cssi/SciSciGPT-SciSciNet huggingface dataset:
The risks of pedicle wall breech with larger screws after undertapping.

Abstract Background context A linear relation exists between the insertional torque when placing a screw and the ultimate screw pullout strength; therefore, undertapping of the pedicle followed by insertion of a larger screw may enhance the pullout strength of the screw. Purpose To report the risk of pedicle wall breech with placement of 6.2-mm pedicle screws after undertapping with a 5.2-mm tap and to evaluate the effectiveness of direct visualization to identify these breeches. Study design/settings Prospective evaluation of risks of pedicle wall breech with undertapping for a larger screw and the utility of directly visualizing pedicle walls during access and placement of pedicle screws for evidence of breech. Patient sample Sixty-five consecutive patients. Outcome measures Intraoperative direct visualization of pedicle wall breech. Postoperative radicular leg symptoms. Methods We prospectively analyzed placement of pedicle screws in sixty-five consecutive patients during lumbar-instrumented fusions after laminectomies performed by a single spine surgeon. Forty-four patients were primary fusions, and 21 were revisions. Twenty-seven were male, and 38 were female, with a mean age of 54.7 years (range, 15–85 years). Four hundred twenty-eight total pedicle screws were placed for an average of 6.6 screws per patient (range, 2–12 screws). Results The incidence of pedicle wall breech during access was 0.7% (3/428) and 1.6% (7/428) after screw placement. 71% (5/7) of the screw breeches were noted with direct inspection of the pedicles intraoperatively, and 29% (2/7) were identified on postoperative X-ray films as lateral breakthroughs that were missed on intraoperative fluoroscopy and direct visualization. Therefore, 100% of misplaced screws potentially harmful to nerve roots were identified on direct visualization. Eighty percent occurred from L2–4. Conclusions This study provides evidence that undertapping of pedicles followed by placement of a larger diameter pedicle screw may breech the pedicle cortices. Although the risk is low, the authors recommend direct visualization of the pedicle walls during screw placement to identify caudad, medial, and cephalad breeches. This technique is for open laminectomies and should be added to the armamentarium of other techniques and not as a replacement.
Clustering in A=10 nuclei

We discuss the identification and properties of the states that belong to the highly clustered rotational band in A=10 nuclei, 10Be, 10B(T=1) and 10C. The band is of interest because it may correspond to an exotic α:nn:α configuration.
Graphic modelling technique for software execution time estimation

Abstract Most performance analysis tools in existence today are closely associated with traditional programming languages. Hence a user cannot model a software system using a performance modelling technique directly. The paper considers this problem and presents a graphic modelling technique for software performance analysis. Also a software tool called Graphic Performance Analysis System (GPAS) is developed that accepts the software's model in a graphical form independent of any programming language and uses it to carry out the performance analysis process.
The quantitative histochemistry of enzymes of the pentose phosphate pathway in the central nervous system of the rat.

— Methods are presented for the measurement of the non-oxidative enzymes of the pentose phosphate pathway in freeze-dried samples of tissue weighing 2 μg or less. The activities of transketolase (EC 2.2.1.1), transaldolase (EC 2.2.1.2), ribosephosphate isomerase (EC 5.3.1.6), and ribulosephosphate epimerase (EC 5.1.3.1), together with glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (EC 1.1.1.44) have been measured in seven specific regions in the central nervous system of the rat. Michaelis constants and temperature coefficients of these enzymes were obtained on homogenates of whole rat brain. The entire enzymic complement of the pentose phosphate pathway was detected in each of the regions examined. The activities of the non-oxidative enzymes and 6-phosphogluconate dehydrogenase did not vary greatly among the different regions examined, whereas the activity of glucose-6-phosphate dehydrogenase varied in close correspondence with the lipid content of the various structures. The cellular, granular layer of the cerebellum was exceptional, since it exhibited at least three times more transaldolase activity than that observed in other structures, an observation suggesting an association of transaldolase with nerve cell bodies.
Molecular regulation of CD40 gene expression in macrophages and microglia.

Abstract Inflammatory events in the central nervous system (CNS) contribute to the disease process in a variety of neuroinflammatory diseases such as multiple sclerosis (MS), Alzheimer’s Disease (AD), and cerebral ischemia, and activated macrophages/microglia are central to this response. Immunological activation of these cells leads to the production of a wide array of cytokines, chemokines, matrix metalloproteinases and neurotoxins, and ultimately to glial/neuronal injury and death. The CD40 molecule has an important role in promoting inflammatory responses by macrophages/microglia, since interaction with its cognate ligand, CD154, leads to secretion of cytokines and neurotoxins. Aberrant CD40 expression by macrophages/microglia, induced by cytokines such as IFN-γ and TNF-α, contributes to neuroimmunologic cascades in the CNS. Strategies to suppress CD40 expression may attenuate inflammation and neuronal damage within the CNS, which will ultimately be of benefit in neuroinflammatory diseases. The mediators that regulate expression of CD40 in macrophages/microglia (both induction and inhibition) function at the level of gene transcription. In this review, we present an overview of the molecular basis of CD40 expression in macrophages/microglia. The signal transduction pathways and transcription factors employed by IFN-γ and TNF-α to induce CD40 expression are described, as are the cis -elements in the CD40 promoter that are critical for CD40 transcription. Information is provided on the mechanism(s) underlying suppression of CD40 in macrophages/microglia by immunomodulatory agents such as IL-4, TGF-β, neuropeptides, neurotrophins, and statins. A comprehensive assessment of CD40 production and function in macrophages/microglia will establish the foundation for future therapeutic manipulation of this critical immunoregulatory protein.
A Chick Vitamin D Assay Method Using Radioactive Calcium (Ca45)

