cssi/SciSciGPT-SciSciNet huggingface dataset:
Intracameral antibiotic agents for endophthalmitis prophylaxis: a pharmacokinetic model.

Abstract Purpose To assess in vitro whether intracameral antibiotic agents are plausibly effective prophylaxis against Staphylococcus aureus endophthalmitis. Setting University research laboratory. Methods Staphylococcus aureus was cultured for 8 hours with vancomycin (50 μg/mL) or piperacillin/tazobactam (512/64 μg/mL). Without reducing the bacterial counts, the antibiotic concentration was halved every 2 hours to simulate the half-life of antibiotic agents in the anterior chamber. The number of colony forming units (CFU)/mL was measured at 0, 2, 4, 6, and 8 hours. Results Vancomycin inhibited the growth of methicillin-resistant S aureus such that the CFU/mL was 1000 times higher in the control group after 8 hours. Piperacillin/tazobactam nearly eliminated 1 oxacillin-susceptible strain and reduced the CFU/mL of another strain 1000-fold. Conclusions Intracameral vancomycin may inhibit the growth of S aureus in the anterior chamber after surgery. Inhibiting the growth could increase the chances that the eye's innate defenses would eliminate the bacterial contamination that could cause endophthalmitis.
Nuclear magnetic resonance spectroscopy. Concentration dependence of the T1 relaxation time for 13C in dioxane-D2O. Some experimental problems with T1 measurements

The ^(13)C T_1 relaxation times determined for dioxane-D_2O solutions by the progressive saturation method have been found to range from 5 sec for 1:1 (v/v) dioxane-D_2O to 12 sec for neat dioxane. The concentration dependence roughly parallels the inverse of the viscosity and is likely to be associated with changes in correlation times because of hydrogen bonding. A 2:1 (v/v) dioxane-D_2O mixture with a T_1 of 6.2 ± 0.6 sec at 30°C has been found to be a useful standard for checking instrument performance in the determination of T_1 values. A number of experimental problems associated with measuring T_1 are discussed.
Testing Moran's theorem in an agroecosystem

Th e abundance and reproductive eff ort of populations frequently fl uctuate across space and time, a phenomenon known as spatial synchrony. Knowledge of the causes of this behavior underlies the ability to manage species, protect the health of humans and the environment, and increase agricultural sustainability. We used an agroecosystem to test Moran ’ s theorem – spatial synchrony results from environmental entrainment. Th e controlled conditions of the agroecosystem allowed us to create a highly correlated environment while negating the eff ects of the alternative hypotheses: dispersal and trophic interactions. Under such conditions, synchrony of fruit production by 4288 trees was high over six years in a 32.5 ha pistachio orchard and occurred at similar temporal frequency as weather patterns demonstrating the Moran eff ect. Th e spatial synchrony of fruit production was less than the presumed synchrony of the environment supporting research from microcosms and observational studies showing the Moran eff ect is degraded by local mechanisms. Indeed even under the homogeneous environment of this system, synchrony declined signifi cantly with distance among trees. We present evidence suggesting that the correlation of the local environment aff ects intrinsic dynamics to cause these patterns. Our fi ndings demonstrate that the Moran eff ect is, at minimum, partially responsible for the synchronous fruit production in this system. Agroecosystems are often overlooked in basic ecological research; this experiment provides an example of their comparative advantages for the study of some ecological questions.
Exercising budgetary control in automated production environments

Abstract. This study examines budgetary control in automated production environments. It is argued that the relative insignificance of direct labor costs, together with the greater degree of integration of service and production departments in automated production environments, restrict the degree of freedom that normally exists in the design of an appropriate budgetary control system. The paper argues for a more integrated approach, and demonstrates that the reciprocal allocation method, linked with the dual allocation approach, has the properties necessary for an appropriate budgetary control system for automated production environments. The paper extends the current literature by demonstrating some properties of the reciprocal method hitherto unexplored. Resume. L'auteur examine le controle budgetaire dans le contexte de la fabrication automatisee. Il soutient que le peu d'importance relative des couts de main-d' œuvre directe, associe au degre plus grand d'integration des services auxiliaires et du service de fabrication dans le contexte de la fabrication automatisee, restreint la liberte qui existerait normalement dans la conception d'un systeme de controle budgetaire approprie. L'auteur favorise une methode plus integree et demontre que la methode de repartition reciproque, liee a la methode de double repartition, presente les proprietes necessaires pour que le systeme de controle budgetaire soit approprie au contexte de la fabrication automatisee. Dans le prolongement des publications courantes, l'auteur fait etat de certaines proprietes de la methode reciproque jusqu'ici inexplorees.
Zero-quantum filter offering single-shot lipid suppression and simultaneous detection of lactate, choline, and creatine resonances.

