cssi/SciSciGPT-SciSciNet huggingface dataset:
Characterization of a family of high-molecular-weight plasminogen activators secreted by a lung tumor cell line.

In an earlier publication (Harvey, et al. (1982) J. Biol. Chem., 257, 5645–5651) the discovery of a family of unusually large molecules with plasminogen activator activity in the conditioned medium of a human lung cancer cell line was reported. These molecules are related to urokinase (uPA) by functional and immunological criteria. We have now purified two representatives of this glycoprotein family of M r 900 000 (PA900) and M r (PA660). While these could be fractionated into subspecies exhibiting size and charge differences, reduction yielded in all cases two predominant chains of 70 and 40 kDa, respectively. Since the amino acid composition of the subfractions was identical, we conclude that the heterogeneity is due to demonstrated differences in glycosylation. The amino acid composition of the unreduced species and of the major reduced chains differed from that of 55 kDa uPA. These enzymes are active toward the substrate, plasminogen, as well as toward the uPA-specific synthetic substrate, Spectrozyme UK, and these activities are inhibitable by diisopropylphosphorofluoridate (DFP). Treatment of PA660 with [ 3 H]DFP resulted in the incorporation of 1.4 mol of DFP into 1 mol of enzyme, suggesting the presence of a single active site. The label was quantitatively recovered in a 21 kDa fragment in a reduction experiment. This fragment also demonstrated immunological reactivity with antiurokinase. It is postulated that PA660 is composed of five or six pairs of the 70 and 40 kDa chains, and of a single uPA-like entity. All of these chains are linked by disulfide bonds. Whether larger portions of uPA are also present in this molecule, is not yet clear. By electron microscopy, PA900 shows a filamentous structure, while PA660 is predominantly globular. The occurrence of large uPA-like activators in extracts of human colon carcinomas that crossreact with monospecific antibody against uPA, is discussed.
The water permeability of the monoolein/triolein bilayer membrane

Abstract The water permeability of the lipid bilayer can be used as a probe of membrane structure. A simple model of the bilayer, the liquid hydrocarbon model, views the membrane as a thin slice of bulk hydrocarbon liquid. A previous study (Petersen, D. (1980) Biochim. Biophys. Acta 600, 666–677) showed that this model does not accurately predict the water permeability of the monoolein/ n -hexadecane bilayer: the measured activation energy for water permeation is 50% above the predicted value. From this it was inferred that the hydrocarbon chains in the lipid bilayer are more ordered than in the bulk hydrocarbon liquid. The present study tests the liquid hydrocarbon model for the monoolein/triolein bilayer, which has been shown to contain very little triolein in the plane of the membrane (Waldbillig, R.C. and Szabo, G. (1979) Biochim. Biophys. Acta 557, 295–305). Measurements of the water permeability coefficient of the bilayer are compared with predictions of the liquid hydrocarbon model based on measurements of the water permeability coefficient of bulk 8-heptadecene. The predicted and measured values agree quite closely over the temperature range studied (15–35°C): the predicted activation energy is 11.1±0.2 kcal/mol, whereas the measured activation energy for the bilayer is 9.8±0.7 kcal/mol. This close agreement is in contrast with the monoolein/ n -hexadecane results and suggests that, insofar as water permeation is concerned, the liquid hydrocarbon model quite closely represents the monoolein/triolein bilayer.
mHMM (multivariate hidden Markov model) application in studying BRD4 and JMJD6 function cooperatively on promoter-proximal polymerase-II (Pol II) pausing release

Bromodomain-containing protein 4 (BRD4) is a positive regulatory component of P-TEFb complex, which is composed of CDK9 and Cyclin T1/2. P-TEFb complex promotes elongation by phosphorylating serine 2 of the Pol II carboxyl-terminal domain (CTD), which induces gene transcription transition from initiation to elongation. Our complex purification revealed that BRD4 is one of the components in the core complex of Jumonji C domain-containing protein 6 (JMJD6). Based on the observation of their physical interaction, we propose that JMJD6 and BRD4 function in promoter-proximal Pol II pausing release and transcriptional elongation. We first tested JMJD6 and BRD4 effects on Pol II pausing release by doing Pol II chromatin immunoprecipitation coupled with high throughput sequencing (ChIP-seq) and global nuclear run-on coupled with sequencing (Gro-seq) in cells transfected with control siRNA or siRNAs specifically targeting on JMJD6 or BRD4. Interestingly, both ChIP-seq and Gro-seq analysis revealed that knock-down of JMJD6 or BRD4 caused Pol II pausing on promoter regions of genes positively-regulated by both proteins as indicated by the increase of Pol II traveling ratio compared to control siRNA sample. Furthermore, genome-wide profiling of JMJD6 and BRD4 binding sites through ChIP-seq revealed that these two proteins might regulate Pol II pausing release through their binding on distal-regulatory elements. And the mHMM (multivariate Hidden Markov Model) mathematical model is a powerful method of learning chromatin states model, correlating biological functions with large-scale functional datasets. In our study, we apply this model to study and predict the regulatory patterns correlated regions existing in the observed combination of target factors and histone marks that might effects on the Pol II pausing release mechanism. And we found that BRD4 & JMJD6 are characterized to co-localize together with Pol-II on gene's promoter region, which suggests that they function together on Pol-II promoter-proximal pausing release by binding on promoter regions. And the TR (traveling ratio) test show and confirm that the promoter-proximal Polymerase-II (Pol II) are influenced and paused by siBRD4 and siJMJD6 effect.
Cash prizes and mail survey response rates: A threshold analysis

