cssi/SciSciGPT-SciSciNet huggingface dataset:
Evidence for multiple bonding in four-coordinate, cationic, platinumthiosilylenes via AIM and CDA; effects of phosphine choice

Abstract Hybrid DFT/HF calculations were performed on five complexes (PH 3 ) 2 (H)PtSi(SH) 2 + , (PH 3 ) 2 (H)PtSi(SMe) 2 + , (PMe 3 ) 2 (H)PtSi(SMe) 2 + , (P i Pr 3 ) 2 (H)PtSi(SEt) 2 + , and (PCy 3 ) 2 (H)PtSi(SEt) 2 + , and analyzed using CDA and Atoms-In-Molecules. Complexes were found to possess both SiS and SiPt multiple bond character, in contrast to earlier results at lower levels of theory. The origins of twisted geometries were determined to be primarily steric in nature. Increasing the size of aliphatic substituents on the phosphines leads to a more balanced bonding motif, but increases steric repulsion, while changing the substituent at silicon from hydrogen to methyl resulted in a lengthening of the SiPt bond. Based on these results, the use of PH 3 to substitute for PMe 3 and larger groups in calculations is discouraged, though methyl is an acceptable, if not electronically identical, substitute for larger aliphatic phosphines.
Epidermoid cyst: a rare intratesticular tumor in children

An 18-year-old boy presented with a palpable left testicular mass. Sonography demonstrated a circumscribed left intratesticular mass with concentric layers of alternating increased and decreased echogenicity (Fig. 1). There was no blood flow within the lesion with color Doppler interrogation (Fig. 2). Sonographic findings suggested a testicular epidermoid cyst, a diagnosis that was pathologically confirmed following surgical enucleation. Epidermoid cysts are rare benign tumors with no malignant potential that compose 1–2% of intratesticular masses in children [1]. Histopathologically, these lesions are lined by stratified squamous epithelium and filled with
Skeletal muscle changes associated with equine myotonic dystrophy

A progressive neuromuscular disorder in young horses, clinically apparent as early as 1 month of age, is characterized by generalized myotonia, muscle stiffness, muscle weakness and atrophy. Myotonia is identified by percussion dimpling and myotonic EMG discharges. Changes in one case included testicular hypoplasia, cataract formation, and glucose intolerance, indicating a systemic involvement. Pathologic changes in skeletal muscles from three affected foals were examined. Sarcoplasmic masses, ringed fibers, internal positioning of sarcolemmal nuclei, and nuclear rowing were among the primary histologic changes noted. Variation in fiber diameter size, especially atrophy, and type I predominance were also prominent changes. A neurogenic involvement was indicated by type grouping changes in several muscles.
Inclusion of flexibility benefits in discounted cash flow analyses for investment evaluation: A simulation/optimization model

Abstract It has been argued that conventional discounted cash flow (DCF) techniques, which are commonly used for investment justification, are inadequate and may even be inappropriate for the justification of advanced manufacturing systems whose strategic value comes from such attributes as flexibility. The problem lies in the proper estimation of the value of flexibility in financial or cash flow terms, so that the DCF techniques, which are otherwise conceptually sound, become relevant. This involves an assessment of the value of the flexibility of the manufacturing system in dealing with the uncertainties in its operating environment. We propose a simulation-optimization methodology for this assessment in cash flow terms and use it in a DCF framework. We use simulation to generate the environmental parameters in each period of an appropriate evaluation horizon. We develop a mathematical programming model to determine the distribution of the possible net revenues of the system in each period by capturing the combined effect of the different types of flexibilities that the manufacturing system may possess. We illustrate the application of our methodology using numerical examples and discuss how it can be used to assess the value of flexibility in cash flow terms. We show that our approach facilitates the justification of capital investment in advanced manufacturing systems which tend to get undervalued under the traditional DCF approaches. It would also help managers address such important questions as “how much incremental investment should we be willing to make now for the additional flexibility features?” and “does the expected present value of the future benefits of added flexibility justify the incremental capital investment now?” In essence, our paper addresses the question as to appropriate techniques or approaches for justifying proposed strategic investment decisions.
Test of a theoretical equation of state for elemental solids and liquids

We propose a means for constructing highly accurate equations of state (EOS) for elemental solids and liquids essentially from first principles, based upon a particular decomposition of the underlying condensed matter Hamiltonian for the nuclei and electrons. We also point out that at low pressures the neglect of anharmonic and electron-phonon terms, both contained in this formalism, results in errors of less than 5% in the thermal parts of the thermodynamic functions. Then we explicitly display the forms of the remaining terms in the EOS, commenting on the use of experiment and electronic structure theory to evaluate them. We also construct an EOS for aluminum and compare the resulting Hugoniot curve with data up to 5 Mbar, both to illustrate our method and to see whether the approximation of neglecting anharmonicity etc. remains viable to such high pressures. We find a level of agreement with experiment that is consistent with the low-pressure results.
The Mathematical Development of Set Theory from Cantor to Cohen

