cssi/SciSciGPT-SciSciNet huggingface dataset:
Asymmetric mutation around the recombination break point of immunoglobulin class switch sequences on extrachromosomal substrates

Junctions at class switch recombination sites in the genome are characterized by a unique sequence feature. Nucleotide substitutions and small deletions are common on either of the two sides of the switch junction, but not on both together. We have previously reported an extrachromosomal substrate assay system for analyzing the recombination of class switch sequences. Here we have sequenced nine junctions on each side of the break point and compared these to 17 recombination junctions of control substrates from the same cells. Five of the nine switch recombination junctions have nucleotide substitutions and deletions, with multiple nucleotide changes being more common. Furthermore, mutations were found only on a single side of the junction, just as for the recombination of switch sequences in the genome. In contrast, only one of 17 control substrate junctions had a mutation, and this was a single nucleotide insertion. This difference is highly significant (P < 0.00007) and indicates that the fundamental recombination mechanism is likely to be similar for switch sequences in the chromosome and on minichromosome substrates.
The charge and energy spectra of heavy cosmic-ray nuclei

A charged particle detector array flown on a high altitude balloon has detected and measured some 3×104 cosmic-ray nuclei withZ≥12. The charge spectrum at the top of the atmosphere for nuclei withE>650 MeV·n−1 and the energy spectrum for 650≤E<1800 MeV·n−1 are reported and compared with previously published results. The charge spectrum at the ‘source’ of cosmic rays is deduced from these data and compared with a recent compilation of ‘galactic’ abundances.
G Protein Subunits and Cell Proliferation

Heterotrimeric, guanine nucleotide binding proteins, known as G proteins, provide signaling mechanisms for the serpentine family of receptors. Recent studies indicate that the α- as well as the βγ-subunits of the G proteins are involved in the regulation of several cellular responses. Some of these responses proved to be critical for the regulation of cell growth and differentiation. Studies using the constitutively activated mutants of the Gα subunits and the overexpression of Gβγ subunits have indicated that these different subunits regulate cell proliferation through diverse signaling pathways involving distinct low molecular weight GTPases and specific protein kinases. The integrated networking between these different pathways finally defines the coordinated regulation of cell proliferation. This review briefly summarizes our present understanding of the different signaling mechanisms involved in the regulation of cell proliferation by the different Gα and Gβγ subunits.
Factors influencing tissue culture responses of mature seeds and immature embryos in turf‐type tall fescue

In an effort to optimize tissue culture responses of turf-type tall fescue for genetic transformation, the effects of five culture medium supplements on tissue culture responses were investigated with immature embryos and mature seeds of an elite cultivar, ‘Coronado’, as explant tissues. For both explants, calli induced on 6-benzylaminopurine (BAP)-containing medium had significantly improved regeneration ability. The optimal concentration of BAP for the induction of regenerable callus from mature seeds was 0.1 mg/l. Thidiazuron also improved callus regeneration frequency of mature seeds. Casein hydrolysate, L-proline and myo-inositol improved callus induction of immature embryos but not mature seeds. They did not improve callus regeneration frequencies with either explant tissue. By simply slicing the mature seeds into two halves longitudinally, the callus induction frequencies, as well as the corresponding overall plant regeneration frequencies, were increased approximately three- to six-fold in all three combinations of 2,4-dichlorophenoxyacetic acid and BAP in callus induction media.
Neutron total cross-sections at intermediate-energies

Pulsed-beam time-of-flight techniques are used in a transmission measurement with a continuous spectrum of neutrons to determine neutron total cross sections with good precision up to 600 MeV. Neutrons are produced by spallation of the 800 MeV proton beam from the Los Alamos Meson Physics Facility accelerator incident on a thick, heavily shielded tungsten target at the Weapons Neutron Research facility at Los Alamos National Laboratory. Transmission measurements were completed for fifteen elements with 9\ensuremath{\le}A\ensuremath{\le}209 and three isotopically enriched samples of $^{40}\mathrm{Ca}$, $^{90}\mathrm{Zr}$, and $^{208}\mathrm{Pb}$. Principal features of the experiment are the intensity and time structure of the neutron source, tight collimation of the neutron beam line, good geometry, rapid cycling of the samples, stable electronics, and a small, fast neutron detector. Errors due to counting statistics were generally less than 1% for each of several hundred energy bins for each target. The measurements represent steps in the development of a neutron-nucleus optical potential at intermediate energy and important input for the clarification of isovector effects in the nucleon-nucleus interaction. The data also provide insight into the long-standing discussion of mean free paths of the nucleon in the nucleus.
Regional specification during embryogenesis in the craniiform brachiopod Crania anomala.

