cssi/SciSciGPT-SciSciNet huggingface dataset:
Characterization of a cytochrome P450 from di(2-ethylhexyl) phthalate-treated rats which hydroxylates fatty acids.

Abstract A cytochrome P450 was purified from liver microsomes of rats treated with di(2-ethylhexyl) phthalate (DEHP). DEHP is a member of a group of structurally diverse compounds which have been classified as peroxisome proliferators and are inducers of cytochromes P450 which hydroxylate lauric acid and other fatty acids. The P450 isolated from DEHP-treated rats (P450 DEHP ) was observed to have a M r value of 51 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a maximum absorbance of 452 nm in its reduced carbon monoxide bound state. The amino terminal residue for P450 DEHP was alanine and an 18-amino acid segment at the N-terminal region was identified. The N-terminal amino acid for the P450 4A1 from clofibrate-treated rats is methionine and alignment of the N-terminal segment of the P450 DEHP with P450 4A1 indicated that the first four amino acids were absent. There were two amino acid differences between the two P450s in this 18-amino acid segment; in P450 DEHP an alanine and a phenylalanine were substituted for serines in P450 4A1. The P450 DEHP was found to catalyze the hydroxylation of several saturated fatty acids, having the highest turnover activity with laurate (82.1 nmol 12-OH-laurate formed/ min/nmol P450). Myristate, palmitate, and stearate were also metabolized but at decreasing rates. Cytochrome b 5 stimulated laurate 12-hydroxylation 10-fold in a reconstituted system. Laurate was not metabolized at its 11-carbon atom; however, the longer chain length fatty acids were metabolized at the (ω−1)-carbon atom in addition to the ω-carbon atom. A polyclonal antibody to the P450 DEHP recognized three protein bands in liver microsomes from control and DEHP-treated rats on Western blot analysis, but only two protein bands from phenobarbital-treated rats.
Role of the liver in regulation of carbohydrate metabolism in hagfish, Eptatretus stouti

Abstract 1. 1. Hepatectomized hagfish survived 5–30 days without administration of glucose. 2. 2. In contrast to other vertebrates, hepatectomized hagfish experienced only a transient hyperglycemia, as did the sham-operated animals. 3. 3. Plasma amino nitrogen levels were unchanged after hepatectomy. 4. 4. These data, together with activities of glucose-6-phosphatase in various organs, suggest that the liver of this primitive animal does not serve the same regulatory function in carbohydrate metabolism as in higher vertebrates.
Genetic Determinant of Lithium Ion Distribution: I. An in Vitro Monozygotic-Dizygotic Twin Study

Research in pharmacogenetics has provided evidence that individual variation in rate of metabolism of various drugs is genetically controlled. To evaluate the possibility of a genetic determinant of lithium ion distribution, a monozygotic (MZ)-dizygotic (DZ) twin study method was used. Red blood cell (RBC) lithium ion concentrations were assessed for ten MZ and seven DZ twin pairs following a 24-hour incubation in vitro. The distributions of intrapair difference scores of MZ twin pairs and DZ twin pairs were relatively nonoverlapping, with MZ intrapair difference scores being smaller on the average. A heritability index of 0.85, calculated as a function of intrapair difference scores, indicated that a substantial genetic factor is operative in RBC uptake of lithium ion.
Letter by asosingh et Al regarding article, "circulating endothelial progenitor cells in patients with eisenmenger syndrome and idiopathic pulmonary arterial hypertension".

To the Editor: Diller and colleagues1 report a decrease in circulating progenitor cells and a trend of increased colony-forming units endothelial-like cells in idiopathic arterial hypertension compared with healthy controls. This is an interesting article in light of other reports, including 1 by our group, which report that circulating CD34+/CD133+ and colony-forming units endothilial-like cells are increased in idiopathic pulmonary arterial hypertension.2,3 Given this disparity, clarification of technical aspects related to the way in which …
What corporate America is teaching about ethics

Executive Overview Many corporations are convinced that an ethical corporate culture is related to strategic advantage. To establish this culture, corporations have worked at establishing codes of ethical conduct. Now, as corporations complete the establishment of codes, more and more are turning to ethics training as the next step in incorporating ethical considerations into decision-making. What constitutes ethics training varies widely. Corporations conducting ethics training generally include messages from CEOs or other managers, discuss codes of ethics, and provide mechanisms for reporting problems. Corporate classes on ethics also include case studies, guidelines for ethical decisions, decision-making frameworks, and cognitive intervention. This article examines the current state of the objectives, extent, and content of ethics training. Implications for management are discussed.
The thermodynamic landscape of testosterone binding to cytochrome P450 3A4: ligand binding and spin state equilibria.

