cssi/SciSciGPT-SciSciNet huggingface dataset:
Comparative study on conformational stability and subunit interactions of two bacterial asparaginases.

Abstract The denaturation and reconstitution of Erwinia carotovora and Escherichia coli l -asparaginases has been followed by optical rotatory dispersion, circular dichroism and analytical ultracentrifugation. Denaturation in urea results in dissociation of the native enzyme (mol. wt. 140 000 approx.) to produce unfolded subunits (mol. wt. 35 000 approx.); the Erwinia l -asparaginase subunits can be refolded by dilution or dialysis in alkaline conditions, pH 10.5, without aggregation to the active tetramer, to give a rather unstable solution of a monomer possibly in equilibrium with dimer. These alkaline-reconstituted subunits undergo a conformational change to a more ordered state in the presence of sodium dodecylsulphate, similar to those produced by the action of sodium dodecylsulphate on the native enzyme. If the denatured subunits are reconstituted in the pH range 5.0–7.5, the enzymically active tetramer is reformed in up to 80% yield, depending upon the conditions of temperature and concentration. Kinetic data for these various transitions suggest that dissociation is a rate-limiting step while conformational changes of the polypeptide chains are relatively much more rapid. The possible significance of these different rates of change to therapeutic considerations is discussed.
Dynamics of delaminated beams

In this paper, we present a new model for composite beams with through-width delaminations. Shear effect and rotary inertia terms, as well as bending-extension coupling, are taken into account in the governing equations of vibration. Nonlinear interaction, due piecewise linear spring models between the delaminated sublaminates, is also included. Based on this model, eigensolutions for vibrations of intact and delaminated beams are found analytically. Dynamic behavior predicted by this model is then compared with previously reported experimental results. Better agreements with the experimental results are found. Discrepancies among previously proposed models are explained without difficulty.
A Welfare-To-Wellness-To-Work Program

This cross-sectional, exploratory study evaluates and describes a welfare-to-wellness-to-work program developed by a nurse located in the western United States. Adults (N = 34) aged 23–57-years-old, who participated in the program from 2001 to 2007, completed a demographic/health survey and were interviewed. From open-ended, semistructured questions, the study identified key themes related to the program. Content analysis of the data revealed significant insights about the program's curriculum, positive changes for the participants, obstacles and challenges they confronted, employment success, and a motivational tool (affirmations). Participants gained overwhelming benefit from the program and enhanced their functioning as individuals, family members, and parents.
Cyclopolymerization reactions of diallyl monomers: exploring electronic and steric effects using DFT reactivity indices.

The regioselectivity in the cyclopolymerization of diallyl monomers is investigated using DFT-based reactivity indices. In the first part, the experimentally observed mode of cyclization (exo versu...
Stress wave propagation in bone

Abstract The traveling wave characteristics for a single compressive pulse were studied in fresh and embalmed human long bones. The stress wave was generated by the longitudional impact of a steel ball on one end of a bone and was monitored by bonded strain gages. The dynamic properties, namely velocity, attenuation coefficient and dispersion were correlated with the mineral density, porosity, and cross-sectional area of the specimens. Statistically significant relationships were found between several of these parameters. These stress wave propagation characteristics are important for our understanding of the dynamic loading of bone and they may also provide a basis for the development of noninvasive techniques for studies of diseased or fractured bone.
‘Whose name's on the awning?’ Gender, entrepreneurship and the American diner

While, in recent years, women-owned businesses have become increasingly common, entrepreneurship itself remains a deeply gendered institution, and one that is constructed through everyday practice rooted in space and place. The purpose of the present study is to explore the woman-owned diner as a distinct environment in and through which configurations of gender and entrepreneurship are mutually constituted, socially enacted, and spatially defined. Drawing upon a case study of a present-day diner in Worcester, Massachusetts, I trace the life narratives of two working-class women through their emergence as entrepreneurs in the diner industry. I reflect upon the distinctive space of the woman-owned diner as it is produced through the interaction between the gendered body-subjects of women owners, the social meaning of ‘feeding work’, and the spatial character of the diner institution. Through the gendered social practice of diner ownership, these two women have overcome substantial social, economic and geog...
A zone of non-proliferating cells at a lineage restriction boundary in Drosophila

The use of X-ray-induced mitotic recombination to genetically mark individual cells and their descendants during development has led to the discovery of lineage restriction boundaries in Drosophila imaginal disks, dividing the disks into areas called compartments. Clones of cells initiated after a given developmental stage are unable to grow across these boundaries, even if provided with a growth rate advantage over the remaining cells. It has been suggested that cells within compartments are distinguished by the differential activation of selector genes and that the lineage restrictions are maintained by adhesivity differences between the cells in different compartments, but other mechanisms have not been ruled out. Recently a discrete population of cells with unusual permeability properties has been described along an intersegmental lineage restriction boundary in Oncopeltus, suggesting that a lineage restriction could be maintained by a zone of cells which present a barrier to clone growth. Here we demonstrate by autoradiography the presence of a narrow zone of non-proliferating cells (ZNC) coincident with the presumptive wing margin in the Drosophila wing disk, and suggest that this could account for the observed lineage restriction between presumptive dorsal and ventral surfaces of the wing. As the anterior/posterior compartment boundary does not coincide with a ZNC, the results indicate that different lineage boundaries may be maintained by different mechanisms.
Identification of Arginine Residues in Peptides by 2D-IR Echo Spectroscopy

