cssi/SciSciGPT-SciSciNet huggingface dataset:
Uptake and distribution of fullerenes in human mast cells

Fullerenes are carbon cages of variable size that can be derivatized with various side chain moieties resulting in compounds that are being developed into nanomedicines. Although fullerene use in several preclinical in vitro and in vivo models of disease has demonstrated their potential as diagnostic and therapeutic agents, little is known about how they enter cells, what organelles they target, and the time course for their cellular deposition. Fullerenes (C70) that have already been shown to be potent inhibitors of mast cell (MC)–mediated allergic inflammation were conjugated with Texas red (TR) and used in conjunction with confocal microscopy to determine mechanisms of uptake, the organelle localization, and the duration they can be detected in situ. We show that C70-TR are nonspecifically endocytosed into MCs, where they are shuttled throughout the cytoplasm, lysosomes, mitochondria, and into endoplasmic reticulum at different times. No nuclear or secretory granule localization was observed. The C70-TR remained detectable within cells at 1 week. These studies show that MCs endocytose fullerenes, where they are shuttled to organelles involved with calcium and reactive oxygen species production, which may explain their efficacy as cellular inhibitors.
Aflatoxin B1—Effects on rainbow trout liver chromatin☆

Abstract Injection of 400 μg/kg doses of aflatoxin B 1 into the Virginia strain of rainbow trout resulted in quantitative changes in the protein/DNA ratio of liver chromatin. Ammoniacal-silver staining indicated a 41 per cent loss of chromatin stainability. A 65 per cent total loss of histone and acidic proteins, relative to DNA, was observed by direct measurement of extracted and fractionated chromatin. Losses of chromatin protein were restored within 48 hr after injection.
Sodium-hydrogen exchange inhibition attenuates in vivo porcine myocardial stunning

Abstract Background Inhibition of the sodium-hydrogen exchanger isoform 1 with HOE-642 (cariporide) has been shown to protect against ischemia-reperfusion injury and to decrease myocardial cell death in numerous animal preparations; however the effects of cariporide in stunned myocardium are not as well understood. We sought to determine whether cariporide attenuated myocardial stunning in vivo. Methods Open chest anesthetized pigs (22–33 kg) were subjected to 15 min of left anterior descending coronary artery (LAD) occlusion followed by 3 h of reperfusion. Regional ventricular function was assessed by segment shortening. Contractility was measured by stroke work and by load-insensitive preload recruitable stroke work and preload recruitable stroke work area. Vehicle or HOE-642 (1 mg/kg, IV) was administered 10 min before LAD occlusion. Results Cariporide treatment significantly improved postischemic segment shortening, stroke work, preload recruitable stroke work, and preload recruitable stroke work area and had no systemic hemodynamic effects. After 3 h of reperfusion, control animals recovered 33% ± 4% and 33% ± 3% of preischemic LAD segment shortening and preload recruitable stroke work area values, respectively, whereas animals treated with HOE-642 recovered 59% ± 6% and 57% ± 6%, respectively ( p Conclusions Sodium–hydrogen exchange inhibition can attenuate postischemic myocardial stunning in addition to its well-described anti-infarct properties. Inhibition of the sodium–hydrogen exchanger may be beneficial in patients susceptible to postischemic myocardial dysfunction associated with cardiac surgery.
Properties of an ideal PET perfusion tracer: New PET tracer cases and data

An ideal positron emission tomography (PET) tracer should be highly extractable by the myocardium and able to provide high-resolution images, should enable quantification of absolute myocardial blood flow (MBF), should be compatible with both pharmacologically induced and exercise-induced stress imaging, and should not require an on-site cyclotron. The PET radionuclides nitrogen-13 ammonia and oxygen-15 water require an on-site cyclotron. Rubidium-82 may be available locally due to the generator source, but greater utilization is limited because of its relatively low myocardial extraction fraction, long positron range, and generator cost. Flurpiridaz F 18, a novel PET tracer in development, has a high-extraction fraction, short positron range, and relatively long half-life (as compared to currently available tracers), and may be produced at regional cyclotrons. Results of early clinical trials suggest that both pharmacologically and exercise-induced stress PET imaging protocols can be completed more rapidly and with lower patient radiation exposure than with single-photon emission computerized tomography (SPECT) tracers. As compared to SPECT images in the same patients, flurpiridaz F 18 PET images showed better defect contrast. Flurpiridaz F 18 is a potentially promising tracer for assessment of myocardial perfusion, measurement of absolute MBF, calculation of coronary flow reserves, and assessment of cardiac function at the peak of the stress response.
Exploring The Stereochemistry Of The Wittig Reaction: The Unexpected Influence Of A Nominal Spectator Ion

Students in the second-semester organic chemistry laboratory perform a Wittig reaction between butylidenetriphenylphosphorane (an ylide) and benzaldehyde and determine the relative percentages of t...
Student Development Among Community College Participants in Study Abroad Programs

For decades, institutions of higher education have provided study abroad opportunities for college students wishing to increase and expand their intellectual and social skills. While many universities around the country have supported successful international exchange and study abroad programs, there is little research on community college study abroad programs and their impact on student development. Therefore, this article examines specific vectors that impact student development before and after study abroad participation in nine community colleges using Chickering's Theory of Student Development and SAS statistical methods.
Esophagitis: A frequent consequence of gastroesophageal reflux in infancy