Abstract LIMITATIONS of the chick bone ash and chemical methods for assay of vitamin D are well established. The chick bone ash method requires approximately 4 weeks and large amounts of labor. Chemical methods used for determination of vitamin D are limited to concentrations of the vitamin D active compound or to chemical reactants which will produce a chemical change such as color and therefore may lack specificity. Vitamin D influences the absorption of calcium from the digestive system of the chick, and also the deposition of Ca45 in the tibiae of the chick can be used as an index of percentage absorption (Migicovsky and Emslie, 1949Migicovsky and Emslie, 1950). Simplified, our experiments on a chick vitamin D assay method using radioactive calcium, involved a quantitative comparison of influence of graduated amounts of vitamin D on Ca45 bone mineralization values; bone mineralization values being the percentage Ca45 of a single dosage of radioactive …
Classroom communities' adaptations of the practice of scientific argumentation

Scientific argumentation is increasingly seen as a key inquiry practice for students in science classrooms. This is a complex practice that entails three overlapping, instructional goals: Participants articulatetheir understandings and work to persuadeothers of those understandings in order to make sense of the phenomenon under study (L. K. Berland & B. J. Reiser, 2009). This study examines the argumentative discussions that emerged in two middle school science classrooms to explore variation in how the goals of sensemaking and persuasion were taken up. Our analyses reveals that each classroom engaged with these two goals but that they did so quite differently. These differences suggest that the students in each class had overlapping but different interpretations of argumentation. In addition, comparing across the class' arguments suggests these two goals of scientific argumentation may be in tension with one another. © 2010 Wiley Periodicals, Inc. Sci Ed95: 191–216, 2011
Systemic drug interactions with topical glaucoma medications

Topically administered ophthalmic medications are capable of attaining clinically important serum concentrations, as evidenced by the variety of systemic side effects they can produce. These drugs are therefore also capable of interacting with other drugs administered orally and intravenously. This is especially important when medications are administered to an elderly population, who are often receiving multiple medications. The Physician's Desk Reference and the United States Pharmacopeia Drug Information directory contain numerous warnings of potential interactions between topical glaucoma medications and systemically administered drugs. Unfortunately, literature supporting such interactions is limited, both in quantity and quality, being anecdotal in many cases. This report summarizes available information regarding the nonocular interactions between topical ophthalmic glaucoma medications and other systemically administered medications. Clinical evidence of these interactions is lacking in many cases.
A Comparison of Constant Fraction and Leading Edge Timing with NaI(Tl) Scintillators

The technique of constant fraction of pulse height is shown to be useful for timing with NaI(Tl) scintillators. A comparison of the results of constant fraction timing with leading edge timing indicates that the two techniques are equivalent for small dynamic ranges. For large dynamic ranges constant fraction timing is shown to be a significant improvement over leading edge timing. Also, constant fraction timing over narrow dynamic ranges represents an improvement of 13.7 over the slow crossover timing with NaI(Tl) as reported by Bell. Multiple time sampling is used to investigate how much time information is contained in a NaI(Tl) scintillator pulse. Since an additional time sample represents an improvement of only 11 percent over a single constant fraction measurement, it is concluded that a system more sophisticated than constant fraction will not significantly improve the time resolution.
Association of heart rate response with scan and left ventricular function on adenosine myocardial perfusion imaging

To evaluate the association of heart rate (HR) response with abnormal scan and/or left ventricular (LV) function in patients undergoing adenosine myocardial perfusion imaging, we retrospectively studied 188 consecutive patients who underwent a standard adenosine stress test (without exercise) and myocardial perfusion imaging (MPI) using technetium-99m sestamibi radioisotope. Change in HR was calculated by subtracting HR at rest from peak HR. The percentage change in HR was calculated. All patients underwent stress and resting single-photon emission computed tomography (SPECT) imaging. LV ejection fraction (EF) was calculated using gated SPECT. Mean age was 60 ± 12 years and 135 of the patients (72%) were women. We divided the patients into 2 groups: group 1 (142 patients, 75%) had normal scans and group 2 (46 patients, 25%) had abnormal scans; abnormal scans were defined as presence of either fixed defects, reversible defects, or both. Average HR increased by 29 beats/min in the normal scan group compared with 19 beats/min in the abnormal scan group (p = 0.0004). Forty-seven patients (25%) had reduced EF (<45%). This group had an average HR and percentage HR increase of 20 beats/min (29%) compared with an increase of 29 beats/min (44%) in patients with normal EF (p = 0.002 and p = 0.002, respectively). Thus, a diminished HR response had a significant association with both an abnormal scan and reduced EF on adenosine MPI.
Changes in adiabatic invariants

