cssi/SciSciGPT-SciSciNet huggingface dataset:
IRF4 Has a Unique Role in Early B Cell Development and Acts Prior to CD21 Expression to Control Marginal Zone B Cell Numbers

Strict control of B lymphocyte development is required for the ability to mount humoral immune responses to diverse foreign antigens while remaining self-tolerant. In the bone marrow, B lineage cells transit through several developmental stages in which they assemble a functional B cell receptor in a stepwise manner. The immunoglobulin heavy chain gene is rearranged at the pro B stage. At the large pre B stage, cells with a functional heavy chain expand in response to signals from IL-7 and the pre-BCR. Cells then cease proliferation at the small pre B stage and rearrange the immunoglobulin light chain gene. The fully formed BCR is subsequently expressed on the surface of immature B cells and autoreactive cells are culled by central tolerance mechanisms. Once in the periphery, transitional B cells develop into mature B cell subsets such as marginal zone and follicular B cells. These developmental processes are controlled by transcription factor networks, central to which are IRF4 and IRF8. These were thought to act redundantly during B cell development in the bone marrow, with their functions diverging in the periphery where IRF4 limits the number of marginal zone B cells and is required for germinal center responses and plasma cell differentiation. Because of IRF4’s unique role in mature B cells, we hypothesized that it may also have functions earlier in B cell development that cannot be compensated for by IRF8. Indeed, we find that IRF4 has a unique role in upregulating the pre-B cell marker CD25, limiting IL-7 responsiveness, and promoting migration to CXCR4 such that IRF4-deficient mice have a partial block at the pre-B cell stage. We also find that IRF4 acts in early transitional B cells to restrict marginal zone B cell development, as deletion of IRF4 in mature B cells with CD21-cre impairs plasma cell differentiation but has no effect on marginal zone B cell numbers. These studies highlight IRF4 as the dominant IRF family member in early B lymphopoiesis.
Homeostasis and biological rhythms in the rat during spaceflight.

The effects of microgravity on the physiological regulation of homeostatic systems is studied. The temperature and heart rate of rats exposed to seven days of microgravity and a 12:12 light/dark cycle are analyzed. A 24-hour nocturnal rhythmicity is observed in the control and in-flight heart rates and body temperatures. The preflight daytime body temperature was calculated as 37.2 + or - 0.03 C and in-flight as 37.4 + or 0.04 C; nighttime body temperature preflight daytime was determined as 38.0 + or - 0.02 C, and in-flight as 37.8 + or 0.06 C. The 24-hour mean heart rate was depressed from 412 + or - 3.3 bpm preflight to 373 + or - 2.4 bpm in-flight; this change is noted in both dark and light conditions. It is detected that microgravity alters the steady state regulation of heart rate and body temperature.
Stage of cirrhosis predicts the risk of liver-related death in patients with low Model for End-Stage Liver Disease scores and cirrhosis awaiting liver transplantation.

MELD has reduced predictive ability in cirrhotic patients with MELD ≤ 20. We aimed to assess whether a 5-stage clinical model identifies liver transplant (LT) candidates with low MELD who are at increased risk for death. We conducted a case-control study of cirrhotic subjects with MELD ≤ 20 awaiting LT at a single academic medical center from 2/2002-5/2011. Conditional logistic regression was used to evaluate the risk of liver-related death based on cirrhosis stage. We identified 41 case subjects who died from liver-related causes with a MELD ≤ 20 within 90 days of death while waiting for LT. Cases were matched with up to 3 controls, totaling 66 controls, based on listing year, age, gender, liver disease etiology, hepatocellular carcinoma, and MELD. Cirrhosis stage (1=no varices or ascites, 2=varices, 3=variceal bleed, 4=ascites, 5=ascites and variceal bleed) was assessed for all subjects. MELD scores were similar for cases and controls. Clinical states contributing to death in cases were: sepsis 48%, spontaneous bacterial peritonitis 42%, variceal bleeding 24%, and hepatorenal syndrome 21%. In univariate analyses, variceal bleed (OR 5.6, p= 0.003), albumin (OR 0.5, p=0.041), increasing cirrhosis stage (p=0.003) and reaching stage 2, 3, or 4 cirrhosis versus lower stages (OR 3.6, p=0.048; OR 7.4, p<0.001; OR 4.1, p=0.008; respectively), sodium < 135 (OR 3.4, p=0.006), and hepatic encephalopathy (OR 2.3, p=0.082) were associated with liver-related death. In a multivariable model including cirrhosis stage, albumin, sodium, and hepatic encephalopathy, increasing cirrhosis stage (p=0.010) was independently associated with liver-related death. In conclusion, assessing the cirrhosis stage in low MELD patients awaiting LT may help select candidates for more aggressive monitoring or for living donor or extended criteria donation.
Erratum to: Fluid-Like Swarms with Predictable Macroscopic Behavior

This paper is concerned with assuring the safety of a swarm of agents (simulated robots). Such behavioral assurance is provided with the physics method called kinetic theory. Kinetic theory formulas are used to predict the macroscopic behavior of a simulated swarm of individually controlled agents. Kinetic theory is also the method for controlling the agents. In particular, the agents behave like particles in a moving gas. The coverage task addressed here involves a dynamic search through a bounded region, while avoiding multiple large obstacles, such as buildings. In the case of limited sensors and communication, maintaining spatial coverage --- especially after passing the obstacles --- is a challenging problem. Our kinetic theory solution simulates a gas-like swarm motion, which provides excellent coverage. Finally, experimental results are presented that determine how well the macroscopic-level theory, mentioned above, predicts simulated swarm behavior on this task.
Auditory symmetry analysis.

