cssi/SciSciGPT-SciSciNet huggingface dataset:
Best practices for infection prevention in penile prosthesis surgery.

Purpose of review In this review, we synthesize the most current data on strategies for the prevention and reduction of infections in men undergoing penile prosthesis surgery. We highlight important strategies for preventing infections along every step from patient selection, to the preoperative, intraoperative and postoperative states. Recent findings Over the last decade, significant advances have been made to help minimize penile implant infections, with the most impactful likely being the introduction of antibiotic coated penile implants. Although this has led to infection rates lower than 0.5% being reported in some series, it appears that more virulent organisms are causing a larger share of infections. Summary The change in the microbiology and persistent occurrence of penile implant infections challenges us to develop strategies to target these organisms by using novel antibiotic mixes for irrigation, dips and implant coatings. Equally important is the continual search to identify patient risk factors for the development of infections and the further optimization of the use of oral and intravenous antibiotics. It is likely we will find inspiration by looking at nonurological surgical specialties where implantation of permanent devices is routine.
Fundamentals of Using Cracked Film Lithography to Pattern Transparent Conductive Metal Grids for Photovoltaics.

The fundamentals of using cracked film lithography (CFL) to fabricate metal grids for transparent contacts in solar cells were studied. The underlying physics of drying-induced cracks were well-pre...
What is Nietzsche’s genealogical critique of morality?

In this paper, I examine the method behind Nietzsche’s genealogical critique. I do not offer a comprehensive characterization and defense of his execution of this critique, but I sometimes allude t...
Study of variation in natural frequencies of bio-composites due to structural damage

The purpose here is to study the variation in the natural frequency of a material due to damage. Also, compare the shift in Natural Frequency that of a SYP-SP (Sweet Potato) bio-composite to a comm...
Referencing the pectoralis major tendon for humeral stem height placement in reverse shoulder arthroplasty for fracture

Abstract Background Proximal humerus fractures remain a challenging problem, and reverse total shoulder arthroplasty (RSA) has demonstrated reliable outcomes in fracture applications. Despite this, guidelines for placement of the humeral component are lacking. Methods Twelve cadaveric shoulders (6 cadaveric torsos) were utilized. An onlay RSA stem was placed with the lateral potion of the humeral cup positioned at the level of the greater tuberosity. Measurements were taken from the top of the pectoralis major tendon to the top of the humeral stem. A separate computer-aided analysis was conducted analyzing the height of an RSA humeral stem and an RSA humeral stem with a cup using values extrapolated from prior data. Results The average distance from the top of the pectoralis to the top of the humeral stem was 4.0 cm (3.4 cm to 4.8 cm) with a standard deviation of 4.1. The humeral cup added an average of 9.1 mm. Computer-aided design data demonstrated the average height of the humeral stem was 3.9 cm above the superior aspect of the pectoralis tendon, and the average height with the humeral cup added was 4.8 cm. Conclusion Both the cadaveric and computer-aided design data demonstrated a similar height for both the distances from the superior portion of the pectoralis to the superior aspect of an onlay RSA stem and the humeral cup. The measurement from the humeral cup may allow for translational use with inlay RSA humeral stems. This study demonstrates the superior border of the pectoralis major tendon to be a reliable landmark in RSA humeral stem placement. Level of evidence Level IV; Cadaveric Study
Rapid Induction of Pulmonary Inflammation, Autoimmune Gene Expression, and Ectopic Lymphoid Neogenesis Following Acute Silica Exposure in Lupus-Prone Mice

Occupational exposure to crystalline silica (cSiO2) is etiologically associated with systemic lupus erythematosus (lupus) and other autoimmune diseases. cSiO2's autoimmune effects in humans can be mimicked chronically in female lupus-prone NZBWF1 mice following repeated exposure to the particle. However, the immediate and short-term effects of cSiO2 in this widely used model of autoimmune disease are not well-understood. In the present study, we tested the hypothesis that a single acute cSiO2 dose triggers early presentation of cellular, histopathological, transcriptomic, and protein biomarkers of inflammation and autoimmunity in lupus-prone mice. Eight-week old female NZBWF1 mice were intranasally instilled once with 2.5 mg cSiO2 or saline vehicle and necropsied at 1, 7, 14, 21, and 28 d post-instillation (PI). Analyses of bronchoalveolar lavage fluid (BALF) and lung tissue revealed that by 7 d PI, acute cSiO2 exposure persistently provoked: (i) robust recruitment of macrophages, neutrophils, and lymphocytes into the alveoli, (ii) cell death as reflected by increased protein, double-stranded DNA, and lactate dehydrogenase activity, (iii) elevated secretion of the cytokines IL-1α, IL-1β, IL-18, TNF-α, IL-6, MCP-1, and B cell activation factor (BAFF), and (iv) upregulation of genes associated with chemokines, proinflammatory cytokines, lymphocyte activation, and type I interferon signaling. The appearance of these endpoints was subsequently followed by the emergence in the lung of organized CD3+ T cells (14 d PI) and CD45R+ B cells (21 d PI) that were indicative of ectopic lymphoid structure (ELS) development. Taken together, acute cSiO2 exposure triggered a rapid onset of autoimmune disease pathogenesis that was heralded in the lung by unresolved inflammation and cell death, proinflammatory cytokine production, chemokine-driven recruitment of leukocytes, an interferon response signature, B and T cell activation, and ELS neogenesis. This short-term murine model provides valuable new insight into potential early mechanisms of cSiO2-induced lupus flaring and, furthermore, offers a rapid venue for evaluating interventions against respirable particle-triggered inflammation and autoimmunity.
Fluid Cognitive Abilities Are Important for Learning and Retention of a New, Explicitly Learned Walking Pattern in Individuals After Stroke