Abstract A fate map has been constructed for the embryo of Crania. The animal half of the egg forms the ectodermal epithelium of the larva's apical lobe. The vegetal half of the egg forms endoderm, mesoderm, and the ectoderm of the mantle lobe. The vegetal pole is the site of gastrulation; this site becomes the posterior ventral region of the mantle lobe of the larva. The plane of the first cleavage goes through the animal–vegetal axis of the egg; it bears no relationship to the future plane of bilateral symmetry of the larva. The timing of regional specification was examined by isolating animal, vegetal, or meridional halves from oocytes, eggs, or embryos from prior to germinal vesicle breakdown through gastrulation. Animal halves isolated from oocytes formed either the epithelium of the apical lobe or a larva with all three germ layers. Animal halves isolated from unfertilized eggs and eight-cell embryos formed only apical lobe epithelium. Beginning at the blastula stage, animal halves formed mantle in addition to apical lobe epithelium. In animal halves isolated after gastrulation, the mantle lobe was always truncated. Vegetal halves isolated at all stages prior to gastrulation gastrulated and formed apical and mantle lobes with endoderm and mesoderm; however, the relative size of the apical lobe that formed decreased substantially when vegetal halves were isolated at later developmental stages. When meridional halves were isolated from unfertilized eggs and two- to four-cell embryos, both halves frequently formed normally proportioned larvae. Beginning at the blastula stage, a number of pairs frequently had a member that lacked dorsal setae on its mantle lobe while the other member of the pair formed setae, indicating that the dorsoventral axis had been set up. The process of regional specification in Crania is compared to those of Discinisca and Glottidia in the brachiopod subphylum Linguliformea and Phoronis in the phylum Phoronida.
A New Fixed Point Iteration to Find Percentage Points for Distributions on the Positive Axis

In this article, we apply a fixed point approach to derive an iterative method that converges quadratically to any percentage point for a wide variety of commonly used distributions on the positive axis, often with no restriction on the starting point.
Brief Psychosocial–Behavioral Intervention With Antidepressant Reduces Poststroke Depression Significantly More Than Usual Care With Antidepressant Living Well With Stroke: Randomized, Controlled Trial

Background and Purpose— Depression after stroke is prevalent, diminishing recovery and quality of life. Brief behavioral intervention, adjunctive to antidepressant therapy, has not been well evaluated for long-term efficacy in those with poststroke depression. Methods— One hundred one clinically depressed patients with ischemic stroke within 4 months of index stroke were randomly assigned to an 8-week brief psychosocial–behavioral intervention plus antidepressant or usual care, including antidepressant. The primary end point was reduction in depressive symptom severity at 12 months after entry. Results— Hamilton Rating Scale for Depression raw score in the intervention group was significantly lower immediately posttreatment (P<0.001) and at 12 months (P=0.05) compared with control subjects. Remission (Hamilton Rating Scale for Depression <10) was significantly greater immediately posttreatment and at 12 months in the intervention group compared with the usual care control. The mean percent decrease (47%±2...
Culinary Education and Computer Technology: A Longitudinal Study

Using survey methodology this study compared 1996 and 2001 culinary educator sample perceptions of current and future computer technology use in 14 categories of general and industry computer applications and eight questions about the respondents programs technology requirements. Also four questions asked respondents to rate recipe/ inventory systems used in their programs. There is a discussion that considers changes in educator perceptions of program technology requirements and student current and future application usage. In general, programs were significantly increasing and planning to increase technology curricula in the 2001 sample. In general, both current and future technology use by culinary students is increasing with ease of student and faculty use the most important attributes of recipe/inventory systems. The respondents felt that computer use is considered essential for culinary graduates and that a variety of applications should be integrated into the information system of the culinary prog...
Kinetics of capture of colloidal particles in packed beds under attractive double layer interactions

Abstract The kinetics of capture of suspended colloidal particles in a packed bed of granular material in the presence of attractive double layer interactions have been investigated. Colloid deposition experiments were carried out with positively charged polystyrene latex colloids and negatively charged glass beads packed in a laboratory scale column. A notable increase in colloid deposition rates was observed when the ionic strength of the aqueous solution was reduced from 0.1 M to a value of 10−6−10−5 M. The experimental results were generally in good agreement with theoretical deposition rates, which were calculated from a numerical solution of the convective diffusion equation with colloidal and hydrodynamic interactions fully incorporated. The enhancement of the colloid deposition rates is attributed to the increase in the range and magnitude of the attractive double layer interactions as the ionic strength decreases. When attractive double layer interactions extend to large distances from the collector surface, the transport of particles toward the collector increases beyond that of pure convective diffusion, and, as a result, colloid deposition rates also increase.
Interactions between Subunits of the Human Epithelial Sodium Channel

The human epithelial sodium channel (hENaC) mediates Na+ transport across the apical membrane of epithelia, and mutations in hENaC result in hypertensive and salt-wasting diseases. In heterologous expression systems, maximal hENaC function requires co-expression of three homologous proteins, the alpha, beta, and gammahENaC subunits, suggesting that hENaC subunits interact to form a multimeric channel complex. Using a co-immunoprecipitation assay, we found that hENaC subunits associated tightly to form homo- and heteromeric complexes and that the association between subunits occurred early in channel biosynthesis. Deletion analysis of gammahENaC revealed that the N terminus was sufficient but not necessary for co-precipitation of alphahENaC, and that both the N terminus and the second transmembrane segment (M2) were required for gamma subunit function. The biochemical studies were supported by functional studies. Co-expression of gamma subunits lacking M2 with full-length hENaC subunits revealed an inhibitory effect on hENaC channel function that appeared to be mediated by the cytoplasmic N terminus of gamma, and was consistent with the assembly of nonfunctional subunits into the channel complex. We conclude that the N terminus of gammahENaC is involved in channel assembly.
The leaching of gold, silver and their alloys in alkaline glycine–peroxide solutions and their adsorption on carbon