The CN stretching vibrations of the guanidyl group in the arginine dipeptide side chain are examined by two-dimensional infrared spectroscopy. In D2O, the spectra display two distinct diagonal peaks. These nearly degenerate modes undergo ultrafast energy transfer. The energy-transfer rate was determined directly from the 2D-IR spectra to be 1/2.1 ps–1. The cross peaks in 2D-IR arising from the energy transfer provide a definitive identification of arginine in larger proteins. An example of arginine in the transmembrane protein M2, found in influenza viruses, is given.
Energy Efficiency Retrofits for U.S. Housing: Removing the Bottlenecks

U.S.housing accounted for over 22 percent of the country’s total primary energy consumption in 2009, which equated to more than $2,000 per household and $229 billion in aggregate expenditure. It appears these amounts could be reduced substantially, with benefits to both household budgets and the environment’s well-being.This paper’s goal is to evaluate the alternative mechanisms that could expedite energy efficiency retrofits for U.S. housing. We begin by evaluating the evidence that significant improvements in the energy efficiency of existing U.S. housing are feasible, both technologically and financially. We compare the relatively optimistic positions taken inMcKinsey (2009), EPRI (2009), andHarcourt, Brown, and Carey (2011) versus theless optimistic appraisal in Allcott and Greenstone (2012). We conclude thatsignificant energy savings do appear to be feasible, technologically and financially. The remainder of the paper considers the bottlenecks that hamper energy-saving investments for the residential sector. We focus on imperfect information and loan market failures as the two key factors. We evaluate the state of the art with respect to scoring and assessment tools for energy-saving investments and the On-Bill, PACE, and Solar programs to facilitate secured loans. The discussion concludes with a series of proposals to overcome the bottlenecks.
Aspirin, Statins, or Both Drugs for the Primary Prevention of Coronary Heart Disease Events in Men: A Cost–Utility Analysis

Background Aspirin and statins are both effective for primary prevention of coronary heart disease (CHD), but their combined use has not been well studied. Objective To perform a cost-utility analysis of the effects of aspirin therapy, statin therapy, combination therapy with both drugs, and no pharmacotherapy for the primary prevention of CHD events in men. Design Markov model. Data sources Published literature. Target population Middle-aged men without a history of cardiovascular disease at 6 levels of 10-year risk for CHD (2.5%, 5%, 7.5%, 10%, 15%, and 25%). Time horizon Lifetime. Perspective Third-party payer. Interventions Low-dose aspirin, a statin, both drugs as combination therapy, or no therapy. Outcome measure Cost per quality-adjusted life-year gained. Results of base-case analysis For 45-year-old men who do not smoke, are not hypertensive, and have a 10-year risk for CHD of 7.5%, aspirin was more effective and less costly than no treatment. The addition of a statin to aspirin therapy produced an incremental cost-utility ratio of 56,200 dollars per quality-adjusted life-year gained compared with aspirin alone. Results of sensitivity analysis Excess risk for hemorrhagic stroke and gastrointestinal bleeding with aspirin, risk for CHD, the cost of statins, and the disutility of taking medication had important effects on the cost-utility ratios. Limitations Several input parameters, particularly adverse event rates and utility values, are supported by limited empirical data. Results are applicable to middle-aged men only. Conclusions Compared with no treatment, aspirin is less costly and more effective for preventing CHD events in middle-aged men whose 10-year risk for CHD is 7.5% or higher. The addition of a statin to aspirin therapy becomes more cost-effective when the patient's 10-year CHD risk before treatment is higher than 10%.
Structure and Seasonality of Nearctic Culex pipiens Populations

The abundance and structure of urban autogenous and anautogenous populations of Culex pipiens mosquitoes were documented systematically in Boston, MA, during three successive years. Autogenous larvae become abundant mainly in enclosed sites and anautogenous larvae in sites that provide free access and egress. Both populations begin to proliferate when the water temperature exceeds 15 degrees C during June. Larval anautogenous mosquitoes increase in abundance 10-fold in two weeks and autogenous in three weeks. Although anautogenous larvae rapidly disappear after mid-August when winter diapause commences, the abundance of autogenous larvae continues to increase until mid-October. The forms generally are reproductively isolated in nature but occasionally hybridize during August and thereafter. Anautogenous females feed mainly on birds; autogenous females generally never feed on blood; and hybrid females appear to feed indiscriminately on avian or mammalian hosts. Such northern C. p. pipiens mosquitoes range as far south as 33 degrees N. Taken together, these observations suggest that C. p. pipiens-borne pathogens may proliferate in the northern United States until mid-August and affect human hosts thereafter. Intensity of transmission decreases toward the south.
Clustering of low-energy conformations near the native structures of small proteins

