cssi/SciSciGPT-SciSciNet huggingface dataset:
Temporal coupling between subicular and hippocampal neurons underlies retention of trial-specific events.

Abstract The subiculum receives the majority of efferent outflow of neural information from the CA1 region of the hippocampus. As such it occupies a strategic position in which to integrate, transfer and resolve activity from the hippocampus relating to memory and performance. We have previously demonstrated that each structure has complementary ensemble firing patterns that together allow information to be represented continuously over the time course of a trial in a delayed-non-match-to-sample (DNMS) task. Here, we extend this analysis to show the precise manner in which specific neurons in both structures are coupled temporally across the delay interval on a single trial. Neurons in both structures encode position-specific information related to the sample lever press, but only subicular neurons continue to fire during the early portion of the subsequent variable delay interval. However, cross-correlation analysis of multiple spike trains showed that as the delay increased in duration other subicular neurons were temporally coupled to the subicular neurons that fired in the initial part of the delay. This latter population of subicular neurons showed strong cross-correlated firing with other initially activated subicular neurons until midway through the delay (
Cloning and characterization of the subunits comprising the catalytic core of the Trypanosoma brucei mitochondrial ATP synthase.

The Trypanosoma brucei mitochondrial F1-ATPase has been previously isolated and characterized. It is composed of five subunits of molecular weights 55 000, 42 000, 32 000, 22 000, and 17 000 [1]. We have identified the α and β subunits of the T. brucei F1-ATPase by N-terminal sequence determination together with analysis of cDNA and genomic clones. The genes for both subunits are homologous to the same subunits from other organisms. They contain the Walker A and B boxes of homology and a putative mitochondrial import sequence. The isolated T. brucei α subunit is unusually small at 42 kDa. The α cDNA clone encodes a protein of predicted size 59 kDa with a mitochondrial import presequence at the N-terminus. The predicted size was confirmed by expression of a 59 kDa protein from the cDNA clone in vitro. These results suggest that the α subunit may have an unusually large mitochondrial presequence of 159 amino acids. In contrast, the estimated size of the native β subunit (55 kDa) correlates well with the size predicted from the cDNA clone, 57 kDa, from which a 21 amino acid presequence has been removed in vivo. The size of the β subunit was confirmed by expression in an in vitro and an Escherichia coli expression system. The purified recombinant β subunit, like the native F1-ATPase, can be labeled by the photoaffinity nucleotide analogue 8-azido ATP. Binding of the 8-azido ATP probe is best competed by the natural substrate ATP, and is significantly reduced by pretreatment with the inhibitor 7-chloro-4-nitrobenzo-2-oxa-1,3-diazide as has been shown with β subunits of other organisms. The differential binding of this photoaffinity analogue was used to resolve the identities of the α and β subunits of the ATP synthase from T. brucei. These results are in contrast to results previously obtained for a related trypanosomatid Crithidia fasciculata.
Dynamic light-scattering study of an ethylene–methacrylic acid copolymer and its salt

Dynamic light-scattering experiments were performed on an ethylene–methacrylic acid copolymer and its sodium salt. The in-phase ΔI′ and out-of-phase ΔI″ components of the light scattering were measured in a temperature range between 25 and 65°C for both samples. No transition is seen in this temperature interval for the acid, but a clear transition occurs around 40°C for the salt. This transition is associated with the softening point of the ionic domains present in the sample.
Physics of electronic transport in low-dimensionality materials for future FETs

We show that scaling rules, quantum confinement in thin bodies, and the resulting gate leakage render imperative the use of low-dimensionality materials as channels in devices scaled beyond the 10 nm gate length. We then consider a few examples of two-dimensional materials of great interest, graphene and bilayer graphene, and show how the dielectric environment (gate and interlayer insulators, nearby gates) has a dramatically strong effect on the electronic properties of systems such as supported graphene, nanoribbons, and graphene bilayers in which a Bose-Einstein exciton condensation has been predicted to occur at high temperature. Finally, we consider the novel concept of devices based on monolayer tin (‘stannanane’) as a topological insulator.
Effect of allergen avoidance in infancy on allergic manifestations at age two years.

Abstract Background: One hundred twenty children, identified before birth as being at high risk for atopy, were prenatally assigned to prophylactic or control groups. Methods: The infants in the prophylactic group either received breast milk from mohters on an exclusion diet or an extensively hydrolyzed formula. Their bedrooms and living rooms were treated repeatedly with an acaricide, and they used polyvinyl-covered mattresses with vented head areas. The infants in the control group were fed conventionally, and no environmental control was recommended. Results: A significant advantage, first demonstrated at 1 year of age, persists for children in the prophylactic group. They have less of any allergy or eczema, but the reduced prevalence of asthma is no longer significant. Only three children in the prophylactic group had positive skin prick test results compared with 16 in the control group, suggesting a significant reduction in sensitization. Conclusion: A dual approach to allergen avoidance, focusing on foods and aeroallergens, appears to be beneficial in selected high-risk infants. Avoidance of potent allergens in early life increases the threshold for sensitization in these high-risk infants. Whether sensitization has been avoided or merely deferred has yet to be proved.
Rate, predictors, and consequences of hemodynamic depression after carotid artery stenting.

