cssi/SciSciGPT-SciSciNet huggingface dataset:
Ultra-Stable Integrated Lasers and Low-Cost, Low-Energy Coherent Data Center Interconnect

As data center ethernet switches scale towards 100Tbps, fiber links that keep pace with interconnecting exploding DCI capacity will face significant cost, power and engineering barriers. In this talk, we describe FRESCO, an approach to bring highly coherent WDM Terabit links inside the data center without the need for DSPs and other power consuming technologies. FRESCO is based on photonic integrated ultra-stable, ultra-low linewidth shared laser, optical frequency comb and silicon photonic transceiver technologies.
Post-traumatic bilateral blindness in a toddler

Abstract A unique case of vision loss in a two-year-old boy after sustaining a head injury as a pedestrian versus car was seen at our paediatric trauma unit. A CT brain was negative for fracture, intra-cranial haemorrhage and contusion. There were no neurological symptoms and no signs of abuse. Ophthalmological examination demonstrated retinal haemorrhages, cotton wool spots and Purtscher flecken that are pathognomonic for the diagnosis of Purtscher's retinopathy. This occlusive microvasculopathy, associated with cranial and chest trauma, may cause severe blindness. In literature, bilaterality was described in almost two thirds of cases. Regardless of management with or without medication, visual function improved in the majority of cases. In our case, despite treatment with high-dose intravenous methylprednisolone, the child's vision remained poor with bilateral optic atrophy and retinal pigmentary changes. Children with Purtscher's retinopathy should be examined for signs of non-accidental injury.
Formative Assessment Methods for Middle Level Classrooms

Formative assessment is the process of gathering student data during instruction, so teachers can make adjustments to facilitate student learning. Despite the benefits of formative assessment for t...
A non-parametric investigation of supply side factors and healthcare efficiency in the U.S

In this study, the supply-side factors affecting healthcare efficiency in the U.S are studied using data between 2010 and 2017. The recently developed non-parametric order-m estimator is used for the analysis. Results suggest that the U.S. has output production that is 87.6-percent of the expected maximum amount, with life expectancy being 3 years too short given healthcare spending and education levels. However, conditioning efficiency estimates on supply-side secondary environmental variables explains 34 to 85-percent of inefficiency found in the average county. This suggests that hospital expenditures are an inefficient mechanism to improve healthcare efficiency, while focus should be placed on the number and composition of healthcare personnel. Our results suggest that lack of access to care due to provider availability is the biggest impediment to timely and successful care, and that increasing the number of primary care providers or nurse practitioners will improve poor health outcomes in many counties. This suggests that healthcare providers are the main avenues to improve healthcare inefficiency on the supply side.
Available Therapies for Patients with Neurofibromatosis-Related Nervous System Tumors

Though the majority of nervous system tumors are sporadic, several clinically relevant genetic syndromes are associated with a predisposition to tumors of the central and peripheral nervous system including neurofibromatosis type 1 (NF1), type 2 (NF2), and schwannomatosis (SWN). These represent prototypical tumor suppressor syndromes where loss of a tumor suppressor gene-protein impairs the cell’s ability to regulate cell proliferation. While clinical manifestations vary widely for each of these syndromes, tumors arising in the peripheral nerve sheath are a unifying feature. Clinical clues should prompt the clinician to recognize the underlying genetic syndrome and screen for associated tumors including, among others, plexiform neurofibromas and gliomas in NF1 and vestibular schwannomas, meningiomas, and spinal ependymomas in NF2. Improvements in mechanistic understanding of how the genetic mutations that underlie these syndromes contribute to tumor formation have led to new advances in targeted therapies. MEK inhibitors have shown promise for treating progressive plexiform neurofibromas in NF1. Bevacizumab has been shown to improve hearing and treat vestibular schwannomas in NF2. This article reviews the currently available data on management of tumors associated with these three syndromes.
GDNF synthesis, signaling, and retrograde transport in motor neurons.

Glial cell line–derived neurotrophic factor (GDNF) is a 134 amino acid protein belonging in the GDNF family ligands (GFLs). GDNF was originally isolated from rat glial cell lines and identified as a neurotrophic factor with the ability to promote dopamine uptake within midbrain dopaminergic neurons. Since its discovery, the potential neuroprotective effects of GDNF have been researched extensively, and the effect of GDNF on motor neurons will be discussed herein. Similar to other members of the TGF-β superfamily, GDNF is first synthesized as a precursor protein (pro-GDNF). After a series of protein cleavage and processing, the 211 amino acid pro-GDNF is finally converted into the active and mature form of GDNF. GDNF has the ability to trigger receptor tyrosine kinase RET phosphorylation, whose downstream effects have been found to promote neuronal health and survival. The binding of GDNF to its receptors triggers several intracellular signaling pathways which play roles in promoting the development, survival, and maintenance of neuron-neuron and neuron-target tissue interactions. The synthesis and regulation of GDNF have been shown to be altered in many diseases, aging, exercise, and addiction. The neuroprotective effects of GDNF may be used to develop treatments and therapies to ameliorate neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). In this review, we provide a detailed discussion of the general roles of GDNF and its production, delivery, secretion, and neuroprotective effects on motor neurons within the mammalian neuromuscular system.
Gratitude Reduces Consumption of Depleting Resources

