cssi/SciSciGPT-SciSciNet huggingface dataset:
Responses of Texas estuaries to freshwater inflows.

Six of the seven major estuarine systems on the Texas coast are compared using geomorphic, hydrologic, hydrographic, nutrient loading, and commercial fishery harvest indices as common bases. While the geomorphic characteristics of these systems are relatively similar, major differences are found in annual freshwater inflows, precipitation and evaporation patterns, and hydraulic residence times, as well as tidal exchange influenced residence times. Biotic composition is relatively similar except where salinity tolerance limitations reduce populations of finfish and shellfish. Nutrient budgets show that nutrient inputs are dominated by freshwater inflows, with exchange from saltwater and delta marshes and precipitation providing a small fraction of the inflow. Finfish and shellfish harvests are shown to be functions of average salinity of the estuaries as well as of areal loading rates of nutrients.
Sexual Desire, Mood, Attachment Style, Impulsivity, and Self-Esteem as Predictive Factors for Addictive Cybersex.

Background: An increasing number of studies are concerned with various aspects of cybersex addiction, the difficulty some persons have in limiting cybersex use despite a negative impact on everyday life. Objective: The aim of this study was to assess potential links between the outcome variable cybersex addiction, assessed with the Compulsive Internet Use Scale (CIUS) adapted for cybersex use, and several psychological and psychopathological factors, including sexual desire, mood, attachment style, impulsivity, and self-esteem, by taking into account the age, sex, and sexual orientation of cybersex users. Methods: A Web-based survey was conducted in which participants were assessed for sociodemographic variables and with the following instruments: CIUS adapted for cybersex use, Sexual Desire Inventory, and Short Depression-Happiness Scale. Moreover, attachment style was assessed with the Experiences in Close Relationships-Revised questionnaire (Anxiety and Avoidance subscales). Impulsivity was measured by using the Urgency, Premeditation (lack of), Perseverance (lack of), Sensation Seeking, Positive Urgency Impulsive Behavior Scale. Global self-esteem was assessed with the 1-item Self-Esteem Scale. Results: A sample of 145 subjects completed the study. Addictive cybersex use was associated with higher levels of sexual desire, depressive mood, avoidant attachment style, and male gender but not with impulsivity. Conclusions: Addictive cybersex use is a function of sexual desire, depressive mood, and avoidant attachment.
Structural Analysis of Proteins of the Nervous System

Proteins and peptides are essential to normal development, growth, and function of the nervous system1. The structural analysis of these proteins and peptides is complicated by the difficulty in obtaining sufficient material for complete, chemical characterization. It is difficult to obtain a homogeneous population of cells to serve as the starting material for protein isolation because the tissues of the nervous system, including brain, spinal cord, peripheral nerves, and sensory systems, are composed of multiple cell types2. Primary cultures of specific populations of cells3, 4 have been useful as models of neural development and function but are limited in their general application. Systems of cultured cells 5, 6, such as embryonic neurons, glia, neuroblastomas, or gliomas, that proliferate in culture also have limited roles as models of normal nervous system function. Therefore, upon purification land characterization of a protein of the nervous system, it is imperative to return to the whole organism to demonstrate the physiological function, anatomical distribution, and pharmacological regulation of the protein. In this way, the structural analysis of proteins of the nervous system is one part of a multidisclplinary approach to neuroscience.
Activity and anion inhibition studies of the α-carbonic anhydrase from Thiomicrospira crunogena XCL-2 Gammaproteobacterium.

Abstract Thiomicrospira crunogena XCL-2 expresses an α-carbonic anhydrase (TcruCA). Sequence alignments reveal that TcruCA displays a high sequence identity (>30%) relative to other α-CAs. This includes three conserved histidines that coordinate the active site zinc, a histidine proton shuttling residue, and opposing hydrophilic and hydrophobic sides that line the active site. The catalytic efficiency of TcruCA is considered moderate relative to other α-CAs ( k cat / K M = 1.1 × 10 7 M −1 s −1 ), being a factor of ten less efficient than the most active α-CAs. TcruCA is also inhibited by anions with Cl − , Br − , and I − , all showing K i values in the millimolar range (53–361 mM). Hydrogen sulfide (HS − ) revealed the highest affinity for TcruCA with a K i of 1.1 μM. It is predicted that inhibition of TcruCA by HS − (an anion commonly found in the environment where Thiomicrospira crunogena is located) is a way for Thiomicrospira crunogena to regulate its carbon-concentrating mechanism (CCM) and thus the organism’s metabolic functions. Results from this study provide preliminary insights into the role of TcruCA in the general metabolism of Thiomicrospira crunogena .
The Wonders of Night Hiking

