cssi/SciSciGPT-SciSciNet huggingface dataset:
YfaE, a ferredoxin involved in diferric-tyrosyl radical maintenance in Escherichia coli ribonucleotide reductase.

Ribonucleotide reductases (RNRs) catalyze the conversion of nucleotides to deoxynucleotides in all organisms. The class I RNRs are composed of a 1:1 complex of two homodimeric subunits: α and β. β contains the diferric-tyrosyl radical (Y•) cofactor essential for the reduction process. In vivo, the mechanism of Y• regeneration from the diferric-β2 (met-β2) or apo-β2 is still unclear. Y• regenerations from met-β2 and apo-β2 have been designated the maintenance and biosynthetic pathways, respectively. To understand these two pathways, 181 genomes that contain nrdAnrdB (genes encoding α and β) were examined. In 29% of the cases, an open reading frame annotated 2Fe2S ferredoxin (YfaE in Escherichia coli) is located next to nrdB. Thus, YfaE has been cloned, expressed, resolubilized, reconstituted anaerobically with Fe2+, Fe3+, and S2-, and characterized by Mossbauer, EPR, and visible spectroscopies. Titration of met-β2 with [2Fe2S]1+-YfaE anaerobically results in the formation of an equilibrium mixture of dife...
Focal segmental glomerular sclerosis in kidney allograft recipients: an evidence-based approach

Abstract Focal segmental glomerular sclerosis (FSGS) causes kidney failure in 2.5% of all end-stage kidney disease patients. FSGS recurs in 20% to 30% of kidney allografts. In a third of kidney recipients with recurrent FSGS, graft loss is attributed to recurrent disease. Complicating the understanding of recurrent FSGS are the facts that (a) many patients with end-stage kidney disease do not undergo a kidney biopsy before transplant and (b) "de novo" FSGS is not uncommon after transplant, occurring in up to 30% of allografts. This review aims to clarify the definitions of recurrent FSGS and to identify risk factors for treatable recurrent FSGS. The pathophysiology of FSGS and therapeutic strategies from clinical trials are discussed.
Diffraction of EM waves by a dielectric/ferrite half-plane and related configurations

Uniform asymptotic high-frequency ray solutions are developed for the problems of diffraction of electromagnetic plane, cylindrical, and surface waves normally incident on the edge of an isotropic, homogeneous dielectric/ferrite half-plane. The boundary conditions developed, which are referred to as the generalized impedance boundary conditions (GIBC), yield solutions that recover the exact geometrical constants of the surface wave fields in these problems. In the limiting case of small thickness, the solutions recover the solutions based on the boundary conditions given by L.A. Weinstein (1969). Furthermore, the relatively simple ray solutions developed are shown to be very accurate by comparing them with those obtained by an independent approach based on the moment method. >
Differential effects of habitat fragmentation on birds and mammals in Valdivian temperate rainforests

Cuatro estudios recientes en vertebrados chilenos subrayan los efectos muy diversos que la fragmentacion del habitat puede tener bajo diversas condiciones. En el sur de Chile, las aves exhibieron relaciones significativas entre la riqueza de especies y el area de habitat ("especies-area"), mientras que tal relacion no se observo en la comunidad de pequenos mamiferos, la cual tiene menos especies. La avifauna de los fragmentos remanentes altamente aislados del Parque Nacional Fray Jorge (IV Region) presentaron relaciones especies-area mas pronunciadas que aquellas de Chile meridional. Lo observado para los pequenos mamiferos fue inesperado aunque puede reflejar un menor potencial de movilidad e inmigracion en este grupo. Ademas, el habitat de la matriz inter-fragmento puede albergar solo a poblaciones grandes de algunas especies, lo que les permitiria capitalizar los recursos que estan disponibles en los fragmentos de bosque. Tal efecto es menos probable para el caso de las aves producto de su mayor movilidad. Aunque la influencia del area de los fragmentos remanentes es mas claro en el caso de las aves en Chile, es probable que los ensambles de mamiferos pequenos sean mas afectados en el corto plazo por la fragmentacion del habitat que las aves, y que una fragmentacion adicional de los bosques templados lluviosos determinara un mayor empobrecimiento de los ensambles de pequenos mamiferos, muchos de los cuales son endemicos en esta region. Estudios adicionales deberian enfatizar el papel de la matriz inter-fragmento, el de los corredores de habitat, y evaluar la sensibilidad relativa de diversas especies al aislamiento de los fragmentos remanentes y a la calidad de la matriz/corredor
Krylov Model Order Reduction of Finite Element Models of Electromagnetic Structures with Frequency-Dependent Material Properties

Krylov subspace-based model order reduction (MOR) of finite element models of electromagnetic structures is not readily applicable when the electromagnetic properties of the materials exhibit arbitrary frequency dependence. This paper presents a methodology for overcoming this hurdle. The proposed Krylov MOR process is demonstrated through its application to the expedient broadband analysis of the impact of skin-effect loss on the transmission properties of a microstrip bandpass filter and the extraction of the propagation characteristics of a microstrip line on a dielectric substrate with frequency-dependent permittivity described by a Debye model.
The inability of squirrel monkeys to localize sound after unilateral ablation of auditory cortex

The ability of squirrel monkeys to localize brief sounds was tested before and after unilateral ablation of auditory cortex. Results indicated that, after unilateral ablation of auditory cortex, monkeys could no longer localize sound accurately in the hemifield opposite to the side of lesion. These data demonstrate that contralaterally-directed functioning of auditory cortex occurs in primates.
Do invertebrate communities in floodplains change predictably along a river's length?

