cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of antisense inhibition of urokinase receptor on malignancy

Plasminogen activator of the urokinase type (uPA) has been shown to be overexpressed in most experimental malignant tumors and human cancers (Dano et al. 1985; DeBruin et al. 1987; Sappino et al. 1987; Markus 1988; Sim et al. 1988; Duffy et al. 1990; Janicke et al. 1990; Testa and Quigley 1990; Sappino et al. 1991; Mignatti and Rifkin 1993). The overproduction of uPA by tumor cells was detected in primary cultures, organ cultures, and cancer cell lines. However, examination by in situ analyses (both immunocytochemistry and in situ hybridization) of sections of human tumors consisting of multiple cell types identified in some instances cells other than cancer cells as the uPA producers. Depending on the type of cancer, and in some instances the laboratory and the reagents used to perform the analysis, tumor, stromal, and sometimes infiltrating macrophages were found to be the main source of uPA and/or its receptor (Grondahl-Hansen et al. 1991; Pyke et al. 1991, 1993; Bianchi et al. 1994; Carriero et al. 1994). Regardless of its source, however, it has been firmly established in several human cancers that high levels of uPA are predictive of more aggressive disease with shorter relapse-free survival (Duffy et al. 1990; Janicke et al. 1990, 1991; Grondahl-Hansen et al. 1993; Kobayashi et al. 1994).
Current Gaps in Understanding the Molecular Basis of FXTAS

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder with defining clinical features that include kinetic tremor, gait ataxia, and parkinsonism, with associated features spanning medical, cognitive, and psychiatric clinical domains. The emerging model for the pathogenesis of FXTAS is that of RNA toxicity as a consequence of the sequestration of RNA binding proteins by the expanded CGG-repeat element within the FMR1 message, thus compromising the normal functions of those proteins. A principal challenge at this point is to determine precisely which proteins are involved in FXTAS pathogenesis and how to prevent or reverse this process. A second challenge is to determine why there is incomplete penetrance of FXTAS among premutation carriers with identical CGG-repeat lengths, and what the protective factors are in some carriers. Finally, the discovery in premutation mice of early neurodevelopmental abnormalities, some occurring even during late embryogenesis, raises the question of whether FXTAS is the end-stage of a life-long process of neuronal dysregulation. If an extended pre-clinical phase precedes the development of FXTAS, there is great potential for therapeutic intervention, years or even decades before its clinical features are manifest.
Ecohydrological feedbacks between salt accumulation and vegetation dynamics: Role of vegetation‐groundwater interactions

[1] When plants are both sensitive to salt levels in the root zone and able to modify the soil salt balance, changes in vegetation cover may affect the local hydrologic conditions and favor the accumulation of salt within different parts of the soil profile. In such cases a salt-vegetation feedback may exist, whereby both a state with vegetation cover, deep water table, and low salinity and a state with sparse or no vegetation, shallow water table, and high salinity can be stable. In this paper, we develop a modeling framework to relate vegetation–soil salinity feedbacks to the emergence of multiple stable states in the underlying dynamics. This model is used to simulate various scenarios involving changes in forcing parameters of salinity-vegetation dynamics using data from the Murray-Darling Basin. Results show the presence of a strong feedback resulting in bistable dynamics for a wide range of environmental conditions, which has the effect of reducing the resilience of plant ecosystems and the productivity of agricultural systems for areas where such a feedback can occur.
Time mechanics as applied to event ordering

The notion of time is interpreted and quantified as a means to ensure consistent and accurate evaluations by time-relevant functions. As an integral part of a study encompassing all functions of automata, we formulate the process as it applies to event ordering. In developing this process, logical clocks are first examined to aid in defining the inter-relation between explicitly and implicitly related events. Understanding the extent to which logical clocks can be representative of system wide ordering, an ubiquitous measure is considered. We define "real time" as a means by which all measurement devices account for the same measure at the same moment, and whereby they remain consistent with respect to each other for the life of the system. "Real time" as an absolute and universally applicable system measure is analyzed and an algorithm for its implementation is proposed. With each event assigned a time value that is respected system wide, the application of mutual exclusion algorithms are presented and their behavior assessed when ordering certainty is ensured. Further, a means for maintaining consistent and accurate system wide time is developed.
Nutrition Education in U.S. Medical Schools: An Assessment of Nutrition Content in USMLE STEP Preparation Materials