In a study involving the mailing of some 3,150 questionnaires, the ability of six kinds of incentives to augment survey responses was tested against a no-incentive control condition. Two of the incentives were small prepaid monetary amounts (25¢ and $1.00), while the remaining four consisted of the opportunity for respondents to win cash prizes valued at either $50, $100, $150, or $200. The use of such cash prizes enabled an approximate test of the just-noticeable-difference principle in terms of both its absolute and differential threshold hypotheses. The 25¢ and $1.00 incentives yielded response rates that were significantly larger than that of the control group. No confirmation of the differential threshold hypothesis was evidenced, at least over the range of cash prizes employed in the present study. In contrast, the absolute threshold hypothesis received support. Suggestions for further research in this area were also identified.
Dynamic contact angles and contact angle hysteresis

Abstract Contact angles have been measured as a function of the three-phase-boundary velocity. Large velocity effects observed with other techniques were not seen using the plate method. It is possible to relate the dependence of contact angles on velocity to surface heterogeneity.
Atomic layer deposition of hafnium nitrides using ammonia and alkylamide precursors

Abstract We use DFT to investigate an atomistic mechanism for the ALD of hafnium nitride films grown using Hf[N(CH3)2]4 and NH3. We find a ligand-exchange mechanism similar to those thought to occur in the ALD of HfO2 using the same Hf source and H2O. Although the Hf[N(CH3)2]4 half-reaction at NH* sites has a barrier similar to that of reaction with OH* sites, the barrier for the NH3 half-reaction on the Hf [ N ( CH 3 ) 2 ] x ∗ terminated surface is significantly larger than for reaction between H2O and Hf [ N ( CH 3 ) 2 ] x ∗ . Thus, the NH3 half-cycle will be prone to oxygen incorporation into Hf–nitride from residual H2O.
Abstract 4936: Network signatures of survival in glioblastoma multiforme

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults and also the most aggressive, with a median survival time of approximately 1 year. Differences in age and pathology have long been recognized as key factors in determining prognosis, and, more recently, comprehensive mRNA profiling has been undertaken to establish the molecular basis underlying prognosis. Though early mRNA expression-based gene sets represented unbiased queries into molecular differences in gliomas, they only uncovered differences in survival ex post facto 1, 2 . Newer gene sets capitalize upon advances in technology, yet they suffer for their unwieldy size and ambiguous biological meaning 3 . Though the myriad gene sets proposed share little overlap with each other, recent work has demonstrated that the use of interaction networks can consolidate these differences. To determine the molecular basis of prognostic differences in GBM directly, we employed an existing computational framework, CRANE, to exhaustively search protein interaction networks and identify molecular signatures distinguishing short-term ( 635 days) survivors of GBM in The Cancer Genome Atlas gene expression microarray dataset. Using CRANE, we identified a 50 gene subnetwork signature of survival in GBM, which we validated in an independent dataset of 91 patients (80% classification accuracy). We further hypothesized that the use of interaction networks consolidates variation in mRNA expression into more stable features at higher phenotypic levels. To test this hypothesis, we examined protein expression levels of the 50 network targets in an independent cohort of 16 patients (10 patients: survival 18 months) using label-free proteomics. Of the 17 network targets identified in common with our 50 subnetwork signature genes, 8 were significantly differentially expressed between short-term and long-term survivors, and expression levels of 3 of the proteins (STAT3, Calnexin, and HSPA9) predicted phenotype (LTS vs. STS) with 75% or more accuracy (12 or 13 correct out of 16). Our conclusion is that data integration using interaction networks can drive discovery of a stable subnetwork signature exhibiting clear differences in protein expression. This manageable subset of proteomic targets will prove invaluable in the design of cost-effective clinical assays (e.g. IHC) suitable for retrospective analysis from FFPE tumor tissue in existing biobanks, as well as for prospective studies predicting patient survival - a much desired endpoint for clinicians and patients alike. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4936. doi:1538-7445.AM2012-4936
Response to Letter Regarding Article, “AT2 Receptor Activation Induces Natriuresis and Lowers Blood Pressure”

