cssi/SciSciGPT-SciSciNet huggingface dataset:
Pyrimidine Biosynthesis in Lactobacillus leichmannii

Tracer studies of pyrimidine biosynthesis in Lactobacillus leichmannii (ATCC 7830) indicated that, while aspartate is utilized in the usual manner, the guanido carbon of arginine, rather than carbon dioxide, is utilized as a pyrimidine precursor. The guanido carbon of arginine also contributes, to some extent, to the carbon dioxide pool utilized for purine biosynthesis. The enzyme of the first reaction leading from arginine to pyrimidines, arginine deiminase, was investigated in crude bacterial extracts. It was inhibited by thymidylic acid and purine ribonucleotides, and to a lesser extent by purine deoxynucleotides and deoxycytidylic acid. Under the assay conditions employed, a number of nucleotides had no effect on the enzyme activity of the aspartate transcarbamylase of L. leichmannii. Growth of the cells in media containing uracil, compared to growth in media without uracil, resulted in a four- to fivefold decrease in the concentrations of aspartate transcar-bamylase and dihydroorotase and a twofold increase in the concentration of arginine deiminase, as estimated from specific enzyme activity in crude extracts of the cells. A small increase in specific enzyme activity of ornithine transcarbamylase and carbamate kinase was also observed in extracts obtained from cells grown on uracil. No appreciable change in concentration of any of the five enzymes studied was detected when the cells were grown in media containing thymidine or guanylic acid. A hypothetical scheme which suggests a relationship between the control of purine and pyrimidine biosynthesis in this bacterium and which is consistent with the experimental results obtained is presented.
Photo-hall measurements of high-density photoexcited electrons in Hg1−xCdxTe

The transport properties of electrons in low-temperature Hg1−xCdxTe (x ≈ 0.2) have been studied using photo-Hall techniques, where a CO2 laser is used to produce high electron-hole plasma densities. At high excitation levels, the mobility is found to decrease monotonically with increasing carrier density. The data is compared with a transport theory for nonparabolic bands which employs scattering cross sections derived by the partial-wave phase shift method. The effects of electron-hole scattering, screening by the photoexcited electrons and holes and disorder scattering are considered. It is shown that dynamic hole screening of the electron-hole interactions must be accounted for in the analysis in order to obtain good agreement between theory and experiment.
Dynamics of Democratic Satisfaction in Transitional Settings: Evidence from a Panel Study in Uganda

How do campaigns and elections affect evaluations of democracy in transitional settings? Little research has been conducted on this topic in transitional settings, where citizens’ evaluations of regime performance might be especially fluid and where popular dissatisfaction with democratic institutions could inhibit political development. Furthermore, previous studies’ reliance on cross-sectional data has made it difficult to make valid causal inferences in this area. Drawing upon unique data from the 2010–2011 Uganda Campaign Panel Study, the first panel on campaign effects in Africa, we measure changes in individuals’ satisfaction with democracy. We find that individuals who supported a losing presidential candidate are more likely to show decreases in satisfaction over the course of the campaign than those who supported the winner. Importantly, we find that previous political participation does not necessarily result in increases in democratic satisfaction: rather, it is associated with decreased satisfaction for losers. Finally, there is no evidence that declines in satisfaction with democracy are associated with decreased support for democracy as a regime. This study furthers understanding of political development by identifying factors that affect how citizens evaluate their political regime.
Dorsal Penile Nerve Block Prior to Inflatable Penile Prosthesis Placement: A Randomized, Placebo‐Controlled Trial

ABSTRACT Introduction Dorsal penile nerve block (DPNB) has been previously shown to provide effective analgesia for penile surgeries. To date, few studies have examined the role of DPNB prior to inflatable penile prosthesis (IPP) implantation. Aim The purpose of this study was to assess the efficacy of local penile nerve block prior to IPP implantation for postoperative pain control. Main Outcome Measures The primary outcome was postoperative pain rated using the visual analog scale (VAS). Secondary outcome measures included total narcotic usage during hospitalization. Methods Institutional Review Board approval was obtained. Patients with erectile dysfunction scheduled for IPP implantation were approached for study participation. Patients were excluded if they had a previous IPP scheduled for revision or replacement or were undergoing additional procedures during the same operative session. Patients were then randomized to either DPNB with 1% lidocaine and 0.5% bupivacaine without epinephrine or injectable saline placebo. Only the resident surgeon assisting in the case was aware of randomization. All procedures were performed by a single surgeon (C.C.C.). Postoperatively, patients were asked to rate their pain using a VAS hourly while in recovery, at 4 hours, and at 23 hours postoperatively. Total narcotic usage was also measured. Results A total of 30 patients underwent randomization with 15 patients in each group. Baseline demographic data were similar in each group. There was a significant reduction in pain in the immediate postoperative period and at 4 hours after surgery in the treatment group when compared with placebo (VAS 2.5 vs. 5.3, P = 0.009 at 0 hours; VAS 2.8 vs. 5.1, P = 0.011 at 4 hours). Narcotic usage was similar among both groups. There were no perioperative or early postoperative complications in either group. Conclusions DPNB is safe and effective for reducing pain in the early postoperative period following penile prosthesis implantation. Raynor MC, Smith A, Vyas SN, Selph JP, and Carson CC, III. Dorsal penile nerve block prior to inflatable penile prosthesis placement: A randomized, placebo‐controlled trial. J Sex Med 2012;9:2975–2979.
Intraventricular 6-hydroxydopamine increases thyrotropin-releasing hormone (TRH) content in regions of rat brain.

