cssi/SciSciGPT-SciSciNet huggingface dataset:
Adenosine Metabolism in Toxoplasma gondii: Potential Targets for Chemotherapy

Toxoplasma gondii is an intracellular parasitic protozoan that infects approximately a billion people worldwide. Infection with T. gondii represents a major health problem for immunocompromised individuals, such as AIDS patients, organ transplant recipients, and the unborn children of infected mothers. Currently available drugs usually do not eradicate infection and as many as 50% of the patients do not respond to this therapy. Furthermore, they are ineffective against T. gondii tissue cysts. In addition, prolonged exposure to these drugs induces serious host toxicity forcing the discontinuation of the therapy. Finally, there is no effective vaccine currently available for the treatment of toxoplasmosis. Therefore, it is necessary to develop new and effective drugs for the treatment and management of toxoplasmosis. The rational design of a drug depends on the exploitation of fundamental biochemical or physiological differences between pathogens and their host. Some of the most striking differences between T. gondii and their mammalian host are found in purine metabolism. T. gondii, like most parasites studied, lack the ability to synthesize purines do novo and depend on the salvage of purines from their host to satisfy their requirements of purines. In this respect, the salvage of adenosine is the major source of purines in T. gondii. Therefore, interference with adenosine uptake and metabolism in T. gondii can be selectively detrimental to the parasite. The host cells, on the other hand, can still obtain their purine requirements by their de novo pathways. This review will focus on the broad aspects of the adenosine transport and the enzyme adenosine kinase (EC 2.7.1.20) which are the two primary routes for adenosine utilization in T. gondii, in an attempt to illustrate their potentials as targets for chemotherapy against this parasite.
Structural determinants for naturally evolving H5N1 hemagglutinin to switch its receptor specificity.

Summary Of the factors governing human-to-human transmission of the highly pathogenic avian-adapted H5N1 virus, the most critical is the acquisition of mutations on the viral hemagglutinin (HA) to "quantitatively switch" its binding from avian to human glycan receptors. Here, we describe a structural framework that outlines a necessary set of H5 HA receptor-binding site (RBS) features required for the H5 HA to quantitatively switch its preference to human receptors. We show here that the same RBS HA mutations that lead to aerosol transmission of A/Vietnam/1203/04 and A/Indonesia/5/05 viruses, when introduced in currently circulating H5N1, do not lead to a quantitative switch in receptor preference. We demonstrate that HAs from circulating clades require as few as a single base pair mutation to quantitatively switch their binding to human receptors. The mutations identified by this study can be used to monitor the emergence of strains having human-to-human transmission potential.
The effects of communication motives, interaction involvement, and loneliness on satisfaction: A model of small groups.

A small group model was tested that traced the path by which communication motives influenced interaction involvement and loneliness and the ways that these factors, in turn, influenced group satisfaction. Results indicated that pleasure was a reason for communicating responsively, whereas escape, control, and inclusion were not reasons. Escape was not a motive reported by those who were lonely. With regard to group satisfaction, it was found that loneliness was a mediatingfactor in that members who interacted responsively were not lonely, and those who were not lonely reported satisfaction with the group. Finally, there was a direct link between the need for affection and satisfaction. Implications of the model's findings support the need for communication skills training and understanding members' motives for interacting in ongoing task groups.
Intelligent processing for metal atomization

Abstract Clean metal powders are produced primarily by gas atomization. Currently, process control depends on operator experience and involves trial and error to reach an acceptable steady state process window. Application of the Intelligent Processing of Materials (IPM) concept to the metal atomization process was investigated by developing an atomizer simulator and a rule-based expert system (ES). The latter diagnoses process problems and recommends corrective changes to process parameters. It uses mechanistic models, empirical correlations, and expert knowledge. Corrective changes are suggested in order of priority and transmitted to an operator for action. Diagnosis and corrections are repeated if necessary. The ES has been exercised under various combinations of initial process parameters, and thus far has consistently guided (simulated) atomizer operation to a steady state process window. Although the present ES and simulator are simple, they illustrate the IPM concept and provide a basis for further implementation of this approach to metal atomization. In future, the expert system can be extended to include quantitative corrections and act as an advisor to the control system.
A 2.5-mm outer diameter photoacoustic endoscopic mini-probe based on a highly sensitive PMN-PT ultrasonic transducer

We have developed a 2.5-mm outer diameter photoacoustic endoscopic mini-probe to use in the instrument channel (typically 2.8 or 3.7 mm in diameter) of standard video endoscopes. To achieve adequate signal sensitivity, we fabricated a focused ultrasonic transducer using a highly-sensitive PMN-PT piezoelectric material. We quantified the PMN-PT transducer's operating parameters and validated the mini-probe's endoscopic imaging capability through an ex vivo imaging experiment on a rat colon.
Analysis of central nervous system involvement in the microwave auditory effect

Abstract Nine cats were prepared for the recording of potentials in 3 brain sites evoked by acoustic and microwave stimuli. Loci in which potentials were observed were eighth cranial nerve, medial geniculate nucleus and primary auditory cortex. The effect of cochlear disablement on these potentials was evaluated. Potentials at all sites were abolished by cochlear damage. There were no differences between acoustic and microwave stimuli in this regard. Data are interpreted as supporting the contention that the microwave auditory effect is mediated at the periphery as are the effects of conventional acoustic stimuli.
Portal fibroblasts: Underappreciated mediators of biliary fibrosis.

