cssi/SciSciGPT-SciSciNet huggingface dataset:
Antenatal Microbiome: Potential Contributor to Fetal Programming and Establishment of the Microbiome in Offspring.

Background: Endogenous and exogenous exposures during fetal development have potential to impact birth and health outcomes of offspring. Accumulating evidence suggests exposures may alter the antenatal microbiome and subsequently alter the microbiome and health of offspring. Objectives: The purpose of this integrative review is to summarize and critically evaluate the current state of knowledge regarding the assessment of the antenatal microbiome on the health of human offspring. The article provides a brief summary of the known factors affecting the human microbiome and studies that assessed relationships between the antenatal microbiome and health outcomes of the offspring. Methods: An integrative review was conducted to examine human research studies that focused on the antenatal microbiome and the health of the offspring using the electronic databases PubMed/MEDLINE and CINAHL from 2004 to the present. Results: In addition to the known individual factors that are associated with establishment of the microbiome, the results of the integrative review suggest that medications (including antibiotics) and comorbidities (including infectious diseases, diet, socioeconomic status, and exposure to pollutants) should also be measured. Discussion: The composition of the antenatal microbiome at various time points and body sites may be important mediators of short- and long-term health outcomes in offspring. In order to advance our understanding of the role of the antenatal microbiome on health and disease risk of the offspring, it will be important to further elucidate the composition of a healthy microbiome and specific mechanisms that contribute to altered health in later life.
Efficient Sampling for Gaussian Graphical Models via Spectral Sparsification

Motivated by a sampling problem basic to computational statistical inference, we develop a toolset based on spectral sparsification for a family of fundamental problems involving Gaussian sampling, matrix functionals, and reversible Markov chains. Drawing on the connection between Gaussian graphical models and the recent breakthroughs in spectral graph theory, we give the first nearly linear time algorithm for the following basic matrix problem: Given an n× n Laplacian matrix M and a constant −1 ≤ p ≤ 1, provide efficient access to a sparse n× n linear operator C such that M ≈ CC>, where ≈ denotes spectral similarity. When p is set to −1, this gives the first parallel sampling algorithm that is essentially optimal both in total work and randomness for Gaussian random fields with symmetric diagonally dominant (SDD) precision matrices. It only requires nearly linear work and 2n i.i.d. random univariate Gaussian samples to generate an n-dimensional i.i.d. Gaussian random sample in polylogarithmic depth. The key ingredient of our approach is an integration of spectral sparsification with multilevel method: Our algorithms are based on factoring M into a product of well-conditioned matrices, then introducing powers and replacing dense matrices with sparse approximations. We give two sparsification methods for this approach that may be of independent interest. The first invokes Maclaurin series on the factors, while the second builds on our new nearly linear time spectral sparsification algorithm for random-walk matrix polynomials. We expect these algorithmic advances will also help to strengthen the connection between machine learning and spectral graph theory, two of the most active fields in understanding large data and networks.
Estimating temporal dynamics of human emotions

Sentiment analysis predicts a one-dimensional quantity describing the positive or negative emotion of an author. Mood analysis extends the one-dimensional sentiment response to a multi-dimensional quantity, describing a diverse set of human emotions. In this paper, we extend sentiment and mood analysis temporally and model emotions as a function of time based on temporal streams of blog posts authored by a specific author. The model is useful for constructing predictive models and discovering scientific models of human emotions.
Interaction Games: A Unified Analysis of Incomplete Information, Local Interaction and Random Matching Games

Incomplete information, local interaction and random matching games all share a common structure. A type or player interacts with various subsets of the set of all types/players. A type/player's total payoff is additive in the payoffs from these various interactions. This paper describes a general class of interaction games and shows how each of these three types of games can be understood as special cases. Techniques and results from the incomplete information literature are translated into this more general framework; as a by-product, it is possible to give a complete characterization of equilibria robust to incomplete information (in the sense of Kajii and Morris [1995]) in many player binary action co-ordination games. Only equilibria that are robust in this sense [1] can spread contagiously and [2] are uninvadable under best response dynamics in a local interaction system. A companion paper, Morris [1997], uses these techniques to characterize features of local interaction systems that allow contagion.
Data Structures and Algorithms for Extended State Space and Structural Level Reduction of the GSPN Model

This paper extends the applicability of exact analysis of the GSPN model by providing methods to improve the time and space complexity of both state space and structural level reduction. For state space level reduction, we maximize the concurrent firing of immediate transitions. For structural level reduction, we minimize the number of generated replicas for timed transitions by using branch and bound techniques to create concurrent replicas that simulate the firing of the timed transition followed by the simultaneously firing of multiple immediate transitions.
Evaluation of a Regionalization Approach for Daily Flow Duration Curves in Central and Southern California Watersheds1