BackgroundThere is significant variability in poststroke locomotor learning that is poorly understood and affects individual responses to rehabilitation interventions. Cognitive abilities relate to...
Monitoring and Detection Time Optimization of Man in the Middle Attacks using Machine Learning

The Internet of Things (IoT) is growing with the advancement of technology. Many vendors are creating IoT devices to leverage the quality of life of consumers. These devices include smart grids, smart homes, smart health care systems, smart transportation, and many other applications. IoT devices interact with the environment and each other using sensors and actuators. However, the widespread proliferation of IoT devices poses many cybersecurity threats. The IoT devices’ interconnection opens the door to attackers who try to gain unauthorized access to these devices. For many IT networks, establishing trust and security during the device operation is challenging. Further, devices also may leak vital information, which is a significant concern in cybersecurity. Prior research has shown that security breaches have increased by 67% over the past five years, and 95% of HTTPs servers are vulnerable to Man-in-the-middle (MIM) attacks. This paper examines attack datasets from the Hacking and Countermeasure Research Lab (HCRL) collected from real-life IoT devices that include smart cameras, laptops, and smartphones [1]. We present a model using Random Forest, Logistic Regression, and Decision Tree. Results indicate that the overall detection accuracy is 98-100%, which is more promising than traditional Intrusion Detection Systems (IDS).
Accurate and Efficient Computation of Gabor Features in Real-Time Applications

Gabor features are widely used in many computer vision applications such as image segmentation and pattern recognition. To extract Gabor features, a set of Gabor filters tuned to several different frequencies and orientations is utilized. The computational complexity of these features, due to their non-orthogonality, prevents their use in many real-time or near real-time tasks. Many research efforts have been made to address the computational complexity of Gabor filters. Most of these techniques utilize the separability of Gabor filters by decomposing them into 1-D Gaussian filter. The main issue in these techniques is the efficient pixel interpolation along the desired direction. Sophisticated interpolation mechanisms minimize the interpolation error with the increased computational complicity. This paper presents a novel framework in computation of Gabor features by utilizing a sophisticated interpolation scheme --- quadratic spline --- without increasing the overall computational complexity of the process. The main contribution of this work is the process of performing the interpolation and the convolution in a single operation. The proposed approach has been used successfully in real-time extraction of Gabor features from video sequence. The experimental results show that the proposed framework improves the accuracy of the Gabor features while reduces the computational complexity.
NEONATAL MYASTHENIA GRAVIS: REPORT OF TWO CASES AND REVIEW OF THE LITERATURE

Two male infants with neonatal myasthenia gravis are described. The serum of one patient and his myasthenic mother had no neuromuscular blocking activity or antinuclear globulin. Striation binding globulin was positive in the serum of the mother, but not the infant. Eighty two collected patients are reviewed. Incidence was 12% of babies born to myasthenic mothers. Onset was within 72 hours of birth. Mean duration was 18 days and maximum was 47 days. Nine patients died, with a mean duration of 6 days and a maximum of 21 days. The remaining patients recovered without recurrence, except for recurrence at 2 years in one patient. Manifestations were feeding difficulty (87%), generalized weakness (69%), respiratory difficulty (65%), feeble cry (60%), and facial weakness (54%), including ptosis (15%). Pharmacologic tests with neostigmine or edrophonium were positive in 86%. Management consisted of anticholinesterase medication in 81% for a mean of 21 days and general care, particularly respiratory care. The mothers all had generalized myasthenia gravis. Four mothers did not receive anticholinesterase medication and nine had undergone thymectomy. Eleven mothers subsequently had a second affected child, and five mothers had a normal child. There was no relation of neonatal myasthenia to striation binding or antinuclear globulin in serum of mother or infant.
What Is End-User Software Engineering and Why Does It Matter?

End-user programming has become ubiquitous, so much so that there are more end-user programmers today than there are professional programmers. End-user programming empowers--but to do what? Make really bad decisions based on really bad programs? Enter software engineering's focus on quality. Considering software quality is necessary, because there is ample evidence that the programs end users create are filled with expensive errors. In this paper, I consider what happens when we add to end-user programming environments considerations of software quality, going beyond the "create a program" aspect of end-user programming. I describe a philosophy to software engineering for end users, and then survey several projects in this area. A basic premise is that end-user software engineering can only succeed to the extent that it respects the fact that the user probably has little expertise or even interest in software engineering.
Acid-soluble nucleotides in human placenta and amniochorionic membrane.