(1974). The Wonders of Night Hiking. Journal of Health, Physical Education, Recreation: Vol. 45, No. 8, pp. 8-8.
Translational Ecology and Environmental Law

Translational ecology is a comparatively new approach to the pursuit of ecology and other environmental sciences, the implications of which for environmental law have not previously been explored significantly. Emulating the concepts of translational medicine, proponents of transactional ecology seek to increase the relevance of their research to important environmental problems by improving how effectively they communicate research results to end users of that science, collaborating with those end users to identify research that is “actionable” rather than purely “curiosity-driven” or theoretical, recognizing that values as well as science have a legitimate role in environmental decisions, and engaging in ongoing dialogues about the relationship between science and other issues and values to build trust across disciplines. Several major federal environmental statutes provide examples of ways in which the practice of translational ecology could contribute to better implementation of environmental laws. More broadly, translational ecology has the potential to transform the relationship between science and law in setting and implementing environmental policy.
Relationships between breast feeding and breast cancer subtypes: lessons learned from studies in humans and in mice

There are differential risk relationships between parity and breast cancer according to estrogen receptor (ER) status, with an increased risk of ER- disease reduced by breastfeeding. This may be particularly relevant for understanding the higher incidence of ER- tumors in Black women, who are more likely to be parous and less likely to breastfeed than other U.S. groups. Potential mechanisms for these relationships may include effects of disordered breast involution on inflammatory milieu in the breast as well as epigenetic reprogramming in the mammary gland, which can affect cell fate decisions in progenitor cell pools. In normal breast tissue, parity has been associated with hypermethylation of FOXA1, a pioneer transcription factor that promotes the luminal phenotype in luminal progenitors, while repressing the basal phenotype. In breast tumors, relationships between FOXA1 methylation and parity were strongest among women who did not breastfeed. Here, we summarize the epidemiologic literature regarding parity, breastfeeding, and breast cancer subtypes, and review potential mechanisms whereby these factors may influence breast carcinogenesis, with a focus on effects on progenitor cell pools in the mammary gland.
Calculating Glycoprotein Similarities From Mass Spectrometric Data

Abstract Complex protein glycosylation occurs through biosynthetic steps in the secretory pathway that create macro- and microheterogeneity of structure and function. Required for all life forms, glycosylation diversifies and adapts protein interactions with binding partners that underpin interactions at cell surfaces and pericellular and extracellular environments. Because these biological effects arise from heterogeneity of structure and function, it is necessary to measure their changes as part of the quest to understand nature. Quite often, however, the assumption behind proteomics that posttranslational modifications are discrete additions that can be modeled using the genome as a template does not apply to protein glycosylation. Rather, it is necessary to quantify the glycosylation distribution at each glycosite and to aggregate this information into a population of mature glycoproteins that exist in a given biological system. To date, mass spectrometric methods for assigning singly glycosylated peptides are well-established. But it is necessary to quantify glycosylation heterogeneity accurately in order to gauge the alterations that occur during biological processes. The task is to quantify the glycosylated peptide forms as accurately as possible and then apply appropriate bioinformatics algorithms to the calculation of micro- and macro-similarities. In this review, we summarize current approaches for protein quantification as they apply to this glycoprotein similarity problem.
Implementing the Restoring Force Surface Method to Fit Experimentally Measured Modal Coupling Effects

In complex structures, particularly those with jointed interfaces, the dynamic response of individual modes can behave nonlinearly. To simplify analyzing and modeling this response, it is typically assumed that modes are uncoupled, in that each responds independently of the excitation level of other modes. This assumption is derived from the belief that, while modal coupling generally exists in physical structures, its effects are relatively small and negligible. This practice is reinforced by the fact that the actual causes of modal coupling are poorly understood and difficult to model. To that end, this work attempts to isolate and fit a model to the effects of modal coupling in experimental data from a nonlinear structure. After performing a low-level test to determine the linear natural frequencies and damping ratios of several modes, sine beat testing is used to individually excite each mode and record its nonlinear dynamic response. The Restoring Force Surface (RFS) method is then implemented to fit a nonlinear model to each isolated modal response. Sine beats are then done on multiple modes simultaneously, in which the response is assumed to be a combination of the nonlinear models of each isolated mode and some coupling term between them. As the terms modeling the individual modes are known, the only unknown is the coupling term. This procedure is performed on several mode pairs and excitation levels to evaluate the effectiveness of all proposed coupling models and gauge the significance of modal coupling in the structure.
Influence of library relocation and marketing: examining zip codes and health disparities to serve consumers in East Tennessee

