cssi/SciSciGPT-SciSciNet huggingface dataset:
Association of Midlife Hearing Impairment With Late-Life Temporal Lobe Volume Loss.

Importance Hearing impairment (HI) in midlife (45-65 years of age) may be associated with longitudinal neurodegeneration of temporal lobe structures, a biomarker of early Alzheimer disease. Objective To evaluate the association of midlife HI with brain volume trajectories in later life (≥65 years of age). Design, Setting, and Participants This prospective cohort study used data from the Baltimore Longitudinal Study of Aging to evaluate hearing from November 5, 1990, to October 3, 1994, and late-life volume change from July 10, 2008, to January 29, 2015, using magnetic resonance imaging (MRI) (mean follow-up time, 19.3 years). Data analysis was performed from September 22, 2017, to August 27, 2018. A total of 194 community-dwelling older adults who had midlife measures of peripheral hearing at a mean age of 54.5 years and late-life volume change of up to 6 years between the first and most recent MRI assessment were studied. Excluded were those with baseline cognitive impairment, stroke, head injuries, Parkinson disease, and bipolar disorder. Exposures Hearing as measured with pure tone audiometry in each ear from November 5, 1990, to October 3, 1994, and late-life temporal lobe volume change measured by MRI. Main Outcomes and Measures Linear mixed-effects models with random intercepts were used to examine the association of midlife hearing (pure tone average of 0.5-4 kHz tones in the better ear and each ear separately) with longitudinal late-life MRI-based measures of temporal lobe structures (hippocampus, entorhinal cortex, parahippocampal gyrus, and superior, middle, and inferior temporal gyri) in the left and right hemispheres, in addition to global and lobar regions, adjusting for baseline demographic characteristics (age, sex, subsequent cognitive impairment status, and educational level) and intracranial volume. Results A total of 194 patients (mean [SD] age at hearing assessment, 54.5 [10.0] years; 106 [54.6%] female; 169 [87.1%] white) participated in the study. After Bonferroni correction, poorer midlife hearing in the better ear was associated with steeper late-life volumetric declines in the right temporal gray matter (β = −0.113; 95% CI, −0.182 to −0.044), right hippocampus (β = −0.008; 95% CI, −0.012 to −0.004), and left entorhinal cortex (β = −0.009; 95% CI, −0.015 to −0.003). Poorer midlife hearing in the right ear was associated with steeper late-life volumetric declines in the right temporal gray matter (β = −0.136; 95% CI, −0.197 to −0.075), right hippocampus (β = −0.008; 95% CI, −0.012 to −0.004), and left entorhinal cortex (β = −0.009; 95% CI, −0.015 to −0.003), whereas there were no associations between poorer midlife hearing in the left ear with late-life volume loss. Conclusions and Relevance The findings suggest that midlife HI is a risk factor for temporal lobe volume loss. Poorer midlife hearing, particularly in the right ear, was associated with declines in hippocampus and entorhinal cortex.
Initial validation of the electronic form of the Michigan Body Map.

Background The Michigan Body Map (MBM) was developed to assess pain location in a reliable and valid manner; however, electronic formats have not been validated. This study had two aims: (1) initial validation of the electronic form of the MBM (eMBM) and (2) preliminary test of assessing pain severity within body zones. Methods For the first aim, 68 participants with chronic pain completed paper and electronic forms of the MBM, then underwent scripted interviews to assess preferences among body maps and verbal confirmation of pain locations. For the second aim, a subset of the participants (n=40) completed the Brief Pain Inventory (BPI) pain severity subscale, as well as the eMBM again and endorsed pain severity using additional screens showing body zones that contained areas in which pain was endorsed. Results There were few discrepancies between MBM, eMBM and verbal report (1.9% and 1.6%, respectively), and no difference between forms in perceived ability to indicate areas of pain or ease of completion. Patients accurately indicated their bodily pain on both maps, with 84% and 87% reporting one or no errors on MBM and eMBM, respectively. Participants also reported no preference for which version best-depicted areas of pain or best distinguished left from right. Lastly, the most preferred measure was eMBM with pain severity zones, followed by eMBM without zones, followed by the BPI pain severity subscale. Conclusions These data support the validity of the eMBM for patients with chronic pain. Further, an expanded form of the eMBM that assesses pain severity was preferred by most participants.
Backward Feature Correction: How Deep Learning Performs Deep Learning