A zero-quantum (ZQ) filter offering single-shot lipid suppression and providing for simultaneous detection of the lactate methyl doublet (1.3 ppm) and nonoverlapping singlets including choline (Cho, 3.2 ppm) and creatine (Cr, 3.0 ppm) is described. Filtering is provided by soft mixing and reading pulses (RFmix, RFrd) that are selective for the lactate methine quartet (4.1 ppm), Cho, and Cr resonances but exclude the 1.3 ppm lactate component and overlapping lipids. Surrounding RFmix and RFrd are magnetic field gradient pulses of equal magnitude but opposite signs to enable the rephasing of the zero-quantum lactate coherence and the creation of a stimulated echo for singlets within the pulse passbands. The sequence is designed to retain half the original lactate and singlet signal intensities. Theoretical predictions were confirmed experimentally at 1.5T using phantom acquisitions. The lipid suppression factor was measured to be over 103. Magn Reson Med 46:1233–1237, 2001. © 2001 Wiley-Liss, Inc.
Anti-oxidant enzymes in fetal guinea pig brain during development and the effect of maternal hypoxia

Abstract The development of the anti-oxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase was studied in the fetal guinea pig brain at 30, 35, 40, 45, 50, 55, and 60 days of gestation. The activities of these enzymes remained constant during 30–45 days of gestation and increased significantly during the 45–60 day period, with the exception of superoxide dismutase, which remained unchanged throughout the gestational period. The enzyme activities in fetal brain tissue at every gestational age were unaffected by maternal hypoxia (inspired oxygen, 7% for 40 min). The concurrent development of glucose-6-phosphate dehydrogenase, glutathione reductase, and glutathione peroxidase during 45–60 days of gestation indicates an increased ability of the fetal brain to detoxify lipid peroxidation products by reinforcing the glutathione system. The results of this study indicate that the anti-oxidant enzymatic defense mechanisms in the guinea pig brain are fairly mature at birth. However, these mechanisms are underdeveloped during the early stages of gestation and, therefore, during this period the brain might be at potential risk for lipid peroxidative damage under conditions leading to increased formation of oxygen free radicals.
DSP-enabled coherent optical communications

Digital signal processing techniques used in conjunction with phase-diversity coherent optical receivers are presented in this paper. These techniques enable coherent detection and mitigation of optical impairments introduced in transmission. The main advantage of this approach is that the optical impairments can be handled in the digital domain instead of analog or optical domains, thus reducing various hardware requirements (e.g. dispersion compensating fibers). Dispersion compensation and carrier phase estimation techniques are discussed in detail.
Sodium lactate influences myoglobin redox stability in vitro.

Injection-enhancement of beef with lactate improves color stability; however, the mechanism is unclear. Thus, our objectives were to assess the effects of sodium lactate on equine myoglobin redox stability in vitro. Oxymyoglobin at pH 5.6 (50 mM sodium citrate) and pH 7.4 (50 mM sodium phosphate) was incubated at 4 °C with lactate (0, 5, 10, 100, or 200 mM) and myoglobin redox form was determined using absorbance spectra. Metmyoglobin formation at pH 5.6 and 7.4 was significantly (P < 0.05) decreased by lactate at concentrations of 100 and 200 mM. In general, increasing lactate concentration from 100 to 200 mM increased (P < 0.05) oxymyoglobin redox stability. This effect of lactate on myoglobin redox stability could be partially responsible for the improved color stability associated with lactate injection-enhanced beef products. Further work should determine the effect of lactate on beef myoglobin.
Spinodal decomposition in mixtures containing nematogens

Abstract A general stability criterion is presented for mixtures containing nematic liquid crystals. Conditions for absolute phase instability are found and represent a generalization of the usual spinodal concept. Physically, these conditions represent instabilities with respect to variations in the systems composition, degree of molecular ordering or some combination thereof. An example calculation corresponding to a liquid-crystalline polymer is presented. This calculation is based upon a well known lattice model which includes energetics that are dependent upon molecular orientation. Spinodal decomposition has profound effects on the morphology of a system which undergoes phase separation. Recent experimental and theoretical studies have attempted to explore these consequences in liquid-crystalline systems. None gives a rigorous definition of what is meant by spinodal in a mixture with orientational degrees of freedom; the material presented here clarifies this issue.
Oxytocin and its receptor in pregnancy and parturition: Current concepts and clinical implications

Objective : To present our current understanding of oxytocin and its receptors during pregnancy and parturition and their potential clinical applications. Data Sources : A MEDLINE search was conducted for pertinent articles from 1966 to October 1996 related to oxytocin and its receptor and their clinical implications during pregnancy and parturition. Review articles, book chapters, and published trials were also searched. Methods of Study Selection : Only references in English that were deemed relevant were used. When possible, human data and sometimes animal data pertinent to understanding the interaction of oxytocin and its receptors were selected. Tabulation, Integration, and Results : Oxytocin is synthesized in the hypothalamus and in many reproductive tissues during pregnancy, whereas the receptors are synthesized in reproductive tissues. The genes for oxytocin and its receptors are on chromosomes 20 and 3, respectively. Oxytocin and its receptors are regulated by sex steroids and by oxytocin itself. The paracrine and autocrine mechanisms regulating oxytocin and its receptor within the fetoplacentaluterine unit are central to the control of uterine contractions and parturition. Such current understanding provides the basis for appropriate oxytocin regimens to induce or augment labor, to inhibit preterm labor by blockade of oxytocin receptors, and to achieve cervical ripening. Conclusion : Advances in our knowledge of oxytocin and its receptor have provided rational and sound principles for current concepts about their role in parturition, the appropriate use of oxytocin to stimulate the pregnant uterus or ripen the cervix, and the use of oxytocin antagonist to inhibit uterine contractions and preterm labor.
Heterogeneity in the composition of marijuana seized in California

