cssi/SciSciGPT-SciSciNet huggingface dataset:
30-Day Readmission After Spine Surgery: An Analysis of 1400 Consecutive Spine Surgery Patients.

Study design Retrospective cohort review. Objective To identify the rates, causes, and risk factors for 30-day unplanned readmissions in after elective spine surgery at our institution. Summary of background data Early readmission after spine surgery is being used as a proxy for quality of care. One-fifth of patients are rehospitalized within 30 days after spine surgery. Nearly 60% of these readmissions are unplanned, which translates into billions of dollars in healthcare costs. Methods A total of 1400 patients undergoing elective spine surgery at Duke University Hospital between 2008 and 2010 were included in the study. We identified all unplanned readmissions within 30 days of discharge. Unplanned readmissions were defined to have occurred as a result of either a surgical or a nonsurgical complication. Patient records were reviewed to determine the cause of readmission and the length of hospital stay. Results A total of 132 (9.4%) unplanned early readmissions were identified. The mean ± SD age was 58.6 ± 15.1 years. Lumbar decompression and fusion was the most common procedure The most common causes for readmission were infection or a concern for infection (34.8%) and pain (19.7%), and 26.5% of readmissions required a return to the operating room. The majority of patients that were readmitted presented to the emergency department from home (58.0%) whereas 25.2% were readmitted from a skilled nursing facility. The mean ± SD number of days from discharge to readmission was 9.8 ± 7.9 days and the average length of hospital stay for the readmissions was 7.5 days. Conclusion This study suggests that infection and refractory pain were the most common primary reasons for unplanned readmission. Efforts at reducing unplanned early readmission after elective spine surgery should be focused on more effective post discharge care.
Clinical Accuracy of the HipSextant Navigation System

Background: While more than ½ of acetabular components placed during hip arthroplasty are significantly malpositioned, traditional surgical navigation and robotoics have not been widely adopted. This may be due to the additional time, expense, and complexity associated with this technology. As an alternative, smart mechanical navigation instruments, adjusted on a patient-specific basis, have been introduced to address the problem of cup malorientation. The current study assesses the accuracy of acetabular component alignment using a mechanical navigation instrument. Patients and Methods: The acetabular component was aligned in 58 consecutive hips in 58 patients using the HipSextant Mechanical Navigation System (Surgical Planning Associates, Inc. Boston, MA). The technique involves using a patient-specific plan and associated software. In planning for surgery, CT data are used to create a 3D model and to define the anterior pelvic plane (APP). A patient-specific HipSextant docking coordinate system is then determined by three points: one just behind the posterior acetabular rim, a second on the lateral side of the ASIS, and a third on the surface of the ilium (Figure 1). The HipSextant itself has two adjustable orthogonal protractors (in-plane and off-plane angle) and two adjustable arms so that the instrument is adjusted for each patient based on their specific anatomy. The instrument docks directly to the pelvis so the recommended orientation of the acetabular component is based on the actual position of the pelvis at the time of component implantation. A direction indicator points in the direction of the planned cup orientation (Figure 2). Cup alignment was further enhanced with the use of a parallel guide to improve parallel visualization (Figure 3). Postoperative cup orientation was measured using a validated two-dimensional/three-dimensional matching method [3,5]. Results: Cup orientation measurements of the series of 58 THA9s performed in the current study using the mechanical navigation instrument showed an error of inclination of 0.63° ± 2.3° [range, −5.3° to 6.0°] and an error of anteversion of 1.0° ± 2.7° [range, −5.3° to 7.0°]. There were no outliers in either anteversion or inclination. Conclusion: The current study demonstrates that the mechanical navigation instrument shows excellent cup alignment accuracy in a consecutive series of patients. This accuracy, compared to traditional navigation and robotic systems, may be due to the wide-based nature of the docking mechanism and the eliminate of the cumulative errors of registration and tracking inherent to more complex systems.
Physician Charges and Medicare Payments.

The Research Letter by Drs Bai and Anderson reported variation in the ratio of physician charges to Medicare payments by specialty.1 The authors defined any charge greater than Medicare payment as an “excess charge.” However, Medicare payment is not an appropriate benchmark for payment for physicians’ services because it is based only on the federal government’s budget; Medicare payments have no basis in free market principles of valuation of goods and services. In addition, Medicare does not pay all specialties equally compared with commercial, market-based payment. The average payment by Medicare to all specialties is 84% of commercial rates; whereas anesthesiology is paid at only 30.9% of commercial payments. Medicare is known to not pay enough to cover physician’s expenses; therefore, commercial payments must be significantly greater so physician businesses can remain open to provide care.
Doing More With Less: Innovative Program Building in ABA and Special Education in a Rural Setting

There is a need for both special education teachers and Board Certified Behavior Analysts (BCBAs) who are trained to work in rural school settings with students with disabilities and problem behavi...
Surgical Salvage Options in Patients with Recurrent Tumor Following Radiotherapy

