cssi/SciSciGPT-SciSciNet huggingface dataset:
HIV prescriptions on the frontlines: Primary care providers' use of antiretrovirals for prevention in the Southeast United States, 2017

Abstract HIV disproportionately affects persons in Southeast United States. Primary care providers (PCPs) are vital for HIV prevention. Data are limited about their prescribing of antiretrovirals (ARVs) for prevention, including non-occupational post-exposure prophylaxis (nPEP), pre-exposure prophylaxis (PrEP), and antiretroviral therapy (ART). We examined these practices to assess gaps. During April–August 2017, we conducted an online survey of PCPs in Atlanta, Baltimore, Baton Rouge, Miami, New Orleans, and Washington, DC to assess HIV-related knowledge, attitudes and practices. Adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) were used to estimate correlates of nPEP, PrEP and ART prescribing practices. Adjusting for MSA and specialty, the weighted sample (n = 820, 29.6% adjusted response rate) comprised 60.2% white and 59.4% females. PCPs reported ever prescribing nPEP (31.0%), PrEP (18.1%), and ART (27.2%). Prescribing nPEP was associated with nPEP familiarity (aPR = 2.63, 95% CI 1.59, 4.35) and prescribing PrEP (aPR = 3.57, 95% CI 2.78, 4.55). Prescribing PrEP was associated with PrEP familiarity (aPR = 4.35, 95% CI 2.63, 7.14), prescribing nPEP (aPR = 5.00, 95% CI 2.00, 12.50), and providing care for persons with HIV (aPR = 1.56, 95% CI 1.06, 2.27). Prescribing ART was associated with nPEP familiarity (aPR = 1.89, 95% CI 1.27, 2.78) and practicing in outpatient public practice versus hospital-based facilities (aPR = 2.14 95% CI 1.51, 3.04), and inversely associated with collaborations involving specialists (aPR = 0.60, 95% CI 0.42, 0.86). A minority of PCPs surveyed from the Southeast report ever prescribing ARVs for prevention. Future efforts should include enhancing HIV care coordination and developing strategies to increase use of biomedical tools.
Geography Taught as if It Matters

Nel Noddings (2013, 2015) argues there is no school subject more crucial than geography for making “better adults” who will serve as caring and responsible stewards of planet Earth. This perspective assigns geography a far greater role in school (and college) programs than in many places today. In this essay, I elaborate what such a perspective could mean. Specifically, I explore how relationships—both among humans and in subject matter—enable a geographic education that reaches young people. As touchstones for discussion, I draw on two propositions Noddings repeatedly advances: (1) geography considered as a study of the earth as the “home” of humans and other living things provides a sound basis for the selection of topics for study, and (2) children’s interests “employed wisely will lead to knowledge and attitudes that are adequate for personal fulfillment and for citizenship” (Noddings, 2012, p. 194).
Unfulfilled Expectations: One Economist’s History

The problem of expectations in economic models is reviewed through the intellectual development of the author. Initial efforts at macroeconomic modeling such as Foley–Sidrauski (Foley and Sidrauski 1971) treated expectations as conditioning variables for representative agent stock demands and supplies of financial and real assets. Perfect foresight (rational expectations) in this context leads to saddle-point instability of equilibrium, and the unanswered question of what behavioral forces will guarantee that the economy stays on the stable manifold. In later work such as Foley–Albin (Albin 1998), the economy appears as a complex, adaptive system far from equilibrium in which endogenous regime shifts make the statistical formation of expectations impossible. This perspective calls into question the presumed central role of expectations formation in structuring macroeconomic dynamics. The quantal response statistical equilibrium model can throw some light on the process by which markets penalize incorrect expectations of price change.
Social Media Sensationalism in the Male Infertility Space: A Mixed Methodology Analysis.

PURPOSE Infertile couples increasingly turn to the internet for medical guidance. The aims of this study were: (1) to identify popular male infertility content on social media, and (2) to assess the accuracy and quality of this content. We hypothesized that inaccurate/misleading information proliferates online. MATERIALS AND METHODS We used the analytics module BuzzSumo to identify article links that were most shared on Facebook, Pinterest, Reddit, and Twitter related to male infertility during September 2018 to August 2019. We excluded articles with <100 engagements, defined as "likes," "comments," and "shares." Two researchers graded content as accurate, misleading, or inaccurate by comparing content to references cited and contemporary research. Inter-rater reliability was determined with Cohen's κ. Binary logistic regression was performed to compare user engagement with accurate versus inaccurate/misleading articles. RESULTS Fifty-two unique article links were identified, with 421,004 total engagements. Thirty-four articles referenced 15 scientific studies; no reference was available for 18 links. Fifty-six percent of articles were accurate and 44% misleading/inaccurate (κ=0.743). No significant difference was found in total engagement between accurate vs. misleading/inaccurate links (p=0.805). Twenty-four percent of engagements referenced studies using non-human models, and 26% of studies had sample sizes <100. CONCLUSIONS Social media platforms foster engagement with male infertility information. However, sensationalism predominates, as patients are highly likely to encounter misleading/inaccurate information, articles that overstate implications of animal research, and conclusions made based on limited sample sizes. Urologists should consider adding social media to their armamentarium to stave off misinformation and engage proactively with patients.
Thinking outside the lumen: fractional flow reserve versus intravascular imaging for major adverse cardiac event prediction.