Abstract Rats were given intraventricular (ivt) injections of various doses (50–400 μg, hydrobromide salt) of 6-hydroxydopamine (6-OHDA) and killed 1, 3 or 6 days later. Brains were removed, dissected into 11 regions, and the thyrotropin-releasing hormone (TRH) content of each region was measured by radioimmunoassay. 6-OHDA (400 μg) caused significant elevations in the TRH content of 6 regions: olfactory bulb, anterior cortex, brainstem, posterior cortex, hippocampus, and amygdala-piriform cortex. The magnitude of these increases ranged from 59% in olfactory bulb to 497% in hippocampus and was, in all cases, greatest at 3 days. These results suggest that the TRH content of certain brain regions may be regulated by catecholamine neurotransmitters.
Mapping prison proliferation: Region, rurality, race and disadvantage in prison placement

Perhaps the leading perspective on how and where prisons are located stems from the perspective of the prison industrial complex (PIC). Implicit, if not explicit, in the PIC perspective is the notion that Black and Hispanic prisoners are exploited for the benefit of poor, unemployed, White prison towns. Unfortunately, however, there has been a shortage of empirical scrutiny of this central notion. This paper examines this claim with a rare event logistic regression analysis of 176 new prison placements across 13,155 rural places in the 1990s in the US. In contrast to the PIC perspective, prison towns are disproportionately southern and poor, and have a larger population with a greater share of Blacks and Hispanics. The analysis yields three further challenges to the PIC perspective on prison towns. First, findings suggest rural prison placement does not cause racial and economic inequality as much as prison siting results from concentrated rural disadvantage. Second, there is not one prototypical prison town. Instead, there are typologies of prison towns based on US region, race, town population size, race, prior proximate prison, and SES. Lastly, future studies should consider the theoretical and methodological implications of rural concentrated disadvantage in measuring prison impact.
AUTOMATED CLASSIFICATION OF CONSTRUCTION PROJECT DOCUMENTS

The number of documents generated in a construction project and stored in interorganizational information systems is significant. Since a large percentage of these project documents are generated i...
Pushing around a robot: Force-based manual control of the six-legged walking robot LAURON

Robots are built to assist people. Up to now the circle of people benefiting is still rather small because operating a robot is a very difficult task. To enable untrained people to operate a robot, an intuitive user interface has to be provided. Besides enlarging the number of people which are actually able to operate the robot, the operators are less burdened by controlling the robot and therefore are able to concentrate better on the task they actually have to perform. This paper presents a method of applying the maybe most intuitive modality of control: the operator can give commands to the six-legged walking robot LAURON by pushing or pulling its body. To achieve this the robot's 18 joint torques are calculated based on the motor currents. These are then transformed and merged in a 6D force vector corresponding to LAURON's CoG. This vector is finally fed into a classifier which identifies the user's intention out of a set of possible commands and triggers corresponding behaviors.
Low pressure chemical vapor deposition of fluorine-doped indium oxide films from an indium alkoxide complex

Fluorine-doped indium oxide films are of interest as a transparent conducting material. Polycrystalline indium oxide films were deposited at 400–550 °C in a low-pressure chemical vapor deposition process from In[OCMe(CF3)2]3(H2N-t-Bu) and O2 precursors. The films deposited at ≤500 °C contained 2–3 atom% fluorine while the film deposited at 550 °C had no detectable fluorine incorporation (by X-ray photoelectron spectroscopy with sputtering). Films deposited on quartz (≈1800 A thickness) showed >85% transmittance in the 400–800 nm region and had band gaps of 3.65–3.75 eV. Resistivities of 1.25 × 10−2–9.96 × 10−3 Ω cm were measured for the as-deposited films. The resistivities of films grown on silicon decreased markedly after annealing to values as low as 1.43 × 10−3 Ω cm.
A dynamic accessibility protocol for replicated databases

Abstract In this paper, we present a protocol for managing replicated data in a distributed system. The protocol tolerates both site and communication failures even when they lead to partitioning. Two of the main features of the protocol are the availability levels it provides, and the low communication costs required of user transactions to attain these levels. In particular, an object may be accessible even after the failure of most of the sites where copies of the objects reside. Furthermore, an object can be read by accessing a single copy, and in general, the cost of executing operations is less than that required by protocols that attain similar levels of availability. Finally, the protocol provides the database designer with the flexibility of determining both the degree of availability as well as the cost of executing the different operations of a data object.
Bulk heterojunction organic photovoltaic devices based on phenyl-cored thiophene dendrimers

Bulk heterojunction organic photovoltaic devices have been fabricated by blending phenyl-cored thiophene dendrimers with a fullerene derivative. A power conversion efficiency of 1.3% under simulated AM1.5 illumination is obtained for a four-arm dendrimer, despite its large optical band gap of 2.1eV. The devices exhibit an increase in short-circuit current and power conversion efficiency as the length of the arm is increased. The fill factors of the devices studied are characteristically low, which is attributed to overly uniform mixing of the blend.
Affinity chromatography of β-galactosidase on control-led-pore glass derivatives

