cssi/SciSciGPT-SciSciNet huggingface dataset:
Estimation of impact forces during multi-point collisions involving small deformations

Collision between hard objects causes abrupt changes in the velocities of the system, which are characterized by very large contact forces over very small time durations. A common approach in the analysis of such collisions is to describe the system velocities using an impulse–momentum based relationship. The time duration of impact and the deformations at the contact points are usually assumed to be negligible for such an impact models, and the system velocities are evolved in terms of the impulses on the system. This type of impact models are usually relevant for hard (rigid) impacts, where deformations at the contact points can be considered negligible. However, these models cannot determine the forces during the impact process. The main objective of this work is to reformulate the impulse–momentum based model to determine the forces during an impact event, by relaxing the rigidity assumption to allow small deformations at the contact points.
Abstract 15842: Body Mass Index in Covid-19: An Independent Risk Factor for Severe Infections

Introduction: The coronavirus disease 2019 (COVID-19) led to a global pandemic. Comorbidities such as hypertension, diabetes mellitus, elevated cholesterol, cardiac/pulmonary diseases, and obesity ...
Urban versus Rural Lawnmower Injuries in Children: A National 13-Year Study

Purpose: Although the AAOS established updated lawnmower safety guidelines in 2014 and POSNA is currently collaborating with the AAP regarding lawnmower injury prevention awareness, a significant number of injuries continue to occur. We sought to elaborate upon the epidemiology of lawnmower injuries in the pediatric age group as well as compare urban vs. rural injuries. Methods: The PHIS (Pediatric Health Information System) database was queried for patients of 1-18 years of age from 2005-2017 who presented to any of the 49 participating hospitals for a lawnmower injury. The patient cohort was identified using a search …
Bilateral Calculi in a Child With Bilateral Single System Ureteroceles

Ureteroceles in children are detected with prenatal sonography and less commonly during the evaluation following a urinary tract infection. Rarely do ureteroceles in the pediatric population present with stones, particularly in a bilateral fashion. We present a case of a 5-year-old boy found to have bilateral intravesical single system ureteroceles harboring multiple large calculi treated successfully with a staged endoscopic approach.
Crawford's Aftershock: Aligning the Regulation of Non-Testimonial Hearsay with the History and Purposes of the Confrontation Clause

Through Crawford v. Washington and its progeny, the United States Supreme Court has limited the reach of the Confrontation Clause to testimonial hearsay. Testimonial hearsay, the court reasoned, was the primary object of the clause. Other commentators have highlighted the history that persuasively shows that banning testimonial hearsay was the chief motivation behind the Confrontation Clause. But what do the purposes and history of the clause have to say about the admission of non-testimonial hearsay statements? Part I examines common law near the Founding, and argues that non-testimonial hearsay was one of the ills that the Confrontation Clause was designed to protect against. Part I additionally proposes a two-tiered approach to interpreting the clause, in which testimonial statements receive the most vigorous form of constitutional scrutiny, but non-testimonial statements receive meaningful scrutiny as well. Part II of the paper then explores what confrontation should mean, both historically and practically, in the context of non-testimonial hearsay. After marshaling relevant caselaw, historical texts, jury instructions and practitioners' guides, Part II additionally concludes that simply re-implementing the old pre-Crawford regime would not adequately or faithfully result in the type of meaningful confrontation demanded by the clause. Part III then proposes four interpretive reforms that would bring American courts closer to harmonizing the Confrontation Clause's regulation with the provision's full range of historical and practical values.
Abstract 15778: The Impact of Health Insurance Status on Heart Transplant Recipients

Introduction: Gaps in insurance coverage have been associated with diminished access to health care for children with chronic illness. Continuity of coverage is associated with improved long-term c...
Interferon maintenance for prevention of relapse in favorable risk AML

Despite significant recent advances in treatment, acute myeloid leukemia (AML) remains a deadly disease in adults, with a five-year survival in the United States of approximately 30% (from 2011 to ...
Optimization of a Pyrimidinone Series for Selective Inhibition of Ca2+/Calmodulin-Stimulated Adenylyl Cyclase 1 Activity for the Treatment of Chronic Pain

Adenylyl cyclase type 1 is an emerging target for the treatment of chronic pain that is downstream on the analgesic pathway from the traditional µ-opioid receptor. AC1 is expressed in the central nervous system and critical for signaling in pain sensitization. Behavioral studies have revealed AC1 knockout mice exhibit reduced behavioral pain sensitization responses similar to morphine administration. AC1, and a closely related isoform AC8, are also implicated to have a role in learning and memory signaling processes. However, reports suggest selectively targeting AC1 over AC8 may be a viable strategy to eliminate potential deleterious effects on learning and memory. Our team has carried out cellular screening for inhibitors of AC1 that yielded a pyrazolyl-pyrimidinone scaffold with potency comparable to previously published AC1 inhibitors, selectivity versus AC8, and improved drug-like physicochemical properties. Structure-activity relationship (SAR) studies produced 36 analogs that balanced improvements in potency with cellular IC50 values as low as 0.25 µM and selectivity versus AC8. Prioritized analogs were selective for AC1 compared to other AC isoforms and other common neurological targets. A representative analog was assessed for efficacy in a mouse model of inflammatory pain and displayed modest anti-allodynic effects. This series of compounds represents the most potent and selective inhibitors of Ca2+/Calmodulin-stimulated AC1 activity to date with reduced off-target liabilities and improved drug-like physicochemical properties making them promising lead compounds for the treatment of inflammatory pain.
Adolescents' Receipt of Sex Education in a Nationally Representative Sample, 2011-2019.