Summary 1. Invertebrate assemblages were described for nine floodplain sites located on a longitudinal gradient of river discharge in the Altamaha River catchment. The Altamaha River and its tributaries constitute one of the few remaining ‘unregulated’ catchments in the southeastern U.S. We predicted that, as the character of lateral flood pulses into backwater swamps changed along the discharge gradient, so would the structure of invertebrate communities. We also examined the relationship between invertebrate assemblages and physicochemical factors (degree of floodplain inundation, pH, conductivity and nutrient concentrations). 2. Cluster analyses of both invertebrate abundance and biomass separated the nine sites into three groups corresponding to their positions in the catchment (upper, mid- and lower reach clusters). Non-metric multidimensional scaling ordinations further corroborated the groupings (with combined axis scores of 92% and 73% for abundance and biomass, respectively) and showed significant correlations with degree of inundation and conductivity (abundance), and conductivity, nitrate and phosphate concentrations (biomass). 3. Floodplains in the upper reaches were dominated by terrestrial taxa, such as earthworms, oribatid mites, collembolans and assorted terrestrial fly larvae, and some rapidly developing aquatics (harpacticoid crustaceans and mosquitoes). In the mid-reach, the dominant taxa were longer lived aquatic organisms such as mayflies and aquatic oligochaetes, although some terrestrial organisms (elaterid beetles and mites) were still common. Invertebrate families dependent on water flow, such as riffle beetles and some mayflies, were common only in mid-reach floodplain sites. Lower reaches were dominated by lentic aquatic taxa such as dytiscid beetles and asellid isopods, which commonly persist in wetlands after they dry. 4. Our study indicates that invertebrate community structure varies predictably among floodplains in the Altamaha catchment, with headwater habitats being dominated by terrestrial and rapidly-developing aquatic invertebrates, mid-reaches characterised by an influx of invertebrates from the river and lower reaches being dominated by wetland taxa with desiccation-resistant stages. This spatial variability should be considered when applying the Flood Pulse Concept.
Biochemical evidence for presence of dopamine β-hydroxylase in rat retina

Abstract Previously, we demonstrated immunocytochemically that certain phenylethanolamine N -methyltransferase neurons in the inner nuclear layer of rat retina contain other catecholamine synthesizing enzymes, including tyrosine hydroxylase and aromatic- l -amino acid decar☐ylase but not dopamine β-hydroxylase (DBH), the norepinephrine biosynthetic enzyme. In the present study by using a sensitive radioenzymatic assay for DBH we demonstrated the presence of DBH enzymatic activity in retinal extracts. Immunocytochemical studies, however, failed to demonstrate DBH-immunoreactive perikarya even in animals pretreated with colchicine, an inhibitor of axonal transport. Probable causes for these discrepant findings are discussed.
Simulations of the thermospheric response to the diffuse aurora using a three‐dimensional high‐resolution model

[1] Recent observations within the substorm recovery phase postmidnight diffuse aurora reveal phenomena that are not well understood. Strong neutral winds are seen within the postmidnight diffuse aurora in measurements from the series of Atmospheric Response in Aurora (ARIA) campaigns, which show a great deal of vertical structure and large vertical shears. The ARIA observations also consistently show a peak in the wind magnitude between around 110 and 120 km, which has not been well explained, with a strong shear below the peak that is sometimes found to be unstable, with a Richardson number < 0.25. A three-dimensional (3-D) high-resolution model developed recently at UCLA has been used to perform simulations to try to understand the poorly explained phenomena found in the ARIA measurements. Model simulations show that large zonal and meridional winds can be produced in the region of the postmidnight diffuse aurora using auroral forcing parameters within the range of observations. A wind maximum is produced in the 110–120 km altitude range, within the same height range as the maxima found in the ARIA observations, using auroral forcing alone. When sufficiently high vertical resolution is used for auroral forcing parameters within the range of observations, the region below the peak may be unstable, with a Richardson number < 0.25. When simulations are performed with auroral forcing based on measurements from the ARIA I campaign, and background winds and tides are introduced from the Coupled Thermosphere–Ionosphere Plasmasphere (CTIP) model [Fuller-Rowell et al., 1987; Bailey et al., 1997], the basic features of the vertical structure of the ARIA I wind measurements are reproduced, although the magnitude of the peak around 115 km altitude is somewhat smaller than that observed. The 115 km peak is likely produced by a combination of auroral and tidal forcing processes. The vertical structure of the winds is sensitive to the phases of the tidal modes. Improvements in the ability of the model to simulate the observations from the ARIA campaign may be due to the use of the 3-D rather than a 2-D high-resolution model.
Effect of slurry viscosity modification on oxide and tungsten CMP