Abstract The leaching of gold and silver in a pH modified glycine solution in the presence of hydrogen peroxide was investigated. It was found that this lixiviant system can dissolve gold and/or silver under neutral and alkaline conditions at ambient to moderately elevated temperatures (23–60 °C). The gold leaching rate in solutions containing 0.5 M glycine and 1% peroxide at pH 11 after 48 h of leaching was found to be 0.322 μmol/m 2 s, which is comparable to gold leaching rate after six days in thiosulphate–EDTA or thiosulphate–oxalate systems in the presence of thiourea (0.22–0.25 μmol/m 2 s). In alkaline glycine–hydrogen peroxide solutions, it has been found that gold leach rate from gold–silver (50% Ag) alloy is about 6 times higher than rate from pure gold and the silver leach rate was 0.247 μmol/m 2 s. An induction period of 48 h was noted for rolled precious metal foils, after which leaching rapidly accelerated. The reaction rate sensitivity to temperature can be explained by a mechanism that is chemical reaction controlling rather than mass transfer controlling as found for cyanide leaching. Precious metal dissolution rates increased with increased glycine concentration, increased silver content, and increasing pH (up to pH 11). The gold–glycinate complex was found to effectively load on activated carbon up to 13.2 g Au /kg carbon in 4 h.
Surface compression of light adsorbates inside microporous PFA-derived carbons

Abstract Surface compression is a phenomenon in which strong solid–fluid interactions compress the adsorbate molecules on a surface to a point that lateral repulsion forces appear. In this work, this phenomenon was studied for high pressure adsorption of a collection of light gases on polyfurfuryl alcohol (PFA)-derived carbons. The carbons were mostly microporous with mean pore sizes ranging from 5 to 8 A. Surface and lateral interactions were decoupled by transforming the adsorption isotherms into Ono–Kondo coordinates. This analysis revealed substantial loss of kinetic energy of hydrogen inside the carbon micropores. Inelastic Neutron Scattering (INS) indicated that there was indeed a hindrance to the rotational motion of H2 molecules inside the microporous carbon. Extensive analysis using heavier gases showed the observed change in the nature of the lateral forces during adsorption process. Adsorption began with attractive lateral forces; then as the pressure increased and even at low pressures repulsive forces emerged and as the adsorption proceeded the repulsive forces became more dominant. These effects were more pronounced inside small micropores. We believe that these lateral forces can also contribute to the drop in energetics of adsorption with gas loading as seen in heat of adsorption profiles.
Messenger RNA in rat liver polyribosomes: evidence that it exists as ribonucleoprotein particles.

Abstract After a 40-minute labeling period with a radioactive RNA precursor, the majority of the labeled RNA of a polyribosome preparation from rat liver cytoplasm is heterogeneous in size, non-ribosomal in base composition, and is directly associated with polyribosomes. On the basis of these and other criteria it can tentatively be identified as mRNA. The messenger RNA molecules can be released from polyribosomes by treatment with EDTA, and they are released not as naked strands but in association with less dense material, presumably protein, as ribonucleoprotein particles of heterogeneous sedimentation coefficient from 20 s to greater than 100 s and of heterogeneous buoyant density in CsCl from about 1.35 g/cm3 to 1.55 g/cm3. The mRNA-containing particles released from polyribosomes are in many ways similar to newly synthesized mRNA-containing particles found free (unassociated with polyribosomes) in the nucleus and in the cytoplasm, and it is postulated that mRNA is transferred from the nucleus as ribonucleoprotein particles, which are incorporated into polyribosomes. We speculate that the protein the mRNA carries with it from the nucleus into the polyribosome may serve to modulate protein synthesis at the translational level.
Impact of First-Grade Factors on the Growth and Outcomes of Urban Schoolchildren's Primary-Grade Writing.

The purpose of this study was to investigate predictors of early writing for low-income, urban students. Drawing on research and theory characterizing literacy development as a complex, integrative process, the author analyzed growth in the descriptive writing of students in Grades 1-3. The participants were 309 low-income children enrolled in 16 urban elementary schools. Descriptive writing samples were collected yearly as students progressed from Grades 1-3. Individual growth modeling indicated that student background, literacy skill, 1st-grade teacher, and 1st-grade classroom environment were predictors of writing quality and output. The results illustrate the complexity of early writing development and signal the importance of a comprehensive, developmental model of writing.
Considerations in Aesthetic Eyelid Surgery

background . Successful aesthetic eyelid surgery is based upon multiple complex factors that, when put together, yield a pleasing result. Beauty is inherently related to normal eyelid function and symmetry. objective . To review the critical issues facing the aesthetic surgeon, and to propose a systematic method of assessing the patient preoperatively. methods . This article first examines the general considerations for aesthetic eyelid surgery, followed by specific concerns within each anatomic area. results and conclusion . The critical task in aesthetic eyelid surgery is to reconstitute or preserve the normal structure and function of the eyelids. This is especially true in the multicontoured areas. It is essential for the surgeon to define the problems in a hierarchal fashion, and plan the surgery accordingly. Thus, not all patients can achieve the desired results in one sitting. The goal of aesthetic surgery is to avoid the telltale signs of surgery and to help the patient attain a youthful and energetic appearance for his or her age bracket. J Dermatol Surg Oncol 1992;18:1081–1095.
Inappropriate use of bivariable analysis to screen risk factors for use in multivariable analysis

