cssi/SciSciGPT-SciSciNet huggingface dataset:
Controlled release of vancomycin from thin sol-gel films on titanium alloy fracture plate material

Risk of infection is considerable in open fractures and its management is challenging, especially when fracture fixation material is used. Thus, it may be desirable to use a device from which antibiotics can be released in a controlled way. Room temperature processed silica sol-gels are novel, resorbable and biocompatible, controlled release materials. Vancomycin, a potent antibiotic used in treating osteomyelitis, can be released from silica sol-gels. Herein, we describe the synthesis of thin, resorbable, controlled release bactericidal sol-gel films on a Ti-alloy substrate and determine the effect of processing parameters on its degradation and vancomycin release. A close correlation between release and degradation rates suggests that film degradation is the main mechanism underlying the control of release. Using a multi-layer process and various concentrations of vancomycin, released concentrations exceed the minimal inhibitory concentration (MIC) of vancomycin against Staphylococcus aureus. The findings enable the tailoring of release and degradation properties of the films to therapeutic needs by controlling sol-gel processing parameters. Given the bactericidal properties of released vancomycin, and the biocompatibility of the sol-gel films, the present data suggest great promise to prevent and treat bone infections in a clinical setting.
Kinetics and Mechanism of Ketone Enolization Mediated by Magnesium Bis(hexamethyldisilazide)

Magnesium bis(hexamethyldisilazide), Mg(HMDS)(2), reacts with substoichiometric amounts of propiophenone in toluene solution at ambient temperature to form a 74:26 mixture of the enolates (E)- and (Z)-[(HMDS)(2)Mg(2)(mu-HMDS){mu-OC(Ph)=CHCH(3)}], (E)-1 and (Z)-1, which contain a pair of three-coordinate metal centers bridged by an amide and an enolate group. The compositions of (E)-1 and (Z)-1 were confirmed by solution NMR studies and also by crystallographic characterization in the solid state. Rate studies using UV-vis spectroscopy reveal the rapid and complete formation of a reaction intermediate, 2, between the ketone and magnesium, which undergoes first-order decay with rate constants independent of the concentration of excess Mg(HMDS)(2) (DeltaH++ = 17.2 +/- 0.8 kcal/mol, DeltaS++ = -11 +/- 3 cal/mol.K). The intermediate 2 has been characterized by low-temperature (1)H NMR, diffusion-ordered NMR, and IR spectroscopy and investigated by computational studies, all of which are consistent with the formulation of 2 as a three-coordinate monomer, (HMDS)(2)Mg{eta(1)-O=C(Ph)CH(2)CH(3)}. Further support for this structure is provided by the synthesis and structural characterization of two model ketone complexes, (HMDS)(2)Mg(eta(1)-O=C(t)Bu(2)) (3) and (HMDS)(2)Mg{eta(1)-O=C((t)Bu)Ph} (4). A large primary deuterium isotope effect (k(H)/k(D) = 18.9 at 295 K) indicates that proton transfer is the rate-limiting step of the reaction. The isotope effect displays a strong temperature dependence, indicative of tunneling. In combination, these data support the mechanism of enolization proceeding through the single intermediate 2 via intramolecular proton transfer from the alpha carbon of the bound ketone to the nitrogen of a bound hexamethyldisilazide.
On the extension problem for continuous positive definite Generalized Toeplitz Kernels definite on a finite interval

The extension problem for positive definite Generalized Toeplitz Kernels defined on a finite interval of the real axis is discussed. This problems contains the Krein's extension problem for a positive definite function as a particular case. Criteria of uniqueness of extension is obtained. All extension are described in a complitely indeterminate case.
Use of triple-lumen subclavian catheters for administration of total parenteral nutrition.

This study evaluated the safety of triple vs single-lumen catheters in intravenous nutrition. Patients who were judged likely to benefit from a triple-lumen catheter were randomized to receive either a single-lumen catheter, with additional peripheral or central venous access as needed, or a triple-lumen catheter. All patients were at increased risk of catheter-related infection because of one or more of the following conditions: > 60 years of age, breakdown of skin integrity, severe underlying illness, diagnosis of acute pancreatitis, recent head or neck surgery, or presence of a preexisting infection. Patients were excluded who had neutropenia, were immunosuppressed, had body burns > 40%, or had contaminated wounds in the subclavicular area. Of 204 patients entered between June 1989 and November 1991, 177 completed the required > or = 7 days of therapy. Seventy-eight of these patients were randomized to a single-lumen catheter and 99 to a triple-lumen catheter. Catheters were inserted and maintained by the Nutrition Support Team. Dressings were monitored daily and changed weekly using a bio-occlusive dressing. When parameters were met for a possible septic episode, simultaneous peripheral and central catheter blood cultures were obtained using the Isolator method. Catheter-related sepsis was considered present if the colony count from a central catheter lumen was > or = 5 times that of the peripheral blood. The incidence of catheter-related sepsis for single-lumen catheters was 2.6% (2 of 78) compared with 13.1% for triple-lumen catheters (13 of 99) (p < .01). No correlation was found with the number of insertion attempts, catheter days, or patient's age.(ABSTRACT TRUNCATED AT 250 WORDS)
Prospective, randomized, double-blind study of prophylactic antibiotics in axillary lymph node dissection.

