cssi/SciSciGPT-SciSciNet huggingface dataset:
Family Structure and the Reproduction of Poverty

Recent analysts have argued that the female-headed family is responsible for the growth of an "underclass" in America. This study uses longitudinal data taken from the Michigan Panel Study of Income Dynamics to address the questions whether and why offspring in female-headed households are more likely to experience persistent poverty in adulthood. Four hypotheses regarding the effect of a father's absence are tested: the "no-effects" hypothesis, the "economic-deprivation" hypothesis, the "father-absence" hypothesis, and the "family-stress" hypothesis. Separate analyses are presented for blacks and whites. The findings indicate that growing up in a female-headed family increases the risk of poverty, but not because of father absence per se. Among whites, economic deprivation and the stress associated with recent family disruption account for nearly all the negative effects of family structure on offsprings' attainment, whereas among blacks the results are more mixed. During the past few years, researchers and policymakers alike have expressed a growing concern over the instability of the American family and the disorganization of community life. Concern for the family has focused on such issues as the increase in divorce, the rise in illegitimate births, and the subsequent growth of female-headed families. Evidence of broader disorganization is found in high levels of crime and drug abuse, in unemployment among large segments of minority youth, and more generally in what is characterized as the emergence of an "underclass" in America (Auletta 1981).
Effect of a fungicide and spray adjuvant on queen-rearing success in honey bees (Hymenoptera: Apidae).

Commercial producers of honey bee queens (Apis mellifera L.) have reported unexplained loss of immature queens during the larval or pupal stage. Many affected queen-rearing operations are situated among the almond orchards of California and report these losses in weeks after almond trees bloom. Almond flowers are a rich foraging resource for bees, but are often treated with fungicides, insecticides, and spray adjuvants during bloom. Anecdotal reports by queen producers associate problems in queen development with application of the fungicide Pristine (boscalid and pyraclostrobin) and spray adjuvants that are tank-mixed with it. To test the effect of these compounds on queen development, a new bioassay was developed in which queens are reared in closed swarm boxes for 4 d, until capping, with nurse bees fed exclusively on artificially contaminated pollen. Pollen was treated with four concentrations of formulated Pristine (0.4, 4,40, and 400 ppm), a spray adjuvant (Break-Thru, 200 ppm), the combination of Pristine and spray adjuvant (400:200 ppm), the insect growth regulator insecticide diflubenzuron (100 ppm) as a positive control, or water as negative control. Chemical analysis revealed that low concentrations of pyraclostrobin (50 ppb), but no boscalid, were detectable in royal jelly secreted by nurse bees feeding on treated pollen. No significant difference in queen development or survival was observed between any of the experimental treatments and the negative control. Only diflubenzuron, the positive control, caused a substantial reduction in survival of immature queens.
The relationship of body mass index distribution to relatively high blood pressure among children and adolescents in Shandong, China

Background: Obesity and hypertension are both common health problems in children and adolescents; several studies have reported that obesity is associated with elevated blood pressure (BP) in both adults and children. However, no studies on the association between body mass index (BMI) distribution and prevalence of relatively high BP among children and adolescents have been reported in China.Aim: The present study examined the relationship of BMI distribution to relatively high BP among children and adolescents in Shandong, China.Subjects and methods: A total of 8568 students (4333 boys and 4235 girls) aged 7–18 years participated in this study. Height, weight and BP of all subjects were measured; BMI of adolescents was calculated from their height and weight. Relatively high BP status was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥ 95th percentile for age and gender. Prevalence of relatively high BP within each BMI percentile category was determined. Comparisons of B...
The photochemical decomposition of diimide in the gas phase

Abstract The photodecomposition of trans -diimide, N 2 H 2 , in its π * ← n + absorption band has been studied in the gas phase at room temperature at wavelengths from 310 to 405 nm, both in the presence and absence of ethylene. Free-radical chain mechanisms are operative in both systems, yielding N 2 + C 2 H 6 in the presence of ethylene and N 2 + H 2 in its absence. It is concluded that the primary photodissociation probably occurs from high vibrational levels of the ground state, reached by rapid intersystem crossing directly from the 1 B g state originally excited. There is no evidence for collisional de-excitation, and dissociation into N 2 H + H or N 2 + 2H probably occurs with a quantum yield close to unity, although some molecular dissociation into N 2 + H 2 cannot be excluded. There is some evidence that N 2 H radicals have appreciable stability in the chain reaction systems at room temperature.
Regional myocardial blood flow in experimental myocardial infarction after pretreatment with aspirin.