Human cytochrome P450 (CYP) 3A4 catalyzes the oxygen-dependent metabolism of greater than 60% of known drugs. CYP3A4 binds multiple ligands simultaneously, and this contributes to complex allosteric kinetic behavior. Substrates that bind to this enzyme change the ferric spin state equilibrium of the heme, which can be observed by optical absorbance and electron paramagnetic resonance (EPR) spectroscopy. The ligand-dependent spin state equilibrium has not been quantitatively understood for any ligands that exhibit multiple binding. The CYP3A4 substrate testosterone (TST) has been shown previously by absorbance spectroscopy to induce spin state changes that are characteristic of a low spin to high spin conversion. Here, EPR was used to examine the equilibrium binding of TST to CYP3A4 at [CYP3A4] > KD, which allows for characterization of the singly occupied state (i.e., CYP3A4·TST). We also have used absorbance spectroscopy to examine equilibrium binding, where [CYP3A4] < KD, which allows for determination ...
Construction of a Gene Bank of Streptococcus lactis Plasmid pLM2001 Deoxyribonucleic Acid in Escherichia coli

Abstract Plasmid pLM2001, which is essential for the fermentation of lactose by Streptococcus lactis LM0232, was isolated and cut into eight fragments with restriction endonuclease Eco RI. The deoxyribonucleic acid fragments ranged in size from approximately .8 to 10.3 kilobases as determined by agarose gel electrophoresis. Eco RI-restricted pLM-2001 deoxyribonucleic acid was shotgun cloned into the single Eco RI site of the multifunctional Escherichia coli-Streptococcus sanguis shuttle vector, pSA4, insertionally inactivating the chloroamphenicol resistance gene. Following transformation of the deoxyribonucleic acid into Escherichia coli HB101, 242 transformants containing chimeric plasmids were detected by their resistance to tetracycline and failure to grow in the presence of chloramphenicol. Plasma deoxyribonucleic acid from 98 transformants was cleaved with Eco RI and analyzed by agarose gel electrophoresis for the presence of pLM2001 inserts. Clones were obtained, which individually contained each of the eight fragments. In addition, a series of clones containing various combinations of the fragments was obtained. The availability of a system for cloning and rapidly screening for fragments of Streptococcus lactis deoxyribonucleic acid under conditions where deletion of passenger or vector deoxyribonucleic acid does not occur will facilitate studies designed to isolate and characterize metabolically important genes carried by plasmids from the group N streptococci.
Adrenoleukodystrophy: survey of 303 cases: biochemistry, diagnosis, and therapy

Adrenoleukodystrophy (ALD) is a genetically determined disorder associated with progressive central demyelination and adrenal cortical insufficiency. All affected persons show increased levels of saturated unbranched very-long-chain fatty acids, particularly hexacosanoate (C26:0), because of impaired capacity to degrade these acids. This degradation normally takes place in a subcellular organelle called the peroxisome, and ALD, together with Zellweger's cerebrohepatorenal syndrome, is now considered to belong to the newly formed category of peroxisomal disorders. Biochemical assays permit prenatal diagnosis, as well as identification of most heterozygotes. We have identified 303 patients with ALD in 217 kindreds. These patients show a wide phenotypic variation. Sixty percent of patients had childhood ALD and 17% adrenomyeloneuropathy, both of which are X-linked, with the gene mapped to Xq28. Neonatal ALD, a distinct entity with autosomal recessive inheritance and points of resemblance to Zellweger's syndrome, accounted for 7% of the cases. Although excess C26:0 in the brain of patients with ALD is partially of dietary origin, dietary C26:0 restriction did not produce clear benefit. Bone marrow transplant lowered the plasma C26:0 level but failed to arrest neurological progression.
Review: BNL Tokamak graphite blanket design concepts☆

Abstract The BNL minimum activity graphite blanket designs are reviewed, and three are discussed in the context of an experimental power reactor (EPR) and commercial power reactor. Basically, the three designs employ a 30 cm or thicker graphite screen. Bremsstrahlung energy is deposited on the graphite surface and re-radiated away as thermal radiation. Fast neutrons are slowed down in the graphite, depositing most of their energy, which is then radiated to a secondary blanket with coolant tubes, as in types A and B, or removed by intermittent direct gas cooling (type C). In types A and B, radiation damage to the coolant tubes in the secondary blanket is reduced by one or two orders of magnitude, while in type C, the blanket is only cooled when the reactor is shut down, so that coolant cannot quench the plasma.
Strong nonlocal effects in a Tokamak perturbative transport experiment

A finite but small injection of carbon into the TEXT tokamak edge induces significant temperature perturbations throughout the plasma. Large, rapid temperature decreases are observed in the outer third, while temperatures in the inner third promptly begin to rise. The effects cannot be reproduced with transport coefficients that are functions only of local thermodynamic variables. A large increase in ${\ensuremath{\chi}}_{e}$ must occur within 100 \ensuremath{\mu}s in the outer region, and ${\ensuremath{\chi}}_{e}$ must simultaneously begin to decrease in the interior. Increases in local density fluctuation levels coincide with the increase in ${\ensuremath{\chi}}_{e}$.
The Y-architecture: yet another on-chip interconnect solution

