the crab.

The muscle fibers in the accessory flexor muscle of the crab were examined with the electron microscope. The limiting membrane of the muscle fiber invaginates at many points to form an internal extrafibrillar membranous system between the muscle fibrils. Two types of muscle fiber were found. In one, the fibrils are well separated from each other by an extensive membranous system, the sarcomere lengths are short, and the filaments in the A band are thick. This muscle fiber is the same as the fast fiber previously found physiologically. The other type of muscle fiber has large fibrils poorly separated by a relatively scant system of internal membranes. It has relatively long sarcomeres and comparatively thin filaments in the A band. This type of fiber is the same as the slow fibers described physiologically. Fibers intermediate in type are also found. Nerve terminals with typical synaptic vesicles occur and appear similar on both types of muscle fiber under the electron microscope. Membrane thickenings of nerve ending and muscle fiber also occur at the terminals on both types of muscle fiber. The nerve terminals on the fast fiber are much more easily found and hence more numerous than on the slow fiber. A comparison is made between the invertebrate and vertebrate fast and slow fibers, and some physiological implications of these findings are discussed.
Cell-Restricted Immortalization by Human Papillomavirus Correlates with Telomerase Activation and Engagement of the hTERT Promoter by Myc

The high-risk human papillomaviruses (HPVs) are the causative agents of nearly all cervical cancers and are etiologically linked to additional human cancers, including those of anal, oral, and laryngeal origin. The main transforming genes of the high-risk HPVs are E6 and E7. E6, in addition to its role in p53 degradation, induces hTERT mRNA transcription in genital keratinocytes via interactions with Myc protein, thereby increasing cellular telomerase activity. While the HPV type 16 E6 and E7 genes efficiently immortalize human keratinocytes, they appear to only prolong the life span of human fibroblasts. To examine the molecular basis for this cell-type dependency, we examined the correlation between the ability of E6 to transactivate endogenous and exogenous hTERT promoters and to immortalize genital keratinocytes and fibroblasts. Confirming earlier studies, the E6 and E7 genes were incapable of immortalizing human fibroblasts but did delay senescence. Despite the lack of immortalization, E6 was functional in the fibroblasts, mediating p53 degradation and strongly transactivating an exogenous hTERT promoter. However, E6 failed to transactivate the endogenous hTERT promoter. Coordinately with this failure, we observed that Myc protein was not associated with the endogenous hTERT promoter, most likely due to the extremely low level of Myc expression in these cells and/or to differences in chromatin structure, in contrast with hTERT promoters that we found to be activated by E6 (i.e., the endogenous hTERT promoter in primary keratinoctyes and the exogenous hTERT core promoter in fibroblasts), where Myc is associated with the promoter in either a quiescent or an E6-induced state. These findings are consistent with those of our previous studies on mutagenesis and the knockdown of small interfering RNA, which demonstrated a requirement for Myc in the induction of the hTERT promoter by E6 and suggested that occupancy of the promoter by Myc determines the responsiveness of E6 and the downstream induction of telomerase and cell immortalization.
Improve precategorized collection retrieval by using supervised term weighting schemes

The emergence of the World Wide Web has led to an increased interest in methods for searching for information. A key characteristic of many online document collections is that the documents have pre-defined category information, such as the variety of scientific articles accessible via digital libraries (e.g. ACM, IEEE, etc.), medical articles, news-wires and various directories (e.g. Yahoo, OpenDirectory Project, etc.). However, most previous information retrieval systems have not taken the pre-existing category information into account. In this paper, we present weight adjustment schemes based upon the category information in the vector-space model, which are able to select the most content-specific and discriminating features. Our experimental results on TREC data sets show that the pre-existing category information does provide additional beneficial information to improve retrieval. The proposed weight adjustment schemes perform better than the vector-space model with the inverse document frequency (IDF) weighting scheme when queries are less specific. The proposed weighting schemes can also benefit retrieval when clusters are used as an approximations to categories.
MORPHOLOGICAL VARIATION OF ACHNANTHES HAUCKIANA (BACILLARIOPYCEAE) IN THE RIELD1

SUMMARY Samples of 2 populations of the diatom, Achnanthes hauckiana Grun., collected from Sippewissett Marsh, Massachusetts, were measured. Regression analyses of the measurements were calculated. The length/width ratio of both samples decreased almost linearly with decreasing length. The length/width ratio of the rostrate ends also decreased almost linearly with decreasing length. The number of striae per 10 μm showed a slight tendency to increase with decreasing length. Some of the specimens collected, which fit the descriptions of A. hauckiana var. elliptica or ver. rostrata, appear to be morphological variants of the nominate variety. The change in shape with size fits Geitler's rule of proportionally greater decrease in the apical axis than the decrease in the transapical axis. The regression lines of change in shape with size might be used as taxonomic characteristics and contain more information than the usual descriptions of limits of size and shape of a species.
Seasonal and diurnal variations of 13 C 18 O 16 O in air: Initial observations from Pasadena, CA