We thank Drs Maiolino, Naso, and Calo for their kind recognition of our study.1 We are delighted to learn of the evidence from the human model of Bartter and Gietelman syndromes that AT2 receptors (AT2Rs) are activated via angiotensin signaling. Indeed, in both of these human syndromes, there is marked activation of the renin–angiotensin system (RAS) associated with hypotension, to which AT2Rs may contribute by direct vasodilation and natriuresis. Numerous studies in experimental animals have shown that AT2Rs oppose the pressor actions of angiotensin II (Ang II) via AT1Rs and lower blood pressure, especially in the presence of AT1R blockade.2–9 Indeed, AT2R stimulation lowers blood pressure predominantly under circumstances in which the RAS is activated10–13 by increasing pressure natriuresis.11,13 It is likely that the depressor and hypotensive effects of AT2R activation …
Transcriptome analysis of two buffalograss cultivars

Buffalograss [Buchloe dactyloides (Nutt.) Engel. syn. Bouteloua dactyloides (Nutt.) Columbus] is a United States native turfgrass species that requires less irrigation, fungicides and pesticides compared to more commonly used turfgrass species. In areas where water is limited, interest in this grass species for lawns is increasing. While several buffalograss cultivars have been developed through buffalograss breeding, the timeframe for new cultivar development is long and is limited by a lack of useful genetic resources. Two high throughput next-generation sequencing techniques were used to increase the genomic resources available for buffalograss. Total RNA was extracted and purified from leaf samples of two buffalograss cultivars. ‘378’ and ‘Prestige’ cDNA libraries were subjected to high throughput sequencing on the Illumina GA and Roche 454 Titanium FLX sequencing platforms. The 454 platform (3 samples) produced 1,300,885 reads and the Illumina platform (12 samples) generated approximately 332 million reads. The multiple k-mer technique for de novo assembly using Velvet and Oases was applied. A total of 121,288 contigs were assembled that were similar to previously reported Ensembl commelinid sequences. Original Illumina reads were also mapped to the high quality assembly to estimate expression levels of buffalograss transcripts. There were a total of 325 differentially expressed genes between the two buffalograss cultivars. A glycosyl transferase, serine threonine kinase, and nb-arc domain containing transcripts were among those differentially expressed between the two cultivars. These genes have been previously implicated in defense response pathways and may in part explain some of the performance differences between ‘Prestige’ and ‘378’. To date, this is the first high throughput sequencing experiment conducted on buffalograss. In total, 121,288 high quality transcripts were assembled, significantly expanding the limited genetic resources available for buffalograss genetic studies. Additionally, 325 differentially expressed sequences were identified which may contribute to performance or morphological differences between ‘Prestige’ and ‘378’ buffalograss cultivars.
The synchrotron-self-Compton process in spherical geometries. II - Application to active galactic nuclei

Observational implications and constraints on spherical nonthermal synchrotron self-Compton models with applications to AGNs are discussed. The Compton optical depth of the source and the synchrotron optical depth are considered, and plausible electron distributions are discussed. The alpha(0x), alpha(rx), and alpha(0r) system of comparing the fluxes in different energy bands is related to the nonthermal models, and sample spectra are presented that show the spectral features the models can produce. The models are applied to radio-quiet AGNs. It is shown that the infrared and X-ray continua of the AGNs can be produced by nonthermal processes.
Evidence for major differences in ribosomal subunit proteins from Plasmodium berghei and rat liver.

Abstract Purified polysomes were isolated in high yield from the erythrocytic stages of the rodent malaria parasite, Plasmodium berghei , and from rat liver. Proteins extracted from the ribosomal subunits derived from these polysomes were fractionated and their number and molecular weights were estimated by two-dimensional polyacrylamide gel electrophoresis. Plasmodial small ribosomal subunits contained 30 proteins ranging in apparent molecular size from 11.7 to 40.7 kDa, while large subunits contained 35–36 proteins ranging from 12.1 to 42.6 kDa. None of these parasite proteins was shared by the two subunits nor altered in electrophoretic mobility by radioiodination. Rat liver 40 S ribosomal subunit proteins numbered 30 and ranged from 9.2 to 37.5 kDa, while liver 60 S subunits contained 41–43 proteins with apparent molecular sizes of 10.3–45.2 kDa. Coelectrophoresis of trace amounts of radioiodinated P. berghei ribosomal subunit proteins and stainable quantities of liver proteins demonstrated that most of these 139 parasite and host ribosomal proteins possessed different two-dimensional electrophoretic mobilities under the conditions of this study. Based upon a comparative analysis of P. berghei and rodent ribosomal RNA and these data, it was concluded that parasite and host ribosomes contain distinct ribosomal RNAs and ribosomal proteins.
Definitive doline characteristics in the Clarksville quadrangle, Tennessee

Two random samples of dolines in the Clarksville quadrangle, Tennessee (selected on the basis of the presence or absence of natural ponds), were statistically compared on the bases of long-axis orientation, vectorial mean long-axis orientation, agreement with systematic joint sets, and length of doline long axis versus doline mean width. The two doline samples are not members of the same population of doline long-axis orientations, nor do the two samples have the same preferred long-axis orientations. Both samples have different vector mean long-axis orientations, and the vector mean long-axis orientations of dolines without natural ponds is statistically significant. The polymodal preferred doline long-axis orientations correlate with the three systematic joint sets in the study area, particularly the N20° to 40°E and N10° to 30°W sets. Both doline samples belong to the same population of length/mean-width ratios and are related allometrically in the form L = 1.656 W 1.024 .
Norepinephrine plus Phentolarnine Improves Regional Blood Flow during Experimental Low Cardiac Output Syndrome