In this paper, we propose a new on-chip interconnect scheme called Y-architecture, which can utilize the on-chip routing resources more efficiently than traditional Manhattan interconnect architecture by allowing wires routed in three directions (0/spl deg/, 60/spl deg/, and 120/spl deg/). To evaluate the efficiency of different interconnect architectures, we assume mesh structures with uniform communication demand and develop a multi-commodity flow (MCF) approach to model the on-chip communication traffic. We also extend the combinatorial MCF algorithm of N. Garg and J. Konemann (Proc. 39th Annual Symp. on Foundations of Comp. Sci., pp. 300-309, 1998) to compute the optimal routing resource allocations for different interconnect architectures. The experiments show that: (1) compared with the Manhattan architecture, the Y-architecture demonstrates a throughput improvement of 30.7% for a square chip. The throughput of the Y-architecture is only 2.5% smaller than that of the X-architecture. (2) A chip with the shape of a convex polygon produces better throughput than a rectangular chip: For Y-architecture, a hexagonal chip provides 41% more throughput than a squared chip using the Manhattan architecture. For Manhattan architecture, a diamond chip achieves a throughput improvement of 19.5%, over the squared chip using the same interconnect architecture. (3) Compared with Manhattan architecture, the Y-architecture reduces the wire length of a randomly distributed two pin net by 13.4% and the average wire length of Y-architecture is only 4.3% more than that of the X-architecture.
Nitrosamines and other carcinogens as agents of protein denaturation

Les auteurs montrent que les composes cancerogenes hydrosolubles, l'acide tannique, le phenol, la diethyl-et dimethylnitrosamine, la thioacetamide, le carbamate d'ethyl et la thiouree sont des agents puissants de denaturation de proteines. La precipitation produite par ces agents peut etre inhibee, inversee ou accrue par divers reactifs de groupes sulfhydryles. Ces recoupements, ainsi que d'autres experiences sur l'effet de l'uree sur la precipitation par la dimethylnitrosamine, indiquent que le mecanisme de la formation des aggregats moleculaires consiste dans l'etablissement de ponts -S-S- intermoleculaires, probablement renforces par des liaisons intermoleculaires d'hydrogene.
Category of loop spaces of open subsets in Euclidean space

has been studied in several recent papers (e.g. [l, 2, 5, 6, 91) in situations where the potential function V is singular, in the sense that it is defined and C’ only on an open subset U of Euclidean k-space Rk and not on the whole of Rk. If E = WGT2(R, Rk) is the Sobolev space of T-periodic functions from R to Rk and E(U) is the subset of E of functions which map into U, then the topology of E(U) plays a crucial role in these studies. In particular, the knowledge that the Lusternik-Schnirelmann category of E(U) is infinite, when used in conjunction with min-max methods, implies the existence of infinitely many critical points. Another subset E,,(U), which consists of those functions in E(U) which take the origin to a base point in U, plays a dual role. First of all, in problems concerning the existence of geodesics in U from one subset A of U to another B of U (see e.g. [3]), the category of E,(U) plays a role. Secondly, the general inequality cat E(U) 2 cat E,,(U) (see [6]), when U is connected and simply connected, can be applied to show that cat E(U) = cat E,,(U), thus providing a tool for computing cat E(U). The topological analogue of E(U) is the space of free loops AU = C’[S’, U] of continuous maps from the circle S’ to U and the analogue of E,(U) is the space of based loops RU which consists of maps in AU which take a base point in S’ to a base point in U. AU has the same homotopy type as E(U) and S2U has the same homotopy type as E,,(U). Thus, homotopy type invariants (e.g. category) of E(U) and E,(U) may be studied through AU and SZU, respectively. The following classical theorem of Serre [l l] is useful in this regard and is stated in terms of a general space X.
Synthesis, characterization, and subcellular localization studies of amino acid-substituted porphyrinic pigments

Stopping cancer in its path occurs when photosensitizers (PSs) induce apoptotic cell death after their exposure to light and the subsequent formation of reactive oxygen species. In pursuit of our hypothesis that mitochondrial localizing PSs will enhance the efficacy of the photosensitizing process in photodynamic therapy, since they provoke cell death by inducing apoptosis, we synthesized and characterized tetraphenylporphyrins (TPPs) that are substituted at the paraphenyl positions by two amino acids and two fluoro or hydroxyl groups, respectively. They were prepared according to the Lindsey-modified Adler-Longo methodology using trifluoromethanesulfonylchloride (CF 3 SO 2 Cl) as a catalyst instead of trifluoroacetic acid. The use of CF 3 SO 2 Cl yielded cleaner products in significantly higher yields. During the synthesis, not only the yields and work-up procedure of the TPPs were improved by using CF 3 SO 2 Cl as a catalyst, but also a better means of synthesizing the precursor dipyrromethanes was tested by using indium(III) chloride. Column chromatography, HPLC, and NMR spectroscopy were used to separate and characterize the di-amino acid-dihydroxy, or difluoro-substituted porphyrins and to ascertain their purity before subcellular localization studies were carried out. Studies using androgen-sensitive human prostate adenocarcinoma cells LNCaP revealed that certain amino acid substituted porphyrins that are positively charged in the slightly acidic medium of cancer cells are very useful in shedding light on the targets of TPPs in subcellular organelles of cancer cells. Although some of these compounds have properties of promising photosensitizers by revealing increased water solubility, acidic properties, and innate ability to provoke cell death by apoptosis, the cell killing efficacy of these TPPs is low. This correlates with their subcellular localization. The di-amino acid, di-hydroxy substituted TPPs localize mainly to the lysosomes, whereas the di-fluoro-substituted TPPs are trapped in the plasma membrane. Only a pheophorbide derivative recently synthesized in our laboratory localized to the mitochondria of LNCaP cells, which are at the center of cell death as is reflected in their key role during apoptosis, thus reassuring our attempts toward rational drug design.
The influence of weather on annual yields of honey