Radiation therapy has been effectively utilized in the management of prostate cancer since the early 1900s. Initially, techniques to apply radiotherapy to the prostate utilized implanted radium either transurethrally, transperineally, or transrectally. Although tumor shrinkage occurred, side-effects on adjacent organs limited its benefit. In the 1950s, high-energy supervoltage external beam therapy was introduced by Bagshaw et al. (1965) to the treatment armamentarium. Supervoltage external beam radiotherapy produced marked improvements in tumor control and survival rates without the previously limiting side-effects. Today, radiotherapy continues to play a central role in the management of prostate cancer along with observation, radical prostatectomy and hormonal therapy. As with surgery and other forms of therapy presently available, controversy exists about the long-term efficacy. Prostate cancer is rather unusual in that the disease process is so protracted it is often difficult to ascertain whether a specified therapy has been effective or whether the disease process was not destined to be aggressive.
Medical sequencing of de novo ectodermal dysplasia in identical twins and evaluation of the potential eligibility for recombinant EDA therapy

The purpose of this study was to test two 8-year-old identical twins with ectodermal dysplasia (ED) and their unaffected parents for the presence of mutations in the EDA gene with the hypothesis that they might be carrying a de novo mutation in EDA and potentially eligible for recombinant EDA therapy. DNA was extracted using saliva samples obtained from the identical twin girls and both parents. PCR products of Ectodyplasin A (EDA), Ectodysplasin Receptor (EDAR), Ectodysplasin Receptor Associated Death Domain (EDARADD), and Connexin-30 (GJB6) were sequenced by the Sanger method and the results analyzed using a reference sequence. Exons and exon-intron boundaries of EDA, EDAR, EDARADD, and GJB6 were sequenced in both parents and the affected identical twin pair. No mutations were detected in EDA or GJB6. Genetic variants located in the intron of EDAR were found but determined to be non-contributory to the twins' ED. A microsatellite polymorphism was detected in all four subjects in exon 4 of the EDARADD gene but determined not to be causal to the ED. There was a silent mutation detected in exon 6 of the EDARADD gene of both the daughters and their unaffected mother but also unlikely to be the cause of ED. These results suggest that ED of the subjects is caused by a de novo mutation in a gene not studied here. It is likely these subjects and their future offspring would not benefit from the development of recombinant EDA replacement therapy.
Abstract MP58: Objectively-measured Physical Activity and Incident Cardiovascular Events Among Mobility Limited Older Adults: The Life Study

Introduction: Objective measurement of daily physical activity (PA) is an important predictor of cardiovascular risk among young- and middle-aged adults. However, data are sparse regarding the value of activity monitoring among older adults [[Unable to Display Character: –]] particularly among those with mobility limitations. Hypothesis: We hypothesized that objectively-measured daily PA would be associated with the incidence of cardiovascular (CV) events among older adults in the Lifestyle Interventions and Independence for Elders (LIFE) study [[Unable to Display Character: –]] a Phase 3 randomized clinical trial comparing a structured exercise intervention (median 2.7 years) to health education among mobility-limited older adults. Methods: CV events (myocardial infarction, stroke, cardiovascular death, silent myocardial infarction, angina/symptomatic coronary artery disease, peripheral artery disease, abdominal aortic aneurysm) were adjudicated by medical records review. Free-living activity data were collected by hip-worn accelerometer at baseline and 6, 12, and 24 months post-randomization. Linear regression, adjusted for accelerometer wear time, demographic and cardiovascular disease-related covariates, was used to model the relationship of incident CV events with accelerometry variables (steps/day and minutes/day spent in activity registering ≥ 100 or ≥ 500 counts/minute) at baseline and in a time-dependent fashion. Results: Participants (n = 1618; age 78.9 ± [SD] 5.2 years; 67.2% female) had a cumulative CV event incidence rate of 14.5% (234 events). Event rates did not differ between randomized groups. At baseline, participants registered 2681 ± 1475 steps/day and spent 22.8 ± 8.2% of their time performing activities≥ 100 cts/min and 6.3 ± 4.3% of time in activities ≥ 500 cts/min. At baseline, CV event risk was10% lower for every 500 steps/day (HR: 0.90, 95% CI: 0.84-0.96, p=0.001). Each 30 minutes spent performing activities ≥ 100 cts/min (0.89, CI: 0.83-0.96, p=0.002) and ≥ 500 cts/min (HR = 0.76, CI: 0.65-0.90, p=0.001) was also associated with lower CV event risk. Across all follow-up visits, participants took 2544 ± 1592 steps/day and spent 21.3 ± 8.2% of their time performing activities> 100 cts/min and 5.8± 4.3% of time in activities ≥ 500 cts/min. In time-dependent analyses, both steps/day (HR: 0.92, CI: 0.86-0.97, p=0.004) and duration of activity ≥ 500 counts/min (HR: 0.80, CI: 0.68-0.94, p=0.007) were associated with lower CV event rates. Longitudinal performance of activity ≥ 100 cts/min was not statistically significant (HR: 0.93, CI: 0.87-1.01, p=0.067). Conclusions: Objective measurements of PA collected via accelerometry predicted incident CV events among older adults with limited mobility. These data support the importance of daily PA in this population and suggest that accelerometry may be a useful tool to aid in assessing the risk of CV events.
Surface modification for corrosion resistance

