cssi/SciSciGPT-SciSciNet huggingface dataset:
Suprachiasmatic nucleus and photic entrainment of circannual rhythms in ground squirrels.

The efficacy of photoperiod as a zeitgeber for entrainment of circannual body weight and estrous rhythms was tested in female golden-mantled ground squirrels maintained for 3 or more years in either a simulated natural photoperiod (SNP) or a fixed LD 14:10 photoperiod (FP). The role of the retinohypothalamic tract—suprachiasmatic nucleus (RHT-SCN) projection in photic entrainment was assessed in animals that sustained destruction of the SCN (SCNx ). Circannual rhythms were lengthened by the SNP as compared to the FP. Mean periods (τ's) for neurologically intact animals in the third year of testing were 49.6 ± 0.3 weeks and 43.1 ± 1.2 weeks (p < 0.001) for the SNP and FP groups, respectively; furthermore, 56% and 7% of animals in these groups had τ's not significantly different from 365 days (p < 0.005), and within-group variability was lower for SNP than for FP squirrels (p < 0.01). SCNx squirrels differed from animals with the SCN intact (SCNc), as evidenced by higher within-group variability (p < 0.001)...
High Speed Equities Trading: 1993–2012

High speed trading has drawn the attention of regulators who fear that such trading harms markets and leads to excessive speculation.1 The Flash Crash of May 6, 2010 is taken as evidence of the potential harmful effects of high frequency trading. On the other hand, some view high frequency trading as a manifestation of technological advances that have reduced the optimal trade size and improved order routing. From that perspective, high speed trading is a continuation of a long-standing trend to more rapid and more efficient trading. This study shows that the speed of trading has changed dramatically. The average number of trades per day for large cap New York Stock Exchange stocks has risen from about 500 to more than 40 000 in the period 1993–2011. At the same time, the average trade size has fallen from 1600 shares to 200 shares. The ultimate sources of these changes are the technology that has automated almost all aspects of trading and the regulatory developments that have helped reduce bid-ask spreads and made markets more accessible. The result of these developments is that markets are considerably more liquid and less costly. High frequency traders draw on this liquidity and also contribute to it.
CD20 Antibody Primes B Lymphocytes for Type I Interferon Production

CD20 is a B cell surface marker that is expressed in various stages in B lymphocytes and certain lymphomas. Clinical administration of CD20 antibody, such as rituximab, is used widely to treat human B-cell lymphomas and other diseases. However, CD20 antibody failed to treat systemic lupus erythematosus (SLE or lupus). The reason for the failure is currently unknown. Type I interferons (IFN) are a major component for the host innate immunity, and a key pathogenic factor in lupus. We found that CD20 antibody potentiated human B cells for its production of IFNs in vitro. This function was specific to CD20-expressing cells and the potentiation function seems to be instant. In addition, ectopic expression of CD20 in non-B-lymphocytes increased the IFN promoter reporter activities. Because IFNs are a key pathogenic factor in lupus, our data suggest that, in the presence of virus infection, the CD20-antibody-mediated enhancement of IFN production might be related to its failure in lupus treatments. This work may provide new insights for CD20-Ab therapeutic applications.
Reoperation for carotid stenosis is as safe as primary carotid endarterectomy

Abstract Purpose: Patients with recurrent carotid artery stenosis are sometimes referred for carotid angioplasty and stenting because of reports that carotid reoperation has a higher complication rate than primary carotid endarterectomy. The purpose of this study was to determine whether a difference exists between outcomes of primary carotid endarterectomy and reoperative carotid surgery. Methods: Medical records were reviewed for all carotid operations performed from September 1993 through March 1998 by vascular surgery faculty at a single academic center. The results of primary carotid endarterectomy and operation for recurrent carotid stenosis were compared. Results: A total of 390 operations were performed on 352 patients. Indications for primary carotid endarterectomy (n = 350) were asymptomatic high-grade stenosis in 42% of the cases, amaurosis fugax and transient ischemic symptoms in 35%, global symptoms in 14%, and previous stroke in 9%. Indications for reoperative carotid surgery (n = 40) were symptomatic recurrent lesions in 50% of the cases and progressive high-grade asymptomatic stenoses in 50%. The results of primary carotid endarterectomy were no postoperative deaths, an overall stroke rate of 1.1% (three postoperative strokes, one preoperative stroke after angiography), and no permanent cranial nerve deficits. The results of operations for recurrent carotid stenosis were no postoperative deaths, no postoperative strokes, and no permanent cranial nerve deficits. In the primary carotid endarterectomy group, the mean hospital length of stay was 2.6 ± 1.1 days and the mean hospital cost was $9700. In the reoperative group, the mean length of stay was 2.6 ± 1.5 days and the mean cost was $13,700. The higher cost of redo surgery is accounted for by a higher preoperative cerebral angiography rate (90%) in redo cases as compared with primary endarterectomy (40%). Conclusion: In this series of 390 carotid operations, the procedure-related stroke/death rate was 0.8%. There were no differences between the stroke-death rates after primary carotid endarterectomy and operation for recurrent carotid stenosis. Operation for recurrent carotid stenosis is as safe and effective as primary carotid endarterectomy and should continue to be standard treatment. (J Vasc Surg 1999;30:26-35.)
Update on Neuromodulation

