cssi/SciSciGPT-SciSciNet huggingface dataset:
Business groups and social welfare in emerging markets: Existing evidence and unanswered questions

Abstract This paper reviews existing studies of the role of emerging market business groups, a ubiquitous but poorly understood organizational form. I first suggest that understanding the definition of business groups is itself an interesting, albeit under-studied, research issue. I then argue that the existing evidence suggests that the performance effects of group affiliation are large and generally positive. There is substantial evidence that part of this is due to welfare-enhancing functions originating in the idea that groups substitute for missing outside institutions, but that part is also due to welfare-reducing minority shareholder exploitation. Evidence is lacking on the extent to which groups facilitate rent-seeking or the exercise of market power. Evidence is also lacking on the extent to which groups hamper the future development of markets. The paper identifies areas where research is needed before current competition policy experiments in countries like China, India and Korea can be evaluated.
Structure-activity relationships in aquatic toxicology

Relationships among chemical structure, aquatic toxicity, and bioconcentration potential were examined for several classes of organic compounds. Structure-toxicity correlations were based largely on median lethal concentrations (LC50) and toxicant threshold concentrations (LC1) determined in mini-chronic tests with early life stages of fish and amphibians. Exposure was initiated at fertilization and maintained through 4 days posthatching. Bioconcentration potential was assessed using n-octanol/water partition coefficients (log P). In tests with polychlorinated biphenyls (PCB), acute and chronic toxicity generally increased with percent chlorination. In addition, toxicity of specific PCB's appeared to be affected by the ratio of less chlorinated to more highly chlorinated isomers. The toxicity of chlorinated methanes (i.e., methylene chloride, chloroform, carbon tetrachloride) also increased with chlorination. Concerning single ring aromatic compounds, pyridine was much less toxic than benzene and benzene was less toxic than its mono-substituted derivatives, including chlorobenzene, nitrobenzene, toluene, and phenol. However, no consistent order of toxicity was observed for the substituted compounds. Acute toxicity also increased with the number of aromatic rings in a series of nitrogen heterocyclic compounds, and the latter were less toxic than corresponding alicyclic compounds. Within most classes of compounds, a direct correlation was observed between acute toxicity and bioconcentration potential. As observed with PCB compounds, the mini-chronic test described in this study permitted evaluations of structure-activity relationships using both LC50 and LC1 values determined with early life stages. The LC1's compared well with results obtained in life-cycle studies, thus providing an economical and reliable means of estimating chronic values for reproductive impairment.
Identification of a viral gene encoding a ubiquitin-like protein.

Abstract The baculovirus Autographa californica nuclear polyhedrosis virus (AcMNPV, which is representative of the MNPV subtype in which the virions may contain many nucleocapsids within a single viral envelope) encodes a protein, v-ubi, that has 76% identity with the eukaryotic protein ubiquitin. Transcriptional mapping indicated that the gene for v-ubi was transcribed during the late phase of viral infection. Two transcriptional start sites potentially encoding v-ubi were identified. Both sites were contained within a sequence motif common to baculovirus late genes. A recombinant virus, AcUbi-beta Gal, encoding a ubiquitin-beta-galactosidase fusion protein was constructed to monitor the temporal regulation of v-ubi gene during viral infection. The fusion protein was expressed maximally at 14-18 hr postinfection, consistent with its classification as a late protein. The amount of ubiquitin-beta-galactosidase fusion protein that accumulated in AcUbi-beta Gal-infected cells by 48 hr postinfection was approximately 14% of the level of beta-galactosidase that was synthesized under control of the polyhedrin promoter. Transcriptional analysis confirmed that synthesis of the fusion protein was directed by the v-ubi gene promoter. AcUbi-beta Gal also produced normal levels of authentic viral ubiquitin message. Southern blot analysis of AcUbi-beta Gal and 15 additional isolates revealed that the fusion sequences had not recombined at the ubiquitin locus. A polyubiquitin gene was isolated and sequenced from Spodoptera frugiperda, a lepidopteran host cell line for AcMNPV. The predicted amino acid sequence of the product of the host gene is identical to animal ubiquitin.
What You Don't Know May Kill You: The Importance of Including Sexual Health in Premarital Counseling

Sexual health is a widespread concern for intimate partners. As couples transition to marriage, it is vitally important to explore issues related to sexual health. Moreover, premarital counselors a...
An Instructional Exercise in Price Controls: Product Quality, Misallocation, and Public Policy

Price controls are a contentious topic in society and hence a good source for economics classroom engagement. The standard textbook analysis of price controls is lacking, however. This paper presents real-world examples and classroom exercises on the topic of price controls. The exercises complement the standard textbook analysis of price controls by including costs related to misallocation and quality degradation. The discussion questions and analytical exercises provide students with a broad view of price controls and their policy implications.
Probing Cytoskeletal Mechanics Using Biochemical Inhibitors

