cssi/SciSciGPT-SciSciNet huggingface dataset:
Chinese immigrant population history in North America based on craniometric diversity

In this study, Chinese immigrant population history and structure was assessed using craniometric diversity in two historic cemeteries located in North America. Analyses addressed questions of population history, migration, and geographic origin for Chinese immigrants to the United States in the late 1800s. Craniometric diversity was assessed by the use of the R-matrix method on 19 metric traits in 62 male Chinese immigrant individuals. Using a population genetic model (Relethford–Blangero), our results indicate a low level of genetic diversity for these Chinese immigrants. Principal coordinate plots and neighbor-joining trees based on the morphological distances transformed from the R-matrix showed that the Chinese immigrant sample clusters closest to known East Asian populations. Further, we substantiate the biological origin for the Chinese immigrants as coming from South China. A historical reading suggests that the majority of Chinese emigrating to the United States departed and were born in southern China. Biological distances for the Chinese immigrants are more similar to samples from Guangdong Province and surrounding areas than to regions in North China. Identification bricks (grave markers) recovered during excavation in Nevada revealed two individuals born in Tai’shan, a city located along the Pearl River Delta and west of Hong Kong, a port used by Westerners during the late 19th century and used as a point of departure for many emigrating from mainland China. This evidence supports the historical and archaeological record and confirms the use of craniofacial variability to answer questions of population history and structure. This study is the first to assess Chinese immigrant population history using biological data.
Vitamin D metabolite profiles in moderate renal insufficiency of childhood.

In a prior study, we reported vitamin D metabolite profiles in the plasma of healthy children. In view of these findings, we investigated these same profiles in children with moderate renal insufficiency. Specimens were obtained in boty summer and winter in untreated patients, and before and after treatment for up to 1 year, with either 25(OH)D3 or 1,25(OH)2D3. Mean pretreatment 1,25(OH)2D levels were normal. Levels of 25(OH)D3 were also normal and continued to vary with season. Mean pretreatment 24,25(OH)2D3 levels were significantly lower in patients and, interestingly, did not show the normal seasonal variation. Treatment with 25(OH)D3 resulted in consistent and sustained rises in 25(OH)D3 and 24,25(OH)2D3 levels, but no increase in 1,25(OH)D3 levels. After 1,25(OH)2D3 treatment, 25(OH)D3 levels were unchanged but still showed seasonal variation in some patients, suggesting a lack of feedback control by 1,25(OH)2D3. Levels of 24,25(OH)2D3 were not significantly different from baseline values. Levels of 1,25(OH)2D increased initially then dropped to pretreatment levels or lower. Normal 1,25(OH)2D levels and reduced 24,25(OH)2D3 levels with the loss of seasonal variation suggests in our patients that the kidney was able to maintain 1,25(OH)2D levels at the expense of 24,25(OH)2D3 levels, presumably to preserve calcium homeostasis.
Sodium bicarbonate ingestion improves performance in interval swimming.

In an effort to determine the effects of bicarbonate (NaHCO3) ingestion on exercise performance, ten male college swimmers were studied during five different trials. Each trial consisted of five 91.4m (100-yd) front crawl swims with a two-minute rest interval between each bout. The trials consisted of two NaHCO3 treatments, two placebo trials and one test with no-drink. One hour before the onset of swimming, the subjects were given 300 ml of citric acid flavored solution containing either 17 mmol of NaCl (placebo) or 2.9 mmol of NaHCO3 · kg−1 body weight (experimental), or received no drink (no-drink). Performance times for each 91.4 m swim were recorded. Blood samples were obtained before and one hr after treatment, two min after warmup, and two min after the final 91.4 m sprint. Blood pH, lactate, standard bicarbonate (SBC) and base excess (BE) were measured. No differences were found for performance or the blood measurements between the placebo and no-drink trials. Bicarbonate feedings, on the other hand, produced a significant (P<0.05) improvement in performance on the fourth and fifth swimming sprints. Blood lactate, pH, SBC and BE were significantly higher (P<0.05) at post-exercise in NaHCO3 treatments. These data are in agreement with previous findings that during repeated bouts of exercise pre-exercise administration of NaHCO3 improves performance, possibly by facilitating the efflux of hydrogen ions from working muscles and thereby delaying the onset of fatigue.
Rational power series, sequential codes and periodicity of sequences

Abstract Let R be a commutative ring. A power series f ∈ R [ [ x ] ] with (eventually) periodic coefficients is rational. We show that the converse holds if and only if R is an integral extension over Z m for some positive integer m . Let F be a field. We prove the equivalence between two versions of rationality in F [ [ x 1 , … , x n ] ] . We extend Kronecker’s criterion for rationality in F [ [ x ] ] to F [ [ x 1 , … , x n ] ] . We introduce the notion of sequential code which is a natural generalization of cyclic and even constacyclic codes over a (not necessarily finite) field. A truncation of a cyclic code over F is both left and right sequential (bisequential). We prove that the converse holds if and only if F is algebraic over F p for some prime p . Finally, we show that all sequential codes are obtained by a simple and explicit construction.
Absence of defects in SPECT thallium-201 myocardial images in patients with systemic hypertension and left ventricular hypertrophy