A complication of cardiac surgical procedures is postoperative low cardiac output syndrome. Treatment with norepinephrine plus phentolamine (N + P) is beneficial, but the effect of these agents on regional organ blood flow has not been evaluated. Therefore, in 6 dogs with long-term instrumentation, pentobarbital was infused to simulate low cardiac output (32 + 10% of the conscious control level). Infusions of N + P at 0.2, 0.5, and 1.0 microgram/kg/min restored cardiac pump performance to conscious control levels. Regional blood flows, determined with tracer-labeled microspheres, were substantially reduced in the low cardiac output state but increased to values not markedly different from control levels in all organs studied except stomach fundus during infusion of N + P. The pressure-work index, an indirect measure of myocardial oxygen consumption, did not increase to more than the conscious level except at the highest dose. The data demonstrate that simultaneous infusion of N and P is capable of successfully improving cardiac pump performance with restoration of vital organ perfusion and without evidence of excessive myocardial oxygen consumption.
Waveform design considerations for modulated pulse lidar

Techniques have been developed to mitigate many of the issues associated with underwater imaging in turbid environments. However, as targets get smaller and better camouflaged, new techniques are needed to enhance system sensitivity. Researchers at NAVAIR have been developing several techniques that use RF modulation to suppress background clutter and enhance target detection. One approach in particular uses modulation to encode a pulse in a synchronous line scan configuration. Previous results have shown this technique to be effective at both forward and backscatter suppression. Nearly a perfect analog to modulated pulse radar, this technique can leverage additional signal processing and pulse encoding schemes to further suppress background clutter, pull signals out of noise, and improve image resolution. Additionally, using a software controlled transmitter, we can exploit this flexibility without the need to change out expensive hardware. Various types of encoding schemes were tested and compared. We report on their comparative effectiveness relative to a more conventional non-coded pulse scheme to suppress background clutter and improved target detection.
Parental Strategies in Contrasting Cultural Settings: Families in México and “El Norte”

A “culturally relevant pedagogy” has been recommended to enhance the achievement of Latino students in American schools. In practice, this pedagogy is often based on a view of the home culture as static and in conflict with mainstream culture. The present study compares the child-rearing practices and values of Mexican immigrants raising their children in the United States with those of their siblings who are raising children in Mexico. The study contributes to the theories of culture, documenting the dynamic nature of cultural practices on both sides of the border and examining the implications of cultural change of different types for practice in language minority education.
The Effects of Exercise on Food Intake and Body Fatness: a Summary of Published Studies

Exercise has well-recognized health benefits, including reduction in risk factors for cardiovascular disease and type 2 diabetes. However, the extent to which exercise influences energy regulation and facilitates a reduction in body fat is less clear. This review summarizes published studies on the effects of different amounts of exercise on body fatness, energy intake, and food preferences in humans. The results show consistent effects of exercise on body fatness in the absence of prescribed dietary change, with a progressive loss of body fat associated with higher exercise energy expenditures in both men and women. In part, these effects appear to be mediated by a spontaneous reduction in hunger associated with participation in exercise. Insufficient data are available on whether there are changes in food preferences and taste perception that influence energy balance through macronutrient selection, so further studies in this area are needed.
B cells pay a price

Mice deficient in the Ung uracil-DNA glycosylase have an increased level of uracil in their genome, consistent with a major role of Ung counteracting U:A base pairs arising by misincorporation of dUMP during DNA replication. A complementary uracil-excising activity apparently acts on premutagenic U : G lesions resulting from deamination of cytosine throughout the genome. However, Ung specifically processes U : G lesions targeted to immunoglobulin variable (V) genes during somatic hypermutation and class-switch recombination. Gene-targeted Ung -/- null mice remained tumour-free and showed no overt pathological phenotype up to ∼12 months of age. We have monitored a large cohort of ageing Ung -/- mice and, beyond 18 months of age, they had a higher morbidity than Ung +/+ controls. Post-mortem analyses revealed pathological changes in lymphoid organs, abnormal lymphoproliferation, and a greatly increased incidence of B-cell lymphomas in older Ung-deficient mice. These are the first data reporting the development of spontaneous malignancies in mice due to deficiency in a DNA glycosylase. Furthermore, they support a specific role for Ung in the immune system, with lymphomagenesis being related to perturbed processing of antibody genes in germinal centre B cells.
Surface nucleated transformation kinetics in 2- and 3-dimensional finite systems

Abstract Phase transformation kinetics in 2- and 3-dimensional finite systems occurring by nucleation and growth, and in which nucleation occurs solely at the boundary edge, are considered. Attention is limited to the case where nucleation is completed prior to growth. Expressions are derived for the area fraction of material transformed as a function of time, X(t), which are exact within a probabilistic framework. Numerical results are obtained for X(t), and they are discussed and analyzed.
Warm Climate Surprises

