cssi/SciSciGPT-SciSciNet huggingface dataset:
2000s: New Field of Focus

The turn of the century arrived with great changes in the field, along with new physicians both staff and fellows from around the world who added great intellectual fervor and substance to the framework principles of science, education, and practice. Major opportunities included involvement in multiple large multicenter trials and registries analyzing data scientifically and applying the results to practice. Many of these trials and registries focused on acute ischemic syndromes including STEMI and non-STEMI infarction which evaluated the clinical questions of how to treat multivessel disease identified at the time of primary PCI. These trials also studied important subgroups of patients such as cardiogenic shock which was the focus of intense interest by Mayo investigators who significantly expanded our knowledge about this most lethal complication. The Mayo Clinic PCI Registry which had been initiated at the beginning of our involvement continued to enroll and follow all consecutive patients treated with PCI. This provided unique data on immediate complications such as the development of acute kidney injury and vascular access bleeding as well as the long-term data on patients with enzyme elevation post-procedure. Mayo had the opportunity to coordinate the largest randomized clinical trial (at that time) of medical approaches to prevent restenosis, as well as the initial and perhaps only randomized clinical trial of drug-eluting stents versus vascular brachytherapy for the treatment of in-stent restenosis of bare metal stents. An area of great interest which consumed much focus in the field was the “ticking time bomb” of drug-eluting stents and stent thrombosis. Much work was dedicated to identifying the risk factors for that, and testing and then putting in place strategies to mitigate the issue. Other areas of great importance for the field resulted in the development, testing, and eventual approval of the only FDA device for stroke prevention in patients with non-valvular atrial fibrillation who were at increased risk for stroke. As part of that effort, Mayo was the primary investigator in the only two randomized clinical trials of this device versus anticoagulation with warfarin, which documented proof of concept that the left atrial appendage was the nidus of stroke in this setting in the great majority of patients. This project was part of the beginning of cath lab focus in structural heart disease which would become dominant in the field.
Transition from ductile tearing to cleavage fracture: A cell-model approach

The fracture resistance of ferritic steels in the ductile/brittle transition regime is controlled by the competition between ductile tearing and cleavage fracture. Under typical conditions, a crack initiates and grows by ductile tearing but, ultimately, failure occurs by catastrophic cleavage fracture. In this computational study cleavage fracture is treated by a weakest link mechanism in conjunction with brittle microcrack statistics. The cleavage model also accounts for the competition between the nucleation of voids from the carbide inclusions on grain boundaries and the unstable cracking of these inclusions precipitating catastrophic cleavage fracture. The probabilistic treatment for the transition to catastrophic cleavage is phrased in terms of the Weibull stress, σ_W, reaching measurable material-specific values. The successful application of this cleavage fracture model hinges on an accurate description of the evolution of the stress field during crack growth by ductile tearing. This is accomplished by using cell elements endowed with the micro-separation characteristics of ductile tearing. Load-displacement behavior, ductile tearing resistance and transition to cleavage fracture are investigated for three different test geometries. Crack geometry, microstructure and ductile crack growth exert strong effects on the transition from ductile tearing to cleavage fracture. The model predicts trends in ductile/brittle transition that are consistent with experimental data.
Operator theory in function spaces

Bounded linear operators Interpolation of Banach spaces Integral operators on $L^p$ spaces Bergman spaces Bloch and Besov spaces The Berezin transform Toeplitz operators on the Bergman space Hankel operators on the Bergman space Hardy spaces and BMO Hankel operators on the Hardy space Composition operators Bibliography Index.
Argument Efficacy: Evaluating the Public Argument of President Bill Clinton's Impeachment Crisis

This study developed from a need to understand public definitional disputes. A review of literature revealed that while the importance of definition is clearly understood, the process of public arg...
Dawnward shift of the dayside O+ outflow distribution: The importance of field line history in O+ escape from the ionosphere

[1] Observations and modeling of thermal upwelling O+in the topside ionosphere are used to demonstrate that the well-known dawnward shift of energetic escaping fluxes at higher altitudes is the result of the expansion and contraction of low energy plasma on magnetic field lines and noon focused energization mechanisms. Recent research has shown that magnetospheric impacts of ion outflow are dependent on the local time source location. However, most modelers assume that the peak escaping O+ flux on the dayside is coincident with energy inputs from the magnetosphere associated with the cusp. The dawnward offset has been observed by multiple spacecraft and most recently in a new DMSP database of low altitude upwelling O+. The documented control of the cusp orientation with the Y component of the interplanetary magnetic field is generally a smaller effect than the observed dawnward bias. The dawnward offset is largest for thermal O+ during geomagnetically quiet intervals and smallest for energetic escaping O+ during active intervals. The present study investigates the efficacy of precipitating electrons, solar irradiance and neutral winds on dayside upwelling O+. An ionosphere model is used to show that solar irradiance causes significant upwelling O+ on dawn flux tubes and when combined with noon focused energization mechanisms, establishes the observed dayside escaping energetic O+ flux distribution. Our analysis also reveals that, during geomagnetically quiet intervals, high latitude neutral winds may be as important as electron precipitation in establishing the dayside distribution of upflowing thermal O+.
Access to Mathematics and Science

