cssi/SciSciGPT-SciSciNet huggingface dataset:
Matrix Metalloproteinase-9 Inhibition Attenuates Vascular Endothelial Growth Factor-Induced Intracerebral Hemorrhage

Background and Purpose— Human brain arteriovenous malformation tissue displays increased levels of vascular endothelial growth factor (VEGF) as well as matrix metalloproteinase (MMP)-9, a tissue protease associated with various intracerebral hemorrhage (ICH). We hypothesized that increased MMP-9 was associated with ICH induced by vascular endothelial growth factor hyperstimulation and that this effect could be attenuated by nonspecific MMP inhibition. Methods— We used a mouse model with adenoviral vector-mediated vascular endothelial growth factor transduction in the brain. The association of MMP-9 expression and the brain tissue hemoglobin levels, an index of ICH, after stereotactic injection of adenoviral vector-mediated vascular endothelial growth factor into caudate putamen was assessed. A dose–response study with adenoviral vector-mediated vascular endothelial growth factor and a time course study at both 24 and 48 hours postinjection were performed. Effects of minocycline, a nonspecific MMP inhibito...
Parallel algorithms for message decomposition

Abstract We consider the deterministic and random parallel complexity (time and processor) of message decoding: an essential problem in communication systems and translation systems. We present an optimal parallel algorithm to decompose prefix-coded messages and uniquely decipherable-coded messages in O( n P ) time, using O(P) processors (for all P: 1 ⩽ P ⩽ n/log n) deterministically as well as randomly on the weakest version of parallel random access machines in which concurrent read and concurrent write to a cell in the common memory are not allowed. This is done by reducing decoding to parallel finite-state automata simulation and the prefix sums. We also present an optimal parallel simulation algorithm for finite-state automata using new parallel algorithm design techniques: parallel tree contraction. As a consequence, from the complexity point of view as well as from the data compression point of view, uniquely decipherable coding is better than prefix coding.
A Computer Program to Test a Repeated Measures Hypothesis Using Hotelling's One-Sample T2 Statistic

The extent and direction of bias in an approximate test (TA2) of a one-way repeated measures hypothesis was studied. Monte Carlo methods were used to simulate nine multinormal parent populations. Five thousand samples were drawn from each population and an F statistic (transformed from TA2) was calculated for each sample. Nine sampling distributions, each containing 5,000 Fs, were then observed. TA2 was shown to be very conservative—the proportions observed in the upper tails of the nine distributions were much smaller (in most cases one-half the size) than the proportions expected. The exact T2 test was also presented along with the description of a program which computes this statistic. The program is recommended, over available package programs, because it requires minimum input.
Core polarization effects on spin-dipole and first-forbidden beta -decay operators in the lead region.

The effect of two-particle--two-hole ground-state correlations on spin-dipole transitions and the similar first-forbidden \ensuremath{\beta}-decay transitions is studied for nuclei in the lead region with realistic shell-model interactions. Transitions are considered between states for which one is a particle-hole excitation of the other. It is found that the tensor component of the residual interaction is quite important for the ${0}^{\mathrm{\ensuremath{-}}}$ and ${1}^{\mathrm{\ensuremath{-}}}$ spin-dipole transitions and the analogous \ensuremath{\beta}-decay matrix elements. It is destructive for ${0}^{\mathrm{\ensuremath{-}}}$ and constructive for ${1}^{\mathrm{\ensuremath{-}}}$ so that the quenching of the two modes is quite different. The atypical 1${\mathit{g}}_{9/2}$\ensuremath{\rightarrow}0${\mathit{h}}_{9/2}$ transition is described. The results are compared to previous determinations.
Evaluation of SeaWiFS, MODIS Terra and MODIS Aqua coverage for studies of phytoplankton diurnal variability

Contemporaneous satellite ocean colour data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and MODIS Aqua instruments are consistently calibrated and uniformly processed using equivalent code and algorithms. These sensors cover the globe at different times of a local day. Combining the three instruments provides an unprecedented opportunity to monitor global and local oceanic phytoplankton fluctuations continuously throughout the day. While a daily maximum of 3 hours of coverage is expected from the three sensors, longer observation periods are achieved by combining hourly coverage from a number of consecutive days. The southern hemisphere is then observed continually between 9 am and 3 pm local time. The northern hemisphere is monitored for shorter periods, largely between 10 am and 2 pm local time. This study proposes methodologies to investigate diurnal variability in phytoplankton optical properties from satellite instruments. ...
A New Geophilic Trichophyton