Abstract Several controlled-pore glass (CPG) derivatives were examined as supports for the affinity chromatographic purification of the enzyme β-galactosidase. The competitive inhibitor p-aminophenyl-β- d -thiogalactopyranoside was coupled to an acid and a malonic acid derivative of 750-A alkylamine CPG of 80–120 mesh and to an azelaic acid derivative of 550-A alkylamine CPG of 40–80 mesh. The latter derivative exhibited particularly good load capacity and separation efficiency; however, both arm lengths were effective. Hydrophobic interactions between the arm and the enzyme contribute to the separation.
A Deep Very Large Array Radio Continuum Survey of the Core and Outskirts of the Coma Cluster

We present deep 1.4 GHz Very Large Array radio continuum observations of two ~0.5 deg2 fields in the Coma cluster of galaxies. The two fields, Coma 1 and Coma 3, correspond to the cluster core and southwest infall region and were selected on account of abundant preexisting multiwavelength data. In their most sensitive regions the radio data reach 22 μJy rms per 44 beam, sufficient to detect (at 5σ) Coma member galaxies with L 1.4 GHz = 1.3 × 1020 W Hz–1. The full catalog of radio detections is presented herein and consists of 1030 sources detected at ≥5σ, 628 of which are within the combined Coma 1 and Coma 3 area. We also provide optical identifications of the radio sources using data from the Sloan Digital Sky Survey. The depth of the radio observations allows us to detect active galactic nucleus in cluster elliptical galaxies with Mr < –20.5 (AB magnitudes), including radio detections for all cluster ellipticals with Mr < –21.8. At fainter optical magnitudes (–20.5 < Mr –19), the radio sources are associated with star-forming galaxies with star formation rates as low as 0.1 M ☉ yr–1.
Combined Modality Therapy for Rectal Cancer: The Relative Value of Posttreatment Versus Pretreatment CEA as a Prognostic Marker for Disease Recurrence

To evaluate the prognostic significance of the first postsurgery carcinoembryonic antigen (CEA) level in patients with locally advanced rectal cancer treated with neoadjuvant chemoradiation (nCRT) and total mesorectal excision. A total of 100 patients underwent nCRT and had baseline and posttreatment CEA levels recorded within 6 months of surgery. The median radiotherapy dose was 50.4 Gy. Eighty-six patients received adjuvant 5-fluorouracil-based chemotherapy. Prognostic factors were analyzed for possible associations with freedom from failure (FFF) by univariate and multivariate analyses. Median follow-up was 30 months. The median CEA (ng/ml) levels at baseline before nCRT, after nCRT, and after total mesorectal excision were 3.6, 1.7, and 1.3, respectively. Pathologic complete response was observed in 22%. FFF at 36 months was 78%. Local failure and distant failure occurred in 4 and 20% of the patients, respectively. On univariate analysis, pathologic complete response, margin status, and both pretreatment and postsurgery CEA levels were associated with recurrence (all P 2.5 ng/ml have higher rates of recurrence and may warrant closer surveillance.
Temperature Dependence of theCPN-1 Model and the Analogy with Quantum Chromodynamics

The two-dimensional CPN-1 model — a simple field-theoretic analogue of four-dimensional quantum chromodynamics (QCD) — is analysed and reviewed. The major themes are the temperature dependence of the CPN-1 model, and the analogy between CPN-1 and QCD. A detailed treatment of the 1/N approximation of the CPN-1 model is given. The main results emerging from this approximation are discussed at length. These are: asymptotic freedom, dimensional transmutation, confinement and topological charge nonquantization at zero temperature T = O, screening and topological charge quantization at finite temperature T. The analogy with QCD is explained in detail. A new, qualitative, analysis of the CPN-1 model at finite temperature is introduced. This approach exploits the conformal invariance of the model to “heat” an arbitrary CPN-1 field from T = O to finite temperature. This is achieved by conformal-transforming the flat Euclidean space-time of the T = O theory to the cylindrical space-time of the finite temperature theory.
Cell surface γ-glutamyl transpeptidase in live cultures

A physiological assay for measuring surface accessible gamma-glutamyl transpeptidase activity in adherent, living cultures is described. Cell surface transpeptidase activity remained linear throughout a 60-min time course over a wide range of cell densities. In addition, the assay conditions have neither acute nor long-term effects on cell growth potential, cellular morphology, or cell surface transpeptidase activity levels. As a result, cell surface transpeptidase activity can be continually evaluated in the same cultures during proliferation. The assay appears to be specific for cell surface transpeptidase and can be used to study the partitioning of the enzyme between substrate-accessible and substrate-inaccessible pools. This method utilizes an automated microtiter plate reader for the spectrophotometric quantification of small aliquots removed from cultures incubated with the chromogenic substrate L-gamma-glutamyl-p-nitroanilide. The use of a microtiter plate autoreader and the minimal handling of the cells permit a large number of cultures to be assayed with a substantial reduction in the time required to measure surface transpeptidase activity. The assay described is a nondestructive means for studying cell surface-accessible gamma-glutamyl transpeptidase catalytic activity within the microenvironment of the living culture.
Inertia Effects in Infra-Red Sensitive Phosphors†

