cssi/SciSciGPT-SciSciNet huggingface dataset:
Design and optimization of GaN lateral polarization-doped super-junction (LPSJ): An analytical study

A 2D analytical model for breakdown voltage (BV) and specific on-resistance (R on, sp ) of GaN lateral polarization-doped super-junction (LPSJ) devices has been developed. The electric field along the critical path has been modeled and compared with 2D simulation results, followed by breakdown voltage calculation using impact ionization integral. Design space and optimization of LPSJ has been disused in terms of n/p pillar doping, thickness and aluminum composition x Al in grading AlGaN. The 2D analytical model represents a more realistic performance limit than the 1D model and the R on, sp of LPSJ with x Al = 0.3 shows > 10x reduction over conventional GaN junctions for BV>2 kV. It can provide useful guidelines for the development of LPSJ and the design criteria to achieve minimum Ron, sp.
Testing and Evaluation of Polyurethane-Based GFRP Sandwich Bridge Deck Panels with Polyurethane Foam Core

AbstractThis paper presents the evaluation of an innovative low-cost small-scale prototype deck panel under monotonic and fatigue bending. This new system introduces a trapezoidal-shaped polyurethane foam core with a thermoset polyurethane resin that has a longer pot life to facilitate the infusion process. The proposed panel exhibited a higher structural performance in terms of flexural stiffness, strength, and shear stiffness. The panels consist of two glass fiber–reinforced polymer (GFRP) facings with webs of bidirectional E-glass–woven fabric that are separated by a trapezoidal-shaped low-density polyurethane foam. The GFRP panels were manufactured using a one-step vacuum-assisted resin transfer molding process. The specimens studied were constructed in the Composite Manufacturing Laboratory in the Mechanical and Aerospace Engineering Department at Missouri University of Science and Technology. Small-scale prototype deck panels were tested both statically and dynamically in four-point bending to inves...
Extravasation cyst of the maxilla. Report of a case.

Abstract 1. 1. A review of the literature has produced only one possible case of extravasation cyst occurring in the maxilla. 3 2. 2. We have presented a case in which a radiolucent lesion occurred in the maxilla in the presence of vital teeth. On exploration, the cavity was found to be devoid of contents. 3. 3. Postoperative examination revealed a normal healing pattern at 4 months and 4 years. 4. 4. As this case meets the criteria described by Olech, Sicher, and Weinmann, 4 there is no doubt that the extravasation cyst may occur in the maxilla as well as in the mandible.
Future Mm/Submm Instrumentation and Science Opportunities: Example of Deuterated Molecules

During the next decade a tremendous advance will take place in instrumentation for spectroscopy of the interstellar medium. Major new facilities (ALMA, SOFIA, APEX, LMT, Herschel and others) will be constructed and commissioned, so that the science opportunities, in the field of astrochemistry, will increase by a huge factor. This will be enhanced by the new receivers with greater bandwidth and sensitivity. The new opportunities will be in the area of astrochemistry of distant objects, through greater sensitivity, or new spectral ranges due to the platforms above the Earth's atmosphere. Various aspects of new spectral ranges are discussed, with emphasis on H2O lines, features previously hidden under H2O or O2 lines, light hydrides and particularly on deuterium in molecules. Recently, multiply deuterated species have been detected, e.g. ND3, in cold dense regions of the interstellar medium. It is argued here that it is possible that so much deuterium could be trapped, by the fractionation process, into heavy molecules such as ND3, etc..., and species such as H2D+ and possibly D2H+, that D and HD might be depleted. This would be the mechanism for the large dispersion of [D]/[H] values found in the interstellar medium. Light molecules (hydrides and deuterides) generally have large fundamental rotation frequencies, often lying in the HIFI bands. The deuterides are a specially suitable case, because the species exist mainly in cold dense regions, where the molecules are in the ground states and THz observations will best be carried out by absorption spectroscopy against background dust continuum sources such as Sgr B2 and W49N.
Spin-1/2 equation with indefinite metric

We study a Schrodinger equation involving a Hamiltonian that is a second-order differential operator, describes free spin-1/2 particles with both energy signs and a definite mass, and depends on a parameterG. One obtains the usual Dirac Hamiltonian by settingG=±i, but for real values ofG the one-particle theory developed here possesses an indefinite metric, so negative energy states have negative normalization. Although the new equation is not manifestly covariant, it is demonstrated that it can be made invariant under proper orthochronous Poincare transformations; it is also invariant under the CPT transformation and charge conjugation, but not, as we interpret it, under space inversion.
Localization of the binding site for modified Gb3 on verotoxin 1 using fluorescence analysis.