Sustaining finite public resources presents a dilemma between acting in self-interest for present benefit versus working toward long-term collective gain. Given gratitude's links to prosociality and self-control, the present studies investigated whether gratitude would promote sustainable resource extraction under conditions of rapidly depleting resources. In Study 1 (N = 155), participants were randomly assigned to experience an emotional state (gratitude or neutral) prior to playing a resource dilemma game in which the common pool was manipulated to indicate either a sustained or depleting resource status. Neutral participants increased their point taking when the pool was depleting compared with when it was sustained; however, this pattern was not observed for grateful participants. Study 2 (N = 224) replicated these findings while also showing the effect of gratitude to be distinct from happiness. These findings show that gratitude, as opposed to a general positive emotional state, buffers against overtaking in resource dilemmas and suggests that this emotion may be useful in promoting sustainable behavior. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
“Being There” vs “Being Direct:” Perspectives of Persons with Serious Mental Illness on Receiving Support with Physical Health from Peer and Non-Peer Providers

Individuals with serious mental illness (SMI) face significant health disparities and multiple barriers to engaging in health behavior change. To reduce these health disparities, it is necessary to enhance the support individuals with SMI receive through the collaboration of different healthcare providers. This study explored how people with SMI living in supportive housing perceived receiving support from peer and non-peer providers for their physical health. Qualitative interviews were conducted with 28 participants receiving a peer-led healthy lifestyle intervention in the context of a randomized trial in supportive housing agencies. Interviews explored participants' experiences working with the healthy lifestyle peer specialist and a non-peer provider who assisted them with health. Interviews were audio recorded, transcribed, and analyzed using strategies rooted in grounded theory. Participants viewed their relationships with peer and non-peer providers positively, but described differences in the approach to practice, power dynamics present, and how they identified with each provider. Participants described peers as process-oriented while non-peer staff as task-oriented, focusing on accomplishing concrete objectives. Each provider sought to boost participants' motivation, but peers built hope by emphasizing the possibility of change, while non-peer providers emphasized the consequences of inaction. Participants related to peer staff through shared experiences, while identifying the importance of having a shared treatment goal with their non-peer provider. Overall, participants appreciated the unique roles of both peer and non-peer staff in supporting their health. Study findings have implications for integrating the use of peer-based health interventions to improve the health of people with SMI.
"If We Turned Our Backs, They Would Ignore Our Wishes": Bereaved Family Perceptions of Concordance of Care at the End of Life.

Background: The key to high-quality care at the end of life is goal-concordant care, defined as care that is consistent with patient wishes. Objectives: To characterize decedent wishes for care at ...
A Survey on Deep Learning for Intracranial Hemorrhage Detection

Computed Tomography (CT) images of the patient’s cranium are widely used in the diagnosis of hemorrhage. They are reviewed by highly skilled professionals to find the existence, location and type of hemorrhage. This process is complex, labor-intensive and requires lot of time. The massive progress in machine learning techniques and availability of high computational power has made it possible to detect such hemorrhages automatically. The paper provides survey of recent deep learning approaches for automatic detection of such acute intracranial hemorrhage and its subtypes. Further the experimental results using windowing technique inspired by practical radiologist’s approach and relevant research papers is provided to verify its efficacy as a pre-processing step before feeding DICOM images to the network. Transfer learning approach is used to detect hemorrhage types. The open source Kaggle platform is utilized for computational resources and for carrying out the experimental study. Some key evaluation metrics and loss functions addressing the data imbalance underlying with the problem statement are also presented. The paper concludes with addressing key insights into open issues in the proposed domain.
Abstract 1402: HNRNPA2B1 increases the serine synthesis pathway in endocrine-resistant breast cancer cells

