cssi/SciSciGPT-SciSciNet huggingface dataset:
Minimally invasive resection of benign gastric tumors in challenging locations: prepyloric region or gastroesophageal junction.

Abstract Benign gastric tumors in a prepyloric location or within 3 cm adjacent of the gastroesophageal junction (GEJ) are often challenging to resect using minimally invasive surgical techniques. The aim of this study was to examine the outcomes of patients who underwent minimally invasive enucleation or resection of benign gastric tumors at these difficult locations. The charts of patients undergoing minimally invasive resection of benign-appearing submucosal gastric tumors between June 2001 and December 2012 were reviewed. Data on tumor size and location, type of minimally invasive surgical resection, perioperative complications, 90-day mortality, pathology, and recurrence were collected. A total of 70 consecutive patients underwent laparoscopic resection of benign-appearing submucosal gastric tumors; there were 24 patients with lesions close to the GEJ and nine patients with lesions close to the prepyloric region. All lesions were successfully resected laparoscopically. For prepyloric tumors, surgical approaches included enucleation (n = 1), wedge resection (n = 2), and distal gastrectomy with reconstruction (n = 6). For tumors close to the GEJ, surgical approaches included enucleation (n = 16), wedge resection (n = 3), and esophagogastrectomy (n = 5). Complications in this series of 33 patients included late strictures requiring endoscopic dilation in three patients who underwent esophagogastrectomy. The 90-day mortality rate was zero. There were no recurrences over a mean follow-up of 15 months (range, 1 to 86 months). Minimally invasive enucleation or formal anatomic resection of submucosal tumors located adjacent to the GEJ or at the prepyloric region is safe and carries a low risk for tumor recurrence. Submucosal gastric lesions adjacent to the GEJ are amenable to laparoscopic enucleation or wedge resection unless they extend proximally into the esophagus. Prepyloric lesions often require formal anatomic resection with reconstruction.
Pulmonary Atresia with Intact Ventricular Septum (PA/IVS)

Because some of the technical details of this procedure are different from those described in the section on critical PS, PA/IVS is described separately. Patients with short-segment (membrane-like) pulmonary atresia are cyanotic at birth and require PGE for maintenance of pulmonary blood flow. This is perhaps the most straightforward example of ductal-dependant pulmonary blood flow. Among those with PA/IVS there is a spectrum, ranging from those with relatively good-sized RV chambers to those with significant RV hypoplasia or RV-dependent coronary circulation (1). Some degree of tricuspid valve hypoplasia is the rule and generally follows RV hypoplasia. Nevertheless, many patients with PA/IVS can achieve a biventricular circulation, and often their first step toward this is a trip as a newborn to the catheterization lab for valve perforation and dilation.
Power-law behavior reveals phase transitions in landscape controls of fire regimes

In low-severity fire regimes of the American West and elsewhere, landscape memory of fire events is registered in fire-scarred trees, with temporal record lengths often exceeding 200 years^1-5^. Understanding the environmental controls on historical wildfires, and how they changed across spatial scales, is difficult because there are no surviving explicit records of either weather or vegetation (fuels). We show how power laws associated with fire-event time series arise in limited domains of parameters that represent critical transitions in the controls on landscape fire. We used stochastic simulations iteratively with Monte Carlo inference to replicate the spatio-temporal structure of historical fire-scar records in forested watersheds of varying topographic complexity. We find that the balance between endogenous and exogenous controls on fire spread shifts with topographic complexity, where in the most complex landscapes the endogenous controls dominate and the pattern exhibits criticality. Comparison to an self-organized criticality (SOC) model^6,7^ shows that the latter mimics historical fire only in a limited domain of criticality, and is not an adequate mechanism to explain landscape fire dynamics, which are shaped by both endogenous and exogenous controls. Our results identify a continuous phase transition in landscape controls, marked by power laws, and provide an ecological analogue to critical behavior in physical and chemical systems^8-11^. This explicitly cross-scale analysis provides a paradigm for identifying critical thresholds in landscape dynamics that may be crossed in a rapidly changing climate.
Through the Student's Eyes: On Pimping

A medical student's humorous poem about fact-retrieval on demand. Virtual Mentor is a monthly bioethics journal published by the American Medical Association.
Meteorological Radar Observations from Mobile Platforms

Over two decades ago Lhermitte (1967, 1972) discussed the possibilities of airborne radars for meteorological research, and Atlas (1963) discussed the early attempts at the Air Force Cambridge Geophysical Laboratories to construct an airborne weather radar. Due primarily to technological limitations, these plans were never implemented. The first implementation of a research-quality mobile weather radar occurred when, under the guidance of Byron Phillips and others, the NOAA P-3 aircraft were built in the early 1970s and included nose, belly and tail weather radars. The NOAA P-3 airborne radar reflectivity observations have played a strong role in developing our understanding of hurricanes (e. g., see Black et al., 1972; Marks, 1981; Barnes et al., 1983; Jorgensen, 1984a,b). The Doppler capability was initially tested in one of the tail radars and plans were made for eventual implementation of Doppler capabilities in both aircraft. The capabilities of these airborne Doppler radars were evaluated first using data collected in 1982 by Jorgensen et al. (1983a), and then more extensively by Hildebrand and Mueller (1985) and Mueller and Hildebrand (1985).
Youth's Perspective of Responsibility: Exploration of a Construct for Measurement with Youth with Developmental Disabilities.