How does a 110-layer ResNet learn a high-complexity classifier using relatively few training examples and short training time? We present a theory towards explaining this in terms of hierarchical learning. We refer hierarchical learning as the learner learns to represent a complicated target function by decomposing it into a sequence of simpler functions to reduce sample and time complexity. This paper formally analyzes how multi-layer neural networks can perform such hierarchical learning efficiently and automatically by applying SGD. On the conceptual side, we present, to the best of our knowledge, the FIRST theory result indicating how deep neural networks can be sample and time efficient on certain hierarchical learning tasks, when NO KNOWN non-hierarchical algorithms (such as kernel method, linear regression over feature mappings, tensor decomposition, sparse coding, and their simple combinations) are efficient. We establish a principle called "backward feature correction", where training higher layers in the network can improve the features of lower level ones. We believe this is the key to understand the deep learning process in multi-layer neural networks. On the technical side, we show for every input dimension $d > 0$, there is a concept class consisting of degree $\omega(1)$ multi-variate polynomials so that, using $\omega(1)$-layer neural networks as learners, SGD can learn any target function from this class in $\mathsf{poly}(d)$ time using $\mathsf{poly}(d)$ samples to any $\frac{1}{\mathsf{poly}(d)}$ error, through learning to represent it as a composition of $\omega(1)$ layers of quadratic functions. In contrast, we present lower bounds stating that several non-hierarchical learners, including any kernel methods, neural tangent kernels, must suffer from $d^{\omega(1)}$ sample or time complexity to learn this concept class even to $d^{-0.01}$ error.
A 38-Year-Old Woman with Baclofen Withdrawal

Intrathecal baclofen is an effective treatment for patients suffering from significant spasticity secondary to multiple sclerosis (MS). Intrathecal drug delivery systems (IDDS) are an effective way to deliver intrathecal baclofen safely; however, risks still exist. Increased spasticity in a patient with a baclofen IDDS needs to be worked up promptly for underlying disease modifiers as well as IDDS-related issues. IDDS-related issues include improper programming, incorrect drug concentration, catheter-related issues, and rotor failure. One should be vigilant for signs and symptoms of baclofen withdrawal and treat promptly to avoid serious sequelae including death. Current treatment for intrathecal baclofen withdrawal, including oral baclofen and use of benzodiazepines, is inadequate necessitating resumption of intrathecal therapy. Studies are ongoing to develop a safe intravenous (IV) formulation of baclofen. It is unclear how effective this will be in the treatment of intrathecal baclofen withdrawal.
The Impact of the Merge of Pfizer and Mylan Pharmaceuticals

First, in this deconstruction essay paper, the goal is to examine the acquisition and merger M&A of Pfizer Inc. (PFE) and Mylan, N.V. organizational relationships. Pfizer a famous global drug company known for their developing of product cures for erectile dysfunctions called ‘Viagra' as well as, globally recognized for the magic ‘blue pill' is one of the world's larger pharmaceutical firms in the world. Also, to focus on the economic model that will drive both Pfizer and Mylan's growth and investment in the organization's operations (internal growth). Next, the impact that this merger will have on the organization's size (external growth) that will be taken into consideration. Moreover, to deconstruct Mylan N.V. (MYL) global pharmaceutical company, specializing in the healthcare industry are they committed to raising the bar in manufacturing of high-quality medicine and will the combined forces of these two companies make a difference in the world of healthcare. Next, after they combine their products giving them a stronger pipeline to the public and private sector of the global healthcare industry will they survive?
Automated measurement of broiler stretching behaviors under four stocking densities via faster region-based convolutional neural network.

Abstract Stretching behavior is one of the broiler comfort behaviors that could be used for animal welfare assessment. However, there is currently no methodology for automatic monitoring of stretching behavior under representative production practices. The objectives of this study were to (1) develop a faster region-based convolutional neural network (faster R-CNN) stretching behavior detector for broiler stretching behavior detection, (2) evaluate broiler stretching behaviors under stocking densities (SDs) of 27 (27SD), 29 (29SD), 33 (33SD), and 39 kg/m2 (39SD) and at weeks 4 and 5 of bird ages, and (3) examine the temporal and spatial distribution of broiler stretching behaviors. The results show that the precision, recall, specificity, and accuracy were over 86% on broiler stretching detection across all SDs and bird ages using the faster R-CNN stretching behavior detector. Broilers spent 230–533 sec stretching every day and showed more stretching behaviors under the 29SD, 33SD, and 39SD in week 4 and under the 29SD and 33SD in week 5, as compared to other SDs. They performed less stretching in a couple of hours after light ON and before light OFF but preferred to stretch in areas with less traffic and disturbance, that is, along the fences and away from the inspection aisle. It is concluded that the stretching behavior detector had acceptable performance in detecting broiler stretching, thus being a useful tool for broiler stretching detection. Broiler stretching behavior is affected by SD and bird age and shows temporal and spatial variations.
Time-Driven Activity-based Costing for Anterior Cruciate Ligament Reconstruction: A Comparison to Traditional Accounting Methods