If you always do what you always did, you will always get what you always got —Albert Einstein [(1)][1] Four decades ago, we believed in a dogma that acute myocardial infarction (MI) resulted from near total luminal obstruction by progressive thickening of coronary atheroma. At that time,
The changing epidemiology of dog bite injuries in the United States, 2005-2018.

In 2018, the most recent year for which data are available, dog bites ranked as the 13th leading cause of nonfatal emergency department visits in the United States. As dog ownership spirals upwards in the United States, it is important to continue to monitor the epidemiology of dog bite injuries. This study provides contemporary data on the incidence of dog bites injuries in the United States and in New York and profiles individuals who have been treated for dog bites in emergency departments. The study also examines the demographic correlates of the rate of injuries at the neighborhood level in New York City and maps the rate in each neighborhood. At the national level, the study examines longitudinal data on dog bite injuries from 2005 to 2018 gathered by the Centers for Disease Control and Prevention. For New York, the study analyzes data for 2005–2018 collected by the New York State Department of Health. A negative binomial regression analysis was performed on the state data to measure the simultaneous effects of demographic variables on the incidence of dog-related injuries. A thematically shaded map of the rate of dog bite injuries in New York City’s neighborhoods was created to identify neighborhoods with higher-than-average concentration of injuries. In both the United States and New York the rate of dog-bite injuries increased from 2005 to 2011 and then underwent a significant decline. Injuries due to dog bites, however, still remain a sizable public health problem. Injuries are more prevalent among school-age children, inhabitants of less-densely populated areas, and residents of poorer neighborhoods. In New York City, poorer neighborhoods are also associated with fewer dogs being spayed or neutered. To reduce the rate of dog bite injuries, prevention programs – particularly those which center on teaching the dangers of canine interactions with humans – should be targeted at children. Dog bite injuries tend to be clustered in identifiable neighborhoods. Dog bite prevention programs and stricter enforcement of dog laws can target these neighborhoods.
Integrating Learning Interpersonal Skills through Team-Based Learning (TBL) in a Management Course.

Our study explores the effectiveness of Team-Based Learning (TBL) using an online film analysis project in a management course. TBL is designed to foster student learning and develop interpersonal ...
Rebooting atrial fibrillation ablation in the COVID-19 pandemic.

Catheter ablation procedures for atrial fibrillation (AF) were significantly curtailed during the peak of coronavirus disease 2019 (COVID-19) pandemic to conserve healthcare resources and limit exposure. There is little data regarding peri-procedural outcomes of medical procedures during the COVID-19 pandemic. We enacted protocols to safely reboot AF ablation while limiting healthcare resource utilization. We aimed to evaluate acute and subacute outcomes of protocols instituted for reboot of AF ablation during the COVID-19 pandemic. Perioperative healthcare utilization and acute procedural outcomes were analyzed for consecutive patients undergoing AF ablation under COVID-19 protocols (2020 cohort; n=111) and compared to those of patients who underwent AF ablation during the same time period in 2019 (2019 cohort; n=200). Newly implemented practices included preoperative COVID-19 testing, selective transesophageal echocardiography (TEE), utilization of venous closure, and same-day discharge when clinically appropriate. Pre-ablation COVID-19 testing was positive in 1 of 111 patients. There were 0 cases ablation-related COVID-19 transmission and 0 major complications in either cohort. Pre-procedure TEE was performed in significantly fewer 2020 cohort patients compared to the 2019 cohort patients (68.4% vs. 97.5%, p <0.001, respectively) despite greater prevalence of persistent arrhythmia in the 2020 cohort. Same-day discharge was achieved in 68% of patients in the 2020 cohort, compared to 0% of patients in the 2019 cohort. Our findings demonstrate the feasibility of safe resumption of complex electrophysiology procedures during the COVID-19 pandemic, reducing healthcare utilization and maintaining quality of care. Protocols instituted may be generalizable to other types of procedures and settings.
High-Content Clonogenic Survival Screen to Identify Chemoradiation Sensitizers.

