cssi/SciSciGPT-SciSciNet huggingface dataset:
Fast photoinduced electron transfer through DNA intercalation

Abstract We report evidence for fast photoinduced electron transfer mediated by the DNA helix that requires metal complexes that are avid intercalators of DNA. Here the donor bis(phenanthroline)(dipyridophenazine)ruthenium(II) [Ru(phen)2dppz2+] and acceptor bis(9,10-phenanthrenequinone diimine)(phenanthroline)rhodium(III) [Rh(phi)2phen3+] intercalate into DNA with Kb > 10(6) M-1. Luminescence quenching experiments in the presence of two different lengths of DNA yield upward-curving Stern-Volmer plots and the loss of luminescence intensity far exceeds the change in emission lifetimes. In the presence of a nonintercalative electron acceptor, Ru(NH3)3+(6), Ru(phen)2dppz2+ luminescence is quenched much less efficiently compared to that found for the intercalative Rh(phi)2phen3+ quencher and follows linear Stern-Volmer kinetics; steady-state and time-resolved Stern-Volmer plots are comparable in scale. These experiments are consistent with a model involving fast long-range electron transfer between intercalators through the DNA helix.
Myocardial infarction in the absence of coronary arteriosclerosis: Result of coronary spasm (?)

Abstract An acute inferior wall myocardial infarction apparently resulted from a severe spasm of the left circumflex artery during selective coronary arteriography in a 52 year old woman who had a normal coronary arteriogram on a subsequent examination. Some of the possible mechanisms of production of myocardial infarction without arteriographic obstruction are discussed, such as coronary embolism or recanalization of a thrombus. It is believed that myocardial infarction without evidence of obstructive coronary disease may be caused by coronary spasm.
Shortcomings/strengths of specific sexual function questionnaires currently used in urogynecology: a literature review.

Pelvic floor disorders are common and although not life-threatening, have a significant impact on a patient’s quality of life. Sexual health is an essential component of a women’s overall well-being. In clinical practice and research it is important that the symptoms and impact of these disorders are assessed in an objective fashion. The most valid instruments to measure the presence, severity, and impact of a patient’s pelvic floor symptoms on function and quality of life are sexual function questionnaires. Sexual function questionnaires range from ad hoc questionnaires to condition-specific validated measures. This review article will describe the shortcomings and strengths of a variety of validated sexual function questionnaires currently used to measure sexual function in women with pelvic floor disorders.
Loop-erased self-avoiding random walk in two and three dimensions

IfŜ(n) is the position of the self-avoiding random walk in ℤ d obtained by erasing loops from simple random walk, then it is proved that the mean square displacementE(¦Ŝ(n)¦2) grows at least as fast as the Flory predictions for the usual SAW, i.e., at least as fast asn3/2 ford=2 andn6/5 ford=3. In particular, if the mean square displacement of the usual SAW grows liken1.18... ind=3, as expected, then the loop-erased process is in a different universality class.
Extension of replicative lifespan in WI-38 human fibroblasts by dexamethasone treatment is accompanied by suppression of p21Waf1/Cip1/Sdi1 levels

Abstract Numerous studies have shown that supplementation of the growth medium of human fibroblasts with dexamethasone at physiologic concentrations extends replicative lifespan up to 30%. While this extension of lifespan has been used to probe various aspects of the senescent phenotype, no mechanism for the increased lifespan of human fibroblasts grown in the presence of dexamethasone has ever been identified. In the present study we present evidence that the extended lifespan of human lung fibroblasts (WI-38 cells) that occurs when these cells are maintained in culture medium supplemented with dexamethasone is accompanied by a suppression of p21Waf1/Cip1/Sdi1 levels, which normally increase as these cells enter senescence, while p16INK4a levels are unaffected. These results suggest that the delay of senescence in cultures grown in the presence of dexamethasone is due to a suppression of the senescence related increase in p21Waf1/Cip1/Sdi1. These results are consistent with models of replicative senescence in which p53 and p21Waf1/Cip1/Sdi1 play a role in the establishment of the senescent arrest.
Online medical genetics resources: a US perspective

Over the past decade daily advances in gene discovery fuelled by the human genome project have propelled molecular genetic testing into mainstream medicine. Molecular genetic testing is a sensitive, cost effective means of diagnosis, testing for carrier status, and prenatal diagnosis for many inherited disorders, and it is increasingly used for predictive and predispositional testing. Those who rely on genetic testing find it a challenge keeping up to date with information, particularly when guidelines for use lag behind the availability of tests. We looked critically at online resources relevant to geneticists, providers of primary care (who have been identified by their patients as the primary source of information on genetic testing (www.ama-assn.org/ama/pub/article/2304-2937.html)), and informed patients. 1 2 #### Summary points For geneticists, web based resources describe mendelian disorders, genetic testing in specific inherited disorders, ethical issues and resources, and protocols for screening newborn infants Few resources exist for providers of primary care, who need tools to identify high risk patients and guidelines on effective interventions Websites and directories provide information for consumers on lay organisations, the management of disease, patient advocacy, and support services We relied on our experience as medical geneticist, teachers of medical students, residents and physicians in internal medicine and family practice, and medical librarians; our participation in genetics resources on the web (GROW), which promotes the development of high quality accessible internet resources on genetics3; and the genetics in primary care project, administered by the Society for Teachers of Family Medicine and cofunded by the Health Resources and Services Administration, the National Institutes of Health, and the Agency for Health Care Policy and Research (www.mchb.hrsa.gov/html/genetics.html). We selected resources that we determined to be of high quality by using the Mitretek criteria for evaluating health information on the internet (see BMJ 's website).4 #### Uses of molecular genetic testing Diagnosis (Friedreich's ataxia, …
Venlafaxine-associated tinnitus.

