cssi/SciSciGPT-SciSciNet huggingface dataset:
The relationship between group size and the private provision of public goods

Abstract I consider a symmetric public-good-provision game in which each player’s valuation of the public good is her private information. I show that if the unit hazard rate of valuation is greater (less) than 1 for all valuations above the supply cost, the game has a unique equilibrium which is symmetric. Further, as group size grows, the probability increases (decreases) that the public good is privately supplied.
The effect of central cholinergic and noradrenergic denervation on hippocampal sympathetic ingrowth and apoptosis-like reactivity in the rat

In this study, the effect of intraseptal injection of specific cholinotoxin 192-IgG saporin (SAP) +/- intraperitoneal injection of N-[chloroethyl]-N-ethyl-2-bromobenzylamine (DSP-4) (noradrenergic fiber neurotoxin) was examined in rat hippocampus. Medial septal lesions resulted not only in selective cholinergic denervation of hippocampus (Medial septal lesion + ganglionectomy; SAP + Gx) but also in hippocampal sympathetic ingrowth (IG) of adrenergic fibers (Medial septal lesion + sham ganglionectomy; SAP + IG). Saporin-induced septal lesions produced a significant reduction in hippocampal choline acetyltransferase activity in all tested groups (SAP + IG +/- DSP-4 and SAP + Gx +/- DSP-4), and an increase in noradrenaline concentration in the SAP + IG group. Visualization of noradrenergic fibers by histofluorescence revealed a mixture of fine and thick varicosities in the SAP + IG but only fine fibers in control and SAP + Gx animals. SAP + IG + DSP-4 lesions produced significant reduction in noradrenaline concentration in all groups with a concomitant decrease in visualization of central noradrenergic fibers in dorsal and ventral hippocampus. Treatment of SAP + IG animals with DSP-4 left mostly thick fibers, probably derived from peripheral sympathetic ingrowth. No fluorescence was seen in either the control + DSP-4 or SAP + Gx + DSP-4 animals. Apoptotic-like changes, using in situ oligonucleotide ligation techniques, were also assessed. Proapoptotic changes were seen in the SAP + Gx +/- DSP-4 group as compared to CON +/- DSP-4 groups. SAP + IG regardless of DSP-4 treatment protected hippocampal cells from apoptotic cell death when compared to positive control and SAP + Gx +/- DSP-4 groups. In summary, elevated noradrenaline concentration following specific cholinergic denervation probably reflects compensatory hippocampal ingrowth originating from the peripheral sympathetic system which may be responsible for neuroprotective effects, i.e., antiapoptosis-like effect. Since cholinergic and noradrenergic systems are known to be involved in Alzheimer's disease and related cognitive function, knowing how these neurotransmitters work after specific lesions may be of importance as an animal model of Alzheimer's disease and as a potential target for Alzheimer's disease drug therapies.
Mechanism and Kinetics of Photoisomerization of a Cyclic Disulfide, trans-4,5-Dihydroxy-1,2-dithiacyclohexane

The photolysis of trans-4,5-dihydroxy-1,2-dithiacyclohexane in aqueous and CH2Cl2 solution yields two isomers of 2,3-dihydroxy-1-mercaptotetrahydrothiophene, characterized by 1H and 13C NMR and negative ion electrospray mass spectrometry. Product formation in water is independent of the presence of oxygen and the concentration of trans-4,5-dihydroxy-1,2-dithia-cyclohexane and involves intramolecular 1,5-H-transfer, followed by cyclization through thiophilic or nucleophilic addition, or 1,2-H-transfer, followed by cyclization through the recombination of a sulfur- and a carbon-centered radical. In contrast, the quantum yields for reaction in CH2Cl2 solutions are dependent on both oxygen concentration and on the concentration of trans-4,5-dihydroxy-1,2-dithiacyclohexane. The latter results are consistent with an intermolecular H-transfer between an initial dithiyl diradical and trans-4,5-dihydroxy-1,2-dithia-cyclohexane. Time-resolved laser flash photolysis studies indicate rapid product formation on the su...
Safe Surgical Dislocation of the Hip

Traditionally, surgical dislocation of the native hip has been discouraged because of the possible risk to the femoral head blood supply. Reinhold Ganz has clarified the proximal femoral vascular anatomy and has used this knowledge to develop a safe surgical dislocation technique for the hip. This new surgical technique has made possible safe and effective treatment of many intra-articular and periarticular conditions of the hip, many of which cause pain and arthrosis. In the hip, osteoarthritis very commonly is associated with well-recognized developmental deformities, classically from dysplasia, slipped epiphysis, or Perthes disease. Recent work has demonstrated that other much less well-recognized anatomic hip abnormalities, such as acetabular retroversion, acetabular overcoverage, and decreased femoral head-neck offset, are equally important generators of pathologic mechanics that frequently lead to arthrosis. Currently, the surgical dislocation technique plays a central role in treating hips with femoroacetabular impingement. Additionally, the surgical dislocation technique facilitates other femoral procedures such as flexion intertrochanteric osteotomy and femoral neck osteotomies. The surgical technique will be described in detail and the most recent surgical results will be discussed.
Development and characterization of a porcine model to study osteoclast differentiation and activity

