cssi/SciSciGPT-SciSciNet huggingface dataset:
Ground water contaminants and their sources—a review of state reports

Pursuant to section 305(B) of the Clean Water Act of 1987, each state submits biennially a water quality report to the U.S. Environmental Protection Agency (EPA). This paper contains a review of 42 such reports in relation to public ground water supplies. Nineteen states provided monitoring data on a total of 51 organic and 21 inorganic chemicals. Frequently detected contaminants included nitrates, trichloroethylene (TCE), volatile organic compounds (VOCs), arsenic, and fluorides. The most frequently identified contaminant sources were underground storage tanks (35 states), septic tank systems (31), surface impoundments (29), municipal landfills (27), agricultural activities (26), abandoned hazardous waste sites (24), regulated hazardous waste sites (19), land application/treatment (18), injection wells (18), and on‐site industrial and other landfills (16). A total of 146 organic and 30 inorganic chemicals were identified as potential contaminants by 35 states. This composite analysis indicates widespread...
Exact real-space renormalization method and applications

We present a numerical method based on real-space renormalization that outputs the exact ground space of ``frustration-free'' Hamiltonians. The complexity of our method is polynomial in the degeneracy of the ground spaces of the Hamiltonians involved in the renormalization steps. We apply the method to obtain the full ground spaces of two spin systems. The first system is a spin-1/2 Heisenberg model with four-spin cyclic-exchange interactions defined on a square lattice. In this case, we study finite lattices of up to 160 spins and find a triplet ground state that differs from the singlet ground states obtained by Batista and Trugman, [Phys. Rev. Lett. 93, 217202 (2004)]. We characterize such a triplet state as consisting of a triplon that propagates in a background of fluctuating singlet dimers. The second system is a family of spin-1/2 Heisenberg chains with uniaxial exchange anisotropy and next-nearest-neighbor interactions. In this case, the method finds a ground-space degeneracy that scales quadratically with the system size and outputs the full ground space efficiently. Our method can substantially outperform methods based on exact diagonalization and is more efficient than other renormalization methods when the ground-space degeneracy is large.
Limiting factors and population regulation

P 0 I I Opinion is intended to facilitate communication between reader and author and reader and reader. Comments, viewpoints or suggestions arising from published papers are welcome. N Discussion and debate about important issues in ecology, e.g. theory or terminology, may I I also be included. Contributions should be as precise as possible and references should be P 0 kept to a minimum. A summary is not required. o N
The Perils of the Back Seat: Date Rape, Race and Gender in 1950s America

Dating among white American teenagers in the 1950s caused parents considerable concern, as it represented disturbing developments in sexual expectations. While the rhetoric surrounding marriage celebrated traditional gender roles and monogamy, Americans bemoaned social and moral decay, caused in part by women's encroachment on male prerogatives. Sexual experience for boys increasingly became a defining gender characteristic and a means of achieving manhood as well. Ideas about proper marital norms and studies of dating practices among young people naturalised male aggression as proof of masculinity, which made girls, even ‘respectable ones’, vulnerable to violence from their dates. As teens' acceptance of going steady became more widespread, older racialised narratives of sexual danger evolved to incorporate new dating trends. Whereas American, and especially southern white, women knew the dangers of the supposed ‘black beast rapist’, they learnt during the 1950s that a special danger could confront them in the back seat of cars, despite the presence of their white, male date. Even with a white protector, white women remained vulnerable to violence on dates, whether from black men or from their white date. As dating conventions loosened, white women found that that the perils of the back seat only increased.
Neurofibromatosis 1 mRNA Expression in Blood Vessels

Vascular hypertrophic lesions occur in neurofibromatosis type 1 (NF1). The role of the gene which causes NF1 in the growth and development of blood vessels is not known. mRNA expression of the NF1 gene was studied in blood vessels in the transition between intact and culture and in quiescent and proliferative conditions. The expression and alternative splicing pattern of the catalytic domain of NF1 consistently changed in proliferating cells, supporting a role for this gene in the regulation of growth of vascular smooth muscle and the vascular pathology in NF1.
Synergetic thermal effects for oxygen sorption and order–disorder transition on perovskite-type oxides

Abstract Simultaneous DSC-TGA measurements were conducted on a perovskite-type oxide, La 0.1 Sr 0.9 Co 0.9 Fe 0.1 O 3− δ , when it was subject to a sudden change of oxygen activity in the gas environment (from 1.3×10 −4 to 0.21 atm) at constant temperature. The DSC-TGA and XRD results show occurrence of synergetic thermal effects for exothermic oxygen sorption and endothermic oxygen vacancy order to disorder transition for the perovskite-type oxide in response to the sudden increase of oxygen activity in a large temperature range (350–800 °C). The perovskite-type ceramic transforms from the ordered (brownmillerite) to disordered (perovskite type) structure as temperature increases. The order to disorder phase transition temperature decreases with decreasing oxygen nonstoichiometry or increasing oxygen partial pressure, with the maximum transition temperature at 857.9 °C. The apparent heat measured for the perovskite-type ceramic sample during the oxygen sorption process changes from endothermic to exothermic one as temperature increases from 350 to 800 °C. The endothermic heat for phase transformation and exothermic heat for oxygen sorption for the perovskite-type oxide were estimated at 59.8 J/g and −180.5 kJ/mol, respectively, from the DSC-TGA measurements.
Dynamic leadership for human-robot teams