The present climate, which falls between the last ice age and the next, is relatively stable. New data on past climate change, however, indicates that the climate is capable of undergoing abrupt changes from one mode to another. In his Perspective, Overpeck describes the current research into the history of climate change and how it might influence our thinking about future climate variation.
Elimination of insulin-like activity present in certain batches of crude bovine serum albumin by trypsin treatment

Abstract By treatment with trypsin, insulin-like activity in certain batches of crude (Fraction V) bovine serum albumin was eliminated. Trypsin, 10 mg, was added to 100 ml of 5% albumin solution containing 0.154 m NaCl, pH 7.4. The mixture was incubated first at 37°C for 1 h and then at 0–4°C for 16 h. Subsequently, trypsin was inactivated with 10 mg of soybean trypsin inhibitor, and the solution was supplemented with 5 mg each of penicillin G and streptomycin. When isolated rat epididymal fat cells were suspended in a 2% solution of the trypsin-treated albumin, they showed low basal activities for glucose transport and phosphodiesterase. The trypsin-treated albumin did not significantly interfere with the actions of insulin on glucose transport, phosphodiesterase, and lipolysis. Furthermore, the treated albumin did not detectably affect the lipolytic action of epinephrine.
Limitations in Usefulness of Single Dose Intermediate Acting Insulin: A Rapid Response Pattern in Some Type I Diabetics

ABSTRACT Ten Type I insulin-dependent diabetics who were receiving single daily injections of intermediate acting insulin were studied to assess time-response characteristics of this therapy on 24-hour profiles of both glucose and free insulin. Nine of ten patients had undetectable postprandial levels of C-peptide. All patients had insulin antibodies typical of chronically treated Type I diabetes. Mean peak free insulin levels occurred four hours post injection with free insulin rising from 12.3 ± 1.6 μU/ml to 26.5 ± 1.4 μU/ml; p
Using United States Medical Licensing Examination® (USMLE) Examination Results to Predict Later In-Training Examination Performance Among General Surgery Residents

Objective To examine the relationship between and predictive nature of United States Medical Licensing Examination ® (USMLE) Step 1, Step 2, and American Board of Surgery In-Training Examination (ABSITE) postgraduate year (PGY) 1-5 scores from 2 general surgery programs from 1999-2009, with a goal of discerning how Step 1 and Step 2 scores should be used in resident selection and screening. Design A descriptive, retrospective, correlational study was conducted using data from existing program records. Setting Two accredited Midwestern community teaching hospital general surgery residency programs. Participants Data were collected from the records of N=34 residents completing the programs in the years 1999-2009. Results Although a statistically significant correlation exists between USMLE Step 1 and ABSITE PGY 3 scores, Step 2 scores were more highly correlated to ABSITE scores from all years of residency training. In both hierarchical and simple regression models, Step 2 scores were superior in predicting ABSITE PGY 1-5 scores, with the strongest predictability for PGY 3 and PGY 5 scores. Conclusions USMLE Step 1 scores showed limited utility in predicting later ABSITE scores whereas Step 2 scores were more predictive of all years of ABSITE scores. These findings should prompt additional research into the relationship between examination performances at different points along the general surgery education continuum. In the mean time, general surgery program directors and faculty might do well to examine the relationships between Step 1 and Step 2 scores and ABSITE scores in their own programs to evaluate the usefulness of considering either score when ranking potential residents for selection into a program.
INTOR divertor in a realistic 2-D geometry

Abstract The INTOR divertor operation has so far been modeled only in a simplified rectangular geometry, which omitted some of the important features of the actual INTOR divertor. Recently, the PLANET plasma transport code upgrades have allowed us to model the open magnetic geometry of the INTOR divertor realistically, in particular, with regard to the trapped neutral gas region between the two separatrices and the open geometry. The effect of this neutral gas build-up on the plasma density, temperature, and the energy loss has been examined. The neutral hydrogen interaction with the plasma, and the interaction of the resulting charge-exchange neutrals with the walls is discussed. The power flux profiles at the plates were computed under the assumption of constant radial transport coefficients. It was found that the change in these profiles from the x- point to the plates is due mostly to the compression in the poloidal magnetic field. The heat loads on the neutralizer plate and first wall have been characterized, and the erosion of the divertor walls and the neutralizer plates is discussed.
Echocardiography in the Cardiac Transplant Recipient

Despite the widespread use of echocardiography in the cardiac allograft recipient, the clinical usefulness of this practice is not well defined. In this article, the authors review the spectrum of echocardiographic findings in the adult heart transplant patient. Appreciation of typical alterations from "normal" allows the transplant physician to identify clinically significant changes and to avoid unnecessary invasive procedures based on misinterpretation of these differences. Though abnormalities of systolic and diastolic function correlate with episodes of acute rejection, the primary diagnostic usefulness of echocardiography in acute rejection is guiding the endomyocardial biopsy. Additionally, echocardiography has found a role as a supplement to invasive angiography in the diagnosis of cardiac allograft vasculopathy.
Counting of Ion Channels on a Membrane Patch Aided by Patch-Clamp Fluorometry