PURPOSE Updated estimates of adolescents' receipt of sex education are needed to monitor trends and potential inequities. METHODS Using nationally representative data from the 2011-2015 and 2015-2019 National Survey of Family Growth, we use logistic regression to examine changes in the receipt of formal sex education by gender. For 2015-2019, we estimate patterns by gender and race/ethnicity for content, timing, and location of instruction. RESULTS Between 2011-2015 and 2015-2019, there were few significant changes in adolescents' receipt of formal sex education. Between these periods, instruction on waiting until marriage to have sex declined (73%-67% female [F.], p = .005; 70%-58% males [M.], p < .001). In both the periods, about half of the adolescents received sex education that meets the minimum standard articulated in national goals. In 2015-2019, there were significant gender differences in the instruction about waiting until marriage to have sex (67% F., 58% M., p < 001) and condom skills (55% F., 60% M., p = .003). Non-Hispanic Black and Hispanic males were less likely than non-Hispanic White males to receive formal instruction before the first sex on sexually transmitted infection/HIV, birth control, or where to get birth control. Many adolescents reported religious settings as the sources of instruction about waiting until marriage to have sex (56% F. and 49% M.), but almost none received instruction about birth control from those settings. CONCLUSIONS Differences in the receipt of sex education, by gender, race/ethnicity, and the location of instruction, leave many adolescents without critical information. Gaps in meeting national objectives indicate the need to expand the provision of sex education.
Acetate Production by Methanogenic Bacteria

Methanosarcina barkeri MS and 227 and Methanosarcina mazei S-6 produced acetate when grown on H2-CO2, methanol, or trimethylamine. Marked differences in acetate production by the two bacterial species were found, even though methane and cell yields were nearly the same. M. barkeri produced 30 to 75 μmol of acetate per mmol of CH4 formed, but M. mazei produced only 8 to 9 μmol of acetate per mmol of CH4.
Resource coordination and transaction costs: A framework for analyzing the firm/market boundary

We develop a framework to classify transaction costs. Our framework is based on the recognition that the types of transaction costs encountered in organizing production vary across the factors of production and over the stages of the production. Our framework allows us to distinguish between the transaction costs of using the market and those of using the firm. Most importantly, it enables us to see that transaction costs are a function of what factors an individual supplies to the production process. This insight, by illuminating the interdependence of transaction costs, contributes towards understanding the firm/market boundary.
Female Managers and the Gender-Based Gap in Education: Evidence from Firm-Level Data in Developing Countries

A number of studies have analyzed differences in males and females in labor market participation rates and the level of wages. Some of these gender-based differences have also been linked to differences in the level of education between males and females. The present paper contributes to this literature by analyzing the relationship between the proclivity of a firm having a female top manager and the level of education among female relative to males in the country. Using firm-level data for 65 developing countries, we find strong evidence that countries with high female enrollment rates in primary, secondary and tertiary education relative to males have a significantly higher proportion of female managers. We also find that the positive relationship between education among females relative to males and the proportion of female managers is much stronger in countries with poor quality of democracy and in countries with no laws mandating the provision of child care. That is, increasing education among females substitute for poor quality of democracy and the lack provision of child care laws with regards to expanding the proportion of females in managerial positions in the country.
A Lightweight Formal Analysis of a Multicast Key Management Scheme

This paper describes the analysis of Pull-Based Asynchronous Rekeying Framework (ARF), a recently proposed solution to the scalable group key management problem in secure multicast. A model of this protocol is constructed in Alloy, a lightweight relational modeling language, and analyzed using the Alloy Analyzer, a fully automatic simulation and checking tool for Alloy models. In this analysis, some critical correctness properties that should be satisfied by any secure multicast protocol are checked. Some flaws, previously unknown to the protocol’s designers are exposed, including one serious security breach. To eliminate the most serious flaw, some fixes are proposed and checked using the Alloy Analyzer. The case study also illustrates a novel modeling idiom that supports better modularity and is generally simpler and more intuitive than the conventional idiom used for modeling distributed systems.
A simple technique to significantly enhance slew rate and bandwidth of one-stage CMOS operational amplifiers

A simple technique to modify a conventional one-stage op-amp for operation as a class AB amplifier is discussed. This technique leads to significant slew rate and bandwidth enhancement with essentially equal silicon area and static power dissipation requirements. Experimental results of test chip prototype in 0.5 /spl mu/m CMOS technology are presented. Results verify slew rate and bandwidth enhancement factors of almost one order of magnitude.
Rongorongo, The Easter Island Script: History, Traditions, Texts.