Portal fibroblasts are an important yet often overlooked non-parenchymal cell population in the liver. They are distinct from hepatic stellate cells, yet like stellate cells differentiate in the setting of chronic injury to fibrogenic myofibroblasts, playing an important role in collagen production in the fibrotic liver. Portal fibroblasts are located adjacent to bile duct epithelia and thus play a particularly significant role in biliary fibrosis. New data suggest that they may also have key functions independent of fibrogenesis. This review will address the definition and characteristics of PF as well as their signaling pathways, interactions with the biliary epithelium, and contributions to liver pathobiology. We conclude that portal fibroblasts are an important and multifunctional non-parenchymal cell population in need of further study.
Maximum Likelihood Estimation from Linear Combinations of Discrete Probability Functions

Abstract In this article the problem of obtaining the maximum likelihood estimates of the parameters from a special type of linear combination of discrete probability functions is discussed. It is shown that when the sample is completely categorized the estimation problem is no more complicated that that of estimating the parameters of each of the component probability functions separately. When the sample is less than completely classified an iterative procedure must be used to obtain solutions to the likelihood equations and it is shown how the problem reduces to that of the full data case. A discussion of the asymptotic properties of the resulting estimators follows.
Facial attractiveness: is the whole more than the sum of its parts?

Background: In order for aesthetic surgery to participate in the movement toward evidence-based medicine, a system that quantifies aesthetic outcomes must be developed based on reliable and reproducible data. Previous studies have investigated the attractiveness of averaged (or composite) faces. Data has shown that these faces are deemed more attractive than their constituent faces. Objectives: The authors seek to elucidate the mechanism behind the phenomenon in which more attractive faces included in a composite increase the overall attractiveness rating. Methods: Ten composites, five male and five female, were generated with resources provided by the [www.faceresearch.org][1] research group. The five composites contained the top two, three, and five most attractive faces, a composite of all faces, and the five least attractive faces. An online survey was conducted in which participants were asked to rank each of the five faces in order of attractiveness. Results: Analysis of variance (ANOVA) on ranks was performed on the data provided by the 245 participants. Attractiveness increased from the top two to the top three to the top five composite faces, and then decreased from the top five to all faces to the bottom five composite faces. This trend was present and statistically significant (with a P value <.05) across all genders, ages, and races. Conclusions: This study provides statistically significant evidence that averaging more attractive faces, specifically the top 10% of a population, renders a more attractive composite face. This optimal composite face could potentially be a standard to which aesthetic surgical outcomes could be objectively compared. [1]: http://www.faceresearch.org
Flow Diversion Radial Artery Bypass Graft Coupled With Terminal Basilar Artery Occlusion for the Treatment of Complex Basilar Apex Aneurysms: Operative Nuances

Background A subset of basilar apex aneurysms are unsuitable for either primary microsurgical clipping or endovascular coiling. These complex aneurysms can be treated by terminal basilar artery occlusion, but only if collateral circulation is adequate. To circumvent these complications, a high-flow vertebral artery-posterior cerebral artery or middle cerebral artery-posterior cerebral artery bypass may be performed to create an adequate collateral circulation to allow treatment of the aneurysm by basilar artery occlusion and/or clipping. Objective To discuss the operative nuances of this approach in the case of a 47-year-old man with progressive hemiparesis resulting from brainstem compression from a giant, unruptured basilar apex aneurysm with absent posterior communicating artery collaterals and incorporation of bilateral superior cerebellar arteries and posterior cerebral arteries within the aneurysm neck. Methods The patient underwent a staged bypass from V3 to P2 coupled with terminal basilar artery occlusion. Results The patient initially presented as modified Rankin Scale score 2 with right hemiparesis. The aneurysm ruptured after the first stage of the operation, and the patient underwent a V3 to P2 bypass the next day. His postprocedural neurologic decline improved at the 14-month follow-up to modified Rankin Scale score 2, with substantial reduction in aneurysm size observed at 9 months. The outcomes for 3 other bypass cases for basilar apex aneurysms are also summarized. Conclusion : We discuss the indications, preoperative diagnostic workup, operative management, and postoperative outcomes in managing challenging basilar apex aneurysms. In our experience, high-flow bypass procedures with or without hunterian ligation in the treatment of these aneurysms are well tolerated with good long-term results.
Fundamentals of Quality and Safety in Diagnostic Radiology

The most fundamental aspects of quality and safety in radiology are reviewed, including a brief history of the quality and safety movement as applied to radiology, the overarching considerations of organizational culture, team building, choosing appropriate goals and metrics, and the radiologist’s quality “tool kit.”
Genes in drug abuse.