Abstract Hypertension is common in patients undergoing stress and delayed single-photon emission computed tomography (SPECT) thallium-201 myocardial perfusion imaging. Investigators have reported that patients with end-stage renal disease and left ventricular hypertrophy due to hypertension have diminished lateral/septal count ratios on stress and delayed imaging mimicking lateral myocardial infarction in approximately 35% of patients. Subsequently, hypertension has been cited as a frequent cause of thallium-201 artifacts. The purpose of this study was to compare myocardial SPECT thallium-201 distribution in a broader group of patients with left ventricular hypertrophy resulting from hypertension with normal file subjects in order to determine the prevalence of abnormal studies and to compare the lateral/septal count ratio. Average counts in all myocardial regions in the male study group (n = 16) were compared with those in the normal male file patients (n = 49), with particular attention to the lateral and septal walls. In the group of 16 men with hypertension and left ventricular hypertrophy, as a whole, the mean lateral/septal wall count ratio was 4.4% tower (1.09 ± 0.07) than that in the normal file (1.14 ± 0.07; p 2.0 SD below normal limits. All thallium-201 studies were interpreted as normal. In conclusion, myocardial thallium-201 distribution is normal in patients with left ventricular hypertrophy due to hypertension.
Polymerization of the SAM domain of TEL in leukemogenesis and transcriptional repression.

TEL is a transcriptional repressor that is a frequent target of chromosomal translocations in a large number of hematalogical malignancies. These rearrangements fuse a potent oligomerization module, the SAM domain of TEL, to a variety of tyrosine kinases or transcriptional regulatory proteins. The self-associating property of TEL–SAM is essential for cell transformation in many, if not all of these diseases. Here we show that the TEL–SAM domain forms a helical, head-to-tail polymeric structure held together by strong intermolecular contacts, providing the first clear demonstration that SAM domains can polymerize. Our results also suggest a mechanism by which SAM domains could mediate the spreading of transcriptional repression complexes along the chromosome.
Look out-it's your off-peak time of day! Time of day matters more for alerting than for orienting or executive attention.

Background/Study Context: Older adults’ peak performance on memory and cognitive inhibition tasks tends to be in the morning, whereas younger adults’ peak performance tends to be in the afternoon. Although these tasks require efficient attentional processes for optimal performance, previous research examining age differences in the effects of time of day has not measured the distinct aspects of attention quantified by the Attention Network Test (ANT; Fan, McCandliss, Sommer, Raz, & Posner, 2002, Journal of Cognitive Neuroscience, 14, 340–347). Methods: The authors examined the relationship between time of testing and the efficiency of alerting, orienting, and executive attention networks by randomly assigning younger (18–28 years; n = 27, M = 21.37 years, SD = 2.39) and older (65–85 years; n = 32, M = 73.34 years, SD = 5.18) adults to morning (AM) or afternoon (PM) testing of alerting, orienting, and executive attention. Mean reaction times for each network were analyzed with a univariate analysis of vari...
ALL: Automated learning laboratory

ALL is a CAI package designed to give students “hands-on” experience with a primitive learning laboratory. Using ALL, students can serve as either research subjects or experimenters. Both schedules of reinforcement and the nature of the reinforcer may be varied within the program for a number of simple learning tasks.
ΔΣ ADC Design Considerations for WiFi/WiMAX Receivers

Modern multi-standard receivers in deep-submicron technologies pose significant design challenges on the analog baseband. Moving this analog filtering to the digital domain simplifies the design, yielding a process-scalable implementation. However, analog-to-digital converter (ADC) specifications now become more stringent and must be obtained by comprehending the standard and the system. Assuming a receiver NF of 5.96dB and SNR degradation of 0.36dB by the ADC, the proposed dual-mode WiFi/WiMAX receiver attains an input sensitivity of -74dBm (20MHz channel bandwidth). To accommodate the high dynamic range and the anti-alias rejection needed for the system, a Delta-Sigma (ΔΣ) ADC is proposed. Single-loop and Multi-Stage Noise-Shaping (MASH) architectures that achieve a SNR of 69dB at a low oversampling ratio (OSR) of 8 for a conversion bandwidth of 40MHz (108Mbps, OFDM) are investigated. Based on the important insights from this analysis on thermal noise, harmonic distortion, and power tradeoffs, an optimal ΔΣ ADC design is proposed.
Stability of Three-Dimensional Motions in a Combustion Chamber

The problem oflinearized three-dimensional motions in a non-uniform flowfield is re-examined. Several modifications of the general analysis are effected: The influence of particulate matter is acounted for, to zeroth order, and certain boundary processes treated in earher one-dimensional computations are incorporated in an analysis applicable to any geometry. All processes occurring in combustion chambers are accommodated. As a specific example, the results are applied to a problem of linear stability in solid propellant rocket motors.
Paradigms of doom and the development management crisis in Kenya