In the U.S., the numbers of obese individuals and of obesity-related health conditions are rising. While physiciansunderstand the need to improve patient health by promoting a healthy lifestyle, the advancement of nutritioneducation in medical school and residency is not keeping pace. This is evident in the inadequate time dedicated tonutrition education by medical schools and in the dissatisfaction of medical students and residents with their medicalnutrition training.The aim of the current study was to investigate how food, diet, nutrition, and obesity are represented in the U.S.medical school licensing examinations (USMLE) as a potential incentive to better match medical nutrition curriculato the modern societal needs.We semi-quantitatively analyzed nutrition-related information of the USMLE Step 1, 2, and 3 Content Descriptiondocuments and two test preparation books, using QRS NVivo 10. The software’s coding comparison query was usedas reliability statistics. We found an adequate amount of nutrition references. However, the content of the referenceswas inadequate in that there was minimal information in regards to chronic diseases and no content related to diseaseprevention. Moreover, there was a lack of specifics in regards to food and nutritional science.We propose a content adjustment to the medical licensing exams to ensure that future physicians are more skilledand comfortable in fulfilling their roles as health care providers and advisors for an increasingly obese patientclientele.
Blood pressure and norepinephrine spillover during propranolol infusion in humans

To determine whether a reflex increase of sympathetic nervous system activity contributes to maintenance of blood pressure during acute beta-adrenergic blockade, we measured plasma norepinephrine levels and norepinephrine kinetics during propranolol administration. During a 90-min infusion of propranolol (10 mg iv + 80 micrograms/min) in 12 normal subjects, heart rate fell from 56 +/- 2 to 49 +/- 2 (SE) beats/min (P less than 0.001), but there was no fall in mean arterial blood pressure (84 +/- 3 mmHg before and 86 +/- 3 mmHg after propranolol). Arterial plasma norepinephrine levels rose from 183 +/- 20 to 250 +/- 29 pg/ml during propranolol (P less than 0.001), suggesting increased sympathetic vasoconstrictor tone. However, isotope dilution studies using tritiated norepinephrine infusion showed that arterial plasma levels of tritiated norepinephrine rose from 743 +/- 78 to 1,002 +/- 101 dpm/ml during propranolol (P less than 0.001), indicating a reduction in the rate of norepinephrine clearance from plasma. The calculated fall in clearance from 1.90 +/- 0.13 to 1.42 +/- 0.11 1/min (P less than 0.001) entirely accounted for the rise in plasma norepinephrine, since the calculated rate of norepinephrine spillover into plasma remained at the base-line level of 340 +/- 40 ng/min during propranolol. In control studies on four subjects, arterial plasma norepinephrine levels and norepinephrine kinetics did not change from base line during the control period. We conclude that maintenance of blood pressure during propranolol infusion is not due to a reflex generalized increase of sympathetic vasoconstrictor tone.
Conformation of the regulatory domain of cardiac muscle troponin C in its complex with cardiac troponin I.

Calcium activation of fast striated muscle results from an opening of the regulatory N-terminal domain of fast skeletal troponin C (fsTnC), and a substantial exposure of a hydrophobic patch, essential for Ca(2+)-dependent interaction with fast skeletal troponin I (fsTnI). This interaction is obligatory to relieve the inhibition of strong, force-generating actin-myosin interactions. We have determined intersite distances in the N-terminal domain of cardiac TnC (cTnC) by fluorescence resonance energy transfer measurements and found negligible increases in these distances when the single regulatory site is saturated with Ca(2+). However, in the presence of bound cardiac TnI (cTnI), activator Ca(2+) induces significant increases in the distances and a substantial opening of the N-domain. This open conformation within the cTnC.cTnI complex has properties favorable for the Ca(2+)-induced interaction with an additional segment of cTnI. Thus, the binding of cTnI to cTnC is a prerequisite to achieve a Ca(2+)-induced open N-domain similar to that previously observed in fsTnC with no bound fsTnI. This role of cardiac TnI has not been previously recognized. Our results also indicate that structural information derived from a single protein may not be sufficient for inference of a structure/function relationship.
Incidence and Mortality Rates of Syncope in the United States

Abstract Purpose Syncope is a common cause of hospitalization in the US. The main objective of this study is to determine the incidence and mortality rates when patients are admitted with a principle diagnosis of syncope. Methods An observational cross-sectional study included patients with the principle diagnosis of syncope identified from the National Inpatient Sample database for the years 2000-2005. Incidence rate of syncope was adjusted according to the US Census data. In-hospital mortality and its predictors were identified by a logistic regression analysis, and Cochran-Armitage test was used for trend analysis. Results After data cleansing, 305,932 patients were included in the analysis. Adjusted incidence rate of syncope varied between 0.80 and 0.93 per 1000 person-years and was unchanged over the years included in the analysis. Overall mortality rate is 0.28%, a trend that has not changed over the years ( P =0.07). The odds ratio (OR) of death increased with age, becoming more prominent after age 40 years. Hospital mortality is higher in men (OR 1.49; 95% confidence interval [CI], 1.30-1.71) and in patients with higher comorbidity index (OR 1.39; 95% CI, 1.20-1.62) for moderate, and (OR 4.14; 95% CI, 3.05-5.61) for severe comorbidity index. The median cost of hospitalization is $8579, which increased by 3- to 11-fold if patients had a cardiac pacemaker or implantable cardioverter-defibrillator. Conclusions Syncope remains a common cause of hospital admission. The hospital mortality rate for syncope is low. A better definition and a nationally implemented care path for syncope diagnosis could provide a substantial cost savings.
High-magnetic-field phase diagram of a quasi-one-dimensional metal