Neuromodulation has become an integral part of our treatment algorithm for overactive bladder symptoms refractory to conservative therapy and for nonobstructive urinary retention. Long-term outcomes are available for sacral neuromodulation and reflect high satisfaction rates and acceptable rates of revision and reoperation. Recent studies suggest that there also may be beneficial outcomes in patients with symptoms related to the bowels or with pelvic pain. Likewise, pediatric patients may also derive benefit from this type of therapy. Although other forms of neuromodulation have only recently emerged, there is already evidence to suggest that stimulation of the dorsal tibial, pudendal, and dorsal genital nerves may provide benefits in the aforementioned conditions. Although long-term outcomes and placebo-controlled studies are generally lacking, there are few adverse events, and therapy may be performed with minimal anesthetic requirements. Further cost-effectiveness analyses also will be helpful if these procedures are to be adopted into routine use.
The use of Cayley trees to study excitations in disordered solids

Abstract It is shown how, and why, Cayley trees (Bethe-lattices) are useful models for studying elementary excitations in disordered solids. Special attention is focused on the effects of disorder on the electronic states of various amorphous bonded solids. Specific examples are drawn from problems involving: (1) bond-angle distortions and localized states in amorphous Ge, (2) hydrogen configurations in hydrogenated amorphous Si, (3) bonding-coordination defects in amorphous As and (4) amorphous SiSiO2 interfaces.
Viviparous-1 Mutation in Maize Conditions Pleiotropic Enzyme Deficiencies in the Aleurone

The viviparous-1 (vp1) mutation in maize (Zea mays L.) conditions a unique pleiotropic phenotype: premature germination of the embryo and failure to synthesize anthocyanin (flavonoid) pigments in the aleurone. By using a B-A translocation, it is possible to analyze the basis for the anthocyaninless phenotype of vp1 in the absence of vivipary. Anthocyaninless vp1 aleurones were found to be deficient in at least three enzymes of flavonoid biosynthesis (phenylalanine ammonia lyase, chalcone synthase, and UDPG-flavonoid glucosyltransferase) as well as in several other metabolically unrelated enzymes that show pronounced increases in late stages of aleurone development. The set of structural genes encoding such enzymes is postulated to be under the regulation of the vpl gene.
Quantifying tropospheric volcanic emissions with AIRS : The 2002 eruption of Mt. Etna (Italy)

[1] The Atmospheric Infrared Sounder (AIRS) is a hyperspectral IR spectrometer orbiting on the EOS/Aqua spacecraft since May 2002. In late October 2002, AIRS detected lower tropospheric sulfur dioxide and ash emitted by an eruption of Mt. Etna (Italy), in plumes which could be tracked over 1000 km from the volcano into north Africa. We report retrievals of SO2 and ash column amounts and ash particle size in the Etna plumes. AIRS total SO2 compares favorably with contemporaneous ground-based correlation spectrometry (COSPEC) measurements. Retrieval of ash cloud parameters in the eruption plumes permits quantitative studies of distal ash fallout. The Etna data demonstrate the potential of AIRS to improve measurements of volcanic SO2 and ash loading in the troposphere, and to refine our understanding of volcanic cloud composition, structure and evolution.
Automatic system for brain MRI analysis using a novel combination of fuzzy rule-based and automatic clustering techniques

Analysis of magnetic resonance images (MRI) of the brain permits the identification and measurement of brain compartments. These compartments include normal subdivisions of brain tissue, such as gray matter, white matter and specific structures, and also include pathologic lesions associated with stroke or viral infection. A fuzzy system has been developed to analyze images of animal and human brain, segmenting the images into physiologically meaningful regions for display and measurement. This image segmentation system consists of two stages which include a fuzzy rule-based system and fuzzy c-means algorithm (FCM). The first stage of this system is a fuzzy rule-based system which classifies most pixels in MR images into several known classes and one `unclassified' group, which fails to fit the predetermined rules. In the second stage, this system uses the result of the first stage as initial estimates for the properties of the compartments and applies FCM to classify all the previously unclassified pixels. The initial prototypes are estimated by using the averages of the previously classified pixels. The combined processes constitute a fast, accurate and robust image segmentation system. This method can be applied to many clinical image segmentation problems. While the rule-based portion of the system allows specialized knowledge about the images to be incorporated, the FCM allows the resolution of ambiguities that result from noise and artifacts in the image data. The volumes and locations of the compartments can easily be measured and reported quantitatively once they are identified. It is easy to adapt this approach to new imaging problems, by introducing a new set of fuzzy rules and adjusting the number of expected compartments. However, for the purpose of building a practical fully automatic system, a rule learning mechanism may be necessary to improve the efficiency of modification of the fuzzy rules.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Comparative analytical studies of fatty acids of the algaChlorella pyrenoidosa