Abstract Background: Antibiotic prophylaxis is controversial in patients undergoing axillary lymph node dissection (ALND). We determined whether preoperative antibiotics decreased incidence or treatment cost of infectious complications following ALND. Methods: Two hundred patients entered this prospective, randomized, double-blind trial. Patients received either placebo or cefonicid preoperatively. Loco-regional signs of infection were monitored for 4 weeks postoperatively. Results: There was a trend toward fewer infections in the prophylactic group (placebo 13% versus cefonicid 6%; P = 0.080). Cefonicid significantly decreased severe infections requiring hospitalization (placebo 8% versus cefonicid 1%; P = 0.033). Cefonicid also decreased the treatment cost of infection per patient ($49.80 versus $364.87). Conclusions: We demonstrated a trend toward fewer overall infections and significantly fewer severe infections in patients given prophylactic antibiotics, which translated into a decrease in the cost of treatment for infectious complications. These findings support antibiotic prophylaxis for patients undergoing ALND.
Cell transformation: a missed opportunity

Neoplastic and Normal Cells in Culture. Developmental and Cell Biology, 8. ByJ.M. Vasiliev andI.M. Gelfand. Pp.372. ISBN 0-521-23149-3. (Cambridge University Press: 1981.) £40, $79.50.
Stiles-Crawford effect of the first kind: assessment of photoreceptor alignments following dark patching.

Abstract Properties of presumed mechanisms controlling photoreceptor alignments are partially defined. A phototropic mechanism normally dominates alignment, but do modest changes in orientations occur with dark patching? Here, new photopic Stiles–Crawford (SCE-I) determinations were made before patching (pre-patch), just after 8-days of dark-patching (post-patch), and 3 days after patch removal (recovery test). We tested at 0, 11 and 22° in the temporal retina of both eyes. Ten eyes of adult subjects were tested. SCE-I peak positions and Stile's parameter ‘rho’ were assessed. Dark-patching effects were small. Observations revealed meaningful corrective alignment overshoots with recovery in the light. Results suggest (1) the presence of multiple weak mechanisms affecting receptor alignments in the dark; (2) the phototropic mechanism to be dominant in the light; (3) the need for multiple test loci to be sampled in such studies, and (4) small changes in the SCE-I in the pupil plane can reflect meaningful events occurring at the retina.
Designing sustainable revenue models for CHW-centric entrepreneurial ventures

Developing countries around the world have implemented Community Health Worker (CHW) programs to improve community health through education, advocacy and direct assistance. CHWs have repeatedly proven their ability to mitigate the growing double disease burden of infectious and chronic illnesses. At the same time, a lack of tangible incentives for CHWs leads to high attrition rates, poor efficiency and lack of coordination and accountability. In the quest for transforming CHWs from volunteers to entrepreneurs, a typology of eight business models where CHWs function as the channels and champions for global health projects has been articulated. In parallel, the literature on the failure modes of telemedicine, eHealth and mHealth ventures is gradually growing and providing new insights and practical design lessons. This article synthesizes the business models and failure modes, i.e. it discusses the primary failure modes for each of the eight business models for sustainable CHW projects and programs. This knowledge is pivotal for innovators and entrepreneurs seeking to engage local entrepreneurs and CHWs to operationalize interventions that tackle last mile health care challenges while creating jobs or providing frameworks for income generation and entrepreneurship.
Blood alcohol concentration: A critical factor for producing fetal alcohol effects

A dose of 6.6 g/kg of alcohol, delivered in 12 equally-spaced fractions each 24 hours via an artificial rearing procedure during postnatal days 4-10, produced mean blood alcohol concentrations (BACs) that were low (46.6 mg/dl), but stable with time. This relatively constant alcohol exposure did not limit brain growth in neonatal rats when measured on postnatal day 10. The same daily dose concentrated into 6 fractions over 12 hours (with 6 alcohol-free fractions the remaining 12 hours) resulted in cyclic BACs having high peaks (270.2 mg/dl). The cyclic regimen produced a significant reduction in brain growth. Thus, the peak blood alcohol concentration is a critical factor in determining the minimum dose for producing microencephaly and must be considered when estimating the relative teratogenic risks of alcohol intake during pregnancy.
USING SOCIAL NETWORK INTERVENTIONS TO IMPROVE MENTALLY ILL CLIENTS’ WELL-BEING

This paper reviews empirical evidence showing that the structures of the social networks of mentally ill clients influence both their well-being and their use of mental health services. Network interventions that might help clients better address network-related problems, and might help their families improve relationships and prevent caretaker’s burn-out are presented. A case illustration will demonstrate how practitioners can assess a client’s social network, involve the client’s family in treatment, evaluate that treatment, and select tailored interventions. This case will emphasize both how practitioners can help a client restructure her network, and the complementary roles of formal and informal networks. The author shows practitioners how to match clients’ initial network structures to interventions and desired outcomes. Practitioners can thus help clients modify their social networks, increase the use of preventive services, and improve their well-being.
On the rate and uniformity of CdTe deposition in an impinging jet reactor: numerical simulations