Verotoxins (VTs) from Escherichia coli elicit human vascular disease as a consequence of specific binding to globotriaosylceramide (Gb3) receptors on endothelial cell surfaces. Molecular models based on the VT1 crystal structure were used previously to investigate the structural basis for receptor recognition by VT1 and other verotoxins. Interestingly, these model-based predictions of glycolipid binding to VT1 differ somewhat from recently published structural data from cocrystals of the VT1 B-subunit (VT1B) and an analogue of the sugar moiety of Gb3. In this study, fluorescence spectroscopy was used to test model-based predictions of the location of Gb3 binding on the B-subunit pentamer of VT1. Resonance energy transfer was used to calculate the distance from a coumarin probe used to replace the acyl tail of Gb3 and the single tryptophan residue (Trp34) present within each VT1B monomer. The observed energy transfer efficiency (greater than 95%) suggests that these two moieties are approximately 13.3 A ap...
More than a Walk in the Park: The Indiana Global Health Research Meeting

The Indiana Global Health Research Working Conference of October 2012 was convened by a planning committee representing Indiana’s research-intensive universities (Indiana University, Purdue University, and the University of Notre Dame). The event was organized as an open-space meeting with six thematic emphases and pre-conference keynote papers. Within their domains of common interest, attendees developed forme fruste research project abstracts that represent a future-oriented agenda for global health research. The organizational principles and purposes of this meeting are explicated with a concluding commentary on the agenda for research.
Bone: Formation by Autoinduction

Wandering histiocytes, foreign body giant cells, and inflammatory connective-tissue cells are stimulated by degradation products of dead matrix to grow in and repopulate the area of an implant of decalcified bone. Histiocytes are more numerous than any other cell form and may transfer collagenolytic activity to the substrate to cause dissolution of the matrix. The process is followed immediately by new-bone formation by autoinduction in which both the inductor cells and the induced cells are derived from ingrowing cells of the host bed. The inductor cell is a descendant of a wandering histiocyte; the induced cell is a fixed histiocyte or perivascular young connective-tissue cell. Differentiation of the osteoprogenitor cell is elicited by local alterations in cell metabolic cycles that are as yet uncharacterized.
An alternative Indian model

Abstract This paper utilizes the dualistic model of development to analyze the development of three regions: Northeast Asia, China, and India. There are many similarities between the development processes experienced by the first two regions. They involved rapid agricultural growth as a foundation for the growth of labor-intensive manufacturing. However, India's growth process seems to have skipped over the stage of labor-intensive manufacturing growth. Switching to a more labor-intensive growth process is often seen to be dependent on reform of India's labor laws. This paper argues that such reform will not work. The labor intensity of the growth process is dependent on rapid growth in agriculture. Without this, structural change will slow and inequality worsen. The latter will likely result in a deterioration of state effectiveness.
Spatial Inequity and National Territory: Remapping 1905 in Bengal and Assam*

In 1905, Viceroy Nathaniel Curzon applied well-worn principles of imperial order to reorganize northeastern regions of British India, bringing the entire Meghna-Brahmaputra river basin into one new administrative territory: the province of Eastern Bengal and Assam. He thereby launched modern territorial politics in South Asia by provoking an expansive and ultimately victorious nationalist agitation to unify Bengal and protect India's territorial integrity. This movement and its economic programme (swadeshi) expressed Indian nationalist opposition to imperial inequity. It established a permanent spatial frame for Indian national thought. It also expressed and naturalized spatial inequity inside India, which was increasing at the time under economic globalization. Spatial inequities in the political economy of uneven development have animated territorial politics in South Asia ever since. A century later, another acceleration of globalization is again increasing spatial inequity, again destabilizing territorial order, as nationalists naturalize spatial inequity in national territory and conflicts erupt from the experience of living in disadvantaged places. Remapping 1905 in the long twentieth century which connects these two periods of globalization, spanning eras of empire and nation, reveals spatial dynamics of modernity concealed by national maps and brings to light a transnational history of spatial inequity shared by Bangladesh and Northeast India.
Effects of matrix microstructure and particle distribution on fracture of an aluminum metal matrix composite

Abstract This paper presents the results of a study on the effects of matrix microstructure and particle distribution on the fracture of an aluminum alloy metal matrix composite containing 20% by volume SiC particulate. The matrix microstructure was systematically varied by heat treating to either an under- or over-aged condition of equivalent strength, and was characterized using a combination of techniques. Quantitative metallographic techniques were utilized to characterize the material with respect to size, size distribution, and particle clustering, while transmission electron microscopy was utilized to characterize the details of the matrix microstructure in addition to the effects of aging on the character of the particle/matrix interfaces. Fracture experiments were conducted on smooth tensile, notched bend, shortrod toughness, and on specimens designed to permit controlled crack propagation, in an attempt to determine the effects of matrix microstructure and clustered regions on the details of damage accumulation. Large effects of microstructure on the notched properties were obtained with little effect of microstructure on tensile ductility. It is shown that the micromechanisms of fracture are significantly affected by the details of the matrix microstructure, interface character, and degree of clustering in the material. Fracture of the SiC was predominant in the underaged materials, with a preference for failure in the matrix and near the interface in the overaged material. Metallographic and fractographic analyses revealed that clustered regions were preferred sites for damage initiation in both the aging conditions tested, while preliminary results additionally indicate that damage accumulation ahead of a propagating crack also tended to occur in clustered regions.
Magnetic resonance imaging in pediatric status epilepticus: not a routine, but a more focused indication.

