cssi/SciSciGPT-SciSciNet huggingface dataset:
Higher fluctuating asymmetry as a measure of susceptibility to pesticides in fishes

Two species of fishes common to the Great Plains of North America (the western mosquitofish [Gambusia affinis] and the sand shiner [Notropis ludibundus]) were used to examine the relationship between individual time-to-death (TTD) in 96-h toxicity tests and average fluctuating asymmetry (FA). Previous studies have indicated that FA, the random deviation from bilateral symmetry in metric traits, is increased in organisms that develop in stressful and/or marginal environments. This association has led to the prediction that FA may be useful as a bioindicator. For example, if an individual's FA is negatively related to stress resistance, a population that has comparatively high values of FA may be more susceptible to further stressors. Adult fish used in these experiments were captured from natural populations in Kansas and acclimated to laboratory conditions for 1 month before use in toxicity tests. Each species was separately exposed to two insecticides: parathion, an organophosphate, and lindane, an organochlorine. For each TTD test, 200 individuals were exposed over a 96-h period to an LC70 concentration. Dead individuals were removed every 3 h. Individuals that survived the test were sacrificed for comparison to those that died. Measurements for seven external morphologic characters were obtained for each individual and used to estimate average FA. Three of four statistical tests showed a significant negative regression between TTD and average FA, indicating that individuals with smaller FA survived longer in the test conditions. These results support the use of FA as an indicator of susceptibility to pesticides.
Characterization of copper layers produced by cold gas-dynamic spraying

The cold gas-dynamic spray method produces coatings or deposits by introducing solid feedstock particles into a supersonic gas stream developed through the use of a converging-diverging (de Laval) nozzle. The particles thus accelerated impact on a substrate surface and develop into a dense deposit through a process believed to be similar to cold compaction. The work reported here explores the internal nature and physical characteristics of copper deposits produced by the cold gas-dynamic spray method using two vastly different starting powders: in one case, a “spongy” copper obtained by a direct-reduction process, and in the second, a denser, more spheroidal particulate produced by gas atomization. Optical and electron microscopies (scanning electron microscopy [SEM] and transmission electron microscopy [TEM]) were used to observe details of microstructure in the feedstock particles and deposits. Young’s modulus and residual stress measurements for the deposits were obtained through mechanical means, and measurements of hardness and electrical conductivity are reported. The internal structure of the cold-spray deposit was influenced by the surface purity of the feedstock material.
The Impact on Patient Health Outcomes of Interventions Targeting the Patient-Physician Relationship

Over the past 3–4 decades, numerous studies have been published evaluating interventions targeted at healthcare providers, at patients, or at both patients and healthcare providers, which are designed to, in some fashion, improve the provider-patient relationship and thereby enhance patient health outcomes. This article synthesizes findings from 14 literature reviews of relevant studies published between 1991 and 2007. Findings indicate that interventions aimed at physicians and other providers have consistently produced positive effects on provider communication behaviors and interpersonal skills. However, only moderately positive effects on patient satisfaction, and limited impact on patient healthcare behaviors such as compliance, appointment adherence, and resource use were found. Effects on primary medical outcomes were minimal although some positive effects on secondary medical outcomes such as quality of life were obtained. Patient-targeted interventions also showed consistently positive effects on patient-physician communication in addition to enhanced patient participation in decision making. Effects on patient primary medical outcomes were limited, and weak effects on patient satisfaction were obtained. Characteristics of studies and training programs that may have influenced outcomes are discussed, as are practical impediments to promoting better physician-patient communication in clinical practice.
A note on the cross-covariance operator and on congruence relations for Hilbert space valued stochastic processes

Explicit formulas are derived for the congruence mappings that connect three Hilbert spaces associated with a second-order stochastic process. In particular, an insightful expression is obtained for the mapping that connects a process to its corresponding reproducing kernel Hilbert space. In addition, a useful infinite dimensional extension of a result from Khatri (1976) which pertains to cross-covariance operators is provided.
Application of genetic algorithm for optimum design of bolted composite lap joints

The genetic algorithm (GA), a powerful optimization technique for multiple extrema functions in multidimensional search spaces, is applied in conjunction with stress analysis to achieve optimum designs of bolted composite lap joints. The objective of the optimization is to ensure the highest strength of the joint. In this study, the laminate thickness, laminate lay-up, bolt location, bolt flexibility, and bolt size are considered as design variables. The contact stresses (bolt loads) are determined by a combined complex potential and variational formulation. In this formulation, the equilibrium equations are satisfied exactly and the boundary conditions are enforced by minimizing the total potential. The contact stresses as well as the contact region are determined through an iterative procedure as part of a solution method that accounts for the effects of finite geometry and by-pass loading. The fitness function for the GA optimization is based on the average stress failure criterion for predicting net-section, shear-out, and bearing failure modes in bolted lap joints.
On The Planning Of Non-Linear Collision-Free Robot Paths

The paper describes an approach to collision-free robot motion when the robot motion is assumed to be non-linear. The paper concentrates on the planar case.
Interventions for Hispanic Caregivers of Patients with Dementia: A Review of the Literature

Background: The number of Hispanics/Latinos living with dementia in the United States is expected to rise from 200,000 to 1.3 million by 2050, which will result in large numbers of Hispanics/Latino...
Intussusception of the reconstructed bladder neck leads to earlier continence after radical prostatectomy.