Abstract The impinging jet with a parabolic inlet profile was modeled numerically and the results were compared to an existing series solution. The results at nozzle heights of 0.5 radii and above agreed within 1% of the series solution, but discrepancies of several percent were obtained at nozzle heights below 0.375 radii where the series solution did not converge well. Numerical solutions that allowed for thermal gradients, details of an actual impinging jet reactor, and cadmium telluride deposition from organometallic precursors, were also obtained. The experimentally-derived mass-transfer-limited deposition profile and the model simulations agreed when the model's concentrations at the bubbler outlets were reduced by a factor of four from the saturation values. This correction was justified when an inventory of reactant revealed that the mixtures at the bubbler outlets were far from saturated.
Medial Nucleus of the Amygdala Mediates Chemosensory Control of Male Hamster Sexual Behavior

Bilateral lesions restricted to the medial nucleus of the amygdala eliminate mating behavior in the male hamster and severely diminish the male's sniffing and licking investigation of the female hamster's anogenital region. The results suggest that olfactory and vomeronasal sensory information critical to male mating behavior is processed in the medial nucleus, which is an androgen-binding brain area. Thus the medial nucleus may act as a relay through which chemosensory information influences activity in the medial preoptic-anterior hypothalamic junction and the bed nucleus of the stria terminals, areas important in the mediation of male sexual behavior.
FK506-Induced Fulminant Leukoencephalopathy After Single-Lung Transplantation

FK506 is being used increasingly to prevent rejection after organ transplantation. Its use is associated with a wide spectrum of neurotoxicity, which has been described after most solid organ transplantations, but reports after lung transplantation are extremely rare. This is a report of the pathologic correlation of the clinical and radiologic features of delayed FK506-induced fulminant leukoencephalopathy after single-lung transplantation. The patient presented with neurologic symptoms that progressed to seizure activity. Neuroimaging showed diffuse changes in the brain, and results of a brain biopsy were consistent with leukoencephalopathy with microglial and astrocytic activation. The patient had a remarkable improvement in clinical status after discontinuation of FK506 administration, with resolution of the changes seen on neuroimaging.
Spinal and supraspinal factors in voluntary movement.

Abstract During a rapid voluntary movement, the agonist muscle produces two distinct volleys of EMG activity separated by a period of relative electrical silence. Human subjects were instructed to adduct their arm against the load of a spring, and this EMG pattern was recorded from the pectoralis major. When the limb was unloaded during movement, the second burst of EMG activity was significantly reduced in size. However, when the agonist was shortened passively just prior to movement, the size of the first burst was not affected. The results suggest that movement is initiated by direct corticospinal drive of the main motoneurons, while spinal reflexes become more important later in the move.
Nanostructured materials for electrochromic devices

Abstract Five types of nanostructured films produced by a sol–gel method were investigated to enhance the electrochemical, optical, and mechanical properties of electrochromic tungsten oxide films. WO 3 films containing SiO 2 and TiO 2 nanoparticles offered promising results of high coloration density and fast response time. The film based on WO 3− x –0.1TiO 2− y sol–gel solution mixed with oxalic acid was found to be stable and has excellent characteristics in coloring/bleaching kinetics.
Metabolic and nutritional support of the enterocutaneous fistula patient: a three-phase approach.

The care and outcome of enterocutaneous fistula (ECF) have improved greatly over several decades due to revolutionary advances in nutrition, along with dramatic improvements in the treatment of sepsis and the critically ill. However, as the collective experience with damage control surgery has matured, the frequent development of enteroatmospheric fistula (EAF) in the “open abdomen” patient has emerged as an even more vexing problem. Despite our best efforts, ECF and especially EAF continue to be highly morbid conditions, and sepsis and malnutrition remain the leading causes of death. Aggressive nutritional and metabolic support is the most significant predictor of outcome with ECF and EAF. Discussion of the historical advances in nutritional therapy and their impact on ECF, as well as review of the classification of ECF and EAF, provides a framework for the suggested phased strategy that specifically targets the nutritional and metabolic needs of the ECF/EAF patient. These three phases include (1) diagnosis, resuscitation, and early interval nutrition; (2) definition of fistula anatomy, drainage of collections, nutritional assessment and monitoring, and placement of feeding access; and (3) definitive nutritional management, including pharmacologic adjuncts. Early nutritional support with parenteral nutrition followed by transition to enteral nutrition is advocated, including the merits of delivery of enteral nutrition via the fistula itself, known as fistuloclysis. Aggressive nutritional therapy is necessary to reverse the catabolic state associated with ECF/EAF patients. Once established, it allows proper time, preparation, and planning for definitive management of the fistula, and in many cases provides the support for spontaneous closure.
A Rhabdomyoma Within a Multilocular Thymic Cyst in a p53-Null Mouse