Set theory is an autonomous and sophisticated field of mathematics, enormously successful not only at its continuing development of its historical heritage but also at analyzing mathematical propositions cast in set-theoretic terms and gauging their consistency strength. But set theory is also distinguished by having begun intertwined with pronounced metaphysical attitudes, and these have even been regarded as crucial by some of its great developers. This has encouraged the exaggeration of crises in foundations and of metaphysical doctrines in general. However, set theory has proceeded in the opposite direction, from a web of intensions to a theory of extension par excellence, and like other fields of mathematics its vitality and progress have depended on a steadily growing core of mathematical structures and methods, problems and results. There is also the stronger contention that from the beginning set theory actually developed through a progression of mathematical moves, whatever and sometimes in spite of what has been claimed on its behalf. What follows is an account of the development of set theory from its beginnings through the creation of forcing based on these contentions, with an avowedly Whiggish emphasis on the heritage that has been retained and developed by current set theory. The whole transfinite landscape can be viewed as the result of Cantor's attempt to articulate and solve the Continuum Problem.
Allopurinol: discrimination of antioxidant from enzyme inhibitory activities.

Abstract This study was designed to quantitatively discriminate the specific xanthine oxidase (XO) inhibitory from the relatively nonspecific antioxidant activities of allopurinol, both in vitro and in vivo in the rat. XO activity, determined by the spectrophotometric assay for urate generation over time, was completely inhibited in vitro by allopurinol at concentrations ≥ 200 μM. Allopurinol's antioxidant activity was determined in vitro using a linolenic acid peroxidation (LAP) assay. Although the known antioxidant butylated hydroxytoluene effectively inhibited LAP (80% inhibition of malondialdehyde generation at 101 μM), allopurinol (101–103 μM) did not inhibit this LAP (p
In vivo brain incorporation of [1-14C]arachidonate in awake rats, with or without cholinergic stimulation, following unilateral lesioning of nucleus basalis magnocellularis.

Abstract Regional brain incorporation of a radiolabeled unsaturated fatty acid, [1- 14 C]arachidonic acid ( 14 C-AA), was measured in awake rats following unilateral lesioning of the nucleus basalis magnocellularis (NBM). Right-sided lesions were produced in 3-month-old, male rats by stereotaxic injection of 10 μg ibotenic acid. Two weeks after lesioning, rats were subjected to one of two protocols: (1) 5 min intravenous infusion of 14 C-AA (170 μCi/kg); or (2) i.p.injection of arecoline (5 mg/kg), a cholinergic agonist, followed by 5 min intravenous infusion of 14 C-AA. All animals were killed 15 min postinfusion. Brains were frozen and sectioned for quantitative autoradiography or were stained for acetylcholinesterase (AChE). Animals with unilateral NBM lesions displayed reduced AChE staining in prefrontal, frontal and parietal cortices of the lesioned side, but there was no right-left difference in incorporation of 14 C-AA without cholinergic stimulation. Arecoline administration increased 14 C-AA incorporation into the prefrontal and frontal cortices ipsilateral to the NBM lesion as compared to the contralateral side and the increase was most prominent in deeper cortical layers such as layers IV and V. Right-left differences in incorporation were not apparent in parietal, temporal, or occipital cortices, where reduction of AChE activity was minimal or absent, nor in subcortical structures. The results suggest that the intravenous 14 C-AA technique combined with cholinergic stimulation can be used to detect compensatory regulation of phospholipid-coupled signal transduction caused by a deficit in cholinergic input into the cerebral cortex.
The Effect of Finasteride on the Expression of Vascular Endothelial Growth Factor and Microvessel Density: A Possible Mechanism for Decreased Prostatic Bleeding in Treated Patients

ABSTRACTPurpose: Several studies have confirmed the benefit of finasteride in limiting hematuria from benign prostatic hyperplasia. Vascular endothelial growth factor (VEGF), a potent stimulator of angiogenesis, and microvessel density have been independently evaluated in the mechanism of decreased bleeding observed in patients treated with finasteride. We evaluated the expression of VEGF and suburethral prostatic microvessel density in patients with benign prostatic hyperplasia treated with finasteride.Materials and Methods: The study included 24 patients undergoing prostatic surgery for benign disease, of whom 12 were given finasteride for a minimum of 6 weeks before surgery and the remaining 12 served as controls. Sections from the prostatic urothelium and hyperplastic prostate were individually stained for CD34 specific for nascent blood vessels and VEGF. Analysis of each specimen was performed in a blinded fashion. Microvessel density was calculated by counting the number of positively stained blood ...
Memory-enabled autonomic resilient networking

It is becoming increasingly challenging for the contemporary Internet to satisfy the explosion in networking services and applications with their widely diverse and dynamic QoS requirements and resource demands. For smarter networking management and operations, we hypothesize that next generation networks should be endowed with “memory”-like (i.e., functionally similar to human memory) capabilities and should explicitly manage their resources and services. In this paper, we introduce SmartNet, a new memory-enabled autonomic network architecture that is scalable, resilient and adaptable at runtime. SmartNet's memory, we term NetMem, manages data related to multiple networking concerns, namely application, communication, and resource concerns. SmartNet's NetMem maintains “knowledge” - the fourth networking concern in our networking model - in a distributed knowledge plane that can be rapidly accessed in a simple and systematic way by SmartCells (SmartNet's basic building block) and the services they implement. Each SmartCell has intrinsic monitoring, control and analysis capabilities and can acquire resources on demand. For scalability and to facilitate inter-communications and services' support between SmartCells, regions, termed CellDomains, may be dynamically formed. CellDomains would incorporate favored services or resources. Our simulation results demonstrate an improvement in networking operations with our memory-enabled network management.
Predicting the production rates of cosmogenic nuclides in extraterrestrial matter