Abstract The change δJ in the action is calculated for a harmonic oscillator with a slowly varying frequency ω( t λ ) , λ ⪢ 1. First δJ is expressed exactly in terms of the reflection and transmission coefficients associated with ω( t λ ) . Then these coefficients are calculated asymptotically for λ large. It is assumed that ω2 is an analytic function of z = t λ in a neighborhood of the real axis containing two real or two complex conjugate zeros. The result shows that δJ = O(1) when the zeros are real and δJ ∼ Ke−παλ when the zeros are complex, in which case J is an adiabatic invariant. The constants α and K are calculated.
MOTOR UNIT POOL ORGANIZATION EXAMINED VIA SPIKE TRIGGERED AVERAGING OF THE SURFACE ELECTROMYOGRAM

Voluntary muscle force control is accomplished both by recruitment of motor units (MUs) and by firing rate modulation of active MUs. Typically, MU recruitment and firing rate organization is assessed using piecemeal intramuscular recordings drawn from different experiments, or even from different subjects. As a consequence, it is often difficult to assemble a systematic description of the relations between the different MU properties relevant to the control of muscle force. To address this gap, the objective of our current study was to characterize recruitment and firing rate organization of multiple MUs of differing action potential size, recorded simultaneously from the first dorsal interosseous muscle of intact human subjects, using a recently developed surface electromyogram (EMG) sensor array recording and decomposition system (Delsys). We sought to assess the relation between putative MU size and the recruitment and firing properties for these MUs, recorded at different muscle contraction levels. Spike-triggered averaging (STA) of the surface EMG was performed to estimate the action potential sizes using the firing times of discriminated MUs as the event triggers. The results show that the size principle, which relates MU size to recruitment rank order, was clearly evident during individual force contractions. In addition, the mean firing rate across MUs decreased with increasing size of the MU action potential and was also inversely proportional to the recruitment threshold force. We propose that surface EMG recordings together with advanced decomposition systems, combined with STA methods, may provide an efficient way to systematically examine MU pool organizational properties.
The usability of passphrases for authentication: An empirical field study

In developing password policies, IT managers must strike a balance between security and memorability. Rules that improve structural integrity against attacks may also result in passwords that are difficult to remember. Recent technologies have relaxed the 8-character password constraint to permit the creation of longer pass-''phrases'' consisting of multiple words. Longer passphrases are attractive because they can improve security by increasing the difficulty of brute-force attacks and they might also be easy to remember. Yet, no empirical evidence concerning the actual usability of passphrases exists. This paper presents the results of a 12-week experiment that examines users' experience and satisfaction with passphrases. Results indicate that passphrase users experienced a rate of unsuccessful logins due to memory recall failure similar to that of users of self-generated simple passwords and stringent passwords. However, passphrase users had more failed login attempts due to typographical errors than did users of either simple or highly secure passwords. Moreover, although the typographical errors disappeared over time, passphrase users' initial problems negatively affected their end-of-experiment perceptions.
Diversity in New World Stenocranine Planthoppers (Hemiptera: Delphacidae)

ABSTRACT. The diversity of stenocranine planthoppers and their reported host plants is reviewed and discussed with particular reference to the New World fauna. A new species of Obtusicranus and two new genera (Frameus n. g. with 5 new species, Tanycranus n. g. with 1 new species) are described and illustrated. These taxa are the first stenocranine planthoppers known from Mexico and South America. Members of Frameus and Tanycranus are remarkable for having a greatly elongated head. A key to New World genera of stenocranine planthoppers and keys to species for the genera Obtusicranus and Frameus are provided. Stenocranus maculipes (Berg) described from Argentina is not a stenocranine, but is in the Delphacini and is here referred to incertae sedis. Stenocranus luteivitta (Walker) is not a Stenocranus, and is here referred to Delphacodes. The specimen reported by Hamilton (2006) from Illinois as the Asian genus Terauchiana is here found to be Kelisicranus arundiniphagus.
Projected Tikhonov Regularization of Large-Scale Discrete Ill-Posed Problems

The solution of linear discrete ill-posed problems is very sensitive to perturbations in the data. Confidence intervals for solution coordinates provide insight into the sensitivity. This paper presents an efficient method for computing confidence intervals for large-scale linear discrete ill-posed problems. The method is based on approximating the matrix in these problems by a partial singular value decomposition of low rank. We investigate how to choose the rank. Our analysis also yields novel approaches to the solution of linear discrete ill-posed problems with solution norm or residual norm constraints.
Results of measurements of the response of a delta-doped CCD to neutral and charged particle beams