The effects of aspirin on myocardial blood flow in an area of ischemia were studied in 12 baboons. In each, a diagonal branch of the left anterior descending coronary artery was ligated. Six of the baboons received aspirin (2 × 600 mg orally, 12 hours and 1 hour before ligation); the other six did not receive aspirin and served as a control group. The extent of myocardial ischemia was delineated with an electrode wire grid on the surface of the anterior left ventricular wall. The maximal area circumscribed by electrodes with 2 mV or more ST segment elevation was compared with the area of reduced myocardial blood flow. Myocardial blood flow was measured with the radioactive microspheres method using strontium-85-labeled carbonized spheres. Two areas of reduced myocardial blood flow were noted, one with severely reduced flow in the center of the myocardial infarct (0 to 49% of noninfarcted myocardium) and another with mild to moderately reduced myocardial blood flow at the border of the myocardial infarct (50 to 90% of noninfarcted myocardium). Myocardial blood flow in the border area (margins of ST elevation area) for the total wall was 85 ± 8% of normal in the aspirin-treated animals and 40 ± 4% in the control group (p
Effects of timber harvest on breeding-site selection by gray treefrogs (Hyla versicolor)

Abstract Despite numerous studies showing reduced amphibian abundance and diversity following habitat modification, little is known about the mechanisms causing these observed patterns. We examined the effects of four experimental forest management treatments on breeding-site selection by gray treefrogs (Hyla versicolor) in Missouri. Our study of four management treatments included a clearcut with high amounts of coarse woody debris (CWD), a clearcut with lower amounts of CWD, a partial timber cut, and an uncut control. We placed five plastic wading pools in each treatment replicated at three sites and found that gray treefrogs laid significantly more eggs in the clearcuts (low-CWD 77,185 eggs; high-CWD 51,990 eggs) than in either the partial (13,553 eggs) or the control (14,068 eggs) treatments. We further examined the importance of distance between breeding sites and mature forest habitat by placing cattle tanks 50 m into clearcuts, 10 m into clearcuts, 10 m into forests, and 50 m into forests. Gray treefrogs oviposited eggs more frequently in the clearcut-edge tanks (17 occasions) than in the clearcut (7), forest (8), or forest-edge (3) tanks, but eggs were not counted. Despite the preference for open canopy breeding sites, oviposition was less in sites located farther from forest edges. Male captures at the tanks indicated that males also preferred clearcut treatments but were not inhibited by the 50 m distance from the forest edge. Although reduced canopy cover over breeding ponds may benefit tadpoles, logging operations should avoid excessively isolating aquatic habitat from forested uplands.
Spectral Reflectance Measurements of a Microcystis Bloom in Upper Klamath Lake, Oregon

ABSTRACT The objective of this study was to measure the in situ spectral reflectance of lake water that contains a bloom of Microcystis, a species of cyanobacteria. Reflectance spectra (350–2,500 nm) of lake water near a boat dock in Upper Klamath Lake, Oregon, were collected with a portable spectrora-diometer on a cloud-free day with sunlight as a source of illumination between 0845 to 0915 hours, Pacific Daylight Time (PDT) on 17 August 2004, at a near-normal angle of observation. The averaged spectrum of the lake water containing the Microcystis bloom exhibits reflectance maxima from 550–590 nm and near 710 nm wavelengths and reflectance minima near 630 nm and 675 nm wavelengths. The reflectance gradually decreases from 810–1,000 nm and has very low reflectance in the 1,000–2,500 nm wavelength region. Our results show that the spectral reflectance of Microcystis at this stage of its bloom remains low for wavelengths longer than 1,000 nm in the near-infrared region of the spectrum. These spectral result...
Excitation of the Hydrogen Atom by Fast Electrons in the Ochkur Approximation

An approximation, recently devised by Ochkur to take into account exchange effect in scattering of fast electrons by an atom, is applied to excitation of the 2 s and 2 p levels of the hydrogen atom. The resulting cross sections are fairly close to the presently most reliable results of a close-coupling treatment.
Feedbacks between fires and wind erosion in heterogeneous arid lands

[1] Shrub encroachment, a widespread phenomenon in arid landscapes, creates “islands of fertility” in degraded systems as wind erosion removes nutrient-rich soil from intercanopy areas and deposits it in nearby shrub-vegetated patches. These islands of fertility generally are considered to be irreversible. Recently, fire has been observed to alter this pattern of resource heterogeneity through the redistribution of nutrients from the fertile islands of burnt shrubs to the surrounding bare soil areas. Despite the recognized relevance of both fires and wind erosion to the structure and function of arid ecosystems, the interactions between these two processes remains poorly understood. This study tests the hypothesis that fire-induced soil hydrophobicity developing in the soils beneath burned shrubs enhances soil erodibility by weakening the interparticle wet-bonding forces. To test this hypothesis, the effects of grass and shrub fires on changes in soil erodibility and on the intensity of fire-induced soil water repellency are compared at both the field and patch scales in heterogeneous arid landscapes. Higher water repellency was observed in conjunction with a stronger decrease in wind erosion threshold velocity around the shrubs than in grass-dominated patches affected by fire, while neither water repellency nor changes in threshold velocity was noticed in the bare soil interspaces. Thus, fires are found to induce soil hydrophobicity and to consequently enhance soil erodibility in shrub-vegetated islands of fertility. These processes create temporally dynamic islands of fertility and contribute to a decrease in resource heterogeneity in aridland ecosystems following fire.
Manipulation of remodeling pathways to enhance the mechanical properties of a tissue engineered blood vessel