Background: In 2014, the Preston Medical Library underwent a radical change, moving from an academic office building to the main floor of a regional medical center. While the library had previously served the public, health information requests have substantially increased in volume due to the new location. Researchers analyzed request data to see if the service’s reach has expanded to counties that previously had not used the service, to see which counties have requested the most health information, and to ascertain whether more requests are from counties with higher poverty rates. Case Presentation: Each health information request is logged with the subject nature and patron contact information. Consumer health request data were downloaded from the library database. Names and other identifying data were removed. Request forms were sorted and reviewed by zip code and county, comparing number of requests as well as poverty levels. Tableau was utilized to create maps, visually showing patron concentrations and poverty levels. Conclusions: There were 3,141 health information requests from September 21, 2014, to May 31, 2019. The majority of requests were from local counties. Requests were also received from counties that had not been previously reached and counties with elevated poverty levels. Collecting data on patron interactions is not only critical for institutional reporting, but also for community outreach. Understanding that data require taking additional steps to filter the information, assess local demographics, and customize library services. Researchers anticipate being able to better tailor services to the community based on the results.
A stochastic model for the aerodynamics of irregularly shaped gravel

Abstract The flight of compact debris can be highly stochastic in nature. However, standard flight equations are deterministic after assuming a spherical shape for gravel. This study proposes a stochastic model to resolve some key aspects of these uncertainties that originate due to changes in orientation of the debris particle during flight. The model numerically solves the differential equations of motion for a large number of gravel pieces taken from five different size gradations. The amount by which the drag and lift coefficients ( δ C D and δ C L ), the lift force direction ( δ θ ) and the projected area ( δ α ) are varied at each time-step during the flight simulation of a single debris are the four parameters used to fit the model to the results obtained from gravel drop experiments. An optimization criterion ( e ) was introduced and the model was optimized for each gravel gradation tested. It was found that only small perturbations in the lift coefficient are needed to model the flight. However, larger perturbations in the direction of the lift force are required to correctly predict the statistics of the landing locations.
Pivotal Roles for Ribonucleases in Streptococcus pneumoniae Pathogenesis

ABSTRACT RNases perform indispensable functions in regulating gene expression in many bacterial pathogens by processing and/or degrading RNAs. Despite the pivotal role of RNases in regulating bacterial virulence factors, the functions of RNases have not yet been studied in the major human respiratory pathogen Streptococcus pneumoniae (pneumococcus). Here, we sought to determine the impact of two conserved RNases, the endoribonuclease RNase Y and exoribonuclease polynucleotide phosphorylase (PNPase), on the physiology and virulence of S. pneumoniae serotype 2 strain D39. We report that RNase Y and PNPase are essential for pneumococcal pathogenesis as both deletion mutants showed strong attenuation of virulence in murine models of invasive pneumonia. Genome-wide transcriptomic analysis revealed that nearly 200 mRNA transcripts were significantly up-regulated, whereas the abundance of several pneumococcal sRNAs, including the Ccn (CiaR Controlled Noncoding RNA) sRNAs, were altered in the Δrny mutant relative to the wild-type strain. Additionally, lack of RNase Y resulted in pleiotropic phenotypes that included defects in pneumococcal cell morphology and growth in vitro. In contrast, Δpnp mutants showed no growth defect in vitro, but differentially expressed a total of 40 transcripts including the tryptophan biosynthesis operon genes and numerous 5’-cis-acting regulatory RNAs, a majority of which were previously shown to impact pneumococcal disease progression in mice using the serotype 4 strain TIGR4. Altogether our data suggest that RNase Y exerts a global impact on pneumococcal physiology, while PNPase-mediates virulence phenotypes, likely through sRNA regulation. IMPORTANCE Streptococcus pneumoniae is a notorious human pathogen that adapts to conditions in distinct host tissues and responds to host cell interactions by adjusting gene expression. Ribonucleases (RNases) are key players that modulate gene expression by mediating the turnover of regulatory and protein-coding transcripts. Here, we characterized two highly conserved RNases, RNase Y and PNPase, and evaluated their impact on the S. pneumoniae transcriptome for the first time. We show that PNPase influences the levels of a narrow set of mRNAs, but a large number of regulatory RNAs primarily implicated in virulence control, whereas RNase Y has a more sweeping effect on gene expression, altering levels of transcripts involved in diverse cellular processes including cell division, metabolism, stress response, and virulence. This study further reveals that RNase Y regulates expression of genes governing competence by mediating the turnover of CiaR-controlled-noncoding (Ccn) sRNAs.
Effect of chemically altered and modified-live infectious bovine rhinotracheitis vaccines on fetal retention in beef replacement heifers during the first four months of gestation