Rongorongo, The Easter Island Script: History, Traditions, Texts. Steven Roger Fischer. Oxford Studies in Anthropological Linguistics 14. Oxford: Clarendon Press, 1997. 714 pp.
Impact of process design on greenhouse gas (GHG) generation by wastewater treatment plants

The overall on-site and off-site greenhouse gas emissions by wastewater treatment plants (WWTPs) of food processing industry were estimated by using an elaborate mathematical model. Three different types of treatment processes including aerobic, anaerobic and hybrid anaerobic/aerobic processes were examined in this study. The overall on-site emissions were 1952, 1992, and 2435 kg CO2e/d while the off-site emissions were 1313, 4631, and 5205 kg CO2e/d for the aerobic, anaerobic and hybrid treatment systems, respectively, when treating a wastewater at 2000 kg BOD/d. The on-site biological processes made the highest contribution to GHG emissions in the aerobic treatment system while the highest emissions in anaerobic and hybrid treatment systems were obtained by off-site GHG emissions, mainly due to on-site material usage. Biogas recovery and reuse as fuel cover the total energy needs of the treatment plants for aeration, heating and electricity for all three types of operations, and considerably reduce GHG emissions by 512, 673, and 988 kg CO2e/d from a total of 3265, 6625, and 7640 kg CO2e/d for aerobic, anaerobic, and hybrid treatment systems, respectively. Considering the off-site GHG emissions, aerobic treatment is the least GHG producing type of treatment contrary to what has been reported in the literature.
Oral contraceptive use and risk of melanoma in premenopausal women.

Melanoma has been increasing in white populations. Incidence rates rise steeply in women until about age 50, suggesting oestrogen as a possible risk factor. Oestrogens can increase melanocyte count and melanin content and cause hyperpigmentation of the skin. We examined prospectively the association between oral contraceptive (OC) use and diagnoses of superficial spreading and nodular melanoma among 183 693 premenopausal white women in the Nurses’ Health Study (NHS) and the Nurses’ Health Study II (NHS II) cohorts. One hundred and forty six cases were confirmed in NHS during follow-up from 1976 to 1994, and 106 cases were confirmed in NHS II from 1989 to 1995. Skin reaction to sun exposure, sunburn history, mole counts, hair colour, family history of melanoma, parity, height and body mass index were also assessed and included in logistic regression models. A significant twofold increase in risk of melanoma (relative risk (RR) = 2.0, 95% confidence interval (CI) 1.2–3.4) was observed among current OC users compared to never users. Risk was further increased among current users with 10 or more years of use (RR = 3.4, 95% CI 1.7–7.0). Risk did not appear elevated among past OC users, even among those with longer durations of use, and risk did not decline linearly with time since last use. In conclusion, risk of premenopausal melanoma may be increased among women who are current OC users, particularly among those with longer durations of use. Further research is needed to determine whether low-dose oestrogen pills in particular are associated with an increase in risk and to describe possible interactions between OC use and sun exposure or other risk factors for melanoma. © 1999 Cancer Research Campaign
Emergent clustering methods for empirical OM research

Abstract To date, the vast majority of cluster analysis applications in OM research have relied on traditional hierarchical (e.g., Ward's algorithm) and nonhierarchical (e.g., K -means algorithms) methods. Although these venerable methods should continue to be employed effectively in the OM literature, we also believe there is a significant opportunity to expand the scope of clustering methods to emergent techniques. We provide an overview of some alternative clustering procedures (including advantages and disadvantages), identify software programs for implementing them, and discuss the circumstances where they might be employed gainfully in OM research. The implementation of emergent clustering methods in the OM literature should enable researchers to offer implications for practice that might not have been uncovered with traditional methods.
Free-running rhythms of adrenocorticotropic hormone (ACTH), cortisol and melatonin in pigs.

Abstract In the domestic pig, a circadian rhythm of plasma cortisol occurs, with greatest concentrations in the morning and lowest concentrations in the afternoon. However, photic entrainment of the rhythms of ACTH and melatonin in pigs have not been defined clearly. This experiment was designed to evaluate free-running rhythms of ACTH, cortisol and melatonin in pigs housed in constant light (LL) and constant darkness (DD). Twelve crossbred barrows, maintained under ambient photoperiod, were catheterized and tethered individually in two environmentally controlled rooms, one with LL and the other with DD. For animals in LL, fluorescent lights provided 202 ± 15 (mean ± standard deviation) lux of light at 65 cm above the floors. Incandescent nightlights equipped with 7 watt red bulbs provided 7 ± 2 lux and were illuminated continuously in both rooms. Pigs were given at least 14 d exposure to LL and DD, then samples of plasma and serum were obtained at hourly intervals for 48 hr. Plasma was assayed for ACTH, and serum for cortisol and melatonin. Periodograms were constructed to analyze the data. For this type of analysis, a statistic, Q p , is calculated, and circadian periodicity is suggested if maximum Q p (Q p max ) occurs at or near 24 hr. The period of the free-running rhythms (τ) at Q p max for ACTH, cortisol and melatonin for pigs in LL (23.80 ± .01, 23.78 ± .01, and 23.21 ± .02 hr, respectively) did not differ significantly from those for pigs in DD (23.39 ± .01, 23.20 ± .01, and 22.55 ± .02 hr, respectively). For both treatments combined, Q p at τ =24 hr was greater (P p at τ =20, 21, 25, 26, 27 and 28 hr for all three hormones. Unexpectedly, mean concentration of ACTH was greater (P
The biological utilization of N-pyridoxylamines.