There is a current need for a small diameter vascular graft due to the limited supply of autogenous grafts and the failure of synthetic grafts due to thrombosis and/or intimal hyperplasia. The use of living cells and tissues to fabricate a small diameter graft (i.e., tissue engineered blood vessel, TEBV) could be useful given the endothelialization potential and biocompatibility benefits of such a graft. However, while sufficient strength has been attained in a TEBV, coordinate compliance has yet to be fine-tuned. In this study we investigate the effects of biological response modifiers, retinoic acid (RA) and ascorbic acid (AA) on TEBV biomechanics as a function of time and subsequently correlate observed RA/AA induced changes in TEBV mechanics with alterations in smooth muscle cell (SMC) biochemistry. TEBVs were constructed using a fibrillar type I collagen network populated by human aortic smooth muscle cells (AoSMC). Following construction this TEBV was treated with 0.3 mM AA and 0.1 mM RA (concentrations found to induce changes in VSMC phenotype). Ultimate tensile stress (UTS), rate of relaxation (RR) and elastic efficiency (EE) of RA/AA treated and untreated TEBVs were measured following 1, 7, 15, 30, 45, and 60 days of treatment. At corresponding time points, the effect of these treatments on collagen and elastin protein synthesis and mRNA expression was examined. RA/AA treated TEBV strength increased and stiffness decreased compared to controls as a function of time. Relative collagen synthesis in treated TEBVs exceeded control levels by nearly two-fold at 15 and 30 days of incubation. RA/AA treated collagen gene expression followed a similar trend. Relative elastin synthesis was also greater in treated TEBVs as compared to untreated TEBVs at 15 and 30 days of incubation and correspondingly elastin mRNA expression was significantly elevated at 15 days of incubation. These data provide evidence that RA/AA treated TEBVs exhibit mechanical properties which more closely mimic those of a native vessel than their untreated counterparts and that changes in extracellular matrix composition and matrix gene expression in the presence of RA/AA treatment may play an important role in the development of said mechanical properties.
Mindfulness meditation: a primer for rheumatologists

Over the past decade, there has been an increasing interest in meditation as a mind-body approach, given its potential to alleviate emotional distress and promote improved well being in a variety of populations. The overall purpose of this review is to provide the practicing rheumatologist with an overview of mindfulness and how it can be applied to Western medical treatment plans to enhance both the medical and psychological care of patients.
A new species of Eimeria (Apicomplexa: Eimeriidae) from the eastern pipistrelle, Perimyotis subflavus (Chiroptera: Vespertilionidae), in Arkansas.

abstract: During November 2009 and March 2010, 20 adult eastern pipistrelles, Perimyotis ( = Pipistrellus) subflavus, were collected from Polk County, Arkansas, and their feces were examined for coccidian parasites. Two (10%) of the bats were found to be passing oocysts of an undescribed species of Eimeria. Oocysts of Eimeria heidti n. sp. were ovoidal to ellipsoidal, 26.1 × 20.5 µm (23–31 × 18–23 µm), with a bilayered wall, externally rough, internally smooth, and with a shape index of 1.3. Micropyle and oocyst residuum were absent, but a subspherical polar granule was often present. Sporocysts were ovoidal, 13.0 × 8.8 µm (11–15 × 7–13 µm), the shape index was 1.6, a Stieda body was present and sub-Stieda and para-Stieda bodies were absent. A sporocyst residuum consisting of multiple globules dispersed along the perimeter of the sporocyst and between the sporozoites were present, sporozoites were elongate, with a subspherical anterior refractile body and elongate posterior refractile body; a nucleus not...
Rapid HPLC techniques for globin chain synthesis studies.

Globin chain synthesis and α/β ratios were determined in a number of normal subjects, α-thalassemia-2 homozygotes, and β-thalassemia trait using three different techniques. Cation exchange high performance liquid chromatography on a Pharmacia Mono-S, HR 5/5 and reversed phase high performance liquid chromatography on a semi-preparative Vydac C4 column were compared. with the traditional carboxymethylcellulose chromatography.Both high performance liquid chromatography columns give excellent results when 2 mg of hemoglobin was chromatographed in each analysis. By modifying the protocols for column equilibration and gradient shape for preparative Vydac C4 columns, conditions were found yielding excellent resolutions of the labeled globin chains in less than an hour without the need for substantial increase of the flowrate. This method was found to be superior to other methods and may be a suitable alternative for the classical carboxymethylcellulose chromatography. Up to five specimens could easily be analyz...
Rugged Portable Grayscale Optical Correlator for Onboard Automatic Target Recognition Applications

Jet Propulsion Laboratory (JPL) has developed, for the first time, a matchbox-size compact grayscale optical correlator (GOC). In this paper, we will report the recent development of a prototype 512 × 512 GOC utilizing a new miniature ferroelectric liquid crystal spatial light modulator (FLCSLM) with a 7-micron pixel pitch. We will discuss recent progress in the design and packaging technology to achieve a rugged portable GOC module to enable the real-time onboard applications of this miniature GOC. Experimental demonstration of ATR applications using this new GOC will be presented.Copyright © 2003 by ASME
Origin of concatemeric T7 DNA.