Quantifying the mechanics of the cytoskeletons of living cells is important for understanding several physiologic and pathologic cellular functions, such as wound healing and cellular migration in cancer. Our laboratory develops three-dimensional tissue constructs for assaying cytoskeletal mechanics in controlled conditions. These tissue constructs consist of defined components such as chick embryo fibroblasts and reconstituted rat tail collagen; fibroblasts remodel the collagen extracellular matrix (ECM) and develop a structural environment representative of that which would exist in a natural tissue.Our protocol for quantifying the microscale mechanics of the proteins that comprise the cytoskeleton involves mechanical testing of a tissue construct first in a bath that contains nutrition medium to support the active physiologic functioning of the cells, and next in the presence of inhibitors that selectively eliminate specific cytoskeletal structures. By solving an inverse homogenization problem, the mechanical functioning of these proteins at the cellular level can be estimated. Here, we present a combination of mechanical testing and imaging results to quantify the effects of specific inhibitors on cytoskeletal and extracellular matrix form and function.Copyright © 2010 by ASME
Higher bone matrix density exists in only a subset of patients with bisphosphonate-related osteonecrosis of the jaw.

Purpose Because few treatment options exist for bisphosphonate-related osteonecrosis of the jaw (BRONJ), developing methods of early detection and prevention is vital. Computed tomography could represent a useful tool for early detection of BRONJ, yet its effectiveness would necessitate changes in tissue density. The aim of this study was to quantify bone matrix density of tissue from patients with BRONJ. Patients and Methods Bone samples from 13 patients with confirmed BRONJ were scanned by use of high-resolution micro-computed tomography. Mean density and density distribution were assessed and compared with mandible samples from cadaveric controls (n = 8; age range, 43-94 years). Results The bone matrix in BRONJ samples had a significantly higher mean density (+8.5%, P = .01) compared with cadaveric samples. The higher density in BRONJ tissue was evident in a clear shift in the tissue density profile. In controls, less than 5% of the tissue had a density above the median gray-scale value, whereas on average, BRONJ tissue had approximately 15% of the tissue density in this range. By use of z score analyses of mean density values, a large degree of heterogeneity is evident among BRONJ specimens, with some samples having z scores of 0 and others having z scores well above 6 compared with controls. Conclusions On the basis of these findings, higher tissue density appears to manifest in only a subset of BRONJ patients, suggesting that density may have limitations as a biomarker for early detection of this condition.
The neurosteroids pregnenolone and pregnenolone-sulfate but not progesterone, block Ca2+ currents in acutely isolated hippocampal CA1 neurons

The neurosteroids pregnenolone (PE) and pregnenolone-sulfate (PS) have been shown to interact with the GABAA receptor in the central nervous system. In contrast, nothing is known of any possible modulation of voltage-gated calcium channels (VGCC). We have examined the interaction of PE, PS and progesterone on VGCC in acutely isolated adult guinea-pig hippocampal CA1 neurons using the whole-cell patch clamp technique. PE and PS depressed the calcium current at low micromolar concentrations (0.001 – 100 μM). The time to peak of the calcium current was slowed by PE and PS. The blocking action of PE and PS occurs in the presence of 10 μM picrotoxin. In contrast, progesterone had no effect on the Ca2+ current, indicating specificity for PE and PS. These results demonstrate a direct and novel membrane site of action for PE and PS, suggesting a possible role influencing brain excitability.
Design and analysis of the tracker bridge for the Hobby-Eberly Telescope wide-field upgrade

A large structural weldment has been designed to serve as the new star tracker bridge for the Wide Field Upgrade to the Hobby-Eberly Telescope at McDonald Observatory in support of the Hobby-Eberly Telescope Dark Energy Experiment  . The modeling approach, analysis techniques and design details will be of interest to designers of large structures where stiffness is the primary design driver. The design includes detailed structural analysis using finite element models to maximize natural frequency response and limit deflections and light obscuration. Considerable fabrication challenges are overcome to allow integration of precision hardware required for positioning the corrector optics to a precision of less than 5 microns along the 4-meter travel range. Detailed descriptions of the bridge geometry, analysis results and challenging fabrication issues are discussed.
A eukaryotic vector for the expression of genes or gene fragments

Abstract The eukaryotic vector described is useful for the expression of foreign genes or gene fragments. In the case of gene fragments that lack their own initiation codon, this vector provides an initiation condon (ATG), and the product is made as a fusion protein of T-antigen (10–11 amino acids from the amino terminal region of T-antigen). Some useful features of this vector are: 1) it replicates in bacterial and mammalian cells; 2) it provides splice and polyadenylation signals; 3) it provides initiation codon (ATG) for gene fragments that lack them.
Quantitation and prevalence of tympanosclerosis in a pediatric otolaryngology clinic