This paper evaluates collaborative tasking tools that facilitate dynamic sharing of responsibilities between robot and operator throughout a search and detection task Participants who utilize Collaborative Tasking Mode (CTM) do not experience a significant performance penalty, yet benefit from reduced workload and fewer instances of confusion. In addition, CTM participants report a higher overall feeling of control as compared to those using Standard Shared Mode.
Robust Estimation of Road Frictional Coefficient

Knowledge of tire force potential, i.e., tire-road frictional coefficient, is important for vehicle active safety systems because tire-road friction is an effective measure of the safety margin of vehicle dynamics. For vehicle handling dynamics, the frictional coefficient is highly coupled with tire slip angle, therefore, they need to be estimated simultaneously when the latter is not measured. This paper presents an estimation algorithm based on a robust adaptive observer methodology. Stability and robustness of this observer are analyzed numerically. The performance is analyzed using computer simulations and experiments under various road and steering conditions.
Endovascular treatment of posterior circulation aneurysms

Endovascular techniques are well suited for the treatment of posterior circulation aneurysms. This review describes the endovascular management of these aneurysms and discusses relevant technical advances.
Some observations on the use of sodium propionate for the prevention of ketosis in dairy cattle.

Summary The herd of Guernsey cattle owned by the University of Delaware, which had previously shown a very high incidence of ketosis, was divided into control and treatment groups which were as near alike as possible in history of ketosis. Cows which calved a second time during the course of the experiment were placed in the group opposite their original group. In this way, 11 of the cows were included in both groups. The treatment group received one-eighth of a pound of sodium propionate twice daily by drench for approximately 6 wk. postpartum. The effect of propionate upon incidence of ketosis, blood sugar levels, blood ketone levels, and milk production was investigated. The incidence of ketosis was low in both groups, but it was just as high in the treated as in the control. There was some tendency for the treated group to be lower in blood ketones and higher in blood glucose than the control group; however, individual variation was too great for these differences to be significant. There was a highly significant difference in milk production favoring the treatment with sodium propionate.
Distribution after repeated oral administration of different dose levels of risperidone and 9-hydroxy-risperidone in the brain and other tissues of rat.

Rats were treated with daily oral doses of 1, 4, and 6 mg/kg risperidone (RSP) and its metabolite, 9-hydroxy-risperidone (9-OH-RSP), for 15 consecutive days. Concentrations of RSP and 9-OH-RSP were measured in plasma, brain, liver, kidney, lungs and fat tissue by high-performance liquid chromatography with electrochemical detection. Non-specific distribution of RSP and 9-OH-RSP in various brain regions was also studied after administration of 6 mg/kg per day oral dose for 15 days. After RSP treatment, concentrations of 9-OH-RSP were higher than those of RSP in plasma and tissues except in brain, where both compounds were present in nearly equal concentrations. Similarly, after 9-OH-RSP treatment, levels of 9-OH-RSP were higher than levels of either RSP or 9-OH-RSP or the sum of RSP and 9-OH-RSP levels measured after treatment with RSP. There was a moderate relationship between RSP dose and tissue levels of RSP and 9-OH-RSP (all r s ≥ 0.62, P < 0.01), except in fat. There was also a strong relationship between the dose and tissue levels of 9-OH-RSP (all r s≥ 0.68, P < 0.005). A significant relationship was found between plasma levels of RSP and brain levels of RSP and 9-OH-RSP (all r s ≥ 0.57, P < 0.03) after treatment with RSP. After 9-OH-RSP treatment, a much stronger relationship was observed between plasma and brain 9-OH-RSP levels (r s ≥ 0.90, P < 0.005). The plasma concentrations of RSP and 9-OH-RSP appear to reflect their concentrations in brain. The tissue-to-plasma ratios of RSP and 9-OH-RSP were relatively low compared to other antipsychotics. In liver, kidney and lung the tissue to plasma ratio for RSP and 9-OH-RSP after treating with RSP ranged from 0.85 to 3.4. The brain to plasma ratio for RSP and 9-OH-RSP was several-fold lower than that in peripheral tissues. After RSP administration, the mean brain to plasma level ratio for RSP was 0.22, and for 9-OH-RSP to it was 0.04. The brain to plasma ratio of 9-OH-RSP after giving 9-OH-RSP was similarly low (0.04). The low brain/plasma ratio of high potency RSP and 9-OH-RSP may in part be due to their low lipophilicity, log P = 3.04 and 2.32, respectively, resulting in limited non-specific accumulation in brain tissue.
Domains for G-protein coupling in angiotensin II receptor type I: studies by site-directed mutagenesis.