A 9-month-old p53-null female mouse was found dead in its cage. At necropsy, a large thymic mass encompassed the heart. Microscopically, the mass was composed of numerous varying-sized cysts lined with simple squamous epithelial cells to columnar ciliated cells. Also present within this mass was a large aggregate of loosely arranged fusiform-shaped cells. These cells also were found in smaller numbers in the connective tissue surrounding the cysts. The larger aggregate of fusiform cells was positive for desmin and S-100 and negative for smooth muscle actin. Electron microscopy revealed well-formed Z lines and I bands of skeletal muscle phenotype. A diagnosis of rhabdomyoma within a congenital multilocular thymic cyst was made. The thymus contains a small population of myoid cells, which should be taken in consideration when evaluating thymic tumors.
The Sensitivity to Parametric Variation in Direct Minimization Techniques

Solutions of some objective analysis techniques are known to depend upon the subjective values of internal parameters. The change in the solution per change in the parameter is the sensitivity. Parameters with low sensitivity can be varied with large increments during preliminary searches for near-optimal parameter values. Only terms with high sensitivity must be thoroughly investigated once the parameters are determined to be close to optimal. Both absolute and relative sensitivities are discussed and a sensitivity-based definition of the solution uncertainty is proposed. The sensitivity of direct minimization analysis to parametric variation is evaluated using a set of 'response functions' that characterize different aspects of the solution. It is shown that solutions of direct minimization techniques have low absolute sensitivity. Two examples are used to illustrate the usefulness of the technique. Both involved measurements of air-sea quantities (e.g., wind stress and latent heat flux) from a variety of data sources using a direct minimization technique. The examples demonstrate that sensitivity analysis is capable of quantifying regional sensitivities as well as indicating the magnitude and relationship between the various parameters.
Expression of Nestin by Neural Cells in the Adult Rat and Human Brain

Neurons and glial cells in the developing brain arise from neural progenitor cells (NPCs). Nestin, an intermediate filament protein, is thought to be expressed exclusively by NPCs in the normal brain, and is replaced by the expression of proteins specific for neurons or glia in differentiated cells. Nestin expressing NPCs are found in the adult brain in the subventricular zone (SVZ) of the lateral ventricle and the subgranular zone (SGZ) of the dentate gyrus. While significant attention has been paid to studying NPCs in the SVZ and SGZ in the adult brain, relatively little attention has been paid to determining whether nestin-expressing neural cells (NECs) exist outside of the SVZ and SGZ. We therefore stained sections immunocytochemically from the adult rat and human brain for NECs, observed four distinct classes of these cells, and present here the first comprehensive report on these cells. Class I cells are among the smallest neural cells in the brain and are widely distributed. Class II cells are located in the walls of the aqueduct and third ventricle. Class IV cells are found throughout the forebrain and typically reside immediately adjacent to a neuron. Class III cells are observed only in the basal forebrain and closely related areas such as the hippocampus and corpus striatum. Class III cells resemble neurons structurally and co-express markers associated exclusively with neurons. Cell proliferation experiments demonstrate that Class III cells are not recently born. Instead, these cells appear to be mature neurons in the adult brain that express nestin. Neurons that express nestin are not supposed to exist in the brain at any stage of development. That these unique neurons are found only in brain regions involved in higher order cognitive function suggests that they may be remodeling their cytoskeleton in supporting the neural plasticity required for these functions.
Hydrostatic Gas Bearings

Orifice-regulated hydrostatic gas bearings offer significant advartages for instrument applications. In particular, gimbal bearings for inertial guidance systems can be designed with negligible starting torque and high stiffness, and for operation at extreme temperatures. Based on Euler's equation, expressions for the significant parameters, i.e., pressure profile, gas-flow rate, gap height, and loadcarrying capacity of pad and step bearings, are developed. These parameters yield results which are in excellent agreement with experimental data. The test fixture incorporates pneumatic loading by means of a bellows-suspended piston which is prevented from cocking by an air bearing. (auth)
Single-institution experience with interhospital extracorporeal membrane oxygenation transport: A descriptive study.

Objective Patients with refractory cardiopulmonary failure may benefit from extracorporeal membrane oxygenation, but extracorporeal membrane oxygenation is not available in all medical centers. We report our institution's nearly 20-yr experience with interhospital extracorporeal membrane oxygenation transport. Design Retrospective review. Setting Quaternary care children's hospital. Patients All patients undergoing interhospital extracorporeal membrane oxygenation transport by the Arkansas Children's Hospital extracorporeal membrane oxygenation team. Interventions Data (age, weight, diagnosis, extracorporeal membrane oxygenation course, hospital course, mode of transport, and outcome) were obtained and compared with the most recent Extracorporeal Life Support Organization Registry report. Results Interhospital extracorporeal membrane oxygenation transport was provided to 112 patients from 1990 to 2008. Eight were transferred between outside facilities (TAXI group); 104 were transported to our hospital (RETURN group). Transport was by helicopter (75%), ground (12.5%), and fixed wing (12.5%). No patient died during transport. Indications for extracorporeal membrane oxygenation in RETURN patients were cardiac failure in 46% (48 of 104), neonatal respiratory failure in 34% (35 of 104), and other respiratory failure in 20% (21 of 104). Overall survival from extracorporeal membrane oxygenation for the RETURN group was 71% (74 of 104); overall survival to discharge was 58% (61 of 104). Patients with cardiac failure had a 46% (22 of 48) rate of survival to discharge. Neonates with respiratory failure had an 80% (28 of 35) rate of survival to discharge. Other patients with respiratory failure had a 62% (13 of 21) rate of survival to discharge. None of these survival rates were statistically different from survival rates for in-house extracorporeal membrane oxygenation patients or for survival rates reported in the international Extracorporeal Life Support Organization Registry (p > .1 for all comparisons). Conclusions Outcomes of patients transported by an experienced extracorporeal membrane oxygenation team to a busy extracorporeal membrane oxygenation center are very comparable to outcomes of nontransported extracorporeal membrane oxygenation patients as reported in the Extracorporeal Life Support Organization registry. As has been previously reported, interhospital extracorporeal membrane oxygenation transport is feasible and can be accomplished safely. Other experienced extracorporeal membrane oxygenation centers may want to consider developing interhospital extracorporeal membrane oxygenation transport capabilities to better serve patients in different geographic regions.
Family perceptions of facilitators and inhibitors of effective school-based dysphagia management.