The use of bivariable selection (BVS) for selecting variables to be used in multivariable analysis is inappropriate despite its common usage in medical sciences. In BVS, if the statistical p value of a risk factor in bivariable analysis is greater than an arbitrary value (often p = 0.05), then this factor will not be allowed to compete for inclusion in multivariable analysis. This type of variable selection is inappropriate because the BVS method wrongly rejects potentially important variables when the relationship between an outcome and a risk factor is confounded by any confounder and when this confounder is not properly controlled. This article uses both hypothetical and actual data to show how a nonsignificant risk factor in bivariable analysis may actually be a significant risk factor in multivariable analysis if confounding is properly controlled. Furthermore, problems resulting from the automated forward and stepwise modeling with or without the presence of confounding are also addressed. To avoid these improper procedures and deficiencies, alternatives in performing multivariable analysis, including advantages and disadvantages of the BVS method and automated stepwise modeling, are reviewed and discussed.
The first aerosol indirect effect quantified through airborne remote sensing during VOCALS-REx

Abstract. The first aerosol indirect effect (1AIE) is investigated using a combination of in situ and remotely-sensed aircraft (NCAR C-130) observations acquired during VOCALS-REx over the southeast Pacific stratocumulus cloud regime. Satellite analyses have previously identified a high albedo susceptibitility to changes in cloud microphysics and aerosols over this region. The 1AIE was broken down into the product of two independently-estimated terms: the cloud aerosol interaction metric ACI τ = d ln τ / d ln N a | LWP , and the relative albedo (A) susceptibility S R - τ = d A /3 d ln τ | LWP , with τ and N a denoting retrieved cloud optical thickness and in situ aerosol concentration respectively and calculated for fixed intervals of liquid water path (LWP). ACI τ was estimated by combining in situ N a sampled below the cloud, with τ and LWP derived from, respectively, simultaneous upward-looking broadband irradiance and narrow field-of-view millimeter-wave radiometer measurements, collected at 1 Hz during four eight-hour daytime flights by the C-130 aircraft. ACI τ values were typically large, close to the physical upper limit (0.33), with a modest increase with LWP. The high ACI τ values slightly exceed values reported from many previous in situ airborne studies in pristine marine stratocumulus and reflect the imposition of a LWP constraint and simultaneity of aerosol and cloud measurements. S R - τ increased with LWP and τ , reached a maximum S R - τ (0.086) for LWP ( τ ) of 58 g m −2 (~14), and decreased slightly thereafter. The 1AIE thus increased with LWP and is comparable to a radiative forcing of −3.2– −3.8 W m −2 for a 10% increase in N a , exceeding previously-reported global-range values. The aircraft-derived values are consistent with satellite estimates derived from instantaneous, collocated Clouds and the Earth's Radiant Energy System (CERES) albedo and MOderate resolution Imaging Spectroradiometer (MODIS)-retrieved droplet number concentrations at 50 km resolution. The consistency of the airborne and satellite estimates, despite their independent approaches, differences in observational scales, and retrieval assumptions, is hypothesized to reflect the ideal remote sensing conditions for these homogeneous clouds. We recommend the southeast Pacific for regional model assessments of the first aerosol indirect effect on this basis. This airborne remotely-sensed approach towards quantifying 1AIE should in theory be more robust than in situ calculations because of increased sampling. However, although the technique does not explicitly depend on a remotely-derived cloud droplet number concentration ( N d ), the at-times unrealistically-high N d values suggest more emphasis on accurate airborne radiometric measurements is needed to refine this approach.
Revisiting the Pitch Controversy: Changes in Speaking Fundamental Frequency (SFF) After Management of Functional Dysphonia

Speaking fundamental frequency (SFF) and its perceptual correlate "habitual pitch" have been considered important and contentious parameters in voice assessment and treatment. In clinical circles, disagreement exists regarding the role of habitual pitch in the development, maintenance, and treatment of disordered voices. Despite these divergent opinions, few studies have objectively evaluated SFF changes associated with voice improvement after therapy. To determine whether consistent directional and magnitude changes in SFF occur after management, pretreatment and posttreatment audio recordings of 40 women with functional dysphonia were analyzed. All subjects were treated with manual circumlaryngeal therapy, a treatment approach that does not directly target pitch as a perceptual entity to be manipulated. Results indicated that, as a group, no significant change in mean SFF was observed after successful management. Although no consistent directional pattern was identified, 80% of the subjects experienced pitch changes greater than one semitone; this suggests that voice improvement is often accompanied by a shift in SFF. Clinical implications of the data are discussed.
Will the NP workforce grow in the future? New forecasts and implications for healthcare delivery.