Despite the limited success of new combination therapies with fulvestrant improving survival of breast cancer patients with metastatic disease after initial response to endocrine therapies based on primary estrogen receptor alpha (ER+) tumors, mechanisms for acquired endocrine resistance remain to be fully elucidated. The RNA binding protein HNRNPA2B1, a reader of epitranscriptomic N(6)-methyladenosine (m6A) in transcribed RNA, is upregulated in endocrine-resistant, ER+ LCC9 and LY2 cells compared to parental MCF-7 endocrine-sensitive luminal A breast cancer cells. HNRNPA2B1 regulates pri- to pre- miRNA processing as well as splicing and transcript stability, depending on interacting proteins and cellular context. The miRNA-seq transcriptome of MCF-7 cells transiently overexpressing HNRNPA2B1 identified gene ontology (GO) pathways including cellular response to steroid hormone signaling and serine family amino acid metabolic processes, i.e., the serine synthesis pathway (SSP). Stable, modest (4.5-fold) overexpression of HNRNPA2B1 in MCF-7 cells (MCF-7-A2B1 cells) phenocopies the endocrine-resistance of LCC9 and LY2 cells including ablation of growth inhibition by 4-hydroxytamoxifen (4-OHT) and fulvestrant. This was not the result of decreased ER alpha; rather, ER alpha, and androgen receptor (AR), were increased. Conversely, transient knockdown of HNRNPA2B1 in LCC9 and LY2 cells sensitized the cells to growth inhibition by 4-OHT and fulvestrant. MCF-7-A2B1 cells, like LCC9 and LY2 cells, have higher expression of phosphoglycerate dehydrogenase (PHGDH) and phosphoserine aminotransferase (PSAT1) transcripts and proteins compared to MCF-7 cells. We identified two miRNAs, miR-424-5p and miR-145-5p downregulated in MCF-7-A2B1 cells that directly target the PSAT1 39UTR in dual luciferase assays. Lower miR-424-5p and miR-145-5p in endocrine-resistant LCC9 and LY2 correlate with increased PSAT1 and higher PSAT1 is associated with reduced overall and metastasis-free survival in breast cancer patients. The correlation of HNRNPA2B1 and PSAT1 expression was examined by IHC in a breast tumor/tissue microarray. Overall, our data suggest a role for increased HNRNPA2B1 in endocrine-resistance and upregulation of the SSP to promote tumor progression in ER+ breast cancer. Citation Format: Carolyn M. Klinge, Belinda J. Petri, Kellianne M. Piell, Brian C. Clem. HNRNPA2B1 increases the serine synthesis pathway in endocrine-resistant breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1402.
Surgical Scheduling Impacts Hospital Length of Stay and Associated Healthcare Costs for Patients Undergoing Total Hip and Knee Arthroplasty

Background:Surgical scheduling, specifically the day of the week on which surgery is performed, has been associated with various postoperative outcomes in patients undergoing lower extremity joint ...
Extreme Heat Related Mortality: Spatial Patterns and Determinants in the United States, 1979–2011

Extreme heat has been responsible for more deaths in the United States than any other weather-related phenomenon over the past decade. The frequency and intensity of extreme heat events are projected to increase over the course of this century. In this work, we examine historical patterns of extreme heat exposure and mortality in the continental United States. We examine spatial variation in the mortality response to exposure, consider the contribution of key demographic and socio-economic factors in driving heat-related mortality, and test three different extreme heat thresholds using a national-level spatial autoregressive model and a geographically weighted regression approach. We find that the mortality response to exposure is higher in areas that do not routinely experience heat extremes, and that exposure itself is a stronger driver of heat-related mortality across the larger urban areas of the Midwest and Northeast. The importance of demographic/socio-economic factors varies substantially over space, and results are robust across alternative measures of heat extremes, suggesting that no single definition is necessarily superior. The baseline relationships established here are potentially useful for future predictions of exposure and heat-related mortality under alternative population and climate change scenarios, and may aid policy makers and planners in implementing effective adaptation and mitigation strategies.
Liver Transplantation for NASH-Related Cirrhosis

Nonalcoholic steatohepatitis (NASH) is on a trajectory to become the leading indication for liver transplantation. It is an important risk factor for hepatocellular carcinoma and chronic kidney disease and, as such, is poised to have a major impact on the liver transplant community in the coming decades. While the optimal approach to the patient with NASH-related cirrhosis is evolving, careful attention to the cardiovascular, metabolic, renal, and obesity risk factors represents the mainstay of treatment. Management of these factors also offer the greatest opportunity for improvement of long-term outcomes in these patients.
The Outer Mitochondrial Membrane, a Smooth ‘Coat’ with Many Holes and Many Roles: Preparation, Protein Components, Interactions with Other Membranes, Involvement in Health, Disease, and as a Drug Target

Mitochondria were first isolated near the middle (1948) of the past century, visualized shortly thereafter by electron microscopy, and each mitochondrion was shown to consist of four major compartments: (1) an outer membrane (the subject of this article), (2) an inner membrane, (3) an intermembrane space located between the two membranes, and (4) a matrix, soluble space surrounded by the inner membrane. As ATP synthesis (oxidative phosphorylation) was shown to be associated with the inner membrane, the outer membrane drew little attention for many years and was not subjected to serious analysis until the late 1960s. Meticulous and very difficult work resulted in the separation of mitochondria into four distinct fractions, each representing one of its four major compartments, and this article focuses on the outer mitochondrial membrane summarizing its preparation, characterization, and roles in cellular life and death and its impact on health and disease.
SU-E-T-325: Dosimetric Impact Due to FlexiShield in Electronic Brachytherapy (eBx) of Breast IORT: A Phantom Study