Corrosion of metallic structural materials at elevated temperatures in complex gas environments of coal gasification is a potential problem. The use of appropriate corrosion-resistant coatings on metallic components offers an avenue to minimize material degradation and extend component life. The purpose of this paper is to review the current status on development and performance coatings in environments typical of coal gasification systems. The paper discusses the complexity of gasification environments, coating requirements for acceptable performance, coating methods, and corrosion performance of several of the coatings. Examples illustrate the morphology and corrosion performance of coating/structural alloy combinations exposed in simulated gasification environments and the results are used to identify promising coatings for application in gasification systems.
Sustainable Production: Definition, Comparison, and Application

In what follows, I analyze the various definitions of sustainability that have been established in a diverse set of disciplines – the economics definitions of weak, strong, and environmental sustainability, the ecological definition, and the authoritative definitions enumerated in the Brundtland Report and Agenda 21 – and I argue that strong sustainability is the superior definition of sustainability in terms of production. Applying this definition to industrial firms via policies that harmonize producer actions with sustainable productive activity will require a fundamental readjustment of both producer and consumer behavior. This article is available in The Park Place Economist: http://digitalcommons.iwu.edu/parkplace/vol14/iss1/18 The Park Place Economist, Volume XIV 88
Thomas Nast's Crusading Legal Cartoons

The cartoonist Thomas Nast (1840-1902) was in his heyday a political institution, with each of his pictures helping to form public opinion. His influence reached its height in the late 1860s and early 1870s with his relentless caricatures of Boss Tweed and the Tammany Hall Ring in New York City.One part of Nast’s work not often highlighted but as brilliant as the rest is his legal cartoons. Nast’s best work was done with high moral zeal, and his satire of lawyers and the legal system was no exception. His attacks grew out of frustration with the ineffectiveness of legal remedies against the Ring. He was especially incensed that prominent lawyers such as David Dudley Field not only were willing to represent members of the Ring, but could cleverly exploit legal technicalities of their own making to win advantage. Nast excoriated the corruption and bribery of the bench by the Ring, and also, more generally, the adversarial system as it was developing in America.
Fixed-angle reflectance from uranium compounds and U-bearing minerals: experimental challenges to determine the optical constants n and k

Fixed-angle reflectance spectroscopy using a commercial Fourier transform infrared (FTIR) spectrometer was employed to derive the optical constants n and k of several uranium compounds. This technique relies upon measurement of the quantitative reflectance R(ν) spectra from a polished surface across a broad spectral range (in this case, the mid- and far-IR covering ca. 7500 to 50 cm-1 ) followed by application of the Kramers-Kronig transformation (KKT). Near-normal fixed-angle measurements as used in this technique require continuous reflectance spectra to as low a wavenumber value as possible. Here, we discuss some of the many challenges in measuring the far-IR and very far-IR (terahertz) spectra using an interferometric instrument, particularly those stemming from small sample sizes, typically just millimeters on a face for crystalline samples, as well as limitations due to optical components and diffraction. We apply this method to single-crystal UO2 and its mineralogical form uraninite, as well as other Ubearing minerals such as autunite [Ca(UO2)2(PO4)2·8-12H2O] and the dehydrated form of autunite, meta-autunite. In addition to the specular reflectance spectra, x-ray diffractometry was used as a confirmatory technique to analyze the surface composition of the species. Deriving the infrared optical constants for such U-bearing species (as well as other solids) will enable nondestructive detection under a variety of environmental and compositional conditions.
A decade of writing on Wikipedia: A comparative study of three articles

This article reports what observable writing activities characterized three Wikipedia articles, archive, design, and writing, over a three-year period from 2012–2014. It then compares these results to writing in these same three articles 10 years earlier, from 2002–2004. Results show that articles were longer and more referenced in 2012–2014. The most frequent written contributions in 2012–2014 were adding and deleting content, followed by vandalizing and reverting vandalism. Ten years earlier, content addition was likewise the most frequent activity, though vandalism and its removal were not found. The least frequent written contributions in 2012–2014 were organizing and formatting content. Both activities occurred more often 10 years earlier. The number of contributors grew significantly in 2012–2014, though during both time periods approximately ¾ of participants contributed only once. These results support that writing in Wikipedia continues to support notions of revision and collaboration valued in the discipline of writing studies. However, the revision and collaboration that occurred were limited. Thus, more robust approaches to these concepts are needed when using Wikipedia to teach writing. More broadly, Wikipedia contributors need to focus more on organizing and formatting article content for readers.
La verticalización como régimen urbano. El caso de las ciudades chilenas