Background Marijuana contains multiple cannabinoids. Most attention is given to delta-9-tetrahydrocannabinol (THC) which produces euphoria and in some cases anxiety and panic reactions. Research suggests that another cannabinoid, cannabidiol (CBD), may offset some of these effects. Thus, there is growing interest in the health consequences of the THC to CBD ratio for marijuana.
Forearc response to subduction of the Cocos Ridge, Panama-Costa Rica

Stratigraphic, paleontologic, and structural data from two Panama-Costa Rica forearc peninsulas located landward of the aseismic Cocos Ridge along the southernmost Middle America Trench document rapid Pliocene subsidence and basin infilling followed by Quaternary deformation and uplift. On the Burica Peninsula, an approximately 3,000-m-thick, Pliocene-Pleistocene clastic sedimentary sequence, characterized by fine-grained turbidite deposits and volumetrically minor coarser-grained channel-fill, slump, and debris-flow deposits, bears depth-diagnostic foraminifera that document rapid Pliocene subsidence and deposition on a south-dipping paleoslope. New paleobathymetric and age estimates from foraminifera in these rocks indicate shallowing of depositional paleodepths from 2,000+ to 1,200 m during the late Pliocene. Present-day exposure of these rocks indicates an average Quaternary uplift rate of ∼1 mm/yr. The turbidite section on the Burica Peninsula is interpreted to represent a trench-slope deposit and is correlated to a similar, marine sedimentary section on the adjacent Osa Peninsula of Costa Rica. Structures developed within Pliocene-Pleistocene strata of the outer-forearc Burica and Osa Peninsulas record minor (<5%) subhorizontal, margin-perpendicular shortening and margin-perpendicular extension. Bedding orientations on the Osa and Burica Peninsulas generally record arcward tilting by 10°-30° of these outer-forearc blocks. On the Burica Peninsula, the Medial fault zone, a north-striking, high-angle, right-lateral strike-slip (?) fault, has truncated and reoriented the Pliocene-Pleistocene sedimentary sequence by fault-bend (forced) folding. A linear, margin-parallel fault, herein named the "Ballena-Celmira fault zone," bounds the arcward side of the Osa and Burica Peninsulas and has accommodated vertical displacements between the outer forearc (Burica-Osa area) and inner forearc (Terraba area) throughout the Tertiary. Structural and seismicity observations from the forearc region suggest that Neogene deformation of the leading edge of the arc in this area reflects the effects of isostatic uplift, and possibly increased interplate shear stresses, as a result of subduction of the Cocos Ridge beneath this part of the arc since 1 m.y. ago.
Asymmetries in Perception of 3D Orientation

Visual scene interpretation depends on assumptions based on the statistical regularities of the world. People have some preference for seeing ambiguously oriented objects (Necker cubes) as if tilted down or viewed from above. This bias is a near certainty in the first instant (∼1 s) of viewing and declines over the course of many seconds. In addition, we found that there is modulation of perceived orientation that varies with position—for example objects on the left are more likely to be interpreted as viewed from the right. Therefore there is both a viewed-from-above prior and a scene position-dependent modulation of perceived 3-D orientation. These results are consistent with the idea that ambiguously oriented objects are initially assigned an orientation consistent with our experience of an asymmetric world in which objects most probably sit on surfaces below eye level.
Fluorescence Energy Transfer Immunoassay Based on a Long-Lifetime Luminescent Metal–Ligand Complex

We describe an immunoassay based on fluorescence resonance energy transfer (FRET). The antigen was human serum albumin (HSA), which was labeled with a ruthenium-ligand complex, [Ru(bpy)2(phen-ITC)]2+. The antibody (IgG) to HSA was labeled with a nonfluorescent absorber, Reactive Blue 4. Association of the Ru-labeled HSA with the antibody was detected by three spectral parameters, a decreased quantum yield of Ru-HSA, a decrease in its fluorescence lifetime, and an increase in its fluorescence anisotropy. The steady-state anisotropy of Ru-HSA increased approximately eightfold upon binding to the antibody. These spectral effects were observed both in the direct association of the Ru-HSA with Reactive Blue 4-labeled antibody, and in a competitive assay format wherein unlabeled HSA competed with Ru-HSA for the binding sites on the antibody. Some nonspecific interactions of HSA may have occurred with Reactive Blue 4-labeled AHA, a difficulty which can be avoided with a different acceptor. The use of FRET provides a reliable means to alter the spectral properties upon antigen-antibody binding. The advantages of a ruthenium-ligand fluorophore include its long-wavelength absorption and emission, long fluorescence lifetime, and high photo-stability. Long wavelengths minimize problems of autofluorescence from biological samples, and long life-times allow off-gating of the prompt autofluorescence.
Thin skin: the cortical signature of prodromal AD?