Abstract Ethyl N -pyridoxyl- p -aminobenzoate and the m -aminobenzoate were utilized with considerable ease by rats and microorganisms as a source of vitamin B 6 . The activity of the aminobenzoates for the growth of rats was 100 % of that of free pyridoxine on a molar basis. For the growth of Saccharomyces carlsbergensis (A. T. C. C. 4228), the activity was found to be 20% for the p -aminobenzoate and 41% for the m -aminobenzoate. In rats, ethyl N -pyridoxyl- p -aminobenzoate was utilized as a source of vitamin B 6 solely via pyridoxal, whereas N -pyridoxyl-β-phenylethylamine was utilized via pyridoxal and pyridoxamine. Rats given massive doses of pyridoxal excreted considerable amounts of vitamin B 6 in an unknown, apparently conjugated form.
A n estimate for measures of hyperplane sections of convex bodies

The hyperplane (or slicing) problem asks whether there exists an absolute constant C so that for any origin-symmetric convex body K in Rn |K|n−1n⩽Cmaxξ∈Sn−1|K∩ξ⊥|, where ξ⊥ is the central hyperplane in Rn perpendicular to ξ, and |K| stands for volume of proper dimension. The problem is still open, with the best-to-date estimate C∼n1/4 established by Klartag, who slightly improved the previous estimate of Bourgain. It is much easier to get a weaker estimate with C=n. In this note we show that the n estimate holds for arbitrary measure in place of volume. Namely, if L is an origin-symmetric convex body in Rn and μ is a measure with non-negative even continuous density on L, then μ(L)⩽nnn−1cnmaxξ∈Sn−1μ(L∩ξ⊥)|L|1/n, where cn=|B2n|n−1n/|B2n−1|<1, and B2n is the unit Euclidean ball in Rn. We deduce this inequality from a stability result for intersection bodies.
Age of the North Atlantic Ocean from magnetic anomalies

Abstract Magnetic anomaly lineations have been identified in the North Atlantic. These lineations correlate with the magnetic time scale describing magnetic polarity reversals for the past 71 my. The results indicate that approximately 70% of the total drift between Europe and North America has occurred in the past 72 my, whereas only about 35% of the total drift between Africa and North America has happened in the same period. Extrapolation using the magnetic anomaly data and the results of JOIDES drilling suggests that drift between Africa and North America was initiated about 180 mybp.
A coupled atmosphere-sea ice model study of the role of sea ice in climatic predictability

Abstract The potential role of early autumn sea ice extent as a Predictor of late autumn climatic anomalies is investigated with a coupled atmosphere-sea ice model. Two ensembles of four simulations, one with an initially large ice extent and one with a small extent, are made and a 30-day mean, late autumn climatic state is calculated for each ensemble. The mean states are compared in order to determine how the initial difference in ice cover evolves, whether statistically significant differences exist between ensemble-mean climatic states, and what mechanisms are responsible for the differences. The late autumn ice covers of the two ensembles differ principally in the thickness of ice rather than ice extent. Statistically significant regional differences in the 750 mb streamfunction and potential temperature exist but appear to be of limited value for forecasting midlatitude climatic anomalies. There is a stronger surface cooling of the atmosphere in the ensemble with thicker ice which is compensated by ...
Early-Onset Heparin-Induced Thrombocytopenia After a 165-Day Heparin-Free Interval: Case Report and Review of the Literature

Early- or abrupt-onset immune-mediated heparin-induced thrombocytopenia (HIT) is defined as HIT that occurs less than 5 days after exposure to heparin in patients who have received heparin within the previous 100 days. We identified no reports in the literature of early-onset HIT in patients who had a heparin-free interval longer than 100 days. However, we report a case of early-onset immune-mediated HIT illustrated by a positive HIT result with serotonin release and enzyme-linked immunosorbent assays, and a decrease in platelet count to less than 100 x 10(3)/mm3 with no evidence of thrombosis, approximately 165 days after the patient's last exposure to heparin. We conclude that clinicians should choose alternative forms of anticoagulation in patients with even a remote history of HIT. If clinicians are compelled to reexpose patients to heparin, they should confirm a negative HIT assay result, monitor for clinical signs of HIT, and provide appropriate treatment if HIT is suspected.
Direct and indirect speech in Mambila

the first person pronoun I refers to the participant who is identified as speaker in the preceding clause (7ohn said to Peter) and the second person you refers to the participant identified as addressee. Of the two clauses involved, the second or embedded clause ('I can see you') may conveniently be referred to as the QUOTATION CONTENT. The first or main clause may be referred to as the REPORTING CLAUSE; this corresponds to the use of the term MARGIN in recent studies from the Summer Institute of Linguistics (Lowe, I969; Pike, I966; Pike & Lowe, I969) from which the inspiration for this paper has been taken. Any third person reference in the quotation content in direct speech must refer to a participant who is neither speaker nor addressee in the reporting clause. Indirect speech, by contrast, takes its pronoun orientation from one of two sources. If it is itself embedded in direct speech, then it takes its orientation from the reporting clause by which the direct speech is in turn dominated. For example, in the sentence:
Linear Regression Analysis for Highly Stratified Failure Time Data