A control group of infants was evaluated to determine criteria for the diagnosis of histologic esophagitis. Based on our observations, histologic esophagitis was defined as four or more intraepithelial neutrophils or one eosinophil per high power field or both. Esophageal biopsy specimens from 33 consecutive infants younger than 2 years who had been examined for clinically significant gastroesophageal reflux (GER) were reviewed for histologic esophagitis. Endoscopy had been performed in each patient, and 4.1±1.1 (mean±SD) biopsy specimens had been obtained above the distal 20% of the esophagus. Twenty (61%) infants had histologic esophagitis, including 15 with intraepithelial eosinophils alone, one with intraepithelial neutrophils alone, and four with both. Older infants (7 to 24 months) with histologic esophagitis were more likely to have moderate to severe inflammation than were infants younger than 7 months of age (P=0.01). Endoscopic evidence for gross esophagitis was found in six (18%) infants; of these, five had abnormal biopsies, including four with moderate to severe inflammation. Among the 27 infants with a grossly normal esophagus, 14 (52%) had histologic esophagitis, including nine (33%) with moderate to severe inflammation. We conclude that in infants with clinically significant GER: (1) esophagitis is common, (2) histologic esophagitis frequently occurs in the absence of gross endoscopic findings, (3) the likelihood of moderate to severe inflammation increases after 6 months of age, and (4) intraepithelial eosinophils are a sensitive marker for acute inflammation in association with GER.
Synthesis of bromodifluoromethyl phenyl sulfide, sulfoxide and sulfone [1]

Abstract Sodium thiophenoxide reacts with dibromodifluoromethane to give bromodifluoromethyl phenyl sulfide. Peracid oxidation of the sulfide gives the corresponding sulfoxide and sulfone. The formation of the sulfide is suggested to proceed via attack of thiophenoxide on halogen to produce difluorocarbene. Capture of carbene by thiophenoxide followed by a second positive halogen abstraction reaction yields the sulfide, PhSCF2Br. The use of excess sodium thiophenoxide yields difluorobis(thiophenyl)methane, (PhS)2CF2, via a similar mechanistic scheme.
Non-fluorinated tetradentate β-ketoamines as derivatizing ligands for the gas chromatographic analysis of Cu(II), Ni(II) and Pd(II)

The use of a gas chromatographic substrate consisting of Dexsil 300GC on Chromosorb 750 support permits the elution of non-fluorinated tetradentatep'-ketoamine chelates of Cu(II)< Ni(II) and Pd(II) to the nanogram level without degradation. The enhanced volatility of these chelates and the capability for copper and nickel resolution is demonstrated in determinations on noble metal “matte” samples.
Endocrine disruptive compounds and cardio-metabolic risk factors in children

The endocrine disrupting chemicals (EDC) are exogenous chemicals that can disrupt hormonal signaling system. EDCs are ubiquitous in our environment and many EDC are detectable in humans. With the increasing obesity prevalence in children it is imperative to explore the role of EDC as obesogens. This review summarizes recent epidemiological evidence regarding impact of these EDC on weight gain and metabolic outcomes in children. The EDCs include pharmaceuticals, pesticides, industrial by-products, and cigarette smoke. Current evidence suggests a link between early life exposure to some industrial by-products, synthetic hormones and cigarette smoke with weight gain. However, there is inconclusive evidence of an association between exposure to fungicides, dioxin, phytoestrogens, flame retardants, heavy metals and childhood obesity.
Individual differences: incorporating human variation into human factors/ergonomics research and practice

Individual differences in behaviour have traditionally been treated as ‘error variance’ by researchers in experimental psychology and human factors and ergonomics (HF/E) (Karwowski and Cuevas 2003)...
Transdifferentiation of outgrowth cells and cultured epithelial cells from swine trachea

The morphologic and functional properties of explant out-growth cells and epithelial cells isolated from swine trachea epithelium by proteolysis were examined. A mixed population of ciliated, serous, and basal cells, obtained from out-growths, from proteolysis of trachea epithelium, and from unattached explants in organ culture, all yielded cell cultures that were composed almost entirely of mucus-secreting cells. When the cells were grown in primary or secondary culture on a modified collagen matrix in supplemented HAM:DMEM (1:1) medium they expressed a mucus-secreting phenotype with numerous mucus granules at various stages of maturation and incorporated [3H]GlcN and35SO4 into secreted mucin glycoproteins. Results obtained in these studies suggest that extensive transdifferentiation of ciliated and serous cells to mucus-secreting cells occurs after the release and during subsequent attachment and culture. Ciliated cells containing mucus granules were seen in various stages of cilia resorption. Basal cells containing mucus granules were also frequently observed. The number of mucus-secreting cells and the synthesis of mucin glycoproteins increased dramatically with time of attachment and culture, whereas cell proliferation, population doubling time of 72 h, and incorporation of [3H]thymidine into DNA increased much more slowly. The number of mucus-secreting cells correlated closely with the level of secretion of mucin glycoproteins. Taken collectively, these studies help to elucidate the transdifferentiation process, which dramatically increases the number of mucus-secreting cells after disruption and release of epithelial cells from swine tracheobronchial epithelium. A similar mechanism involving disruption of the extracellular matrix may be involved in the stimulation of hypersecretion of mucus and mucin glycoproteins by chemical and infections irritants.
Retropinacol/Cross‐Pinacol Coupling Reactions – A Catalytic Access to 1,2‐Unsymmetrical Diols

A new concept to access unsymmetrical 1,2-diols with high yields is reported. This new methodology is based on a retropinacol/cross-pinacol coupling process. This transformation is characterized by its operational simplicity and very mild reaction conditions.
Vertical fracture of the odontoid process: case report.