Gas-liquid chromatography, several versions of paper chromatography, and alkaline isomerization have been applied to one preparation ofChlorella fatty acid methyl esters. GLC outranks other methods in rapidity, reproducibility, and resolving power. The presence of nonvolatile components in the sample can lead to erroneous results. Among PC methods which might arise from autoxidation and polymerization are detected. Esters or acids with 14 or fewer C atoms should be analyzed as nonvolatile derivatives. AI, as used here, introduces a systematic error in the determination of linoleic and linolenic acids. The quantitative results of the methods are in agreement for the major components, which all belong to the C10 and C18 series. A number of minor components have been revealed by GLC and/or PC. They are tentatively identified as <C12, C12, four C14, C15, two C17, C19, three C20, two C22, and C24 acids. Several of these compounds have been found independently by different methods in hydrogenated form or as radioactive esters. This enhances the certainty of their identification. Eurichment by fractional distillation was essential for their detection. Possible losses in their distillation and other considerations make uncertain the assay of most of the minor components by GLC or PC.
Processing of eutectic Zn-5% Al alloy by equal-channel angular pressing

Abstract Multi-pass equal-channel angular pressing (ECAP) was applied to the eutectic Zn–5% Al alloy as a first step in the examination of the binary Zn–Al alloy system by using two different processing routes: route A, where the sample is pressed repetitively through the die without rotation, and route C, where the sample is rotated by 180° after each pass. A “three-block die” for ECAP was designed and manufactured. Evolution of hardness was investigated and microstructural changes were noted during ECAP. Variations in the applied load during ECAP of the alloy were analyzed, and the relationship between maximum load and hardness was discussed. It was observed that the equiaxed grain structure of the as-received alloy completely disappeared and instead a banded structure was formed during the ECAP process. Hardness of the alloy decreased with increasing number of passes for both processing routes. The applied load during ECAP increased up to a maximum value, and this was followed by a decrease until the end of pressing in all processing conditions. The maximum load required for the ECAP of the alloy decreased for both routes with increasing number of passes. It was observed that the hardness and the maximum load showed similar trends with number of passes for both processing routes.
Performance‐based seismic evaluation of the Icon Hotel in Dubai, United Arab Emirates

SUMMARY The Icon Hotel, which is part of the Dubai Promenade in Dubai, is a new waterfront development and represents cutting edge architecture. This building has a unique ‘donut shape’ with significant design and buildability challenges in the field of structural engineering. The wheel shape tower is 160 m high with an external diameter of 165 m, an internal diameter of 78 m and a depth of 35 m. It was designed to accommodate hotel and residential occupancies. The building's primary structural system is composed of two concrete core walls placed 96 m apart on either side and partially coupled by mega steel trusses at upper mechanical floor as well as long-span steel arches located at the top to accommodate the required shape of the building. This paper presents the structural engineering design approach used to evaluate the seismic behaviour of this building by implementing performance-based design methodology. The analysis results show that the building will behave in a desired manner during future anticipated earthquakes. Copyright © 2010 John Wiley & Sons, Ltd.
PHOTOSYNTHETIC RATE AND MESOPHYLL SURFACE AREA IN EXPANDING LEAVES OF ALTERNANTHERA PHILOXEROIDES GROWN AT TWO LIGHT LEVELS

Leaves of Alternanthera philoxeroides, alligator weed, developed at a photosynthetic photon flux density (PPFD, light energy at wavelengths of 400 to 700 nm) of 790 ,umol sec-' m-2 (High Light) had less surface area, were thicker, had a higher maximum Pn (net rate of CO2 uptake), and required a higher PPFD for saturation of PnX than leaves developed at 160 ,umol sec-' m-2 (Low Light). Mesophyll thickness at Low Light was within 19% of maximum 2 days after emergence but at High Light, thickness increased 79% between 2 and 16 days after leafemergence. The ratio of mesophyll surface area to leaf surface area decreased during development in both light treatments; the ratio, however, was over 70% greater in fully expanded High Light leaves than in Low Light leaves. Maximum Pn expressed on a leaf surface area basis was 158% greater in High Light leaves than in Low Light leaves, but Pn was only 58% greater when expressed on a mesophyll surface area basis. It was estimated that fully expanded High Light leaves fixed 72% more CO2 per leaf (Pn expressed per unit surface area times the total surface area per leaf) than fully expanded Low Light leaves when Pn was measured at the PPFD leaves expanded under. Both High and Low Light leaves would fix about the same amount of CO2 per leaf when Pn was measured at 160 ,umol sec-' m-2 because the larger surface area of the Low Light leaves offset small differences in Pn
The file drawer problem and tolerance for null results

For any given research area, one cannot tell how many studies have been conducted but never reported. The extreme view of the "file drawer problem" is that journals are filled with the 5% of the studies that show Type I errors, while the file drawers are filled with the 95% of the studies that show nonsignificant results. Quantitative procedures for computing the tolerance for filed and future null results are reported and illustrated, and the implications are discussed. (15 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Inducible expression of B7-H1 (PD-L1) and its selective role in tumor site immune modulation

Immune evasion is an important hallmark of cancer, and a better understanding of this mechanism is essential for the development of effective strategies against cancer. The B7 homolog 1 (B7-H1)/programmed cell death 1 (PD-1) pathway has been demonstrated as a major mechanism of immune evasion in tumor site, and its blockade therapy shows very encouraging results in clinical trials. Inducible B7-H1 expression in tumor microenvironment is complex, with multidimensional interactions and expression by different subsets of hematopoietic and nonhematopoietic cells. Understanding these interactions and how tumors take advantage of this pathway can help us design future strategies for better therapeutic efficacy and to overcome resistances.
EFFECT OF HEAT AND MASS TRANSFER COEFFICIENTS ON THE PERFORMANCE OF AUTOMOTIVE CATALYTIC CONVERTERS