The task of entering into careers in math and science is one of difficulty for all students. For the visually impaired student, the task is even more daunting. In our STS, we will hear a number of excellent papers and see several exciting demonstrations concerning making math, and therefore science, accessible to the visually impaired.
Economic Development, Poverty, and Antitrust: The Other Path

Developed countries often insist that antitrust is only for efficiency and consumer welfare, and that any broader focus will protect small competitors and mire the economy in inefficiencies. Developing countries retort that their antitrust must also address issues of distribution and power. This article contests the standard Western claim that if conduct cannot be shown to raise prices to consumers it must be efficient and should be beyond antitrust challenge. It also argues that developing countries need a broader standard than whether conduct decreases aggregate consumer or total wealth. Developing country antitrust should not be used to protect inefficient Davids against Goliath, but it may and should be used to empower Davids against Goliath by keeping open paths of mobility and access. Indeed, enhanced mobility tends to produce efficiencies in societies in which economic opportunity of masses of people has been suppressed. An antitrust law for developing countries that values mobility, access and efficient development of the economy, while not protecting small firms at the expense of consumers, is The Other Path of the title to this article. The article articulates principles, factors and strategies that give content to this other path.
Influences of conjugal genetic transfer functions of colicin V plasmids on adhesion of Escherichia coli to murine intestinal tissue.

Cells of strains of Escherichia coli K-12 291 bearing one of three colicin V plasmids, pF54, pH247, or pF70, were tested in comparison with cells of strain 291 for their ability to adhere to murine intestinal tissue in vitro. The plasmids were either repressed or derepressed in conjugal genetic transfer functions. The strains bearing pF54 and pH247 repressed in transfer functions (pColVF54 luminal diameter r and pColVH247 luminal diameter r) adhered in higher numbers to the murine tissue than did the host strain lacking the plasmid or the strains containing the plasmids with active transfer functions (pColVF54drd and pColVH247drd). The number of cells (CFU) of strain 291(pColVF54 luminal diameter r) adherent to the tissue was related directly to the time of incubation (up to 30 min) and to the number of cells (CFU) to which the tissues were exposed. As indicated by tests for sensitivity to F factor (F)-pilus-specific bacteriophages, the cells of strains bearing the plasmids derepressed for conjugal functions had F pili on their surfaces, while such structures were missing from cells of the parental strain (291) and the strains containing the plasmids in repressed form. This finding was supported by transmission electron microscopy of cells of strain 291, 291(pColVF54 luminal diameter r), and 291(pColVF54drd). F pili could be seen on cells of the latter strain but not on those of the parental strain or the strain bearing pColVF54 luminal diameter r. Pili other than F pili were not seen on cells of the strains bearing pF54 in either form. Strains 291(pColVF70drd) and 291(pColVF70 luminal diameter r) adhered to the tissues in numbers comparable to those of strain 291. Nevertheless, these findings are further evidence that for certain colicin V plasmids (A. M. Nilius and D. C. Savage, Infect. Immun. 43:947-953, 1984), conjugal genetic transfer functions influence properties that may be important in the pathogenesis of invasive E. coli strains. Images
Incidence of Infestation and Larval Success of Emerald Ash Borer (Agrilus planipennis) on White Fringetree (Chionanthus virginicus), Chinese Fringetree (Chionanthus retusus), and Devilwood (Osmanthus americanus)

We compared the incidence of infestation by emerald ash borer (EAB) and lilac borer on white fringetree to that of its Asian congener, Chinese fringetree, Chionanthus retusus, and a North American relative, devilwood, Osmanthus americanus. We also conducted laboratory bioassays to determine the suitability of these hosts for EAB larvae. At Spring Grove Cemetery and Arboretum in Cincinnati, Ohio, 9 of 28 white fringetrees examined were infested by EAB. Most of the white fringetrees had lilac borer infestation, and most of the trees infested by EAB also had lilac borer infestation. None of the 11 Chinese fringetrees examined were infested by either EAB or lilac borer. Each of the five devilwood individuals examined was infested by lilac borer, but not EAB. At The Morton Arboretum in Lisle, Illinois, 7 of 16 white fringetrees examined were infested by EAB, while none of the seven Chinese fringetrees examined were infested by either insect. A 40-d bioassay confirmed that white fringetree was an acceptable host, producing fourth-instar larvae that were smaller than those produced on a highly susceptible cultivar of green ash, Fraxinus pennsylvanica. No larvae survived on Chinese fringetree, and neonates were largely incapable of feeding on it. Two larvae survived on devilwood, reaching the second instar and excavating extensive galleries. Future work should be aimed at biotic and abiotic factors influencing the susceptibility of white fringetree, as well as further examination of close relatives for their vulnerability to EAB.
A Season of Fire: Four Months on the Firelines of America's Forests

Book Review: A Season of Fire: Four Months on the Firelines of America’s Forests, Douglas Gatenbein. Penguin Group (USA) Inc., New York (2003).
Sequential excision and grafting of the burn injuries of 1507 patients treated between 1967 and 1986: end results and the determinants of death.