FIFTEEN PERCENT OF cervical spine fractures involve the odontoid process. Most odontoid fractures can be classified as Types I through III according to the scheme developed by Anderson and D'Alonzo. We report a case of a vertically oriented fracture through the odontoid process that does not fit into any of these categories. Only two such cases have been described in the literature. Our patient is an 18-year-old man who sustained an axial loading injury to his cervical spine. Plain lateral cervical tomography and computed tomography were performed to characterize the fracture and to evaluate the instability. The patient was placed in a rigid orthosis for 12 weeks, and at 6-month follow-up, he had full range of motion and showed no evidence of abnormal movement, as revealed by flexion-extension studies. This case demonstrates the shortcomings of the current classification system for odontoid fractures and the value of plain tomography and computed tomography in evaluating odontoid fractures.
Radiation trapping in sodium-noble-gas mixtures.

We have studied sodium resonance radiation under conditions of severe radiation trapping in sodium-argon mixtures, and we report measured values of the effective radiative decay rates. The measured values are compared with values calculated from the Holstein theory of radiation trapping in the impact-regime, foreign-gas pressure-broadening limit. The experiment was designed to satisfy all of the validity criteria imposed by the approximations of the Holstein theory, and the experiment and theory are in good agreement. Since the effective radiative decay rate depends upon the collisional line-broadening rate, confirmation of the theory allows such measurements to be used to determine unknown line-broadening constants using only broadband lasers and low resolution monochromaters. We demonstrate this technique for the sodium D lines broadened by xenon and neon perturbers. The values for the broadening constants obtained in this manner are in reasonable agreement with values from several previous studies utilizing more traditional techniques.
Oil and Gas Wells and Pipelines on U.S. Wildlife Refuges: Challenges for Managers

The increased demand for oil and gas places a burden on lands set aside for natural resource conservation. Oil and gas development alters the environment locally and on a much broader spatial scale depending on the intensity and extent of mineral resource extraction. The current increase in oil and gas exploration and production in the United States prompted an update of the number of pipelines and wells associated with oil and gas production on National Wildlife Refuge System (NWRS) lands. We obtained geospatial data on the location of oil and gas wells and pipelines within and close to the boundaries of NWRS lands (units) acquired as fee simple (i.e. absolute title to the surface land) by the U.S. Fish and Wildlife Service. We found that 5,002 wells are located in 107 NWRS units and 595 pipelines transect 149 of the 599 NWRS units. Almost half of the wells (2,196) were inactive, one-third (1,665) were active, and the remainder of the wells were either plugged and abandoned or the status was unknown. Pipelines crossed a total of 2,155 kilometers (1,339 miles) of NWRS fee simple lands. The high level of oil and gas activity warrants follow up assessments for wells lacking information on production type or well status with emphasis on verifying the well status and identifying abandoned and unplugged wells. NWRS fee simple lands should also be assessed for impacts from brine, oil and other hydrocarbon spills, as well as habitat alteration associated with oil and gas, including the identification of abandoned oil and gas facilities requiring equipment removal and site restoration.
Structure, Reactivity, and Density Functional Theory Analysis of the Six-Electron Reductant, [(C5Me5)2U]2(μ-η6:η6-C6H6), Synthesized via a New Mode of (C5Me5)3M Reactivity

The sterically crowded (C5Me5)3U complex reacts with KC8 or K/(18-crown-6) in benzene to form [(C5Me5)2U]2(-6:6-C6H6), 1, and KC5Me5. These reactions suggested that (C5Me5)3U could be susceptible to (C5Me5)1- substitution by benzene anions via ionic salt metathesis. To test this idea in the synthesis of a more conventional product, (C5Me5)3U was treated with KN(SiMe3)2 to form (C5Me5)2U[N(SiMe3)2] and KC5Me5. 1 has long U-C(C5Me5) bond distances comparable to (C5Me5)3U, and it too is susceptible to (C5Me5)1- substitution via ionic metathesis: 1 reacts with KN(SiMe3)2 to make its amide-substituted analogue {[(Me3Si)2N](C5Me5)U}2(-6:6-C6H6), 2. Complexes 1 and 2 have nonplanar C6H6-derived ligands sandwiched between the two uranium ions. 1 and 2 were examined by reactivity studies, electronic absorption spectroscopy, and density functional theory calculations. [(C5Me5)2U]2(-6:6-C6H6) functions as a six-electron reductant in its reaction with 3 equiv of cyclooctatetraene to form [(C5Me5)(C8H8)U]2(-3:3-C8H8), (C5Me5)2, and benzene. This multielectron transformation can be formally attributed to three different sources: two electrons from two U(III) centers, two electrons from sterically induced reduction by two (C5Me5)1- ligands, and two electrons from a bridging (C6H6)2- moiety.
Sofic shifts with synchronizing presentations