Because of the genome projects it will be possible to identify the changes in gene expression that are associated with drug abuse. The ultimate goal will be to determine the role and significance of the gene products. To date about 100 genes have been found with altered expression after administration of drugs. The development of new technologies such as microarrays will greatly facilitate finding such changes in expression. The rate at which levels of some gene products change is compatible with the time course of development of dependence in animals, but we must be able to establish a cause-effect relationship between genes and drug abuse, which this will be difficult. The product of the novel cocaine and amphetamine regulated transcript (CART) gene is a useful example where a gene product has been associated with drug abuse. CART was identified as an mRNA that changed in response to psychostimulant drug administration and injection of CART peptides into the ventral tegmental area produces psychostimulant-like effects. Definitive evidence, if obtainable, that specific genes are responsible for vulnerability to drug abuse could have dramatic effects on public health policy.
Central compartment and apical defect repair using synthetic mesh.

Pelvic organ prolapse is an increasingly common condition for women that has been challenging to treat due to high recurrence rates after surgical repair. The introduction of mesh-augmented prolapse repairs as a means to achieve more robust repairs had great initial promise. As more data emerge on outcomes and novel mesh complications, the when and where of mesh augmentation has become much less clear. This article reviews the relevant literature on the use of mesh in central and apical repairs. This includes a detailed look at the available data for vaginal mesh kits and several recent trials comparing mesh kits to traditional repairs. The article ends with a discussion of the recent U.S. Food and Drug Administration (FDA) safety communication on the use of transvaginal mesh in pelvic organ prolapse and the authors’ views of how practice may change in this new environment.
Measurements by geomagnetic induction of volume transport in a salt marsh drainage channel1,2

Volume transport of seawater through a salt marsh drainage channel is obtained by geomagnetic induction. The electric potential difference across the channel is interpreted in terms of water motion through the vertical component of the earth’s magnetic field. A model is formulated relating volume transport to induced potential differences and a salt bridge technique described for measuring the weak voltages. Calibration requires independent measurements of the volume transport. Using surface flow, rather than volume transport, for calibration results in method errors as large as 25%. Calibration against directly measured volume transport would reduce these errors.
Notch 1 activation in the molecular pathogenesis of T-cell acute lymphoblastic leukaemia

The chromosomal translocation t(7;9) in human T-cell acute lymphoblastic leukaemia (T-ALL) results in deregulated expression of a truncated, activated form of Notch 1 (TAN1) under the control of the T-cell receptor-beta (TCRB) locus. Although TAN1 efficiently induces T-ALL in mouse models, t(7;9) is present in less than 1% of human T-ALL cases. The recent discovery of novel activating mutations in NOTCH1 in more than 50% of human T-ALL samples has made it clear that Notch 1 is far more important in human T-ALL pathogenesis than previously suspected.
Long-term follow-up of patients with necrotizing enterocolitis

Abstract Background/Purpose: Despite the rise in the incidence of necrotizing enterocolitis (NEC), there is a paucity of data regarding long-term patient outcome. The authors examined functional outcome of infants with NEC (n = 103) treated at our institution between 1991 and 1995. Methods: The authors reviewed the medical records of infants who were treated both operatively and nonoperatively, n=103. Variables examined included gestational age, birth weight, Bell stage (I through III), operations performed, and mortality rate. Telephone interviews assessed school enrollment, developmental delay, bowel function, and nutritional status. Results: Children treated operatively had a lower gestational age than those in the nonoperative group. Likewise, birth weight in the operative group was significantly lower. Sixty-three percent of patients had stage III, and the remainder had stage II disease. The telephone response rate was 61%. Mean age at follow-up was 7.5 ± 2.5 years. All children ate by mouth. Nearly all children were toilet trained. All children were less than the 50th percentile for height and weight, and the majority (83%) were enrolled in school full time. Conclusion: Infants with stage II and III NEC who are treated operatively or nonoperatively have a favorable long-term outcome. J Pediatr Surg 37:1048-1050. Copyright 2002, Elsevier Science (USA). All rights reserved.
A comparison of the general circulations of the Northern and Southern Hemispheres based on satellite, multi-channel radiance data

Certain aspects of the general circulations of the Northern and Southern Hemispheres are compared using atmospheric structure obtained from Nimbus 3 Satellite Infrared Spectrometer (SIRS) data. Comparisons between the hemispheres of zonal and eddy available potential energy (AZ and AE) and zonal and eddy kinetic energy (KZ and KE) indicate that the ratios of AZ to AE and KZ to KE are larger in the Southern Hemisphere. The relative importance of standing and transient eddies in both hemispheres is investigated. The results show that standing eddies in the Southern Hemisphere contribute less to eddy available potential energy (AE) and eddy kinetic energy (KE) than in the Northern Hemisphere. The same type of inter-hemispheric distinction is true for the mid-latitude eddy heat flux. The distribution with latitude of the relative importance of standing and transient eddies is also studied. Horizontal eddy heat fluxes in the upper troposphere of both hemispheres are examined and in midlatitudes found to be approximately equal in magnitude when averaged over the summer and winter month. The Southern Hemisphere mid-latitude eddy heat flux is also shown to have significant longitudinal variations, apparently associated with the location of the southern continents.
MAPPING IN VIVO ASSOCIATIONS OF CYTOPLASMIC PROTEINS WITH INTEGRIN BETA 1 CYTOPLASMIC DOMAIN MUTANTS