In 1956 an unknown keratinophilic mold was isolated from one of a large collection of soil specimens from New Mexico that was being screened for human pathogenic fungi. The fungus that developed on a soil sample (N.M. 83), that had been baited with hair, produced microconidia and abundant clusters of elongated, smooth-walled macroconidia. The morphology of the spores and the keratinophilic nature of this fungus indicated that it was related to the dermatophytes of the genus Trichophyton. Since only one such isolate was obtained from the 92 soil specimens examined, the organism was given a code number (XI38) and placed in our culture collection. A few years later in 1961, two cultures of what proved to be the same fungus were received from Dr. Geoffry Orr with a note that he had observed the transitory production of Arthroderma-likt cleistothecia. The cultures had been isolated from soil sam? ples collected in the Santa Rosa Indian Reservation (0912) and the Oak Grove Camp Ground (0992) in California. These cultures, X314 and X381, respectively, were also placed in our culture collection. In 1965, 296 soil samples were collected in the desert area of Florence, Arizona, for a coccidioidomycosis project. A portion from each of these soils was baited with bits of horse hair, and a variety of keratino? philic fungi subsequently was isolated. Forty-nine of the isolates proved to be similar to the original New Mexican fungus. In addition, on nine of the soil plates cleistothecia were produced spontaneously. By inoculating portions of the colonies growing on the horse hair bait on tubes of cycloheximide agar (12), pure cultures of all of the isolates were readily obtained. Downy cream-colored, slightly folded colonies were produced on Sabouraud dextrose agar (Fig. 1). The reverse side of the young cultures developed a distinctive yellow pigment (Fig. 2) that turned brownish with age. On slide cultures it was noted that numerous elongated macro? conidia were produced in clusters (Figs. 3-5). These multicellular spores were superncially similar to the linear macroconidia produced
Levator ani abnormality 6 weeks after delivery persists at 6 months

Objective Assess postpartum changes in the levator ani muscle using magnetic resonance imaging and relate these changes to obstetric events and risk factors associated with pelvic floor dysfunction. Study Design A board-certified radiologist specializing in abdominal imaging evaluated 146 pelvic magnetic resonance studies from 57 primiparous women 6 weeks and 6 months after first obstetric delivery and 32 nulliparous women. A yes/no determination of muscle body and insertion integrity, muscle thinning, and measurement of muscle thickness in millimeters was made for each of 4 muscle sites: right and left puborectalis and right and left ileococcygeous. Incidence of muscle abnormality and mean muscle thickness was tested in pairs between (1) nulliparous women and 6-week primiparous women; (2) 6 week and 6 month primiparous pairs; and (3) 3 age/race groups using test of 2 proportions and 1-way analysis of variance. Results Initial review indicated only 3 subjects not of African American or white race, and only 1 African American primiparous woman of age 30 years or older; therefore, statistical analysis was limited to 45 primiparous women and 25 nulliparous women. Incidence of any abnormality at any of the 4 sites was considered abnormal. In those subjects recovering to normal magnetic resonance by 6 months, an average of nearly 60% increase in right puborectalis muscle thickness compared with that seen at 6 weeks indicated the extent of the injury. Subjects with injury to both the puborectalis and ileococcygeous at 6 weeks did not recover to normal at 6 months, whereas those with injury only to the puborectalis tended to have normal magnetic resonance images at 6 months. Conclusion Nulliparity did not guarantee a normal assessment of levator ani anatomy by our blinded reader, and frequency of injury in this series is somewhat greater than that previously reported for primiparous women. Younger white primiparous women had a better recovery at 6 months than older white women. Subjects experiencing more global injury, in particular to the ileococcygeous, tended not to recover muscle bulk.
Tensile deformation and failure processes of amine-cured epoxies☆

Abstract Evidence is reviewed for the occurrence of microscopic flow under tensile loads in a variety of amine-cured epoxies. The nature of the deformation and failure processes involved in these flow processes are discussed. The slow-crack growth fracture topographies of these epoxies, fractured as a function of temperature and strain-rate, are reviewed, and consist of a rough initiation region, that can contain microvoids and/or fractured fibrils, surrounded by a smooth temperature and strain-rate dependent region. These topographical features are explained by initial course craze formation followed by crack propagation through the craze midrib. The crack then imposes a higher stress field on the craze tip which produces a small plastic zone that results in a smooth fracture topography. Fracture topographies also indicate that shear band propagation can occur in the fracture initiation process. The ductile mechanical response of many of these epoxies together with direct experimental observations from transmission electron microscopy and birefringence studies produce further evidence that flow can occur in these glasses. Both plastic, homogeneous and inhomogeneous deformations can occur. The inhomogeneous deformations can evolve into macroscopic shear bands. The ability of these crosslinked glasses to undergo microscopic flow is discussed in terms of (i) our understanding of their chemical and physical structure and (ii) covalent bond scission.
Signatures of vibrational interactions in coherent two-dimensional infrared spectroscopy