The study of biological symmetry continues to be an important and active area of research, yet in the hearing sciences there are no established quantitative methods for measuring auditory asymmetries and dissimilarities in threshold tuning curves (i.e. audiograms). Using a paired design and adopting methods from the analysis of fluctuating asymmetry, we describe methods for auditory researchers interested in delineating auditory asymmetries and comparing tuning curves, behavioral or neural. We illustrate the methods using audiograms of the prothoracic T-cell interneuron in a nocturnal katydid (Neoconocephalus ensiger). The results show that 87–92 % of T-cells had right-minus-left threshold asymmetries no larger than expected from measurement error alone. Thus, apart from small random fluctuating asymmetries, T-cell pairs in N. ensiger showed no sensory bias and were bilaterally symmetrical from 5 to 100 kHz. The sensitivity of the methods for detecting tuning curve dissimilarities was confirmed in a sound lateralization paradigm by comparing the ‘symmetry’ (i.e. similarity) of T-cell tuning curves measured at 0 degrees stimulation with tuning curves measured at 90 degrees stimulation for the same T-cell. The results show that T-cell thresholds measured frontally (0 degrees) were significantly higher than those measured laterally (90 degrees), particularly for ultrasonic frequencies. Statistically, the directional shift (increase) in auditory thresholds was detected as a directional asymmetry in T-cell tuning, whose origin and functional significance to an insect behaving normally are discussed. The paper discusses practical considerations for detecting auditory asymmetries and tuning curve dissimilarities in general, and closes by questioning the relevance of auditory symmetry for sound localization in both vertebrates and insects.
Management of Head Trauma

Traumatic brain injury (TBI) is a major cause of disability and death in most Western nations and consumes an estimated $100 billion annually in the United States alone. In the last 2 decades, the management of TBI has evolved dramatically, as a result of a more thorough understanding of the physiologic events leading to secondary neuronal injury as well as advances in the care of critically ill patients. However, it is likely that many patients with TBI are not treated according to current treatment principles. This article presents an overview of the current management of patients with TBI.
Crack growth on the basal plane in single crystal zinc: experiments and computations

Crack propagation on the basal planes in zinc was examined by means of in situ fracture testing of pre-cracked single crystals, with specific attention paid to the fracture mechanism. During quasistatic loading, crack propagation occurred in short bursts of dynamic crack extension followed by periods of arrests, the latter accompanied by plastic deformation and blunting of the crack-tip. In situ observations confirmed nucleation and propagation of microcracks on parallel basal planes and plastic deformation and failure of the linking ligaments. Pre-existing twins in the crack path serve as potent crack arrestors. The crystallographic orientation of the crack growth direction on the basal plane was found to influence both the fracture load as well as the deformation at the crack-tip, producing fracture surfaces of noticeably different appearances. Finite element analysis incorporating crystal plasticity was used to identify dominant slip systems and the stress distribution around the crack-tip in plane str...
L1-mediated axon outgrowth occurs via a homophilic binding mechanism

The molecular mechanism by which the L1 cell adhesion molecule mediates neurite outgrowth has been examined. Purified L1 from mouse and L1 from chick brain were attached to nitrocellulose dishes. Both chick and mouse neurons were able to adhere to purified mouse L1 and chick L1. Both molecules promoted neurite extension from chick and mouse neurons. Addition of Fabs specific for chick L1 to the cultures inhibited chick neurite outgrowth on both mouse L1 and chick L1. These findings suggest that L1-like molecules support neurite outgrowth via a "homophilic" binding mechanism.
Fluoroscopic gating without implanted fiducial markers for lung cancer radiotherapy based on support vector machines

Various problems with the current state-of-the-art techniques for gated radiotherapy have prevented this new treatment modality from being widely implemented in clinical routine. These problems are caused mainly by applying various external respiratory surrogates. There might be large uncertainties in deriving the tumor position from external respiratory surrogates. While tracking implanted fiducial markers has sufficient accuracy, this procedure may not be widely accepted due to the risk of pneumothorax. Previously, we have developed a technique to generate gating signals from fluoroscopic images without implanted fiducial markers using template matching methods (Berbeco et al 2005 Phys. Med. Biol. 50 4481-90, Cui et al 2007b Phys. Med. Biol. 52 741-55). In this note, our main contribution is to provide a totally different new view of the gating problem by recasting it as a classification problem. Then, we solve this classification problem by a well-studied powerful classification method called a support vector machine (SVM). Note that the goal of an automated gating tool is to decide when to turn the beam ON or OFF. We treat ON and OFF as the two classes in our classification problem. We create our labeled training data during the patient setup session by utilizing the reference gating signal, manually determined by a radiation oncologist. We then pre-process these labeled training images and build our SVM prediction model. During treatment delivery, fluoroscopic images are continuously acquired, pre-processed and sent as an input to the SVM. Finally, our SVM model will output the predicted labels as gating signals. We test the proposed technique on five sequences of fluoroscopic images from five lung cancer patients against the reference gating signal as ground truth. We compare the performance of the SVM to our previous template matching method (Cui et al 2007b Phys. Med. Biol. 52 741-55). We find that the SVM is slightly more accurate on average (1-3%) than the template matching method, when delivering the target dose. And the average duty cycle is 4-6% longer. Given the very limited patient dataset, we cannot conclude that the SVM is more accurate and efficient than the template matching method. However, our preliminary results show that the SVM is a potentially precise and efficient algorithm for generating gating signals for radiotherapy. This work demonstrates that the gating problem can be considered as a classification problem and solved accordingly.
Fluoride Varnish Applications May Reduce the Formation of White Spot Lesions (WSL) Adjacent to Orthodontic Fixed Appliances