AbstractThis paper numerically investigates the role of heat and mass transfer coefficients on the performance of automotive catalytic converters, which are employed to reduce engine exhaust emissions. The pollutant conversion performance of a converter is influenced by a number of physical and chemical processes that take place in gaseous and solid phases as the exhaust gases flow through the catalyst. A quantitative predictive understanding of these complex catalyst processes involving flow dynamics, heterogeneous surface reactions and heat and mass transport mechanisms is important in improving the converter design. The role of convective transport phenomena becomes important at high temperature when the mass transfer becomes rate-limiting to an increasing extent. The objective of the present study is to elucidate the influence of convective heat and mass transfer coefficients (mechanisms). The mathematical model considers the conservation of mass, momentum and energy in both gaseous and solid phases. ...
Measurement of the Distribution of Site Enhancements in Surface-Enhanced Raman Scattering

On nanotextured noble-metal surfaces, surface-enhanced Raman scattering (SERS) is observed, where Raman scattering is enhanced by a factor, G, that is frequently about one million, but underlying the factor G is a broad distribution of local enhancement factors, eta. We have measured this distribution for benzenethiolate molecules on a 330-nanometer silver-coated nanosphere lattice using incident light of wavelength 532 nanometers. A series of laser pulses with increasing electric fields burned away molecules at sites with progressively decreasing electromagnetic enhancement factors. The enhancement distribution P(eta)deta was found to be a power law proportional to (eta)(-1.75), with minimum and maximum values of 2.8 x 10(4) and 4.1 x 10(10), respectively. The hottest sites (eta >10(9)) account for just 63 in 1,000,000 of the total but contribute 24% to the overall SERS intensity.
Biliopancreatic Limb Obstruction in Gastric Bypass at or Proximal to the Jejunojejunostomy: A Potentially Deadly, Catastrophic Event.

Background: Although unusual, but not rare, obstruction in the vicinity of the jejunojejunostomy in Roux-Y gastric bypass (RYGBP) can progress in a very short period of time to a life-threatening situation. Methods: Over a 10-year period in 1,174 RYGBP's, we have seen seven instances of acute and subacute partial to complete small bowel obstructions in the vicinity of the jejunojejunostomy, which can lead to acute gastric dilatation due to obstruction of the bilio-pancreatic limb. Signs and symptoms of the obstruction may include tachycardia, oliguria, hypotension, severe epigastric pain with or without a palpable mass in the epigastrium, chronic bile regurgitation and bilious vomiting, and a possible increase in serum amylase. Laboratory data otherwise has not been helpful, and although a palpable abdominal mass may be diagnostic, the best tools have been radiologic, i.e. the acute abdomen series, limited upper GI series in the patients that appear to be only partially obstructed, abdominal ultrasound and probably most importantly, CT of the abdomen. Results: In the seven cases presented, diagnoses included internal hernia, adhesions, an idiopathic spontaneous hematoma of the bowel wall and retrograde intussusception at the jejunojejunostomy. Conclusions: Since many surgeons who perform bariatric surgery are alone in their community, they should train their non-bariatric surgical colleagues and associates to be aware of these potential deadly problems.
Upper Extremity Nerve Entrapments

Nerve entrapment occurs when a nerve is "trapped" by pathologic changes in the tissues through which the nerve passes. Nerve entrapments occur more frequently in the upper than in the lower extremities and are characterized by pain and paresthesias, with or without sensory and/or motor nerve loss. The major pathologies related to upper extremity nerve entrapment involving the cervical, thoracic, shoulder, elbow, and wrist areas are discussed in this article.
Allograft TNFβ and IL16 polymorphisms influence HCV recurrence and severity after liver transplantation

Hepatitis C (HCV) recurrence after liver transplantation is universal although severity varies. We explored whether certain donor cytokine gene polymorphisms may be useful markers of susceptibility to severe recurrence. Allograft tumor necrosis factor (TNF) beta and interleukin (IL) 16 gene polymorphisms were correlated with l-yr clinical outcome among HCV+ recipients. Recipients of donor TNFbeta(2,2) (n = 8) experienced less recurrence (50% vs. 71%, P < 0.05), less fibrosis (25% vs. 76%, P < 0.01), and less rejection (25% vs. 71%, P < 0.01) than donor TNFbeta(1,1) (n = 19). Recipients of donor TNFbeta(1,2) (n = 27) demonstrated an intermediate picture with less fibrosis (56%, P < 0.01) and less rejection (37%, P < 0.01) than TNFbeta(1,1). Recipients with donor IL16(TC) (n = 22) showed less recurrence (65% vs. 78%, P = 0.05), less fibrosis (53% vs. 67%, P = 0.06), and less rejection (41% vs. 55%, P = 0.06) than IL16(TT) (n = 32) genotype. Recipients of the combination TNFbeta(2,2)/IL16(TC) donor genotype had the most benign clinical outcome with less recurrence (33% vs. 75%, P < 0.01), no fibrosis (0% vs. 50%, P < 0.001), and fewer rejections (33% vs. 75%, P < 0.01) than donor TNFbeta(1,1)/IL16(TT) genotype. In vitro production of cytokines correlated with genotype. Release of soluble TNFbeta for TNFbeta(1,1) vs. TNFbeta(1,2) and TNFbeta(2,2) was 4803 +/- 2142 pg/mL vs. 5629 +/- 3106 (P = not significant [ns]) and 7180 +/- 3005 (P = ns). Release of soluble IL16 for IL16(TT) vs. IL16(TC) was 437 +/- 86 pg/mL vs. 554 +/- 39 (P = 0.06). In conclusion, allograft TNFbeta and IL16 gene polymorphisms may be useful markers to predict the severity of disease recurrence among HCV+ patients after liver transplantation.
Electron-beam lithography: directions in direct write and mask making