Abstract Acid-soluble nucleotides were extracted from human placenta and amniochorionic membrane using cold 10 per cent trichloroacetic acid. Separation was accomplished by Dowex-1 formate column using gradient elution. Approximately thirteen peaks were identified in both tissues although wide variations in resolution and quantitative measurements were encountered with placental tissue that obviated any comparison between normal and abnormal conditions. There was surprisingly minimal amount of ATP using this method of analysis.
Kinetics of plasma etching silicon with nitrogen trifluoride

A kinetic model, composed of elementary chemical reactions, is derived to predict the etch rate of crystalline silicon with NF3 in a plasma discharge. Experimental data taken from a radial flow plasma etching reactor is used to determine the model’s kinetic parameters. The rate constant for atomic fluorine reacting with silicon was determined to be 1410 cm/min at 25 °C, in good agreement with a value obtained by other investigators.
Nucleation and seismic tremor associated with the glacial earthquakes of Whillans Ice Stream, Antarctica

[1] The ability to monitor transient motion along faults is critical to improving our ability to understand many natural phenomena such as landslides and earthquakes. Here, we usedata from a GPS and seismometer network that were deployed to monitor the regularly repeating glacial earthquakes of Whillans Ice Stream, West Antarctica to show that a unique pattern of precursory slip precedes complete rupture along the bed of the ice stream. Additionally, we show that rupture can be independently tracked by increased levels of microseismic activity, including harmonic tremor, that are coincident with the onset of slip at any location, thus providing a remote means of monitoring stress and rupture propagation during the glacial earthquakes.
Cost-Related Medication Nonadherence and Cost-Saving Behaviors Among Patients With Glaucoma Before and After the Implementation of Medicare Part D

Importance Understanding factors that lead to nonadherence to glaucoma treatment is important to diminish glaucoma-related disability. Objectives To determine whether the implementation of the Medicare Part D prescription drug benefit affected rates of cost-related nonadherence and cost-reduction strategies in Medicare beneficiaries with and without glaucoma and to evaluate associated risk factors for such nonadherence. Design, Setting, and Participants Serial cross-sectional study using 2004 to 2009 Medicare Current Beneficiary Survey data linked with Medicare claims. Coding to extract data started in January 2014 and analyses were performed between September and November of 2014. Participants were all Medicare beneficiaries, including those with a glaucoma-related diagnosis in the year prior to the collection of the survey data, those with a nonglaucomatous ophthalmic diagnosis in the year prior to the collection of the survey data, and those without a recent eye care professional claim. Intervention Effect of the implementation of the Medicare Part D drug benefit. Main Outcomes and Measures The change in cost-related nonadherence and the change in cost-reduction strategies. Results Between 2004 and 2009, the number of Medicare beneficiaries with glaucoma who reported taking smaller doses and skipping doses owing to cost dropped from 9.4% and 8.2% to 2.7% ( P P = .001). However, reports of failure to obtain prescriptions owing to cost did not improve in the same period (3.4% in 2004 and 2.1% in 2009; P = .12). After Part D, patients with glaucoma had a decrease in several cost-reduction strategies, namely price shopping (26.2%-15.2%; P P P Conclusions and Relevance After the implementation of Part D, there was a decrease in the rate that beneficiaries with glaucoma reported engaging in cost-saving measures. Although there was a decline in the rate of several cost-related nonadherence behaviors, patients reporting failure to fill prescriptions owing to cost remained stable. This suggests that efforts to improve cost-related nonadherence should focus both on financial hardship and medical therapy prioritization, particularly in certain high-risk sociodemographic groups.
Tissue loss secondary to extrinsic compression of common iliac artery from uterine leiomyoma: a case report and review of the literature.

Background. Uterine leiomyomas are commonly reported to cause deep venous thrombosis and rarely arterial compression. Case. A 48-year-old woman was transferred to our institution with acute right l...
A Semi Markov-based Analysis of Rate Adaptation Algorithms in Wireless LANs

Rate adaptation plays a key role in determining the performance of wireless LANs. In this paper, we introduce a semi-Markovian framework to analyze the performance of two of the most popular rate adaptation algorithms used in wireless LANs, namely automatic rate fallback (ARF) and adaptive automatic rate fallback (AARF). Given our modeling assumptions, the analysis is exact and provides closed form expressions for the achievable throughput of ARF and AARF. We illustrate the benefit of our analysis by numerically comparing the throughput performance of ARF and AARF in two different channel regimes. The results show that neither of these algorithms consistently outperforms the other. We thus propose and analyze a new variant to AARF, called persistent AARF (or PAARF), and show that it achieves a good compromise between the two algorithms, often performing close to the best algorithm in each of the studied regimes.
Querying streaming point clusters as regions

