cssi/SciSciGPT-SciSciNet huggingface dataset:
The Value of Accurate High-Resolution and Spatially Continuous Snow Information to Streamflow Forecasts

AbstractPrevious studies have shown limited success in improving streamflow forecasting for snow-dominated watersheds using physically based models, primarily due to the lack of reliable snow water...
Minimax Rates of Estimating Approximate Differential Privacy.

Differential privacy has become a widely accepted notion of privacy, leading to the introduction and deployment of numerous privatization mechanisms. However, ensuring the privacy guarantee is an error-prone process, both in designing mechanisms and in implementing those mechanisms. Both types of errors will be greatly reduced, if we have a data-driven approach to verify privacy guarantees, from a black-box access to a mechanism. We pose it as a property estimation problem, and study the fundamental trade-offs involved in the accuracy in estimated privacy guarantees and the number of samples required. We introduce a novel estimator that uses polynomial approximation of a carefully chosen degree to optimally trade-off bias and variance. With $n$ samples, we show that this estimator achieves performance of a straightforward plug-in estimator with $n \ln n$ samples, a phenomenon referred to as effective sample size amplification. The minimax optimality of the proposed estimator is proved by comparing it to a matching fundamental lower bound.
Radical Ion Probes. 6. Origin of the High Intrinsic Barrier to Nucleophile-Induced Ring Opening of Arylcyclopropane Radical Cations

Radical cations generated from 1-cyclopropylnaphthalene (1), 1-bromo-4-cyclopropylnaphthalene (2), and 2-cyclopropylnaphthalene (3) were studied electrochemically. Oxidation of all these substrates...
Multi-Category Fairness in Sponsored Search Auctions.

Fairness in advertising is a topic of particular concern motivated by theoretical and empirical observations in both the computer science and economics literature. We examine the problem of fairness in advertising for general purpose platforms that service advertisers from many different categories. First, we propose inter-category and intra-category fairness desiderata that take inspiration from individual fairness and envy-freeness. Second, we investigate the "platform utility" (a proxy for the quality of the allocation) achievable by mechanisms satisfying these desiderata. More specifically, we compare the utility of fair mechanisms against the unfair optimal, and we show by construction that our fairness desiderata are compatible with utility. That is, we construct a family of fair mechanisms with high utility that perform close to optimally within a class of fair mechanisms. Our mechanisms also enjoy nice implementation properties including metric-obliviousness, which allows the platform to produce fair allocations without needing to know the specifics of the fairness requirements.
A Decade of Single Center HeartWareTM HVADTM Experience

Purpose Left ventricular assist device (LVAD) implantation has become a standard of care in the treatment of end-stage heart failure, either as bridge-to-transplant, bridge-to-eligibility, or destination therapy. Although caseloads are rising worldwide and the number of patients who have been supported for longer durations are increasing, no large cohort data on long-term outcomes exist. Here, we present our 10-year single center HeartWareTM HVADTM experience, describe changes in our surgical strategies, and provide long-term results. Methods From 12/2009 to 06/2019, 175 patients underwent HVADTM LVAD implantation for ischemic (34%), non-ischemic (65%) or combined (1%) cardiomyopathy. A retrospective data analysis was performed with a focus on technical aspects and follow-up data. Results Mean age at implantation was 54±13 years, 47 patients (27%) were female. The INTERMACS® levels were 1 (19%), 2 (35%), 3 (28%), 4 (15%) or 5 (2%). Fourteen percent required temporary mechanical right heart support. Seventeen percent needed readmission within the first month post HVADTM implantation. 30-day mortality was 7%. The overall survival Kaplan-Meier estimate is shown in figure 1. Forty percent underwent heart transplantation 9±6 months after LVAD implantation. Conclusion This is to date the largest single center analysis of patients undergoing HVADTM LVAD implantation. A minimally invasive approach is feasible in a high percentage where preoperative imaging and planning is essential to guide decision making. Long-term survival is substantial and rates of common complications remain moderate.
A mimetic method for polygons

Abstract A new method for mimetic interpolation on polygonal meshes is described. This new method is based on harmonic function interpolation. Explicit formulas for harmonic functions on general polygons do not exist, so truncated harmonic polynomial expansions are used for computational efficiency. We show that the naive harmonic polynomial expansion, is not stable for arbitrary polygons. However, higher level truncations of harmonic interpolations are stable and accurate. This new method is shown to be a direct extension of the lowest order Raviart-Thomas finite elements to polygons. This method is also a direct extension of the finite volume MAC method to polygons. The accuracy of the interpolation is shown to be first-order irrespective of the polynomial truncation level. However the accuracy of vector Laplace equation solutions using this inner product is shown to be second-order accurate, in keeping with other lowest order Mimetic methods. The versatility of this numerical method is demonstrated on a multiphase incompressible flow problem with a density jump of 1000, on a moving polygonal mesh.
Endogenous cases and the evolution of the common law

I develop a dynamic model of judge‐made law in which the ideal legal rule is unknown but can be learned. In contrast to existing articles, the flow of cases heard by the court is affected by the court's prior decisions. The model highlights the significance of this feedback in explaining when and why the court will write broader or narrower opinions, and the long‐run properties of common law. In equilibrium, the law settles endogenously, because the incentives to make legally controversial choices disappear as the law evolves. Settled law exhibits residual uncertainty and ambiguity, and potentially implements inefficient outcomes.
Adaptive Behavior and the Role of Primary Somatosensory Cortex