Abstract The production rates of nuclides made by the galactic and solar cosmic rays are important in the interpretations of measurements made with lunar samples, meteorites, and cosmic spherules. Production rates of cosmogenic nuclides have been predicted by a variety of methods that are reviewed in this paper, ranging from systematic studies of one or a group of meteorites to purely theoretical calculations. Production rates vary with the chemical composition and the preatmospheric depth of the sample and with the size and shape of the object. While the production systematics for cosmogenic nuclides are fairly well known, our ability to predict their production rates can be improved, with a corresponding increase in the scientific return. Additional detailed studies of cosmogenic nuclides in extraterrestrial objects are needed, especially for fairly small and very large objects. Nuclides made in simulation experiments and cross sections for many major nuclear reactions should be measured. Such studies are especially needed for the long-lived radionuclides that have only recently become readily measurable by accelerator mass spectrometry.
Thiocalix[4] arenes. I. Synthesis and structure of ethylthiocalix[4]arene methyl ether and the related structure of bromocalix[4]arene methyl ether

Bromocalix[4]arene methyl ether serves as a precursor in the synthesis of the title thiocalixarene via the reagent CuSEt. Ethylthiocalix[4]arene methyl ether crystallizes in the monoclinic space groupP21/c witha = 20.577(9),b, = 10.722(5),c = 20.315(9) A, β = 120.46(4)°, andDc = 1.24 g cm−3 forZ = 4. Refinement based on 1441 observed reflections led toR = 0.080. The configuration of the calixarene lies between the partial cone and the 1,3-altemate conformations. Bromocalix[4]arene methyl ether crystallizes in the triclinic space groupPI witha = 12.283(7),b = 17.658(9),c = 18.118(6) A, α = 90.25(6), β = 105.95(4), γ = 105.11(6)°, andDc = 1.68 g cm−3 forZ = 4. Refinement based on 3028 observed reflections led toR = 0.083. The unit cell also contains four CHCl3 molecules which exist pairwise enclathrated by six calixarenes. The partial cone conformation of the bromocalixarene is identical to that of ethylthiocalix[4]arene methyl ether.
Could you use a multidisciplinary care team app

Information technology generally serves 1 of 2 purposes: to replace tedious tasks or to extend the capabilities of the user. In health care, we are fortunate to have numerous opportunities to extend our capabilities. In this article, we explore how mobile and Web-based technologies can address the growing need to collaborate with all those concerned in care provision.
Few-Body Form Factor Measurements in Hall A of JLab

There is an active program of few-body form factor measurements in Hall A of Thomas Jefferson National Accelerator Facility (Jefferson Laboratory). Recent measurements of the deuteron elastic electric, A(Q2), and magnetic, B(Q2), structure functions will be presented. Planned measurements of the form factors of 3He and 4He will also be discussed.
Facilitated glucose transport across the retinal pigment epithelium of the bullfrog (Rana catesbiana)

Transport studies of glucose analogs [ 3 H]3-O-methyl- d -glucose (m d -glu) and l -[ 14 C]glucose ( l -glu) across the isolated retinal pigment epithelium (RPE) of the bullfrog was undertaken to determine whether the glucose transport mechanism was dependent upon the postulated ion-transport scheme and/or whether glucose transport is insulin-mediated. In addition, metabolic inhibitors were tested to explore the energy requirements of glucose transport across the RPE. Flux studies of m d -glu and l -glu performed with mounted RPE tissues, with short circuit current (SCC) and potential difference (PD) monitored via automatic voltage clamp apparatus, indicate that transport is clearly stereospecific with d -glucose being transported at least 13 times faster than l -glucose. The system was found to be saturable with a K m of about 24 m m glucose and V max of 1400 nmol cm −2 hr −1 . Unidirectional Michaelis-Menten constants indicate that the RPE glucose carrier is accessible for transport from either the choroid or retinal side and a bidirectional facilitated diffusion mechanism is suggested. Insulin had no effect on either ion transport (SCC) or glucose transport (passive or facilitated). Both aerobic and anaerobic energy inhibitors decreased ion transport to less than 25% of control, but had little effect if any, on glucose transport across the isolated RPE. Sodium iodoacetate decreased ion transport by 90% of control, but a much slower decrease in facilitated glucose transport of 22% of control suggests that carrier energy requirements, if any, are not direct or immediate. Osmotic studies performed with sucrose and glucose suggest that elevations in osmolarity increase passive glucose movement and decrease facilitated glucose-transport rates. Glucose was found to be much more detrimental to glucose transport than sucrose, suggesting that at high concentrations molecular glucose decreases facilitated transport and increases passive glucose movement by a mechanism other than can be accounted for by osmotic considerations. A model for RPE glucose transport, consistent with current data, is proposed which translocates d -glucose, via an alternating conformational change of the glucose carrier. This carrier does not require a direct supply of metabolic energy, nor a functioning ion-transport mechanism. At a given moment, a single binding site for d -glucose is postulated to be available on either side of the RPE membrane for glucose translocation, although binding site affinity for glucose could differ on each side.
Cassini observations of Io's visible aurorae