We report the high magnetic-field phase (to 45 T) of the quasi-one-dimensional organic conductor $(\mathrm{TMTSF}{)}_{2}{\mathrm{ClO}}_{4}$ in its thermally quenched phase. Termed $``\mathrm{Q}\ensuremath{-}{\mathrm{ClO}}_{4},''$ this phase exhibits a spin-density-wave (SDW) transition at $\ensuremath{\approx}5 \mathrm{K}$ which is strongly magnetic-field dependent, and distinct from the phase extensively studied in the annealed material. The field dependence of the SDW transition is well modeled by the theoretical treatment of Bjelis and Maki. We discuss the $B\ensuremath{-}T$ phase diagram of $\mathrm{Q}\ensuremath{-}{\mathrm{ClO}}_{4}$ in the context of the hierarchy of low-dimensional organic metals (one-dimensional towards two-dimensional), and describe the temperature dependence of the quantum oscillations observed in the SDW phase.
Changes in sleep-wakefulness in female rats during circadian and estrous cycles.

Abstract Continuous EEG records from chronically implanted cerebral electrodes have been made of sleep-wakefulness in 5 female rats throughout their 4-day or 5-day estrous cycles, under controlled lighting conditions with 14 h light and 10 h darkness per day. Percentages of alertness, slow wave sleep (SS) and paradoxical sleep (PS) in each 10-min period were punched on IBM cards and introduced to a computer system capable of plotting these percentages daily in each rat and averaging across animals for each time period on corresponding days of the estrous cycle. The results reveal rapid shifts from relative alertness to sleep after the lights come on in the morning. Highest levels of alertness generally occur during the early evening and PS during the afternoon, including the afternoon of proestrus. The day of vaginal cornification (‘estrus’) shows a high percentage of PS — after a night characterized by alertness and virtual absence of PS,i.e., the night of behavioral estrus and ovulation. The female rat, like the male, sleeps on the average about two-thirds of the daylight hours and only one-third of the dark period. Hormonal changes during the day of proestrus appear to increase alertness that night, compensated by an increase in sleep, especially PS, the following day.
Our microbial selves: what ecology can teach us

Advances in DNA sequencing have allowed us to characterize microbial communities—including those associated with the human body—at a broader range of spatial and temporal scales than ever before. We can now answer fundamental questions that were pre­ viously inaccessible and use well­tested ecological theories to gain insight into changes in the microbiome that are associated with normal development and human disease. Perhaps un surprisingly, the ecosystems associated with our body follow trends identi­ fied in communities at other sites and scales, and thus studies of the microbiome benefit from ecological insight. Here, we assess human microbiome research in the context of ecological principles and models, focusing on diversity, biological drivers of community structure, spatial patterning and temporal dynamics, and suggest key directions for future research that will bring us closer to the goal of building predictive models for personalized medicine.
Tricarbonyltris(pyridine)molybdenum: A Convenient Reagent for the Preparation of (π-Allyl)molybdenum Complexes

The reaction of tricarbonyltris(pyridine)molybdenum(0) with various allylic substrates provides easy access to the corresponding (π-allyl)molybdenum(II) complexes in high yields under variable conditions.
Gender Differences in Reported AIDS-Indicative Diagnoses

To compare AIDS-defining conditions in women and men, US adult AIDS cases diagnosed between January 1988 and June 1991 and reported to the Centers for Disease Control and Prevention through June 1992 were examined. For most AIDS-defining conditions, the prevalence was similar for women and men when differences in race/ethnicity and mode of transmission were accounted for. Pneumocystis carinii pneumonia was the most prevalent condition (> 50%) regardless of gender, race/ethnicity, or mode of transmission. By logistic regression analysis, among injection drug users, conditions reported significantly more frequently in women than in men include esophageal candidiasis (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.40-1.62), herpes simplex virus (HSV) disease (OR, 1.68; CI, 1.46-1.94), and cytomegalovirus (CMV) disease (OR, 1.43; CI, 1.18-1.73). More knowledge of the interrelationships in women between HIV infection and secondary opportunistic infections, including candidiasis and sexually transmitted disease (e.g., HSV and CMV) is needed.
Cryptic post-depositional reworking in aeolian sediments revealed by the anisotropy of magnetic susceptibility

Abstract Our anisotropy of magnetic susceptibility (AMS) investigation of the Gold Hill Steps (GHS2) and Halfway House (HH3) loess and paleosol profiles in central Alaska confirms that post-depositional reworking of loess at Gold Hill Steps has taken place and, of greater importance, identifies the reworked depth intervals. In GHS2, the majority of the loess below 7.80 m depth has been reworked. The loess at the Halfway House site is, as stated in the literature, a predominantly undisturbed aeolian deposit. However, we have identified two intervals that have been reworked in HH3. We infer from the depth variation of the AMS orientation distribution at GHS2 that the presence of permafrost in the past was the dominant active mechanism producing the observed deformations. Permafrost loess behaved (1) as impermeable layers focusing and channeling flow, most likely that of groundwater, and (2) as rigid bodies undergoing rotations and lateral translations. A modern analogue of focused flow by an impermeable layer is identified at HH3.
Gain squaring in a Cr:Nd:GSGG active-mirror amplifier using a cholesteric liquid crystal mirror