The observed concatemers of T7 DNA are consistent with replication schemes resulting in double-helical molecules with 3´ ended tails. Right-ended and left-ended molecules can then join to form dimers which on further replication similarly form larger concatemers.
Estimating Solids-Not-Fat in Herd Milk Using the Plastic Bead Method of Golding

Abstract This study was made to derive and compare equations for estimating solids-not-fat (SNF) in herd milk using the plastic bead method of Golding. Milk was sampled from farm bulk tanks at delivery on alternate days from 64 herds for 1 yr. In all, 1,423 herd samples were analyzed for per cent milk fat, per cent protein (dye-binding), specific gravity (plastic bead method), and per cent total solids by oven-drying. Percentage SNF was estimated by difference (per cent total solids-per cent milk fat). Multiple regression equations were calculated and compared for estimating per cent SNF from density. Single equations were unsatisfactory, because of significant differences between the partial regressions for breeds. The most efficient equations were those including density and per cent milk fat or per cent protein within six milk fat intervals. For these, the standard errors of estimate ranged from 0.11 to 0.14% SNF, and fractions due to regression ranged from 0.60 to 0.77. The average deviations for annual herd averages among herds was 0.04% SNF, with 95% confidence limits of 0.10% SNF. For months the average deviation was 0.05% SNF with 95% confidence limits of 0.14% SNF.
Do growth-retarded premature infants have different rates of perinatal morbidity and mortality than appropriately grown premature infants?

Objective To determine if perinatal morbidity and mortality differ in growth-retarded, small for gestational age (SGA), premature infants and appropriate for gestational age (AGA) infants. Methods All consecutive, singleton, nondiabetic, preterm pregnancies delivered over a 15-year period were analyzed. Infants were categorized as SGA (at or below the tenth percentile) or AGA (11th to the 89th percentiles), then stratified by birth weight and gestational age categories. Perinatal morbidity and mortality were examined. Results We studied 4183 preterm deliveries, 1012 of them SGA and 3171 of them AGA. Overall, we found significantly higher rates of fetal and neonatal death in the SGA group. Stratification by gestational age revealed significantly higher rates of neonatal death for the SGA group compared with the AGA group in each gestational age category. Overall, comparison also revealed significantly higher rates of fetal heart rate abnormality in the SGA group but no difference in neonatal sepsis, birth trauma, cesarean delivery, hyaline membrane disease, or congenital anomalies. Conclusion Growth-retarded premature infants have a significantly higher risk of morbidity and mortality, both before and after delivery, than do appropriately grown infants.
CHARACTERIZATION OF THE MITOCHONDRIAL CYTOCHROME B GENE FROM VENTURIA INAEQUALIS

A new class of agricultural fungicides derived from the group of antifungal strobilurins acts as specific respiration inhibitors by binding to mitochondrial cytochrome b. The cytochrome b gene was cloned and sequenced from the mitochondrial genome of Venturia inaequalis, the causal agent of apple scab. The gene was 10.65 kbp in size and contained seven exons and six introns. The exons encoded a protein of 393 amino acids. Comparison of the deduced amino-acid sequence with cytochrome b proteins from other fungi revealed highest homologies to the respective proteins of Aspergillus nidulans, Podospora anserina and Neurospora crassa. All amino acids of the V. inaequalis cytochrome b at positions altered in mutants of Saccharomyces cerevisiae resistant to strobilurins, and other fungi with reduced sensitivities to strobilurins, were identical to wild-type isolates of several fungi. The cloning and characterization of the V. inaequalis cytochrome b gene is the initial step in the assessment of resistance risks inherent to the strobilurin fungicides.
Effects of Imprisonment upon Authoritarian Attitudes

Samples of prison inmates varying in length of imprisonment from 0 to 6 years were administered an authoritarianism scale. An analysis of the data showed 14 sub-groupings of items, some of which were negatively related to time, others curvilinearly, and others completely unrelated. It was argued that ‘authoritarianism’ is a complex concept composed of more discrete and homogeneous components, some of which may be presumed to be more stable or ‘personality-based’ than others. Possible implications for penology were also mentioned.
A simple micromethod for simultaneous determination of plasma propranolol and 4-hydroxypropranolol.

Abstract A simple micromethod using 1 ml plasma for simultaneous determination of propranolol and 4-hydroxypropranolol is described. This method employs toluene for complete extraction of propranolol and 4-hydroxypropranolol (99%) as free amines from plasma, and acetic acid (0.005 M) in 5% ethylene glycol at pH 3.7 for quantitative re-extraction and maximum fluorescence. The propranolol and 4-hydroxypropranolol are measured fluorometrically at 290/ 358 nm and 320/510 nm. The correlation between-this method and Shand's method for plasma propranolol is excellent ( r = 0.99, n = 53). The precision of the method for propranolol measurement in the range 15–400 ng/ml is good, average C.V. of 3.1% ( n = 20) and with a low, consistant and reproducible (C.V. 1.9%) blank plasma value. The sensitivity of the method for propranolol as measured by fluorescence ratio (standard, 100 ng propranolol/blank) is very high, 17.1 compared to 3.2 of Shand's method. The reproducibility and recovery for 4-hydroxypropranolol added to pooled serum in the range 25–400 ng/ ml is excellent, average C.V. 5.4% and 98% respectively ( n = 20). The minimum detectable amount of propranolol is 2.5 ng/ml and for 4-hydroxypropranolol 15 ng/ml using 1 ml plasma samples. No interference from normal plasma constituents or from commonly prescribed cardiovascular drugs is observed. Peak propranolol levels are reached on an average of 60.5 h after initiation of propranolol therapy in patients, receiving propranolol one time intravenously (0.1 mg/kg), followed by 40, 60 mg and then by 80 mg/6 h. After the peak, propranolol levels remain relatively steady, with a mean C.V. of 14.2%. Plasma propranolol levels vary from patient to patient in the “steady state”. Peak values (1 h post propranolol) average 240 ng/ml (125–621) and trough values (10 min prior to propranolol) average 177 ng/ml (59–550) in 11 patients. However, the 4-hydroxypropranolol to propranolol ratio is relatively stable (0.23 to 0.31) and averages 0.27.
A mechanistic population balance model for transient and steady-state foam flow in Boise sandstone