Abstract The study of osteoclast differentiation, function, and fate has been hampered by the lack of nonavian, nonrodent models in which biochemical and molecular studies can be conducted. The present study was undertaken to determine if osteoclasts could be generated from porcine bone marrow cells. Bone marrow from the long bones of neonatal female pigs was enriched for mononuclear cells and cultured in the presence or absence of 1,25-(OH)2D3, rhIL-11, or PGE2. A confluent layer of stromal cells was observed after 4–8 days in culture and multinucleated giant cells formed after 6–10 days of culture. The multinucleated cells stained positively for tartrate-resistant acid phosphatase and formed resorption lacunae when exposed to bovine cortical bone slices. When examined by transmission electron microscopy, abundant mitochondria, perinuclear Golgi complexes, numerous variably sized vacuoles, prominent rough endoplasmic reticulum, and free polysomes were observed in the mutlinucleated cells. Stimulation of the in vitro generated osteoclasts with 10−8 mol/L salmon calcitonin resulted in a three to fivefold increase in cAMP production and in cell retraction. Although the osteoclasts formed in the presence or absence of 1,25-(OH)2D3 10–50-fold more osteoclasts were observed in the cultures treated with 1,25-(OH)2D3 in comparison to cultures without 1,25-(OH)2D3. Osteoclast differentiation was also stimulated by rhIL-11 and PGE2; although, the number of cells generated in 6–7 days was significantly less than the number obtained with 1,25-(OH)2D3 treatment. In addition, these multinucleated cells expressed high levels of Src kinase activity and responded to bafilomycin Al, an inhibitor of the vacuolar type H+-ATPase, treatment with a decrease in osteoclastic bone resorption. In summary, the porcine cells possess the major distinguishing characteristics of osteoclasts and provide an alternative mammalian model to study osteoclast differentiation and resorptive activity.
Tyrosine phosphorylation-dependent PI 3 kinase/Akt signal transduction regulates TGFβ-induced fibronectin expression in mesangial cells

TGFbeta stimulates expression of fibronectin in various cells, including mesangial cells. The mechanism by which TGFbeta exerts this effect is not fully understood. We investigated the involvement of tyrosine phosphorylation and the phosphatidylinositol (PI) 3 kinase/Akt signalling pathway in this process. TGFbeta increased tyrosine phosphorylation, resulting in activation of PI 3 kinase in mesangial cells. Inhibition of tyrosine phosphorylation blocked TGFbeta-induced fibronectin expression. Inhibition of PI 3 kinase activity also prevented fibronectin expression induced by TGFbeta. Furthermore, expression of constitutively active PI 3 kinase by adenovirus-mediated gene transfer increased fibronectin expression similar to TGFbeta. TGFbeta stimulated Akt serine threonine kinase in a tyrosine kinase- and PI 3 kinase-dependent manner. Inhibition of TGFbeta-induced Akt activity by adenovirus-mediated expression of a dominant-negative mutant of Akt abolished expression of fibronectin. Dominant-negative PI 3 kinase or dominant-negative Akt inhibited TGFbeta-induced fibronectin transcription. In contrast, and similarly to TGFbeta, expression of constitutively active PI 3 kinase or constitutively active Akt increased transcription of fibronectin, confirming a prominent role of these kinases in expression of fibronectin. These data provide the evidence that activation of TGFbeta receptor serine threonine kinase stimulates the PI 3 kinase/Akt pathway in a tyrosine phosphorylation-dependent manner and define a role for the same signal transduction pathway in TGFbeta-induced fibronectin expression.
Image-guided radiation therapy for prostate cancer: A computed tomography–based assessment of fiducial marker migration between placement and 7 days

Abstract Purpose This study was conducted to determine whether clinically significant fiducial marker migration occurs immediately after prostatic implantation. Methods and materials One hundred patients with transperineal (n = 39) or transrectal (n = 61) placement of 3 gold fiducial markers underwent computed tomography scans on day 0 (after placement) and day 7 (at radiation planning). Each marker was marked as a point of interest in a treatment planning system. An automated point-based algorithm was then used to coregister the day 0 and day 7 images by matching the markers through rigid translations and rotations. The mean distance between fiducial pairs ( d ¯ ) was recorded to assess the degree of seed migration. Prostate contours were delineated, and the day 0 prostate volumes were uniformly expanded by 1, 3, and 5 mm. The percentage of the day 7 prostate volume covered by each day 0 prostate with expansion was calculated to assess whether prostate contours, if performed on day 0, would adequately cover the prostate on day 7. Results The average d ¯ for all patients was 0.78 ± 0.45 mm; only 1 patient had d ¯ > 2 mm. Placement technique, hormonal therapy, prostate size, and marker distance from the capsule were not associated with d ¯ ( P > .05). The mean percentages of day 7 prostate volumes covered by the day 0 prostate plus 1, 3, and 5 mm were 98.3%, 99.8%, and 100%, respectively. With an expansion of 3 mm, 98% of men had >95% of day 0 volume covered; with an expansion of 5 mm, 100% of men had 100% of the day 0 volume covered. Conclusions There is minimal change in the relative positions of fiducial markers (average d ¯
Effects of Bradykinin and Autonomic Nervous System Inhibition on Systemic and Regional Hemodynamics in the Unanesthetized Rhesus Monkey