Hope, Allen and Ryan Bart, 2011. Evaluation of a Regionalization Approach for Daily Flow Duration Curves in Central and Southern California Watersheds. Journal of the American Water Resources Association (JAWRA) 48(1): 123-133. DOI:10.1111/j.1752-1688.2011.00597.x Abstract: Discontinuities in flow regimes of ephemeral rivers in California make the modeling of daily flow duration curves (FDCs) in ungauged watersheds challenging. A regionalization approach previously developed for perennial and ephemeral watersheds in Portugal was tested in central and southern California. This approach, which is based on the theory of total probability, requires the prediction of three key flow variables in ungauged watersheds: the percentage of time the river is dry, the nonzero flow equalled or exceeded 80% of the time, and the mean daily flow for nonzero flows. Data from 41 watersheds in California were used to develop and validate regression equations for these three metrics. The methodology included an “all possible models” regression approach, an extensive set of watershed descriptors as potential independent variables, and two different methods for constructing observed FDCs. Suitable regression models could not be identified for predicting any of the required flow metrics. The contrasting results from the studies in Portugal and California were primarily attributed to differences in the aridity of watersheds in the two samples.
The Properties of Thyroglobulin XIX. THE EQUILIBRIUM BETWEEN GUINEA PIG THYROGLOBULIN AND ITS SUBUNITS

Abstract Guinea pig thyroglobulin (19 S) shows a time-dependent dissociation into half-sized (12 S) subunits at neutral pH in 0.1 M KCl. The reaction is completely reversible between 1 and 23° and is endothermic since higher temperature favors the 19 S species. The rate and equilibrium of association have been measured by light scattering and velocity centrifugation, respectively. Increasing the salt concentration increases the rate and the equilibrium constant of association. The velocity constant of association is strongly dependent on pH, decreasing rapidly as the pH is raised from 6.4 to 8.4. The degree of dissociation of guinea pig thyroglobulin increases with decreasing iodine content.
Generalized (s-Parameterized) Weyl Transformation

A general canonical transformation of mechanical operators of position and momentum is considered. It is shown that it automatically generates a parameter s which leads to a generalized (or s-parameterized) Wigner function. This allows one to derive a generalized (s-parameterized) Moyal brackets for any dimensions. In the classical limit the s-parameterized Wigner averages of the momentum and its square yield the respective classical values. Interestingly enough,in the latter case the classical Hamilton-Jacobi equation emerges as a consequence of such a transition only if there is a non-zero parameter s.
Incorporating thermal regimes into environmental flows assessments: modifying dam operations to restore freshwater ecosystem integrity

SUMMARY 1. Despite escalating conflict over fresh water, recent years have witnessed a growing realisation that human society must modify its behaviour to ensure long-term ecological vitality of riverine ecosystems. In response, ecologists have been increasingly asked to guide instream flow management by providing ‘environmental flow’ prescriptions for sustaining the ecological integrity of riverine systems. 2. Environmental flows are typically discussed in the context of water releases from dams and water allocation for extraction (such as for urban use or irrigation), where there is general agreement that rivers need to exhibit some resemblance of natural flow variability necessary to support a functioning ecosystem. Although productive dialogue continues on how best to define environmental flows, these discussions have been focused primarily on water quantity without explicit consideration of many components of water quality, including water temperature – a fundamental ecological variable. 3. Many human activities on the landscape have modified riverine thermal regimes. In particular, many dams have modified thermal regimes by selectively releasing hypolimnetic (cold) or epilimnetic (warm) water from thermally stratified reservoirs to the detriment of entire assemblages of native organisms. Despite the global scope of thermal alteration by dams, the prevention or mitigation of thermal degradation has not entered the conversation when environmental flows are discussed. 4. Here, we propose that a river’s thermal regime is a key, yet poorly acknowledged, component of environmental flows. This study explores the concept of the natural thermal regime, reviews how dam operations modify thermal regimes, and discusses the ecological implications of thermal alteration for freshwater ecosystems. We identify five major challenges for incorporating water temperatures into environmental flow assessments, and describe future research opportunities and some alternative approaches for confronting those challenges. 5. We encourage ecologists and water managers to broaden their perspective on environmental flows to include both water quantity and quality with respect to restoring natural thermal regimes. We suggest that scientific research should focus on the comprehensive characterisation of seasonality and variability in stream temperatures, quantification of the temporal and spatial impacts of dam operations on thermal regimes and clearer elucidation of the relative roles of altered flow and temperature in shaping ecological patterns and processes in riverine ecosystems. Future investigations should also concentrate on using this acquired knowledge to identify the ‘manageable’ components of the thermal regime, and develop optimisation models that evaluate management
Experimental Thin-Film, Etched-Circuit Rectenna

The design and experimental evaluation of a 2.45 GHz thin-film etched-circuit rectenna based upon the use of Mylar or Kapton F film is discussed. Efficiencies of 85% and DC power output to mass ratios of one watt per gram have been achieved.
Lateral load distribution in I-girder bridges