Objectives We sought to determine the frequency, predictors, and consequences of hemodynamic depression (HD) after carotid artery stenting (CAS). Background Hemodynamic depression has been reported after carotid artery stenting CAS and carotid endarterectomy (CEA). Methods We retrospectively analyzed data on 500 consecutive CAS procedures performed over a 5-year period. Hemodynamic depression was defined as periprocedural hypotension (systolic blood pressure Results The mean age of the patients was 70.5 ± 10 years, and 69% were men. Hemodynamic depression occurred during 210 procedures (42%), whereas persistent HD developed in 84 procedures (17%). Features that independently predicted HD included lesions involving the carotid bulb (odds ratio [OR] 2.18 [range 1.46 to 3.26], p Conclusions Hemodynamic depression is common after CAS, particularly in patients with a calcified plaque in the carotid bulb, but is easily treated with conventional methods. Patients who develop persistent HD are at an increased risk of periprocedural major adverse clinical events and stroke.
Axial gynandromorphy and sex determination in Branchinecta lindahli (Branchiopoda: Anostraca)

In the Crustacea, sex determination is generally considered to be cell non-autonomous, with a centralized sex differentiation signaling system. However, observed frequencies of axial (anterior-posterior) morphological gynandromorphs of Branchinecta lindahli Packard, 1883 suggest cell autonomous sex determination. Thoracic appendages of seven Branchinecta lindahli axial gynandromorphs with male second antennae and female genitalia were compared to normal male and female thoracic appendages to quantitatively determine if the putative gynandromorphs showed evidence of intersexuality. None of the gynandromorphs showed evidence of intersexuality, supporting the occurrence of cell autonomous sex determination in branchiopod crustaceans.
An assessment of the effect of chemical scavenging within submarine hydrothermal plumes upon ocean geochemistry

Profiles of 210Pb over the Endeavour and North Cleft Segments of the Juan de Fuca Ridge are used to model a time scale for the scavenging, by hydrothermal plumes, of reactive elements in seawater. The hydrothermal plumes above these ridge segments are sites of intense scavenging removal of 210Pb. At Endeavour, the total 210Pb activities within the plume are as low as 8 dpm/100 l and dissolved activities are as low as 3 dpm/100 l. At the North Cleft, which is characterized by higher particulate Fe concentrations, the total 210Pb activities are 4.5 dpm/100 l, the dissolved activities are 1–2 dpm/100 l and the 210Pb activities are deficient with respect to the activity of the 210Po daughter. These are perhaps the lowest 210Pb activities ever measured in the deep sea. The large gradient of 210Pb between the plume and surrounding deep water suggests that scavenging is focused into the plumes through horizontal transport. The implication, therefore, is that this process might impact the ocean on a scale larger than that local to the ridge crest. By coupling published measurements of particle flux from Endeavour with 210Pb activities on particles trapped at that site, the total volume of seawater stripped of 210Pb per year for that site was calculated to be 7.4 × 1012 l/y. Globally, the extrapolated volume flux of seawater stripped of reactive constituents is 5.7 × 1015 l/y, such that the entire ocean is processed in this manner in 2.4×105 y. The geochemical cycle of elements with ocean residence times much shorter than this (e.g., Pb and Th) will not be greatly affected by hydrothermal scavenging. On the other hand, this process holds significance for the geochemistry of other elements scavenged by hydrothermal plumes, such as P and V, whose ocean residence times are > 104 y.
State of infection prevention in US hospitals enrolled in the National Health and Safety Network.

Background: This report provides a national cross-sectional snapshot of infection prevention and control programs and clinician compliance with the implementation of processes to prevent health caree associated infections (HAIs) in intensive care units (ICUs). Methods: All hospitals, except Veterans Affairs hospitals, enrolled in the National Healthcare Safety Network (NHSN) were eligible to participate. Participation involved completing a survey assessing the presence of evidence-based prevention policies and clinician adherence and joining our NHSN research group. Descriptive statistics were computed. Facility characteristics and HAI rates by ICU type were compared between respondents and nonrespondents. Results: Of the 3,374 eligible hospitals, 975 provided data (29% response rate) on 1,653 ICUs, and there were complete data on the presence of policies in 1,534 ICUs. The average number of infection preventionists (IPs) per 100 beds was 1.2. Certification of IP staff varied across institutions, and the average hours per week devoted to data management and secretarial support were generally low. There was variation in the presence of policies and clinician adherence to these policies. There were no differences in HAI rates between respondents and nonrespondents. Conclusions: Guidelines for IP staffing in acute care hospitals need to be updated. In future work, we will analyze the associations between HAI rates and infection prevention and control program characteristics,
Palaeolithic Grandmothers? Life History Theory and Early Homo