Purpose This qualitative study focused on the perceptions of family members of children with dysphagia by asking what the family-identified factors are that facilitate or inhibit effective school-b...
Scaling the effects of moose browsing on forage distribution, from the geometry of plant canopies to landscapes

Landscape heterogeneity influences large herbivores by altering their feeding rates, but as herbivores attempt to maximize feeding rates they also create spatial heterogeneity by altering plant growth. Herbivore feeding rates thus provide a quantitative link between the causes and consequences of spatial heterogeneity in herbivore-dominated ecosystems. The fractal geometry of plant canopies determines both the density and mass of twigs available to foraging herbivores. These properties determine a threshold distance between plants (d*) that distinguishes the mechanisms regulating herbivore intake rates. When d* is greater than the actual distance between plants (d), intake is regulated by the rate of food processing in the mouth. But when d* < d, intake is regulated by the rate at which the herbivore encounters new plants. Alterations to plant geometry due to past browsing could change the rate at which herbivores encounter and process bites of plant tissue, modify d* relative to d, and thus change intake...
Threshold temperatures for solute mobility. Their determination and effect on programmed temperature gas chromatographic separations

The threshold temperature for solute mobility is defined as that temperature at which a solute band, which was initially cold trapped at the head of the column, begins moving through the column. It is shown that the separation of compounds by programmed temperature gas Chromatography (PTGC) occurs primarily at the head of the column as a result of differences in threshold temperatures. Additional column length beyoud that needed to trap the compounds improves resolution, primarily by delaying emergence (while maintaining the temperature and time spacing) thus allowing the column temperature to rise, the solute terminal velocities to increase, and narrower peak widths to be recorded. For maximum resolution in minimum analysis time, the initial temperature must be at or below the threshold temperature of the most volatile compound in the mixture to be separated. Three methods for determining threshold temperatures are presented.
Nuclear Medicine and the Infected Joint Replacement

Nearly 700,000 hip and knee arthroplasties are performed annually in the United States. Although the results in most cases are excellent, implants do fail. Complications like heterotopic ossification, fracture, and dislocation are now relatively rare and easily diagnosed. Differentiating aseptic loosening, the most common cause of prosthetic joint failure, from infection, is important because their treatments are very different. Unfortunately, differentiating between these 2 entities can be challenging. Clinical signs of infection often are absent. Increased peripheral blood leukocytes, erythrocyte sedimentation rate, and C-reactive protein levels are neither sensitive nor specific for infection. Joint aspiration with Gram stain and culture is the definitive diagnostic test. Its specificity is in excess of 90%; its sensitivity is variable, however, ranging from 28% to 92%. Plain radiographs are neither sensitive nor specific and cross-sectional imaging modalities, such as computed tomography and magnetic resonance imaging, can be limited by hardware-induced artifacts. Radionuclide imaging is not affected by orthopedic hardware and is the current imaging modality of choice for suspected joint replacement infection. Bone scintigraphy is sensitive for identifying the failed joint replacement, but cannot be used to determine the cause of failure. Neither periprosthetic uptake patterns nor performing the test as a 3-phase study significantly improve accuracy, which is only about 50-70%. Thus, bone scintigraphy typically is used as a screening test or in conjunction with other radionuclide studies. Combined bone gallium imaging, with an accuracy of 65-80%, offers only modest improvement over bone scintigraphy alone. Presently, combined leukocyte/marrow imaging, with approximately 90% accuracy, is the radionuclide imaging procedure of choice for diagnosing prosthetic joint infection. In vivo leukocyte labeling techniques have shown promise for diagnosing musculoskeletal infection; their role in prosthetic joint infection has not been established. 111 In-labeled polyclonal immunoglobulin lacks specificity. 99m Tc-ciprofloaxicin does not consistently differentiate infection from aseptic inflammation. 18 F-fluorodeoxyglucose positron emission tomography has been extensively investigated; its value in the diagnosis of prosthetic joint infection is debatable.
Distribution of DDT in brain and spinal cord of the rat

