cssi/SciSciGPT-SciSciNet huggingface dataset:
Nucleophilic Participation in the Transition State for Human Thymidine Phosphorylase

Recombinant human thymidine phosphorylase catalyzes the reaction of arsenate with thymidine to form thymine and 2-deoxyribose 1-arsenate, which rapidly decomposes to 2-deoxyribose and inorganic arsenate. The transition-state structure of this reaction was determined using kinetic isotope effect analysis followed by computer modeling. Experimental kinetic isotope effects were determined at physiological pH and 37 °C. The extent of forward commitment to catalysis was determined by pulse-chase experiments to be 0.70%. The intrinsic kinetic isotope effects for [1‘-3H]-, [2‘R-3H]-, [2‘S-3H]-, [4‘-3H]-, [5‘-3H]-, [1‘-14C]-, and [1-15N]-thymidines were determined to be 0.989 ± 0.002, 0.974 ± 0.002, 1.036 ± 0.002, 1.020 ± 0.003, 1.061 ± 0.003, 1.139 ± 0.005, and 1.022 ± 0.005, respectively. A computer-generated model, based on density functional electronic structure calculations, was fit to the experimental isotope effect. The structure of the transition state confirms that human thymidine phosphorylase proceeds ...
The effect of visual deprivation on gastrointestinal ulceration.

Abstract Visual deprivation reduced the incidence of perforated ulcers and increased the survival time of dogs subjected to the Exalto-Mann-Williamson ulcer and reduced both the time of onset and the degree of ulceration in rats subjected either to the Shay ulcer or to the restraint-cold ulcer procedure.
A semiempirical linear model of indirect, flat-panel x-ray detectors

Purpose: It is important to understand signal and noise transfer in the indirect, flat-panel x-ray detector when developing and optimizing imaging systems. For optimization where simulating images is necessary, this study introduces a semiempirical model to simulate projection images with user-defined x-ray fluence interaction. Methods: The signal and noise transfer in the indirect, flat-panel x-ray detectors is characterized by statistics consistent with energy-integration of x-ray photons. For an incident x-ray spectrum, x-ray photons are attenuated and absorbed in the x-ray scintillator to produce light photons, which are coupled to photodiodes for signal readout. The signal mean and variance are linearly related to the energy-integrated x-ray spectrum by empirically determined factors. With the known first- and second-order statistics, images can be simulated by incorporating multipixel signal statistics and the modulation transfer function of the imaging system. To estimate the semiempirical input to this model, 500 projection images (using an indirect, flat-panel x-ray detector in the breast CT system) were acquired with 50–100 kilovolt (kV) x-ray spectra filtered with 0.1-mm tin (Sn), 0.2-mm copper (Cu), 1.5-mm aluminum (Al), or 0.05-mm silver (Ag). The signal mean and variance of each detector element and the noise power spectra (NPS) were calculated and incorporated into this model for accuracy. Additionally, the modulation transfer function of the detector system was physically measured and incorporated in the image simulation steps. For validation purposes, simulated and measured projection images of air scans were compared using 40 kV/0.1-mm Sn, 65 kV/0.2-mm Cu, 85 kV/1.5-mm Al, and 95 kV/0.05-mm Ag. Results: The linear relationship between the measured signal statistics and the energy-integrated x-ray spectrum was confirmed and incorporated into the model. The signal mean and variance factors were linearly related to kV for each filter material (r2 of signal mean to kV: 0.91, 0.93, 0.86, and 0.99 for 0.1-mm Sn, 0.2-mm Cu, 1.5-mm Al, and 0.05-mm Ag, respectively; r2 of signal variance to kV: 0.99 for all four filters). The comparison of the signal and noise (mean, variance, and NPS) between the simulated and measured air scan images suggested that this model was reasonable in predicting accurate signal statistics of air scan images using absolute percent error. Overall, the model was found to be accurate in estimating signal statistics and spatial correlation between the detector elements of the images acquired with indirect, flat-panel x-ray detectors. Conclusions: The semiempirical linear model of the indirect, flat-panel x-ray detectors was described and validated with images of air scans. The model was found to be a useful tool in understanding the signal and noise transfer within indirect, flat-panel x-ray detector systems.
Bibliography for Work in Travel Studies

The Library Series of the peer-reviewed, full-text, and open-access quarterly in the humanities and the social sciences CLCWeb: Comparative Literature and Culture publishes scholarship in the humanities and social sciences following tenets of the discipline of comparative literature and the field of cultural studies designated as "comparative cultural studies." Publications in the Library Series are 1) articles, 2) books, 3) bibliographies, 4) resources, and 5) documents. Contact:
Natural convection from horizontal cylinders in interacting flow fields

Abstract Natural convection heat transfer from single and double rows of closely spaced isothermal heated cylinders was investigated numerically for both laminar and turbulent cases. A sufficiently large number of cylinders are considered in each row such that a symmetry unit can be considered for the analysis. The numerical scheme involves the use of a cylindrical network of nodes in the vicinity of the cylinder with a Cartesian mesh covering the remainder of the flow domain. The k−e turbulence model has been applied to obtain the results for the turbulent flow predictions. Effects of varying the cylinder spacings in the horizontal direction are also considered. The results are of direct use in electrical packaging, solar heating and storing technology, nuclear reactor safety and waste disposal, among others.
A simple automatic derivative evaluation program