The development of a more aggressive approach to burn wound management, leading to complete excision within 72 hours after burn, has led some to conclude that total early excision is a major force behind improved survival rates. We have summarized the results of treatment of 1507 patients with burn injuries treated between 1967 and 1986. Wounds were managed with use of standard topical therapy, occlusive dressings, and staged excision and grafting of full-thickness injury or deep dermal injury (not healed by 21 days). Data were analyzed with use of a logistic-regression model because, with the exception of older patient cohorts, the data did not fit the probit model. The major determinants predicting death were the percentage of body surface area burned, age 2 , smoke inhalation, and the percentage of full-thickness burn. Concordance was 97%. These data show that aggressive sequential wound excision and grafting produces end results comparable with those achieved with complete early burn wound excision for similar age ranges and injury. Early harvest of available donor sites in patients with large burns may be more important to survival than complete early wound excision.
Update on contraceptive options: A case-based discussion.

Abstract As health care providers, we must engage our female patients in a dialogue about their contraceptive and fertility decisions. Empowering and educating our patients about their bodies' hormones, the menstrual cycle, and the risk of unintended pregnancy are central to effective contraceptive counseling. Selecting an appropriate method for a patient and her medical profile is rewarding and challenging in view of new medications, novel delivery systems, and evolving research.
The Roles and Responsibilities of Kinesiology Regarding Sport

This article is a response to the 2013 NAKHE meeting in San Diego, California. The assigned strand was the roles and responsibilities of kinesiology regarding sport. The article is a response of the strand leader, comments from the participants in the strand, and possible solutions to the strand direction.
Redundancy as a way of life - IAA metabolism

Plants have evolved elaborate systems for regulating cellular levels of indole-3-acetic acid (IAA). The redundancy of this network has complicated the elucidation of IAA metabolism, but molecular genetic studies and precise analytical methods have begun to expose the circuitry. It is now clear that plants synthesize, inactivate and catabolize IAA by multiple pathways, and multiple genes can encode a particular enzyme within a pathway. A number of these genes are now cloned, which greatly facilitates the future dissection of IAA metabolism.
Defining reward value by cross-modal scaling.

Researchers in comparative psychology often use different food rewards in their studies, with food values defined by a pre-experimental preference test. While this technique rank orders food values, it provides limited information about value differences because preferences may reflect not only value differences, but also the degree to which one good may “substitute” for another (e.g., one food may substitute well for another food, but neither substitutes well for water). We propose scaling the value of food pairs by a third food that is less substitutable for either food offered in preference tests (cross-modal scaling). Here, Cebus monkeys chose between four pairwise alternatives: fruits A versus B; cereal amount X versus fruit A and cereal amount Y versus fruit B where X and Y were adjusted to produce indifference between each cereal amount and each fruit; and cereal amounts X versus Y. When choice was between perfect substitutes (different cereal amounts), preferences were nearly absolute; so too when choice was between close substitutes (fruits); however, when choice was between fruits and cereal amounts, preferences were more modest and less likely due to substitutability. These results suggest that scaling between-good value differences in terms of a third, less-substitutable good may be better than simple preference tests in defining between-good value differences.
Utility of the Gyrus open forceps in hepatic parenchymal transection

Abstract Objective This study aimed to evaluate if the Gyrus open forceps is a safe and efficient tool for hepatic parenchymal transection. Background Blood loss during hepatic transection remains a significant risk factor for morbidity and mortality associated with liver surgery. Various electrosurgical devices have been engineered to reduce blood loss. The Gyrus open forceps is a bipolar cautery device which has recently been introduced into hepatic surgery. Methods We conducted a single-institution, retrospective review of all liver resections performed from November 2005 through November 2007. Patients undergoing resection of at least two liver segments where the Gyrus was the primary method of transection were included. Patient charts were reviewed; clinicopathological data were collected. Results Of the 215 open liver resections performed during the study period, 47 patients met the inclusion criteria. Mean patient age was 61 years; 34% were female. The majority required resection for malignant disease (94%); frequent indications included colorectal metastasis (66%), hepatocellular carcinoma (6%) and cholangiocarcinoma (4%). Right hemihepatectomy (49%), left hemihepatectomy (13%) and right trisectionectomy (13%) were the most frequently performed procedures. A total of 26 patients (55%) underwent a major ancillary procedure concurrently. There were no operative mortalities. Median operative time was 220 min (range 97–398 min). Inflow occlusion was required in nine patients (19%) for a median time of 12 min (range 3–30 min). Median total estimated blood loss was 400 ml (range 10–2000 ml) and 10 patients (21%) required perioperative transfusion. All patients had macroscopically negative margins. Median length of stay was 8 days. Two patients (4%) had clinically significant bile leak. The 30-day postoperative mortality was zero. Conclusions Use of the Gyrus open forceps appears to be a safe and efficient manner of hepatic parenchymal transection which allows rapid transection with acceptable blood loss, a low rate of perioperative transfusion, and minimal postoperative bile leak.
The roles of the exchange rate and the foreign interest rate in Estonia's money demand function and policy implications