Recent experimental studies of the denatured state and theoretical analyses of the folding landscape suggest that there are a large multiplicity of low-energy, partially folded conformations near the native state. In this report, we describe a strategy for predicting protein structure based on the working hypothesis that there are a greater number of low-energy conformations surrounding the correct fold than there are surrounding low-energy incorrect folds. To test this idea, 12 ensembles of 500 to 1,000 low-energy structures for 10 small proteins were analyzed by calculating the rms deviation of the Calpha coordinates between each conformation and every other conformation in the ensemble. In all 12 cases, the conformation with the greatest number of conformations within 4-A rms deviation was closer to the native structure than were the majority of conformations in the ensemble, and in most cases it was among the closest 1 to 5%. These results suggest that, to fold efficiently and retain robustness to changes in amino acid sequence, proteins may have evolved a native structure situated within a broad basin of low-energy conformations, a feature which could facilitate the prediction of protein structure at low resolution.
Susceptibility and triggering scenarios at a regional scale for shallow landslides

Abstract The work aims at identifying susceptible areas and pluviometric triggering scenarios at a regional scale in Calabria (Italy), with reference to shallow landsliding events. The proposed methodology follows a statistical approach and uses a database linked to a GIS that has been created to support the various steps of spatial data management and manipulation. The shallow landslide predisposing factors taken into account are derived from (i) the 40-m digital terrain model of the region, an ∼ 15,075 km2 extension; (ii) outcropping lithology; (iii) soils; and (iv) land use. More precisely, a map of the slopes has been drawn from the digital terrain model. Two kinds of covers [prevalently coarse-grained (CG cover) or fine-grained (FG cover)] were identified, referring to the geotechnical characteristics of geomaterial covers and to the lithology map; soilscapes were drawn from soil maps; and finally, the land use map was employed without any prior processing. Subsequently, the inventory maps of some shallow landsliding events, totaling more than 30,000 instabilities of the past and detected by field surveys and photo aerial restitution, were employed to calibrate the relative importance of these predisposing factors. The use of single factors (first level analysis) therefore provides three different susceptibility maps. Second level analysis, however, enables better location of areas susceptible to shallow landsliding events by crossing the single susceptibility maps. On the basis of the susceptibility map obtained by the second level analysis, five different classes of susceptibility to shallow landsliding events have been outlined over the regional territory: 8.9% of the regional territory shows very high susceptibility, 14.3% high susceptibility, 15% moderate susceptibility, 3.6% low susceptibility, and finally, about 58% very low susceptibility. Finally, the maps of two significant shallow landsliding events of the past and their related rainfalls have been utilized to identify the relevant pluviometric triggering scenarios. By using 205 daily rainfall series, different triggering pluviometric scenarios have been identified with reference to CG and FG covers: a value of 365 mm of the total rainfall of the event and/or 170 mm/d of the rainfall maximum intensity and a value of 325 mm of the total rainfall of the event and/or 158 mm/d of the rainfall maximum intensity are able to trigger shallow landsliding events for CG and FG covers, respectively. The results obtained from this study can help administrative authorities to plan future development activities and mitigation measures in shallow landslide-prone areas. In addition, the proposed methodology can be useful in managing emergency situations at a regional scale for shallow landsliding events triggered by intense rainfalls; through this approach, the susceptibility and the pluviometric triggering scenario maps will be improved by means of finer calibration of the involved factors.
Temperature sounding from the absorption spectrum of CO2 at 4.3 microns

A new method is described for obtaining the temperature profile in the stratosphere and lower mesosphere from observations of the absorption spectrum of the high J lines of carbon dioxide at 4.3 microns. This concept is based upon the measurement of the integrated absorption of individual CO2 lines whose strengths depend strongly on temperature and that the absorption of these lines are obtained from measurements of the solar or stellar spectrum through an atmospheric path. The technique involves a rapidly converging iterative process in which the equivalent widths of the individual vibration-rotation lines of CO2 are used. Theoretical calculations are presented for balloon and satellite observations using a model atmosphere. Experimental results are given from spectra obtained with a balloon-borne Fourier interferometer spectrometer in which the sun was observed at low zenith angles. The experimental results are compared to rocketsonde data.
Content-based retrieval in picture archiving and communication systems.

A Content-Based Retrieval Architecture (COBRA) for picture archiving and communication systems (PACS) is introduced. COBRA improves the diagnosis, research, and training capabilities of PACS systems by adding retrieval by content features to those systems. COBRA is an open architecture based on widely used health care and technology standards. In addition to regular PACS components, COBRA includes additional components to handle representation, storage, and content-based similarity retrieval. Within COBRA, an anatomy classification algorithm is introduced to automatically classify PACS studies based on their anatomy. Such a classification allows the use of different segmentation and image-processing algorithms for different anatomies. COBRA uses primitive retrieval criteria such as color, texture, shape, and more complex criteria including object-based spatial relations and regions of interest. A prototype content-based retrieval system for MR brain images was developed to illustrate the concepts introduced in COBRA.
Suppression of humoral immune responses by 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin intercalated in smectite clay