Abstract The influence of three vibrational interaction mechanisms on two-dimensional (2D) spectra derived from infrared (IR) photon echo experiments is investigated. In particular it is shown that the existence of a nonlinear signal requires one of the following vibrational nonlinearities: (1) anharmonicity in the ground state potential, (2) nonlinear dependence of the transition dipole moment on the vibrational coordinates, or (3) level-dependent dephasing dynamics. 2D spectra arising from these interactions are investigated using a model of two coupled cubic anharmonic oscillators. The third-order nonlinear response for this model arises from 20 different vibronic coherence pathways involving six possible vibrational states. It is shown that the three interaction mechanisms are revealed by distinct signatures in the 2D spectrum: the positions, amplitudes, and shape of peaks, respectively. These signatures provide an intuitive framework for the analysis of 2D IR spectra.
An evaluation of the interaction of morning residual layer and afternoon mixed layer ozone in Houston using ozonesonde data

The Tropospheric Ozone Pollution Project (TOPP) launched >220 ozonesondes in Houston (July 2004– June 2008) providing examples of pollution transported into, re-circulated within, and exported from the Houston area. Fifty-one launches occurred during the Texas Air Quality Study (TexAQS) II and the summer portion of IONS-06 (INTEX [Intercontinental Transport Experiment] Ozonesonde Network Study). On 11 days during TexAQS II and on 8 other occasions, ozonesondes were launched both at dawn and in the afternoon. Analysis of these ‘‘intensive’’ launch sequences shows that morning residual layer (RL) ozone concentrations ([O3]) explained 60–70% of the variability found in the afternoon mixed layer (ML). Furthermore, maximum RL [O3] is nearly identical to the mean ML [O3] from the previous afternoon (morning minus afternoon ¼� 1.6 � 8.4 ppbv). During TexAQS II, mean [O3] below 1.3 km (the mean ML height from ozonesonde data) increased from 37 � 22 ppbv in the morning to 74 � 18 ppbv in the afternoon, suggesting an average net local daily O3 production of w500–900 tons over the metropolitan Houston area.
Uniqueness of a model of steady-state groundwater flow

Abstract The main objective of this study was to investigate some of the methods and conditions necessary to determine bounds on values of the hydrogeologic parameters which characterize a model of steady-state areal near-surface groundwater flow. The basic tool selected to accomplish the research objectives was the optimization approach to determining the parameters. With this approach the parameters are calculated by minimizing some selected objective function composed of a measure of the difference between observed and computed heads. Several methods were investigated for possible use, and modifications of the ones by Coats et al. and Yeh and Tauxe were selected for comparison. The results of application of the Coats et al. method to several test problems and a field area indicate that occasional large errors may occur even when the input data (water levels and constraints on parameters) are very good, and that when the data are subject to various errors, as is the case for the Truckee Meadows data, the method is unreliable. Application of a modified version of the Yeh and Tauxe method to test problems and Truckee Meadows, Nevada, yielded much better results than did the method of Coats et al. There is no unique set of parameters which produce a distinct minimum error (defined as the sums of squares of the differences between computed and observed hydraulic heads) for the Truckee Meadows data. The apparent minimum error occurs for transmissivity which is constant throughout the valley. This appears to conflict with the geological and driller's log evidence that show the existence of zones of differing average hydraulic conductivity (and presumably transmissivity). However, some of the parameters can be changed over a large range and the error is not materially affected. Thus, the system is not well determined by the “optimum” parameters and other combinations of parameters, including combinations that satisfy the geological constraints, yield solutions that are almost as good. The failure of the water-level data to provide a definite optimum solution which conforms to the geological evidence may be due at least in part to the basic methods normally used to construct water-level maps. By changing the positions and configurations of contours within logical limits, it would be possible to turn recharge or discharge areas into adjacent zones of differing transmissivity and vice versa. Data collection and use of a reliable parameter estimation method are complementary. Early, preliminary computation of parameters in a study would indicate areas where data are contradictory or inadequate and where additional critically placed data should be collected. Repeated application of this process should result in a more efficient expenditure of time and money than occurs for the more traditional approach where the model is applied at a late stage in the study.
Effects of chronic shock on cooperation: a potential model of learned chronic pain behavior.

Summa~y.-Pain, as a private experience, cannot be measured directly; it can only be inferred from pain-associated behaviors. An objective measure of such behavior is the observable impairment of functioning, e.g., a reduction in performance. It has been suggested that pain behaviors can eventually cease to be a function of neural activity and come under the control of external environmental contingencies. In an initial attempt to test this suggestion, pairs of rats were housed separately in chambers for the duration of the experiment. Their normal activity in this condition included lever-pressing for food on a cooperative schedule of reinforcement. The ratio of responses showed the division of labor. The grid floor of one chamber was then electrified at low amperage, reducing the proportion of responses made by that subject. This reduction was complemented by an increase in the amount of responding by the partner. Following termination of shock, baseline ratios were slow to recover, demonstrating chronically impaired functioning. These results support Fordyce's suggested etiology of chronic pain behaviors in humans. Chronic pain is one of the most costly health care problems in the United States today (Turk, Meichenbaum, & Genest, 1983). Whereas acute pain is characterized by its temporal limit and temporary disruption of lifestyle, chronic pain is quite different. The changes in lifestyle engendered by chronic pain tend to be systematic and relatively permanent. In many cases, the role of primary breadwinner may even be passed to another member of the family (Fordyce, 1976).
Correlates of Race and Substance Abuse with Religious Support Systems: A Study of Pregnant Substance Abusers