Studies were performed in unanesthetized monkeys to determine if bradykinin infusions reproduce the circulatory events of early endotoxemia. Kinin infusions before and during autononiic ganglionic blockade with trimethaphan were significantly correlated (P <0.05) with decreases in mean arterial pressure. Kinin infusion at 15-18, µg/kg min- produced 26 mm Hg fall in mean blood pressure at 3 min, due to fall in total peripheral resistance of 14 mm Hg/liter min-1. Heart rate rose 23 beats/min. After 10 minutes of infusion, peripheral resistance had returned to base line, blood pressure remained low due to fall in cardiac output of 0.53 liters/min (P <0.01). Ganglionic blockade prevented recovery of resistance. Plasma bradykinin levels at 3 and 10 minutes were 14 and 15 µg/ml, respectively. Regional and systemic hemodynamic effects of kinin (15-18 µg/kg min were determined in 10 monkeys. After 10 minutes of infusion, bradykinin produced systemic effects. Regional flow measurement (by radioactive microsphere t...
Smart Surfaces: Use of Electrokinetics for Selective Modulation of Biomolecular Affinities

With the aid of negative dielectrophoresis (nDEP) force in conjunction with shear force and at an optimal sodium hydroxide (NaOH) concentration we demonstrated a switch-like functionality to elute immuno-bound beads from the surface. At an optimal flow rate and NaOH concentration, nDEP turned on results in bead detachment, whereas when nDEP is off, the beads remain attached. This platform offers the potential for performing a bead-based multiplexed immunoassay where in a single channel various regions are immobilized with a different antibody, each targeting a different antigen. As a proof of concept we demonstrated the ability of nDEP to provide this switching behavior in a singleplex assay for the interactions that were in the same order of magnitude in strength as typical antibody-antigen interactions.
The perfluorocarbon fluoromethyloadamantane offers cerebral protection in a model of isovolemic hemodilution in rabbits.

Perfluorocarbons (PFCs) are considered promising cerebral protection agents because they could combine the beneficial effects of decreased blood viscosity with enhanced oxygen-carrying capacity and oxygen tissue delivery, but trials of PFCs as hemodilutants have been very limited. We evaluated fluoromethyloadamantane (FMA), a new perfluorocarbon compound, as an isovolemic hemodilutant and compared it with low-molecular-weight dextran 40 (D40) and a control group.Through a transorbital craniectomy, the internal carotid, anterior, and middle cerebral arteries were coagulated to create a cerebral infarction in anesthetized, mechanically ventilated rabbits. No other experimental procedure was performed in control animals. In the two other groups, hemodilution was commenced 30 minutes after the arterial occlusion with either D40 or FMA. Hemodynamic parameters and brain and systemic temperature were monitored throughout the experiments. All animals were killed 6 hours after the arterial occlusion.Hemodynamic an...
FIR filters for blind detection of CDMA signals

A new blind FIR filter receiver is proposed for the detection of DS-CDMA signals in unknown multi-user interference (MUI) and additive white Gaussian noise. The proposed receiver is motivated by the Wiener signal reconstruction theory and it is a very low complexity alternative to the minimum-output-energy (MOE) receiver. At only a minimal increase of the computational cost, the proposed detector outperforms significantly the conventional matched filter (MF) receiver. It also compares favorably to the decorrelating detector (with similar near-far resistance), despite the fact that the latter utilizes the assumed known MUI spreading codes. The novel characteristic of the proposed receiver is the incorporation of an auxiliary vector component that allows statistically optimal, adaptive steering of the filter with respect to the incoming DS-CDMA signal.
Discrimination and health outcomes.

Race and ethnicity are social constructs that have been used to divide people categorically into superior and inferior groups. Historically in the United States, racial groups categorized as inferi...
Toward 3D microfluidic structures fabricated with two-photon laser machining

We have developed a method to fabricate 31) microfluidic systems with two-photon polymerization in SU-8 photoresist. This approach will be an easy and accurate way to fabricate microfluidic systems simulating complex microstructures.
Analysis of Live Modeling Plus Prompting and Video Modeling for Teaching Imitation to Children with Autism

Previous researchers have demonstrated that training in imitation can significantly improve the learning capabilities of children diagnosed with autism spectrum disorder (ASD) and that children within this population show a preference for video presentations. Video-based instruction has been used to teach a variety of behaviors to individuals with ASD. However, only a small number of studies have examined the use of video modeling to teach initial imitation. Furthermore, there are limited and conflicting data on the effectiveness of a video modeling procedure that does not incorporate prompting when used to teach imitation to young children with ASD. Thus, the purpose of this study was to evaluate a video-modeling-alone procedure and a live-modeling-with-prompting procedure for teaching imitation to young children with ASD. The results suggest that the live modeling with prompting procedure was more effective, and implications related to this finding are discussed. Copyright © 2015 John Wiley & Sons, Ltd.
The pathophysiology of epileptic seizures: a primer for pediatricians.