Magnetic resonance imaging in pediatric status epilepticus: not a routine, but a more focused indication ANDREA PORETTI | ADAM L HARTMAN | THIERRY AGM HUISMAN 1 Division of Pediatric Radiology, Russell H Morgan Department of Radiology and Radiological Science, The Johns Hopkins School of Medicine, Baltimore. 2 Departments of Neurology and Pediatrics, The Johns Hopkins School of Medicine, Baltimore, MD, USA.
Association between sitting and occupational LBP

Low back pain (LBP) has been identified as one of the most costly disorders among the worldwide working population. Sitting has been associated with risk of developing LBP. The purpose of this literature review is to assemble and describe evidence of research on the association between sitting and the presence of LBP. The systematic literature review was restricted to those occupations that require sitting for more than half of working time and where workers have physical co-exposure factors such as whole body vibration (WBV) and/or awkward postures. Twenty-five studies were carefully selected and critically reviewed, and a model was developed to describe the relationships between these factors. Sitting alone was not associated with the risk of developing LBP. However, when the co-exposure factors of WBV and awkward postures were added to the analysis, the risk of LBP increased fourfold. The occupational group that showed the strongest association with LBP was Helicopter Pilots (OR=9.0, 90% CI 4.9–16.4). For all studied occupations, the odds ratio (OR) increased when WBV and/or awkward postures were analyzed as co-exposure factors. WBV while sitting was also independently associated with non-specific LBP and sciatica. Vibration dose, as well as vibration magnitude and duration of exposure, were associated with LBP in all occupations. Exposure duration was associated with LBP to a greater extent than vibration magnitude. However, for the presence of sciatica, this difference was not found. Awkward posture was also independently associated with the presence of LBP and/or sciatica. The risk effect of prolonged sitting increased significantly when the factors of WBV and awkward postures were combined. Sitting by itself does not increase the risk of LBP. However, sitting for more than half a workday, in combination with WBV and/or awkward postures, does increase the likelihood of having LBP and/or sciatica, and it is the combination of those risk factors, which leads to the greatest increase in LBP.
Complications Following Surgical Intervention for Stress Urinary Incontinence: A National Perspective

Aims: Stress urinary incontinence (SUI) impacts many women. Treatment is primarily surgical. Post-operative morbidity considerably aiects individuals and the health care system. Our objective is to describe complications following surgery for SUI and how they aiect resource utilization. Methods: Utilizing the Nationwide Inpatient Sample (a nationally representative dataset), 147,473 patients who underwent surgery for SUI from 1988 to 2000 were identi¢ed by ICD-9 codes. Comorbid conditions/complications were extracted using ICD-9 codes, including complication rates, length of stay (LOS), hospital charges, and discharge status. Results: Overall complication rate was 13.0% (not equal to sum of complication sub-types, as each woman may have had ¼ 1 complication), with 2.8% bleeding, 1.4% surgical injury, 4.3% urinary/renal, 4.4% infectious, 0.1% wound, 1.1% pulmonary insu⁄ciency, 0.5% myocardial infarction, 0.2% thromboembolic. The ‘‘gold standard’’ surgical technique for SUI, the pubovaginal sling, had the lowest morbidity at 12.5%. Mean LOS increased with morbidity: from 2.9 to 4.1 to 6.1 days for those with 0, 1, and ¼2 complications respectively (P < 0.001). Similarly, in£ation-adjusted hospital charges increased with morbidity: from $7,918 to $9,828 to $15,181 for those with 0, 1, and ¼2 complications respectively (P < 0.001). The percentage of patients requiring post-discharge subacute or home care increased with morbidity: from 4.4% to 8.4% to 14.3% for those with 0, 1, and ¼2 complications (P < 0.001). Conclusions: A substantial percentage of women experience complications following surgery for SUI. Post-operative morbidity leads to dramatically increased resource utilization. Prospective studies are needed to identify pre-operative risk factors and intraoperative process measures to optimize the quality of care. Neurourol. Urodynam. 24:659 ^665, 2005. 2005 Wiley-Liss, Inc.
Reporting of estimated glomerular filtration rate: effect on physician recognition of chronic kidney disease and prescribing practices for elderly hospitalized patients.

BACKGROUND Physician recognition of chronic kidney disease (CKD) in elderly patients has been noted to be poor. These patients are at increased risk of medication dosing errors and acute renal failure. OBJECTIVE To investigate the effect of reporting estimated glomerular filtration rate (GFR) of elderly hospitalized patients on physician recognition of CKD and physician prescribing behaviors. DESIGN A retrospective combined with a prospective medical record review project. SETTING A large academic medical center. PATIENTS Patients included were 65 years of age or older and had creatinine values within the normal laboratory range (< 1.6 mg/dL). INTERVENTION Reporting a calculated estimate of GFR to physicians. MEASUREMENTS Rates of recognition of CKD were examined before and after the intervention. The effects of the intervention on prescription of renal-dosed antibiotics and nonsteroidal anti-inflammatory drugs (NSAIDS) and cyclooxygenase- 2 inhibitors (COX-2) at hospital discharge were assessed. RESULTS A total of 260 and 198 patients were included before and after the intervention, respectively. Recognition of chronic kidney disease was low in both groups but demonstrated a significant increase following reporting of estimated GFR (3.9% to 12.6%, P < .001). Reporting of GFR was not associated with a significant decrease in prescription of NSAID/COX-2 medications or increased rates of correct dosing of antibiotics (P = .10 and P = .81, respectively). CONCLUSIONS Although reporting of estimated GFR was associated with improved physician recognition of CKD in elderly hospitalized patients, it did not lead to a change in physician prescribing. More extensive interventions are necessary to increase recognition and decrease medication dosing errors. Journal of Hospital Medicine 2007;2:74–78. © 2007 of Hospital Medicine.
SEX DIFFERENCES IN ROMANTIC LOVE ATTITUDES AMONG COLLEGE STUDENTS