Purpose: To evaluate dosimetric change of eBx plan due to Flexishield. Methods: To simulate a clinically difficult case (skin spacing < 1 cm and touching chest wall), prostheses breast tissue phantom overlaid Xoft spherical balloon applicator. To minimize significant metal streak artifact, megavoltage CT (MVCT) scan was acquired using helical TomoTherapy HiART. Two sets of MVCT images were taken with/without FlexiShield for 15 cases: 4 for small (3–4 cm), 4 for medium (4–5 cm) and 7 for large (5–6 cm) balloon. Total 30 MVCT scans were obtained with 50 % contrast to improve image contrast of balloon relative to breast tissue phantom. Balloon deformation was measured in anterior-posterior (AP) and lateral (LAT) dimensions in the middle of balloon. Skin spacing was also evaluated. Treatment plan was made based on each MVCT scan and two balloon surface doses (AP and LAT directions) and skin dose were compared between plans with/without FlexiShield. Results: The balloon was deformed due to pressure from both FlexiShield (skin side) and FlexiShield mini (chest wall side). Mean ± standard deviation (maximum) value was 1.5 ± 1.0 mm (3.3 mm) for AP compression and 0.4 ± 0.3 mm (1.1 mm) for LAT expansion. Balloon surface dose was increased by 1.8 ± 1.2 Gy (4.9 Gy) at AP point and decreased by 0.4 ± 0.4 Gy (1.3 Gy) at LAT point. Skin spacing was constantly reduced by 1.1 ± 0.8 mm (3 mm). Skin surface dose was increased by 1.5 ± 0.8 Gy (3.3 Gy) and its relative increase was 17.9 ± 9.3% (39.6%). Conclusion: FlexiShield deforms the balloon and reduces skin spacing, thereby resulting in higher dose in AP direction, lower dose in LAT direction, and elevated skin dose compared to the plan without FlexiShield. In the clinic, this balloon deformation and corresponding dose variation should be considered.
The Haloing Effect of the Third Integral

Whether Contopoulos's galactic system is separable (unlikely) or not (likely), the fact is that there exists a vicinity of the equilibrium in which numerical integration of high accuracy cannot separate the system from its image through Birkhoff's normalization of high order. To all practical purposes, stellar dynamics is then justified in pretending that the model is, in that region, structured by a so-called third integral.
Boechera, a model system for ecological genomics

The selection and development of a study system for evolutionary and ecological functional genomics (EEFG) depend on a variety of factors. Here, we present the genus Boechera as an exemplary system with which to address ecological and evolutionary questions. Our focus on Boechera is based on several characteristics as follows: (i) native populations in undisturbed habitats where current environments reflect historical conditions over several thousand years; (ii) functional genomics benefitting from its close relationship to Arabidopsis thaliana; (iii) inbreeding tolerance enabling development of recombinant inbred lines, near-isogenic lines and positional cloning; (iv) interspecific crosses permitting mapping for genetic analysis of speciation; (v) apomixis (asexual reproduction by seeds) in a genetically tractable diploid; and (vi) broad geographic distribution in North America, permitting ecological genetics for a large research community. These characteristics, along with the current sequencing of three Boechera species by the Joint Genome Institute, position Boechera as a rapidly advancing system for EEFG studies.
The Nordic borders are not alike

AimTo pinpoint the most important and interesting border trade areas for alcoholic beverages in the Nordic countries and to investigate patterns of routes and directions of border trade with alcoho...
Design and implementation of an algorithmic S/sup 2/I switched-current multiplier

The analysis, design and implementation of a S/sup 2/I switched-current multiplier is presented. A thorough circuit analysis of the multiplier and its nonidealities is presented with a design procedure. It has been implemented using a 2 /spl mu/m n-well CMOS technology. The following are brief highlights of the measurement results: (i) 0.425 millions of multiplication per second, (ii) 1.7% total harmonic distortion for a sinusoidal of 35 /spl mu/A (50 Hz), (iii) 206 kHz of bandwidth, (iv) 50 dB of SNR and (v) 0.3 mW zero input power consumption for a /spl plusmn/3 V power supply. A complete set of detailed experimental results is provided in the paper.
Maternal hypoxia and caffeine exposure depress fetal cardiovascular function during primary organogenesis

Aims: Hypoxia is known to influence cardiovascular (CV) function, in part, through adenosine receptor activation. We have shown in a mouse model that during primary cardiac morphogenesis, acute maternal hypoxia negatively affects fetal heart rate, and recurrent maternal caffeine exposure reduces fetal cardiac output (CO) and downregulates fetal adenosine A2A receptor gene expression. In the present study, we investigated whether maternal caffeine dosing exacerbates the fetal CV response to acute maternal hypoxia during the primary morphogenesis period. Material and Methods: Gestational-day-11.5 pregnant mice were exposed to hypoxia (45 s duration followed by 10 min of recovery and repeated 3 times) while simultaneously monitoring maternal and fetal CO using high-resolution echocardiography. Results: Following maternal hypoxia exposure, maternal CO transiently decreased and then returned to pre-hypoxia baseline values. In contrast to a uniform maternal cardiac response to each exposure to hypoxia, the fetal CO recovery time to the baseline decreased, and CO rebounded above baseline following the second and third episodes of maternal hypoxia. Maternal caffeine treatment inhibited the fetal CO recovery to maternal hypoxia by lengthening the time to CO recovery and eliminating the CO rebound post-recovery. Selective treatment with an adenosine A2A receptor antagonist, but not an adenosine A1 receptor antagonist, reproduced the altered fetal CO response to maternal hypoxia created by caffeine exposure. Conclusions: Results suggest an additive negative effect of maternal caffeine on the fetal CV response to acute maternal hypoxia, potentially mediated via adenosine A2A receptor inhibition during primary cardiovascular morphogenesis.
From Bedside to Graveside: Increased Stress among Healthcare Chaplains:

The authors conducted a survey of Baylor Health Care System chaplains in an attempt to understand the stress they experience when leading funeral services of staff, staff family members, and patients. The intensity of stress experienced by these chaplains appears to be related to the cause of death, the deceased's age, and the relationship the deceased had with the chaplain. Further research is needed to corroborate these findings as well as to investigate how chaplains manage their own grief when they are involved in the grief experiences of patients and families.
Structural Characterization of Intramolecular Hg2+ Transfer between Flexibly Linked Domains of Mercuric Ion Reductase

The enzyme mercuric ion reductase MerA is the central component of bacterial mercury resistance encoded by the mer operon. Many MerA proteins possess metallochaperone-like N-terminal domains (NmerA) that can transfer Hg(2+) to the catalytic core domain (Core) for reduction to Hg(0). These domains are tethered to the homodimeric Core by ~30-residue linkers that are susceptible to proteolysis, the latter of which has prevented characterization of the interactions of NmerA and the Core in the full-length protein. Here, we report purification of homogeneous full-length MerA from the Tn21 mer operon using a fusion protein construct and combine small-angle X-ray scattering and small-angle neutron scattering with molecular dynamics simulation to characterize the structures of full-length wild-type and mutant MerA proteins that mimic the system before and during handoff of Hg(2+) from NmerA to the Core. The radii of gyration, distance distribution functions, and Kratky plots derived from the small-angle X-ray scattering data are consistent with full-length MerA adopting elongated conformations as a result of flexibility in the linkers to the NmerA domains. The scattering profiles are best reproduced using an ensemble of linker conformations. This flexible attachment of NmerA may facilitate fast and efficient removal of Hg(2+) from diverse protein substrates. Using a specific mutant of MerA allowed the formation of a metal-mediated interaction between NmerA and the Core and the determination of the position and relative orientation of NmerA to the Core during Hg(2+) handoff.
A Hidden Markov Model Based Tool for Geophysical Data Exploration

Unsupervised learning techniques provide a way of investigating scientific data based on automated generation of statistical models. Because these techniques are not dependent on a priori information, they provide an unbiased method for separating data into distinct types. Thus they can be used as an objective method by which to identify data as belonging to previously known classes or to find previously unknown or rare classes and subclasses of data. Hidden Markov model based unsupervised learning methods are particularly applicable to geophysical systems because time relationships between classes, or states of the system, are included in the model. We have applied a modified version of hidden Markov models which employ a deterministic annealing technique to scientific analysis of seismicity and GPS data from the southern California region. Preliminary results indicate that the technique can isolate distinct classes of earthquakes from seismicity data.
A framework approach to teaching data structures

This paper advocates the incorporation of object oriented framework libraries such as the Standard Template Library (STL) into the first data structures course at the university level. This represents a shift from learning the details of each data structure to an increased emphasis on the use, integration, and extension of these existing frameworks, as well as on the learning of higher-order design and engineering skills.
The Solar Magnetograph of the High Altitude Observatory

Solar magnetograph to measure magnetic field intensities in solar prominences, utilizing H- alpha emission line
Linear dependence of a function set of m variables with vanishing generalized Wronskians

Abstract Necessary and sufficient conditions are established for a set of n functions φi : Em → E1, which together with their partial derivatives of order at least n − 1 are continuous, to be linearly dependent. One of these conditions is that all generalized Wronskians vanish identically.
Problems in determining nuclear bound state wave functions

The interior part of a bound state is difficult to determine empirically. We use momentum space singularity structure to show that final state interactions, rescattering, exchange currents, etc., always act so as to obscure the bound state interior. The asymptotic part of the bound state can be measured for sufficiently ''light'' components. We apply these results to explain why the deuteron D-state probability cannot be fixed and why it is difficult to give meaning to the idea of ..pi..-N resonances in the nucleus. We treat bound state breakup, elastic scattering, and form factors.
Habituation of fear: effects of intensity and stimulus order.

This study investigated snake-fearful subjects' skin conductance, heart rate, and fear ratings to repeated presentations of seascape and snake films (10–13 sec duration). The films sampled three levels of fear intensity and were displayed in ascending, descending, or nonsystematic orders; additional Ss viewed only high-fear material. A linear relationship with fear intensity emerged for fear ratings, but not for physiological measures. Differences found between orders in patterns of habituation were concordant for cardiac rate and fear ratings; relative to the other orders, the ascending sequence habituated less and displayed sensitization to material of higher fear levels. In all orders, there was marked habituation of physiological responses, especially in the first session. The possible role of adaptation level and implications of the data for desensitization and flooding were noted.
Non-Debye dielectric response and distribution of activation energies

Abstract The non-Debye dielectric response is characterized by a broad loss peak and a constant-phase-angle behavior at frequencies above the loss peak. In this work, the main features of the distribution of activation energies, G ( E ), for some empirical functions frequently used to describe this behavior, such as the Havriliak-Negami and the Williams-Watts functions, are analyzed and compared with the double-exponential G ( E ) obtained from the ion-hopping model. A possible basis for the ion-hopping model and its relation with the Debye model are discussed.
Modification of photochemical reactivity by zeolites. A comparison between zeolite-solvent slurry and dry solid photolyses