The acknowledged success of early Homo has generally been thought to reflect male-dominated provisioning and associated patterns of co-operative social organization; recently, however, such conclusions have been challenged with the argument that post-menopausal females, instead, played a significant role in early human subsistence activities; males, it has been proposed, had a very minor role in food acquisition in early Homo. The fossil record, however, indicates minimal old-age survivorship of either sex and heavy young adult mortality, a pattern which is also seen in larger prehistoric and ethnographic samples. Heavy young adult mortality, when combined with characteristically slow maturation, represents a paradox which humans have solved through new reproductive strategies (early weaning and alloparenting) and new life history stages (childhood and adolescence). Stone tools, when used to acquire marrow and brain tissue to feed needful youngsters, may also have been among the strategies developed in response to frequent early parental death.
Introduction: Urban History, Arnold Hirsch, and the Second Ghetto Thesis

The death of American historian Arnold Hirsch, in 2018, generated multiple reexaminations of his profoundly influential “second ghetto thesis.” Hirsch’s landmark Making the Second Ghetto: Race and ...
Structure of Firm Location Choices: An Examination of Japanese Greenfield Investment in China*

This paper presents an empirical investigation of the location decision structure of Japanese investors in China. In this study, a nested logit model and rich Japanese firm-level greenfield manufacturing foreign direct investment data are calibrated together. This examination is not only driven by the unsatisfactory model specification of the conditional logit model in previous location choice analyses, specifically the violation of the independence from irrelevant alternatives assumption; but is also driven by the urgent need to better understand foreign investors’ in general and Japanese investors’ in particular location decision structure in China. Two potential hierarchical and sequential location decision-making structures of Japanese investors are then tested, which are respectively in line with the spatial divide of China's FDI preferential policies and with China's six traditional census areas.
Establishing a Quality Control Program: Ensuring Safety from Contamination for Recycled Metered-Dose Inhalers:

Background: Recycling metered-dose inhalers (MDIs) is an effective method to conserve medications resulting in significant cost savings to the hospital. A noted limitation in some reports is the potential for cross-contamination. Objective: To implement a quality control program to monitor and validate the safety of recycled MDIs for institutional reuse. Methods: A quality control program was conducted from December 2012 to May 2013. At a 257-bed acute care facility, MDIs are administered to a single patient using a patient-specific valved holding chamber and then returned to the pharmacy for cleaning with 70% isopropyl alcohol prior to re-dispensing to a new patient. Ten percent of MDIs from 3 categories were categorized: prior to pharmacy cleaning, after pharmacy cleaning, and new/unused control group each month. The mouthpiece and canister spray tip from each MDI were tested. Any bacterial growth was documented. A secondary test was conducted to ensure that artificially contaminated MDIs could be clean...
WE-G-BRA-02: Visual Demonstrations of Medical Physics Concepts of Transmission Imaging for Resident Education.

Purpose: To improve the radiology residents' understanding of medical physics concepts through visualization of physical phenomena. Methods: Several medical physics concepts in x‐ray transmission imaging are relevant to many radiographic modalities, not only to planar radiography. Therefore, it is important that the diagnostic radiology residents obtain a good understanding of these concepts. However, standard PowerPoint slides or blackboard‐based graphical representations are not always effective ways to communicate these novel concepts to the residents. To improve upon the understanding of these concepts, the computer, projector and screen in the lecture room are used as surrogates of an x‐ray imaging system. The projector is the source of light (x‐rays) with PowerPoint slides defining the pattern emitted (x‐ray field) on to the projector screen (detector/monitor). Several different transparencies and acrylic objects are used to demonstrate varied medical physics phenomena relevant to transmission imaging, such as: straight‐line travel of electromagnetic radiation; tissue superimposition; object, subject, image and display contrast; linear systems; point spread functions; frequency domain; contrast and modulation transfer functions; quantum and imagenoise;noise frequency and noise power spectrum; anatomical noise; magnification and geometric unsharpness; inverse square distance relationship; sampling and aliasing; and x‐ray scatter. Results: The residents' comprehension and ability to explain these concepts has substantially improved, in addition to their interest in these topics. This was reflected on improved test scores and on anonymous feedback surveys post‐ lectures.Conclusions: The use of demonstrations that mimic the conditions and physical phenomena found in transmission imaging by taking advantage of the projector and screen together with transparencies and other objects improves the residents' grasp of basic radiographic concepts and promotes live interactions between the residents and the medical physicist. Additional concepts that can be demonstrated in this manner are being sought.
Service Recovery Strategies: The Impact of Cultural Differences:

Relationship marketing and economies of scope are predicted to become the next major shift in organizational practice. The service recovery concept is a major element in effective implementation of both. This article integrates current knowledge in the area of service recovery with existing knowledge pertaining to the effect of culture on consumer behavior. With the increasing globalization of our customer base, the exploration of service recovery within the context of culture is both timely and important.
Kinetic Theory Explanation of a Circulating Fluidized Bed Ring Structure near Choking