Abstract More than 500 images of Io in eclipse were acquired by the Cassini spacecraft in late 2000 and early 2001 as it passed through the jovian system en route to Saturn (Porco et al., 2003, Science 299, 1541–1547). Io's bright equatorial glows were detected in Cassini's near-ultraviolet filters, supporting the interpretation that the visible emissions are predominantly due to molecular SO2. Detailed comparisons of laboratory SO2 spectra with the Cassini observations indicate that a mixture of gases contribute to the equatorial emissions. Potassium is suggested by new detections of the equatorial glows at near-infrared wavelengths from 730 to 800 nm. Neutral atomic oxygen and sodium are required to explain the brightness of the glows at visible wavelengths. The molecule S2 is postulated to emit most of the glow intensity in the wavelength interval from 390 to 500 nm. The locations of the visible emissions vary in response to the changing orientation of the external magnetic field, tracking the tangent points of the jovian magnetic field lines. Limb glows distinct from the equatorial emissions were observed at visible to near-infrared wavelengths from 500 to 850 nm, indicating that atomic O, Na, and K are distributed across Io's surface. Stratification of the atmosphere is demonstrated by differences in the altitudes of emissions at various wavelengths: SO2 emissions are confined to a region close to Io's surface, whereas neutral oxygen emissions are seen at altitudes that reach up to 900 km, or half the radius of the satellite. Pre-egress brightening demonstrates that light scattered into Jupiter's shadow by gases or aerosols in the giant planet's upper atmosphere contaminates images of Io taken within 13 minutes of entry into or emergence from Jupiter's umbra. Although partial atmospheric collapse is suggested by the longer timescale for post-ingress dimming than pre-egress brightening, Io's atmosphere must be substantially supported by volcanism to retain auroral emissions throughout the duration of eclipse.
Misunderstandings about Male Sexuality

There are several basic misunderstandings, including that ‘men have the best of it’during sex because they are guaranteed the stimulation they need to reach orgasm inside the vagina (considered as their ‘drive’, that is, they ‘need’ to ejaculate inside the vagina) -- such are our current fixed ideas about ‘male sexuality’. Another misunderstanding involves thinking that male sexuality is not delicate, but that ‘a real man’is rather like an automatic machine, that is, his erection should be big, hard and long-term whenever he needs it to be -- leading quite a few men of all ages to rely on drugs to ensure that they have this kind of erection, since it is delicate and can come and go -- whereas ‘a real man’ should be ‘ready to fuck’ whenever an appropriate situation arises (it is believed). But -- what if he does not feel like it? For a long time, many men have complained about the ‘performance pressures’ on them, but somehow the myths continue to be believed by both men and women that ‘a big erection’ is the only real sign of desire, or as the saying goes, ‘you can never change il programma maschile’. No one seems to be questioning the veracity of these fixed ideas about male sexuality, but based on my many years research with over 7,000 men followed by several years’reflection on what they have said, I now question these ‘verities’. I think the real nature of male sexuality is much more polymorphous-perverse and diverse than we have tended to believe.
One-Electron Transfer Reactions of 10-Methyl-9,10-dihydroacridine and the Kinetic Isotope Effects for the Intervening Ionization and Protonation of a Carbon Acid

Oxidations of 10-methyl-9,10-dihydroacridine, AcrH2, with transition-metal reagents that require single-electron processes were studied in acetonitrile/water, 20/80 by volume. The reaction proceeds in three stages: (1) electron transfer yielding AcrH2•+, a very rapid step for Ceaq4+ and IrCl62- but rate-controlling for Feaq3+ (k298/L mol-1 s-1 = 37.9 at μ = 0.1 M and 128 at μ = 1.0 M); (2) reversible and relatively slow ionization/protonation of AcrH2•+/AcrH•; and (3) the final highly exoergic and diffusion-controlled oxidation of AcrH• to AcrH+, the stable product. The second step corresponds to ionization/protonation at carbon. Four isotopically distinct versions of the reactions could be examined, AcrL2 and L2O/L3O+ (L = H, D) in every combination. The primary, secondary, and solvent isotope effects on the rate constants in each direction are all appreciable, and they were resolved by the indicated experiments.
Force and Position Scaling Limits for Stability in Force Reflecting Teleoperation

Many telerobotic systems require the use of a slave robot with large inertial and frictional properties. Using a force sensor on the end effector can hide the slave’s inertia and friction from the user providing a more accurate sense of the environment, but introduces dangers of system instability. Both the position and force scale directly affect the system loop gain and hence stability. This opens up the possibility of trading off between them based on the environment and task. In this paper we derive explicit limits for their product. In particular we consider varying environment stiffnesses, as well as distinguishing impact and contact phases. The theoretical limits closely align with experimental results using a large slave telerobotic system interacting with very soft to nearly rigid environments.© 2008 ASME
El ángel exterminador de Luis Buñuel: auto sacramental cinematográfico