The use of a zeolite-solvent slurry as a convenient medium to carry out photoreactions is illustrated with four examples, namely Norrish type I reaction of dibenzyl ketones, Norrish type I and type II reactions of α-alkylbenzyl benzyl ketones, Norrish type II reaction of aryl alkyl ketones, and photodimerization of acenaphthylene
Hemolysate Induces Tyrosine Phosphorylation and Collagen-Lattice Compaction in Cultured Fibroblasts

Hemolysate, a proposed causative agent for cerebral vasospasm after subarachnoid hemorrhage, produces contraction of cerebral arteries by activation of tyrosine kinases. In addition, hemolysate increases fibroblast-collagen compaction that could play a role in cerebral vasospasm. We studied the effect of hemolysate on tyrosine phosphorylation and fibroblast-collagen compaction in cultured canine basilar and human dermal fibroblasts using tyrosine kinase inhibitors and tyrosine antibodies. Hemolysate enhanced tyrosine phosphorylation of two proteins, 64 and 120 kDa, in cultured canine basilar artery and human dermal fibroblast cells. The effect of hemolysate was time-dependent and concentration-dependent. Oxyhemoglobin and ATP, the two major components of hemolysate, produced similar tyrosine phosphorylation, however, with a different time course. Tyrosine kinase inhibitors genistein and tyrphostin A51 abolished the effect of hemolysate in both cerebral and dermal fibroblasts. Hemolysate increased fibroblast-populated collagen-lattice compaction and tyrosine kinase inhibitors genistein and tyrphostin A51 attenuated the effect of hemolysate. We conclude that hemolysate activates tyrosine kinase that leads to the increase of fibroblast compaction. This effect of hemolysate may contribute to cerebral vasospasm.
Metastable and collision-induced fragmentation of selected C3H6S+· isomers; evidence for extensive isomerization

The metastable ion (MI) and collision-induced dissociation (CID) mass spectra of five C3H6S+· isomers were examined. The MI mass spectra were virtually identical, which suggests that C3H6S+· ions having a substantial amount of internal energy can freely interconvert and isomerize into a common structure prior to fragmentation. However, the CID mass spectra are distinctly different and the differences can be related to the structure of the C3H6S+· isomers. It was even possible to distinguish the distonic ion H2CCH2SCH2+· from its conventional counterpart . The smaller amount of internal energy of the ions probed in CID experiments obviously limits isomerization.
Reminiscence: Evidence for reorganization in final free recall

Sixty subjects learned four different 16-word lists in four different conditions. Within each list, every word was repeated. The four conditions were defined by a 2 (whole vs. blocked presentation) by 2 (same order vs. random order repetition) factorial design. An unexpected final free recall followed the immediate free recall of the fourth list. It was found that significantly more reminiscence occurred in the whole-random condition, suggesting that initially imposed organization hindered the subsequent reorganization.
Statistical Determination of Natural Gas Superheat Requirements

The ASME Fuel Specification B133.7M [1] states that a typical margin of 25 to 30° C (45 to 54° F) of superheat is used for natural gas fuel but offers no basis for the estimate. The purpose of this paper is to propose a method for the safe determination of superheat that is less conservative, yet will meet the six sigma requirement of less than 4 defects (condensate formation) in one million opportunities. A drop in the total temperature of natural gas will be experienced as the gas expands in pressure reducing stations and across control valves. If the temperature falls below the hydrocarbon or moisture dew point, condensation will take place and liquids will collect or will be entrained with the gas. The temperature drop is inversely proportional to the pressure drop and is often termed ‘Joule-Thomson cooling’ or ‘J-T cooling’. The rate of cooling is described by the Joule-Thomson coefficient that can be determined by experiment or calculated from the gas composition. Superheating the gas prior to expansion can prevent condensation. The degree of superheat required for hydrocarbons, however, is often greater than the expected temperature loss across the valve as the hydrocarbon dew point may increase as the pressure falls. This paper describes a method for determining the quantity of superheat required for a specific gas composition and develops a general equation in terms of gas supply pressure that will satisfy the needs for the majority of natural gases. The general equation is based on the statistical analysis of superheat requirements for over 230 natural and liquefied natural gas compositions. A similar equation is also presented that describes the superheat requirements to avoid moisture condensation. The two equations can be used to specify the heating requirements upstream of pressure reducing stations or control valves.© 2002 ASME
Tactile Vision Substitution: Past and Future

Tactile sensory substitution for blind persons has been studied primarily in a laboratory setting. Although the studies demonstrated the feasibility of the approach, to date no practical systems are in use. In this paper, previous tactile vision substitution studies are described, and the reasons why practical systems have not yet been developed are discussed. The theoretical basis for sensory substitution is examined primarily in regard to the capacity of the somatosensory system to mediate high resolution “visual” information. Future developments that may lead to practical systems for blind persons are considered.
Teaching Case: Improvement of Chronic Chylous Pleural Effusion Using a Restricted Fat Diet and Medium Chain Triglycerides in a Patient with Congenital Lymphangiectasia