Measurements are reported on the time required for an infra-red phosphor to acquire maximum brightness when exposed to infra-red radiation. This time becomes smaller as the infra-red intensity is increased, but there seems to be no simple relationship between the two quantities. The data given are for phosphors composed of strontium sulfide or selenide activated with europium and samarium. The brightness of strontium sulfide activated with cerium and samarium reaches its maximum value in something less than 10−4 sec., a time too short to be measured by the present apparatus.Results on some samples seem to indicate the existence of two simultaneous processes. An appreciable fraction, often about one-half, of the final brightness is reached in less than 10−4 sec., while the ultimate value is approached in a much more leisurely fashion.
What Can Video Games Teach Us About Teaching Reading

James Gee has suggested that video games can teach us important lessons about learning and that we can learn about teaching from these games. Reading research and the words of the author's daughter are the basis of an exploration of the learning principles Gee identifies. He explains that video games are successful in engaging children and teaching them the strategies they need to be successful and that high-quality reading instruction should do the same. In this article, eight of the learning principles identified by Gee are applied to the teaching of reading. The first two explore insights about learners and the conditions that foster learning. The next three principles address general understandings about how learning occurs. The final three principles have direct implications for teaching. The article raises important questions about learning, engagement, and identity, as well as promoting problem solving and strategic activity in reading.
Recombinant expression and partial characterization of the human formyl peptide receptor

FMLP-receptor DNA was expressed in Escherichia coli. The expressed product could specifically bind FMLP. This is the first-reported expression of a functional FMLP receptor in Escherichia coli. We confirm that receptor glycosylation is not essential for ligand binding. A deletion mutant did not bind FMLP, suggesting that the deleted portion plays a role in ligand binding.
Relation of behavior of copepod juveniles to potential predation by omnivorous copepods: an empirical-modeling study

An empirical-modeling study was carried out to examine the motion behavior of cope- pod nauplii in relation to their potential predation by omnivorous copepods. First, video observations were taken on the encounters of Centropages velificatus, Paracalanus aculeatus, Paracalanus quasi- modo and Temora stylifera nauplii with free-swimming adult females of C. velificatus. By examining each female's behavior, the observed encounters were arranged into 3 categories: (1) quasi-steady, (2) unsteady, and (3) unsteady with body rotation. We found that a wide spectrum of motion behaviors contributes to the generation of hydrodynamic signals. A hydrodynamic model was developed to analyze 4 encounters under the quasi-steady category. The model takes into account the effects of the finite-sized body morphology and the no-slip boundary condition imposed at the surface of the nauplius. Therefore, the model is able to calculate the tip-base velocity differences, as well as the tip-base shear rates over the length of the setae of the A1 (first antennae) of the nauplii, resulting from the flow disturbances generated by a steadily approaching C. velificatus female. When the tip-base shear rates around its A1 setae reached the range of 3.0 to 4.8 s -1 , a C. velificatus nauplius, moving only occasionally, detected the approaching female copepod. By contrast, a P. quasimodo nauplius and a T. stylifera nauplius, both moving continuously by beating their cephalic appendages, did not detect the female, even when the tip-base shear rates reached the range of 5.2 to 6.2 s -1 for the former and 8.4 to 11.4 s -1 for the latter. The modeling results also reveal the cause of the difference in the sensitivity to hydrodynamic signals. Nauplii moving only occasionally have a much weaker noise field (originating from the naupliar self-generated flow) around their A1 setae than those moving their cephalic appendages continuously to achieve a smooth and continuous motion pattern, and therefore are better suited to perceiving nearby predators. This model provides a mechanistic under- standing as to why continuously moving nauplii are preyed upon at a higher rate than those moving intermittently.
CD30-Positive EBV–Associated Diffuse Large B-Cell Lymphoma Occurring After Immunosuppressive Therapy for T-Cell Prolymphocytic Leukemia

We describe the case of a 64-year-old man who developed diffuse large B-cell lymphoma (DLBCL) in less than a year after he was diagnosed and treated for T-cell prolymphocytic leukemia (T-PLL). At the time of diagnosis of T-PLL he had a white blood cell count (WBC) of 38.2×10(9)/L and only few small lymph nodes were identified on physical examination. Hepatosplenomegaly or skin lesions were not present. Peripheral blood examination was remarkable for 91% circulating prolymphocytes, which by flow cytometry immunophenotypic analysis were CD2, CD3, CD5, and CD7 positive and coexpressed CD4 and CD8 (absolute number, 33.4×10(9)/L). T-cell receptor (TCR) β and γ genes rearrangements were identified by polymerase chain reaction (PCR). The patient underwent chemotherapy, but did not completely achieve cytogenetic remission. Nine months after his diagnosis of T-PLL, he underwent surgical excision of a new 7 cm left inguinal mass, and was diagnosed with CD30 positive Epstein-Barr Virus (EBV)-associated DLBCL.
Elastic-plastic memory and kinematic-type hardening