Abstract Purpose The combination of cytotoxic chemotherapy with radiation therapy (CRT) has resulted in significant improvements in clinical outcomes for patients with many locally advanced unresectable cancers. Only a small proportion of patients achieve pathologic complete responses to CRT; combination of CRT with targeted agents offers the promise of further improving treatment responses. However, numerous clinical trials have failed to show an improvement in clinical outcomes with the addition of targeted agents. To increase the accessibility of our screening method and accelerate the pace at which novel combinations with CRT are identified and incorporated into standard practices for treatments, we report details on screening method optimization, data generation, and downstream data analysis. Methods In part, the gap in translation to large, expensive, and ultimately unsuccessful clinical trials reflects the shortcomings of inconsistently designed, executed, and reported preclinical data on which these studies are based. In an effort to standardize the selection of agents for future clinical testing, we have designed, optimized and validated a high throughput, high content, clonogenic assay platform for step-wise progression of preclinical studies from in vitro to in vivo in non-small cell lung cancer and pancreatic ductal adenocarcinoma. Results This highly stable in vitro method was standardized for identification of the most promising CTEP drugs that could best be combined with CRT from among as screen of multiple agents tested in an unbiased manner using 96-well plates. The methodology lends itself to seamless testing of multiple agents in a similar fashion allowing cross-comparisons, evaluation of CRT, or radiation therapy alone, and testing multiple concentrations of test agents sequenced at different times before and after radiation. The method identified Trametinib as a strong CRT sensitizer in KRAS-mutant non-small cell lung cancer and pancreatic ductal adenocarcinoma cell lines. This platform has enabled the screening and identification of several chemoradiation sensitizers.Conclusions: High throughput, high content clonogenic drug screening assay allows for the rapid identification of targets and agents to be translated to the clinic to help improve the effectiveness of current standard of care CRT in various solid tumors.
A Method for Improving the Dynamic Range of Integrated Diffuse Speckle Contrast Spectroscopy

We present a method to improve the dynamic range of blood flow measurements with Integrated Diffuse Speckle Contrast Spectroscopy (iDSCS) by reducing the detrimental effects of speckle averaging.
Optimal renormalization of multiscale systems

While model order reduction is a promising approach in dealing with multiscale time-dependent systems that are too large or too expensive to simulate for long times, the resulting reduced order models can suffer from instabilities. We have recently developed a time-dependent renormalization approach to stabilize such reduced models. In the current work, we extend this framework by introducing a parameter that controls the time decay of the memory of such models and optimally select this parameter based on limited fully resolved simulations. First, we demonstrate our framework on the inviscid Burgers equation whose solution develops a finite-time singularity. Our renormalized reduced order models are stable and accurate for long times while using for their calibration only data from a full order simulation before the occurrence of the singularity. Furthermore, we apply this framework to the three-dimensional (3D) Euler equations of incompressible fluid flow, where the problem of finite-time singularity formation is still open and where brute force simulation is only feasible for short times. Our approach allows us to obtain a perturbatively renormalizable model which is stable for long times and includes all the complex effects present in the 3D Euler dynamics. We find that, in each application, the renormalization coefficients display algebraic decay with increasing resolution and that the parameter which controls the time decay of the memory is problem-dependent.
Measurement of Dielectric Properties

General principles for measuring dielectric properties are discussed, and techniques and instruments used for measurements on agricultural materials are briefly presented. The measurement techniques appropriate for any particular application depend on the frequency of interest; the nature of the dielectric material to be measured, both physical and electrical; and the degree of accuracy required. Many different kinds of instruments can be used for measurement, but any instrument that provides reliable determinations of the required electrical parameters involving the unknown material in the frequency range of interest can be considered. Equipment and techniques are described for measurements ranging from audio frequencies up through the radio frequencies and into the microwave region.
Bootstrap Simulation, Markov Decision Process Models, and Role of Discounting in the Valuation of Ecological Criteria in Uneven-Aged Forest Management

This chapter presents general methods combining stochastic simulation and Markov decision process models, with a specific application to the issue of discounting ecological criteria. The literature argues for and against discounting ecological costs and benefits like standard financial investments. As part of this debate, this chapter investigates some purely ecological consequences of discounting ecological criteria. The methods are Markov decision process models with infinite time horizon and discounted or undiscounted ecological objectives, based on bootstrap simulations of stand growth. The data were from Douglas-fir/western hemlock forests in the U.S. Pacific Northwest, with the assumption of continuous-cover forestry. The ecological criteria examined here included the stand basal area per hectare, the tree species and size diversity measured with Shannon’s index, and the percentage of the forest in late seral stage. In maximizing expected tree species diversity, 18 out of 64 possible stand states would call for different decisions with discounting. For tree size diversity, the decisions differed for five stand states. For basal area all but two states called for the same decision. For late seral forest frequency, discounting led to different decisions for 13 stand states. However, for only a few stand states were the ecological criteria substantially different immediately after harvest. Thus, discounting would matter only for a few stand states, which in the study area had a low frequency. Given this initial condition, only the expected late seral forest frequency differed substantially after a decade with discounting. In the long run, the initial condition does not matter and discounting the criteria gave very similar values as not discounting.
Probe Calibration in Transient Microdialysis In Vivo