Abstract In this article we consider cases where data consist of many small and independent groups of correlated failure time observations. For each failure time, which may be censored, some important covariates are also recorded. Our goal is to examine the covariate effects on the individual failure time observations. We assume that the logarithm of each failure time is linearly related to its covariates. We then take a population-averaged model approach to obtain inference procedures for the regression parameters without specifying the joint distribution of the observations within the group. The new proposals do not need complicated and unstable nonparametric estimates for the hazard function of the error term. Their properties are extensively examined for practical sample sizes. Comparisons among various procedures are also performed. All the methods studied in this article are illustrated with examples.
MRI as a reliable and accurate method for assessment of posterior hip dislocation in children and adolescents without the risk of radiation exposure

Background Posterior hip dislocation in children and adolescents may involve the non-ossified posterior acetabular wall. Plain radiographs and computed tomography (CT) have been shown to underestimate injury to the unossified acetabulum as well as associated soft-tissue structures.
The DNA binding domain and bending angle of E. coli CAP protein

Abstract We use a new gel electrophoretic analysis to map the thermodynamically defined DNA binding domain of Escherichia coli CAP protein in the lac promoter. Strong binding interactions span a 28–30 bp duplex DNA region, substantially larger than that found for typical repressors. Sequence changes outside the central 28 bp of the binding site are found to affect the electrophoretically observed extent of bending. We also report a study of the DNA bending induced at a symmetrized CAP binding site, compared with the wild-type site; binding and bending are stronger at the upstream than at the downstream half of the wild-type site. Bends of the estimated 90°–180° magnitude could play a vital regulatory role by producing tertiary structure in a local DNA domain, and by storing elastic energy for subsequent use in transcription or replication.
Evaluation and approximate evaluation of the multivariate Bernstein-Bézier form on a regularly partitioned simplex

Polynomials of the total degree d in m variables have a geometrically intuitive representation in the Bernstein-Be´zier form defined over an m-dimensional simplex. The two algorithms given in this article evaluate the Bernstein-Be´zier form on a large number of points corresponding to a regular partition of the simplicial domain. The first algorithm is an adaptation of isoparametric evaluation. The second is a subdivision algorithm. In contrast to de Casteljau's algorithm, both algorithms have a cost of evaluation per point that is linear in the degree regardless of the number of variables. To demonstrate practicality, implementations of both algorithms on a triangular domain are compared with generic implementations of six algorithms in the literature.
miR-155 promotes macroscopic tumor formation yet inhibits tumor dissemination from mammary fat pads to the lung by preventing EMT

A micro-RNA, miR-155, is overexpressed in many types of cancer cells, including breast cancer, and its role(s) in tumor metastasis has been studied on a very limited basis. Tumor metastasis is a multi-step process with the last step in the process being formation of macroscopic tumor in organs distant from the primary tumor site. This step is the least studied. Here, we report that stable expression of miR-155 in 4T1 breast tumor cells reduces significantly the aggressiveness of tumor cell dissemination as a result of preventing epithelial-to-mesenchymal transition (EMT) of tumor cells in vivo. Further, miR-155 directly suppresses the expression of the transcription factor TCF4, which is an important regulator of EMT. However, when tumor cells are injected directly into the bloodstream, miR-155 remarkably promotes macroscopic tumor formation in the lung. Analysis of gene expression profiling identified a group of genes that are associated with promoting macroscopic tumor formation in the lung. Importantly, most of these genes are overexpressed in epithelial cells. Our findings provide new insight into how miR-155 modulates the development of tumor metastasis. This study suggests that the location of tumor cells overexpressing miR-155 is a critical factor: in mammary fat pads miR-155 prevents tumor dissemination; whereas in the lung miR-155 apparently maintains the epithelial phenotype of tumor cells that is critical for macroscopic tumor formation.
Relationship between leisure-time physical activity and metabolic syndrome using varying definitions: 1999-2004 NHANES

Purpose: To examine the relationship between leisure-time physical activity (LTPA) and the metabolic syndrome in the U.S. adult population.Methods: The sample (N=5,620) in this cross-sectional study included adults aged 20 years and older. Physical activity was measured in two ways: a six-level measure based upon those reporting no LTPA and quintiles of LTPA, and a three-level categorical measure, according to participants who were found to be inactive, insufficiently active, and those meeting the current public health PA recommendation. SAS and SUDAAN were used for the statistical analysis.Results: When utilising the AHA/NHLBI criteria, adults acquiring between 736 and 1,360 MET·minutes per week (MET·min·wk-1) of LTPA were found to be 35% (OR 0.65; 95% CI 0.48, 0.88) less likely to meet the metabolic syndrome diagnosis criteria compared with those reporting no LTPA. However, protection (OR 0.70; 95% CI 0.51, 0.96) started earlier when utilising the WHO criteria (393—737 MET·min·wk-1). Significant inverse...
Classification, Diagnosis and Treatment of Vascular Dementia