Women who misuse substances may have decreased connections with community structures, including religious support systems. This study examined the correlates of race, age, socioeconomic status, and drug use status on 1,116 pregnant women's connections with religious support structures. Data were derived from the 2002 National Survey of Drug Abuse and the 2003 National Survey of Drug Use and Health and were used to perform a secondary analysis of the variables. Results of the analyses revealed that race is not an indicator of social connectivity; while drug use, age, and socioeconomic status are indicators.
Simulation of Global Land Surface Conditions from 1948 to 2004. Part I: Forcing Data and Evaluations

Abstract Because of a lack of observations, historical simulations of land surface conditions using land surface models are needed for studying variability and changes in the continental water cycle and for providing initial conditions for seasonal climate predictions. Atmospheric forcing datasets are also needed for land surface model development. The quality of atmospheric forcing data greatly affects the ability of land surface models to realistically simulate land surface conditions. Here a carefully constructed global forcing dataset for 1948–2004 with 3-hourly and T62 (∼1.875°) resolution is described, and historical simulations using the latest version of the Community Land Model version 3.0 (CLM3) are evaluated using available observations of streamflow, continental freshwater discharge, surface runoff, and soil moisture. The forcing dataset was derived by combining observation-based analyses of monthly precipitation and surface air temperature with intramonthly variations from the National Center...
HOMOTOPY CLASSES FOR STABLE CONNECTIONS BETWEEN HAMILTONIAN SADDLE-FOCUS EQUILIBRIA

For a class of Hamiltonian systems in ℝ4 the set of homoclinic and heteroclinic orbits which connect saddle-focus equilibria is studied using a variational approach. The oscillatory properties of a saddle-focus equilibrium and the variational nature of the problem give rise to connections in many homotopy classes of the configuration plane punctured at the saddle-foci. This variational approach does not require any assumptions on the intersections of stable and unstable manifolds, such as transversality. Moreover, these connections are shown to be local minimizers of an associated action functional. This result has applications to spatial pattern formation in a class of fourth-order bistable evolution equations.
Homoepitaxy of 6H-SiC by solid-source molecular beam epitaxy using C60 and Si effusion cells

Abstract High quality homoepitaxial 6H-SiC films have been grown by solid-source molecular beam epitaxy (MBE) using C 60 and Si effusion cells. Scanning electron micrographs show terraced surfaces indicative of step-flow growth. Cross-sectional transmission electron microscopy results demonstrate extremely good epitaxial growth with no hint of dislocations, double-positioning boundaries, or 3C inclusions. We believe this is the first report of homoepitaxy of 6H-SiC using C 60 and the first instance of silicon carbide (SiC) epitaxy using a Si effusion cell in the evaporation rather than the sublimation mode. This combination of solid-source MBE and determination of appropriate growth conditions have led to superior homoepitaxial growth of 6H-SiC.
Social categories are shaped by social experience

A new study by Rhodes and colleagues offers insight into the development of social essentialism – the belief that members of social categories share essential properties (e.g., attitudes, psychological capacities). The challenge now is to consider these issues in children raised in the more diverse social environments that constitute the range of human experience.
Efficient targeted transduction of primary human endothelial cells with dual-targeted lentiviral vectors.

Angiogenesis is a rate-limiting factor for numerous human diseases. Angiogenic vessels and also the endothelium of certain organs such as the lung display molecular addresses that can be exploited for the selective delivery of gene therapeutics. Lentiviral vectors (LVs) are powerful tools for stable gene delivery but their integration and expression in undesired cell types poses a serious safety concern. We have developed a dual-targeted LV that can specifically target primary endothelial cells (ECs). Cell selectivity is achieved during entry, using a modified Sindbis virus envelope, and during transcription, with an EC-specific promoter. We evaluated four surface markers for EC targeting and seven promoter sequences from genes preferentially expressed in ECs. The efficiency and specificity of the double targeted vector were assayed in a panel of human primary cultures and tumor cell lines. A vector targeted to CD146, an endothelial adhesion molecule, and carrying a derivative of the EC tyrosine kinase Tie2 promoter, increased specificity of transduction up to 50 times and was also effective at selectively transducing ECs in a mixed coculture with human fibroblasts. The vector presented here is a potentially powerful tool that could be used in a variety of human diseases. Copyright © 2007 John Wiley & Sons, Ltd.
The Effect of Test Reporting on Self-Estimates of Scholastic Ability and on Level of Occupational Aspiration