Behavioral experience and flexibility are crucial for survival in a constantly changing environment. What are the neuronal processes that selectively transform dynamic sensory information into an appropriate behavioral response, and how do these processes adapt to changes in the environment? Here, we use voltage imaging to measure signals in primary somatosensory cortex (S1) during sensory learning and behavioral adaptation in the mouse. We found that in response to changing sensory stimulus statistics, mice adopt a task strategy that modifies their detection behavior in a context dependent manner as to maintain reward expectation. Correspondingly, neuronal activity in S1 shifts from simply representing stimulus properties to adaptively representing stimulus context in an experience dependent manner. Our results suggest that neuronal signals in S1 are part of an adaptive and dynamic framework that facilitates flexible behavior as an individual gains experience.
Myocardial Hypertrophy and Compensatory Increase in Systolic Function in a Mouse Model of Oxidative Stress

Free radicals, or reactive oxygen species, have been implicated as one of the primary causes of myocardial pathologies elicited by chronic diseases and age. The imbalance between pro-oxidants and antioxidants, termed “oxidative stress”, involves several pathological changes in mouse hearts, including hypertrophy and cardiac dysfunction. However, the molecular mechanisms and adaptations of the hearts in mice lacking cytoplasmic superoxide dismutase (Sod1KO) have not been investigated. We used echocardiography to characterize cardiac function and morphology in vivo. Protein expression and enzyme activity of Sod1KO were confirmed by targeted mass spectrometry and activity gel. The heart weights of the Sod1KO mice were significantly increased compared with their wildtype peers. The increase in heart weights was accompanied by concentric hypertrophy, posterior wall thickness of the left ventricles (LV), and reduced LV volume. Activated downstream pathways in Sod1KO hearts included serine–threonine kinase and ribosomal protein synthesis. Notably, the reduction in LV volume was compensated by enhanced systolic function, measured by increased ejection fraction and fractional shortening. A regulatory sarcomeric protein, troponin I, was hyper-phosphorylated in Sod1KO, while the vinculin protein was upregulated. In summary, mice lacking cytoplasmic superoxide dismutase were associated with an increase in heart weights and concentric hypertrophy, exhibiting a pathological adaptation of the hearts to oxidative stress.
Jumping from Volatility Surface to Exotic Option Price

The volatility feature approach (VFA) to pricing options demands an underlying model to generate volatility surfaces and option parameters to learn model-fitted prices. Prior literature explores controlled experiments using one model to represent “true” market surfaces while choosing an alternative model to generate training surfaces and prices. Accuracy is therefore constrained by the low-dimensional manifold of models used to generate training data. This article explores implementing variational autoencoders trained on historic market data to generate training data more representative of true market surfaces. It is observed in general that a neural network trained via variational autoencoder surfaces increases model specific pricing accuracy against a neural network trained on model generated surfaces.
Positive chronotropic effect caused by transthoracic ultrasound in heart of rats.

Pulsed ultrasound can produce chronotropic and inotropic effects on the heart with potential therapeutic applications. Fourteen 3-month-old female rats were exposed transthoracically to 3.5-MHz 2.0-MPa peak rarefactional pressure amplitude ultrasonic pulses of increasing 5-s duration pulse repetition frequency (PRF) sequences. An increase in the heart rate was observed following each PRF sequence: an ∼50% increase after the 4-5-6 Hz sequence, an ∼57% increase after the 5-6-7 Hz sequence, and an ∼48% increase after the 6-7-8 Hz sequence. Other cardiac parameters showed a normal or indicated a compensatory decrease at 3 and 15 min post-ultrasound compared to control.
Pediatric intracranial neurenteric cyst of the oculomotor nerve: a case-based review.

Neurenteric cysts (NECs) of the central nervous system (CNS) are uncommon congenital entities arising from embryonal elements. Intracranial NECs in the pediatric population are rare. The authors describe the presentation, radiographic imaging, and pathologic findings of an 11-year-old boy with a right oculomotor nerve NEC. A literature review was performed to identify additional cases of pediatric intracranial NECs published in the English language, over the past 30 years (1990–2020). The authors discuss the presentation, investigations, management, and prognosis of this interesting entity. We describe an 11-year-old boy who presented to neurosurgical attention with disconjugate gaze, anisocoria, and ptosis. Magnetic resonance imaging (MRI) demonstrated a lobulated, cystic, and peripherally enhancing mass involving the right oculomotor nerve. The patient underwent pterional craniotomy for drainage of the cyst and subtotal resection of the cyst wall. The tan-colored mass was displacing the basilar artery, compressing the cerebral peduncle, and adherent to the inferior surface of the tentorium. The lesion was within the oculomotor nerve and splitting the fibers, and the cystic contents were thick and mucinous. Histopathological examination of the specimen demonstrated a thin fibrous cyst wall with scattered inflammatory cells and lined by simple columnar epithelium containing mucin. The lining cells were immunoreactive with epithelial membrane antigen (EMA) and pan-keratin AE1/AE3. The diagnosis of a NEC was rendered. A comprehensive literature review of pediatric intracranial NECs yielded 46 additional lesions published in the literature, involving the skull base, posterior fossa, cerebral convexity, and cranial nerves. NECs present with local mass effect and less commonly, with aseptic meningitis or intracystic hemorrhage. Maximal safe GTR remains the mainstay management, although cyst drainage and marsupialization, cyst shunting, and fenestration of cystic contents into the ventricle or basal cisterns have been reported with variable success. CNS NECs are rare congenital entities; although they occur less frequently in the intracranial components compared to the spine, their diagnosis and management should be considered for intracranial cystic lesions. Maximal safe GTR is the mainstay treatment and frequently yields favorable outcomes.
Effect of EDTA decalcification on estrogen receptor and progesterone receptor immunohistochemistry and HER2/neu fluorescence in situ hybridization in breast carcinoma.