Congenital lymphangiectasia is a rare disease of the lymphatic system often causing respiratory symptoms from chylous pleural effusions. Treatment options for these effusions include drainage by multiple thoracenteses or chest thoracostomy tube placement. Previous studies have reported the efficacy of surgical intervention with adjunctive nutrition therapy using total parenteral nutrition (TPN) in decreasing chylous effusions. Few reports, however, describe the use of very low-fat diets with medium chain triglycerides (MCT) as a therapeutic option. Objective: In order to help manage recurrent pleural effusions in a 28-year-old woman with a history of congenital lymphangiectasia, an oral diet restricted in fat using MCT was administered. Methods: The patient was treated with a very low-fat diet, with fat consumption approximately 5% of total caloric intake using food sources and MCT oil. Her diet was supplemented with a multivitamin and linoleic essential fatty acid. Results: After implementation of this d...
The incorporation of triethylcholine into isolated guinea pig cerebral cortex synaptosomal and synaptic vesicle fractions

The incorporation of triethylcholine (TEC) into synaptosomal and synaptic vesicle fractions prepared from guinea pig cerebral cortices was investigated. TEC was tritium labelled by a catalytic exchange process and purified by thin layer chromatography. 3H-TEC was incorporated into isolated synaptosomal fractions in both tris medium and a complete medium containing an external energy source. In this medium about 50% of the 3H-TEC incorporated was taken up into a chloroform-soluble fraction; almost no uptake into chloroform was demonstrated in the complete medium. After incubation of 3H-TEC with isolated synaptosomal fractions the 3H-TEC was shown to be localized in the subsynaptosomal synaptic vesicle fraction. The uptake process for 3H-TEC is inhibited by high concentrations of hemicholinium and choline. The temperature and time studies suggest that in synaptosomes an uptake process for TEC exists similar to that which has been observed for choline.
Effect of Trephine Tilt on Corneal Button Dimensions

Wound disparity, mismatch between the size and shape of the donor corneal button and its wound, probably determines the direction and amount of postkeratoplasty astigmatism. Tilting a hand-held trephine is thought to contribute to an oval wound and to wound disparity. We examined the contribution of trephine tilt to wound size and shape. Eyebank eyes were hand trephined at 0, 5, 10, 15, 20, and 25 degrees of tilt. The button endothelial edges were analyzed by the photogrammetric index method. All index values were significantly different from those for a theoretically circular or symmetric button. Although the most oval buttons were at 20 and 25 degrees, buttons were similarly oval and asymmetric for trephine tilt from 0 to 15 degrees. Neither ovality nor asymmetry correlated with angle of tilt. Even when no attempt is made to tilt a hand-held trephine, oval and irregularly shaped wounds may result.
A review of the derivative thermogravimetric technique (burning profile) for fuel combustion studies

Abstract Burning profiles obtained by derivative thermogravimetric analysis are useful for obtaining relative combustion characteristics of fuels and for predicting combustion performance in boilers. However, the interpretation of these profiles is not always straightforward, particularly with respect to the combustion peaks. In this paper, the use of burning profiles for coal reactivity studies is reviewed. Factors which affect the appearance of the combustion peaks in the burning profiles and complicate data interpretation are summarized. Special emphasis is given to catalytic effects, because this factor is often not adequately considered when interpreting the data.
Required grading length to eliminate the heterojunction spike in npn In0.52Al0.48As/In0.53Ga0.47As/InP bipolar transistors

Energy-band diagrams have been studied for n-In0.52Al0.48As/p-In0.53Ga0.47As heterojunctions employing different compositional gradings for heterojunction bipolar transistor applications, and the minimum grading widths were calculated for eliminating the conduction-band spike barrier.
Nucleic Acid Synthesis in Seedlings

As little as one part in 107 by weight of contaminating bacteria can alter the labelling of seedling nucleic acids with phosphorus-32. The bacterial nucleic acids are labelled in preference to those of the plant cells. With seedlings free of bacteria the labelling occurs at a slower rate. Systems involving the labelling of nucleic acids should be tested for bacterial contamination.
Non-steady state intermediates: a re-examination of the kinetics of hydrolysis of N-methylisobutylidene and N-isopropylethylidene under acidic conditions

Direct measurement by stopped flow and UV–vis spectroscopy of the decay of two protonated imines, N-methylisobutylidene and N-isopropylethylidene, below a pH 3 resulted in a biphasic kinetic profile involving a rapid decay of the iminium ion to a carbinolamine intermediate. Previously published hydrolysis studies on N-methylisobutylidene did not report observation of non-first order kinetics. Spectroscopic evidence of the carbinolamine intermediate of N-methylisobutylidene was observed by 1H NMR. The rate constants for the pH independent step, k1, were similar for both compounds, 0.94 s−1 for N-methylisobutylidene versus 0.87 s−1 for N-isopropylethylidene. Following k1, the rate constants, k−1 and k±Ka(OH) differed by a factor of approximately 3 with the carbinolamine intermediate of N-isopropylethylidene being more stable over the carbinolamine of N-methylisobutylidene. An in-depth examination of the rate constants is presented.
Developmental Differences in Children's Search of Predecisional Information.