Abstract Introduction. Although there is no evidence that the reconstructed bladder neck actively contributes to post-radical prostatectomy continence, we set out to determine whether buttressing sutures, which prevent the bladder neck from pulling open as the bladder fills, would result in the earlier return of urinary control. Technical Considerations. Forty-five men (mean age 57 years, range 37 to 67) with clinical localized prostate cancer underwent anatomic radical retropubic prostatectomy with standard tennis racket bladder neck reconstruction. The bladder neck was then intussuscepted using two 2-0 Maxon Lembert sutures placed lateral and posterior to the reconstructed bladder neck. Filling of the bladder with saline at this point revealed little leakage. Patient-reported continence at 3 months was compared with the published outcome of 64 men using the same quality-of-life instrument (the UCLA Prostate Cancer Index). At 3 months, 82% of men who underwent intussusception of the bladder neck were continent (no pad/dry pad) compared with 54% in our prior report ( P = 0.0035). The occurrence of bladder neck contracture was similar: 7% versus 5%. Conclusions. Intussusception of the bladder neck led to a significant improvement in urinary control at 3 months postoperatively. Longer follow-up will be necessary to determine whether this approach may eliminate the 2% probability of long-term significant problems with urinary control.
Effects of axial magnetic field on mhd instabilities in cylindrical liners

This paper analyzes the effects of an axial magnetic field on the magneto-Rayleigh-Taylor instability (MRT) of an imploding cylindrical liner. In recent MagLIF experiments with a premagnetized axial magnetic field [1], helical perturbations on the outer surface of the liner were found to persist despite the severe winding up of the magnetic field streamline. The inner surface of the liner exhibited improved integrity as a result of the premagnetized axial magnetic field. Here, we propose that the helical structure is the signature of the azimuthal m = 1 eigenmode with axial wavenumber k, so that the pitch angle of the helix, phi = arctan(m/kr) ∼ 1/kr. Here, r is the outer radius of the imploding liner at which the helical perturbations were observed [1]. This simple scaling shows that phi increases as the convergence ratio (CR) increases, i.e., as r decreases. It also qualitatively explains the evolution of phi in both the low CR and high CR shot data that were tabulated in [1]. We have extended our MRT theory for the slab geometry [2] to a cylindrical geometry, so as to include the coupling between MRT, the sausage mode (m = 0) and the kink mode (m = 1). The effect of feedthrough suppression by the strong axial magnetic field is noted. Instantaneous equilibrium profiles obtained from 1-D HYDRA runs have been applied to the aforementioned formulation.
Serious psychological distress among persons with epilepsy based on the 2005 California Health Interview Survey.

SUMMARY Purpose: To compare the prevalence of selfreported serious psychological distress using the Kessler 6 (K6) in persons with a history of epilepsy (PWE) to those without epilepsy from a population-based survey. Methods: Data were analyzed from adults aged ‡18 years (n = 43,020) who participated in the 2005 California Health Interview Survey (CHIS). Results: California adults with a history of epilepsy, after controlling for demographics and comorbidities, reported higher rates of feeling nervous [odds ratio (OR) 2.22], feeling hopeless (OR 1.35), feeling restless (OR 2.07), feeling depressed (OR 3.14), and feeling worthless (OR 2.57), and reported that everything has been an effort (OR 2.28) in the last 30 days. The K6 score showed that serious psychological distress is more common in PWE (OR 2.24). After adjusting for demographics, comorbidities, and serious psychological distress, PWE are more likely to report having 14 or more physical, mental, and general unhealthy days in the last 30 days. Discussion: PWE have significantly higher rates of serious psychological distress and poor health-related quality of life after controlling for demographics, comorbidities. These comorbid conditions need to be factored into any comprehensive treatment strategy for managing PWE to achieve optimum quality of life.
Energy and Numerical Weather Prediction

Since the study of energy transformations and the numerical integration of simplifiied equations are sometimes used as alternative approaches to the same physical problem, it is often desirable that the simplified equations conserve total energy under reversible adiabatic processes. Preferably, the equations should also conserve the sum of kinetic energy and available potential energy, and they should describe the tendency for static stability to increase as kinetic energy is released. It is found that if the equation of balance is used as a filtering approximation, all the terms in the vorticity equation which involve both the rotational and the divergent part of the wind field should be retained, while, if the geostrophic equation is used, all of these terms in the vorticity equation should be omitted, if the equations are to possess suitable energy invariants. An n-layer model with the appropriate energy invariants is developed. The two-layer model may be the simplest possible model with variable static stability. The model appears to be suitable for theoretical studies of the general circulation. DOI: 10.1111/j.2153-3490.1960.tb01323.x
Assessment of self-selection bias in a pediatric unilateral hearing loss study