Background:The nurse practitioner (NP) workforce has been a focus of considerable policy interest recently, particularly as the Patient Protection and Affordable Care Act may place additional demands on the healthcare professional workforce. The NP workforce has been growing rapidly in recent years,
Poisson-Nernst-Planck models of nonequilibrium ion electrodiffusion through a protegrin transmembrane pore.

Protegrin peptides are potent antimicrobial agents believed to act against a variety of pathogens by forming nonselective transmembrane pores in the bacterial cell membrane. We have employed 3D Poisson-Nernst-Planck (PNP) calculations to determine the steady-state ion conduction characteristics of such pores at applied voltages in the range of −100 to +100 mV in 0.1 M KCl bath solutions. We have tested a variety of pore structures extracted from molecular dynamics (MD) simulations based on an experimentally proposed octomeric pore structure. The computed single-channel conductance values were in the range of 290–680 pS. Better agreement with the experimental range of 40–360 pS was obtained using structures from the last 40 ns of the MD simulation, where conductance values range from 280 to 430 pS. We observed no significant variation of the conductance with applied voltage in any of the structures that we tested, suggesting that the voltage dependence observed experimentally is a result of voltage-dependent channel formation rather than an inherent feature of the open pore structure. We have found the pore to be highly selective for anions, with anionic to cationic current ratios (ICl−/IK+) on the order of 103. This is consistent with the highly cationic nature of the pore but surprisingly in disagreement with the experimental finding of only slight anionic selectivity. We have additionally tested the sensitivity of our PNP model to several parameters and found the ion diffusion coefficients to have a significant influence on conductance characteristics. The best agreement with experimental data was obtained using a diffusion coefficient for each ion set to 10% of the bulk literature value everywhere inside the channel, a scaling used by several other studies employing PNP calculations. Overall, this work presents a useful link between previous work focused on the structure of protegrin pores and experimental efforts aimed at investigating their conductance characteristics.
Electron microscopic studies of wallerian degeneration in rat optic nerves. I. The multipotential glia

The development of phagocytes has been studied with the electron and light microscopes in rat optic nerves undergoing Wallerian degeneration. The postoperative survival times ranged from five hours to 250 days. This paper focuses on cells that have been designated either as multipotential glia or as a third neuroglial cell type. Such cells increase markedly in number during the first several weeks of nerve fiber degeneration while the populations of astrocytes and oligodendrocytes remain relatively stable. During this early stage of degeneration, multipotential glial cells develop very irregular shapes and have many processes and complex folds that intermingle with the degenerating nerve fibers. These cells engulf myelin fragments and nerve fibers which become enclosed within vacuoles that show acid phosphatase reaction product in specimens prepared for cytochemistry. The debris containing vacuoles can therefore be considered as phagolysosomes. In addition, the multipotential glial cells show an increase in the number of lipid inclusions over that of cells in normal material. Eventually some multipotential glial cells accumulate large quantities of lipid inclusion and come to resemble the “Gitter” cells described in classical neuropathological studies. The numerical and cytological changes occurring within the multipotential glial population indicate that these cells are an important source of phagocytes in the type of lesion which we have studied. The breakdown of degenerating myelin by multipotential glial cells, the origin of these cells and their relationship to the microglial cells stained in light microscopic preparations are discussed in detail.
Nanoparticle-induced transition from positive to negative photochromism

Abstract We have designed and synthesized a photochromic spiropyran with a dithiolane appendage. The two sulfur atoms of the dithiolane ring encourage the adsorption of this compound on the surface of cadmium sulfide nanoparticles. The properties of the resulting photochrome–nanoparticle assemblies vary significantly with the experimental conditions selected for the preparation of the inorganic component. Nanoparticles prepared in the presence of tri-n-octylphosphine impose positive photochromism on the ligands. Instead, nanoparticles prepared in the presence of sodium dioctylsulfosuccinate impose negative photochromism on the ligand. This behavior is a consequence of the difference in the surface morphology of the two sets of nanoparticles. Indeed, emission spectra confirm the presence of surface defects on the nanoparticles exhibiting negative photochromism. Presumably, electrostatic interactions between these surface defects and the colored and zwitterionic isomer of the ligand are responsible for the transition from positive to negative photochromism. Thus, our studies demonstrate that the microscopic environment around a photochromic switch can regulate the relative stabilities of its colorless and colored states as well as their isomerization kinetics.
CFAR detection for multiple target situations

