cssi/SciSciGPT-SciSciNet huggingface dataset:
Multisite Phosphorylation Disrupts Arginine-Glutamate Salt Bridge Networks Required for Binding of Cytoplasmic Linker-associated Protein 2 (CLASP2) to End-binding Protein 1 (EB1)

A group of diverse proteins reversibly binds to growing microtubule plus ends through interactions with end-binding proteins (EBs). These +TIPs control microtubule dynamics and microtubule interactions with other intracellular structures. Here, we use cytoplasmic linker-associated protein 2 (CLASP2) binding to EB1 to determine how multisite phosphorylation regulates interactions with EB1. The central, intrinsically disordered region of vertebrate CLASP proteins contains two SXIP EB1 binding motifs that are required for EB1-mediated plus-end-tracking in vitro. In cells, both EB1 binding motifs can be functional, but most of the binding free energy results from nearby electrostatic interactions. By employing molecular dynamics simulations of the EB1 interaction with a minimal CLASP2 plus-end-tracking module, we find that conserved arginine residues in CLASP2 form extensive hydrogen-bond networks with glutamate residues predominantly in the unstructured, acidic C-terminal tail of EB1. Multisite phosphorylation of glycogen synthase kinase 3 (GSK3) sites near the EB1 binding motifs disrupts this electrostatic “molecular Velcro.” Molecular dynamics simulations and 31P NMR spectroscopy indicate that phosphorylated serines participate in intramolecular interactions with and sequester arginine residues required for EB1 binding. Multisite phosphorylation of these GSK3 motifs requires priming phosphorylation by interphase or mitotic cyclin-dependent kinases (CDKs), and we find that CDK- and GSK3-dependent phosphorylation completely disrupts CLASP2 microtubule plus-end-tracking in mitosis.
Quantification of pausing on fixed-ratio schedules of reinforcement

Rat and pigeon data that had been collected in three separate laboratories were examined with reference to the effects on fixed-ratio behavior of either delaying the delivery of a scheduled reinforcer and/or varying the size of the ratio requirement. All such effects were reflected as changes in the duration of the interval (the preratio pause) that intervened between delivery of a reinforcer and commencement of responding for the next one. Although there was considerable variability in the absolute values obtained for the functions, in all cases, and for each individual subject, the relationship between these independent variables and durations of the preratio pause was well described by a power function. This finding is consonant with a previously offered suggestion that power functions provide a useful measurement of response strength for latency-type data.
A passively modelocked laser with tunable pulse-repetition frequency in a semiconductor optical amplifier

We present experimental demonstration of passively modelocked laser with pulse-repetition frequency tunable using semiconductor optical amplifier as the gain medium. The principle of operation is based on normal mode competition of a coupled cavity comprised of a quantum cavity and an optical cavity represented by a semiconductor gain medium, and a high-birefringence fiber in line with a Faraday mirror respectively. Experimental results are presented for pulse-repetition frequency shows stable tunability over a frequency decade of 93MHz and 1400MHz.
TBX5 transcription factor regulates cell proliferation during cardiogenesis.

Abstract Mutations in human TBX5, a member of the T-box transcription factor gene family, cause congenital cardiac septation defects and isomerism in autosomal dominant Holt–Oram syndrome. To determine the cellular function of TBX5 in cardiogenesis, we overexpressed wild-type and mutant human TBX5 isoforms in vitro and in vivo. TBX5 inhibited cell proliferation of D17 canine osteosarcoma cells and MEQC quail cardiomyocyte-like cells in vitro. Mutagenesis of the 5′ end of the T-box but not the 3′ end of the T-box abolished this effect. Overexpression of TBX5 in embryonic chick hearts showed that TBX5 inhibits myocardial growth and trabeculation. TBX5 effects in vivo were abolished by Gly80Arg missense mutation of the 5′ end of the T-box. PCNA analysis in transgenic chick hearts revealed that TBX5 overexpression does suppress embryonic cardiomyocyte proliferation in vivo. Inhibitory effects of TBX5 on cardiomyocyte proliferation include a noncell autonomous process in vitro and in vivo. TBX5 inhibited proliferation of both nontransgenic cells cocultured with transgenic cells in vitro and nontransgenic cardiomyocytes in transgenic chick hearts with mosaic expression of TBX5 in vivo. Immunohistochemical studies of human embryonic tissues, including hearts, also demonstrated that TBX5 expression is inversely related to cellular proliferation. We propose that TBX5 can act as a cellular arrest signal during vertebrate cardiogenesis and thereby participate in modulation of cardiac growth and development.
The influence of gaseous ozone and ozonated water on microbial flora and degradation of aflatoxin B1 in dried figs