The objective of this technical note is to give an alternate explanation of the ring structure behavior for the flow of fluidized catalytic cracking (FCC) particles in a riser recently obtained in L. S. Fan’s laboratory. Their recent explanation of this phenomenon is due to the low velocity at the center. While indeed this is one of the causes of the high concentration near the center, we show that an additional driving force for the higher concentration at the center is the low granular temperature caused by the dissipation of random kinetic energy at the center of the riser. An approximate analytical solution applied to the flow of FCC particles obtained in Fan’s laboratory again produces a dip in the granular temperature in the center and hence a rise in the particle concentration. This phenomenon occurs as a result of the constancy of solids pressure in the developed region of the riser. It is the so-called shear-induced diffusion effect well-known for neutrally buoyant particles in liquids.
Crystal and molecular structure of 6‐(p‐bromobenzoyl)‐6‐azabicyclo[3.1.0]hexane

The molecular structure of 6-(p-bromobenzoyl)-6-azabicyclo[3.1.0]hexane has been determined by a single crystal, three-dimensional x-ray study. The compound crystallizes in the monoclinic space group (P) with four molecules in a unit cell of dimensions a = 8.83, b = 10.15, c = 12.63 ± 0.02A and β = 94°55′ ± 5′. The aziridine ring is eis fused to the cyclopentane ring with the two rings together in a boat conformation. The fusion angle of the two rings is 110.8°. The aziridine ring has all angles of 60 ±1° and all bond distances of 1.48 ± 0.03A. The cyclopentane ring has alternately long (1.61 ± 0.04A) and short (1.52 ± 0.02A) distances. Non-fusion angles in the cyclopentane ring are 106.0 ± 0.5°. Other molecular parameters are as anticipated. The 844 independent reflections obtained were refined to a final value of R = 0.116 using full-matrix least squares techniques.
Income Sensitivity of Price Elasticities: Effects On the Demand for Public Goods

This article investigates the effect of income on the price elasticity of demand Abstract for public goods. While this elasticity is normally treated as identical for different income groups, the findings of this article show that such a view is incorrect, and that price elasticity is functionally related to income. To do so, a measure for the income elasticity of price elasticity is defined; empirical measures, based on a model that transforms referendum results into measures of demand, are then found for eight categories of public goods. The results show that most of these elasticities are negative, i.e., that the negative effect of tax price increases on demand for public goods becomes larger with higher income, but that, for the jurisdiction that was investigated, the opposite is the case for government expenditures on education and culture. Upper-income groups are more cost-conscious than the poor in most public goods, except for educational and cultural expenditures.
Posttranslational Regulation of Surfactant Protein B Expression

Although a minor constituent by weight, surfactant protein B (SP-B) plays a major role in surfactant function. It is the unique structure of SP-B that promotes permeabilization, cross-linking, mixing, and fusion of phospholipids, facilitating the proper structure and function of pulmonary surfactant as well as contributing to the formation of lamellar bodies. SP-B production is a complex process within alveolar type 2 cells and is under hormonal and developmental control. Understanding the posttranslational events in the maturation of SP-B may provide new insight into the process of lamellar body formation and into the pathophysiology of pulmonary disorders associated with surfactant abnormalities.
Human insulin-like growth factor binding protein-1 (hiGFBP-1) transgenic mice: Insights into hIGFBP-1 regulation and actions

Abstract Three hemizygous transgenic (Tg) mouse lines were generated with a fusion gene composed of the mouse metallothionein promoter (mMT-1) and a full length human insulin-like growth factor binding protein-1 (hIGFBP-1) cDNA that was truncated in its 3′ untranslated (3′UT) region. The transgene was ectopically expressed in the brain of each line and resulted in postnatal brain-growth retardation that was manifested by 2 weeks of age. Despite the expression of the transgene in multiple other tissues and high serum hIGFBP-1 concentrations in two of the three lines, studies designed to detect alterations in somatic growth, in reproduction and in glucose metabolism revealed few other abnormalities. Unexpectedly, however, we found that the regulation of the transgene shared characteristics with that of the native gene, despite the fact that it lacked the endogenous gene's 5′ regulatory region, as well as most of its 3′ UT region. Our studies suggest that factors controlling mRNA stability are important to regulation of both the native and transgene, and that an AU-rich element 17 base pairs (bp) from the end of coding sequence is responsible for the instability of the transgene and in part for instability of the endogenous gene.
Who/se we are: baptism as personhood

The attempt to arrive at some consensus on precisely what qualifies a human as a persons represents one of the more persistently debated and widely significant issues in modern biomedical ethics. The attribution of personhood has been and continues to be a powerful tool in moral discourse. Biomedical and bioethical debates about personhood seem especially morally significant in late modernity given the recent trends in biomedical technology. Our attempts to formally articulate universally agreed upon criteria for personhood represent some of the last vestiges of the hope that we can achieve substantial moral agreement in an otherwise morally fragmented world. In this essay, we argue that, from the perspective of certain strands of the Christian tradition, all bioethics grounded in attempts to develop formal, objective criteria by which we may designate a given individual a person are misguided. Criteria centering on the possession of reflective mental capacity, moreover, are for Christians especially problematic. We suggest that there are no morally neutral ways of designating personhood.
Introduction to special issue on instructional technology and teacher education