Summary Bone is the most common site of metastasis in breast carcinoma (BC). Treatments for metastatic BC depend on various factors, including the tumor's estrogen receptor (ER), progesterone receptor (PR), and HER2 status. Bone biopsies require decalcification which may affect the accuracy of ER and PR immunohistochemistry (IHC) and HER2 situ hybridization (FISH) studies. Ethylenediaminetetraacetic acid (EDTA) decalcifying solutions have been theorized to have no significant impact on ER and PR IHC or HER2 FISH analyses. We completed a prospective study of the effect of EDTA decalcification on ER and PR IHC and HER2 FISH in 29 cases of BC. Samples from 29 BC resections were collected and formalin fixed between 12 and 24 h. Control samples were routinely processed, whereas test samples were placed in EDTA for 48 h. ER and PR slides were blinded, randomized, and evaluated. Blinded samples underwent HER2 FISH assays where an average HER2 copy number and HER2/CEP17 ratio were calculated. Paired differences between EDTA and control samples were compared for ER and PR positivity, average HER2 copy number, and HER2/CEP17 ratios using paired-samples t-tests (PST) and Wilcoxon signed-rank test (WSR). PST and WSR tests yielded no significant difference between EDTA and control tissue for ER% (PST: P = 1; WSR: P = 0.916), PR% (PST: P = 0.973; WSR: P = 0.984), HER2 copy number (PST: P = 0.124; WSR: P = 0.103), and HER2/CEP17 ratio (PST: P = 0.25; WSR: P = 0.105). The use of EDTA in bony tissue is therefore a valid decalcification method to ensure accurate assessment of ER and PR IHC and HER2 FISH in metastatic BC.
Two Tests of the Direction of Elongation of Poly(ADP-ribose): Residues are Added at the Polymerase-Proximal Terminus

Previous experimental approaches have suggested that poly(ADP-ribose) synthesis begins with the ADP-ribosylation of an “acceptor” protein, and that the poly(ADP-ribose) chain is elongated by the repetitive “distal” addition of further ADP-ribose residues to the 2′OH end (1). However the first product of poly(ADP-ribose) synthesis is an auto-modified polymerase (1–3), which is difficult to reconcile with distal addition. For this and other reasons we have considered the alternative possibility that a polymerase molecule would build a polymer of ADP-ribose upon itself (proximal addition). We describe here two tests of the direction of elongation of poly(ADP-ribose) both of which support proximal over distal addition.
Building parallel simulations from serial simulators

In order for parallel discrete event simulation (PDES) to have practical impact, PDES tools must hide the complexities of time synchronisation from users and provide capabilities approaching those of industrial quality serial simulators. Typically, PDES tools have been started from scratch thereby requiring a modeler to learn a new and unfamiliar modeling tool. This note describes a parallel simulation tool, the Utilitarian Parallel Simulator, U.P.S. that is distinguished from the above mentioned tools in that it is built on top of an existing, industrial quality serial simulator, CSIM. U.P.S. extends the standard CSIM modeling language by providing a simple and natural mechanism for submodels running on different processors to communicate with one another. The user need not be concerned with time synchronisation, save for specifying which algorithm to use, nor need the user make calls to a low level interprocessor communications library (e.g. a message-passing library such as MPI). U.P.S. was implemented without making any changes to the existing CSIM simulation engine. As such, it implements conservative time synchronisation algorithms. As CSIM has been ported to many uniprocessor platforms, and since U.P.S. is implemented using the MPI standard, U.P.S. is potentially portable to many multiple processor systems. It has been tested and run on two such platforms: the IBM SP2 and the Intel Paragon.
Tail Asymptotics for HOL Priority Queues Handling a Large Number of Independent Stationary Sources

In this paper we study the asymptotics of the tail of the buffer occupancy distribution in buffers accessed by a large number of stationary independent sources and which are served according to a strict HOL priority rule. As in the case of single buffers, the results are valid for a very general class of sources which include long-range dependent sources with bounded instantaneous rates. We first consider the case of two buffers with one of them having strict priority over the other and we obtain asymptotic upper bound for the buffer tail probability for lower priority buffer. We discuss the conditions to have asymptotic equivalents. The asymptotics are studied in terms of a scaling parameter which reflects the server speed, buffer level and the number of sources in such a way that the ratios remain constant. The results are then generalized to the case of M buffers which leads to the source pooling idea. We conclude with numerical validation of our formulae against simulations which show that the asymptotic bounds are tight. We also show that the commonly suggested reduced service rate approximation can give extremely low estimates.
An anatomically realistic temperature phantom for radiofrequency heating measurements