Abstract Objective: To determine the incidence and prevalence of tympanosclerosis (TS) in patients seen in a pediatric otolaryngology clinic. Design: Prospective observational study. Setting: Tertiary care, ambulatory care clinic. Patients and other participants: We conducted a prospective observational study to determine the incidence of TS in 218 patients seen consecutively in a pediatric otolaryngology clinic for otologic and nonotologic reasons. The patient age range was 3 weeks to 30 years; 63% were male and 37% female. Of the 218 patients, 37% (81) had undergone bilateral myringotomy and tube placement (BMT 63% (137) of the 218 patients had no history of otologic surgery, but 12% (15) of the 137 showed signs of TS. Method: The area of the tympanic membrane affected by TS was determined by otoscopy performed by one viewer, who drew the otoscopic findings on a standardized tympanic membrane template. The area of TS was quantified in terms of percentages by digital image analysis of the scaled drawings. Results: There was a range of 0.5–59.9% involvement of the tympanic membrane with TS, with the median percentage of involvement being 4.95%. There was an increased percentage of TS with repeat BM&T. Conclusion: This observational study shows that patients who have had BM&T have a higher incidence of TS than those who have not had the surgery. However our findings also show that 38% of the patients in this study who had TS had never undergone BM&T.
Transforming the fight against tuberculosis: Targeting catalysts of transmission

The global tuberculosis control community has committed itself to ambitious 10-year targets. To meet these targets, biomedical advances alone will be insufficient; a more targeted public health tuberculosis strategy is also needed. We highlight the role of “tuberculosis transmission catalysts,” defined as variabilities in human behavior, bacillary properties, and host physiology that fuel the propagation of active tuberculosis at the local level. These catalysts can be categorized as factors that increase contact rates, infectiousness, or host susceptibility. Different catalysts predominate in different epidemiological and sociopolitical settings, and public health approaches are likely to succeed only if they are tailored to target the major catalysts driving transmission in the corresponding community. We argue that global tuberculosis policy should move from a country-level focus to a strategy that prioritizes collection of data on key transmission catalysts at the local level followed by deployment of “catalyst-targeted” interventions, supported by strengthened health systems.
View Propagation and Inconsistency Detection for Cooperative Mobile Agents

Mobile agents are autonomous programs that migrate from one machine to another within a network on behalf of a client, thus, they are ideal for mobile computing environments since tasks can be delegated to mobile agents when a mobile client is disconnected. This paper extends the traditional functionality of a mobile service agent with capabilities that facilitate asynchronous cooperation among mobile database clients. In the context of mobile client-server database applications, data cached to support disconnected operations can take the form of a materialized view. We design mobile agents to reduce computation and wireless communication costs, and use view versioning to cope with disconnected operations by allowing application sessions to access current data without invalidating work previously done. A data validation or results propagation process detects inconsistencies with newer versions of data upon reconnection. Essentially, these mobile agents will compute the period of time or consistency window, measured in versions, for which the results of a mobile client's application are consistent. We supply rules that govern the creation and sharing of results and show how inconsistencies can be detected to offer a higher availability of data while organizing and gracefully degrading the amount of consistency achieved between the mobile clients and the data sources.
Diverticulitis in the younger patient

Abstract Background The purpose of this study was to examine the presentation of diverticulitis at an urban county hospital serving predominantly indigent patients and to analyze the differences, if any, in presentation and treatment in younger patients. Methods A retrospective review of medical records from 1995 to 2001 was performed at a single institution to identify patients admitted to the surgical service with the diagnosis of diverticular disease. Inclusion criteria were either diverticulitis confirmed at operation or radiographic findings consistent with the disease. Patient demographics, history, pertinent physical findings, and treatment were recorded. The data were analyzed after dividing the patients into two populations: a younger population 50 years of age or less, and a second population of patients older than 50. Results During the interval, a total of 64 patients were admitted to the surgical service with the diagnosis of diverticulitis. The mean age of this population was 45.5 years (range 21 to 86). Forty-six patients were under 50 years of age (72%). Analysis of sex differences, type and timing of surgical procedure, and complication rate with respect to age showed no significant difference between the two age groups. Conclusions We are clearly treating a younger patient population than previous reports on patients with diverticulitis. Although there was a trend toward increased surgical intervention in the younger population, this number did not reach statistical significance. Diverticulitis in young patients at our institution does not appear to take a more aggressive course than the same disease in older patients.
Gastrointestinal microbial ecology and the safety of our food supply as related to Salmonella.

Salmonella causes an estimated 1.3 million human foodborne illnesses and more than 500 deaths each year in the United States, representing an annual estimated cost to the economy of approximately $2.4 billion. Salmonella enterica comprises more than 2,500 serotypes. With this genetic and environmental diversity, serotypes are adapted to live in a variety of hosts, which may or may not manifest with clinical illness. Thus, Salmonella presents a multifaceted threat to food production and safety. Salmonella have been isolated from all food animals and can cause mor- bidityandmortalityinswine,cattle,sheep,andpoultry. The link between human salmonellosis and host ani- mals is most clear in poultry. During the early part of the 20th century, a successful campaign was waged to eliminate fowl typhoid caused by Salmonella Galli- narum/Pullorum. Microbial ecology is much like ma- croecology; environmental niches are filled by adapted and specialized species. Elimination of S. Gallinarum cleared a niche in the on-farm and intestinal microbial ecologythatwasquicklyexploitedbySalmonellaEnter-
4:47 Percutaneous vertebroplasty and kyphoplasty for painful vertebral body fractures in cancer patients