Venlafaxine, an antidepressant currently indicated for major depressive disorder, generalized anxiety disorder, panic disorder, and social anxiety disorder, inhibits neuronal uptake of serotonin, norepinephrine, and dopamine.[1][1] In 18- to 65-year-old patients, the most common adverse effects
Standardization and optimization of CT protocols to achieve low dose

The increase in radiation exposure due to CT scans has been of growing concern in recent years. CT scanners differ in their capabilities, and various indications require unique protocols, but there remains room for standardization and optimization. In this paper, the authors summarize approaches to reduce dose, as discussed in lectures constituting the first session of the 2013 UCSF Virtual Symposium on Radiation Safety and Computed Tomography. The experience of scanning at low dose in different body regions, for both diagnostic and interventional CT procedures, is addressed. An essential primary step is justifying the medical need for each scan. General guiding principles for reducing dose include tailoring a scan to a patient, minimizing scan length, use of tube current modulation and minimizing tube current, minimizing tube potential, iterative reconstruction, and periodic review of CT studies. Organized efforts for standardization have been spearheaded by professional societies such as the American Association of Physicists in Medicine. Finally, all team members should demonstrate an awareness of the importance of minimizing dose.
Physical interpretation of the mathematical singularities in the continuum strain fields conventionally associated with crystal lattice dislocations

The singularities known to exist in the strain fields conventionally associated with lattice dislocations are usually regarded as unphysical, and theorists have been prone to ignore them. The result has been that vague and unconvincing arguments using analogies with more secure theories have been used to “prove” essential theorems concerning the energetics of dislocation interactions. In this article all valid theorems are derived logically from the singularities themselves, which are treated as Green's sources in terms of which, by standard methods, the physical dislocations can be described as continuous distributions. A significant bonus of this approach, compared with the conventional picture, is that the coalescence (or cancellation) of two similar (or opposite) dislocations can now be described analytically in detail.
Strontium Isotopic Composition in Individual Circumstellar Silicon Carbide Grains: A Record of s -Process Nucleosynthesis

Twenty six individual circumstellar SiC grains extracted from the Murchison meteorite were analyzed for their strontium isotopic compositions by resonant ionization mass spectrometry. Large abundance deficits were found for the $p$-process isotope ${}^{84}\mathrm{Sr}$. The measured grains had ${}^{87}\mathrm{Sr}{/}^{86}\mathrm{Sr}$ ratios indistinguishable from the primordial solar value, but several grains differed in their ${}^{88}\mathrm{Sr}{/}^{86}\mathrm{Sr}$ ratios as a consequence of the branch point at ${}^{85}\mathrm{Kr}$. The Sr isotopic data are consistent with $s$-process nucleosynthesis at moderate neutron densities.
The relation between lorazepam-induced auditory amnesia and auditory evoked potentials

We conducted a placebo-controlled double-blind investigation in 15 normal volunteers to study the time course of amnesia to auditory stimulation produced by lorazepam. We also studied the relationship between auditory amnesia and auditory evoked potentials to determine if long-latency auditory evoked potentials (LLAEPs) could be utilized as electrophysiologic predictors of memory. Amnesia was produced by administration of 0.05 mg/kg lorazepam intravenously. To separate the changes in LLAEPs due to generalized sedation from those associated with amnestic properties of a drug, a third group of subjects given 1.5 mg/kg secobarbital was included. Observed frequency and duration of amnesia to auditory stimulation after lorazepam was 58% and 3 hours, respectively (mean values), with marked diminuition of antirecall effect at 120 minutes. Administration of lorazepam increased the latency and decreased the amplitude of N1 and P3 components of LLAEPs. These changes appeared to be a result of generalized sedation rather than the amnestic properties of the drug. We failed to find a definite relationship between amnesia and changes in LLAEPs. We conclude that P3 component of LLAEPs cannot be utilized as an electrophysiologic predictor of amnesia in humans.
Factors controlling CO2 exchange on timescales from hourly to decadal at Harvard Forest