In this study, the effectiveness of gaseous ozone and ozonated water on microbial flora and aflatoxin B(1) content of dried figs were investigated. After dried figs were exposed to13.8mgL(-1) ozone gas and 1.7mgL(-1) ozonated water for 7.5, 15 and 30min, variation of aerobic mesophilic bacteria (AMB), E. coli, coliform, yeast and mold counts were determined. Before and after ozone treatments molds on dried figs were also isolated and identified. In both ozone treatments, AMB was not exactly inactivated whereas E. coli was completely destroyed at 7.5min. Coliform, and yeast were also destroyed at 7.5 and 15min in ozonated water, respectively. Ozone applications at 15min were sufficient for inactivation of all molds. Aspergillus flavus and Aspergillus parasiticus which cause aflatoxin formation were isolated from dried figs. Artificially contaminated with aflatoxin B(1) samples were also treated with gaseous ozone and ozonated water for 30, 60 and 180min, respectively. In both of treatments, degradation of aflatoxin B(1) was increased due to increasing of ozonation time. Results indicated that gaseous ozone was more effective than ozonated water for reduction of aflatoxin B(1), whereas ozonated water was affected for decreasing microbial counts.
Partial Equine Lung Resection Using a Stapling Instrument

Four horses (aged 1 to 18 years) with no apparent respiratory or cardiovascular abnormalities underwent thoracotomy and partial resection of a cranial lung lobe. A stapling instrument was used. Pulmonary function testing prior to and 30 days following surgery showed no significant change in inspiratory or expiratory resistance, compliance, or work of breathing. Postoperative complications consisted of a mild pneumothorax in all horses and localized incisional infection in two horses. All horses displayed a temporary decrease in forward motion of the forelimb on the operated side. Postmortem examination was performed 30 days after surgery; pleural thickening and adhesions between the lung and thoracotomy site were found. The excisionai margin of each cranial lobe was straight with slight puckering due to multiple surgical wire staples. Adjacent tissue collapse and compression were confined to an area no greater than 1 cm from the staples. Beyond this compression, the remaining lung at the surgical site was histologically normal. Subsequently, one horse suffering from recurrent episodes of clinical signs attributed to pleuropneumonia underwent left thoracotomy and partial lung resection followed by a right thoracotomy 48 days later. The horse's condition improved postoperatively, and he was able to undergo normal conditioning and racing.
Workplace surveillance for carpal tunnel syndrome: A comparison of methods.

A variety of screening procedures for carpal tunnel syndrome (CTS) were applied among workers in a manufacturing plant, and results were compared. The test procedures included a symptom survey, physical examination, limited electrodiagnostic testing at the wrists, quantitative vibratory threshold testing, 2-point discrimination, palmar pinch grip, and hand grip strength testing. When electrodiagnostic testing alone was used as "gold standard," the sensitivity and positive predictive value (PPV) of physical examination findings and quantitative test procedures were no better than, and usually worse than, the results on the symptom survey alone. Variation of the constellation of symptoms (i.e., numbness, tingling, pain or burning) and the anatomic distribution of reported symptoms (i.e., fingers, hand, wrist, or forearm) for inclusion in the screening symptom definition of CTS yielded modest changes in the sensitivity and PPV of the symptom survey. However, addition of the requirement for nocturnal symptoms as part of the screening symptom definition for CTS resulted in substantially higher PPV with only slight reduction in sensitivity. These results suggest that, in the absence of electrodiagnostic testing, the simplest test, and the procedure with the highest sensitivity and PPV for CTS is a symptom survey alone. Quantitative test procedures (vibrometry, pinch grip strength, hand grip strength) and physical examination for findings consistent with CTS (e.g., Phalen's test, Tinel's test, thenar muscle wasting, 2-point discrimination) appear to contribute little, if any, additional information when screening subjects in the work setting.
Life History of Cambarus Robustus Girard in the Eramosa-Speed River System of Southwestern Ontario, Canada (Decapoda, Astacidea)

La longevite moyenne de Cambarus robustus est de 3 ans, avec tres peu d'individus survivant une annee de plus. Les animaux se reproduisent a la fin du troisieme ete. Les mâles de la forme I ont une longueur de carapace moyenne de 30,6 mm, S.D. 3,23 mm, et mesurent de 23,4 a 41,9 mm. Les femelles ovigeres apparaissent a la fin de juin et en juillet. Les femelles a maturite ont une longueur de carapace moyenne de 29,7 mm, S.D. 1,42 mm, et mesurent de 24,3 a 34,3 mm. Le nombre moyen des oeufs est de 61,1 (S.D. 26,8). La taille, l'âge et la fecondite de C. robustus dans le systeme de rivieres Eramosa-Speed sont bien inferieurs a ce qui a ete observe dans la region des lacs Kawartha (Hamr & Berrill, 1985).
Iron Aerogel and Xerogel Catalysts for Fischer-Tropsch Synthesis of Diesel Fuel