Purpose An anthropomorphic phantom with realistic electrical properties allows for a more accurate reproduction of tissue current patterns during excitation. A temperature map can then probe the worst-case heating expected in the unperfused case. We describe an anatomically realistic human head phantom that allows rapid three-dimensional (3D) temperature mapping at 7T. Methods The phantom was based on hand-labeled anatomical imaging data and consists of four compartments matching the corresponding human tissues in geometry and electrical properties. The increases in temperature resulting from radiofrequency excitation were measured with MR thermometry using a temperature-sensitive contrast agent (TmDOTMA−) validated by direct fiber optic temperature measurements. Results Acquisition of 3D temperature maps of the full phantom with a temperature accuracy better than 0.1°C was achieved with an isotropic resolution of 5 mm and acquisition times of 2–4 minutes. Conclusion Our results demonstrate the feasibility of constructing anatomically realistic phantoms with complex geometries incorporating the ability to measure accurate temperature maps in the phantom. The anthropomorphic temperature phantom is expected to provide a useful tool for the evaluation of the heating effects of both conventional and parallel transmit pulses and help validate electromagnetic and temperature simulations. Magn Reson Med 73:442–450, 2015. © 2014 Wiley Periodicals, Inc.
Basic surgical training of the gynecologist-obstetrician.

Abstract An animal research laboratory is being used to give experience in the basic surgical techniques to the residents in gynecology and obstetrics at The Henry Ford Hospital. Intestinal operations, ureter and bladder operations, vascular repair, research, and cardiac resuscitation are all supervised during a 4 month portion of the residency. Ability and confidence are improved as basic techniques are mastered.
Magnetic circular dichroism of cyclic π-electron systems—25: Oxo derivatives of indazole, benzimidazole and purine

Abstract The simple perimeter model combined with PMO theory and semimpirical calculations is used to rationalize the observed MCD spectra of a series of oxo derivatives of azaindoles, such as caffeine and xanthine. The MCD spectra indicate the presence of substantial amounts of the 9-H tautomers in aqueous solutions of xanthines.
Application of Fuzzy Pattern Recognition of Seismic Damage to Concrete Structures

AbstractThere has been a long-standing desire to identify classes or groupings of buildings that exhibit similar characteristics in response to seismic events. Regional earthquake loss models, post-earthquake safety evaluations, and rapid visual screening of buildings for potential seismic hazards all utilize building damage patterns in some form. Difficulty arises in characterizing seismic building damage due to the inherent uncertainty in both the occurrence of seismic events and uncertainties related to building responses. Various trends in building performance, often based on building characteristics, are frequently listed in the literature. For example, older structures are expected to perform less well than those designed to more recent design codes; however, it remains difficult to characterize building damage due to the rarity and somewhat limited documentation of earthquake building damage. The earthquake engineering field, in its current state, is dominated by probabilistic and/or deterministic ...
SENSITIVITY TO CHANGING CONTINGENCIES IN AN IMPULSIVITY TASK

Using a video-game-based escalating interest task, participants repeatedly encountered a reward that gradually increased in value over a 10-second interval. Responding early in the interval netted less immediate reward than responding later in the interval. Each participant experienced four different reward contingencies for waiting. These contingencies were changed three times as the experiment proceeded. Behavior tracked these changing contingencies, but wait times reflected long-term carryover from the previously assigned contingencies. Both the tendency to respond slowly and the optimality of behavior were affected by the order of contingencies experienced. Demographic variables only weakly predicted behavior, and delay discounting rate in a hypothetical money choice task predicted choice only when the contingencies in the game were weaker.
Cognitive Semantics, Typology, and Culture as a Cognitive System: The Work of Leonard Talmy

Toward. Cognitive Semantics, Volume 1: Concept Structuring Systems. Leonard Talmy. Cambridge, MA: MIT Press, 2000. 565 pp. Toward. Cognitive Semantics, Volume 2: Typology and Process in Concept Structuring.Leonard Talmy. Cambridge, MA: MIT Press, 2000.495 pp.
Heat Losses in D-C. Armature Conductors

The pioneer paper on this subject of copper losses in armature conductors was presented by A. B. Field.4 Since then Field's fundamental premises have been adopted by practically all who have contributed to this subject, both in this country and abroad, although the method of presentation has been modified as the individual thought best. Thus one of the present authors has favored a vector method of analysis that seems to him to have marked advantages. In this paper the vector method is extended to the case of the d-c. machine. Without doubt, it is generally believed that there are extra losses in the armature coil of a d-c. machine when it is undergoing commutation, but that during the major portion of the time, since the current is steady, the loss in the coil is correctly computed by squaring the value of the current and multiplying by the true or ohmic resistance of the coil. This view, however, is not correct. The disturbance in the coil current produced by the process of commutation persists throughout the cycle so that at no time is the current uniformly distributed over the cross-section of the conductor. Although the disturbance and resulting extra loss factor are greatest during commutation, the extra losses are present at all times, even while the current in the coil is steady. The procedure for finding the extra losses is simple. First, the time variation of the coil current must be known and analyzed for its harmonic components.
Developmental aspects of benzodiazepine receptors and GABA-gated chloride channels in primary cultures of spinal cord neurons.