1. Carl E. Stafstrom, MD, PhD* 1. 2. *Associate Professor of Pediatrics and Neurology, Tufts University School of Medicine; Director, Epilepsy Center for Children, The Floating Hospital for Children at New England Medical Center, Boston, MA. Seizures are one of the most common neurologic disorders affecting children. As many as 5% of children experience a seizure during childhood. Although many epilepsies, especially refractory ones, are managed by specialists in pediatric neurology or epilepsy, general pediatricians often are called upon to manage children who have both acute and chronic seizures. Therefore, it is important to understand some of the basic pathophysiologic mechanisms underlying epileptic seizures. This understanding will allow the physician to choose the most appropriate medication for the given seizure type and clinical setting. Seizures can be a particular challenge to treat. Fortunately, in addition to the armamentarium of anticonvulsant agents previously available, a profusion of new antiepileptic drugs (AEDs) has appeared in the past 5 years. Some of these drugs are designed to address specific pathophysiologic defects in the sequence of events leading to the generation or spread of seizures. The purpose of this article is to review the principles of cellular neurophysiology as a foundation for understanding how normal neuronal function goes awry in epilepsy. First, normal synaptic transmission and neuronal firing are summarized. Next, the pathophysiology of acute and chronic seizures is discussed. Finally, the mechanisms by which AEDs control the hyperexcitability that underlies epilepsy are considered. ### DEFINITIONS A seizure is a temporary disruption of brain function due to the hypersynchronous, excessive discharge of cortical neurons. Sometimes the term epileptic seizure is used to distinguish from a nonepileptic seizure such as a pseudoseizure, which is not caused by hypersynchronous firing of neurons. The clinical manifestations of a seizure depend on the specific region and extent of brain involvement and may include an alteration in motor function, sensation, alertness, perception, autonomic function, or all of these. Any person can experience a seizure in the appropriate clinical setting (eg, meningitis, hypoglycemia, toxin ingestion), attesting to the …
Formation of calcium carbonate particles by direct contact of Ca(OH)2 powders with supercritical CO2

A novel method to obtain a high conversion of Ca(OH)2 powder to CaCO3 is reported. The method uses supercritical CO2 containing water that is passed over the dry Ca(OH)2 powder. Conversions greater than 98% are obtained. The dominant crystal structure is calcite. The process has the advantages of the conventional solution based process in terms of high conversion and the advantages of a gas–solid based process in that dry, non-agglomerated particles are obtained by simple venting of the solvent.
The politics of soft credit in post‐Soviet Russia

AN ESSENTIAL ELEMENT of economic reform in post-communist states is to create efficient capital markets. In developed capitalist orders, such markets are 'at the centre of the "brain" of the entire economic system'.' Banks, stock and bond brokers, mutual funds, venture capital firms and other financial institutions compete to attract investment resources and to direct them to uses where expected profits are highest. Through their actions, Pareto superior allocations are achieved and growth rates rise.2 Soviet-type economies were 'redistributive systems'.3 Capital markets, efficient or otherwise, did not exist. Instead, financial resources were allocated and continually redistributed through a combination of planning, informal bargaining and malfeasance. Investment plans were adopted centrally and disaggregated by lower-level planning bodies and ministries. They were financed almost entirely through budgetary transfers. Short-term credit for working capital was extended to enterprises by the state bank within limits established by the credit plan. In turn, almost all enterprise profits were remitted to the budget for future reallocation.4 In practice, however, central priorities were reshaped from below. Agents concealed and distorted information, reinterpreted directives in the implementation, and sometimes simply disobeyed principals higher up in the hierarchy. Plan assignments were repeatedly renegotiated, sometimes as late as in December of the planned year.5 All the parameters of financial redistribution-investment capital, credit limits, prices-were subject to bureaucratic lobbying, rendering budget constraints 'soft'.6 An 'administrative market' of bartered favours evolved, along with a 'shadow economy' of diverted goods and resources.7 Since 1987 the Soviet-and then the Russian-banking system has undergone reforms.8 The monobank system was first replaced by a two-tiered structure of a central bank and five specialised banks.9 Then the specialised banks were commercialised and transformed into joint stock companies, with regional and local branches often becoming independent. With the dissolution of the Soviet Union in December 1991, the State Bank divided into 15 central banks. In parallel, about 1700 private
Excess Costs Associated With Complications and Prolonged Length of Stay After Congenital Heart Surgery

Background While there is an increasing emphasis on both optimizing quality of care and reducing health care costs, there are limited data regarding how to best achieve these goals for common and resource-intense conditions such as congenital heart disease. We evaluated excess costs associated with complications and prolonged length of stay (LOS) after congenital heart surgery in a large multicenter cohort. Methods Clinical data from The Society of Thoracic Surgeons Database were linked to estimated costs from the Pediatric Health Information Systems Database (2006 to 2010). Excess cost per case associated with complications and prolonged LOS was modeled for 9 operations of varying complexity adjusting for patient baseline characteristics. Results Of 12,718 included operations (27 centers), average excess cost per case in those with any complication (versus none) was $56,584 (+$132,483 for major complications). The 5 highest cost complications were tracheostomy, mechanical circulatory support, respiratory complications, renal failure, and unplanned reoperation or reintervention (ranging from $57,137 to $179,350). Patients with an additional day of LOS above the median had an average excess cost per case of $19,273 (+$40,688 for LOS 4 to 7 days above median). Potential cost savings in the study cohort achievable through reducing major complications (by 10%) and LOS (by 1 to 3 days) were greatest for the Norwood operation ($7,944,128 and $3,929,351, respectively) and several other commonly performed operations of more moderate complexity. Conclusions Complications and prolonged LOS after congenital heart surgery are associated with significant costs. Initiatives able to achieve even modest reductions in these morbidities may lead to both improved outcomes and cost savings across both moderate and high complexity operations.
Selective and low temperature synthesis of polycrystalline diamond

