cssi/SciSciGPT-SciSciNet huggingface dataset:
Crystal structures of a polypeptide processing and secretion transporter

Bacteria secrete peptides and proteins to communicate, to poison competitors, and to manipulate host cells. Among the various protein-translocation machineries, the peptidase-containing ATP-binding cassette transporters (PCATs) are appealingly simple. Each PCAT contains two peptidase domains that cleave the secretion signal from the substrate, two transmembrane domains that form a translocation pathway, and two nucleotide-binding domains that hydrolyse ATP. In Gram-positive bacteria, PCATs function both as maturation proteases and exporters for quorum-sensing or antimicrobial polypeptides. In Gram-negative bacteria, PCATs interact with two other membrane proteins to form the type 1 secretion system. Here we present crystal structures of PCAT1 from Clostridium thermocellum in two different conformations. These structures, accompanied by biochemical data, show that the translocation pathway is a large α-helical barrel sufficient to accommodate small folded proteins. ATP binding alternates access to the transmembrane pathway and also regulates the protease activity, thereby coupling substrate processing to translocation. Gram-positive bacteria use peptidase-containing ATP-binding cassette transporters (PCATs) to export quorum-sensing and antimicrobial polypeptides; here, the X-ray crystal structures of PCAT1 from Clostridium thermocellum in the absence and presence of ATP are reported. This manuscript presents X-ray crystal structures of a protein-translocating ABC transporter, a peptidase-containing ATP-binding cassette transporter (PCAT) from Clostridium thermocellum, in the presence and absence of ATP. The structures and accompanying biochemical experiments indicate that the translocation pathway in this protein is a large α-helical barrel that traverses nearly the entire lipid bilayer; the cavity of this α-helical barrel is large enough to accommodate a small fully folded protein. PCATs are ubiquitous in prokaryotes. In Gram-positive bacteria they export quorum sensing and antimicrobial polypeptides. In Gram-negative bacteria they interact with other membrane proteins as part of the type I secretion system.
Large-Scale Assessment, Rationality, and Scientific Management

SUMMARY This article examines the ways in which NCLB and the movement towards large-scale assessment systems are based on Weber's concept of formal rationality and tradition of scientific management. Building on these ideas, the authors use Ritzer's McDonaldization thesis to examine some of the core features of large-scale assessment and accountability systems. According to Ritzer, McDonaldized systems and routines are characterized by four central features: (a) a pursuit of efficiency; (b) emphasis on calculability or quantification of outcomes; (c) predictability and uniformity; and (d) control through nonhuman technologies. Strengths and shortcomings of each of these features for schools and educators are discussed. The article concludes with ideas and strategies for school psychologists interested in maximizing the benefits and minimizing the negative outcomes of large-scale assessment and accountability systems.
Prediction of a Go/No-go Decision from Single-Trial Activities of Multiple Neurons in Monkey Superior Colliculus

The purpose of this study was to develop an algorithm capable of transforming neural activity to correctly report behavioral outcome during a cognitive task. We recorded from small groups of 2-5 neurons in the superior colliculus (SC) while monkeys performed a go/no-go task. Depending upon the color of a peripheral stimulus, the monkey was required to either make a saccade to the stimulus (go) or maintain fixation (no-go). In order to replicate the progress of the decision-making process and generate a virtual decision function ( VDF ), we performed a multiple regression analysis, with 1 msec resolution, on neuron activity during individual trials. Post hoc analyses by VDF predicted the monkey's choice with nearly 90% accuracy. These results suggest that monitoring of a limited number of SC neurons has sufficient capacity to predict go/no-go decisions on a trial-by-trial basis, and serves as an ideal candidate for a cognitive brain-machine interface (BMI).
Retrofitting legacy code for security

Research in computer security has historically advocated Design for Security, the principle that security must be proactively integrated into the design of a system While examples exist in the research literature of systems that have been designed for security, there are few examples of such systems deployed in the real world Economic and practical considerations force developers to abandon security and focus instead on functionality and performance, which are more tangible than security As a result, large bodies of legacy code often have inadequate security mechanisms Security mechanisms are added to legacy code on-demand using ad hoc and manual techniques, and the resulting systems are often insecure.
Hermod: an interactive behavioral synthesizer for VLSI

Hermod is an interactive behavioral synthesis program. Using a combined control and data-flow graph (C/DFG) as an intermediate representation. Hermod generates functional block representations from behavioral descriptions. Hermod supports a menu-driven interface, displaying the hardware representation for a particular state partitioning. Encouraging user participation in the synthesis process, the system allows the user to control state partitioning and resource sharing through a graphical interface to explore the maximal design space. In developing Hermod, emphasis was also placed on the system's capability to provide an easy verification of system-generated designs. Written in the object-oriented language C++, Hermod generates a hardware representation in several minutes from a behavioral description of practical size on a VAXstation II. >
A multi-institutional analysis of 429 patients undergoing major hepatectomy for colorectal cancer liver metastases: The impact of concomitant bile duct resection on survival