Iron aerogels, potassium-doped iron aerogels, and potassium-doped iron xerogels have been synthesized and characterized and their catalytic activity in the Fischer−Tropsch (F-T) reaction has been studied. Iron aerogels and xerogels were synthesized by polycondensation of an ethanolic solution of iron(III) chloride hexahydrate with propylene oxide which acts as a proton scavenger for the initiation of hydrolysis and polycondensation. Potassium was incorporated in the iron aerogel and iron xerogel by adding aqueous K2CO3 to the ethanolic solutions of the Fe(III) precursor prior to addition of propylene oxide. Fischer−Tropsch activities of the catalysts were tested in a fixed bed reactor at a pressure of 100 psi with a H2:CO ratio of 2:1. Iron aerogels were found to be active for F-T synthesis, and their F-T activities increased on addition of a K containing promoter. Mossbauer spectroscopic data are consistent with an open, nonrigid iron(III) aerogel structure progressing to an iron carbide/metallic iron ca...
Multifragment emission in 36Ar+197Au and 129Xe+197Au collisions. Percolation model

Abstract Relative abundances of intermediate mass fragments and light particles measured for 36 Ar+ 197 Au collisions at E A = 50, 80 and 110 MeV lie within the range of percolation model predictions, but for 129 Xe+ 197 Au collisions at E A = 50 MeV , the percolation model predicts too small admixtures of intermediate mass fragments among the emitted charged particles.
Enhanced, simplified expression of perdeuterated hemoglobin for NMR structure and dynamics

Abstract An advanced protocol is provided to adapt cells for enhanced proliferation in and expression from deuterated minimal media. For large proteins (>20–30 kDa), deuteration levels >90% are essential for NMR characterization of structure and dynamics. In addition, the low sensitivity of NMR demands can be achieved without major sacrifice to yield. We applied the approach to human adult hemoglobin (Hb A), a 64 kDa, tetrameric protein that requires significant post-expression processing. This aspect accentuates the need for high yield. Using specially adapted JM109(DE3) Escherichia coli , we developed a shake-flask approach to express >90% deuterated NMR samples. Typical yields were 2.5-fold higher than obtained from cells adapted by more-traditional methods, while deuteration levels were increased by 17%. Ultimately, a 200 mL culture was sufficient to obtain ( 2 H, 15 N)-labeled Hb A sufficient for a 200 μM, 400 μL NMR sample. This avoids need for additional equipment for fermentation, which was used in previous protocols to express Hb A. It also allows a much smaller culture volume than often required by such equipment, for corresponding linear reductions in the cost of labeled starting materials. We tested the adaptation protocol with both JM109 and JM109(DE3) E. coli , and with pre- and post-transformation with the Hb A expression plasmid (pHE7). The (DE3) strain consistently outperformed its parent strain in response to adaptation, with the latter failing to survive adaptation in multiple trials. In addition, pre-transformed cells were consistently more receptive to adaptation. Finally, we also detail updated protocols to isolate Hb A in its functional form.
Image Reconstruction from Incomplete Projection Data: Iterative Reconstruction-Reprojection Techniques

This paper addresses the task of image reconstruction from an incomplete set of projection data. Several methods which first estimate the missing data and then utilize standard reconstruction algorithms to obtain an image are investigated. Results from simulations are presented which illustrate the difficulty in comparing algorithms objectively, particularly when a simple test phantom is chosen. The incorporation of a priori information into the algorithm, an approach which has previously been discussed in the literature, is shown to produce faster convergence.
Exon skipping gives rise to alternatively spliced forms of the estrogen receptor in breast tumor cells

We have previously described three messenger RNA variants coding for the human estrogen receptor (ER) [1]. These variants were identified using the polymerase chain reaction to perform directed cloning of ER cDNAs synthesized from polyadenylated RNA extracted from the human breast cancer cell line T47D. Each of the variants is characterized by the precise deletion of a single exon within the protein coding region of this message and was presumably derived by inaccurate or promiscuous splicing of primary estrogen receptor transcripts. We report here the results of RNAse protection experiments which independently confirm the existence of these splicing variants in T47D cells. Similar analysis of RNA from MCF-7 cells also revealed the presence of variant ER transcripts, suggesting that they may be a common finding in tumor cell lines which express the estrogen receptor. However, attempts to identify splicing variants in a number of nominally ER-negative cell lines using either RNAse protection or PCR amplification were without success.
The effect of a colouring matter separated from hibiscus sabdariffa on mycobacterium tuberculosis as compared to that of its watery extract

Twenty milliliters of a 15% watery extract, and 3 ml of a 10% solution ofHibiscus colouring matter, prevented the growth ofMycobacterium tuberculosis when added to flasks containing 150 ml and 50 ml respectively of glycerine broth. Ten milliliters of a 20%Hibiscus watery extract, and 3 ml of a 10% solution ofHibiscus colouring matter, inhibited the appearance of tubercle nodules when injected simultaneously with tubercle bacilli.
Issues Surrounding Polypharmacy

Polypharmacy is being practice in greater force today than it was 20 years ago. There are many reasons for this practice, including (1) the availability of a greater number of newer medications to treat a wider range of conditions, (2) aging population that is notorious for taking multiple medications, and (3) practice guidelines that advocate for the use of more than one drug to treat recalcitrant conditions. A closer look at the issues surrounding the practice of polypharmacy is discussed here.
Introduction: The Many Faces of Aging: Challenges for the Future