Vascular dementia (VAD) is considered to be the second most common cause of dementia in Europe and the US. In Asia and many developing countries, it is more common than dementia of the Alzheimer's type (DAT). VAD is the most preventable form of dementia associated with later life. The pathogenesis of VAD is multifactorial, and it represents a heterogeneous, not a homogeneous, clinical entity. Classification of VAD by pathogenesis is important for its prevention and treatment. Control of the risk factors for VAD reduces its incidence and stabilises or improves cognitive performance following stroke. Proper diagnostic evaluation of VAD requires: (i) a well defined quantitative assessment of the cognitive deficits present; (ii) assessment of risk factors for stroke; (iii) identification of cerebral vascular lesions by history, neurological examination and neuroimaging; (iv) exclusion of other causes of dementia; (v) establishment of a positive diagnosis of possible, probable or definite VAD versus DAT or mixed VAD/DAT; and (vi) identification of the temporal relationship between cognitive deficits and cerebral vascular lesions. VAD can be subdivided into 8 major types, as follows: (i) multi-infarct dementia secondary to large cerebral emboli [type 1]; (ii) strategically placed infarctions causing dementia [type 2]; (iii) multiple subcortical lacunar lesions secondary to atherosclerosis or degenerative arteriolar changes [type 3]; (iv) Binswanger's disease (arteriosclerotic subcortical leukoencephalopathy) [type 4]; (v) mixtures of types 1, 2 and 3 [type 5]; (vi) haemorrhagic lesions causing dementia [type 6]; (vii) subcortical dementia secondary to hereditary factors (type 7); and (viii) mixtures of DAT and VAD (type 8). Treatment is dictated by the pathogenetic subtype of VAD that is present.
The coupled transverse vibrations of a spinning membrane disk with a central hub

Abstract The results of an investigation of the effect of hub coupling on the transverse free vibrations of a spinning membrane disk are presented. The equations of motion are formulated by an energy method and Rayleigh-Ritz procedure. It is found by using assumed modal distributions consisting of the normal modes for the spinning membrane with a rigidly clamped hub that the problem partitions into sub-problems associated with (i) symmetric vibrations involving only the generalized coordinates from the symmetric input modes, (ii) unsymmetric vibrations involving only the input modes with one nodal diameter, and (iii) unsymmetric vibrations involving input modes with more than one nodal diameter. The degree of hub coupling is found to depend primarily on the ratio of the mass of the membrane to the mass of the disk and on the ratio of the radius of the hub to the radius of the disk.
U-Th-Pb systematics of zircon inclusions in rock-forming minerals: A study of armoring against isotopic loss using the Sherman Granite of Colorado-Wyoming, USA

Zircon inclusions were separated from the five major rock-forming minerals of the Sherman Granite of southern Wyoming, in order to evaluate the degree of discordance as a possible function of host minerals. U-Th-Pb isotopic ratios were determined for two size fractions of zircon inclusions from each mineral, plus five size fractions from the bulk rock. Isotopic data from the inclusions have more than double the spread of data on a discordia obtained from the bulk sample, thereby yielding better-resolved concordia intercepts. However, isotopic ratios and morphologic characteristics indicate that the Pb/U systematics are complicated by inherited radiogenic lead. Although the data array cannot unequivocally be explained by the armoring process, the proposed methodology has succeeded in identifying groups of zircon with different isotopic characteristics. As such, this technique can be used to decipher complex geologic/isotopic histories and may be a useful addition to routine zircon geochronology.
Measuring Availability in the Domain Name System

The domain name system (DNS) is critical to Internet functionality. The availability of a domain name refers to its ability to be resolved correctly. We develop a model for server dependencies that is used as a basis for measuring availability. We introduce the minimum number of servers queried (MSQ) and redundancy as availability metrics and show how common DNS misconfigurations impact the availability of domain names. We apply the availability model to domain names from production DNS and observe that 6.7% of names exhibit sub-optimal MSQ, and 14% experience false redundancy. The MSQ and redundancy values can be optimized by proper maintenance of delegation records for zones.
Children's understanding of logical and conventional rules in arithmetic algorithms

Abstract The study examined third graders' ability to distinguish logical from conventional algorithm rules. Third graders performed written addition and subtraction algorithms, answered questions about the amounts exchanged in carrying and borrowing, and evaluated the alterability and relativity of two alternative rules: an alternative conventional rule, involving a conventional aspect of the algorithm (e.g., putting the answer above the problem, rather than below), which does not change the answer, and an alternative logical rule, involving a logical aspect of the algorithm (e.g., adding a carried “ten” to the hundreds column), which produces an incorrect answer. Results indicate that children know that using an alternative logical rule produces a different answer, but many do not judge this answer to be necessarily incorrect. Rather, they judge the correctness of both types of rules, as well as the answers produced by using the rules, to be conventional, and thus under the control of the teacher or other school authorities.
Menopausal symptom experience: an online forum study

Title. Menopausal symptom experience: an online forum study Aim. The aim of the study was to explore the menopausal symptom experience of White midlife women. Background. Recent cross-cultural investigations have indicated important ethnic differences in menopausal symptoms and have challenged the universality of these symptoms. Currently available cultural knowledge on menopausal experience, however, is inadequate to guide appropriate and adequate care even for White women in the menopausal transition. Method. A cross-sectional qualitative online forum study was conducted in 2007 with 23 midlife women who self-identified as non-Hispanic Whites using convenience sampling. Seven topics related to menopausal symptom experience were used to guide the online forum for 6 months. The data were analysed using thematic analysis. Results. The experiences of menopause caused women to redefine themselves within their busy daily life schedules. They were optimistic about their symptoms, and tried to laugh at the experience to boost their inner strength and motivate themselves to persevere. Many thought that both generational and life-style differences were much more important than ethnic differences in menopausal symptom experiences. In seeking assistance with the symptoms of menopause, women were not satisfied with the guidance of their physicians. Conclusion. Nurses need to listen carefully to what women themselves say about their own experiences with menopausal symptoms and avoid imposing predetermined symptom management strategies. Further studies of women’s perceptions of life-style influences are needed to guide symptom management. In addition, studies of generational changes in menopausal symptom experience are needed.
The effect of the thromboxane A2 receptor antagonist SQ 29,548 on the severity of pacing-induced ischemia.