Article Title and Bibliographic Information Caries-preventive effectiveness of a fluoride varnish: a randomized controlled trial in adolescents with fixed orthodontic appliances. Stecksen-Blicks C, Renfors G, Oscarson ND, Bergstrand F, Twetman S. Caries Res 2007;41(6):455-9. Level of Evidence Level 2: Limited-quality, patient-oriented evidence. Strength of Recommendation Grade Not applicable. Purpose/Question The authors aimed at evaluating the efficacy of multiple topical fluoride (F) varnish applications at preventing WSL formation in adolescents, during treatment with fixed orthodontic appliances. Source of Funding Government and industry-With grants from the County Council of Vasterbotten (the a should have two dots above it), Sweden and the Swedish Dental Society; and with materials from Ivoclar Vivadent and 3M-Unitek. Type of Study/Design Randomized controlled trial.
Multifunctional chemical vapor sensors of aligned carbon nanotube and polymer composites.

Partially coating perpendicularly aligned carbon nanotube arrays with an appropriate polymer thin film along their tube length provides a novel concept for developing new sensors of high sensitivity, good selectivity, and excellent environmental stability for the detection of a broad class of chemical vapors with low power consumption. The absorption and desorption of chemical vapors by the polymer matrix cause changes in the inter-tube distance and, hence, the surface resistance across the nanotube film. Simple measurements of the resistance change, therefore, constitute the nanotube−polymer chemical vapor sensors. These rationally designed, aligned carbon nanotube−polymer composite films are flexible and can be effectively integrated into many systems for a wide range of potential applications, including their use as multifunctional sensors for sensing chemical vapors, mechanical deformations, thermal and optical exposures.
DNA synthesis without mitosis in amputated denervated forelimbs of larval axolotls.

Both forelimbs of axolotl larvae were amputated at the elbow and left limbs were immediately denervated. Both the left and right limbs of 4 larvae/day were examined for DNA synthesis (H3-thymidine-autoradiography) and mitotic index on days 1 to 7 post-amputation. DNA synthesis was evident in both innervated regenerating, and denervated non-regenerating limb stumps, on days 4, 5, 6, and 7. Mitotic index increased only in innervated limbs, beginning on day 5.
Mitigating the Variability of Wind and Solar Energy Through Pumped Hydroelectric Storage

Renewable power production is both variable and difficult to forecast accurately. These facts can make its integration into an electric grid problematic. If an area’s demand for electricity can be met without using renewable generation, the addition of renewable generation would not warrant a further increase in generation capacity. However, to effectively integrate large amounts of additional renewable generation, it is likely that a more flexible generation fleet will be required. One way of increasing a generation fleet’s flexibility is through the adoption of pumped hydroelectric storage (PHS, see the glossary for definitions of select terms). Like traditional hydropower generation, PHS is capable of quickly varying its power output but it is also capable of operating in reverse to store excess energy for later use. This paper will address many of the operational aspects of combining pumped hydroelectric storage (PHS), which is currently used to store excess energy from traditional generators, with wind and solar power generation.PJM, a grid operator in the Middle Atlantic States, defines capacity value for renewable generation as the percent of installed generating capacity that the generator can reliably contribute during summer peak hours. Existing wind generators inside PJM have an average capacity value of 13% and existing solar generators have a capacity value of 38%. The chief reason for these capacity values is that the renewable power production does not usually coincide with the hours of peak electricity demand during the summer. If PHS were used to firm renewable power generation, it would translate into increased utilization of the renewable generation that would displace the least efficient/most costly generators.A computer model with one minute granularity is constructed in order to study the operational requirements of PHS facilities. PJM electricity demand, power prices, and wind power production data for 2010 were used in conjunction with NREL simulated solar power production as input to the model. Currently, various PHS operational strategies are being tested to ascertain their effectiveness at firming and time shifting renewable generation. Preliminary results show the profound effects of increased penetration of renewable energy on an electric grid. The results also demonstrate a niche for even greater PHS operational flexibility, i.e. variable speed or unidirectional ternary machine (UTM) PHS.Copyright © 2012 by ASME
The Combinatorics of Cases and Word Order

The flexibility of word order varies from one language to another. In discussions of language complexity and word-order complexity in particular, it is important to find how many word orders the given grammatical structure can theoretically permit without creating syntactic ambiguity, even though not all of these orders are necessarily used in practice. Another question is what these orders are and how to determine them. The case system has to be taken into consideration because it is possible to make word-order freer if there are more cases available. These combinatorial questions are formalized for simple sentences using a model based on Dik’s Functional Grammar. Some special cases are completely solved, i.e. formulas are proved for the maximum number of word orders and their construction is given. The theoretical results are confirmed by several examples. Other cases and the general complexity of the problem are illustrated by additional examples.
Software quality: a curriculum postscript?