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a highly toxic environmental contaminant found in soils and sediments. Because of its exceptionally low water solubility, this compound exists predominantly in the sorbed state in natural environments. Clay minerals, especially expandable smectite clays, are one of the major component geosorbents in soils and sediments that can function as an effective adsorbent for environmental dioxins, including TCDD. In this study, TCDD was intercalated in the smectite clay saponite by an incipient wetness method. The primary goal of this study was to intercalate TCDD in natural K-saponite clay and evaluate its immunotoxic effects in vivo. The relative bioavailability of TCDD was evaluated by comparing the metabolic activity of TCDD administered in the adsorbed state as an intercalate in saponite and freely dissolved in corn oil. This comparison revealed nearly identical TCDD-induced suppression of humoral immunity, a well-established and sensitive sequela, in a mammalian (mouse) model. This result suggests that TCDD adsorbed by clays is likely to be available for biouptake and biodistribution in mammals, consistent with previous observations of TCDD in livestock exposed to dioxin-contaminated ball clays that were used as feed additives. Adsorption of TCDD by clay minerals does not appear to mitigate risk associated with TCDD exposure substantially. Environ. Toxicol. Chem. 2011;30:2748–2755. © 2011 SETAC
Polymer ultrathin films by self-assembly: bound perfluorinated monolayers and their modification using in situ derivatization strategies

Abstract Siloxane-based grafted copolymers and terpolymers derivatized with pendant dithioalkyl chains, or with both perfluoroalkyl and dithioalkyl side chains, are shown to assemble spontaneously on gold surfaces, yielding bound, anisotropic, polymer ultrathin films. Polymer monolayer assembly is driven by alkyl chain anchoring to solid surfaces by chemisorption from dilute organic media. Limited miscibility between perfluoroalkyl and alkyl hydrocarbon side chains as well as between the siloxane backbone and each side chain component induces a stratified anisotropic monolayer structure. Angular-dependent XPS data show that the siloxane backbone lies primarily between surface-exposed perfluorinated grafts and hydrocarbon chains tethered underneath at the solid surface. Wetting data indicate the hydrophobic influence of perfluoro surface enrichment. Ellipsometry measurements on these films yields 20–30 A thicknesses. Reflection FT-IR spectra evidence enhanced alignment of perfluoroalkyl grafts in these films as compared to bulk spectra. Once assembled on solid surfaces, these polymer monolayers can be further derivatized with a number of different molecules, providing a defined, stable, organic foundation for surface modification of various types.
Genotype-specific alterations in vascular smooth muscle cell function in cystic fibrosis piglets

Abstract Background The most common CF-causing mutations interfere with CFTR trafficking from the endoplasmic reticulum (CFTR-F508del) or prematurely terminate transcription (CFTR-null). We suspected that genotype-specific patterns of CFTR expression would have differential effects on smooth muscle cell calcium signaling and hence vascular tone. We hypothesized that compared to wild-type or CFTR-null aorta, aorta from CFTR-F508del (dF) piglets will have reduced endoplasmic reticulum calcium mobilization and decreased vasoconstriction. Methods Aortic reactivity was assessed by myography, and ratiometric calcium imaging was performed in isolated vascular smooth muscle cells. Results Aorta from dF piglets had reduced myogenic tone (P 3 receptors decreased wild-type and CFTR-null responses to levels seen in dF aorta. Compared to wild-type cells, dF-expressing smooth muscle cells had reduced calcium transients, while CFTR-null cells had decreased baseline intracellular calcium concentrations. Conclusions Expression of CFTR-F508del interferes with smooth muscle cell calcium handling and decreases aortic responsiveness.
Characterization of the deposition and materials parameters of thin-film TiNi for microactuators and smart materials

Development of smart materials and materials for microelectromechanical systems (MEMS) are complicated by the need to grow dissimilar active or adaptive materials in close proximity. This entails discouraging unwanted chemical and physical interactions that prevent production of the appropriate phases. An important component of these systems will be thin-film shape memory effect TiNi. This article discusses the characterization of the deposition of thin film TiNi for these applications as well as the cycling speed for MEMS.
Revenue Sharing in Russia

The Russian system of federalism is in the midst of a difficult transition from a highly centralized to a more decentralized regime. It is a reasonable proposition that the final solution will somehow be a kind of assignment system, but it is unclear what path will have to be followed to reach that stated goal. The present system of revenue sharing is based on shared taxes and subventions. It is a two-tiered system, with the federal government laying down the rules for central–oblast sharing, and each oblast making the rules for the local governments within its jurisdiction. This paper updates a World Bank analysis of the revenue-sharing system in the Russian Federation, using actual data for 1992 and the most current tax-sharing rules and adds some empirical evidence to what is known about the intra-oblast dimension of revenue sharing.
"Das Ausland grinst dich an": Zum Thema der fließenden Grenzen in Volker Brauns Stück Limes. Mark Aurel