A procedure for automatic evaluation of total/partial derivatives of arbitrary algebraic functions is presented. The technique permits computation of numerical values of derivatives without developing analytical expressions for the derivatives. The key to the method is the decomposition of the given function, by introduction of intermediate variables, into a series of elementary functional steps. A library of elementary function subroutines is provided for the automatic evaluation and differentiation of these new variables. The final step in this process produces the desired function's derivative.The main feature of this approach is its simplicity. It can be used as a quick-reaction tool where the derivation of analytical derivatives is laborious and also as a debugging tool for programs which contain derivatives.
Static shear correction factor for laminated rectangular beams

Most practical analyses of laminated composite beams, particularly rectangular sections used in civil structures, are based on first order shear deformation theories (FSDT), which generally require shear correction factors to account for shear stiffness and transverse shear stress. Using an energy equivalence principle, a general expression for the shear correction factor of laminated rectangular beams with arbitrary lay-up configurations is derived in this paper. A convenient algebraic form of the solution is presented and validated with existing results for composite beams and plates. An example is given to illustrate the use of the present formulation, and a parametric study is conducted to evaluate the effect of number of layers, elastic moduli ratio, and fiber-angle orientation on the shear correction factor for various laminates.
The Citation Landscape of Scholarly Literature in LGBT Studies: A Snapshot for Subject Librarians

This paper reports the results of a citation analysis of the scholarly literature of LGBT Studies. EBSCO’s LGBT Life database was used to gather a sample of 4,321 citations from core scholarly journals in the field of LGBT Studies, covering the time period 1974 to 2010. The analysis reveals that, although LGBT Studies as an area of scholarship emerged from the gay rights activist movement of the 1960s and 1970s, the field’s literature appears to be firmly rooted in the mainstream academic literature rather than in popular publications or community and activist periodicals. However, the field has a very high rate of cross-disciplinary citation and cites particularly heavily from medical journals and books. In addition to illuminating the citation characteristics of LGBT Studies, this paper presents lists of highly cited books and journals that should prove useful for subject librarians supporting LGBT Studies programs.
L-glutamate blockade of transmission at the giant synapse of the squid stellate ganglion.

The addition of L-glutamate to the perfusion fluid of the squid stellate ganglion in concentrations from 5–100 mM led to a marked depression of the maximum rate of the rise of the PSP but never caused a detectable change in the membrane potential or conductance. In solutions containing 5 mM of glutamate, the reduction in the maximum rate of rise of the PSP occurred slowly and was incomplete after 60 min, however, in high concentrations the decline was much more rapid and the PSP disappeared completely. In glutamate free sea water the PSP rapidly reappeared and recovered its initial rate of rise in about 30 min. Since glutamate depression can be attributed to desensitization this result is consistent with the view that the transmitter substance is either glutamate or a chemically related compound. In the presence of 100–50 mM of magnesium the synapse is insensitive to 5 mM of glutamate and 10 mM is much less effective, perhaps as a result of magnesium glutamate binding. Thiosemicarbazide, an inhibitor of the enzyme system, glutamate decarboxylase, failed to cause an increase in the amplitude or duration of the PSP or an increase in potency of exogenous glutamate.
Personality Measurement and Assessment in Large Panel Surveys

Personality tests are being added to large panel studies with increasing regularity, such as the Health and Retirement Study (HRS). To facilitate the inclusion and interpretation of these tests, we provide some general background on personality psychology, personality assessment, and the validity of personality tests. In this review, we provide background on definitions of personality, the strengths and weaknesses of the self-report approaches to personality testing typically used in large panel studies, and the validity of personality tests for three outcomes: genetics, income, and health. We conclude with recommendations on how to improve personality assessment in future panel studies.
A High Impact Practice that Works: Connecting Mentors From the Professional Community to Teacher Education Students

A high impact mentoring program at a community college connected professionals from the special education and early intervention fields with small groups of teacher education students. Two federal grants from U.S. Department of Education funded tuition scholarships and mentoring for 76 Special Education students and 78 Early Childhood Education/Early Intervention students in associate degree programs. The mentor programs consisted of individual monitoring by project staff, consistent contact with a mentor from the professional community and with other students in mentor groups, and structured monthly dinner meetings. Students who participated in the mentoring programs showed increased persistence and higher grade point average when compared with the general population of similar majors. Within each grant-funded population, students who showed low participation in the mentor programming presented lower retention rates and lower GPA than grant-funded students who took full advantage of the mentoring program.
The Soil Conservation Service's interest in Geographic Information Systems

Abstract The Soil Conservation Service (SCS) has used two computer mapping and analysis systems in in-house projects: one polygon, one grid. Both have shown strengths and weaknesses. Cooperative efforts with other organizations have also been useful in defining the characteristics of the more efficient system which SCS hopes to develop. Users inside and outside SCS could benefit.
Elastic and ultimate behavior of amorphous polymer networks