In the paper, three detectors are proposed and studied in the presence of interfering targets in the reference cells. In the weighted cell-averaging constant false-alarm rate (WCA-CFAR) detector the means generated by the leading and the lagging range cells are weighted in accordance with the level of the interference. Optimum weights that maintain CFAR are obtained while the probability of detection is maximised. The censored mean level detector (CMLD) is considered next, this requires exact knowledge of the number of interfering targets. The detection performance of the CMLD is studied for Swerling IV targets and compared to that with Swerling II targets. Then, the generalised censored mean-level detector (GCMLD) is proposed. The GCMLD does not require a priori knowledge of the number of interfering targets and achieves robust performance. The number of interfering targets is determined and their corresponding samples are then censored. Exact expressions for the probability of censoring the interfering targets and the overall probability of detection are derived. A comparison of the performance of the GCMLD with that of a recently proposed CFAR detector is also presented to demonstrate the robustness of the GCMLD.
Effect of Kainic Acid on Unit Discharge in CA1 Area of Hippocampal Slice of DBA and C57 Mice

Summary: Spontaneous unit discharges in stratum pyramidale of CA1 area of hippocampal slices from DBA and CS7 mice at different ages were recorded extracellularly. The average rate and amplitude of the spontaneous discharges from CA1 area of hippocampal slices bathed in artificial cerebrospinal fluid (aCSF) were not different between DBA and CS7 mice at either 3–4 or 5–6 weeks of age. Bath application of kainic acid (KA) in concentrations of 0·5–1·0 μM produced different responses in CA1 area from these two strains of mice. In DBA mice at age 3–4 weeks, when they are most susceptible to audiogenic seizures, KA perfusion induced high-frequency repetitive single spikes and bursts of multiple population spikes in CA1 area. Very high-frequency discharges (10-fold higher than most responses) were also observed in 20% of all slices. In audiogenic seizure resistant CS7 mice at age 3–4 weeks, KA perfusion at the same doses induced only the repetitive single spikes. The rate of spontaneous discharges was much lower than that in DBA mice. No burst of multiple population spikes nor very high-frequency responses were recorded in CS7 mice. At age 5–6 weeks, when both DBA and CS7 mice are resistant to audiogenic seizures, the rate of spontaneous discharges recorded from the CAI area during and after KA perfusion was lower than that at age 3–4 weeks, and there was no significant difference between DBA and CS7 mice. Pretreatment of hippocampal slices with AMPA/kainate receptor antagonist CNQX (10 pA4) markedly reduced the rate and amplitude of spontaneous discharges in CA1 area during and after KA perfusion, whereas competitive N-methyl-D-aspartate (NMDA) receptor antagonist D-APS had no effect. These results indicate that the responses in spontaneous discharges recorded extracellularly from stratum pyramidale in CA1 area of hippocampal slices to KA perfusion correlate with susceptibility to audiogenic seizures in DBA and CS7 mice.
On the phase transition to spacetime in string cosmology

Closed string models have recently been constructed in lower than their critical spacetime dimensionsD≤Dcr. An ideal gas of closed strings withD≥4 undergoes a phase transition at a universal point (Hagedorn temperature). We argue that solitonic configurations on the string world-sheet (vortices) drive the system into a high-temperature phase where the vacuum is dominated by vortex condensates. Flat spacetime is identified with the dipole low-temperature phase of vortex antivortex pairs. This is a “Kosterlitz-Thouless” transition on the string world-sheet. It is suggestive of a “stringy” realization of the inflationary universe paradigm.
Single strand DNA breaks in human leukocytes induced by ultrasound in vitro

Abstract Single strand breaks (SSBs) in the DNA of fresh human leukocytes were analyzed after in vitro exposure to ultrasound in an ice bath. The alkaline elution method was used to quantify the frequency of SSBs. Five different ultrasonic exposures were employed: (1) 53 mW/cm 2 spatial-peak temporal-average intensity (SPTA), 0.37:100 μs pulsed 6.2 MHz ultrasound presumably without cavitation, (2) 470 mW/cm 2 (SPTA) continuous 1.7 MHz ultrasound with gas-body activation, which is a form of cavitation lacking in chemical activity, (3) 10.8 W/cm 2 (SPTA), 3.0:100 μs pulsed 1.48 MHz ultrasound, presumably without cavitation, (4) 161 W/cm 2 (SPTA) continuous 1.45 MHz ultrasound with transient cavitation, and (5) 94 W/cm 2 (SPTA) continuous 8 MHz ultrasound presumably without cavitation. All of these exposures produced negative results, except (4), which yielded a significantly increased frequency of SSBs relative to sham exposed cells. For this condition, the SSB effect was comparable in magnitude to that of 1 Gy of 60 Co gamma-rays, and may have resulted from the chemical activity associated with transient cavitation. The SSBs were detected in cells which remained intact after exposure; however, it is uncertain if any of the ultrasonically-induced SSBs occurred in viable cells.
Production of fast and slow particles in nucleus-nucleus collisions at ultrarelativistic energies.