To delineate domains essential for G-protein coupling in angiotensin II type 1 receptor (AT1), we mutated the receptor cDNA in the putative cytosolic regions and determined consequent changes in the effect of GTP analogs on angiotensin II (Ang II) binding and in inositol trisphosphate production in response to Ang II. Polar residues in targeted areas were replaced by small neutral residues. Mutations in the second cytosolic loop, carbocy terminal region of the third cytosolic loop or deletional mutation in the carboxyl terminal tail simultaneously abolished both the GTP-induced shift to the low affinity form and Ang II-induced stimulation of inositol trisphosphate production. These results suggest that polar residues in the second cytosolic loop, the carboxy terminal region of the third cytosolic loop, and the carboxy terminal cytosolic tail are important for G-protein coupling of AT1 receptor.
Consistency questions in the light cone gauge based on equal time commutation rules

Abstract We investigate whether time displacement invariant propagators are compatible canonical formulations in the light cone gauge based on equal time commutation rules. We conclude that, in the light cone gauge, time displacement invariant propagators are not consistent with the requirement that, in canonical formulations of gauge theories, only transversely polarized, massless gauge field excitations (photons, or gluons in perturbative QCD), can contribute to the transverse part of a time displacement invariant propagator. When the time displacement invariant light cone gauge propagator is represented as a four-dimensional momentum space Fourier integral the following is observed: Transverse parts of the propagator obtain time displacement invariant contributions from the ( k 3 − k 0 ) pole, as well as from the ( | k | 2 −k 0 2 ) pole. But since, in the Schrodinger picture (i.e. at t =0), the divergence-free part of the gauge field consists of transversely polarized gauge field excitations only, the transverse part of the propagator either can have time displacement invariant time dependence determined by the ( | k | 2 −k 0 2 ) pole; or, if any part of the transverse propagator has time dependence determined by the ( k 3 − k 0 ) pole, it cannot be time displacement invariant.
The Impact of Nonsteroidal Anti-inflammatory Drugs on Hypertension: Alternative Analgesics for Patients at Risk

An estimated 25% of the overall population of the United States and 55% to 60% of the population aged 65 to 74 years are hypertensive. Many patients with hypertension, particularly elderly patients, also take nonsteroidal anti-inflammatory drugs (NSAIDs), the most commonly prescribed analgesic medications in the United States. It is estimated that as many as 20 million patients and 12% of the population aged > or = 60 years are taking concurrent NSAIDs and antihypertensive medication. This overlap is significant, because NSAIDs inhibit eicosanoid synthesis and can thus limit the effectiveness of antihypertensive drugs that exert all or part of their blood-pressure-lowering action through the stimulation of eicosanoid synthesis or release. Overviews of clinical trial data indicate that the blood pressure of patients with controlled hypertension can be raised by 3 to 6 mm Hg during concurrent treatment with NSAIDs, which can produce a significant increase in subsequent stroke, end-stage renal disease, or congestive heart failure. The incidence of these sequelae increases with age. Clinicians should have greater awareness of the potential impact of NSAIDs on blood pressure control, especially in high-risk patients such as the elderly and those with chronic pain or uncontrolled hypertension. Unless an NSAID is deemed absolutely necessary, the clinician should consider alternative analgesics that do not affect prostaglandin synthesis. These include acetaminophen, tramadol, and, in some cases, narcotic analgesics.
High-Intensity Transmission Properties Of Conventional And Polymeric Index-Matching Fluids

Large-aperture harmonic generation is rapidly becoming a standard practice in laser-fusion research. At present, harmonic generation is commonly done with bare nonlinear crystals--that is, crystal plates not protected from atmospheric degradation, and not relieved of Fresnel loss, by anti-reflection windows and index-matching fluid. This situation has been dictated by the recently-observed, aperture-dependent nonlinear loss in harmonic generation cells using layers of conventional index-matching fluids (Cargille 5610 and FC104). While the overall cost of using bare crystals can be tolerated at the small apertures (10-15 cm) in use at present, for the 74-cm harmonic crystal arrays to be used on the Nova laser, loss-free and degradation-free performance is required. In this paper, results will be presented from a study of the 0.53-pm and 1.06-pm high-intensity transmission properties of 10 organic fluids: benzonitrile, benzene, xylene, tetrachloroethylene, acetonitrile, decahydronaphtalene, Cargille 5610, FC104, poly-chlorotrifluoroethylene (Halocarbon 56) and poly-bromotrifluoroethylene (BFC57). We present measurements of the threshold for stimulated Raman scattering (SRS) in 8 of the fluids in a standardized 8-cm, longitudinal geometry. In the two polymeric fluids, SRS was not detected at input intensities up to the superbroadening thresholds (43 and 62 GW/cm2, respectively). Suppression of SRS in these two fluids is achieved by fluorination and polymerization of the parent tetrachloroethylene molecule. Results will also be related from tests in the required transverse geometry, using 8-cm aperture, 0.532-pm pulses of up to 3 GW/cm2. The aforementioned loss mechanism in Cargille 5610 is identified to be transverse stimulated Raman scattering. Finally, we describe a successful demonstration of loss-free, damage-free performance at an aperture-intensity product of 25 GW/cm in Halocarbon 56 fluid.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Artificial Reefs: The Importance of Comparisons with Natural Reefs