Background Data are lacking on long-term outcomes of patients undergoing major hepatectomy requiring bile duct resection (BDR) for the treatment of colorectal cancer liver metastases. Methods Patients who underwent major hepatectomy (≥3 segments) for metastatic colorectal cancer from 2000–2010 at three US academic institutions were included. The primary outcome was disease-specific survival (DSS). Results Of 429 patients, nine (2.1%) underwent BDR, which was associated with pre-operative portal vein embolization (25.0% vs. 4.3%; P = 0.049). There were no significant differences in age, ASA class, margin status, number of lesions, tumor size, cirrhosis, perineural invasion, or lymphovascular invasion. BDR was independently associated with increased postoperative major complications (OR: 6.22; 95%CI:1.44–26.97; P = 0.015). There were no differences in length of stay, reoperation, readmission, or 30-day mortality. Patients who underwent BDR had markedly decreased DSS (9.3 vs. 39.9 mo; P = 0.002). When accounting for differences between the two groups, the need for BDR was independently associated with reduced DSS (HR: 3.06; 95%CI:1.12–8.34; P = 0.029). Conclusion Major hepatectomy with concomitant bile duct resection is seldom performed in patients undergoing resection of colorectal cancer liver metastases and is associated with higher major morbidity and reduced disease-specific survival compared to major hepatectomy alone. Stringent selection criteria should be applied when patients may need bile duct resection during hepatectomy for colorectal cancer liver metastases. J. Surg. Oncol. 2015; 112:524–528. © 2015 Wiley Periodicals, Inc.
OPL : A ZINC FINGER PROTEIN THAT REGULATES NEURAL DETERMINATION AND PATTERNING IN XENOPUS

In order to study the mechanism of neural patterning in Xenopus, we used subtractive cloning to isolate genes activated early during this process. One gene isolated was opl, (odd-paired-like) that resembles the Drosophila pair-rule gene odd-paired and encodes a zinc finger protein that is a member of the Zic gene family. At the onset of gastrulation, opl is expressed throughout the presumptive neural plate, indicating that neural determination has begun at this stage while, by neurula, opl expression is restricted to the dorsal neural tube and neural crest. opl encodes a transcriptional activator, with a carboxy terminal regulatory domain, which when removed increases opl activity. opl both sensitizes animal cap ectoderm to the neural inducer noggin and alters the spectrum of genes induced by noggin, allowing activation of the midbrain marker engrailed. Consistent with the later dorsal neural expression of opl, the activated form of opl is able to induce neural crest and dorsal neural tube markers both in animal caps and whole embryos. In ventral ectoderm, opl induces formation of loose cell aggregates that may indicate neural crest precursor cells. Aggregates do not express an epidermal marker, indicating that opl suppresses ventral fates. Together, these data suggest that opl may mediate neural competence and may be involved in activation of midbrain, dorsal neural and neural crest fates.
Hyperfibrinogenemia in Schizophrenia

The mean plasma fibrinogen concentrations in one group each of newly admitted and institutionalized male schizophrenic patients were found to be significantly increased (p < 0.001) above normal. The results could not be attributed to occult medical disease.
Critical Moments as Relational Moments: The Centre for Humanitarian Dialogue and the Conflict in Aceh, Indonesia

Comments about the role of the mediator made by Lakhdar Brahimi, United Nations Special Envoy to Afghanistan, frame this inquiry into the relational milieu favorable to dialogue that explores a series of facilitated discussions between the Free Aceh Movement (GAM) and the Republic of Indonesia convened by the Henry Dunant Centre (HDC). Participants were interviewed as part of an oral history project investigating critical moments in negotiation. This method permitted an in-depth study of a dialogue process as it was understood by the parties themselves, and highlighted the distinctive perspectives practitioners bring to bear with respect to accounting for decisive shifts in negotiation. Critical moments, for this dialogue community, included both macrolevel turning points and microlevel relational exchanges. Attention to the microprocess of exchanges deemed critical by participants suggests the crucial roles played by the practitioners’ attitudes and relational dispositions.
Yeast Lacking Superoxide Dismutase(s) Show Elevated Levels of “Free Iron” as Measured by Whole Cell Electron Paramagnetic Resonance

Abstract A current hypothesis explaining the toxicity of superoxide anion in vivo is that it oxidizes exposed [4Fe-4S] clusters in certain vulnerable enzymes causing release of iron and enzyme inactivation. The resulting increased levels of “free iron” catalyze deleterious oxidative reactions in the cell. In this study, we used low temperature Fe(III) electron paramagnetic resonance (EPR) spectroscopy to monitor iron status in whole cells of the unicellular eukaryote, Saccharomyces cerevisiae. The experimental protocol involved treatment of the cells with desferrioxamine, a cell-permeant, Fe(III)-specific chelator, to promote oxidation of all of the “free iron” to the Fe(III) state wherein it is EPR-detectable. Using this method, a small amount of EPR-detectable iron was detected in the wild-type strain, whereas significantly elevated levels were found in strains lacking CuZn-superoxide dismutase (CuZn-SOD) (sod1Δ), Mn-SOD (sod2Δ), or both SODs, throughout their growth but particularly in stationary phase. The accumulation was suppressed by expression of wild-type human CuZn-SOD (in the sod1Δ mutant), by pmr1, a genetic suppressor of the sodΔ mutant phenotype (in thesod1Δsod2Δ double knockout strain), and by anaerobic growth. In wild-type cells, an increase in the EPR-detectable iron pool could be induced by treatment with paraquat, a redox-cycling drug that generates superoxide. Cells that were not pretreated with desferrioxamine had Fe(III) EPR signals that were equally as strong as those from treated cells, indicating that “free iron” accumulated in the ferric form in our strains in vivo. Our results indicate a relationship between superoxide stress and iron handling and support the above hypothesis for superoxide-related oxidative damage.
CYCLOPROPANE FATTY ACID METABOLISM: PHYSICAL AND CHEMICAL IDENTIFICATION OF PROPANE RING METABOLIC PRODUCTS IN THE ADIPOSE TISSUE.