Abstract A sofic shift S is a symbolic dynamical system that can be viewed as a set of all bi-infinite sequences obtained by reading the labels of all bi-infinite paths in a finite directed labeled graph G . The presentation G is synchronizing if for every vertex v there is a word x v such that every path in G labeled with x v has v as a terminal vertex. We present an example of a subshift of finite type that has no unique minimal deterministic presentation and we show that if a sofic shift has a synchronizing, deterministic presentation (sdp), then it has a unique minimal one. Irreducible sofic shifts, subshifts of finite type and nonwandering systems have synchronizing, deterministic presentations. We give an intrinsic characterization of a sofic shift S that has an sdp in terms of the syntactic monoid M ( S ) of the factor language F ( S ) of S . Another characterization of sofic shifts with sdp's is given in terms of the predecessor sets. We show that a sofic shift can have at most one bi-synchronizing presentation.
Weak-coupling phase diagram of the two-chain Hubbard model

We present a general method for determining the phase diagram of systems of a finite number of one-dimensional Hubbard-like systems coupled by single-particle hopping with weak interactions. The technique is illustrated by detailed calculations for the two-chain Hubbard model, providing controlled results for arbitrary doping and interchain hopping. Of nine possible states which could occur in such a spin-1/2 ladder, we find seven at weak coupling. We discuss the conditions under which the model can be regarded as a one-dimensional analog of a superconductor. \textcopyright{} 1996 The American Physical Society.
Using AG theory to model a S/I/N tunnel junction

Abstract We have measured the spin polarized tunneling conductance of a thin Al/Al2O3/amorphous GdxSi1−x planar tunnel junction at T=25 mK in parallel magnetic field H⩽3.0 T. Abrikosov–Gorkov theory is a better model for the thin superconducting Al electrode than previously used Bardeen–Cooper–Schrieffer theory. As the magnetic field is increased, we find the best fit to the data by modelling a transition from a superconductor with gap (α 1).
Investigation and reduction of personnel exposure levels in Bavarian water supply facilities

Abstract Since 2001, the protection against natural radiation is implemented in German law. The limit of the annual effective dose is 20 mSv. But the annual effective dose due to radon exposure is only limited at certain work places, e.g., mines and water supply facilities. The federal states are responsible for the observation of this law. Consequently, all Bavarian water supply facilities were investigated with regard to radon concentrations in indoor air as well as radon exposure of the staff working in these buildings. In 0.7% of all water supply facilities, the staff were exposed to levels that exceed the limit of 20 mSv/a. In 1.7% of the water supply facilities, the personnel exposure level was between 6 and 20 mSv/a. There are several remedial actions that have proven to be successful: it is inexpensive to reduce the radon exposure by reducing the time spent in the units; and the buildings can be ventilated with stationary or mobile devices by blowing fresh air directly to the working place. In one case, a combination of an effective ventilation system with a separating wall between the water purification basins and the water supply control centre reduced the annual effective dose of the process controller from 100 to about 6 mSv.
Novel strategies for fabricating reduced fat foods: Heteroaggregation of lipid droplets with polysaccharides

Abstract This study describes the formation of emulsion-based materials with novel textural characteristics by controlled heteroaggregation of food-grade colloidal particles and polymers. Heteroaggregation was induced by mixing a suspension of colloidal particles (β-lactoglobulin-coated lipid droplets) with a solution of polymer molecules (pectin) under conditions where the particles and polymers had similar charges (pH 7) or opposite charges (pH 4). The mean particle size, microstructure, flow behavior, and shear modulus of the mixtures formed depended on particle-to-polymer ratio and solution pH. At pH 4, negatively charged pectin molecules were attracted to the surfaces of positively charged protein-coated droplets leading to particle aggregation, increased viscosity, and gel formation, which were attributed to bridging flocculation. At pH 7, pectin molecules were not attracted to the droplet surfaces, but there was still an increase in emulsion viscosity and gel strength above a critical pectin concentration due to depletion flocculation. Bridging flocculation (pH 4) led to more extensive particle aggregation, higher viscosities, and stronger gels than depletion flocculation (pH 7). The presence of pectin in the emulsions had little impact on their microstructure or lipid digestion rate in a simulated gastrointestinal model. This study has important implications for the creation of reduced fat foods, and the development of foods, cosmetics, personal care, and other products with novel properties.
Nyquist stability conditions for laser feedback amplifiers with Gaussian or Lorentzian gain profiles