Abstract Objective To examine the differences between participants and nonparticipants in a study of children with unilateral hearing loss that might contribute to selection bias. Study Design Case-control study. Setting Academic pediatric otolaryngology practice. Subjects and Methods Comparison of clinical and sociodemographic characteristics between the 81 participants and 78 nonparticipants with unilateral hearing loss in a case-control study. Results Compared with nonparticipants, the study participants were younger but were diagnosed at an older age. Participants were more likely to have been diagnosed through a primary care screen and have normal ear anatomy, and less likely to have an attributed etiology for their unilateral hearing loss or tried assistive hearing devices. No other significant demographic, socioeconomic, or clinical differences were identified. Conclusion Self-selection bias may jeopardize both internal and external validity of study results and should be evaluated whenever possible. Methods to minimize self-selection bias should be considered and implemented during the planning stages of clinical studies.
Presenilin-1 is expressed in neural progenitor cells in the hippocampus of adult mice.

The functions of the presenilin-1 (PS-1) protein remain largely unknown. In adult brain PS-1 is expressed principally in neurons. However during development PS-1 is expressed more widely including in embryonic neural progenitors. To determine if PS-1 is expressed in neural progenitors in adult hippocampus we used bromodeoxyuridine (BrdU) labeling combined with immunostaining for BrdU, PS-1 and markers of neuronal or glial differentiation. Most BrdU labeled cells also expressed PS-1 at a time when few BrdU labeled cells expressed the early neuronal markers β-III tubulin or TOAD-64 and none expressed mature neuronal (NeuN or calbindin) or astrocytic (GFAP) markers. Cells expressing PS-1 and the neural progenitor marker nestin were also found. Thus PS-1 is expressed in neural progenitor cells in adult hippocampus implying its possible role in neurogenesis in adult brain.
Minimizing the statistical error in capture cross-section measurements

Abstract Measurements of the neutron capture cross-section are performed by measurement of the capture rate of a sample placed in a neutron beam. The capture rate is measured by surrounding the sample with gamma-ray detectors. The capture rate is corrected for background and divided by the rate of neutrons incident on the sample in order to obtain the capture yield. The neutron capture cross-section can be obtained from the capture yield if additional information such as the total or scattering cross-section is known. An error analysis was performed on the measured capture cross-section. The error was minimized with respect to the experimental time split of the capture, background and incident neutron rates and also with respect to the sample thickness. These calculations are useful for the planning of an efficient capture cross-section experiment. The derived equations are compared to experimental data and show excellent agreement. This type of error analysis and minimization is also valid for other types of partial cross-section measurements such as fission and scattering which have similar expressions for the measured yield.
A system for analyzing automatic assembly and disassembly operations

A system for evaluating products in their design phase has been developed. It is integrated into a CAD/CAM environment to calculate cost for assembling and disassembling parts. In previous work, a generic assembly and disassembly model was developed to represent operations required for product manufacturing and demanufacturing. To be useful, the model requires a method for translating high-level instructions from product designers into low-level assembly and disassembly instructions. This paper presents a set of rules for accomplishing this task. The developed rules are used for manipulating strings representing parts and handlers in binary assembly and disassembly operations. A telephone assembly and disassembly simulation is used to illustrate the developed system.
Ventricular assist devices and artificial hearts: Mechanical solutions to the biological problem of congestive heart failure

S ubstantial improvements have been made over the past 15 years in the treatment of acute cardiac illnesses. Patients are often carried through 1 or more episodes using medical or surgical therapies. From 1980 to 1993, the death rate from acute myocardial infarction (MI) decreased by 30%.’ However, the natural history of ischemic heart disease is rclentlessly progressive despite palliative ellbrts. Consequently, a conversion occurs from acute episodic illness to chronic disease. The final common pathway of many chronic cardiac diseases leads to muscular left ventricular (Lv) failure, manifest primarily as congestive heart failure (CHF). As stated by Eugene Braunwald in his editorial, “Cardiovascular Care at the Turn of the Millennium,” CHF is “one of two emerging epidemics of cardiovascular disease.” Z
Post-placement rewiring and rebuffering by exhaustive search for functional symmetries

Separate optimizations of logic and layout have been thoroughly studied in the past and are well documented for common benchmarks. However, to be competitive, modern circuit optimizations must use physical and logic information simultaneously. In this work, we propose new algorithms for rewiring and rebuffering - a post-placement optimization that reconnects pins of a given netlist without changing the logic function and gate locations. These techniques are compatible with separate layout and logic optimizations, and appear independent of them. In particular, when the new optimization is applied before or after detailed placement, it approximately doubles the improvement in wirelength. Our contributions are based on exhaustive search for functional symmetries in sub-circuits consisting of several gates. Our graph-based symmetry finding is more comprehensive than previously known algorithms - it detects permutational and phase-shift symmetries on multiple input and output wires, as well as hybrid symmetries, creating more opportunities for rewiring and rebuffering.
Understanding the performance of concurrent error detecting superscalar microarchitectures