Integrins promote formation of focal adhesions and trigger intracellular signaling pathways through cytoplasmic proteins such as talin, alpha-actinin, and focal adhesion kinase (FAK). The beta 1 integrin subunit has been shown to bind talin and alpha-actinin in in vitro assays, and these proteins may link integrin to the actin cytoskeleton either directly or through linkages to other proteins such as vinculin. However, it is unknown which of these associations are necessary in vivo for formation of focal contacts, or which regions of beta 1 integrin bind to specific cytoskeletal proteins in vivo. We have developed an in vivo assay to address these questions. Microbeads were coated with anti-chicken beta 1 antibodies to selectively cluster chicken beta 1 integrins expressed in cultured mouse fibroblasts. The ability of cytoplasmic domain mutant beta 1 integrins to induce co-localization of proteins was assessed by immunofluorescence and compared with that of wild-type integrin. As expected, mutant beta 1 lacking the entire cytoplasmic domain had a reduced ability to induce co-localization of talin, alpha-actinin, F-actin, vinculin, and FAK. The ability of beta 1 integrin to co-localize talin and FAK was found to require a sequence near the C-terminus of beta 1. The region of beta 1 required to co-localize alpha-actinin was found to reside in a different sequence, several amino acids further from the C-terminus of beta 1. Deletion of 13 residues from the C-terminus blocked co-localization of talin, FAK, and actin, but not alpha-actinin. Association of alpha-actinin with clustered integrin is therefore not sufficient to induce the co-localization of F-actin.
FURTHER DISCUSSION ON THE INCOMPRESSIBLE PRESSURE—DRIVEN FLOW IN A CHANNEL WITH POROUS WALLS

The unsteady velocity profiles for a pressure-driven Poiseuille flow in a channel with porous walls under mass transfer is analyzed and solved exactly. The steady state temperature distribution with viscous dissipation is also derived and solved exactly. The influences of mass transfer on transient velocity and state steady temperature profiles are presented and discussed. The wall heat transfer characteristics are also analyzed
The Role of Oceanic Heat Advection in the Evolution of Tropical North and South Atlantic SST Anomalies

Abstract The role of horizontal oceanic heat advection in the generation of tropical North and South Atlantic sea surface temperature (SST) anomalies is investigated through an analysis of the oceanic mixed layer heat balance. It is found that SST anomalies poleward of 10° are driven primarily by a combination of wind-induced latent heat loss and shortwave radiation. Away from the eastern boundary, horizontal advection damps surface flux–forced SST anomalies due to a combination of mean meridional Ekman currents acting on anomalous meridional SST gradients, and anomalous meridional currents acting on the mean meridional SST gradient. Horizontal advection is likely to have the most significant effect on the interhemispheric SST gradient mode through its impact in the 10°–20° latitude bands of each hemisphere, where the variability in advection is strongest and its negative correlation with the surface heat flux is highest. In addition to the damping effect of horizontal advection in these latitude bands, e...
Calibrated method for ultrasonic on-line monitoring of gradual wear during turning operations

Abstract On-line tool condition monitoring is essential for modern machining systems, especially in the case of precision and unmanned machining. Knowledge of the condition and the expected life of the tool are very important inputs for determining the optimal machining parameters. Previous efforts have indicated that ultrasonic gaging methods can be used to directly measure in-process gradual tool wear during turning operations. Good correlation was shown between the level of gradual wear and the ultrasonic signals. However, the correlation was tool dependent. This was mainly attributed to variations in the tool materials and inconsistent coupling of the transducer to the tools. This paper describes a robust method for on-line gradual wear monitoring using normalized ultrasonic signals. A consistent calibration mark, cut in the lower comer of the tool nose, is used to generate a calibration echo. The calibration echo is affected by the same variations as that of the gradual wear and is used to normalize the nose and flank echoes. Experiments under various cutting conditions showed that the gradual wear measurements can be made tool independent by normalizing the measurements with the calibration mark. In addition, the variations in the signals which were previously reported are also eliminated.
Cytogenetic investigations on radiation and chemically induced dominant lethal mutations in oocytes and sperm of the screw-worm fly