Abstract The developmental aspects of γ-aminobutyric acid (GABA)-benzodiazepine receptor ionophore complex in mouse cultured spinal cord neurons was investigated in vitro. We examined benzodiazepine binding, GABA enhancement of benzodiazepine binding and GABA activation of chloride channels to intact cultured neurons during the development (days 1–14). Specific benzodiazepine binding increased with time from day 3 ( B max =546fmol/mg protein) to day 14 ( B max =1746fmol/mg protein). There was no significant difference in the affinity ( K d ) of [ 3 H]flunitrazepam for its receptor sites from day 3 to 14. Specific binding of [ 3 H]flunitrazepam to the intact cells was also increased in the presence of GABA during all stages of development. The EC 50 value of the GABA concentration (14–16 μM) required to enhance [ 3 H]flunitrazepam binding did not change from day 3 to 14. GABA receptor-activated chloride channels, studied by 36 Cl-influx was also observed at all ages in culture, and indicated an early development (as early as day 3) of these GABA-gated channels. These srudies indicate that GABA-benzodiazepine-ionophore complex develop early in cultured spinal cord neurons, and these neurons provide an ideal system to study GABAergic events.
The effect of "far-lateral hypothalamic" lesions on the wheel-running activity of rats.

Abstract In addition to producing a temporary aphagia and adipsia, destruction of the tuberal region of the hypothalamus lateral and ventral to the fornix (“mid-lateral hypothalamus”) produces a permanent decrease in the wheel-running activity of rats to 10% of preoperative levels. Destruction of a region lying more laterally that includes the extreme lateral portion of the hypothalamus and the adjacent portion of the subthalamus (“far-lateral hypothalamus”) also produces aphagia and adipsia which may be more permanent than that produced by mid-lateral hypothalamic damage and may be cause by the interruption of fiber tracts in this region. Experiments were performed to determine whether far-lateral hypothalamic injury also produces a permanent decrease in wheel-running activity. It was found that none of the rats with far-lateral hypothalamic lesions exhibited a permanent decrease in wheel running activity comparable to that observed in rats with mid-lateral hypothalamic lesions, even though each of the far-lateral hypothalamic lesions damaged one or more of the structures and fiber tracts within the subthalamus.
SFDR Improvement of a Coherent Receiver Using Feedback

A novel coherent optical receiver is proposed and experimentally demonstrated by using a feedback technique capable of reducing the nonlinear distortion in a traditional receiver while retaining the signal to noise ratio.
Parts of the Whole : Cognition, Schemas, and Quantitative Reasoning

Based loosely on ideas of Jean Piaget and Richard Skemp, this Parts of the Whole column considers the construction of knowledge in mathematics and quantitative reasoning. Examples are chosen that illustrate an important cognitive difference between quantitative numeracy and classical mathematics, and which illuminate the particular choices instructors must make in order to teach either or both of these.
A meta‐analysis of positive humor in the workplace

Purpose – The benefits of humor for general well‐being have long been touted. Past empirical research has suggested that some of these benefits also exist in the work domain. However, there is little shared understanding as to the role of humor in the workplace. The purpose of this paper is to address two main gaps in the humor literature. First, the authors summarize several challenges researchers face in defining and operationalizing humor, and offer an integrative conceptualization which may be used to consolidate and interpret seemingly disparate research streams. Second, meta‐analysis is used to explore the possibility that positive humor is associated with: employee health (e.g. burnout, health) and work‐related outcomes (e.g. performance, job satisfaction, withdrawal); with perceived supervisor/leader effectiveness (e.g. perceived leader performance, follower approval); and may mitigate the deleterious effects of workplace stress on employee burnout.Design/methodology/approach – The authors examine...
Major- and trace-element magnetite-melt equilibria

The effects of composition and temperature on the partitioning behavior of Sc, Ni, V, U and Th, and the high field strength elements (HFSE) Zr, Nb, Ta and Hf between magnetite and natural silicate melts were evaluated from doped experiments on natural mafic- to intermediate-composition lavas at 1-atm pressure. Composition was found to be the strongest controlling factor on partitioning behavior. The partition coefficients (D) for Zr, Nb, Hf and Ta correlate with DTi and are similar to one another for any given magnetite-melt pair, but vary from 2 in titanomagnetite. DSc is higher than DZr, DNb, DHf and DTa, and also correlated to DTi. In contrast, Ni is more compatible in Al-Cr-rich magnetites than in titanomagnetites, but is compatible in all magnetite-melt pairs in our experiments. V is generally more compatible than Zr, Nb, Ta and Hf, but its behavior is complicated by its multiple valence states. U and Th are incompatible (D < 0.035) in all magnetites. Expressions were derived to describe the relationship between D and the most strongly correlated parameters, oxide Fe/Mg ratio and Al, and DTi. These patterns of behavior are consistent with the observed miscibility gap between the spinel-group end-members. Equilibrium constants for spinel end-member-melt reactions were parameterized in terms of temperature, pressure and composition. These expressions can be used to predict the temperature and composition of equilibrium spinels. These major-element constraints can also be used to predict spinel-melt partition coefficients using the expressions describing DHFSE as a function of DTi and composition.
Thermally Induced Flux Motion in Superconducting Tin