Twelve male weanling rats were distributed equally into 3 groups and placed on fat-free diets. The diets of groups 1 and 2 were supplemented with 0.54% of recemic methylcis-9,10-methylene octadecanoate (CMO) and racemic methyltrans-9,10-methylene octadecanoate (TMO), respectively. Group 3 served as a control. Gas liquid chromatography (GLC) analyses of the adipose tissue methyl esters indicated at the level fed, that cyclopropane fatty acids do not affect normal fatty acid metabolism as has been shown for cyclopropene fatty acids. GLC analyses of groups 1 and 2 revealed the presence of a different unidentified fatty acid for each of the acids fed in addition to the CMO and TMO acids themselves. Each of the unidentified acids and the CMO and TMO acids were isolated and purified by preparative GLC. The absolute identity of the CMO and TMO acids fed and isolated from body fat was established by IR, NMR, and mass spectra. The biodegradation products of the CMO and TMO esters were shown to becis- andtrans-3,4-methylene dodecanoic acid, respectively. Unequivocal proof of structure was established through synthesis followed by comparison of IR, NMR, and mass spectra and melting points, GLC retention times, and elemental analyses with those obtained for the degradation products. Neither member of the racemic mixtures of either thecis or thetrans cyclopropane acids was preferentially utilized by the rat as shown by the lack of octical activity in the degradation products and the CMO and TMO acids isolated from the body fat. The accumulations of the 3,4-methylene dodecanoic acids in the adipose tissue of the rats fed CMO and TMO cyclopropane fatty acids suggest the inability of the beta oxidation enzyme system to proceed past the cyclopropane ring in a fatty acid chain. The synthesis ofcis- andtrans-3-dodecenoic acids, intermediates in the synthesis of the 3,4-methylene dodecanoic acids, and the geometrical cyclopropane isomers are discussed.
An operating systems project using structured methodology

This paper describes a simple microcomputer project which we found to be successful in teaching operating systems principles. The project involved designing and implementing a very simple operating system kernel. It is appropriate for a one quarter introductory course. Structured techniques were a requirement during the design and coding phases.
Trypanosoma pacifica sp. n. from the English Sole Parophrys vetulus Girard from Oregon

SYNOPSIS Trypanosoma pacifica sp. n. is described from the blood of the English sole, Parophrys vetulus Girard, from Oregon. The total length averages 35.9 μm of which 15.4 μm is free flagellum. Comparisons are made with other trypanosomes reported from related species of fishes and with those reported from marine fishes adjacent to North America.
Effect of oxidation on the physical structure of soot

The physical structure of soot during oxidation in atmospheric pressure flames at 1580 to 1860 K was studied using light scattering and absorption techniques to determine the soot particle size and number concentration as a function of distance from the burner. Complementary measurements of soot particle size were performed using probe sampling, electron microscopy, and electrical mobility analysis, and specific surface area and pore size measurements were performed using nitrogen adsorption techniques. The particle number concentration is found to increase while the particle size and mass concentration decrease during soot oxidation in fuel-lean to slightly fuel-rich flames. Most of the increase in particle number occurs when the soot burnout reaches about 80% completion. In more fuel-rich flames, the number concentration remains constant during burnout. The data are interpreted to mean that soot aggregates or particles break up during oxidation under fuel-lean conditions as a consequence of internal burning by O 2 . The breakup does not occur under the more fuelrich conditions where essentially the only oxidizing species is OH, which is far more reactive than O 2 and gives much less internal burning. This interpretation is consistent with predicted extents of penetraltion of O 2 and OH into intra-aggregate spaces and into pores within the building units of the aggregates. The depolarization ratio of the soot was found to be 0.013 initially, consistent with previous studies, and 0.002 in the later stages of burnout. This low value is consistent with the observation of particles with low aspect ratio in later stages of burnout and the view that shape anisotropy is the controlling depolarization parameter.
Cultural transmission of learned behavior among male bobwhite quail (Colinus virginianus)

Cultural transmission of utilization of a learned food source was demonstrated across five sequential cultural generations of male bobwhite quail. Inclusion of control procedures that allow estimation of the probable spontaneous occurrence of the behavior, which unfortunately are not included in many studies of cultural transmission phenomena, indicated that, although behavioral acquisition also occurred among female bobwhite quail, the acquisition could not be attributed to cultural transmission among the females.
Decreased mesenteric vascular response to angiotensin II in portal hypertension