El Angel exterminador is an "auto sacramental" for our time and it is more dose to the theatrical Spanish tradition than to the French existentialist works to which many critics use to compare the Bunuel's films. This essay is an attempt to explore some aspects of biblical and literary motifs which interfere on the structure of film . One can observe important episodes related to de Genesis, to the Apocalypses and to Calderon de la Barca "auto sacramental" El gran teatro del mundo.
Optical pumping of cesium in high magnetic fields

Abstract Cs has been optically pumped in magnetic fields ranging from 1kG to 100 kG. The cross section for the destruction of Cs electronic spin polarization in Ne has been measured to be 2.2 × 10 -22 cm 2 , with an effective correlation time shorter than 6 × 10 -13 sec.
An on-line computer system in use with low-energy nuclear physics experiments

Abstract A description is given of a computing system used on-line with experiments performed at the 4 MeV Van de Graaff and the tandem Van de Graaff accelerators at Argonne National Laboratory. The requirements for the system are listed and the hardware and software obtained to fulfill these requirements are described. Some typical applications of the system are given.
The Rise of the Spurcalia: Medieval Festival and Modern Myth

Multiple scholars over the last two centuries have argued that Germanic pagans celebrated a solar festival in February, called the Spurcalia. While there is no consensus about the purpose of this festival (with everything from divination, to the changing of the seasons, to ritual purification suggested), scholars agree that the Spurcalia was a major holiday, which died out only over the course of the early Middle Ages. A closer examination of the medieval sources, however, reveals that this festival never actually existed. Instead, the legend of this holiday arose through a series of misunderstandings on the part of medieval writers, which modern scholarship only compounded. The corrected history of spurcalia makes Germanic polytheism even more mysterious, but it also illustrates how medieval descriptions of paganism reflected clerical ideas about Christianization and the nature of religious worship.
An analysis of reports of depression and suicide in patients treated with isotretinoin.

Abstract Background: The Food and Drug Administration (FDA) has received reports of depression and suicide in patients treated with isotretinoin. Objective: Our purpose was to provide the number and describe the cases of depression and suicide reported to the FDA in US patients treated with isotretinoin and to consider the nature of a possible association between isotretinoin and depression. Methods: An analysis was made of reports of depression, suicidal ideation, suicide attempt, and suicide in US isotretinoin users voluntarily submitted to the manufacturer and the FDA from 1982 to May 2000 and entered in the FDA's Adverse Event Reporting System database. Results: From marketing of isotretinoin in 1982 to May 2000, the FDA received reports of 37 US patients treated with isotretinoin who committed suicide; 110 who were hospitalized for depression, suicidal ideation, or suicide attempt; and 284 with nonhospitalized depression, for a total of 431 patients. Factors suggesting a possible association between isotretinoin and depression include a temporal association between use of the drug and depression, positive dechallenges (often with psychiatric treatment), positive rechallenges, and possible biologic plausibility. Compared with all drugs in the FDA's Adverse Event Reporting System database to June 2000, isotretinoin ranked within the top 10 for number of reports of depression and suicide attempt. Conclusion: The FDA has received reports of depression, suicidal ideation, suicide attempt, and suicide in patients treated with isotretinoin. Additional studies are needed to determine whether isotretinoin causes depression and to identify susceptible persons. In the meantime, physicians are advised to inform patients prescribed isotretinoin (and parents, if appropriate) of the possibility of development or worsening of depression. They should advise patients (and parents) to immediately report mood swings and symptoms suggestive of depression such as sadness, crying, loss of appetite, unusual fatigue, withdrawal, and inability to concentrate so that patients can be promptly evaluated for appropriate treatment, including consideration of drug discontinuation and referral for psychiatric care. (J Am Acad Dermatol 2001;45:515-9.)
Lipid Rafts-Association And Anti-apoptotic Function Of Prohibitin In Ultraviolet B Light-irradiated HaCaT Keratinocytes

Upon UVB irradiation, an alternation of major lipid raft components can lead to the recruitment/activation of rafts-associated proteins and initiation of downstream apoptotic signalling pathways. We used two-dimensional gel electrophoresis (2-DE) to identify potential regulators of UVB-induced apoptosis and mass spectrometry fingerprint analysis to identify proteins that are altered in the rafts after UVB irradiation. Our data show that levels of several proteins, including prohibitin (PHB), were changed in lipid rafts after UVB irradiation. We also demonstrate that while total PHB expression was not changed, the protein was enriched in lipid rafts after UVB irradiation. Reduced expression of PHB using siRNA knockdown resulted in an increase in cellular apoptosis after UVB irradiation. Based on these results, we propose that PHB protects keratinocytes from UVB-induced apoptosis.
Comparison of astigmatism after penetrating keratoplasty by experienced cornea surgeons and cornea fellows.