Abstract The results of a new lateral load distribution formula to be applied in the analysis or design of steel girders are compared with recently published field test data as well as the current AASHTO load distribution factor method. The developed formula was the result of a study of lateral load distribution in a bridge superstructure employing the finite element analysis techniques. The finite element models were developed to represent the actual geometry of the bridge deck and analyzed to obtain a better understanding of the elastic behavior of the concrete slab-on-steel girder highway bridges. The developed load distribution formula compares well with field data in predicting the behavior of bridge superstructures under highway loadings. Therefore, this paper will assist bridge engineers and researchers in predicting the actual load distribution and bending moments in I-girder highway bridges.
The Aging Worker in a Changing Environment: Organizational and Individual Issues

Abstract The impact of an aging workforce raises the biggest issues facing employers today. Middle age and older workers will become increasingly prevalent in the work place. In this article using five approaches to defining older workers as an organizing framework we review a number of these employment issues. The approaches include chronological, functional, psychosocial, organizational and life-span. Physical and cognitive changes are addressed. Research supports the notion that older workers have the capacity to continue making contributions at work. A primary theme, regardless of the specific issue, is the predominant importance of individual differences. A lifespan approach accommodates individual differences in career patterns. The prevailing viewpoint is that adult and older adult workers need to be considered on an individual basis both in terms of career choices and planning as well as in terms of employment or promotional opportunities. Attention is given to the human resource policies that may impact older workers such as performance management, selection and training.
Limitations of regional myocardial thallium clearance for identification of disease in individual coronary arteries

The purpose of this study was to critically evaluate the usefulness of postexercise regional myocardial thallium-201 clearance for identifying disease in individual coronary arteries. Exercise and redistribution planar imaging studies were performed in 114 subjects, including 19 normal volunteers and 95 patients undergoing cardiac catheterization (70 with and 25 without greater than or equal to 50% narrowing in one or more coronary arteries). Thallium clearance was measured from predefined myocardial regions corresponding to the left anterior descending, left circumflex and right coronary arteries and was expressed as the percent decrease in activity at 4 h, assuming monoexponential clearance. In regions perfused by a normal or insignificantly diseased coronary artery, mean 4 h clearance was 58.9 +/- 9.4% for normal volunteers, 43.1 +/- 15.5% for catheterized patients without coronary artery disease and 36.3 +/- 24.9% for catheterized patients with coronary artery disease (p less than 0.001 patients with coronary artery disease versus normal volunteers). Clearance from normal regions was significantly associated with two measures of exercise performance: percent of predicted maximal heart rate achieved (r = 0.49) and exercise duration (r = 0.35). In regions perfused by a stenotic coronary artery, mean clearance was lower (31.1 +/- 19.8%) but was not significantly different from that in normal regions in the same patients. Clearance from diseased regions was also associated with maximal exercise heart rate (r = 0.28) and exercise duration (r = 0.41), but not with percent coronary artery stenosis (r = 0.02). After taking exercise performance into account, the number of diseased vessels or the presence or absence of disease in a given vessel had little influence on regional thallium clearance. Although measurement of regional post-exercise thallium clearance may help to identify stenotic coronary arteries in selected patients, variability related to exercise performance and other physiologic and technical factors greatly limits the clinical usefulness of absolute thallium clearance measurements.
Heterogeneity of the MDCK Cell Line and Its Applicability for Influenza Virus Research

Single-cell clones have been established from the MDCK cell line, characterized for their morphology and evaluated for their suitability for influenza virus research. Three discrete cell morphotypes were identified using light microscopy. Besides morphological features, the cell types can be distinguished by the level of expression of surface glycans recognized by peanut agglutinin (PNA). All clones were susceptible to infection by influenza viruses of different subtypes of influenza A virus (H1N1, H1N1pdm09, H3N2, H5N1) and influenza B virus, and all possessed on their surface terminally sialylated glycans with both types of glycosidic linkage (α2–3 and α2–6). The Type-1 cell lines were able to support a multicycle replication of influenza A and B viruses without help of an exogenous trypsin. In contrast, cell lines exhibiting Type-2 morphology were unable to support multicycle replication of influenza A viruses without trypsin supplementation. Western blot analysis of the hemagglutinin of H1N1 strains demonstrated that Type-2 cells were deficient in production of proteolytically activated hemagglutinin (no cleavage between HA1/HA2 was observed). HA1/HA2 cleavage of influenza B viruses in the Type-2 cells was also significantly impaired, but not completely abrogated, producing sufficient amount of activated HA to support efficient virus replication without trypsin. In contrast, all clones of Type-1 cells were able to produce proteolytically activated hemagglutinin of influenza A and B viruses. However, the growth kinetics and plaque size of influenza A viruses varied significantly in different clones. Influenza B virus also showed different plaque size, with the biggest plaque formation in the Type-2 cells, although the growth kinetics and peak infectivity titers were similar in all clones. Taken together, the study demonstrates that the population of original MDCK cells is represented by various types of cells that differ in their capacities to support replication of influenza A and B viruses.
A two-stage strategy for the construction of D-optimal experimental designs

Under the classical framework of optimal designs, it is usually assumed that the model is known for which an optimal design is derived under a given optimality criterion. In real-life applications, however, models are rarely known in advance especially when new processes are being investigated. Therefore, the optimal design derived from the classical framework may be the best design under the assumed but wrong model. In this paper, we propose and study a two-stage strategy to tackle the problem. We also introduce the concept of expected relative efficiency in order to compare the performance of the proposed two-stage designs with the classical uni-stage designs. Some open problems for future research are discussed
The economic burden of skin disease in the United States.