Polycrystalline diamond thin films have been deposited on single-crystal silicon substrates at low temperatures (not above 600 C) using a mixture of hydrogen and methane gases by high-pressure microwave plasma-assisted chemical vapor deposition. Low-temperature deposition has been achieved by cooling the substrate holder with nitrogen gas. For deposition at reduced substrate temperature, it has been found that nucleation of diamond will not occur unless the methane/hydrogen ratio is increased significantly from its value at higher substrate temperature. Selective deposition of polycrystalline diamond thin films has been achieved at 600 C. Decrease in the diamond particle size and growth rate and an increase in surface smoothness have been observed with decreasing substrate temperature during the growth of thin films. As-deposited films are identified by Raman spectroscopy, and the morphology is analyzed by scanning electron microscopy.
Manufacturing of 3-D Microstructures Using Novel Upsams Process for Mems Applications

This paper introduces a new microfabrication technique, Ultraprecision Manufacturing of Self-Assembled Micro-Systems (UPSAMS), which combines ultraprecision micromachining (milling/turning/drilling/grinding) with sacrificial/structural multi-layer manufacturing processes to produce self-assembled, 3-D microsystems and associated mesoscale interfaces from a variety of materials for MEMS applications. With this process, a new class of microsystems can be developed that is highly three dimensional, precisely machined, and automatically assembled.
A Critique of U.S.-Mexico Border Health Interventions

The effectiveness of recent health interventions along the U.S.-Mexico border is examined to identify gaps and deficiencies in the approaches to conducting program interventions. This chapter presents, discusses, and illustrates a systems approach as an appropriate methodology for refining our state of knowledge regarding successful, replicable intervention programs that are culturally meaningful, generalizable, and cost-effective. The resolution of data problems is key to developing plans for evaluation research and sharing of information about new and on-going public health interventions.
Hydrogen sulfide: role in ion channel and transporter modulation in the eye

Hydrogen sulfide (H2S), a colorless gas with a characteristic smell of rotten eggs, has been portrayed for decades as a toxic environmental pollutant. Since evidence of its basal production in mammalian tissues a decade ago, H2S has attracted substantial interest as a potential inorganic gaseous mediator with biological importance in cellular functions. Current research suggests that, next to its counterparts nitric oxide and carbon monoxide, H2S is an important multifunctional signaling molecule with pivotal regulatory roles in various physiological and pathophysiological processes as diverse as learning and memory, modulation of synaptic activities, cell survival, inflammation and maintenance of vascular tone in the central nervous and cardiovascular systems. In contrast, there are few reports of a regulatory role of H2S in the eye. Accumulating reports on the pharmacological role of H2S in ocular tissues indicate the existence of a functional trans-sulfuration pathway and a potential physiological role for H2S as a gaseous neuromodulator in the eye. Thus, understanding the role of H2S in vision-related processes is imperative to our expanding knowledge of this molecule as a gaseous mediator in ocular tissues. This review aims to provide a comprehensive and current understanding of the potential role of H2S as a signaling molecule in the eye. This objective is achieved by discussing the involvement of H2S in the regulation of (1) ion channels such as calcium (L-type, T-type and intracellular stores), potassium (KATP and small conductance channels) and chloride channels, (2) glutamate transporters such as EAAT1/GLAST and the L-cystine/glutamate antiporter. The role of H2S as an important mediator in cellular functions and physiological processes that are triggered by its interaction with ion channels/transporters in the eye will also be discussed.
Do infants understand simple arithmetic? A replication of Wynn (1992) ☆

Abstract Numerical competence in 5-month-old infants is investigated using a violation-of-expectation paradigm. An experiment is reported which replicates the findings of Wynn (1992). In additional conditions, 5-month-olds are shown to be sensitive to impossible outcomes following addition or subtraction operations on small sets of objects, regardless of identity changes. Results support Wynn's interpretation that infants' responses are based on arithmetical ability. An alternative explanation, that infants' responses are based on their knowledge of the principles of physical object behavior, is also discussed.
p21 stability: Linking chaperones to a cell cycle checkpoint

Progression through the cell cycle is regulated by numerous proteins, one of which is the cyclin-dependent kinase inhibitor, p21. A new study identifies a novel protein complex that stabilizes p21. The stability of this complex is critical in effecting the p53-mediated cell cycle checkpoint.
Why Oil Importers Diversify their Import Sources Politically? Evidence from U.S. Firm-Level Data *