In coming decades, the United States will see a major demographic shift as the largest birth cohort in our history approaches its older years; by the year 2030, it has been projected that approximately one-third of the population will be aged 65 or older. Yet the national debate on how we plan to accommodate our aging society is in considerable turmoil. This symposium offers the insights of several leaders in the fields of social work and aging regarding the profound economic, political, and moral implications of the projected changes in society. While medical and technological advances promise greater independence and higher quality of life for some, there is a disturbing trend of economic inequality for future elders. It is expected that the "baby boom" generation will not only bring about major policy changes, but will redefine aging and the search for meaning in what Charles Fahey has termed the "third age." It is certain that the societal values we hold and our commitment to the well-being of our older population today will have a profound impact on what the future holds for old and young alike.
Optical Double Negative Metamaterial at 813 nm

A negative index metamaterial demonstrating n=-1.0+0.8i with both negative effective permittivity and permeability at 813nm of linearly polarized light is fabricated. It also exhibits a negative refractive index (n= -0.7+1.3i) at 772nm for orthogonal polarization.
Taste aversion disruption by drug pretreatment: Dissociative and drug-specific effects

Abstract Disruption of taste aversion learning following the administration of the same drug prior to and during conditioning (intra-agent disruption) was shown to be greater than disruption following the administration of one drug prior to conditioning and another during conditioning (inter-agent disruption). Comparable dosages of ethanol and lithium chloride served as unconditioned stimuli. Inter-agent disruptions are attributed to a dissociation of conditioned and unconditioned stimuli, while intra-agent disruptions are attributed to both a dissociative effect and drug-specific effects. Intra-agent disruptions are measure of tolerance, suggesting tolerance constitutes at least a portion of the drug-specific effects.
Ethnic Relations in Southeastern Mexico1

ALTHOUGH Spanish colonization of the highlands of Chiapas dates from the early 16th century, the region still constitutes one of the major Indian enclaves within Mexico. The state of Chiapas in southeastern Mexico is located southwest of the Yucatan peninsula and west of Guatemala. The town of San Cristobal de Las Casas, founded in 1528, is the major center of Spanish culture in the highlands of the state. Located at 7000 feet of elevation along the PanAmerican Highway, San Cristobal had a population of 17,473 at the time of the 1950 Census (Vivo Escoto 1959:217). The climate is tropical as far as the alternation of rainy and dry seasons is concerned, but quite cool due to the elevation. Town dwellers are almost all hispanicized to the extent of speaking only Spanish and dressing much as in the rest of Mexico. The inhabitants of San Cristobal call themselves ladinos2 Genetically they range from pure or almost pure Spanish stock to pure American Indian stock. While the upper class (called clase alta, gente bien, la crema, or los blancos) is mostly White, the middle class (clase media) is mostly light mestizo (mixed blood), and the lower class (gente humilde) is in majority dark mestizo or Indian-looking. Though an occasional lower class person is Caucasoid-looking, and some upper class persons are somewhat mestizoized, the genetic continuum overlaps greatly with the social class continuum. This is not to say, however, that genetic characteristics are the primary criteria of social status in San Cristobal. While the town is rigidly stratified, and its inhabitants strongly class-conscious, wealth (as indexed by dress, landownership, type of house, number of servants, etc.), and education (as shown by literacy, correctness of speech, university degree, manners, etc.) are more important than physical appearance in determining one's status. An educated person of Indian appearance may be the object of mild ostracism from the old upper class families but is accepted among the middle class. Conversely, a white skin will not exempt a poor illiterate person from membership in the lower class. The social class system is reflected in the ecology of San Cristobal: the social status of houses is inversely proportional to the distance from the central town square. As one walks from the center of the town to its outskirts, houses change from bricks or stones and tile roofs, to whitewashed adobe and tiles, to raw adobe and tiles, to straw-thatched huts with lattice walls. Street condition deteriorates from concrete, to irregular cobblestones, to unimproved mud holes, with the exception of one main arterial street that crosses the city from east to west. The arrangement of the San Cristobal cemetery, located
Scanning reflection electron microscopy and associated techniques for surface studies

Abstract A variety of signals generated by electron beam/specimen interactions has been utilized to give structural, topographical and chemical information about the sample of interest. Each technique has its unique advantages and disadvantages, but the combination of different techniques can give more and more reliable results. Monotomic surface steps and surface dislocations have been imaged with high contrast in scanning reflection electron microscopy (SREM) images. With the use of dynamic focusing compensation SREM images can be kept in focus over a large field of view. Surface step structures have been examined by collecting secondary electrons with an image resolution approaching the probe size used in dedicated scanning transmission electron microscopy (STEM) instruments. Auger electrons, carrying chemical information, have been used to form images of surface steps and small particles deposited on oxide substrates. Nanometer-resolution Auger electron images have been obtained in our UHV STEM instrument and small metal clusters containing as few as 15 atoms have been detected in Auger peak images. The combination of various imaging, diffraction and analytical techniques has proved very powerful for characterizing surface structures with high spatial resolution and chemical sensitivity.
The safety and effectiveness of a curved needle for vertebral augmentation: comparison with traditional techniques.