Three structural MRI techniques have been developed in recent years to study patients with mild cognitive impairment (MCI) and Alzheimer disease (AD): MRI volumetry,1 voxel-based morphometry (VBM),2 and surface-based morphometry (SBM).3 Since patients with amnestic MCI progress to AD at a rate of approximately 12% per year,4 the aim of many of these studies has been to identify quantitative structural measures (e.g., ventricular volume, whole-brain volume, hippocampal/entorhinal cortical volume, cortical thickness) that accurately predict the progression of amnestic MCI to AD and can therefore serve as surrogate markers of disease progression in therapeutic trials.] In this issue of Neurology ®, Bakkour et al.5 describe the use of structural MRI and FreeSurfer-generated estimates of cortical thickness6 to determine 1) if a quantifiable in vivo cortical signature of AD-related thinning is present in patients with questionable dementia (QAD, defined as Clinical Dementia Rating [CDR] = 0.5), 2) if …
Asian stock markets and the Severe Acute Respiratory Syndrome (SARS) epidemic: implications for health risk management

Time series statistical methods are used to study the financial impact of the Severe Acute Respiratory Syndrome (SARS) epidemic via the co-integration (interdependence) of time series of indexes of several Asian stock markets. We find that during and after the SARS influenza crisis, stock market returns of the infected countries exhibited significant increase in co-integrated relationship and dynamic co-movements, compared to the pre-SARS period. We also find that the effect of the SARS outbreak extended well beyond the Greater China region and influenced most Southeast Asian countries; our empirical results support the notion of 'Globalisation of Commerce and Epidemics'. Furthermore, the findings have several implications for risk managers in the public health sector; we suggest a risk management model for preparing resources against future pandemics of infectious diseases, such as the A-H1N1 influenza.
The effect of microstructure on the interrelationship of electrical, optical and opto-electronic properties in amorphous SixHy alloy films prepared by planar R.F. Magnetron Sputtering

Abstract The electrical dark conductivity ( σ dark ), the photoconductivity ( σ ph ), the photoconductive gain ( σ ph / σ dark ) and the optical gap (E g ) are observed to be strongly correlated in sputtered amorphous Si x H y (a-Si x H y ) films. The form of the interdependence between various parameters is predominantly influenced by the microstructure.
An ecological risk assessment of the exposure and effects of 2,4-D acid to rainbow trout (Onchorhyncus mykiss).

Numerous state and federal agencies are increasingly concerned with the rapid expansion of invasive, noxious weeds across the United States. Herbicides are frequently applied as weed control measures in forest and rangeland ecosystems that frequently overlap with critical habitats of threatened and endangered fish species. However, there is little published chronic toxicity data for herbicides and fish that can be used to assess ecological risk of herbicides in aquatic environments. We conducted 96-h flowthrough acute and 30-day chronic toxicity studies with swim-up larvae and juvenile rainbow trout (Onchorhyncus mykiss) exposed to the free acid form of 2,4-D. Juvenile rainbow trout were acutely sensitive to 2,4-D acid equivalent at 494 mg/L (95% confidence interval [CI] 334–668 mg/L; 96-h ALC50). Accelerated life-testing procedures, used to estimate chronic mortality from acute data, predicted that a 30-day exposure of juvenile rainbow trout to 2,4-D would result in 1% and 10% mortality at 260 and 343 mg/L, respectively. Swim-up larvae were chronically more sensitive than juveniles using growth as the measurement end point. The 30-day lowest observable effect concentration (LOEC) of 2,4-D on growth of swim-up larvae was 108 mg/L, whereas the 30-day no observable effect concentration (NOEC) was 54 mg/L. The 30-day maximum acceptable toxicant concentration (MATC) of 2,4-D for rainbow trout, determined as the geometric mean of the NOEC and the LOEC, was 76 mg/L. The acute:chronic ratio was 6.5 (i.e., 494/76). We observed no chronic effects on growth of juvenile rainbow trout at the highest concentration tested (108 mg/L). Worst-case aquatic exposures to 2,4-D (4 mg/L) occur when the herbicide is directly applied to aquatic ecosystems for aquatic weed control and resulted in a 30-day safety factor of 19 based on the MATC for growth (i.e., 76/4). Highest nontarget aquatic exposures to 2,4-D applied following terrestrial use is calculated at 0.136 mg/L and resulted in a 30-day safety factor of 559 (e.g., 76/0.163). Assessment of the exposure and response data presented herein indicates that use of 2,4-D acid for invasive weed control in aquatic and terrestrial habitats poses no substantial risk to growth or survival of rainbow trout or other salmonids, including the threatened bull trout (Salvelinus confluentus).
Free-stream turbulence and the development of cross-flow disturbances