Superscalar out-of-order micro architectures can be modified to support redundant execution of a program as two concurrent threads for soft-error detection. However, the extra workload from redundant execution incurs a performance penalty due to increased contention for resources throughout the datapath. We present four key parameters that affect performance of these designs, namely 1) issue and functional unit bandwidth, 2) issue queue and reorder buffer capacity, 3) decode and retirement bandwidth, and 4) coupling between redundant threads' instantaneous resource requirements. We then survey existing work in concurrent error detecting superscalar micro architectures and evaluate these proposals with respect to the four factors
FULLY-EXPLICIT AND SELF-CONSISTENT ALGEBRAIC REYNOLDS STRESS MODELS

A fully-explicit, self-consistent algebraic expression for the Reynolds stress, which is the exact solution to the Reynolds stress transport equation in the `weak equilibrium'' limit for two-dimensional mean flows for all linear and some quasi-linear pressure-strain models, is derived. Current explicit algebraic Reynolds stress models derived by employing the `weak equilibrium'' assumption treat the production-to-dissipation (P varepsilon) ratio implicitly, resulting in an effective viscosity that can be singular away from the equilibrium limit. In the present paper, the set of simultaneous algebraic Reynolds stress equations are solved in the full non-linear form and the eddy viscosity is found to be non-singular. Preliminary tests indicate that the model performs adequately, even for three dimensional mean flow cases. Due to the explicit and non-singular nature of the effective viscosity, this model should mitigate many of the difficulties encountered in computing complex turbulent flows with the algebraic Reynolds stress models.
Integrating Online Compression to Accelerate Large-Scale Data Analytics Applications

Compute cycles in high performance systems are increasing at a much faster pace than both storage and wide-area bandwidths. To continue improving the performance of large-scale data analytics applications, compression has therefore become promising approach. In this context, this paper makes the following contributions. First, we develop a new compression methodology, which exploits the similarities between spatial and/or temporal neighbors in a popular climate simulation dataset and enables high compression ratios and low decompression costs. Second, we develop a framework that can be used to incorporate a variety of compression and decompression algorithms. This framework also supports a simple API to allow integration with an existing application or data processing middleware. Once a compression algorithm is implemented, this framework automatically mechanizes multi-threaded retrieval, multi-threaded data decompression, and the use of informed prefetching and caching. By integrating this framework with a data-intensive middleware, we have applied our compression methodology and framework to three applications over two datasets, including the Global Cloud-Resolving Model (GCRM) climate dataset. We obtained an average compression ratio of 51.68%, and up to 53.27% improvement in execution time of data analysis applications by amortizing I/O time by moving compressed data.
Rapid 3D cone-beam reconstruction with the Algebraic Reconstruction Technique (ART) by utilizing texture mapping graphics hardware

The Algebraic Reconstruction Technique (ART) reconstructs a 2D or 3D object from its projections. It has, in certain scenarios, many advantages over the more popular Filtered Backprojection approaches and has also recently been shown to perform well for 3D cone-beam reconstruction. However, so far ART's slow speed has prohibited its routine use in clinical applications. Here, the authors devise a new hardware acceleration scheme, employing readily available texture mapping graphics hardware, that allows quality 3D cone-beam reconstructions to be obtained at almost interactive speeds.
SO(10) and SU(6) unified theories on an elongated rectangle

Abstract Maximally supersymmetric SO ( 10 ) and SU ( 6 ) unified theories are constructed on the orbifold T 2 / ( Z 2 × Z 2 ′ ) , with one length scale R 5 taken much larger than the other, R 6 . The effective theory below 1 / R 6 is found to be the highly successful SU ( 5 ) theory in 5D with natural doublet–triplet splitting, no proton decay from operators of dimension four or five, unified mass relations for heavier generations only, and a precise prediction for gauge coupling unification. A more unified gauge symmetry, and the possibility of Higgs doublets being components of the higher-dimensional gauge multiplet, are therefore compatible with a large energy interval where physics is described by SU ( 5 ) gauge symmetry in 5D. This leads to the distinctive branching ratios for proton decay from SU ( 5 ) gauge boson exchange, p → l + π 0 , l + K 0 , ν ¯ π + , ν ¯ K + ( l = e , μ ), for well-motivated locations for matter. Several phenomenological features of the higher unified gauge symmetry are discussed, including the role of an extra U ( 1 ) gauge symmetry, which survives compactification, in the generation of neutrino masses.
Neutral and Charged Clusters in the Atmosphere: Their Importance and Potential Role in Heterogeneous Catalysis