Abstract This paper proposes that physically cross-linked amorphous polymer networks can successfully be treated a s reinforced composite solids. The suggested model is based on observations in three different areas of investigation: on the composite solid approach of oriented polymers, on the time-dependent fracture strength of polymer networks, and on the kinetics of chain breakage (free radical formation) in stressed polymers as observed by electron spin resonance (ESR).
Studies on the Antioxidative Activities of Hsian-tsao (Mesona procumbens Hemsl) Leaf Gum

This study aimed at evaluating the antioxidative activity of crude hsian-tsao leaf gum extracted by sodium bicarbonate solutions and precipitated by 70% ethanol. The antioxidative activities, including the radical-scavenging effects, Fe(2+)-chelating ability, and reducing power as well as the inhibition of FeSO(4)-H(2)O(2)-induced malondialdehyde formation in rat tissue homogenate were studied in vitro. It was found that the antioxidative effect provided by hsian-tsao leaf gum was strongly concentration dependent. In general, the antioxidative activity increased with increasing gum concentration, to a certain extent, and then leveled off with further increase in gum concentration. A concentrtaion-dependent kinetics for the rate of change in antioxidative activity was proposed. The antioxidative activity constant (k) and the half-inhibition concentration (IC(50)) for each antioxidative reaction studied were calculated. From a comparison of the IC(50) values for different antioxidative reactions, it seemed that hsian-tsao leaf gum was more effective in scavenging superoxide radicals than chelating Fe(2+) or scavenging alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) radicals. As compared to the commercial antioxidants, hsian-tsao leaf gum showed less scavenging effect on the DPPH radical and reducing power but better superoxide radical-scavenging effect and Fe(2+)-chelating ability than alpha-tocopherol and BHT.
Achievement on a Test of Specific Coding Skills Contrasted with Achievement Global Tests of Reading Skills

A test was constructed to measure coding ability --- skill in recognizing classes of words grouped by their phonic structure and the grapheme-phoneme combinations they contained. When the test was administered to low and middle group readers and to children in a learning disability program, marked differences in mastery of these skills appeared among children who had similar word recognition scores on standardized tests. The ability to read any or most words incorporating particular graphemephoneme combinations within a particular phonic structure requires mastery of the coding process and represents a more complex skill than the ability to recognize by sight a few words incorporating these same phonic elements. The experimental test 1) identified children with possible coding process disabilities common among the learning disability population, 2) indicated which particular classes of phonemes a child had not yet learned to use in recognizing words, and 3) proved more useful than standardized global test...
Nonprolapsing Left Atrial Tumor: The M-Mode Echocardiographic Diagnosis

We report the echocardiographic features of a patient with a nonprolapsing left atrial tumor. By using proper gain or reject, left atrial echoes due to tumor can be differentiated from recording artifact produced by improper technique.
Mycoplasma bovoculi—Augmented bovine natural killer activity

The effect of conjunctival Mycoplasma bovoculi infection on local and systemic natural killer activity was studied in cattle. A standard in vitro assay against the mouse tumor cell line, YAC-1, was used to measure increases in effector cell activity. Local responses in the eye were investigated by examination of stained exfoliative conjunctival cells and tissue biopsies. An increase in systemic cytolytic activity was seen in infected calves, and maximal values were observed on the second day post infection (DPI). An elevation in the number of large granular lymphocytes was noted in the conjunctival samples, and maximal numbers were again observed at 2 days post infection. It is proposed that natural killer cell activity may play a role in the initial host responses of cattle to M. bovoculi infection.
The role of basin-scale transgression and sediment compaction in stratiform copper mineralization: implications from White Pine, Michigan, USA

Abstract We present a paleohydrologic model of stratiform copper mineralization in the Keweenawan Midcontinent Rift System. We attribute regional-scale mineralization in the basal facies of the transgressive Nonesuch Formation to compaction of the subjacent fluvial Copper Harbor Formation in response to deposition of the superjacent fluvial Freda Formation. The transgressive sequence focused compaction-driven discharge of cupriferous brines in the Copper Harbor Formation to the basin margins, where leakage into the overlying Nonesuch Formation drove redox-controlled copper precipitation. Intense fluid focusing atop a basement high formed the White Pine ore body. The timing of this simulated event is consistent with the inferred timing of stratiform mineralization. Our model satisfies mass-balance constraints at White Pine for a geologically plausible range of permeabilities and copper concentrations.
Distinct TLR- and NLR-Mediated Transcriptional Responses to an Intracellular Pathogen