Purpose The primary purpose of this study was to compare the cost of care of one of the most common sports medicine surgical procedures, anterior cruciate ligament reconstruction (ACLR), using the time-driven activity-based costing (TDABC) method to traditional accounting methods such as activity-based costing (ABC). Our secondary purpose was to identify the main drivers of the cost of ACLR using both of these techniques. Methods A process map of ACLR was constructed through direct observation in the clinical setting according to established techniques to identify drivers of fixed, direct variable, and indirect costs. An episode of care consisted of each step in the surgical process from admission to discharge. Personnel costs were combined with the process map to determine the cost drivers and overall cost of the procedure. The cost generated from the TDABC method was compared with the cost from our institution’s internal accounting system, which used an ABC method. Results The total cost of ACLR was $5,242.25 when using TDABC versus $10,318 when using the traditional ABC method. The largest difference between the 2 methods was within the domain of direct variable costs. Conclusions When compared with TDABC, the hospital’s traditional cost-accounting estimate for ACLR is nearly twice as costly. These findings highlight the variability of cost calculation for the same clinical episode between the 2 accounting methods. For the traditional accounting method, the direct variable cost was the main cost driver, whereas for the TDABC method, the direct fixed cost was the main cost driver. Clinical Relevance This study is important because it elucidates important cost drivers for one of the most common sports medicine orthopaedic surgical procedures and attempts to identify the true overall cost of the procedure.
Inhibition of neprilysin with sacubitril without RAS blockage aggravates renal disease in Dahl SS rats.

Salt-sensitive (SS) hypertension is accompanied with severe cardiorenal complications. In this condition, elevated blood pressure (BP) resulting from salt retention is associated with counterintuit...
Privacy Policies and Practices with Cloud-Based Services in Public Libraries: An Exploratory Case of BiblioCommons

Public libraries are increasingly turning to cloud-based and Library 2.0 solutions to provide patrons more user-focused, interactive, and social platforms from which to explore and use library resources. These platforms – such as BiblioCommons – often rely on the collection and aggregation of patron data, and have the potential to disrupt longstanding ethical norms within librarianship dedicated to protecting patron privacy. This article reports on the results of a pilot research study investigating how libraries are implementing third-party cloud computing services, how these implementations might impact patron privacy, and how libraries are responding to these concerns. The results of this research provide insights to guide the development of a set of best practices for future implementations of cloud-based Library 2.0 platforms in public library settings.
Lipid metabolism in sickness and in health: Emerging regulators of lipotoxicity.

Summary Lipids play crucial roles in signal transduction, contribute to the structural integrity of cellular membranes, and regulate energy metabolism. Questions remain as to which lipid species maintain metabolic homeostasis and which disrupt essential cellular functions, leading to metabolic disorders. Here, we discuss recent advances in understanding lipid metabolism with a focus on catabolism, synthesis, and signaling. Technical advances, including functional genomics, metabolomics, lipidomics, lipid-protein interaction maps, and advances in mass spectrometry, have uncovered new ways to prioritize molecular mechanisms mediating lipid function. By reviewing what is known about the distinct effects of specific lipid species in physiological pathways, we provide a framework for understanding newly identified targets regulating lipid homeostasis with implications for ameliorating metabolic diseases.
Documentary Storytelling: Creative Nonfiction on Screen

Chapter 1 Introduction Part I Understanding Story Chapter 2 Story Basics Chapter 3 Finding the Story Chapter 4 Story Structure Chapter 5 Time on Screen Chapter 6 Creative Approach Chapter 7 Case Studies Part II Working with Story Chapter 8 Research Chapter 9 Planning Chapter 10 Selling Chapter 11 Shooting Chapter 12 Editing Chapter 13 Narration and Voice Over Chapter 14 Storytelling: A Checklist Part III Talking about Story Chapter 15 Steven Ascher and Jeanne Jordan Chapter 16 Victoria Bruce and Karin Hayes Chapter 17 Ric Burns Chapter 19 Brett Culp Chapter 20 Alex Gibney Chapter 21 Susan Kim Chapter 22 James Marsh Chapter 23 Sam Pollard Chapter 24 Deborah Scranton Part IV Additional Material Sources and Notes Films About the Author Index
Microfabrication Technology for Chemical and Biochemical Microprocessors

We have developed two key technologies necessary for the fabrication of fully-integrated DNA analysis microprocessors. Submicroliter PCR reactors directly coupled to separation microchannels provide integrated DNA amplification and capillary electrophoresis analysis. Novel microchannel turn geometries for the fabrication of folded separation channels provide increased device performance and feature density.
Buyer Beware: Electronic Letters of Credit and the Need for Default Rules

V. THE EUCP: PROBLEMS AND SOLUTIONS 391 A. Presentation 392 1. Current eUCP Article e5 and e11 392 2. Problems with Current Articles e5 and e11 392 3. Proposed Amendment to Article e11 394 B. Agreement on Formatting 395 1. Current eUCP Article e4 395 2. Problems with Current Article e4 395 3. Proposed Amendment to Article e4 396 4. Documents Transmitted by a Third Party 397 a. Current eUCP Article e5 397 b. Problems with Current Article e5 398 c. Proposed Amendment to Article e5 398 5. Evidentiary Treatment of Electronic Records 400 a. The Problem with the Current eUCP 400 b. Proposed Amendment to the eUCP 401
Anthocyanidins and related compounds. XV. The effects of sunlight on flavylium salt-chalcone equilibrium in acid solutions.