Aims: There is a need to develop self-reports that measure youth’s responsibility for major life tasks. We examined if the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test’s (PED...
Skeletal muscle fibrosis is associated with decreased muscle inflammation and weakness in patients with chronic kidney disease.

Muscle dysfunction is an important cause of morbidity among patients with chronic kidney disease (CKD). Although muscle fibrosis is present in a CKD rodent model, its existence in humans and its im...
Vanadium-Catalyzed Coupling of Allenols with Electrophilic Halide Sources for the Formation of α-Halo-α',β'-unsaturated Ketones.

A vanadium-catalyzed coupling of allenylic alcohols with electrophilic halide sources to form α-halo-α′,β′-unsaturated ketones is described. The process proceeds through a metal enolate formed from the 1,3-transposition of an allenol that is initiated by a cheap and earth-abundant vanadium oxo catalyst. Fluorine, chlorine, and bromine electrophiles can be utilized, and the resulting products can give rise to the introduction of nitrogen, oxygen, sulfur, and iodine nucleophiles α to the ketone through substitution chemistry.
Metabolomics in the prevention and management of asthma.

Asthma is a complex syndrome that is influenced by both genetic and environmental factors. Determination of its pathobiology requires investigations on the outcome of transcriptional and translatio...
Weight tracking in childhood and adolescence and type 2 diabetes risk

The aim of this work was to examine the associations of average weight and weight velocity in three growth periods from birth through adolescence with type 2 diabetes incidence. Child participants were selected from a 43 year longitudinal study of American Indians to represent three growth periods: pre-adolescence (birth to ~8 years); early adolescence (~8 to ~13 years); and late adolescence (~13 to ~18 years). Age-, sex- and height-standardised weight z score mean and weight z score velocity (change/year) were computed for each period. Participants were followed for up to 25 years from the end of each growth period until they developed diabetes. Associations of weight z score mean or weight z score velocity with diabetes incidence were determined with sex-, birth date- and maternal diabetes-adjusted Poisson regression models. Among 2100 participants representing the pre-adolescence growth period, 1558 representing the early adolescence period and 1418 representing the late adolescence period, there were 290, 315 and 380 incident diabetes cases, respectively. During the first 10 years of follow-up, the diabetes incidence rate ratio (95% CI) was 1.72 (1.40, 2.11)/SD of log10 weight z score mean in pre-adolescence, 2.09 (1.68, 2.60)/SD of log10 weight z score mean in early adolescence and 1.85 (1.58, 2.17)/SD of log10 weight z score mean in late adolescence. The diabetes incidence rate ratio (95% CI) was 1.79 (1.49, 2.17)/SD of log10 weight z score velocity in pre-adolescence, 1.13 (0.91, 1.41)/SD of log10 weight z score velocity in early adolescence and 1.29 (1.09, 1.51)/SD of log10 weight z score velocity in late adolescence. There were strong correlations in the weight z score means and weak correlations in the weight z score velocities between successive periods. Higher weight and accelerated weight gain in all growth periods associate with increased type 2 diabetes risk. Importantly, higher weight and greater weight velocity during pre-adolescence jointly associate with the highest type 2 diabetes risk.
Harvest and Culture of Porcine Adipose-Derived Mesenchymal Stem Cells for Autologous Transplantation

Importance: Transplantation of adipose-derived (mesenchymal) stem cells (ADSCs) are currently under investigation for numerous novel regenerative cell therapies of the head, neck and periphery. Critical to the development of these techniques is the availability of large-animal models that can be used to test the safety and efficacy of these approaches in a manner that provides source material (in this case MSC) analogous to those developed in humans. Objective: To describe the surgical technique and laboratory procedures for harvesting and isolating porcine ADSCs that are functionally equivalent to human ADSCs without sacrificing the donor animal. Methods: The reagents and methods used in the porcine model described were purposefully focused to be able to be sufficiently analogous to those used in humans such that data developed using these techniques should support the use of porcine models for regulatory submissions. Results: We describe a method and confirm the activity of functionally analogous adipose derived porcine MSC. Two conditions were critical to move gain analogous performance: the cells needed to be incubated at porcine body temperature (39C) and the cells were more sensitive to initial plating densities with plating densities of 20,000 cells/cm2 being optimal.
Genome-wide capture sequencing to detect hepatitis C virus at the end of antiviral therapy