The small-signal gain of a Cr:Nd:GSGG active-mirror amplifier has been squared using a passive, 10- mu m-thick, cholesteric liquid-crystal selective reflection mirror. This double/double-pass configuration was easy to align and solved difficulties, such as polarization leakage and back-reflection coupling, which had plagued previous multipass schemes. The mechanism for this gain squaring is explained in terms of the optical properties of cholesteric liquid crystals. >
The cross-cultural transfer of educational technology: A myth

Abstract This paper argues that technologies can never be transferred from one culture to another. The implementation by Costa Rica of the Open University system of technologies developed in England is used as a case in point. The paper focuses on the non-applicability of using the term “transfer” with its attendant connotations, to signify the implementation of similar technologies in different cultures; differentiates between system specific and culture specific problems in the process of this implementation: and discusses the interaction of three cultures in the process of “transferring” a system of technologies from one of these cultures to another. The Open University system of technologies is described as it exists in England and the system specific problems of these technologies are delimited. The system of technologies is then “transferred” to Costa Rica and the culture specific problems discussed as seen by two evaluators from yet a third culture (the United States). The expectations of individuals from all three cultures (English, Costa Rican and U.S.) are raised in tight of these culture specific problems.
Metal corrosion studies with the fluorosulphonic acid–antimony pentafluoride superacid system

Abstract Because of their rapid dissolution of many actinide metals and refractory oxides, superacids such as HSO 3 F/SbF 5 have potential applications in actinide processing. However, material compatibility must first be addressed because of the highly corrosive nature of superacids. This paper describes the qualitative rates of attack of fluorosulphonic acid–antimony pentafluoride superacid on a variety of metal substrates relevant to nuclear processing.
Intermolecular V(D)J recombination is prohibited specifically at the joining step.

Abstract V(D)J recombination, normally an intramolecular process, assembles immunoglobulin and T cell receptor genes from V, D, and J coding segments. Oncogenic chromosome translocations can result from aberrant rearrangements, such as occur in intermolecular V(D)J recombination. How this is normally prevented remains unclear; DNA cleavage, joining, or both could be impaired when the recombination signal sequences (RSS) are located in trans , on separate DNA molecules. Here, we show that both trans cleavage and joining of signal ends occur efficiently in vivo. Unexpectedly, trans joining of coding ends is severely impaired (100- to 1000-fold), indicating that protection against intermolecular V(D)J recombination is established at the joining step. These findings suggest a novel surveillance mechanism for eliminating cells containing aberrant V(D)J rearrangements.
Modeling breast cancer in vivo and ex vivo reveals an essential role of Pin1 in tumorigenesis

Phosphorylation on certain Ser/Thr-Pro motifs is a major oncogenic mechanism. The conformation and function of phosphorylated Ser/Thr-Pro motifs are further regulated by the prolyl isomerase Pin1. Pin1 is prevalently overexpressed in human cancers and implicated in oncogenesis. However, the role of Pin1 in oncogenesis in vivo is not known. We have shown that Pin1 ablation is highly effective in preventing oncogenic Neu or Ras from inducing cyclin D1 and breast cancer in mice, although it neither affects transgene expression nor mammary gland development. Moreover, we have developed an ex vivo assay to uncover that a significant fraction of primary mammary epithelial cells from Neu or Ras mice display various malignant properties long before they develop tumors in vivo. Importantly, these early transformed properties are effectively suppressed by Pin1 deletion, which can be fully rescued by overexpression of cyclin D1. Thus, Pin1 is essential for tumorigenesis and is an attractive anticancer target. Our ex vivo assay can be used to study early events of breast cancer development in genetically predisposed mice.
Dynamic analysis and optimal feedback control synthesis applied to biological waste treatment

Abstract The dynamics and optimal feedback control of biological waste treatment processes are examined. Modern feedback control theory is applied and results are obtained for both proportional and proportional plus integral control. A dynamic mathematical model of the system is developed by employing a Monod kinetic model, which is modified to account for endogenous metabolism, and a complete mixing flow model in the growth chamber. The feedback control is implemented via the flow rate so as to maintain desired effluent concentrations. External disturbances which cause changes in substrate concentration and/or cell concentration are considered and optimal control effort is applied. Results are also presented for impulse and step changes in the influent substrate concentration. It is found that by changing the values of the weighting factors in the objective function, it is possible to obtain good control of either the effluent substrate concentration or cell concentration.
Characterization, Localization, and Biosynthesis of an Interstitial Retinol‐Binding Glycoprotein in the Human Eye