Teacher education was a completely separate academic unit-usually located somewhere in the nether regions of the university where the faculty put in numerous hours training and supervising preservice teachers. The two lived quite happily in separate worlds, neither really knowing-or caring to know-what the other was doing. You may recognize some traces of truth in my exaggerated depiction of the disconnect between IT and teacher education programs. Some of the separation is quite understandable, even predictable. Each discipline is distinct and driven by very different missions. But political and economic realities have forced a blurring of the lines between the two fields that should be
Delay line microchannel plate detectors for the far-ultraviolet spectroscopic explorer satellite

Delay line detectors have been chosen for the Far Ultraviolet Spectroscopic Explorer1 mission to be launched in 2000. The demands of the FUSE detectors include large format (220mm x 10mm format), high spatial resolution (15im x 35im FWHM) and linearity, high image stability, low power consumption and weight, and counting rates in excess of 3 x i0 events sec1. The FUSE program builds on the previous work, which includes two delay line detectors (95mm x 27mm double delay line format) that have already been successfully employed in the ORFEUSASTROSPAS2 ultraviolet spectrometer launched by shuttle in September 1993. We present the plans for the FUSE detector program, and results from double delay line (DDL) detectors that are under investigation to meet the requirements of the FUSE program. Our current detector achieves 15im x 25p,m FWHM (<4000 x 500 resolution elements) over the 65 x 15mm format used for the FUSE demonstration detector (90% of the flight detector segment format length), with good linearity (±1 resolution element) and high stability. State of the art analog to digital converter (ADC), gated integrator, and digital signal processor (DSP) technology have been employed to develop novel event position encoding electronics with high count rate capability (<5 x104 events sec). Microchannel plates with lOj.tm pores and an 80: 1 pore length to diameter ratio, with a 70mm x 20mm format have been used in a Z stack configuration to provide the photon amplification (gain 2 x 10). These show good pulse height distributions (<35% FWHM) even with uniform flood illumination, and background levels typical for this configuration (<1 event cm 2 sec 1). Flat field images are dominated by the microchannel plate fixed pattern noise due to the multifiber boundaries, and are stable. High efficiency photocathodes, such as KBr have been extensively studied, and provide quantum detection efficiencies of 40-50% in the 900 - 1200A range for FUSE.
Use of cyclodextrin to deliver lipids and to modulate apolipoprotein B-100 production in HepG2 cells.

2-Hydroxypropyl-β-cyclodextrin (cyclodextrin), cyclodextrin-solubilized oleate, and cyclodextrin-solubilized cholesterol were used to modulate proteolysis and secretion of newly-synthesized apolipoprotein B-100 (apoB) in HepG2 cells. Following cyclodextrin and lipid treatments, cells were pulse-labeled with [3H] leucine, and quantitative immunoprecipitation was used to measure apoB synthesis, apoB secreted into the medium, and the cellular content of undegraded apoB that was not secreted. Three-hour treatment with cyclodextrin-solubilized oleate (0.2 mM) increased secreted apoB from 4% (control cells) to 32% and cellular undegraded apoB from 15% (control cells) to 64% of apoB synthesized, which is consistent with earlier studies using bovine serum albumin to complex exogenous oleate. Prolonged daily (4 d or more) administration of 0.5% (3.5 mM) cyclodextrin with medium containing 10% fetal bovine serum increased the secretion of nascent apoB from 5–10% (control) to 17–28% and cellular undegraded apoB from 15–20% (control) to 25–31% of apoB synthesized, respectively. Subsequent administration of cyclodextrin-solubilized cholesterol (10–40 μg) for only 3 h reversed the cyclodextrin-mediated increase in apoB secretion. The application of 0.5% cyclodextrin to HepG2 cells can rapidly (within minutes) stimulate cholesterol efflux, and transiently (over a 1–2 d period) increase cholesterol synthesis. In the current studies, the cyclodextrin-mediated increase in cholesterol synthesis was not concurrent with the increase in apoB secretion. However, prolonged (15 d) administration of cyclodextrin was shown to increase the cellular free cholesterol concentration by 25–41%, reduce the cellular triglyceride concentration by 59% and increase apoB secretion 3- to 4-fold, without affecting the cellular cholesteryl ester concentration. In comparison, 14-d treatment with cyclodextrin-solubilized cholesterol (20 μg/mL) followed by 1-d equilibration without cholesterol was shown to increase the cellular free cholesterol and cholesteryl ester concentrations by 76% and 10-fold, respectively, although apoB secretion was not affected. It is hypothesized that chronic daily administration of 0.5% cyclodextrin increased the cellular cholesterol concentration and flux in discrete putative regulatory compartment which “shielded” nascent apoB from rapid proteolysis and facilitated apoB secretion. In conclusion, cyclodextrin was used independently and in combination with cholesterol or oleate to modulate apoB proteolysis and secretion. We speculate that subcellular changes in cholesterol concentration and flux may modulate apoB production in HepG2 cells.
Electron interferometry from voids in spinel