Foam in porous media is discontinuous on a length scale that overlaps with pore dimensions. This foam-bubble microstructure determines the flow behavior of foam in porous media and, in turn, the flow of gas and liquid. Modeling of foam displacement has been frustrated because empirical extensions of the conventional continuum and Newtonian description of fluids in porous media do not reflect the coupling of foam-bubble microstructure and foam rheology. We report a mechanistic model for foam displacement in porous media that incorporates pore-level mechanisms of foam generation, coalescence, and transport in the transient flow of aqueous foams. A mean-size foam-bubble conservation equation, along with the traditional reservoir/groundwater simulation equations, provides the foundation for our mechanistic foam-displacement simulations. Since foam mobility depends heavily upon its texture, the bubble population balance is both useful and necessary, as the role of foam texture must be incorporated into any model which seeks to predict foam flow accurately. Our model employs capillary-pressure-dependent kinetic expressions for lamellae generation and coalescence, and incorporates trapping of lamellae. Additionally, the effects of surfactant chemical transport are included. All model parameters have clear physical meaning and, consequently, are independent of flow conditions. Thus, for the first time, scale up of foam-flow behavior from laboratory to field dimensions appears possible. The simulation model is verified by comparison with experiment. In situ, transient, and steady aqueous-phase liquid contents are garnered in a 1.3 μm2 Boise sandstone using scanning gamma-ray densitometry. Backpressures exceed 5 MPa, and foam quality ranges from 0.80 to 0.99. Total superficial velocities range from as little as 0.42 to 2.20 m/d. Sequential pressure taps measure flow resistance. Excellent agreement is found between experiment and theory. Further, we find that the bubble population balance is the only current means of describing all flow modes of foam self-consistently.
Double-Gate Strained-Ge Heterostructure Tunneling FET (TFET) With record high drive currents and ≪60mV/dec subthreshold slope

The main challenges for Tunnel FETs are experimentally demonstrating SS<60 mV/dec, high ON currents and solving their ambipolar behavior. We have experimentally demonstrated a Double-Gate, Strained-Ge, Heterostructure Tunneling FET (TFET) exhibiting very high drive currents and SS<60 mV/dec. Due to small bandgap of s-Ge and the electrostatics of the DG structure, record high drive current of 300 uA/um (the highest ever reported experimentally for a TFET) and a subthreshold slope of ~50 mV/dec was observed. In addition, to address the ambipolar problem and examine the scalability of TFETs, we have developed a sophisticated TFET simulator that uses a Quantum transport model, Non-local BTBT, complete Bandstructure (real and complex) information, and includes all transitions (direct and phonon assisted). Using this simulator, we have studied the scalability of three asymmetric DG TFET configurations (underlapped drain, lower drain doping and lateral heterostructure) in terms of their ability to solve the ambipolar behavior and achieve high ON and low OFF currents.
Integrating intimate partner violence content across curricula: Developing a new generation of Nurse Educators

Summary Abuse between intimate partners can take many forms. Prevalence data analyses confirm that intimate partner violence (IPV) is a widespread problem. Meeting the objectives of World Health Organization’s “Global Campaign on Violence Prevention” will involve many organizations and institutions within and beyond the health care community. Educating prospective Nurse Educators about IPV does, however, present challenges, as most nurses lack awareness of IPV as a public health problem, have limited knowledge and erroneous beliefs about IPV, and are inexperienced in caring for survivors of IPV. Thus providing formal education and training in a supportive environment will enhance Nurse Educators’ knowledge and skills about IPV while helping them to examine the benefits and limitations of various pedagogical approaches for teaching this critical content to students. Hence targeting educational efforts at nurses who are pursuing the academic role is an important first step toward raising the collective consciousness of nurses to the point that IPV education becomes an integral component of the nursing curriculum, and competence in caring for IPV survivors becomes the standard rather than the exception.
RlmN and Cfr are Radical SAM Enzymes Involved in Methylation of Ribosomal RNA