Purpose We compared surgically induced astigmatism after penetrating keratoplasty performed by supervised cornea fellows and experienced cornea surgeons. Methods Data were collected by retrospective chart review of 166 cases (166 eyes) of penetrating keratoplasty: 63 performed by two cornea surgeons and 103 by four cornea fellows. Astigmatism was calculated using scalar and vector methods. Vector analysis was performed on 109 of 166 eyes. Two techniques were compared: intraoperative keratometry and suture adjustment and the torque-antitorque running suture technique with no intraoperative keratometry or suture adjustment. Results Mean surgically induced scalar astigmatism changed from preoperative astigmatism by 3.27 diopters (fellows) and 2.94 diopters (attending surgeons). In 109 cases, surgically induced vector cylinder changed from preoperative astigmatism by 4.21 diopters at 98 degrees (fellows) and 4.25 diopters at 114 degrees (surgeons). Surgically induced vector astigmatism changed from preoperative astigmatism by 4.67 diopters at 93 degrees in the first 6 months (fellows) and by 3.79 diopters at 103 degrees in the second 6 months. Analysis of x-axis and y-axis components of the surgically induced vector cylinder showed that the majority of the astigmatism was induced in the y-axis and that this difference was significant ( P Conclusions Penetrating keratoplasty performed by supervised cornea fellows resulted in similar rates of surgically induced vector astigmatism, surface asymmetry, and surface regularity as that by experienced surgeons. Fellows induced significantly more with-the-rule astigmatism, but this tendency decreased with further training. Penetrating keratoplasty astigmatic outcomes were not significantly different whether or not intraoperative keratometry and suture adjustment were utilized. This study supports the concept that increased experience with corneal transplantation improves the outcome of penetrating keratoplasty by using the criterion of postoperative astigmatism as a measure.
Negative Schottky barrier between titanium and n-type Si(0 0 1) for low-resistance ohmic contacts

Abstract A metal–semiconductor contact should have a negative Schottky barrier if the metal has a work function less than the electron affinity of the semiconductor. Such a contact would behave ohmically with a low internal resistance. In reality, the electronic states on the semiconductor surface pin the surface Fermi level and make almost all the metals to show a positive Schottky barrier. By eliminating surface states on Si(0 0 1) with a monolayer of selenium, ohmic contacts with a negative Schottky barrier are demonstrated between titanium and n-type Si(0 0 1). These contacts are found to be thermally stable up to 400 °C.
Estimating the Mean with Known Coefficient of Variation

Abstract Searls in 1964 showed that when the coefficient of variation is known, the sample mean is dominated with respect to mean squared error by an improved estimator that makes use of that coefficient. In this article we illustrate that this is true for a general class of estimators. Expressions for the minimum mean squared error and the relative efficiency are given for general distributions. The improvement, as measured by relative efficiency, is seen to be independent of the form of the distribution.
Moments of Change

There is a strong intuition that for a change to occur, there must be a moment at which the change is taking place. It will be demonstrated that there are no such moments of change, since no state the changing thing could be in at any moment would suffice to make that moment a moment of change. A moment in which the changing thing is simply in the state changed from or the state changed to cannot be the moment of change, since these states are respectively before and after the change; moreover, to select one of these moments over the other as the moment of change would be arbitrary. A moment in which the changing thing is neither in the state changed from nor in the state changed to cannot be the moment of change, since there are changes for which it is impossible for something to be in neither state. Finally, the moment of change cannot be a moment in which the changing thing is in both the state changed from and the state changed to, as suggested by Graham Priest and others. Even if, like proponents of this view, we are willing to accept the contradictions that the account entails, it is demonstrated that on such a model, every change would require an infinite number of other changes, every change would take an infinite amount of time, and some changes would occur without occurring at any time. Further, the model is grossly counterintuitive, with the exact nature of the counterintuitive element depending on what model of time and space one endorses. Finally, it is demonstrated that this model is incompatible with the Leibniz Continuity Condition.
Detection of Nisin and Fibrinogen Adsorption on Poly(ethylene Oxide) Coated Polyurethane Surfaces by Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS)

Stable, pendant polyethylene oxide (PEO) layers were formed on medical-grade Pellethane® and Tygon® polyurethane surfaces, by adsorption and gamma-irradiation of PEO-polybutadiene-PEO triblock surfactants. Coated and uncoated polyurethanes were challenged individually or sequentially with nisin (a small polypeptide with antimicrobial activity) and/or fibrinogen, and then analyzed with time-of-flight secondary ion mass spectrometry (TOF-SIMS). Data reduction by robust principal components analysis (PCA) allowed detection of outliers, and distinguished adsorbed nisin and fibrinogen. Fibrinogen-contacted surfaces, with or without nisin, were very similar on uncoated polymer surfaces, consistent with nearly complete displacement or coverage of previously-adsorbed nisin by fibrinogen. In contrast, nisin-loaded PEO layers remained essentially unchanged upon challenge with fibrinogen, suggesting that the adsorbed nisin is stabilized within the pendant PEO layer, while the peptide-loaded PEO layer retains its ability to repel large proteins. Coatings of PEO loaded with therapeutic polypeptides on medical polymers have the potential to be used to produce anti-fouling and biofunctional surfaces for implantable or blood-contacting devices.
Capability of Surface-Based Clear-Air Doppler Radar for Monitoring Meteorological Structure of Elevated Layers