Abstract Chemical mechanical polishing (CMP) of semiconductor substrates is a complex phenomenon that involved chemical and mechanical interactions between substrate material, slurry and pad. The effect of the physical properties of the slurry on the polishing rates is not very well understood. The rheological properties of polishing slurries affect material removal rate and surface quality of the semiconductor wafers. In this work, we have studied the effect of changing viscosity of a commercial colloidal silica-based slurry on removal rate. The pad material selected was a commercial pad. The results show that the effect of viscosity modifiers is very different for oxide and tungsten CMP. This can be related to the fundamental difference in the mechanism of material removal in the two cases. We have discussed these viscosity effects in relation to the mechanisms of materials removal pertaining to both oxide and metal CMP.
Propitious selection in insurance

The theory of propitious selection suggests that there are risk-avoiding personalities who both take physical precautions and buy financial security (insurance). Conversely, there are risk seekers who tend to do neither. Survey evidence is presented that is consistent with the theory. Individuals who obtain motor vehicle liability coverage are less likely than others to drink-and-drive, and are more likely to engage in health-beneficial (risk-avoiding) behaviors. Propitious selection may be a general phenomenon promoting favorable selection in many real world insurance markets.
Unilateral Alpha Subharmonics: A Case Report:

Occipital alpha subharmonics are a normal EEG variant. Unilateral occipital slowing, however, is associated with focal dysfunction of that particular side. We report a 10-year-old girl with the incidental EEG finding of unilateral occipital slowing. MRI of her brain was completely normal and on long-term follow up she remained healthy. Based on her clinical history, normal MRI of brain, and the character of the slow posterior rhythms, we conclude that unilateral slow alpha rhythm can be a normal variant akin to alpha subharmonics.
Maternal serum vascular endothelial growth factor levels in early ectopic and intrauterine pregnancies after in vitro fertilization treatment

Abstract Objective To determine whether serum levels of vascular endothelial growth factor (VEGF) 11 days after a day-3 embryo transfer were predictive of outcome, in women with normal intrauterine pregnancy (IUP), first-trimester miscarriage (SAB), biochemical (BC), and ectopic pregnancy (EP) after IVF therapy. Design Retrospective analysis. Setting University hospital IVF unit. Patient(s) One hundred eight women who underwent IVF therapy and who were subsequently diagnosed with EP, BC, SAB, or a normal IUP (27 in each category). Intervention(s) Serum samples were obtained at 11 days after a day-3 embryo transfer. Main outcome measure(s) Serum concentrations of VEGF, P, and β-hCG. Result(s) Serum concentrations of VEGF were similar in women with BC and EP and higher than in women with normal IUP and SAB (571.8 ± 61.8, 604.4 ± 73.4 vs. 448.9 ± 39.9, 461.8 ± 39.2 pg/mL, respectively). Also, serum β-hCG and P levels were significantly higher in women with a normal IUP and SAB. Using a cutoff concentration of >700 pg/mL for VEGF, an EP could be distinguished from an IUP (normal and SAB), with a positive predictive value of 64% and a negative predictive value of 71%. Conclusion(s) Elevated maternal serum levels of VEGF, as early as 11 days after embryo transfer, are associated with ectopic pregnancies after IVF.
Generalization of morphine and lysergic acid diethylamide (LSD) stimulus properties to narcotic analgesics

The present investigation sought to determine whether the stimulus properties of morphine and lysergic acid diethylamide (LSD) would generalize to several narcotic analgesics which vary in their subjective effects. Morphine and saline served as discriminative stimuli for one group of rats in a 2-lever discrimination task. LSD and saline were discriminative stimuli for a second group. Depression of one lever in an operant chamber resulted in reinforcement following the administration of morphine or LSD and the opposite lever was reinforced after saline. After discriminated responding was stable, stimulus generalization tests with narcotic analgesics and antagonists showed that the stimulus properties of morphine generalized to methadone and meperidine, and partially to pentazocine, all of which produce morphine-like subjective effects in humans. Morphine stimulus properties did not generalize to nalorphine or cyclazocine, which produce dissimilar subjective effects. The stimulus properties of LSD generalized partially to cyclazocine, but not to nalorphine. In humans cyclazocine and nalorphine produce a high incidence of psychotomimetic effects, but the subjective effects of cyclazocine are differentiable from those of LSD.
Reduction of plasma triglycerides in apolipoprotein C-II transgenic mice overexpressing lipoprotein lipase in muscle.