AbstractA major assumption underlying: the interpretation of test results to pupils is that the individual receiving: the test report will use the information wisely in making: appropriate occupational choices. This study sought to determine whether test reporting: could be used to validate this assumption by observing: the status of aspiration levels among: students who made significant increases in knowledge of their scholastic ability. A pretest-posttest control group design was employed In which 41 eleventh grade public school pupils who received test reports of their scholastic ability were compared on self-knowledge and occupational aspiration level with 30 pupils who did not receive reports of their scholastic ability. Although pupils who received test reports made significant gains In self-knowledge, there were no significant changes In occupational aspiration levels. The findings suggest that information about scholastic ability only is not sufficient to bring about changes In occupational aspira...
Racial and Ethnic Disparities in Pediatric Appendicitis Rupture Rate

Objectives: To determine if there are racial/ethnic differences in the rates of appendiceal rupture among the children of two large states. Because rupture is primarily due to delayed diagnosis, differences would suggest disparities in timely access to quality emergency care. Methods: This was an observational, cross-sectional analysis of full-year samples of acute appendicitis cases from California and New York children 4 to 18 years old. Racial/ethnic groups were compared for risk of appendiceal rupture adjusted for biological factors both before and after adjustment for the following socioeconomic, hospital, and admission characteristics: income, insurance, hospital type, and admission source. Results were interpreted in light of census data on the proportion of immigrants in each racial/ethnic group. Results: Compared with white children with acute appendicitis, Hispanic and Asian children have higher odds of rupture in California, whereas Asian and black/African American children have higher odds in New York. These differences roughly parallel the within-state proportion of immigrant children in these groups. Adjustments for family, socioeconomic, and hospital characteristics attenuate but do not eliminate disparities. Conclusions: The authors found evidence of significant racial/ethnic disparities in rate of appendiceal rupture, an important and preventable outcome, in two large but dissimilar states. Immigrant groups may be most at risk for delayed emergency care. Future research should focus on immigration and acculturation as risk factors for appendicitis rupture in children.
Heterogeneous Expression of Chondroitin Sulfate Glycosaminoglycans and Versican Proteoglycan during Early Development of Rathke’s Pouch

While much is known regarding morphogenetic factors involved in specification and differentiation of Rathke’s pouch, less attention has been given to extracellular matrix (ECM) interactions involved in its formation. The present research investigated localization of two different chondroitin sulfate glycosaminoglycans (CS-GAGs), TC2 and d1C4, and versican CS-proteoglycan (PG) to identify additional ECM molecules involved in formation of the pituitary rudiment. Immunohistochemical evaluation of anterior pituitary primordia between HH15 and HH28 showed these ECM molecules prevalent in basement membrane and surrounding ECM underlying Rathke’s epithelia and to a lesser extent between pouch epithelial cells. TC2/d1C4 CS-GAGs and versican showed changing and heterogeneous localization during pouch development that suggested specific roles in cell-ECM interaction during pituitary morphogenesis. TC2 antigen colocalized with versican at early stages in an asymmetric pattern, with particularly strong staining between ventral diencephalon and roof of Rathke’s pouch while d1C4 CS-GAG encompassed the entire pouch by HH22 indicating association with a different CSPG. The heparan sulfate proteoglycan, perlecan, used to verify basement membrane structure, was a consistent component of Rathke’s pouch. Data show a dynamic and heterogeneous pattern of CS-GAG and versican expression during early chick Rathke’s pouch development that suggests new possibilities for ECM function in its establishment and growth.
Inhibition of experimental melanin protein-induced uveitis (EMIU) by targeting nitric oxide via phosphatidylcholine-specific phospholipase C.

Experimental melanin protein-induced uveitis (EMIU) is an autoimmune uveitis induced by immunization with uveal melanin protein. Fas and FasL enhancement is reported in rats with EMIU. Tricyclodecan-9-yl-xanthogenate (D609), a specific inhibitor of phosphatidylcholine-specific phospholipase C, inhibits inducible nitric oxide synthase (iNOS) induction. In two independent experiments, 35 Lewis rats with EMIU received either D609 or PBS daily. The eyes and draining lymph nodes were collected for histology, analyses of nitrite, peroxide, and superoxide dismutase, Fas and FasL immunochemistry, in situ hybridization for iNOS mRNA and in situ apoptosis detection at the peak of the disease. Both experiments showed significant inhibition of EMIU by D609. Decreases in nitrite and peroxide, increase of superoxide dismutase and lower expressions of iNOS mRNA were found in D609-treated, as compared to PBS-treated eyes. There was mild enhancement of Fas and FasL in the eyes and lymph nodes of D609-injected animals. DNA fragmentation was increased in the lymph nodes of D609-treated rats. We conclude that iNOS activation is responsible for NO production in eyes with EMIU. The suppressive effect of D609 on EMIU may result from scavenging NO and activating apoptosis previously inhibited by NO along with other anti-inflammatory effects.
Magnetic nanoparticles for tunable microwave metamaterials