The influence of weather conditions on the average yield of honey in one apiary over a period of 30 years in the UK has been studied. In highly significant multiple regression equations weather variables accounted for over 80% of the variation in annual average honey yield. Weather in March, May and June had the major effects. Implications and applications of the equations are considered.
The Dialectics of Deeds and Words: Or Anti‐the‐Antis (and the Anti‐Antis)

Modern cultural theory suffers from a diffuseness so great that it seems to subvert discourse within our scholarly community. Our theories range from sociobiology, at one extreme, through various kinds of materialism and old-fashioned functionalism to theories, at the other extreme, that locate the study of culture in language and meaning. One might hope that the protagonists of each doxology would illuminate our profession with constructive debate, but they speak past each other in a confusion of tongues; there is much talking but little dialogue. Offhand, one might say that our future seems very bad, yet we can draw some comfort from our one tried and tested anthropological truth, which is that: Things are never the way they seem. Indeed, we make our livings by showing that what seems to be one thing is actually something else, an alchemy that allows us to find in ritual either sublimated sex or a source of fertilizer. In this critical spirit, I will attempt to locate within the chaos of contemporary theory a different direction that, paradoxically, will call anthropology back to its center. One axis of distinction between anthropological schools is the degree to which they take account of the human mind, and I will confine my remarks to two persuasions at polar extremes of difference on this subject: materialism and certain directions in postmodernism and interpretation. Some materialists say that there is no such thing as "mind." There is, rather, only the human brain, into which external stimuli flow and from which behavioral responses emanate. As for this brain, one doesn't have to know what's inside it or how it works-just what goes in and what comes out. What comes out is whatever gives the biggest bang for the least effort, which is more elegantly known as "operant conditioning." And since culture is defined by the same materialists as "learned and shared behavior," it follows that when enough people get the same bangs and respond in the same way, culture is born-but John Stuart Mill said it better in his views on the greatest good for the greatest number 150 years ago. And 42 years ago, I took experimental psychology with my old friend and Columbia College classmate, Marvin Harris; he became a believer in the Gospel according to Thorndike, and I, reacting against behaviorism, became a devotee of Sigmund Freud. Isaiah Berlin sorted career thinkers into two types: Foxes and Hedgehogs. The Foxes are people who have many ideas, folks like Clifford Geertz and myself. Our trouble is that after a while nobody knows where we stand, which only be-
Elastic scattering of neutrons from N15

Abstract Angular distributions for the elastic scattering of neutrons from N15 have been measured in the neutron energy interval between 440 and 1960 keV, corresponding to the excitation energy region from 2.71 to 4.33 MeV in N16. The distributions were measured by observing the recoil spectra from a N15-filled proportional counter irradiated by neutrons. Total cross sections were determined by normalizing relative cross sections obtained from the integrated angular distributions to published total cross-section data. In addition to a previously observed resonance at 1960 keV, a resonance formed by l=1 neutrons has been found at a neutron bombarding energy of 940 keV, corresponding to an excitation energy of 3.37 MeV in N16. For neutron energies below 900 keV, the angular distributions are isotropic, while in the energy region 1000–1900 keV the shapes of the distributions change little with energy.
The Nature and Effects of Technological Change over the Industry Life Cycle

Abstract This paper estimates quality and cost innovations in the early automobile, personal computer, rigid disk drive, computer monitor, and computer printer industries using industry-level data on firm numbers, price, quantity, and quality and an equilibrium model of industry evolution. The results challenge the notion that new industries experience quality innovation early on and cost innovation later on. In the microelectronics industries the rate of quality improvement does not diminish over time. In the automobile industry, even though the rate of quality improvement is highest early on, the profitability of quality advantages is highest later on. Journal of Economic Literature Classification Numbers: L10, L63, O31.
Influence of Amount of Feed Intake and Forage Physical Form on Digestion and Passage of Prebloom Alfalfa Hay in Dairy Cows

Abstract Six Holstein cows were fed prebloom alfalfa hay in long, chopped, and pelleted form (60:40 hay:grain ratio) in a replicated 3×3 Latin square design (21-d periods) conducted in early (wk 3 to 11) and middle (wk 20 to 32) lactation and during the dry period to attain three feed intakes for determination of digesta kinetics. Dry matter intakes averaged 3.75, 2.93, and 1.95% of body weight across intakes. There was no effect of forage physical form on intake or milk production. Chewing activity, ruminal fermentation patterns, and milk fat percent were similar for long and chopped hay treatments. Digestibility of organic matter was reduced 7.9% at high versus low intake and 3.2% when pelleted rather than long hay was fed. Ruminal retention time of ytterbium applied to hay declined with increasing feed intake. There was no effect of chopping or grinding on rumen dry matter fill or retention time of ytterbium applied to hay. Effects of forage physical form on retention time and ruminal fill appear small when low fiber alfalfa is fed. Digestibility depression associated with fine grinding of high quality alfalfa was related to depressed ruminal digestion rate. Digestibility depression at high intake was related to shortened ruminal residence time.
Racial differences in a high-risk colorectal cancer referral population: a single-center experience