How the innate immune system tailors specific responses to diverse microbial infections is not well understood. Cells use a limited number of host receptors and signaling pathways to both discriminate among extracellular and intracellular microbes, and also to generate responses commensurate to each threat. Here, we have addressed these questions by using DNA microarrays to monitor the macrophage transcriptional response to the intracellular bacterial pathogen Listeria monocytogenes. By utilizing combinations of host and bacterial mutants, we have defined the host transcriptional responses to vacuolar and cytosolic bacteria. These compartment-specific host responses induced significantly different sets of target genes, despite activating similar transcription factors. Vacuolar signaling was entirely MyD88-dependent, and induced the transcription of pro-inflammatory cytokines. The IRF3-dependent cytosolic response induced a distinct set of target genes, including IFNbeta. Many of these cytosolic response genes were induced by secreted cytokines, so we further identified those host genes induced independent of secondary signaling. The host response to cytosolic bacteria was reconstituted by the cytosolic delivery of L. monocytogenes genomic DNA, but we observed an amplification of this response by NOD2 signaling in response to MDP. Correspondingly, the induction of IFNbeta was reduced in nod2-/- macrophages during infection with either L. monocytogenes or Mycobacterium tuberculosis. Combinatorial control of IFNbeta induction by recognition of both DNA and MDP may highlight a mechanism by which the innate immune system integrates the responses to multiple ligands presented in the cytosol by intracellular pathogens.
Detection of new-onset choroidal neovascularization.

Purpose of reviewTo highlight the most common methods that are used to detect new-onset choroidal neovascularization (CNV) as a result of age-related macular degeneration (AMD).Recent findingsNumerous modalities are available to try to detect CNV. Amsler grid testing, preferential hyperacuity perime
The U.S. national innovation system: Origins and prospects for change

In recent years, the concept of “national innovation systems” has attained considerable currency and interest. Although a precise definition of a national innovation system is difficult, analyses of the Japanese and U.S. national innovation systems have implicitly defined them as the array of public and private institutions and organizations within an economy that fund and perform RD Nelson, 1993). Interest in national innovation systems stems in part from a growing acknowledgment of the contributions to national economic welfare of superior performance in the commercialization and adoption of new technologies. This awareness in turn has been heightened by the innovative and economic strength of postwar Japan.
Effects of ethnicity and nephropathy on lower-extremity amputation risk among diabetic veterans.

OBJECTIVE —To describe ethnic differences in the risk of amputation in diabetic patients with diabetic nephropathy. RESEARCH DESIGN AND METHODS —A retrospective cohort study was conducted on a national cohort of diabetic patients who received primary care within the Veterans Affairs (VA) Health Care System. Hospitalizations for lower-limb amputations were established by ICD-9-CM procedure codes. Relative risk of amputation in diabetic patients with and without diabetic nephropathy was determined using Cox proportional hazard modeling for unadjusted and adjusted models. RESULTS —Of the 429,918 subjects identified with diabetes (mean age 64 ± 11 years, 97.4% male), 3,289 individuals were determined to have had a lower-limb amputation during the study period. Compared with diabetic patients without amputations, amputees were on average older, more likely to belong to a minority group, and were more likely to have received treatment for more comorbid conditions. Asians were more likely to have toe amputations compared with whites or other ethnicities, while Native Americans were more likely to have below-the-knee amputations. Native Americans had the highest risk of amputation (RR 1.74, 95% CI 1.39–2.18), followed by African Americans (RR 1.41, 95% CI 1.34–1.48) and Hispanics (RR 1.28, 95% CI 1.20–1.38) compared with whites. The presence of diabetic nephropathy increased the risk of amputation threefold in all groups. Asian subjects with diabetes had the lowest adjusted relative risk of amputation (RR 0.31, 95% CI 0.19–0.50). CONCLUSIONS —Among diabetic patients, certain ethnic minority individuals have an increased risk of lower-extremity amputation compared with whites. Presence of diabetic nephropathy further increases this risk.
Influence of air quality model resolution on uncertainty associated with health impacts

Abstract. We use regional air quality modeling to evaluate the impact of model resolution on uncertainty associated with the human health benefits resulting from proposed air quality regulations. Using a regional photochemical model (CAMx), we ran a modeling episode with meteorological inputs simulating conditions as they occurred during August through September 2006 (a period representative of conditions leading to high ozone), and two emissions inventories (a 2006 base case and a 2018 proposed control scenario, both for Houston, Texas) at 36, 12, 4 and 2 km resolution. The base case model performance was evaluated for each resolution against daily maximum 8-h averaged ozone measured at monitoring stations. Results from each resolution were more similar to each other than they were to measured values. Population-weighted ozone concentrations were calculated for each resolution and applied to concentration response functions (with 95% confidence intervals) to estimate the health impacts of modeled ozone reduction from the base case to the control scenario. We found that estimated avoided mortalities were not significantly different between the 2, 4 and 12 km resolution runs, but the 36 km resolution may over-predict some potential health impacts. Given the cost/benefit analysis requirements motivated by Executive Order 12866 as it applies to the Clean Air Act, the uncertainty associated with human health impacts and therefore the results reported in this study, we conclude that health impacts calculated from population weighted ozone concentrations obtained using regional photochemical models at 36 km resolution fall within the range of values obtained using fine (12 km or finer) resolution modeling. However, in some cases, 36 km resolution may not be fine enough to statistically replicate the results achieved using 2, 4 or 12 km resolution. On average, when modeling at 36 km resolution, an estimated 5 deaths per week during the May through September ozone season are avoided because of ozone reductions resulting from the proposed emissions reductions (95% confidence interval was 2–8). When modeling at 2, 4 or 12 km finer scale resolution, on average 4 deaths are avoided due to the same reductions (95% confidence interval was 1–7). Study results show that ozone modeling at a resolution finer than 12 km is unlikely to reduce uncertainty in benefits analysis for this specific region. We suggest that 12 km resolution may be appropriate for uncertainty analyses of health impacts due to ozone control scenarios, in areas with similar chemistry, meteorology and population density, but that resolution requirements should be assessed on a case-by-case basis and revised as confidence intervals for concentration-response functions are updated.
Intimacy and Belonging The Association between Sexual Activity and Depression among Older Adults