Abstract The position of the equilibrium between flavylium salts and 2-hydroxychalcones in aqueous solutions is markedly effected by light. NMR and UV spectral data indicate that the chalcones formed at equilibrium have the trans -configuration. In sunlight these photoisomerize rapidly to cis 2-hydroxychalcones, which then cyclize in acid solutions to flavylium salts. In the absence of light the necessary, initial trans to cis isomerization is acid catalyzed and occurs readily only with-those chalcones with stabilizing, electron-donating groups, e.g. methoxyl, at the 4 and/or 6 positions. Prolonged exposure of cis 2-methoxychalcones to light results in a photochemical demethylation with formation of the cis 2-hydroxychalcone or cyclic pseudo base.
The Past and Future of Network Analysis in Economics

This is a short essay offering some perspective on the literature on networks in economics.
Platypnea-Orthodeoxia Syndrome in Two Previously Healthy Adults: A Case-based Review:

We describe here the clinical manifestations of platypnea-orthodeoxia in two patients with interatrial shunting. In both cases, the patients were asymptomatic prior to developing additional cardiopulmonary issues that apparently enhanced right-to-left intracardiac shunting. The patients were both treated with percutaneously deployed occlusion devices, with excellent results. Symptoms and positional oxygen desaturation resolved after device placement in both cases. In addition, these patients remain symptom-free 30 months after device implantation.
Social Cognition: Some Historical and Theoretical Perspectives

Publisher Summary Social cognition is established to serve as a new forum for the ever increasing numbers of investigations. This chapter examines the current theories of social cognition and the intellectual history out of which social cognition has arisen. It also reveals the pervasive and continuing influence of two generic traditions within psychology: associationism and constructionism. It is salutary in the development of social cognition to explore its intellectual history, its associationist, and its constructionist traditions to address the question of whether or not social cognition represents an important theoretical advance. In the chapter, the roots of associationism as well as its present application in social cognition research and the roots of constructionism and its present application in social cognition research are also explored. The central concerns of cognitive psychology are representation and processing. These issues require the building and testing of theoretical constructs and models. The formation or processing of representations is directly observed and introspection regarding cognitive processes is problematic. The chapter also focuses on those investigations of social cognition that explicitly apply associationist or constructionist theory.
Deployment of Air Bags into the Thorax of an Out-of-Position Dummy

The air bag has proven effective in reducing fatalities in frontal crashes with estimated decreases ranging from 11% to 30% depending on the size of the vehicle. At the same time, some air bag designs have caused fatalities when front-seat passengers have been in close proximity to the deploying air bag. The objective of this study was to develop an accurate and repeatable out-of-position test fixture to study the deployment of air bags into out-of-position occupants. Tests were performed with a fifth percentile female Hybrid III dummy and studied air bag loading on the thorax using draft ISO-2 out-of-position occupant positioning. All tests were performed in one of four nominal positions with respect to the steering wheel plane using a production depowered air bag from the current automobile fleet. Dummy positioning on the test fixture was found to be repeatable to within 0.3 cm on all axes. This variation was within the dimensional similarity of the two available fifth percentile female Hybrid III dummies. A large variation in occupant response was found with a very small change in effective distance from the sternum to the air bag module. Nearly 50% variation in peak chest center-of-gravity resultant acceleration was found when moving from the sternum pressed on the air bag module to the sternum effectively being 2 cm from the module. In addition, large variations in occupant response were found with vertical and horizontal displacements of the occupant with respect to the air bag module center. Also, a qualitative change in air bag deployment was found on changing the horizontal position by 4 cm to the left. These variations have significant implications for expected response from in-vehicle out-of-position dummy tests.
A Risk-Averse Optimization Model for Unit Commitment Problems

In this paper, we consider the unit commitment problem of a power system with high penetration of renewable energy. The optimal day-ahead scheduling of the system is formulated as a risk-averse stochastic optimization model in which the load balance of the system is satisfied with a high prescribed probability level. In order to handle the ambiguous joint probability distribution of the renewable generation, the feasible set of the optimization problem is approximated by an quantile-based uncertainty set. Results highlight the importance of large sample size in providing reliable solutions to the SCUC problems. The method is flexible in allowing a range of risk into the problem from higher-risk to robust solutions. The results of these comparisons show that the higher cost of robust methods may not be necessary or efficient. Numerical results on a test network show that the approach provides significant scalability for the stochastic problem, allowing the use of very large sample sets to represent uncertainty in a comprehensive way. This provides significant promise for scaling to larger networks because the separation between the stochastic and the mixed-integer problem avoids multiplicative scaling of the dimension that is prevalent in traditional two-stage stochastic programming methods.
Influence of Irradiation on the Tensile Properties of the Aluminum Alloy 6061

It has been shown that the aluminum alloy 6061 in the fully annealed, cold-worked, and age-hardened conditions undergoes very small changes in the tensile properties as a result of neutron irradiation to doses on the order of 1019 fast n/cm2( > 2.9 MeV) and 1020 thermal n/cm2. At irradiation temperatures above 115°C, no changes in properties are observed. The small property changes observed when the material is irradiated at 43°C are mostly annealed out after ½ h at 200°C. These changes are rationalized in terms of the precipitate particles present in the alloy and the mobility of the irradiation-induced defects.
Activation of EphA receptor tyrosine kinase inhibits the Ras/MAPK pathway