Two major categories of electron beam lithography systems have been developed over the course of many years: Direct write of chips on silicon, and patterning of optical masks on quartz and glass substrates. This paper addresses this dual role and what it implies for the different classes of electron beam lithography tools. In direct write, with dimensions at and below 0.25 m, tool resolution, accuracy in registration and overlay, process integration, and other factors are of critical importance. Most recent advances in this area will be described. Current work on device fabrication below 0.25 ,um demonstrates the capability to integrate all sectors of electron beam lithography to provide early research work for ULSI device technology demonstration. These dimensions are necessary for the fabrication of 256 MB DRAM chips, for example. For mask making it is widely ackowledged that much of the learning from direct write electron beam lithography tools becomes applicable to mask patterning as well. However, more stringent requirements are burdened in particular on x - y stage accuracy and long term overall systems stability.
Solving microstructure electrostatistics with MIMD parallel supercomputers and Split-C

Abstract We consider parallel computational algorithms for the boundary integral solutions of the Laplace equation for use in the simulation of electrorheological fluids and as a model study of a class of elliptic partial differential equations that appear in basic microscopic descriptions of heterogeneous structured continua. The viewpoint is that of constructing large scale simulations that bridge micro- and macro-length and time scales on state-of-the-art parallel supercomputers. Because of long range interactions, fast communications are the key to scalable N -Body algorithms. The communication scheduling strategies of Fuentes and Kim are examined in two contexts on the Thinking Machines CM-5 parallel computer. First, an N -Body simulation implementation in C using the standard send-receive message passing primitives in the CMMD 2.0 library shows that communication scheduling leads to dramatic improvements in computational performance. Second, an implementation in Split-C, which uses highly efficient active messages to implement shared memory communication, reduces communication overhead by an order of magnitude. Taken together, these two developments portend great promise for the development of efficient large scale simulations using portable, high level parallel programming languages.
Temperature acclimation effects on monkey liver ribo- and deoxyribonucleic acid and on ribonucleic acid of other organs.

SummaryStudies were made to determine the influence of cold and heat acclimation on the RNA content of the heart, liver, pancreas, kidneys, and cerebral hemispheres in the squirrel monkey (Saimiri sciurea). Total DNA was assayed, and liver RNA: DNA ratios were calculated. The total amounts of RNA in the kidneys, heart, and pancreas were increased as a consequence of cold acclimation: in the kidneys and heart proportionally to the increase per g protein, but in the pancreas—the organ which showed greatest change in RNA content—there was an increase in RNA per g protein. Since greater amounts of food are consumed in the cold, necessitating enhanced insulin and digestive enzyme secretions, the outflow of these proteins probably prevents a percentage protein accumulation in the pancreas equal to that of RNA. Cold exposure produced a significant increase in total DNA and total protein in the liver which may be due to hepatic cell proliferation. However, there was no increase in total liver RNA which, among oth...
Optically detected ESR studies of recombination processes in a-Si:H

Abstract A study of recombination processes in high-quality (intrinsic) and light-soaked hydrogenated amorphous silicon (a-Si:H) using the technique of optically detected electron spin resonance (ODESR) is reported. A time-domain detection scheme is employed, instead of the conventional lock-in technique, to record the ODESR lineshapes, which effectively minimizes the well-known interference between the ‘enhancing’ and ‘quenching’ signals. Monitoring the photoluminescence (PL), below 1.1 eV, in the intrinsic sample, a nearly symmetric enhancing signal (g = 2.008) related to radiative recombination of spin pairs in shallow band-tail states and an asymmetric quenching signal (g = 2.005) related non-radiative recombination of spin pairs in deep band tail states are observed. A quenching signal at half-field ( g ≌ 4 ) is also observed. The light-soaked sample exhibits an additional signal (g = 2.006) which is related to the dangling bonds. The PL excitation energy, Ex, is varied from above to below the optical gap to study possible changes in the recombination processes. It is found that the ODESR lineshapes are essentially the same for Ex > 1.5 eV and some subtle changes occur for Ex
Diffusive dynamics of nanoparticles in aqueous dispersions

The diffusive dynamics of 100 nm to 400 nm diameter polystyrene nanoparticles dispersed in water were studied using brightfield and fluorescence based differential dynamic microscopy (DDM) and compared to those obtained from dynamic light scattering. The relaxation times measured with brightfield and fluorescence DDM over a broad range of concentration of nanoparticles (10−6 ≤ φ ≤ 10−3) and scattering vectors (0.5 μm−1 < q < 10 μm−1) are in excellent agreement with each other and extrapolate quantitatively to those obtained from DLS measurements. The diffusion coefficients extracted from the q-dependent relaxation times using all three methods are independent of the nanoparticle concentration.
Terminal RNA uridylyltransferases of trypanosomes.