There is a paucity of systematic analysis of the relation between sexual activity and mental health. To address this gap, we ask whether sexual activity associates with lower levels of depression a...
La discriminación institucional de vendedoras ambulantes: los retos de una «pobre» madre pobre trabajando en la calle

Las circunstancias particulares de mujeres que se dedican a la venta ambulante, su preferencia por el trabajo en el sector informal como vendedoras ambulantes y el ejercicio de la maternidad en una situacion de calle, no han sido discutidas a fondo como parte del contexto urbano de Honduras. Este ensayo se adentra en la cuestion de como el oficio de vendedora ambulante encaja en la experiencia de vida de las mujeres pobres, madres solas o acompanadas en una ciudad atravesada por la inseguridad economica y la exclusion social. De igual manera, se evalua lo que significa ser madre y vendedora ambulante para dos grupos de mujeres —trece entrevistadas— que participaron en la investigacion de campo que precedio el estudio, del cual se deriva este trabajo que intenta dar a conocer algunas de las justificaciones de su permanencia en el oficio que amenaza directamente su estatus de madres y de trabajadoras, empezando por situar el origen de los enfrentamientos entre estas mujeres y el Estado, y la consiguiente discriminacion institucional que enfrentan como madres trabajadoras. Mencionare ejemplos de dos entidades publicas—el Instituto Nacional de la Ninez y la Familia, IHNFA, y el gobierno municipal capitalino— que activamente ejercen la discriminacion institucional. Este ensayo se enfoca, particularmente, en la estigmatizacion de lo que hoy es predominantemente un espacio laboral de mujeres en America Latina dentro del sector informal: la venta ambulante. Se sugiere que estas mujeres retan y renegocian las mismas normas sociales y culturales que estructuralmente e institucionalmente las han mantenido marginadas y dentro del sector laboral donde se encuentran.
Effects of Laparoscopic Lavage on Adhesion Formation and Peritoneum in an Animal Model of Pelvic Inflammatory Disease

Abstract Study Objectives To develop an animal model of pelvic inflammatory disease (PID) that simulates intraluminal tubal damage and adhesion formation seen in human PID, and to evaluate peritoneal effects of laparoscopic lavage with 1% povidone-iodine, 0.5% povidone-iodine, and 0.05% chlorhexidine gluconate solutions. Design Prospective, randomized, controlled study (Canadian Task Force classification I). Setting Animal research operating room facility. Subjects Forty-five 1-year-old Pasteurella-free New Zealand white rabbits. Intervention Laparoscopy with instillation of one of five lavage solutions after bacterial inoculation with Neisseria gonorrhoeae, Bacteroides fragilis, Escherichia coli, and Peptococcus niger. Measurements and Main Results Histologic evaluation revealed significantly more peritoneal inflammation after lavage with all three solutions than after no lavage or lavage with normal saline. Gross adhesion formation was visible in only one rabbit after lavage with normal saline. One animal having lavage with 1% povidone-iodine died immediately after injection for sedation before laparoscopic lavage, and was not included in the final results. Conclusion Bacterial inoculation using an intrauterine insemination catheter did not produce clinical adhesions in 43 of 44 rabbits. Histologic evaluation revealed significantly more peritoneal inflammation in the lavage with povidone-iodine and chlorhexidine gluconate compared with no lavage or lavage with normal saline.
Dynamic Pricing of New Services in Subscription Markets

We analyze the dynamic price discrimination strategies of a monopolist who offers new services on a subscription basis. Access to customers' subscription histories permits the monopolist to design pricing policies that can be based on customers' past purchase behavior, and on the time period in which they made their purchases. Uncertainty regarding the value of new features, and heterogeneity in consumers' valuation for existing features, creates inter-temporal incentives that influence both profits and the rate of adoption of new technology. We find that the comparison of pricing regimes critically depends on whether the monopolist finds it optimal to encourage all consumers to adopt the new technology early. The pricing regimes differ only when the prior heterogeneity in consumer valuation for the existing features is relatively large, in which case the monopolist finds it optimal to serve only the part of the population of consumers that has a relatively high valuation. The monopolist can improve his profits by committing to ignore consumer past behavior, and to vary prices based only on the time period. If a stronger commitment to never utilize any price discrimination is feasible, the profits of the monopolist are even higher. However, the “First Best” outcome cannot be achieved, because it requires the monopolist to discriminate in favor of returning customers, by offering them lower prices than it offers to new customers. We also investigate the effect of positive correlation between the consumer valuations for the existing and the new features of the technology. We find that, as the correlation increases, the gap in profits among the various regimes narrows, while the ranking of the regimes remains the same. In particular, with perfect correlation, time inconsistency issues that arise due to lack of commitment disappear completely for all regimes, and the “First Best” outcome is attainable
The financial capacity of nonprofit hospitals.