Extensive investigations of the bonding of atmospherically important molecules to various ions have been made, and the results are used to clarify the overall gas-to-particle conversion process involving a single ionic species. Neutral and charged clusters play an important role in atmospheric processes, and an understanding of their states and reactivity is essential in developing a fundamental understanding and basis for assessing the importance of heterogeneous processes. The purpose of this paper is to survey briefly the current knowledge in these various fields and to recommend studies needed for further progress in quantifying aerosol formation and catalytic reactivity. The topics surveyed include clusters between ions and molecules and among neutral molecules, bonding and stability of small neutral-neutral complexes and related charge transfer complexes, and gas-to-particle conversion. 92 references, 5 figures, 2 tables.
Acoustooptic correlation processing in random noise radar

A new technique has been developed that permits coherent processing of backscatter data acquired by a radar system transmitting ultrawideband (UWB) random noise waveforms and processing the received signals using a heterodyne correlation receiver. This technique has been used in various applications, such as Doppler estimation, polarimetry, interferometry, buried-object detection, synthetic aperture radar (SAR) imaging, inverse SAR (ISAR) imaging, foliage penetration imaging, etc. One of the major advantages of the noise radar system is its inherent immunity to external interference. In such a radar system, the correlation receiver consists of a programmable variable-delay line, a mixer followed by a lowpass filter. One drawback of this type of receiver is that it sequentially processes the target returns, thus limiting the system response time and the dynamic detection range. We have recently integrated a novel heterodyning acoustooptic (AO) time-integrating correlation receiver that uses a traveling-wave AO deflector for wideband signal processing. The transmit waveform modulates the intensity of a laser diode that is multiplied by the traveling-wave modulation produced by the AO deflector, and the correlation is time-integrated on a charge-coupled device photodetector array. The principal advantages of this AO correlation receiver are its ability to generate a large range of variable delays, as well as to perform the signal correlation operation in parallel. Compared to the conventional sequential correlation receiver using a variable stepped delay line and correlator, implementation of the AO variable-delay line and heterodyning correlator can 1) reduce the processing time and greatly increase the processing gain due to the parallel correlation mechanism and 2) greatly increase the number of range cells depending on the number of resolvable spots of the AO deflector. This results in rapid data acquisition, longer integration time on parallel detector pixels (3000 pixels), and improved SNR. It is also shown that this radar has more range gates (up to 1000), which ultimately improves the detectable range resolution. Furthermore, several field experiments performed with different target arrangements demonstrate that the acoustooptic variable-delay line and correlator is able to profile various targets instantaneously and with very high SNR.
The role of endosymbiotic Wolbachia bacteria in the pathogenesis of river blindness

Parasitic filarial nematodes infect more than 200 million individuals worldwide, causing debilitating inflammatory diseases such as river blindness and lymphatic filariasis. Using a murine model for river blindness in which soluble extracts of filarial nematodes were injected into the corneal stroma, we demonstrated that the predominant inflammatory response in the cornea was due to species of endosymbiotic Wolbachia bacteria. In addition, the inflammatory response induced by these bacteria was dependent on expression of functional Toll-like receptor 4 (TLR4) on host cells.
Secondary and Conformational Specificities of Trypsin and Chymotrypsin

Specific and non-specific trypsin substrates of known structure have been examined for common features. This analysis suggests that trypsin has a specificity for a particular conformation near the scissile bond which I denote as a conformational specificity. This conformation is a bent left-handed helix at the third and fourth (P3 and P4) amino acid positions toward the amino terminus from the scissile bond which I denote as a conformational specificity. This conformation is a bent left-handed show a high frequency of proline and glycine at these positions consistent with the left-handed helical conformation. This apparent secondary specificity for a particular substrate residue other than that at the primary position is not related to the nature of the residues at the third and fourth positions. Rather, these residues determine the bend of left-handed helix which has the effect of exposing main chain hydrogen-bonding groups of the substrate peptide chain to hydrogen-bonding groups on the enzyme. Thus, the secondary specificity of trypsin is not sequence-specific, but is for peptide main chain in the third and fourth positions and is determined by the tertiary structure of the substrate. This hypothesis for conformational and secondary specificity in trypsin can be extended to chymotrypsin. It also provides a means for the regulation of certain processes in vivo catalyzed by other proteases.
Supporting collaborative help for individualized use

In this paper, we seek to advance the research around utilizing collaborative help for supporting individualized use of technologies. We do this by shedding light on the ways that users of MythTV, a highly flexible open-source software system for home entertainment enthusiasts, collaboratively help one another in maintaining their individualized MythTV systems. By analyzing the MythTV user community's mailing list archive, documentation, and wiki, coupled with user interviews we discuss how the community utilizes configuration artifacts as proxies to easily mobilize and exchange knowledge. While exchanging concrete artifacts such as scripts and configuration files was seen to sometimes increase the efficiency of knowledge transfer, it also presented several challenges. Negotiating the transparency of configuration artifacts, navigating the customization and appropriation gulfs, and aligning usage trajectories all emerged as problematic areas. We discuss design implications that address these challenges. Our findings provide a crucial understanding for how to support users in their individualized use of systems.
Incisionless in-office castration using a veterinary castration device (Burdizzo clamp)