Public Enterprise in Kenya: What Works, What Doesn't and Why. By Barbara Grosh. Boulder, CO and London: Lynne Reinner Publishers, 1991. Pp.223. $45. ISBN 1 55587 209 3 The Culture of Politics in Modern Kenya. By Angelique Haugerud. Cambridge and New York: Cambridge University Press, 1995. Pp.265. $59.95 ISBN 0 521 47059 5 Kenyan Capitalists, the State and Development. By David Himbara. Boulder, CO and London: Lynne Reinner Publishers, 1994. Pp.191. $40. ISBN 1 55587 430 4 African Successes: Four Public Managers of Kenyan Rural Development. By David K. Leonard. Berkeley, CA and London: University of California Press, 1991. Pp.364. $19.95. ISBN 0 520 07075 5
Platform Leadership: Cultivating Support for a Public Profile

The authors identify and describe a distinct type of social movement leadership, oriented toward promotion of a distinct position or set of arguments rather than toward any kind of grassroots mobil...
On k-Median clustering in high dimensions

We study approximation algorithms for k-median clustering. We obtain small coresets for k-median clustering in metric spaces as well as in Euclidean spaces. Specifically, in Rd, those coresets are of size with only polynomial dependency on d. This leads to a (1 + e)-approximation algorithm for k-median clustering in Rd, with running time O(ndk +2(k/e)o(1)d2nσ), for any σ > 0. This is an improvement over previous results [5, 20, 21]. We also provide fast constant factor approximation algorithms for k-median clustering in finite metric spaces.We use those coresets to compute (1 + e)-approximation k-median clustering in the streaming model of computation, using only O(k2de-2log8n) space, where the points are taken from Rd. This is the first streaming algorithm, for this problem, that has space complexity with only polynomial dependency on the dimension.
Creativity and intelligence in preschoolers

This study examined the relationship between creativity and intelligence in preschoolers. Four hundred and ninety-six children for whom parents were seeking admission to a program for bright or gif...
PHOSPHORUS AND MAGNESIUM BALANCE OF ADOLESCENT FEMALES FED TWO LEVELS OF ZINC

Utilization of phosphorus and magnesium by 11 girls (12.5-14.2 yr of age) was measured during a 30-day period in which two different levels of zinc (11.5 and 14.7 mg daily) were fed. The former level is similar to that consumed usually by adolescent females; the latter level is similar to the Recommended Dietary Allowance for zinc. Apparent retention of phosphorus was reduced significantly (p < 0.02) when subjects were fed the higher level of zinc. Both urinary and fecal phosphorus levels were greater, but not significantly greater, when subjects consumed the higher level of zinc. The variations in dietary zinc levels had no effect on magnesium utilization.
Approaches to technological forecasting as a planning tool

Abstract The various techniques discussed in this paper illustrate to managers that a number of useful approaches are available to them for approaching planning problems. Not every technique discussed can be applied to all problems. Problems related to available time, money, and information for planning can limit the usefulness of some techniques. The successful manager in light of existing constraints will develop integrative forecasts that can be used to reduce the risks of making decisions under conditions of uncertainty.
Floral-stimulus activity in tobacco stem pieces

The growth patterns of axillary buds of dayneutral tobacco (Nicotiana tabacum L. cv. Wisconsin 38) plants were assessed by using expiants of single buds attached to leafless stem cuttings and allowing the buds to grow to flowering without additional manipulation. Buds located 5, 10 and 15 nodes below the inflorescence were employed. For a given bud position, when a cutting had few internodes the growth pattern of a bud tended to fall into one of two groups: buds that produced few-noded shoots and buds that produced many-noded shoots. For example, in a group of 13 cuttings composed of bud 5 with 2 associated internodes, 11 buds produced 14.2 nodes (range, 11–17) and 2 buds produced 32.0 nodes (range, 30–34). As the number of internodes on the cutting increased, the number of buds producing few-noded shoots increased and the number of nodes produced decreased (e.g. in contrast to the data above, all 5th buds with 6 internodes produced 12.8 nodes; range 11–15). When cuttings from the 3 positions had the same number of internodes, the more apical cuttings had buds that produced fewer nodes (e.g. for cuttings with 6 internodes all 5th buds produced 12.8 nodes, all 10th buds produced 15.5 nodes and 85% of 15th buds produced few-noded shoots with 19.3 nodes). The number of nodes produced by a bud was a function of the original position of the stem piece and not the original position of the bud. That is, bud 5 associated with the 6 internodes below it produced 12.8 nodes and bud 10 associated with essentially the same 6 internodes (i.e. the 6 above it) produced 12.9 nodes while bud 10 associated with the 6 internodes below it produced 15.5 nodes. Thus, the number of nodes produced by a bud was dependent upon the original main-axis position of the cutting as well as the number of internodes on the cutting. Buds forced to grow out in situ on main axes devoid of leaves produced substantially more nodes than similar buds on cuttings. Buds isolated without associated internodes produced many-noded plants with a number of nodes similar to that of plants grown from seed. The simplest interpretation of these data is that stem pieces contain floral-stimulus activity and that this activity is present in a gradient with the highest activity being located in the apical part of the stem.
Autoimmune thrombocytopenia in sarcoidosis

Severe thrombocytopenia and splenomegaly developed in a young man with sarcoidosis. Platelet-associated immunoglobulin (IgG) was strongly positive, and platelet survival studies revealed a half-life of five and a half hours. Treatment with prednisone and vincristine led to a rise in the platelet count to 100,000/mm3 after two months with no change in the splenomegaly. Five months later, when the platelet count was normal, the level of platelet-associated IgG had fallen to normal. Repeated platelet survival studies showed an initial half-life of three hours with a second half-life of two days, associated with accumulation in the spleen. Although there was evidence for splenic sequestration of platelets, the dominant mechanism of thrombocytopenia appeared to be antibody-mediated destruction, analogous to that seen in idiopathic autoimmune thrombocytopenic purpura and responsive to immunosuppressive therapy.
Some properties of the time-course stabilization of running behavior of rats living in activity wheel units.