Abstract Terminal RNA uridylyltransferases (TUTases) are functionally and structurally diverse nucleotidyl transferases that catalyze template-independent 3′ uridylylation of RNAs. Within the DNA polymerase β-type superfamily, TUTases are closely related to non-canonical poly(A) polymerases. Studies of U-insertion/deletion RNA editing in mitochondria of trypanosomatids identified the first TUTase proteins and their cellular functions: post-transcriptional uridylylation of guide RNAs by R NA e diting T UTase 1 (RET1) and U-insertion mRNA editing by R NA e diting T UTase 2 (RET2). The editing TUTases possess conserved catalytic and nucleotide base recognition domains, yet differ in quaternary structure, substrate specificity and processivity. The cytosolic TUTases TUT3 and TUT4 have also been identified in trypanosomes but their biological roles remain to be established. Structural analyses have revealed a mechanism of cognate nucleoside triphosphate selection by TUTases, which includes protein–UTP contacts as well as contribution of the RNA substrate. This review focuses on biological functions and structures of trypanosomal TUTases.
The effect of estradiol on hormonally stimulable adenylyl cyclase activity and on progesterone production in normal and regressing corpora lutea from control and human chorionic gonadotropin-treated pseudopregnant rabbits.

The effect of administering a luteolytic dose of hCG (100 IU, iv) to 9-day pseudopregnant rabbits that received either no other treatment (controls) or one of two estradiol (E-1.5 or E-15) treatments was studied. E-1.5 and E-15 consisted of 1.5 μg estradiol (E) every 12 h and 15 μg E every 12 h, respectively; these treatments were administered sc in sesame seed oil starting at 2200 h on day 8 and continued through 2200 h on day 11. Animals were bled daily from days 9–12 and sacrificed between 1000–1100 h on day 12, at which time serum and corpora lutea (CL) progesterone content, weight, and adenylyl cyclase activities stimulated by LH (10 μg/ml) and isoproterenol (Iso; 10−4m) were determined. We found that 1) neither low (E-1.5) nor high (E-15) E treatment prevented functional luteolysis (drop in serum progesterone) induced by hCG; 2) E-15 but not E-1.5 prevented structural luteolysis (CL weight loss) induced by hCG; 3) E-15 but not E-1.5 resulted in CL progesterone levels that, after hCG, were indistingu...
Axonal guidance of developing optic nerves in the frog. II. electrophysiological studies of the projection from transplanted eye primordia.

When a primordial eye was transplanted to the ear position in Rana pipiens embryos, the optic nerve from the ectopic eye penetrated the medulla and invariably established a tract in the dorsolateral white matter of the ipsilateral spinal cord. In response to visual stimulation of the transplanted eye, extracellular recordings with metal microelectrodes were conducted within the spinal cords of post-metamorphic animals. Visual activity in the spinal cord could only be recorded in those experimental animals in which the transplanted optic nerve succeeded in penetrating the medulla. This activity was frequently encountered in the gray matter of the cord well below the dorsolateral position of the transplanted optic tract. The discharge characteristics and adaptation properties of the visual activity were often similar to that of optic nerve fibers from normal eyes suggesting that axons or their collaterals branch off from the transplanted optic tract and arborize within the spinal cord. However, occassionally stimulation of the transplanted eye evoked activity with adaptation and/or response characteristics unlike that of normal optic nerve fibers. Visual activity in the spinal cords of our experimental animals could be driven by moving small dark objects within circumscribed regions in the visual field of the transplanted eye. However we were unable to find any evidence of a systematic mapping of the transplanted retina within these abnormally penetrated spinal cords.
Colon vs small bowel rejection after total bowel transplantation in a pig model

With the advent of FK506, small bowel transplantation has become clinically feasible. Both clinically and experimentally, jejunal and ileal biopsies are used for early diagnosis of rejection. More recently, the colon, in addition to the small bowel, has been transplanted to decrease the high incidence of diarrhea after small bowel transplantation. A Bishop-Koop ileostomy allows biopsies on a regular basis, but the diagnosis of rejection remains a problem after takedown of the ileostomy. Rejection of the ileum is more frequent and more severe than rejection of the jejunum or the colon. Colon biopsy after ileostomy takedown would not rule out rejection of the ileum.
WE‐D‐9A‐01: A Novel Mesh‐Based Deformable Surface‐Contour Registration