The effect of the thromboxane A2 (TXA2)/prostaglandin endoperoxide receptor antagonist, SQ 29,548 on pacing-induced ischemia was determined in anesthetized open-chest dogs. The dogs were subjected to a left anterior descending coronary artery (LAD) stenosis sufficient to result in ischemia as measured by epicardial ST-segment elevation only when the hearts were paced 70-80 beats/min above baseline. After a recovery (nonpacing) period, either 0.2 mg/kg + 0.2 mg/kg/hr SQ 29,548 or saline was infused i.v. The animals were subjected to 5 min periods of pacing before and 10, 40 or 70 min after the initiation of drug or saline treatment. Before drug treatment, pacing + LAD stenosis resulted in significant ST-elevation in both groups (11.5 +/- 1.1 mV and 12.4 +/- 0.6 mV for saline and SQ 29,548 groups, respectively). During drug treatment, SQ 29,548 significantly reduced ST-elevation during pacing + stenosis at 40 and 70 min. At 70 min, ST-elevation was 4.9 +/- 1.7 mV for the SQ 29,548 group vs 10.8 +/- 1.2 mV for the saline group (p less than 0.05). In separate experiments 0.2 mg/kg + 0.2 mg/kg/hr SQ 29,548 antagonized the activity of a TXA2 mimetic, U-46,619, for femoral vasoconstriction, causing 100-to-200 fold rightward shifts in dose response relationships. Thus, a dose of SQ 29,548 capable of strong TXA2-receptor blockade reduced the severity of ischemia, and this effect was independent of changes in arterial blood pressure and heart rate.
Das Blaue Wunder in der Kataraktchirurgie

BACKGROUND Continuous circular capsulorhexis enabling safe phacoemulsification and implantation of the PC-IOL in the bag is extremely difficult to perform in the absence of red reflex. Staining of the anterior capsule with a vital dye (Vision blue(R); DORC, The Netherlands) allows easy capsulorhexis under such conditions. PATIENTS AND METHODS Because of missing or poor red reflex Vision blue(R) was applied to allow capsulorhexis in 26 eyes of 25 patients (aged 24 - 86 years). Sixteen patients had mature cataracts, two patients had dense vitreous opacities and 8 patients had pronounced anterior subcapsular opacifications. RESULTS Continuos circular capsulorhexis was easy to perform in 22/26 eyes after staining the anterior capsule with Vision blue(R). Due to increased intracapsular pressure two eyes developed an uncontrolled tearing of the anterior capsule towards the periphery, and in two eyes capsulotomy had to be completed with high-frequency capsulotomy or scissors. Ten of sixteen eyes with mature cataracts had extremely hard nuclei requiring extended phacoemulsification time (more than 90 seconds calculated for 100 % power). There was no rupture of the posterior capsule nor vitreous loss. All PC-IOL's (23 x Acrysof(R); Alcon; 3 x 6.5 mm PMMA) were implanted into the capsular bag. Preoperatively 19/26 eyes had visual acuity of handmotions or less, postoperatively 18/26 eyes achieved 20/30 or better visual acuity. CONCLUSIONS In the absence of red reflex staining of the anterior capsule with Vision blue(R) allows continuous circular capsulorhexis and implantation of the PC-IOL in the bag. An extremely hard nucleus requiring extended phacoemulsification time must be expected in elderly patients with mature cataracts.
Contact stress solutions using computer techniques

Abstract The use of a computer program to solve example problems involving contact stresses is presented as an initial step in the development of computerized stress analyses involving fretting fatigue loadings. The utilization of the computer greatly simplifies the calculation of contact stresses.
Diaphragmatic electromyogram power-spectral analysis as a function of reduced end-expiratory lung volume.

ABSTRACT: We examined the centroid frequency (Fc) of the electromyogram power-frequency spectra from the costal (EMGco) and crural (EMGcr) diaphragms at functional residual capacity and at reduced end-expiratory lung volume (EELV) (induced by abdominal banding) in six anesthetized newborn piglets. EMGco and EMGcr were recorded from bipolar electrodes embedded in the costal and crural diaphragms respectively. A fast Fourier transformation of ECG free EMGco and EMGcr was used to compute the power-frequency spectra and calculate the Fc of EMGco and EMGcr. The nitrogen washout technique was used to measure EELV. Abdominal banding induced a reduction in EELV of 30.6% functional residual capacity (range 22–39%). The mean Fc of EMGcr was not significantly altered by the reduction in EELV, whereas the mean Fc of the EMGco fell in every animal at reduced EELV by 13 ± 8% of baseline Fc (p < 0.05). We conclude that alterations in lung volume alone can determine changes in the EMGco power spectrum and Fc. Investigators performing EMGco power spectral analysis should consider EELV status when interpreting their findings.
Clinical impact of antibiotic resistance in respiratory tract infections