Human eyes contain an Mr 135K retinol-binding protein that is analogous to interstitial retinol-binding protein ( IRBP ) in the subretinal space of bovine eyes. It is a glycoprotein, because it binds 125I-concanavalin A, 125I-wheat germ agglutinin and 125I-Lens culinaris hemagglutinin. It does not bind Ricinus communis agglutinin I. After desialation, it binds Ricinus communis agglutinin I, but loses its capacity to bind wheat germ agglutinin. These observations, coupled with the known specificities of these lectins, suggest that at least one of the oligosaccharide chains is a sialated , biantennary complex type containing fucose. Both by direct analysis of dissected ocular tissues and by immunocytochemistry it was shown that human interstitial retinol binding protein is an extracellular protein that is confined predominantly to the subretinal space. Monkey retinas incubated in vitro in medium containing [3H]leucine were shown to synthesize and secrete this protein into the medium, a conclusion that was confirmed by immunoprecipitation with an immunoglobulin fraction prepared from rabbit antibovine IRBP serum. Virtually no other labeled proteins were detectable in the medium. It is concluded that interstitial retinol-binding protein meets many of the requirements for a putative transport protein implicated in the transfer of retinol between the pigment epithelium and retina during the visual cycle, and that the neural retina may play an important role in regulating its amount in the subretinal space.
Order effect of acoustic segments of VC and CV syllables on stop and vowel identification.

The purpose of this study was to determine the importance of the vocalic transition relative to other acoustic cues in the perception of both CV and VC syllables. Subjects identified stops, /p, t, ...
International Journal of STEM Education - a platform to promote STEM education and research worldwide

The International Journal of STEM Education is an online open-access journal that focuses on the study of learning and teaching in science, technology, engineering, and mathematics (STEM). It is being established as a brand new, forward looking journal that will add the multidisciplinary perspectives needed to complement current disciplinary-focused journals in the field of STEM education. As a peer-reviewed journal, it is positioned to promote original, systematic, and high-quality research and program development in the rapidly evolving, multidisciplinary, and global field of STEM education. The emerging field of STEM education presents a fascinating opportunity. At the policy level, providing high-quality STEM education has been recognized as critical for a nation’s prosperity and security around the world, including developing as well as developed countries. For example, US President Obama’s Reform for the Future agenda (see http://www.whitehouse.gov/ issues/education/reform) highlights the needs for (1) Race to the Top, (2) redesigning and reforming No Child Left Behind, (3) fortifying science, technology, engineering and math (STEM) education, (4) sparking innovation, (5) ensuring opportunity for all, and (6) strengthening the teaching profession. Strengthening STEM education is clearly taken as a priority. Similar national agendas can be found in many other countries. The commitment to promote and improve STEM education goes well beyond words, as evidenced by consistent and strong funding support. In the USA, the federal government spends nearly $3 billion on STEM education programs annually. Private funding also supports STEM education with an additional US$1 billion each year. The ever-increasing interests and research are also evidenced in the active development of numerous professional organizations and conferences related to STEM education. However, scholarly publication venues in the field of STEM education are limited,
In-situ chamber clean for chromium etch application

ABSTRACT As technology advances with feature size shrinking for the state-of-the-art integrated circuit (IC) fabrication, the degree of reduction in critical dimension (CD) features on a photomask shrinks at a faster pace, thanks to the ever aggressive optical proximity correction (OPC) design. In addition to stri ngent CD requirement, defect control has also become one of the most difficult challenges for advanc ed photomask manufacturing as a result of reduction in printable defect size. Therefore, keeping a photomask etching chamber at an optimal condition becomes very critical for controlling in both defectivity and CD fidelity. In the present study, analyses on optical emission spect rum (OES) collected in an Applied Materials Tetra TM chrome etch module have been performed to understand (1) the impact of Cr etching on the chamber condition, and (2) the effectiveness of in-situ chamber dry clean for chamber conditio n control and potential particle reduction. Results showed that, with the right selection of chamber materials (to be compatible with process chemistry and etching condition), the main impact of Cr etching on chamber condition and particle performance is from resist etch-by-products. Various plasma dry clean chemistries have been explored to address the effectiveness for the removal of such etch-by-products. As a result, an in-situ chamber clean (ICC) procedure is de veloped and has been validated to be production-worthy for desired particle control and chamber stability control. Keywords : Mask Etch, Dry clean, in-situ cham ber clean, defect, particle control
All Too Human: An Application of Nietzsche's Philosophy to the Counseling Profession