Purpose: Initial guess is vital for 3D-2D deformable image registration (DIR) while dealing with large deformations for adaptive radiation therapy. A fast procedure has been developed to deform body surface to match 2D body contour on projections. This surface-contour DIR will provide an initial deformation for further complete 3D DIR or image reconstruction. Methods: Both planning CT images and come-beam CT (CBCT) projections are preprocessed to create 0–1 binary mask. Then the body surface and CBCT projection body contours are extracted by Canny edge detector. A finite element modeling system was developed to automatically generate adaptive meshes based on the image surface. After that, the projections of the CT surface voxels are computed and compared with corresponding 2D projection contours from CBCT scans. As a result, the displacement vector field (DVF) on mesh vertices around the surface was optimized iteratively until the shortest Euclidean distance between the pixels on the projections of the deformed CT surface and the corresponding CBCT projection contour is minimized. With the help of the tetrahedral meshes, we can smoothly diffuse the deformation from the surface into the interior of the volume. Finally, the deformed CT images are obtained by the optimal DVF applied on themore » original planning CT images. Results: The accuracy of the surface-contour registration is evaluated by 3D normalized cross correlation increased from 0.9176 to 0.9957 (sphere-ellipsoid phantom) and from 0.7627 to 0.7919 (H and N cancer patient data). Under the GPU-based implementation, our surface-contour-guided method on H and N cancer patient data takes 8 seconds/iteration, about 7.5 times faster than direct 3D method (60 seconds/iteration), and it needs fewer optimization iterations (30 iterations vs 50 iterations). Conclusion: The proposed surface-contour DIR method can substantially improve both the accuracy and the speed of reconstructing volumetric images, which is helpful for applying in adaptive radiotherapy. This research is supported by CPRIT individual investigator award RP110329.« less
Russia's Unfinished Revolution: Political Change from Gorbachev to Putin. By Michael McFaul. Ithaca, NY: Cornell University Press, 2001. 384p. $35.00. The Russian Parliament: Institutional Evolution in a Transitional Regime, 1989–1999. By Thomas F. Remington. New Haven: Yale University Press, 2001. 288p. $40.00.

Each of these books is, in its own way, a tour de force; each provides the best book-length account and analysis available to date on its subject. Michael McFaul's book offers a major contribution to thinking on regime change in general, as well as a fine account and analysis of Russia's transition from Sovietism. Thomas Remington's book, which investigates the nascence and internal operation of the Russian legislature, powerfully advances our understanding of the Russian parliament and the formation of political institutions more generally. Both books are scholarly and sophisticated, but each is also elegantly written, well organized, and accessible to the nonspecialist. Both authors were present at the creation of the new Russian political order, and each book is deeply informed by extensive interviews and first-hand observation.
Substance P activation of enteric neurons in response to intraluminal Clostridium difficile toxin A in the rat ileum

Abstract BACKGROUND & AIMS: Nerves have been suggested to mediate the effects of bacterial toxins in intestinal diseases. However, the mechanisms involved are unknown. This study examined endogenous substance P (SP) activation of the substance P receptor (SPR) on enteric neurons in the rat ileum after exposure to intraluminal Clostridium difficile toxin A. METHODS: After intraluminal injection of toxin A in ileal loops, tissue was examined for pathological changes by histology and for SPR activation by immunocytochemical analysis of SP-induced SPR endocytosis. RESULTS: After toxin A administration, > 70% of enteric neurons showed SPR endocytosis and became swollen with thickened dendrites. In contrast, SPRs in control rats were largely confined to the plasma membrane. Rats denervated of primary afferent fibers with neonatal capsaicin injection and animals pretreated with a nonpeptide SPR antagonist showed few endosomal SPRs, and the pathological inflammatory effects of toxin A were ablated. CONCLUSIONS: Intraluminal toxin A causes the release of SP from primary afferent neurons: this endogenous SP then acts on enteric neurons in the submucosal and myenteric plexuses. SP is the primary mediator of an axon reflex mediating neurogenic inflammation in the intestine. SPR blockade may prove to be a novel therapy used to prevent intestinal inflammation. (Gastroenterology 1996 Nov;111(5):1272-80)
Anisotropic ultrasound propagation in a smectic-A liquid crystal

Anisotropic ultrasound propagation was studied in a magnetically aligned monodomain smectic-$A$ liquid crystal (di-$n$-decyl azoxy methyl cinnamate). A large attenuation was observed near the isotropic-smectic-$A$ phase transition. The anisotropy in the sound velocity was found to be in agreement with the predictions of hydrodynamic theory, and no dispersion was found in the frequency range used (4-12 MHz). The temperature dependence of the physically meaningful elastic constants was determined. The anisotropy in the attenuation was also measured. Unlike the velocity anisotropy, no intermediate minimum was observed.
Drain use after open cholecystectomy: is there a justification?

Despite randomized trials showing no benefit, drain use after open cholecystectomy continues, perhaps as a result of more complicated patient presentation. We examined the reasons for drain use in patients undergoing open cholecystectomy and evaluated the effect of drain placement on surgical outcomes. Univariate and multivariate analyses compared pre- and intraoperative factors associated with drain placement, and postoperative outcomes in patients undergoing open cholecystectomy at our institution between 2002 and 2007. In 160 patients who underwent open cholecystectomy as primary operative procedure, 92 patients (58%) had a drain placed. In 22% of the cases, the surgeon’s stated reason for drain placement was hemorrhage, abscess, non-identification of critical structures, bile spillage, or concern for a bile leak. No reason was provided in78% of the operative reports. Multivariate analysis revealed diagnoses of acute, chronic, or gangrenous cholecystitis (n = 120, 75%), intraoperative bile spillage (n = 60, 38%), and higher than median intraoperative blood loss (>200 ml) as independent predictors of drain use (all p ≤ 0.042). Patients with drains had increased length of hospital stay, postoperative ICU admissions, rates of hospital re-admission, and use of post-operative endoscopy (all p ≤ 0.04). Patients with and without drains had similar rates of postoperative percutaneous drainage, bile leaks, intra-abdominal abscesses, wound infections, and deaths (all p ≥ 0.121). The use of drains after open cholecystectomy was associated with complicated patient presentations: cholecystitis, intraoperative bile spillage, and high intraoperative blood loss. These patients had longer and more complicated postoperative course and more re-admissions. However, use of intraoperative drains was not associated with a reduction in the need for postoperative percutaneous drainage or in improvement in the rates of bile leaks, infections, or deaths.
Bromocriptine and psychosis: A literature review