This paper focuses on one important type of geo-streaming data - point geo-streams. Many interesting applications require selected discrete points with similar observations to be clustered according to spatial proximity and further elevated into higher-level spatial regions. Querying streaming point clusters as regions directly in a geo-stream database has many benefits, but is also very challenging. We propose two query optimization strategies, namely semantics-based optimization and incremental optimization for answering queries involving both point geo-streams and static data set. The experimental results on a streaming meteorological data set demonstrate the effectiveness and the efficiency of the query processing techniques. Compared with the baseline methods, our optimization methods can reduce the total execution time by more than an order of magnitude.
Cell Entry-Associated Conformational Changes in Reovirus Particles Are Controlled by Host Protease Activity

Membrane penetration by reovirus requires successive formation of two cell entry intermediates, infectious subvirion particles (ISVPs) and ISVP*s. In vitro incubation of reovirus virions with high concentration of chymotrypsin (CHT) results in partial digestion of the viral outer capsid to form ISVPs. When virions are instead digested with low concentrations of chymotrypsin, the outer capsid is completely proteolyzed to form cores. We investigated the basis for the inverse relationship between CHT activity and protease susceptibility of the reovirus outer capsid. We report that core formation following low-concentration CHT digestion proceeds via formation of particles that contain a protease-sensitive form of the μ1C protein, a characteristic of ISVP*s. In addition, we found that both biochemical features and viral genetic requirements for ISVP* formation and core formation following low-concentration CHT digestion are identical, suggesting that core formation proceeds via a particle resembling ISVP*s. Furthermore, we determined that intermediates generated following low-concentration CHT digestion are distinct from ISVPs and convert to ISVP*-like particles much more readily than ISVPs. These results suggest that the activity of host proteases used to generate ISVPs can influence the efficiency with which the next step in reovirus cell entry, namely, ISVP-to-ISVP* conversion, occurs.
Thymic Stromal Lymphopoietin-Mediated Extramedullary Hematopoiesis Promotes Allergic Inflammation

Extramedullary hematopoiesis (EMH) refers to the differentiation of hematopoietic stem cells (HSCs) into effector cells that occurs in compartments outside of the bone marrow. Previous studies linked pattern-recognition receptor (PRR)-expressing HSCs, EMH, and immune responses to microbial stimuli. However, whether EMH operates in broader immune contexts remains unknown. Here, we demonstrate a previously unrecognized role for thymic stromal lymphopoietin (TSLP) in promoting the population expansion of progenitor cells in the periphery and identify that TSLP-elicited progenitors differentiated into effector cells including macrophages, dendritic cells, and granulocytes and that these cells contributed to type 2 cytokine responses. The frequency of circulating progenitor cells was also increased in allergic patients with a gain-of-function polymorphism in TSLP, suggesting the TSLP-EMH pathway might operate in human disease. These data identify that TSLP-induced EMH contributes to the development of allergic inflammation and indicate that EMH is a conserved mechanism of innate immunity.
Futile redox cycling: Implications for oxygen radical toxicity

The reduction and the potential autoxidation of quinoid compounds may be viewed as taking place in three cell compartments. In microsomal fractions (endoplasmic reticulum) one-electron reduction by NAPDH-cytochrome P450 reductase leads to the formation of semiquinones which rapidly react with oxygen to form the parent quinone and superoxide anions. The formation of superoxide through this futile cycle leads ultimately to other damaging species (H2O2 and .OH). A similar futile cycle in mitochondria involves NADH dehydrogenase. In this instance, mitochondria initiation of such a cycle with quinones results not only in the formation of toxic radical species but also in the diversion of electrons from phosphorylating pathways. The consequent diminution of cellular ATP may have as important a consequence with respect to the toxicity of quinones as the generation of radicals. Finally, cytosolic DT diaphorase, which carries out a two-electron reduction of quinones to more stable hydroquinones, may compete with the one-electron systems and participate in the detoxification of quinones by supplying hydroquinones for conjugation reactions. The extent of quinone-induced damage may thus vary from cell to cell depending on the integration of these pathways.
Codling Moth: Male Moth Activity in Response to Pheromone Lures and Pheromone-Baited Traps at Different Elevations Within and Between Trees

To characterize the behavior of codling moth, Cydia pomonella (L.), males to sex pheromone sources, we determined the lapsed time for response, number responding, and number of attempted pseudocopulations directed to pheromone placed at various heights in or near apple trees. The time for and number of responses was similar at any height as long as the pheromone source was within and not outside the tree's canopy. Responses to pheromone and captures of moths were significantly lower for pheromone sources or traps outside the tree canopy, whether above, below or between trees. The maximum numerical response was at the 3.0-m level, 1.0–1.5 m from the top of the tree. In an unsprayed apple orchard, the number of moths caught in traps at 3.5 m was not significantly different from the number caught at 1.5 m, but in a sprayed orchard, the number caught at 3.5 m was significantly higher than at 1.5 m in six of 10 biweekly comparisons. Efficiency of low traps (1.5 m) relative to high traps depended on the position of the low trap in relation to the canopy. The canopy effect was larger than the height effect.
Cytological and Immunocytochemical Approaches to the Study of Corneal Endothelial Wound Repair