Previous research, using factor analysis, derived seven dimensions of romantic love. We sought to address whether these dimensions differed in importance for women and men. Specifically, it was hypothesized that women would consider Marriage and Family, Traditional Romantic Behavior, Routine Activities, and Religion, and men would consider Sexual Behavior, Aberrant Sex, and Drugs as more romantic. These specific predictions were seen as consistent with the 'double standard' regarding sex, i.e., it should be more important for men, and with an earlier theory we developed in which it was argued that in addition to the 'double standard' for sex, security-related stimuli should be more important for women. The results were entirely consistent with our predictions.
Long-Circulating 15 nm Micelles Based on Amphiphilic 3-Helix Peptide-PEG Conjugates

Generating stable, multifunctional organic nanocarriers will have a significant impact on drug formulation. However, it remains a significant challenge to generate organic nanocarriers with a long circulation half-life, effective tumor penetration, and efficient clearance of metabolites. We have advanced this goal by designing a new family of amphiphiles based on coiled-coil 3-helix bundle forming peptide-poly(ethylene glycol) conjugates. The amphiphiles self-assemble into monodisperse micellar nanoparticles, 15 nm in diameter. Using the 3-helix micelles, a drug loading of ∼8 wt % was obtained using doxorubicin and the micelles showed minimal cargo leakage after 12 h of incubation with serum proteins at 37 °C. In vivo pharmacokinetics studies using positron emission tomography showed a circulation half-life of 29.5 h and minimal accumulation in the liver and spleen. The demonstrated strategy, by incorporating unique protein tertiary structure in the headgroup of an amphiphile, opens new avenues to generate organic nanoparticles with tunable stability, ligand clustering, and controlled disassembly to meet current demands in nanomedicine.
Acquired Resistance to Experimental Autoimmune Encephalomyelitis Is Independent of Vβ Usage

Abstract In Lewis rats, activated encephalitogenic T-helper cells elicit a single bout of experimental autoimmune encephalomyelitis (EAE). Recovery from EAE is marked by reduced susceptibility to disease reinduction. The purpose of this study was to determine whether a dominant expression of Vβ gene segments by encephalitogenic T cells was required for development of recovery-associated resistance. Several polyclonal and monoclonal T cell lines were derived from Lewis rats sensitized with R72-86, a synthetic peptide representing the 72- to 86-amino-acid sequence of rat myelin basic protein (RMBP). The results revealed broad heterogeneity among encephalitogenic T cells specific for R72-86 in regard to Vβ expression and CDR3 sequence. Encephalitogenic clones exclusively bearing either Vβ4 or Vβ10 TCR or polyclonal T cells bearing heterogeneous TCR transferred EAE to recipient rats and elicited resistance to EAE as revealed by subsequent challenge with guinea pig (GP)MBP in complete Freund's adjuvant (CFA). Nonpathogenic Vβ3 + and Vβ8.6 + clones specific for the 68–86 and 55–66 regions of MBP, respectively, did not elicit effective protection from EAE. These data indicate that induction of postrecovery resistance to EAE does not depend upon a particular Vβ usage.
an ILL/ELLip(op)tical po—ETIC/EMIC/Lemic/litic post® uv: ed DUCAT ion recherché repres©entation

An approximately excessive, already-much-too-full, incomprehensibly elliptical poetics of research representation, this post/conceptual writing/writhing about research explores a poetic, poemic, polemic, politic, post discourse, and describes a new grammar and rhetoric for understanding education and social science. It offers an undiscovered set of metaphors to unpack ed DUCAT ion scanty science. It is a spoken/written langue/tongue piece based on an intentionally outlandish and overwhelming form used by (some) conceptual, and POST poets. Avoiding the never-transparent language that inscribes the offalic and violent taxonomy of norm(&)al academic research Repres©entation, this writ(h)ing outlines, through a flagrantly and literally/littorally entirely tiresome, unspeakably visual and aural word conflagration, a po-etic that begins to de-inscribe the nature of metaphoric, medicalized, ventriloquizing, normative discourse of social science/education.
Myoid cells in adult human thymus.