Nonoperative ablation of the testicular artery has been described in animals using the Burdizzo clamp, but not in humans. We report a case of incisionless castration performed using local anesthesia, in a transsexual who wished to avoid the pain, expense, and scar associated with the open procedure. The Burdizzo clamp crushed the spermatic cord bilaterally, and the testis was allowed to atrophy. The soft-tissue damage was minimal, and the serum testosterone fell to castrate levels. This method has proved useful for castration in a transgender patient, but could also be used for castration in patients with advanced prostate cancer.
A Lot More to Do: The Sensitivity of Time-Series Cross-Section Analyses to Simple Alternative Specifications

In 1995, Beck and Katz (B&K) instructed the profession on “What to do (and not to do) with time-series, cross-section data,” and almost instantly their prescriptions became the new orthodoxy for practitioners. Our assessment of the intellectual aftermath of this paper, however, does not inspire confidence in the conclusions reached during the past decade. The 195 papers we reviewed show a widespread failure to diagnose and treat common problems of time-series, cross-section (TSCS) data analysis. To show the importance of the consequences of the B&K assumptions, we replicate eight papers in prominent journals and find that simple alternative specifications often lead to drastically different conclusions. Finally, we summarize many of the statistical issues relative to TSCS data and show that there is a lot more to do with TSCS data than many researchers have apparently assumed.
Forrester's Urban Dynamics: A Sociologist's Inductive Critique

The formal aspects of Forrester's general procedure and some of the substantive assumptions incorporated in his model are discussed. The evaluation is based on the methodological dictum that the status of a model's predictions should be assessed in terms of the assumptions that determine these outcomes. In order to identify the control structure of Forrester's model, the implications of variations in the following parameters or structural assumptions are studied: the basic transition rates in the sectors industry and housing; the multipliers that relate to the competition for scarce land; an alternative conception of industrial regeneration; the conditions governing pressures and flows in the population sector that induce an overall "converter" cycle; and the underemployed/labor job ratio and its concomitants. The latter two sets of conditions are reviewed in terms of their relationship to the general development of industry. The situation of the underemployed is analyzed and their existence set in relation to general features of the present stage of industrialization. The particular closed-system conceptualization that underlies the model is discussed, and an assessment of its adequacy to the problem is presented.
Development of a Pentavalent Rotavirus Vaccine against Prevalent Serotypes of Rotavirus Gastroenteritis

The strategy of decreasing the morbidity and mortality associated with rotavirus gastroenteritis through vaccination is supported by studies demonstrating that wild-type rotavirus infection protects against subsequent rotavirus disease. Primary infection with wild-type rotavirus typically induces homotypic immunity. Vaccination of infants with a multivalent vaccine directed against prevalent rotavirus serotypes is the strategy most likely to provide the broadest degree of protection against rotavirus gastroenteritis. The pentavalent human-bovine reassortant rotavirus vaccine (HBRV) is directed against each of the most prevalent rotavirus serotypes, including G1, G2, G3, G4, and P1. The safety, immunogenicity, and efficacy of different reassortant compositions and formulations of the HBRV have been evaluated in clinical trials. An HBRV dose of > or =8 x 10(6) plaque-forming units has demonstrated 68.8%-76.6% efficacy against any rotavirus gastroenteritis, regardless of severity, and approximatel 100% efficacy against severe rotavirus gastroenteritis for the first rotavirus infection season after vaccination. The HBRV has been generally well tolerated, with no increase in the incidence of fever, vomiting, diarrhea, or behavioral changes among vaccine recipients, compared with placebo recipients, during the 14- and 42-day periods after administration of any dose. Shedding of vaccine strains in feces is uncommon. A large-scale trial is under way to evaluate the efficacy and safety of the manufacturing-scale formulation of pentavalent HBRV.
Pulmonary artery hypertension in severe aortic stenosis: Incidence and mechanism

We investigated the incidence and mechanism of pulmonary artery hypertension (PAH) in a consecutive series of patients with aortic stenosis who were undergoing diagnostic cardiac catheterization. Forty-five patients with severe aortic stenosis were divided into two groups: group 1 comprised 13 patients (29%) with PAH (pulmonary artery systolic pressure > 50 mm Hg); group 2 comprised 32 patients (71%) without PAH. Group 1 patients had a higher incidence of congestive heart failure, a lower left ventricular ejection fraction and cardiac index, and more mitral regurgitation as compared with group 2 patients. Of the 13 group 1 patients, 8 had a transpulmonary gradient (pulmonary artery mean pressure--pulmonary capillary wedge pressure) > or = 10 mm Hg, consistent with reactive PAH. We conclude that PAH frequently accompanies aortic stenosis and is often reactive.
Identification and quantification of polyfunctionalized hopanoids by high temperature gas chromatography–mass spectrometry