Abstract Background: Skin diseases and their complications are a significant burden on the nation, both in terms of acute and chronic morbidities and their related expenditures for care. Because accurately calculating the cost of skin disease has proven difficult in the past, we present here multiple comparative techniques allowing a more expanded approach to estimating the overall economic burden. Objectives: Our aims were to (1) determine the economic burden of primary diseases falling within the realm of skin disease, as defined by modern clinical disease classification schemes and (2) identify the specific contribution of each component of costs to the overall expense. Methods: Costs were taken as the sum of several factors, divided into direct and indirect health care costs. The direct costs included inpatient hospital costs, ambulatory visit costs (further divided into physician's office visits, outpatient department visits, and emergency department visits), prescription drug costs, and self-care/over-the-counter drug costs. Indirect costs were calculated as the outlay of days of work lost because of skin diseases. Results: The economic burden of skin disease in the United States is large, estimated at approximately $35.9 billion for 1997, including $19.8 billion (54%) in ambulatory care costs; $7.2 billion (20.2%) in hospital inpatient charges; $3.0 billion (8.2%) in prescription drug costs; $4.3 billion (11.7%) in over-the-counter preparations; and $1.6 billion (6.0%) in indirect costs attributable to lost workdays. Conclusions: Our determination of the economic burden of skin care in the United States surpasses past estimates several-fold, and the model presented for calculating cost of illness allows for tracking changes in national expenses for skin care in future studies. The amount of estimated resources devoted to skin disease management is far more than required to treat conditions such as urinary incontinence ($16 billion) and hypertension ($23 billion), but far less than required to treat musculoskeletal conditions ($193 billion). (J Am Acad Dermatol 2003;48:592-9.)
Interactions between cochlear implant electrode insertion depth and frequency-place mapping.

While new electrode designs allow deeper insertion and wider coverage in the cochlea, there is still considerable variation in the insertion depth of the electrode array among cochlear implant users. The present study measures speech recognition as a function of insertion depth, varying from a deep insertion of 10 electrodes at 28.8 mm to a shallow insertion of a single electrode at 7.2 mm, in four Med-El Combi 40+ users. Short insertion depths were simulated by inactivating apical electrodes. Speech recognition increased with deeper insertion, reaching an asymptotic level at 21.6 or 26.4 mm depending on the frequency-place map used. Baskent and Shannon [J. Acoust. Soc. Am. 116, 3130–3140 (2004)] showed that speech recognition by implant users was best when the acoustic input frequency was matched onto the cochlear location that normally processes that frequency range, minimizing the spectral distortions in the map. However, if an electrode array is not fully inserted into the cochlea, a matched map will ...
Raman and infrared spectra, barriers to internal rotation, vibrational assignments and ab initio calculations on 2-fluoropropane

The Raman (3500-20 cm−1) and infrared (3500-50 cm−1) spectra of gaseous and solid 2-fluoropropane, (CH3)2CFH, the corresponding trideuterated molecule, (CH3)(CD3)CFH, and heptadeuterated species, (CD3)2CFD, were recorded. Additionally, the Raman spectra of the pure liquids were recorded and qualitative depolarization values were obtained. All 27 of the normal vibrational modes were assigned for all three isotopic species based on infrared band contours, depolarization values, isotopic shifts and group frequencies. The vibrational assignment is supported by an ab initio calculation utilizing the 3-21G basis set to obtain the force constants and potential energy distribution. Additionally, ab initio calculations were carried out utilizing the 6-31G* basis set to obtain structural parameters and barriers to internal rotation. All of these results are compared with the experimentally determined values and with the corresponding results for some related molecules.
Real-time travel time prediction using particle filtering with a non-explicit state-transition model

The research presented in this paper develops a particle filter approach for the real-time short to medium-term travel time prediction using real-time and historical data. Given the challenges in defining the particle filter time update process, the proposed algorithm selects particles from a historical database and propagates particles using historical data sequences as opposed to using a state-transition model. A partial resampling strategy is then developed to address the degeneracy problem by replacing invalid or low weighted particles with historical data that provide similar data sequences to real-time traffic measurements. As a result, each particle generates a predicted travel time with a corresponding weight that represents the level of confidence in the prediction. Consequently, the prediction can produce a distribution of travel times by aggregating all weighted particles. A 95-mile freeway stretch from Richmond to Virginia Beach along I-64 and I-264 is used to test the proposed algorithm. Both the absolute and relative prediction errors using the leave-one-out cross validation concept demonstrate that the proposed method produces the least deviation from ground truth travel times, compared to instantaneous travel times, two Kalman filter algorithms and a K nearest neighbor (k-NN) method. Moreover, the maximum prediction error for the proposed method is the least of all the algorithms and maintains a stable performance for all test days. The confidence boundaries of the predicted travel times demonstrate that the proposed approach provides good accuracy in predicting travel time reliability. Lastly, the fast computation time and online processing ensure the method can be used in real-time applications.
Thoracoscopic approaches to the thoracic spine: experience with 241 surgical procedures.