The demand for real M2 in Estonia is positively influenced by real income, real stock prices and the depreciation of the kroon, and negatively associated with the deposit rate, the euro interest rate and the expected inflation rate. Hence, a higher euro interest rate would help raise Estonian real output, and the depreciation of the kroon may or may not raise real output. The Box–Cox transformation test shows that the double-log form cannot be rejected at the 5% level while the linear form can be rejected at the 5% level. The CUSUMSQ test shows that parameters in the money demand function are stable.
Explosion Effects and Earthquakes in the Amchitka Island Region

Microearthquakes were monitored by a network of seismographs located on Amchitka and nearby islands; the nature of earthquake activity in this region was found to be consistent with the hypothesis of underthrusting of the Aleutian arc by a rigid lithospheric plate. Seismic effects of the nuclear explosion Milrow were small, of short duration, confined to the region immediate to the explosion, and were apparently independent of this geotectonic mechanism.
Are educational aspirations associated with the risk of alcohol use and alcohol use-related problems among adolescents?

Objective: Using prospective data, we hypothesized that public middle school students with high educational aspirations would report less alcohol use, and alcohol use-related problems in the subsequent year. Methods: The participants for these analyses included students, ages 11 to 14 years old, participating in a longitudinal study in an urban sample of public schools (n = 1229). As part of the prospective annual assessments of the students, in 1992 (t0) and 1993 (t1), data on educational aspirations and on alcohol use, and alcohol use-related problems were gathered. Latent variable modeling was used to assess the relationship between educational aspirations at baseline (t0) and subsequent year drinking behavior (t1) in two separate models, one to examine the relationship of educational aspirations with self-reported alcohol use (model 1), and another to examine the association with alcohol use-related problems (model 2). Potential confounding by age, sex, race-ethnicity, alcohol use by peers, self-repor...
Teachers as researchers: a narrative pedagogical approach to transforming a graduate family and health promotion course.

Abstract Scholarship of teaching in nursing is illustrated by describing the development, implementation, evaluation, and revision of a family and health promotion course for graduate family nurse practitioner students. A narrative pedagogical approach that combines conventional pedagogy with action research is used. The work, an example of curriculum as dialogue, illustrates how teachers can incorporate research, evaluation, and reflection into their daily teaching practice. Given adequate support, these evaluation and research activities could constitute part of the scholarship of teaching, and, as such, would warrant allocation of time in faculty workloads and formal acknowledgment in annual performance evaluations and promotion and tenure decisions. The importance of increasing the clinical relevance of the scholarship of teaching in a practice discipline such as nursing is also emphasized.
Connections between quantum chromodynamics and condensed matter physics

Features of QCD can be seen qualitatively in certain condensed matter systems. Recently some of the analyses that originated in condensed matter physics have found applications in QCD. Using examples we discuss some of the connections between the two fields and show how progress can be made by exploiting this connection. Some of the challenges that remain in the two fields are quite similar. We argue that recent algorithmic developments call for optimism in both fields.
The sizes of the photosynthetic energy-transducing units in purple bacteria determined by single flash yield, titration by antibiotics and carotenoid absorption band shift

Several approaches to find out the size of energy-transducing unit in ion transport and photophosphorylation in chromatophores of photosynthetic bacteria (Chromatium Strain D, Rhodospirillum rubrum and Rhodopseudomonas spheroides) were applied. Single flash yield (A), titration of ion transport by ionophorous antibiotics (B), and titration of the shift of carotenoid absorption band by antibiotics (C) were the methods used. Method A gave the values of 50–60 as chlorophyll/hydrogen ratio for nonphosphorylating H+ gradient formation, and the value of 25 for the phosphorylating H+ change. By Method B, the value of 200–400 was obtained as the molar ratio of chlorophyll to the gradient collapsing agent. By Method C, much larger values (2000–5000) were obtained as the molar ratio of chlorophyll/ionophore, when we measured the effect of valinomycin on the dark recovery rate constants of carotenoid shift. The different biophysical aspects of these “photosynthetic units” are discussed.
Epidemiology of aortic aneurysm in the United States