Purpose To evaluate the safety and effectiveness of a curved needle compared with traditional (noncurved needle) techniques in a large single-center experience. Materials and Methods This study was a retrospective analysis of 243 consecutive vertebral augmentation procedures over a 17-month period. Curved needle procedures were compared with noncurved needle procedures for baseline clinical variables, complication rate, pain relief, and improvement in disability. Procedure duration and fluoroscopy time were compared between the two cohorts. Results Between curved needle and noncurved needle procedures, there were no statistically significant differences in the baseline clinical variables, fracture location, and fracture etiology. No complications were noted in either group. In both groups, there was a median improvement in the visual analog scale (VAS) score of 2.0 points ( P = .62). More than 90% of procedures in both groups resulted in some pain improvement ( P = .78). For both groups, the median improvement in disability on the Roland Morris Disability Questionnaire (RMDQ) was 4.0 points ( P = .69). Approximately 70% of procedures in both groups resulted in improvement in disability ( P = 1.00). In single-level cases, there were shorter procedure times (51.8 min ± 2.7 vs 62.8 min ± 2.2, P = .002) and shorter fluoroscopy times ( P = .31) for curved needle procedures. Conclusions The curved needle is as safe and effective as traditional vertebral augmentation techniques in treating the pain and disability related to vertebral compression fractures. Additionally, the curved needle is associated with shorter procedure duration and reduced fluoroscopy time.
Intratidal Dynamics of Fronts and Lateral Circulation at the Shoal–Channel Interface in a Partially Stratified Estuary

AbstractIn partially stratified shoal–channel estuaries, variations in bathymetry at the shoal–channel interface generate horizontal shears and density gradients, and foam lines characteristic of convergence fronts are frequently observed. This study is based on transect data collected every 30 min across the shoal–channel interface in south San Francisco Bay to analyze the dynamics of the transverse circulation and convergence fronts at this interface throughout a tidal cycle. During the ebb, a lateral density gradient develops as a result of the competition between differential advection of the longitudinal salinity gradient; lateral variations in vertical mixing; and nonlinear advection terms, which are strongest when convergence fronts develop early and late in the ebb. The lateral circulation over the slope is characterized by a large intratidal variability, reversing three times during the ebb. This variability is driven by a balance dominated by inertia and lateral baroclinic pressure gradient duri...
Topology, Dimerization, and Stability of the Single-Span Membrane Protein CadC

Under acid stress, Escherichia coli induce expression of CadA (lysine decarboxylase) and CadB (lysine/cadaverine antiporter) in a lysine-rich environment. The ToxR-like transcriptional activator CadC controls expression of the cadBA operon. Using a novel signal peptidase I (SPase I) cleavage assay, we show that CadC is a type II single-span membrane protein (S-SMP) with a cytoplasmic DNA-binding domain and a periplasmic sensor domain. We further show that, as long assumed, dimerization of the sensor domain is required for activating the cadBA operon. We prove this using a chimera in which the periplasmic domain of RodZ—a type II membrane protein involved in the maintenance of the rod shape of E. coli—replaces the CadC sensor domain. Because the RodZ periplasmic domain cannot dimerize, the chimera cannot activate the operon. However, replacement of the transmembrane (TM) domain of the chimera with the glycophorin A TM domain causes intramembrane dimerization and consequently operon activation. Using a low-expression protocol that eliminates extraneous TM helix dimerization signals arising from protein over-expression, we enhanced dramatically the dynamic range of the β-galactosidase assay for cadBA activation. Consequently, the strength of the intramembrane dimerization of the glycophorin A domain could be compared quantitatively with the strength of the much stronger periplasmic dimerization of CadC. For the signal peptidase assay, we inserted an SPase I cleavage site (AAA or AQA) at the periplasmic end of the TM helix. Cleavage occurred with high efficiency for all TM and periplasmic domains tested, thus eliminating the need for the cumbersome spheroplast-proteinase K method for topology determinations.
Impact of Initial Conditions, Rainfall Assimilation, and Cumulus Parameterization on Simulations of Hurricane Florence (1988)

Abstract Numerical simulations were performed with the Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model Version 5 (MM5) to study the impact of initial conditions, satellite-derived rain assimilation, and cumulus parameterization on Hurricane Florence (1988). A few modifications were made to the J. Manobianco et al. (MKKN) rain assimilation scheme, which was developed originally for midlatitude weather systems, to successfully simulate organized tropical weather systems such as Florence. These changes consist of replacing latent heating scaling with convective rainfall in the Kuo–Anthes scheme in areas where both the model-predicted and satellite-derived rainfall coincide, and specifying a normalized parabolic heating profile in deep convective regions where there is satellite rain but no model rain. Restoration of the original Kuo–Anthes heating distribution function in lieu of the fixed heating profile specified in the MM5 model is another change implemented in the K...
Issues in the Use of I. A. Richards' Tenor-Vehicle Model of Metaphor.