Viral relapse is a major concern in hepatitis C virus (HCV) antiviral therapy. Currently, there are no satisfactory methods to predict viral relapse, especially in the era of direct acting antivirals in which the virus often quickly becomes undetectable using PCR-based approaches that focus on a small viral region. Next-generation sequencing (NGS) provides an alternative option for viral detection in a genome-wide manner. However, owing to the overwhelming dominance of human genetic content in clinical specimens, direct detection of HCV by NGS has a low sensitivity and hence viral enrichment is required. Based on template-dependent multiple displacement amplification (tdMDA), an improved method for whole genome amplification (Wang et al., 2017. Biotechniques 63, 21–27), we evaluated two strategies to enhance the sensitivity of NGS-based HCV detection: duplex-specific nuclease (DSN)-mediated depletion of human sequences and HCV probe-based capture sequencing. In DSN-mediated depletion, human sequences were significantly reduced in the two HCV serum samples tested, 65.3% → 55.6% → 33.7% (#4727) and 68.6% → 56% → 21% (#4970), respectively for no normalization, self- and driver-applied normalization. However, this approach was associated with a loss of HCV sequences perhaps due to its micro-homology with the human genome. In capture sequencing, HCV-mapped sequencing reads occupied 96.8% (#4727) and 22.14% (#4970) in NGS data, equivalent to 1936x and 7380x enrichment, respectively. Capture sequencing was then applied to ten serum samples collected at the end of HCV antiviral therapy. Interestingly, the number of HCV-mapped reads was significantly higher in relapsed patients (n = 5) than those from patients with sustained virological response (SVR) (n = 5), 102.4 ± 72.3 vs. 2.6 ± 0.55, p = 0.014. Our data provides concept evidence for a highly sensitive HCV detection by capture sequencing. The abundance difference of HCV sequencing reads at the end of HCV antiviral therapy could be applied to predict treatment outcomes.
Adolescent drug use initiation and transition into other drugs: A retrospective longitudinal examination across race/ethnicity

Abstract Background Understanding adolescent drug use mechanisms is critical for drug use prevention. Although some theories such as the gateway theory suggest that drug users gradually transition into using more addictive drugs, there is no consensus about such a hypothesis. One important factor that hinders the advancement of knowledge in this area is the scarcity of longitudinal studies examining the type of drugs adolescents initially use and the different pathways adolescents take to transition into using other drugs as they grow older. Methods Using the pooled sample of adolescent dug users (14–17 years old; n = 10,644) from the National Survey on Drug Use and Health (2015–2018), we constructed longitudinal data on adolescents’ illicit drug use history other than the use of tobacco and alcohol based on the age of drug initiation. This allowed us to investigate what drugs were initially used by adolescents, how the use of these drugs may have progressed into a new drug, and whether there were racial/ethnic differences in the initiation and progression. The retrospective longitudinal data analyses applied life table method and Cox regression models. Results Two thirds of the adolescent drug users initiated their drug use trajectories with marijuana, one quarter with inhalants, and the remaining with hallucinogens, prescription drugs, and hard drugs. Adolescent drug users who initiated with different drugs showed unique trajectories to the use of a new drug. By year 8, the probability of using a new drug was about 40% and 70% to 80% for adolescents who initiated with inhalants and other drugs, respectively. The probability of using a new drug for adolescents who initiated with marijuana and inhalants accumulated stably over time, and its difference with that of other drug users diminished over time. The multivariate Cox regression models suggest the observed discrepancies generally held after controlling for covariates. There were also racial/ethnic differences in adolescent drug use initiation and progression, with Black/African American adolescents being the least likely to switch to the use of a new drug. Conclusion Adolescents’ initial use of marijuana and inhalants may lead to substantial risks of using other drugs over time. It is therefore important to screen adolescent drug use comprehensively and provide early interventions to prevent an escalation to more detrimental drugs. The findings provide new evidence to support aspects of both the gateway and generalized risk drug use theories.
The Original Anatomic Reconstruction of Palmar and Dorsal Radioulnar Ligaments for Distal Radioulnar Joint Instability

Thirty years ago, the first anatomic reconstruction of the palmar and dorsal radioulnar ligaments for chronic distal radioulnar joint (DRUJ) instability was proposed by Sanders. In this surgical technique, the midpoint of a free tendon autograft is firmly secured in a bony tunnel at the ulnar fovea. The 2 graft limbs anchored at the fovea traverse the DRUJ and are securely woven into the periarticular soft tissues radially, reproducing the ligamentous anatomy while not overconstraining the joint. This report documents the original anatomic DRUJ reconstruction technique described by Sanders and our procedure modifications.
Funding Liquidity and the Valuation of Mortgage-Backed Securities

We study the relationship between funding liquidity and the valuation of mortgage-backed securities. Most of the financing for mortgage-backed securities occurs through a trade known as a dollar roll, the simultaneous sale and purchase of forward contracts on mortgage-backed securities that is analogous to a repurchase agreement. We develop a four-factor no-arbitrage model for valuing mortgage-backed securities that allows for the valuation of dollar rolls. Unlike previous models of the dollar roll, we allow for the possibility of a prepayment risk premium. We develop a new model-implied measure of funding liquidity of MBS investors that is independent of prepayment risk premia and agency credit spreads. We find that our implied funding liquidity spread is strongly related to measures of intermediary balance sheet constraints and primary dealer positions in mortgage-backed securities.
A Dynamic Efficient Sensory Encoding Approach to Adaptive Tuning in Neural Models of Visual Motion Processing