Volker Braun's Limes. Mark Aurel, a short play in five acts with a prologue and an epilogue, appeared in 2002. The Latin title refers to the frontier line or "wall" between the Roman empire and Germany, and to one of its protectors, the Roman emperor and Stoic philosopher Marcus Aurelius. The juxtaposition of "stoic" and "emperor" evokes an obvious dichotomy and thus a recurring theme in Volker Braun's ouevre: the question of how to reconcile brute political force exercised by a superpower and practical morality and concerns for common humanity. Braun, the political activist from the former GDR, presents both a historical play about a short timespan during the reign of Marcus Aurelius and a highly contemporary tragedy about refugees from fear who cause fear. These "barbarians" – the ancient Germanic tribes or their modern counterparts from the impoverished parts around the globe – invade the crumbling confines of those who live comfortably. Marcus Aurelius' conflicted character, his vascillation between political duty and altruism, is reflected in his dialogues with an aggressively confrontational partner or alter ego, the Mephistophelian realist Galen who is his constant escort and physician. In short, Braun, in his customary provocative manner, presents the dialectics of an updated, revamped "Hinze and Kunze"-relationship. Against the backdrop of the brittle Limes-borderline, the diametrically opposed voices in Marc Aurel reveal the gradual dissolution of his own moralistic inner line which eventually leads to his death: tranquility and politics are ultimately irreconcilable in a world that is ruled by its own barbaric mechanisms.
InAsP/InP strained quantum wells grown by gas-source molecular beam epitaxy on InP(100) and (111)B substrates

The strained InAsP/InP system can be a viable alternative material to the quaternary InGaAsP on InP because the composition and thickness of InAsP can be controlled independently in gas- source MBE and because strain could provide another degree of freedom in device design. We have developed an in situ technique for composition determination in InAsP and have shown that InAsP/InP (100) strained multiple quantum wells exhibit quantum-confined Stark effect in the 1.3 micrometers region. The existence of an internal piezoelectric field in InAsP/InP (111)B strained single quantum wells is demonstrated by the blue energy shift from carrier screening in photoluminescence spectra.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Modified MINDO/3 13C chemical shift calculations for simple hydrocarbons

Calculations of 13C chemical shifts in some simple hydrocarbons have been carried out using the GIAO approach in the MINDO/3 semiempirical formalism. In order to achieve reasonable agreement with experiment it is necessary to modify (increase) the vacant orbital energies in the MINDO/3 calculation in order to reduce the magnitude of the paramagnetic contribution, and to also modify this dominant term by generally reducing it as a function of the number of hydrogen and carbon atoms bonded to the resonant nucleus in question. For a set of 34 resonant nuclei of the simpler hydrocarbons, agreement with experiment of the order of 7.8 ppm is attained; however, pathological cases such as cyclopropane and some simple allenes continue to cause problems, increasing the standard deviation of the full set to 12.5 ppm. Our results indicate that the MINDO/3 approach is as viable for 13C chemical shift calculations as other semiempirical approaches, all of which seem currently to be limited to a standard deviation of the order of 10 ppm.
Eye Color and Fast Food Consumption

Worthy (1974) and Markle (1976) reported that individuals with dark eyes are more responsive to arousing stimuli in the environment than are individuals with light eyes. The environment abounds with television advertisements and billboard signs advertising fast food, as well as the restaurants themselves, and peer or family pressure t o eat there. Wc hypothesized that dark-eyed people respond to their over-all environments more by eating more fast foods. We gave a questionnaire on fast food consumption to 38 male and 22 female Caucasians who were federal government employees, ranging in age from 19 to 65 yr. Subjects self-reported their eye color: 32 had dark eyes (mean age = 40 yr.; 65.6% male), and 28 had light eyes (mean age = 36 yr.; 60.7% male). They then stated on a 9-point hedonic scale ("dislike extremely" to "like extremely") how much they liked each of 24 different fast foods, e.g., hamburgers, pizza, French fries, etc. Then they reported how often they ate each at a fast food restaurant. All frequencies were converted to number per year. The mean hedonic rating across all items differed only slightly .by eye color: darkeyed people averaged 7.3 (moderate liking) and light-eyed ones 7.1. Total annual consumption differed more but not significantly: 314.2 fast food items per year for dark-eyed subjects compared to 214.9 for light-eyed ones (T. = 1.66, d f = 45.82, P = .104). However, for 17 of the 24 items, the mean frequencies differed in the predicted direction, with dark-eyed subjects consuming more (with the sign test, P = .032). And the variability of the two groups differed markedly. The dark-eyed group had a standard deviation for annual frequency of 301.1, whereas the light-eyed group,had one of 144.5 ( F = 4.34, P < .001). The significance of this difference was further confirmed by the Scheffe test for the heterogeneity of variance, as described by Smits (1979). With 1 and 9 d f , the mean F ratio was 7.9 ( P < .025). That 17 of the 24 items differed in the predicted direction provides modest support for the current hyp~~thesis. That darkeyed people are more variable among themselves suggests that their behavior correlates more strongly with the naturally varying levels of stimulation in the environment. .. . . . REFERENCES
The transfer of Boophilus microplus (Acarina: Ixodidae) from infested to uninfested cattle under field conditions