Interactions between Eph receptor tyrosine kinases (RTKs) and membrane-anchored ephrin ligands critically regulate axon pathfinding and development of the cardiovascular system, as well as migration of neural cells. Similar to other RTKs, ligand-activated Eph kinases recruit multiple signalling and adaptor proteins, several of which are involved in growth regulation. However, in contrast to other RTKs, activation of Eph receptors fails to promote cell proliferation or to transform rodent fibroblasts, indicating that Eph kinases may initiate signalling pathways that are distinct from those transmitted by other RTKs. Here we show that stimulation of endogenous EphA kinases with ephrin-A1 potently inhibits the Ras/MAPK cascade in a range of cell types, and attenuates activation of mitogen-activated protein kinase (MAPK) by receptors for platelet-derived growth factor (PDGF), epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF). In prostatic epithelial cells and endothelial cells, but not fibroblasts, treatment with ephrin-A1 inhibits cell proliferation. Our results identify EphA kinases as negative regulators of the Ras/MAPK pathway that exert anti-mitogenic functions in a cell-type-specific manner.
Two Simple Algorithms for Refining Mammalian Receptor Selection in Ecological Risk Assessments

Although guidelines exist for selecting appropriate ecological receptors for risk assessments at contaminated sites, it can be demonstrated that many of the mammals commonly evaluated are spatially irrelevant. Terrestrial risk assessments could be simplified and made more efficient, though, if mammals that are initially considered were screened for their spatial relevance. This article presents 2 simple algorithms that each demonstrate that most mammalian receptors are not spatially relevant for the overwhelming majority of hazardous waste and other contaminated sites. The algorithms use readily available and curiously overlooked spatial distribution (e.g., animal density) information and suggest that contaminated sites need to be 80 to 100 acres in size to justify the inclusion of most mammalian receptors. Given that hazardous waste sites are generally much smaller than this, many ecological risk assessments (ERA) could reasonably dispense with incorporating mammals entirely. An awareness on the part of decision makers and risk managers of the nonsuitability of many mammalian receptors evaluated in terrestrial ERAs could significantly impact the perceived need to monitor or remediate sites. This article also examines the anticipated challenges of regulators and other decision makers when entertaining the notion of a spatial relevance screen for mammals.
The neurobiology of pain perception in normal and persistent pain

SUMMARY Pain is a significant national burden in terms of patient suffering, expenditure and lost productivity. Understanding pain is fundamental to improving evaluation, treatment and innovation in the management of acute and persistent pain syndromes. Pain perception begins in the periphery, and then ascends in several tracts, relaying at different levels. Pain signals arrive in the thalamus and midbrain structures which form the pain neuromatrix, a constantly shifting set of networks and connections that determine conscious perception. Several cortical regions become active simultaneously during pain perception; activity in the cortical pain matrix evolves over time to produce a complex pain perception network. Dysfunction at any level has the potential to produce unregulated, persistent pain.
Chemical Abstracts' document delivery service

In the Spring of 1981, Chemical Abstracts joined the growing number of commercial vendors who offer document delivery services. Chemical Abstracts is a welcome entry into this market place by providing many soviet publications, various patents from a variety of countries, and most materials cited by CA in their indexes within the last ten years. While their rates are not inexpensive, Chemical Abstracts' Document Delivery Service is a valuable resource for materials which are not readily available from other sources. The purpose of this article is to describe Chemical Abstracts' Document Delivery Service in terms of DIALORDER, the mail, and OCLC. Included in this article are transmission costs, success rates, delivery times, and other considerations involved in utilizing CA's Document Delivery Service.
The Recent Magnetic Storm and Aurora

THE aurora of Monday, the 2nd instant, was succeeded by another on the following night at 11 p.m. It assumed the form of pale streamers issuing from a point in the horizon about north by east, and uniting in a similar way directly opposite in the south, like the meridian lines marked on a globe. The streamer crossing the zenith was the brightest.
Orthography and identity in Cameroon

The tone languages of sub-Saharan Africa raise challenging questions for the design of new writing systems. Marking too much or too little tone can have grave consequences for the usability of an orthography. Orthography development, past and present, rests on many sociolinguistic issues having little to do with the technical phonological concerns that usually preoccupy orthographers. Some of these issues are familiar from the spelling reforms which have taken place in European languages. However, many of the issues faced in sub-Saharan Africa are different, being concerned with the creation of new writing systems in a multi-ethnic context — involving residual colonial influences, the construction of new nation-states, detribalization vs. culture preservation and language reclamation. Language development projects which crucially rely on creating or revising orthographies may founder if they do not attend to the various layers of identity (colonial, national, ethnic, local, or individual) that are indexed by orthography. This study reviews the history and politics of orthography in Cameroon, with a focus on tone-marking. The article concludes by calling present-day orthographers to a deeper and broader understanding of orthographic issues.
Incompressible quantum Hall states.