We studied the mesenteric and systemic vascular response to angiotensin II in normotensive and portal hypertensive (PHT) rabbits, because of the documented poor tolerance of hemorrhagic shock in PHT. Normally, the hemodynamic response to angiotensin II (AII) is characterized by selective and disproportionate splanchnic vasoconstriction. We postulated that the response to AII could be diminished in PHT. Chronic PHT was induced by partial portal vein ligation 3 weeks prior to graded angiotensin II infusion. Baseline hemodynamic measurements showed markedly elevated portal pressure (PPv) and superior mesenteric artery blood flow (QSMA) compared with those of normotensive animals (P < 0.01). Superior mesenteric artery resistance (RSMA) was markedly reduced in PHT compared to that in controls (P < 0.05). Angiotensin II infusion in normals resulted in a marked selective rise in Rsn1A compared with the rise in systemic resistance (RsYs) (P < 0.01). All infusion in PHT resulted in a rise in RSMA and RsYs, but the disproportionate in RSMA was attenuated. Furthermore, in both normal and PHT, AII caused a significant rise in PPV(P < 0.01). We conclude that the findings indicate that the splanchnic vasoconstrictive response to AII is substantially impaired in PHT, and that AII will paradoxically cause a rise in PPV, possibly aggravating the tendency to hemorrhage in PHT.
Exchange of catenins in cadherin–catenin complex

beta-Catenin is an intracellular multifunctional protein. In complex with the transmembrane adhesive receptor E-cadherin, it becomes plasma membrane-associated and mediates intercellular adhesion. A cytosolic pool of beta-catenin interacts with DNA-binding proteins and participates in signal transduction. To reveal the possible cross-talk between these two pools, we studied whether beta-catenin is exchanged between its free and cadherin-bound states. We found that pulse-labeled beta-catenin replaces the beta-catenin bound to the cell surface prebiotinylated E-cadherin immediately after synthesis. Approximately 25% of all pulse-labeled beta-catenin destined for E-cadherin associates with this protein via this mechanism. The rest of the newly synthesized beta-catenin arrives at the plasma membrane in a complex with the E-cadherin precursor. Immediately after arrival, this beta-catenin pool is transferred to the prebiotinylated E-cadherin. beta-Catenin released from E-cadherin may participate in new exchange cycles. This beta-catenin exchange is strongly affected in cells that contain mutations in the tumor suppressor gene APC. This process may contribute significantly to both cell-cell adhesion and beta-catenin-dependent signaling.
Kinetic studies of NHx radical reactions

Abstract Combined experimental and theoretical studies of the reactions and were carried out in the present work. The rate constant of reaction (1) was investigated in the temperature range 293 K ⩽ T ⩽612 K using the laser photolysis continuous-wave laser-induced fluorescence technique for the production and detection of NH 2 . The results are well described by k 1 ( T )=5.43× T −4.02 exp(−1034 K/T ) cm 3 molecule −1 s −1 . Stationary points on the potential energy surface were characterized using the gaussian -2 (G2) ab initio method. The surface is complex, with hydrogen-atom transfers and cis—trans isomerization connecting five stable adduct species. The product distribution of reaction (2) was studied at room temperature using the discharge flow technique with mass spectrometric detection of the reaction products. Measured branching fractions for the production of N 2 O+H(D) were k 2a / k 2 = 0.84±0.4 for NH+NO and k 2a / k 2 = 0.87±0.17 for ND+NO. Stationary points on the ground 2 A′ surface were calculated using the G2 method. The transition state energy for the dissociation of the cis isomer into H+N 2 O was found to be lower than the transition state energy for dissociation into OH+N 2 . Additionally, trans -HNNO was found to isomerize to cis -HNNO before dissociation. For reaction (3), the molecular properties of all relevant intermediates and transition states on the ground state potential energy surface were determined using the G2 method. The results predict the formation of three intermediates, H 2 NO, trans -HNOH and cis -HNOH, all exothermic relative to the reactants. The transition states separating these intermediates from one another and their products (H 2 +NO, H+HNO( 1 A′) or NH+OH) were also characterized, several for the first time.
Path of bulk water movement through the urinary bladder of the toad.

Vasopressin increases bulk water flow across the toad bladder. To resolve whether this flow proceeds primarily between or through the surface epithelial cells, the maximum intercellular flow rate was calculated. Since the experimental flow rate is 28 times the calculated maximum, bulk water flow is likely to proceed largely through the cells of the mucosal epithelium.
Congenital heart disease in the Pierre Robin syndrome

Congenital heart disease occurs in about 20 percent of patients with Pierre Robin syndrome. Ventricular septal defect, patent ductus arteriosus, and atrial septal defect are the most common congenital cardiac lesions in this syndrome. The associated upper airway obstruction can produce cor pulmonale, cardiomegaly, pulmonary edema, and cyanosis.
Preparation of oriented Bi‐Ca‐Sr‐Cu‐O thin films using pulsed laser deposition

Oriented c‐axis thin films of Bi‐Ca‐Sr‐Cu‐O on [100] SrTiO3 substrates have been fabricated using the pulsed excimer laser evaporation technique. Deposition at room temperature in 1 mTorr oxygen followed by an 875 °C anneal in oxygen yields superconducting films with zero resistance at 80 K and a resistivity drop near 110 K, hinting at the presence of another superconducting phase. Transmission electron microscopy shows that the films are epitaxial with the substrate, with an abrupt and planar interface boundary. The observed crystal structure is consistent with diffraction results on bulk materials.
Activity and affect in early memories of adolescent boys.