This paper introduces a self-tuning mechanism for capturing rapid adaptation to changing visual stimuli by a population of neurons. Building upon the principles of efficient sensory encoding, we show how neural tuning curve parameters can be continually updated to optimally encode a time-varying distribution of recently detected stimulus values. We implemented this mechanism in a neural model that produces human-like estimates of self-motion direction (i.e., heading) based on optic flow. The parameters of speed-sensitive units were dynamically tuned in accordance with efficient sensory encoding such that the network remained sensitive as the distribution of optic flow speeds varied. In two simulation experiments, we found that model performance with dynamic tuning yielded more accurate, shorter latency heading estimates compared to the model with static tuning. We conclude that dynamic efficient sensory encoding offers a plausible approach for capturing adaptation to varying visual environments in biological visual systems and neural models alike.
Combining Lab Experiments and Industry Practice Data in Transaction Cost Analysis: The Case of Competition as a Safeguard

Extant empirical work in TCA relies almost exclusively on cross-sectional survey data on firm behavior to test predictions about vertical integration, long-run contracts, alliances and the like. Such designs shed useful light on the causal mechanisms supposedly responsible for the effects, but do not develop the details. Many of these designs also offer scarce insight into the profit implications inherent in the theory. Cognizant of these gaps, we combine a laboratory experiment and cross-sectional industry practice data to offer the first empirical evidence of "invited" competition as a safeguard for buyers' specific investments. Specifically, our lab data offers direct evidence of the suppression of opportunism. As per the theory, competition from a license holds down price hikes that exploit locked-in buyers in follow-on time periods. The lab data also show competing with a licensee is more attractive to the original monopolist as potential buyers need to make larger supplier-specific expenditures. The reverse is true when the focal product provides buyers with larger economic value. Interestingly, these effects show some systematic deviation from the sub-game perfect predictions of the game-theoretic models. Our industry data show that firms behave according to the prediction that products requiring greater levels of supplier-specific investments are more likely to be licensed. We close with a discussion of the economics of safeguards and the methodological implications of the studies.
"Menaced Rationality": Husserl and Merleau-Ponty on the Crisis and Promise of Science.

Abstract In this paper I provide an overview of Husserl's and Merleau-Ponty's phenomenological critique of science, and suggest that such a critique is not only necessary in order to resolve an aporia that is otherwise apparently endemic to science, but that such a critique may also offer resources for productively addressing related philosophical difficulties, particularly the relationship between ideality and materiality/“nature.” Following Husserl and Merleau-Ponty, I maintain that only a phenomenologically grounded science can be consistently “scientific.”
Overview of Animal Models of Asthma

Asthma is an inflammatory disease characterized by airways obstruction, airways hyperresponsiveness, excessive mucous secretion and cough. Guinea pig airways display many anatomical, physiological and pharmacological attributes of human airways, making this species ideal for modeling the asthmatic condition. This unit provides an overview of animal models of asthma, including definitions, descriptions of available animal models, and discussion of numerous critical issues to consider before designing a model to study this complex disease.
Performance Analysis of a Mixed Traffic Network in a Manufacturing Environment

The computer integrated automated factory is characterised by several intelligent devices distributed in the factory communicating with each other. The communication network used in the factory should be designed to satisfy disparate communication requirements. IEEE 802.4 token bus has been chosen as the standard by the Manufacturing Automation Protocol (MAP). In this paper we model and analyse a typical token bus network used in a factory environment. We model the network as a multiqueue system and derive the performance measures in terms of the network parameters.
β‐Chlorovinyl Isoamyl Ketone

β-Chlorovinyl isoamyl ketone product: β-chlorovinyl isoamyl ketone Keywords: addition, to CC; acetylene; acetylene, explosion hazard; β-chlorovinyl isoamyl ketone, irritant
Most asthmatics have gastroesophageal reflux with or without bronchodilator therapy.

Abstract The relationship between gastroesophageal reflux and asthma has not been clearly defined. We measured the lower esophageal sphincter pressures and studied gastroesophageal reflux patterns over 24 hours using an ambulatory Gastroreflux Recorder (Del Mar Avionics, Irvine, CA) in 44 controls and 104 consecutive adult asthmatics. The presence or absence of reflux symptoms was not used as a selection criterion for asthmatics. All asthmatics had discrete episodes of diffuse wheezing and documented reversible airway obstruction of at least 20%. Patients underwent reflux testing while receiving, if any, their usual asthmatic medications: 71.2% required chronic bronchodilators and 28.8% required no bronchodilators. Compared with controls, asthmatics had significantly decreased lower esophageal sphincter pressures, greater esophageal acid exposure times, more frequent reflux episodes, and longer clearance times in both the upright and supine positions ( P
Effective Mucosal Immunity to Anthrax: Neutralizing Antibodies and Th Cell Responses Following Nasal Immunization with Protective Antigen