Purpose. We examine the theoretical basis for calibrating microdialysis probes in vivo for pharmacokinetic experiments in which the extracellular analyte concentrations vary in time.
Time-Distance Inversion Methods and Results - (Invited Review)

The current interpretations of the travel-time measurements in quiet and active regions on the Sun are discussed. These interpretations are based on various approximations to the 3-D wave equation such as the Fermat principle for acoustic rays and the Born approximation. The ray approximation and its modifications have provided the first view of the 3-D structures and flows in the solar interior. However, more accurate and computationally efficient approximations describing the relation between the wave travel times and the internal properties are required to study the structures and flows in detail. Inversion of the large three-dimensional datasets is efficiently carried out by regularized iterative methods. Some results of time-distance inversions for emerging active regions, sunspots, meridional flows and supergranulation are presented. An active region which emerged on the solar disk in January 1998, was studied from SOHO/MDI for eight days, both before and after its emergence at the surface. The results show a complicated structure of the emerging region in the interior, and suggest that the emerging flux ropes travel very quickly through the depth range of our observations. The estimated speed of emergence is about 1.3 km s-1. Tomographic images of a large sunspot reveal sunspot ‘fingers’ — long narrow structures at a depth of about 4 Mm, which connect the sunspot with surrounding pores of the same polarity.
PARAMETRIC INVESTIGATIONS OF VIBRATING CABLE NETWORKS

Natural frequencies and modes of vibration are determined for hyperbolic paraboloid cable networks composed of a linkage of straight members connected by frictionless pins with concentrated masses lumped at the connection points. The frequencies and mode shapes are determined through a QL transformation procedure using the linear equations of motion. A numerical problem is examined and the natural feequencies are presented. Six parameter studies are conducted to determine how the natural frequencies and mode shapes are altered in response to variations in scale factor, mass, applied force, modulus of elasticity, prestress, and sag.
Remarks On the Role of Quantity, Quality, and Relations in the History of Logic, Methodology and Philosophy of Science

Publisher Summary The analytic historian observed that one of the two major foundation crises in Greek mathematics arose from the collapse of an older theory of proportion. Euclid stated two definitions of an odd number: (1) an odd number is one that is not divisible by 2 and (2) an odd number is one that exceeds some even number by 1. A comparatively neglected problem in the history of mathematical thought is the set of later Platonic theories of Ideal Number. These numbers are said to be generated by the “one” and the “indeterminate dyad,” and have puzzling properties, such as “inaddibility.” The aim of mathematical physics is the exploitation of abstract mathematical objects for the description of the results of physical measurements. The success of this scheme depends upon the correct interpretation of the physical results and their proper identification with the appropriate mathematical objects. If these identifications are correct, the observable relationships among the physical objects are predictable by the algebraic properties of the corresponding mathematical objects.
Pycnophylactic interpolation revisited: integration with the dasymetric-mapping method

Dasymetric-mapping and pycnophylactic-interpolation methods have solid theoretical foundations and empirical supports in population-estimation research. Each of the methods has its own strengths, but also suffers obvious shortcomings. Dasymetric mapping makes good use of ancillary information to infer most likely population distribution, whereas it suffers from the unfounded assumption of uniform distribution of population among all eligible locations. Pycnophylactic interpolation warrants a smooth population surface in the study area without any presumption of uniform distribution. However, the method does not draw on information about real population distribution, so that its estimation accuracy cannot benefit from such useful information. In this paper, we develop a hybrid approach that takes advantage of the strengths and remedies the flaws of both methods. The hybrid method is tested with a case study. To evaluate the performance of the proposed hybrid method, this study compares its estimation accuracy with those of other popular methods including areal-weighting interpolation, binary dasymetric mapping and the pycnophylactic-interpolation method. The comparison results prove that the proposed hybrid method significantly outperforms the other methods. In addition, the study conducts a sensitivity analysis to examine the effect of search-radius size, which is the key parameter of the hybrid method, on estimation accuracy. The analysis result shows that the hybrid method can be further improved with appropriate choice of search radius.
A significant temporal and quantitative relationship exists between high-density lipoprotein levels and acute ischemic stroke presentation.