Abstract The distribution of DDT in the neocortex, cerebellum, brain stem, remaining brain, spinal cord, liver, and plasma of the rat was determined 6, 12, and 24 hours after a single dose per os of 100 mg/kg DDT in oil. The results showed that lipids in central nervous system (CNS) areas which are mostly gray matter, such as neocortex and cerebellum, take up DDT rather rapidly and attain a relatively high maximal concentration. Lipids in areas which have a high myelin content, such as brain stem and spinal cord, take up DDT more slowly and reach a relatively lower maximal concentration. DDT concentrations in lipids of whole brain were twice as high as in the spinal cord lipids at 6 and 12 hours, but were about the same at 24 hours. When DDT concentrations were expressed per unit fresh weight, rather than per unit lipid weight, the concentrations were the same in brain and spinal cord at 6 and 12 hours, but were twice as high in the spinal cord as in the brain at 24 hours. One possible relation between the symptoms of DDT poisoning and the distribution of DDT in the CNS is discussed.
Radiation-induced errors in memory chips

We have measured probabilities for proton, neutron and pion beams from accelerators to induce temporary or soft errors in a wide range of modern 16 Mb and 64 Mb DRAM memory chips, typical of those used in aircraft electronics. Relations among the cross sections for these particles are deduced. Measurement of alpha particle yields from pions on aluminum, as a surrogate for silicon, indicate that these reaction products are the proximate cause of the charge deposition resulting in errors.
Emerging telecommunication technologies

The authors address the emerging telecommunications technologies that have been introduced into the marketplace and that are being used by businesses to gain a competitive edge by reducing costs and improving operating efficiency. It is noted that these technologies can be used by educators as well to strategically access information, to gain a competitive edge, to enhance teaching effectiveness, and to increase the technological literacy of today's students. The effect these technologies may have on the educational process is examined. Each technology is described with a basic explanation, the current status, and a discussion of educational applications. The goal of the present work is to enhance educator's awareness of this technology and to improve their ability to plan for its use in the classroom. >
Shifting Least Restrictive Environments in a Large Urban School District.

This study examined the efforts of one large urban school district to implement support to schools in increasing their rates of students being served in inclusive settings. The authors evaluate a process whereby the district used a self-created LRE/Achievement at a Glance Tool to measure programs, services, and learner outcomes for students with disabilities, and provide specific recommendations and supports to administrative teams in targeted schools. Results indicate statistically significant increases in the number of students who were fully included as well as statistically significant increases in average time students with disabilities spent with their nondisabled peers. Math and reading proficiency levels for students with and without disabilities are also reported. Implications for best practices in supporting inclusion in urban districts are examined, such as the importance of documenting and examining inclusive practices and further training for educators and administrators in ethical principles and practice.
The transcription factors Etv4 and Etv5 mediate formation of the ureteric bud tip domain during kidney development

Signaling by the Ret receptor tyrosine kinase promotes cell movements in the Wolffian duct that give rise to the first ureteric bud tip, initiating kidney development. Although the ETS transcription factors Etv4 and Etv5 are known to be required for mouse kidney development and to act downstream of Ret, their specific functions are unclear. Here, we examine their role by analyzing the ability of Etv4 Etv5 compound mutant cells to contribute to chimeric kidneys. Etv4−/−;Etv5+/− cells show a limited distribution in the caudal Wolffian duct and ureteric bud, similar to Ret−/− cells, revealing a cell-autonomous role for Etv4 and Etv5 in the cell rearrangements promoted by Ret. By contrast, Etv4−/−;Etv5−/− cells display more severe developmental limitations, suggesting a broad role for Etv4 and Etv5 downstream of multiple signals, which are together important for Wolffian duct and ureteric bud morphogenesis.
ATR-FTIR Spectroscopic Investigation on Phosphate Adsorption Mechanisms at the Ferrihydrite-Water Interface

Abstract We investigated the phosphate(P) adsorption mechanisms at the ferrihydrite–water interface as a function of pH, ionic strength (I), and loading level, using a combination of adsorption envelopes, electrophoretic mobility (EM) measurements, and attenuated total reflectance Fourier transform infrared (ATR–FTIR) spectroscopy. The P adsorption envelopes show that: (1) adsorption decreases with increasing pH 3.5–9.5 and (2) adsorption is insensitive to changes in I at pH 4–7.5, but it slightly increases with increasing I from 0.01 to 0.8 at pH>7.5. The EM in 0.1 M NaCl decreases with increasing P concentration from 0 to 50 μmol L−1 at pH 3–9. The results of these macroscopic studies suggest the formation of inner-sphere complexes. The ATR–FTIR investigation shows that inner-sphere surface complexes are nonprotonated, bidentate binuclear species (≡Fe2PO4) at pH≥7.5 and could be associated with Na+ ions at P loading levels of 0.38 μmol m−2. At pH 4–6, protonated inner- sphere complexes are proposed at the loading levels between 0.38 and 2.69 μmol m−2.
Parties, Unions, Policies and Occupational Sex Segregation in the United States