[1] We analyzed 13 years (1992−2004) of CO2 flux data, biometry, and meteorology from a mixed deciduous forest in central Massachusetts. Annual net uptake of CO2 ranged from 1.0 to 4.7 Mg-C ha−1yr−1, with an average of 2.5 Mg-C ha−1yr−1. Uptake rates increased systematically, nearly doubling over the period despite forest age of 75–110 years; there were parallel increases in midsummer photosynthetic capacity at high light level (21.5−31.5 μmole m−2s−1), woody biomass (101−115 Mg-C ha−1 from 1993−2005, mostly due to growth of one species, red oak), and peak leaf area index (4.5−5.5 from 1998–2005). The long-term trends were interrupted in 1998 by sharp declines in photosynthetic capacity, net ecosystem exchange (NEE) of CO2, and other parameters, with recovery over the next 3 years. The observations were compared to empirical functions giving the mean responses to temperature and light, and to a terrestrial ecosystem model (IBIS2). Variations in gross ecosystem exchange of CO2 (GEE) and NEE on hourly to monthly timescales were represented well as prompt responses to the environment, but interannual variations and long-term trends were not. IBIS2 simulated mean annual NEE, but greatly overpredicted the amplitude of the seasonal cycle and did not predict the decadal trend. The drivers of interannual and decadal changes in NEE are long-term increases in tree biomass, successional change in forest composition, and disturbance events, processes not well represented in current models.
Sex-specific differences in hyperoxic lung injury in mice: Implications for acute and chronic lung disease in humans

Abstract Sex-specific differences in pulmonary morbidity in humans are well documented. Hyperoxia contributes to lung injury in experimental animals and humans. The mechanisms responsible for sex differences in the susceptibility towards hyperoxic lung injury remain largely unknown. In this investigation, we tested the hypothesis that mice will display sex-specific differences in hyperoxic lung injury. Eight week-old male and female mice (C57BL/6J) were exposed to 72 h of hyperoxia (FiO2 > 0.95). After exposure to hyperoxia, lung injury, levels of 8-iso-prostaglandin F2 alpha (8-iso-PGF 2α) (LC–MS/MS), apoptosis (TUNEL) and inflammatory markers (suspension bead array) were determined. Cytochrome P450 (CYP)1A expression in the lung was assessed using immunohistochemistry and western blotting. After exposure to hyperoxia, males showed greater lung injury, neutrophil infiltration and apoptosis, compared to air-breathing controls than females. Pulmonary 8-iso-PGF 2α levels were higher in males than females after hyperoxia exposure. Sexually dimorphic increases in levels of IL-6 (F > M) and VEGF (M > F) in the lungs were also observed. CYP1A1 expression in the lung was higher in female mice compared to males under hyperoxic conditions. Overall, our results support the hypothesis that male mice are more susceptible than females to hyperoxic lung injury and that differences in inflammatory and oxidative stress markers contribute to these sex-specific dimorphic effects. In conclusion, this paper describes the establishment of an animal model that shows sex differences in hyperoxic lung injury in a temporal manner and thus has important implications for lung diseases mediated by hyperoxia in humans.
AFM Force–Distance Curves for Perfluoropolyether Boundary Lubricant Films as a Function of Molecular Polarity

AFM force–distance curves on 10-A films of Zdol, Z-Tetraol, and ZTMD were investigated using a carbon-modified AFM tip. The forces were non-specific dominated by adhesive and/or capillary forces. The snap-to distances for unbaked Zdol, Z-Tetraol, and ZTMD were 1.9, 1.0, and 0.8 nm, respectively, and decreased with increasing molecular polarity. ZTMD allowed the closest approach before snap-to, by approximately 1 nm. However, annealed samples showed an identical 1.6 nm snap-to distance, indicating that an identical perfluoropolyether backbone was presented to the AFM tip at the PFPE/air interface. The pull-out forces for unbaked Zdol, Z-Tetraol, and ZTMD were in the 15–40 nN range and increased with increasing molecular polarity and loading rate. After annealing, the pull-out forces for the baked Zdol, Z-Tetraol, and ZTMD were significantly reduced to 10–20 nN, indicating that the polar end groups were less involved by bonding to the underlying surface. Force–distance curves for single-chain unbinding and entropic elasticity were computed to be near 300 and <100 pN, respectively, indicating that the force–distance curves for the experimental tip-PFPE interactions originated from multiple PFPE interactions with the tip.
A hyperbolic tangent identity and the geometry of Padé sign function iterations

The rational iterations obtained from certain Pade approximations associated with computing the matrix sign function are shown to be equivalent to iterations involving the hyperbolic tangent and its inverse. Using this equivalent formulation many results about these Pade iterations, such as global convergence, the semi-group property under composition, and explicit partial fraction decompositions can be obtained easily. In the second part of the paper it is shown that the behavior of points under the Pade iterations can be expressed, via the Cayley transform, as the combined result of a completely regular iteration and a chaotic iteration. These two iterations are decoupled, with the chaotic iteration taking the form of a multiplicative linear congruential random number generator where the multiplier is equal to the order of the Pade approximation.
Long-term pavement performance effectiveness of preventive maintenance treatments using Markov chain algorithm