The proliferation of high-rise residential buildings in the central and pericentral fabric of the Chilean cities is a recent phenomenon and its intensity leads to ask about the effects it has on the urban interaction. This paper explores the records and accounts giving rise to two different narratives of the verticalization phenomenon: a first one articulated around the surveys of building; and a second one based on press releases telling events in high-rise buildings. Both of them result useful to verify how this phenomenon –occurring under the agency of architectural institutions– becomes an urban regime. That is to say, how it translates into regulations to allow producing modes of order for the interaction in the cities.
Extremity bone sarcoma: Evolution from primary amputation to limb salvage surgery (LSS).

e22012Background: Primary Extremity Bone Sarcomas (PEBS) were historically managed by upfront amputation. Early success rates utilizing neoadjuvant chemotherapy followed by LSS showed promise in ha...
Artificial Intelligence and Liability in Health Care

Artificial intelligence (AI) is revolutionizing medical care. Patients with problems ranging from Alzheimer’s disease to heart attacks to sepsis to diabetic eye problems are potentially benefiting from the inclusion of AI in their medical care. AI is likely to play an ever- expanding role in health care liability in the future. AI-enabled electronic health records are already playing an increasing role in medical malpractice cases. AI-enabled surgical robot lawsuits are also on the rise. Understanding the liability implications of AI in the health care system will help facilitate its incorporation and maximize the potential patient benefits. This paper discusses the unique legal implications of medical AI in existing products liability, medical malpractice, and other law.
Experimental demonstration of a tunable Marchand balun at K band in Silicon Germanium (SiGe) technology

This paper demonstrates the operation of a Marchand balun prototype in a standard Silicon process that can switch its operation between 2 adjacent regions of the K band. Pass gate CMOS switches connect or disconnect additional lengths of line in the windings of the balun to change the balun's frequency response while maintaining its mixed mode performance. Digital control of the balun is enabled by the CMOS switches. The balun is fabricated in a high performance SiGe BiCMOS process built on standard 180 nm CMOS technology and characterized in terms of mixed mode scattering parameters. A broad instantaneous bandwidth is demonstrated with relative long gate length MOS devices. The authors believe that this is the first experimental demonstration of a balun tunable by pass gate switches in the high region of the microwave range.
Transesophageal echocardiographic finding of left atrial appendage lobe mimicking a mass lesion.

We describe an elderly patient undergoing ablation for atrial fibrillation in whom, two-dimensional transesophageal echocardiography showed a mass-like lesion in or adjacent to left atrial appendage (LAA). This mass-like effect was produced by en face visualization of the top of a LAA lobe in the presence of a small effusion in the transverse sinus of the pericardium. (Echocardiography 2011;28:684-685)
Riding the Rhino: Attempting to Develop Usable Legal Standards for Combat Activities

The body of law regulating combat activities is, essentially, a body of preventive law which should be applied in military training, planning, and operations to minimize net human suffering and net destruction of civilian objects in armed conoict. Prosecution for violations of such law is uncommon. Such prosecutions have, however, been conducted before the International Criminal Tribunal for the former Yugoslavia (ICTY). This Article reviews the relevant jurisprudence of the ICTY and asserts that effective prosecution for combat offences, such as unlawful attacks, can be conducted before non-specialist tribunals and that these prosecutions can both strengthen the law and elaborate upon its substantive provisions.
Integral Equation Method for Subsonic Flow Past Airfoils in Ventilated Wind Tunnels

The method of contour distribution of sources and vortices, used to calculate potential flows about twodimensional airfoils in free air, is extended to flows around airfoils under the constraint of ventilated wind tunnel walls. Based on the concept of fundamental solutions, the source and vortex singularities are modified to satisfy the boundary conditions at the walls. The application of the airfoil boundary condition reduces the problem to a Fredholm integral equation of the second kind for the source density function. The numerical solutions obtained by a finite element technique are in good agreement with experimental results. I. Introduction A LARGE part of established wall interference theory is based on the simplifying assumption that the wall effects can be evaluated from an estimated far flowfield of the model, considering only the wind tunnel wall boundary condition. The result is interpreted in terms of modifications to the freestream. If the model is small enough, these can be expressed as corrections to the direction and speed of the stream, constant over the model (the angle of attack and Mach number corrections). If the model has appreciable length, a more refined interpretation, involving the streamline curvature and buoyancy (pressure gradient) effects, is required. The model boundary condition enters the problem only in the final stage, if there is a need to evaluate the wall effects in terms of model quantities, such as the surface pressure distribution, aerodynamic forces, moments, etc. A comprehensive account of this approach, its applicability and limitations is given in Ref. 1. It is perhaps worth emphasizing that the above concept
The Wavenumber-Frequency Spectrum of the Wall Pressure Field Computed from a Numerical Solution of the Navier Stokes Equation

The wall pressure fluctuations in a turbulent channel flow have been calculated from a numerical solution of the full Navier Stokes equation. No closure or subgrid scale approximations have been made. The wavenumber-frequency spectra of the pressure fluctuations obtained in this work show the following characteristics of particular note: (a) a “convective ridge” associated with those components of the pressure fields propagating in the streamwise direction and at a significant fraction of the free streamvelocity; (b) comparable dimensions of the wall pressure structure in the streamwise and spanwise directions; (c) a nonzero value of the pressure spectrum at zero wavenumber. This last result is shown theoretically to be a consequence of the boundary conditions associated with a channel flow.
Cloning and sequencing of Escherichia coli mutR shows its identity to topB, encoding topoisomerase III.