Abstract Methods used to evaluate the performance of an artificial reef will vary according to the purpose for which the reef was built. To determine how well artificial reefs mitigate losses due to human activities on natural reefs, the performance of artificial reefs should be evaluated using contemporaneous comparisons with relatively undisturbed natural reefs. Unfortunately, comparisons between artificial and natural reefs are typically confounded by differences in reef size, age, and isolation. We compared colonization and subsequent assemblage structure of reef fishes on coral and artificial (concrete block) reefs in which reef size, age, and isolation were standardized. Species richness and fish abundance (all species combined) were greater on reefs of natural rather than artificial structure, but substantial differences in species composition were not detected. Our results suggest that artificial reefs with structural complexity and other abiotic and biotic features similar to those of natural ree...
Thermal decomposition of some perfluoroalkyl grignard reagents. Synthesis of trans-1-halo and trans-1-alkylperfluorovinyl compounds

Abstract The thermal decomposition of perfluoroalkyl Grignard reagents (R f MgX), formed from halogen-metal exchange with alkyl Grignard reagents, provides a good synthetic route to trans -1-haloperfluorovinyl compounds. The decomposition of R f MgX (where X = Cl, Br, I) in the presence of RMgX generally leads to a mixture of trans -1-alkylperfluorovinyl and trans -1-haloperfluorovinyl compounds. However, the choice of RMgX with respect to both the alkyl group and halogen is critical as regards the formation of the trans -1-alkylperfluorovinyl compounds. Several possible mechanisms are suggested to account for the experimental observations.
Atomic force microscopy for high-resolution imaging in cell biology

Historically, microscopy has been a tool of primary importance to the cell biologist. The scanning tunnelling microscope I started a revolution in microscopy that has led to the emergence of a family of scanning probe microscopes. These instru- ments pass a probe in close proximity to a surface, and collect spatially re- solved information about surface properties, such as tunnelling current, physical topography, ion conduc- tance or temperature 2. One of the most promising members of this family of instruments for biological applications is the atomic force microscope (AFM, also known as the scanning force microscope)3, 4. On hard samples the AFM can often resolve atoms, while on soft biological materials the lateral resol- ution is currently 1-50 nm. Its ability to image in fluids, including physio- logical buffers, and to gather dy- namic data points to a bright future
THE EFFECTS OF PERSONALITY SIMILARITY ON PEER RATINGS OF CONTEXTUAL WORK BEHAVIORS

The present field study investigates whether rater-ratee similarity in the Big Five personality factors influences peer ratings of contextual work behaviors. It overcomes problems that previous studies have had by using a polynomial regression analysis and by correcting the potential biases from nonindependence. Using more than 500 peer dyads, we found that rater-ratee similarity in Conscientiousness, but not in other dimensions, was positively associated with peer ratings even after controlling for interpersonal affect. These results suggest that the observed effect of personality similarity may reflect actual behavioral differences rather than biases due to interpersonal affect. Implications of the findings are discussed along with recommendations for future research.
Integrating Assessment and Instruction: Easing the Process with PDAs

(2006). Integrating Assessment and Instruction. Journal of Physical Education, Recreation & Dance: Vol. 77, No. 1, pp. 27-52.
On the hydrographic distribution in the source region of the Delaware coastal current

The buoyant discharge from Delaware Bay forms two separate branches of residual outflow near the bay mouth, one along each shore. Upon exiting the bay, the branch along the Delaware shore turns right to form the southward flowing Delaware coastal current along the inner continental shelf off the Delaware, Maryland, and Virginia coasts. CTD and thermosalinograph, data collected at the mouth of Delaware Bay over two semidiurnal tidal cycles are used to examine the hydrographic distribution at the source region of the Delaware coastal current. In this region the buoyant source water of the coastal current, is largely detached from the shoreline and confined to the top 15 m of the water column over much of the tidal cycles. The core of the coastal current's source water, as defined by the point of salinity minimum, is located over the deep channel well offshore of the Delaware coast. The separation between this buoyant water and the more saline waters right along the Delaware coast and that in the central part of the bay mouth are marked by regions of high horizontal salinity gradients. The horizontal salinity gradients around the inshore and offshore boundaries of the source water of the coastal current are intensified during the flood tide, and clearly defined fronts (with a change of 3‰ over a distance of 150 m) are present at the offshore boundary near the end of the flood tide. The structure of the mean flow and the distribution of the brackish coastal current on the inner continental shelf contribute to the persistence of stratification in the source region off the Delaware shore throughout the ebb and flood tides. In contrast, the ebb-induced stratification in the region off the New Jersey shore is quickly destroyed with the onset of the flood current.
Modulators of normal electrocardiographic intervals identified in a large electronic medical record