Mucosal, but not parenteral, immunization induces immune responses in both systemic and secretory immune compartments. Thus, despite the reports that Abs to the protective Ag of anthrax (PA) have both anti-toxin and anti-spore activities, a vaccine administered parenterally, such as the aluminum-adsorbed anthrax vaccine, will most likely not induce the needed mucosal immunity to efficiently protect the initial site of infection with inhaled anthrax spores. We therefore took a nasal anthrax vaccine approach to attempt to induce protective immunity both at mucosal surfaces and in the peripheral immune compartment. Mice nasally immunized with recombinant PA (rPA) and cholera toxin (CT) as mucosal adjuvant developed high plasma PA-specific IgG Ab responses. Plasma IgA Abs as well as secretory IgA anti-PA Abs in saliva, nasal washes, and fecal extracts were also induced when a higher dose of rPA was used. The anti-PA IgG subclass responses to nasal rPA plus CT consisted of IgG1 and IgG2b Abs. A more balanced profile of IgG subclasses with IgG1, IgG2a, and IgG2b Abs was seen when rPA was given with a CpG oligodeoxynucleotide as adjuvant, suggesting a role for the adjuvants in the nasal rPA-induced immunity. The PA-specific CD4(+) T cells from mice nasally immunized with rPA and CT as adjuvant secreted low levels of CD4(+) Th1-type cytokines in vitro, but exhibited elevated IL-4, IL-5, IL-6, and IL-10 responses. The functional significance of the anti-PA Ab responses was established in an in vitro macrophage toxicity assay in which both plasma and mucosal secretions neutralized the lethal effects of Bacillus anthracis toxin.
“RETRO-,” AN EMERGING PREFIX FOR FUTURE TECHNOLOGICAL DEVELOPMENT?

It is proposed that the prefix “retro” can serve as an irreverent, but timely buzzword for the development of new technology to meet human needs. Society has carried out experiments at a very large scale for the last century or so to meet our collective needs though the use of fossil-based fuels and synthetic materials. Those experiments have seemed successful in the short term, feeding more of us and supplying a lot of us with rising standards of living. But the experiments often have failed us in terms of sustainability. A health crisis, global warming, and resource depletion are urgent problems caused by careless use of fossil fuels and related synthetic organic chemicals. The prefix “retro,” as in “retrotechology,” signals a disciplined return to a reliance on nature-based products, as well as a respect for the beauty, but also the fragile character of our natural environment.
High-order PMD emulator

A system for generating polarization mode dispersion has been developed to reproduce in the laboratory, a close approximation to the polarization mode dispersion (PMD) of fiber links. A multi-stage system of rotating wave plates and combinations of birefringent elements generates a mixture of first order, second order and higher order PMD suitable for testing OC-192 and OC-768 hardware. The PMD Emulator can be operated in either static or time-varying modes. In the static mode first order PMD is generated with the Differential Group Delay continuously adjustable from 0 to 160 ps. In the dynamic mode time-varying PMD containing first and higher orders is generated with an approximately Maxwellian DGD distribution. The PMD emulator generates PMD variations at adjustable frequencies up to 400 Hz.
On the wave transmission across the interface of two elastic half spaces with nonlocal cohesion forces

Wave propagation across the interface of two elastic half-infinite media is examined assuming long-range action of cohesive forces. The nonlocal elastic moduli are first established by solving an auxiliary problem involving longitudinal waves in an infinite space. With constitutive equations determined, the conditions of continuity of displacements and of balance of forces at the interface of the media lead to the relations between the amplitudes of the incident, reflected and transmitted wave. The relations are illustrated by graphs.
RSUV isomorphisms for TAC i , TNC i and TLS

We investigate the second order bounded arithmetical systems which is isomorphic to TACi, TNCi or TLS.
Excitation of the six lowest electronic transitions in water by 9?20?eV electrons

We report differential and integral cross sections for excitation of the ^(3)B_1, ^(1)B_1, ^(3)A_2, ^(1)A_2, ^(3)A_1 and ^(1)A_1 states of H_(2)O by 9–20 eV electrons. The measurements are taken by conventional differential electron energy loss spectroscopy techniques, while the calculations employ the Schwinger multichannel method within a ten-channel approximation. The new data are compared with previous experimental and theoretical results. The present measurements and calculations agree reasonably well both with each other and with prior theoretical efforts but show discrepancies with prior measurements. Reasons for those discrepancies are considered and discussed.
Quantitative measurement of grain boundary potentials on the nanoscale by off-axis electron holography

We explore the quantification of the grain boundary potential across c-axis aligned twist boundaries in ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$ superconductors using off-axis electron holography. In separating the bulk contribution to the potential profile we find that a kinematical treatment is sufficient to quantify the potential associated with only the grain boundary. We model the measured potential with a Gaussian function to determine the charge density across several boundaries as a function of the interface misorientation. We further examine the effect of objective lens aberration and defocus on the potential quantification for subnanometer resolution and conclude that it may be neglected for spatial resolution above 5 \AA{}, which is suitable for the boundaries under study. We find no dependence of the measured potential or grain boundary width on the misorientation angle. We measure an average grain boundary potential of $2.18\ifmmode\pm\else\textpm\fi{}0.12\mathrm{V}$ corresponding to about a 8.6 \AA{} interface width, and conclude that a negative charge of ${1.7e}^{\ensuremath{-}}/\mathrm{unit}$ cell is associated with the grain boundary core. The treatment presented here has general validity for the quantitative study of interface potential.
No difference in meeting hemoglobin and albumin targets for dialyzed children with urologic disorders.