Background Multiple studies have shown that colorectal cancer (CRC) disparities exist between African Americans and Caucasians. African Americans have higher CRC incidence and mortality than Caucasians [1,2]. Furthermore, African Americans present with more advanced CRC [3] and at younger ages [4]. However, little is known about the impact of hereditary CRC syndromes in African Americans on these disparities. In the University of Chicago Cancer Risk Clinic, we see a diverse referral population for evaluation of hereditary syndromes based on personal or family history of CRC. We sought to compare clinical characteristics of our African American and Caucasian patients to determine if differences exist in a high-risk CRC referral population. Method We retrospectively collected data on self-reported African American and Caucasian individuals who were referred for a personal or family history of CRC from 1992-2010. Available clinical characteristics including number of individuals, number of families (probands with family members who followed-up in our clinic), personal or family history of CRC, age at cancer onset, and number of individuals who underwent genetic testing for APC or mismatch repair genes were collected. Pedigrees were reviewed to determine Revised Bethesda, Amsterdam II and PREMM1,2 scores. Statistical analysis included Student’s t-test for continuous variables and Pearson’ sc hi-square for categorical variables. Comparison of independent proportions was done using z-ratios. Results
Customer service 101: a refresher for us all

While we all work in the field of technology, at the heart of what're do is customer service. However this is a skill that we seldom take the time to reflect on or improve. While many consider customer service to be common sense, it still warrants a regular review of the basics. Using the book DELIVERING KNOCK YOUR SOCKS OFF SERVICE by Ron Zemke, this paper will review the basics of customer service to help us all ensure that we are on the correct path.
Assessing influence on regression coefficients in generalized linear models

SUMMARY Suggested diagnostics for influence on the estimated regression coefficients in a generalized linear model have generally approximated the effect of deleting a single case. We apply the local influence method of Cook (1986) to assess the effect of small perturbations of the data, including the vector of responses, case weights, explanatory variables, and the components of one case. The resulting diagnostics allow one to check for different kinds of influence, and may give insight into its workings. Two examples illustrate some of the diagnostics.
The Effect of High-Temperature-Short-Time Heating of Concentrated Milk Upon its Heat Stability

Summary 1. High-temperature-short-time heating of concentrated milk increased its heat stability to a maximum and then decreased it. With no holding time the heat stability increased with rise in temperature up to the point of initial coagulation. Factors which controlled the attainment of maximum heat stability were the time and temperature of forewarming the raw and of heating the concentrated milk and the solids content of the concentrate. The greatest heat stability was obtained when the raw milk was heated at 120° C. (248° F.) for 4 minutes and the concentrate to 150° C. (302° F.) with no holding period. 2. Great differences in heat stability resulted from changes in the time and temperature of forewarming. Samples of raw milk were forewarmed at temperatures of 65° C. (149° F.) to 120° C. (248° F.) and held from zero to 10 minutes. After concentration these samples were heated to temperatures of 95° C. (203° F.) to 150° C. (302° F.) and held from zero to 20 minutes. 3. The most desirable heat treatment is not always the one that gives maximum stability, since the effect of the heat treatment on the body and color of the milk being processed must also be considered. Heating of the milk after concentration permits a close control of the body of the sterilized product without the use of stabilizing salts. 4. High-temperature-short-time heating the concentrated milk to attain the desired heat stability offers the possibility of modifying the commercial sterilizing methods by reducing the length of the conventional “cooking” period in the can. This would, of course, require the use of previously sterilized cans and a highly sanitary technic. Thus an evaporated milk of superior color and flavor could be produced.
QSPR for Physical Properties of cata-Condensed Benzenoids Using Two Simple Dualist-Based Descriptors

Dualists of benzenoids are a special type of graphs that have as vertices the centers of hexagons and as edges the pairs of condensed rings. Catafusenes (cata-condensed benzenoids) have acyclic dualists. Codes of catafusenes with h benzenoid rings start from one end of a dualist and consist of digits 0 (indicating linear annelation, angle of 180° between two adjacent edges) and 1 or 2 for kinks (120° or 240° angles) with the convention of choosing the lowest number formed from these h−2 digits. A shape parameter (n) for the dualist consists of the number of adjacent zeros in the code plus 1. It is shown in the present communication that many molecular properties of catafusenes depend mainly on n, whereas most bulk properties depend mainly on h. Monoparametric or biparametric correlations in terms of the simple integer parameters n and/or h are presented for molecular properties (energy of the p-band in electronic absorption spectra, ionization potentials, electron affinities, hardness and softness) and bu...
Oscillatory density-of-states of Landau bands in a two-dimensional lateral surface superlattice

Abstract A new oscillatory phenomenon is observed in the magneto-capacitance between the high mobility two-dimensional electron gas in a GaAs/AlGaAs heterostructure and a metal grid gate of 200nm periodicity. The observed minima reflect the minima in the density-of-states of Landau bands resulting from removal of the Landau level degeneracy by the grid gate potential. A model calculation is carried out and the results agree with the experimental observation.
Use of three-dimensional catheter guidance and trans-esophageal echocardiography to eliminate fluoroscopy in catheter ablation of left-sided accessory pathways.