International politics affects oil trade. But why? We construct a firm-level dataset for all U.S. oil-importing companies over 1986-2008 to examine what kinds of firms are more responsive to change in “political distance” between the U.S. and her trading partners, measured by divergence in their UN General Assembly voting patterns. Consistent with previous macro evidence, we first show that individual firms diversify their oil imports politically, even after controlling for unobserved firm heterogeneity. We conjecture that the political pattern of oil imports from these individual firms is driven by hold-up risks, because oil trade is often associated with backward vertical FDI. To test this hold-up risk hypothesis, we investigate heterogeneity in responses by matching transaction-level import data with firm-level worldwide reserves. Our results show that long-run oil import decisions are indeed more elastic for firms with oil reserves overseas than those without, although the reverse is true in the short run. We interpret this empirical regularity as that while firms trade in the spot market can adjust their imports immediately, vertically-integrated firms with investment overseas tend to commit to term contracts in the short run even though they are more responsive to changes in international politics in the long run.
Nucleic acid oxidation: an early feature of Alzheimer's disease

Studies of oxidative damage during the progression of Alzheimer's disease (AD) suggest its central role in disease pathogenesis. To investigate levels of nucleic acid oxidation in both early and late stages of AD, levels of multiple base adducts were quantified in nuclear and mitochondrial DNA from the superior and middle temporal gyri (SMTG), inferior parietal lobule (IPL), and cerebellum (CER) of age-matched normal control subjects, subjects with mild cognitive impairment, preclinical AD, late-stage AD, and non-AD neurological disorders (diseased control; DC) using gas chromatography/mass spectrometry. Median levels of multiple DNA adducts in nuclear and mitochondrial DNA were significantly (p ≤ 0.05) elevated in the SMTG, IPL, and CER in multiple stages of AD and in DC subjects. Elevated levels of fapyguanine and fapyadenine in mitochondrial DNA suggest a hypoxic environment early in the progression of AD and in DC subjects. Overall, these data suggest that oxidative damage is an early event not only in the pathogenesis of AD but is also present in neurodegenerative diseases in general. Levels of oxidized nucleic acids in nDNA and mtDNA were found to be significantly elevated in mild cognitive impairment (MCI), preclinical Alzheimer's disease (PCAD), late-stage AD (LAD), and a pooled diseased control group (DC) of frontotemporal dementia (FTD) and dementia with Lewy bodies (DLB) subjects compared to normal control (NC) subjects. Nucleic acid oxidation peaked early in disease progression and remained elevated. The study suggests nucleic acid oxidation is a general event in neurodegeneration.
Effect of Feed and Water Deprivation on Chickens, Turkeys, and Laboratory Mammals

Abstract STARVATION has always been among the greatest calamities of civilized man and his domesticated animals. Billions of individuals have starved since early times, but it was not until this generation that human starvation was studied in an intensified manner (Keys et al., 1950). It appears that similar studies have not been made on poultry or other domesticated animals. In an historical review of the veterinary profession, Smithcors (1963) has pointed out that many of the livestock disease problems of the 19th century were a result of starvation and that the fictitious disease “hollow horn” was usually due to “hollow belly.” Dale et al. (1954) studied the effect of starvation on the acid-base balance of bovine blood plasma. Weanling pigs were deprived of feed for periods up to 28 days, by Hanawalt and Sampson (1947) in acute hypoglycemia studies. Marion et al. (1956) reported increased mortality in day-old chicks when not…
Magnetotunneling absorption in double quantum wells

Tunneling absorption is calculated in weakly-coupled n-type asymmetric double quantum wells in an in-plane magnetic field using a linear response theory. Tunneling absorption of photons occurs between the ground sublevels of the quantum wells. We show that the absorption threshold, the resonance energy of absorption, and the linewidth depend sensitively on the magnetic field and the temperature.
Equivalence Between Two Flavours of Oblivious Transfers

The concept of oblivious transfer (O.T.) that was induced by Halpern and Rabin m] turned out to be a very useful tool in designing cryptographic protocols. The related notion of “one-out-of-two oblivious transfer” was proposed by Even, Goldreich and Lempel in [EGL] together with some applications. Some more applications of this protocol can be found in recent papers [BCR], [GMWj. So far, the two notions where believed to be closely related but not known to be equivalent. This paper presents a proof that these two notions are computationally equivalent.
Shape analysis of odontocete mandibles: Functional and evolutionary implications

Odontocete mandibles serve multiple functions, including feeding and hearing. We consider that these two major functions have their primary influence in different parts of the mandibles: the anterior feeding component and the posterior sound reception component, though these divisions are not mutually exclusive. One hypothesis is that sound enters the hearing apparatus via the pan bone of the posterior mandibles (Norris, Evolution and Environment,1968, pp 297–324). Another viewpoint, based on finite element models, suggests that sound enters primarily through the gular region and the opening created by the absent medial lamina of the posterior mandibles. This unambiguous link between form and function has catalyzed this study, which uses Geometric Morphometrics to quantify mandibular shape across all major lineages of Odontoceti. The majority of shape variation was found in the anterior (feeding) region: Jaw Flare (45.0%) and Symphysis Elongation (35.5%). Shape differences in the mandibular foramen, within the posterior (sound reception) region, also accounted for a small portion of the total variation (10.9%). The mandibles are an integral component of the sound reception apparatus in toothed whales and the geometry of the mandibular foramen likely plays a role in hearing. Furthermore, model goodness-of-fit tests indicate that mandibular foramina shapes, which appear conserved, evolved under a selective regime, possibly driven by sound reception requirements across Odontoceti. J. Morphol. © 2012 Wiley Periodicals, Inc.
Evaluating Forecasters' Rules of Thumb: A Study of d(prog)/dt