Abstract We report the measurements of the response of a delta-doped Charge Coupled Device (CCD) in imaging mode to beams of charged and neutral particles. That is, the detector imaged the incident beam over its 1024 × 1024 pixels, integrating the number of particles counted in each pixel during the exposure period. In order to count individual particles the exposure time would have had to be reduced considerably compared to the typical ⩾5 s used in these studies. Our CCD thus operated in a different manner than do conventional particle detectors such as the CEM and MCP that normally are used in a particle counting mode. The measurements were carried out over an energy range from 0.8 to 30 keV. The species investigated include H, H + , He + , N + , N 2 + , and Ar + . The energy and ion mass covered wider ranges than previous measurements for the CCD. The results of these measurements show, as in the case of the previous measurement, for a given ion the CCD response increases with energy and for a given particle energy the response decreases with increasing mass of the particle. These results are in agreement with predictions of the theory of the range of ions in solids. The results also show the possibility for the application of the delta doped CCD as a detector for low energy particle measurements for space plasma physics applications.
Semantic networks and associative databases: two approaches to knowledge representation and reasoning

Two models, one originating from an artificial-intelligence paradigm and the other from database research, that incorporate connectionist techniques into their knowledge representation and reasoning processes are described. The first approach, called evidential reasoning, is based on semantic networks and focuses on solving inheritance and recognition queries using a rich internal structure. The second approach, called the associative relational database, provides a query language to manipulate knowledge stored in simple uniform structures. In addition to solving ordinary information retrieval, associative databases support robust retrieval with imprecise queries, which is impossible in traditional databases. The two modeling techniques are compared. >
Pulmonary function evaluation of cats after one year of exposure to diesel exhaust

Adult male, inbred, disease-free cats of uniform age and size were exposed eight hours per day, seven days per week to a 1 : 18 dilution of diesel exhaust emissions. After one year of exposure, the animals were removed from the chambers for measurement of lung volumes, forced expiratory flow rates, dynamic compliance and resistance, diffusing capacity, and nitrogen washout. No important changes in pulmonary function were detected with the exception of a decrease in closing volume (P < 0.05). The inability to detect decrements in pulmonary function may have been due to insufficient cocentration of exhaust, insufficient exposure length, or to the use of a species resistant to diesel exhaust. To test these possibilities, the cats are being exposed for an additional year, and another species, hamsters, are being exposed for future testing at exhaust dilutions of 1 : 18 and 1 : 9.
EVALUATION OF THREE BIOLOGICAL FILTERS SUITABLE FOR AQUACULTURAL APPLICATIONS

A staged rotating biological contactor (RBC), packed tower (PT, trickling filter) and fluidized bed reactor (FBR) were tested simultaneously using common water from a fish culture tank. The culture tank was stocked with channel catfish (Ictalurus punctatus) at three different densities (approximately 227, 113 and 57 kg/m3) to provide solute concentrations in the filter influent similar to those expected under intensive culture practices. Mean concentrations of total ammonia nitrogen (NH4+-N + NH3-N) in the culture tank were 1.46 (3.50-0.42), 1.26 (1.78-0.95) and 0.36 (0.48- 0.28) mg N/liter at the respective stocking densities. The RBC provided the best nitrification efficiencies (74%, 82% and 76%, respectively). The efficiency of the PT (23%, 42% and 51%) was somewhat better than the FBR (8%, 28% and 32%). The rate of ammonia removal across the entire RBC was 0.79, 0.63 and 0.19 g N/m2d-1, with removal across the first two stages of 1.31, 1.15 and 0.31 g N/m2d-1. The PT provided arranonia removal of only 0.25, 0.32 and 0.14 g N/m2d-1. Dissolved oxygen, nitrite, nitrate, pH, alkalinity and chemical oxygen demand analysis was also performed.
Influence of annealing on kinetic trapping parameters in LiF:Mg, Cu, P thermoluminescent phosphors

Three types of LiF:Mg,Cu,P phosphors with different pre-annealing temperatures have been studied using glow curve analysis techniques. The principal dosimetric glow peak near 230°C is confirmed to be composed of two overlapping peaks. Both MCP-N pellets and GR200 chips show significant changes in peak temperature, peak height and trapping parameters after being annealed at temperatures higher than 260°C. Specifically, the activation energy and pre-exponential factor for the principle glow peaks are shown to decrease with increasing annealing temperature. This occurs while the peak height is decreasing and the peak temperature is increasing due to these annealing treatments. Comparing the trapping parameters of these LiF:Mg,Cu,P phosphors with those of single crystal samples confirms the important role played by phosphorus in determining the thermoluminescent sensitivity in these materials.
Mechanisms of foot-and-mouth disease virus tropism inferred from differential tissue gene expression