In the Long-term Pavement Performance (LTPP) study, the SPS-3 experiment was designed to assess the performance of different flexible pavement maintenance treatments, relative to the performance of untreated control sections. The experiment consists of a control section and four maintenance treatments: thin overlay, slurry seal, chip seal, and crack seal. Several studies in the past have evaluated the effectiveness of the maintenance treatments; however, there is a need to re-evaluate the results as more performance data become available. This paper uses Markov chain algorithm (MCA) to evaluate the effectiveness of maintenance treatments at the network level. For each treatment, the transition matrices were determined from the observed time series performance data for ride quality, fatigue cracking, and rutting. The advantages of using MCA includes the ability to dynamically model pavement deterioration and improvement at the same time, evaluate the impact of initial pavement conditions on the short- and long-term performance, and relative comparison of pavement performance among different maintenance treatments. The results show that different maintenance treatments have varying effectiveness depending on the distress type. For example, thin overlay is more effective in the long-term for improving IRI and rutting while chip seal seems to be a better choice in case of alligator cracking. Generally, different seals considered in the SPS-3 experiment are more effective when applied to a network in good condition while overlay is more effective for a network in poor condition.
Langsian psychology and physics

This paper relates the primitives of Robert J. Langs' psychology to those of physics. The off-boundary properties of all known natural processes are decided by their boundary behavior. Langs' formulations add the process of psychotherapy and general interpersonal exchange, that is two or more party dialogues, to this. His theory distinguishes the boundary, as does physics, into a frame and two-sided action site, referred to as a gate here. His ideas develop by moving from data on the boundary as a gate to the nature of the frame. His line of approach contrasts with Freud's direction toward the process interior and to Jung's across it. Placing his boundary ideas into where he enters psychology repeats a line of thought in the history of physics on the relation of a system to its environment. This paper notes that much of Freud's theory is grounded in the first law of thermodynamics and Jung's the second. Langs' theory subsumes both laws with a holistic boundary model.
Inconclusive evidence to recommend prophylactic antibiotics to prevent complications following dental implant treatment

Original Article Esposito M, Coulthard P, Oliver R, Thomsen P, Worthington HV. Antibiotics to prevent complications following dental implant treatment (Cochrane Review). In: The Cochrane Library, Issue 3, 2003. Oxford: Update Software. Date of most recent amendment: 17 April 2003 Level of Evidence 3a Purpose This review tested the null hypothesis of no difference in the proportion of prosthetic failures, implant failures, postoperative infections, and adverse events of patients receiving a placebo or no antibiotic treatment. Source of Funding Swedish Medical Research Council (9495) SWEDEN Sahlgrenska Academy at Goteborg University SWEDEN The University Dental Hospital of Manchester UK Type of Study/Design Systematic review
Diurnal fluctuations of inorganic orthophosphate in pineapple (Ananas comosus L., Merr.) leaves and a possible role of ATPase

Abstract An increase in size of inorganic orthophosphate (Pi) pools was observed in the leaves of the Crassulacean acid metabolism (CAM) plant, pineapple (Ananas comosus L., Merr.). This occured as titratable acid levels approach their maxima. The Pi pool size did not decrease until titratable acid levels were close to their minima. ATPase levels in the leaves of pineapple and other CAM plants correlate well with the amplitude of the diurnal fluctuations in net titratable acidity. Levels of ATPase estimated from in vitro assays were sufficient to support a hypothesis that ATPase acts as a pump for transport of organic acids accumulated in the vacuole at night into the cytoplasm. However, considerations of pH optima and energy of activation discontinuities do not support the hypothesis that this enzyme is directly responsible for the Pi fluctuations observed. It seems more probable to explain the correlation of ATPase levels and diurnal fluctuations in net titratable acidity in terms of the hypothesis of von Willet. In this hypothesis he suggests that Pi functions to stimulate the conversion of malate to phosphoenol pyruvate and carbon dioxide.
Fouling and rejection behavior of ceramic and polymer-modified ceramic membranes for ultrafiltration of oil-in-water emulsions and microemulsions

Abstract The effectiveness of poly(vinylpyrrolidone) (PVP)-modification of a zirconia-based ultrafiltration membrane was investigated for the treatment of oil-in-water (o/w) emulsions. Fouling, hydraulic permeability, flux decline, and solute rejection for modified and native membranes were evaluated using a diagnostic o/w emulsion as well as an emulsion prepared using a commercial cutting oil. The native membrane was irreversibly fouled by both the o/w microemulsion and the commercial cutting oil emulsion. In contrast, irreversible fouling was not observed for the PVP-modified membrane. The main fouling agent for the diagnostic o/w microemulsion was identified as the anionic surfactant octanoate, which lead to an irreversible decline of initial membrane hydraulic permeability of up to 20%. Adsorption of surfactant species onto the native membrane surface were attributed to charge screening due to high ionic strength environment and presence of hydroxyl groups on the zirconia surface. Analysis of permeate flux decline and membrane resistance behavior suggests that membrane fouling was mainly due to a solute cake (gel) layer buildup at the membrane surface. However, the possibility of some internal pore plugging, due to deposition of small surfactant molecules, micelles or oil droplets, during the initial few minutes of filtration runs, could not be ruled out. Improved oil rejection (two-fold for the microemulsion and over 20% for the cutting oil emulsion) with the modified membrane compared to the native membrane was attributed to repair (or narrowing) of defects (or ‘pin-holes’) of the native membrane upon polymer grafting.
IV. The Origins of the Birmingham Caucus