Abstract Adult females containing oocytes in early prophase or early anaphase of the first meiotic division, and day-old males containing mature sperm were exposed to γ-radiation or the alkylating agent, 2,4,6-tris (1-aziridinyl)-s.-triazine (= tretamine). The doses used induced nearly 100% dominant lethals in the reproductive cells. Treated insects were crossed with untreated ones. Eggs were collected and fixed after different periods of development at room temperature. Stained whole-mounts of the embryos were studied to determine: (1) The kind of chromosome aberrations associated with dominant lethal mutations, (2) the stage of development at which the chromosome aberrations appeared, (3) the stage at which development ceased in embryos containing dominant lethal mutations of either maternal or paternal origin, (4) whether damage induced by tretamine was cytologically similar to that induced by ionizing radiations. Dominant lethal mutations are characterized by the presence of chromosome bridges and fragments between dividing nuclei in the embryo, but the stage of development at which these first appear differs with the type of mutagen used. The damage produced by irradiation of meiotic oocytes is evident during the first and second meiotic divisions (which are completed after oviposition) and continues into the early cleavage divisions, at which time development ceases. After treatment of meiotic oocytes with tretamine, the majority of the subsequent meiotic divisions appear normal and the detection of most of the chromosomal damage is first possible in cleavage divisions, or after the treated nucleus undergoes one replication of chromatin material. Treatment of mature sperm with either γ-rays or tretamine does not prevent syngamy. Chromosome aberrations become evident at the first cleavage division. It is obvious that chromosome-breakage phenomena formed the basis of dominant lethality in these cells. Each of these treatments stops embryonic development generally after only a few cleavage divisions. Various types of abnormalities were observed in the embryos. The relevance of these observations to the mode of action of the mutagens, the chromosomal basis of dominant lethality, and the differential sensitivity of the three types of germ cells to these mutagens are discussed.
Perimetry: Variable Factors Influencing the Breadth of the Color Fields

This is the first of a series of papers upon perimetry, and deals particularly with the factors upon which thresholds of light and color perception depend. It calls attention to the irregularities of color sensitivity for different colors and for different meridians of the visual field.
MITRAL BALL-VALVE PROSTHESIS. DYNAMIC AND CLINICAL EVALUATION.

Flow dynamic studies were performed in a mechanical pulse duplicator with Starr-Edwards ball valves. It was shown that the "effective orifice" of the ball valve is less than the measured orifice of the cage of the valve. The orifice is decreased to 83 per cent of the measured orifice in the smaller and to 89 per cent in the larger valves. These measurements corresponded well with the measurements of the "effective orifice" of the valve implanted in patients who were examined by left and right heart catheterization and left ventricular angiocardiograms several months after placement of the valve. The closing regurgitation found in early systole in the mechanical system appears to be negligible in patients. Left ventricular angiograms did not show reflux of dye into the left atrium through the valve cage. The size of the mitral annulus in patients was measured from left ventricular angiograms. The size of the mitral ball valve prosthesis which the mitral annulus will accommodate could be predicted with good accuracy from these measurements.
Nanoassembly of Surfactants with Interfacial Drug-Interactive Motifs as Tailor-Designed Drug Carriers

PEGylated lipopeptide surfactants carrying drug-interactive motifs specific for a peptide-nitroxide antioxidant, JP4-039, were designed and constructed to facilitate the solubilization of this drug candidate as micelles and emulsion nanoparticles. A simple screening process based on the ability that prevents the formation of crystals of JP4-039 in aqueous solution was used to identify agents that have potential drug-interactive activities. Several protected lysine derivatives possessing this activity were identified, of which α-Fmoc-e-t-Boc lysine is the most potent, followed by α-Cbz- and α-iso-butyloxycarbonyl-e-t-Boc-lysine. Using a polymer-supported liquid-phase synthesis approach, a series of synthetic lipopeptide surfactants with PEG headgroup, varied numbers and geometries of α-Fmoc or α-Cbz-lysyl groups located at interfacial region as the drug-interactive domains, and oleoyl chains as the hydrophobic tails were synthesized. All α-Fmoc-lysyl-containing lipopeptide surfactants were able to solubilize JP4-039 as micelles, with enhanced solubilizing activity for surfactants with increased numbers of α-Fmoc groups. The PEGylated lipopeptide surfactants with α-Fmoc-lysyl groups alone tend to form filamentous or wormlike micelles. The presence of JP4-039 transformed α-Fmoc-containing filamentous micelles into dots and barlike mixed micelles with substantially reduced sizes. Fluorescence quenching and NMR studies revealed that the drug and surfactant molecules were in close proximity in the complex. JP4-039-loaded emulsion carrying α-Cbz-containing surfactants demonstrated enhanced stability over drug-loaded emulsion without lipopeptide surfactants. JP4-039 emulsion showed a significant mitigation effect on mice exposed to a lethal dose of radiation. PEGylated lipopeptides with an interfacially located drug-interactive domain are therefore tailor-designed formulation materials potentially useful for drug development.
Adhesion of viscoelastic materials to rigid substrates