Abstract In this article it is proposed that the classical plasticity concept of kinematic hardening is much more general and descriptive of plastic deformation in metals than has heretofore been acknowledged. Furthermore it is shown how microstructural ideas involving dislocation micro-mechanisms do, when properly coupled to the classical continuum theories, prescribe not one but several forms of kinematic hardening and that these forms are suggestive of strain hardening mechanisms on the micro as well as on the macroscale. Experimental illustration of two forms of this hardening are given. Finally, it is shown that kinematic type hardening involves a sort of plastic memory and that to describe such a memory state from dislocation theory a more complete description of dislocation densities than is normally used is required.
DNA-DNA hybridization analysis of Streptococcus thermophilus plasmids

Five of the nine known plasmid DNAs of Streptococcus thermophilus ranging from 2.2 kbp to 14.7 kbp in molecular size, were found to share homologous sequences as evidenced by DNA-DNA hybridization analyses. The four other S. thermophilus plasmids also lacked homology with one another implying that they may represent unique DNA homology groups. The lack of homology between the S. thermophilus probe (pER8, 2.2 kbp) and plasmids of Lactococcus lactis, L. cremoris and lactobacilli also implied a fundamental difference in the origins of plasmids of thermophilic and mesophilic lactic acid bacteria.
The effect of body mass index on PSA levels and the development, screening and treatment of prostate cancer

The prevalence of both obesity and prostate cancer are increasing in the US. Recently, there has been keen interest in the relationship between obesity and the biology of cancers, including prostate cancer. This article reviews the current literature regarding body mass index (BMI) and its relationship with various clinical aspects of prostate cancer, including its incidence, screening, diagnosis and treatment. Despite several biological mechanisms that potentially link obesity to prostate cancer, the effects of obesity on serum PSA levels and prostate volume, and the subsequent effects on the detection of prostate cancer, are not consistent according to the available literature. Additionally, the epidemiologic data for the incidence of prostate cancer in obese and non-obese populations are conflicting. Treatment of prostate cancer in obese populations is problematic, but data on the ability to overcome these difficulties are unclear. It is difficult to determine whether oncologic and functional outcomes in obese patients differ substantially from those in non-obese patients. Separating the contributions of technical issues from potentially different tumor biologies is not currently possible. Hopefully, the increasing focus on these two highly prevalent health problems might further elucidate their complex relationship.
Computed tomographic imaging characteristics of the normal canine lacrimal glands

The canine lacrimal gland (LG) and accessory lacrimal gland of the third eyelid (TEG) are responsible for production of the aqueous portion of the precorneal tear film. Immune-mediated, toxic, neoplastic, or infectious processes can affect the glands directly or can involve adjacent tissues, with secondary gland involvement. Disease affecting these glands can cause keratoconjunctivitis sicca, corneal ulcers, and loss of vision. Due to their location in the orbit, these small structures are difficult to evaluate and measure, making cross-sectional imaging an important diagnostic tool. The detailed cross-sectional imaging appearance of the LG and TEG in dogs using computed tomography (CT) has not been reported to date. Forty-two dogs were imaged, and the length, width, and height were measured and the volume calculated for the LGs & TEGs. The glands were best visualized in contrast-enhanced CT images. The mean volume of the LG was 0.14 cm3 and the TEG was 0.1 cm3. The mean height, width, and length of the LG were, 9.36 mm, 4.29 mm, and 9.35 mm, respectively; the corresponding values for the TEG was 2.02 mm, 9.34 mm, and 7.90 mm. LG and TEG volume were positively correlated with body weight (p < 0.05). Contrast-enhanced CT is a valuable tool for noninvasive assessment of canine lacrimal glands.
Fluorescence anisotropy studies of orientational order of Langmuir-Blodgett multilayers

Abstract Langmuir-Blodgett multilayer films of cadmium stearate labeled with 3-(7-nitrobenz-2-oxa-1,3-diazol) fluorescence probes have been fabricated and studied by fluorescence microscopy and steady state anisotropy measurements. The results indicate that there is a decrease in fluorescence anisotropy with number of layers which saturates at about 10 layers. This decrease may be modeled as a decrease in orientational order of the fluorescence probes in the multilayers. A simplified model is used to obtain values for the 〈P2〉 and 〈P4〉 order parameters as a function of thickness. 〈P2〉 is 0.4 and does not change with thickness. 〈P4〉, however, decreases from 0.1 for a monolayer to 0.04 for a 9-layer film.
Parallel search for LTL violations

Recent advances in parallel model checking for liveness properties achieve significant capacity increases over sequential model checkers. However, the capacity of parallel model checkers is in turn limited by available aggregate memory and network bandwidth. We propose a new parallel algorithm that sacrifices complete coverage for increased capacity to find errors. The algorithm, called BEE (for bee-based error exploration), uses coordinated depth-bounded random walks to reduce memory and bandwidth demands. A unique advantage of BEE is that it is well suited for use on clusters of nondedicated workstations.
Effect of interventions that increase cyclic AMP levels on susceptibilty to ventricular fibrillation in unanesthetized dogs