Abstract Radars and acoustic sounding systems sense properties of the turbulence structure of the atmosphere. If atmospheric turbulence can be related to the mean gradient parameters, Doppler radars and acoustic sounders can provide information about height profiles of quantities such as temperature and refractive index as well as wind in stable regions of the atmosphere. In this paper turbulent and mean quantities were measured on the 300 m meteorological tower at the Boulder Atmospheric Observatory near Erie, Colorado, and the relationships between the turbulent and mean gradient quantities were examined in order to evaluate hypotheses for simplifying the kinetic energy balance and refractive index variance equations. FM-CW radar measurements of backscattered power and Doppler spectral width were also made for comparison with tower-measured refractive index spectra and Doppler velocity spectra. Height distributions of the turbulent dissipation rate within stable layers are shown and viscous cutoff radar...
Structural insight into serine protease Rv3671c that Protects M. tuberculosis from oxidative and acidic stress.

Rv3671c, a putative serine protease, is crucial for persistence of Mycobacterium tuberculosis in the hostile environment of the phagosome. We show that Rv3671c is required for M. tuberculosis resistance to oxidative stress in addition to its role in protection from acidification. Structural and biochemical analyses demonstrate that the periplasmic domain of Rv3671c is a functional serine protease of the chymotrypsin family and, remarkably, that its activity increases on oxidation. High-resolution crystal structures of this protease in an active strained state and in an inactive relaxed state reveal that a solvent-exposed disulfide bond controls the protease activity by constraining two distant regions of Rv3671c and stabilizing it in the catalytically active conformation. In vitro biochemical studies confirm that activation of the protease in an oxidative environment is dependent on this reversible disulfide bond. These results suggest that the disulfide bond modulates activity of Rv3671c depending on the oxidative environment in vivo.
SpSJoin: parallel spatial similarity joins

A spatial similarity join of two geospatial datasets finds pairs of records that are simultaneously similar on spatial and textual attributes. Such join is useful for a variety of applications, like data cleansing, record linkage, duplications detection and geocoding enhancement. Efficient techniques exist for the individual joins on either spatial or textual attributes. However, the combined problem has received much less research attention. This paper presents the SpSJoin (Spatial Similarity join) system to fill in this need. SpSJoin is a platform that merges geospatial and text processing techniques for efficiently performing spatial similarity joins. The platform leverages parallel computing with MapReduce to tackle scalability issues in joining large datasets. The efficiency of the proposed techniques are experimentally validated with a join case for improving the geolocation of entities in a real geospatial dataset with referential entities of another dataset.
Anti‐Laminin‐332 Mucous Membrane Pemphigoid in a 9‐Year Old Girl

Mucous membrane pemphigoid (MMP), an autoimmune subepithelial blistering disease that predominantly affects the mucous membranes, is usually diagnosed in elderly adults. Early diagnosis of MMP is crucial because it tends to run a chronic and progressive course with the potential for devastating scarring of the mucous membranes that may lead to blindness and airway compromise. A subtype of MMP, anti-laminin-332 MMP, is a rare blistering disorder in which autoantibodies are directed against laminin-332 (formerly epiligrin), a structural protein of the epidermal basement membrane. Herein we report what we believe to be the youngest patient diagnosed with anti-laminin-332 MMP, a 9-year-old girl with disease affecting only the oral, pharyngeal, and laryngeal mucosa, with no skin involvement.
Systemic arterial hypertension associated with cardiac surgery

Significant hypertension can develop in 15 to 40 percent of patients undergoing various types of cardiac surgery. These hypertensive episodes can occur at almost any time before, during or after open or closed chest operations. The various hypertensions encountered in this context do not form a homogeneous entity; they are nt due to the same causes and do not necessarily develop by the same mechanisms. Their frequency and seriousness have been demonstrated by reports from many centers: hence, the urgent need for accurate definition of their various types to allow correct identification and therapy. A classification based on well defined clinical events is therefore proposed and possible mechanisms for the more common types of hypertension are reviewed. Prophylactic measures nclude reassurance, attention to details of anesthesia and maintenance of preoperative antihypertensive therapy when indicated; for patients with coronary artery disease, preventive nitrate therapy as well as prompt attention to chest pain is essential. Both general and specific antihypertensive measures to control the more common types of hypertension complicating cardiac surgery are outlined.
Quantitative description of mitral valve geometry using real-time three-dimensional echocardiography.

ObjectivesLeaflet and annular geometry are important determinants of mitral valve (MV) stress. Repair techniques which optimize valvular geometry will reduce stress and potentially increase repair ...
Resort Management, and Timeshare and Vacation Ownership: Introduction

Although resort management possesses numerous distinct features and faces unique operational challenges, this area of management has been often been overlooked by academic researchers since resorts...
The discrepancy in the carbonate found in fish bone and blood.