Abstract Forecasters often develop rules of thumb for adjusting model guidance. Ideally, before use, these rules of thumb should be validated through a careful comparison of model forecasts and observations over a large sample. Practically, such evaluation studies are difficult to perform because forecast models are continually being changed, and a hypothesized rule of thumb may only be applicable to a particular forecast model configuration. A particular rule of thumb was examined here: dprog/dt. Given a set of lagged forecasts from the same model all verifying at the same time, this rule of thumb suggests that if the forecasts show a trend, this trend is more likely than not to continue and thus provide useful information for correcting the most recent forecast. Forecasters may also note the amount of continuity of forecasts to estimate the magnitude of the error in the most recent forecast. Statistical evaluation of this rule of thumb was made possible here using a dataset of forecasts from a “frozen” ...
Pain Assessment and Management in the Critically Ill: Wizardry or Science?

Assessment and management of patients’ pain across practice settings have recently received the increased attention of providers, patients, patients’ families, and regulatory agencies. Scientific advances in understanding pain mechanisms, multidimensional methods of pain assessment, and analgesic pharmacology have aided in the improvement of pain management practices. However, pain assessment and management for critical care patients, especially those with communication barriers, continue to present challenges to clinicians and researchers. The state of nursing science of pain in critically ill patients, including development and testing of pain assessment methods and clinical trials of pharmacological interventions, is described. Special emphasis is placed on results from the Thunder Project II, a major multisite investigation of procedural pain. (American Journal of Critical Care. 2003;12:310-316)
Heart Failure: A Global Pandemic and Not Just a Disease of the West.

Heart Failure Clinics - Sous presse. Epreuves corrigees par l'auteur. Disponible en ligne depuis le mardi 25 aout 2015
Impact of ISO 9001 certification on firms financial operating performance

Purpose – The purpose of this paper is to investigate the impact of ISO 9001 certification on US firms’ financial operating performance for a period of five years including one-year prior to certification, year of certification, and three fiscal years after certification. Design/methodology/approach – The paper is based on an examination of a sample of 397 firms that had received ISO 9001 certification from 1991 to 2002. Certified-firm, non-certified-firm, and matched-control-firm operating performances were examined over the same period based on the ratio of pre-tax operating income to total assets (EBITA/TA). Wilcoxon signed-rank test was used to test for significant differences in operating performance among the certified, non-certified, and matched-control firms. Findings – The paper concludes that there was significant improvement performance from prior year to year of certification. The certified firms performed better than the non-certified firms. The certified firms also performed better than the ...
The turnover of collagen in fibroblast cultures.

Collagen turnover was studied in mouse fibroblast cultures (3T6) by radioactive labelling and compartmental analyses. The incorporation of [14C]proline into protein during continuous labelling rapidly reached a maximum value which was directly proportional to the medium specific activity. Radioactivity appeared more slowly in hydroxyproline, and gradually accumulated as cultures became enriched in collagen and its breakdown products. In relation to total new protein synthesis, the proportional synthesis of collagen, as measured by the formation of [14C]hydroxyproline, was less in logarithmically growing than in stationary-phase cultures, and little was deposited in the cell layer. Newly synthesized hydroxyproline was consistently present in all growth media. In stationary-phase cultures, media contained as much as 60% of the total [14C]hydroxyproline in a form soluble in 0.5 M perchloric acid. Gel filtration chromatography confirmed that this was predominantly free hydroxyproline, only 30% appearing in small peptides whose degree of hydroxylation suggested their origin from larger collagen molecules. This acid-soluble compartment was taken as a convenient index of collagenolysis, which proved to be significant in both growth states, but was proportionately more important throughout logarithmic growth. Reincubation of prelabelled cultures in fresh medium containing an excess of non-radioactive proline (‘chase’ medium) was followed by the degradative loss of labelled cell layer protein. The released radioactivity could be quantitatively recovered in the growth medium for periods up to 6 days; the rate of its appearance was little influenced by the frequency of feeding. Despite extensive dilution of the proline precursor-pool specific activity, synthesis of [14C]hydroxyproline continued in all chase cultures. The increment appeared largely as collagen breakdown products in the growth medium, and probably arose from 2 principal sources: (1) recently deposited collagen, and (2) the hydroxylation of peptidyl-[14C]proline residues in protocollagen. The balance between these contributions seemed to be dependent upon the extent to which ‘ageing’ of the cell layer collagen had occurred prior to initiating the chase. Radioactive hydroxyproline was rapidly lost from briefly prelabelled cell layers, but was well retained in a macromolecular form when the initial labelling period was sufficiently prolonged. It is proposed that the endogenous collagen-degradative apparatus attacks both young collagen and its polypeptide precursor, but that as the lability of the former substrate rapidly declines, enzyme activity continues to operate on protocollagen to yield [14C]hydroxyproline-containing breakdown products which gradually diminish as the latter substrate pool is exhausted.
A Proposal to Limit the Flow of Human Resources into Farming