Direct evidence is presented for thermally induced flux motion in a superconductor. The method consists of setting up the macroscopic Landau domain structure in a thin single crystal of tin and imposing a temperature gradient along the sample. Motion is monitored with the Sharvin point-contact technique, enabling one to deduce an experimental value for the actual velocity of flux motion. The dependence of this velocity on the applied temperature gradient is found to be in fair agreement with a theory due to Clem.
C-terminal-truncated microdystrophin recruits dystrobrevin and syntrophin to the dystrophin-associated glycoprotein complex and reduces muscular dystrophy in symptomatic utrophin/dystrophin double-knockout mice.

C-terminal-truncated (ΔC) microdystrophin is being developed for Duchenne muscular dystrophy gene therapy. Encouraging results have been achieved in the mdx mouse model. Unfortunately, mdx mice do not display the same phenotype as human patients. Evaluating ΔC microdystrophin in a symptomatic model will be of significant relevance to human trials. Utrophin/dystrophin double-knockout (u-dko) mice were developed to model severe dystrophic changes in human patients. In this study we evaluated the therapeutic effect of the ΔR4-R23/ΔC microdystrophin gene (ΔR4/ΔC) after serotype-6 adeno-associated virus-mediated gene transfer in neonatal u-dko muscle. At 2 months after gene transfer, the percentage of centrally nucleated myofiber was reduced from 89.2 to 3.4% and muscle weight was normalized. Furthermore, we have demonstrated for the first time that ΔC microdystrophin can eliminate interstitial fibrosis and macrophage infiltration and restore dystrobrevin and syntrophin to the dystrophin-associated glycoprotein complex. Interestingly neuronal nitric oxide synthase was not restored. The most impressive results were achieved in muscle force measurement. Neonatal gene therapy increased twitch- and tetanic-specific force. It also brought the response to eccentric contraction-induced injury to the normal range. In summary, our results suggest that the ΔR4/ΔC microgene holds great promise in preventing muscular dystrophy.
In utero diagnosis of atrial flutter by means of real-time—directed M-mode echocardiography

Reprint requests: Thomas A. Losure, D.O., Section on Perinatology, Department of Obstetrics and Gynecology, Pennsylvania Hospital, Philadelphia, PA 19 107. complicated prenatal course until the day prior to transfer when a fetal tachycardia at 220 bpm was noted in her referring physician’s office. Her previous visit was 2 weeks earlier and the fetal heart rate was recorded as 160 bpm. In the interim, she had a viral illness lasting 4 days with a mild temperature elevation to 100.5” F and Rulike symptoms. The patient’s past medical history was marked by chronic hypertension treated with bed rest, exogenous obesity, and a history of pyelonephritis. The patient denied any allergies and received no medications during this pregnancy. Upon admission to the hospital, routine blood studies were performed and all were reported as normal. In addition, an electrocardiogram, chest x-ray film, liver function tests, creatinine clearance, serum electrolytes, and urine culture were all normal. There was no evidence of isoimmunization or recent infection. At physical examination she was in no apparent acute distress. The vital signs were normal. The uterine fundus was consistent with dates and the cervix was closed and posterior. The fetal heart rate was 220 bpm. The remainder of the physical examination was within normal limits. A sonogram revealed a single viable fetus in the cephalic presentation with an estimated fetal weight appropriate for
Epoxidation of zeaxanthin and antheraxanthin reverses non-photochemical quenching of photosystem II chlorophyll a fluorescence in the presence of trans-thylakoid ΔpH

The xanthophyll cycle apparently aids the photoprotection of photosystem II by regulating the nonradiative dissipation of excess absorbed light energy as heat. However, it is a controversial question whether the resulting nonphotochemical quenching is soley dependent on xanthophyll cycle activity or not. The xanthophyll cycle consists of two enzymic reactions, namely deepoxidation of the diepoxide violaxanthin to the epoxide-free zeaxanthin and the much slower, reverse process of epoxidation. While deepoxidation requires a transthylakoid pH gradient (delta pH), epoxidation can proceed irrespective of a delta pH. Herein, we compared the extent and kinetics of deepoxidation and epoxidation to the changes in fluorescence in the presence of a light-induced thylakoid delta pH. We show that epoxidation reverses fluorescence quenching without affecting thylakoid delta pH. These results suggest that epoxidase activity reverses quenching by removing deepoxidized xanthophyll cycle pigments from quenching complexes and converting them to a nonquenching form. The transmembrane organization of the xanthophyll cycle influences the localization and the availability of deepoxidized xanthophylls is to support nonphotochemical quenching capacity. The results confirm the view that rapidly reversible nonphotochemical quenching is dependent on deepoxidized xanthophyll.
Large-Angle Pion-Proton Elastic Scattering at High Energies