Background: Newer technologies such as three-dimensional mapping and echocardiography can decrease x-ray exposure during catheter ablation. Many right-sided tachycardias can now be ablated without fluoroscopy. Left-sided tachycardias, however, have not yet been ablated using a zero fluoroscopy approach. Objective: This study sought to examine the utility of trans-esophageal echocardiography (TEE) in providing adequate imaging as an alternative to fluoroscopy for transseptal puncture. When combined with NavX guidance (St. Jude Medical, St. Paul, MN, USA), fluoroscopy may not be necessary. Methods: Ten pediatric patients with supraventricular tachycardia (SVT) had accessory pathways mapped to the left side. Right atrial and coronary sinus geometries were created using NavX. Once a left-sided pathway was confirmed, a transseptal puncture was performed. A guide wire was placed in the SVC and confirmed by TEE. A transseptal sheath and dilator were advanced over the wire and positioned with TEE guidance so that the tip of the dilator was tenting the fossa ovalis. A transseptal needle was advanced across the fossa. Left atrial location of the needle tip was confirmed on TEE by saline contrast injection. The sheath and dilator were advanced over the needle with continuous pressure monitoring and TEE. Once the sheath was appropriately positioned, the ablation was completed using NavX guidance. Results: All patients had acutely successful ablations and none required the use of fluoroscopy. Number of cryo lesions ranged from five to 19, with a mean of 9. Mean procedure time was 4.4 hours, with a range of 3.2 hours to 7.2 hours. There were no complications. One patient had recurrence. Conclusions: Three-dimensional mapping combined with TEE shows potential for eliminating fluoroscopy use during catheter ablation.
Benefit finding in fathers of childhood cancer survivors: a retrospective pilot study

There is a growing literature examining positive outcomes following traumatic experiences. Although the diagnosis of a child with cancer poses extraordinary challenges for the family, awareness is growing that such a life-changing event can be a catalyst for positive growth. The current mixed methods study investigated benefit finding in fathers (N = 25) of childhood cancer survivors. Benefit finding included positive changes resulting from adversity. Participants completed a benefit finding measure and an interview describing their experience and benefits from the challenges faced during their child's cancer journey. Findings indicated that fathers endorsed high levels of benefit finding (mean = 4.1 out of 5) specifically in personal growth, spiritual change, and relationships with others. Our study extends the literature by examining how their child's cancer journey contributed to specific domains of paternal benefit finding. These results support the use of a positive psychology framework for understanding effects of a child's cancer diagnosis on caregivers.
The Role of Publicly Provided Electricity in Economic Development: The Experience of the Tennessee Valley Authority, 1929–1955

I study the impacts of one of the largest regional development projects in American History, the Tennessee Valley Authority (TVA), on a variety of economic outcomes. The TVA has been noted as an example of how to develop a region's water power potential to stimulate growth. In what follows, I show using a county-level panel dataset, that the TVA had little impact on economic growth in the South. I attribute these results to the institutional history of the TVA and the contractual agreements it signed in an effort to expand its service territory. “…as a pebble dropped in a pond causes ripples to flow outward to the surrounding shores, the influence of TVA'slow rates flows outward to surrounding areas…” TVA's Influence on Electric Rates 1965
Extrinsic airway compression secondary to pulmonary arterial conduits: MR findings

Abnormal enlargement or malposition of any vascular structure or mass adjacent to the airway can cause extrinsic airway compression. In children with previous surgery for congenital heart disease, mass effect from prosthetic devices or alteration in the anatomic position of normal structures can lead to extrinsic airway compression. Because many children have complex medical problems after cardiac surgery, wheezing may be attributed to cardiac causes and airway compression may not be investigated. Furthermore, the distal airway compression seen in these children often is not visualized on chest radiographs. MR imaging can be useful in evaluating extrinsic airway compression in these patients. We present the MR imaging of two patients with symptomatic extrinsic airway compression secondary to pulmonary arterial conduits.
A morphometric analysis of the hypertrophy of experimental liver cirrhosis

The objective of this study was to better elucidate the composition of the hypertrophic cirrhotic liver. We induced cirrhosis with hypertrophy in rats by simultaneous treatment with CCl4 and phenobarbital (PB) and devised a hierarchy of structure applicable to the sampling and morphometric analysis of untreated and PB-treated control livers and of cirrhotic livers. Our analysis demonstrated that the hepatomegaly attributable to cirrhosis is virtually the total result of an increase in the specific volume (ml/100 g body weight) of the non-parenchyma, most of which is connective tissue and vascular lumen volume. Inconsequential to the hepatomegaly but statistically significant were the volumetric increases found in the following parenchymal compartments: hepatocyte nucleus, Kupffer/endothelial cell nucleus, Ito cell nucleus and cytoplasm, and bile canaliculus. The change in the hepatocyte nucleus is the result of an increase in size rather than in number. Sinusoidal space is the only compartment that showed a significant decrease. This study shows the practicality and usefulness of applying morphometric methods to cirrhotic liver.
Myocardial suppression in vivo by spin locking with composite pulses