T WO major types of agricultural policies have been advocated in the past. The first has been aimed at increasing total (and hence per capita) farm income. Emphasis has been given to increasing production efficiency, supporting prices above the level of a free market price, and subsidizing exports. The second basic type of policy, proposed but never specifically enacted into legislation, focuses on inducing the movement of people off the farm. Direct payments for moving, plus support while the head of the household learns a new trade, have been suggested. Also proposed have been the creation of better off-farm employment opportunities and the improvement of information on the availability of off-farm jobs. These have been the two general directions of past agricultural policy proposals-raising total farm income and increasing off-farm mobility. I would like to suggest a third direction that agricultural policy might take, perhaps in conjunction with one or both of the above approaches: namely, limiting the flow of human resources into farming. Such a policy would have a result similar to that of the second policy mentioned above, that is, dividing total agricultural income among fewer individuals. However, from the standpoint of implementation, it may have several advantages. A basic assumption underlying the policy of inducing off-farm migration has been that those farmers with the lowest incomes would be highly motivated to move in an effort to better their lot. However, the farmers making the least income are on the average older, and it is difficult to persuade them to move away from an environment to which they have become accustomed. Further, and perhaps more significant, those making the least income are also likely to be the least capable; hence, they would have greater difficulty in learning a new trade. The policy proposed herein of slowing the flow of people into farming
Lungs and Breathing

The discussion of the human respiratory system begins with a study of lung structure. This is followed by analyzing the microphysics of the lung alveoli and the macrophysics of the lung and the breathing process. Breathing under unusual conditions is also discussed, including breathing with a diseased lung and at high elevations.
Phase Equilibria and Microstructural Evolution in Ternary Co-Al-W Between 750 and 1100 °C

Phase equilibria between 750 and 1100 °C in the Co-rich portion of the Co-Al-W ternary system are investigated via isothermal annealing of five ternary alloy compositions. At temperatures of 900 °C and below, the phase diagram is dominated by a three-phase tie-triangle between γ, D019, and B2. The 1000 °C section contains two three-phase tie-triangles, γ + D019 + μ and γ + B2 + μ; while only one, γ + B2 + μ, exists at 1100 °C. Results at 950 °C suggest that it is possible that γ′ is in equilibrium, with four out of five compositions exhibiting microstructures supporting its thermodynamic stability, and the fifth composition containing only a very small amount of a fourth phase. However, if true, the temperature range of γ′ stability would be quite small, and it is more likely that the kinetics of γ′ dissolution are the cause of its persistence at 950 °C. At 850 °C, γ′ is observed to dissolve more rapidly than at 900 °C where dissolution exceeds 8000 h. A time-temperature-transformation diagram constructed from the combined results exhibits a classic nose-shape indicative of the tradeoff between thermodynamics and kinetics. This further supports a small driving force as the reason for the persistence of γ′ in the microstructures of Co-Al-W alloys at 900 and 950 °C. The measured equilibrium phase compositions and five corresponding isothermal sections of the phase diagram will provide essential data for constructing a new thermodynamic description of ternary Co-Al-W.
Mid-Infrared Semiconductor Lasers

Considerable progress has been made in mid-IR semiconductor lasers in terms of maximum operating temperature and output power. Antimonide-based type-I quantum-well lasers have exhibited cw operation at 2.0 μm up to 400 K, at 2.7μm to 234 K, at 3.5μm to 175 K, and at 3.9 μm to 128 K. 4-μm lasers pumped by 1-μm diode laser arrays have yielded peak power of 2 W and average power of 240 mW at 92 K. Diode lasers utilizing type-II transitions have exhibited pulsed operation between 2.8 and 4.3 μm, with maximum operating temperature of 255 K at 3.2 μm. Type-II lasers pumped by a high-power Ho:YAG laser have operated pulsed up to 350 K at 3.2 μm and 285 K at 4.1 μm. Quantum cascade lasers emitting at - 5 μm or - 8 μm have operated pulsed up to 320 K and cw to 140 K.
Overview of blood purification in uremia.

Today, management of irreversible renal failure is based primarily on maintenance hemodialysis and renal transplantation with a growing minority of patients treated by peritoneal dialysis. With reg...
Analysis of Testosterone in Serum Using Mass Spectrometry

For either gas chromatography mass spectrometry (GC-MS) or liquid chromatography tandem mass spectrometry (LC-MS-MS) methods, the first step in the analysis is to add a deuterium-labeled internal standard such as testosterone-16,16,17-d(3). Testosterone in the sample is then isolated by liquid-liquid extraction and the extract is dried under a stream of nitrogen. For the GC-MS method we describe; the residue is transformed to the pentafluorobenzyl/trimethylsilyl derivative and is injected into the GC-MS, separated on a dimethypolysiloxane column, and ionized using electron capture negative chemical ionization (ECNCI). Quantification of testosterone in the samples is by selected ion monitoring, measuring peak ratios of testosterone relative to the deuterium-labeled internal standard. For the LC-MS-MS analysis of testosterone, the sample extract is reconstituted in mobile phase, injected on a C18 column, and quantified using multiple reaction monitoring of testosterone relative to the internal standard. There are no interferences from common steroids found in human serum. For both methods the run-to-run precision and accuracy is generally less than 6% and the methods are linear from 5 to 2000 ng/dL.