Direct estimation of the number of channels on a membrane path is important for channel biophysics. It is a classical question and has been addressed elegantly by previous studies. Especially, pioneering researchers took the advantage of fluctuations in membrane conductance caused by ion channels opening and closing. The number of channels, the single-channel current, and the probability of the channel opening can be obtained using the method of non-stationary or stationary fluctuation analysis. Here, we developed a method to count the number of channels by simultaneous electrical recording of channel opening and optical recording of the fluorescence from the green fluorescent protein(GFP) tagged to the channel. Based on the number of channels and the macroscopic current, we first tuned this method using the cyclic-nucleotide gated (CNG) channel, of which the single channel conductance and open probability are well characterized. Then we applied the I-F relationship to the hyperpolarization-activated, cAMP-regulated HCN channel, of which the estimation of single channel conductance has been controversial. We estimated that the number of channels on a piece of membrane patch could read 10,000 to 20,000 and the single channel conductance for mHCN2 channel is about 1.82 pico Siemens.
Glycogen concentration and DNA synthesis in isoproterenol-stimulated salivary glands☆

Abstract Following injection of IPR there is an initial decrease and then a marked increase in concentration of salivary gland glycogen correlated with an increased incorporation of 14C-glucose into glycogen. Several experiments have indicated that there is a close relationship between elevated glycogen levels and subsequent DNA synthesis, since any induced decrease in peak glycogen concentration results in a decreased incorporation of 3HTdR into DNA. Furthermore, after a second injection of IPR, DNA synthesis is depressed until high levels of glycogen are restored.
Characterization of soft-sediment deformation: Detection of cryptoslumps using magnetic methods

Many workers have explored anisotropy of magnetic susceptibility (AMS) of sediments as an indicator of deformation. Several studies have used deflection of the eigenvector associated with the minimum in susceptibility, V3, as a criterion for deformation. We examine the AMS record of a well-exposed slump and find that although demonstrable deformation can occur without deflecting the V 3 directions, an oblate AMS fabric is transformed into a triaxial fabric during initial deformation. Transformation of the fabric from oblate to triaxial appears to be highly correlated with an increase in natural remanent magnetization scatter, whereas deflection of the V 3 axes is not. We suggest that subtle soft-sediment deformation can be detected by using AMS fabric.
Corticosterone binding by rat brain cytosol.

Significant quantities of corticosterone were associated with macromolecules of the brain cytosol following intrathecal administration of [3H]corticosterone to adrenalectomized rats. Fifteen times more steroid was found associated with proteins from adrenalectomized rats than from control animals or adrenalectomized animals pretreated with corticosterone. Pretreatment of adrenalectomized rats with 11-dehydrocorticosterone, Cortisol and cortisone decreased the amount of [3H]corticosterone found associated with protein, whereas progesterone, oestradiol and testosterone did not interfere with the association of [3H]corticosterone with macromolecules of the cytosol. Further evidence for protein-steroid interaction was obtained by incubating [3H]corticosterone (B), [3H]cortisol (F), or 11-[3H]deoxycortisol (S) with brain cytosols. The degree of binding was in the order B > F > S.
Double Quantum 1H MAS NMR Studies of Hydrogen-Bonded Protons and Water Dynamics in Materials

Two-dimensional double quantum (DQ) 1H MAS NMR was used to investigate different proton environments in a series of alkali (Na, K, Rb, Cs) [Nb6O19]8- Lindqvist salts, with the water and hydrogen-bound intercluster protons being clearly resolved. Through the analysis of the DQ 1H NMR spinning sideband pattern, it is possible to extract both the mean and distribution of the motionally averaged intramolecular homonuclear 1H-1H dipolar coupling for the different water environments and the intercluster protons. Motional order parameters for the water environments were then calculated from the averaged dipolar couplings. The influence of additional intermolecular dipolar couplings due to multispin interactions were simulated and discussed.
High-pressure techniques for discovering and re-hydrogenation of metal hydride materials

This overview will highlight features of the main classes of hydrogen storage materials based on their crystal structures. High-pressure techniques have proven to be a useful approach to rapidly discover light-weight, high-capacity hydrogen storage materials in the solid state. Focus will be on three different materials systems; magnesium-based transition metal hydrides, alanates and borohydrides, their crystal structures and properties, prepared by high-pressure sintering, high-energy ball milling or in a cubic anvil.
Molecular Level Friction As Revealed with a Novel Scanning Probe