Hopanoids are triterpenoids produced mainly by bacteria, are ubiquitous in the environment, and have many important applications as biological markers. A wide variety of related hopanoid structures exists, many of which are polyfunctionalized. These modifications render the hopanoids too involatile for conventional gas chromatography (GC) separation, so require either laborious oxidative cleavage of the functional groups or specialized high temperature (HT) columns. Here we describe the systematic evaluation and optimization of a HT–GC method for the analysis of polyfunctionalized hopanoids and their methylated homologs. Total lipid extracts are derivatized with acetic anhydride and no further treatment or workup is required. We show that acid or base hydrolysis to remove di- and triacylglycerides leads to degradation of several BHP structures. DB-XLB type columns can elute hopanoids up to bacteriohopanetetrol at 350 °C, with baseline separation of all 2-methyl/desmethyl homologs. DB-5HT type columns can additionally elute bacteriohopaneaminotriol and bacteriohopaneaminotetrol, but do not fully separate 2-methyl/desmethyl homologs. The method gave 2- to 7-fold higher recovery of hopanoids than oxidative cleavage and can provide accurate quantification of all analytes including 2-methyl hopanoids. By comparing data from mass spectra with those from a flame ionization detector, we show that the mass spectromet (MS) response factors for different hopanoids using either total ion counts or m/z 191 vary substantially. Similarly, 2-methyl ratios estimated from selected-ion data are lower than those from FID by 10–30% for most hopanoids, but higher by ca. 10% for bacteriohopanetetrol. Mass spectra for a broad suite of hopanoids, including 2-methyl homologs, from Rhodopseudomonas palustris are presented, together with the tentative assignment of several new hopanoid degradation products.
Cardiac Resynchronization Therapy and Automatic Implantable Cardiac Defibrillators in the Treatment of Heart Failure: A Review Article

Purpose To review the use of cardiac resynchronization therapy (CRT)and automatic implantable cardiac defibrillators (AICDs)in heart failure (HF)patients. Data Sources Selected scientific literature. Conclusions New developments in device therapy for HF patients are helping to decrease morbidity and mortality in this challenging patient population. CRT improves left ventricular (LV) ejection fraction, quality of life, 6-min walk distances, and New York Heart Association scores in select patients. AICDs can prevent sudden cardiac death in those who have LV dysfunction and are at risk for ventricular arrhythmias. Cardiac devices are now becoming a standard of care for those with HF who meet certain criteria. Implications for Practice Despite advances in medical therapy for treating LV dysfunction, newly diagnosed patients face a 50% mortality rate in 5 years. The natural history of HF leads to continual deterioration of function unless adverse cardiac remodeling is reversed. Until recently, the only means for improving symptoms and cardiac function has been through the optimization of standard medicines that are indicated for LV dysfunction, such as angiotensin-converting enzyme inhibitors and beta-blockers. However, not all patients benefit from medical management alone. Cardiac devices may now be considered when significant symptoms persist after standard medicines are optimized. When practitioners use a multiple-modality approach, careful patient selection based on the inclusion criteria used in the trials outlined in this article will likely lead to improved management of those with LV dysfunction.
Estrogens, Progestins, and Heart Disease Can Endothelial Function Divine the Benefit?

Coronary atherosclerosis is a prevalent, preventable, but slow disease. Demonstrating the clinical effect of an intervention requires at least 3 to 5 years, even in high-risk populations. Despite considerable supportive observational data, the value of hormone replacement therapy in the treatment of coronary heart disease in postmenopausal women remains uncertain.1 2 3 4 It is therefore very attractive to look for intermediate biological outcomes that may more quickly predict the results of event trials. One intermediate biological outcome, the anatomic progression of coronary atherosclerosis, has been shown to correlate with the incidence of cardiovascular events.5 Changes in angiographic disease progression, however, even with clinically successful interventions such as cholesterol lowering, do not occur in less than 1 to 2 years.6 The endothelium is thought to play an important role in the genesis of atherosclerosis, and changes in endothelial function have been reported within an hour of either estrogen administration or cholesterol lowering.7 8 9 If changes in endothelial function were found to predict the clinical benefit of interventions, then drug and lifestyle changes could be evaluated more rapidly. In this issue, Sorensen and coworkers10 report that cyclical estradiol and norethisterone hormone replacement therapy administered for 2.9±0.5 years did not improve endothelial function, measured as brachial artery flow–mediated vasodilation. The authors conclude that the addition of a progestin in a hormone replacement regimen may counteract the beneficial effects of estrogen alone on cardiovascular disease. If confirmed by other investigations, this study suggests that clinical trials of combined hormone replacement therapy will not find a beneficial effect on events and/or that endothelial function is not an appropriate intermediate biological outcome for assessing coronary heart disease therapy. Either finding would be an important observation. Although unproven, several lines of evidence suggest that the effect of an intervention on …
The Benefits of Harvesting Wetland Invaders for Cellulosic Biofuel: An Ecosystem Services Perspective