LPL and its specific physiological activator, apolipoprotein C-II (apoC-II), regulate the hydrolysis of triglycerides (TGs) from circulating TG-rich lipoproteins. Previously, we developed a skeletal muscle-specific LPL transgenic mouse that had lower plasma TG levels. ApoC-II transgenic mice develop hypertriglyceridemia attributed to delayed clearance. To investigate whether overexpression of LPL could correct this apoC-II-induced hypertriglyceridemia, mice with overexpression of human apoC-II (CII) were cross-bred with mice with two levels of muscle-specific human LPL overexpression (LPL-L or LPL-H). Plasma TG levels were 319 ± 39 mg/dl in CII mice and 39 ± 5 mg/dl in wild-type mice. Compared with CII mice, apoC-II transgenic mice with the higher level of LPL overexpression (CIILPL-H) had a 50% reduction in plasma TG levels (P = 0.013). Heart LPL activity was reduced by ∼30% in mice with the human apoC-II transgene, which accompanied a more modest 10% decrease in total LPL protein. Overexpression of human LPL in skeletal muscle resulted in dose-dependent reduction of plasma TGs in apoC-II transgenic mice. Along with plasma apoC-II concentrations, heart and skeletal muscle LPL activities were predictors of plasma TGs. These data suggest that mice with the human apoC-II transgene may have alterations in the expression/activity of endogenous LPL in the heart. Furthermore, the decrease of LPL activity in the heart, along with the inhibitory effects of excess apoC-II, may contribute to the hypertriglyceridemia observed in apoC-II transgenic mice.
Impacts of Welfare Reform on Rural Families and Implications for the Reauthorization Debate: Discussion

that, compared to urban areas, rural labor is less educated, has fewer work support services, has more low-wage, part-time and seasonal jobs, and unemployment rates are higher.1 Whereas emphasizing the importance of labor supply impacts from welfare reform, Weber, Duncan and Whitener make the critical connection between place and people prosperity by concluding that new labor demand policies are needed that target lagging places. In effect, Weber, Duncan and Whitener suggest the new PRWORA needs a demand side complement to the existing work requirements and work support programs. "Big government" fears aside, this suggestion is supported by research that shows short-run wage subsidies for small businesses and public employment have improved earnings of low-income households over the long term (Bartik). Whereas the case for allocating some portion of the TANF block grants in the reauthorization to "lagging place" labor demand policies needs to be explored carefully, the Weber, Duncan and Whitener article provides support for a "place prosperity" policy to complement the PRWORA. Davis and Weber examine how low-income
1,1,n,n-Tetramethyl[n](2,11)teropyrenophanes (n = 7–9): a series of armchair SWCNT segments

A new iterative bridge formation strategy has been employed in the synthesis of a series of [n](2,11)teropyrenophanes (n = 7–9). The generation of the nonplanar teropyrene system, which is calculated to be bent through 178.7° for the smallest homologue (n = 7), is accomplished using a VID reaction of a cyclophanemonoene precursor for the first time.
ENHANCEMENT EFFECTS ON SENSORY AND RETAIL DISPLAY CHARACTERISTICS OF BEEF ROUNDS

Beef round roasts were injected (to 110% of original weight) to result in 0.4% sodium chloride and 0.4% phosphate on a finished weight basis. Steaks from enhanced roasts were more (P<0.05) juicy, tender and salty than those from control roasts. However, enhancement had a detrimental effect on the color of the steaks during retail display. After two days in display, enhanced steaks had lower visual color scores indicating darkening and discoloration. At 4 days, a* and b* values were lower for enhanced steaks indicating that they were less red and yellow than controls. Aerobic plate counts suggested that enhanced steaks were more susceptible to microbial growth during retail display. Although enhancement positively affected sensory characteristics, the negative effect of a shortened shelf-life was apparent.
Toward hyperspectral face recognition

Face recognition continues to meet significant challenges in reaching accurate results and still remains one of the activities where humans outperform technology. An attractive approach in improving face identification is provided by the fusion of multiple imaging sources such as visible and infrared images. Hyperspectral data, i.e. images collected over hundreds of narrow contiguous light spectrum intervals constitute a natural choice for expanding face recognition image fusion, especially since it may provide information beyond the normal visible range, thus exceeding the normal human sensing. In this paper we investigate the efficiency of hyperspectral face recognition through an in house experiment that collected data in over 120 bands within the visible and near infrared range. The imagery was produced using an off the shelf sensor in both indoors and outdoors with the subjects being photographed from various angles. Further processing included spectra collection and feature extraction. Human matching performance based on spectral properties is discussed.
A size and position invariant event-based human posture recognition algorithm

In this paper we report a size and position invariant human posture recognition algorithm. The algorithm employs a simplified line segment Hausdorff distance classification and uses projection histograms to achieve size and position invariance. Compared to other existing method utilizing line segment Hausdorff distance, the proposed algorithm reduces the computation complexity by 36000 times, for our test images. Combining bio-inspired event-based image acquisition and hardware friendly feature extraction and classification algorithm will lead to a promising technology for use in wireless sensor network.
SELECTIVE PROTECTION OF THE VARIOUS HYDROXY GROUPS OF CHOLIC ACID AND DERIVATIVES. A REVIEW

(1999). SELECTIVE PROTECTION OF THE VARIOUS HYDROXY GROUPS OF CHOLIC ACID AND DERIVATIVES. A REVIEW. Organic Preparations and Procedures International: Vol. 31, No. 2, pp. 145-166.
MIMO Radar Ambiguity Properties and Optimization Using Frequency-Hopping Waveforms