The vertebrate corneal endothelium represents a unique model system for investigating many cellular aspects of wound repair within an organized tissue in situ. The tissue exists as a cell monolayer that resides upon its own natural basement membrane that can be prepared as a flat mount to observe the entire cell population. Thus, it readily avails itself to many cytological and immunocytochemical methods at both the light microscopic and ultrastructural levels. In addition, the tissue is easily explanted into organ culture where further investigations can be carried out. These techniques have enabled investigators to use many approaches to explore function and changes in response to injury. In vivo, the endothelium acts as a transport tissue to actively pump Na+ and bicarbonate ions from the corneal stroma into the aqueous humor to control corneal transparency. Physiological findings indicate that fluid diffuses back into the stroma, across the endothelium, and thus hydration is said to be controlled by a pump-leak mechanism. Ultrastructural investigations, some employing horseradish peroxidase and lanthanum, have established the morphological basis for this mechanism as apical focal junctions that are not the classical tight junctions and do not constitute a complete zona occludens. Along with these apical focal junctions are gap junctions that appear identical to their counterparts in other cell types. Cytochemical studies localized both Na+K(+)-ATPase and carbonic anhydrase, the main pump enzymes associated with corneal hydration, to the lateral plasma membranes. Corneal endothelial cells of noninjured tissue do not traverse the cell cycle and are considered to be in the "Go" phase of the cell cycle as determined by microfluorometric analysis with DNA binding dyes such as auramin O and pararosaniline-Feulgen. However, injury can initiate cell cycle transverse and histochemical and cytological methods have been used to understand the tissue's response. Classical histochemical studies revealed that increased staining was observed for metabolic (NADase and NADPase) and lysosomal enzymes in cells bordering the wound area. The use of radiolabelled agents has further lead to an understanding of the endothelial wound response. Autoradiographic analyses of 3H-actinomycin D incorporation indicated that injury initiates changes in chromatin leading to increased binding levels of the drug in cells surrounding the wound. This change suggests that those cells undergo heightened macromolecular synthesis and this was confirmed by examining 3H-uridine and 3H-thymidine incorporation. The major mechanism involved in corneal endothelial repair is cell migration. Cytochemical and immunocytochemical investigations have allowed investigators an opportunity to gain some insight into changes that occur during this cellular process.(ABSTRACT TRUNCATED AT 400 WORDS)
Societal stress, political instability, and levels of military effort:

Some countries direct more of their resources to the military than do others. But the question as to why this is so has yet to be answered satisfactorily in a systematic, empirical fashion.' A comprehensive theory explaining the variation in levels of military effort will ultimately have to include both domestic and foreign determinants, for national security policy, of which the size of a country's military effort is an integral part, is the product of an interplay among both domestic and foreign sources (see Huntington, 1961). This article reports some of the domestic findings of a broader study which attempts to construct such a theory (Terrell, 1968). The cost of this strategy of reporting solely domestic findings is that only one aspect of the question of military effort is presented here. One must keep in mind, therefore, that other domestic factors as well as foreign ones may also have an impact on these levels. The advantage of the strategy, however, warrants such an approach, for it will allow concentration on a select set of domestic variables from a perspective that differs markedly from other crossnational comparative studies that look at civil violence and national coercive levels (Feierabend and Feierabend, 1966; Feierabend, Nesvold, with Feierabend, 1970; Gurr, 1968a;
Theory-based predictors of influenza vaccination among pregnant women

Abstract Background Guidelines recommend influenza vaccination for pregnant women, but vaccine uptake in this population is far below the goal set by Healthy People 2020. The purpose of this study was to examine predictors of seasonal influenza vaccination among pregnant women. Methods Between 2009 and 2012, the Vaccines and Medications in Pregnancy Surveillance System (VAMPSS) conducted a prospective cohort study of influenza vaccine safety among pregnant women in the US and Canada that oversampled vaccinated women. Data for the present paper are from an additional cross-sectional telephone survey completed during the 2010–2011 influenza season. We examined predictors of influenza vaccination, focusing on Health Belief Model (HBM) constructs. Results We surveyed 199 pregnant women, 81% of whom had received a seasonal influenza vaccine. Vaccination was more common among women who felt more susceptible to influenza (OR = 1.82, 95% CI 1.10–3.01), who perceived greater vaccine effectiveness (OR = 3.92, 95% CI 1.48–10.43), and whose doctors recommended they have flu shots (OR = 3.06, 95% CI 1.27–7.38). Those who perceived greater barriers of influenza vaccination had lower odds of vaccination (OR = 0.19, 95% CI 0.05–0.75). Perceived social norms, anticipated inaction regret, and worry also predicted uptake, though demographic characteristics of respondents did not. Conclusion The HBM provides a valuable framework for exploring influenza vaccination among pregnant women. Our results suggest several potential areas of intervention to improve vaccination rates.
Pharmacokinetics of ethynyl estradiol: A current view

There are large discrepancies in the values reported for the parameters of ethynyl estradiol pharmacokinetics. Economies in sampling frequency (in the hope that computer simulation will serve the purpose), difficulties in measurement of plasma levels resulting from the small doses used, extensive oxidative metabolism, distribution, and enterohepatic circulation all complicate the effort to obtain reliable data. The problems in quantitating various pharmacokinetic parameters and the techniques for their evaluation, as well as methods for the determination of the requisite sampling times and frequencies are discussed, and best estimates for the various parameters, as derived from the literature, are provided.
Melting of a repulsive screened Coulomb system in two dimensions: Effect of corrugation.