The transfer of larvae and adult males of the cattle tick, Boophilus microplus, from infested to uninfested cattle, has been demonstrated under field conditions. The role of host to host transfers in the transmission and epidemiology of anaplasmosis and babesiosis is discussed.
Volcano Theory of Pulsars

IT has recently become clear1 that at least some white dwarfs are likely to have convective envelopes. Neutron star models2 are generally similar to white dwarf models, so it is possible that neutron stars will also have superadiabatic temperature gradients in their outer layers. Convection in the ordinary sense cannot occur in neutron star envelopes, however, because these envelopes are solid3. How will heat be transported through a solid mantle of a neutron star which is convectively unstable? It seems reasonable to expect that one or more weak points will develop through which liquid material from the core will pour out to the surface. In other words, energy will be transported by volcanoes.
Management and outcome of patients with malignant salivary gland tumors.

Purpose Refined imaging technology, the use of external beam radiation, neutron beam therapy, and chemotherapy, has altered management strategies for patients with salivary gland malignancies during the past 2 decades. Although treatment remains primarily surgical, optimal therapeutic regimens have yet to be fully realized. The purpose of this investigation is to report our experience with the management of patients with a variety of malignant salivary gland neoplasms that were treated with various combinations of surgery, radiation, and chemotherapy and to review treatment outcome in an effort to identify predictors of survival and locoregional control. Materials and Methods The records of all patients with malignant salivary gland tumors presenting for treatment at our institution between 1992 and 2002 were retrospectively reviewed. Variables were collected and outcome measures were defined in terms of overall survival, disease-free survival, and locoregional control. Descriptive statistics were compiled and statistically evaluated. Survival was described using the Kaplan-Meier method. Prognostic factors were assessed using the Cox proportional hazards model. Clinical and reconstructive factors were reviewed. Results Eighty-five patients (35 males and 50 females) ranging in age from 16 to 89 years (mean, 58.6 years) met the criteria for inclusion in the study. The majority of tumors were located in the parotid gland (n = 42), with a significant minority located in the minor salivary glands (n = 29), followed by the submandibular gland (n = 8) and the sublingual gland (n = 6). Mucoepidermoid carcinoma was the most common neoplasm (n = 40). More than half of the patients presented in early-stage disease (stage I = 36, stage II = 17, stage III = 8, stage IV = 25). All patients were treated with surgery as the primary modality. Neck dissection was performed in 29% of patients, and more than half (56%) were treated with adjuvant external beam radiation therapy to a dose of 50 to 70 Gy. Patients were, in general, immediately reconstructed at the time of ablation using composite free tissue transfer when appropriate, local/regional rotational flaps, or maxillary obturators. The disease-free survival rate and locoregional control rate at 5 years were 77% and 86%, respectively. Stage ( P = .0017), grade ( P = .00044), cervical lymph node metastasis ( P = .03), and age ( P = .01) proved to make a statistically significant contribution when describing outcome. Neither site ( P = .5), the presence of positive margins ( P = .3), nor perineural invasion ( P = .7) had a significant impact on survival. Conclusions The treatment of salivary gland malignancies remains primarily surgical, although adjunctive radiotherapy may play an important role in those patients with advanced-stage disease. This study confirms the contributions of stage, grade, age, and cervical metastasis for describing survival. The benefits of combined modality therapy awaits prospective clinical trials.
Socio-demographic Characteristics of Individuals with History of Crack Cocaine Use in the US General Population

This study explores socio-demographic characteristics of individuals with history of crack cocaine use. Data from the 29th Round of General Social Survey was used. Respondents with history of crack cocaine use were compared to respondents without such history. T test was applied to identify differences between groups. Approximately 6 % of respondents reported lifetime history of crack cocaine use. Groups with and without history of crack cocaine use differed significantly in gender, marital status, education, income distribution, employment, health perception, family and financial satisfaction, criminal history, happiness, sexual history, history of injection drug use, and HIV testing. There were no significant differences for race. The study provides insights that could improve identification and prevention of substance use disorders.
Detection of covalent enzyme-substrate complexes of nitrilase by ion-spray mass spectroscopy

Abstract Nitrilase from Rhodococcus ATCC 39484 was found to consist of two species of Mr 40 258 ±2 and 40 388 ±2 Da. When the enzyme was incubated with nitrile substrates and the reaction quenched with acid, higher Mr, species were observed. The mass differences were consistent with addition of a substrate molecule to each species. These results represent the first reported demonstration that this, or any other nitrilase forms a covalent intermediate with its substrates. The observation that the intermediate, suggested to be either a thioimidate or an acylenzyme, can be trapped by acidification indicates that the rate of breakdown of the intermediate is rate-limiting.
Effects of indomethacin on uterine capillary permeability and blastocyst development in rabbits