This paper addresses a central and critical issue in the development of computer software - its quality. The main thesis of the paper is that computer science faculty, in their design and implementation of curricula, do not devote sufficient attention to teaching their students how to develop high-quality software. As in industry, the most common and popular way of assuring the quality of programs is through software testing. In other words, quality is treated as an afterthought or as postscript in program development. The paper presents and discusses a quality model that can be used to incorporate a wide variety of quality assurance techniques within a curriculum. The model also presents a structured approach for introducing software testing into the educational environment. Finally, there is a discussion of how the model has been implemented using two current software process technologies, the PSP and the TSP.
Reflex control of sympathetic activity during ventricular tachycardia in dogs: primary role of arterial baroreflexes.

Background The determinants of hemodynamic outcome during ventricular tachycardia (VT) are not well understood. In the present study, we addressed the relative contributions of arterial and cardiopulmonary baroreflexes to the sympathetic and arterial pressure responses to VT or ventricular pacing (VP) in dogs with inducible VT. Methods and Results Responses of renal sympathetic nerve activity (RSNA), pulmonary capillary wedge pressure (PCWP), and mean arterial pressure (MAP) to induced VT or VP (220 to 280 beats per minute) were determined in 12 dogs with a healed anteroapical infarction and inducible VT and in 8 control dogs. The responses were determined with all reflexes intact, after selective denervation of either arterial or cardiopulmonary baroreflexes, and after combined denervation. Differences between intact and denervated conditions were used to assess the relative effects of each baroreflex. In the infarct group, responses during VT were comparable to those during VP. RSNA and PCWP increased s...
SU-FF-T-26: Comparison of PDR Iridium and LDR Cesium Through Monte Carlo Simulation

Purpose: Pulsed dose rate (PDR) 192Ir has been proposed as a substitute for intracavitary 137Cs brachytherapy because it radiobiologically mimics LDR treatments. Monte Carlo calculated doses to the ICRU 38 reference points show that PDR delivers a dose distribution that is comparable to that delivered by LDR 137Cs. Method and Materials: After validation of the Monte Carlo model using published data for a single source and radiochromic film measurements around a single shielded ovoid, the tandem and ovoid applicator system were modeled using Monte Carlo geometries. Treatment plans using the PDR source were created in Varian's Brachyvision software simulating the isodose shapes produced in a typical Cesium plan. These plans were recreated in Monte Carlo input files. A shielded and an unshielded version of each patient's treatment plan was created to ascertain the effect of the shields on the reference points. Results: The results showed that Monte Carlo calculations for the unshielded model to the standard ICRU 38 reference points agreed well with Brachyvision's calculations to these points. Results from the shielded model showed no significant affect to points A and B, but significant change to the bladder and rectal points. An average shielding effect of 12.7% was observed for the bladder point and an average effect of 29.4% was observed for the rectal point. The results were compared with data from a previous Cesium study involving the same patients. Doses to points A and B were similar. The shielding showed greater effectiveness with PDR for the bladder and rectum. Conclusion: A Monte Carlo model was developed to simulate representative clinical dose distributions from a PDR Iridium source in a shielded GYN applicator. The calculations demonstrate that PDR Iridium can be substituted for conventional LDR Cesium brachytherapy.
THE UTILITY OF APOLIPOPROTEIN A1, REMNANT LIPOPROTEINS, AND THE APOLIPOPROTEIN A1 REMNANT RATIO TO THE INCIDENCE OF CORONARY HEART DISEASE IN A PRIMARY PREVENTION COHORT OF AFRICAN AMERICANS OVERALL AND BY SEX: THE JACKSON HEART STUDY

Dyslipidemia plays a significant role in the progression of cardiovascular (CV) disease. The apolipoprotein (apo) A1 remnant ratio (apo A1/[VLDL3-C + IDL-C]) has recently been shown to be a strong predictor of death/MI risk among women >50 years undergoing angiography. However, whether this ratio is
Provenance of the Lower Ocoee Supergroup, eastern Great Smoky Mountains