The cross-flow instability that arises in swept-wing boundary layers has resisted attempts to describe the path from disturbance initiation to transition. Following concerted research efforts, surface roughness and free-stream turbulence have been identified as the leading providers of initial disturbances for cross-flow instability growth. Although a significant body of work examines the role of free-stream turbulence in the cross-flow problem, the data more relevant to the flight environment (turbulence intensities less than 0.07 %) are sparse. A series of recent experiments indicates that variations within this range may affect the initiation or growth of cross-flow instability amplitudes, hindering comparison among results obtained in different disturbance environments. To address this problem, a series of wind tunnel experiments is performed in which the free-stream turbulence intensity is varied between 0.02 % and 0.2 % of free-stream velocity, . Measurements of the stationary and travelling mode amplitudes are made in the boundary layer of a 1.83 m chord, swept-wing model. These results are compared to those of similar experiments at higher turbulence levels to broaden the current knowledge of this portion of the cross-flow problem. It is observed that both free-stream turbulence and surface roughness contribute to the initiation of unsteady disturbances, and that free-stream turbulence affects the development of both stationary and unsteady cross-flow disturbances. For the range tested, enhanced free-stream turbulence advances the transition location except when a subcritically spaced roughness array is employed.
Workshop on Developing Effective Teaming & Presentation Skills to Facilitate Collaborative Software Development

In today's global work environment, inclusive and clear communication has become increasingly important. Educators have the responsibility to equip computer science and software engineering undergraduates with communication skills that can help them, as budding professionals, to manage these global challenges. Participants of this workshop will learn about a spectrum of work approaches and communication styles; they will learn to use this information so that they may teach students how to develop more effective teaming skills and more effective technical presentations related to software development. If students are armed with such skills, they will carry keys to successful collaborative software development.
Surface plasmon resonance enhanced transmission of light through gold-coated diffraction gratings.

Narrow peaks are observed in the transmission spectra of p-polarized light passing through a thin gold film that is coated on the surface of a transparent diffraction grating. The spectral position and intensity of these peaks can be tuned over a wide range of wavelengths by simple rotation of the grating. The wavelengths where these transmission peaks are observed correspond to conditions where surface plasmon resonance occurs at the gold−air interface. Light diffracted by the grating couples with surface plasmons in the metal film to satisfy the resonant condition, resulting in enhanced light transmission through the film. Notably, this phenomenon is not observed at flat, gold-coated surfaces or uncoated gratings, where coupling to surface plasmons does not occur. The nature of the coupling and, thus, the details of light transmission are governed by the momentum matching conditions between the diffracted light and the surface plasmons. In the presence of bound analytes or surface films, the enhanced tr...
U.S.-Mexico trade liberalization and its effects on small-scale enterprises in two distinct regions : West Central Mexico and the Texas border region compared

As has been widely recognized in the literature, the post‐war economic boom which drew to a close by the early 1970s has been followed by an intense period of industrial restructuring characterized by marked instability in all three major spheres of economic activity: production, distribution, and finance. This process has taken place both at the global level and at the level of national economies (Cardenas, 1990). It reflects a profound change in the mode of capitalist accumulation. Prior to the current round of restructuring, accumulation was taken to be principally the inward‐oriented task of each nation's own economy. Now, it seems that successful capital accumulation (i.e. development) depends most upon a nation's competitive integration into the world market for goods and services (Garrido, 1995). The present mode of accumulation implies an opening of national economies to international trade in commodities and capital, both among the advanced industrial nations and between the industrialized and the newly‐industrializing countries. This has generated a heightened degree of competition among countries and among firms, given that the easy movement of capital, goods, and services has allowed for real competition to emerge among dispersed places around the globe based upon their comparative financial and productive advantages.
Research opportunities in crystalline III–V photovoltaics

Although III-V solar cells have been developed to a high level of performance, opportunities for fundamental advances still exist. For example, new structures could lead to substantial gains in conversion efficiency, multi-junction solar cells could achieve efficiencies well above 50%, and new materials could be developed for applications such as thermophotovoltaics. In this paper, the authors describe research opportunities that could provide the scientific base for substantial enhancements in the performance of crystalline III-V photovoltaic cells.
A novel prospective approach to evaluate trauma recidivism: the concept of the past trauma history.

BACKGROUNDThe purpose of this study was to determine the incidence and burden of trauma recidivism at a regional Level 1 trauma center by incorporating the concept of the past trauma history (PTHx) into the general trauma history.METHODSAll trauma patients who met prehospital trauma criteria and act
Modulation of Na+-Ca2+ exchange and Ca2+ permeability in cardiac sarcolemmal vesicles by doxylstearic acids

Abstract We examine the effects of 5-, 12- and 16-doxylstearic acids on the Na + -Ca 2+ exchange and passive Ca 2+ permeability of cardiac sarcolemmal vesicles. Stearic acid is a weak stimulator of Na + -Ca 2+ exchange. A doxyl moiety potentiates stimulation with the order of increasing potency being 5-, 12- and then 16-doxylstearic acid. Stearic acid has little effect on vesicle Ca 2+ permeability but again the doxylstearates are more effective. The sequence of potency is reversed, however, from that for increasing Na + -Ca 2+ exchange. 5-Doxylstearic acid most markedly exchances passive Ca 2+ flux followed by the 12-, and then 16-doxylstearic acids. Methyl esters of the doxylstearates have no effect on either Na + -Ca 2+ exchange or Ca 2+ permeability. We model the results as follows. For a fatty acid to stimulate Na + -Ca 2+ exchange activity, an anionic charge is required to interact with the exchanger protein at the membrane surface. Stimulation is potentiated by a perturbation (such as provided by a doxyl group) within the lipid bilayer. The perturbation is most effective at a location towards the center of the bilayer. To increase passive Ca 2+ permeability an anionic charge is again essential. Disorder within the bilayer is also important, but now the most important site is near the membrane surface. Results of experiments with linolenic and γ-linolenic acid and previous studies with other fatty acids also support this model.
Local cerebral glucose metabolism during controlled hypoxemia in rats