Since its introduction in 1936, I. A. Richards’ tenor‐vehicle model of metaphor has seen extended use in communication scholarship. The definition of the model's terms and the application of its constructs have varied widely over time and among authors. Together with ambiguities in Richards’ original articulation of the model, inconsistencies in its use and lack of critique combine to draw into question the model's coherence. This essay reviews Richards’ conception of the model and subsequent treatment of its components, evaluates various patterns of appropriation, and makes recommendations regarding future usage.
A failed attempt to autoshape leverpressing in horses

In this paper, we describe a study in which we attempted to autoshape three horses to make a leverpress response. This study was motivated by observations made during earlier studies (Dougherty & Lewis, 1991b, 1992) in which we observed horses directing consummatory behaviors toward stimuli signaling the availability of reinforcers. The procedure was similar to that of other autoshaping procedures. Horses received forward conditioning trials in which stimuli (an illuminated panel and a retractable response lever) were periodically presented together for 10 sec and followed by a grain reinforcer. Each horse’s stall served as an experimental chamber. A response panel was positioned in the stall’s doorway, and a computer located nearby controlled and monitored experimental events. Each day, for 14 days, 100 stimulus-reinforcer pairings were presented. Despite 1,400 stimuli-reinforcer presentations, none of the horses were autoshaped. A few possible reasons for these results are discussed.
Diversifying secondary school curricula in developing countries: An implementation history and some policy options

Abstract This paper describes the history of the diversified curriculum debate. The first section briefly refers to the precedents for such discussions during the colonial era. A second section describes the institutional environment behind the beginning of bilateral and multilateral assistance to diversified curricula in 1960. The third section summarizes the changes in thinking about diversified curricula which have occurred in the World Bank over the last 20 years. This third section, itself, is divided into three subsections: (i) the original World Bank rationales for diversified education (1960–1970); (ii) the implementation history (1970–1980); and (iii) post-1980 strategies, including financing the research whose results are discussed at this meeting. The paper concludes with a fourth section which refers to the options on diversified education ahead.
Surgical and clinical efficacy of sacroiliac joint fusion: a systematic review of the literature.

OBJECT The sacroiliac joint (SIJ) and surgical intervention for treating SIJ pain or dysfunction has been a topic of much debate in recent years. There has been a resurgence in the implication of this joint as the pain generator for many patients experiencing low-back pain, and new surgical methods are gaining popularity within both the orthopedic and neurosurgical fields. There is no universally accepted gold standard for diagnosing or surgically treating SIJ pain. The authors systematically reviewed studies on SIJ fusion in the neurosurgical and orthopedic literature to investigate whether sufficient evidence exists to support its use. METHODS A literature search was performed using MEDLINE, Google Scholar, and OvidSP–Wolters Kluwer Health for all articles regarding SIJ fusion published from 2000 to 2014. Original, peer-reviewed, prospective or retrospective scientific papers with at least 2 patients were included in the study. Exclusion criteria included follow-up shorter than 1-year, nonsurgical treat...
Self-focusing in SF 6

We calculate the susceptibility responsible for self-focusing in SF(6) in two parts, the v(3)-ladder contribution and the quasi-continuum contribution. Our v(3)-ladder vibrational model is a classical triply degenerate anharmonic oscillator in the Cartesian basis with the anharmonicity parameters chosen to be consistent with the latest spectroscopic analysis of the 3v(3)-overtone spectrum. The rotational structure is represented by a distribution of these oscillators in which the distribution is chosen to correspond to the spectrum of the v(3) fundamental. Using our previously published model, we find that the quasi-continuum contribution is much smaller than the v(3)-ladder contribution to the susceptibility and always decreases with increasing laser energy. We find that the v(3) ladder is entirely responsible for self-focusing in SF(6) . The susceptibility curves show qualitative agreement with the 300-K self-focusing data of Nowak and Ham [Opt. Lett. 6, 185 (1981)] at CO(2)P(28), P(20), and P(10) in SF(6). Calculations with a two-dimensional diffraction-propagation code show good quantitative agreement with the Nowak and Ham data at CO(2)P(20) and P(10).
Formulation of the drift reliability optimization problem

Abstract Drift Reliabilty (DR) of a system is related to that part of the overal system reliability that is concerned with the system element ageing and parameter dependence on such environmental conditions as temperature, level of radiation, humidity, etc. Its maximization during the system design phase is of great economic importance for the manufacturers of electronic products and other equipment. In this paper the DR optimization problem is mathematically formulated in the context of parametric manufacturing yield optimization, and some algorithmic aspects of its solution are discussed. It is shown that it is possible to formulate the problem in such a way that some measures of both the yield and the average time to failure (due to the system element drift) can be maximized, and different trade-off situations investigated. The existing efficient gradient based yield optimization algorithms can be used after only some relatively simple modifications of the gradient estimation formulas.
Mouse T-cell surface glycoprotein recognised by heterologous anti-thymocyte sera and its relationship to Thy-1 antigen