Recent apparent increases in occurrence of aortic aneurysm were reported for abdominal aortic aneurysm from several countries. In order to assess U.S. trends, an analysis of mortality and hospitalization data from the National Center for Health Statistics for aortic aneurysm in the United States in 1979-1992 was performed. In 1991, 16,696 deaths were attributed to aortic aneurysm, abdominal aneurysm accounting for 52%. Between 1979 and 1990, dissecting aneurysm death rates showed inconsistent changes in males and slight increases in females. Age-adjusted rates were higher in blacks than whites, and in males than females. Death rates for abdominal aneurysms showed slight decreases in white males and slight increases in black males and white females. Rates were higher in whites than blacks, and in males than females. The number of hospital discharges with a first-listed diagnosis of aortic aneurysm increased from 39,000 in 1979 to 67,000 in 1992. The rate of diagnoses increased from 1979 to 1984 with no consistent change thereafter for total and abdominal aneurysms, which comprised over 75% of total diagnoses. The number of all-listed aortic aneurysm resections with graft replacement increased from 10,000 in 1979 to 40,000 in 1988 with no consistent change thereafter. Increased utilization of diagnostic ultrasound of the abdomen and retroperitoneum leading to improved case finding for abdominal aneurysms may have been one cause of increasing hospital discharge rates prior to 1985. Continued monitoring of national data on mortality and morbidity from aortic aneurysms is desirable to assess effects of diagnostic, therapeutic, and preventive interventions.
Rewriting the Climatology of the Tropical North Atlantic and Caribbean Sea Atmosphere

Abstract The Jordan mean tropical sounding has provided a benchmark reference for representing the climatology of the tropical North Atlantic and Caribbean Sea atmosphere for over 50 years. However, recent observations and studies have suggested that during the months of the North Atlantic hurricane season, this region of the world is affected by multiple air masses with very distinct thermodynamic and kinematic characteristics. This study examined ∼6000 rawinsonde observations from the Caribbean Sea region taken during the core months (July–October) of the 1995–2002 hurricane seasons. It was found that single mean soundings created from this new dataset were very similar to C. L. Jordan’s 1958 sounding work. However, recently developed multispectral satellite imagery that can track low- to midlevel dry air masses indicated that the 1995–2002 hurricane season dataset (and likely Jordan’s dataset as well) was dominated by three distinct air masses: moist tropical (MT), Saharan air layer (SAL), and midlatit...
Carbohydrate microarrays for the recognition of cross-reactive molecular markers of microbes and host cells

We describe here the development of a carbohydrate-based microarray to extend the scope of biomedical research on carbohydrate-mediated molecular recognition and anti-infection responses. We have demonstrated that microbial polysaccharides can be immobilized on a surface-modified glass slide without chemical conjugation. With this procedure, a large repertoire of microbial antigens (∼20,000 spots) can be patterned on a single micro-glass slide, reaching the capacity to include most common pathogens. Glycoconjugates of different structural characteristics are shown here to be applicable for microarray fabrication, extending the repertoires of diversity and complexity of carbohydrate microarrays. The printed microarrays can be air-dried and stably stored at room temperature for long periods of time. In addition, the system is highly sensitive, allowing simultaneous detection of a broad spectrum of antibody specificities with as little as a few microliters of serum specimen. Finally, the potential of carbohydrate microarrays is demonstrated by the discovery of previously undescribed cellular markers, Dex-Ids.
Design technique for a spiral planar winding with geometric radii

Design issues concerning the construction of a planar spiral winding with geometric width for use in low-profile magnetic components are presented, along with a practical method to achieve low resistance. Equations for resistance predictions are developed for constant- and variable-width pattern designs. Finite-element simulation, (FES) suggests that the winding resistance of a spiral winding with geometric radii may be calculated from the closed-form winding resistance equation of a toroidal planar winding which has the same copper area as the spiral planar winding. Resistance measurement of a sample winding design is presented and compared against analytical prediction.
Gender differences in the treatment of cerebrovascular disease.

OBJECTIVE: Previous studies have shown that women receive fewer invasive procedures for the treatment of coronary artery disease than men, but gender differences in cerebrovascular disease have not been well studied. Our objective was to explore differences in the treatment of stroke between men and women. DESIGN: Secondary database analyses. STUDY PARTICIPANTS: We examined the use of carotid endarterectomy in a nationally representative sample of Medicare enrollees aged 65 to 84, hospitalized for a principal diagnosis of stroke in 1992, the “all strokes group”. We also studied a subgroup of patients, the “carotid disease subgroup”, admitted with a principal diagnosis of precerebral arterial occlusion and stenosis or transient cerebral ischemia. MEASUREMENTS: We determined rates of carotid endarterectomy for the all strokes group within gender and age groups and calculated corresponding female-to-male relative risks (RR) and 95% confidence intervals (CI). We also performed similar analyses for the carotid disease subgroup. We then used logistic regression to estimate the relative risk of use of carotid endarterectomy for women, controlling for age and comorbidity. RESULTS: The all-strokes group consisted of 3356 women and 2927 men, of whom 1009 women and 990 men were in the carotid disease subgroup. The overall age-adjusted female-to-male relative risk of undergoing carotid endarterectomy for those aged 65 to 84 was 0.69 (95% CI, 0.64-0.74) in the all strokes group and 0.77 (95% CI, 0.72-0.82) in the carotid disease subgroup. In both analyses, the RR became more pronounced with increasing age. In the all strokes group, for example, the RR was 0.80 (0.70-0.92) for those aged 65 to 69 and 0.39 (0.32-0.48) for those aged 80 to 84. The RR for the all strokes group remained similar in magnitude even after controlling for comorbidity (RR, 0.63 and 95% CI, 0.59-0.70). CONCLUSION: We conclude that women hospitalized for strokes undergo fewer carotid endarterectomies than men. Further studies are needed to examine the reasons for and implications of this gender difference. J Am Geriatr Soc 48:741–745, 2000.
Supporting mobile device communications in the presence of broadcast servers