It has been reported in the literature that fish, to get sufficient oxygen, must overventilate with respect to CO2 and therefore exhibit a low circulating level of bicarbonate.
Voltage, stability and diffusion barrier differences between sodium-ion and lithium-ion intercalation materials

To evaluate the potential of Na-ion batteries, we contrast in this work the difference between Na-ion and Li-ion based intercalation chemistries in terms of three key battery properties—voltage, phase stability and diffusion barriers. The compounds investigated comprise the layered AMO2 and AMS2 structures, the olivine and maricite AMPO4 structures, and the NASICON A3V2(PO4)3 structures. The calculated Na voltages for the compounds investigated are 0.18–0.57 V lower than that of the corresponding Li voltages, in agreement with previous experimental data. We believe the observed lower voltages for Na compounds are predominantly a cathodic effect related to the much smaller energy gain from inserting Na into the host structure compared to inserting Li. We also found a relatively strong dependence of battery properties on structural features. In general, the difference between the Na and Li voltage of the same structure, ΔVNa–Li, is less negative for the maricite structures preferred by Na, and more negative for the olivine structures preferred by Li. The layered compounds have the most negative ΔVNa–Li. In terms of phase stability, we found that open structures, such as the layered and NASICON structures, that are better able to accommodate the larger Na+ ion generally have both Na and Li versions of the same compound. For the close-packed AMPO4 structures, our results show that Na generally prefers the maricite structure, while Li prefers the olivine structure, in agreement with previous experimental work. We also found surprising evidence that the barriers for Na+ migration can potentially be lower than that for Li+ migration in the layered structures. Overall, our findings indicate that Na-ion systems can be competitive with Li-ion systems.
Hyperoxic ventilatory responses of high altitude acclimatized cats

Abstract We have examined the effect of steady-state hyperoxia on the ventilation of sea level (SL) cats and cats acclimatized to simulated high altitude (HA) at 5500 m for three weeks. Three groups of cats were studied. In group I, the ventilatory responses to 10%, 21% and 100% O 2 were studied at SL, and after acclimatization to HA, the ventilatory responses to 10% and 100% O 2 were measured. In group II the ventilatory responses and femoral artery and superior sagittal sinus blood gases were measured in two sets of cats, one at SL and one at HA, during exposure to the gases outlined in group I. In group III, we examined the effect of chronic vagotomy on the ventilatory responses to the gas mixtures outlined in group I. Breathing 100% O 2 at SL had no significant effect on ventilation, tidal volume, respiratory frequency, or cerebral blood flow (inferred from the cerebral veno-arterial CO 2 difference). Ventilation was constant in the HA acclimatized cats while breathing 10% and 100% O 2 , but the ventilatory pattern changed dramatically during hyperoxia: respiratory frequency increased and tidal volume fell. Breathing 100% O 2 was associated with changes in CBF, and venous P CO 2 that might be expected to stimulate ventilation, but the change in ventilatory pattern suggests to us that hyperoxic disinhibition of central respiratory processes (which were modified by HA acclimization) is the mechanism whereby ventilation is sustained during hyperoxia at HA. After vagotomy at HA, ventilation constant remained while breathing 100% O 2 , but the chages in respiratory pattern were no longer apparent. Therefore, vagal afferents seem to have a role in determining the pattern, but not necessarily the absolute level, of ventilation during hyperoxia. Cats vagotomized at SL prior to HA exposure did not show any evidence of HA ventilatory acclimatization; thus, the vagi may also play a heretofore unrecognized role in the process of acclimatization.
Iridescent Colors of Hummingbird Feathers

The reflectance spectra of iridescent hummingbird feathers were measured spectrophotometrically for many species, and the structure of the iridescent parts of such feathers investigated by electron microscopy. In the direction normal to the iridescent feather surfaces the structure is found to be periodic in optical dimensions. It consists of stacks of 7–15 elliptical platelets of a material with refractive index ~2, each containing a structurally reinforced air gap. To interpret the reflectance spectra in terms of the surface structures, a theory is given of reflection coefficients of stratified media with analytic refractive-index variations. The theory is applied to the iridescence of hummingbird feathers and accounts quantitatively for the iridescent colors as interference colors by reflection from the observed feather structures.
Direct Stimulation by Growth Hormone of Glucagon and Insulin Release from Isolated Rat Pancreas

The acute effects of bovine growth hormone (bGH) upon the release of glucagon and insulin from the isolated perfused rat pancreas were investigated in the presence of 5.6 mM glucose. Glucagon and insulin release occurred in response to 10(-9), 10(-8) and 10(-7)M bGH within 1-2 min and dissipated within 4 min; a significant increase was seen at 24 sec for glucagon and at 48 sec for insulin. In this concentration range, a dose-response relationship was established for both islet hormones. Upon the addition of 5 mM fumarate, glutamate, and pyruvate, glucagon and insulin release occurred also in response to 10(-11) and 10(-10)M bGH. In the absence of glucose, in response to 10(-7)M bGH, the magnitude of glucagon release was similar to that seen with 5.6 mM glucose; but the release of insulin failed to occur. In the presence of 16.7 mM glucose, the release of glucagon was blunted and that of insulin augmented. The data indicate that growth hormone can stimulate acutely the release of glucagon and insulin at physiological as well as pharmacological concentrations. These rapid and short-lived effects are likely to be direct and not mediated through the generation of somatomedin. The stimulatory effect of growth hormone appears to favor the release of glucagon under conditions of glucose lack, and of insulin under conditions of glucose abundance. These results indicate that growth hormone may have a tonic effect on islet hormone release.