Measurements have been made of the forces required to peel a thin layer of a model visco-elastic adhesive off a rigid substrate. Over a wide range of temperature and rate of peel the results were found to yield a single master relation in terms of peel rate when reduced to a reference temperature by means of the Williams, Landel & Ferry rate–temperature equivalence for viscous materials. The relations obtained were complex, however, with two main features: a cohesive–adhesive failure transition at low rates and a sharp decrease in peel strength at high rates. The first effect is shown to be due to a change in the deformation process in the adhesive, from a liquid-like to a rubber-like response. An approximate relation between peel strength and the tensile stress–strain behaviour of the adhesive is developed in terms of a single empirically-determined parameter, the interfacial bond strength. Values of this parameter are deduced for several substrates. Measurements of peeling under hydrostatic pressure showed that cavitation of the adhesive did not occur in these experiments. The second effect is shown to be due to the transition from a rubber-like to a glass-like response of the adhesive. It is also shown to depend on the way in which separation is effected. Some general principles governing the mode of failure and the development of maximum peel strength are outlined.
Computer simulation and analysis of high‐resolution electron microscope images and diffraction patterns with partial coherence, hollow cone illumination, and virtual apertures

A general method for computing high-resolution conventional transmission electron microscope images and diffraction patterns, when there are different types of partially coherent illumination conditions, is described. Examples of convergent beam, hollow cone, and virtual aperture illumination conditions are given in the context of interpreting image features. A comparison of real and computed diffraction patterns shows that, in practice, many innovative imaging modes are possible, which can be verified prior to real microscope experiments.
Disintegrin-like domain of glycoprotein B regulates Kaposi’s sarcoma-associated herpesvirus infection of cells

Kaposi's sarcoma-associated herpesvirus (KSHV) glycoprotein B (gB) is a lytic structural protein expressed on the envelope of mature virions and on the membrane of cells supporting lytic infection. In addition to this viral glycoprotein’s interaction with integrins via its RGD (Arg-Gly-Asp) motif, KSHV gB possesses a disintegrin-like domain (DLD), which binds integrins as well. Prior to this study, there has been minimal research involving the less common integrin-binding motif, DLD, of gB as it pertains to herpesvirus infection. By using phage display peptide library screening and molecular biology techniques, the DLD of KSHV gB was shown to interact specifically with non-RGD binding α9β1 integrins. Similarly, monitoring wild-type infection confirmed α9β1:DLD interactions to be critical to successful KSHV infection of human foreskin fibroblast (HFF) cells and human dermal microvascular endothelial cells (HMVEC-d) compared with 293 cells. To further demonstrate the importance of the DLD of gB in KSHV infection, two recombinant virus constructs were generated using a bacterial artificial chromosome (BAC) system harbouring the KSHV genome (BAC36): BAC36ΔD-KSHV (lacking a functionally intact DLD of gB and containing an introduced tetracycline cassette) and BAC36.T-KSHV (containing an intact DLD sequence and an introduced tetracycline cassette). Accordingly, BAC36ΔD-KSHV presented significantly lower infection rates in HFF and HMVEC-d cells compared with the comparable infection rates achieved by wild-type BAC36-KSHV and BAC36.T-KSHV. Thus, the present report has delineated a critical role for the DLD of gB in KSHV infection, which may lead to a broader knowledge regarding the sophisticated mechanisms utilized by virus-encoded structural proteins in KSHV entry and infection.
Comparison of electric and growth responses to excision in cucumber and pea seedlings. I. Short-distance effects are a result of wounding.

The local electric response to stem excision in both pea epicotyls and cucumber hypocotyls is a depolarization of the cells in the wound area. If we define wound area as the region of local depolarization, we find that it extends for approximately 10 mm from the cut or wound site in pea epicotyls, whereas it can reach up to 40 mm in cucumber hypocotyls. The wound-induced depolarization in pea cells is transient, reaching its maximal amplitude within 1-2 min, whereas in cucumber cells this depolarization is more sustained. A third difference between wound responses in pea and cucumber is the intermittent appearance of spikes, i.e. very short, rapidly reverted depolarizations which frequently accompany the basic depolarization in cucumber but not in pea cells. These spikes can propagate in both directions along the hypocotyl axis. The cause of the different responses of pea and cucumber cells is unknown. A possible explanation might be found in different degrees of electrical cell coupling in the two species. This possibility was investigated in cucumber hypocotyls by measuring the cell input resistance (R(in)) of epidermal cells at various axial distances from the cut. Shorter distances increase the likelihood of shunting the cell membrane resistance through the shortened symplastic path to the cut surface. With a series of cuts made at decreasing distances from the measured site, cell depolarization increased without comparable changes in R(in). Two conclusions were drawn. Firstly, wound-induced depolarizations are not brought about by shunting of the cell resistance in the wound area. Secondly, the depolarization is probably not carried by ion channels but may be caused by an inhibition of proton pump activity. Parallel to its depolarization effect on the membrane potential, excision led to a severe and sustained decline in the cucumber hypocotyl growth rate only when carried out sufficiently close to the growing region (45 mm from the hook). Similar excision in pea epicotyls failed to change the growth rate. Both electrical and growth data support the concept that the high and sustained responsiveness of cucumber seedlings to wounding is caused by a particular sensitivity of their proton pump mechanism.
Does Time Matter? Comparing Trajectory Concordance and Covariate Association Using Time-Based and Age-Based Assessments:

Much criminological research has used longitudinal data to assess change in offending over time. An important feature of some data sources is that they contain cross-sections of different aged individuals followed over successive time periods, thereby potentially conflating age and time. This article compares the substantive conclusions about the relationship between age and offending based on trajectory modeling analyses by time-of-assessment versus age-at-assessment. Analyses of a large sample of serious youthful offenders followed for 7 years consisted of estimation of group-based offending trajectories and multinomial logistic regressions examining how risk/protective factors distinguished between offending trajectories. Findings revealed that concordance using measurement approaches was strong at relatively high and low levels of antisocial behavior, with greater ambiguity between these two offending extremes. The relation of risk/protective factors to various trajectories was substantively similar a...
TESTING WHY THE SEX OF THE MATERNAL PARENT AFFECTS SEEDLING SURVIVAL IN A GYNODIOECIOUS SPECIES

In gynodioecious plants, seed offspring from hermaphrodites often perform less well than those from females. This lower performance sometimes can be attributed to inbreeding by hermaphrodites or to relatively greater provisioning of individual seeds by females. However, these hypotheses are not explanatory when only outcrossing occurs and when individual seeds of the two morphs are equally well provisioned. Three hypotheses may explain the lower fitness of seed offspring from hermaphrodites in such cases. The morphology hypothesis states that the op- portunity for gametophytic selection is lower within flowers of hermaphrodites compared to flowers on females, because the perfect flowers of hermaphrodites are relatively short-styled. The cytotype hypothesis states that the performance difference is directly caused by an individual's cytotype, whose frequency in the population may differ for the two sex morphs. The pleiotropy hypothesis states that negative pleiotropic effects of nuclear restorer alleles or alleles hitchhiking with them are expressed more often by offspring from hermaphrodites. We performed two experiments using the gynodioecious plant Silene acaulis to contrast these hypotheses. In our first experiment we contrasted the morphology and pleiotropy hypotheses by performing controlled pollinations and subsequently planting seeds in both the greenhouse and field. Hermaphrodites ofS. acaulis can produce both pistillate and perfect flowers, which allowed us to determine whether flower morphology affects offspring survivorship independent of the sex of the maternal parent. We found that neither seed mass nor germination differed between seeds from females and hermaphrodites. Offspring from pistillate flowers on hermaphrodites did not differ significantly in their survival compared to offspring from perfect flowers on hermaphrodites, but had lower survivorship compared to offspring from pistillate flowers on females, refuting the morphology hypothesis. In a second experiment, we compared offspring survival of full-sibling pairs of females and hermaphrodites (who shared the same cytoplasm) to contrast the cytotype and pleiotropy hypotheses. We found that seed offspring from females and hermaphrodites that shared the same cytoplasm differed in their survival, which is counter to the prediction of the cytotype hypothesis. In both experiments, the sex of the maternal parent significantly affected offspring survival, with seed offspring from hermaphrodites surviving less well than those from females. These results support the pleiotropy hypothesis. We conclude by discussing alternative ways of thinking about negative pleiotropic effects of nuclear restorers or ''the cost of restoration.''
The synthetic gene designer: a flexible Web platform to explore sequence space of synthetic genes for heterologous expression

"Codon optimization" is a general approach that seeks to improve heterologous expression when a gene is moved into a foreign genome that exhibits different codon usage from its native genome. However, it is still unclear exactly what it means to optimize codons for protein expression: diverse interpretations exist, and exploratory research continues. Thus, to facilitate flexible redesign of genes for heterologous expression, we have developed a bona fide web application: the "synthetic gene designer". Compared with existing codon optimization software, the synthetic gene designer provides greater flexibility in several key features of codon optimization strategy. The software, together with online tutorials and help, is available at http://www.evolvingcode. net/codon/sgd.php.
A “Model to Model” Collaborative Perception Methodology for Distributed Design

To solve the problem of collaborative engineering changes of models distributed in heterogeneous design platforms, a “model to model” perception methodology is proposed in this paper. A self-manage...
Detecting signal-overshoots for reliability analysis in high-speed system-on-chips

The rising level of complexity and speed of SoC makes it increasingly vital to test adequately the system for signal integrity. Voltage overshoot is one of the integrity factors that has not been sufficiently addressed for the purpose of testing and reliability. Overshoots are known to inject hot-carriers into the gate oxide and cause permanent degradation of MOSFET transistors' performance. This performance degradation creates a serious reliability concern. Unfortunately, accurate parasitic extraction and simulation to detect the interconnect problems is very time consuming and very sensitive to the circuit characteristics and thus is not practical for large SoC. This paper presents a built-in chip methodology to detect and measure the signal overshoots occurring on the interconnects of high-speed system-on-chips. This built-in test strategy does not require external probing or signal waveform monitoring. Instead, the overshoot detector cells monitor signals received by a core (e.g. from the system bus) and record the occurrence of overshoots over a period of operation. The overshoot information accumulated by these cells can be compressed and scanned out efficiently And inexpensively for final quality grading, reliability analysis and diagnosis.
Does 'anybody' really want (or need) vehicle navigation aids?