Improved myocardium-blood contrast by myocardial suppression resulting from T1 rho-weighting in contrast-enhanced, gradient-echo, bright-blood cine images, acquired at 1.5T, is shown. In the standard images, blood has twice the intensity of muscle. In similar T1 rho-weighted images, it has 3-4 times the intensity of muscle. A composite spin-lock pulse before each observation pulse provides T1 rho-weighting. A typical pulse was: 90y-135x-360x-135x-90(-y) with element durations: 0.84, 1.26, 8.12, 1.26, and 0.84 ms. The tolerance of this composite pulse to shimmering and frequency errors allows spin locking with comparatively weak RF and therefore low specific absorption rate (SAR). Initial clinical evaluation on patients with poor ventricular function demonstrates both a qualitative and quantitative improvement in delineation of myocardial borders.
An analysis and the effects of class-action lawsuits

Abstract Because class-action lawsuits are different in nature from other kinds of lawsuits, previous studies that examined the effect of lawsuits on corporate defendants without distinguishing between class-action lawsuits and non-class-action lawsuits missed an insight that separating the data could have provided. This study analyzes class-actions and contrasts the effects of class-action lawsuits with non-class-action lawsuits between 1990 through 1994. The results show that while the markets, generally, react negatively to the stocks of defendants on the announcement of non-class-action lawsuits, these reactions are limited to a smaller event-window. On the other hand, reactions to the announcement of class-action lawsuits are larger in magnitude and tend to occur over a larger event-window. In addition to being in accord with stylized beliefs on the effects of class-action, these findings also (1) explain why researchers need to analyze the effects of class-action lawsuits using larger event-windows, (2) explain the need to develop different strategies to address the different types of lawsuits, e.g. non-class-action and class-action lawsuits, and (3) offer an insight into strategies that the practitioner could develop to limit the devastating effects of class-action on the firm.
Characterization of the Absolute Crystal Polarity across Twin Boundaries in Gallium Phosphide Using Convergent-Beam Electron Diffraction.

The measurement of absolute crystal polarity is crucial to understanding the structural properties of many planar defects in compound semiconductors. Grain boundaries, including twin boundaries, in the sphalerite lattice are uniquely characterized by the crystallographic misorientation of individual grains and the direction of the crystal polarity in domains adjoining the grain boundary. To evaluate crystal polarity in gallium phosphide (GaP), asymmetrical interference contrast in convergent-beam electron-diffraction (CBED) patterns was used to ascertain the nature and direction of polar bonds. The direction of the asymmetry in the electron diffraction reflections was correlated with the crystal polarity of a sample with known polarity. The CBED technique was applied to determine the polar orientation of grains adjoining Σ = 3 coherent and lateral twin boundaries in polycrystalline GaP.
Total absorption of light by gratings in grazing incidence: a connection in the complex plane with other types of anomaly.

An explanation is given for the effect of total absorption of light in grazing incidence by a sinusoidal grating, recently reported by us. The behavior of the zeros of both the first and the zeroth diffraction orders is studied numerically in the complex α plane. A link between the grating anomaly, non-Littrow perfect blazing, and plasmon excitation in relief metallic gratings is established. A total analysis of the behavior of the zeroth-order zero in grazing incidence is carried out, including groove depth, wavelength, and profile dependences.
Positive and negative effects of neurotrophins on the isthmo-optic nucleus in chick embryos

The survival of neurons in the developing isthmo-optic nucleus (ION) is believed to depend on the retrograde transport of trophic molecules from the target, the contralateral retina. We now show that ION neurons transport nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3) retrogradely and that BDNF and NT-3 support the survival of ION neurons in vivo and promote neurite outgrowth in vitro. Surprisingly, NGF enhanced normal developmental cell death in vivo in a dose-dependent way. These findings show that increased levels of NGF can have adverse effects on differentiated neurons. The negative effect of NGF could be mimicked by intraocular injection of antibodies that block binding of neurotrophins to the 75 kd neurotrophin receptor (p75). These data implicate a role for the p75 receptor in NGF's neurotoxicity and indicate that this receptor is involved in the mechanism by which ION neurons respond to BDNF and NT-3 in the target.
Automatic Correction of the 3D Orientation of the Brain Imagery

Classification of human brain pathologies can be guided by the estimation of the departure of 3D internal structures from the normal bilateral symmetry. However symmetry based analysis can't be precisely carried out when the 3D brain orientation is misaligned, a common occurrence in clinical practice. In this paper, a technique to automatically identify the symmetry plane and correct the 3D orientation of volumetric brain images in a cost effective way is developed. The algorithm seeks the best sampling strategies to realign 3D volumetric representation of the brain within scanner coordinate system. The inertia matrix is computed on the sampled brain, and the principle axes are derived from the eigenvectors of the inertia matrix. The technique is demonstrated on MR and CT brain images and the detected symmetry plane that is orthogonal to the principle vectors is provided. A spatial affine transform is applied to rotate the 3D brain images and align them within the coordinate system of the scanner. The corrected brain volume is re-sliced such that each planar image represents the brain at the same axial level.
Synthesis of glycosylated zinc (II) 5,15-diphenylporphyrin and zinc (II) 5,10,15,20-tetraphenylporphyrin analogs using Cu-catalyzed azide-alkyne 1,3-dipolar cycloaddition reactions