Friedrich Nietzsche's genealogical method offers an investigative tool for exploring value-laden language in the counseling profession. The genealogical method helps to identify evaluative terms, uncover implicit assumptions, and open possibilities for creative metaphors. The author demonstrates the genealogical method and explores implications for counseling practice and future research.
Synergy of Penicillin-Netilmicin Combinations Against Enterococci Including Strains Highly Resistant to Streptomycin or Kanamycin

combinations. Thissynergy withpenicillin could bedemonstrated ataconcentration of s7gg/ml foreither netilmicin orsisomicin. Studies onthekinetics ofkilling produced bythese combinations showed therateandextent ofkilling tobe directly dependent upontheorganism's relative susceptibility totheaminoglycoside alone andtheaminoglycoside concentration inthecombination. Results also indicated thattheinteraction between penicillin andnetilmicin wastrue synergy; i.e., rapid andcomplete killing wasproduced bycombinations containingeachdrugatconcentrations insufficient toproduce anykilling alone, andthe killing observed could notbeproduced byeither drugalone ataconcentration equivalent tothetotal dtugconcentration inthecombination. Thepotential clinical application ofthis synergistic interaction should beinvestigated further, especially inviewofrecent reports showing netilmicin tobeconsiderably less toxic thangentamicin inexperimental animals.
Model-based analysis of polymer drag reduction in a turbulent channel flow

We develop a model-based approach for studying the influence of polymers on drag reduction in a turbulent channel flow. Our simulation-free method utilizes turbulence modeling in conjunction with the analysis of stochastically forced linearized equations to capture the effect of velocity and polymer stress fluctuations on the turbulent viscosity and drag. We demonstrate that the essential drag-reducing trends observed in high-fidelity numerical simulations are captured by our approach.
Classical approach to quantum theory

A formulation of nonrelativistic, spinless, quantum mechanics is presented which is based on four postulates. Three of the postulates are very analogous to relations that hold in an operator formulation of classical mechanics, and the fourth is that the wave function evolves linearly in time. The conventional statistical assertions of quantum theory as well as the Schrodinger equation are recovered.
Autopsy: Moribund Art or Vital Science?

The autopsy rate in the United States has fallen dramatically in the past 40 years. Factors contributing to its decline include diagnostic over-confidence among clinicians, competing demands upon pathologists, difficulties obtaining consent from families, and its costs. The benefits of autopsy are clear: confirmation, clarification, and correction of antemortem diagnoses; discovery and definition of new diseases; evaluation of new diagnostic tests, new surgical techniques, and new drugs; investigation of environmental and occupational diseases; reassurance of family members; and contributions to medical and epidemiologic research. Proposals to revive the autopsy are reviewed, including altering the method of obtaining consent, altering autopsy procedures, structuring teaching around the autopsy, training autopsy pathologists in anatomic subspecialties, reinstating minimal autopsy requirements for hospital accreditation, providing financial support, and educating the public and the medical profession about its values. Accomplishing these changes quickly will prevent loss of its many benefits to the clinician, family, hospital, and society.
Acoustic receptivity of Mach 4.5 boundary layer with leading-edge bluntness

Boundary layer receptivity to two-dimensional slow and fast acoustic waves is investigated by solving Navier–Stokes equations for Mach 4.5 flow over a flat plate with a finite-thickness leading edge. Higher order spatial and temporal schemes are employed to obtain the solution whereby the flat-plate leading edge region is resolved by providing a sufficiently refined grid. The results show that the instability waves are generated in the leading edge region and that the boundary-layer is much more receptive to slow acoustic waves (by almost a factor of 20) as compared to the fast waves. Hence, this leading-edge receptivity mechanism is expected to be more relevant in the transition process for high Mach number flows where second mode instability is dominant. Computations are performed to investigate the effect of leading-edge thickness and it is found that bluntness tends to stabilize the boundary layer. Furthermore, the relative significance of fast acoustic waves is enhanced in the presence of bluntness. The effect of acoustic wave incidence angle is also studied and it is found that the receptivity of the boundary layer on the ‘windward’ side (with respect to the acoustic forcing) decreases by more than a factor of four when the incidence angle is increased from 0° to 45°. However, the receptivity coefficient for the ‘leeward’ side is found to vary relatively weakly with the incidence angle.
Octadecadienoic acids in the skin surface lipids of acne patients and normal subjects.

Measurements were made of the proportions of octadeca-5,8-dienoic acid and octadeca-9,12-dienoic acid in the scalp surface lipids of 6 normal subjects, 5 subjects with slight acne, and 9 subjects with severe acne. The group averages for the Δ5,8 isomer were: 0.74, 0.85, and 0.61% and for the Δ9.12 isomer were 0.56, 0.27, and 0.19%, respectively. The differences in the levels of the Δ9.12 isomer between the normal subjects and the groups with slight and with severe acne were statistically significant (p
Platinum(II) and Platinum(IV) Acyl and Formyl Complexes

An unprecedented monomeric platinum(IV) formyl complex has been prepared by analogy to the synthetic route used to form platinum(IV) acyl complexes.
Designing Surface-Mounted Components for High Reliability