The author asserts that developers of vehicle navigation aids should not persist in using an intradisciplinary approach to solving an interdisciplinary problem. It is demonstrated that research in differing disciplines can be intertwined, and that theories and models often can be borrowed. It is suggested that though interdisciplinary results can be supporting, caution should be taken when interpreting these. The author reviews current research in spatial knowledge acquisition in computer science, psychology, and geography, and how these models can enhance vehicle navigation aid development. Current research in cognitive psychology and environmental behavior related to the presentation of driving instructions to drivers is discussed. >
Intracavity-pumped 2.09-μm Ho:YAG laser

The 2.09-microm Ho:YAG (5)I(7) ? (5)I(8) laser transition is intracavity pumped by a Tm:YAG laser. Separate Tm:YAG and Ho:YAG crystals share a single laser cavity, the Tm:YAG crystal is pumped at 785 nm, and the resulting 2.01-microm Tm(3+) laser emission pumps the Ho:YAG crystal. The slope efficiency of the 2.09-microm Ho(3+) laser output is 42% of the absorbed 785-nm pump power.
Cholesterol trafficking and distribution

Sterols are a critical component of cell membranes of eukaryotes. In mammalian cells there is approximately a six-fold range in the cholesterol content in various organelles. The cholesterol content of membranes plays an important role in organizing membranes for signal transduction and protein trafficking as well as in modulating the physiochemical properties of membranes. Cholesterol trafficking among organelles is highly dynamic and is mediated by both vesicular and non-vesicular processes. Several proteins have been proposed to mediate inter-organelle trafficking of cholesterol. However, several aspects of the mechanisms involved in regulating trafficking and distribution of cholesterol remain to be elucidated. In the present chapter, we discuss the cellular mechanisms involved in cholesterol distribution and the trafficking processes involved in maintaining sterol homoeostasis.
Abstinence-Induced Changes in Self-Report Craving Correlate with Event-Related fMRI Responses to Smoking Cues

Drug cues have been shown to activate brain regions involved in attention, motivation, and reward in addicted users. However, as studies have typically measured responses in only one state (ie drug abstinence), it is unclear whether observed activations represent amplification by abstinence or stable responses. Thus, the present study was designed to evaluate the stability of event-related responses to visual drug cues in dependent smokers (n=13) using event-related functional magnetic resonance imaging measures. Imaging was conducted following smoking as usual and following overnight abstinence, and self-reported craving measures were obtained before, during, and after scanning. Analysis of hemodynamic response (HDR) amplitudes in each of 13 regions of interest revealed larger responses to smoking compared to control cues in ventral anterior cingulate gyrus (vACG) and superior frontal gyrus. Responses to smoking cues in these and all other regions revealed no effects of abstinence/satiety, thus supporting the notion that cue-elicited brain responses are relatively stable. However, while the abstinence manipulation did not alter group-level responses to smoking cues, at the individual level, abstinence-induced changes in craving (abstinence minus satiety) were positively correlated with changes in HDR amplitude to smoking cues in frontal regions including left inferior frontal gyrus, left vACG, and bilateral middle frontal gyrus. These results suggest that brain responses to smoking cues, while relatively stable at the group level following short-term abstinence, may be modulated by individual differences in craving in response to abstinence-particularly in regions subserving attention and motivation.
RELAY: static race detection on millions of lines of code

Data races occur when multiple threads are about to access the same piece of memory, and at least one of those accesses is a write. Such races can lead to hard-to-reproduce bugs that are time consuming to debug and fix. We present RELAY, a static and scalable race detection analysis in which unsoundness is modularized to a few sources. We describe the analysis and results from our experiments using RELAY to find data races in the Linux kernel, which includes about 4.5 million lines of code.
First principles evaluation of the permanent dipole moments of the states in zinc blende semiconductors

A simple first-principle analytical derivation of the permanent matrix elements of the dipole moment responsible for most of the resonant nonlinearities in III-V and II-VI semiconductors is presented.
THE IMPORTANCE OF ACCURATE CURVE NUMBERS IN THE ESTIMATION OF STORM RUNOFF

: Storm runoff as calculated by the runoff curve number method is shown to be of varying sensitivity to both input rainfall and curve number. Using an assumed input error of 10%, a runoff error chart is given. Up to about 9 inches of rainfall, runoff is more sensitive to curve number than to rainfall. The importance of accurate curve number selection in this range is stressed.
Implementing Speculative Parallelism in Possible Computational Worlds

Most constructs for speculative parallelism have been devised in an ad hoc way, with quite particular applications in mind. What diverse instances of speculative computation have in common is the notion of executing code conditional on a future condition or event.