2-Deoxy-[14C]glucose metabolism was examined in brains of hypoxic, normotensive rats by autoradiography, which revealed alternating cortical columns of high and low metabolism. Activity in white matter was increased severalfold over that in adjacent gray matter. The columns were anatomically related to penetrating cortical arteries with areas between arteries demonstrating higher rates of metabolism. The results suggest the presence of interarterial tissue oxygen gradients that influence regional glucose metabolism. The relatively greater sensitivity of white matter metabolism to hypoxia may lead to an understanding of white matter damage in postanoxic leukoencephalopathy.
Outcomes After Bidirectional Cavopulmonary Shunt in Infants Less Than 6 Months Old

Abstract Objectives. We sought to assess the results after bidirectional cavopulmonary shunt (BCPS) in infants Background. Although BCPS is a well established procedure for the palliation of patients with a single-ventricle heart, there have been very few reports of outcomes after BCPS in young infants. Methods. Since 1990, 42 infants between 0.8 and 6.0 months of age (mean [±SD] 3.7 ± 1.4) have undergone BCPS for primary (n = 16) or secondary (n = 26) palliation of tricuspid atresia (n = 13), hypoplastic left heart syndrome (n = 10) or other forms of functional single-ventricle heart (n = 19). Accessory pulmonary blood flow was included in 18 patients. Preoperative and perioperative data were gathered on retrospective review of patient records, and follow-up was conducted by means of direct physician contact or record review. Results. The overall hospital mortality rate, including that associated with reoperations, was 4.8% (2 of 42 patients). Seven patients (17%) required reoperation related to the BCPS or pulmonary blood flow in the early postoperative period: Procedures included take-down of the BCPS in four patients, with one early death, and procedures to decrease pulmonary blood flow in three patients. Age 2 months old. Four patients have undergone successful Fontan completion (18.3 ± 2.9 months postoperatively), and one patient whose BCPS was taken down subsequently underwent successful restoration of a BCPS. Conclusions. Outcomes after BCPS in young infants are comparable to those in older infants and children. However, our current preference is to defer this procedure until after 2 months of age. (J Am Coll Cardiol 1997;29:1365–70)
Accounting methods and managerial discretion: The case of dollar‐value LIFO

This paper focuses on inconsistencies in cost-flow behavior associated with the use of dollarvalue LIFO. These inconsistencies can lead to confusing inventory valuations, potentially misleading accounting reports, incorrect purchasing decisions, and unanticipated tax results. Understanding these effects will enhance the use of dollar-value LIFO as a management tool and will improve the interpretation of financial accounting information. With dollar-value LIFO for multiple items, much of the conventional wisdom about LIFO vanishes. The relationships among inventory purchases, inventory liquidations, and gross margin are derived.
Survey of Doctoral Programs in Personality and Social Psychology, 1992

The size, admissions, support for students, requirements, curriculum content, completion rates, and student placements of 57 doctoral programs in personality and social psychology were surveyed in 1992. Programs offering more financial support were more selective in admissions and had higher completion rates. Larger programs attracted students with higher Graduate Record Examination (GRE) scores but placed a smaller proportion of graduates into psychology departments. Programs with higher GRE scores and more placement success had a higher proportion of minority students. Comparisons with a similar survey conducted 6 years earlier showed that there were fewer programs in 1992 but that they offered their students more financial support and placed a higher proportion of graduates in academic or postdoctoral jobs. Programs in 1992 had more requirements but less curricular coverage of the content surveyed. Possible reasons for these changes, how to measure program quality, program types, and directions for fut...
A Simple One-Pot Method for 6-Oxopurine Ribonucleoside Synthesis: Control and Mechanism of Isomer Distribution

Abstract Combination of bis(trimethylsilyl)acetamide as a silylating reagent and trimethylsilyl trifluoromethanesulfonate as a catalyst forms an exceptionally stable system for a facile one-pot preparation of 6-oxopurine ribonucleosides. The 7β isomer of the ribonucleosides, formed first, is converted into the 9β isomer presumably via the 7,9-diribonucleoside. The procedure affords both 7β and 9β isomers, but finally yields the 9β isomer as the main product.
Non‐ossifying fibroma or benign lipoblastoma of bone–an electron‐microscopic and histochemical study