Object. The current North American experience with minimally invasive vertebro- and kyphoplasty is largely limited to the treatment of benign osteoporotic compression fractures. The objective of this study was to assess the safety and efficacy of these procedures for painful vertebral body (VB) fractures in cancer patients. Methods. The authors reviewed a consecutive group of cancer patients (21 with myeloma and 35 with other primary malignancies) undergoing vertebro- and kyphoplasty at their institution. Ninety-seven (65 vertebro- and 32 kyphoplasty) procedures were performed in 56 patients during 58 treatment sessions. The mean patient age was 62 years (± 13 years [standard deviation]) and the median duration of symptoms was 3.2 months. All patients suffered intractable spinal pain secondary to VB fractures. Patients noted marked or complete pain relief after 49 procedures (84%), and no change after five procedures (9%); early postoperative Visual Analog Scale (VAS) pain scores were unavailable in four ...
Effect of sea-level rise on piping plover (Charadrius melodus) breeding habitat

Abstract Climate change is raising sea levels, threatening many low-lying coastal areas and associated wildlife. We assessed the threat of sea-level rise (SLR) to the breeding habitat of the federally threatened piping plover on the barrier islands of Suffolk County, New York. We determined the extent of habitat change over the next 100 years under several SLR estimates, as well as the interactive effects of coastal development and storm surge. We found that if plover habitat cannot migrate, SLR is likely to reduce breeding areas. However, if habitat is able to migrate upslope and inland, breeding areas could actually increase with SLR. Unfortunately, this potential habitat gain is stymied by human development, which we found to reduce migrating habitat by 5–12%, depending on SLR estimates. We also found that the spatial configuration of developed areas mattered more than intensity of development in blocking the migration of potential habitat area. Our results raise concern over the likelihood of increased conflict between plover habitat protection and human recreation as habitat is likely to become a larger proportion of the barrier islands in the future. Finally, our results highlight risk from the synergism between SLR and coastal storms, as we estimate that a large hurricane could flood up to 95% of plover habitat. To assure the future of plover habitat on these barrier islands, management needs to promote natural overwash and habitat migration, while minimizing development adjacent to future breeding habitat.
Effective Antenna Pattern of Scanning Radars

It is shown that weather radar signal averaging causes a broadened apparent pattern of the scanning radar antenna. The apparent pattern is obtained by convolving the original pattern with the averaging circuit impulse response. Echo displacement and pattern broadness are examined for square law, linear, and logarithmic detectors having exponential and finite time integrators.
Lung Cancer Detection and Prevention: Evidence for an Interaction between Smoking and Genetic Predisposition

The initiation and promotion of cancer is thought to result from a series of genetic mutations, some of which may be inherited. Our analysis of 337 lung cancer families suggested that, after allowing for an individual's pack-years of tobacco use, the pattern of disease was best explained by Mendelian codominant inheritance of an allele that produced earlier age of onset. Since lung cancer rarely occurs in the absence of exposure to tobacco, differences in the prevalence of smoking across generations could have a profound influence on the fit of genetic models. In the present study, families were partitioned into two groups, based on the birth cohort of the proband, i.e. , born before World War I (age at death, ≥60 years) or born after World War I (age at death, <60 years). This partition was chosen because the year 1915 signaled the start of the dramatic rise in tobacco use in the United States. In younger proband families, in which parents were more likely to smoke, Mendelian codominant inheritance provided the best fit to the data. In older proband families, for whom smoking among parents was less prevalent, the “no major gene” and “environmental” hypotheses were rejected; however, no Mendelian models could be distinguished. If the results on the families with the most homogeneous exposure to tobacco across generations (born after World War I) reflect the true underlying biology, then the influence of genetic factors in the pathogenesis of lung has been underestimated; the cumulative probability of lung cancer at age 80 for a noncarrier of the gene, at the average level of tobacco consumption, is close to zero, implying that virtually all lung cancer occurs among gene carriers. Identification of this putative genetic factor has profound implications for the detection and prevention of lung cancer.
Agent-based modeling of malware dynamics in heterogeneous environments