In principle, high-gain laser amplifiers with negative feedback can perform spatial signal-processing operations analogous to the temporal operations performed by electronic operational amplifiers. In practice, it is difficult to achieve stability (prevent self-oscillation). Stability analysis is difficult because the overall transfer function for such an amplifier is a function not of one but of three frequencies: two spatial and one temporal. In the analysis presented here, an integral-equation formulation that specifically includes finite-lens-aperture effects permits stability analysis in terms of the temporal frequency alone. A Nyquist approach is then used to derive sufficient conditions for stability of a class of laser feedback amplifiers.
Implementation and performance evaluation of Selective Repeat ARQ for WiMAX NS-2 model

With the steady development of WiMAX based broadband wireless access networks, complete and accurate simulation studies become crucial. In an effort to further improve our ns-2 simulation model for mobile WiMAX, we have implemented a selective repeat automatic retransmission request (SR-ARQ) mechanism into our model and evaluated its performance and accuracy. In this paper, we present the design and implementation methodology of the WiMAX SR-ARQ simulation model in ns-2 and discuss its accuracy via extensive simulation studies. Our evaluation clearly shows that SR-ARQ achieves increased successful packet delivery ratio and goodput, which is true for both non-saturated channels and saturated channels. In each case a cost of increased bandwidth consumption and latency overhead for received packets is also quantitatively analyzed. We believe the implementation of SR-ARQ in the ns-2 simulation model and its evaluation studies will provide profound empirical values to WiMAX field test studies.
(R)-mevalonate excretion in human and rat urines

(R)-Mevalonate was identified by radioenzymatic assay in human and rat urines. This was confirmed by spectrophotometric enzymatic assay of an ether extract of human urine. The average excretion rate of (R)-mevalonate in humans was 1.7 mumol/24 hr which corresponds to 29% of the glomerular filtration rate. In anesthetized rats the average rate of (R)-mevalonate excretion was 350 pmol/min, corresponding to 44% of the glomerular filtration rate. These rates were not affected by the sex of the subjects or animals. After bilateral nephrectomy, the concentration of (R)-mevalonate in rat serum increased within 2 hr to a new level that was 5 times that of sham-operated controls. Nephrectomized rats showed a decrease in their tolerance to an intravenous load of mevalonate. These data show that (R)-mevalonate is normally excreted in the urine of humans and rats. Urinary excretion of (R)-mevalonate should therefore be taken into account in in vivo studies on the metabolism of this compound.
Hybrid Navier-Stokes/Free-Wake Method for Modeling Blade-Vortex Interactions

Techniques for accurate capturing of rotor blade-vortex-interaction phenomena are discussed. A number of algorithmic enhancements have been systematically examined, including geometric conservation law, refined metric and Jacobian computations, higher-order spatial and second-order temporal accuracy schemes, and embedded grids. The use of the geometric conservation law and refined metric computation were found to reduce nonphysical mass accumulation errors. These enhancements improve stability and accuracy of the higher-order schemes near far-field boundaries and in the vicinity of highly skewed cells. Embedded grids with an increased grid density were found to improve the predictions. It was also observed that the free-wake model (and, in particular, the determination of the trailing tip-vortex release point) plays a critical role in the blade-vortex-interaction prediction.
Refined structure of Cro repressor protein from bacteriophage lambda suggests both flexibility and plasticity.

The structure of the Cro repressor protein from phage lambda has been refined to a crystallographic R-value of 19.3% at 2.3 A resolution. The re fined model supports the structure as originally described in 1981 and provides a basis for comparison with the Cro-operator complex described in the accompanying paper. Changes in structure seen in different crystal forms and modifications of Cro suggest that the individual subunits are somewhat plastic in nature. In addition, the dimer of Cro suggests a high degree of flexibility, which may be important in forming the Cro-DNA complex. The structure of the Cro subunit as determined by NMR agrees reasonably well with that in the crystals (root-mean-square discrepancy of about 2 A for all atoms). There are, however, only a limited number of intersubunit distance constraints and, presumably for this reason, the different NMR models for the dimer vary substantially among themselves (discrepancies of 1.3 to 5.5 A). Because of this variation it is not possible to say whether the range of discrepancies between the X-ray and NMR Cro dimers (2.9 to 7.5 A) represent a significant difference between the X-ray and solution structures. It has previously been proposed that substitutions of Tyr26 in Cro increase thermal stability by the "reverse hydrophobic effect", i.e. by exposing 40% more hydrophobic surface to solvent in the folded form than in the unfolded state. The refined structure, however, suggests that Tyr26 is equally solvent exposed in the folded and unfolded states. The most stabilizing substitution is Tyr26-->Asp and in this case it appears that interaction with an alpha-helix dipole is at least partly responsible for the enhanced stability.
Velocity distribution functions for a bidisperse, sedimenting particle-gas suspension

Abstract The velocity distribution function of a dilute bidisperse particle-gas suspension depends on the relative magnitudes of the viscous relaxation time, τv, and the time between successive collisions, τv. The The distribution functions in the two asymptotic limits, τc ⪡ τv and τv ⪡ τc, which were analysed previously are qualitatively very different. In the former limit, the leading-order distributions are Gaussian distributions about the mean velocity of the suspension, whereas in the latter case the distributions for the two species are singular at their respective terminal velocities. Here, we calculate the properties of the suspension for intermediate values of τv/τc by approximating the distribution function as a composite Gaussian distribution. This distribution reduces to a Gaussian distribution in the limit τv ⪡ τc, in agreement with previous asymptotic analysis. In the intermediate regime, however, the composite Gaussian has a non-zero skewness, which is a salient feature of the distribution in the limit τv ⪡ τc. We have also performed numerical calculations using the direct-simulation Monte Carlo method. The approximate values for the moments of the velocity distribution obtained using the composite Gaussian compare well with the full numerical solutions for all values of τv/τc.
Ring Expansion and Contraction of a Two-Carbon Bridged Spiropentane