The nations teaching hospitals are highly regarded, complex enterprises, but the public knows very little about their operations and their funding. Recently, Nancy Kane of the Harvard School of Public Health, under contract to Bostons commissioner of health and hospitals, prepared a report that was critical of the city's private teaching hospitals in a variety of ways. In an effort to illuminate our readers about the matters at issue, we invited Kane to prepare a brief discussion of those matters. Following Kanes essay is a report that represents the collective response of seven Boston teaching hospitals to the original Kane report released in May 1993.
Relative Energies of Tilt Boundaries in Aluminum Oxide

Aluminum oxide relative grain boundary energy and surface diffusion coefficient, considering thermal grooving of bicrystals with symmetrical tilt boundaries
Contouring buttock reconstruction after sacrococcygeal teratoma resection

Abstract Purpose Massive sacrococcygeal teratomas are typically resected and closed in a "chevron" fashion. The resultant scar may leave protuberant "dog ears" and extend across and below the infragluteal creases down onto the posterior thighs, causing undesirable buttock deformity. Given the redundant skin often available, the authors sought to develop a closure technique to minimize deformity and unpleasant scars. Methods At the time of resection of 2 sacrococcygeal teratomas, attention was directed to minimizing redundant skin, restoring normal buttock contour, and avoiding scars crossing the infragluteal crease. After properly securing the anal location, serial polygonal skin excisions were performed, working the excess tissue centrally rather than peripherally, leaving 2 right-angled scars on each buttock. Results Each infant underwent successful reconstruction with a normal buttock contour without redundancy. All scars on the buttocks can be easily covered by bathing attire. Conclusions The excess skin expanded by large sacrococcygeal teratomas affords an opportunity to apply straightforward tissue rearrangement principles to reconstruct the buttocks with a normal contour and hidden scars.
Design and Synthesis of Isosteviol Triazole Conjugates for Cancer Therapy

One of the keys for successfully developing drugs against the broad spectrum of cancer cell types is structural diversity. In the current study, we focused on a family of isosteviol derivatives as potential novel antitumor agents. Isosteviol is a tetracyclic diterpenoid obtained by acid hydrolysis of steviol glycoside extracts isolated from abundant Stevia rebaudiana plants. In this work, we have designed and synthesized a panel of isosteviol triazole conjugates using "click" chemistry methodology. Evaluation of these compounds against a series of cancer cell lines derived from primary and metastatic tumors demonstrated that these conjugates exhibit cytotoxic activities with IC50 in the low μM range. In addition, their anti-proliferative activities are cancer cell type specific. Taken together, our studies underscore the importance of structural diversity in achieving cancer cell type specific drug development.
Nuclear targeting determinants of the phage P1 Cre DNA recombinase

The Cre DNA recombinase of bacteriophage P1 has become a useful tool for genomic manipulation in mice and other eukaryotes. Because Cre is of prokaryotic origin, the 38 kDa protein has been presumed to gain access to the eukaryotic nucleus simply because it is sufficiently small to pass through the nuclear pore by passive diffusion. Instead, we show here that Cre carries nuclear targeting determinants that efficiently direct Cre entry into the nucleus of mammalian cells. Fusions of Cre with green fluorescent protein (GFP) identified two regions that are necessary for nuclear localization. Region I contains a cluster of basic amino acids that is essential for nuclear localization and which resembles a bipartite-like nuclear localization signal. Region II exhibits a beta-sheet structure with which the bipartite motif may interact. However, neither region is by itself sufficient for nuclear localization. Nuclear transport in vitro with a 98 kDa GFP-Cre fusion protein shows that Cre does not gain access to the nucleus by passive diffusion, but instead enters the nucleus by means of an energy-dependent process. Thus, Cre is one of the few prokaryotic proteins that have been shown to carry determinants that allow it to target the eukaryotic nucleus.
Multiple small RNAs identified in Mycobacterium bovis BCG are also expressed in Mycobacterium tuberculosis and Mycobacterium smegmatis

Tuberculosis (TB) is a major global health problem, infecting millions of people each year. The causative agent of TB, Mycobacterium tuberculosis, is one of the world’s most ancient and successful pathogens. However, until recently, no work on small regulatory RNAs had been performed in this organism. Regulatory RNAs are found in all three domains of life, and have already been shown to regulate virulence in well-known pathogens, such as Staphylococcus aureus and Vibrio cholera. Here we report the discovery of 34 novel small RNAs (sRNAs) in the TB-complex M. bovis BCG, using a combination of experimental and computational approaches. Putative homologues of many of these sRNAs were also identified in M. tuberculosis and/or M. smegmatis. Those sRNAs that are also expressed in the non-pathogenic M. smegmatis could be functioning to regulate conserved cellular functions. In contrast, those sRNAs identified specifically in M. tuberculosis could be functioning in mediation of virulence, thus rendering them potential targets for novel antimycobacterials. Various features and regulatory aspects of some of these sRNAs are discussed.
Model-based generation of low distortion currents in grid-coupled PWM-inverters using an LCL output filter