INTRODUCTION: Microsurgical thoracoscopic approaches to the thoracic spine allow access to the spinal cord, spinal nerves, disc spaces, vertebral bodies, paravertebral soft tissues, and sympathetic chain with minimal invasiveness. METHODS: Between January 1994 and January 2000, 241 thoracoscopic procedures were performed: 164 thoracic sympathectomies, 60 discectomies, 5 neurogenic tumor resections, 8 corpectomies and spinal reconstructions, 2 anterior releases, and 2 biopsies. Cases were reviewed to evaluate the efficacy, surgical results, and complications of the thoracoscopic procedures. RESULTS: An adequate sympathectomy was achieved in all 164 sympathectomies. There was 100% relief of palmar and 95% relief of axillary hyperhidrosis. Reflex sympathetic dystrophy responded poorly to sympathectomy with recurrent pain. Thoracoscopic discectomy achieved complete decompression in 98% of patients. Gross total tumor resection was achieved in all five paraspinai neurogenic tumors. There was no operative mortality. Morbidity compared favorably with open surgical approaches to the thoracic spine. CONCLUSION: Thoracoscopic spinal surgery is an effective technique that provides full, direct access to the ventral thoracic spine. Its morbidity rate appears to be lower than that associated with open thoracotomy. It improves patient comfort and cosmetic results and shortens recovery. This technique has become the authors' surgical approach of choice for removing benign intrathoracic paraspinai neurogenic tumors and central herniated thoracic discs and for performing biopsies and thoracic sympathectomies, The senior author still prefers open surgical approaches for most thoracic corpectomies and spinal reconstruction procedures.
Pressure dependence of the band structure, density of states, Fermi surfaces, and optical properties of superconducting K3C60.

The electronic, the structural, and the optical properties of the fcc ${\mathrm{K}}_{3}$${\mathrm{C}}_{60}$ crystal and their dependence on isotropic pressure are studied theoretically by means of first-principles local-density calculations. The calculated equilibrium volume and the pressure coefficients are in good agreement with experimental measurements. The changes in the band structure, the density of states (DOS), the Fermi-surface topology, and the optical-absorption spectrum with pressure are analyzed in detail and compared with other recent theoretical calculations and available measurements. With an increased pressure, the DOS at the Fermi level decreases, the gap diminishes, and the bands widen and eventually merge. The change in the band structure has resulted in the merging of the absorption peaks in the optical spectrum and in the decrease of the static dielectric constant. The linear dependence of the DOS at the Fermi level due to pressure is found to have a smaller slope than that due to the expansion of the lattice by introducing different alkali-metal intercalates of varying ionic radii. The pressure dependence of the superconducting temperature in ${\mathrm{K}}_{3}$${\mathrm{C}}_{60}$ is estimated by the use of the McMillan formula and a set of optimized parameters obtained earlier in the study of ${\mathit{T}}_{\mathit{c}}$ in five alkali-metal-doped fullerites. The agreement with the measured data is not as good as that for the other alkali-metal-doped fullerites but shows the correct trend. The effective Coulomb repulsion in ${\mathrm{K}}_{3}$${\mathrm{C}}_{60}$ is also estimated and found to be small.
Semitic Morphology: Root-based or Word-based?

This issue of the journal Morphology contains papers devoted to issues in Semitic morphology. The majority of the papers are based on presentations given in a special session on Semitic morphology at the 11th International Morphology Meeting, held in Vienna in February, 2004. The core questions addressed by each article in this issue concern whether Semitic morphology is based on the consonantal root, based on the word, or based on both. These questions are of crucial importance for Semitic morphology but also for general morphology as well. The collection of papers in this issue addresses different types of evidence from a variety of Semitic languages, and provides both conclusions about Semitic morphology as well as questions for further research. The standard approach to morphological patterning in Semitic is known to most linguists as the ‘‘root-and-pattern’’ approach. Traditionally, this approach invokes lexical elements not seen in other language families, such as the consonantal root and vocalic pattern, and is based primarily on notable work in the generative framework by McCarthy (1979, 1981), in which the autosegmental model developed by Goldsmith (1976) was applied at a morphological level to explain regularities of morphophonological patterning in Semitic languages. The empirical domain of this traditional approach generally covers verbal and nominal patterns, and the nature of the autosegmental representation seemed ideal at the time to capture these patterns. Such patterns include reduplication, co-occurrence restrictions, and of course, derivational and inflectional patterns.
A Fast Implementation of a Minimum Variance Estimator for Computerized Tomography Image Reconstruction