Increased capillary permeability at implantation sites was demonstrated in rabbits by extravasation of intravascular blue dye on day 7 of pregnancy. Subcutaneous administration of indomethacin (Id, 8 mg/kg twice daily) on days 4-6 of pregnancy inhibited this uterine blueing response and appeared to reduce the size of implantation swellings. To test the latter observation blastocyst diameter and development of the embryonic disk were assessed at 144 hr post coitum. In females receiving indomethacin at the dose level which inhibited uterine blueing, blastocysts were significantly smaller than those from control females. Developmental staging of embryonic disks revealed only slight differences between the smaller (Id-treated) blastocysts and control blastocysts. No effect of Id was seen on ovarian function as judged by luteal weights and plasma progesterone and estradiol levels. Since the major biological effects of indomethacin are due to its inhibition of prostaglandin synthesis, it appears that prostaglandins may play a role in the uterine response to blastocyst stimulation and in the expansion of blastocysts in the rabbit.
Advanced diffractive optics for X-ray microscopy

Transmission X-ray microscopy relies on diffractive X-ray optics to achieve high spatial resolution for the investigation of many types of specimens, both organic and inorganic. We present several nanofabrication methods to produce high quality diffractive X-ray optics for X-ray imaging.
Cyclic voltammetry of quinolinium salts and related compounds: correlation with structure and anticancer activity.

Cyclic voltammetry data were obtained for 12 salts of quinolines, one pyridine, and one open-chain imine which possess varying degrees of anticancer activity. The structural features include sidechain bis(2-methylthio)vinyl, 2-methylthio-2-aminovinyl, dithioacetic acid, 2-quinolylvinyl, 2-styrylvinyl, and guanidine sulfide functionalities. Reduction potentials ranged from −0.43 to −1.08 V. The electrochemical results are correlated with structure. A possible mechanism of anticancer action is addressed.
Intermetatarsal fat pad sign: radiographic aid to diagnosis of occult tarsometatarsal joint injuries.

AJR 2009; 192:W36–W37 0361–803X/09/1921–W36 © American Roentgen Ray Society Intermetatarsal Fat Pad Sign: Radiographic Aid to Diagnosis of Occult Tarsometatarsal Joint Injuries Lisfranc tarsometatarsal fracture–disloc­ ations are well­described injuries usually resulting from forced plantar flexion or direct blow or crush trauma to the forefoot. Although this is a relatively rare injury, timely recognition is essential because misdiagnosis can lead to chronic pain and instability in this patient population. Lisfranc injuries account for less than 1% of all fractures and have a reported incidence of one per 55,000 persons; however, the overall incidence may be more common than is generally recognized because misdiagnosis has been reported to occur in approximately 20% of all cases [1, 2]. Conventional radiographs, including weight­ bearing­view images, can reveal fractures of the metatarsal bases, and dis placement of the bases in advanced cases, but can be unreli­ able in the detection of subtle injuries and iso lated ligamentous injuries without bone frac tures [3]. Subtle malalignment of the tarsal–metatarsal junction can be difficult to diagnose radiographically. Norfray et al. [4] have even suggested that 1–2 mm of tarso­ metatarsal malalignment may be normal. The reason for this diagnostic dilemma lies in the fact that overlapping shadows, inappropriate positioning, and sub optimal exposure parame­ ters can make correct evaluation of osseous land marks difficult [4]. Despite its limitations in revealing the full extent of tarsometatarsal injury, radiography is often the first examination performed after the initial clinical examination. Mis diagnosis is highest in cases of isolated ligamentous injury with no visible fracture on the radiograph and in which metatarsal cuneiform offset may be subtle or absent. We have pro­ vided images of such a case, and we describe an interesting soft­tissue radiographic find­ ing that, to the best of our knowledge, has not been previously described. We have called this the “intermetatarsal fat pad sign.” Similar to the sail sign of olecranon and coronoid fossae fat pad displacement seen with intra­ articular injury to the elbow, we show that edema and hemorrhage from a Lisfranc ligamentous injury may also produce a radio­ graphically apparent displaced inter metatarsal fat pad (Fig. 1). We believe that awareness of the intermetatarsal fat pad sign may be of aid in the diagnosis of subtle radio graphic pre­ sentations of Lisfranc injury. Vincent Timpone Michael Tall Andrew Puckett David Grant U.S. Air Force Medical Center Travis Air Force Base, CA 94535
Liquid Crystals: VII. Smectic-Nematic Transition Temperature as a Function of Alkyl End Group Length in p-Phenylene Di-p-n-alkoxybenzoates

The Sm-N transition temperatures of the C1-C12 homologs of some p-phenylene di-p-n-alkoxybenzoates were studied. For three homologous series of these esters (unsubstituted, methyl-substituted, and ...
Simultaneous Faults on Three-Phase Systems