In this work, a single phase LCL output stage for grid coupled applications is built and evaluated. An accurate model and observer of the output filter and the distorted grid voltage is implemented. This paper deals with the construction of a 14-state model, and the feedback control loop to obtain good closed loop response. Simulations indicate a good performance of the controller, with a total harmonic current distortion (THD) below 1%. Experimental results confirm the simulations, and illustrate the good operation of the Kalman observer to estimate the distorted grid voltage (THD 3%). The output filter effectively reduces the PWM harmonics in the grid current.
Reevaluating Musculoskeletal Linkages in Suction-Feeding Fishes with X-Ray Reconstruction of Moving Morphology (XROMM)

Synopsis Suction-feeding fishes encompass a vast diversity of morphologies and ecologies, but during feeding they all rely on musculoskeletal linkages and levers to transform the shortening of muscle into 3D expansion of the mouth cavity. To relate the shape of these skeletal elements to their function in expansion of the mouth, four-bar linkage models have been developed and widely used in studies of ecology, evolution, and development. However, we have lacked the ability to test the predictions of these 2D linkage models against the actual 3D motions of fishes’ skulls. A new imaging method, X-ray Reconstruction of Moving Morphology (XROMM), now makes it possible to measure 3D skeletal motions relative to other bones within the head and relative to the fish’s body, and thereby to examine directly the proposed linkages. We used XROMM to examine the opercular linkage, in which shortening of the levator operculi muscle is hypothesized to retract the operculum, and thereby the interoperculum and interoperculomandibular ligament to generate depression of the lower jaw about the quadratomandibular joint. XROMM animations of suction strikes in largemouth bass revealed that the operculum is indeed retracted relative to the suspensorium as the levator operculi muscle shortens and the jaw depresses. However, the four-bar model of this linkage overestimates the depression of the jaw by nearly a factor of two. Therefore, caution should be used in interpreting and applying the predictions of this linkage model. When we measured kinematics relative to the fish’s body, we found that the operculum was relatively stable, whereas the suspensorium was elevated along with the neurocranium, pushing the quadratomandibular joint forward to produce depression of the jaw. Thus, it is the epaxial muscles elevating the neurocranium that powers depression of the jaw through the opercular linkage. However, the levator operculi muscle plays a crucial role in stabilizing the operculum to allow elevation of the head to produce depression of the lower jaw. These results support the role of cranial muscles in controlling and transmitting power from the axial muscles, rather than generating substantial power themselves. We also demonstrate the utility of XROMM for assessing the function of this, and other, cranial linkages in suction-feeding fishes.
State Abortion Policy and Unintended Birth Rates in the United States

Restrictive state abortion laws make it more difficult and costly for women to obtain an abortion. The fundamental law of demand posits that an increase in the cost of an abortion should cause the number of abortions to decrease. This suggests that restrictive state abortion laws should cause women with unintended pregnancies to have fewer abortions and concomitantly more unintended births. This paper investigates the impact four restrictive state abortion laws—No Medicaid Funding, Parental Involvement, Mandatory Counseling and Waiting Periods—have on the unintended birth rates of the 50 US states for the year 2006. Using a variety of methodologies, the empirical results show that, contrary to the theoretical prediction, these four antiabortion laws do not have a significant positive effect on unintended birth rates.
Implementing Modified Achievement Tests: Questions, Challenges, Pretending, and Potential Negative Consequences

This chapter discusses findings from the General Supervision Enhancement Grant awarded to the state of Pennsylvania by the US Department of Education’s Office of Special Education Programs for which the authors provide research support and consultation. The views and commentary expressed therein are solely those of the authors. No official support or endorsement by the US Department of Education or the Pennsylvania Department of Education is intended or to be inferred. We thank the editors, Deborah Fulmer, and Jane Partanen for comments on earlier drafts.
Plenary talk: Optimization in industry: From statistics to evolutionary methods in design and management applications

This talk will use the example of a real design task to illustrate the interplay between evolutionary methods, systems management and statistical techniques in the solution of complex technical issues. Systems management, notably requirements determination techniques, encompass the planning of optimization activities and proper allocation of resources to accomplish them. Evolutionary algorithms and statistical methods based on classification are then used to solve the optimization procedures necessary to fulfill the requirements previously developed. A conclusion is presented emphasizing the role of optimization in industry from a consumer/market viewpoint.
Modification of viral synthesis in tissue culture by substituting pyruvate for glucose in the medium.