Considering each electron as a superposition of fictitious fractionally charged particles allows, with the help of a natural ansatz, a systematic identification and characterization of the incompressible quantum Hall states at noninteger filling factors. Explicit Laughlin-type wave functions are obtained for all the incompressible states and their quasiparticles. The order of stability of the various states predicted on the basis of physically plausible rules is in agreement with experiments. Although in principle all rational fractions are observable, these rules imply that the even-denominator fractions are in general much less stable than the odd-denominator ones.
Reconstruction of histograms of the glass transition temperature of free radical copolymers from DSC thermograms

Most polymeric materials appear as complex mixtures of macromolecules characterized by distributions of specific properties that are essential to the quality of these products. Among such properties, the accurate determination of the glass transition temperature, and therefore, accurate representation of it, is a key issue. When analyzed using dynamic scanning calorimetry (DSC) techniques, many copolymers exhibit a wide range of temperature over which the glass transition takes place, and the width of the transition region is, therefore, not satisfactorily described by average Tg values, for example those computed from tangent curves drawn on thermograms. This article describes a method that allows us to characterize this spreading of the glass transition region by reconstructing weighted Tg distributions from DSC thermograms. As such an objective might appear as questionable from a strictly physical point of view, the significance of what is meant by “distribution” is specified in the text. A model is proposed that accounts for relaxation phenomena. The approach is validated by examining samples of BuA/Sty emulsion copolymers produced at different overall conversions and compositions, and examining the corresponding histograms of Tg were computed. The results show that accurate and consistent information on the glass transition behavior of the copolymer is obtained, and that the effective distribution is clearly connected with the composition drift in the polymer particles. The proposed algorithm allows one to obtain a maximum amount of information from DSC measurements, and provides a deeper insight into the “history” of complex polymer mixtures. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 357–367, 2000
Single electron tunneling and manipulation of nanoparticles on surfaces at room temperature

This article focuses on surfaces containing nanoparticles and self-assembled monolayers (SAMs). These surfaces provide a simple and reliable platform for measurements of single electron tunneling (SET) properties of metal nanoparticles at room temperature. This approach of interfacial chemistry allows for the elimination of lateral motion of the individual nanoparticles during electronic property studies. The scanning tunneling microscopy (STM) in ultra-high vacuum is used as an accurate and reproducible probe for imaging and I–V characterization of individual or aggregated Au nanoparticles, revealing a large Coulomb gap (1.0 eV) and fine Coulomb staircases (0.2–0.3 eV) at room temperature. The surrounding decanethiol SAM provides an ideal reference for the imaging and I–V measurements of nanoparticles. These measurements provide a quantitative guide for regulating current and voltage, at which individual Au nanoparticles may be detached and manipulated with the STM tip.
Differential LHRH Secretion, Dye Coupling, and Protein Expression in Two Morphologically Distinct Cell Types Identified in GT1–7 Cultures

The immortalized neuronal cell line, GT1-7, has been shown to secrete LHRH in a pulsatile manner and to possess many other characteristics of hypothalamic LHRH neurons in vivo, and thus provides a potential model system for studying biochemical and physiological mechanisms regulating LHRH secretion. In the present study, two morphologically and functionally distinct types of cells have been identified in GT1-7 cultures and each type purified to over 95% homogeneity. One type (N cells) appeared more neuronal with extended neurites and somewhat rounded cell perikarya, while the other type (G cells) had flatter cell perikarya that contained filopodia but no neurites. Growth properties of the two cell types also differed. The doubling time for proliferation of N cells was nearly two-fold shorter than that for G cells and N cells displayed 'piling up' whereas G cells exhibited contact inhibition. Functionally, N cells, but not G cells, were dye-coupled as measured by a fluorescence photobleaching assay. While both cell types expressed LHRH, N cells released significantly higher levels of LHRH into the culture media and exhibited more intense LHRH immunostaining. The two cell types also showed differences in immunostaining for other proteins. N cells, unlike G cells, immunostained positive for neuron-specific enolase (NSE), whereas G cells, unlike N cells, stained immunopositive for vimentin. Both cell types expressed SV-40 T antigen protein, indicating that they were derived from the same transgenic mouse hypothalamic tumour. The physiological significance of these two cell types in GT1-7 cultures remains to be determined, but elucidation of their morphological and biochemical properties is intended to contribute to better understanding and application of this experimentally important neuroendocrine cell line.
Contribution of the magnetic dipole transition in the Be isoelectronic sequence

Abstract The 1s22s2p J = 2 → J = 1 M1 transition rates are calculated in the multi-configuration Hartree-Fock procedure for several members of the beryllium isoelectronic sequence. The total transition rates, including existing M2 rates, are presented for different atomic numbers.
Esophageal Obstruction due to Intermuscular Hematoma following Pneumatic Dilatation

A case of incomplete esophageal perforation with an intermuscular hematoma is presented. Unlike previously described submucosal or intramural perforations, this case involved mucosa, submucosa, and the inner circular muscle layer but was limited by the outer longitudinal layer. Nonsurgical treatment was followed when the clinical picture of an incomplete perforation without mediastinal soilage was considered. Surgery was done when evidence of impending extension of the process outside the esophagus developed.
Fabrication of resonator-quantum well infrared photodetector test devices and focal plane arrays