The concept of multiple-input multiple-output (MIMO) radars has drawn considerable attention recently. Unlike the traditional single-input multiple-output (SIMO) radar which emits coherent waveforms to form a focused beam, the MIMO radar can transmit orthogonal (or incoherent) waveforms. These waveforms can be used to increase the system spatial resolution. The waveforms also affect the range and Doppler resolution. In traditional (SIMO) radars, the ambiguity function of the transmitted pulse characterizes the compromise between range and Doppler resolutions. It is a major tool for studying and analyzing radar signals. Recently, the idea of ambiguity function has been extended to the case of MIMO radar. In this paper, some mathematical properties of the MIMO radar ambiguity function are first derived. These properties provide some insights into the MIMO radar waveform design. Then a new algorithm for designing the orthogonal frequency-hopping waveforms is proposed. This algorithm reduces the sidelobes in the corresponding MIMO radar ambiguity function and makes the energy of the ambiguity function spread evenly in the range and angular dimensions.
Behavior as a tool for assessing a managed landscape : a case study of the Karner blue butterfly

In an increasingly human-dominated landscape, effective management of disturbance-maintained ecosystems, such as grasslands and savannas, is critical to the conservation of biodiversity. Yet, the response of individual organisms to landscapes created by disturbances and management is rarely studied. In this study, we examined the endangered Karner blue butterfly, Lycaeides melissa samuelis, in a heterogeneous oak savanna. Our objective was to quantify the butterfly’s habitat use and behavior to assess the effects of prescribed burning. The oak savanna management in Ohio, USA divides each Karner blue site (n = 4) into three units. Each one-third unit is then burned, mowed, or unmanaged in an annual rotation within each site, and the result is a fire return interval of ~3 years. Our surveys measured habitat use, while behavior observations quantified reproduction and foraging for the two annual broods. Our habitat use results showed burned treatments were recolonized quickly, but there was not a clear selection for burned treatments. Foraging rates were similar in all treatments; however, females oviposited significantly less in unmanaged treatments (only 5 of 127 ovipositions). This oviposition preference was likely due to habitat degradation and the availability of recently burned, early successional habitat. Since Karner blues avoided reproduction in units unburned for ≥4 years, these units could be burned to create high quality early successional habitat. These results demonstrate how behavioral decisions can be pivotal forces driving spatial population dynamics. Our case study demonstrates how a fine-scale landscape perspective combined with measurements of behavioral processes can assist with management decision-making.
Near-Earth Asteroid Surveys

To date, more than 700 Near-Earth Asteroids have been discovered; of those, ~290 are estimated to be larger than 1 km in diameter. We estimate the total population of NEAs > 1 km to be ~1600. Present surveys are covering about half of the available sky each month to a limiting magnitude of ~19.0, resulting in about 20 discoveries per month of all sizes, including about 6 larger than 1 km diameter. This is about a factor of eight less than the discovery rate required to accomplish the Spaceguard Goal of discovering 90% of all NEAs larger than 1 km in diameter in ten years. We estimate that this goal will require an all-sky survey to a limiting magnitude of 20.5.
Predicting occurrences of acute hypoglycemia during insulin therapy in the intensive care unit

As intensive care units (ICUs) implement more intense insulin therapy to achieve tighter glycemic control, the risk for ICU patients to experience acute hypoglycemia increases. This study aims to develop a new method for predicting the occurrences of acute hypoglycemia during intravenous (IV) insulin infusion before the actual hypoglycemic events take place. Data from 3116 adult ICU patients have been retrospectively analyzed to elucidate glycemic dynamics and to devise a methodology for proactive prediction of acute hypoglycemic events in the ICU. Mutual information, embedded selection by classification trees, and odds ratios of categorized clinical time-series and occurrences of acute hypoglycemia were used to compare features of patients' glycemic dynamics. Classification tree learning was then applied to key features to generate predictive models of acute hypoglycemia. Results show that the two most recent blood glucose measurements and the slope of recent changes in blood glucose concentration with respect to the change in insulin infusion are the most informative features. Classification tree models built upon the key features accurately predicted 82.12% of acute hypoglycemic events (specificity: 89.87%; positive predictive value: 88.72%; accuracy: 86.00%) and 76.99% of severe acute hypoglycemic events (80.53%, 74.31%, and 78.76% respectively). The mechanistic approach developed in this study could be useful to discovering and understanding trends in clinical data leading up to acute hypoglycemia.
A look at cycles containing specified elements of a graph

This article is intended as a brief survey of problems and results dealing with cycles containing specified elements of a graph. It is hoped that this will help researchers in the area to identify problems and areas of concentration.
Majority Decisions and Transitivity: Some Special Cases

The problem considered is that of obtaining majority decisions which are transitive. We show that the corresponding optimization problems for the weighted l1 norm and the weighted l2 norm are identical. We then show that she general problem of minimizing the weighted lk norm can be equivalently formulated as a set covering problem. Finally, we identify the Tchebycheff problem l2 norm with a class, of bottleneck quadratic assignment problems and give an efficient algorithm for solving it.
Beyond Geography: Africa and Colonial Time in Who Knows Tomorrow

During the summer of 2010 the cityscape of Berlin became an important site for contemplating the role and meaning of "Africa" in current exhibitionand art-making practices. Who Knows Tomorrow , a multivenue exhibition organized by the Nationalgalerie, moved beyond multicultural celebrations of globalism and the overarching geographic and spatial taxonomies that still dominate most African art exhibitions. Instead, the exhibition foregrounded the ambiguous presence of colonial time in the analysis of Africa by emphasizing temporal interconnections and transitional moments. By refusing to emphasize geography or identity as categories of analysis, Who Knows Tomorrow promises an alternative logic for the study of Africa's relation to the world, suggesting new modes of interpretation that begin to acknowledge the disquiet that the coloniality of modernity continues to reproduce in the study of African cultural production.
Assessment of fixatives, fixation, and tissue processing on morphology and RNA integrity.