Abstract We have cloned and sequenced the mutR gene from Escherichia coli, which results in an increased frequency of spontaneous deletions, by using a strain carrying a Tn10 derivative inserted into mutR. The analysis of 1,286 bp of mutR sequence shows that this gene is identical to the topB gene, which encodes topoisomerase III. The increased deletion formation is the first reported phenotype for cells lacking topoisomerase III, and this suggests that topoisomerase III is involved in reactions that normally reduce the levels of spontaneous deletions.
Response of Cultured Maize Cells to (+)-Abscisic Acid, (-)-Abscisic Acid, and Their Metabolites

The metabolism and effects of (+)-S- and (-)-R-abscisic acid (ABA) and some metabolites were studied in maize (Zea mays L. cv Black Mexican Sweet) suspension-cultured cells. Time-course studies of metabolite formation were performed in both cells and medium via analytical high-performance liquid chromatography. Metabolites were isolated and identified using physical and chemical methods. At 10 [mu]M concentration and 28[deg] C, (+)-ABA was metabolized within 24 h, yielding natural (-)-phaseic acid [(-)-PA] as the major product. The unnatural enantiomer (-)-ABA was less than 50% metabolized within 24 h and gave primarily (-)-7[prime]-hydroxyABA [(-)-7[prime]-HOABA], together with (+)-PA and ABA glucose ester. The distribution of metabolites in cells and medium was different, reflecting different sites of metabolism and membrane permeabilities of conjugated and nonconjugated metabolites. The results imply that (+)-ABA was oxidized to (-)-PA inside the cell, whereas (-)-ABA was converted to (-)-7[prime]-HOABA at the cell surface. Growth of maize cells was inhibited by both (+)- and (-)-ABA, with only weak contributions from their metabolites. The concentration of (+)-ABA that caused a 50% inhibition of growth of maize cells was approximately 1 [mu]M, whereas that for its metabolite (-)-PA was approximately 50 [mu]M. (-)-ABA was less active than (+)-ABA, with 50% growth inhibition observed at about 10 [mu]M. (-)-7[prime]-HOABA was only weakly active, with 50% inhibition caused by approximately 500 [mu]M. Time-course studies of medium pH indicated that (+)-ABA caused a transient pH increase (+0.3 units) at 6 h after addition that was not observed in controls or in samples treated with (-)-PA. The effect of (-)-ABA on medium Ph was marginal. No racemization at C-1[prime] of (+)-ABA, (-)-ABA, or metabolites was observed during the studies.
Sequence comparisons of A/AA/6/60 influenza viruses: mutations which may contribute to attenuation

Influenza virus infection is a worldwide public health threat. Cold-adaptation was used to develop a vaccine line (ca A/AA/6/60 H2N2) which promised to reduce the morbidity and mortality associated with influenza and to serve as a model for other live virus vaccines. This study establishes that two distinct lines of wt A/AA/6/60 viruses exist with different phenotypic and genotypic characteristics. The two virus lines have the same parent but different passage histories. The first line is both temperature sensitive (ts) and attenuated in ferrets and the second line (after multiple passages in chick kidney cells, eggs and mice) is non-ts and virulent in ferrets. Both lines of viruses have been further differentiated by sequence analysis. We have identified point mutations common to all virulent viruses but absent from the attenuated viruses. This was accomplished by comparing the nucleotide sequences of the six internal genes in three different attenuated passages of A/AA/6/60 with those of five different virulent passages of the same virus. The corresponding nucleotides of the attenuated viruses, therefore, represent candidate attenuating lesions: 6 in the basic polymerase genes (5 in PB1, 1 in PB2), 2 in the acidic polymerase gene (PA), 1 in the matrix (M) gene, 2 in the non-structural (NS) gene, and none in the nucleoprotein (NP) gene. Two of the 5 attenuating lesions in PB1 are silent; 1/2 in PA is silent; and 1/2 in NS is silent. Further changes which might be identified by comparing nucleotide and amino acid sequences of the A/AA/6/60 viruses with those of other influenza viruses may also contribute to the attenuation of the ca virus. Our study identifies nucleotides which more precisely define virulence for this virus and suggests that growth of the virus at low temperature may have preserved a non-virulent virus population rather than attenuating a virulent one.
Off-road cycling injuries. An overview