Abstract Carbohydrate porphyrin conjugates (CPCs) have gained attention for their ability to serve as water soluble catalysts and therapeutics for photodynamic therapy (PDT). However, the synthesis of these compounds continues to be a significant challenge. In this Letter we detail the direct synthesis of a series of glycosylated porphyrins prepared directly from Zn(II) 5,15-[ p -(ethynyl)-diphenyl] or Zn(II) 5,10,15,20-[ p -(ethynyl)-diphenyl] porphyrins and per- O -acetylated sugar azides using copper catalyzed 1,3-dipolarcycloaddition reactions. The highest yields were achieved using a copper (II) catalyst reduced in situ, and we were able to achieve average yields greater than 90% per cycloaddition reaction.
"My Name Is Money": Name Choices and Global Identifications at a South-Chinese University.

Recent communicative language teaching reforms in China have focused on the creative use of English in classroom activities. In response to these reforms, many students have chosen to use English names in classroom, online, and professional contexts, particularly with foreign teachers. Based at a university closely linked to national teaching reforms, this article examines the reasons why university students in China select their English names, and the roles foreign and Chinese teachers play in these choices. Data include interviews with student and teacher participants, student journals from a classroom project on English names, and multiple discussions at a student English club. The article reveals that many students choose English names that are associated with foreign English-speaking communities, but other students chose names that represent their individuality, playfulness, and creativity. The article ends with a discussion of how English name choices complicate the separation of local and global sp...
Internal bremsstrahlung spectrum of 139Ce.

The internal bremsstrahlung spectrum which accompanies the electron capture decay of {sup 139}Ce to the first excited state of {sup 139}La has been measured in coincidence with the nuclear gamma ray which deexcites that state. The measured intensity above 42 keV is found to be (1.070{plus_minus}0.024) times that predicted by the recent calculations of Suri{acute c} {ital et} {ital al}. The {ital Q}{sub EC} value is found to be 264.6{plus_minus}2.0 keV. {copyright} {ital 1996 The American Physical Society.}
The Nlrp3 inflammasome promotes age-related thymic demise and immunosenescence.

Summary The collapse of thymic stromal cell microenvironment with age and resultant inability of the thymus to produce naive T cells contributes to lower immune-surveillance in the elderly. Here we show that age-related increase in ‘lipotoxic danger signals' such as free cholesterol (FC) and ceramides, leads to thymic caspase-1 activation via the Nlrp3 inflammasome. Elimination of Nlrp3 and Asc, a critical adaptor required for inflammasome assembly, reduces age-related thymic atrophy and results in an increase in cortical thymic epithelial cells, T cell progenitors and maintenance of T cell repertoire diversity. Using a mouse model of irradiation and hematopoietic stem cell transplantation (HSCT), we show that deletion of the Nlrp3 inflammasome accelerates T cell reconstitution and immune recovery in middle-aged animals. Collectively, these data demonstrate that lowering inflammasome-dependent caspase-1 activation increases thymic lymphopoiesis and suggest that Nlrp3 inflammasome inhibitors may aid the re-establishment of a diverse T cell repertoire in middle-aged or elderly patients undergoing HSCT.
RATE OF GLYCOGENOLYSIS IN THE ESTROGEN-PRIMED RAT UTERUS IN VITRO.

Uterine horns were suspended in Krebs-Ringer bicarbonate solution aerobically for different periods and were then removed and frozen, while the control horns were frozen immediately. The percentage of glycogen remaining in the uterus decreased for approximately the first 15 min at a rate of 2.24 min-1 following apparent first order kinetics. The initial decrease in glycogen was independent of the presence of an energy source in the medium. Following the initial glycogen loss, the rate of loss changed. When an energy source was available, either glucose or lactate, there was no further significant decrease in the percentage of glycogen remaining for at least 135 min. If no energy source was available, the percentage of glycogen remaining continued to decrease, but at a slower rate, 0.45 min-1, and still followed apparent first order kinetics. When uteri were pre-incubated in the absence of glucose and then placed into glucose media with or without insulin, a greater net synthesis of glycogen occurred with ...
Near-field acoustics of clustered rocket engines

This paper presents an approach for the prediction and characterization of the near-field acoustic levels from closely spaced clustered rocket engines. The calculations are based on the method proposed by Eldred wherein the flow field from the clustered rockets is divided into two zones. Zone 1 contains the isolated nozzles that produce noise independently and extends up to a distance where the individual flows completely mix to form an equivalent single nozzle flow. Zone 2 is occupied by the single mixed stream starting from the station where the jets merge. The acoustic fields from the two zones are computed separately on the basis of the NASA-SP method developed for a single equivalent nozzle. A summation of the spectra for the two zones yields the total effective sound pressure level for the clustered engines. Under certain conditions of nozzle spacing and flow parameters, the combined sound pressure level spectrum for the clustered nozzles displays a double peak. Test cases are presented here to demonstrate the importance of hydrodynamic interactions responsible for the double peak in the sound spectrum in the case of clustered rocket nozzles, and the role of ground reflections in the case of noninterfering jets.