Multiplicity and angular distributions of shower, grey, and black particles produced in the interactions of $^{32}\mathrm{S}$ at 200A GeV, $^{16}\mathrm{O}$ at 200 and 60A GeV, and $^{4}\mathrm{He}$ at \ensuremath{\sim}140A GeV in emulsion are compared with the predictions of a Monte Carlo code which takes into account the internuclear cascading. The correlations between the various parameters belonging to the same or to the different kinds of particles are discussed. The data on shower and grey particles from all the beams are well described by the code. However, the black prong data show a significant departure from this model.
Beam squint in circularly polarised offset-reflector antennas

The beam-squint phenomenon, which is observed when offset portions of parabolic reflector surfaces are illuminated by circularly polarised primary feeds, can be a critical factor in the design of antennas employing frequency-reuse techniques. The letter describes the derivation of a very simple formula which can be employed to predict the magnitude of the beam-squint effect to an accuracy of better than 0.01 of the antenna halfpower beamwidth. Verification of the formula has been obtained using both computed and experimental data.
Drunk Driving, Distracted Driving, Moralism, and Public Health

Can we blend the moral passion of anti–drunk-driving activism with epidemiologically based strategies for saving lives on the roads? The history of efforts to prevent automobile crashes offers lessons on various approaches and their possible synergy.
Measurement of the electron affinity of thulium

The electron affinity of thulium has been measured using laser photodetachment electron spectroscopy. The electron affinity of $\mathrm{Tm}{(}^{2}{F}_{7/2})$ was determined to be $1.029\ifmmode\pm\else\textpm\fi{}0.022\mathrm{eV}.$ The data also show that ${\mathrm{Tm}}^{\mathrm{\ensuremath{-}}}$ has at least one bound excited state with a binding energy of $0.979\ifmmode\pm\else\textpm\fi{}0.017\mathrm{eV}$ relative to the ground state of the thulium atom. The present experimental measurements are compared to a recent calculation of the electronic structure of ${\mathrm{Tm}}^{\mathrm{\ensuremath{-}}}$ and a recent experimental investigation of ${\mathrm{Tm}}^{\mathrm{\ensuremath{-}}}.$
Active Vibration Control of Distributed Systems Using Delayed Resonator With Acceleration Feedback

The Delayed Resonator (DR) and Dual Frequency Fixed Delayed Resonator (DFFDR) are newly introduced control techniques for active vibration absorption. Both methods propose a delayed position feedback within the absorber section of the structure to impart ideal resonance features to the absorber. When installed on an oscillating primary body, they form notch filters at their resonance frequencies attenuating the response of the primary structure. The DR absorber is shown to be real-time tunable to time varying disturbance frequencies. In this article, a number of new issues are considered. First, the basic theory is modified for acceleration feedback instead of position, which was originally proposed for the DR methodology. Second, the new absorption methods are implemented on distributed parameter structures which are under high frequency excitation (around 1 KHz). Stability of the combined structure is studied on a reduced order multi-degree-of-freedom primary structure together with the DR absorber. Experimental tests are conducted on a steel beam to verify the analytical findings. Piezoelectric actuators are used both to generate harmonic disturbances and to implement the control. The correspondence observed between the theoretical and experimental results is encouraging. The efficiency of the DR and DFFDR absorption techniques is demonstrated.
Collection, Removal, and Quantification of Eggs Produced by Rosy Red Fathead Minnows in Outdoor Pools

Abstract Eggs produced by rosy red fathead minnows Pimephales promelas held at four densities in 12 outdoor pools were collected and removed from substrate and had their numbers estimated. Adult fish were stocked at a sex ratio of 4:1 (females: males) and at densities of 5.1, 15.3, 25.4, or 35.6 fish/m2. Sodium sulfite (1.5–2.0%) was used to detach fathead minnow eggs from the spawning substrate. Egg numbers were estimated volumetrically based on an average (±SD) of 578 ± 34 eggs per milliliter. Mean daily egg numbers generally increased with fish density, and production ranged from 2,587 ± 2,999 to 9,595 ± 2,423 eggs/kg of broodfish. Averaging all treatments together for the 16-d period, over 6,000 eggs/d were collected per kilogram of broodfish. Based on this estimate, 500 kg of broodfish in a 1-ha pond would produce an average of 3 million eggs each day. Assuming an 80% hatching rate, this number of eggs would result in enough fry to stock a 0.5–1.0-ha pond. The results imply that an intensive producti...
Single spike solutions for strings on S-2 and S-3

We study solutions for rigidly rotating strings on a two-sphere. Among them we find two limiting cases that have a particular interest, one is the already known giant magnon and the other we call the single spike solution. The limiting behavior of this last solution is a string infinitely wrapped around the equator. It differs from that solution by the existence of a single spike of height 0 that points toward the north pole. We study its properties and compute its energy E and angular momentum J as a function of 0. We further generalize the solution by adding one angular momentum to obtain a solution on S 3 . We find a spin chain interpretation of these results in terms of free fermions and the Hubbard model but the exact relation with the same models derived from the field theory is not clear.
Notch Ligand Presenting Acellular 3D Microenvironments for ex vivo Human Hematopoietic Stem‐Cell Culture made by Layer‐By‐Layer Assembly