By use of constant energy molecular dynamics simulations, we have investigated the melting and freezing transitions in a two-dimensional system consisting of a constant density of classical particles interacting with a repulsive screened Coulomb (Yukawa) potential. In particular, we have investigated the role of an incommensurate substrate corrugation potential of sixfold symmetry on these transitions by probing the temperature dependence of the bond orientational order parameter (${\mathrm{\ensuremath{\psi}}}_{6}$) and the corresponding susceptibility (${\mathrm{\ensuremath{\chi}}}_{6}$). Other physical quantities such as energy, diffusion constant, and the density of local topological defects have been monitored through the transition region. In the absence of a corrugation potential the system shows a sharp melting transition. In the presence of a corrugation potential the transition temperature increases and the transition becomes smoother. In contrast to the corrugation-free case we find a broad peak in ${\mathrm{\ensuremath{\chi}}}_{6}$ above the transition temperature. We interpret this behavior in terms of the melting of a domain-wall solid. The detailed nature of this smooth transition depends on the degree of incommensurability. Relevance of these results to stage-2 graphite intercalation compounds is discussed.
Regular Examinations for Toxic Maculopathy in Long-term Chloroquine or Hydroxychloroquine Users

Importance According to evidence-based, expert recommendations, long-term users of chloroquine or hydroxychloroquine sulfate should undergo regular visits to eye care providers and diagnostic testing to check for maculopathy. Objective To determine whether patients with rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) taking chloroquine or hydroxychloroquine are regularly visiting eye care providers and being screened for maculopathy. Design, Setting, and Participants Patients with RA or SLE who were continuously enrolled in a particular managed care network for at least 5 years between January 1, 2001, and December 31, 2011, were studied. Patients’ amount of chloroquine or hydroxychloroquine use in the 5 years since the initial RA or SLE diagnosis was calculated, along with their number of eye care visits and diagnostic tests for maculopathy. Those at high risk for maculopathy were identified. Logistic regression was performed to assess potential factors associated with regular eye care visits (annual visits in ≥3 of 5 years) among chloroquine or hydroxychloroquine users, including those at highest risk for maculopathy. Main Outcomes and Measures Among chloroquine or hydroxychloroquine users and those at high risk for toxic maculopathy, the proportions with regular eye care visits and diagnostic testing, as well as the likelihood of regular eye care visits. Results Among 18 051 beneficiaries with RA or SLE, 6339 (35.1%) had at least 1 record of chloroquine or hydroxychloroquine use, and 1409 (7.8%) had used chloroquine or hydroxychloroquine for at least 4 years. Among those at high risk for maculopathy, 27.9% lacked regular eye care visits, 6.1% had no visits to eye care providers, and 34.5% had no diagnostic testing for maculopathy during the 5-year period. Among high-risk patients, each additional month of chloroquine or hydroxychloroquine use was associated with a 2.0% increased likelihood of regular eye care (adjusted odds ratio, 1.02; 95% CI, 1.01-1.03). High-risk patients whose SLE or RA was managed by rheumatologists had a 77.4% increased likelihood of regular eye care (adjusted odds ratio, 1.77; 95% CI, 1.27-2.47) relative to other patients. Conclusions and Relevance In this insured population, many patients at high risk for maculopathy associated with the use of chloroquine or hydroxychloroquine are not undergoing routine monitoring for this serious adverse effect. Future studies should explore factors contributing to suboptimal adherence to expert guidelines and the potential effect on patients’ vision-related outcomes.
Caspases, apoptosis and aging

Caspases are a group of cysteine dependent aspartate-specific proteases. Originally found as the homolog of Ced-3 in C. elegans, 14 caspases have now been identified in mammals to date. Caspases play important roles in both the intrinsic and extrinsic apoptotic pathways and interact with the non-caspase apoptotic pathways. A number of recent published observations have suggested a strong association between apoptosis, age-related diseases and aging. Findings from our group and others reveal a strong correlation between alterations in caspase activity and aging. In this view point, we summarize current knowledge of the connection between caspases and aging observed in a variety of model systems from cultured cells in vitro to the in vivo models of rodents and humans.
Teaching and Learning in a Virtual World.