Abstract Background Reduced serum high-density lipoprotein (HDL-C) is an independent risk factor for ischemic stroke in elderly men. The temporal and quantitative relationships between HDL-C and acute ischemic stroke have not been defined. Methods We identified patients with first ever acute ischemic stroke presenting to our hospital between 2003 and 2006. Patients with serum fasting lipid levels drawn within 24 h of admission and at least one follow-up visit with a neurologist in our hospital were included. Clinical and laboratory data before, immediately after, and several weeks after the index stroke were collected. Results 191 patients were included (47% women, mean age 62 years). The mean time interval between pre-stroke lipid data and index stroke was 5.2 months; 50% of these patients were taking a statin medication. The mean time interval between index stroke and follow-up lipid testing was 2.6 months. Immediately after the index stroke, HDL-C levels decreased by 18% ( p p Conclusions HDL-C levels decrease significantly at the time of acute ischemic stroke. Prior history of myocardial infarction diminishes HDL-C depression at the time of stroke. HDL-C may be an acute phase reactant or nascent biomarker of acute stroke susceptibility. Further prospective studies are needed.
Mechanism of β-Hydrogen Abstraction from Adsorbed Alkoxides on Supported Metal Oxide Catalysts

The transition state and the mechanism of β-hydrogen abstraction from alkoxides adsorbed on vanadia monolayers supported on both ceria and anatase titania were investigated using a combination of temperature-programmed desorption (TPD) and microcalorimetry. The TPD studies demonstrated that the peak temperature for β-hydrogen abstraction from adsorbed ethoxides to produce acetaldehyde increased as the methyl group in the ethoxide was fluorinated. The calorimetry results showed that methyl group fluorination did not affect the heat of dissociative adsorption of the ethanol reactant. These observations are consistent with a transition state in which there is a positive charge on the β-carbon in the ethoxide and indicates that the reaction proceeds via hydride transfer to a vanadium site.
Tea forest in the making: Tea production and the ambiguity of modernity on China’s southwest frontier

Abstract The simultaneous but incompatible desires for both “tradition” and “advancement” have produced the “ambiguity of modernity” in the areas of minority nationalities ( shaoshu minzu diqu ) on China’s southwest frontier. This paper, in accordance, directly addresses the ambiguity of modernity through the investigation of the tea landscape in Yunnan. This essay builds on Aihwa Ong and Stephen Collier’s “global assemblage” framework to analyze the relationship between the “global form” of modernity and the situated assemblages of “ambiguity of modernity” in southwest China. Data are based on ethnographic research in the village of Mangjing, located in Jingmai Mountain, a renowned tea mountain in Yunnan. Most of the villagers in Mangjing are one of the minority nationalities of China, Bulang. I discuss the state-led project in transforming the modern tea plantation for “restoring” a landscape deemed as “ancient tea forest” ( guchalin ) in Mangjing. In addition, I address Bulang villagers’ and government officials’ multiple responses to the transformation of tea landscapes. I argue that the transformation of tea landscapes has been the practice to turn the “global form” of modernity into the shifting “assemblages” amongst tradition, modernity, science, and nature. The ambiguity of modernity has emerged from the shifting assemblages, providing both the state and Bulang villagers more leeway to symbolically and physically (re)produce meanings for the tea landscapes to meet the contingent market demand for tea. The transformation of tea landscapes, however, has become another process to perpetuate Bulang villagers’ social status of being “low quality” as China’s minority nationalities.
Exact Occupation Statistics for One-Dimensional Arrays of Dumbbells

Exact relationships are developed which describe the occupation statistics for one‐dimensional arrays of dumbbells. It is shown that in the limit, as the number of compartments per array tends to infinity, these relationships reduce to those calculated, using the Bethe approximation when the number of nearest neighbors is two. A partition function, which includes the influence of the configurational correlation inherent in a one‐dimensional array of dumbbells, is also derived and discussed.
Limits of hardness at the nanoscale: Molecular dynamics simulations

Contrary to the often reported findings from molecular dynamics computer simulation that metals soften as their grain sizes fall below 10--15 nm, we do not observe such softening in nanocrystalline specimens when they are first thermally relaxed. We offer a simple model that illustrates that the increased hardening is a consequence of grain-boundary relaxation, which suppresses grain-boundary sliding and forces the material to deform by dislocation glide. These observations provide an explanation for why some experiments observe an inverse Hall-Petch relationship at grain sizes below 10--20 nm while others do not.
Mechanism of resistance to ricin toxin in selected mouse lymphoma cell lines