Bromocriptine is an ergot-derived dopamine agonist. Its current uses include the treatment of Parkinson's disease, postpartum ablaction, prolactionmas, acromegaly, and amenorrhea and galactorrhea secondary to neuroleptic use. It is often reported to produce psychiatric side effects such as confusion, hallucinations, and delusions. The literature is reviewed and supports a strong anecdotal relationship between bromocriptine use and psychosis.
Tissue binding of 2-acetylaminofluorene in BALB/c and C57B1/6 mice during chronic oral administration

Blood and tissue binding levels of [9-14C]2-acetylaminofluorene ([9-14C]2-AAF) administered in the diets of female BALB/c and C57Bl/6 mice, were determined. Blood and liver levels reached a plateau after 2--4 weeks, while levels in bladder tissue continued to increase. Binding levels two weeks administration were determined in liver, bladder, kidney, lung, spleen, heart and skeletal muscle. In every instance the binding was linear over a dose range of 0.5--500 ppm 2-AAF. Removal of the 2-AAF in the diet after 48 weeks resulted in a rapid loss of radioactivity from blood and liver, with little or no loss from bladder tissue. The linear dose-response relationship of tissue binding correlated well with the previously reported linear dose response curve for liver tumors but did not correlated with the reported non-linear dose response curve for bladder tumors. A reversed correlation was found in the ability of the tissue to remove bound fluorene residues and the observed rate of tumor occurrence following discontinued administration of the carcinogen.
A note on solution concepts for nontransferable utility games

Abstract While many game-theoretic solution concepts pertain to conditions of transferable utility (TU), market transactions and other exchanges generally occur under nontransferable utility (NTU). Extant solutions translate TU solution concepts to the NTU case by utilizing endogenously determined utility weight vectors, which can violate notions of equity. A new solution procedure is developed that resolves this longstanding problem, and an existence proof is provided.
Introduction to Innovations in System and Software Engineering

The National Aeronautics and Space Administration (NASA) was established on 1st October 1958, with the goal of furthering man’s understanding of the universe. Since then, NASA has found its way into space to make key discoveries and, although an agency of the United States government, has won the hearts of peoples around the world. The entire world delights in NASA’s successes, such as putting man on the moon or the more recent rovers on the surface of Mars; the world is disappointed in its failures, and mourns its tragedies. For nearly half a century, NASA technology has not only improved its ability to explore the frontiers of space, it has also found valuable applications in the everyday lives of people on Earth, ranging from invaluable solar heaters for rural communities to the most advanced forms of satellite communications in use today. NASA sets itself high goals for exploration and scientific data collection and analysis, all of which feeds back to give a greater understanding of the universe and improve human life. Almost everything that NASA does relies heavily on continuing innovations in systems and software engineering. During its lifetime, NASA has seen both hardware and software failures, resulting in necessary changes to missions, failure to achieve the scientific goals of missions, or even loss of a spacecraft. However, the advances made have enabled more forward-reaching goals that have resulted in more valuable insights that today govern our understanding of Earth’s place in the universe. Through innovations in systems and software engineering, the engineering process has become more predictable and measurable, resulting in fewer errors that can endanger missions and precious life. These innovations have enabled mankind to reach further into space for new scientific discoveries that provide the basis for improvement of the human condition.
Long-term performance of rival banks around bank failures

This paper examines the impact of bank failures on the long-term performance of rival banks. We find that bank failures are associated with changes in long-term performance at rival banks. However, the change in performance is not the same for all banks. Specifically, if the bank failure is a result of a problem that is unique to the failing bank, rival bank performance increases after the failure. However, if the bank failure is due to a general economic decline, rival bank performance decreases after the bank failure. Other differences between the two subgroups are also identified.
Explaining multi‐channel consumer's channel‐migration intention using theory of reasoned action

Purpose – The purpose of this paper is to examine how attitudes and subjective norms predict channel migration across the three channels based on the theory of reasoned action (TRA).Design/methodology/approach – A self‐administered questionnaire was administered to the participants comprised of staff, faculty, and students from four different universities in the southern and midwestern USA. The survey instrument was administered online and a total of 503 completed surveys were obtained.Findings – TRA was successful in predicting channel‐migration intention in brick‐and‐mortar stores, catalogues, and the internet. Utilitarian beliefs were more relevant in predicting attitude toward channel migration for all three channels. Normative beliefs for bricks‐and‐mortar stores and catalogues were significant in predicting subjective norms, the relationship was negative. Attitude and subjective norms were the predictors of the channel‐migration intention for all three channels.Research limitations/implications – Th...