The budget of atmospheric CO_2 is widely studied using records of temporal and spatial variations of concentrations, δ^(13)C and δ^(18)O values. However, the number and diversity of sources and sinks prevents these alone from fully constraining the budget. Molecules containing two rare isotopes can serve as additional tracers and potentially provide additional, independent, constraints. We present data documenting seasonal and diurnal variations of CO_2 having a mass of 47 u (mostly ^(13)C^(18)^O(16)O) in air from Pasadena, CA. We report these data using the ‘mass 47 anomaly’ (Δ_(47)), which is defined as the deviation of R^(47)(=[47]/[44]) from that expected for a random distribution of isotopologues. Between February 2004 and December 2005, Δ_(47) showed a seasonal pattern that differed significantly from that expected based on thermodynamic equilibrium. During the year 2004 Δ_(47) was 0.76‰ in winter, increased to 0.87‰ in summer and gradually decreased through the autumn to 0.81‰ at the end of the year. Δ_(47) then increased again through the winter and spring of 2005 to 0.97‰ in summer followed by a decrease to 0.88‰ at the end of 2005. The seasonal variations cannot be accounted for by variations in the relative contribution of local fossil fuel sources. Diurnal variations were the combined effect of both fuel combustion and respiration having Δ_(47) values of 0.41‰ and ca. 0.77‰, respectively. The seasonal cycle may be interpreted as a competition between low Δ_(47) values in respiration and higher Δ_(47) values resulting from CO_2-water exchange in photosynthesis.
Educating Geographers with GIS Skills for the Real World: Some Feedback from Geography Graduates at Southwest Texas State University

Abstract Results of a survey to find out whether the GIS program in the Department of Geography at Southwest Texas Stare University (SWT) has served its graduates well are presented. In recent years, a considerable amount of effort has been given to the development of strategies for expanding the existing horizon of GIS education, integrating existing programs, and improving the ways in which GIS education is delivered. This study takes a different approach and seeks to get input from geography graduates who have secured a job in the real world for improving a university GIS program. Based on 26 responses to the survey, employment categories of SWT geography graduates are examined first. Then, geography courses that are considered most helpful in career development by the survey participants are identified. Third, useful GIS courses and essential skills required by the marketplace in the real world as suggested by the survey participants are discussed. It is clear from the results of the survey that the g...
New Brain Lymphatic Vessels Drain Old Concepts.

The brain has traditionally been considered an immune privileged organ, in part due to the lack of evidence for lymphatic vasculature (Galea et al., 2007). Two centuries ago, the existence of lymphatic vessels on the surface of the human brain was proposed but it has since been widely dismissed (Lukic et al., 2003). Therefore, while T cells leave all other organs via the lymphatic system to reach nearby lymph nodes, the prevailing view has been that infiltrated T cells exit the brain via venous blood circulation, circumventing the lymph nodes (Ransohoff and Engelhardt, 2012). The recent evidence for the existence of a lymphatic vascular system in the brain's meninges provided independently by two labs, first by the Kipnis lab (Louveau et al., 2015) and then by the Alitalo lab (Aspelund et al., 2015), challenges this view and raises the intriguing possibility of an alternative gateway for T cells to egress the brain.
Active spectral clustering via iterative uncertainty reduction

Spectral clustering is a widely used method for organizing data that only relies on pairwise similarity measurements. This makes its application to non-vectorial data straight-forward in principle, as long as all pairwise similarities are available. However, in recent years, numerous examples have emerged in which the cost of assessing similarities is substantial or prohibitive. We propose an active learning algorithm for spectral clustering that incrementally measures only those similarities that are most likely to remove uncertainty in an intermediate clustering solution. In many applications, similarities are not only costly to compute, but also noisy. We extend our algorithm to maintain running estimates of the true similarities, as well as estimates of their accuracy. Using this information, the algorithm updates only those estimates which are relatively inaccurate and whose update would most likely remove clustering uncertainty. We compare our methods on several datasets, including a realistic example where similarities are expensive and noisy. The results show a significant improvement in performance compared to the alternatives.
New results on paraunitary filter banks over finite fields