The reactions of tricyclo[4.1.0.01,3]heptan-4-one (5) and two related systems with diazomethane and m-CPBA were examined in order to determine the relative reactivity and migratory aptitudes for the three compounds. The reactions of 5 with diazomethane and m-CPBA yielded new derivatives of the tricyclo[5.1.0.01,3]octane ring system that showed that migration of cyclopropylcarbinyl is favored over cyclopropyl migration in this system. Photolysis of 5-diazotricyclo[4.1.0.01,3]heptan-4-one (23) in methanol and dimethylamine did not lead to ring contraction to the tricyclo[3.1.0.01,3]hexane ring system, but an interesting product was derived from an unusual rearrangement process in the photolysis in dimethylamine. Matrix photolysis of 23 at 15 K gave a decrease in the diazo band at 2085 cm-1 and the appearance of a new band at 2117 cm-1, which is a normal position expected for a small-ring ketene such as cyclopropylketene. Thus, matrix photolysis appears to have yielded a derivative of the previously unknown ...
Behind the Mask: How the World Survived SARS, the First Epidemic of the 21st Century

Behind the Mask: How the World Survived SARS, the First Epidemic of the Twenty-First Century recounts the outbreak of Severe Acute Respiratory Syndrome (SARS) that swept through much of the world, especially Asia, in 2003. The author does a superb job of telling the reader about what was occurring before SARS appeared, what happened during the outbreak, and what efforts are underway to prevent its return. The author has blended research results and interviews with frontline staff, particularly healthcare providers, into 20 nicely interlaced chapters. The stage for this commentary is a timeline of events, starting November 16, 2002, with the first known case of SARS in Guangdong Province, China, and ending in December 2003–January 2004 with 4 cases of SARS and the slaughtering of ≈10,000 civets in Guangdong Province. Where possible, the author avoided the use of medical terms and jargon and provides helpful lay translations where their use was unavoidable. As a result, the book is accessible to readers both inside and outside the healthcare arena. The information presented in the book is, for the most part, current and accurate; different views and beliefs are presented when necessary. There are minor typographical mistakes as well as a few incorrect statements, such as in chapter 1, page 6, where the author refers to past public health efforts to eradicate viruses. The author states that smallpox virus and poliovirus have both been eradicated and that both are now bioterrorism agents. However, despite tremendous progress through efforts of many governments and public and private entities, poliovirus has yet to be eradicated and is not regarded as a bioterrorism agent at this time. With regard to SARS, however, the author successfully portrays the human side of the outbreak response—a response heralded as unparalleled by many of the involved officials. Dr Carlo Urbani, the World Health Organization (WHO) physician in Vietnam who worked tirelessly and who was an eventual casualty of SARS, is among the many heroes who are featured in this book. Lesser-known facts, such as the thought processes that led to identifying SARS, are also provided. For example, before the SARS coronavirus was shown to be the causative agent, the outbreak was thought to be caused by either avian influenza or chlamydia. The reader is made aware of all of the challenges posed by the SARS virus, such as the delay in recognizing that there was an outbreak, the difficulties in diagnosing and reporting the disease and obtaining specimens, the breadth and scope of national and international collaboration and coordination, and not knowing the causative agent. This book does a nice job of giving readers a flavor of the experiences faced by persons at WHO, persons at the country ministry level, individual healthcare providers, and SARS patients. I highly recommend this book, especially to anyone who was not directly involved in the SARS outbreak response; they too can share the experience of the global community response to a disease that was first recognized in 1 province of China.
Breastfeeding and Antiepileptic Drugs