It is important to have information about the duration of the adaptation period required for stable running rates in activity wheels both for planning the length of experiments and for scheduling treatments following the adaptation period. Much activity research circumvents problems of apparatus differences by using each animal as its own control, allowing treatment effects to be expressed as a percentage of the activity during the adaptation period (e.g., Finger, 1951). But such percentages are influenced by the extent to which activity stabilized during adaptation. If it were still increasing, for example, treatment effects would be confounded with the irscrease. Even if mean group running rates showed no significant slope across days, unstable individual rates could impair the sensitivity of an experiment by contributing variability. Discussions of the length of adequate adaptation periods leave the impression that 10 to 21 days suff~ce. Munn (1950, p. 77), citing Shirley (1928b), wrote "She claimed that at least ten days of adaptation to the cages are essential." Hall (1961, p. 116; cites another article by Shirley (1928a) to the effect that young rats "require just nine days to become adapted to the activity wheel and older animals (100 days of age) require 15 days." Hall also discusses the work of Eayrs (1954) showing that 21 days may be required but points out that Eayrs used females, whose estrus cycle may have made the lengthy adaptation period necessary. In the course of several experiments it became dear that, while individual running races did stabilize, time periods in excess of the above were required. SS were 23 male albino rats born of pregnant females supplied by the Holtzman Co. All Ss were reared from birth in a 12-hr. light/dark cycle until age 60 days, when they were put in enclosed Wahmann LC-34 activity wheel units which have a small living cage acached to an activity wheel. All wheels were equated for frictional torque (Lacey, 1944) and modified as suggested by Lockard ( 1965 ) . The same light/dark cycle and other laboratory conditions dining rearing continued. Each S lived in a unit for 135 days. The first 80 were an adaptation period with constant conditions of ad lib. food, water, and wheel. On Day 81 Ss were shut off from the wheel by a sliding door for 2 to 6 days, after which the door was open for the remainder of the experiment. The adaptation conditions then continued through Day 129, after which 6 days of either food or
Condition Monitoring With Round Ceramic Inserts While Face Milling Using Acceleration Data

In order to automate machining operations, it is necessary to develop robust tool condition monitoring techniques. In this paper, a tool monitoring strategy for round whisker-reinforced ceramic end milling tools is presented based on the Fourier transform and statistical analysis of the vibrations of the tool during the machining operations. Using a low-cost tri-axial piezoelectric accelerometer, the presented algorithm demonstrates the ability to accurately monitor the condition of the tools as the wear increases during linear milling operations. One benefit of using accelerometer signals to monitor the cutting process is that the sensor does not limit the machines capabilities, as a workpiece mounted dynamometer does. To demonstrate capabilities of the technique for round coated and uncoated ceramic tooling, six tool wear life tests were conducted under various conditions. The indirect method discussed herein successfully tracks the tool’s wear, even with the occurrence of minor chipping, and is shown to be sensitive enough to provide sufficient time to replace the insert prior to damage of the machine tool, cutter, and/or workpiece.Copyright © 2010 by ASME
SU-FF-T-38: Dosimetric Characteristics of a P-32 Conformal Source for Irradiation of Paraspinal Tumors

Purpose: A 90 Y foil encased in a titanium plaque has been used to irradiate the dura for patients with paraspinal tumors. The plaque is applied to the dura intraoperatively after radiotherapy and surgery. Rapid falloff of the %DD allows the dura's surface to be treated, while sparing the spinal cord a few millimeters below. A new plaque, the RIC Conformal Source, utilizing 32 P embedded in a polymeric film and bonded to a polycarbonate backing has been developed for surface irradiations. This new plaque has advantages over previous designs. The lower energy of 32 P (1.709 MeV) allows for increased dose sparing of the cord over 90 Y (2.28 MeV). Additionally, a longer half life of 14.28 days for 32 P versus 2.67 days for 90 Y , as well as a simpler manufacturing process make this new source worthy of investigation. Method and Materials: To study the dosimetriccharacteristics of this new plaque, a flat plaque was constructed for measurements with radiochromic film. Surface profiles and %DD were measured and compared to Monte Carlo (Penelope) data. The 32 P data was also compared to the 90 Y data to show viability of the new source for treatment. Surface profiles were evaluated using a Therapeutic Width Index (TWI), defined as the width of the surface profile at 90% divided by the width of the source.Results: The 32 P plaque's surface profiles and %DD measurements agreed well with Penelope. Comparison of %DD showed a more rapid falloff for 32 P (2.3% at 3mm) than for 90 Y (14.1% at 3mm). The TWI for 32 P was 0.82 and was 0.88 for the 90 Y . Conclusion: Better %DD characteristics and similar surface profiles show the new plaque utilizing 32 P to be clinically acceptable. Inhomogeneities in the polymeric film need to be further evaluated before clinical use of this source.
Ion exchange kinetics of fission products between molten salt and zeolite-A