Urologic disorders are the most common cause of chronic kidney disease in children. To determine whether children with urologic etiology of end-stage renal disease (ESRD) fare better than children with ESRD from other causes while on dialysis, we conducted a cross-sectional study of children <18 years receiving peritoneal and hemodialysis in the United States using data from the Centers for Medicare & Medicaid Services 2005 ESRD CPM Project. We compared baseline demographics and the study groups. In multivariate logistic regression analysis of 1,286 subjects, we assessed whether children with urologic disorders had a higher odds of meeting adult KDOQI targets for hemoglobin levels ≥11 g/dl and albumin ≥3.5 BCG/3.2 BCP g/dl. We conducted a subset analysis of 1,136 patients to examine the impact of erythropoietin on hemoglobin targets. Our results did not reveal differences in achievement of adult hemoglobin targets (adjusted OR: 1.27; p value 0.09; CI: 0.97–1.66) or in the subset analysis with erythropoietin (adjusted OR: 1.32; p value 0.06; CI: 0.98–1.78) or albumin targets (adjusted OR: 1.22; p value 0.21; CI: 0.90–1.65) in adjusted analyses. Due to our study’s limitations, it is difficult to determine whether this may result from treatment prior to dialysis initiation or treatment effect of dialysis rather than underlying diagnosis.
Phosphatidylinositol-4,5-bisphosphate ionization and domain formation in the presence of lipids with hydrogen bond donor capabilities

Abstract Phosphatidylinositol-4,5-bisphosphate (PI(4,5)P 2 ) is an important lipidic signaling molecule that is involved in a broad range of cellular processes. Its interaction with proteins and its lateral distribution are governed by the ionization state of the phosphomonoester groups and its ability to form intra- and intermolecular hydrogen bonds. In this study we have investigated the ionization state of PI(4,5)P 2 in ternary lipid vesicle systems that contain in addition to PI(4,5)P 2 and phosphatidylcholine (PC) either phosphatidylethanolamine (PE), phosphatidylserine (PS) or phosphatidylinositol (PI). In the presence of PE we find an increased ionization of PI(4,5)P 2 , which can be attributed to increased deprotonation due to hydrogen bond formation between PE and the PI(4,5)P 2 phosphomonoester groups. However, the effect of PE on PI(4,5)P 2 ionization is significantly smaller than it had been found previously for phosphatidic acid in the presence of PE ( Kooijman et al., 2005 ). The reduced impact of PE on PI(4,5)P 2 ionization can be attributed to competing intramolecular hydrogen bond formation between the phosphomonoester groups and neighboring hydroxyl groups. It is noteworthy that the presence of PE affects more strongly the ionization of the 5-phosphate group than that of the 4-phosphate, suggesting that the interaction of PE with the 5-phosphate is stronger. In PI(4,5)P 2 /PS/PC lipid vesicles, the presence of PS was expected to yield an increased protonation of the PI(4,5)P 2 phosphomonoester groups due to a decreased interfacial pH as a result of the increased negative interfacial charge. However, the effect of PS on PI(4,5)P 2 ionization is only minor, potentially suggesting that PS and PI(4,5)P 2 are demixed. The PI(4,5)P 2 /PI/PC vesicle system was characterized by a surprising mixing behavior that has potentially far reaching consequences: fluorescence microscopy measurements of giant unilammellar vesicles composed of PI(4,5)P 2 /PI/PC at physiological concentrations show that PI and PI(4,5)P 2 form macroscopic, fluid phase domains in contact with a fluid PC rich phase (fluid/fluid demixing). Despite the fact that PI and PI(4,5)P 2 co-localize, the effect of PI on PI(4,5)P 2 ionization behavior is only noticeable above pH 7. Apparently two opposing effects lead to the observed behavior: Due to the presence of the anionic PI, the interfacial pH drops, which is expected to lead to an enhanced protonation of the PI(4,5)P 2 phosphomonoester groups. In turn, hydrogen bond formation between PI and PI(4,5)P 2 would lead to the opposite, i.e. increased deprotonation of the phosphomonoester group. Apparently these two effects compensate each other for pH values smaller than about 7, while for higher pH values the increased interfacial pH in the presence of PI has a stronger impact than PI/PI(4,5)P 2 hydrogen bond formation. The cooperative formation of PI/PI(4,5)P 2 mixed domains has potentially important ramifications for the spatial organization of phosphoinositide mediated signaling events.
Liquid Crystalline Aromatic Polyesters

Abstract The background to development of liquid crystalline aromatic polyesters is reviewed. Specific programs directed at the development of the homopolymer of p-hydroxybenzoic acid and copolymer with biphenol terephthalate are described. Work on novel processing techniques is highlighted in this paper while questions of synthesis, structure, and properties are considered somewhat more briefly.
MATHEMATICAL MODELING OF FISCHER- TROPSCH SLURRY BUBBLE COLUMN REACTORS