Off-road bicycles, commonly called ‘mountain bikes’, have become increasingly popular worldwide since their introduction in the western US in the late 1970s. This popularity is partly because these vehicles can be ridden on a wide variety of terrain which is not accessible to other types of bicycle. Although early versions were rather crude, off-road bicycles today typically include high strength, lightweight frames with a wide array of available suspension and braking systems. Virtually all aspects of the technology continue to evolve, including components and protective equipment. As the popularity of off-road cycling has increased, so too has the interest and level of participation in the competitive aspects of the sport. Currently, 2 organisations — the National Off-Road Bicycle Association (NORBA) and the Union Cycliste Internationale (UCI) — sponsor the major events within the US and around the world. To date, the majority of studies have been descriptive in nature, with data collected via self-report, questionnaire formats. Only 1 prospective study has been reported thus far, which surveyed a major international competition held in the US in 1994. Injury rates calculated on the basis of injuries per ride or event in competitive venues have been reported, ranging from 0.2 to 0.39% compared with 0.30% for recreational participants. Retrospective data collected from recreational and competitive riders indicate that from 20 to 88% of those surveyed reported having sustained an injury during the previous year of participation. The majority of injuries appear to be acute, traumatic episodes involving the extremities, with contusions and abrasions being the most common. In general, the incidence of more severe injuries such as dislocations, fractures and concussions is low. Comparisons between road and off-road cycling events indicate that off-road cyclists sustain more fractures, dislocations and concussions than their road-event counterparts. Future research should incorporate epidemiological methods of data collection to determine the relationships between vehicle design, terrain and safety equipment and riding-related accidents. Further, those engaged in such research should attempt to set a standard definition for injury.
An Electrochemical Supersandwich Assay for Sensitive and Selective DNA Detection in Complex Matrices

In a traditional sandwich assay, a DNA target hybridizes to a single copy of the signal probe. Here we employ a modified signal probe containing a methylene blue (a redox moiety) label and a "sticky end." When a DNA target hybridizes this signal probe, the sticky end remains free to hybridize another target leading to the creation of a supersandwich structure containing multiple labels. This leads to large signal amplification upon monitoring by voltammetry.
The migma principle of controlled fusion

Abstract The principles for a continuously operating, nonplasma, nonthermal, fusion power source are presented. The fuel is a 2 MeV deutron beam which is injected, “debeamed” and “self-collided” through precession; the d-d reaction breeds a 3 Hed self-colliding mixture (“migma”) which is the main source of fusion power. Because of continuing replenishment, the migma does not become Maxwellian. Direct conversion of fusion energy into electricity is accomplished by deceleration of the positively charged ions (fusion products). An elemental power source (“migmacell”) that can be built within the bounds of available technology would have a radius of 5 cm and deliver between 10 mW and 10 W of net electric power, depending on the assumptions on the space-charged limit. Ideas to increase the net power output, including local macro-neutralization, are indicated. We outline various ways to combine a large number of the migmacells into a 3-dimensional matrix to make a reactor capable of generating 10 kW of electric power.
Membrane transport in Schistosoma mansoni: transport of amino acids by adult males.

Abstract The mechanisms by which adult male Schistosoma mansoni transport amino acids have been investigated using radioactive amino acids during 2-min incubation times. The transport constants (Kt) for mediated uptake of glycine, proline, methionine, arginine, glutamate, and tryptophan were calculated to be 0.60-1.05, 1.67-1.98, 2.0, 0.10-0.35, 0.30-0.50, and 0.5-1.0 mM, respectively. Maximal velocities (Vmax) were 5.5–7.5, 25, 6.4, 1.5-2.0, 2.5, and 3.0–6.0 μmoles absorbed/g worm protein/2 min, respectively. Cysteine is taken up solely by diffusion. Proline uptake is unique in that no significant diffusion component was found. The other amino acids studied were absorbed by diffusion as well as by specific transport systems. In the 2-min incubation periods employed glycine, proline, glutamate, and methionine were not significantly metabolized indicating that the uptake studies using these substrates reflect transport. Metabolism of the other amino acids used in these studies was not examined. The specificity of the transport systems was studied by testing the inhibitory effects of various amino acids on the uptake of each of the amino acids studied. The results suggest the presence of at least five transport systems. There is a highly specific transport locus for proline, and one for acidic amino acids. There are probably at least two transport systems, each of broad and overlapping specificity, for most of the neutral amino acids. Basic amino acids also appear to be taken up by complex transport systems, at least one of which overlaps with the neutral sites. The results are discussed with respect to the nutrition of the parasite and the host-parasite relationship.
Determination of the pressure-volume-temperature ( PVT) surface of Isopar-M: a quatitative evaluation of its use to float deep-sea instruments

Abstract A method is described for determining pressure-volume isotherms of liquids at high pressures. A volumometer without a ground glass joint is used. The pressure-volume-temperature ( PVT ) surface of Isopar-M has been determined, and shows that this hydrocarbon liquid is suitable for floats to 1100 bars at 0°C. The so-called Tait equation has been used as the equation of state for the PVT values.
Elementary teachers’ beliefs about joining a professional science teachers organization

(1993). Elementary teachers’ beliefs about joining a professional science teachers organization. Journal of Science Teacher Education: Vol. 4, No. 4, pp. 115-120.
Quantitative Characterization of Aqueous Suspensions using Variable-Angle ATR-FTIR Spectroscopy: Determination of Optical Constants and Absorption Coefficient Spectra