Summary The reporting of early memories is seen as a valuable projective technique, particularly because it is relatively “culture-free.” Sets of early memories individually reported by 32 adolescent boys were coded on the dimensions of activity vs. passivity and positive vs. negative affect. Variation in these early memory dimensions, hypothesized to be associated with variation in measures of current self-representation and coping effectiveness, was found to be significantly related to active stance in figure drawings, self-description as an initiator, and Witkin's measures of differentiation of body-concept and sense of separate identity. These findings provide support for the validity of early memories as a projective technique.
The relation between intracellular pH and rate of protein synthesis in sea urchin eggs and the existence of a pH-independent event triggered by ammonia

Abstract The relation between rate of protein synthesis and intracellular pH (pH i ) was investigated in the eggs of the sea urchin Strongylocentrotus purpuratus . Increasing external pH (pH o ) resulted in raising pH i of eggs and also in increased rate of protein synthesis. Similarly, at constant pH o , adding various concentrations of NH 4 Cl to eggs caused graded increases of both pH i and protein synthesis. Using various concentrations of NH 4 Cl at a low pH o and incubating eggs at high pH o , we compared protein synthesis under similar pH i conditions and this revealed that at least half the increased protein synthesis stimulated by NH 4 Cl is independent of induced rise of pH i , as also seems to be chromosome condensation which was never observed in eggs incubated at high pH o s. The additional pH-independent event triggered by NH 4 Cl does not appear related to elevated free Ca 2+ , since protein synthesis and chromosome condensation do not require external Ca 2+ and no increases of free Ca 2+ sufficient to activate the Ca 2+ -calmodulin-mediated enzyme NAD kinase occurred. Monensin disrupts intravesicular pH gradients but does not stimulate protein synthesis, indicating that this local effect, also promoted by NH 4 Cl, is not involved in ammonia-induced increase of protein synthesis. Using two other amines which have low pK a values, benzocaine and tricaine, we observed 2-fold increases in protein synthesis rates, even though pH i was lowered. While the exact nature of the pH-independent event(s) triggered by NH 4 Cl, and possibly by other amines, remains unidentified, its possible involvement in normal mitosis is stressed.
Design of a high-efficiency minimum-torque-ripple 12-V/1-kW three-phase BLDC motor drive system for diesel engine emission reductions

A 12-V motor drive system using an onboard battery is promising in vehicle applications, e.g., to rotate an air pump to adjust its air delivery to the burner, thereby providing autonomous exhaust temperature control for the conventional diesel engine vehicle. The 12-V/1-kW motor drive system proposed in this paper consists of a series-resonant LLC MOSFET full-bridge converter, which provides high-efficiency power transfer by implementing zero voltage switching and boosts the dc bus to ~300 V, and an insulated-gate bipolar transistor inverter, which provides the high-side phase currents to a 1-kW/6000-r/min brushless dc motor (BLDC). This design secures the high efficiency, low cost, and low volume. Meanwhile, with the variable output voltage of this dc/dc converter, this paper realizes a commutation torque-ripple reduction method, which will minimize the mechanical vibration. Experimental results on this prototype system demonstrate that: 1) the LLC dc/dc part efficiency is 97.6% with 92% of the inverter efficiency; and 2) the motor commutation torque ripple is reduced close to zero.
OUTCOMES OF INOPERABLE PATIENTS UNDERGOING TRANSAPICAL AND TRANSAORTIC TRANSCATHETER AORTIC VALVE REPLACEMENT: A PARTNER 2B SUBSTUDY ANALYSIS OF NESTED REGISTRIES

Transcatheter aortic valve replacement (TAVR) has emerged as the treatment of choice for many inoperable and high risk patients with aortic stenosis. In patients without appropriate transfemoral (TF) access, transapical (TA) TAVR has been shown to be an appropriate alternative to surgery. Little is
Stoichiometric and electrostatic characterization of calcium binding to native and lipid-substituted adenosinetriphosphatase of sarcoplasmic reticulum.