Molecular characterization of morphologic change requires exquisite tissue morphology and RNA preservation; however, traditional fixatives usually result in fragmented RNA. To optimize molecular analyses on fixed tissues, we assessed morphologic and RNA integrity in rat liver when sections were fixed in 70% neutral-buffered formalin, modified Davidson’s II, 70% ethanol, UMFIX, modified Carnoy’s, modified methacarn, Bouin’s, phosphate-buffered saline, or 30% sucrose. Each sample was subjected to standard or microwave fixation and standard or microwave processing, and sections were evaluated microscopically. RNA was extracted and assessed for preservation of quality and quantity. Modified methacarn, 70% ethanol, and modified Carnoy’s solution each resulted in tissue morphology representing a reasonable alternative to formalin. Modified methacarn and UMFIX best preserved RNA quality. Neither microwave fixation nor processing affected RNA integrity relative to standard methods, although morphology was modestly improved. We conclude that modified methacarn, 70% ethanol, and modified Carnoy’s solution provided acceptable preservation of tissue morphology and RNA quality using both standard and microwave fixation and processing methods. Of these three fixatives, modified methacarn provided the best results and can be considered a fixative of choice where tissue morphology and RNA integrity are being assessed in the same specimens.
Glucocorticoid Inhibition of Transcription from Adenovirus Major Late Promoter

Glucocorticoids inhibit proliferation of lymphosarcoma P1798 cells in culture. This is accompanied by inhibition of expression of class I as well as some class II genes. We have used the technique of transcription in vitro and the adenovirus major late promoter (AdMLP) to investigate molecular mechanisms of glucocorticoid inhibition of transcription of class II genes. Nuclear extracts from exponentially growing P1798 cells support faithful transcription from AdMLP. However, treatment of P1798 cells with 10−7 m dexamethasone (a synthetic glucocorticoid) for 24 h impairs the ability of nuclear extracts prepared from such cells to support faithful transcription from AdMLP. Transcription from the human histone H4 gene promoter is unaffected by dexamethasone treatment. Gel mobility shift assays using synthetic oligonucleotide probe indicate no difference in the CAAT box binding activity of control and dexaethasone-treated cell extracts. Similarly, dexamethasone treatment does not affect the upstream stimulator...
Progress on understanding spatial and temporal variability of PM2.5 and its components in the Detroit Exposure and Aerosol Research Study (DEARS)

The Detroit Exposure and Aerosol Research Study (DEARS) measured personal exposures, ambient, residential indoor and residential outdoor concentrations of select PM2.5 aerosol components (SO4, NO3, Fe, Si, Ca, K, Mn, Pb, Zn, EC and OC) over a three year period (2004–2007). These events represented approximately 190 calendar days of monitoring which was performed in seven residential neighborhoods throughout Wayne County, MI. The selection of neighborhoods and participants for study inclusion was based upon an a priori hypothesis that each neighborhood represented a potentially distinct air quality scenario being influenced by both regional as well as local pollution sources. Daily (24 h integrated) measurement data were used to evaluate the spatial and temporal PM2.5 compositional variability of the personal, indoor and outdoor spatial settings as they related to a central ambient monitoring site (Allen Park). Many of the PM2.5 components were observed to have spatially different outdoor mass concentrations in matched neighborhood by neighborhood comparisons, with sulfate, OC, and NO3 being noted exceptions. Coefficient of divergence (COD) comparisons involving outdoor measures for Ca, Si, Fe, Zn, Pb, and EC revealed significant spatial variability. While concentrations of most components were lower indoors as compared to outdoor measures, K and Si indoor concentrations often reflected aerosol enrichment (indoor/outdoor ratios ≥ 1.2). Even when personal exposures were adjusted for day to day changes in ambient concentrations, certain components (Ca, Fe, Mn, Zn, among others) revealed a high degree of location-specific spatial variability suggesting the influences of personal activities and/or local source influences on total personal PM2.5 exposures. As a whole, findings indicate that reliance on a central ambient monitor as a surrogate for total personal and potentially even residential outdoor estimates of PM2.5 aerosol composition may provide an undesirable degree of exposure uncertainty for health-based risk estimates. The focus of this paper is on the spatial variability and uncertainty in using a central monitoring site to estimate exposures. Additional information concerning the DEARS can be found at http://www.epa.gov/DEARS/.
Precision Machining Application and Technology: An Overview and Perspective.

After presenting a rule of thumb to evaluate the economical benefit of diamond turning compared to conventional polishing, applications of spinner mirrors, injection molding masters, and X-ray optics are discussed. Non-optical applications are included as well as precision grinding materials incompatible with diamond turning. KEY WORDS: Diamond Turning, Precision Machining, Precision Grinding, Quartz Grinding, X-ray Optics.
Teaching Human Evolution.