Three-phase slurry bubble column reactors are used in a wide variety of biological and chemical operations. This work is a comprehensive review of the mathematical modeling of such reactors for the Fischer-Tropsch (F-T)synthesis as applied to indirect coal liquefaction. The salient features of the F-T slurry bubble column reactors are described, and the fundamental mass transfer and kinetic rate processes that are needed to model the reactor performance are discussed. A brief description of the F-T chemistry, including principal F-T reactions, properties of commonly used F-T catalysts, and the Schulz-Flory distribution, is also given. All of the mathematical models for the F-T slurry process that have been developed to date are presented in enough detail to highlight the basic relations as well as the implicit assumptions. The refinements introduced by different workers are emphasized, as well as the numerical results obtained from these models either in the perspective of comparison with experimental dat...
Difficulties with the use of penalized likelihood criteria in antedependence and polynomial models

Penalized likelihoods are commonly used as model selection criteria. They involve maximizing a penalized likelihood IC(k), over a set of competing models (indexed by k). The study of their performance has been limited to asymptotic results. In normal regression models it is often possible to study finite sample properties of these criteria by formulating the likelihood in terms of residual sums of squares. Some models, like polynomial regression and antedependence models, show a natural sequence of nested alternatives. We discuss the small sample behavior of IC(k) and E(IC(k)) as functions of k for these models and present some problems that can occur with small sample sizes.
A surgical technique for resecting malignancies invading the facial nerve and petrous pyramid.

Certain head and neck malignancies tend to invade branches of the cranial nerves and progress centripetally. The maxillary and mandibular divisions of the V (trigeminal) nerve are the most commonly invaded, but the VII (facial) nerve may harbor extensions of primary parotid malignancies and/or skin cancers originating in or near the ear. Paresis of the VII nerve signifies a serious but not entirely hopeless situation if countered with an appropriate surgical procedure. The optimal treatment of malignancies invading cranial nerves is surgical excision, which may necessitate removal of substantial portions of the cranium. Surgical pursuit of a malignancy in the facial nerve leads to a direct confrontation with the petrous pyramid of the temporal bone. Resection of the petrous pyramid is surgically feasible, but, if performed en bloc, exacts a high morbidity and mortality. An alternate technique in which the soft tissue and bones are removed disjunct is advocated. In this technique, the soft tissues are excised flush with the surface of the temporal bone. After making perforator and burr openings in the squamous temporal bone, a subtotal temporal craniectomy is completed with rongeurs. A prerequisite for success with this technique is the rotation of a large scalp flap and other local flaps to cover the exposed meninges and carotid arteries. A resume of four cases using this technique is presented. The age of the patients, the type, stage, and duration of the malignancies, and other factors which might influence the end stage results are given.
The utility of circulating markers to predict bone loss across the CKD spectrum.

Patients with CKD are at increased risk of bone loss and fractures. Prospective observational studies have shown that the severity of kidney disease is directly associated with the amount of bone loss ([1][1]–[4][2]). In CKD, fractures are 2- to 14-fold more common than in the general population
Case profile: Wilms tumor masquerading as extrarenal mass

Abstract Urograms of interest to our readers are welcome from urologists and radiologists. Contributions, including an abbreviated history and legend for the films, are to be sent to Arthur N. Tessler, M.D., feature editor.
NONTRAUMATIC PARIETAL SUBCORTICAL HEMORRHAGE: CLINICAL-COMPUTED TOMOGRAPHIC CORRELATIONS

Abstract The clinical and computed tomographic findings in 25 patients with parietal lobe hematomas are discussed. Six patients had anterior-lateral parietal hematomas (18 to 36 mm). These patients were normotensive. No etiology was delineated even when angiography was utilized. Six patients had medial parietal hematomas (12 to 24 mm) with extension to the thalamus. Two patients were normotensive and six were hypertensive. Three patients had posterior parietal hematomas (10 to 18 mm). These patients were hypertensive. Eight patients had parietal hematomas extending to the temporal and frontal region (30 to 60 mm). Three of these patients died. Four patients were normotensive and four were hypertensive. One of these normotensive patients had cerebral metastases. Two patients had parietal hematomas which extended to the occipital region (20 to 34 mm). These patients were normotensive. Peripheral rim enhancement was demonstrated on follow-up CT scan (performed 2 to 4 weeks after the initial study) in 14 of 21 cases. On follow-up CT of the 21 surviving patients with parietal hematomas (excluding the case due to metastases) performed more than 4 weeks after the clinical ictus, 14 appeared hypodense and 7 appeared isodense. Residual neurological deficit and recurrent seizures were more frequent if the hematoma “aged” to a hypodense appearance.
Foraging ability of rufous hummingbirds on hummingbird flowers and hawkmoth flowers.

Abstract We examine the suitability of ornithophilous flowers and sphingophilous flowers in Ipompsis and Aquilegia for nectar foraging by the hummingbird Selasphorus rufus. In S. rufus, bill length averages 18.9 mm in females and 17.3 mm in males. Maximal tongue extension approximates bill length, suggesting that birds can feed from floral tubes up to 33.5 mm in length. However, their ability to do so is limited by two factors. First, the maximal depth at which S. rufus can extract nectar decreases with the width of the floral tube. Second, feeding time is shortest in short floral tubes and progressively increases as the tubes lengthen because of increased time required for tongue extension and retraction. Hence, nectar foraging occurs with optimal efficiency in moderately broad floral tubes with lengths that do not exceed or only slightly exceed the bill length plus </=5-mm tongue extension. In most ornithophilous taxa of Ipomopsis and Aquilegia, the floral tubes have lengths and widths in the optimal range for nectar foraging by S. rufus, whereas in the sphingophilous taxa, the basal nectar either may be reached but at much higher cost or, more frequently, is beyond reach of bills and tongues. The flower-visiting habits of S. rufus and other hummingbirds in nature are generally congruent with these conclusions and support the case for coadaptation between these plants and pollinators.
Laser gas-discharge absorption measurements of the ratio of two transition rates in neutral argon