Abstract Voids in spinel can act as perfectly aligned double crystal interferometers. The electron interference patterns can be obtained by using a conventional TEM instrument operating in the convergent beam electron diffraction (CBED) mode. The study of the lattice fringes in the 2 beam case and in the case of [111] zone axis patterns (ZAPs), are reported. The (000) disc in CBED ZAPs shows a simple hexagonal pattern with an angular separation of ≈ 10 -4 rad. The contrast within the (000) disc depends on the angle of convergence. A method for void size determination in the direction of the beam is presented.
Phonological treatment of naming deficits in aphasia: Model-based generalization analysis

Abstract A phonologically based treatment was implemented to train oral picture naming in four aphasic subjects with severe word-retrieval deficits. An initial assessment based on current cognitive neuropsychological models of naming indicated different levels of phonological and/or semantic deficits underlying naming failure across the subjects. Using a single-subject multiple baseline design across behaviours and subjects, the effects of treatment were evaluated by daily probing of both trained and untrained items across lexical tasks: oral naming, oral reading, and written naming. Results indicated successful acquisition of trained naming targets for the four subjects, and varied patterns of response generalization to naming of untrained phonologically and semantically related pictures, and to oral reading and written naming for the same words. Baseline levels of oral reading performance were noted to predict success in oral naming treatment. Differences in generalization patterns across tasks are disc...
Retaining sandbox containment despite bugs in privileged memory-safe code

Flaws in the standard libraries of secure sandboxes represent a major security threat to billions of devices worldwide. The standard libraries are hard to secure because they frequently need to perform low-level operations that are forbidden in untrusted application code. Existing designs have a single, large trusted computing base that contains security checks at the boundaries between trusted and untrusted code. Unfortunately, flaws in the standard library often allow an attacker to escape the security protections of the sandbox.In this work, we construct a Python-based sandbox that has a small, security-isolated kernel. Using a mechanism called a security layer, we migrate privileged functionality into memory-safe code on top of the sandbox kernel while retaining isolation. For example, significant portions of module import, file I/O, serialization, and network communication routines can be provided in security layers. By moving these routines out of the kernel, we prevent attackers from leveraging bugs in these routines to evade sandbox containment. We demonstrate the effectiveness of our approach by studying past bugs in Java's standard libraries and show that most of these bugs would likely be contained in our sandbox
Observation of quantum destructive interference in inelastic two-wave mixing.

Using room-temperature Rb-87 atoms we demonstrate a quantum destructive interference between two one-photon excitation pathways in an inelastic two-wave mixing scheme that corresponds to the "strong-storage and weak-retrieval" of an optical field. This destructive interference is fundamentally different from the usual electromagnetically induced transparency because it is critically dependent on the generation and propagation of a wave-mixing field. We also show that contrary to the common belief, the maximum atomic coherence in general does not lead to the maximum mixing-wave conversion efficiency.
Preadipocyte Recruitment in Stromal Vascular Cultures After Depletion of Committed Preadipocytes by Immunocytotoxicity

Glucocorticoids or the glucocorticoid analog dexamethasone (DEX) enhances the differentiation of preadipocytes in the presence of insulin and influences preadipocyte proliferation. The purpose of the present study was to determine if DEX can induce the recruitment of preadipocytes. Using monoclonal antibodies for complement-mediated cytotoxicity, preadipocytes were removed from porcine stromal vascular (S-V) cell cultures. Our experiments demonstrated for the first time that after removal of preadipocytes by cytotoxicity, preadipocytes or fat cells could be induced by DEX or DEX plus insulin but not by insulin alone. However, many more fat cells were induced (258 +/- 15/unit area) when DEX was added with fetal bovine serum (FBS) followed with insulin treatment, compared to DEX with insulin (21.3 +/- 5.1/ unit area) after removal of preadipocytes. Immunocytochemistry with AD-3, a preadipocyte marker, showed that DEX with FBS for 3 days after seeding (i.e., the proliferation phase) produced many more preadipocytes (AD-3 positive, 223 +/- 45/unit area) than FBS alone (10.5 +/- 1.4/unit area). Bromodeoxyuridine (BrdU) incorporation assays demonstrated that the efficiency of DEX with FBS (i.e., during proliferation) was mitosis dependent. Accordingly, we conclude that: porcine S-V cultures contain preadipocytes at different stages of differentiation; and that DEX induced early preadipocyte differentiation depends on mitosis.
Substrate Ambiguity of 3-Deoxy-d-manno-Octulosonate 8-Phosphate Synthase from Neisseria gonorrhoeae in the Context of Its Membership in a Protein Family Containing a Subset of 3-Deoxy-d-arabino-Heptulosonate 7-Phosphate Synthases