Abstract Developmental differences in children's decision-making were examined using an information-board procedure. In Experiment 1, fifth and eighth graders remembered more initial, relevant information from decision situations than second graders. Older children were also more likely than younger children to use this information to guide their searches of information from information boards. In Experiment 2, visual cues were provided, eliminating the need to store initial information. This manipulation increased fifth graders' search of relevant information more so than that of second graders. General characteristics about children's decision making were also examined, such as the amount and proportion of predecisional information searched, and the manner in which information was searched.
Before it's too late : the child guidance movement in the United States, 1922-1945

During the Progressive Era, the child guidance movement began as part of the Commonwealth Fund's "Program for the Prevention of Juvenile Delinquency." During its years as a Commonwealth Fund project (1922-1945) the movement grew from a community effort for the prevention of mental illness to a field of specialty practice in psychiatry, psychology, and social work. Employing the newly accessible archives of the Commonwealth Fund, Margo Horn presents the complex history of the child guidance movement in relation to the mental health professions, philanthropic foundations, and the American family.Originally focused on the identification of the "problem child," the establishment of child guidance clinics, and programs to promote community mental health, the movement gradually shifted its goals toward the training of child guidance professionals and the monitoring of growth and treatment by the clinics. The idealistic concern over community mental health became a concern over professional standards and status with the fields of psychiatry, psychology, and social work vying for prominence. Within the context of this transition, Horn examines the ways in which the family and children increasingly came under the scrutiny of "experts." Margo Horn directs the Innovative Academic Courses Program and teaches History at Stanford University.
Tumor necrosis factor-α mRNA and protein in endometrial tumors: Analysis by in situ hybridization and immunocytochemistry

Abstract Abnormal expression of polypeptide growth factors and their receptors is closely associated with tumorigenic transformation. In this study tumor necrosis factor-α (TNF-α) mRNA and protein were analyzed in polyps and proliferative lesions of endometrium as well as in low and high grade endometrial tumors by using in situ hybridization and immunocytochemistry. All samples contained products of the TNF-α gene. Histochemical scores (HS), which reflect the proportion of cells positive for TNF-α message or protein and the intensities of the signals, were higher for epithelial than for stromal cells. Benign lesions (endometrial polyps) contained little TNF-α mRNA or protein, whereas specific message was abundant in proliferative lesions (hyperplasia, adenofibroma). Although neoplastic cells in both low and high grade endometrial tumors contained TNF-α mRNA, two major differences were observed: HS for TNF-α mRNA were significantly less in low grade than in high grade neoplasms, and TNF-α message was restricted to the nucleus in low grade adenocarcinoma cells but was abundant in the cytoplasm of high grade tumor cells. In contrast to cells in benign and proliferative lesions, TNF-α protein scores in endometrial tumor cells were inversely rather than positively correlated with TNF-α mRNA scores. Collectively, the findings in this study are consistent with the postulate that TNF-α is useful to endometrial tumor cells and suggest that production may increase as cells diverge from normal.
Quantitation of RNA using the polymerase chain reaction

Sequential use of reverse transcriptase and the polymerase chain reaction (RT-PCR) permits rapid and sensitive detection of specific RNAs. However, the greatest advantage of RT-PCR, its remarkable sensitivity, has also limited its usefulness in quantitative applications, since the effects of minor variations in reaction conditions from sample to sample are greatly magnified during the amplification process. Several recently developed techniques circumvent this problem, allowing accurate quantitation of RNA using RT-PCR.
Filamentous phages linked to virulence of Vibrio cholerae.

Abstract The pathogenicity of Vibrio cholerae depends upon its production of two key virulence factors: the toxin co-regulated pilus (TCP), a colonization factor, and cholera toxin, an exotoxin. Genes encoding both virulence factors were introduced into V. cholerae by horizontal gene transfer. The toxin genes are contained within the genome of CTXφ, an integrated filamentous phage identified in 1996. In the past few years, it has been shown that CTXφ relies on novel processes for phage DNA integration, replication and secretion. In addition, expression of CTXφ genes — including the toxin genes — and transmission of CTXφ were recently found to be promoted by the antirepressor RstC, which is encoded within RS1, a newly described satellite phage of CTXφ. The genetic island that encodes TCP has also been described as a filamentous phage; however, these sequences are unlike the genome of any previously characterized filamentous phage.
Visualization of three-dimensional flow in a four-roll mill

Flow visualization has been used to study the motion of a Newtonian fluid in a four-roll mill. Observations of the effect of increasing Reynolds number on the evolution of steady three-dimensional flow between the rollers are reported. The flow visualization experiments have been conducted for two values of the aspect ratio (defined as the ratio of roller length to gap width between rollers). The rollers have been constrained to rotate in a manner which generates an approximately two-dimensional pure extensional flow near the center of the apparatus at low speeds. Steady, symmetrically positioned vortices grow near the top and bottom walls of the container as the Reynolds number is increased up to a critcal value. An increase in Reynolds number beyond this critical value results in a loss of symmetry in the flow pattern. The nature of this transition is strongly dependent upon the aspect ratio.