In 1868 the Birmingham Liberal Association won the first of a series of dazzling victories in parliamentary and municipal elections. Contemporaries immediately recognized the presence of a new phenomenon in English politics: disciplined control of a mass electorate by a tightly organized party apparatus. At first glance the Liberal machine seemed un-English, and the Tories gleefully imported an American epithet to describe it. The traditional interpretation of the caucus, as set forth by Ostrogorski, followed contemporary opinion in emphasizing the novelty of the institution. In his view, ‘the organization of the electoral masses’ by the Liberal Association represented a sharp break with the past. He traced its origin to the minority clause of the Reform Act of 1867, which gave each Birmingham elector two votes to divide among the candidates for three seats, thus challenging the Liberals to develop an organization capable of circumventing the Act. After their success in the ‘vote as you are told’ election of 1868, the Liberal politicians, according to Ostrogorski, continued to use the caucus as a contrivance for manipulating an electorate that otherwise might have exercised independent judgment. This interpretation remains of considerable value, particularly in its treatment of the oligarchic implications of modern democracy. Nevertheless, Ostrogorski’s analysis tends to be misleading and one-sided. The Liberal politicians, like the priests in Voltaire’s account of the history of religion, are depicted as consciously constructing an institution ex nihilo to meet their own needs and purposes. Ostrogorski attributes too much to calculation and too little to the historical process that created the materials out of which the caucus was built and the foundations on which it rested.
Bradycardia with carotid system infusions of cold blood during endarterectomy.

A method of local cerebral hypothermia has been used over the past nine years to mitigate the effects of cerebral ischaemia during carotid endarterectomy. Bradycardia, seen immediately after initiation of a 500 cc infusion of cold blood in the carotid artery, has been quite transient in duration. Atrio-ventricular conduction is prolonged, and periods of 15 seconds of asystole have been recorded. It would appear that the bradycardia is related to a sudden cerebral cold stimulus to the hypothalamus.
Effects of Student Displacement in Louisiana During the First Academic Year After the Hurricanes of 2005

The combined impact of Hurricanes Katrina and Rita in 2005 left the education system in the Gulf Coast region of the United States with tremendous challenges to rebuild infrastructure, reestablish services, and accommodate the movements of students that occurred as result of the storms. This article focuses on Louisiana's public school students, of whom 1/4 were displaced as a result of the storms. It explores the experiences of students and the effects of student movements on student achievement and on the state's public education system during the first academic year following the hurricanes. Results suggest that, overall, the education system handled the disruptions of the disaster relatively well. However, more detailed examinations show that some displaced students had problems such as nonenrollment or poor attendance, mental health or behavioral problems, and academic setbacks. Negative achievement effects, which were small overall, were most pronounced among students who remained displaced for the ...
The Russian and Ukrainian Information Technology Outsourcing Market: Potential, Barriers and Management Considerations

This study describes the advantages and disadvantages of information technology outsourcing to Ukraine and Russia. The results assist technology managers who wish to make an informed decision on whether or not to outsource information technology projects to Russia/Ukraine, considering two important issues: (1) the political, economic, and social landscape, and the advantages and disadvantages of choosing to locate information technology projects in the region and (2) the Russian/Ukrainian information technology workers’ teamwork perceptions. By understanding the countries and the potential information technology workers within that country, organizations should be able to develop management policies to improve chances of success. While the results indicate that well-educated and teamwork-oriented Russian and Ukrainian information technology employees may increase the chances of information technology outsourcing success, the authors remain skeptical regarding the political, economic, legal, social, and bu...
A High-Resolution VLA and Optical Study of NGC 604

The radio structure of the supergiant H II region NGC 604 in the dwarf spiral galaxy M33 has been observed at 3.6 cm with a resolution of ~2'' (~8 pc) down to an rms noise level of ~15 μJy. At least six radio components can be distinguished embedded in a more extended halo. Each radio component requires ionizing photon fluxes in the range 6-44 times that of Orion A, and the entire nebula requires about 350 times that of Orion A. The rms electron densities are in the range of a few to ~100 cm-3, and the total ionized gas mass is ~3×106 M☉. Even though the photon fluxes required to maintain ionization are large, the radiation density in each radio component is substantially less than that in Orion A due to the much larger size of the radio components in NGC 604. From a comparison of radio and Hα images provided by D. Hunter, we have derived the optical depth at Hα over the face of the nebula. Visual extinctions are greatest toward the bright radio components (2.8 to 1.7 mag) and 0.5 mag over the rest of the nebula. The increased extinction toward the bright radio components implies that the dust is physically associated with these components and requires that the dust is present in the ionized gas. The dust is probably mostly leftover from the natal clouds from which the clusters formed, although some enhancement may have occurred via photoionization of accretion disks associated with the cluster stars and/or molecular cloudlets that have been overrun by the ionization front of the nebula.
Sustained ventricular tachyarrhythmias within 2 months of acute myocardial infarction: Results of medical and surgical therapy in patients resuscitated from the initial episode