CELL surface proteins specific for either T or B lymphocytes probably have a significant role in lymphocyte physiology, and we have therefore been characterising the plasma membrane proteins from mouse lymphocytes to identify such molecules and to determine their function. We have previously detected a high molecular weight T-cell-surface protein (T200, apparent molecular weight 200,000) which could be labelled by lactoperoxidase-catalysed iodination1 and was recognised by rabbit anti-mouse thymocyte sera (ATS). We have now identified a low molecular weight T-cell-specific molecule present on mouse thymocytes, T lymphomas and peripheral T cells which is also recognised by rabbit antibodies to mouse lymphocytes.
Impact of gate stack on the stability of normally-Off AlGaN/GaN power switching HEMTs

We have examined the response of AlGaN/GaN power switching HEMTs to electrical bias stress. Three different gate stack structures were studied. In devices containing a ~ 5 nm thick AlGaN layer in the gate stack, both positive and negative shifts in the threshold voltage were observed following high blocking voltage stress, consistent with a short initial period of electron trapping followed by a longer period of de-trapping. Correlated changes in reverse bias leakage current were also observed, although this also occurred in devices containing only residual AlGaN in the gate stack. The data have been explained by a field-enhanced emission model in which an electron trapping to de-trapping transition occurs. The exact nature of the transition is found to be sensitive to a variety of parameters including trap energy, geometry, and initial and boundary conditions.
The close relation between Antarctic total‐ozone depletion and cooling of the Antarctic low stratosphere

Nearly 5500 mean-monthly low-stratospheric temperatures at 100, 50 and 30 mb at 16 Antarctic stations have been extracted from "Monthly Climatic Data for the World" for the interval 1958-1985. About 450 mean-monthly total-ozone values at 4 Antarctic stations have been extracted from "Ozone Data for the World" for the same interval. There has been an impressive in-phase relation between seasonal variations in low-stratospheric temperature and total ozone in Antarctica. This relation extends not only to the large total-ozone and low-stratospheric temperature decreases since 1978 in the Southern Hemisphere spring (approximately 30% and 6-8°C, respectively, based on smoothed data), but also to relatively minor fluctuations in this and other seasons. The springtime stratospheric temperature decreases since 1978 are indicated to have been greatest along the Antarctic coast between about 30°W and 60°E, including the stations of Halley Bay and Syowa; there has been practically no low-stratospheric temperature decrease at stations 10 degrees of latitude further north on the Antarctic Peninsula. The springtime temperature decrease has been pretty much confined to the Antarctic stratosphere, or to levels above about 300 mb.
Studies on the action of porphyrinogenic trace metals on the activity of hepatic uroporphyrinogen decarboxylase.

Abstract Trace metals which produce experimental uroporphyrinuria in animals during prolonged exposure inhibit uroporphyrinogen (uro) decarboxylase in rat liver extracts in , vitro . Inhibitory effects are prevented by sulfhydryl reagents, suggesting metal binding to sulfhydryl groups of the enzyme as the likely mode of action. Mercury, the most potent of the metals tested with respect to sulfur binding kinetics, produces the greatest inhibition of enzyme activity. In contrast, iron, which is considered to play a role in the etiology of porphyria cutanea tarda (PCT) via inhibition of uro decarboxylase, did not inhibit the enzyme in the present test system, suggesting an indirect mode of action in , vivo . These results suggest that direct inhibition of uro decarboxylase underlies uroporphyrinuria produced by prolonged trace metal exposure. Experimental inhibition of uro decarboxylase by trace metals may serve as a model for studying metal-induced uroporphyrinuria and PCT in humans.
Distinct functions of Rho and Rac are required for convergent extension during Xenopus gastrulation

We have undertaken the first detailed analysis of Rho GTPase function during vertebrate development by analyzing how RhoA and Rac1 control convergent extension of axial mesoderm during Xenopus gastrulation. Monitoring of a number of parameters in time-lapse recordings of mesoderm explants revealed that Rac and Rho have both distinct and overlapping roles in regulating the motility of axial mesoderm cells. The cell behaviors revealed by activated or inhibitory versions of these GTPases in native tissue were clearly distinct from those previously documented in cultured fibroblasts. The dynamic properties and polarity of protrusive activity, along with lamellipodia formation, were controlled by the two GTPases operating in a partially redundant manner, while Rho and Rac contributed separately to cell shape and filopodia formation. We propose that Rho and Rac operate in distinct signaling pathways that are integrated to control cell motility during convergent extension.
Lean body mass in twins

A study of 49 pairs of monozygous (MZ) twins and 38 pairs of same-sexed dizygous (DZ) twins showed that lean body mass (LBM), as determined by potassium 40 counting, is under genetic influence. Intrapair variances for LBM are much smaller than those for body fat, which suggests that LBM has a higher degree of heritability. There is a correlation between the magnitude of intrapair LBM differences and intrapair weight differences for both sets of twins, showing that environment is also an important influence. The effect of weight variation on LBM variation is greater for thin people than for those with appreciable burdens of body fat, an observation previously made on individuals who undergo a nutrition-induced weight change.
Formal operations: A systematic reformulation