Abstract The stoichiometry of calcium binding to specific sites (i.e., those producing enzyme activation) was found to be 8–10 nmol/mg protein in native sarcoplasmic reticulum vesicles, and 13.9–15.4 nmol/mg of ATPase purified by non-ionic detergent solubilization and anion exchange chromatography. Parallel measurements of phosphoenzyme yielded levels of 4.0–4.9 and 6.0–7.7 nmol/mg of protein in the two preparations, respectively, demonstrating that each 115 kDa ATPase chain includes one catalytic site and two calcium binding sites. The apparent association constant, K = (6 ± 2)·10 5 M −1 , and the binding cooperativity, n H = 1.9 , were unchanged when measurements were carried out with native sarcoplasmic reticulum vesicles and when the membrane surface charge was altered by lipid substitution with phosphatidylcholine or phosphatidylserine, at neutral pH in the presence of 10 mM MgCl2 and 80 mM KCl. On the other hand, the apparent association constant was increased in the absence of Mg2+ or, to a lesser extent, in the absence of monovalent cations. It was also observed that the cooperative character of the calcium binding isotherms was reduced in low ionic-strength media. Analysis of the electrostatic effects indicates that the calcium-binding domain is shielded from the membrane phospholipid surface charge by virtue of its location within the ATPase protein. The effects of various electrolytes are attributed to monovalent-cation binding in the calcium-binding domain. The apparent loss of cooperativity of the calcium binding isotherms at low ionic strength is attributed to a progressive displacement of the titration curve which is minimal at low degrees of saturation and becomes larger at higher degrees of saturation. This behavior is described quantitatively by the progressive effect of calcium binding on an electrostatic potential generated by localized protein charge densities within, or near, the calcium-binding domain.
Separation of ternary salt/acid aqueous solutions using hollow fiber reverse osmosis

Abstract A hollow fiber reverse osmosis system was used to separate ternary mixtures of sodium chloride and acetic acid aqueous solutions to investigate interactions between an inorganic salt and a weak organic acid which does not ionize extensively. Acetic acid rejection is enhanced and permeability is decreased by adding NaCl to the solution. Conversely, the separation of NaCl is decreased and permeability increased as the concentration of acetic acid in the mixture is increased. Furthermore, the permeability of acetic acid in the polyamide hollow fiber membrane is approximately one order of magnitude larger than that of the salt. The results suggest that it may be possible to purify etching solutions of weak acids by passing water and unionized acid through the membrane and rejecting ionized and particulate constituents. The linear relationship between the inverse of salt rejection and the inverse of solvent flux, as developed by Pusch (1977) for flat membranes and later applied by Soltanieh and Gill (1981, 1982, 1984) to hollow fiber systems on the basis of the completely-mixed model, also is valid in this case which involves ternary solutions. The coupling between the components of mixtures shown in this study may be useful in understanding better applications as diverse as treatment by the reverse osmosis of etching solutions of microelectronic industries to wastewaters from oil shale retorting, metal finishing industries and other wastes streams involving organic/inorganic mixtures.
Cause of Increased Fraǵility of Erythrocytes in Congestive Heart Failure

ConclusionsIncrease in fragility of the red blood cells to hypotonic saline occurs in capillary blood in the presence of circulatory arrest. This is similar in degree and direction to that observed in congestive heart failure. These alterations may also be observed in certain samples obtained from a vein which contains an appreciable amount of capillarv blood.
Interaction of adrenergic stimuli, prostaglandins and angiotensin II in the dog kidney.

SummaryIn the anesthetized dog, neither renal angiotensin II blockade nor systemic administration of meclofenemate altered the renal vascular response to renal nerve stimulation or exogenous norepinephrine. Systemic administration of indomethacin enhanced the renal vascular response to exogenous norepinephrine but not to renal nerve stimulation. Renal blockade to angiotensin II, alone or combined with renal α-adrenergic receptor blockade produced by phenoxy-benzamine did not affect the renal vasoconstrictor response to systemically administered indomethacin or meclofenemate. These data demonstrate that neither endogenous circulating angiotensin II nor prostaglandins significantly alter the effects of the sympathetic nervous system on the canine renal vascular bed. The renal vasoconstriction associated with systemic indomethacin or meclofene-mate administration is not due to unopposed angiotensin II or α-adrenergic agonist vasoconstrictor action but rather to the withdrawal of endogenous prostaglandin vaso...
Small-scale changes of core-mantle boundary reflectivity studied using core reflected PcP

Abstract Short-period PcP phases from earthquakes in the western Aleutians recorded at the Canadian Yellowknife array (YKA) sample the core-mantle boundary (CMB) beneath the Alaskan Kenai peninsula and the Cook inlet. The PcP -to- P amplitude ratios for these events show large variability with some amplitude ratios more than an order of magnitude larger than predicted by radial Earth models such as IASP91 or PREM. The amplitude ratios vary laterally with PcP core-mantle boundary reflection points showing a ∼1° region with exceptionally large amplitude ratios. It is likely that the variability in relative PcP amplitudes is due in large part to CMB topography. Other mechanisms, such as radiation pattern; mantle attenuation; focusing and defocusing; and core-mantle boundary velocity and density perturbations could cause variations on scale-lengths of less than a degree as found in this study, but are unable to produce variations as large as those we observe.
Protective effects of rheumatoid arthritis in septic ICU patients

We used the Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC II) database to analyze factors contributing to the mortality of intensive care unit (ICU) patients with severe sepsis. We found that septic patients with rheumatoid arthritis (RA) have significantly lower observed mortality rates than patients without the condition. Further, differences in gender, age, disease severity, and patients' use of corticosteroids did not explain this phenomenon, suggesting that the observed protective effect is specific to RA.
A coaching intervention for college students with Attention Deficit/Hyperactivity Disorder