In the complex field, unitary and paraunitary (PU) matrices have found many applications in signal processing. There has recently been interest in extending these ideas to the case of finite fields. In this paper, we will study the theory of PU filter banks in GF(q) with q prime. Various properties of unitary and PU matrices in finite fields will be studied. In particular, a number of factorization theorems will be given. We will show that: (i) All unitary matrices in GF(q) are factorizable in terms of Householder-like matrices and a permutation matrix. (ii) The class of first-order PU matrices, the lapped orthogonal transform in finite fields, can always be expressed as a product of degree-one or degree-two building blocks. If q>2, we do not need degree-two building blocks. While many properties of PU matrices in finite fields are similar to those of PU matrices in the complex field, there are a number of differences. For example, unlike the conventional PU systems, in finite fields there are PU systems that are unfactorizable in terms of smaller building blocks.
Selection for Silage Yield and Composition Did Not Affect Genomic Diversity Within the Wisconsin Quality Synthetic Maize Population

Maize silage is forage of high quality and yield, and represents the second most important use of maize in the United States. The Wisconsin Quality Synthetic (WQS) maize population has undergone five cycles of recurrent selection for silage yield and composition, resulting in a genetically improved population. The application of high-density molecular markers allows breeders and geneticists to identify important loci through association analysis and selection mapping, as well as to monitor changes in the distribution of genetic diversity across the genome. The objectives of this study were to identify loci controlling variation for maize silage traits through association analysis and the assessment of selection signatures and to describe changes in the genomic distribution of gene diversity through selection and genetic drift in the WQS recurrent selection program. We failed to find any significant marker-trait associations using the historical phenotypic data from WQS breeding trials combined with 17,719 high-quality, informative single nucleotide polymorphisms. Likewise, no strong genomic signatures were left by selection on silage yield and quality in the WQS despite genetic gain for these traits. These results could be due to the genetic complexity underlying these traits, or the role of selection on standing genetic variation. Variation in loss of diversity through drift was observed across the genome. Some large regions experienced much greater loss in diversity than what is expected, suggesting limited recombination combined with small populations in recurrent selection programs could easily lead to fixation of large swaths of the genome.
A rapid supercritical extraction process for the production of silica aerogels

Silica aerogels are a special class of porous materials in which both the pore size and interconnected particle size have nanometer dimensions. This structure imparts unique optical, thermal, acoustic, and electrical properties to these materials. Transmission electron microscopy and small angle x-ray scattering show that this nanostructure is sensitive to variations in processing conditions that influence crosslinking chemistry and growth processes prior to gelation. Recently, Lawrence Livermore National Laboratory (LLNL) has demonstrated that a Rapid Supercritical Extraction (RSCE) process can be used to prepare near-net shape silica aerogels in hours rather than days. Preliminary data from RSCE silica aerogels show that they have improved mechanical properties and slightly lower surface areas than their conventionally dried counterparts, while not compromising their optical and thermal performance.
New algorithms for the placement and routing of macro cells

Novel algorithms are described for timing driven placement and routing of rectilinearly shaped macro cells. Algorithms are also presented for the implementation of simulated annealing, based on a theoretically derived statistical annealing schedule. A negative feedback scheme is described that optimizes the relative weighting between the primary objective term and the penalty function terms in the cost function. A placement refinement method has been developed for rectilinear cells which spaces the cells at a density which avoids the need for post-routing compaction. In addition, a detailed routing method has been developed which avoids the classically difficult problem of defining channels for detailed routing. The result for the ami33 benchmark circuit is better than the previously published results. >
“Business Ethics Everywhere” An Experiential Exercise to Develop Students’ Ability to Identify and Respond to Ethical Issues in Business

This article introduces an experiential exercise that enhances students’ ability to identify ethical issues and to respond to them in ways that consider the relationship between organizational factors and ethical action. Students identify a required number of ethical incidents in their workplaces during a specified period. Students submit a written description for each incident, drawing from moral philosophical frameworks and/or other ethical concepts to label the issue as one that either exemplifies a “best practice” or “raises concern.” For “best practice” examples, students consider the implications of the practice on the organization and its stakeholders and whether and how the practice could be improved. For examples that “raise concern,” students explain what the ethically appropriate action would be, indicate whether they would take that action, report any reservations they have about taking that right action, and consider how to behave ethically in a way that would bring about desired outcomes wit...
Adaptive insertion policies for managing shared caches