The increasing convergence of power-law networks such as social networking and peer-to-peer applications, web-delivered applications, and mobile platforms makes today’s users highly vulnerable to entirely new generations of malware that exploit vulnerabilities in web applications and mobile platforms for new infections, while using the power-law connectivity for finding new victims. The traditional epidemic models based on assumptions of homogeneity, average-degree distributions, and perfect-mixing are inadequate to model this type of malware propagation. In this paper, we study four aspects crucial to modeling malware propagation: application-level interactions among users of such networks, local network structure, user mobility, and network coordination of malware such as botnets. Since closed-form solutions of malware propagation considering these aspects are difficult to obtain, we describe an open-source, flexible agent-based emulation framework that can be used by malware researchers for studying today’s complex malware. The framework, called Agent-Based Malware Modeling (AMM), allows different applications, network structure, network coordination, and user mobility in either a geographic or a logical domain to study various infection and propagation scenarios. In addition to traditional worms and viruses, the framework also allows modeling network coordination of malware such as botnets. The majority of the parameters used in the framework can be derived from real-life network traces collected from a network, and therefore, represent realistic malware propagation and infection scenarios. As representative examples, we examine two well-known malware spreading mechanisms: (i) a malicious virus such as Cabir spreading among the subscribers of a cellular network using Bluetooth and (ii) a hybrid worm that exploit email and file-sharing to infect users of a social network. In both cases, we identify the parameters most important to the spread of the epidemic based upon our extensive simulation results. Copyright © 2011 John Wiley & Sons, Ltd.
Modeling and investigation of a geometrically complex UWB GPR antenna using FDTD

A detailed analysis of ultrawide-band (UWB), dual-polarized, dielectric-loaded horn-fed bow-tie (HFB) antennas is carried out using the finite-difference time-domain (FDTD) method. The FDTD model includes realistic features of the antenna structure such as the feeding cables, wave launchers, dielectric loading, and resistive-film loading. Important antenna characteristics that are usually difficult to obtain via measurements can be obtained more directly from this FDTD model. Since the HFB antennas under consideration are intended for ground penetrating radar (GPR) applications, the effects of the half-space medium are also investigated. The simulated results serve to verify the performance of the HFB antenna design, and to optimize various antenna parameters.
Purposeful mobility for relaying and surveillance in mobile ad hoc sensor networks

We consider a mobile ad hoc sensor network. The mobility of the sensor nodes is designed with the cost of communication and mobility in mind along with consideration of the possible scanning tasks of the nodes. Our mobility algorithm is developed in the context of a distributed system where, for any single mobile node, only local information about associated energy costs is known. We use a distributed simulated annealing framework to govern the motion of the nodes and prove that, in a limiting sense, a global objective function comprising mobility and communication energy costs are minimized. This paper concludes with a simulation study focusing on mobile sensors with dual roles of scanning and relaying higher priority tracking traffic from tracking nodes.
Superconducting Magnets and Cryogenics

Several significant superconducting beam line magnet systems are being constructed in the U.S. These will demonstrate the practicability of superconductors in beam lines. It is now time to consider some of the more subtle engineering problems associated with these magnets in order to assure a "next generation" of highly usable magnets. This paper presents some engineering approachs to better magnets for the future.
Graphics Processing Unit Accelerated $O(N)$ Micromagnetic Solver

An efficient micromagnetic solver running on graphics processing units (GPU) is demonstrated. The solver implements a nonuniform grid interpolation method (NGIM) to compute the superposition integral for the magnetostatic field with operations and memory requirements. The NGIM divides the computational domain into a hierarchy of boxes containing sources and observers, and it uses spatial interpolation from sparse nonuniform grids to achieve computational savings. Efficiency of the GPU solver is achieved by using coalesced memory accessing requiring arranging data in contiguous addresses, one-block-per-box computations with a block of threads handling an observation box to achieve the best utilization of the GPU threads, and on-fly computation of all grids and interpolation coefficients leading to reduced memory and increased speed. The GPU-CPU speed-ups are shown to be in the range 40-100 depending on the problem size and accuracy. A simple and inexpensive GPU is shown to handle efficiently problems comprising discretizations of more than 16 million of spins.
Round Spermatid-Specific Transcription of the Mouse SP-10 Gene Is Mediated by a 294-Base Pair Proximal Promoter

Spermiogenesis is the terminal phase of male germ cell differentiation during which haploid spermatids engage in coordinate expression of a number of testis-specific genes, including those specifying acrosomal proteins. To begin to understand the transcriptional regulation during acrosomal biogenesis, we initiated promoter analysis of the gene encoding the acrosomal protein SP-10. SP-10 was previously shown to be transcribed within Golgi-phase round spermatids in the human. The present study characterizes SP-10 gene expression during spermiogenesis in the mouse and identifies regions of the mouse SP-10 (mSP-10) promoter that are capable of driving round spermatid-specific transcription in vivo. Expression of mSP-10 mRNA was initiated in early round spermatids coincident with acrosomal biogenesis and was terminated prior to nuclear elongation. The core promoter of mSP-10 lacked a TATA box but contained a canonical initiator (Inr) element surrounding the transcription start site. Using transgenic mice, we showed that the -408 to +28-base pair (bp) or the -266 to +28-bp mSP-10 5' flanking region is sufficient to direct round spermatid-specific expression of a green fluorescent protein reporter gene. On the other hand, the -91 to +28-bp mSP-10 gene fragment lacked promoter activity in vivo. This is the first functional characterization of a testis-specific gene promoter active in early round spermatids.
Ultrastructure of proliferative ileitis in hamsters (Mesocricetus auratus)