Provenance and tectonic setting of clastic rocks of the Neoproterozoic Ocoee Supergroup were assessed using modes of detrital framework minerals, detrital feldspar chemistry, whole-rock geochemistry, heavy mineral assemblages and chemistry, and detrital zircon U-Pb geochronology. Putative source rocks comprising locally exposed Grenville basement were analyzed for comparison. Samples studied are primarily arkosic to subarkosic siltstones, sandstones, and minor conglomerate. Ternary tectonic discrimination diagrams indicate a continental basement uplift setting, although the mineralogically most mature Longarm quartzite indicates a continental interior setting. The range of detrital feldspar compositions among Ocoee units is comparable to feldspar in basement rocks. Orthoclase-rich detrital alkali feldspar predominates over detrital albitic plagioclase. Whole-rock normative Qz-Or-Pl values and trace-element abundances closely match those of local basement. Snowbird Group siltstones and sandstones contain high abundances of zircon, apatite, titanite, ilmenite, and epidote, which locally occur as concentrations of heavy minerals in discrete laminae. Zircon-tourmaline-rutile indices and titanite compositions are most consistent with a granitic source for these sediments. The majority of detrital zircon U-Pb ages are late Mesoproterozoic, with scattered late Neoproterozoic and Paleoproterozoic grains. All but one of the ∼1200 detrital zircons (at ca. 2000 Ma) can be accounted for by a local Blue Ridge basement magmatic source terrane. Archean detrital zircon ages are absent from the Ocoee detrital zircon age population. This absence is consistent with the general paucity of Archean grains in other Neoproterozoic Southern Appalachian clastic sequences. All data are consistent with a lithologically and geochronologically restricted, proximal, flank source for sediment filling a marginal continental rift. The Ocoee represents the first pulse of sediment dominated by Grenville-age zircon on the eastern Laurentian margin and serves as a major source of recycled zircon for Paleozoic clastic sequences in eastern Laurentia. The youngest detrital zircon age obtained from the basal Ocoee Wading Branch Formation (639 ± 8 Ma) provides a maximum depositional age for the Ocoee Supergroup and onset of rift-filling sedimentation in the intracontinental Ocoee basin.
Combined Molteno implantation and Pars Plana Vitrectomy for Neovascular Glaucomas

Abstract Ten patients underwent combined Molteno implantation and pars plana vitrectomy as the primary nonlaser surgical treatment of neovascular glaucoma associated with diabetic retinopathy (9 patients) or central retinal vein occlusion (1 patient). Combined surgery was performed most frequently because media opacities precluded adequate preoperative retinal ablation. Follow-up ranged from 3 to 43 (mean ± standard deviation, 18.0 ± 13.2) months. Six patients achieved final intraocular pressures less than 22 mmHg. Visual acuities remained the same or improved in four patients. Four patients had uncomplicated courses. Among the other patients, complications included: recurrent vitreous hemorrhage and retinal detachment (3 patients each); hyphema (2 patients); and tube block, extensive fibrin formation, epiretinal membrane, and total retinal necrosis (1 patient each).
Erythrocytes Inhibit Ligament Fibroblast Proliferation in a Collagen Scaffold

Anterior cruciate ligament (ACL) repair techniques have recently become of interest as less invasive treatment for ACL injuries are sought. In order to facilitate ACL repair, a provisional scaffold must persist in the wound site and become populated by productive fibroblasts. Previous studies have revealed that the presence of such a provisional scaffold is a primary difference between MCL and ACL healing profiles.1 In connective tissues that heal successfully (MCL), the provisional scaffold (clot) contains platelets, erythrocytes, and white blood cells (WBC). In contrast, in unsuccessful healing, as in the ACL, no clot is sustained in the wound site, so these potentially important healing components are absent. While there is an emerging body of work surrounding the role of the platelet in the provisional scaffold, there is less known about the role of the erythrocytes. There have been several studies completed recently that show that the presence of erythrocytes affects cell proliferation in vitro. Fredriksson et al.2 determined that proliferation of human lung fibroblasts was significantly inhibited when cultured with erythrocyte concentrations above 5 × 105 and 5 × 108 erythrocytes/ml, according to WST-1 (Water Soluble Tetrazolium) staining and DNA incorporation, respectively. Additionally, Jacobson et al.3 determined that human ACL fibroblast proliferation was significantly inhibited in a 3D collagen–platelet hydrogel with 1.5 × 109 erythrocytes/ml when compared to the control collagen–platelet hydrogel with no erythrocytes. In this work, we hypothesized that the concentration of erythrocytes in a provisional scaffold would have a significant effect on three of the major biological processes occurring in early wound healing, namely, cellular proliferation, collagen production, and scaffold contraction. We were most interested in testing erythrocyte concentrations in the range of their physiologic concentration in whole blood, which typically lies between 4.5 and 6.0 × 109 erythrocytes/ml in humans4,5 and 5.0 and 8.0 × 109 erythrocytes/ml in porcine models.6,7 In addition, we aimed to isolate the effect of erythrocytes by eliminating platelets and WBCs and studying a range of erythrocyte concentrations in platelet-poor plasma (PPP). We measured changes in DNA content, procollagen expression, and gel contraction over 3 weeks in collagen gels containing subphysiologic (SUB; 1 × 108 erythrocytes/ml), physiologic (PHYS; 1 × 109 erythrocytes/ml), and supraphysiologic (SUPRA; 1 × 1010 erythrocytes/ml) concentrations of erythrocytes.
Flow across the gastro‐esophageal junction: lessons from the sleeve sensor on the nature of anti‐reflux barrier

The principles of fluid flow are critical to the understanding of flow across the gastro-esophageal (GE) junction or gastro-esophageal reflux. The mechanism by which sleeve sensor measures lower esophageal sphincter (LES) pressure is also based on the principle of fluid flow across the GE junction and can provide important insights into the nature of anti-reflux barrier. We present arguments regarding the role of the length of LES, intra-abdominal length of the LES, flap valve at the GE junction and the angle of His on the strength of anti-reflux barrier. Our conclusion is that in the presence of normal anatomy of the GE junction (absence of hiatus hernia) the pressure at the GE junction is the most important determinant of the strength of anti-reflux barrier.
Interactions of mono- and divalent metal ions with aspartic and glutamic acid investigated with IR photodissociation spectroscopy and theory.