Although virtual worlds offer teachers the potential to enhance the K-12 curriculum in novel ways, there have been few systematic attempts to instruct teachers about virtual worlds, research their ...
Re-Gaining the Student's Perspective in the Classroom: A Sabbatical Adventure

After spending six years as a tenure-track faculty member and ultimately gaining tenure and promotion at my home institution of California State University, San Marcos (CSUSM), I was set to begin my first sabbatical in fall, 2002. As is no doubt true of many sabbaticals, one of the great successes of my semester-long break from teaching was a renewed interest in the classroom. “Renewal” is frequently identified as one of the primary purposes of a sabbatical; Good ( 1992 , B3), after all, wrote that he became “surprisingly nostalgic for the company of students once the initial shock of being on leave ha[d] worn off.” But my renewed excitement for teaching came largely from once again entering the classroom as a student. Given my own experiences in returning to student life, I enthusiastically encourage faculty colleagues to take occasional opportunities to step away from the instructor's podium and enjoy a class as a member of the student body: not only did I have the opportunity to expand my perspective on interesting subject matter, but re-experiencing life from the student point of view reminded me of why I began teaching in the first place and reinforced important aspects of good teaching practices. [Editor's note: This manuscript was accepted for publication by PS: Political Science and Politics in September, 2004.]
Lattice Boltzmann Study of Bubble Dynamics

The purpose of this work is to assess the applicability of a new two-phase immiscible lattice Boltzmann method based on phase-field method to single bubble dynamics over a wide range of flow regimes. In two-dimensional domain, the bubble geometry, the interface deformation, and the bubble rise characteristics, such as terminal velocity, drag coefficient, and wake properties, are investigated and quantified using dimensionless parameters. These results are further verified by three-dimensional simulations. The results show an excellent agreement with those of the experimental studies and the level-set and volume-of-fluid numerical approaches.
Fast tissue segmentation based on a 4D feature map in characterization of intracranial lesions.

The aim of this work was to develop a fast and accurate method for tissue segmentation in magnetic resonance imaging (MRI) based on a four-dimensional (4D) feature map and compare it with that derived from a 3D feature map. High-resolution MRI was performed in 5 normal individuals, in 12 patients with brain multiple sclerosis (MS), and 9 patients with malignant brain tumors. Three inputs (proton-density, T2-weighted fast spin-echo, and T1-weighted spin-echo MR images) were routinely utilized. As a fourth input, either magnetization transfer MRT was used or T1-weighted post-contrast MRI (in patients only). A modified k-nearest neighbor segmentation algorithm was optimized for maximum computation speed and high-quality segmentation. In that regard, we a) discarded the redundant seed points; b) discarded the points within 0.5 standard deviation from the cluster center that were non-overlapping with other tissue; and c) removed outlying seed points outside 5 times the standard deviation from the cluster center of each tissue class. After segmentation, a stack of color-coded segmented images was created. Our new technique utilizing all four MRI inputs provided better segmentation than that based on three inputs (P < 0.001 for MS and P < 0.001 for tumors). The tissues were smoother due to the reduction of statistical noise, and the delineation of the tissues became sharper. Details that were previously blurred or invisible now became apparent. In normal persons a detailed depiction of deep gray matter nuclei was obtained. In malignant tumors, up to five abnormal tissue types were identified: 1) solid tumor core, 2) cyst, 3) edema in white matter 4) edema in gray matter, and 5) necrosis. Delineation of MS plaque in different stages of demyelination became much sharper. In conclusion, the proposed methodology warrants further development and clinical evaluation. J. Magn. Reson. Imaging 1999;9:768–776. © 1999 Wiley-Liss, Inc.
Life History of Eudiplogaster Aphodii (Rhabditida: Diplogasteridae), a Facultative Parasite of Aphodius Fimetarius (Coleoptera: Scarabaeidae)

The life history of Eudiplogaster aphodii (Bovien) (Rhabditida: Diplogasteridae), a facultative parasite of Aphodius fimetarius (L.) (Coleoptera: Scarabaeidae) was investigated. Third stage infective juveniles of E, aphodii enter the mouth of second and third stage beetle larvae. After penetrating through the host's midgut, the nematodes begin developing in the hemocoel. The nematodes continue to grow as they are carried through the pupa and into the adult stage uf the host. At the time of emergence, when the hosts are ovipositing in dung, the nematodes have approximately doubled in length and width. After leaving the adult beetles, the nematodes molt, mate, and reproduce in the dung. As the substrate begins to dry, third stage infective juveniles are formed. Adult nematodes arising from juveniles taken from beetle hosts possess short tails, whereas second generation adults arising from juveniles taken from agar plates have long filiform tails. This morphological variation in E. aphodii, together with its ability to enter healthy beetle larvae, are unusual characteristics of this nematode.
Ultrastructure of meiosis in Dasya baillouviana (Rhodophyta). II: Prometaphase I-telophase II and post-division nuclear behavior

This is the second of two papers which together are the first comprehensive ultrastructural report of meiosis in a red alga. Many details of the meiotic process in Dasya baillouviana (Gmelin) Montagne are the same as those reported previously for mitotic cells in ceramialian red algae, but several characteristics seem unique to meiotic cells. The nucleus and nucleolus of meiotic cells are larger than those of mitotic cells and large accumulations of smooth ER are often found at the division poles during meiosis 1. The function of the ER accumulations is unknown. Importantly, both interkinesis and a simultaneous division of two separate nuclei during meiosis II was demonstrated. These new observations fail to support earlier speculation on higher red algae for a “uninuclear” meiosis (both nuclear divisions within the same nuclear envelope). However, following meiosis II the four nuclei migrate centripetally and possibly fuse in the center of the tetrasporangium. This post-division nuclear maneuvering is not understood, but our interpretation accounts for the earlier and erroneous impression of “uninuclear” meiosis. Perhaps the most important aspect of meiosis observed in Dasya is its basic adherence to the pattern commonly seen in higher plants and animals. This conservatism of the meiotic process lends further skepticism to the belief that red algae are extremely “primitive” organisms, although they undoubtedly represent a very “ancient” group of eukaryotic plants.
The contribution of gustatory nerve input to oral motor behavior and intake-based preference. I. Effects of chorda tympani or glossopharyngeal nerve section in the rat.