Most present day computerized tomography (CT) systems are based on reconstruction algorithms that produce only approximate deterministic solutions of the image reconstruction problem. These algorithms yield reasonable results in cases of low measurement noise and regular measurement geometry, and are considered acceptable because they require far less computation and storage than more powerful algorithms that can yield near optimal results. However, the special geometry of the CT image reconstruction problem can be used to reduce by orders of magnitude the computation required for optimal reconstruction methods, such as the minimum variance estimator. These simplifications can make the minimum variance technique very competitive with well-known approximate techniques such as the algebraic reconstruction technique (ART) and convolution-back projection. The general minimum variance estimator for CT is first presented, and then a fast algorithm is described that uses Fourier transform techniques to implement the estimator for either fan beam or parallel beam geometries. The computational requirements of these estimators are examined and compared to other techniques. To allow further comparison with the commonly used convolution-back projection method, a representation of the fast algorithm is derived which allows its equivalent convolving function to be examined. Several examples are presented.
Business Segments and Corporate Relations with U.S. Universities

It is generally assumed that business derives important benefits from higher education and provides financial support in return. This presumes that business is relatively undifferentiated, and that corporate relations with universities are largely uniform. Using data on the governing boards and characteristics of 341 colleges and universities selected through a national sample, I show that what is called the “dominant stratum” of business, rather than business as a whole, has formed an enduring relationship with universities that are oriented toward education of the elite: the governing boards of these universities are disproportionately composed of members of the dominant stratum; universities with high proportions of dominant stratum trustees are more successful than others in raising financial support from corporations; and members of the dominant stratum take a direct role in obtaining corporate contributions. The findings imply that relations between business and higher education are structured less around business as a whole and more around a distinct segment of business.
A temperature analysis of thermostatically controlled root canal sterilizers using molten metal, glass beads, or salt

Abstract 1. A temperature analysis was done on three sterilizers using molten metal, glass beads and salt by means of the apparatus shown in Fig. 1. 2. The order of efficacy of heat conduction appears to be: molten metal, salt, glass beads. 3. Salt exhibits certain practical advantages over molten metal and glass beads for the less experienced operator. 4. A definite gradient of temperature exists between the base and surface of all sterilizers, and between the outer circumference of the well and the center of the well in sterilizers using solid heat-conducting media. 5. Substitution of salt or glass beads into wells designed for molten metal appears to be contraindicated unless an approximate temperature of 425° to 475° F. can be attained. 6. A narrow deep well is preferable to a wide shallow well when solid heat-conducting media are used in a thermostatically controlled sterilizer. 7. Instruments to be sterilized should be inserted as deep as possible near the sides of the well when sold heat-conducting media are used.
Prices, Spatial Competition, and Heterogenous Producers: An Empirical Test

Homogeneous-producer models attribute lower prices in denser markets solely to lower optimal markups. I argue here that when producers have different production costs, competition-driven selection on costs also reduces prices. This selection mechanism can be distinguished from the homogenous-producer case because it implies that higher density leads not only to lower average prices, but to declines in upper-bound prices and price dispersion as well. I find empirical support for this mechanism in the prices of ready-mixed concrete plants. I also show these findings do not simply reflect lower factor prices in dense markets, but result instead because dense-market producers are more efficient.
Impacts of Camping on Vegetation: Response and Recovery Following Acute and Chronic Disturbance

Experiments with controlled levels of recreational camping were conducted on previously undisturbed sites in two different plant communities in the subalpine zone of the Wind River Mountains, Wyoming, USA. The plant communities were coniferous forest with understory dominated by the low shrub Vaccinium scoparium and a riparian meadow of intermixed grasses and forbs, of which Deschampsia cespitosa was most abundant. Sites were camped on at intensities of either one or four nights per year, for either one (acute disturbance) or three consecutive years (chronic disturbance). Recovery was followed for three years on sites camped on for one year and for one year on sites camped on for three years. Reductions in vegetation cover and vegetation height were much more pronounced on sites in the forest than on sites in the meadow. In both plant communities, increases in vegetation impact were not proportional to increases in either years of camping or nights per year of camping. Close to the center of campsites, near-maximum levels of impact occurred after the first year of camping on forested sites and after the second year on meadow sites. Meadow sites recovered completely within a year, at the camping intensities employed in the experiments. Forest sites, even those camped on for just one night, did not recover completely within three years. Differences between acute and chronic disturbance were not pronounced.
Role of surface states in contributing to p-type carrier concentration of vacuum deposited thin germanium films