The interaction of metal ions with aspartic (Asp) and glutamic (Glu) acid and the role of gas-phase acidity on zwitterionic stability were investigated using infrared photodissociation spectroscopy in the spectral range 950-1900 cm(-1) and by hybrid density functional theory. Lithium ions interact with both carbonyl oxygen atoms and the amine nitrogen for both amino acids, whereas cesium interacts with both of the oxygen atoms of the C-terminus and the carbonyl oxygen of the side chain for Asp. For Glu, this structure is competitive, but a structure in which the cesium ion interacts with just the carbonyl oxygen atoms is favored and the calculated spectrum for this structure is more consistent with the experimentally measured spectrum. In complexes with either of these metal ions, both amino acids are non-zwitterionic. In contrast, Glu center dot Ca2+ and Glu center dot Ba2+ both adopt structures in which Glu is zwitterionic and the metal ion interacts with both oxygens of the C-terminal carboxylate and the carbonyl oxygen in the side chain. Assignment of the zwitterionic form of Glu is strengthened by comparisons to the spectrum of the protonated form, which indicate spectral features associated with a protonated amino nitrogen. Comparisons with results for glutamine, which adopts nearly the same structures with these metal ions, indicate that the lower Delta H-acid of Asp and Glu relative to other amino acids does not result in greater relative stability of the zwitterionic form, a result that is directly attributed to effects of the metal ions which disrupt the strong interaction between the carboxylic acid groups in the isolated, deprotonated forms of these amino acids.
EGF receptor antagonism inhibits in vivo angiogenesis and produces a survival benefit in pancreatic adenocarcinoma

Purpose. The purpose of this study was to evaluate epidermal growth factor receptor (EGFR) inhibition as treatment for pancreatic adenocarcinoma and to correlate biologic activity of EGFR with vascular endothelial growth factor (VEGF) and tumor angiogenesis. Methods. In vitro, HPAC, a moderately differentiated pancreatic cancer cell line, was assayed for EGFR gene and gene product using rtPCR and immunohistochemistry (IHC). In vitro growth kinetics with erlotinib, a small molecule tyrosine kinase inhibitor specific for EGFR, were determined at 50 and 100 μM concentrations. In vivo, 38 nude mice underwent orthotopic implantation of 106 HPAC cells and were randomized to (1) control (vehicle only), or (2) erlotinib (100 mg/kg/QD ip). IHC staining for EGFR, activated EGFR, VEGF, and CD31 was undertaken. Serum VEGF production in control and erlotinib-treated mice was evaluated by ELISA. Results. HPAC expressed both gene and gene product for EGFR. In vitro inhibition of tumor growth was significant at 48 and 72 h (P < 0.05, fig. Inset). Erlotinib-treated mice demonstrated a survival advantage, reduced tumor volume, weight, microvessel density, and decreased incidence of ascites, jaundice, and metastasis as compared to control (all P < 0.01). IHC showed decreased expression of EGFR, activated EGFR, and VEGF in erlotinib-treated mice. Conclusion. EGFR antagonism offers an in vivo survival benefit through EGFR inactivation and reduction in overall tumor angiogenesis possibly through decreased VEGF production. Download full-size image
Cloning of a cDNA encoding a constitutively expressed rat liver cytosolic aldehyde dehydrogenase.

Abstract The presence of a constitutively expressed aldehyde dehydrogenase (ALDH) in the rat liver cytosol is controversial (Tottmar et al., 1973; Lindahl and Evces, 1984; Berger and Weiner, 1977; Tank et al., 1981; Truesdale-Mahoney et al., 1981; Cao et al., 1989). A cDNA encoding a constitutively expressed rat liver cytosolic class 1 ALDH was cloned using a PCR-based strategy. The open reading frame consisted of 1503 nucleotides which encoded a protein of 501 amino acids. In order to compare the rat and human nucleotide sequences, we sequenced the entire open reading frame of a human liver cytosolic ALDH cDNA clone (Zheng et al., 1993). Rat liver constitutively expressed cytosolic ALDH was 99.7, 91.8, 89.0, and 83.8% identical to rat kidney, mouse liver, rat liver phenobarbital-inducible, and human liver cytosolic class 1 ALDH cDNAs, respectively. Northern blot analysis indicated that constitutively expressed rat cytosolic ALDH mRNA is expressed in lung, kidney, liver, skeletal muscle, and testis, with weak expression in heart and brain. These results strongly suggest that a constitutively expressed ALDH is present in rat liver cytosol.
Mass fraction spatiotemporal geostatistics and its application to map atmospheric polycyclic aromatic hydrocarbons after 9/11

This work proposes a space/time estimation method for atmospheric PM2.5 components by modelling the mass fraction at a selection of space/time locations where the component is measured and applying the model to the extensive PM2.5 monitoring network. The method we developed utilizes the nonlinear Bayesian maximum entropy framework to perform the geostatistical estimation. We implemented this approach using data from nine carcinogenic, particle-bound polycyclic aromatic hydrocarbons (PAHs) measured from archived PM2.5 samples collected at four locations around the World Trade Center (WTC) from September 22, 2001 to March 27, 2002. The mass fraction model developed at these four sites was used to estimate PAH concentrations at additional PM2.5 monitors. Even with limited PAH data, a spatial validation showed the application of the mass fraction model reduced the mean squared error (MSE) by 7–22%, while in the temporal validation there was an exponential improvement in MSE positively associated with the number of days of PAH data removed. Our results include space/time maps of atmospheric PAH concentrations in the New York area after 9/11.
Phosphine and phosphite intercalates of FeOCl