The role of impaired toxin uptake in conferring cellular resistance to the plant toxin RCAII (ricin) has been examined using a murine BW5 147 lymphoma line and a toxin-resistant variant (BW5 147 RicR.3) selected by repeated exposure to RCAII. The toxin-resistant variant is 250 times more resistant to RCAII in long-term growth experiments and 1,000 times more resistant in short-term protein synthesis assays. Experiments with ferritin-conjugated 125I-labeled RCAII (ferritin-125I-RCAII) indicated that toxin binding to sensitive and resistant cells is similar at low toxin concentrations where maximum differential cytotoxicity occurs but that major difference exist with respect to toxin uptake. In sensitive cells toxin is internalized via endocytosis, and as seen previously in other systems subsequent rupture of some of the toxin-containing endocytotic vesicles releases toxin into the cytoplasm, where it inhibits protein synthesis. The process of toxin transfer to the cytoplasm is presumed to account for the one-hour lag before toxin-induced inhibition of protein synthesis can be detected. Endocytotic uptake of toxin is impaired in resistant BW5147RicR.3 cells, and they are unaffected by toxin concentrations that inhibit protein synthesis and kill sensitive parental cells. Killing of resistant cells at low toxin concentrations was accomplished by encapsulating RCAII into lipid vesicles capable of fusing with the plasma membrane. Direct introduction of toxin into resistant cells using lipid vesicles as carriers produced rapid inhibition (< 15 min) of protein synthesis and eliminated the lag in toxin action seen in sensitive cells exposed to free toxin. These findings are discussed in relation to the mechanism of toxin action and proposals that toxin activity requires structural modification of the toxin molecule at the cell surface before transport into the cell.
Kaposi's sarcoma in renal allograft recipients

The development of Kaposi's sarcoma in immunosuppressed patients is a rare occurrence, but poses a real threat to the patient due to the rapid progression of the unchecked disease. The suspicion of this disease will prompt early diagnosis by scrutiny of histologic preparations and prompt interruption of antirejection therapy. Four of five patients in whom a diagnosis was made preterminally responded favorably to withdrawal of immunosuppressive agents. In renal allograft recipients with mucocutaneous vascular lesions, Kaposi's sarcoma should be considered as a cause of gastrointestinal bleeding.
On shortest single/multiple path computation problems in Fiber-Wireless (FiWi) access networks

Fiber-Wireless (FiWi) networks have received con- siderable attention in the research community in the last few years as they offer an attractive way of integrating optical and wireless technology. As in every other type of networks, routing plays a major role in FiWi networks. Accordingly, a number of routing algorithms for FiWi networks have been proposed. Most of the routing algorithms attempt to find the "shortest path" from the source to the destination. A recent paper proposed a novel path length metric, where the contribution of a link towards path length computation depends not only on that link but also every other link that constitutes the path from the source to the destination. In this paper we address the problem of computing the shortest path using this path length metric. Moreover, we consider a variation of the metric and also provide an algorithm to compute the shortest path using this variation. As multipath routing provides a number of advantages over single path routing, we consider disjoint path routing with the new path length metric. We show that while the single path computation problem can be solved in polynomial time in both the cases, the disjoint path computation problem is NP-complete. We provide optimal solution for the NP-complete problem using integer linear programming and also provide two approximation algorithms with a performance bound of 4 and 2 respectively. The experimental evaluation of the approximation algorithms produced a near optimal solution in a fraction of a second.
In vitro chromosome damage due to PCB interactions

In order to study the possible mutagenic properties of polychlorinated biphenyls (PCBs), human lymphocyte cultures were examined for chromosome breakage, rearrangements, sister-chromatid exchange, and mitotic delay. The present study, which used cyclophosphamide as a positive control, shows that one planar PCB congener, 3,4,3',4'-tetrachlorobiphenyl, caused dose-related chromosome breakage in human lymphocytes exposed in vitro to 0.1-10(-4) micrograms/ml. In contrast, the non-planar PCB, 2,5,2',5', did not cause chromosome damage in comparable tests even at concentrations as high as 1 microgram/ml. However, when 3,4,3',4' at a concentration lower than that which causes chromosome breakage (10(-5) micrograms/ml) was combined with a non-clastogenic concentration of 2,5,2',5', the chromosomal damage observed was far in excess of what one would expect from higher doses of 3,4,3',4' alone. These results suggest that some PCB congeners may interact to cause synergistic genotoxic effects.
HABITAT PREFERENCES OF SURFACE-DIVING WATERBIRDS AND AMERICAN WHITE PELICANS WINTERING IN REDFISH BAY, TEXAS

Abstract Habitat preferences were determined for a guild of surface-diving waterbirds wintering in Redfish Bay, Texas: common loon (Gavia immer), eared grebe (Podiceps nigricollis), pied-billed grebe (Podilymbus podiceps), double-crested cormorant (Phalacrocorax auritus), red-breasted merganser (Mergus serrator), and American coot (Fulica americana). American white pelican (Pelecanus erythrorhynchos) also was included because it occupies habitats similar to those of the surface divers. Between November 2001 and April 2002, the locations of 4,232 surface divers and American white pelicans using aquatic habitats in Redfish Bay were recorded and entered into a GIS that included a National Wetlands Inventory layer. Bird habitat preferences-avoidances were determined using a test based on Bonferroni's inequality. American coots, American white pelicans, and pied-billed grebes preferred shallower estuarine subtidal seagrass beds, whereas common loons, double-crested cormorants, and eared grebes preferred deeper...
Enhanced Capture of Magnetic Microbeads Using Combination of Reduced Magnetic Field Strength and Sequentially Switched Electroosmotic Flow—A Numerical Study