Abstract Experimentation, data analysis, and modeling of ion exchange kinetics between fission products (cesium and strontium) and zeolite-A beads in molten LiCl–KCl have been performed to support optimization of an electrochemical process to treat used nuclear fuel. Models based on pseudo-first- and pseudo-second-order sorption as well as diffusion have been adapted and compared to experimental data to assess their validity in describing the system. Individual experiments were performed with different concentrations of CsCl or SrCl2 in the LiCl–KCl salt. Zeolite beads were removed from the molten salt at prescribed intervals of time and prepared for analysis by inductively coupled plasma-mass spectrometry. Results indicate maximum cesium (Cs) and strontium (Sr) loading occurred at approximately 31 min and 104 min of contact, respectively. The rate of loading and maximum loading were found to increase with increasing initial concentration of Cs or Sr. Data analysis included determination of rate constants and diffusion coefficients of the proposed models for each experimental condition. Results reveal that the diffusion model provides the best fit to the experimental data with average diffusion coefficients of 2.0 × 10−10 m2 s−1 for Cs and 6.3 × 10−11 m2 s−1 for Sr. This suggests that chemical diffusion is the dominant mechanism of mass transfer.
Surgical correction of Peyronie's disease via tunica albuginea plication or partial plaque excision with pericardial graft: long-term follow up.

ABSTRACT Introduction Limited publications exist regarding long‐term outcomes of surgical correction for Peyronie's Disease (PD). Aim To report on long‐term postoperative parameters including rigidity, curvature, length, sensation, function, and patient satisfaction in men with PD treated surgically via Tunica Albuginea Plication (TAP) or Partial Plaque Excision with Tutoplast® Human Pericardial Grafting (PEG). Main Outcome Measures Objective and subjective data regarding patients who underwent either TAP or PEG. Methods We report on 142 patients (61 TAP and 81 PEG) with both objective data and subjective patient reports on their postoperative experience. Patients underwent either TAP or PEG following our previously published algorithm. Data was collected via chart review and an internally generated survey, in which patients were asked about their rigidity, straightness, penile length, sensation, sexual function and satisfaction. Results Average follow up for TAP patients was 72 months (range 8–147) and 58 months (range 6–185) for PEG patients. At survey time, 93% of TAP and 91% of PEG patients reported curvatures of less than 30o. Rigidity was reportedly as good as or better than preoperative in 81% of TAP and 68% of PEG patients, and was adequate for coitus in 90% of TAP and 79% of PEG patients with or without the use of PDE5i. Objective flaccid stretched penile length measurements obtained pre and postoperatively show an average overall length gain of 0.6 cm (range −3.5–3.5) for TAP and 0.2 cm (range −1.5–2.0) for PEG patients. Sensation was reportedly as good as or better than preoperative in 69% of both TAP and PEG patients; 98% of TAP patients and 90% of PEG are able to achieve orgasm. 82% of TAP patients and 75% of PEG patients were either very satisfied or satisfied. Conclusion Our long‐term results support both TAP and PEG as durable surgical therapy for men with clinically significant PD. Taylor FL, and Levine LA. Surgical correction of Peyronie's disease via tunica albuginea plication or partial plaque excision with pericardial graft: Long‐term follow up. J Sex Med 2008;5:2221–2228.
Public sector employee voter participation and salaries

The hypothesis advanced by Downs (1957) that rational, utility-maximizing citizens would calculate the benefits and costs of voting in deciding whether to vote often has been employed to argue that voter participation rates among government employees should exceed that of comparable private sector individuals. The basic rationale for that prediction was laid out by Downs (1957: 254) who argued that "those who stand the most to gain are the men who earn their incomes there." Higher voter participation rates for government employees coupled with an implied preference for the expansion of the public sector has also played a role in efforts to explain the growth of government (Borcherding, Bush and Spann, 1977; and Bush and Denzau, 1977). In addition to benefiting from the supply of public goods and services, as do all voters, government employees are seen as benefiting from the expansion of government through an increase in their salaries. In this paper, the issue of voter participation rates for government employees is reexamined. Current Population Survey (CPS) data tapes containing information on individual voter behavior for the 1984 and 1986 national elections are used to estimate a qualitative choice model.1 Consistent with previous findings, the results presented indicate that government employees, as a group, are more likely to vote than are private sector workers with similar socioeconomic and demographic characteristics (Wolfinger and Rosenstone, 1980). Unlike previous studies, however, we distinguish between federal and state and local employees. This distinction is important. Building on the Downsian hypothesis that the cost and benefits of voting matter, the arguments offered in the following section lead to the prediction that the probability of voting should be lower for federal employees than for state and local. The empirical
Temperature invariance of the nitrogenase electron transfer mechanism.