Recent emphasis of the Department of Defense (DOD) on the reliability and integrity of avionics has spurred a new wave of research on this subject. This paper presents the results of a parametric investigation conducted to study the effect of vibration direction, boundary conditions, stiffeners and/or point supports, lead type, lead height, and the layout of the components on the natural frequencies and stresses exerted on a typical printed circuit board (PCB) used in avionics. The “robust design” procedure was adopted using a series of computer-simulated experiments. A finite element software, EMRC-FEAP, was utilized to estimate the maximum von Mises stresses within the critical leads, while the statistical analysis system (SAS) software was employed to analyze the natural frequency responses of the system and the signal-to-noise ratio (SNR) of the stresses induced at critical leads.
Fluorescence Signal Kinetics of a New Ca2+ Probebound to Cardiac Ryanodine Receptors Point to Micro-Domain Detection of Ca2+

To probe the micro-domains of Ca2+-signaling, we constructed a probe, calstabi-cam, targeted to cardiac ryanodine receptors (RyR2) by FKBP12.6 (calstabin 2) incorporating calmodulin and EYFP as Ca2+-sensor. 48-72h after infection of cultured rat neonatal cardiomyocytes (rNCM), global measurements of calstabi-cam fluorescence were accompanied by simultaneous recordings of Ca2+ channel (ICa) and Na+/Ca2+-exchanger (INCX) and compared to measurements of fluo-4 Ca-transients. rNCMs continued spontaneous beating after dialysis with Cs+-based internal solutions (0.1-0.2mM EGTA at −50mV) as they generated calstabi-cam fluorescence signals that coincided with INCX oscillations, like those measured by fluo-4 that were blocked by 10µM ryanodine. Activation of ICa (∼5pA/pF) triggered slowly relaxing Ca-transients of calstabi-cam fluorescence (ΔF/F0 = −0.11; n=14). Similarly, short caffeine pulses also activated long lasting calstabi-cam signals (-ΔF/F0=0.15±0.012; n=28) accompanied by INCX (1.57±0.13pA/pF; n=28). Calstabi-cam signals activated by rapid Na+ withdrawal was significantly delayed (∼230ms) compared to those triggered by ICa (∼13ms) or caffeine (∼35ms). Similar results were found in feline adult cardiac myocytes where 1µM Isoproterenol increased ICa significantly without enhancing the associated calstabi-cam transients. These results suggest that the new probe responds more effectively to Ca2+ that is released into dyadic clefts by RyR2 than by sarcolemmal Ca2+ influx via Na/Ca exchanger. The extremely slow decay kinetics of Calstabi-cam signal is consistent with the notion that [Ca2+] in the dyadic cleft may rise to much higher values than those of cytosol.
Construction of a dominant selectable marker using a novel dihydrofolate reductase.

Simian virus 40 promoter-enhancer-based mammalian expression plasmids using dihydrofolate reductase (DHFR)-encoding cDNA sequences originally isolated from two methotrexate (MTX)-resistant, DHFR-overproducing Chinese hamster lung cell lines were constructed. One, designated pSVA75, contains a DHFR cDNA that encodes leucine (Leu22) and corresponds to the wild type (wt), MTX-sensitive form of the enzyme [Melera et al., J. Biol. Chem. 263 (1988) 1978-1990]. The other plasmid, pSVA3, contains a cDNA that encodes a novel mutant form of the enzyme in which Leu22 has been changed to Phe [Melera et al., Mol. Cell Biol. 4 (1984) 38-48]. The resulting DHFR displays a 20-fold-enhanced resistance to inhibition by MTX, but maintains the catalytic activity of the wt enzyme [Albrecht et al., Cancer Res. 32 (1972) 1539-1546]. Transfection of DHFR- Chinese hamster ovary cells with either plasmid demonstrated that both were able to reconstitute the DHFR+ phenotype with equal efficiency (i.e., greater than 2.5 x 10(-3), indicating that both the wt and mutant enzymes were catalytically active in transfected cells. In addition, the mutant form of the enzyme was found to act as a dominant selectable marker when transfected into diploid DHFR+ cells, and to allow selection of resistant clones at low MTX concentrations (125 nM MTX) with a frequency of greater than 8 x 10(-4). Moreover, transfected clones were found to amplify their exogenous DHFR sequences to reasonably high levels (42-fold) at relatively low (888 nM) MTX concentrations, suggesting that substantial amplification of DHFR DNA and cotransfected sequences as well, can be achieved with this vector.
Vasovagal Syncope and Skeletal Muscle Vasodilatation: The Continuing Conundrum

During vasovagal syncope, profound bradycardia and hypotension occur. Atropine administration can prevent the bradycardia but not the hypotension, suggesting that marked peripheral vasodilation is a major cause of the fall in arterial pressure. This concept has been confirmed since vasovagal syncope can be seen in patients who have undergone heart transplantation and also in patients subject to cardiac pacing. In both cases, there is no bradycardia but hypotension during the syncopal attacks. The major site of the vasodilation is in skeletal muscle and muscle sympathetic nerve activity is suppressed just prior to and during vasovagal attacks, indicating that sympathetic withdrawal contributes to the dilation. However, the skeletal muscle vasodilation seen during syncope is greater than that caused by sympathetic withdrawal alone, and it is absent in limbs that have undergone surgical sympathectomy, or local anesthetic nerve block. These observations suggest a role for neurally mediated "active" vasodilation during syncope. The afferent neural pathways that evoke the profound vasodilation during vasovagal attacks remain the subject of debate. The neural pathways responsible for the active component of the dilation are also unknown. Recent evidence has demonstrated that cholinergic, beta-adrenergic, and nitroxidergic (nitric oxide) vasodilator mechanisms are not essential to observe the dilation, demonstrating that the mechanisms responsible for it remain a continuing conundrum.
Effects of heavy metals on alpha-fetoprotein in maternal sera and amniotic fluid of pregnant mice.