Sustained ventricular tachycardia or fibrillation that develops during the early recovery period after acute myocardial infarction is a common clinical problem whose management remains controversial. Fifty-three patients who survived an initial episode of sustained ventricular tachycardia or fibrillation occurring between 3 and 60 days (mean ± SD 21 ± 16) after myocardial infarction were evaluated. Most of these patients had had a large (peak creatine kinase = 1,729 ± $82 IU) complicated infarction. Forty-two (79%) of the 53 patients had had repetitive sustained ventricular arrhythmias and the condition of 19 of these could not be stabilized with drug therapy. Twenty-eight patients received medical therapy only. Twenty-four survived and were discharged from the hospital. Twenty-five patients underwent infarctectomy or aneurysmectomy either on an emergency basis (16 patients) or electively because of coexistent heart failure orangina (9 patients). Intraoperative mapping was attempted in these patients but was completely successful in only 13 (52%). Operative mortality was 16% with all deaths occurring in patients who were in shock before surgery. Five of 21 surgically treated survivors required long-term antiarrhythmic therapy. Twenty-one of 24 patients medically treated remain alive and well after 15 ± 10 months of follow-up. Nineteen of 21 surgically treated patients remain alive and well after 17.9 ± 11 months. One of these patients required reoperation for severe mitral regurgitation. These results confirm the poor medical prognosis of sustained ventricular tachyarrhythmias that present during the first 2 months after myocardial infarction but demonstrate that an acceptable rate of survival can be achieved with a combined medical and surgical approach to therapy.
Galvanomagnetic Studies of Bismuth Films in the Quantum-Size-Effect Region

Bismuth films (200-1400 \AA{}) were grown epitaxially on freshly cleaved mica substrates. These films consisted of a mosaic of equally oriented crystallites averaging several microns in diameter. The plane of the films coincided with the trigonal plane of Bi. We have studied the thickness dependence of the resistivity, the Hall coefficient, and the transverse magneto-resistance, by gradually varying the thickness of a single film which was kept under high vacuum during the entire experiment. The resistivity at 360 and 77 \ifmmode^\circ\else\textdegree\fi{}K is a smooth monotonic function of the thickness. At 12 \ifmmode^\circ\else\textdegree\fi{}K, we observed small oscillations in the resistivity and in the magnetoresistance. These oscillations are regarded as probable manifestations of the quantum size effect (QSE). The thickness dependence of the Hall coefficient is in striking disagreement with the predictions of the infinite-potential-well model. Better agreement between the theory and experimental results is obtained when we assume a less rigid boundary condition. Also for several films we have investigated the temperature dependence of these three transport coefficients and found it to be quite different from that of bulk bismuth. We have attempted to explain these results in terms of the behavior of the carrier concentration and of the different scattering mechanisms that can come into play in these films.
Temporally Distinct and Ligand-Specific Recruitment of Nuclear Receptor-Interacting Peptides and Cofactors to Subnuclear Domains Containing the Estrogen Receptor

Ligand binding to estrogen receptor (ER) is presumed to regulate the type and timing of ER interactions with different cofactors. Using fluorescence microscopy in living cells, we characterized the recruitment of five different green fluorescent protein (GFP)-labeled ER-interacting peptides to the distinct subnuclear compartment occupied by blue fluorescent protein (BFP)-labeled ERα. Different ligands promoted the recruitment of different peptides. One peptide was recruited in response to estradiol (E2), tamoxifen, raloxifene, or ICI 182,780 incubation whereas other peptides were recruited specifically by E2 or tamoxifen. Peptides containing different sequences surrounding the ER-interacting motif LXXLL were recruited with different time courses after E2 addition. Complex temporal kinetics also were observed for recruitment of the full-length, ER cofactor glucocorticoid receptor-interacting protein 1 (GRIP1); rapid, E2-dependent recruitment of GRIP1 was blocked by mutation of the GRIP1 LXXLL motifs to LXX...
Analysis of standard multiport versus single-site access for laparoscopic skills training