In this article we describe coaching as an intervention for college students with attention deficit/hyperactivity disorder (ADHD). Coaching college students with ADHD empowers individuals to organize and execute their responsibilities, both in academia and in everyday life. With the assistance of a coach, individuals with ADHD can create structure and execute change by identifying strategies that circumvent their deficits in executive functioning. We also present an example of a representative client to illustrate the methods used in coaching. Given the increased risks facing college students with ADHD, coaching is a useful complement to academic advising and intensive therapy. Our discussion includes obstacles to implementing and evaluating an ADHD coaching intervention. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 647–656, 2005.
Examination of nonequilibrium effects in an ionized nitrogen flow

A thermo-chemical nonequilibrium ionized nitrogen flow in a shock tube is examined. A one-dimensional computational fluid dynamics code has been developed to study the flowfield incorporating a novel treatment of the electron energy equation. In the present approach, the electron pressure is included in the electron energy flux. In contrast, previous work has removed this term from the flux to facilitate the flux splitting. The code uses a five-species gas model for ionized nitrogen characterized by translational-rotational, vibrational, and electron-electronic temperatures. The results give good agreement with experimental data except for an inadequacy in the electronic source terms. A small difference is observed between the new and old splittings which increases with higher levels of ionization.
Calculation of vibrational shifts of nitrile probes in the active site of ketosteroid isomerase upon ligand binding.

The vibrational Stark effect provides insight into the roles of hydrogen bonding, electrostatics, and conformational motions in enzyme catalysis. In a recent application of this approach to the enzyme ketosteroid isomerase (KSI), thiocyanate probes were introduced in site-specific positions throughout the active site. This paper implements a quantum mechanical/molecular mechanical (QM/MM) approach for calculating the vibrational shifts of nitrile (CN) probes in proteins. This methodology is shown to reproduce the experimentally measured vibrational shifts upon binding of the intermediate analogue equilinen to KSI for two different nitrile probe positions. Analysis of the molecular dynamics simulations provides atomistic insight into the roles that key residues play in determining the electrostatic environment and hydrogen-bonding interactions experienced by the nitrile probe. For the M116C-CN probe, equilinen binding reorients an active-site water molecule that is directly hydrogen-bonded to the nitrile p...
Polyubiquitination by HECT E3s and the Determinants of Chain Type Specificity

Polyubiquitination can mediate several different biochemical functions, determined in part by which lysine of ubiquitin is used to link the polyubiquitin chain. Among the HECT domain ubiquitin ligases, some, such as human E6AP, preferentially catalyze the formation of K48-linked polyubiquitin chains, while others, including Saccharomyces cerevisiae Rsp5 and human Itch, preferentially catalyze the formation of K63-linked chains. The features of HECT E3s that determine their chain type specificities have not been identified. We show here that chain type specificity is a function solely of the Rsp5 HECT domain, that the identity of the cooperating E2 protein does not influence the chain type specificity, that single chains produced by Rsp5 contain between 12 and 30 ubiquitin moieties, and that the determinants of chain type specificity are located within the last 60 amino acids of the C lobe of the HECT domain. Our results are also consistent with a simple sequential-addition mechanism for polyubiquitination by Rsp5, rather than a mechanism involving the formation of either E2- or E3-linked polyubiquitin chain transfers.
The derivation of performance expressions for communication protocols from timed petri net models

Petri Net models have been extended in a variety of ways and have been used to prove the correctness and evaluate the performance of communication protocols. Several extensions have been proposed to model time. This work uses a form of Timed Petri Nets and presents a technique for symbolically deriving expressions, which describe system performance. Unlike past work on performance evaluation of Petri Nets which assumes a priori knowledge of specific time delays, the technique presented here applies to a wide range of time delays so long as the delays satisfy a set of timing constraints. The technique is demonstrated using a simple communication protocol.
A novel use of a telescope to photograph metal diaphragm openings.

Image converter camera and astronomical telescope arrangement for photographing metal diaphragm openings in shock tube
Differing vigilance among gray squirrels (Sciuridae carolinensis) along an urban-rural gradient on Long Island.

Urbanization has had far-reaching effects on the wildlife that have adapted to this novel landscape. Not only have wildlife endured shifts in ecosystem function as a result of urbanization, but in many areas there has been a fundamental behavioral change. This “urban wildlife syndrome” – the collection of observable traits of wildlife species undergoing urbanization – prompted us to examine the effect of urbanization on vigilance of eastern gray squirrels (Sciurus carolinensis). We hypothesized that squirrels in more urban locations, due to presumed higher squirrel density and familiarization with humans, would be less vigilant than squirrels in more rural sites. We assigned study sites (i.e. city parks) to one of four rank categories of urbanization based upon human population density. In contrast to our original hypothesis, squirrels in urban sites were more vigilant than squirrels in less urban areas. In fact this difference was punctuated by an approximate 42 % reduction between moderately urban and semi-rural habitats. Squirrel density had a positive, yet weak, effect on vigilance time. Elevated intraspecific aggression, unpredictable changes in vehicular and pedestrian traffic, and associated noise levels and disturbance in urban settings where squirrels occur, may be responsible for more variable and heightened states of vigilance in the urban setting.
EFFECT OF INCREASED INTRAABDOMINAL PRESSURE ON PENTANYL ELIMINATION IN NEONATAL LAMBS