3-Deoxy-d-manno-octulosonate 8-phosphate (KDOP) synthase and 3-deoxy-d-arabino-heptulosonate 7-phosphate (DAHP) synthase catalyze similar phosphoenolpyruvate-utilizing reactions. The genome of Neisseria gonorrhoeae contains one gene encoding KDOP synthase and one gene encoding DAHP synthase. Of the two nonhomologous DAHP synthase families known, the N. gonorrhoeae protein belongs to the family I assemblage. KDOP synthase exhibited an ability to replace arabinose-5-P with either erythrose-4-P or ribose-5-P as alternative substrates. The results of periodate oxidation studies suggested that the product formed by KDOP synthase with erythrose-4-P as the substrate was 3-deoxy-d-ribo-heptulosonate 7-P, an isomer of DAHP. As expected, this product was not utilized as a substrate by dehydroquinate synthase. The significance of the ability of KDOP synthase to substitute erythrose-4-P for arabinose-5-P is (i) recognition of the possibility that the KDOP synthase might otherwise be mistaken for a species of DAHP synthase and (ii) the possibility that the broad-specificity type of KDOP synthase might be a relatively vulnerable target for antimicrobial agents which mimic the normal substrates. An analysis of sequences in the database indicates that the family I group of DAHP synthase has a previously unrecognized membership which includes the KDOP synthases. The KDOP synthases fall into a subfamily grouping which includes a small group of DAHP synthases. Thus, family I DAHP synthases separate into two subfamilies, one of which includes the KDOP synthases. The two subfamilies appear to have diverged prior to the acquisition of allosteric-control mechanisms for DAHP synthases. These allosteric control specificities are highly diverse and correlate with the presence of N-terminal extensions which lack homology with one another.
An analysis of flow through sudden enlargements in pipes

An integral analysis of the type used to predict the flow of co-flowing jets has been applied to the problem of a sudden enlargement in a pipe (Borda–Carnot expansion). This technique successfully predicts all the overall flow parameters of interest (e.g. reattachment lengths, pressure profile, etc.). The analysis indicates that the downstream conditions (up to reattachment) are insensitive to wall shear and the point of minimum pressure does not coincide with the location of the maximum return-flow velocity.
Roots: Molecular basis of biological regulation: Origins from feedback inhibition and allostery

One observes regulation at every biological level. Organisms, cells, and biochemical processes operate efficiently, normally wasting neither material nor energy, and adjusting their functions to external influences. Nature evidently has evolved mechanisms specifically dedicated to regulation at many levels. What is the molecular basis of this control? In the 1950s these molecular control mechanisms began to be explored seriously. The discoveries of feedback inhibition of enzyme activity were important because they gave an initial example of how regulation is achieved at the molecular level. We showed that certain enzymes are composed of two parts, one for catalysis and another distinct part present only to regulate this catalysis. Catalytic activity can be either stimulated or inhibited when a small molecule in the environment combines with the enzyme's regulatory site. In particular, a final product of a metabolic pathway generates a feedback loop which automatically limits its own excessive production, by combining with the regulatory site of an early enzyme in that pathway. Later studies showed that catalytic and regulatory structures of some enzymes could be separated physically. The discovery of regulatory sites and their interaction with molecules unrelated to their substrates was the basis for the generalized allosteric concept. This concept extends the regulatory site idea to a wide variety of processes such as control of gene expression, hormone action, and cellular growth.
Boys will be boys; Cows will be cows: Children's essentialist reasoning about gender categories and animal species

Two studies (N = 456) compared the development of concepts of animal species and human gender, using a switched-at-birth reasoning task. Younger children (5- and 6-year-olds) treated animal species and human gender as equivalent; they made similar levels of category-based inferences and endorsed similar explanations for development in these 2 domains. In contrast, 10-year-olds and adults treated gender and species concepts as distinct from one another. They viewed gender-linked behavioral properties as open to environmental influence and endorsed environment-based mechanisms to explain gender development. At all ages, children demonstrated differentiated reasoning about physical and behavioral properties, although this differentiation became more stable with age. The role of psychological essentialism in guiding conceptual development is discussed.
Recent Developments in Kirchhoff Crack Tip Diffraction Correction

The Kirchhoff approximation is used extensively in modeling ultrasonic scattering by cracks, due to its conceptual simplicity and effectiveness in predicting scattering responses when the crack is favorably oriented. However, when the crack is unfavorably oriented, the Kirchhoff approximation can yield results with unacceptably large errors, due to an incomplete description of waves generated by diffraction at the crack tips. In such circumstances, it is desired to supplement Kirchhoff results with corrections that more accurately predict crack tip diffraction responses. One established means of obtaining such corrections is through application of the “geometrical theory of diffraction” (GTD). While the principles of GTD are appropriate for the problem at hand, implementation of these principles can be problematic when considering cracks with arbitrarily curved edges, due to local failings of various asymptotic assumptions. The goal of the work presented here is to develop a robust approach for applying the underlying principles of GTD to cracks having arbitrarily curved edges, suitable for implementation in an automated algorithm requiring no user intervention.
Integrating optical and electrical engineering courses

The expansion in the fields of optical engineering and optoelectronics has made it essential to introduce optical engineering concepts into undergraduate courses and curricula. Because of limits on the number of course requirements for the B.S. degree, it is not clear how these topics should be introduced without replacing some of the traditional requirements. This paper demonstrates how optical engineering concepts can be easily presented as an integral part of electrical engineering subjects, with a minimal amount of replacement, while enhancing the depth and understanding of both fields. Courses such as linear signals and systems, electricity and magnetism, and electronics which traditionally represent the core requirements of the undergraduate electrical engineering curriculum contain subjects that have direct correlations with optical engineering concepts. The major changes that are needed are the creation of textbooks that contain concepts and examples in areas of both optical and electrical engineering and some relearning and familiarization on the part of instructors. This approach allows for a fresh look at courses being offered in electrical engineering, while providing the necessary background in optical engineering for students.
Tissue engineering of heart valves: decellularized valve scaffolds.