We utilize the 2000 Equal Employment Opportunity file of the U.S. Census and various secondary resources to determine if party control, union density and states' anti-discrimination and family leave policy legacies affect levels of occupational sex segregation across large counties. Our findings offer a puzzle to political sociologists because two theories that are typically pitted against one another (Power Resource Theory vs. Liberal Economic Theory) predict and result in comparable outcomes. Indeed, as suggested by Social Democratic Theory, the sub-national United States have lower levels of occupational sex segregation when the Democratic Party and unions are strong, and policies are the mechanism through which these states maintain low occupational sex segregation. Yet, interestingly, as suggested by Liberal Economic Theory, occupational sex segregation is also low when unions and the Democratic Party are both weak, suggesting that unfettered market capitalism redresses socio-economic inequalities.
Limited Grooming Architectures and Groomer-port Placement in Optical WDM Mesh Networks

In this paper, we consider the problem of traffic grooming in optical wavelength division multiplexed (WDM) mesh networks under static traffic conditions. The objective of this work is to minimize the network cost and in particular, the electronic port costs incurred for meeting a given performance goal. In earlier work, we have shown the benefits of limited grooming switch architectures, where only a subset of wavelengths in a network are equipped with expensive SONET Add Drop Multiplexers (SADM) that provide the grooming functionality. In this work, we also consider the wavelength conversion capability of such groomers. This can be achieved using a digital cross-connect (DCS) in the grooming switch to switch low-speed connections between the SADMs (and hence, between wavelengths). The grooming switch thus avoids the need for expensive optical wavelength converters. Based on these observations, we propose a limited conversion based grooming architecture for optical WDM mesh networks. The local ports at every node in this architecture can be one of three types: an add- drop port, a grooming port that allows wavelength conversion or a grooming port that does not allow wavelength conversion. The problem studied is: given a static traffic model, where should the different ports be placed in a network? We formulate this as an optimization problem using an Integer Linear Programming (ILP) and present numerical results for the same. We also present a heuristic based approach to solve the problem for larger networks.
Enzyme Inhibitors XIV: Syntheses of Some 9-(m-Substituted Benzyl)-6-substituted Purines and Their Evaluation as Inhibitors of Adenosine Deaminase

Recent studies have shown that 9-( p -bromoacetamidobenzyl)adenine is an irreversible inhibitor of adenosine deaminase. In order to study the effect of isomers on the inhibition of adenosine deaminase, a variety of reversible inhibitors of adenosine deaminase have been synthesized which are 9-( m -substituted benzyl)-6-substituted purines. In addition, it was found that 9-( m -bromoacetamidobenzyl)adenine is an irreversible inhibitor of adenosine deaminase, but the rate of irreversible inactivation by the meta derivative was lower than that by the corresponding para isomer. This decreased rate of irreversible inhibition by 9-( m -bromoacetamidobenzyl)-adenine may be rationalized by assuming that in the reversible E…I complex the alkylating group is not positioned as near a nucleophilic group on the enzyme as it is in the case of the corresponding para isomer or that the meta derivative alkylates a different amino acid on the enzyme than does 9-( p -bromoacetamidobenzyl)adenine.
Wetlands Protection--A Goal Without a Statute

The difficulties encountered in applying the Clean Water Act over the past twenty-five years provide valuable insight into the regulatory mismatch problem. The idea that a Congressional determination that wetlands must be preserved, not only for scientific, but also for aesthetic and ethical reasons, would provide a constitutional basis for wetlands legislation, is examined in this paper. The difficulties encountered when basing law on an ambiguous scientific basis are also examined and certain solutions are considered. The concept of returning to the original intent of Congress through examination of the Clean Water Act's legislative history regarding the delegation of authority to the states is also considered. Finally, the movement of federal permit programs to state implementation (similar to the NPDES permitting program), as originally intended by the legislators, is examined.
Triple labral lesions: Pathology and surgical repair technique—report of seven cases

Purpose: The purpose of this article is to describe the pathology and operative treatment of triple labral lesions. Type of Study: Retrospective review. Methods: From June 1998 to June 2001, 297 patients underwent surgery by the senior author for lesions of the glenoid labrum. Of these, 7 patients (2.4%) had combined lesions of the anterior, posterior, and superior labrum. All patients were male with a mean age of 25 ± 7.3 years. All had a traumatic onset of symptoms. There were 4 dominant and 3 nondominant shoulders. Two patients had previously undergone surgery for instability. Each patient's primary complaint was instability and apprehension in the abducted and externally rotated position. No patient complained of posterior instability, although 3 patients had physical examinations suggestive of excessive posterior laxity. All patients underwent arthroscopic surgery following failure of conservative management. Results: All patients had distinct anterior labrum, posterior labrum, and type II SLAP lesions. All anterior and posterior labrum injuries were Bankart type except one. Two patients had complete circumferential detachment of the labrum and the other 5 patients had a small portion of the labrum still attached. Six patients had a Hill-Sachs lesion and 1 patient had a reverse Hill-Sachs lesion. All were nonengaging Hill-Sachs lesions. All patients were treated with suture anchor fixation of the torn labrum to bone. The median number of anchors used for fixation was 7 (range, 5 to 9 anchors). All patients were treated with a standardized postoperative rehabilitation protocol. At latest follow-up, 6 of 7 patients were satisfied with the procedure. There were no cases of recurrent instability. One patient developed post-traumatic osteoarthritis and underwent a second arthroscopic procedure and subsequently required hemiarthroplasty. This patient was dissatisfied with his result. Conclusions: Triple labral lesions represent an uncommon combination of lesions of the glenoid labrum. The majority of cases are likely secondary to primary anterior instability. Arthroscopic repair of triple labral lesions using suture anchor fixation to bone, although difficult and time consuming, can restore normal stability to the glenohumeral joint. The long-term outcome of these severe labral lesions remains to be determined, particularly with respect to the development of post-traumatic osteoarthritis. Level of Evidence: Level IV. Case series, no or historical control group.
Preference-based quality-of-life measures for neocortical epilepsy surgery.