Background Traditional electrocardiographic (ECG) reference ranges were derived from studies in communities or clinical trial populations. The distribution of ECG parameters in a large population presenting to a healthcare system has not been studied. Objective The purpose of this study was to define the contribution of age, race, gender, height, body mass index, and type 2 diabetes mellitus to normal ECG parameters in a population presenting to a healthcare system. Methods Study subjects were obtained from the Vanderbilt Synthetic Derivative, a de-identified image of the electronic medical record (EMR), containing more than 20 years of records on 1.7 million subjects. We identified 63,177 unique subjects with an ECG that was read as "normal" by the reviewing cardiologist. Using combinations of natural language processing and laboratory and billing code queries, we identified a subset of 32,949 subjects without cardiovascular disease, interfering medications, or abnormal electrolytes. The ethnic makeup was 77% Caucasian, 13% African American, 1% Hispanic, 1% Asian, and 8% unknown. Results The range that included 95% of normal PR intervals was 125–196 ms, QRS 69–103 ms, QT interval corrected with Bazett formula 365–458 ms, and heart rate 54–96 bpm. Linear regression modeling of patient characteristic effects reproduced known age and gender effects and identified novel associations with race, body mass index, and type 2 diabetes mellitus. A web-based application for patient-specific normal ranges is available online at http://biostat.mc.vanderbilt.edu/ECGPredictionInterval. Conclusion Analysis of a large set of EMR-derived normal ECGs reproduced known associations, found new relationships, and established patient-specific normal ranges. Such knowledge informs clinical and genetic research and may improve understanding of normal cardiac physiology.
THE MASSIVE YOUNG STAR-FORMING COMPLEX STUDY IN INFRARED AND X-RAY: MID-INFRARED OBSERVATIONS AND CATALOGS

Spitzer IRAC observations and stellar photometric catalogs are presented for the Massive Young Star-Forming Complex Study in the Infrared and X-ray (MYStIX). MYStIX is a multiwavelength census of young stellar members of 20 nearby (d < 4?kpc), Galactic, star-forming regions that contain at least one O star. All regions have data available from the Spitzer Space Telescope consisting of GLIMPSE or other published catalogs for 11?regions and results of our own photometric analysis of archival data for the remaining 9 regions. This paper seeks to construct deep and reliable catalogs of sources from the Spitzer images. Mid-infrared study of these regions faces challenges of crowding and high nebulosity. Our new catalogs typically contain fainter sources than existing Spitzer studies, which improves the match rate to Chandra X-ray sources that are likely to be young stars, but increases the possibility of spurious point-source detections, especially peaks in the nebulosity. IRAC color-color diagrams help distinguish spurious detections of nebular polycyclic aromatic hydrocarbon emission from the infrared excess associated with dusty disks around young stars. The distributions of sources on the mid-infrared color-magnitude and color-color diagrams reflect differences between MYStIX regions, including astrophysical effects such as stellar ages and disk evolution.
The morphology of the aortic arches in four genera of plethodontid salamanders

The larval, metamorphosing and definitive aortic arches of Desmognathus fuscus, Plethodon cinereus, Eurycea bislineata, and Gyrinophilus porphyriticus, described in this paper, were investigated because it was thought possible that, if the fourth or pulmonary arch failed to develop in these lungless forms, a new factor associated with the loss of lungs might be revealed. The salient points of structure disclosed, so far as the problem involved is concerned, are: D. fuscus and P. cinereus develop fourth arches which remain functional in the larvae and adults and supply the pharynx, oesophagus, stomach and skin of the shoulder region. In some instances the fourth arch in the larvae of P. cinereus is reduced in length or entirely lacking in which cases correspondingly less of the fourth arch and more of the third arch is present in the adult. E. bislineata and undoubtedly G. porphyriticus fail to develop fourth arches and hence do not possess these in either the larval or adult states. It is concluded, therefore, that the failure of the fourth arch to develop has evidently not been a factor involved in the advent of lunglessness in plethodontid salamanders. Also, the fact that E. bislineata never develops a fourth arch, yet is able to transform, furnishes additional evidence against Figge's view that Necturus fails to metamorphose because the ventral portion of the fourth arch is absent.
Nonlinear diffusion in biological systems

Diffusion problem with variable diffusion coefficient in a spherical biological system is investigated. Also included in this study is the biological reaction of the Michaelis-Menten type. The problem formulated consists of a highly nonlinear differential equation which, however, can be efficiently solved by the orthogonal collocation method on a digital computer. The effects of the dimensionless governing parameters on the transient and steady state concentration responses are parametrically examined for the diffusion system with and without biological reaction.
La Crosse virus infectivity, pathogenesis, and immunogenicity in mice and monkeys.