Friction at the molecular level is examined with a novel scanning probe microscope that observes the onset of energy dissipation and adhesive forces simultaneously. Friction is monitored by measuring the damped vibrational amplitude of an oscillating probe tip, analogous to shear-force feedback commonly used in near-field scanning optical microscopes. A mechanically stable interfacial force sensor is used to measure normal forces at the tip independently and decoupled from the lateral forces, allowing one to observe friction from the early stages of the purely adhesive tensile regime to the latter stage of repulsive compression. Measurements on model lubricant silane and alkanethiol self-assembled monolayers indicate that friction dramatically increases with the strength of adhesive interactions between the tip and the monolayers. These adhesive interactions occur over an appreciable (7 ± 1 A) displacement range, suggesting tensile reorientation of the lubricant chains and subsequent energy losses due to ...
The Impact of CEO Turnover on Equity Volatility

A change in executive leadership is a significant event in the life of a firm. Our paper investigates a potentially significant consequence of a CEO turnover: a change in equity volatility. We develop several hypotheses about how CEO changes might affect stock price volatility, and test these hypotheses using a sample of 872 CEO changes over the 1979-1995 period. We find that volatility increases following a CEO turnover, even for the most frequenttype, when a CEO leaves voluntarily and is replaced by someone from inside the firm. Ourresults indicate that forced turnovers, which are expected to result in large strategy changes, increase volatility more than voluntary turnovers. Outside successions, which are expected to result in a successor CEO with less certain skill in managing the firm's operations, increase volatility more than inside turnovers. We also document a greater stock-price response to earnings announcements around CEO turnover, consistent with more informative signals of value driving the increased volatility. Controls for firm-specific characteristics indicate that the volatility changes cannot be entirely attributed to factors such as changes in firm operations, firm size, and both volatility change and performance prior to the turnover.
GABAergic subsensitivity of dorsal raphe neurons in vitro after chronic benzodiazepine treatment in vivo

Previous studies have shown that chronic benzodiazepine treatment reduces the in vivo sensitivity of dorsal raphe neurons (DRN) to microiontophoretically applied gamma-aminobutyric acid (GABA). We have examined sensitivity of DRN in vitro using a modified midbrain slice technique which allows side-by-side analysis of slices from control and chronic diazepam-treated rats. GABA sensitivity of raphe neurons was reduced in slices from rats treated for 3 weeks with diazepam, compared to control sensitivity. Thus, GABA subsensitivity following chronic diazepam treatment appears to be dependent on changes intrinsic to the midbrain area.
Review Essay Ethnicity, Identity and Nationality in Latin America

This essay surveys recent scholarship on the history of ethnicity in Latin America and the Atlantic World, exploring ways in which Jewish, Japanese and Middle Eastern minorities have transacted nationhood, identity and integration. This historiography of ethnicity offers compelling paths for understanding how transnational identities are negotiated. These include the analysis of patterns of slaveholding by Jewish communities on both sides of the Atlantic and the ways in which these communities understood blackness; the use of memory in understanding experiences of immigration; the relationships between national foreign policy and domestic ethnic politics; and the extent to which the issues of negotiating identity and asserting ethnicity are shared by a variety of immigrant ethnic groups. Together, this body of literature reflects the substantial ways in which ethnic histories interplay with other facets of national histories and with the process of historical analysis.
Patterns of antidepressant use in community practice

Abstract Computerized pharmacy records from a large staffmodel health maintenance organization were used to examine patterns of antidepressant use by primary care physicians and psychiatrists. Based on timing of prescription refills, patients treated by psychiatrists were more likely than those treated in primary care to continue medication for more than 30 days (35% vs 25%, p p p p
In Vitro Degradation of an Aromatic Polyanhydride with Enhanced Thermal Properties.

Polyanhydrides have been studied as a drug delivery vehicles due to their surface-eroding behavior which results in zero-order release. However, many polyanhyrides have thermal and solubility properties that make them difficult to formulate for these applications. Poly[α,α′-bis(ortho-carboxyphenoxy)-para-xylene] (oCPX) is an aromatic polyanhydride that has thermal and solubility properties enabling facile processing. The polymer's in vitro degradation profile exhibited an induction period up to 10 days in which degradation product concentration in the media was minimal, followed by a period of stable release of the biocompatible degradation product. Scanning electron microscope images and molecular weight changes of the polymer matrices confirm that this polymer is primarily surface-eroding. The combination of thermal properties, solubility, polymer degradation time, and erosion mechanism indicate that poly(oCPX) is be a suitable matrix candidate for extended, controlled drug delivery.
Respiratory phases during early sea urchin development, measured with the automatic diver balance

Abstract On the basis of the automatic electromagnetic diver balance a recording microrespirometer has been developed. Using this apparatus the oxygen uptake of unfertilized eggs and developing embryos has been determined. In the former case the respiration remained constant at a value of about 0.20 mμl/h and egg. In conformance with previous observations it was found that the oxygen uptake increases gradually during the early stages, followed by a period of relative constancy during gastrulation. Subsequently a further increase began. The respiration at the constant level was found to lie in the range 1.0–1.5 mμl/embryo and hour. The change in respiratory rate does not follow a smooth curve, rather a number of oscillations are recorded. Variations of this kind have also been observed before, and were suggested to be correlated with the mitotic activity. For a number of reasons the present results do not lend themselves to this interpretation. It is therefore proposed that various epigenetic events other than cell division may occur in separate phases, and that the variations in oxygen uptake may represent bursts of energy consumption associated with such activities. At the moment it is impossible to correlate the respiratory variations with specific embryogenetic events.
Reconstitution of a Core Chromatin Remodeling Complex from SWI/SNF Subunits