IMPORTANCE Exposure to antiepileptic drugs during pregnancy is associated with adverse effects on psychomotor development. OBJECTIVES To determine whether signs of impaired development appear already during the first months of life in children exposed prenatally to antiepileptic drugs, and to explore potential adverse effects of antiepileptic drug exposure through breastfeeding. DESIGN, SETTING, AND PARTICIPANTS Mothers at 13 to 17 weeks of pregnancy were recruited in the population-based, prospective Norwegian Mother and Child Cohort Study from 1999 to 2009. The mothers reported on their child’s motor and social skills, language, and behavior using items from standardized screening tools at 6 months (n = 78 744), 18 months (n = 61 351), and 36 months (n = 44 147) of age. The mothers also provided detailed information on breastfeeding during the first year. MAIN OUTCOMES AND MEASURES The risk of adverse development in children according to maternal or paternal epilepsy was estimated as the odds ratio with corresponding 95% confidence interval, adjusted for maternal age, parity, education, smoking, breastfeeding, depression/anxiety, folate supplementation, and congenital malformation in the child. RESULTS At age 6 months, infants of mothers using antiepileptic drugs (n = 223) had a higher risk of impaired fine motor skills compared with the reference group (11.5% vs 4.8%, respectively; odds ratio = 2.1; 95% CI, 1.3–3.2). Use of multiple antiepileptic drugs compared with the reference group was associated with adverse outcome for both fine motor skills (25.0% vs 4.8%, respectively; odds ratio = 4.3; 95% CI, 2.0–9.1) and social skills (22.5% vs 10.2%, respectively; odds ratio = 2.6; 95% CI, 1.2–5.5). Continuous breastfeeding in children of women using antiepileptic drugs was associated with less impaired development at ages 6 and 18 months compared with those with no breastfeeding or breastfeeding for less than 6 months. At 36 months, prenatal antiepileptic drug exposure was associated with adverse development regardless of breastfeeding status during the first year. Children of women with epilepsy who did not use antiepileptic drugs and children of fathers with epilepsy had normal development at 6 months. CONCLUSIONS AND RELEVANCE Prenatal exposure to antiepileptic drugs was associated with impaired fine motor skills already at age 6 months, especially when the child was exposed to multiple drugs. There were no harmful effects of breastfeeding. Women with epilepsy should be encouraged to breastfeed their children irrespective of antiepileptic drug treatment.
Computer applications to radioactive-seed: brain-tumor implants.

Abstract Malignant brain tumors, in general, and anaplastic astrocytoma and glioblastoma multiforme in particular, have been highly refractory to conventional treatments including surgery, chemotherapy and external-beam irradiation. Although better local control can be achieved with high-dose, external beam irradiation, necrosis of normal brain tissue reduces the quality of life and survival. In order to localize the radiation dose given to brain tumors, the temporary implantation of 1251 and 192Ir seeds is undergoing clinical trials at several medical centers. Computers play a key role in this treatment modality: in addition to being essential for image reconstruction of CT scans, a computer is used to reconstruct a tumor volume from outlined regions on individual cuts; a programable calculator is used in conjunction with a stereotaxic head holder to obtain the coordinates of the radioactive seeds; a radiation-therapy, treatment-planning computer is used to optimize the radioactive-seed positions and strengths, and to generate the corresponding dose distribution.
Antimicrobial Prophylaxis for Wounds and Procedures in the Emergency Department

Emergency physicians are often confronted with situations in which a patient with an acute injury is at high risk for an infection. Although most traumatic wounds have a low risk for developing infection, certain types of high-risk trauma justify antimicrobial prophylaxis. This article reviews antimicrobial wound infection prophylaxis for high-risk traumatic wounds, including the prevention of rabies and tetanus. Prophylaxis to prevent infections related to invasive procedures in the emergency department is also addressed.
Dkk1 and Dkk2 regulate epicardial specification during mouse heart development.

Background Dkk1 and Dkk2 interact with LRP5 and LRP6 to modulate canonical Wnt signaling during development, and are known to be expressed in the developing heart. However, a loss-of-function mutation in either gene by itself produces no discernable heart phenotype.
Utilization of Remotely Sensed Data to Map and Evaluate Turfgrass Stress Associated with Drought

Research was conducted to assess the suitability of using multispcctral scanner data to evaluate turfgrass stress associated with irrigation management. Tall fescue (Festuca arundinacea Schreb) was...
Non-conventional modification of low density lipoproteins: chemical models for macrophage recognition of oxidized LDL

To define the structural and chemical criteria governing recognition of oxidized LDL (oxLDL) by mouse peritoneal macrophages (MPM), we exposed LDL to novel chemical modification agents that induce defined neutralizing and non-neutralizing alterations of lysine as models for distinct apoB adducts present in oxLDL. We found some exceptions to the usual notion that neutralization of lysine positive charges is the principal determinant governing MPM recognition. In addition, competitive binding experiments using chemically modified 125I-LDL preparations revealed that, whereas some modifications engendered recognition principally by the classical scavenger receptor class A (SRA), as seen for acetylated LDL (acLDL), chemical models of advanced aldehydic modifications of LDL led instead to MPM uptake mainly by oxLDL receptors distinct from SRA.
Using Microcomputers in the Undergraduate Laboratory

A computer-controlled experimental psychology investigation suitable for use in an undergraduate laboratory is described. The investigation examines the relationship between aesthetic preference and speed of reaction in making choices between colors generated on a video monitor. No special interfacing to the computer is required. The techniques have been used successfully and with great reliability to introduce microcomputer use to undergraduate psychology students.
Reproductive ecology of the nine‐spined stickleback from south‐central Alaska

The life cycle of the nine-spined stickleback Pungitius pungitius from Airolo Lake, Alaska, was studied using samples taken during 1993-1994 and 1997-1998. Pungitius pungitius was actively reproducing in late May and ceased reproductive activities by late June. Spawning adults were 2+ years old. Contrary to an earlier report, the data indicate that an individual female oviposits all of her ovulated eggs (i.e. an entire clutch) into a male's nest during one spawning episode. There was a trade-off between clutch size and egg size without concomitant variation in clutch mass between two years. The results are compared to those from other studies.
Lactational Response of Dairy Cows Inoculated with Live Adapted Rumen Microorganisms