Broadcast data dissemination is well-suited for mobile wireless environments, where bandwidth is scarce and mutual interference must be minimised. However, broadcasting monopolises the medium, precluding clients from performing any other communication. We address this problem in two ways. Firstly, we segment the server broadcast, with intervening periods of silence, during which the wireless devices may communicate. Secondly, we reduce the average access delay for clients using a novel cooperative caching scheme. Our scheme is fully decentralised and uses information available locally at the client. Our results show that our model prevents the server from monopolising the medium and that our caching strategy reduces client access delays significantly.
Competition between zonae pellucidae and a proteinase inhibitor for sperm binding.

Murine sperm bind a proteinase inhibitor of seminal vesicle origin at ejaculation. The inhibitor binds in the acrosomal region of the sperm head and is removed during in utero or in vitro incubation. Adding inhibitor to sperm reduces their ability to bind zonae, while adding the purified inhibitor binding site to cumulus-free, zona-intact oocytes reduces the ability of the oocytes to bind sperm. Immuno-aggregation of the inhibitor binding site results in exocytosis of the acrosome. These observations suggest that the inhibitor binding site may participate in zona binding and the acrosome reaction. If the inhibitor binding site binds both the zona and the seminal inhibitor, then these components should compete with each other for that site on the sperm. We show that purified seminal inhibitor, as well as other proteinase inhibitors, block zona-induced acrosome reactions. Likewise, zona glycopeptides block inhibitor/anti-inhibitor-induced acrosome reactions in a concentration-dependent fashion. The inhibitor! anti-inhibitor-induced acrosome reaction is sensitive to pertussis toxin and proteinase inhibitor and thus is similar to zona-induced reactions. These findings support the suggestion that the trypsin inhibitor binding site on the head of the sperm ftinctions to insure sperm-zona binding and induction of the acrosome reaction.
Critical Elements of an Internet Based Asynchronous Distance Education Course

Asynchronous distance education options are rapidly becoming attractive to a number of audiences for a variety of reasons. Unlike synchronous models, asynchronous courses do not require extensive technological or facilities support, they do not require laborious scheduling formulas or restrictive time commitments. They offer students freedom in choosing times and locations of engaging in the course, and can be conducted with hardware and software readily available to most students. The present article outlines some of the issues that need to be considered when developing an asynchronous distance course. It describes the components of a course currently being offered using this model, and concludes with a discussion of some problem areas that students and faculty may face when engaging in this new course format.
Heterologous Expression and Reconstitution of Fungal Mn Peroxidase

We have optimized the conditions under which recombinant Mn peroxidase from the white-rot fungus Phanerochaete chrysosporium can be expressed in Escherichia coli. A bacterial expression vector for the cDNA of Mn peroxidase isozyme H4 (lambda MP1) was constructed (R. E. Whitwam, I. G. Gazarian, and M. Tien, Biochem. Biophys. Res. Commun. 216, 1013-1017, 1995) whose expression in E. coli results in the formation of catalytically inactive polypeptide which can be refolded to active enzyme. The refolded enzyme was purified to homogeneity. Refolding was most efficient in 2 M urea, pH 8.0, and was absolutely dependent upon the presence of CaCl2, hemin, and oxidized glutathione. The recombinant enzyme had the same spectral and kinetic properties as the native fungal enzyme. The Km of recombinant Mn peroxidase for substrates H2O2 and the Mn2+/oxalate complex are 100 and 52 microM, respectively. The kcat as measured by Mn3+/oxalate formation is 450 s-1. These are essentially the same values as seen with the native fungal enzyme. The rate of formation of compound I, the two-electron-oxidized state of the enzyme, is 4.0 x 10(6) M-1 s-1, identical to the rate of the native fungal Mn peroxidase. The reaction of compound I with Mn2+ is too fast to measure at pH 4.5 in the recombinant Mn peroxidase. At a suboptimal pH of 2.5 a rate of 4.2 x 10(4) M-1 s-1 is obtained for the recombinant enzyme. The reaction of compound II, the one-electron-oxidized state of the enzyme, with Mn2+/oxalate has a Kd of 13 microM and a first-order rate constant of 230 s-1 in the recombinant enzyme. These rates are essentially the same as those seen with the native fungal MnP. These results demonstrate that the bacterial expression of recombinant Mn peroxidase is a convenient and efficient system for the expression and characterization of Mn peroxidase.
Radial nerve injury after routine peripheral vein cannulation