Germanium films were deposited by evaporation on to heated single crystal calcium fluoride substrates, which were cleaved either in air or inside the vacuum system. Results indicate that structural defects and impurities probably are not responsible for the high concentration of acceptors (≈ 1018/cm3) typically found in deposited germanium films. It is therefore believed that surface states and the associated space charge layer completely dominate the electrical characteristics of thin (< 3000 A) deposited germanium films.
The effect of retained intramedullary nails on tibial bone mineral density

Abstract Background Intramedullary nailing has become a standard treatment for adult tibial shaft fractures. Retained intramedullary nails have been associated with stress shielding, although their long-term effect on decreasing tibial bone mineral density is currently unclear. The purpose of this study was to determine if retained tibial intramedullary nails decrease tibial mineral density in patients with successfully treated fractures. Methods Patients treated with statically locked intramedullary nails for isolated, unilateral tibia shaft fractures were studied. Inclusion required that fracture had healed radiographically and that the patient returned to the pre-injury activity level. Data on patient demographic, fracture type, surgical technique, implant, and post-operative functional status were tabulated. Dual energy X-ray absorptiometry was used to measure bone mineral density in selected regions of the affected tibia and the contralateral intact tibia. Image reconstruction software was employed to ensure symmetry of the studied regions. Findings Twenty patients (mean age 43; range 22–77 years) were studied at a mean of 29 months (range 5–60 months) following intramedullary nailing. There was statistically significant reduction of mean bone mineral density in tibiae with retained intramedullary nails (1.02 g/cm2 versus 1.06 g/cm2; P = 0.04). A significantly greater decrease in bone mineral density was detected in the reamed versus nonreamed tibiae (–7% versus +6%, respectively; P Interpretation The present study demonstrates a small, but statistically significant overall bone mineral density decrease in healed tibiae with retained nails. Intramedullary reaming appears to be a factor potentiating the reduction of tibia bone mineral density in long-term nail retention.
Perfluorotetramethylenesulfur difluoride and its derivatives. Perfluoro-1,3-dithietane octafluoride and perfluoro-1,4-dithiane octafluoride

Abstract The fluorination of perfluorotetramethylene sulfide with chlorine monofluoride under controlled conditions results in the formation of both sulfur(IV) and sulfur(VI) compounds as main products. While perfluorotetramethylenesulfur tetrafluoride is very stable to thermolysis and to chemical attack, the hydrolysis of the novel perfluorotetramethylenesulfur difluoride affords perfluorotetramethylene sulfoxide, and its pyrolysis gives perfluro(di-n-butyl)disulfide. Chlorine monofluoride converts perfluorotetramethylene sulfoxide to perfluorotetramethyl-enesulfur oxyfluoride, and perfluorotetramethylene sulfone is obtained quantitatively as a decomposition product in contact with Pyrex glass. Perfluoro-1,3-dithietane octafluoride and perfluoro-1,4-dithiane octafluoride are also formed by the reaction of corresponding perfluorocyclic sulfides with CIF at ambient temperature. Infrared, mass and 19F NMR spectroscopic as well as thermodynamic data are reported.
Retribution, deterrence, and organ donation.

Caplan (2011) argues that there are both moral and practical concerns that make donations from prisoners an unlikely solution to the problem of organ shortage. One of the moral concerns is that har...
The application of physiologically based pharmacokinetic/ pharmacodynamic (PBPK/PD) modeling to understanding the mechanism of action of hazardous stances

Much of toxicology research is focused on elucidating the nature of the mechanisms through which various xenobiotics exert their toxic effects. The central issue in extrapolating laboratory experiments to the human situation is whether mechanisms which are operative in laboratory animals are similar to mechanisms operating in humans. The underlying assumption is that understanding mechanisms permits rational extrapolation between species, across routes of exposure, or from high to low doses. There are two general classes of mechanisms of action. First, there are the mechanisms that result in the translation of an exposure concentration to the effective dose at the target site. The mechanisms that are operative at a pharmacokinetic level include those that are physiologically driven and those that are metabolically based. Second are mechanisms through which the dose at the target site elicits the ultimate adverse response. These are pharmacodynamic in nature and refer to the action of the effective dose at the target site. Altered gene regulation, cytotoxicity, and cell proliferation are examples of processes involving potential adverse effects at the target site. A quantitative understanding of the mechanisms involved in going from exposure to dose and dose to response can aid in answering the question of whether or not these mechanisms in animals and humans are similar or different.
DISTRIBUTION AMONG THE γ-GLOBULIN MOLECULES OF DIFFERENT GENETICALLY DETERMINED ANTIGENIC SPECIFICITIES IN THE GM SYSTEM