Summary The ileum of affected hamsters bore microvilli which were much shorter, less regularly arranged and less densely packed than those from control animals. Organelle derangements such as atrophy of mitochondria, degranulation and dilated cisterna of endoplasmic reticulum, were observed. Some hyperplastic epithelial cells contained multiple intracytoplasmic inclusion bodies and amyloid deposits were present extracellularly. Proliferative ileitis (wet-tail syndrome) in hamsters is an important enteropathies characterized by dehydration, diarrhoea and emaciation (Booth & Cheville, 1967). It has been repeatedly found as a major obstacle by those making use of this species in prolonged medical research. Affected animals invariably display a marked thickening and enlargement of the terminal ileum. Jonas, Tomita & Wyand (1965) described this condition as enzootic intestinal adenocarcinoma, but Booth & Cheville (1967), who studied similar con· ditions in 92 hamsters, ruled against the neoplastic theory. They suggested that epithelial hyperplasia of the ileal mucosae followed by severe inflammatory cell response was responsible for the thickening of the ileum and adjacent structures. The cause of intestinal epithelial hyperplasia remains controversial, although a number of bacterial and viral agents have been recovered. Ultrastructural studies of proliferative ileitis in hamsters have revealed intracellular bacterial organisms resembling Escherichia coli (Wagner, Owens & Troutt, 1973). However, the observed bacterial organisms could not fulfill Koch's postulates (Booth & Cheville, 1967; Jonas el aI., 1965). In hopes of elucidating the aetiology and accompanying ultrastructural changes, we have examined 3 typical cases of proliferative ileitis by electron microscopy.
An Integrative Review Of 2/4 Transfer Programs

This integrative review paper examines the most recent research data as it pertains to transfer programs between two-year and four-year colleges in the United States. This examination is guided by the research question: What are the suggested components of a quality transfer program? Suggested components of transfer programs are Transfer Centers which provide one location for transfer student services. These services should include: (a) advising services; (b) pre-transfer orientation programs; (c) access to four-year academic clubs, student organizations, peer mentoring programs and special networking sessions; (d) a method of tracking the transfer student’s performance; and (e) internet access. Transfer student transition is a collaborative service process among transfer students, community colleges, and 4-year universities, working together to assist with the transition.
A large-scale on-chip droplet incubation chamber enables equal microbial culture time

In many droplet-based screening applications, applying an equal incubation or reaction time to a large number of droplets is critical since differences in incubation time can lead to false positive or false negative hits during the selection process. Even though many droplet incubation platforms have been successfully utilized, having all droplets incubated for equal duration remains a formidable challenge. Here, we present an on-chip droplet incubation chamber that is capable of providing a constant droplet incubation time for a large number of droplets. This first-in first-out droplet incubation chamber essentially functions as a delay compartment to ensure that all droplets have equal incubation time inside the chamber before moving on to the post-incubation assay steps. The functionality of the developed chamber was tested by tracking color dye droplets flowing through the on-chip incubation chamber as well as comparing the growth of droplet-encapsulated cells of a filamentous fungus Fusarium verticillioides. The incubation time can be easily adjusted by changing the volume of the chamber or droplet collection speed. The chamber can also be easily integrated on-chip with other droplet microfluidics functional modules such as droplet generators, detectors, and sorters without any valve and tubing connection.
X-ray Crystallographic Structure of Oligomers Formed by a Toxic β-Hairpin Derived from α-Synuclein: Trimers and Higher-Order Oligomers.

Oligomeric assemblies of the protein α-synuclein are thought to cause neurodegeneration in Parkinson’s disease and related synucleinopathies. Characterization of α-synuclein oligomers at high resolution is an outstanding challenge in the field of structural biology. The absence of high-resolution structures of oligomers formed by α-synuclein impedes understanding the synucleinopathies at the molecular level. This paper reports the X-ray crystallographic structure of oligomers formed by a peptide derived from residues 36–55 of α-synuclein. The peptide 1a adopts a β-hairpin structure, which assembles in a hierarchical fashion. Three β-hairpins assemble to form a triangular trimer. Three copies of the triangular trimer assemble to form a basket-shaped nonamer. Two nonamers pack to form an octadecamer. Molecular modeling suggests that full-length α-synuclein may also be able to assemble in this fashion. Circular dichroism spectroscopy demonstrates that peptide 1a interacts with anionic lipid bilayer membranes...
Enzyme Micropump‐Based Inhibitor Assays

Rapid, easy-to-use, and portable devices that can provide a read-out without the need for expensive equipment represent the future of sensing technology, with applications in areas like environmental, food, chemical, and biological safety. Enzymes immobilized on a surface function as micropumps in the presence of species (e.g., substrate, cofactor, or biomarker) that trigger the enzymatic reaction. The flow speed in these devices increases with increasing reaction rate. This allows the detection of substances that inhibit the enzymatic reaction. Using this principle, sensors for toxic substances, like mercury, cadmium, cyanide, and azide, were designed using urease and catalase-powered pumps, respectively, with limits of detection well below the concentrations permitted by the Environmental Protection Agency. The study was also extended to other inhibitors for these enzymes. The sensing range of fluid flow-based inhibitor assays depends on the type of inhibition, the enzyme concentration on the sensing platform, and, for competitive inhibition, the concentration of substrate used.
Effects of AEDs on Serum Nitrite and Nitrate Levels