Posttranscriptional modifications of ribosomal RNA (rRNA) nucleotides are a common mechanism of modulating the ribosome's function and conferring bacterial resistance to ribosome-targeting antibiotics. One such modification is methylation of an adenosine nucleotide within the peptidyl transferase center of the ribosome mediated by the endogenous methyltransferase RlmN and its evolutionarily related resistance enzyme Cfr. These methyltransferases catalyze methyl transfer to aromatic carbon atoms of the adenosine within a complex 23S rRNA substrate to form the 2,8-dimethylated product. RlmN and Cfr are members of the Radical SAM superfamily and contain the characteristic cysteine-rich CX(3)CX(2)C motif. We demonstrate that both enzymes are capable of accommodating the requisite [4Fe-4S] cluster. S-Adenosylmethionine (SAM) is both the methyl donor and the source of a 5'-deoxyadenosyl radical, which activates the substrate for methylation. Detailed analyses of the rRNA requirements show that the enzymes can utilize protein-free 23S rRNA as a substrate, but not the fully assembled large ribosomal subunit, suggesting that the methylations take place during the assembly of the ribosome. The key recognition elements in the 23S rRNA are helices 90-92 and the adjacent single stranded RNA that encompasses A2503. To our knowledge, this study represents the first in vitro description of a methyl transfer catalyzed by a member of the Radical SAM superfamily, and it expands the catalytic repertoire of this diverse enzyme class. Furthermore, by providing information on both the timing of methylation and its substrate requirements, our findings have important implications for the functional consequences of Cfr-mediated modification of rRNA in the acquisition of antibiotic resistance.
Processing properties of polypropylene with a minor addition of silicone oil

Processing-related properties of a polypropylene (PP)/ silicone oil blend were investigated. It was found that an addition of a small amount (~2 wt%) of silicone oil, a low molecular weight linear poly(dimethyl siloxane) (PDMS), drastically changed the rheological properties of PP. The PDMS seemed to work both as an internal lubricant and an external lubricant in the blend system. In particular, the apparent viscosity of the blend in capillary rheometry was approximately 10 times lower than that of virgin PP. The local minima in the viscosity versus shear rate curve in capillary rheometry and the gap-dependency of viscosity in parallel-plate rheometry implied the existence of a slip wall condition, caused by the formation of a thin lubricant layer at die walls. Thermal analyses and mechanical tests showed that the thermal and mechanical properties of the blend were nearly unaffected by the minor addition of silicone oil. The blend was tested in a profile extrusion process, and a significant reduction in die swell and profile distortion was achieved. The jet stretchability or spinnability in fiber spinning was also greatly improved with the minor addition of silicone oil. POLYM. ENG. SCI., 50:1340-1349, 2010. © 2010 Society of Plastics Engineers.
The frequency and pressure dependence of the absorption of pulsed CO2 laser radiation by phosphine

Abstract Absorption of IR radiation from a high power CO2 laser by phosphine has been studied. At a constant pressure of phosphine, the fraction of energy absorbed is characteristic of the laser frequency. For a fixed laser frequency and constant incident intensity the pressure dependence of the optical density can be approximated by an empirically modified Beer-Lambert law. The effect of an added non-absorbing gas on the absorption coefficient of phosphine can be expressed simply by the addition of an appropriate term to the modified Beer-Lambert equation. Both dependences represent a phenomenological description of the effect of collisions on the IR multiphoton absorption process.
A roentgenographic method for rapid evaluation of x-ray machines.

Abstract A new method in which Polaroid type 52 Land films are used for the evaluation of x-ray machines is presented. The black and white print, which is developed in ten seconds, demonstrates the adequacy of collimation, the aiming of the central beam, and any scattering or leakage of radiation in the anterior direction. By comparison with standard exposures, an accurate estimate can be made of the roentgen output of the x-ray machine. The method is very rapid and provides a more than adequate substitute for the fluorescent screen and radiation recorders now in use for direct evaluations of x-ray machines.
ALGORITHMIC CONSTRUCTION OF KIRBY DIAGRAMS FOR BRANCHED COVERS

We present an algorithm that converts any description of a 3-manifold as a finite-sheeted cover of the 3-sphere, branched over some knot or knotted graph, into a Kirby diagram for that manifold, thus resolving the problem posed in [4].
Comparison of the Effects of β‐Adrenergic Agents on Pineal Serotonin N‐Acetyltransferase Activity and Melatonin Content in Two Species of Hamsters

The nighttime rise in pineal melatonin levels can be blocked by administration of the beta-adrenergic receptor antagonist, propranolol, in both Syrian hamsters and rats. Although the administration of beta-adrenergic receptor agonists such as norepinephrine or isoproterenol stimulates pineal melatonin production in the rat, these drugs are without apparent effect on indole production in the Syrian hamster. To determine whether this lack of stimulatory effect in the Syrian hamster is characteristic of this species, a comparison of the effects of norepinephrine and isoproterenol on pineal serotonin N-acetyltransferase activity and melatonin content was conducted. In contrast to their lack of effect in the Syrian hamster, norepinephrine and isoproterenol stimulated pineal serotonin N-acetyltransferase activity and melatonin content in the Djungarian hamster. Hourly injection of norepinephrine during a continuation of light into the normal dark period stimulated increases in the activity of serotonin N-acetyltransferase and melatonin content in the Djungarian hamster but was without effect on these pineal parameters in the Syrian hamster.
Grazing Effects on Yield and Quality of Hard Red and Hard White Winter Wheat