Abstract Triethylphosphine (TEP) and trimethylphosphite (TMP) have been intercalated into iron oxychloride to yield solids having one base molecule to six FeOCl units. Intercalation causes a significant expansion of the b-axis of the FeOCl lattice, corresponding to 3.96 and 6.47 A for the TEP and TMP intercalate, respectively. The isomer shift and quadrupole splitting data show a discontinuity at ≈220 K, from which it is inferred that the energetics of “guest” molecule binding in the van der Waals layer is on the order of 0.7 kcal mol−1. Fourier transform infrared spectra in KBr show that significant spectral changes in the C-P region occur on sample cooling, suggesting a direct interaction between the lone pair electrons of the phosphorus atom and the FeOCl lattice.
Acute Renal Failure after Cesarean Section

Urinary ascites is a rare diagnosis, commonly associated with bladder rupture. We present a case of intraperitoneal bladder injury following a Cesarean section with subsequent development of urinary ascites. Initial laboratory data with elevated serum creatinine and blood urea nitrogen (BUN) raised the suspicion for acute kidney injury due to the recent obstetrical procedure. This case highlights the importance of including intraperitoneal bladder injury with urinary ascites as a key differential in the workup of acute renal failure, particularly in the obstetric surgical setting. The rapid development of ascites with elevated serum BUN and creatinine should prompt work up for evaluating intraperitoneal bladder injury. Early diagnosis and treatment can yield gratifying results and avoid unnecessary workup of other causes of renal failure.
An accurate determination of the plutonium K-absorption edge energy using gamma-ray attenuation

Abstract The plutonium K-absorption edge energy is determined to be (121.795±0.014) keV by measuring the plutonium mass attenuation coefficient at eleven gamma-ray energies, including that of the 121.783 keV 152Eu gamma ray.
Magnetic dipole hyperfine structure in muonic atoms

Abstract The nuclear finite-size effect in the M1 hyperfine structure of muonic atoms of 93Nb and 139La has been studied experimentally. Systematic differences of the finite-size effect between nuclei in which the spin and the orbital angular momentum of the odd proton are parallel or anti-parallel are discussed.
SU‐E‐T‐853: Robust Multicriteria Optimization for IMPT

Purpose: A time and memory efficient projection algorithm for solving large scale IMPT treatment plans in a multicriteria setting has been published. However, the more conformal dose distribution of IMPT compared with that of IMRT comes with its sensitivity to uncertainties such as proton range uncertainty and set‐up error. To design a practically efficacious IMPT treatment system, robustness has to be accounted for to reduce the uncertainties. Methods: A nominal scenario and eight worst‐case scenarios (six extreme patient positions,proton beam undershoot and overshoot) are used to sample the uncertainty space. A solution can be constrained using a subset or all of the nine scenarios to be robust given any realization of the random errors. Moreover, the best quality plan can be pursued by navigating the Pareto space constituted by a number of optimal plans according to their own criteria of optimality. The method deals with very fine dose grid and tens of thousands modulated proton beamlets, therefore fully utilizes the potential of IMPT. Results: A base of skull case with 1mm dose‐grid resolution is applied to demonstrate the robustness of the solution. Compared to the plan obtained by the same problem formulation but considering only the nominal scenario, the DVH band of the robust plan is more stable, meaning the dose distribution varies little under even the worst scenario. The optimization for each task takes only seconds on a standard computer, making a computationally friendly interface possible to the planner. Conclusions: The uncertainty pertinent to the IMPT procedure can be reduced during treatment planning by optimizing some best plans that emphasize different treatment objectives and then interactively seeking for a compromised one from the Pareto solution space. The method works very fast for rather fine dose grid and sufficiently large beamlet numbers, thus streamlines the IMPT treatment process.
Fibrinogen is an antioxidant that protects β-lipoproteins at physiological concentrations in a cell free system

Abstract Oxidation of β-lipoproteins has been linked to the development of arteriosclerosis. Using a copper mediated cell free system to oxidize β-lipoproteins, we found that β -lipoproteins isolated from plasma were less susceptible to oxidation than lipoproteins from serum and that this was probably due to inhibition by fibrinogen, because removal of fibrinogen from plasma enhanced oxidation, while addition of fibrinogen restored inhibition. Fibrinogen inhibited conjugated diene formation and peroxide formation assayed by the xylenol orange assay (absorbance±confidence interval: 0.155±0.007 with fibrinogen vs 0.255±0.014 without) and retarded copper mediated oxidation of apolipoproteins in low density lipoproteins, reducing the distance of electrophoretic migration by 5 mm. The effect of fibrinogen was not due to chelation of copper, since it provided protection when hydrogen peroxide was substituted for copper as an oxidizing agent. At normal physiological concentration equivalents, fibrinogen showed superior antioxidant properties compared to albumin, melatonin, vitamin C and vitamin E and was superior to the vitamins when compared on an equimolar basis. Other studies have shown the fibrinogen to be more oxidizable than other major plasma proteins and to inhibit peroxide production. Because of its high mass concentration, we postulate fibrinogen is an important antioxidant protecting β-lipoproteins in plasma and that it may be important in protecting lipoproteins in tissue spaces.
Explanations for the eclipse of United States public housing development: 1961–80