Foot-and-mouth disease virus (FMDV) targets specific tissues for primary infection, secondary high-titer replication (e.g. foot and mouth where it causes typical vesicular lesions) and long-term persistence at some primary replication sites. Although integrin αVβ6 receptor has been identified as primary FMDV receptors in animals, their tissue distribution alone fails to explain these highly selective tropism-driven events. Thus, other molecular mechanisms must play roles in determining this tissue specificity. We hypothesized that differences in certain biological activities due to differential gene expression determine FMDV tropism and applied whole genome gene expression profiling to identify genes differentially expressed between FMDV-targeted and non-targeted tissues in terms of supporting primary infection, secondary replication including vesicular lesions, and persistence. Using statistical and bioinformatic tools to analyze the differential gene expression, we identified mechanisms that could explain FMDV tissue tropism based on its association with differential expression of integrin αVβ6 heterodimeric receptor (FMDV receptor), fibronectin (ligand of the receptor), IL-1 cytokines, death receptors and the ligands, and multiple genes in the biological pathways involved in extracellular matrix turnover and interferon signaling found in this study. Our results together with reported findings indicate that differences in (1) FMDV receptor availability and accessibility, (2) type I interferon-inducible immune response, and (3) ability to clear virus infected cells via death receptor signaling play roles in determining FMDV tissue tropism and the additional increase of high extracellular matrix turnover induced by FMDV infection, likely via triggering the signaling of highly expressed IL-1 cytokines, play a key role in the pathogenesis of vesicular lesions.
Interprofessional Education Among Student Health Professionals Using Human Patient Simulation

Objective. To describe the planning, implementation, and outcomes of an interprofessional education clinical laboratory facilitated through human patient simulation.Design. An interprofessional education clinical laboratory was developed with a patient-care scenario of acute exacerbation of heart failure that incorporated the use of a high-fidelity patient simulator. Pharmacy and nursing students assumed clinical roles in this realistic scenario and collaborated to diagnose and treat the patient.Assessment. Student attitudes toward and readiness to participate in interprofessional education improved following participation in the laboratory. Students reported that the greatest benefit of the experience was in their communication skills.Conclusion. Students’ ability to participate in interprofessional education experiences and their attitudes toward them improved following participation in this curricular initiative. Further evaluation of the impact of interprofessional education on student learning outcom...
Tipping Point: Biosimilars, Emerging Markets, and Public-Private Engagement to Promote Global Health

Biosimilars, also known as follow on biologics, are complex biotechnology drugs that are similar, but not identical, to original biologic drug forms, and represent potential lower cost versions that may improve access. Yet biologics and their biosimilar forms have a key safety concern: unwanted immunogenicity. Emerging markets have tremendous interest in biosimilars, but are at a tipping point: they are moving from developing country concerns (e.g., communicable disease) to developed country needs (e.g., cancer therapies) that require biologic drugs. Production, however, is at lower than current Good Manufacturing Practice levels standard in highly-regulated markets. Emerging market public-private partnerships between public agencies, local producers, and global pharmaceutical firms, can incentivize biosimilar production at higher quality levels than required for local markets as well as position themselves for entry into developed markets. Public health goals can be reached while increasing economic opportunities in these markets to benefit global health.
Use of Multivariate Analysis to Determine Temperature from Low-Resolution Infrared Spectra of Carbon Dioxide

The remote optical monitoring of gaseous contaminants is important for both military and industrial applications. An important parameter for quantifying chemical species and for predicting plume dynamics is the temperature. While in some industrial monitoring situations it may be practical to independently measure the temperature of stack emissions, for compliance monitoring and military chemical reconnaissance a remote optical means of estimating gas plume temperature is required. It was noticed that the band shape of low-resolution spectra of carbon dioxide in equilibrium with an exhaust plume was very sensitive to temperature. Spectra of carbon dioxide were acquired under controlled laboratory conditions in 5° increments from 20 to 200 °C. Various multivariate models were used to predict the temperature. It was found that partial least-squares (PLS) was unable to effectively model the simultaneous changes in amplitude and bandwidth with temperature. However, principal component regression (PCR) was found to be well correlated with temperature and allowed cross-validated prediction within 4% error.
Estimation Algorithms for Low Pressure Cooled EGR in Spark-Ignition Engines

Low-pressure, Cooled Exhaust Gas Recirculation (LPC EGR) brings significant fuel economy , NOx reduction and knock suppression benefits to a modern, boosted, downsized Spark Ignition (SI) engine. As a prerequisite to design an engine control system for LPC EGR, this paper presents development of a set of estimation algorithms to accurately estimate the flow rate, pressure states and thermal states of the LPC EGR-related components.
Progenitor cell maturation in the developing vertebrate retina

Progenitor cells in the developing retina initially divide so that each division produces two cells that divide again. Subsequently, progenitor cells change their mode of division so that one or both cells produced by a division can withdraw from the mitotic cycle and differentiate. We asked how these two progenitor cell stages differ molecularly and what controls the switch in the mode of division. We show that early preneurogenic progenitor cells express the transcription factor, Sox2, and the Notch ligand, Delta1. More mature neurogenic progenitor cells express Sox2 and the bHLH transcription factor, E2A, and not Delta1. Notch signaling maintains progenitor cells in the preneurogenic state. Sonic hedgehog expressed by newly differentiating cells initiates maturation of progenitor cells from preneurogenic to neurogenic at the neurogenic front, possibly by down-regulating Delta1 expression. Our results show that the preneurogenic-to-neurogenic transition is a highly organized unidirectional step made in unison by neighboring cells. Developmental Dynamics 238:2823–2836, 2009. © 2009 Wiley-Liss, Inc.
Effect of UV light on sister-chromatid exchanges, activation of alternative sites of replicon initiation and thymidine incorporation in CHO AA8, UV61 and UV5 cells