A \ s science educators, we have two goals in writing this paper. The first is to show the importance of teaching human evolution to all students. The second is to provide up-to-date resources for classroom teachers to use in teaching the subject. Secondary biology textbooks suffer from the inherent limitations of mass produced books making it difficult for them to stay current with rapidly changing scientific fields such as paleoanthropology. One of our motives for writing this paper is to compensate for this inherent limitation of textbooks.
Multilaboratory Testing of Antifungal Drug Combinations against Candida Species and Aspergillus fumigatus: Utility of 100 Percent Inhibition as the Endpoint

Four laboratories tested three isolates of Candida species and two isolates of Aspergillus fumigatus using 96-well plates containing combinations of amphotericin B, anidulafungin, caspofungin, micafungin, fluconazole, itraconazole, posaconazole, and voriconazole. The majority of summation fractional inhibitory concentration indices (ΣFICI) based on the Lowe additivity formula suggested indifferent drug interactions (ΣFICI > 0.5 and ≤4.0) and no instance of drug antagonism (ΣFICI > 4.0). The intra- and interlaboratory agreement rates were superior when MIC100 readings were used as endpoints (at a 99% confidence interval [CI]).
An analysis of TCP over random access satellite links

This paper analyzes the performance of TCP over satellite links with random access. The system considered consists of large number of identical source-destination pairs, each employing TCP at its transport layer and a random access scheme at its MAC layer. Simple formulas that well capture the system performance are given, and some important properties of the system performance are presented as well. Specifically, in order to analyze the system and proposes a simplified version of the system. Then formulas were developed for obtaining the throughput of this simplified system as a function of various system and protocol parameters. Based on these formulas, it is shown that the maximum possible system throughput is 1/e, which can be achieved only when the system parameters satisfy a given condition. The optimal MAC layer transmission probability at which the throughput is maximized is derived as well. Furthermore, the impact of varying system and protocol parameters on the system performance is analyzed. The results show that for systems with very small propagation delay or very large number of source-destination pairs, a throughput of 1/e can be achieved by setting the MAC layer transmission probability to its optimal value. However, when the number of users is (relatively) small or the propagation delay is (relatively) large, the maximum achievable throughput can be substantially smaller than 1/e. Although the analysis is based on the simplified system, simulations on the original system show that the formulas and the above results can be used to describe the performance of the original system as well.
Incremental Change or Initial Differences? Testing Two Models of Marital Deterioration

Most couples begin marriage intent on maintaining a fulfilling relationship, but some newlyweds soon struggle, and others continue to experience high levels of satisfaction. Do these diverse outcomes result from an incremental process that unfolds over time, as prevailing models suggest, or are they a manifestation of initial differences that are largely evident at the start of the marriage? Using 8 waves of data collected over the first 4 years of marriage (N 502 spouses, or 251 newlywed marriages), we tested these competing perspectives first by identifying 3 qualitatively distinct relationship satisfaction trajectory groups and then by determining the extent to which spouses in these groups were differentiated on the basis of (a) initial scores and (b) 4-year changes in a set of established predictor variables, including relationship problems, aggression, attributions, stress, and self-esteem. The majority of spouses exhibited high, stable satisfaction over the first 4 years of marriage, whereas declining satisfaction was isolated among couples with relatively low initial satisfaction. Across all predictor variables, initial values afforded stronger discrimination of outcome groups than did rates of change in these variables. Thus, readily measured initial differences are potent antecedents of relationship deterioration, and studies are now needed to clarify the specific ways in which initial indices of risk come to influence changes in spouses’ judgments of relationship satisfaction.
Current approaches to macromolecular crystallization.

Given our current expertise, and the certain future developments in genetically altering organisms to produce proteins of modified structure and function, the concept of protein engineering is nearing reality. Similarly, our ability to describe and utilize protein structure and to define interactions with ligands has made possible the rational design of new drugs and pharmacological agents. Even in the absence of any intention toward applied use or value, the correlation of regulation, mechanism, and function of proteins with their detailed molecular structure has now become a primary concern of modern biochemistry and molecular biology. At the present time, there are numerous physical-chemical approaches that yield information regarding macromolecular structure. Some of these methods, such as NMR and molecular dynamics, are becoming increasingly valuable in defining detailed protein structure, particularly for lower-molecularmass proteins. There is, however, only one general technique that yields a detailed and precise description, in useful mathematical terms, of a macromolecule’s structure, a description that can serve as a basis for drug design, and an intelligent guide for protein engineering. The method is X-ray diffraction analysis of single crystals of proteins, nucleic acids, and their complexes with one another and with conventional small molecules. Some inspirational examples of representative crystals are shown in Fig. 1 - 3. In the past 20 years, the practice of X-ray crystallography has made enormous strides. Nearly all of the critical and timeconsuming components of the technique have been improved, accelerated, and refined. X-ray crystallography today is not simply an awesome method used by physical chemists to reveal the vast beauty of macromolecular architecture; it is a practical, reliable, and relatively rapid means to obtain straightforward answers to perplexing questions. X-ray diffraction data that once required years to obtain, can now be collected in a matter of weeks, even days in some cases. Computers of extraordinary speed and capacity are now common tools as are computer graphics systems of a versatility and cleverness that would have been unimaginable only a few years ago. Software, too, exists that is sophisticated yet friendly, flexible yet reliable, and readily available to anyone in need of it. The question, then, is where does the problem lie? What prevents the full utilization and exploitation of this enormously powerful approach. The answer, of course, is that for application of the method to a particular macromolecule, the protein or nucleic acid
THE CLIMATE FOR WOMEN IN ACADEMIC SCIENCE: THE GOOD, THE BAD, AND THE CHANGEABLE