Commonly, metamaterials are electrically engineered systems with optimized spatial arrangement of subwavelength sized metal and dielectric components. We explore alternative methods based on use of magnetic inclusions, such as magnetic nanoparticles, which can allow permeability of a composite to be tuned from negative to positive at the range of magnetic resonance. To better understand effects of particle size and magnetization dynamics, we performed electron magnetic resonance study on several varieties of magnetic nanoparticles and determined potential of nanoparticle use as building blocks for tunable microwave metamaterials.
Gangs of America: The Rise of Corporate Power and the Disabling of Democracy

A review is presented of the book “Gangs of America: The Rise of Corporate Power and the Disabling of Democracy,” by Ted Nace.
Operational Work Pattern Discovery Based on Human Behavior Analysis

This paper presents a human behavior analysis model combining process discovery and decision tree analysis. The proposed analysis model uses the event log traces generated by enterprise sales applications, which are mainly used by salespeople. We verify the effectiveness of the proposed approach using scenario-based simulation and find that our proposed approach is robust against randomly generated activities. We also present that important work behavior patterns can be discovered using the process discovery technology by checking higher frequency transitions.
Out of sight, out of mind: high cryptic diversity obscures the identities and histories of geminate species in the marine bivalve subgenus Acar

Aim The rise of the Isthmus of Panama and the formation of ‘geminate’ species pairs serves as an important model of allopatric speciation. However, to function as a model system, hypothesized geminates must first be shown to be each other’s closest living relatives. If the presence of cryptic taxa obscures true relationships, the biogeographical histories of transisthmian taxa are likely to be misinterpreted. We have therefore completed a phylogeographic survey of the transisthmian bivalve subgenus Acar in the genus Barbatia to characterize patterns of tropical American diversity and to place transisthmian taxa in a regional phylogeographic context. Location Tropical America. Methods Mitochondrial cytochrome c oxidase I (COI) and nuclear internal transcribed spacer (ITS) sequences were obtained from 233 specimens of Acar. Sequences were analysed using cladistic and Bayesian methods. Divergence times between species were inferred from net nucleotide divergences and a coalescence-based method. Results The survey revealed 22 COI clades that were also monophyletic at ITS, indicating that the taxonomy of Acar is potentially greater than a fivefold diversity underestimate. The lone previously recognized geminate [Barbatia (Acar) gradata and Barbatia (Acar) domingensis] is composed of 15 clades. Among the four transisthmian lineages identified, two diverged more than 14 Ma; the two other geminates split just prior to the time of final seaway closure. In addition to a fourfold increase in the number of known geminates, our data show that within-basin diversification has been more impressive, with one geminate splitting into five monophyletic clades in the Western Atlantic alone since seaway closure. Electron microscopy of the larval shells of specimens indicates that the transisthmian lineage with the greatest rate of post-Isthmian diversification possesses non-planktonic larvae, a life-history feature linked to high speciation rates. Main conclusions Our analyses revealed that the identities of geminate pairs split by the Isthmus of Panama were obscured by extremely high tropical American cryptic diversity. Although we have identified four geminates, only two appear to have been split by the Isthmus. Our uncovering of extensive post-Isthmian diversification is consistent with the palaeontological perspective that the final closure of the Central American Seaway was followed by high rates of subgeneric diversification, particularly in the tropical Western Atlantic.
Fuel oils from euphorbs and other plants

Fuel oils from Euphorbs and other plants. The increasing energy costs of finding petroleum, together with the sure knowledge that its supply is finite, has prompted us to seek other sources of liquid hydrocarbon for both fuel and material. We have turned to annually renewable plant sources such as seed oils, an obvious source, with palm oil as the most productive. Sugar cane used to produce ethanol is another fuel source already in use. We have examined non-food plants which can be grown on marginal soil for their productivity, particularly the genus Euphorbia. All species of this genus produce a latex which can be converted into useful fuel and other material, including precursors for what might be a valuable anti-tumor agent. Euphorbias and other similar plants require repeated planting and harvesting of the entire plant, which constitutes a drain on the soil. Trees can be long-term sources for hydrocarbon-like materials with a single planting. Examples are: the genus Copaifera which can be tapped for sesquiterpenes, the genus Pittosporum which bears fruits rich in terpenes and can be harvested annually. Finally, there are algae whose oil productivity is already of interest. It seems possible to modify genetically the terpene biosynthetic pathways in plants to improve both the quality and quantity of the oils produced from them.
Pre-inversion Corrections and Analysis of Radar Tomographic Data

Pre-inversion corrections and analysis of transmission radar data is important for producing reliable tomographic images. In order to extract high-resolution, quantitative information from radar tomographic data, it is important to process the data as accurately as possible. This is especially true when analyzing data collected in a time-lapse mode, where changes in geophysical attributes with time may be less than a few percent, or when the spacing between acquisition wells is on the order of several meters. Using high-resolution tomographic radar data collected in a variety of geological environments, this study illustrates how different pre-inversion travel time and amplitude processing steps affect the velocity and attenuation estimates. In some cases, the distortion caused from incorrect processing can lead to severe artifacts in the tomogram including the appearance of anisotropy. This paper presents methods for recognizing and correcting the raw data for errors caused by incorrect station geometry ...
Applications of operational transconductance amplifier in power system analog emulation