Resonator-Quantum Well Infrared Photodetectors (R-QWIPs) are the next generation of QWIP detectors that use resonances to increase the quantum efficiency (QE). To achieve the expected performance, the detector geometry must be produced in precise specification. In particular, the height of the diffractive elements (DE) and the thickness of the active resonator must be uniformly and accurately realized to within 0.05 μm accuracy and the substrates of the detectors have to be removed totally. To achieve these specifications, two optimized inductively coupled plasma (ICP) etching processes are developed. Using these etching techniques, we have fabricated a number of R-QWIP test detectors and FPAs with the required dimensions and completely removed their substrates. The QE spectra were tested to be in close agreement with the theoretical predictions. The operability and spectral uniformity of the focal plane array (FPA) is about 99.1% and 3% respectively.
Structural basis of differences in isoform-specific gating and lidocaine block between cardiac and skeletal muscle sodium channels.

Voltage-gated Na + channels underlie rapid conduction in heart and skeletal muscle. Cardiac sodium channels open and close over more negative potentials than do skeletal muscle sodium channels; heart channels are also more sensitive to lidocaine block. The structural basis of these differences is poorly understood. We mutated nine isoform-specific μ1 (rat skeletal muscle) channel residues in domain IV to those at equivalent locations in hH1 (human cardiac) channels. Channel constructs were expressed in tsA-201 cells and screened for changes in gating and lidocaine sensitivity. Only L1373E, located in the linker between the S1 and S2 transmembrane segments, shifted activation gating and use-dependent block by lidocaine toward that seen in hH1. The converse mutation, hH1-E1555L, shifted the phenotype of hH1 to resemble that of μ1. Therefore, we identified a previously unsuspected glutamate-to-leucine isoform-specific variant site (i.e., 1555 in hH1 and 1373 in μ1) that significantly influences gating and drug block in sodium channels. The identification of the residue at this position plays a major role in shaping the responses of sodium channels to voltage and to lidocaine, helping to rationalize the distinctive behavior of cardiac sodium channels.
Effect of fibrillation on the secretion of acetylcholinesterase from cultured embryonic rat myotubes.

Abstract We have measured acetylcholinesterase (AChE) turnover and secretion in spontaneously fibrillating rat myotubes and in cultures in which fibrillation was blocked with tetrodotoxin. The rat at which AChE appeared in the medium was 4 times greater in fibrillating than in non-fibrillating cultures. In a 2-h interval, 32% of the AChE in fibrillating myotubes and 26% of the AChE in non-fibrillating myotubes turned over. In this interval, secreted AChE accounted for 28% and 16% of the AChE turnover that occurred in fibrillating and non-fibrillating myotubes, respectively.
Hydrogen isotope effects in the in vivo utilization of formate.

Abstract The hydrogen isotope effects in the utilization of formate in the rat were investigated with formate labeled intermolecularly with deuterium, tritium, and C 14 . Following the administration of this triply labeled formate, the isotope ratios of the formate excreted in the urine and of the methyl groups of tissue choline and creatine were determined and compared with the same ratios in the injected formate. The results indicate extensive selection among the hydrogen isotopes during the metabolism of formate. Intramolecular multiple labeling is suggested as a means of allowing less equivocal interpretations of isotope ratios in studies of the metabolism of C-H units.
Effects of dietary lipid and reduced glutathione on composition and storage quality of channel catfish, Ictalurus punctatus (Rafinesque)

. Semi-purified casein/gelatin diets containing two levels of lipid (5 or 10%) and three levels of reduced glutathione (0,0·1 or 1·0%) in a factorial arrangement were fed to fingerling channel catfish, Ictalurus punctatus (Rafinesque), in aquaria for 10 weeks. Factorial analysis of variance indicated that dietary lipid had significant (P < 0·05) effects on growth, feed efficiency and body composition of channel catfish. Diets containing 10% lipid generally produced higher weight gain and feed efficiency values as well as higher intraperitoneal fat. The higher level of dietary lipid also produced lower moisture and higher lipid (on a wet-weight basis) levels in whole-body and fillet tissues. Stability of fillet samples was estimated by 2-thiobarbituric acid (TBA) analysis which revealed that 10% dietary lipid significantly elevated fillet TBA values while glutathione did not have any effect. Therefore, dietary lipid level altered growth and body composition of channel catfish as well as oxidative stability of fillet samples while dietary glutathione was generally ineffective.
An examination of relational-interdependent self-construal, communal strength, and pro-relationship behaviors in friendships