La Crosse virus (LACV), family Bunyaviridae, was first identified as a human pathogen in 1960 after its isolation from a 4 year-old girl with fatal encephalitis in La Crosse, Wisconsin. LACV is a major cause of pediatric encephalitis in North America and infects up to 300,000 persons each year of which 70–130 result in severe disease of the central nervous system (CNS). As an initial step in the establishment of useful animal models to support vaccine development, we examined LACV infectivity, pathogenesis, and immunogenicity in both weanling mice and rhesus monkeys. Following intraperitoneal inoculation of mice, LACV replicated in various organs before reaching the CNS where it replicates to high titer causing death from neurological disease. The peripheral site where LACV replicates to highest titer is the nasal turbinates, and, presumably, LACV can enter the CNS via the olfactory neurons from nasal olfactory epithelium. The mouse infectious dose50 and lethal dose50 was similar for LACV administered either intranasally or intraperitoneally. LACV was highly infectious for rhesus monkeys and infected 100% of the animals at 10 PFU. However, the infection was asymptomatic, and the monkeys developed a strong neutralizing antibody response. In mice, LACV likely gains access to the CNS via the blood stream or via olfactory neurons. The ability to efficiently infect mice intranasally raises the possibility that LACV might use this route to infect its natural hosts. Rhesus monkeys are susceptible to LACV infection and develop strong neutralizing antibody responses after inoculation with as little as 10 PFU. Mice and rhesus monkeys are useful animal models for LACV vaccine immunologic testing although the rhesus monkey model is not optimal.
Tissue ablation with the free-electron laser: contributions of wavelength and pulse structure

The Vanderbilt free-electron laser provides a continuously tunable ((lambda) equals 2 - 10 micrometer) source of pulsed IR radiation with a pulse structure unlike those of conventional lasers (a macropulse of 4.5 ms consisting of a micropulse train of 1 ps pulses separated by 350 ps). Tuned to the vibrational mode of the amide-II band ((lambda) equals 6.45 micrometer), the laser is well suited for precise tissue ablation with reported minimal thermal and collateral tissue damage. However, the relative influences of the pulse structure and wavelength on tissue ablation is still not clear. The effects of different wavelengths ((lambda) equals 2.94, 3.36, and 6.45 micrometer) on tissue ablation were compared using pump-probe imaging of tissue phantoms while simultaneously laser-induced pressures were measured with a piezoelectric needle hydrophone. Bovine heart tissue was ablated in vitro using clinically relevant parameters and laser induced damage was examined histologically. The results of these experiments, and their implications will be discussed.
Dynamic aspects of regulation of ventilation in man during acclimatization to high altitude.

Abstract In order to elucidate the mechanism of ventilatory acclimatization to high altitude, the time course of the change in several ventilatory parameters was measured in 3 adult sea level natives before and serially for 11 days after ascent to 4540 m. The e -P a CO2 response curves at P a O2 = 50 and 200 mm Hg were determined at sea level and during altitude acclimatization. Ventilation and alveolar gas pressures at rest and during three grades of steady state physical exercise were also determined under each of the following conditions of inspired PO2: at sea level — (1) ambient air (150 mm Hg) and (2) acute hypoxia (83 mm Hg) and at 4540 m — (3) ambient air (83 mm Hg) and (4) acute normoxia (150 mm Hg). The P a O2 decreased to about 50 mm Hg at 4540 m from the sea level value of about 105 mm Hg. Resting ventilation increased and P a CO2 decreased to about 70% of sea level values within 3 to 7 days of ascent The ventilatory sensitivity to hypercapnia increased by 80% in 3 days, and the P a CO2 “threshold” decreased by about 70% almost as promptly. The hypoxic sensitivity remained the same throughout the entire period of 11 days. Thus the persistent hyperventilation during acclimatization to high altitude apparently resulted from a maintained hypoxic drive and a heightened CO2 sensitivity, although there may have developed some other ventilatory drive associated with chronic hypoxia.
Failure of prosencephalic unfolding and neuronal migration in acardia

Acardia is a fatal complication of twin pregnancy. It is caused by a retrograde flow of arterial blood from a "pump" into an acardiac twin through placental arterial and venous connections. The heart function of the recipient twin is either blocked or insufficient to support perfusion of the upper body. Severe developmental anomalies ensue. While most acardiacs are anencepahalic, a few twins with a rudimental heart ("hemicardiac") are able to support a variably complex brain. Here we report three cases of hemicardiac twinning with neuronal migrational defects. The most severe abnormalities affected the supratentorial compartment. They can be conceptually divided in two groups. The first, which we tentatively linked to agenesis of the choroid plexus, can be described as a failure of prosencephalic unfolding. The resulting defects included collapsed neocortex, agenesis of the hippocampi and scrambled basal ganglia and diencephalon. The second group of lesions can be theoretically deduced to a result of disruption of the glia-pial boundary with subsequent formation of leptomeningeal heterotopia and zona cerebrovasculosa. Our observations highlight that even in the milieu of a normal genetic background, severe restriction of brain perfusion could lead to neuronal migration defects. Our data also show that adequate unraveling of the brain architecture is crucially dependent on both the parenchymal vascularization and production of the cerebrospinal fluid by the choroid plexus.
Focusing on Native Americans: basic Web resources pathfinder

Provides an introduction to basic Web‐based resources relevant for locating information and identifying other resources that are useful in addressing frequently asked questions about topics and issues centered on Native Americans.
Circulating heavy chain IgG, a pathological mediator for coronary artery disease, recognizes platelet surface receptors of both prostacyclin and insulin.