Deficits theory posits that women scientists have not yet achieved parity with men scientists because of structural aspects of the scientific environment that provide them with fewer opportunities and more obstacles than men. The current study of 208 faculty women scientists tested this theory by examining the effect of personal negative experiences and perceptions of the workplace climate on job satisfaction, felt influence, and productivity. Hierarchical multiple regression results indicated that women scientists experiencing more sexual harassment and gender discrimination reported poorer job outcomes. Additionally, perceptions of a generally positive, nonsexist climate, as well as effective leadership, were related to positive job outcomes after controlling for harassment and discrimination. We discuss implications for the retention and career success of women in academic science.
A parallel approach in switchbox routing

A parallel algorithm, called PARALLEX, has been developed for the switchbox routing problem. The algorithm can be easily implemented on a shared-memory multiprocessor system. Since the algorithm is general-purpose in nature, it can be applied to a variety of routing problems. The number of processes is equal to the number of nets; each process has its own net to be routed. All the nets routed by individual processes are merged to make a conflict-free switchbox. Any conflicts occurring in the merging stage are grouped by conflict nets. From the conflict group belonging to the process each process finds its own solution, which is to be merged with the solutions from other conflict groups. A large-grain parallelism is possible by using as many processes as nets. >
BUILDING A LATINO‐ENGAGED ACTION‐RESEARCH COLLABORATIVE: A CHALLENGING UNIVERSITY–COMMUNITY ENCOUNTER

This article discusses the experience of the Nuevo South Action-Research Collaborative, a university–community collaborative involving an interdisciplinary group of faculty and students from East Carolina University and Latino community organizations. The article describes the collaborative formation process and places it within the context of the southeast as a new destination for Latino immigration. The collaborative formation process is discussed from the point of view of a complex encounter characterized by concurrences and tensions.
The effect of fish meal replacement by soyabean products on fish growth: a meta-analysis

Meta-analysis was applied to quantify the effect of replacement of fish meal by soyabean products in diets on fish growth. Measurement of growth in different units among studies required the use of a standardised effect size (Hedges' d). From a total of ninety-nine studies concentrating on fish meal replacement by defatted soyabean meal, 53 % were eliminated due to, among others, absence of a fish meal control diet (n 18), or no statistical differences or measurement of dispersion (n 6) indicated. Replacement of 4 to 40 % fish meal by soyabean meal (inclusion levels of 71-366 g/kg) resulted in a mean effect size of - 0.1142 (95 % CI - 0.4665, 0.2382) obtained in forty-eight comparisons evaluated with seventeen different fish species. However, at higher fish meal replacement levels the 95 % CI calculated for combined effect sizes did not overlap with zero. With soya protein concentrate replacing 25 to 100 % of fish meal in diets for seven fish species, methionine supplementation (mean - 2.4373 (95 % CI - 3.9004, - 0.9742); n 10) did not have a substantial influence on the magnitude of cumulative effect sizes relative to no supplementation (mean - 2.7306 (95 % CI - 3.7991, - 1.6620); n 16). Information on other soyabean products (full-fat soyabeans, soya flour) used as protein sources in fish diets was found as too limited for analysis and definite conclusions. The present study contributes by putting a numerical value to the magnitude of growth differences in fish when replacing dietary fish meal by soyabean products.
A methodology for robust, energy efficient design of Spin-Torque-Transfer RAM arrays at scaled technologies

In this paper we propose a methodology for energy efficient Spin-Torque-Transfer Random Access Memory (STTRAM) array design at scaled technology nodes. We present a model to estimate and analyze the energy dissipation of an STTRAM array. The presented model shows the strong dependence of the array energy on the silicon transistor width, word line voltage and row/column organization. Using the array energy model we propose a design methodology for STTRAM arrays which minimizes the energy dissipation while maintaining the required robustness in read and write operations at scaled technologies.
UV-activated conductances allow for multiple time scale learning

Ultraviolet (UV) photoinjection of electrons through SiO/sub 2/ provides a convenient and simple method for programming analog, nonvolatile memories in CMOS circuits. The time scales involved in the UV programming process are well suited to multiple time scale learning algorithms providing several orders of magnitude in programming rate. The method requires no special processing technology. Measured characteristics of the UV photoinjection devices and experimental results from a synapse circuit built using these devices are presented. This synapse circuit includes a continuously adjustable weight, an electronic learn/hold control and slow forgetting dynamics, while allowing an unimpeded multiplication operation at all times. >