The ratio of line strengths for the two argon transitions, 3p{sup 5}({sup 2}P{sub 1/2}{sup o})4s[1/2]{sub 1}{sup o}{yields}3p{sup 5}({sup 2}P{sub 3/2}{sup o})4p[3/2]{sub 2} at wavelength 922.7 nm and 3p{sup 5}({sup 2}P{sub 1/2}{sup o})4s[1/2]{sub 1}{sup o}{yields}3p{sup 5}({sup 2}P{sub 3/2}{sup o})4p[5/2]{sub 2} at wavelength 978.7 nm, is measured in an argon pulsed discharge with the use of a single-mode Ti:sapphire laser. The result 3.29(0.13) is in agreement with our theoretical prediction 3.23 and with a less accurate ratio 2.89(0.43) from the NIST database.
Development of normal mice by in vitro fertilization.

In vitro fertilization of mammalian ova has been successfully carried out in the rabbit1–3 and the hamster4,5, but development of fertilized ova beyond the two-cell stage has not been achieved6. Brinster et al.7 have observed fertilization and blastocyst development in explanted Fallopian tubes using organ culture. More recently, Whittingham8 has successfully fertilized mouse eggs in vitro, transplantation of which into pseudo-pregnant recipient mothers yielded 17 day old foetuses. The present studies confirm the results of Whittingham8 and further demonstrate that apparently normal full-term progeny can be obtained from implantation of in vitro fertilized eggs that have been maintained in culture to the blastocyst stage.
A modified wall wake velocity profile for turbulent compressible boundary layers.

The law of the wake and the law of the wall in incompressible turbulent boundary layers formulated by Coles (1956) and their use by Mathews et al. (1970) in the development of a wall-wake representation of the velocity profile in a form applicable for isoenergetic compressible boundary layers are extended to a modified wall-wake velocity profile for turbulent compressible boundary layers. The modified wall-wake profile is shown to provide good representations of experimental velocity distributions.
Let it rain: Weather effects on activity stress and scheduling behavior

Travel and activity scheduling decisions largely depend on travelers’ responses to prevailing trip conditions. These could be impacted by environmental situations, such as adverse weather, which can increase the variability in travel times, practical capacity and other system properties. Understanding and modeling the relationship between travel and activity decisions and adverse weather is important for devising and evaluating transportation management strategies that rely on adjustments and shifts in behavior. This study focuses on the impact of rainfall precipitation on activity decisions, more specifically the perceived stress underlying these decisions. In the current study, activity scheduling decisions for discretionary activities are examined under different rainfall levels, but given consistent data on other forms of precipitations, such as snow sleet or hail, this study could be extended to these cases. Activity stress is modeled under a discrete choice framework. The results show that the perceived activity stress differs under rainfall to some extent, depending on the number of activities in a traveler’s activity queue, and the number of activities completed. The study also reveals that travel behavior may differ under rainfall, suggesting that travelers’ may perceive information and uncertainty differently, relative to conditions with less variability in weather. Furthermore, issues concerning climatology data requirements for transportation models are discussed.
New shielding configurations for a simultaneous PET/MRI scanner at 7T.

Understanding sources of electromagnetic interference are important in designing any electronic system. This is especially true when combining positron emission tomography (PET) and magnetic resonance imaging (MRI) in a multimodality system as coupling between the subsystems can degrade the performance of either modality. For this reason, eliminating radio frequency (RF) interference and gradient-induced eddy currents have been major challenges in building simultaneous hybrid PET/MRI systems. MRI requires negligible RF interference at the Larmor resonance frequency, while RF interference at almost any frequency may corrupt PET data. Moreover, any scheme that minimizes these interactions would, ideally, not compromise the performance of either subsystem. This paper lays out a plan to resolve these problems. A carbon fiber composite material is found to be a good RF shield at the Larmor frequency (300 MHz in this work) while introducing negligible gradient eddy currents. This carbon fiber composite also provides excellent structural support for the PET detector components. Low frequency electromagnetic radiation (81 kHz here) from the switching power supplies of the gradient amplifiers was also found to interfere with the PET detector. Placing the PET detector module between two carbon fiber tubes and grounding the inner carbon fiber tube to the PET detector module ground reduced this interference. Further reductions were achieved by adding thin copper (Cu) foil on the outer carbon fiber case and electrically grounding the PET detector module so that all 3 components had a common ground, i.e. with the PET detector in an electrostatic cage. Finally, gradient switching typical in MRI sequences can result in count losses in the particular PET detector design studied. Moreover, the magnitude of this effect depends on the location of the detector within the magnet bore and which MRI gradient is being switched. These findings have a bearing on future designs of PET/MRI systems.