Earlier studies of electron transfer (ET) from the nitrogenase Fe protein to the MoFe protein concluded that the mechanism for ET changed during cooling from 25 to 5 °C, based on the observation that the rate constant for Fe protein to MoFe protein ET decreases strongly, with a nonlinear Arrhenius plot. They further indicated that the ET was reversible, with complete ET at ambient temperature but with an equilibrium constant near unity at 5 °C. These studies were conducted with buffers having a strong temperature coefficient. We have examined the temperature variation in the kinetics of oxidation of the Fe protein by the MoFe protein at a constant pH of 7.4 fixed by the buffer 3-(N-morpholino)propanesulfonic acid (MOPS), which has a very small temperature coefficient. Using MOPS, we also observe temperature-dependent ET rate constants, with nonlinear Arrhenius plots, but we find that ET is gated across the temperature range by a conformational change that involves the binding of numerous water molecules, ...
Peripheral blood gene expression signature differentiates children with autism from unaffected siblings

Autism spectrum disorder (ASD) is one of the most prevalent neurodevelopmental disorders with high heritability, yet a majority of genetic contribution to pathophysiology is not known. Siblings of individuals with ASD are at increased risk for ASD and autistic traits, but the genetic contribution for simplex families is estimated to be less when compared to multiplex families. To explore the genomic (dis-) similarity between proband and unaffected sibling in simplex families, we used genome-wide gene expression profiles of blood from 20 proband-unaffected sibling pairs and 18 unrelated control individuals. The global gene expression profiles of unaffected siblings were more similar to those from probands as they shared genetic and environmental background. A total of 189 genes were significantly differentially expressed between proband-sib pairs (nominal p < 0.01) after controlling for age, sex, and family effects. Probands and siblings were distinguished into two groups by cluster analysis with these genes. Overall, unaffected siblings were equally distant from the centroid of probands and from that of unrelated controls with the differentially expressed genes. Interestingly, five of 20 siblings had gene expression profiles that were more similar to unrelated controls than to their matched probands. In summary, we found a set of genes that distinguished probands from the unaffected siblings, and a subgroup of unaffected siblings who were more similar to probands. The pathways that characterized probands compared to siblings using peripheral blood gene expression profiles were the up-regulation of ribosomal, spliceosomal, and mitochondrial pathways, and the down-regulation of neuroreceptor-ligand, immune response and calcium signaling pathways. Further integrative study with structural genetic variations such as de novo mutations, rare variants, and copy number variations would clarify whether these transcriptomic changes are structural or environmental in origin.
Speciation and quantitation of Aroclors in hazardous wastes based on PCB congener data

Abstract Selected chlorobiphenyl congener data were used to accurately estimate the Aroclor content of hazardous wastes. Only 12 chlorobiphenyl congeners are determined nominally, IUPAC Nos. 15, 18, 31, 87, 105, 110, 118, 170, 180, 183, 203 and 206, and from these marker compounds Aroclors 1016, 1254, 1260 and 1268 are estimated. The remaining regulated Aroclor mixtures also are measured by this technique making it suitable for enforcement of existing California and U. S. regulations. An additional 34 chlorobiphenyl congeners are routinely analyzed allowing determination of PCBs in highly weathered and/or treated wastes. Included are the major constituents of the commercial Aroclors and the predominant congeners in the environment. The sum of PCB congener concentrations, “s-PCB”, is generally about 70% of the total Aroclor content. The use of capillary column separations and data reduction procedures described has a number of advantages over packed column GC procedures: 1) data interpretation does not require analyst judgement and can be automated; 2) the techique makes full use of the separation power of capillary columns to minimize interference by pesticides and other sample components; and 3) the technique accurately measures PCBs in samples with more than one Aroclor. Application of this technique to the determination of Aroclors in auto shredder waste is described and results compared to a packed-column procedure, U. S. EPA method 8080.
Improving clinical trial design for hepatocellular carcinoma treatments

Despite its place as the third leading cause of cancer deaths worldwide, there are currently no approved chemotherapeutic agents, devices or techniques to treat hepatocellular carcinoma. Importantly, there have been no phase III studies demonstrating survival benefit, nor any randomized studies of treatment except for transarterial chemoembolization and most recently sorafenib. The importance of well-designed clinical trials of agents to treat HCC has never been greater. However, general clinical study design issues, combined with HCC-specific issues pose significant challenges in structuring such studies. HCC-related challenges include the heterogeneity of this cancer and the fact that it is frequently accompanied by significant comorbidities at diagnosis, such as active hepatitis B or C virus replication, substantial past or on-going alcohol use, and cirrhosis, itself often a fatal disease. The recently published comparison of a newer treatment, nolatrexed to doxorubicin, and comments about this study’s initial HCC diagnostic criteria, staging system, comparator therapy and choice of endpoints have provided a platform to discuss the challenges unique to the design of HCC clinical trials. The difficulty in accurately framing study results obtained from the constantly changing HCC clinical landscape and approaches to meet these challenges will be reviewed.
Ein neuartiges pH‐empfindliches MRI‐Kontrastmittel

Ein vierfach substituiertes Derivat von 1,4,7,10-Tetraazacyclododecan mit koordinierenden Amidgruppen und seitlichen, nichtkoordinierenden Phosphonatgruppen bildet einen Komplex (siehe Struktur) mit Gadolinium(III), der ein langsam austauschendes Innenspharenwassermolekul enthalt (τM=21 μs). Die 20-MHz-Wasserprotonenrelaxivitat des Komplexes stellte sich als stark pH-abhangig heraus. Die Protonierung der nichtkoordinierenden Phosphonatgruppen scheint den prototropen Austausch der gebundenen Wasserprotonen zu katalysieren und dadurch die Grundlage fur einen erhohten Wasserkontrast in der Kernresonanz-Bildgebung unterhalb von pH 7 zu bilden.
An improved face recognition technique based on modular PCA approach