Magnetophoretic immunoassay is a widely used technique in lab-on-chip systems for detection and isolation of target cells, pathogens, and biomolecules. In this method, target pathogens (antigens) bind to specific antibodies coated on magnetic microbeads (mMBs) which are then separated using an external magnetic field for further analysis. Better capture of mMB is important for improving the sensitivity and performance of magnetophoretic assay. The objective of this study was to develop a numerical model of magnetophoretic separation in electroosmotic flow (EOF) using magnetic field generated by a miniaturized magnet and to evaluate the capture efficiency (CE) of the mMBs. A finite-volume solver was used to compute the trajectory of mMBs under the coupled effects of EOF and external magnetic field. The effect of steady and time varying (switching) electric fields (150-450 V/cm) on the CE was studied under reduced magnetic field strength. During switching, the electric potential at the inlet and outlet of the microchannel was reversed or switched, causing reversal in flow direction. The CE was a function of the momentum of the mMB in EOF and the applied magnetic field strength. By switching the electric field, CE increased from 75% (for steady electric field) to 95% for lower electric fields (150-200 V/cm) and from 35% to 47.5% for higher electric fields (400-450 V/cm). The CE was lower at higher EOF electric fields because the momentum of the mMB overcame the external magnetic force. Switching allowed improved CE due to the reversal and decrease in EOF velocity and increase in mMB residence time under the reduced magnetic field strength. These improvements in CE, particularly at higher electric fields, made sequential switching of EOF an efficient separation technique of mMBs for use in high throughput magnetophoretic immunoassay devices. The reduced size of the magnet, along with the efficient mMB separation technique of switching can lead to the development of portable device for detection of target cells, pathogens, and biomolecules.
Individuals in an osprey colony discriminate between high and low quality information

A potential benefit of living in a colony is that animals may gain information about the location of good foraging sites from other colony members1–3. The role of information transfer as a major benefit favouring the evolution of coloniality is, however, very poorly understood4. Information transfer has been demonstrated for only a few colonial vertebrate species5–7, but not all colonial species share information8–10. Here I report that colonial ospreys (Pandion haliaetus, L.) not only transfer information about foraging locations, but that they discriminate among fish species brought back by other colony members, and respond only to schooling prey species. This information significantly reduces the search times needed for informed birds to capture patchily-distributed prey species. This is the first demonstration of a colonial vertebrate discriminating between prey species with different spatial distributions brought back by returning foragers, and selectively using information about location of prey species to increase foraging efficiency.
Selectivity of optical stimulation in the auditory system

It is known that electrical current injected from cochlear implant contacts spreads within the cochlea, causing overlapping stimulation fields and possibly limiting the performance of cochlear implant users. We have investigated an alternative mechanism to stimulate auditory neurons in the gerbil cochlea using a laser, rather than electrical current. With the laser, it is possible to direct the light to a selected, known volume of tissue that is smaller than the electrically stimulated population of cells. In the present experiments, a transiently expressed transcription factor, c-FOS, was used to stain activated nerve cells. Immunohistochemical staining for c-FOS in the cochlea shows a small area of optical stimulation, which occurs directly opposite to the optical fiber. Additionally, masking data indicate that the laser can stimulate a small population of cells similar to an acoustic toneburst. Smaller populations of stimulated cells could reduce the amount of overlap in stimulation fields and allow more stimulation contacts in a neuroprothesis.
Psychoneuroimmunology of autoimmune disorders

The interactions between the immune system and psychological states are both intricate and intriguing. Research at a molecular level has thrown considerable light on the previously ill-defined area of psychoneuroimmunology. In this report, we explore the psychoneuroimmunology of autoimmune disorders, particularly rheumatoid arthritis and lupus erythematosus. Animal models of these diseases have provided a particularly useful window on complex psychoneuroimmunological interactions. Observations about the effect of stress on the onset and course of autoimmune disorders has added to our understanding of psychoneuroimmunological interactions. These interactions are bi-directional, as reflected in the autoimmune-mediated neuropsychiatric manifestations of systemic lupus. Exploring the role of various neurotransmitters and neuromodulators in the stress response may have important therapeutic implications for autoimmune disorders.
Short distance coefficients and the vanishing of the lepton asymmetry in B → Vl + l −

We derive a condition the short distance coefficients governing $\stackrel{\ensuremath{\rightarrow}}{b}(s,d){\mathcal{l}}^{+}{\mathcal{l}}^{\ensuremath{-}}$ transitions must satisfy in order for the forward-backward asymmetry to vanish in the exclusive modes $\stackrel{\ensuremath{\rightarrow}}{B}{(K}^{*},\ensuremath{\rho}){\mathcal{l}}^{+}{\mathcal{l}}^{\ensuremath{-}}.$ This relation, which is satisfied in the standard model, involves the coefficient entering in $\stackrel{\ensuremath{\rightarrow}}{b}s\ensuremath{\gamma}$ transitions as well as one of the additional Wilson coefficients present in the leptonic modes. We show that the resulting relation is largely free of hadronic uncertainties, thus constituting a reliable test of the standard model in exclusive rare $B$ decays.
Fluid pressure and its effects on chemical mechanical polishing