MYOID cells are a common constituent of the thymus in lower vertebrates. Many recent electron microscopic studies of amphibia, reptiles and birds1–8, as well as foetal mammals3,9, confirm the presence within these cells of all the principal components of skeletal muscle.
Bifurcation of periodic points of some diffeomorphisms on R3

On etudie l'application F definie par F(x,y,z)=(Ax-B(y-z), Bx+A(y-z), Cx-Dx n +Ez), ou A, B, C, D et E sont des nombres reels, D¬=0 et n>1 un entier
Should Suspected Early Gallbladder Cancer Be Treated Laparoscopically

Early gallbladder cancer (EGC), defined as T1 and T2 disease, is frequently curable when completely excised without bile spillage. The objective of the present study was to determine what effect initial laparoscopic cholecystectomy has on outcome in patients with EGC. Of 89 patients referred to our institution with gallbladder cancer over an 11-year period, 26 had undergone initial laparoscopic cholecystectomy. Sixteen of the 26 patients had T1 or T2 disease and are the subjects of this report. These patients were reviewed retrospectively to assess preoperative diagnosis, intraoperative bile spillage, and outcome (recurrence and survival). In addition, the Western literature was reviewed to determine the impact of initial laparoscopic cholecystectomy on recurrence and survival of patients with EGC. Six patients had a preoperative ultrasound consistent with a mass in the gallbladder wall. Seven (44%) had documented bile spillage during the laparoscopic cholecystectomy. T stage based on the laparoscopic cholecystectomy was T1 (n = 1) and T2 (n = 15). Twelve patients underwent reexploration of whom seven underwent further radical excision (gallbladder liver bed resection and extensive lymphadenectomy). After a mean follow-up of 20.1 months (range 4 to 39 months), 69% of patients have had a recurrence or died. Three patients had a port-site recurrence. Five (71%) of seven patients with bile spillage at laparoscopic cholecystectomy have had a recurrence or died of disease. A review of the Western literature on EGC initially removed by laparoscopic cholecystectomy (including the present series) yielded 21 patients with T1 and 42 patients withT2 disease. One-year Kaplan-Meier survival (T1 = 89%, T2 = 71%) and 3-year Kaplan-Meier survival (T1 = 47%, T2 = 40%) of these patients is worse than prior reports for open cholecystectomy. An initial laparoscopic cholecystectomy with its potential for bile spillage can convert potentially curable EGC to incurable disease. Patients with preoperative findings suspicious for gallbladder cancer should undergo open exploration with intent to perform a radical cancer operation as a primary procedure if the diagnosis is confirmed intraoperatively.
Protein and Cellular Engineering with Unnatural Amino Acids

Proteins are the central functional constituents in all living organisms ranging from viruses, bacteria, yeast, and plants to mammals. All of these biopolymers that are formed by natural biosynthetic pathways are composed of a genetically determined sequence of the 20 so-called natural amino acids. The physical and chemical properties of proteins are a reflection of the side chains of each of the component amino acids. However, for some purposes it would be very desireable to have amino acids with side chains of various selected physical chemical properties, such as a keto group, a crosslinker, or a NMR probe group, incorporated into the protein. Although chemical and biochemical methods for modifying amino acid moieties in proteins have been achieved, recent successes in incorporating unnatural amino acids in vivo open entirely new avenues for determining protein functions in vivo and for the creation of unnatural proteins with novel functionalities. Several examples by employing the novel activity of unnatural amino acids have shown significant roles in both basic research and biotechnology.
Newcastle Disease Virus Infection of L Cells

Newcastle disease virus (NDV) California strain reportedly grows poorly in L cells but replicates very well in chicken embryo cells. NDV-infected L cell cultures show a characteristic virus growth curve with respect to uridine incorporation, but plaque assays of the virus produced 24 h postinfection (PI) show no infectious particles when assayed on L cell monolayers and only a very low titer on chick cell monolayers. Plasma membranes isolated and purified from infected L cells 8 h PI contain all of the major virion proteins. In addition, NDV-infected L cells show a 50% loss of H-2 antigenic activity, a phenomenon previously observed in cells productively infected with vesicular stomatitis virus. These results suggest that at least part of the normal process of NDV maturation occurs in NDV-infected L cells. Sodium dodecyl sulfate-polyacrylamide gel patterns of supernatant virus purified from cells radiolabeled with amino acids from 3 to 24 h PI in the presence of actinomycin D show that all the major NDV structural proteins are present. Electron micrographs of NDV-infected L cells show extensive virus maturation at cell membranes. It can be concluded that infection of L cells with NDV results in a normal production of virus-specific RNA, synthesis of all the major structural proteins, association of the viral envelope proteins with the L cell plasma membrane, and the loss of cell surface H-2 antigenic activity. However, most of the virus particles produced are noninfectious.
Possible decision-making preadaptations in the molly Poecilia sphenops

In many species females choose a mate from among several available males; in other species, the social system provides no apparent opportunity for making a decision among alternative suitors, and decision-making capacity is assumed to be minimal. The origins, bases, and logic of female mate choices are contentious questions with important cognitive implications. Female short-finned mollies, Poecilia sphenops, have never been observed to choose mates in the wild, where instead a male-contest social system prevails. Nevertheless they readily choose between models of males in the laboratory. Some of their decisions anticipate features found in males in more recently evolved species where the social system permits female choice. The willingness of females to choose traits in a species without such traits or evident need or opportunity for female choice in the wild is remarkable. These observations suggest that choice behavior can be latent in a species, and may direct or bias the development of behavioral preferences.
Analysis of Electrohydraulic Shock Wave Generation