The relative importance of the UV-induced pyrimidine(5-6)pyrimidine and the pyrimidine(6-4)-pyrimidone lesions in sister-chromatid exchanges (SCEs), activation of alternative sites of replicon initiation and thymidine incorporation were examined using wild-type Chinese hamster ovary (CHO) AA8 cells which remove both lesions, mutant CHO UV61 cells which remove only the (6-4) lesion and mutant CHO UV5 cells which remove neither lesion. Our data suggest that both lesions play a role in each end point examined. The relative importance of these lesions is dependent on the end point studied as well as the fluence used. For SCE induction and the activation of alternative sites of replicon initiation, the (6-4) lesion appears to play a predominant role, while for the thymidine incorporation studies the (6-4) lesion appears to play the predominant role at low fluences while the role of the (5-6) lesion increases at higher fluences.
Software test cases: is one ever enough?

In this paper, software testing theory was examined as it pertains to one test at a time. In doing so, the author hopes to highlight some useful facts about testing theory that are somewhat obvious but often overlooked. Some precise statements about how bad the one-test policy can be were also made
Transduction and control of sqeezed light sources by localized and propagating surface plasmons

The transduction of multi-spatial-mode squeezed light sources by localized surface plasmon mediated extraordinary-optical-transmission provides a basis for nanoscale quantum information protocols and quantum enhanced biosensing.
Self-Adaptive Kinematic-Dynamic Model for Overland Flow

AbstractThe authors developed an innovative two-dimensional finite-volume model for overland flow, which is capable of simultaneously applying the kinematic wave approximation and the full Saint-Venant (dynamic) equations to different regions of the modeled domain. A locally based criterion is employed to determine the applicability limits for the kinematic approximation. The model assesses the flow and topography on a cell-by-cell basis at each time step over an unstructured, triangular grid and determines the appropriate solution method for each individual cell. Several case studies are shown that illustrate the adaptive kinematic-dynamic model’s flexibility and robustness. The effects of the user-defined limit for the kinematic wave approximation and the abrupt switch from one solver to another are explored for the adaptive kinematic-dynamic model.
Racial/ethnic differences in preferences for total knee replacement surgery

Abstract Objectives To determine whether there are ethnic differences in preferences for surgery vs. medical treatment of knee osteoarthritis (OA). Study Design and Setting Cross-sectional in-person interviews using conjoint analysis methodology, a technique often used in marketing, involved individuals making choices between alternative hypothetical scenarios for medical or surgical treatment of knee OA. One hundred ninety-three individuals over the age of 20 were recruited through random digit dialing in Harris County, TX, and 198 individuals with knee OA were recruited from a large outpatient health care provider in Houston, TX. Results African Americans were significantly less likely to chose surgery than whites (odds ratio 0.63 [0.42, 0.93]). Women and older individuals were also less likely to choose surgery (0.69 [0.51, 0.94], 0.98 [0.97, 0.99]). Larger reductions in negative symptoms with surgery significantly increased the likelihood of choosing surgery. There was no difference between the public and patients, and no effect of income level. Conclusions Disparities in knee replacement rates among ethnic groups may be partly due to differences in preferences for surgery. Conjoint analysis was shown to be a feasible methodology for collecting preferences in health research. This methodology has great promise in contributing to our knowledge of drivers of health care decision making in individuals.
SAR image processing for moving target focusing

A novel synthetic aperture radar (SAR) image processing technique has been developed to refocus the ground moving target signature from its smeared response in the SAR image of the stationary ground. The technique implements a matched moving target filter that is derived from the signal history along the target range-Doppler migration path mapped onto the SAR image from its real-space trajectory. The spatial filter is specified by both the apparent target range in the image and the magnitude of the relative target-to-radar velocity. Range dependence may also be eliminated in image filtering by performing the inverse Fourier transform of the SAR image data spectrum after a spatial frequency coordinate transformation.
Sociodemographic trends in national ambulatory care visits for hepatitis C virus infection.

Poor and non-white patients are disproportionately infected with the hepatitis C virus (HCV). The objective of this research is to determine sociodemographic patterns of HCV-related ambulatory care visits over time. Data from the National Ambulatory Medical Care Survey (NAMCS) and the National Hospital Ambulatory Medical Care Survey-Outpatient (NHAMCS-OPD) for the years 1997–2005 were analyzed in 3-year intervals. Demographic and other variables were compared for each period, and multivariable logistic regression was performed to examine whether the likelihood of a visit being HCV-related (versus non-HCV) was independently associated with (1) race and/or (2) Medicaid status over time. The total number of HCV-related ambulatory visits more than doubled from 3,583,585 during the years 1997–1999 to 8,027,166 during 2003–2005. During this time, the proportion of non-whites and Medicaid recipients presenting for HCV-related visits approximately doubled (non-whites: 16% vs. 33%, P = 0.04; Medicaid recipients: 10% vs. 25%, P = 0.07). In 2003–2005, HCV-related visits were more than twice as likely to occur among non-white patients vs. white patients (OR = 2.49; 95% CI: 1.60–3.86) and patients on Medicaid vs. non-Medicaid (3.49; 1.79–6.80). Our results show that HCV-associated ambulatory care visits are increasing, with a greater proportion of visits occurring among non-white patients and Medicaid recipients.
Biological Chemistry of Thiols in the Vasculature and in Vascular-related Disease