The application of operational transconductance amplifiers (OTAs) in analog emulation of power systems in the form of a power system on a chip (PSoC) is explored. Sub-circuits in the PSoC have been developed with OTAs, which make a reconfigurable analog emulator realizable. In addition, simulation results using Spice highlight important characteristics of the OTAs in the sub-circuits.
Study of a thermotropic liquid-crystalline polyester at elevated pressures

A thermotropic liquid-crystalline copolyester of 20% hydroxybenzoic acid, 40% isophthalic acid, and 40% hydroquinone polymer was studied at elevated pressures. The characterization techniques at elevated pressures (0–1000 bar) included high-pressure differential thermal analysis and dilatometry; at atmospheric pressure, differential scanning calorimetry, thermal optical analysis, and x-ray analysis were employed. The mechanical properties of the solid specimens prepared at different pressures were studied by compression and dynamic rotation mechanical testing techniques. High-pressure induced a new crystal habit in the solid state and a new mesophase in the melt. These transitions are summarized in a proposed phase diagram. Mechanical tests on the material produced at elevated pressure indicate the possibility of improved properties, implying that the pressure-dependent morphological changes in thermotropic copolyesters could be of practical significance. The finding of a pressure-induced mesophase also confirmed the possibility of extending the range of polymers which might exhibit liquid crystallinity via the application of pressure.
Popcorn lung and bronchiolitis obliterans: a critical appraisal

Purpose To perform a critical review of a series of journal articles and Health Hazard Evaluation Reports (HHER) by the National Institute for Occupational Safety and Health (NIOSH), where they have described the incidence of fixed obstructive pulmonary disease in a population of workers exposed to butter flavorings.
Simulating Lyme disease using parallel discrete event simulation

Lyme Disease affects many people in the northeastern United States. One of the most important mech anisms that sustains the epidemic is the interaction between white-footed mice (Peromyscus leuco pus) and deer ticks (Ixodes scapularis). When mice move around in their territory they carry diseased ticks to new locations. Our system simulates the different developmental stages of the tick through its active spring/summer period. The system uses the optimistic protocol for Parallel Discrete Event Simulation. In this paper, we present the model of the spread of the disease. We describe how we parallelize the problem, and we sketch a new global virtual time algorithm used in our system. We present performance benefits resulting from a parallel platform.
Motion parameter estimation of multiple ground moving targets in multi-static passive radar systems

Multi-static passive radar (MPR) systems typically use narrowband signals and operate under weak signal conditions, making them difficult to reliably estimate motion parameters of ground moving targets. On the other hand, the availability of multiple spatially separated illuminators of opportunity provides a means to achieve multi-static diversity and overall signal enhancement. In this paper, we consider the problem of estimating motion parameters, including velocity and acceleration, of multiple closely located ground moving targets in a typical MPR platform with focus on weak signal conditions, where traditional time-frequency analysis-based methods become unreliable or infeasible. The underlying problem is reformulated as a sparse signal reconstruction problem in a discretized parameter search space. While the different bistatic links have distinct Doppler signatures, they share the same set of motion parameters of the ground moving targets. Therefore, such motion parameters act as a common sparse support to enable the exploitation of group sparsity-based methods for robust motion parameter estimation. This provides a means of combining signal energy from all available illuminators of opportunity and, thereby, obtaining a reliable estimation even when each individual signal is weak. Because the maximum likelihood (ML) estimation of motion parameters involves a multi-dimensional search and its performance is sensitive to target position errors, we also propose a technique that decouples the target motion parameters, yielding a two-step process that sequentially estimates the acceleration and velocity vectors with a reduced dimensionality of the parameter search space. We compare the performance of the sequential method against the ML estimation with the consideration of imperfect knowledge of the initial target positions. The Cramer-Rao bound (CRB) of the underlying parameter estimation problem is derived for a general multiple-target scenario in an MPR system. Simulation results are provided to compare the performance of the sparse signal reconstruction-based methods against the traditional time-frequency-based methods as well as the CRB.
Impact of Sea Surface Temperature and Soil Moisture on Summer Precipitation in the United States Based on Observational Data