Single-site-access (SSA) laparoscopy is more challenging to perform than multiport (MP) laparoscopy. This study examined the effect of MP versus SSA skills training on laparoscopic performance using surgically naive medical students. For the study, 40 medical students at the end of their first year were randomized into two groups. Both groups were trained in four basic laparoscopic drills (peg, rope, bean drop, pattern cutting) using a standard MP setup (group 1) and an SSA approach (group 2). The time and number of repetitions required to attain proficiency were recorded. Each group then crossed over to the alternate approach and repeated the sequence. Data are presented as mean ± standard deviation, and statistical analysis was performed using the two-tailed, unpaired t test. The total times required to attain proficiency for the SSA and MP approaches were not significantly different between the MP-trained group (234.0 ± 114.9 min) and the SSA-trained group (216.4 ± 106.5 min) (p = 0.67). The MP-trained group required less time to reach proficiency on the standard MP setup than the group using the SSA approach (119.1 ± 69.7 vs. 178.0 ± 93.4 min; p = 0.058) and significantly fewer repetitions (77.6 ± 42.6 vs. 118.8 ± 54.3; p = 0.027). The SSA-trained group required significantly less time to reach proficiency on the MP setup than the standard MP-trained group (38.4 ± 29.4 vs. 119.1 ± 69.7 min; p = 0.0013) and needed only a mean of 26.9 repetitions. When the standard MP trainees crossed over to the SSA setup, they required significantly less time to reach proficiency with the SSA approach than the SSA-trained group (114.8 ± 50.5 vs. 178.0 ± 93.4 min; p = 0.026) but required more repetitions than with the MP approach (86.2 ± 35.2 vs. 77.6 ± 42.6; nonsignificant difference). Laparoscopic SSA skills training results in longer times and more repetitions to achieve proficiency than MP training, but the skills acquired transfer well to the MP approach.
Ethical principles in anthropological research: one or many?

Among the many problematic areas that have characterized the growing concern with ethics in the profession of anthropology has been the problem of maintaining different relationships with various people with whom the anthropologist has to deal and about whom he or she should have some concern. A recent exploration of this problem is a series of articles (Social Problems 1980) that bring together applied anthropologists and sociologists in a further effort to explore some of the vexing dilemmas that confront the field-worker. Of particular interest in this corpus is the paper by William May (1980), a philosopher who was invited to participate in the project and final conference on fieldwork that led to the volume just mentioned. In this volume, as is the case in most earlier work on field research ethics, there is the pervasive implication that the anthropologist has one overriding obligation that should be recognized, some particular ethic that should be observed to the exclusion of others. In the papers, advocacy of the powerless is favored by some, evenhanded treatment of all by others, a favoring of those being studied by yet others. May, as will be detailed shortly, thinks that anthropologists are "moving in the direction of a covenantal ethic" (1980:368) in their field research. In this paper I argue that we cannot expect to find a single ethic that will be adequate to all field situations because the ethical theories or principles that could be applied to all relationships are unlikely to be acceptable to all anthropologists, whereas those that might be more acceptable are not applicable t o all relationships. I will first identify the relationships that characterize the world within which the anthropologist works, using the principles that have been adopted by the American Anthropological Association (AAA) as a basis for the discussion. I will then argue that the major ethical principle or "moral theories" as set forth by May d o not permit us to find a single ethic that will be both acceptable and workable in all relations. Finally, it may be hoped that this discussion will help move the issue of understanding ethics in fieldwork from the level of reiterative case histories and doctrinal dogma to a discussion of the theory underlying ethics in society.
The Perinatal Period, a Window of Opportunity for Enhancing Parent-Infant Communication: An Approach to Prevention.

The perinatal period, broadly defined, encompasses the time frame from one year before to 18 to 24 months after the birth of the child. This period constitutes a window of opportunity through which parent-infant interaction may be reinforced, offering the possibility of decreasing the risk of family dysfunction. This review article clarifies the relationship between the enhancement of parent-infant interactions and the prevention of child abuse and neglect. It contains a detailed discussion of the capabilities of the newborn and places in perspective the difficulty experienced when parents who were themselves mistreated in childhood struggle to establish a system of communication with their own newborn children. The perinatal intervention program, a program intended to teach new parents the skills of interaction with their newborns, is described and placed into perspective with other perinatal programs which have been reported to be capable of augmenting the capacity for communication. The authors review the research data demonstrating the efficacy of these perinatal parent-infant programs. The paper concludes with a review of effective interventions, a discussion of what can be expected of each, and suggestions for the practical application of the programs during the perinatal period. The authors recognize that no program taken in isolation is sufficient; taken together they have the ability to improve parent-child relations, and they thus constitute a multifaceted approach to the prevention of child abuse and neglect.
Enhanced Diastereoselectivity in β-Mannopyranosylation through the Use of Sterically Minimal Propargyl Ether Protecting Groups

2-O-Propargyl ethers are shown to be advantageous in the 4,6-O-benzylidene acetal directed β-mannosylation reaction. The effect is most pronounced when the O3 protecting group is a bulky silyl ether or a glycosidic bond; however, even with a 3-O-benzyl ether, the use of a 2-O-propargyl ether results in a significant increase in diastereoselectivity. The beneficial effect of the propargyl ether is thought to be a combination of its minimal steric bulk, as determined by a measurement of the steric A-value and of its moderately disarming nature, as reflected in the pKa of propargyl alcohol. Conversely, the application of a 3-O-propargyl ether in the benzylidene acetal directed mannosylation has a detrimental effect on stereoselectivity, for which no explanation is at present available. Deprotection is achieved by base-catalyzed isomerization of the propargyl ether group to the corresponding allenyl ether, followed by oxidative cleavage with N-methylmorpholine N-oxide and catalytic osmium tetroxide.
Product Partition Models for Normal Means