Electrohydraulic Shock Wave Generation is an energy conversion process. Electrical energy stored at high voltage in a capacitor is discharged through a set of electrodes under water. The arc heats a small volume of water to a high temperature and pressure in the shock regime. This paper analyzes the relationship of the significant variables from an energy conversion perspective. The expanding pressure wave is able to fracture rock, kidney stones (lithotripsy), and resin bonded sand cores in castings. Experimental results are presented.Copyright © 2012 by ASME
Species distribution profiles of the neotropical orchids Masdevallia and Dracula (Pleurothallidinae, Orchidaceae); implications for conservation

The orchid genera Masdevallia and Dracula bear very strange and bizarre flowers. They are, however, very popular with plant enthusiasts and there is a fair amount of commercial trade in these genera. The genera belong to a sub-tribe of the orchids, the Pleurothallidinae, which otherwise mostly have small and insignificant flowers. The majority of the species of Masdevallia and Dracula have been reported from single localities and approximately two thirds of all species are found at three or fewer sites. Most genera in the sub-tribe have similar distribution patterns. Using published deforestation rates and species distribution profiles we calculate that 402 of the total 3405 pleurothallid species may have been driven to extinction by random deforestation events. It is possible that as many as 46 Masdevallia species and 14 Dracula species have already been lost and that annual extinction rates for the two genera are 1 and 0.3 species per year respectively. It has been suggested that the two genera should be protected, by listing them in CITES Appendix I. It is unlikely that embargoes on trade would change extinction rates caused by forest conversion. Such embargoes might actually hamper ex situ conservation efforts.
Bounded regions of chaotic behavior in the control parameter space of a driven non-linear resonator

Abstract We have investigated the behavior of a driven non-linear electrical resonator over a large region of the control parameter space, i.e. the amplitude and frequency of the drive voltage. In addition to features characteristic of a one-dimensional non-invertible iterated map there exist isolated regions of chaotic behavior bounded by a Feigenbaum series of period-doubling bifurcations.
Review of Launching the War on Poverty: An Oral History

An oral history presents special characteristics. These require the author/editor (and any reviewer, as well) to adapt accordingly. There inevitably are many voices: in this instance, the voices of dozens of important officials who were intimately involved in the beginnings of the “war on poverty” and its development. The task is always to avoid a rambling and unfocused discourse. The author must select and secure the cooperation of the most valuable subjects, begin with carefully crafted questions to elicit the most important information and provide continuity, and then blend the voices sufficiently to produce a coherent work. Michael Gillette has succeeded brilliantly. His Launching The War on Poverty is an insightful look into the heart of what was one of the most energetic and broad-ranging efforts in American history to deal sincerely with poverty.
Devonian conodont biogeography: Quantitative analysis of provinciality

Cluster analysis of conodont faunas from each of 17 Lower‐lower Upper Devonian zones and subzones (data as reported by Klapper and Johnson, 1980) reveal changing patterns of provinciality. Provinciality, expressed by a differentiation into western Laurussian and proto‐Tethyan biogeographic regions, is moderate in the lower Lochkovian but is low or absent in the upper Lochkovian‐lower Pragian. Provincialism returns in the Pragian and reaches its maximum development during the Emsian. Most Australian faunas are distinct from those of western Laurussia and the proto‐Tethys. Conodont faunas from suspect terranes of western North America display no unusual biogeographic affinities. Provincialism declines during the Eifelian and is only weakly developed in Givetian‐lower Frasnian faunas. Changing global sea level during the Devonian may explain the development of Devonian conodont provinciality. As proposed by Klapper and Johnson (1980), low provinciality is associated with low stands of sea level. Endemic faun...
Civic Scientist/Civic Duty

The term civic scientist has been used within the science community since 1997. The term has come to be interpreted in a variety of ways. This article, which was first prepared for the session “Cultivating the Civic Scientist” at the 2001 annual meeting of the American Association for the Advancement of Science in San Francisco on 16 February 2001, offers one perspective about the meaning of the term. It links the notion of being a civic scientist, as proposed by Neal Lane in 1997, to civic duty, which the authors define as a personal call to public service that is not necessarily linked to one's research career.
Temperature Modulation of Cerebral Depolarization during Focal Cerebral Ischemia in Rats: Correlation with Ischemic Injury

The role of cerebral depolarizations in focal cerebral ischemia is unknown. We therefore measured the direct current (DC) electrical activity in the cortex of Wistar rats subjected to transient occ...
Effect of Antioxidant Phytochemicals on the Hepatic Tumor Promoting Activity of 3,3′,4,4′-Tetrachlorobiphenyl (PCB-77)