For all their similarities in structure and common chemistry, the functions of the amino thiols in vascular biology are remarkably different. This review details the basic chemistry of sulfhydryls that dictates their functions in health and disease. In addition, the biochemistry and metabolism of each thiol are outlined, in an effort to highlight its specific contributions to the normal biology and physiology of blood vessels and to the pathogenesis of vascular-related disease.
Spin−Orbit Effects in the Ground States of Singly Positive and Neutral V2, VNb, and Nb2: INDO/S and Empirical Model Calculations

Ground-state spin−orbit splittings in V2+, VNb+, and Nb2+ were investigated with spin−orbit configuration interaction (SOCI) calculations using the intermediate neglect of differential overlap method for optical spectroscopy (INDO/S). Splittings found for the X4Σ- ground states of V2+ and VNb+ using a CI treatment isolating essential correlation of the ground and isoconfigurational a2Σ+ and b2Σ- state wave functions agreed well with experiment. The size of the splitting for Nb2+ was predicted. In all three cases the a2Σ+ and b2Σ- states were found to be strongly coupled by the spin−orbit operator. Several perturbative models for predicting energies of interacting excited states based on measured splittings were analyzed by comparing to SOCI results for V2, VNb, and Nb2. Second-order perturbation theory, treating only the isoconfigurational states, and neglecting overlap and CI in computing couplings was the best choice of approximations due to cancellation of errors. An empirical model treating the isocon...
Electrotransformation of Lactobacillus acidophilus Group A1

Two strains of Lactobacillus acidophilus Group A1, the neotype ATCC 4356 and a human isolate NCFM-N2, widely used as a dietary adjunct in milk and cultured dairy products, were transformed with plasmid DNA by electroporation. The transformation characteristics exhibited by the two L. acidophilus strains were found to differ markedly even though they appeared similar at the genomic level based on the DNA patterns of SmaI restriction fragments. To our knowledge, this is the first report of a consistent, reproducible transformation system of Lactobacillus acidophilus strains comprising the A1 DNA homology group.
Comparative phylogeography as an integrative approach to historical biogeography

Phylogeography has become a powerful approach for elucidating contemporary geographical patterns of evolutionary subdivision within species and species complexes. A recent extension of this approach is the comparison of phylogeographic patterns of multiple co-distributed taxonomic groups, or ‘comparative phylogeography.’ Recent comparative phylogeographic studies have revealed pervasive and previously unrecognized biogeographic patterns which suggest that vicariance has played a more important role in the historical development of modern biotic assemblages than current taxonomy would indicate. Despite the utility of comparative phylogeography for uncovering such ‘cryptic vicariance’, this approach has yet to be embraced by some researchers as a valuable complement to other approaches to historical biogeography. We address here some of the common misconceptions surrounding comparative phylogeography, provide an example of this approach based on the boreal mammal fauna of North America, and argue that together with other approaches, comparative phylogeography can contribute importantly to our understanding of the relationship between earth history and biotic diversification.
MOTION PERCEPTION : HOW ARE MOVING IMAGES SEGMENTED?

Visual images are segmented perceptually by a variety of cues, including color and motion. Recent experiments, using perceptual and neurophysiological approaches, have explored the complex interaction between these attributes. A full account will certainly include the effects of directed attention.
GRETA - Gamma Ray Energy Tracking Array

Gamma ray energy tracking is a new concept for detecting gamma rays. It can be implemented as a 4π array of highly segmented Ge detector, which would advance detection sensitivity by three orders of magnitude in certain applications. Such an array will provide tremendous discovery potential at current stable and exotic beam facilities, as well as at future facilities. The development of a tracking array for nuclear structure physics has brought together scientists from different areas. Technical advances made in the last 5 years have demonstrated that the construction of a gamma ray energy‐tracking array is feasible, and a plan for constructing a US array is in place.
Spontaneous loss of viral episomes accompanying Epstein-Barr virus reactivation in a Burkitt's lymphoma cell line

Life-long viral persistence is a hallmark of human herpesvirus infection. In the Epstein-Barr virus (EBV)-positive Burkitt's lymphoma (BL) cell line, Mutu, spontaneous loss of all viral episomes accompanied productive viral DNA replication. The molecular configuration of intracellular EBV DNA evolved from monoclonal episomes in cells retaining the original tumor phenotype to predominantly replicating linear DNA and, subsequently, only integrated forms in BL cells that had acquired the lymphoblastoid cell phenotype. Transient appearance of deleted, rearranged WZhet EBV DNA capable of disrupting viral latency, along with the integration of viral DNA into human chromosomes, indicates a genetic instability in the host cell which, if duplicated in vivo, may affect configuration and persistence of the viral genome in expanding malignant cell clones.
Ontogenetic variation in the autecology of the greater earless lizard Cophosaurus texanus