An ultrastructural and histochemical analysis was made of a lesion identified by light microscopy as a non-ossifying fibroma of bone. A histogenetic sequence was traced from spindle-shaped fibroblast-like cells to multivacuolated lipoblasts with abundant glycogen. These lipid-laden cells showed remarkable similarity to some cells of a well differentiated liposarcoma. Others have interpreted the lipid-containing cells of non-ossifying fibroma as representing fibroblasts which have imbibed or synthesized lipid or lipid-laden macrophages. Our studies demonstrate that this tumour consists of primitive mesenchymal cells with partial maturation to early lipoblasts, suggesting its classification as a benign lipoblastoma of bone.
Radial electron-beam-breakup transit-time oscillator

A radial electron-beam-breakup transit-time oscillator (RBTO) provides a compact high power microwave generator. The RBTO includes a coaxial vacuum transmission line having an outer conductor and an inner conductor. The inner conductor defines an annular cavity with dimensions effective to support an electromagnetic field in a TEM00m mode. A radial field emission cathode is formed on the outer conductor for providing an electron beam directed toward the annular cavity electrode. Microwave energy is then extracted from the annular cavity electrode.
Estimating health expenditure shares from household surveys

OBJECTIVE: To quantify the effects of household expenditure survey characteristics on the estimated share of a household's expenditure devoted to health. METHODS: A search was conducted for all country surveys reporting data on health expenditure and total household expenditure. Data on total expenditure and health expenditure were extracted from the surveys to generate the health expenditure share (i.e. fraction of the household expenditure devoted to health). To do this the authors relied on survey microdata or survey reports to calculate the health expenditure share for the particular instrument involved. Health expenditure share was modelled as a function of the survey's recall period, the number of health expenditure items, the number of total expenditure items, the data collection method and the placement of the health module within the survey. Data exists across space and time, so fixed effects for territory and year were included as well. The model was estimated by means of ordinary least squares regression with clustered standard errors. FINDINGS: A one-unit increase in the number of health expenditure questions was accompanied by a 1% increase in the estimated health expenditure share. A one-unit increase in the number of non-health expenditure questions resulted in a 0.2% decrease in the estimated share. Increasing the recall period by one month was accompanied by a 6% decrease in the health expenditure share. CONCLUSION: The characteristics of a survey instrument examined in the study affect the estimate of the health expenditure share. Those characteristics need to be accounted for when comparing results across surveys within a territory and, ultimately, across territories.
Molecular Weight of Deoxyribonucleic Acid Synthesized During Initiation of Chromosome Replication in Escherichia coli

Alkaline sucrose gradients were used to study the molecular weight of deoxyribonucleic acid (DNA) synthesized during the initiation of chromosome replication in Escherichia coli 15 TAU-bar. The experiments were conducted to determine whether newly synthesized, replication origin DNA is attached to higher-molecular-weight parental DNA. Little of the DNA synthesized after readdition of required amino acids to cells previously deprived of the amino acids was present in DNA with a molecular weight comparable to that of the parental DNA. The newly synthesized, low-molecular-weight DNA rapidly appeared in higher-molecular-weight material, but there was an upper limit to the size of this intermediate-molecular-weight DNA. This limit was not observed when exponentially growing cells converted newly synthesized DNA to higher-molecular-weight material. The size of the intermediate-molecular-weight DNA was related to the age of the replication forks, and the size increased as the replication forks moved further from the replication origin. The results indicate that the newly synthesized replication origin DNA is not attached to parental DNA, but it is rapidly attached to the growing strands that extend from the replication fork to the replication origin, or to the other replication fork if replication is bidirectional. Experiments are reported which demonstrate that the DNA investigated was from the vicinity of the replication origin and was not plasmid DNA or DNA from random positions on the chromosome.
2010 Informal Nutrition Symposium Remodeling the intestinal ecosystem toward better performance and intestinal health

SUMMARY the intestinal microbiota are composed of a large diversity of microorganisms. some have been cultured and characterized, but most remain uncultivated and thus uncharacterized. the intestinal microbiota play a significant role in host health, nutrition, physiology, and performance. In recent studies, researchers have focused on the complex mechanisms involved in host-microbiota symbiosis. Host physiological homeostasis contributes to the stability and composition of the microbiota. Very little is known about microbial competition or metabolism within the intestinal environment, and even less is known about how microbial interactions influence intestinal health and pathogen exclusion. Here we explore factors such as the challenges of studying the intestinal microbiota, how the composition of the microbiota is affected by intestinal substrates and the host corporeal composition, and whether it is possible to explain the effects of the intestinal microbiota modified by growth promoters. Finally, we discuss the desirable effects of growth promoters on the microbiota with regard to intestinal health and pathogen exclusion. Understanding how feed additives affect the intestinal community and the gut environment is the first step in designing strategies to manipulate performance and gut health.
Is the stock market sticker shocked? A study of market response to recent CAFE regulations in the US

In response to increasing environmental concerns, to improve energy security and to conserve energy use, the US government has proposed a new round of Corporate Average Fuel Economy (CAFE) standards. Many studies have focused on how the CAFE standard can be met by various automakers that have sales in the US market, and the costs and benefits of the companies meeting the standard. However, the stock markets’ view on the impact of the standard on automakers’ profitability is largely absent. We study the more recent episode of the CAFE regulation in an effort to try to detect the market response using the standard event study method. Our empirical findings suggest that while the stock market had some responses to the regulation, the large-scale and systematic reaction to the regulation is absent. In addition, the market response pattern to the regulation appears to be tied to the individual company’s compliance condition if there is any significant response at all.
Correlates of kidney stone disease differ by race in a multi-ethnic middle-aged population: The ARIC study