Polychlorinated biphenyls (PCBs) have promoting activity in the liver, which may be brought about in part by the induction of oxidative stress. In this study we examined the effects of several antioxidant phytochemicals on the tumor promoting activity of 3,3',4'4-tetrachlorobiphenyl (PCB-77). Female Sprague Dawley rats were first injected with diethylnitrosamine (DEN, 150 mg/kg) and one week later the rats were fed an AIN-93 based purified diet or the same diet containing ellagic acid (0.4%), beta-carotene (0.5%), curcumin (0.5%), N-acetyl cysteine (NAC, 1.0%), coenzyme CoQ10 (CoQ10, 0.4%), resveratrol (0.005%), lycopene (10% as Lycovit, which contains 10% lycopene), or a tea extract (1%, containing 16.5% epigallocatechin-3-gallate [EGCG] and 33.4% total catechins). Rats were fed the diets for the remainder of the study. After three weeks, 2/3 of the control rats and all of the antioxidant diet-fed rats were injected i.p. with PCB-77 (300 micromol/kg) every other week for four injections. All rats were euthanized ten days after the last PCB injection. The rats that received PCB-77 alone showed an increase in the number and size of placental glutathione S-transferase (PGST)-positive foci in the liver. Lycopene significantly decreased the number of foci, while curcumin and CoQ10 decreased the size of the foci. In contrast, ellagic acid increased the number but decreased the size of the foci. All of the other phytochemicals showed only slight or no effects. Compared with the PCB-77 group, CoQ10 increased cell proliferation in normal hepatocytes, whereas the other antioxidants had no effect in either normal or PGST-positive hepatocytes. These findings show that none of the antioxidant phytochemicals produced a clear decrease in the promoting activity of PCB-77.
Photochemical hole burning of cationic porphin/saponite intercalation compounds

Abstract Intercalation compounds were synthesized from porphin derivatives with cationic substituents and saponite, which is a poly-crystalline layered silicate. The fomation of the intercalation compounds was comfirmed by X-ray diffractions and elemental analysis. We found that the porphin molecules lay their planar skeleton parallel to the silicate layer. Besides, photochemical holes can be burned at least up to 50 K and the amount of spectral diffusion is smaller in these compounds than in a typical neutral porphin/polymer system.
The design and optimization of complex NMR experiments. Application to a triple-resonance pulse scheme correlating Hα, NH, and 15N chemical shifts in 15N13C-labeled proteins

Sequence-specific assignments of the backbone resonances of proteins form the basis for further study of the structural and dynamic properties of the molecule under investigation. Traditional assignment strategies have relied on through-bond and through-space connectivities provided by homonuclear COSY, HOHAHA/TOCSY, and NOESY spectra (I-4). While very fruitful for proteins less than 10 kDA, this approach becomes difficult for larger systems, due to extensive overlap and decreasing sensitivity of experiments relying on through-bond connectivities. Recently, we have proposed a novel approach for the sequential assignment of 'H, 13C, and 15N spectra of larger proteins based on triple-resonance three-dimensional NMR spectroscopy (5, 6). These experiments exploit the relatively large one-bond J couplings between the backbone 13C and “N nuclei and between the backbone protons and the 13C and “N nuclei to which they are directly attached. Because the couplings are often large compared to pertinent linewidths for proteins less than 25 kDa in molecular weight, magnetization can be transferred between spins in an efficient manner, with the resultant spectra having good sensitivity. Moreover, because the experiments are recorded in the “3D mode,” spectral overlap is virtually eliminated. The sequential assignment of 13C-15N-labeled proteins using the triple-resonance approach is aided considerably by the HOHAHA-HMQC experiment (7). For example, the HNCA triple-resonance experiment correlates the NH and r5N chemical shifts with the intraresidue Ccu chemical shift. When combined with the HNCA experiment, the HOHAHA-HMQC experiment (which correlates “N, NH, and Ha chemical shifts) firmly establishes intraresidue correlations between pairs of “N-NH and G-Ha backbone resonances, despite significant overlap in 1 D ‘H, 15N, and 13C spectra. Linking the 15N, NH, CCX, and Ha chemical shifts is the first step in the sequential assignment process using this new approach. Unlike the triple-resonance experiments, the HOHAHA-HMQC experiment is very sensitive to the secondary structure of the protein under study, as the efficiency of magnetization transfer between NH and Ha protons depends strongly on the NH-Ha scalar couplings. These couplings are, in turn, strongly related to the backbone angle I#I and are less than 6 Hz in regions of regular a-helical secondary structure. For larger proteins rich in a-helical content, a substantial number of NH-Ha connectivities are often found to be weak or missing. In this paper a triple-
First artificial periodic inhomogeneity experiments at HAARP

Experiments involving the generation and detection of artificial periodic inhomogeneities have been performed at the High Frequency Active Auroral Research Program (HAARP) facility. Irregularities were created using powerful X-mode HF emissions and then probed using short (10 μs) X- and O-mode pulses. Reception was performed using a portable software-defined receiver together with the crossed rhombic antenna from the local ionosonde. Echoes were observed reliably between about 85 and 140 km altitude with signal-to-noise ratios as high as about 30 dB. The Doppler shift of the echoes can be associated with the vertical neutral wind in this altitude range. Small but persistent Doppler shifts were observed. The decay time constant of the echoes is meanwhile indicative of the ambipolar diffusion coefficient which depends on the plasma temperature, composition, and neutral gas density. The measured time constants appear to be consistent with theoretical expectations and imply a methodology for measuring neutral density profiles. The significance of thermospheric vertical neutral wind and density measurements which are difficult to obtain using ground-based instruments by other means is discussed.
Spectral domain optical coherence tomography for in-vivo three dimensional retinal imaging of small animals

The purpose of this study is to demonstrate the application of ultrahigh-resolution Spectral Domain Optical Coherence Tomography (SD-OCT) for non contact in vivo imaging of the retina of small animals and quantitative retinal information extraction using 3D segmentation of the OCT images. An ultrahigh-resolution SD-OCT system was specifically designed for in vivo retinal imaging of small animal. En face fundus image was constructed from the measured OCT data, which enables precise registration of the OCT images on the fundus. 3D segmentation algorithms were developed for the calculation of retinal thickness map. High quality OCT images of the retina of mice (B6/SJLF2 for normal retina, Rho -/- for photoreceptor degeneration and LH BETA T AG for retinoblastoma) and rats (Wistar for normal retina) were acquired, where all the retinal layers can be clearly recognized. The calculated retinal thickness map makes successful quantitative comparison of the retinal thickness distribution between normal and degenerative mouse retina. The capabilities of the OCT system provide a valuable tool for longitudinal studies of small animal models of ocular diseases.
A Comparison of the Readability of Abstracts with Their Source Documents.