Abstract Despite the Reagan cutbacks in US housing programs, the public housing program's role in housing development had been greatly diminished in the 20 years prior to 1981. The diminution of public housing development over this time was not caused by insufficient need for public housing or because the program had failed in providing decent, affordable housing for low‐income households. Instead, public housing's decline as a source of new subsidised housing appears due substantially to factors external to the program. These factors include: 1) growing acceptance, by both government and business, of direct business participation in the delivery of government social services, including housing; 2) increased use of federal monies, especially in the 1960s, to subsidise the construction industry, with a consequent relative decline in resources for programs housing low‐income households; 3) the faltering image of the public housing program, which loomed much larger than the reality, 4) delays in construction...
Characterization of 4H-SiC Epitaxial Layers and High-Resistivity Bulk Crystals for Radiation Detectors

Defect and electrical characterization of bulk semi-insulating (SI) 4H-SiC crystals and SI and n-type 4H-SiC epitaxial layers grown by chemical vapor deposition (CVD) on highly doped (0001) 4H-SiC substrates is reported. Optical microscopy, electron beam induced current (EBIC) imaging, current-voltage ( $I$ – $V$ ) measurements, thermally stimulated current (TSC) spectroscopy (94 K–620 K), Hall effect, and van der Pauw measurements have been conducted for characterization and defect correlation studies. Both epitaxial layers exhibited relatively shallow levels related to Al, B, $L$ - and D-centers. Deep level centers in the n-type epitaxial layer peaked at ${\sim} 400$ K ( $E_{a} \sim 1.1$ eV), and ${\sim} 470$ K were correlated with $IL_{2}$ defect and 1.1 eV center in high-purity bulk SI 4H-SiC. The SI epitaxial layer exhibited peak at ${\sim} 290$ K ( $E_{a} = 0.82\hbox{--}0.87$ eV) that was attributed to $IL_{1}$ and HK2 centers, and at ${\sim} 525$ K that was related to intrinsic defects and their complexes with energy levels close to the middle of the band-gap. Results of EBIC and optical microscopy showed segregation of threading dislocations around comet tail defects in the n-type epitaxial layer. The $I$ – $V$ characteristics of the devices on SI epitaxial layer exhibited steps corresponding to the ultimate trap filling of deep centers. The high-temperature resistivity measurements of bulk SI 4H-SiC sample revealed resistivity hysteresis that was attributed to the filling of the deep-level electron trap centers. The responsivity of the n-type epitaxial 4H-SiC detector in the soft X-ray energy range is reported for the first time.
Myosin conformation and enzymatic activity: Effect of chloroform, diethyl ether and halothane on optical rotatory dispersion and ATPase

Abstract Optical rotatory dispersion (ORD) of myosin from white skeletal muscle of rabbit showed significant change between 230 and 250 nm after exposure to commonly used concentrations of the anesthetics halothane (2-bromo-2-chloro-1,1,1-trifluoroethane), chloroform and diethyl ether; at 23 °C (pH 7.0) the average [m′] 233 increase was 8%. EDTA (K+-activated ATPase of myosin was depressed by each of the three anesthetics. Ca2+-activated ATPase was inhibited by chloroform. In contrast, low concentrations of halothane and all tested concentrations of diethyl ether had little effect on the Ca2+-activated ATPase; a 3-fold increase in concentration of halothane caused a 25% increase in the ATPase activity. The effects of commonly used clinical concentrations of the 3 drugs were reversible. No evidence was found that halothane, chloroform and diethyl ether were bound to ATP in aqueous solution.
Two dimensional radiated power diagnostics on Alcator C-Mod.

The radiated power diagnostics for the Alcator C-Mod tokamak have been upgraded to measure two dimensional structure of the photon emissivity profile in order to investigate poloidal asymmetries in the core radiation. Commonly utilized unbiased absolute extreme ultraviolet (AXUV) diode arrays view the plasma along five different horizontal planes. The layout of the diagnostic set is shown and the results from calibrations and recent experiments are discussed. Data showing a significant, 30%–40%, inboard/outboard emissivity asymmetry during ELM-free H-mode are presented. The ability to use AXUV diode arrays to measure absolute radiated power is explored by comparing diode and resistive bolometer-based emissivity profiles for highly radiative L-mode plasmas seeded with argon. Emissivity profiles match in the core but disagree radially outward resulting in an underprediction of Prad of nearly 50% by the diodes compared to Prad determined using resistive bolometers.
Predictability of mesoscale phenomena

The Symposium on Predictability of Mesoscale Phenomena (DM3), held at the 1983 IUGG General Assembly, addressed two questions: (1) What mechanisms control the predictability of mesoscale phenomena, in particular quantitative precipitations? (2) Over what time interval can these events be predicted? The papers presented were related more to the first question than to the second. Two sessions were organized. Session I was reserved for the meso-α type studies and session 2 for the meso-β type studies. Space does not permit discussion of all contributions.