Abstract Protein complexes of the SWI/SNF family remodel nucleosome structure in an ATP-dependent manner. Each complex contains between 8 and 15 subunits, several of which are highly conserved between yeast, Drosophila , and humans. We have reconstituted an ATP-dependent chromatin remodeling complex using a subset of conserved subunits. Unexpectedly, both BRG1 and hBRM, the ATPase subunits of human SWI/SNF complexes, are capable of remodeling mononucleosomes and nucleosomal arrays as purified proteins. The addition of INI1, BAF155, and BAF170 to BRG1 increases remodeling activity to a level comparable to that of the whole hSWI/SNF complex. These data define the functional core of the hSWI/SNF complex.
Limit on the detectability of the energy scale of inflation.

We show that the polarization of the cosmic microwave background can be used to detect gravity waves from inflation if the energy scale of inflation is above 2 X 10 1 5 GeV. These gravity waves generate polarization patterns with a curl, whereas (to first order in perturbation theory) density perturbations do not. The limiting "noise" arises from the second-order generation of curl from density perturbations, or rather residuals from its subtraction. We calculate optimal sky coverage and detectability limits as a function of detector sensitivity and observing time.
The Empty Lattice Test of the Cellular Method in Solids

The cellular method of constructing wave functions for electrons in crystals developed principally by Wigner and Seitz and Slater is tested by applying it to an artificial crystal in which the potential is constant. Knowledge of the exact solutions for this case, plane waves, shows that the cellular method is quite accurate in the first Brillouin zone but may be in error by a factor of two in the second. Hence calculations of occupied levels in Li and Na are probably quite good; for Cu, Ca, diamond, LiF, and NaCl the errors will be larger. Calculations of excited states are likely to be very much in error. The accuracy of the cellular method is shown to improve very slowly with increasing number of continuity conditions.
Ultrafast Intersystem Crossing and Spin Dynamics of Photoexcited Perylene-3,4:9,10-bis(dicarboximide) Covalently Linked to a Nitroxide Radical at Fixed Distances

Time-resolved transient optical absorption and EPR (TREPR) spectroscopies are used to probe the interaction of the lowest excited singlet state of perylene-3,4:9,10-bis(dicarboximide) (1*PDI) with a stable tert-butylphenylnitroxide radical (2BPNO•) at specific distances and orientations. The 2BPNO• radical is connected to the PDI with the nitroxide and imide nitrogen atoms either para (1) or meta (3) to one another, as well as through a second intervening p-phenylene spacer (2). Transient absorption experiments on 1−3 reveal that 1*PDI undergoes ultrafast enhanced intersystem crossing and internal conversion with τ ≅ 2 ps to give structurally dependent 8−31% yields of 3*PDI. Energy- and electron-transfer quenching of 1*PDI by 2BPNO• are excluded on energetic and spectroscopic grounds. TREPR experiments at high magnetic fields (3.4 T, 94 GHz) show that the photogenerated three-spin system consists of the strongly coupled unpaired electrons confined to 3*PDI, which are each weakly coupled to the unpaired el...
Interstitial Ectopic Pregnancy—Management with Laparoscopically‐guided Local Methotrexate Infiltration

EDITORIAL COMMENT: This issue of the journal contains 2 case reports of interstitial ectopic pregnancies, both treated by injection of methotrexate, by intramuscular injection in one case, and by laparoscopically-guided injection into the ectopic pregnancy mass in the other. The methods were not equally successful. Parker and colleagues reviewed the published data and concluded that single-dose intramuscular methotrexate for treatment of ectopic pregnancy is associated with a high failure rate, and serious complications have occurred (11). The authors of this report advocate the use of laparoscopically-guided local methotrexate infiltration. The selection of which cases of ectopic pregnancy warrant this regimen is not yet established in the editor's opinion. Ironically one of the reviewers of this case report, selected because of his known experience with ultrasonographically-guided direct local methotrexate injection into early tubal ectopic pregnancies, stated that, because of the risk of causing haemorrhage, that he had preferred methotrexate by intramuscular injection in 2 women with interstitial ectopic pregnancies, who then, at a later date, had excision of the ectopic pregnancies performed laparoscopically. Summary: This case describes the use of ultrasound to diagnose an interstitial ectopic pregnancy and the subsequent management and ultrasound follow-up. Interstitial pregnancy is a rare but potentially life-threatening complication of pregnancy. Management options depend upon the timing of diagnosis, and the desire for maintenance of fertility. Methotrexate injection, under ultrasonographic or laparoscopic guidance, seems to be the management of choice when the ectopic is diagnosed at an early stage.