Although the autonomic nervous system has been implicated in the formation of ventricular fibrillation, the precise mechanism by which this is mediated remains undetermined. In particular, the role of second messengers, generated by beta-adrenoceptor activation, has been postulated to mediate the pro-arrhythmic effects of the sympathetic nervous system. Thus, a 2 min occlusion of the left circumflex coronary artery was initiated during the last minute of exercise in canines with healed myocardial infarctions (produced by ligation of left anterior descending artery). Fifteen dogs were found to be susceptible to the formation of ventricular fibrillation while 17 animals were resistant. Nine resistant dogs were treated with the phosphodiesterase inhibitor isobutylmethyl xanthine (IBMX, 1 mg/kg) in combination with an infusion of 8-bromo-cAMP (100-150 micrograms/kg/min beginning 45 min prior to exercise). Heart rate and left ventricular dP/dtmax significantly increased, but failed to elicit, arrhythmias during the exercise and ischemia test. Nine resistant animals were also treated with the adenylate cyclase activator forskolin, (100 micrograms/kg), which provoked the same hemodynamic changes as the cyclic AMP infusion but also failed to induce ventricular fibrillation. Both forskolin (n = 3) and IBMX (n = 3) induced large increases in myocardial cAMP levels (control 5.2 +/- 0.5, forskolin 8.1 +/- 0.8 pmol/mg non-collagen protein; control 5.0 +/- 0.8, IBMX 6.8 +/- 0.3 pmol/mg non-collagen protein). Ten resistant animals were treated with the beta-adrenoceptor agonist isoproterenol (1-10 micrograms/kg/min), which failed to cause ventricular fibrillation despite significant increases in the hemodynamic parameters described above. Finally, experiments were repeated after 8-bromo-cAMP infusion and IBMX pretreatment in 8 susceptible animals with pharmacologic denervation (atropine+propranolol+prazosin). In spite of hemodynamic increases indicative of an increase in myocardial cyclic AMP levels, arrhythmias were not re-introduced. These data suggest that changes in cAMP may not be responsible for ventricular fibrillation in this model of sudden cardiac death.
Drumlins of the Puget Lowland, Washington State, USA

Abstract The last advance of the Puget Lobe, a piedmont glacier that extended southward down the axis of the fjord-like Puget Lowland from the main mass of the Cordilleran Ice Sheet, produced an extensive drumlin field approximately 170 km in length and nearly 100 km wide. The timing of both the advance and retreat of the lobe across the region is well constrained, and took no more than a total of 1500 years. In the southern portion of the field, drumlin axis orientations are more closely perpendicular to recessional ice margin positions than to the reconstructed ice-maximum surface contours. This suggests that the drumlin field was formed in a time-transgressive manner as the ice front retreated from south to north, and that each of the numerous recessional phases was characterised by a narrow drumlin-forming zone that extended no more than a few kilometres back from the margin. This would also indicate that only a few decades were required for the formation of individual drumlins in the Puget Lowland. The drumlin forms are composed of compact till that overlies and truncates a 100 m thick sand and gravel unit. The sand has been interpreted as proglacial outwash, originally formed as a continuous blanket deposited in front (south) of the advancing Puget Lobe. It forms the main component within the lower 10–50% of the drumlin till, while farther-travelled components appear in progressively greater proportion with increasing height above the contact. The drumlins are thus interpreted as being of constructional origin. Evidence of minor subglacial meltwater activity occurs in the form of scattered, discontinuous water-sorted lenses interbedded throughout the till. The entire drumlin field is subdivided into a series of sub-parallel regions separated by deep troughs that extend to depths as great as 850 m below the drumlin-capped upland surface. Regional relationships indicate that the drumlins and the troughs formed contemporaneously, but that both post-date the deposition of the outwash. Thus, drumlin formation (net subglacial deposition) beneath some portions of the Puget Lobe was accompanied by simultaneous selective linear erosion in adjacent regions. This intense erosion may have been due in part to excavation by concentrated subglacial water flow, in contrast to the minor effects of subglacial water beneath the drumlin-forming portions of the ice sheet. Such fluvially enhanced subglacial erosion would be consistent with previous estimates of high sliding velocity and resultant large volume of meltwater production for the short-lived Puget Lobe.
Graph Effective Resistance and Distributed Control: Spectral Properties and Applications

We introduce the concept of matrix-valued effective resistance for undirected matrix-weighted graphs. Effective resistances are defined to be the square blocks that appear in the diagonal of the inverse of the matrix-weighted Dirichlet graph Laplacian matrix. However, they can also be obtained from a "generalized" electrical network that is constructed from the graph, and for which currents, voltages and resistances take matrix values. Effective resistances play an important role in several problems related to distributed control and estimation. They appear in least-squares estimation problems in which one attempts to reconstruct global information from relative noisy measurements; as well as in motion control problems in which agents attempt to control their positions towards a desired formation, based on noisy local measurements. We show that in either of these problems, the effective resistances have a direct physical interpretation. We also show that effective resistances provide bounds on the spectrum of the graph Laplacian matrix and the Dirichlet graph Laplacian. These bounds can be used to characterize the stability and convergence rate of several distributed algorithms that appeared in the literature.
A Comparison of the Jones and Stead-Wells Spirometers