Readability levels of 30 items from Child Development Abstracts and 30 passages from their corresponding journal articles were compared by a CAL SNOBOL computer program referenced to a cloze criterion. The difference between mean predicted cloze restoration percentage scores of 26.77 for abstracts and 30.37 for articles proved to be significant beyond the .05 level. Results supported the hypothesis that abstracts were more difficult to read than their source documents, but indicated that perhaps both types of materials were too hard for undergraduates.
Understanding Leadership through Art, History, and Arts Administration

This article presents an interdisciplinary model that weaves leadership concepts into the contextual richness of history by employing the visual arts as catalysts. An implementation of the model follows its description to highlight ways in which it can enable students to traverse conceptual boundaries among commonly diverse disciplines. The article includes an assessment of the effectiveness of this strategy by examining comments from involved students.
Genetic Divergence and Differentiation within the Western Scrub-Jay (Aphelocoma Californica)

Abstract Western Scrub-Jays (Aphelocoma californica) range throughout the western United States and Mexico and exhibit substantial geographic variation in morphology and behavior. Western Scrub-Jays are a polytypic species complex with three distinct groups (californica, woodhouseii, and sumichrasti) associated with geography and distinguished by morphology, genetics, and behavior. Until recently, the Island Scrub-Jay (A. insularis) and the Florida Scrub-Jay (A. coerulescens) were considered subspecies within the Western Scrub-Jay complex. We analyzed mitochondrial DNA sequences (control region I) to reveal the phylogenetic relationships within Western Scrub-Jays and used maximum likelihood, a Bayesian approach, and a relaxed phylogenetic approach to construct phylogenies. In addition, we used several methods to estimate divergence time between clades. Our results reveal that the interior woodhouseii group, which contains the sumichrasti subclade, and the coastal californica group have had a long and inde...
Using celerity to measure hydrological processes

The last major advance in catchment hydrology was the discovery that while headwaters respond promptly to changes in water input, much of the resulting river flow is months or years old. The classical way of testing catchment models is to use measurements that reflect celerities—the measure of how fast the storage of water responds to a perturbation—of the response to an input event such as changes in rain or snowfall. However, McDonnell and Beven point out that testing catchment models against both celerity and tracer velocity—the measure of how fast the water particles are moving—can help improve model realism and reduce uncertainties and errors.
Measuring surface currents in lakes with high spatial resolution thermal infrared imagery

[1] High spatial resolution thermal infrared satellite images acquired 38 minutes apart from Landsat ETM+ and ASTER were used to measure the surface currents and circulation in Lake Tahoe, California-Nevada, USA. Mean currents of 5–10 cm/s were measured, with maximum currents approaching 35 cm/s. The eastward transport of an upwelling surface jet was clearly apparent, with 15–30 cm/s currents. Three gyres were evident in the vector fields. The satellite image-derived surface currents and circulation patterns are consistent with surface drifter measurements acquired during a different period. These results modify the findings of an earlier study using 1.1 km AVHRR imagery, which concluded there were two counter-rotating gyres in the opposite sense to the two dominant large gyres measured in this study. The high spatial resolution and small time separation allow the surface currents and general circulation in lakes and coastal environments to be accurately quantified using the maximum cross-correlation method.
Acyltransferase activity and cytochemical localization in differentiating neuroblastoma

Abstract Acyltransferase (AT) enzyme activity was assayed biochemically and localized cytochemically in neuroblastoma monolayers to investigate the possible role of the enzyme in neuroblastoma differentiation and neurite extension. Treatment of cultures for 1 day with serum-free medium or Ro20-1724, a cyclic AMP phosphodiesterase inhibitor, induced neurite outgrowth but did not alter acyltransferase activity. Treatment for 4 days with dexamethasone or Ro20-1724 induced neurite outgrowth and a doubling of enzyme activity per cell. Chromatographic separation of lipid classes indicated that dexamethasone enhanced triacylglyceride synthesis. Acyltransferase was localized in mitochrondria of neuroblastoma cells. The results show that 1) dexamethasone stimulates the storage lipid metabolic pathway in neuroblastoma cells and 2) increased acyltransferase activity is concomitant with dexamethasone-induced morphological differentiation. However, AT activity and neurite extension may not be causally related.
On the convergence of gradient methods under constraint

The mathematical programming problem discussed is the convergence of a certain popular type of gradient procedure for maximizing a function under inequality constraints. An example shows that convergence to a solution need not always occur, and a theorem shows that under certain circumstances the gradient method does converge.