Chip Multiprocessors (CMPs) allow different applications to concurrently execute on a single chip. When applications with differing demands for memory compete for a shared cache, the conventional LRU replacement policy can significantly degrade cache performance when the aggregate working set size is greater than the shared cache. In such cases, shared cache performance can be significantly improved by preserving the entire working set of applications that can co-exist in the cache and preserving some portion of the working set of the remaining applications. This paper investigates the use of adaptive insertion policies to manage shared caches. We show that directly extending the recently proposed dynamic insertion policy (DIP) is inadequate for shared caches since DIP is unaware of the characteristics of individual applications. We propose Thread-Aware Dynamic Insertion Policy (TADIP) that can take into account the memory requirements of each of the concurrently executing applications. Our evaluation with multi-programmed workloads for 2-core, 4-core, 8-core, and 16-core CMPs show that a TADIP-managed shared cache improves overall throughput by as much as 94%, 64%, 26%, and 16% respectively (on average 14%, 18%, 15%, and 17%) over the baseline LRU policy. The performance benefit of TADIP is 2.6x compared to DIP and 1.3x compared to the recently proposed Utility-based Cache Partitioning (UCP) scheme. We also show that a TADIP-managed shared cache provides performance benefits similar to doubling the size of an LRU-managed cache. Furthermore, TADIP requires a total storage overhead of less than two bytes per core, does not require changes to the existing cache structure, and performs similar to LRU for LRU friendly workloads.
Synthesis of robust controllers and filters

This paper outlines a general framework for analysis and synthesis of linear control systems and reports on a new solution to a very general L?/H? optimal control problem.
THE EFFECT OF LEVEL OF HETEROZYGOSITY ON THE PERFORMANCE OF HYBRIDS BETWEEN ISOGENIC LINES OF BARLEY

Sixteen "isogenic" lines of Atlas 46 barley differing in one to four short chromosome segments, and 16 heterozygotes obtained by crossing these lines to male-sterile Atlas, were used to study the effect of level of heterozygosity on performance. In field tests conducted in four environments (two planting dates in two years) significant differences were found among the homozygous isogenic lines for the traits seed yield, kernel weight, tiller number, plant height, and heading time; thus each of the marked chromosome segments carries genes which, when homozygous, affect these quantitative characters. It was also found that heterozygotes produced more and heavier kernels and were taller and earlier than homozygotes but there was no clear indication that the degree of heterosis increased as the number of heterozygous segments increased from one to five. Degree of heterosis was, however, strongly affected by the environment, by allelic state at each segment (especially the segment marked by the two-row, six-row spike locus), and also by genotype for other marked segments. These results indicate that heterosis in barley has a more complex structure than can be adequately represented by simple models, such as the multiplicative model in which fitnesses are the product of fitnesses at individual loci, or threshold models in which optimum fitness is approached asymptotically as the number of heterozygous loci increases.
Concentration and binary separation of micro particles for droplet-based digital microfluidics

This paper describes a concept of concentration and binary separation of particles and its experimental confirmations for digital microfluidics where droplets are driven by the mechanism of electrowetting-on-dielectric (EWOD). As a fundamental separation unit, a binary separation scheme is developed, separating two different types of particles in one droplet into two droplets, one type each. The separation scheme consists of three distinctive steps, each with their own challenges: (1) isolate two different types of particles by electrophoresis into two regions inside a mother droplet, (2) physically split the mother droplet into two daughter droplets by EWOD actuation so that each type of particle is concentrated in each daughter droplet, and (3) free the daughter droplets from the separation site by EWOD to ready them for follow-up microfluidic operations. By applying a similar procedure to a droplet containing only one type of particle, two daughter droplets of different particle concentrations can be created. Using negatively charged carboxylate modified latex (CML) particles, 83% of the total particles are concentrated in a daughter droplet. Successful binary separation is also demonstrated using negatively charged CML particles and no-charge-treated polystyrene particles. Despite the undesired vortex developed inside the mother droplet, about 70% of the total CML particles are concentrated in one daughter droplet while about 70% of the total polystyrene particles are concentrated in the other daughter droplet.
Interspecific Competition among Natural Enemies and Single Versus Multiple Introductions in Biological Control

One of the most challenging questions in biological control has been whether the single best natural enemy will provide greater suppression of the abundance of an arthropod pest than a combination of natural enemies due to the effects of competition for a shared resource (the pest). From a theoretical perspective, simple predator-prey models clearly indicate that for multiple natural enemies sharing a single pest, only a single natural enemy will persist in the system, the species that can reduce the pest to the lowest equilibrium density. In addition, the biological control record of natural enemy introductions against invasive insect pests suggests that establishment rates are higher for projects with single versus multiple introductions, and that competitive exclusion can result from a sequence of parasitoid introductions against a pest. From natural field populations, however, it is clear that insect herbivores frequently support a diverse assemblage of both parasitoid and predator species suggesting that resource partitioning can mediate the effects of competition. So how important are competitive interactions in the context of biological control? Here, I consider the asymmetries of competition among natural enemies of arthropod pests, the incidence of competitive exclusion, the mechanisms of coexistence and their consequences for the success of biological control, and the need for a more experimental approach to the study of competition among natural enemies.