The method of symmetrical components now so extensively used to determine short-circuit currents and stability limits during transient conditions for three-phase transmission systems when a fault involving one or more of the three conductors occurs at any one point of the system, has been extended to apply to three-phase systems during simultaneous faults at two or more points of the system. A general equivalent circuit is developed to replace, in the positive phase diagram, two simultaneous faults involving any combination of the six conductors. An approximate equivalent circuit to be used with the d-c. calculating table when resistance is neglected is also given. Special equivalent circuits are employed to rep, lace two simultaneous faults and the lines upon which they occur, when the lines are unloaded feeders radiating from a common point or lines of equal impedances bussed at both ends. The methods and formulas given in this paper were developed in answer to such questions as the following: 1. Which is a more severe shock to a system, a double line-to-ground fault on one circuit or two single line-to-ground faults occurring simultaneously on two separate circuits? 2. Do simultaneous double line-to-ground faults which involve the same phases, a and b, on two circuits, result in more or less ground current than faults which involve phases a and b on one cir-cuit and phases b and c on the other?
Effect of Dielectric and Liquid on Plasma Sterilization Using Dielectric Barrier Discharge Plasma

Plasma sterilization offers a faster, less toxic and versatile alternative to conventional sterilization methods. Using a relatively small, low temperature, atmospheric, dielectric barrier discharge surface plasma generator, we achieved ≥6 log reduction in concentration of vegetative bacterial and yeast cells within 4 minutes and ≥6 log reduction of Geobacillus stearothermophilus spores within 20 minutes. Plasma sterilization is influenced by a wide variety of factors. Two factors studied in this particular paper are the effect of using different dielectric substrates and the significance of the amount of liquid on the dielectric surface. Of the two dielectric substrates tested (FR4 and semi-ceramic (SC)), it is noted that the FR4 is more efficient in terms of time taken for complete inactivation. FR4 is more efficient at generating plasma as shown by the intensity of spectral peaks, amount of ozone generated, the power used and the speed of killing vegetative cells. The surface temperature during plasma generation is also higher in the case of FR4. An inoculated FR4 or SC device produces less ozone than the respective clean devices. Temperature studies show that the surface temperatures reached during plasma generation are in the range of 30°C–66°C (for FR4) and 20°C–49°C (for SC). Surface temperatures during plasma generation of inoculated devices are lower than the corresponding temperatures of clean devices. pH studies indicate a slight reduction in pH value due to plasma generation, which implies that while temperature and acidification may play a minor role in DBD plasma sterilization, the presence of the liquid on the dielectric surface hampers sterilization and as the liquid evaporates, sterilization improves.
An Assessment Instrument to Measure Geospatial Thinking Expertise

Spatial thinking is fundamental to the practice and theory of geography, however there are few valid and reliable assessment methods in geography to measure student performance in spatial thinking. This article presents the development and evaluation of a geospatial thinking assessment instrument to measure participant understanding of spatial relations within a geographic context. The instrument is a test consisting of thirty question items, with the purpose to help identify the knowledge sets, thinking skills, and characteristics typical at different levels of competency. The performance score is used to classify participants along an expertise continuum, novice to expert. Generally, students performing at the expert level consist of graduate students while novices are at the grade nine level, although several anomalies are discussed. The broad instructional application of this assessment is to benchmark student performance and the level of understanding of geospatial concepts.
Laser Excitation Of Atomic Inner-Shells By Coherent Processes With Implications For X-Ray Lasers

Experimental studies of multiphoton processes using high-brightness ultraviolet excimer laser sources are interpreted in terms of a new mechanism for producing highly excited states of atomic inner-shells. The macroscopic electric field associated with a spatially and temporally coherent intense laser pulse can be made to equal or exceed the Coulomb field experienced by the electrons in the outer-shell. The model predicts that all of the electrons in the outermost sub-shell will execute an ordered coherent motion that can couple strongly to inner-shell electrons to produce highly excited inner-shell states and vacancies. This may, in favorable cases, result in population inversions for transitions in the 100 to 1,000 eV range. The experimental basis for this mechanism, scaling estimates based on this analysis, and potential applications of this technique are presented.
Synthesis, Characterization, and Reaction Chemistry of PtCl2[P(m-C6H4SO3Na)3]2, an Alkyne Hydration Catalyst

The preparation and reactions of cis-PtCl2(TPPTS)2 (TPPTS = P(m-C6H4SO3Na)3) in aqueous solution are described. In the absence of excess Cl-, cis-PtCl2(TPPTS)2 exists as a mixture with 20% of cis-Pt(Cl)(H2O)(TPPTS)2+; the aqua complex was prepared independently by reaction with Ag+. As a result of the aquation cis-PtCl2(TPPTS)2 is slightly acidic. Increasing the pH for a solution of cis-PtCl2(TPPTS)2 leads to Pt2(TPPTS)4(μ-OH)22+; a subsequent decrease in pH leads to cis-Pt(OH2)2(TPPTS)22+ and, ultimately, cis-PtCl2(TPPTS)2. All of these complexes were characterized by 31P and 195Pt NMR. cis-PtCl2(TPPTS)2 functions as an effective hydration catalyst for the water-soluble alkynes 4-pentyn-1-ol and 3-pentyn-1-ol. Both hydrations are stereospecific to 5-hydroxy-2-pentanone. Hydration of 4-pentyn-1-ol occurs by a 5-exo-dig mechanism, while hydration of 3-pentyn-1-ol occurs through a 5-endo-dig mechanism.