Objective To identify correlates of kidney stone disease in white and African American men and women in a population-based longitudinal study starting in four US communities, and to assess differences in correlates across racial groups.
Root Exudates Regulate Soil Fungal Community Composition and Diversity

Plants are in constant contact with a community of soil biota that contains fungi ranging from pathogenic to symbiotic. A few studies have demonstrated a critical role of chemical communication in establishing highly specialized relationships, but the general role for root exudates in structuring the soil fungal community is poorly described. This study demonstrates that two model plant species (Arabidopsis thaliana and Medicago truncatula) are able to maintain resident soil fungal populations but unable to maintain nonresident soil fungal populations. This is mediated largely through root exudates: the effects of adding in vitro-generated root exudates to the soil fungal community were qualitatively and quantitatively similar to the results observed for plants grown in those same soils. This effect is observed for total fungal biomass, phylotype diversity, and overall community similarity to the starting community. Nonresident plants and root exudates influenced the fungal community by both positively and negatively impacting the relative abundance of individual phylotypes. A net increase in fungal biomass was observed when nonresident root exudates were added to resident plant treatments, suggesting that increases in specific carbon substrates and/or signaling compounds support an increased soil fungal population load. This study establishes root exudates as a mechanism through which a plant is able to regulate soil fungal community composition.
Lung cancer following lung transplant: Single institution 10 year experience

Abstract Background Lung cancer following lung transplantation is an infrequent occurrence of post-transplant neoplasia. Tumors are classified based on donor or recipient origin. Recipient tumors can be diagnosed in explanted specimens or found in contralateral native lungs which remain in place during single lung transplant (SLTx). The aim of our study was to review our institution's incidence of post lung transplant lung cancer, describe tumor histology, and review our experience with their outcomes. Methods A total of 335 lung transplants from 2001 to 2010 were reviewed. Patients were identified with a post-transplant diagnosis of lung cancer, neoplasia, or mass. Fifteen patients were identified; two were excluded due to concomitant cancers with which the lung cancer would represent a metastasis. Retrospective chart review was undertaken for thirteen patients for descriptive statistics, tumor characteristics and overall survival. Results Overall incidence of lung cancer following transplant was 13 cases (3.88%). Six tumors were found in native explanted lungs and six developed subsequently in native lungs. One tumor was confirmed to be of donor origin. Histology included squamous cell in five (38.4%), adenocarcinoma in four (30.7%), and one patient each with adenosquamous (7.6%), carcinoid (7.6%), small cell (7.6%), or malignant solitary fibrous tumor (7.6%). Mean age at transplant was 65 ± 3 years. Mean time from transplant to diagnosis is reported as 241 ± 7 days (range 1–1170). Each patient had at least a 20 pack year smoking history with a mean of 45 ± 3 years. One-year survival for those with lung cancer following transplant was 42.8% while 1 year survival of all lung transplants at our institution is 85.7%. Conclusion Lung cancer incidentally found at the time of transplant or following transplantation is a serious complication with a noted effect on overall survival. The infrequent occurrence of donor tumors represents an adequate screening process of potential young donor lungs. The recognition of cancers in explanted specimens brings to question policies regarding screening of potential recipients with extensive smoking history. A high index of suspicion for native tumors is needed when conducting post-transplant surveillance as these tumors tend to be stage 4 at time diagnosis.
A comparison of nebulizers for microbore LC-ICP-MS with mobile phases containing methanol

A comparison was made between a glass concentric nebulizer, a microconcentric nebulizer (MCN), and a Micro Mist nebulizer for the introduction of mobile phases containing varying concentrations of methanol. For all nebulizers investigated, the signal remains constant with increasing sample flow rate at methanol concentrations greater than 20% of the mobile phase, even though the rate that sample reaches the plasma increases at increasing flow rates. A separation of tributlytin chloride (TBT) and triphenyltin chloride (TPhT) on a microbore reversed-phase HPLC column using a mobile phase consisting of 70% methanol, 29% water, 1% glacial acetic acid and 4 mM ion pair reagent was investigated. At a flow rate of 0.2 ml min−1, the absolute detection limits for the MCN were slightly higher than those obtained with the Micro Mist nebulizer or the glass concentric nebulizer. Precision and the linearity of the calibration curves were comparable for all three nebulizers.
Attention and consciousness : two distinct brain processes

The close relationship between attention and consciousness has led many scholars to conflate these processes. This article summarizes psychophysical evidence, arguing that top-down attention and consciousness are distinct phenomena that need not occur together and that can be manipulated using distinct paradigms. Subjects can become conscious of an isolated object or the gist of a scene despite the near absence of top-down attention; conversely, subjects can attend to perceptually invisible objects. Furthermore, top-down attention and consciousness can have opposing effects. Such dissociations are easier to understand when the different functions of these two processes are considered. Untangling their tight relationship is necessary for the scientific elucidation of consciousness and its material substrate.