A face recognition algorithm based on modular PCA approach is presented in this paper. The proposed algorithm when compared with conventional PCA algorithm has an improved recognition rate for face images with large variations in lighting direction and facial expression. In the proposed technique, the face images are divided into smaller sub-images and the PCA approach is applied to each of these sub-images. Since some of the local facial features of an individual do not vary even when the pose, lighting direction and facial expression vary, we expect the proposed method to be able to cope with these variations. The accuracy of the conventional PCA method and modular PCA method are evaluated under the conditions of varying expression, illumination and pose using standard face databases.
The effects of DL-p-chlorophenylalanine on learned helplessness in the rat.

Experiment I investigated the replicability of the learned helplessness effect. For 1 hr, one group of Long—Evans hooded rats was exposed to a series of inescapable 4.0-mA electric shocks in a restraining tube. Control subjects were simply restrained in the tube. Twenty-four hours later, all animals received 20 trials of shock—escape in a two-way shuttle-box. Animals which received prior inescapable shock were significantly slower in escaping from shock than were controls, replicating the learned helplessness effect. Experiment II examined the effect of p -chlorophenylalanine-induced depletion of brain serotonin (5-HT) levels on the learned helplessness effect. Thirty-two rats were randomly assigned to treatment conditions in a 2 × 2 factorial design: inescapable shock versus no-shock pretreatment and drug plus vehicle versus vehicle. Forty-eight hours after pretreatment with drug plus vehicle or vehicle, animals received inescapable shock or no-shock pretreatment and were tested 24 hr later for shock—escape in a two-way shuttle-box. PCPA pretreatment increased the subject's reactivity to shock but had no effect upon the learned helplessness phenomenon.
Clinical implications of cancer self-seeding

Most metastatic cancers are incurable--a fact that underscores the limitations of our existing paradigms for understanding metastasis. In this Review, we use breast cancer to explore many of the enigmas revealed by these existing paradigms. Traditionally, metastatic models describe metastasis as a unidirectional process, whereby cancer cells leave a primary tumor and unidirectionally seed metastasis in regional lymph nodes or distant sites. By contrast, recent data indicate that metastasis is a multidirectional process whereby cancer cells can seed distant sites as well as the primary tumor itself. This later process, known as 'self-seeding,' has been validated in diverse experimental models. Here, we show that the self-seeding model may answer many of the mysteries inherent to cancer metastasis. Indeed, reframing our understanding of metastasis within the self-seeding model offers new opportunities for prevention and cure of metastatic cancer.
The formation of R-prime deletion mutants and the identification of the symbiotic genes in Rhizobium fredii strain USDA191.

R-prime plasmids were formed between the plasmid of Rhizobium fredii strain USDA191 containing nodulation and nitrogen-fixation genes, pRjaUSDA191c, and pRL180, and RP1 derivative. R. fredii USDA191 contains four HindIII fragments that hybridize with an 8.7 kb EcoRI fragment that contains nodulation genes from R. meliloti. These four fragments are on pRjaUSDA191c and are 15.5 kb, 12.5 kb, 6.8 kb, and 5.2 kb in size. A series of R-primes generated in E. coli of pRjaUSDA191c were transferred into a Nod- Nif- derivative of strain USDA191 to determine which nodulation region is necessary for nodule formation. Transconjugants containing the 12.5 kb and the 6.8 kb HindIII fragments on segments of pRjaUSDA191c produced nodules on soybean plants. However, transconjugants containing the 12.5 kb HindIII fragment alone were unable to form nodules, suggesting that the 6.8 kb HindIII fragment or the 6.8 kb and the 12.5 kb HindIII fragments together were needed for nodule formation. The 6.8 kb HindIII fragment was subcloned into the vector pVK102 and transferred into transconjugants containing no sequences homologous to R. meliloti nodulation DNA or to transconjugants containing only the 12.5 kb HindIII fragment. Nodules were formed on soybeans only when both the 12.5 kb and the 6.8 kb HindIII fragments were present in R. frediistrain USDA191.
How Bandwidth Selection Algorithms Impact Exploratory Data Analysis Using Kernel Density Estimation

Exploratory data analysis (EDA) can reveal important features of underlying distributions, and these features often have an impact on inferences and conclusions drawn from data. Graphical analysis is central to EDA, and graphical representations of distributions often benefit from smoothing. A viable method of estimating and graphing the underlying density in EDA is kernel density estimation (KDE). This article provides an introduction to KDE and examines alternative methods for specifying the smoothing bandwidth in terms of their ability to recover the true density. We also illustrate the comparison and use of KDE methods with 2 empirical examples. Simulations were carried out in which we compared 8 bandwidth selection methods (Sheather-Jones plug-in [SJDP], normal rule of thumb, Silverman's rule of thumb, least squares cross-validation, biased cross-validation, and 3 adaptive kernel estimators) using 5 true density shapes (standard normal, positively skewed, bimodal, skewed bimodal, and standard lognormal) and 9 sample sizes (15, 25, 50, 75, 100, 250, 500, 1,000, 2,000). Results indicate that, overall, SJDP outperformed all methods. However, for smaller sample sizes (25 to 100) either biased cross-validation or Silverman's rule of thumb was recommended, and for larger sample sizes the adaptive kernel estimator with SJDP was recommended. Information is provided about implementing the recommendations in the R computing language.
Treatment of Herpes Simplex Virus Infections in Pediatric Patients: Current Status and Future Needs

Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) are members of the Herpesviridae family and are characterized by their ability to establish latency after primary infection and subsequently reactivate. HSV infections in the neonatal and pediatric populations range from uncomplicated mucocutaneous diseases to severe, life-threatening infections involving the central nervous system (CNS). The antiviral agent acyclovir has significantly improved treatment outcomes of HSV infections, including the frequency of mucocutaneous recurrences and mortality associated with CNS and disseminated infections.
Degree Conditions for H-Linked Digraphs

Given a (multi)digraph H, a digraph D is H-linked if every injective function ι:V(H) → V(D) can be extended to an H-subdivision. In this paper, we give sharp degree conditions that ensure a sufficiently large digraph D is H-linked for arbitrary H. The notion of an H-linked digraph extends the classes of m-linked, m-ordered and strongly m-connected digraphs.First, we give sharp minimum semi-degree conditions for H-linkedness, extending results of Kuhn and Osthus on m-linked and m-ordered digraphs. It is known that the minimum degree threshold for an undirected graph to be H-linked depends on a partition of the (undirected) graph H into three parts. Here, we show that the corresponding semi-degree threshold for H-linked digraphs depends on a partition of H into as many as nine parts.We also determine sharp Ore–Woodall-type degree-sum conditions ensuring that a digraph D is H-linked for general H. As a corollary, we obtain (previously undetermined) sharp degree-sum conditions for m-linked and m-ordered digraphs.
Endoscopic endonasal transsphenoidal surgery: implementation of an operative and perioperative checklist

Endoscopic endonasal surgery relies heavily on specialized operative instrumentation and optimization of endocrinological and other critical adjunctive intraoperative factors. Several studies and worldwide initiatives have previously established that intraoperative and perioperative surgical checklists can minimize the incidence of and prevent adverse events. The aim of this article was to outline some of the most common considerations in the perioperative and intraoperative preparation for endoscopic endonasal transsphenoidal surgery. The authors implemented and prospectively evaluated a customized checklist at their institution in 25 endoscopic endonasal operations for a variety of sellar and skull base pathological entities. Although no major errors were detected, near misses pertaining primarily to missing components of surgical equipment or instruments were identified in 9 cases (36%). The considerations in the checklist provided in this article can serve as a basic template for further customization...
Leadership in a women's prison

Abstract The process of social interaction was studied in a southeastern correctional institution for women to determine how patterns of interaction were established, how leaders emerged, and what sociological and criminological characteristics the leaders displayed. The study was based on field observations, interviews with the inmates, and examination of the institutional case records. The women identified as leaders had characteristics similar to those of men found to be leaders in other prison studies; that is, they were similar to other prisoners in background but were criminologically more experienced. The women also displayed aggressive behavior generally considered by society to be masculine and had been convicted of crimes more typical of males than females.
Role of Replication Protein A in Double Holliday Junction Dissolution Mediated by the BLM-Topo IIIα-RMI1-RMI2 Protein Complex

The conserved BTR complex, composed of the Bloom's syndrome helicase (BLM), topoisomerase IIIα, RMI1, and RMI2, regulates homologous recombination in favor of non-crossover formation via the dissolution of the double Holliday Junction (dHJ). Here we show enhancement of the BTR-mediated dHJ dissolution reaction by the heterotrimeric single-stranded DNA binding protein replication protein A (RPA). Our results suggest that RPA acts by sequestering a single-stranded DNA intermediate during dHJ dissolution. We provide evidence that RPA physically interacts with RMI1. The RPA interaction domain in RMI1 has been mapped, and RMI1 mutants impaired for RPA interaction have been generated. Examination of these mutants ascertains the significance of the RMI1-RPA interaction in dHJ dissolution. Our results thus implicate RPA as a cofactor of the BTR complex in dHJ dissolution.
"Ninja Looting" for instructional design: the design challenges of creating a game-based learning environment

Computer and video games have become an increasingly prevalent form of entertainment. While the primary purpose of games is entertainment, the underlying design employs a variety of strategies and techniques which require players to analyze, synthesize, and to use critical thinking skills. Ironically, these are also many of the same types of critical thinking skills educators and instructional designers attempt to foster when creating educational materials and media. The purpose of this paper is to present an overview of a 3D game-based learning environment and to highlight some of the issues that arose during the design, development, and production. Specifically, this paper presents (a) game design elements which can be appropriated (looted) from game design, (b) cognitive research that supports the integration of the elements for instructional design, (c) a discussion of challenges encountered while creating a 3D game-based learning environment with limited resources, and (d) various low-cost and free resources (to avoid ninja looting).