In one step further toward developing ATR-FTIR (attenuated total reflection-Fourier transform infrared) spectroscopy as a quantitative technique to interpret interfacial phenomena in aqueous colloidal suspensions, we have used variable angle ATR spectroscopy to concurrently determine the Kramers−Kronig integration constant (or anchor point, nr) and spectra of the optical constants (refractive index, n, and absorption index, k) for α-FeOOH and TiO2 (anatase) aqueous suspensions. In addition, the absorption coefficient (a) spectra were calculated from the k spectra. The suspension conditions (pH, ionic strength, and concentration) were such that the samples were homogeneous over the sampling depth of the IR radiation, behaving as a thick film for ATR. This study shows that discrepancies in the value of the refractive index of a suspension and its corresponding supernatant generate distortion in the regions of strong water absorption of the ATR difference spectra (suspension spectrum-supernatant spectrum). T...
SUBSTANCE USE ESTIMATES FROM RDD AND AREA PROBABILITY SAMPLES IMPACT OF DIFFERENTIAL SCREENING METHODS AND UNIT NONRESPONSE

Survey mode effects linked to unit nonresponse and screening procedures were estimated in a study of self-reported tobacco, alcohol, and illicit drug use. Two samples of the same population were drawn : a random digit dial (RDD) sample with telephone screening and a multistage area probability sample with in-person screening. Respondents in both samples were interviewed by telephone to control mode of communication effects. Households without telephones were excluded from both samples to control sample coverage effects. Although results show substantially lower response rates in the telephone survey due to screening refusals, the two survey procedures produced samples that were very similar in demographic characteristics and in substance use profiles. Differential screening operations and differential nonresponse rates between the RDD and area probability designs did not appear to be a major source of mode effects in comparing telephone and face-to-face surveys of substance use
Potters’ marks and social relations of ceramic distribution in the Oyo Empire

A recently collated inventory of potters' marks in the Oyo ceramic complex of southwestern Nigeria provides important insights into the social relations of ceramic production in the Oyo Empire during the Atlantic Age. Focusing on the serving and cooking bowls excavated in the imperial colony of Ede-Ile, this paper examines the formal and social aspects of potters' marks in the production and circulation of utilitarian vessels, as well as in the forging of an integrated and corporeal imperial identity from the early 1600s to the 1820s. The study draws attention to an important ceramic attribute that has, until now, gone unnoticed in the archaeology of Oyo Empire and in Yoruba Studies in general. It highlights the salience of potters’ marks for understanding the social, political and economic processes in Yorubaland during the mid-Atlantic age.
The Uses of Longitudinal Data and Person-Centered Analyses in the Study of Cognitive and Language Development

Researchers in the fields of cognitive and language development have made less use of large-scale longitudinal designs and of person-centered approaches to data analysis than have researchers in the fields of social and personality development. It is argued that differences among domains of developmental psychology in the research methods employed reflect traditional differences in the goals of these fields. The study of cognitive and language development has sought primarily to discover the universals of development and their underlying mechanisms, whereas the fields of social and personality development have been more concerned with explaining differences in developmental trajectories and outcomes. A selective review of studies of cognitive and language development illustrates this connection between research questions and research methods. It is suggested that as research on cognitive and language development increasingly focuses on individual and group differences, scholars in these fields might profitably make greater use of large-scale longitudinal studies and of person-centered approaches to data analysis.
Suppression of transverse instabilities in a laser by use of a spatially filtered feedback

The effect of a spatially filtered negative feedback on a laser that supports many transverse modes is studied. The Lyapunov theorem is used to find an analytical expression of the parameter domain in which the laser can be stabilized in the plane-wave state by the feedback. The prediction of the Lyapunov theorem is compared with that of the Routh–Hurwitz criterion and is verified by the results of numerical simulation. The numerical studies also show that the spatially filtered feedback can direct the laser to the plane-wave state from a distant initial state.
NO and NOx interactions with group 8 metalloporphyrins

Abstract There has been an ongoing interest in the reactions of nitric oxide (NO) with heme model compounds, with the goal of interpreting related reactions occurring in biology. With recent evidence that higher oxides ( NO 2 - , NO 2 , N 2 O 3 , etc.) may also be formed under bioregulatory conditions, there is a need to understand the reactivities of these compounds with such models. This review discusses the mechanistic studies of the reactions of iron, ruthenium, and osmium metalloporphyrin complexes with NO and the higher nitrogen oxides.
Application of refrigeration system in electronics cooling

An experimental investigation of the transient response of the vapor compression refrigeration (VCR) system to rapid change in evaporator (simulated electronics) heat load is presented. In this study, the VCR system is designed and constructed specifically for applications to cool high heat flux electronics and high-end computers. Temperature and pressure data were measured at pre-selected locations to study the behavior of the refrigeration system to alterations in evaporator heat load. Results show that the VCR system maintains the junction temperature of the simulated electronics at a much lower temperature compared to conventional air-cooling systems. The maximum temperature was registered near the exit of the evaporator cold plate. Experimental evidence shows an oscillation in temperature with time at the evaporator cold plate and the thermostatic expansion valve prior to attaining steady-state condition, and that the thermostatic expansion valve and the evaporator time constants are equal; and have a value of 70 s. Also, for analytical and numerical models of heat transfer in evaporator cold plate, results shows that the assumption of one-dimensional temperature distribution is unrealistic.
Kinetics of Mitochondrial Complementation