In the present paper it is argued that the original model of formal operations failed to make a clear distinction between the organization of knowledge and the ability to solve tasks. Additionally, too much emphasis was placed on the scientific reasoning aspect of formal operations in previous accounts. The present paper proceeds by first describing a recasted model of formal operations which retains only its essential, nondeletable aspects. Relevant empirical literature is reviewed within the perspective of this recasted model. Then, some positive heuristics, i.e., methodological approaches designed to avoid anomalous results, are proposed as direct tests of this model. Finally, the similarity and differences between the present account and other accounts of formal operations are discussed.
Light Response of a Giant Aplysia Neuron

Illumination of an Aplysia giant neuron evokes a membrane hyperpolarization which is associated with a membrane conductance increase of 15%. The light response is best elicited at 490 nM: the neuron also has an absorption peak at this wavelength. At the resting potential (-50 to -60 mV) illumination evokes an outward current in a voltage-clamped cell. This current reverses sign very close to EK calculated from direct measurements of internal and external K+ activity. Increases in external K+ concentration shift the reversal potential of the light-evoked response by the same amount as the change in EK. Decreases in external Na+ or Cl- do not affect the response. Therefore, the response is attributed to an increase in K+ conductance. Pressure injection of Ca2+ into this neuron also hyperpolarizes the cell membrane. This effect is also due largely to an increase in K+ conductance. The light response after Ca2+ injection does not appear to be altered. Pressure injection of EGTA abolished or greatly reduced the light response. The effect was reversible. We suggest that light acts upon a single pigment in this neuron, releasing Ca2+ which in turn increases K+ conductance, thereby hyperpolarizing the neuronal membrane.
IDENTIFYING TREATMENT EFFECTS UNDER DATA COMBINATION

We consider the identification of counterfactual distributions and treatment effects when the outcome variables and conditioning covariates are observed in separate data sets. Under the standard selection on observables assumption, the counterfactual distributions and treatment effect parameters are no longer point identified. However, applying the classical monotone rearrangement inequality, we derive sharp bounds on the counterfactual distributions and policy parameters of interest.
Swabbing students: Should universities be allowed to facilitate educational DNA testing?

Recognizing the profound need for greater patient and provider familiarity with personalized genomic medicine, many university instructors are including personalized genotyping as part of their curricula. During seminars and lectures students run polymerase chain reactions on their own DNA or evaluate their experiences using direct-to-consumer genetic testing services subsidized by the university. By testing for genes that may influence behavioral or health-related traits, however, such as alcohol tolerance and cancer susceptibility, certain universities have stirred debate on the ethical concerns raised by educational genotyping. Considering the potential for psychosocial harm and medically relevant outcomes, how far should university-facilitated DNA testing be permitted to go? The analysis here distinguishes among these learning initiatives and critiques their approaches to the ethical concerns raised by educational genotyping.
Establishment and characterization of a telomerase immortalized human gingival epithelial cell line.

Background and Objective Gingival keratinocytes are used in model systems to investigate the interaction between periodontal bacteria and the epithelium in the initial stages of the periodontal disease process. Primary gingival epithelial cells (GECs) have a finite lifespan in culture before they enter senescence and cease to replicate, while epithelial cells immortalized with viral proteins can exhibit chromosomal rearrangements. The aim of this study was to generate a telomerase-immortalized human gingival epithelial cell line and compare its in vitro behavior to that of human GECs.
Time‐reversal acoustics and maximum‐entropy imaging

A common problem in acoustics imaging is target location using either passive or active data inversion. Time‐reversal methods in acoustics have the important characteristic that they provide a means of determining the eigenfunctions and eigenvalues of the scattering operator for either of these two cases. Each eigenfunction may often be approximately associated with an individual scatterer. The resulting decoupling of the scattered field from a collection of targets is a very useful aid to localizing the targets, and suggests a number of imaging and localization algorithms. Two of these are linear subspace methods and maximum‐entropy imaging.
Microemulsions as nanoreactors to produce whey protein nanoparticles with enhanced heat stability by thermal pretreatment

Abstract Native whey proteins (NWPs) may form gels or aggregates after thermal processing. The goal of this work was to improve heat stability of NWPs by incorporating protein solutions in nanoscalar micelles of water/oil microemulsions to form whey protein nanoparticles (WPNs) by thermal pretreatment at 90 °C for 20 min. The produced WPNs smaller than 100 nm corresponded to a transparent dispersion. The WPNs produced at NWP solution pH of 6.8 had a better heat stability than those produced at pH 3.5. The salt concentration (0–400 mM NaCl) in NWP solutions did not significantly change the size of corresponding WPNs. Compared to NWPs, the 5% (w/v) dispersion of WPNs at pH 6.8, 100 mM NaCl did not form a gel after heating at 80 °C for 20 min. The improved heat stability and reduced turbidity of WPNs may enable novel applications of whey proteins in beverages.