Abstract This report describes the effects of low levels of copper, nickel and lead salts on the concentrations of α-fetoprotein (AFP) in the sera and amniotic fluid of pregnant Nylar mice. During the early and mid-gestation (9–17 days), pregnant mice were injected intraperitoneally twice with heavy-metal salt solutions and were autopsied two days following the second injection. Maternal sera and amniotic fluid (AF) were collected and AFP levels were quantified by radial immunodiffusion. Metal levels determined by X-ray fluorescence spectroscopy in individual samples confirmed the presence of trace metals in the fetus. Low doses of nickel and copper were associated with elevated AFP levels in amniotic fluid in 15–17 day pregnant animals, while maternal serum AFP levels mostly remained unchanged. Decreased concentrations of maternal serum AFP occurred with increased doses of copper and lead in contrast to elevated concentrations of AFP in amniotic fluid. Futhermore, there was an increase in fetal wastage when higher doses of copper and lead were administered. A reduction of secondary litter size (F 1 generation) with low dosage levels of lead was also observed. These results imply that the fetal-maternal transfer of AFP may either be impaired or reflect increased leakage or decreased placental permeability in the presence of sublethal doses of copper and lead. These findings suggest that the parallel measurements of AFP concentrations in sera and amniotic fluid might be employed for assessment of embryo- and fetotoxicity when heavy metal intake is suspected during pregnancy.
Parallel Truth-Table Look-Up Digital Holographic Processing

Optical systems capable of performing arithmetic operations in parallel on arrays of binary input data are discussed. Data obtained from the truth-tables for the implemented operations are stored as holograms used in the systems. These data (or their reduced form) correspond to either the sum of products or the product of sums logical expressions relating each of the bits of the result to the input bits. Using the operations of addition and multiplication as examples it is shown that the number of holograms that must be recorded is considerably reduced when the input and output data are in binary-coded residue representation rather than in direct binary representation.
The Ancient Near East and Islam: The case of lot-casting

This article is a contribution to the question how far there was continuity between ancient Near Eastern and Islamic culture. It focuses on the practice of using lot-casting to allocate inheritance shares, conquered land, and official functions, and briefly surveys the history of this practice from ancient through Hellenistic to pre-Islamic times in order to examine its Islamic forms as reflected in historical and legal sources. It is argued that the evidence does suggest continuity between the ancient and the Islamic Near East, above all in the first century of the hijra, but also long thereafter, if only at a fairly low level of juristic interest. The article concludes with some general consideration of the problems involved in the study of the two disconnected periods of Near Eastern history.
Video modelling to educate patients.

Video modelling to educate patients Background. Changes in health care delivery in the United States of America due to economic pressures have required nurses to develop innovative instructional materials for educating patients and families. Educational materials such as videotapes, specifically designed to provide information and promote active participation in treatment decisions, can be effective tools for empowering patients. A comprehensive analysis in 1988 concluded that the concept of ‘video modelling’ or ‘behavioural modelling’ offered the greatest benefit of videotaped presentations. Aim of the study. The purpose of this integrative literature review was to examine the concept of video modelling and its applications in clinical practice. Methods. A computer search of the electronic databases of Medline and CINHAL between 1990 and 1999 produced a total of 40 research studies on video instruction for patients. Based on criteria for inclusion, 18 research studies involving video modelling were reviewed and three major uses were identified: (1) assisting decision making regarding treatment options; (2) reducing pre-procedural anxiety and improving coping skills; and (3) teaching self-care practices. Results. The studies reviewed included a variety of research designs, clinical settings, and patient populations. Despite these differences, several benefits to the use of video modelling were found. Patients who viewed videotapes regarding treatment options had a greater understanding of the risks and benefits of those choices and were more apt to be active participants in decision making. Collective results of the studies focusing on stress and coping revealed that preparatory videotapes using video modelling could have a positive effect on reducing anxiety and physiological arousal during stressful procedures. With self-care practices, several of the studies found that there was an increase in desired behaviours in people whose educational programmes included video modelling. Conclusions. The use of video modelling has potential benefits for clinical practice in facilitating knowledge acquisition, reducing preparatory anxiety, and improving self-care. Nurses must become more actively involved in evaluating various teaching approaches used with patients to enhance practice and outcomes.