The dorso-radial aspect of the wrist and hand is a common location for intravenous (IV) cannulation prior to anesthesia. The sensory branch of the radial nerve lies superficially in this area, and it can be injured during routine insertion of IV catheters. In this case, the nerve was lacerated during insertion and a painful neuroma developed after elective surgery and anesthesia. Knowledge of this complication may help with its recognition and treatment.
Feeding and Insulin Increase Leptin Translation IMPORTANCE OF THE LEPTIN mRNA UNTRANSLATED REGIONS

The post-transcriptional mechanisms by which feeding and insulin increase leptin production are poorly understood. Starvation of 6–7-week-old rats for 14 h decreased leptin mRNA level by only 22% but decreased plasma levels, adipose tissue leptin content, and release by over 75%. The decreased leptin with starvation was explained by >85% decrease in relative rates of leptin biosynthesis measured by metabolic labeling and immunoprecipitation. In vitro insulin treatment of adipose tissue from fed or starved rats for 2 h increased relative rates of leptin biosynthesis by 2–3-fold, and the effect was blocked by inhibition of phosphatidylinositol 3-kinase or mammalian target of rapamycin. Consistent with the hypothesis that feeding/insulin increases leptin translation, more leptin mRNA was associated with polysomes in adipose tissue of fed than starved rats, and in vitro incubation of adipose tissue of starved rats with insulin shifted leptin mRNA into polysomes. To assess the mechanisms regulating leptin translation, chimeric human leptin untranslated region (UTR) reporter constructs were transiently transfected into differentiated 3T3-L1 adipocytes. The 5′-UTR of leptin mRNA increased luciferase reporter activity 2–3-fold, whereas the full-length 3′-UTR (nucleotides 1–2804) was inhibitory (–65%). Sequences between nucleotides 462 and 1130 of the leptin 3′-UTR conferred most of the inhibitory effect. Insulin stimulated the expression of constructs that included both the full-length 5′-UTR and the inhibitory 3′-UTR, and the effect was blocked by inhibition of phosphatidylinositol 3-kinase or mammalian target of rapamycin. Our data suggest that insulin derepresses leptin translation by a mechanism that requires both the 5′-UTR and the 3′-UTR and may contribute to the increase in leptin production with feeding.
Reaction rate calculations for cosubstrates diffusing into catalyst layer from opposite sides

The effects of diffusion on a reaction taking place in a permeable catalyst are examined theoretically for the case where the reaction has two substrates supplied from opposite sides of a catalytic slab. The solutions of the reaction–diffusion equation for combinations of zeroth-and first-order kinetics are given in terms of an effectiveness factor and a parameter describing the position in the layer where the reaction occurs. In these terms, the results vary only weakly with reaction order. The use of the exact solutions for a reaction that is zeroth order in both sub strates is proposed as a general rule for estimating the reaction rate and the reaction position.
New complex borides with ReB2- and Mo2IrB2-type structure

Abstract The compound V 0.4 Os 0.6 B 2 was found to crystallize with ReB 2 -type structure. V 2 OsB 2 , Mo 2 OsB 2 , and W 2 OsB 2 are isotypic with the crystal structure of Mo 2 IrB 2 . The crystal chemistry of complex borides with ReB 2 - and Mo 2 IrB 2 -type structure is discussed.
Management of periocular basal cell carcinoma: Mohs' micrographic surgery versus radiotherapy

In treating periocular basal cell carcinoma the goal is to achieve the most complete eradication of affected tissue while preserving as much healthy tissue as possible. In the first of these "Viewpoints" articles, Drs. Leshin and Yeatts discuss the success of Mohs' microsurgical technique (MMS) in both regards. Moreover, they note that MMS offers the additional advantage of placing all surgical and histological phases of tumor excision in the hands of one specialist, thus circumventing problems that may arise with procedures requiring the separate involvement of several specialists. In the second article, Drs. Anscher and Montana point out that modern radiotherapy techniques may offer adequate tumor control with less damage to surrounding tissues than is caused by surgical excision and reconstruction. With small lesions, radiotherapy has a success rate similar to that of surgery. With large lesions, the success rate is lower; however, if surgical excision would cause extensive disfigurement or functional damage, an initial trial of radiotherapy may be warranted, then followed by surgery, if necessary. In an editorial, Dr. Dutton summarizes the indications for and advantages and disadvantages of both techniques.
The role of cyclic AMP in the thermosensitive lesion of the formation of closed covalent circular Rts 1 DNA.

Abstract The formation of closed covalent circular DNA of R factor, Rts 1, does not take place at non-permissive temperature, 42°C, in E. coli 20SO. However, when Rts 1 was placed in mutants having a low level of cyclic AMP or lacking cyclic AMP receptor protein, the thermosensitive lesion is overcome. Addition of cyclic AMP caused inhibition of the formation of ccc DNA in mutants with low cyclic AMP level, but not in mutants lacking cyclic AMP receptor protein.
A practical guide to transmission electron microscopy of aerogels

Aerogel-based materials encompass an outstandingly diverse class of nanoscale single-phase and composite materials, from the traditional base-catalyzed silica aerogel with its branched-beaded network of amorphous mesoparticles to the novel composite aerogels incorporating self-assembled protein superstructures. The structural characterization of these disparate materials often requires more than routine application of basic transmission electron microscopy (TEM) techniques. This paper serves as a guide to the full utilization of TEM for investigating new aerogel architectures.
Interparental conflict and relations with parents as predictors of young adult functioning