Six hard red (2137, Jagalene, Jagger, OK101, Stanton, and Thunderbolt) and six hard white (Burchett, Lakin, NuFrontier, NuHills, NuHorizon, and Trego) winter wheat (Triticum aestivum L.) varieties were evaluated for grain yield and quality in southwestern Kansas in 2004 and 2005. Cattle commonly graze wheat in this region from late November to mid March in a dual-purpose system. The experimental design was a randomized complete block with split-plot treatment arrangement. Main plots were grazed or ungrazed, and subplot treatments were wheat varieties. Yield was not affected by color. Yield was reduced 23% when grazed beyond wheat jointing. NuHorizon yielded less when grazed. Test weight was 4 kg m ―3 greater among red varieties in 2004 and 4 kg m ―3 greater among white varieties in 2005. Grazing did not affect test weight. Color and grazing did not affect protein concentration. White varieties sprouted more than red varieties, but Burchett sprouted less than Stanton. Grazing did not affect sprouting. Kernel diameter was 0.1 mm greater among red than white varieties. Grazing reduced kernel diameter 0.1 mm in 2004. Kernel hardness was 4% greater among white than red varieties. Grazing increased kernel hardness 3% in 2005. Seed weight was 5% greater among red than white varieties. Grazing reduced seed weight 4%. Both red and white wheat can be used in a dual-purpose system with no substantial affects on yield or quality. Producers should select varieties on the basis of their system and environment because certain varieties responded better to grazing and environmental conditions than others.
Oceanography from space

Spaceborne Synthetic Aperture Radar for Oceanography.. Edited by Robert C. Beal, Pat S. DeLeonibus and Isadore Katz. Pp.216. ISBN 0-8018-2668-3. (The Johns Hopkins University Press: 1981.) $29.25, £17.
Teachers' Perceptions of Assertive and Aggressive Behavior at School: A Discriminant Analysis

Summary.-To clarify empirically the definitions of aggressive and assertive behavior the investigators obtained samples of aggressive, assertive, and non-assertive-non-aggressive students from 10 public high school teachers who made nominations to the three criterion groups (ns = 30) and completed individual adjective checklists. For each nominee, data were collected on four variables: impulsiviry, dependence, hostility, and grade-point average. A discriminant analysis of the data yielded two significant discriminant functions which differentiated the behavioral groups Further statistical analyses showed that differences existed in the rank~ngs of the variables among the assertive, aggressive, and non-assertive-non-aggtess~ve subjects. A discussion of these findings and the implications of using teachers' perceptions as a research tool follows. The primary purpose of this study was an empirical validation of teachers' perceptions of assertiveness and aggressiveness in the classroom. The question we raise is whether teachers provided with descrqtions rather than with labels of assertive, aggressive, and non-assertive-non-aggressive behavior can place students differentially into one of these groups. For the most part earlier investigations of assertiveness and aggressiveness have a clinical focus, e.g., assertiveness or behavior modifications programs aimed at reducing aggressiveness in various populations. Rich and Schroeder (1976) and DeGiovanni and Epstein (1978) in their review articles note the failure of clinical research to distinguish clearly between assertive and aggressive behavior. DeGiovanni and Epstein also point out the paucity of empirical data directed to the difficult task of clarifying the meanings of these two concepts. Since the terms aggressiveness and assertiveness are too often used interchangeably in the literature, at the outset we adopted definitions that in our judgment are not ambiguous. Alberti and Simmons (1970) and Kirchner, et a1. (1979) define assertiveness as behavior performed in the light of personal interests and rights, executed without undue anxiety or the intent of destroying the rights of others. Albetti and Simmons (1970) view aggressiveness as behavior resulting in injury to another person, an animal, or an object. The descriptions of aggressive and assertive behavior developed for the teachers in this study were based on the preceding distinctions. We therefore
Computerized decision support system improves fluid resuscitation following severe burns: An original study

Objective Several formulas have been developed to guide resuscitation in severely burned patients during the initial 48 hrs after injury. These approaches require manual titration of fluid that may result in human error during this process and lead to suboptimal outcomes. The goal of this study was to analyze the efficacy of a computerized open-loop decision support system for burn resuscitation compared to historical controls. Design Fluid infusion rates and urinary output from 39 severely burned patients with >20% total body surface area burns were recorded upon admission (Model group). A fluid-response model based on these data was developed and incorporated into a computerized open-loop algorithm and computer decision support system. The computer decision support system was used to resuscitate 32 subsequent patients with severe burns (computer decision support system group) and compared with the Model group. Setting Burn intensive care unit of a metropolitan Level 1 Trauma center. Patients Acute burn patients with >20% total body surface area requiring active fluid resuscitation during the initial 24 to 48 hours after burn. Measurements and main results We found no significant difference between the Model and computer decision support system groups in age, total body surface area, or injury mechanism. Total crystalloid volume during the first 48 hrs post burn, total crystalloid intensive care unit volume, and initial 24-hr crystalloid intensive care unit volume were all lower in the computer decision support system group. Infused volume per kilogram body weight (mL/kg) and per percentage burn (mL/kg/total body surface area) were also lower for the computer decision support system group. The number of patients who met hourly urinary output goals was higher in the computer decision support system group. Conclusions Implementation of a computer decision support system for burn resuscitation in the intensive care unit resulted in improved fluid management of severely burned patients. All measures of crystalloid fluid volume were reduced while patients were maintained within urinary output targets a higher percentage of the time. The addition of computer decision support system technology improved patient care.
A Numerical Approach for Analyzing Three-Dimensional Steady-State Rolling Contact Including Creep Using a Fast Semi-Analytical Method