SUMMARY Critical to decision analysis studies are measures of outcome utilities. In epilepsy surgery the benefit versus risk ratio is of particular interest in neocortical resections. Using the standard gamble, we measured preferences of 30 epilepsy patients for 10 outcome states specific to neocortical epilepsy surgery. Although considered preliminary, the findings suggest that the value of being seizure-free may be greater than that of continued disabling seizures, even if some deficits typical of ‘‘eloquent’’ cortex injury are incurred with surgery. Seizure freedom achieved with polytherapy medical management may be less desirable than that achieved with surgery and monotherapy.
Causes and Timing of Death in Extremely Premature Infants from 2000 through 2011

Background Understanding the causes and timing of death in extremely premature infants may guide research efforts and inform the counseling of families. Methods We analyzed prospectively collected data on 6075 deaths among 22,248 live births, with gestational ages of 22 0/7 to 28 6/7 weeks, among infants born in study hospitals within the National Institute of Child Health and Human Development Neonatal Research Network. We compared overall and cause-specific in-hospital mortality across three periods from 2000 through 2011, with adjustment for baseline differences. Results The number of deaths per 1000 live births was 275 (95% confidence interval [CI], 264 to 285) from 2000 through 2003 and 285 (95% CI, 275 to 295) from 2004 through 2007; the number decreased to 258 (95% CI, 248 to 268) in the 2008–2011 period (P=0.003 for the comparison across three periods). There were fewer pulmonary-related deaths attributed to the respiratory distress syndrome and bronchopulmonary dysplasia in 2008–2011 than in 2000...
Comparison of type 1, type 2, and atypical ketosis-prone diabetes at 4 years of diabetes duration.

Context: Atypical ketosis-prone diabetes (KPD) is frequently detected in obese individuals at diagnosis of diabetes, yet its precise pathophysiology is not understood. Aim: The hypothesis tested in this study states that while individuals with atypical KPD are phenotypically similar to those with type 2 diabetes, metabolically, they behave more like individuals with autoimmune type 1 diabetes. Methods: Thirty-seven individuals of Black, Hispanic, or White background and a diagnosis of diabetes mellitus for an average duration of 4 years participated in this cross-sectional study. Ten, 12, and 15 subjects had type 1, atypical, and type 2 diabetes, respectively. Insulin secretion was evaluated by a mixed-meal test. Insulin sensitivity and fuel oxidation were assessed by simultaneous euglycemic hyperinsulinemic clamp and indirect calorimetry. Lastly, a 12-h insulin withdrawal test was performed. Results: Insulin secretion, insulin sensitivity, and the insulin withdrawal tests yielded significant differences for type 1 vs. atypical diabetes and type 1 vs. type 2 diabetes, while there were no significant differences between atypical vs. type 2 diabetes. The indirect calorimetry showed higher-than-normal basal nonprotein respiratory quotients (RQs) and lower-than-normal insulin-stimulated nonprotein RQs across the three study groups. Conclusions: After 4 years from diabetes diagnosis and while far from optimal glycemic control, atypical KPD resembles type 2 diabetes phenotypically and metabolically as well. Therefore, this study supports the classification of atypical KPD as ketosis-prone type 2 diabetes, and the concept that metabolic inflexibility occurs in the presence of insulin resistance in type 1 and type 2 diabetes.
Review article: Thrombocytopenia in chronic liver disease

Summary Background Thrombocytopenia is a common finding in advanced liver disease. It is predominantly a result of portal hypertension and platelet sequestration in the enlarged spleen, but other mechanisms may contribute. The liver is the site of thrombopoietin (TPO) synthesis, a hormone that leads to proliferation and differentiation of megakaryocytes and platelet formation. Reduced TPO production further reduces measurable serum platelet counts. Aim This paper describes the scope of thrombocytopenia in chronic liver disease and assesses the clinical impact in this patient population. Methods A medline review of the literature was performed pertaining to thrombocytopenia and advanced liver disease. This data is compiled into a review of the impact of low platelets in liver disease. Results The incidence of thrombocytopenia, its impact on clinical decision making and the use of platelet transfusions are addressed. Emerging novel therapeutics for thrombocytopenia is also discussed. Conclusions Thrombocytopenia is a common and challenging clinical disorder in patients with chronic liver disease. New therapeutic options are needed to safely increase platelet counts prior to invasive medical procedures as well as to counteract therapies that further exacerbate low platelets, such as interferon. An ideal compound would be orally available and safe, with rapid onset of action.