Serum nitrite and nitrate levels were determined in 34 epileptic children treated with valproic acid and 23 with carbamazepine and compared to 38 non-active epileptic children with no antiepileptic drug therapy, in a study at KSU Medical School, Turkey.
Neue Technik für Höhere Warmfestigkeit von Aluminiumkolben

Die Temperaturen und Drucke in modernen Dieselmotoren steigen stetig an. Als Folge davon mussen auch Aluminiumkolben eine erhohte Warmfestigkeit aufweisen, um ausreichende Festigkeitsreserven zu bieten. Federal-Mogul erhoht mit der DuraBowl-Technologie — einer lokalen Nachbehandlung hochbelasteter Kolbenzonen — die Lebensdauer der Kolben um den Faktor vier bis acht.
Antiepileptic Drug-Induced Fetal Malformations

Women with epilepsy attending a single maternity clinic, Helsinki University Central Hospital, Finland, were followed prospectively during 970 pregnancies in 1980 through 1998.
Testicular regression ("vanishing testis") syndrome - A pathological study of 77 cases

Testicular regression syndrome is a condition characterised by a rudimentary epididymis and spermatic cord with absence of testicular tissue. Although it has been well described in the surgical literature, few pathological studies have been performed. To characterise the condition more clearly, a retrospective review was made, covering a 25 year period from 1965 to June 1990 at the Adelaide Children's Hospital Department of Histopathology. A total of 77 cases of testicular regression syndrome were found. Typical gross descriptions described several centimetres of spermatic cord with a small mass of firm, fibrotic tissue at one end. Elements of the spermatic cord, i.e. vas deferens, spermatic artery and venous plexi, were usually present. Histologically the distal expansion of most of the specimens was composed of dense fibrovascular tissue with no evidence of seminiferous tubules or normal testicular elements. Instead, scattered foci of calcification and brown pigment were present. Von Kossa staining confirmed the presence of calcium while Perls' and Schmeltzer's staining demonstrated the presence of both ferric and ferrous ions. A few cases included atrophic seminiferous tubules. The finding of dystrophic calcification with evidence of remote haemorrhage with no evidence of viable testicular tissue in the presence of relatively normal spermatic cord elements supports the concept of secondary anorchia resulting from infarction. The young age of the patients, coupled with the history of an absent testis from birth, is also supportive of in ulero damage This histopathologic study provides morphological support for the concept of in ulero torsion of the testis as the basis for the testicular regression syndrome.
Purification of anthrax-toxin components by high-performance anion-exchange, gel-filtration and hydrophobic-interaction chromatography

A procedure has been developed for purification of the tripartite anthrax-toxin components. This involves sequential high-performance anion-exchange, gel-filtration and hydrophobic-interaction chromatography. From an initial culture volume of 15 litres, typical yields of 8 mg of protective antigen, 13 mg of lethal factor and 7 mg of oedema factor are produced to higher degrees of purity than have previously been achieved by conventional chromatographic techniques.
Juvenile rheumatoid arthritis. Old challenges, new insights.

Preview What are the three main types of disease presentation in juvenile rheumatoid arthritis, and how do they relate to prognosis? Does infection or heredity play a role in causing the illness? Should aggressive therapy with multiple drugs be instituted early? Which therapeutic agents have the best chance of inducing remission? Dr Tibbitts addresses these and other questions in this overview of a disease that is a significant cause of chronic illness and disability in children.
Contribution of Low-Affinity Sites to Strong Multivalent Protein-Membrane Binding: Detection using Single-Molecule TIRF Microscopy

Biomolecular interactions such as interfacial protein-membrane binding are often the cumulative effect of multivalent attractions. We have shown that the stoichiometry of peripheral protein-membrane interactions can be measured based on single-molecule diffusion using supported lipid bilayers. Here we apply this technique to granuphilin, a synaptotagmin-like protein containing tandem membrane-targeting C2 domains, C2A and C2B. Granuphilin C2A binds simple lipid membranes containing anionic lipids such as phosphatidylserine (PS), but C2B affinity for PS is undetectable using standard protein-membrane binding approaches. Here, we set out to determine the PS affinity of C2B based on a comparison of the diffusion rates of the C2A domain and the C2AB tandem on supported lipid bilayers composed of phosphatidylcholine (PC) and PS. Total internal reflection florescence (TIRF) microscopy with single particle tracking was used to identify diffusion constants of each individual or tandem C2 domain. Granuphilin C2A displays a lateral diffusion constant of ∼2 μm2/s when bound to 1:1 DOPC:DOPS bilayers, comparable to other C2 domains. However, the diffusion of the granuphilin C2AB tandem on the same membrane is significantly slower; suggesting substantial PS contacts for the C2B domain within the C2AB tandem. This effect represents a weak but potentially physiologically relevant interaction that influences the membrane-bound state of this strong membrane binding protein. In a separate experiment, we also show that the diffusion of the individual C2A domain decreases significantly in the presence of 2% phosphatidylinositol-(4,5)-bisphosphae (PIP2), suggesting separate binding sites for these two lipid ligands. Overall, single-molecule tracking can reveal membrane-binding states that are difficult to detect with traditional ensemble approaches.
Relationship between Teacher Fidelity and Physical Education Student Outcomes.