Differential cross sections for elastic π±−p scattering have been measured at lab momenta of 8 and 12 GeV/c in a momentum-transfer region corresponding to 1.2≤−t≤6 (GeV/c)2. Also, differential cross sections near 180° were measured for 4 and 8 GeV/c pions. At momentum transfers greater than −t=2 (GeV/c)2, the π−p cross sections drop much faster with increasing angle than the corresponding p−p cross sections. Also, in the region −t≃1.3 (GeV/c)2, there is structure in the π−p angular distribution but not in the p−p angular distribution. At −t≃3 (GeV/c)2, the drop in cross section appears to stop and from then on the angular distribution is consistent with isotropy. But in the angular region 170° to 180°, the cross sections have become much larger, and sharp backward peaks are observed. Information is given on the energy and charge dependences and widths of these backward peaks.
Neuropyschological performance in obsessive-compulsive disorder ☆ ☆☆

Abstract Neuropsychological functioning was examined in a group of 18 nondepressed patients with obsessive-compulsive disorder (OCD) and 18 age-, education-, and gender-matched normal controls. A recent nonverbal memory deficit was identified in the patients with OCD. From performance on timed and untimed measures of the same constructs, it appears that OCD patients score more poorly than controls when speed is a factor. Although performance on a timed tactual-spatial motor test was also impaired, it is unclear whether this deficit is attributable to the nonverbal memory and/or speed deficits. Deficits in verbal abilities, including recent verbal memory, were not identified. Results were equivocal for executive function and visual-spatial abilities. The previously established association of recent nonverbal memory abilities with functioning of the right mestal temporal area is discussed in the context of current hypotheses about the neuroanatomic substrate of OCD.
Contributions of Qualitative Research to the Knowledge Base of Normal Communication

As clinical speech-language pathology moves toward a progressive use of qualitative research methodologies and applications for clinical purposes, it is helpful to know how the qualitative paradigm...
The half-lives of alkylating intermediates from diethylnitrosamine and N-nitrosopyrrolidine: a method for the measurement of metabolically generated reactive species.

Abstract The half-times of the α-hydroxylated intermediates formed during metabolism of diethylnitrosamine and N-nitrosopyrrolidine have been determined. The method for determining half-times involved in vitro enzymatic conversion of the nitrosamine to a hydroxylated intermediate followed by trapping of the alkylating species generated from the chemical decomposition of the intermediate as it flowed through a column containing bound nucleophile. Half-times of less than 1 min at pH 7.4, 37°C, were calculated from the distribution of alkylation on the column and the known flow rate of metabolic intermediates through the column. The half-times may be short enough to significantly limit organ distribution.
Age dynamics in scientific creativity

Data on Nobel Laureates show that the age–creativity relationship varies substantially more over time than across fields. The age dynamics within fields closely mirror field-specific shifts in (i) training patterns and (ii) the prevalence of theoretical contributions. These dynamics are especially pronounced in physics and coincide with the emergence of quantum mechanics. Taken together, these findings show fundamental shifts in the life cycle of research productivity, inform theories of the age–creativity relationship, and provide observable predictors for the age at which great achievements are made.
CAUSATION AND RACE

Race is often viewed as a causal variable and “RACE effects” found from regression analyses are sometimes given causal interpretations. I argue that this is a mistaken way to proceed. RACE is not a causal variable in a very important sense of the word, and yet it does have a significant role in causal studies. The key role that RACE can play is to help our understanding of the effects of causes or interventions through the statistical “interaction” of RACE with causal variables, rather than as the main effect of RACE. These ideas are briefly illustrated using data from a study of tests constructed to manipulate the distribution of scores of Black and White test takers.
Duplex Doppler sonography of the umbilical arteries: predictive value in IUGR and correlation with birth weight.

Abstract Forty-three women with either clinically high-risk singleton pregnancies or a predicted fetal weight less than the 10th percentile were studied in their third trimester by duplex Doppler sonography of the free umbilical artery to assess the associations between umbilical arterial flow resistance and intrauterine growth retardation (IUGR) and birth weight. Test criteria included: the greatest (GRI), mean (MRI), and least (LRI) resistive index. The criterion with the strongest association with IUGR ( p = 0.001) was the parameter of the LRI ≥ 0.67 (sensitivity = 78% and specificity = 79% in predicting IUGR). Linear regression analysis showed a nonsignificant correlation between RI and percentile birth weight, with r 2 = 0.05 and p = 0.131. While significant associations can be shown between RI and IUGR, the clinical use of the results of this test should reflect the imprecise nature of these correlations.
Effect of Pulsed High Frequency Electromagnetic Radiation on Embryonic Mouse Palate in vitro

Palatal shelves from 14-day-old embryonic mice were exposed to a 27.12 MHz pulsed non-ionizing radiofrequency (Diapulse) for 20 min followed by 24-hour organ culture in nutrient agar. Diapulse-treated palatal shelves showed induction of cartilage within the mesenchymal compartment and loss of the overlying epithelium in contrast to controls which were free of cartilage. The results are thought to be independent of thermal changes and may be due to calcium flux within the tissue.
Proton therapy for uveal melanomas and other eye lesions.