A comparison was made between the noncounterweighted Jones and Stead-Wells spirometers, and “conversion factors” were determined for the forced expiratory volume in one second (FEV 1 ) and the forced vital capacity (FVC). A cross-sectional study produced a high correlation between the instruments for these two measurements, yielding quadratic and linear regression equations (“conversion factors”) for FEV 1 and FVC, respectively. Standard deviations of measurements were similar for both spirometers. Results from a longitudinal study agreed with the “conversion factors” predicted from the cross-sectional study; however, significant day-to-day variability was observed by both spirometers. Neither spirometer met all of the technical recommendations proposed by the Committees on Environmental Health and Respiratory Physiology of the American College of Chest Physicians; however, the Stead-Wells water-sealed spirometer complied more often than the Jones waterless spirometer (Pulmonor). In addition, the open-circuit procedure used for the Jones spirometer required more coordination in the subject than did the closed-circuit procedure employed in this study for the Stead-Wells spirometer; however, with application of the “conversion factors,” both instruments, yield comparable data and prove adequate for spirometric studies.
Coherence in the excited states of multidimensional systems: Dimer and exciton dynamics in crystalline phenazine

Coherence in multidimensional excited systems was established using optical and zero-field magnetic resonance spectroscopy. High resolution phosphorescence microwave double resonance at the Larmor frequency of the excited phenazine dimer gave the dynamics of optical coherence while the magnetic resonance spectra at 1.6 K gave a coherence time which was shown to be at least 10^5 times that of the stochastic-markoffian limit and approximately 11000 of the radiative lifetime. These results indicate that the cross-chain interaction does not destroy the in-chain spin correlation.
Some determinants of papaverine-induced femoral artery pressure gradients

Abstract The accuracy and reliability of papaverine-induced central arterial to common femoral artery pressure gradients, frequently used to estimate the hemodynamic significance of aortoiliac stenosis, depend on a reproducible, between patient increase in resting common femoral artery blood flow because of the linear relationship between pressure gradient and flow. Blood flow variability and the effect of proximal and distal occlusive disease on femoral artery pressure gradient and flow were determined by three methods: intraoperative electromagnetic blood flow measurements, hemodynamic model analysis, and flow calculations using intraoperative segmental resistance measurements. The ratios of papaverine-induced hyperemic to resting common femoral artery blood flow were 2.80 ± 0.781 (mean ± 1 SD, n = 19) for occluded and 3.07 ± 0.819 (n = 13, P > 0.5) for open superficial femoral arteries, respectively, when the papaverine-induced central arterial to common femoral artery mean pressure gradient was 0.5) for superficial femoral occlusion and patency, respectively, when the central to femoral mean pressure gradient was ⩾ 10 mm Hg. Hemodynamic model analysis predicts that superficial femoral artery occlusion reduces the hyperemic to resting common femoral artery flow ratio from 2 to 1.8 and from 3 to 2.5. The mean values of segmental resistance measured intraoperatively in 17 additional limbs with and in 17 without superficial femoral occlusion predict a reduction in flow ratios from 2 to 1.75 and from 3 to 2.44 when the superficial femoral is occluded. Model analysis also predicts a mild effect of iliac stenosis on the flow ratios. These results indicate that the increase in common femoral artery blood flow with papaverine is variable (large SD) between patients but only mildly reduced by superficial femoral occlusion and proximal stenosis. Caution in interpretation of the hemodynamic significance of aortoiliac stenosis from mean common femoral artery pressure gradients in the 10 mm Hg range without blood flow measurement is suggested.
Formulation of multiphase mixture models for fragmenting flows

Abstract The formulation of multiphase mixture models of fragmentation is discussed. It is demonstrated that choices of constitutive equations play a critical role in creating the independence of large and small scale effects exhibited by some models appearing in the literature. A model of this kind is used to make closed form plug flow fragmentor predictions which could be useful in the investigation of size class convergence.
HP-67/97 and TI-59 programs to fit the normal and log-normal distribution functions by linear regression

Abstract Programs for the HP-67/97 and Ti-59 programmable calculators have been written to fit data to the normal and log-normal distribution functions using linear regression. Each program calculates the value of the error function, erf, and the inverse error function, erf −1 , in fitting the distribution functions. The erf is calculated using its series expansion. The erf −1 is calculated by successive approximations using generated values of the erf and the Newton-Raphson method in conjunction with an initial guessing function to accelerate convergence. The coefficient of determination is calculated in order to determine which distribution best fits the data. Both the mean and standard deviation of the distribution function can be determined from the linear regression; therefore the program is useful in several areas, such as settler design, tracer data analysis and particulate surface area determinations.
Strong consistency of a sieve estimator for the variance in nonlinear regression

Abstract A strongly consistent sequence of estimators of the variance of the disturbance term in a nonlinear regression model is given. This improves earlier results based on either equicontinuity or uniform convergence arguments.
Non-destructive diagnosis of relativistic electron beams using a short undulator