Mitochondrial complementation (enhancement of oxidative activity of mitochondrial occured when mitochondria of some inbrveds of eron were mixed in vitro. It was found that mixtures composed of various proportions of mitochondria of inbreds exhibited complementation. Extracts of mitochondria of one inbred did not promote complementation when they were added to infact mitochondria of inbreds exhihited complententation. Extracts of mitochondria of on einbred did not promote complementation when they were added to infact mitochondria of the second inbred. Serial dillutions of mixtures resulted in a rapid reduction of mitochondrial oxidation (QO2 N) suggesting that intimale association between mitochondria was minimized by the dilution and that this decreased complementation. Similar dilutions of mitochondria from inbreds did not decrease their specific activity. Kinetics of mitochondrial oxidation were measured polarographically and it was found that complementation was measurable immediately (1 min) following the mixing. This suggested that physical contact between mitochondria was necessary for complementation.
Electron field emission properties of vertically aligned carbon nanotube point emitters

Abstract We fabricated vertically aligned carbon nanotube (CNT) point emitters directly on Cu wires with flat or sharp tips. The nanostructures and field emission properties of the two kinds of emitters were investigated. Both emitters showed vertically aligned, multi-walled bamboo-liked CNT structures and demonstrated good field emission properties. The emitter on the Cu wire with a flat tip (F-tip) attained an emission current of 70 μA at 4200 V whereas the emitter on the Cu wire with a sharp tip (S-tip) reached an emission current of 65 μA at 3700 V. Both of them demonstrated excellent field emission stability for 40 h at emission currents of about 40 μA and 10 μA for the F-tip and S-tip emitters, respectively.
Autonomous Bifurcations of a Simple Bimolecular Surface-Reaction Model

A pair of ordinary differential equations describing the Langmuir-Hinshelwood mechanism of a bimolecular surface reaction is presented as a simple model for a heterogeneously catalysed chemical reaction. Numerical and analytical techniques are combined to determine the possible dynamics of this model, which, even though it consists only of low-order polynomials, exhibits very complicated behaviour. This includes sustained oscillations, which appear or disappear at Hopf bifurcations, turning points on periodic branches, global homoclinic and metacritical Hopf bifurcations and codimension-two bifurcations with double eigenvalues of zero. The emphasis of the presentation is on geometrical representation of the observed dynamics.
Host selection and responses to forest fragmentation in acorn weevils: inferences from dynamic occupancy models

Prior studies on species-specific responses to habitat alteration have demonstrated that niche breadth is positively associated with patch occupancy rates in landscapes fragmented by agriculture. However, these studies generally have focused on vertebrates and relied upon data collected at a single point in time, neglecting dynamic processes that could alter inferences. We studied the effects of host selection and forest fragmentation on population dynamics of acorn weevils Curculio, the primary insect seed predators of oaks in North America. Detection/non-detection data were collected from 174 red and white oaks in 19 forested fragments from 2005–2008. We used dynamic multi-season site-occupancy models within a Bayesian framework to explore variation in patch (tree-level) occupancy dynamics of three species of weevils that vary in their specialization, i.e. their relative selection of red and white oak as hosts: C. pardalis (white oak specialist), C. sulcatulus (generalist) and C. proboscideus (generalist). Contrary to expectations, the specialist exhibited greater estimated rates of occupancy than generalists. However, red oak trees occupied by the white oak specialist appeared to function as sink populations maintained by frequent colonization following local extinction. Specialists also exhibited greater relative variation in occupancy and relative abundance on their host trees among years. Generalists exhibited lower local extinction and colonization rates than the specialist. Occupancy and vital rates of weevils on a host tree increased with acorn production and were significantly influenced by neighborhood forest density. Our results suggest that across much of their range in the eastern United States acorn weevils exist in fragmented, temporally dynamic landscapes, with generalists occurring on a lower proportion of usable trees but buffered by access to more suitable patches and greater patch-specific survival. More generally, our results demonstrate that estimates of specialization derived from occupancy data may be misleading in the absence of patch-specific information on vital rates. Landscapes of the midwestern United States have undergone dramatic changes in the past two centuries, mainly due to anthropogenic conversion of vast deciduous forest lands and prairies for agriculture and urban areas. For instance, Indiana and neighboring states together have lost more than 60% of forests and 99% of prairies since the pre-European settlement period (Smith et al. 1994, Robertson et al. 1997). Indiana’s forest lands alone have lost nearly 80% of their original area in the past 150 years (Miller 1993). Remnant forest stands are embedded in a matrix of agriculture and residential development and vary widely in size, shape, edge:perimeter ratios and levels of isolation.