Abstract I consider probability models for the estimation of normal means that allow for some of the means to be equal. These probability models, called product partition models, specify prior probabilities for a random partition. The posterior probability of the partition given the observations has the same form. The resulting estimate of the means—the product estimate—is obtained by conditioning on the partition and summing over all possible partitions. The large number of computations involved leads to the use of Markov sampling to compute the product estimate. I compare the product estimate to other estimates of normal means both in a simulation study and in the prediction of baseball batting averages.
env1 Mutant of VPS35 gene exhibits unique protein localization and processing phenotype at Golgi and lysosomal vacuole in Saccharomyces cerevisiae

The yeast vacuole is functionally and structurally equivalent to the mammalian lysosome. Delivery of resident and cargo proteins to the lysosome is vital for proper cellular operations, and failure to correctly target proteins to the organelle is correlated with the development of neurodegenerative and lysosomal storage diseases. We previously reported a novel mutant screen for vacuolar trafficking defects in yeast Saccharomyces cerevisiae that resulted in the isolation of env1, an allelic mutant of VPS35. As a member of the retromer complex, Vps35p binds directly to cargos and facilitates their retrograde transport to trans Golgi from endosomes. Our previous studies established that env1 exhibits unique pleiotropic phenotype in comparison to other tested VPS35 alleles including severe growth sensitivity to hygromycin B and internal accumulation of the precursor form of the vacuolar enzyme carboxypeptidase Y. Here, through a combination of sub-cellular fractionation and indirect immunofluorescence microscopy, we confirm and extend the unique phenotype of env1 to processing and localization of additional proteins within the vacuolar trafficking pathway. In comparative studies with a null and an allelic mutant of VPS35, env1 exhibited unique processing defects of retromer-independent vacuolar membrane enzyme alkaline phosphatase at the vacuole and significant Golgi localization of retromer cargos Vps10p and Kex2p despite compromised trafficking at the Golgi and late endosome interface.
Snail shells in a practical application of statistical procedures

This paper is based upon a laboratory exercise designed for biology students in secondary schools or those taking introductory biology laboratory courses in colleges and universities. This exercise requires a set of calipers, a calculator and populations of snail shells collected either from the wild or obtained from a biological supply house. The exercise illustrates an inexpensive means by which students can conduct their own measurements and analysis of biological specimens. Snail shells can be measured for their height, width, aperture dimension, and weight. This provides data which can be used to illustrate and apply the concepts of probability, normal distribution, standard deviation, homogeneity of variance, and Student's t-test in a biological context. The students do not use computers in this exercise so that, through the manual completion of worksheets with paper and pencil, they can more effectively learn the application of statistical methodology.
Incubator rearing of infant rats without the mother: Effects on adult emotionality and learning

Eight newborn rats, from 3 litters, were separated from the mother and reared during the usual 3-week nursing period in an artificial environment which included an incubator, a warm, moist, pulsating surrogate mother, and special feeding procedures. The incubator animals showed some superiority over mother-reared littermates in performance on the Hebb-Williams test; and, on measures taken in the open field, the incubator animals showed a greater change over trials. Contrary to previous experimental results, our findings indicate that, at least in the rat, maternal deprivation may affect behavioral patterns but does not necessarily and inevitably result in a deficit in adult behavior.
An analysis of the series of moderately heavy fermion materials: CeSn3, USn3, and NpSn3

Abstract The materials CeSn 3 , USn 3 , and NpSn 3 are all moderately heavy Fermion compounds with electronic specific heat coefficients of 73, 169, and 242 mJ/mole K 2 . CeSn 3 is known as a mixed valent system and NpSn 3 is a weak itinerant antiferromagnet. All three are strongly enhanced. Being in the relatively simple Au 3 Cu structure, they form an excellent set of materials to study as representatives of strongly enhanced systems. One would like to ascertain what properties can be determined from band calculations based on density functional theory in the local density approximation. It has already been shown that the Fermi surface topology of CeSn 3 can be well described in this way even though the experimental masses are much larger than the band results. The enhancement factor for USn 3 is even larger and NpSn 3 is indeed predicted to go magnetic. We present here fully relativistic SCF calculations for these materials and discuss the relation between our results and what is known experimentally.
Quantification of free 17β-estradiol in pregnancy plasma by gas-liquid chromatography using electron-capture detection

Abstract A sensitive GLC method for the measurement of free plasma 17β-estradiol using electron-capture detection is described. The technique involves extraction of the hormone from plasma, a series of solvent partitions and pH adjustments, thin-layer chromatography, and esterification of the hormone with heptafluorobutyric anhydride. Quantification of the latter derivative with an electron-capture detector has allowed measurement of as little as 4.6 ng of free 17β-estradiol per 10 ml of plasma. In 61 plasma samples obtained from week 9 to 40 of pregnancy, levels of unconjugated plasma 17β-estradiol ranged from 46 ng to 3.31 μg 100 ml .