Abstract The experimental results of interfacial fluid pressure and friction measurements during polishing are presented, as well as their dependence on some major process variables. Under simulated conditions, a sub-ambient fluid pressure was observed, and its magnitude was of the same order of magnitude as the applied polishing load. Since this fluid pressure is non-uniformly distributed, the contact stress, obtained by combining the effects of both applied load and the fluid pressure, is not uniform across the wafer and will result in non-uniform material removal. The mechanism of the presence of the fluid pressure was investigated, and an analytical model was developed to predict the magnitude and distribution of this fluid pressure. The effects of the sub-ambient fluid pressure on material removal rate and profile were tested with thermally grown silicon dioxide on 100 mm diameter, p-type (1 0 0), single-crystal silicon wafers. The polishing experiments show the effect of sub-ambient fluid pressure on polishing rate and profile.
An inventory model for delayed customization: A hybrid approach

We present a variant of the delayed customization problem in which the company considers using both regular production and postponement. We determine the optimal inventory levels for the generic product (to be used for postponement) and the regular products. Even when the use of the generic product is significantly more expensive than other products, maintaining an inventory of the generic product significantly increases profits. We present an algorithm to optimally solve the single period and heuristically solve the infinite horizon problems for any number of products, and present computational results.
Mechanisms of pollutant transport in the Hudson estuary

Abstract The discharge of industrial wastes and surface runoff of pollutant-laden soils have been occurring in the Hudson estuary since the 1890s. With tighter pollution control legislation eliminating most of the problem sources of pollution, the sediments of the Hudson River have now become the main source of pollutants in the estuary. Understanding the movement of sediments within the system is necessary in order to be able to determine the mechanisms of pollutant transport. This article presents some mechanisms describing how the majority of these sediments are moved from place to place and accumulated. Historical pollutant loadings in the estuary are presented in order to stress the magnitude of the problem. Studies on other estuaries are used as examples where no significant research has been conducted on the Hudson estuary.
The need for a national science policy

Technological development has produced for America the highest standard of living in history, but technology depends, in turn, on research. Thus, if our tremendous rate of production is to be continued, a national science policy must be formulated which will foster and maintain those conditions under which research can best be carried on.
Talking about Rates Conceptually, Part I: A Teacher's Struggle.

matics education. For reform to happen in classrooms, teachers will have to teach from a conceptual curriculum. To do so they must be sensitive to children's thinking during instruction and shape their instructional actions accordingly-to ensure that children hear what they intend them to hear. This article examines how one teacher's way of knowing mathematics was reflected in the language he used in teaching concepts of rate to one student during a teaching experiment. The teacher's conceptualizations of rate, although strong and elaborate, were encapsulated in the language of numbers and operations, and this undermined his effort to help the student understand rates conceptually. We examine the teacher's language in light of his intentions and the student's interpretations of the tasks. We discuss implications for instruction that is based on a conceptual curriculum and is sensitive and responsive to children's thinking.
RDF studies of the superionic conductor RbAg4I5 using EXAFS

Abstract Measurements of the extended X-ray absorption fine structure (EXAFS) on the Ag K-shell absorption in RbAg4I5 show that in all three crystalline phases the equilibrium position of the Ag ions is near the center of tetrahedra formed by the iodine atoms. In addition, Ag-Ag correlations, which persist into the superionic α-phase, are observed.
The impact of outsourcing on information technology spending

Abstract Information technology outsourcing (ITOS) is a strategy used by many firms to either reduce their total cost of IT or gain access to IT capabilities not available in-house. A proprietary data set of large US firms is used to examine the effect of ITOS on firm-level IT spending over the seven-year period 1999–2005. Prior research suggested that (1) engaging in ITOS would be associated with a lower level of IT spending and (2) the extent of ITOS would be negatively associated with the level of IT spending. The results did not support either hypothesis. IT outsourcing is associated with higher IT spending, presumably reflecting the costs of enhancing IT capabilities. This increase in IT spending is driven by firms that initially outsource a large percentage of their IT activity. This paper makes three contributions to the literature. First, it is the first study to investigate whether the act of engaging in ITOS is associated with an objective, quantitative measure of IT spending in a large sample of firms over time. Second, it investigates whether the extent of ITOS affects IT spending, i.e., whether a higher level of ITOS has a greater impact on IT spending. Third, it examines IT spending at the aggregate firm level rather than the individual IT project level, providing a broader measure of the impact of ITOS on the IT function.