Two-bottle preference and taste-elicited oral motor responses were examined to determine whether the total lingual gustatory denervation that results from combined bilateral chorda tympani (CTX) and glossopharyngeal nerve section (GPX) would (a) alter the ingestive behavior of the rat and (b) if altered, whether the pattern of deficit revealed would be similar to or different from that obtained by sectioning each of the individual nerves separately. Remarkably, intake-based preference was unaffected by an∼80% reduction in taste receptors. Lingual gustatory denervation failed to affect the preference for any of the normally-preferred stimuli. Preference for only two of the 8 normally-avoided solutions was increased following the combined nerve cuts. In contrast, examination of oral motor taste-reactivity responses revealed that combined nerve sections significantly reduced the number of ingestive responses elicited by 5 of 6 normally-preferred and 5 of 8 normally-avoided stimuli. In addition, the pattern of deficits in taste-elicited oral motor responses resulting from the combined section was different from that predicted by summing the effects of the individual nerve sections. We had shown that CTX did not alter aversive behavior to quinine whereas GPX did reduce these responses but did not affect their concentration dependence. Neither CTX nor GPX affected oral motor responses elicited by sucrose. Combined nerve section, by contrast, completely eliminated the concentration-dependent increases in aversive responses to quinine and ingestive responses to sucrose and glycine. In fact, CTX + GPX profoundly reduced the oral motor behavior elicited by all of the chemical stimuli examined. Despite the changes in the pattern of taste-elicited oral motor behavior combined nerve section did not alter (a) the morphology or duration of individual responses, (b) the concentration-dependent increase in aversive responses elicited by MgCl2, or (c) the potentiation in oral motor responses to water seen in water-deprived rats (Expt. 2).
Deterministic adaptive control with slowly varying parameters: an averaging analysis

In this work averaging methods are used to analyse the behaviour of an adaptive controller with slowly varying parameters. The incorporation of time varying parameters into a stability analysis of an adaptive controller leads to certain perturbation terms in the error system. The type of averaging results so far applied to adaptive control cannot deal with these perturbations. Thus, some new averaging theorems are needed. These results are known in the averaging literature. However, here a very simple proof technique has been found which gives finite and infinite interval averaging results under weaker conditions. The averaging analysis shows that, with regard to parameter tracking, the adaptive algorithm behaves like a first-order filter. It is also clear that successful tracking then requires knowledge of the true speed of parameter change.
Modeling of electronic transport in scanning tunneling microscope tip-carbon nanotube systems

A model is proposed for two observed current–voltage (I–V) patterns in a recent experiment with a scanning tunneling microscope tip and a carbon nanotube [Collins et al., Science 278, 100 (1997)]. We claim that there are two mechanical contact modes for a tip (metal)–nanotube (semiconductor) junction (1) with or (2) without a tiny vacuum gap (0.1–0.2 nm). With the tip grounded, the tunneling case in (1) would produce large dI/dV with V>0, small dI/dV with V<0, and I=0 near V=0 for an either n or p nanotube; the Schottky mechanism in (2) would result in I≠0 only with V<0 for an n nanotube, and the bias polarities would be reversed for a p nanotube. The two observed I–V patterns are thus entirely explained by a tip–nanotube contact of the two types, where the nanotube must be n-type.
An examination of methods for the measurements of reactive gaseous mercury in the atmosphere.

Reactive gaseous Hg (RGHg), usually assumed to be HgCl2, may dominate the total Hg depositional flux due to its higher surface reactivity and water solubility. Three methods are currently used for ...
Opting out of social security

Abstract The liability facing a pay-as-you-go social security system can be calculated in several ways. Many conversions, including that which took place in Chile, and in many plans to convert the U.S. system, assume the largest measure, known as the ‘shutdown liability.’ This measure pays many workers who have contributed to the public system more money than the public system is actually worth to them, thereby placing a larger burden on future generations. But other liability measures are hard to implement due to an information asymmetry between the government and individuals about an individual’s skill level. This paper demonstrates that a very simple reform plan—simply letting people opt out of social security—generates a truthful revelation equilibrium in which agents reveal private information about their skill levels. The new assumed liability measure is much smaller since it more accurately assigns a liability to each individual. A smaller liability, therefore, is passed onto future generations, which also generates quicker transition paths. It also does a better job protecting the welfare of the initial elderly when general revenue is used to pay for the transition. Simulation evidence is provided using a large-scale lifecycle model with heterogeneous skill levels.