Abstract The performance of an FEL depends critically on the characteristics of the electron beam used to drive it. In the past it has been very difficult to measure the details of the transverse and longitudinal phase-space distributions of high-energy electron beams with the precision required to predict FEL performance. Furthermore, the available diagnostics were generally perturbative, and could not be used simultaneously with lasing. We investigate the potential use of a short undulator insertion device for non-destructive diagnosis of relativistic electron beams. Incoherent visible to near-infrared synchrotron radiation from a single magnet in the diagnostic undulator will be used to obtain information on beam position and transverse phase-space. Coherent off-axis undulator radiation in the millimeter to sub-millimeter range will be used to measure longitudinal phase-space characteristics of the beam. These two types of radiation can be analyzed simultaneously, while the FEL is lasing; thus giving a complete picture of relevant electron beam characteristics. In this paper we analyze the theoretical and practical design issues associated with such a diagnostic undulator.
Early results from NASA's assessment of satellite servicing

Following recommendations by the NRC, NASA's FY 2008 Authorization Act and the FY 2009 and 2010 Appropriations bills directed NASA to assess the use of the human spaceflight architecture to service existing/future observatory-class scientific spacecraft. This interest in satellite servicing, with astronauts and/or with robots, reflects the success that NASA achieved with the Shuttle program and HST on behalf of the astronomical community as well as the successful construction of ISS. This study, led by NASA GSFC, will last about a year, leading to a final report to NASA and Congress in autumn 2010. We will report on its status, results from our March satellite servicing workshop, and recent concepts for serviceable scientific missions.
A Systematic Approach for Solving Large-Scale Problems by Neural Network: Open Refrigerated Display Cases and Droplet Evaporation Problems

A systematic approach for solving a large-scale design problem is proposed. The method consists of building a multidimensional test case matrix connecting an output (scalar or vector) to an input vector. Every element of the input vector spans over its possible minimum and maximum values with one or more levels in between. The experimental and validated computational methods are combined to find the output as a function of all permutations of the input variables. The results are used to train a neural network program to perform the proper interpolation for any other expected scenario. The number of required experiments is obtained asymptotically by adding more data to the neural network training set and examining the error. The applicability and feasibility of this approach is shown in two different problems: first, predicting and minimizing the infiltration rate into an open refrigerated display case; and second, predicting the evaporation rate of sessile microdroplets on a nonpermeable surface.
Achaete-Scute Complex Homolog-1 Promotes DNA Repair in the Lung Carcinogenesis through Matrix Metalloproteinase-7 and O(6)-Methylguanine-DNA Methyltransferase

Lung cancer is the leading cause of cancer-related deaths in the world. Achaete-scute complex homolog-1 (Ascl1) is a member of the basic helix-loop-helix (bHLH) transcription factor family that has multiple functions in the normal and neoplastic lung such as the regulation of neuroendocrine differentiation, prevention of apoptosis and promotion of tumor–initiating cells. We now show that Ascl1 directly regulates matrix metalloproteinase-7 (MMP-7) and O(6)-methylguanine-DNA methyltransferase (MGMT). Loss- and gain-of-function experiments in human bronchial epithelial and lung carcinoma cell lines revealed that Ascl1, MMP-7 and MGMT are able to protect cells from the tobacco-specific nitrosamine NNK-induced DNA damage and the alkylating agent cisplatin-induced apoptosis. We also examined the role of Ascl1 in NNK-induced lung tumorigenesis in vivo. Using transgenic mice which constitutively expressed human Ascl1 in airway lining cells, we found that there was a delay in lung tumorigenesis. We conclude that Ascl1 potentially enhances DNA repair through activation of MMP-7 and MGMT which may impact lung carcinogenesis and chemoresistance. The study has uncovered a novel and unexpected function of Ascl1 which will contribute to better understanding of lung carcinogenesis and the broad implications of transcription factors in tobacco-related carcinogenesis.
Group treatment of combat nightmares in post-traumatic stress disorder

This paper outlines a method for detoxifying combat nightmares in a group treatment setting and illustrates the method in a three dream sequence. Aside from the initial trauma, there is no symptom of post-traumatic stress disorder (PTSD) more vivid, painful, humbling, and ego-shattering than the combat nightmare, which forces a reliving of horrifying events. When viewed as a direct road back to the trauma, the nightmare can be transformed into a powerful therapeutic tool if deciphered empathically in the company of combat veterans who, like the dreamer, have survived similar catastrophic events. Successful depotentiation of nightmares gives PTSD patients increased control and confidence in working through the aftereffects of trauma.
New cached-sufficient statistics algorithms for quickly answering statistical questions

This talk is about recent work on new ways to exploit preprocessed views of data tables for tractably solving big statistical queries. We'll describe deployments of these new algorithms in the realms of detecting killer asteroids and unnatural disease outbreaks.In recent years, several groups have looked at methods for pre-storing general sufficient statistics of the data in spatial data structures such as kd-trees and ball-trees so that both frequentist and Bayesian statistical operations become fast for large datasets. In this talk we will look at two other classes of optimization required in important statistical queries.The first involves iterating over all spatial regions (big and small). The second involves detection of tracks from noisy intermittent observations separated far apart in time and space. We will also discuss the implications that have arisen from making these operations tractable. We will focus particularly onDetecting all asteroids in the solar system larger than Pittsburgh's Cathedral of Learning (data to be collected over 2006-2010). Early detection of emerging diseases based on national monitoring of health-related transactions..