In 1956, Gordon Murray first reported the human clinical surgical use of fresh aortic valve homografts (cadaveric) transplanted into the descending thoracic aorta for clinical amelioration of the consequences of native aortic valve insufficiency.1 His initial operation preceded by 5 years the availability of mechanical aortic valve prostheses. Although the operation was only partly successful hemodynamically, these “homograft valves” had remarkable durability and performance. Some patients had no calcification or transvalvular gradients for up to 20 years, whereas others ultimately failed as a consequence of progressive fibrosis and calcification.2,3⇓ In 1962, the initial use of aortic valve homografts in the orthotopic position were reported independently by Sir Donald Ross of England and Sir Brian Barrett-Boyes of New Zealand.4–6⇓⇓ As manufactured prosthetic valves gradually evolved in design and range of choices, homograft use began to decline because of issues of acquisitional logistics, banking, transport, sizing, infectious disease transmission, and others. With the development of organized organ and tissue donation for transplantation in the 1980s and 1990s, cardiovascular allograft tissues became increasingly available primarily as cryopreserved valves with variably retained native cell viability. Importantly, the terrific surgical and specific performance advantages of allograft semilunar cardiac valves have been recognized by reconstructive surgeons worldwide.7 These valve “transplants” have by and large crossed histocompatibility and ABO constraints, however. Although they perform well in the short- to mid-term, they have been associated with ultimate fibrosis and failure in a significant proportion of cases, especially in patients for whom the desirability of a living transplant would be the greatest: neonates, infants, and young children (ie, for whom retained growth and repair functions would be ideal). Thus, there have been many attempts to modify homograft valve transplants at either the donor or recipient level to achieve relative or actual immune …
Receptor-mediated Regulation of PI3Ks Confines PI(3,4,5)P3 to the Leading Edge of Chemotaxing Cells

Recent studies have demonstrated that PH domains specific for PI(3,4,5)P3 accumulate at the leading edge of a number of migrating cells and that PI3Ks and PTEN associate with the membrane at the front and back, respectively, of chemotaxing Dictyostelium discoideum cells. However, the dependence of chemoattractant induced changes in PI(3,4,5)P3 on PI3K and PTEN activities have not been defined. We find that bulk PI(3,4,5)P3 levels increase transiently upon chemoattractant stimulation, and the changes are greater and more prolonged in pten– cells. PI3K activation increases within 5 s of chemoattractant addition and then declines to a low level of activity identically in wild-type and pten– cells. Reconstitution of the PI3K activation profile can be achieved by mixing membranes from stimulated pi3k1–/pi3k2– cells with cytosolic PI3Ks from unstimulated cells. These studies show that significant control of chemotaxis occurs upstream of the PI3Ks and that regulation of the PI3Ks and PTEN cooperate to shape the temporal and spatial localization of PI(3,4,5)P3.
Explaining loss caused by tomato spotted wilt virus on tobacco with boreal winter weather: a Bayesian approach.

ABSTRACT In North Carolina, Tomato spotted wilt virus (TSWV) has regularly been reported since 1997, with incidence being the highest in 2002. At the end of each season, a questionnaire is sent to the county agents to report disease losses. TSWV reported losses in 1993 to 2007 from 58 counties were available. A county–year combination was considered a case and, in total, 494 cases were analyzed. The winter months' temperature and precipitation significantly explained the reported TSWV loss (R2 = 0.82). Specifically, the monthly average air temperature for December to February had a positive association with TSWV loss (P < 0.0001) whereas the total precipitation for the same months had a negative effect (P < 0.0001). Bayesian hierarchical models were implemented to include spatial and nonspatial random effects to investigate if there were significant spatial correlations or unexplained variability, respectively, and, thus, other significant variables that were ignored in the model development. The spatial ...
Home Builder Stocks in Mixed-Asset Portfolios

Executive Summary. The purpose of this study is to examine the long-run performance of homebuilder stocks and the potential role of the sector in institutional mixed-asset portfolios. Considering a...
Anoxic tolerance of beating and resting heart during perfusion at various temperatures.

SummaryHypothermia was produced in dogs by circulating, oxygenating and refrigerating venous blood in a small, plastic pump-oxygenator. The by-passed, contracting, hypothermic heart could be safely deprived of coronary flow for 15 minutes at 28°C and for at least 33 minutes at 20°C. During cardiac arrest induced by intracoronary injection of potassium citrate the safe period of myocardial ischemia could be prolonged to at least one hour at 20°C.