We investigated the potential for ontogenetic resource partitioning within a population of the Texas earless lizard Cophosaurus texanus. Results from focal samples, line transects, haphazard observations, and stomach flushes compiled in summer (July 1993) and autumn (September 1995) revealed differences in microhabitat use and diet between adults and juveniles. Juveniles use rock perches more frequently than adult males, and consume smaller prey than adults. No ontogenetic differences in thermal ecology were observed. Diet differences between juveniles and adults may be attributed to the inability of juveniles to handle large prey items. Differences between juveniles and adults in prey size and microhabitat use suggest ontogenetic variation in foraging, predator avoidance, and territory defense.
Environments of physically neglected children

A reanalysis of data from the Gaudin, Polansky, Kilpatrick, and Shilton 1996 study of 185 low-income families combined information from neglectful families with information from the comparison group. Physical neglect was related to maternal depression, more adult problems, stressful life events, negative family affect, and low social support. Multivariate analyses indicated that a combination of higher maternal education, positive family affect, more supportive services, and fewer stressful life events predicted the provision of adequate physical care among low-income families.
Social host liability for minors and underage drunk-driving accidents

Social host laws for minors aim to reduce teenage alcohol consumption by imposing liability on adults who host parties. Parents cite safety reasons as part of their motivation for hosting parties, preferring their teens and their teens' friends to drink in a supervised and safe locale. Both sides predict an effect of social host liability for minors on alcohol-related traffic accident rates for under-aged drinkers; the effects, however, work in opposite directions. This paper finds that, among 18-20 year olds, social host liability for minors reduced the drunk-driving fatality rate by 9%. I find no effect on sober traffic fatalities. Survey data on drinking and drunk driving suggest the declines resulted mostly from reductions in drunk driving and not reductions in drinking.
Reversible Surface Oxidation and Efficient Luminescence Quenching in Semiconductor Single-Wall Carbon Nanotubes

We have investigated reversible single-wall carbon nanotube (SWNT) oxidation by quantitative analysis of the oxide-induced absorption bleaching and luminescence quenching at low pH. These data, in combination with DFT structure calculations, suggest that the nanotube oxide is a 1,4-endoperoxide. At low pH, the endoperoxide protonates to create a hydroperoxide carbocation, introducing a hole in the SWNT valence band. Nanotube luminescence is extremely sensitive to quenching by hole-doping, while the absorption is relatively robust.
Protein synthesis early in the developmental cycle of Chlamydia psittaci.

Abstract The incorporation of [35S]methionine into protein by intracellular and host-free Chlamydia psittaci 6BC was analyzed at intervals between 15 min and 28 h postinfection by autoradiography of sodium dodecyl sulfate-polyacrylamide gels. The profiles of proteins synthesized in the two systems were similar at all times, indicating that the host-free system can be used to monitor the temporal expression of genes in chlamydiae. The host-free system permitted detection of synthesis of chlamydial proteins as early as 15 min postinfection. Some of the proteins synthesized during the initial phases of reorganization of elementary bodies to reticulate bodies either were not synthesized or were synthesized in greatly reduced amounts during the other phases of the developmental cycle. The effects of rifampin and actinomycin D indicated that host-free protein synthesis was at least partially dependent on the initiation and continuation of RNA synthesis in the isolated organisms.
Least likely suicide : the search for my father, Ross Lockridge, Jr., author of Raintree County

"Ross Lockridge, Jr. took his own life on March 6th, 1948, two months following publication of his best-selling novel, Raintree County. The thirty-three year old author from Indiana left his wife and four children. His second son, Larry Lockridge, five years old at that time, has undertaken a search for answers to what has been called the greatest single mystery in American letters. Here, he describes the psychology of survivorship as well as the convergence of factors that led to suicide-personality disorder (narcissistic), biological (possibly genetic) predisposition to depression, and cultural factors related to success in the United States. A merging of such interpretive methods may be more productive than a privileging of one over the other."
Model-integrated design toolset for polymorphous computer-based systems

Polymorphous computer-based systems are systems in which the CPU architecture "morphs" or changes shape to meet the requirements of the application. Optimized and efficient design for these systems requires exploration along axes beyond those of traditional system design. In this paper we outline a model-integrated toolset to aid in the specification, analysis and synthesis of polymorphous applications. Polymorphous systems can be developed utilizing a four-tiered approach, where inherent application properties and characteristics govern design practices at each level. We show through the development of the model-integrated approach that polymorphous system design is inherently coupled with the search and exploration of a combinatorial space of design tradeoffs. Design tools are needed to efficiently evaluate this large and complex space in order to arrive at near-optimal application implementations.