Isolated myeloma proteins and anti-Rh antibodies were utilized for determination of the distribution among the γ-globulin molecules of various Gm(b) and Gm(f) determinants. All of these genetic factors are as a rule inherited together in Caucasians, but not in other races. The Gm(b) determinants, except (b2), were found together in the same Caucasian myeloma globulins of the Vi H chain group, which never carried Gm(f) or (b2). The Gm(f) and (b2) determinants were found together in other myeloma globulins, of the We group. Anti-Rh antibody molecules appeared to be similar to myeloma molecules in these respects. A few myeloma proteins and anti-Rh antibodies were encountered which reacted with some but not other anti-Gm(b) or anti-Gm(f) reagents; the only available Vi type myeloma protein from a Negro, specifically lacked the Gm(b3) factor. The observations might be explained by the following hypothesis: In Caucasians with the common Gmf Gmb gene complex the Gm(b) antigenic determinants, except (b2), co-occur in certain molecules, which contain a polypeptide chain determined by the Gmb gene; the Gm(f) and (b2) determinants co-occur in other molecules, which contain a polypeptide chain determined by the Gmf gene. Individuals that lack some Gm(b) or Gm(f) determinants most likely have a gene partly different from Gmb or Gmf . The value of studies with myeloma proteins from individuals of different racial groups was apparent from this study. One myeloma protein from a Chinese was unique in that it was both Gm(a+) and Gm(f+).
Enhancing the Thermal Stability of Polythiophene:Fullerene Solar Cells by Decreasing Effective Polymer Regioregularity

Regioregularity has been shown to be an important aspect for the properties of poly(3-hexylthiophene) both in the pristine material and in bulk heterojunction photovoltaics with the fullerene derivative PCBM. Here we present a straightforward method to adjust the effective regioregularity of poly(3-hexylthiophene) by introducing 3,4-dihexylthiophene into the polymer chain. By investigating bulk heterojunction morphology and photovoltaic performance upon annealing, we observe that polythiophene with 91% regioregularity maintains equivalent electronic properties but forms a more thermally stable interpenetrating network with PCBM than polythiophene with regioregularity >96%.
Protein Folding Studies in Vivo with a Bacteriophage T4 Expression-Packaging-Processing Vector That Delivers Encapsidated Fusion Proteins into Bacteria

A cloned phage T4 gene which expresses the nonessential capsid scaffold protein IPIII was modified to permit construction and packaging of protein fusions within the capsid. IPIII deletion phage packaged IPIII-beta-galactosidase, IPIII-beta-globin, and IPIII-beta-globin-beta-galactosidase fusion proteins; the latter protein fusion was specifically processed by the T4 gene 21 head morphogenetic proteinase in vivo at a consensus leu(ile)-P1-glu* cleavage site to regenerate beta-galactosidase. Phage inject IPIII-beta-galactosidase protein into bacteria, but less activity is recovered in infections of Escherichia coli dnaK or groEL mutants, suggesting that these host molecular chaperones are required for beta-galactosidase intracellular folding. This expression-packaging-processing (EPP) vector directs protein fusions into capsids for easy detection and purification and permits study of protein delivery and folding in bacteria.
230Th-238U disequilibrium systematics in oceanic tholeiites from 21°N on the East Pacific Rise

Significant disequilibrium occurs between ^(230)Th and its parent, ^(238)U, in a suite of fresh basalt glasses from the RISE Project study area at 21°N on the East Pacific Rise. The (^(230)Th/^(232)Th) activity ratios observed for eight of nine samples from the crest of the axis at this site are constant within analytical uncertainty, with a value of 1.22. This observed homogeneity of (^(230)Th/^(232)Th) has two possible interpretations. First, the measured (^(230)Th/^(232)Th) can be considered to indicate a mantle-source for the RISE basalts with Th/U of 2.5. This interpretation, however, conflicts with the proposed correlation between (^(230)Th/^(232)Th) and ^(87)Sr/^(86)Sr [1] which predicts that (^(230)Th/^(232)Th) should equal 1.33 at the RISE site. A second possible interpretation is that radioactive decay of ^(230)Th, in the basalts themselves or in a magma chamber, has decreased (^(230)Th/^(232)Th) from 1.33 to the observed values. The required time span is 11,000 to > 100,000 years. However, petrologic arguments rule against long residence time in a magma chamber, and the spreading rate of this section of the East Pacific Rise (6 cm/yr) predicts that the maximum age for axis basalts is 27,000 years. Both interpretations of the measured (^(230)Th/^(232)Th) imply a low Th/U ratio for the RISE basalt source and suggest that the MORB source at this location is depleted in Th with respect to U relative to primitive mantle or bulk earth. In spite of their constant (^(230)Th/^(232)Th), the basalts from 21°N have wide ranges of measured Th/U and thorium and uranium concentrations, in apparent conflict with the common assumption that these two elements have very small, similar crystal-liquid partition coefficients. Participation of an accessory phase with high Th and U concentrations during partial melting or fractional crystallization appears to be required to explain this anomaly. Major and other trace element compositions provide more information about petrogenetic processes. Although fractional crystallization can explain the variations in major element composition, a more complex process such as continuous melting is required to account for the observed trends in trace element compositions. In addition to its use as a tracer, the ^(230)Th-^(238)U disequilibrium technique is capable of putting some constraints on the timing of fractionation events, and it may eventually lead to a method for dating very young mid-ocean ridge basalts.