The emerging interest in cellulosic biofuel production has led the call for alternative cropping systems that maximize production along with the accompanying regulating, supporting, and cultural ecosystem services. We evaluate the potential for biomass harvested from invaded wetlands to achieve these goals. The ecosystem service trade-offs associated with a wetland invader harvest are evaluated followed by a case study estimating the energy production and nutrient removal of harvesting Phalaris arundinacea from invaded wetlands in Wisconsin, United States. Estimates for energy production from this single species harvest dwarf current renewable energy sources for the state of Wisconsin and offer the potential to recapture approximately 50‐200% of the excess nitrogen and phosphorus annually applied as fertilizer. This restoration technique would not only generate income from biomass sales to subsidize the cost of restoration, but also has the potential to shift the system toward more desirable environmental conditions by removing nutrients annually, reducing downstream eutrophication, and enhancing the ability of more desirable vegetation to establish by removing the litter layer created by the invasive species.
Darwin's Metaphors Revisited: Conceptual Metaphors, Conceptual Blends, and Idealized Cognitive Models in the Theory of Evolution

Darwin's book On the Origin of Species by Means of Natural Selection (henceforth The Origin) abounds with metaphors. In fact, the very theory of natural selection is couched in a system of metaphors that exhibit striking consistency and coherence. I argue that the phenomenon for which Darwin tries to detect the basic mechanisms, that is, biological evolution, involves vast, indeterminate, and ambiguous observations that are difficult to subject to the empirical methods. This fact motivates Darwin's extensive use of metaphors to organize his observations, structure the vague concepts, and ultimately render his observations meaningful and intelligible. I demonstrate that Darwin's metaphors, as far as they are elements of Idealized Cognitive Models, prove valuable in achieving this goal. First, I identify the conceptual metaphors underlying the main metaphorical expressions and show how these conceptual metaphors give rise to entailments and inferences central to Darwin's theory. The conceptual metaphors I i...
Borrelia burgdorferi OspC Protein Required Exclusively in a Crucial Early Stage of Mammalian Infection

This study demonstrates a strict temporal requirement for a virulence determinant of the Lyme disease spirochete Borrelia burgdorferi during a unique point in its natural infection cycle, which alternates between ticks and small mammals. OspC is a major surface protein produced by B. burgdorferi when infected ticks feed but whose synthesis decreases after transmission to a mammalian host. We have previously shown that spirochetes lacking OspC are competent to replicate in and migrate to the salivary glands of the tick vector but do not infect mice. Here we assessed the timing of the requirement for OspC by using an ospC mutant complemented with an unstable copy of the ospC gene and show that B. burgdorferi's requirement for OspC is specific to the mammal and limited to a critical early stage of mammalian infection. By using this unique system, we found that most bacterial reisolates from mice persistently infected with the initially complemented ospC mutant strain no longer carried the wild-type copy of ospC. Such spirochetes were acquired by feeding ticks and migrated to the tick salivary glands during subsequent feeding. Despite normal behavior in ticks, these ospC mutant spirochetes did not infect naive mice. ospC mutant spirochetes from persistently infected mice also failed to infect naive mice by tissue transplantation. We conclude that OspC is indispensable for establishing infection by B. burgdorferi in mammals but is not required at any other point of the mouse-tick infection cycle.
A Zinc(II) Photocage Based on a Decarboxylation Metal Ion Release Mechanism for Investigating Homeostasis and Biological Signaling

Metal ion signaling in biology has been studied extensively with ortho-nitrobenzyl photocages; however, the low quantum yields and other optical properties are not ideal for these applications. We describe the synthesis and characterization of NTAdeCage, the first member in a new class of Zn(2+) photocages that utilizes a light-driven decarboxylation reaction in the metal ion release mechanism. NTAdeCage binds Zn(2+) with sub-pM affinity using a modified nitrilotriacetate chelator and exhibits an almost 6 order of magnitude decrease in metal binding affinity upon uncaging. In contrast to other metal ion photocages, NTAdeCage and the corresponding Zn(2+) complex undergo efficient photolysis with quantum yields approaching 30 %. The ability of NTAdeCage to mediate the uptake of (65) Zn(2+) by Xenopus laevis oocytes expressing hZIP4 demonstrates the viability of this photocaging strategy to execute biological assays.
Severe Congenital Obstruction of the Left Main Coronary Artery Coexisting With Supravalvular Aortic Stenosis in Williams Syndrome: A Dangerous Association

Congenital obstruction of the left main coronary artery is a complicating feature of supravalvular aortic stenosis. We describe an eight-month-old female patient with Williams syndrome, supravalvular aortic stenosis, and branch pulmonary artery stenosis, with concomitant anomaly of severe obstruction of the left coronary artery orifice.