SummaryChorioallantoic membrane tissue cultures (CamTC) in balanced salt solution (BSS) with pyruvate as the sole carbon source supported synthesis of influenza virus (strain WS) but not its neurotropic variant (strain NWS). Various other substrates were studied alone and together with pyruvate for their effect on synthesis of strain NWS in chorioallantoic membrane. Cells maintained in BSS containing glucose, xylose, or glycerol as the sole carbon source supported viral synthesis, while cells maintained in ribose, dihydroxyacetone, glycerophosphate, adenosine-5 phosphate, adenosine diphosphate, adenosine triphosphate, or diphosphopyridine nucleotide supported viral synthesis only in combination with pyruvate. It is suggested that synthesis of strain NWS in CamTC requires nutritional factors which are not supplied by cells maintained in a medium with pyruvate as the sole carbon source.
CD4+ T-Lymphocytes prevent reactivation of toxoplasmic encephalitis (TE) in the SCID mouse

TE is common life-threatening opportunistic infection in patients with AIDS. We have recently developed a model of TE reactivation using the SCID mouse (Clin Res 1992:40;I75A). The objective of the current study was to use this model to determine the mechanisms of resistance to reactivation of TE. Immune Balb/c spleen cells were treated with monoclonal antibodies (MAb) and complement in vitro to deplete specific lymphocyte subsets prior to transfer lo SCID mice chronically infected with T.gondii. Mice then received MAb in vivo to maintain lymphocyte subset depletion. Cells depleted of both CD4+ and CD8+ cells resulted in a significant increase in mortality over controls (p = 001). Severe necrotising encephalitis associated with many T.gondii organisms were seen in CD4+/CD8+ depleted mice whereas control animals only had mild meningeal and perivascular inflammation. CD4+ or CD8+ depleted animals did not die, however whereas CD4+ depleted animals developed necrotic brain lesions associated with T.gondii., CD8+ depleted micc only developed mild meningeal and perivascular inflammation which were similar to lesions seen in controls. Depletion of CD4+ cells resulted in markedly reduced serum levels of interferon-γ (IFN-γ) and interleukin-6 (IL-6) as well as markedly impaired production of IFN-γ, IL-6, IL-4 and IL-10 (by ELISA) in splenic cultures stimulated with concanavalin A or toxoplasma lysale antigen. We conclude that in this model of TE: (I) Resistance from reactivation of TE is mediated by lymphocytes. (2) CD4+ cells appear to be more important than CD8+ cells in mediating such resistance. (3) Impairment of cytokine production due to CD4 depletion appears to play a role in reactivation of TE. (4) These results should assist in our understanding the Immunopathogenesis of TE in AIDS patients.
Serological survey on viral hepatitis B in the population of Shanxi province

为了解我国不同地区、不同年龄人群乙型病毒性肝炎(乙肝)的流行现状,于2006年9月在山西省开展了人群乙肝血清流行病学调查,现将调查结果报道如下. 1.对象与方法:在山西省6个国家疾病监测点(县)和1个矿区,采用多阶段随机抽样法,随机抽取1～59岁常住人口3083人作为调查对象.用统一调查表,对每个调查对象进行个案调查.调查内容包括一般情况、肝炎患病史、乙肝病毒暴露史、疫苗免疫史等.对所有调查对象采静脉血标本2 ml,由中国CDC病毒病预防控制所采用ELISA进行检测.检测项目有HBsAg、抗-HBs、抗-HBc.采用EpiData 3.1软件建立数据库.用SPSS软件进行统计分析。
Television News and the Supreme Court: A Tale of Two Cases: Bakke and Webster

“One of the more unfortunate things about the Bakke case is that it became the vehicle for educating, or should I say miseducating, the public about affirmative action. The public learned about affirmative action almost, literally, for the first time through … ten-second sound bites on television, with people polarized against one another.” Eleanor Holmes Norton, while a member of the Equal Employment Opportunity Commission (in Blackside, 1989) “[F]ollowing Webster , some network reporters suggested a lockup, giving each reporter five minutes … to study the decision … so they could all report the decision more responsibly.” Tim O'Brien, ABC News On June 28, 1978, the Supreme Court issued its much anticipated ruling in the case of Regents of the University of California v. Bakke . Allan Bakke, a white male, claimed that he was discriminated against by the medical school at the University of California at Davis (UC-Davis) because of his race. The celebrated case marked the Court's first full-scale effort to address the legality of publicly promulgated affirmative action programs, in this instance in the context of admissions processes at a professional school. More than a decade later, on July 3, 1989, the Court issued its decision in the similarly anticipated case of Webster v. Reproductive Health Services , dealing with the constitutionality of several provisions of a Missouri law that regulated and restricted a woman's right to obtain an abortion. This time the Court was not working on a clean slate, however, since it had revisited the issue of abortion rights many times in the wake of the landmark Roe v. Wade ruling in 1973 overturning a Texas antiabortion statute.
Lifeways in Andahuaylas Under the Aegis of the Wari Empire and After Its Collapse

Andahuaylas, in the south central Andean mountains of Peru, was an important near-hinterland province during the Wari imperial era, a period scholars called the Middle Horizon. Archaeological and bioarchaeological data are employed to elucidate the socioeconomic role that Wari played in this region that, crucially, served as an obligatory byway within a vast road network. The archaic empire’s enigmatic fragmentation launches a discussion of the ensuing period, often termed the early Late Intermediate. During this transitional era, paleoclimatic evidence, ethnohistoric documents, and settlement, architectural, and artifactual data provide a context for understanding the coalescence of two of Andahuaylas’ most notable polities. A majority group, called the Chanka, formed defensive communities that dotted much of Andahuaylas, while a minority group, known as the Quichua, maintained resistant enclaves in the province.