Development of in vitro human hematopoietic stem cell (HSC) niches that can recapitulate the bone marrow and thymus function is imperative for understanding the fundamental biology of human hematopoiesis. Currently most information of HSC self-renewal and lineage commitment has been primarily derived from murine studies where a substantial knowledge gap in humans still exists. Such established functional tissue analogues can also greatly serve as a valuable tool to identify specific signaling factors and their precise roles in hematopoiesis by systematically manipulating major experimental parameters. The thymus is a specialized organ providing unique environments for the development of T-lymphocytes from bone-marrow-derived HSCs. Although the precise nature of the thymic environment inducing T-cell differentiation remains uncertain, it has been identified that stromal cells and 3D microarchitecture play a critical role from numerous studies of ex vivo HSC cultures. For example, thymic stromal cells activate various cell-signaling processes through secreting growth factors and expressing membrane-bound ligands. Their 3D organization creates a distinctive intrathymic 3D microarchitecture that coordinates the aforementioned signaling milieus. Thymocytes passing through the interstices of the 3D network of thymic stroma undergo extensive physical contacts with stromal cells, which is the main mechanism to promote T-cell differentiation and maturation. Due to such complexity, until recently the only reliable in vitro culture model for successful T-cell differentiation was the fetal thymus organ culture (FTOC), which is composed of a 3D reaggregated dissection of fetal thymic tissues.
Intraductal assessment to determine response to chemopreventive interventions

One of the difficulties that translational scientists encounter in evaluating agents to prevent breast cancer is the assessment of efficacy in real time. Classically, one evaluates chemopreventive efficacy based on whether the intervention leads to a lower number of cancers in the treatment than in the control group(s), but these studies require a large sample size and/or take years to complete in order to obtain a sufficient number of events for statistical comparison. We have used intraductal evaluation of breast nipple aspirate fluid (NAF) and mammary ductoscopy (MD) to assess response to both pharmacologic and nutritional chemopreventive interventions. Specifically, we have measured expression of specific proteins in NAF and changes in DNA methylation in MD specimens both before after the interventions. I will review our findings using these strategies, and discuss both the strengths and limitations of the approach.
Affine invariant shape representation and recognition using Gaussian kernels and multi-dimensional indexing

This paper presents a new approach for object recognition using affine-invariant recognition of image patches that correspond to object surfaces that are roughly planar. A novel set of affine-invariant spectral signatures (AISSs) are used to recognize each surface separately invariant to its 3D pose. These local spectral signatures are extracted by convolving the image with a novel configuration of Gaussian kernels. The spectral signature of each image patch is then matched against a set of iconic models using multi-dimensional indexing (MDI) in the frequency domain. Affine-invariance of the signatures is achieved by a new configuration of Gaussian kernels with modulation in two orthogonal axes. The proposed configuration of kernels is Cartesian with varying aspect ratios in two orthogonal directions. The kernels are organized in subsets where each subset has a distinct orientation. Each subset spans the entire frequency domain and provides invariance to slant, scale and limited translation. The complete set of orientations is utilized to achieve invariance to rotation and tilt. Hence, the proposed set of kernels achieve complete affine-invariance.
Learning the viewpoint manifold for action recognition

Researchers are increasingly interested in providing video-based, view-invariant action recognition for human motion. Addressing this problem will lead to more accurate modeling and analysis of the type of unconstrained video commonly collected in the areas of athletics and medicine. Previous viewpoint-invariant methods use multiple cameras in both the training and testing phases of action recognition or require storing many examples of a single action from multiple viewpoints. In this paper, we present a framework for learning a compact representation of primitive actions (e.g., walk, punch, kick, sit) that can be used for video obtained from a single camera for simultaneous action recognition and viewpoint estimation. Using our method, which models the low-dimensional structure of these actions relative to viewpoint, we show recognition rates on a publicly available data set previously only achieved using multiple simultaneous views.
Amino sugar phosphate levels in Giardia change during cyst wall formation.

The parasite Giardia intestinalis exists as a trophozoite (vegetative) that infects the human small intestine, and a cyst (infective) that is shed in host faeces. Cyst viability in the environment depends upon a protective cyst wall, which consists of proteins and a unique β(1-3) GalNAc homopolymer. UDP-GalNAc, the precursor for this polysaccharide, is synthesized from glucose by an enzyme pathway that involves amino sugar phosphate intermediates. Using a novel method of microanalysis by capillary electrophoresis, the levels of amino sugar phosphate intermediates in trophozoites before encystment, during a period of active encystment and after the peak of encystment were measured. These levels were used to deduce metabolic control of amino sugar phosphates associated with encystment. Levels of amino sugar phosphate intermediates increased during encystment, and then decreased to nearly non-encysting levels. The most pronounced increase was in glucosamine 6-phosphate, which is the first substrate unique in this pathway, and which is the positive effector for the pathway's putative rate-controlling enzyme, UDP-GlcNAc pyrophosphorylase. Moreover, more UDP-GalNAc than UDP-GlcNAc, its direct precursor, was detected at 24 h. It is postulated that the enhanced UDP-GalNAc is a result of enhanced synthesis of UDP-GlcNAc by the pyrophosphorylase, and its preferential conversion to UDP-GalNAc. These results suggest that kinetics of amino sugar phosphate synthesis in encysting Giardia favours the direction that supports cyst wall synthesis. The enzymes involved in synthesis of UDP-GalNAc and its conversion to cyst wall might be potential targets for therapeutic inhibitors of Giardia infection.