Charged particle beams are ideal for treating intra-ocular lesions, since they can be made to deposit their dose in the target, while significantly limiting dose received by non-involved ocular and orbital structures. Proton beam treatment of large numbers of uveal melanoma patients consistently achieves local control rates in excess of 95%, and eye retention rates of approximately 90%. Visual preservation is related to initial visual acuity, tumor size and location, and dose received by the macula, disc, and lens. The probability of distant metastasis is increased by larger tumor diameter, more anterior tumor location, and older patient age. Proton therapy is also effective treatment for patients with ocular angiomas, hemangiomas, metastatic tumors, and retinoblastomas, and may be beneficial for patients with exudative (“wet”) age-related macular degeneration.
Interaction of Actin and ADP with the Head Domain of Smooth Muscle Myosin: Implications for Strain-Dependent ADP Release in Smooth Muscle†

Transient kinetic methods were used to study interactions between actin, MgADP, and smooth muscle (chicken gizzard) myosin subfragment 1 (smS1). The equilibrium dissociation constant (Kd) of actin for smS1 was 3.5 nM, tighter than that of skeletal S1 (skS1). Actin binding to smS1 was weakened 5-fold by saturation with ADP compared to 30-60-fold for skS1. The Kd of ADP for smS1 was increased from 1.2 to 5 microM by actin, whereas for skS1 values increased from 2 to 100 microM. Thus, coupling between ADP and actin binding is weaker for smS1. Previous studies show that release of ADP from actin.smS1.ADP produces a tilt of the regulatory domain [Whittaker, M., Wilson-Kubalek, E. M., Smith, J. E., Faust, L., Milligan, R. A., and Sweeney, H. L. (1995) Nature 378, 748-751]. This result was confirmed by independent structural methods; tilting was absent for skS1, and the Kd for ADP was in agreement with the values measured here [Gollub, J., Cremo, C. R., and Cooke, R. (1996) Nat. Struct. Biol. 3, 796-802; Poole, K. I. V., Lorenz, M., Ellison, P., Evans, G., Rosenbaum, G., Boesecke, P., Holmes, K. C., and Cremo, C. R. (1997) J. Muscle Res. Cell Motility 18, 264]. We discuss tilting upon ADP release with respect to our measurements, previous measurements with skS1, and nucleotide concentrations in smooth muscle. We propose that these data suggest a strain-dependent ADP release mechanism that may be accentuated in smooth muscles.
Mesoscale Association of a Low-level Jet Stream with a Squall-Line—Cold-Front Situation

Abstract Wind and temperatures data taken at twelve levels on a television tower near Dallas, Tex., are examined during a squall-line—cold-front situation occurring during the morning hours of 8 May 1961. The observations, supplemented by Fort Worth pibal and radiosonde data, illustrate the presence of a large scale low-level jet stream in the southwesterly flow in advance of the squall line, a wind maximum and marked cooling associated with a thunderstorm outdraft and a separate, smaller scale jet stream which existed within a mesoscale high pressure area between the squall line and the cold front. This mesoscale high, of the type studied by Fujita, is produced by sub-cloud precipitation evaporation. Detailed vertical soundings show the extent of the corresponding subsidence inversion and the resulting effect on the wind speed profile.
Plasma membrane localization and functional rescue of truncated forms of a G protein-coupled receptor

To test the hypothesis that G protein-coupled receptors consist of multiple autonomous folding domains, the rat m3 muscarinic acetylcholine receptor was "split" in all three intracellular (i1-i3) and all three extracellular loops (o2-o4). The six resulting polypeptide pairs (Ni1.Ci1, No2.Co2, etc.) were coexpressed in COS-7 cells and studied for their ability to bind muscarinic ligands and to activate G proteins. In addition, immunocytochemical and ELISA studies were carried out to study the expression and subcellular localization of the individual receptor fragments. Interestingly, all N- and C-terminal receptor fragments studied (except Ni1, which contained only the first transmembrane domain) were found to be localized to the plasma membrane, even when expressed alone. Coexpression of three of the six polypeptide pairs, generated by splitting the m3 muscarinic receptor in the i2, o3, or i3 loop, resulted in receptor complexes (Ni2.Ci2, No3.Co3, and Ni3.Ci3, respectively), which were able to bind muscarinic agonists and antagonists with high affinity. The No3.Co3 and Ni3.Ci3 polypeptide combinations, but not the Ni2.Ci2 complex, were also able to stimulate carbachol-dependent phosphatidyl inositol hydrolysis to a similar maximum extent as the wild type m3 muscarinic receptor. These findings strongly suggest that G protein-coupled receptors are composed of several independent folding units and may shed light on the molecular mechanisms governing receptor assembly and membrane insertion.
Are infant attachment patterns continuously or categorically distributed? A taxometric analysis of strange situation behavior.

Contemporary attachment research is based on the assumption that at least three types of infant attachment patterns exist: secure, avoidant, and resistant. It is not known, however, whether individual differences in attachment organization are more consistent with a continuous or a categorical model. The authors addressed this issue by applying P. E. Meehl's (1973, 1992) taxometric techniques for distinguishing latent types (i.e., classes, natural kinds) from latent continua (i.e., dimensions) to Strange Situation data on 1,139 fifteen-month-old children from the NICHD Study of Early Child Care. The results indicate that variation in attachment patterns is largely continuous, not categorical. The discussion focuses on the implications of dimensional models of individual differences for attachment theory and research.