Streptococcus pneumoniae is the most common causative pathogen of community-acquired respiratory tract infections. In vitro evidence indicates that S. pneumoniae is increasingly resistant to commonly prescribed antimicrobial agents including the macrolides. The clinical relevance of resistance, however, has not been clearly established. This article reviews the risk factors influencing selection of resistant pneumococci, discusses endpoints used to assess the impact of resistance on clinical outcome, and proposes strategies to minimise the impact of resistance. Evidence demonstrating treatment failures due to macrolide-resistant S. pneumoniae is also reviewed. Increasing rates of resistance among S. pneumoniae present numerous clinical challenges, and require carefully selected treatment strategies to preserve antibacterial efficacy. Antibiotics with a low propensity for stimulating resistance should be chosen wherever possible.
Neuroprotection against neonatal hypoxia/ischemia-induced cerebral cell death by prevention of calpain-mediated mGluR1α truncation

Many cellular events are involved in ischemic neuronal death, and it has been difficult to identify those that play a critical role in the cascade triggered by lack of oxygen and glucose, although it has been widely recognized that overactivation of glutamate receptors represents one of the initiating factors. Different glutamate receptor antagonists, especially those for N-methyl-D-aspartate (NMDA) receptors, have achieved significant success in animal models of hypoxia/ischemia; however, these antagonists have failed in clinical trials. We previously reported that calpain-mediated truncation of metabotropic glutamate receptor 1alpha (mGluR1alpha) played a critical role in excitotoxicity, and that a TAT-mGluR1 peptide consisting of a peptide surrounding the calpain cleavage site of mGluR1alpha and the peptide transduction domain of the transactivating regulatory protein (TAT) of HIV was neuroprotective against excitotoxicity. In the present study we tested the effect of this peptide in in vitro and in vivo models of neonatal hypoxia/ischemia. TAT-mGluR1 peptide prevented oxygen/glucose deprivation- (OGD) and hypoxia/ischemia- (H/I) induced neuronal death in cultured hippocampal slices and neonatal rats, respectively. TAT-mGluR1 blocked H/I-induced mGluR1alpha degradation but had no effect on H/I-induced spectrin degradation, suggesting that neuroprotection was due to prevention of calpain-mediated mGluR1alpha truncation and not to calpain inhibition. Our results therefore suggest that mGluR1alpha truncation plays a critical role in neonatal hypoxia/ischemia and that blockade of this event may prevent the activation of many downstream cytotoxic cascades. Compared to glutamate receptor antagonists and general calpain inhibitors, TAT-mGluR1 may have limited side effects.
What's Negative about Positive Self Concept?

As an educator, you have probably been bombarded with the importance of helping students develop positive self-concepts. No one can easily deny the value of such an objective. Then why is the title emphasizing the negative? Much disservice has been done to students in the name of developing and encouraging positive selfconcepts without recognizing some of the limitations to this approach. An examination of these limitations may help dispel some myths. Considerable heat but little light has been generated by self-concept research. Hence, the statements that I make are evaluative, based upon clinical intuition rather than substantiated by empirical evidence. The first and most obvious shortcoming relates to the difficulty in measuring self-concept. Ruth Wylie (1974) concluded that the field is replete with theoretical, conceptual, and methodological flaws. This explains why Wylie stated, ". .After more than 20 years of research on the self-concept, no new instrument has been developed and validated using all of the relevant published conceptual and practical methodological guidelines." Another facet of the assessment problem was illustrated by Hansford and Hattie (1982). In an analysis of 128 studies they found a low, positive correlation (.21 to .26) between self perception and various performance/ achievement measures. They cautioned against concluding that there is a causal link between the two, mainly because there are numbers of uncontrollable variables and lack of covariation. Many respondents of self-concept inventories will give socially desirable responses. We are asking participants to tell us about themselves. Although some may feel comfortable telling us what they feel about themselves, those who require the greatest help and support may feel uncomfortable about self-disclosure. Some may express only that which is socially approved.
Morphology and crystalline perfection of InAs films on Si(100)

Abstract InAs films were deposited from In and As 4 fluxes on Si(100) substrates by ion-assisted deposition (IAD). The use of Ar ion irradiation during film nucleation improved the substrate coverage and crystalline perfection. The effect of As 4 -to-In flux ratio r As and substrate temperature T s on the nucleation, island coalescence, smoothening, and crystalline perfection of InAs films on Si(100) was studied using reflection high-energy electron diffraction (RHEED), scanning electron microscopy, and X-ray diffraction. Complete substrate coverage was achieved at the lowest film thickness by using r As ≈ 1 and T s ≈ 380°C. Continuous InAs films that gave streaky, reconstructed RHEED patterns were obtained at thickness of ≈ 800 nm. It was also found that the presence of anti-phase domains in InAs films led to residual surface roughness in thick films. The typical X-ray rocking curve full width at half-maximum was ≈ 3000 arc sec at a film thickness of 0.4 μm.