Abstract Two experiments involved 28 lactating Holstein cows to measure the response to intraruminal inoculation with live rumen microorganisms adapted specifically to the fermentation of starch substrate. In Trial 1, 12 cows at 110 days in lactation were paired and allotted randomly within pairs either to a control or to receive a single inoculation of 355ml of live adapted rumen microorganisms. Fat-corrected milk production was 9.7% higher for cows with adapted rumen microorganisms over the 8 wk following inoculation. In Trial 2, 16 cows were allotted equally between two groups prior to freshening. One group was inoculated as in Trial 1 at 4 to 7 days postpartum with the other group serving as control. Fat-corrected milk was higher for inoculated cows over the 22 wk following treatment (25.4 versus 22.1 kg/day). Milk fat and solids-not-fat tended to increase in inoculated cows resulting in increases in total solids. Silage and concentrate intake increased slightly in the inoculated group, but dry matter intakes were not significantly different. Cows inoculated with adapted rumen microorganism produced 781kg more milk and 39kg more fat than controls during the total lactation.
Neighborhood Exposure to Toxic Releases: Are There Racial Inequities?

This paper explores the use of empirical evidence to determine whether the exposure of minorities to environmental risks constitutes aversive racism. Connections are drawn between definitions of aversive racism and statistical approaches to research into the relationship between race and risk, paying particular attention to the influence of both non-racial discrimination and industrial location factors. Federal judicial and executive remedies to aversive racism are examined in light of the standards of evidence presented. An empirical study of the connection between race and exposure to toxic releases is then presented for Census block groups in Georgia and Ohio. It was found that the significance of race depends on the breadth of the explanatory model used in the analysis. A model of overall exposure to toxic releases shows that race is significant in a narrow model of discrimination but not in a broader model including industrial location factors. However, a model of targeting of minorities in the recent location of toxics-emitting facilities fails to show discrimination in any of the regression analyses. These findings support the view that environmental justice concerns cannot be addressed through reform of siting processes; broader remedies involving more stringent protection of exposure to toxic emissions are more likely to be effective.
Efficient algorithms for scheduling semiconductor burn-in operations

In this paper, we study the problem of scheduling semiconductor burn-in operations, where burn-in ovens are modeled as batch processing machines. A batch processing machine is one that can process up to B jobs simultaneously. The processing time of a batch is equal to the largest processing time among all jobs in the batch. We present efficient dynamic programming-based algorithms for minimizing a number of different performance measures on a single batch processing machine. We also present heuristics for a number of problems concerning parallel identical batch processing machines and we provide worst case error bounds.
Structure of the nuclease domain of ribonuclease III from M. tuberculosis at 2.1 A

RNase III enzymes are a highly conserved family of proteins that specifically cleave double-stranded (ds)RNA. These proteins are involved in a diverse group of functions, including ribosomal RNA processing, mRNA maturation and decay, snRNA and snoRNA processing, and RNA interference. Here we report the crystal structure of the nuclease domain of RNase III from the pathogen Mycobacterium tuberculosis. Although globally similar to other RNase III folds, this structure has some features not observed in previously reported models. These include the presence of an additional metal ion near the catalytic site, as well as conserved secondary structural elements that are proposed to have functional roles in the recognition of dsRNAs.
Xenon-Vacancy Defect Clusters in Copper

A computer investigation of the stability of clusters of substitutional xenon atoms in copper shows that xenon clusters are energetically unstable in the absence of adjacent vacancies in the surrounding copper lattice. The stability of various clusters increases as the ratio of vacancies to xenon atoms increases. The efficiency of the stabilization due to the vacancies is markedly affected by the geometrical distribution of the vacancies in the xenon-vacancy clusters. Die Stabilitat von substitutionellen Xenon-Atom-Clustern in Kupfer wurde mit Hilfe einer elektronischen Rechenanlage untersucht. Es ergab sich, das die Xenon-Cluster ohne die gleichzeitige Anwesenheit von den Clustern angegliederten Leerstellen instabil gegen den Zerfall in isolierte Defekte sind. Die Stabilitat der verschiedenen Cluster ist um so groser, je groser das Verhaltnis von Leerstellen zu Xenon-Atomen ist. Die stabilisierende Wirkung der Leerstellen hangt wesentlich von ihrer raumlichen Verteilung ab.
Importance of Student Social Behavior in the Mission Statements, Personnel Preparation Standards, and Innovation Efforts of State Departments of Education

We examined the extent to which state departments of education are including (a) goals for student social behavior in their mission statements; (b) criteria for individual student, classroom, and schoolwide behavior support in certification standards for general education teachers, special education teachers, and principals; and (c) state initiatives focused on improving student social behavior. Web-based information from state departments of education from all 50 states and from the District of Columbia were reviewed in the fall of 2004. Results indicated that only 16 states (31%) include a focus on student social behavior in their mission statements. Individual student behavior support practices were identified in the curriculum for general educators in 30 (59%) states and for special educators in 39 (76%) states. Classroom behavior support practices were required for general education teachers in 39 (76%) states and for special educators in 40 (78%) states. Schoolwide behavior support practices were mo...