Increased intraabdominal pressure (IAP) might occur during closure of abdominal wall defects. IAP has been shown to reduce clearance of fentanyl. MASEY et al. found acutely decreased portal flow with IAP. As it is important to also measure dactus venosus (DV) shunt and not hepatic blood flow to calculate clearance of fentanyl, we studied 6 neonatal lambs aged 4-48 hours. Fentanyl concentration was kept at 20 ng/ml. Organ blood flows were determined by a standard method, using radiolabelled microspheres. IAP was produced by a blood pressure cuff around the abdomen. Conclusion: Our study confirms that in neonatal lambs with IAP hepatic fentanyl clearance goes down. In addition we showed that DV shunt also decreases significantly, whereas no significant changes were found in portal or hepatic blood flow with IAP.
Acquired renal cystic disease in children prior to the start of dialysis

This report describes the clinical course and serial sonographic findings in three children who developed acquired renal cystic disease (ARCD) prior to the institution of dialysis. The children were aged from 3 years to 13 years and their estimated glomerular filtration rate varied from 8 to 13 ml/min per 1.73 m2 when ARCD was diagnosed. Their primary renal disorders, which included hemolytic-uremic syndrome and focal segmental glomerulosclerosis, had been present for 1.5–11.5 years prior to the cysts being discovered. These patients show that ARCD may develop in children with chronic progressive renal parenchymal disease prior to the institution of specific therapy for end-stage renal disease.
Voluntary Disclosure, Information Asymmetry, and Insider Selling through Secondary Equity Offerings*

This paper examines the relation of voluntary disclosure of management earnings forecasts and information asymmetry to insider selling through secondary equity offerings. We hypothesize that the pattern of voluntary disclosure and level of information asymmetry prior to secondary equity offerings differs systematically based on the identity of the seller. Specifically, we predict a greater frequency of voluntary disclosure and decreased level of information asymmetry when managers sell their stock through a secondary offering. We examine this hypothesis in a cross-sectional analysis of 210 secondary equity offerings from 1984-91, using a two-stage conditional maximum likelihood simultaneous equations estimation procedure, which allows for possible endogeneity in the manager's decision to sell stock. Consistent with our predictions, we document a significantly positive association between managerial participation and voluntary disclosure of earnings forecasts in the nine-month period prior to registration of the offering. We also document a significantly negative association between managerial participation and two proxies for information asymmetry. The findings provide evidence that managers act as if reduced information asymmetry correlates with a reduced cost of capital.
FUNDAMENTAL CONSIDERATIONS FOR THE DESIGN OF NON-LINEAR VISCOUS DAMPERS

An Erratum has been published for this article in Earthquake Engineering and Structural Dynamics 2000; 29(7):1076. Two interrelated issues related to the design of non-linear viscous dampers are considered in this paper: structural velocities and equivalent viscous damping. As the effectiveness of non-linear viscous dampers is highly dependent on operating velocities, it is important to have reliable estimates of the true velocity in the device. This should be based on the actual relative structural velocity and not the commonly misused spectral pseudo-velocity. This is because if spectral pseudo-velocities (PSV) are used, they are based on design displacements (Sv=ω0Sd) and are thus fundamentally different from the actual relative structural velocity. This paper examines the difference between these two velocities, and based on an extensive study of historical earthquake motions proposes empirical relations that permit the designer to transform the well-known spectral pseudo-velocity to an actual relative structural velocity for use in design. Non-linear static analysis procedures recommended in current guidelines for the design of structural systems with supplement damping devices are based on converting rate-dependent device properties into equivalent viscous damping properties based on an equivalent energy consumption approach. Owing to the non-linear velocity dependence of supplemental devices, an alternative approach for converting energy dissipation into equivalent viscous damping is advanced in this paper that is based upon power consumption considerations. The concept of a normalized damper capacity (ϵ) is then introduced and a simple design procedure which incorporates power equivalent linear damping based on actual structural velocities is presented. Copyright © 1999 John Wiley & Sons, Ltd.
Post-FTO Performance Evaluations of Rookie Police Officers

Abstract The literature surrounding the Field Training Officer (FTO) program examines how police recruits navigate post-academy on-the-job training, the reactions these novices have, and how these fledgling officers assess their training experience. Absent from this literature is any consideration of how new officers perform after graduation from the FTO program. The present study examines 347 monthly evaluations issued by immediate supervisors for 66 rookies at the Tallahassee (FL) Police Department. An analysis of scores registered in 18 areas over the first six months after FTO completion determines that race and sex of the sergeant and officer exhibit a statistical influence on grading practices. While these effects do not appear to taint the transition from probationary to full employment status, long-term ramifications are explored.
Maternal‐Infant Health Care: A Comparison Between the United States and West Germany

The health and well-being of mothers and infants are of world-wide concern. Although the United States spends more money on health care than most other countries, it continues to lag behind other countries in its infant mortality rate (IMR). The author's perusal of research reports and her work experience in a hospital maternity setting in both the United States and West Germany (before the recent unification) suggest that the United States could benefit by reviewing the experience of others. The author also describes several strategies used in Germany to reduce its IMR--practices that could be implemented in the United States.