Thisstudyexaminestheimpactofseasurfacetemperature(SST)andsoilmoistureonsummerprecipitation over two regions of the United States (the upper Mississippi River basin and the Great Plains) based on data from observation and observation-forced model simulations (in the case of soil moisture). Results from SST‐ precipitation correlation analysis show that spatially averaged SST of identified oceanic areas are better predictors than derived SST patterns from the EOF analysis and that both predictors are strongly associated with the Pacific Ocean. Results from conditioned soil moisture‐precipitation correlation analysis show that the impact of soil moisture on precipitation differs between the outer-quartiles years (with summer precipitation amount in the first and fourth quartiles) and inner-quartiles years (with summer precipitation amount in the second and third quartiles), and also between the high- and low-skill SST years (categorized according to the skill of SST-based precipitation prediction). Specifically, the soil moisture‐precipitation feedbackismorelikelytobepositiveandsignificantintheouter-quartilesyearsandintheyearswhentheskill of precipitation prediction based on SST alone is low. This study indicates that soil moisture should be included as a useful predictor in precipitation prediction, and the resulting improvement in prediction skills will be especially substantial during years of large precipitation anomalies. It also demonstrates the complexity of the impact of SST and soil moisture on precipitation, and underlines the important complementary roles both SST and soil moisture play in determining precipitation.
What do family physicians believe and value in their work

Background: Family practice has always valued physician self-awareness. Whereas self-awareness has traditionally focused on problem relationships with patients, generally unexplored are the physicians9 personal beliefs and values that strongly influence their routine clinical work and collegial relationships. Thus we know little about the nature and scope of these beliefs and values. The following study was undertaken to foster a better understanding of beliefs and values that residents bring to their clinical practice. Methods: Applying 13 years of experience with one method of structured reflection and conversation, I was able to perform a cross-set analysis of findings from interactions with 143 family practice residents. Such dimensions as views of life and death, role of physician, and process of healing served as avenues to elicit beliefs and values. Results: The residents9 responses yielded the following six themes: philosophy and spirituality, the nature of suffering, the strains of helping, the healing relationship, the coherence of models, and clashes with the models of patients and colleagues. Conclusion: These conversations with family physicians-in-training suggest that they bring to their clinical and collaborative relationships complex, highly personal models of medicine that emphasize meaning and human relationship and serve as a source of strength. To better understand these models, future work should investigate the general beliefs and values of experienced family physicians in various practice settings, how their models of medicine interact and perhaps clash with those of their patients and colleagues, and effective methods for helping family physicians articulate their views so they can function effectively in their clinical practice.
Effects of UV‐B Radiation on Anti‐predator Behavior in Three Species of Amphibians

Ultraviolet radiation has been suggested as a possible contributing cause of amphibian declines around the world. Both laboratory and field studies have demonstrated that exposure to ultraviolet radiation can lead to increased mortality of developing amphibians. Virtually no studies have examined the sub-lethal effects of ultraviolet on amphibian behavior. In this study, we examine the anti-predator behavior of three species of amphibians after short-term exposure to ultraviolet-B radiation. Toad (Bufo boreas) juveniles that had been exposed to ultraviolet radiation did not respond to chemical extracts from conspecifics and heterospecifics as much as juveniles that had not been exposed. Both newt larvae (Taricha granulosa) that had been exposed to ultraviolet radiation and those that had not been exposed responded to chemical cues from conspecific predators by increasing the amount of time spent in shelter. Frog tadpoles (Rana cascadae) that had been exposed to ultraviolet radiation did not reduce their movement in response to chemical cues from predators as much as tadpoles that had not been exposed. These results indicate that ultraviolet exposure may have important sub-lethal effects in amphibians that could adversely effect their fitness.
POPULATION STRUCTURE AND GENETIC DIVERSITY OF BOTRYCHIUM PUMICOLA (OPHIOGLOSSACEAE) BASED ON INTER-SIMPLE SEQUENCE REPEATS (ISSR)'

Species of Botrychium reproduce by spores that form subterranean gametophytes and a few, like B. pumicola, also reproduce asexually with subterranean sporophytic gemmae. The goal of this study was to examine the genetic diversity of B. pumicola populations and to better understand the role of gemmae. Ninety-nine individuals from three monitored populations were sampled. The technique of inter-simple sequence repeats (ISSR) produced 15 polymorphic loci and identified 71 ISSR genotypes. Sixteen of the ISSR genotypes were shared by more that one individual in a population, representing potential clones. Ten of the 16 shared genotypes were not limited to clusters of plants (groups of plants growing from the same point). The ten potential clones were disjunct (separated by other genotypes) and not in patches as might be expected for an underground propagule. There is a high probability that these shared genotypes arose from independent sexual events suggesting they were not clones. These results suggest that the long-distance dispersal of gemmae is at best a rare event.
Complex effects of molecular topology on diffusion in entangled biopolymer blends

By combining single-molecule tracking with bond-fluctuation model simulations, we show that diffusion is intricately linked to molecular topology in blends of entangled linear and ring biopolymers, namely DNA. Most notably, we find a previously unreported non-monotonic dependence of the self-diffusion coefficient for linear DNA on the fraction of linear DNA comprising the ring-linear blend, which we argue arises from a second-order effect of ring DNA molecules being threaded by varying numbers of linear DNA molecules. Results address several debated issues regarding molecular dynamics in biopolymer blends, which can be used to develop novel tunable biomaterials.