Although an increased incidence of premature cardiovascular disease has been determined to be the major cause of mortality in subjects with chronic spinal cord injury the identity of the pathophysiological mediators of cardiovascular disease in spinal cord injury remains obscure. Because both insulin and prostacyclin could be important in the prevention of thrombosis, the status of insulin-induced nitric oxide production and the prostacyclin high-affinity receptor interaction in platelets in subjects with spinal cord injury was studied. It was established that the insulin-induced nitric oxide synthesis in platelets from spinal cord-injured subjects was markedly impaired (0.053-0.058, P=0.37-0.44) compared to (0.062-0.53 μM/108 platelets, P<0.001) due to the presence of a free heavy chain IgG (Mr 47 kDa) in the circulation of subjects with spinal cord injury. This IgG not only blocked insulin receptor binding sites (without affecting dissociation constant of the hormone binding, Kd1= 2 × 10−9 M) for the...
Lipid extraction of tissues with a low-toxicity solvent

Abstract An improved method for extracting the lipids from tissues consists of the use of hexane:isopropanol, followed by a wash of the extract with aqueous sodium sulfate to remove nonlipid contaminants. This method has a number of advantages over the common usage of chloroform:methanol. The solvents are somewhat less toxic, interference in processing by proteolipid protein contamination is avoided, the two phase separate rapidly during the washing step, the solvent density is low enough to permit centrifugation of the homogenate as an alternative to filtration, the solvents are cheaper, and the washed extract can be applied to a chromatographic column with continuous monitoring of the elution in the far ultraviolet region. The new extraction method is inefficient for the extraction of gangliosides.
Iwasawa invariants of Λ-adic representation

It is a classical result that the number of primes l for which τ(l) vanishes has Dirichlet density 0, where τ(l) is the Ramanujan τ function. We study an analogous question that arises in studying the Λ-adic representation whose image is full. In particular, we show that the set of primes l for which the trace of the Frobenius at l has positive μ-invariant has Dirichlet density 0. We also discuss the analogous Dirichlet densities related to λ-invariants.
Morphological transitions in the rapid solidification regime: A re-examination of the fundamental validity of the absolute stability concept of Mullins and Sekerka

The validity of the notion of absolute stability (AS) of a planar solid-liquid interface, proposed by Mullins and Sekerka (M-S, 1964), was tested using experimental data obtained for a number of dilute Ag-Cu and Sn-In alloys and for ultrahigh-purity succinonitrile. It is shown that the restriction applied by the M-S theory is satisfied during the steady-state planar solidification in an undercooled melt, provided the undercooling is quite small. The findings obtained on the Ag-Cu and Sn-In alloys are compared with early measurements by Davis and Fryzuk (1971) in dilute Sn-In alloys with 25 to 400 ppm additions of In.
Incision of damaged versus nondamaged DNA by the Escherichia coli UvrABC proteins

Incision of damaged DNA by the Escherichia coli UvrABC endonuclease requires the UvrA, UvrB, and UvrC proteins as well as ATP hydrolysis. This incision reaction can be divided into three steps: site recognition, preincision complex formation, and incision. UvrAB is able to execute the first two steps in the reaction while the addition of UvrC is required for the incision of DNA. This incision reaction does not require ATP hydrolysis and results in the formation of a tight UvrABC post-incision complex and the generation of an oligomer of approximately 12 nucleotides. At high UvrABC concentrations the specificity of the incision for damaged DNA is decreased and significant incision of undamaged DNA occurs. Analogous to damage specific incision, this type of incision leads to generation of an oligonucleotide, but in this case the size is approximately 9 nucleotides in length. Further evidence shows that the combination of UvrB and UvrC proteins can generate a significant amount of a similar size product on undamaged DNA. In addition, the UvrC protein alone can generate a small amount of the same product. Immunological characterization of the weak nuclease activity seen with UvrC indicates that the activity is very tightly associated with the purified UvrCmore » protein.« less
A Modest Proposal in Response to Rhodes and Schiano

In addressing the ethics of transplant tourism, Rosamond Rhodes and Thomas Schiano (2010) commend a general conception of medical ethics and advance a set of specific policy proposals. They propose...
Turnip crinkle virus infection from RNA synthesized in vitro.

Abstract Genome-length cDNA clones of turnip crinkle virus (TCV) were constructed with Sma l and Xba l restriction sites engineered at the 5′ and 3′ termini, respectively. The genome-length cDNAs were positioned downstream of modified λ and T7 phage promoters such that in vitro transcription resulted in RNAs with 5 extra nucleotides at the 3′ end, and 1, 2, or 14 extra nucleotides at the 5′ end depending on the construction. Transcripts with 14 extraviral 5′ nucleotides were not infectious, while transcripts with 1 or 2 additional 5' nucleotides, with or without 5′-cap analog included in transcription reactions, were biologically active. These were approximately an order of magnitude less infectious than RNA extracted from TCV virions. The additional 5′ nucleotides were not maintained in progeny viral RNAs isolated from plants.
Volatile products of oxidative pyrolysis of wood: Influence of metal ions