Interparental conflict is a known risk factor for child adjustment problems; yet few studies have examined its long-term effects. This study tests the following hypotheses: Interparental conflict has both longitudinal and concurrent influences on the functioning of young adult children, and the relationship between young adults and their parents mediates these influences. We assessed a community sample (N = 243) of families when the target child was in early to middle adolescence. We then reassessed them 6 years later during young adulthood. The links of interparental conflict measured at the two time points to young adults' general psychopathology and antisocial behavior were examined using multiple regression analyses. The quality of the relationship between young adults and each parent was added to each equation as a potential mediating variable. Results showed that concurrent, but not earlier, interparental conflict predicted males' antisocial behavior. No support was found for the mediational model, but support was found for an alternate model positing direct effects for interparental conflict and the parent-young adult relationship on young adult functioning. For females and males, problematic relationships with mothers and father predicted greater general psychopathology, while problems in paternal relationships predicted higher levels of antisocial behavior only for females.
Inhibition of agrin‐mediated acetylcholine receptor clustering by utrophin C‐terminal peptides

Background: Agrin is an extracellular matrix protein that is required for neuromuscular synaptogenesis and is particularly important in the clustering of acetylcholine receptors at post-synaptic sites. Little is known about the signal transduction pathway of agrin-mediated receptor clustering, although cytoskeletal elements and a dystrophin associated glycoprotein complex (DGC) have been implicated. Because agrin binds to α-dystroglycan, a member of the DGC, and the DGC is linked to actin through utrophin at postsynaptic sites, it has been suggested that binding of utrophin to the DGC plays a central role in agrin mediated receptor clustering. Results: To test this hypothesis, we expressed at high levels the DGC binding domains of utrophin in cultured myotubes using recombinant Semliki Forest Virus. Myotubes expressing the utrophin and dystrophin DGC binding domain formed significantly fewer acetylcholine receptor clusters in response to agrin than myotubes expressing other proteins. Conclusions: These results suggest involvement of the DGC and utrophin in the signal transduction pathway of agrin-mediated acetylcholine receptor cluster formation or stabilization.
Septic arthritis of the knee: Complication of intra-arterial thrombolytic therapy

A case of septic arthritis of the knee complicating intra-arterial thrombolysis is reported. Septic complications following the use of intravascular catheters are usually relatively minor. This serious case and the discussion that arises highlights the need for shortening the duration of intravascular thrombolysis regimes.
ECONOMIC ANALYSIS IN THE MAINTENANCE, REPAIR, AND OVERHAUL INDUSTRY: AN OPTIONS APPROACH

This paper presents a practical case application of the real options framework to a multi-stage investment in the aerospace maintenance, repair, and overhaul (MRO) industry. With the deregulated commercial airline industry and military procurement reform, the $44 billion MRO sector must implement tools to remain strategically poised. In this case study, the MRO participant values a multi-stage irreversible expenditure in maintenance equipment and processes under air travel demand uncertainty using a real options analysis. The investment scenario is viewed from a delay, growth, and compound options framework, and an appropriate sensitivity analysis is performed. The main contribution of this paper is the detailed real option framing, valuation, and discussion that may be used as an illustration for industry practitioners or classroom instruction.
On random time and on the relation between wave and telegraph equations

Kac's conjecture relating the solution of wave and telegraph equations in higher dimensions through a Poisson-process-driven random time is established through the concepts of stochastic calculus. New expression is derived for the probability density function of the random time. We demonstrate how the relationship between the solution of a lossy wave- and that of a lossless wave equation can be exploited to derive some statistical identities. Relevance of the results presented to the study of pulse propagation in a dispersive medium characterized by a Lorentz or Drude model is discussed and new evolution equations for 2-D Maxwell's equations are presented for the Drude medium. It is shown that the computational time required for updating the electric field using the stochastic technique is expected to go up as O(√t).
Genetic polymorphisms and gene expression variations at enzyme loci in chinese hamster cell lines

A series of Chinese hamster cell lines commonly used in somatic cell genetics research was examined for variations in either expression or electrophoretic mobility of 43 enzyme gene products by starch gel electrophoresis followed by histochemical staining. Stable variations in the qualitative expressions of the creatine kinase B and adenylate kinase 1 (AK1) loci were detected among the cell lines and verified in subclones. All ten cell lines examined were deficient in the expression of the lactate dehydrogenase B locus. Polymorphisms were detected for the adenosine deaminase (ADA) and AK2 loci among the cell lines and shown to exist in a series of Chinese hamsters. Electrophoretic banding patterns from tissues, sublines, and subclones of the same genetic source and Hardy-Weinberg distribution of phenotypes from different genetic sources confirmed that the polymorphisms were based on its inheritance of two codominant autosomal ADA and AK2 alleles that specified electrophoretically variant enzymes.