Individual differences in relational-interdependent self-construal (RISC) are associated with positive relationship characteristics. This suggests that RISC is positively associated with the degree to which individuals view their relationships as communally-oriented (i.e., governed by norms of responsiveness), which should in turn be associated with increased use of pro-relationship behaviors. Thus, the current study explored the associations between RISC, communal strength, and pro-relationship behaviors in friendships. As predicted, RISC was positively associated with pro-relationship behavior use, but this association was mediated by greater communal strength. This suggests that increased RISC is associated with greater relationship satisfaction because the manner in which individuals view their relationships (i.e., communally) explains the association between RISC and constructive relationship behavior.
A derivative-based bracketing scheme for univariate minimization and the conjugate gradient method

Abstract A derivative-based scheme for univariate minimization is developed. This scheme has a quadratic convergence rate and requires an evaluation of the function and its derivative in each iteration. An application involving the conjugate gradient method is presented.
Synthesis of Atomically Ordered AuCu and AuCu3 Nanocrystals from Bimetallic Nanoparticle Precursors

A new multistep approach was developed to synthesize atomically ordered intermetallic nanocrystals, using AuCu and AuCu(3) as model systems. Bimetallic nanoparticle aggregates are used as precursors to atomically ordered nanocrystals, both to precisely define the stoichiometry of the final product and to ensure that atomic-scale diffusion distances lower the reaction temperatures to prevent sintering. In a typical synthesis, PVP-stabilized Au-Cu nanoparticle aggregates synthesized by borohydride reduction are collected by centrifugation and annealed in powder form. At temperatures below 175 degrees C, diffusion of Cu into Au occurs, and the atomically disordered solid solution Cu(x)Au(1)(-)(x) exists. For AuCu, nucleation occurs by 200 degrees C, and atomically ordered AuCu exists between 200 and 400 degrees C. For AuCu(3), an AuCu intermediate nucleates at 200 degrees C, and further diffusion of Cu into the AuCu intermediate at 300 degrees C nucleates AuCu(3). Atomically ordered AuCu and AuCu(3) nanocrystals can be redispersed as discrete colloids in solution after annealing between 200 and 300 degrees C.
On the Primacy of Writing in French: The Primacy of Speech

author appreciates the fact that the more one learns of the language of a people, the less and less "savage" the citizens of that culture appear as time goes on. Each of you who is responsible for a language laboratory or produces the material to be used therein has the direct responsibility of recognizing defects in the materials your students will use. Only by constant vigil in this area will the less satisfactory materials eventually disappear from the scene, to be replaced by more examples of those few excellent courses now available. ALBERT VALDMAN
Summertime moisture divergence over the southwestern US and northwestern Mexico

This paper investigates large-scale summertime moisture divergence associated with the southwestern branch of the North American monsoon. Diagnostic hydrologic estimates taken from thirty-three years of seasonal mean reanalysis data indicate that over most of the southwestern United States and northwestern Mexico there is positive vertically-integrated columnar (i.e. three dimensional) moisture divergence above approximately 700 mbar, implicitly suggesting that mid-level moisture convergence related to advection from remote source regions cannot support seasonal mean precipitation over the southwestern US. Furthermore, estimates of the horizontal component of this moisture divergence indicate that the southwestern US is actually one of the largest upper-air (<700 mbar) sources of moisture for the North American continent.
Trace elements in soil and biota in confined disposal facilities for dredged material.

Abstract We studied the relation of trace element concentrations in soil to those in house mice (Mus musculus), common reed (Phragmites australis) and ladybugs (Coccinella septempunctata at five disposal facilities for dredged material. The sites had a wide range of soil trace element concentrations, acid soils and a depauperate fauna. They were very poor wildlife habitat because they were dominated by the common reed. Bioassay earthworms exposed to surface soils from three of the five sites died, whereas those exposed to four of five soils collected a meter deep survived, presumably because the deeper, unoxidized soil, was not as acid. Concentrations of Ni and Cr in the biota from each of the sites did not seem to be related to the concentrations of the same elements in soil. Although Pb, Zn and Cu concentrations in biota were correlated with those in soil, the range of concentrations in the biota was quite small compared to that in soil. The concentrations of Pb detected in mice were about as high as the concentrations previously reported in control mice from other studies. Mice from the most contaminated site (530 ppm Pb in soil) contained only slighly more Pb (8 ppm dry wt) than did mice (2–6 ppm dry wt) from sites containing much less Pb (22–92 ppm in soil). Despite the acid soil conditions, very little Cd was incorporated into food chains. Rather, Cd was leaching from the surface soil. We concluded that even the relatively high concentrations of trace elements in the acid dredged material studied did not cause high concentrations of trace elements in the biota.
Integrated passive front-ends for towed decoys

The emergence of millimeter wave technologies operating at frequencies outside of traditional electronic warfare bands has been noticed. A critical component of electronic warfare is the towed decoy, which protects its platform from radar guided missiles. The autonomous decoy operates by receiving signals and then emitting appropriate counter-signals to suppress, deceive and/or seduce missiles. Key design features for this platform include wide bandwidth, dual polarization, high power capability, high directivity, low dispersion, low cost and reduced size.
Five years of experience with electric response audiometry.

The results from electric response audiometry (ERA) tests of 83 persons, including experimental subjects (those whose hearing thresholds were known) and clinical subjects between the ages of one mo...