Abstract The volatile products from pyrolysis of wood in air have been determined by coupled thermal gravimetry/Fourier transform infrared spectrometry (TG/FTIR), both isothermally at 523 K and with progressive heating to 750 K. The results are compared with a similar early study of pyrolysis in nitrogen. The presence of oxygen increases the rate and extent of formation of water and of carbon dioxide at 523 K and induces the formation of carbon monoxide. Removal of indigenous metal ions and replacement by potassium or by calcium ions showed that catalysis by potassium of both pyrolysis and oxidation is dominant in wood for most types of reaction channel. At higher temperatures the influence of the potassium ions is very marked in catalysis of char oxidation by air, resulting in ignition and sudden formation of carbon monoxide, carbon dioxide, and water.
Quasiperiodic tilings generated by matrices

Abstract Using the inflation method, Watanabe, Ito and Soma [3], Clark and Suryanarayan [4] and Balagurusamy, Ramesh and Gopal [5] have obtained nonperiodic tilings of the plane with n-fold rotational symmetry, n = 2, 3, 4, 5, 8, using two unit prototiles. Fortunately, there is an easier way to generate a more general class of nonperiodic tilings which contains the above-mentioned tilings as special cases. We do this by specifying two matrices of order two which define the two classes of tilings; thus, our approach uses the basic techniques from linear algebra in the study of quasiperiodic tilings and the method can be generalized to obtain tilings that have more than two prototiles. The tilings generated are fractals and their dimensions and the rate of growth are determined.
Extending entity-relationship systems to support hypotheses, constraints, versions, and documents

Abstract EAR-Impish is a database management system (DBMS) that extends the entity-relationship (E-R) concepts and provides its users with several powerful capabilities. It supports integrity constraints representation and data consistency checking. It allows management of time-related concepts and versions of entity and relationship instances. Because it can automatically insert or delete instances, and because it supports definition of demons, EAR-Impish can be considered as an active database system. EAR-Impish also allows the definition and manipulation of hypotheses, a feature that is useful in decision help systems. Finally, it supports documents, which are large attributes, and a simple consistency control of document contents. EAR-Impish characteristics have been specified to fulfil the need for software engineering environments to have adapted and powerful information systems. EAR-Impish fully implements basic E-R concepts, and can be used as an E-R DBMS. However, as it is extended with new concepts, has deductive and automated capabilities, and is coupled with Prolog, EAR-Impish is open and useful to both traditional applications and expert systems. EAR-Impish combines database, file, and logical systems. It implements E-R concepts on top of an extended relational database system, Impish.
Infinite conservation laws for differential systems

We study Lagrangian systems of partial differential equations admitting infinite-dimensional symmetry algebras parameterized by arbitrary functions of dependent variables. We show that these systems have infinite sets of essential conservation laws.
O-Acetylation of Plant Cell Wall Polysaccharides

Plant cell walls are composed of structurally diverse polymers, many of which are O-acetylated. How plants O-acetylate wall polymers and what its function is remained elusive until recently, when two protein families were identified in the model plant Arabidopsis that are involved in the O-acetylation of wall polysaccharides – the reduced wall acetylation (RWA) and the trichome birefringence-like (TBL) proteins. This review discusses the role of these two protein families in polysaccharide O-acetylation and outlines the differences and similarities of polymer acetylation mechanisms in plants, fungi, bacteria and mammals. Members of the TBL protein family had been shown to impact pathogen resistance, freezing tolerance, and cellulose biosynthesis. The connection of TBLs to polysaccharide O-acetylation thus gives crucial leads into the biological function of wall polymer O-acetylation. From a biotechnological point understanding the O-acetylation mechanism is important as acetyl-substituents inhibit the enzymatic degradation of wall polymers and released acetate can be a potent inhibitor in microbial fermentations, thus impacting the economic viability of e.g. lignocellulosic based biofuel production.
A probabilistic approach to the alopex process using moment invariants of images

Summary form only given, as follows. An iterative optimization technique has been developed that uses feedback in order to maximize the response of a system. The cost function for this process is problem dependent and therefore quite flexible. The method has been applied successfully to different optimization problems such as pattern recognition, reception field studies in the visual system of animals, curve fitting, etc. The authors explore the possibility of using probabilities and moment invariants in speeding up the convergence of the process. >
Truncated variants of the GCN4 transcription activator protein bind DNA with dramatically different dynamical motifs.

The yeast protein GCN4 is a transcriptional activator in the basic leucine zipper (bZip) family, whose distinguishing feature is the “chopstick-like” homodimer of alpha helices formed at the DNA-binding interface. While experiments have shown that truncated versions of the protein retain biologically relevant DNA-binding affinity, we present the results of a computational study revealing that these variants show a wide variety of dynamical modes in their interaction with the target DNA sequence. We have performed all-atom molecular dynamics simulations of the full-length GCN4 protein as well as three truncated variants; our data indicate that the truncated mutants show dramatically different correlation patterns. We conclude that although the truncated mutants still retain DNA-binding ability, the bZip interface present in the full-length protein provides important stability for the protein–DNA complex.