To evaluate the influence of scientifically based curricula intended for the physical education (PE) classroom, researchers should consider fidelity, or the extent to which teachers who are implementing a PE curricular intervention adhere to the model of curriculum and instruction inherent in the research design. The purpose of this study was to assess PE teachers’ fidelity of implementation as they implemented a research-based PE curricular intervention and to examine the relationship between teachers’ fidelity to the curricular intervention and student outcomes. Six teachers from three middle schools taught one 20-lesson unit from a PE intervention to their sixth grade students. Teachers’ fidelity of implementation was documented using nonparticipatory observations. Students’ knowledge acquisition was measured on a standardized knowledge test prior to and after the 20-lesson unit. Students’ physical activity intensity levels were measured on lesson observation days using accelerometers. Multiple regression with fidelity score as the predictor and knowledge acquisition as the criterion variable indicated that teachers’ fidelity scores accounted for a large portion of variance in student knowledge growth (R2 = .79, adj R2 = .74, p < .05). Approximately 48% of all observed lesson time involved moderate to vigorous physical activities. Based on the findings from this research, it appears the more faithful teachers are to teaching research-based curricula as designed, the greater the impact the curricula can have on student achievement.
Adverse weather conditions and fatal motor vehicle crashes in the United States, 1994-2012

Motor vehicle crashes are a leading cause of injury mortality. Adverse weather and road conditions have the potential to affect the likelihood of motor vehicle fatalities through several pathways. However, there remains a dearth of assessments associating adverse weather conditions to fatal crashes in the United States. We assessed trends in motor vehicle fatalities associated with adverse weather and present spatial variation in fatality rates by state. We analyzed the Fatality Analysis Reporting System (FARS) datasets from 1994 to 2012 produced by the National Highway Traffic Safety Administration (NHTSA) that contains reported weather information for each fatal crash. For each year, we estimated the fatal crashes that were associated with adverse weather conditions. We stratified these fatalities by months to examine seasonal patterns. We calculated state-specific rates using annual vehicle miles traveled data for all fatalities and for those related to adverse weather to examine spatial variations in fatality rates. To investigate the role of adverse weather as an independent risk factor for fatal crashes, we calculated odds ratios for known risk factors (e.g., alcohol and drug use, no restraint use, poor driving records, poor light conditions, highway driving) to be reported along with adverse weather. Total and adverse weather-related fatalities decreased over 1994–2012. Adverse weather-related fatalities constituted about 16 % of total fatalities on average over the study period. On average, 65 % of adverse weather-related fatalities happened between November and April, with rain/wet conditions more frequently reported than snow/icy conditions. The spatial distribution of fatalities associated with adverse weather by state was different than the distribution of total fatalities. Involvement of alcohol or drugs, no restraint use, and speeding were less likely to co-occur with fatalities during adverse weather conditions. While adverse weather is reported for a large number of motor vehicle fatalities for the US, the type of adverse weather and the rate of associated fatality vary geographically. These fatalities may be addressed and potentially prevented by modifying speed limits during inclement weather, improving road surfacing, ice and snow removal, and providing transit alternatives, but the impact of potential interventions requires further research.
Discretion in Social Services

This chapter describes the discretionary authority inherent in the operation of social services agencies. Discretion is the conditions imposed by social workers upon the recipients of social services. Discretion, however, is a matter of degree that manifests itself under varying circumstances. In some programs, rules are clear-cut and the choices allowed officials are minimal. However, such programs are relatively rare. In most programs, and especially in the social service programs, officials are allowed great latitude in imposing conditions as a part of the price for the delivery of social services. Understanding and controlling official discretion is the key legal issue in social services. It is discussed that the existence of widespread discretion does not lead to the conclusion that administrative behavior is completely unfettered. In social services, as in other administrative systems, there are constraints. Despite wide grants of authority, state, local, and private agencies will pick and choose among programs; some will be funded but not others. Also, there will be selections in eligibility rules and other conditions of aid. Administrators, supervisors, and caseworkers will also be constrained. They have professional and bureaucratic norms; they have their own sense of what is lawful and proper under the laws and regulations. In addition, the bargaining within and between agencies will constrain behavior. Discretion, then, is not boundless. However, the important point is that the constraints on discretion, for the most part, arise outside of the legal framework; they are not imposed by law and consequently will not serve as legal protections for aggrieved clients.