This article presents a new rolling contact solver using a semi-analytical method (SAM) to analyze three-dimensional steady-state rolling contacts, including the effects of creep. This new solver includes both the normal and tangential contact issues for the pressure and shear tractions, respectively. The accuracy and efficiency of the present method are demonstrated by comparison to existing analytical and numerical solutions. Rolling contact problems for a smooth infinite roller pressed against a half space with either a single asperity or a sinusoidal wave are investigated. The results show the complexity of pressure and shear traction. Asperities produce higher localized pressures, which demand larger local shear tractions to produce slip in such regions. Stick regions are also observed at the trailing edge of the contact.
Variability of Moisture in the Upper Troposphere As Inferred from TOVS Satellite Observations and the ECMWF Model Analyses in 1989

Large-scale variability of moisture in the upper troposphere is examined using TIROS (Television Infrared Observation Satellite) Operational Vertical Sounder (TOVS) satellite observations and European Centre for Medium-Range Weather Forecasts (ECMWF) model analyses from 1989 in the latitude band from 40 deg N to 40 S. To compare these dissimilar datasets, upwelling radiances were computed for the 6-7 micrometer water vapor band from the ECMWF temperature and moisture analyses, and these computed radiances were compared to the corresponding TOVS satellite observations. The ECMWF-based radiances reproduce the general locations and seasonal cycle of the TOVS-observed moisture features, particularly after an improved convective parameterization scheme was adopted by ECMWF in May 1989. However, the ECMWF analysis scheme still results in much milder lateral moisture gradients and seasonal contrasts than indicated by the TOVS observations. Seasonally, the upper troposphere in each hemisphere dries in winter and moistens in summer, but there are regions in each hemisphere that run counter to this seasonal trend, apparently depending on continental- and monsoon-scale dynamics. Dynamically, the TOVS-observed regions of significant subtropical dryness are correlated with persistent subsidence indicated by ECMWF 300-mb vertical velocity analyses. The TOVS radiance observations indicate large variations in space and time of the upper-tropospheric moisture field, which are not fully captured by the ECMWF analyses.
The effect of labour costs, holding costs, and uncertainty in demand on pull inventory control policies

Multi-plant coordination has been complicated by the recent trend towards globalization. In this paper, a model that simultaneously establishes values for various aggregate parameters such as target inventories and also identifies characteristics of the best pull control strategy is applied to a specific global manufacturing network. A simulation study is done to explore the effect of labour costs and holding costs on target inventories, actual inventories and pull control strategy. A second simulation experiment is used to examine the effect of variability in demand on these same decision variables. Implications for management are discussed and suggestions for further work are presented.
Controls by saturation state on etch pit formation during calcite dissolution

Dissolution experiments were conducted on {1014} cleavage faces of calcite at various under-saturations to determine how the saturation state controls etch pit formation. Experimental observations were made by using in situ fluid cell Atomic Force Microscopy. Three dissolution modes were observed. When the saturation index Ω > 0.541, no etch pit formation was seen and dissolution primarily occurred at existing steps. When Ω decreased to Ωc = 0.541–0.410, the first visible pits appeared and continuous reduction in saturation state slowly increased the pit density on terraces while dissolution simultaneously proceeded at step edges. Finally, when the saturation state fell below Ωmax = ∼0.007, a precipitous increase in pit density took place that sharply contrasted to the ordered fashion of pit formation observed at saturation conditions above this level. These observations are interpreted to be two-dimensional and unassisted pit formation at Ω 0.541. The values of Ωc are in good agreement with the dislocation theory's predicted critical under-saturations for pit formation at line dislocations. The occurrence of Ωmax is not directly predicted but is a logical consequence of dissolution thermodynamics. These findings suggest that (1) dissolution near and far from equilibrium (i.e., Ω > Ωc, Ω < Ωmax) is not controlled by dislocations, therefore (2) dislocation density should significantly impact dissolution rate only in the saturation range of Ωmax < Ω < Ωc; (3) dissolution kinetics and chemical affinity of dissolution reactions should have a non-linear relationship: at sufficiently close to equilibrium, when dislocations cannot open up to form etch pits, the dissolution kinetics will be limited by the number of existing steps; at far from equilibrium, when pits are able to form in defect-free regions, the dissolution rate will be capped by the maximum number of achievable steps. These findings may provide explanations for several well-observed geochemical relationships, including the weak dependence of dissolution rate upon dislocation density in distilled water and the ‘plateau’ behavior of dissolution kinetics both near and far from equilibrium. The explosive occurrence of unassisted pit nucleation at Ω ∼ Ωmax is not predicted by the current dissolution rate equations. This suggests that an accurate ‘general’ rate law describing universal dissolution processes has yet to be developed.
Pharmacological selectivity of CTAP in a warm water tail-withdrawal antinociception assay in rats

Rationale To facilitate in vivo characterization of the mu antagonist Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 (CTAP), the present study characterized CTAP selectivity in vivo.
A multivariate, osteological approach to Towa culture history

Eleven cranial measurements on 14 archeological populations from the American Southwest support the archeologically derived reconstruction of Towa population movements. The supposed (linguistic) relationship between Pecos and the Towa speaking villages is questioned.