The objective of this study was to determine whether vaccination of pregnant heifers with either chemically altered or modified live infectious bovine rhinotracheitis (IBR) vaccine would cause abortion when previously vaccinated with a chemically altered IBR vaccine. During pre-weaning processing and at weaning, 202 crossbred Brangus heifers were administered chemically altered infectious bovine rhinotracheitis virus (IBR) vaccines. At 60 to 120 days of gestation after first fall breeding, heifers were administered either a modified live virus (MLV) or a chemically altered IBR vaccine. Heifers at 60 to 90 days gestation, and those greater than 90 and up to 120 days gestation, were assigned by gestation category to one of three treatments: (1) a single IM injection of chemically altered IBR vaccine; (2) a single IM injection of modified live IBR vaccine; or (3) controls - no injections. Heifers were palpated 56 days after treatment to determine potential fetal loss. Subsequent calving information was used to confirm post-treatment palpation data. One heifer in each group aborted after treatment; these numbers did not differ among treatments (p=1.0) nor between gestation categories (p=1.0). Calving numbers verified that no fetuses were lost after post-treatment palpation. We concluded that a single dose of these vaccines in pregnant replacement heifers did not cause increased abortion rates compared to unvaccinated control heifers.
Improved delayed detached eddy simulation of a porous wavy trailing edge

This paper proposes a novel trailing-edge treatment to reduce trailing-edge noise. Prior studies showed that both porous materials and wavy trailing edges have decent trailing-edge noise reduction. Therefore, a combination of porosity and waviness, or a porous wavy trailing edge, could possibly result in greater noise reduction. Improved delayed detached eddy simulations are performed to compare the aeroacoustic performance of a porous wavy trailing edge to those of clean airfoil, porous trailing edge, and wavy trailing edge. It is revealed that a porous wavy trailing edge reduces the overall sound pressure level by 8.1 dB without compromising the aerodynamic efficiency. The detailed flow physics of noise reduction with a porous wavy trailing edge is also investigated. Overall, the current research provides a low-noise solution for wind turbines and the future's ultra-quiet aircraft.
Parton shower effects in $t\bar{t}W^\pm$ production at NLO QCD

We present a selection of results from our recent study of $pp\to t\bar{t}W^\pm$ production matched to partons showers at NLO QCD at the LHC. Theoretical predictions are obtained at perturbative orders $\mathcal{O}(\alpha_s^3\alpha)$ and $\mathcal{O}(\alpha_s\alpha^3)$, where the different contributions are studied first separately at the inclusive level before being combined within a realistic two same-sign lepton signature. We investigate in detail uncertainties originating from missing higher-order corrections and from the parton-shower matching scheme employed.
Oxygen Delivery to the Retina and Related Visual Pathology

The survival of the retina and optic nerve is dependent on an adequate supply of oxygen and nutrients to fuel the metabolic processes that are vital for tissue homeostasis and primary visual function. Ocular diseases that affect the retina, including diabetic retinopathy, retinopathy of prematurity, glaucoma, and numerous proliferative retinopathies, are devastating diseases leading to major vision loss in humans. While the etiologies of these diseases are different, abnormalities in the delivery and consumption of oxygen are thought to be significant in all of them. Despite this common factor, quantitative studies that adequately correlate disease progression with changes in retinal oxygenation are lacking. In part, this is due to the almost complete absence of instrumentation for monitoring oxygenation in humans and the relatively few animal models that exhibit the full pathophysiology of these different retinal diseases.
Microbial Biomass and Utilization of Dissolved Organic Matter in the Okefenokee Swamp Ecosystem

The Okefenokee Swamp exhibited levels of microbial biomass and aerobic glucose uptake comparable to those of other organically rich, detritus-based aquatic ecosystems. In contrast to other peat-accumulating systems, this acidic (pH 3.7), low-nutrient environment does not show diminished water column or surface sediment microbial biomass or heterotrophic activity. The total particular ATP varied between 0.03 and 6.6 μg liter−1 (mean, 1.6 μg liter−1) in water and between 1 and 28 μg g (dry weight)−1 (mean, 10.0 μg g [dry weight]−1 in sediments. The turnover times for dissolved d-glucose were 1.26 to 701.25 h (mean, 110.25 h) in aerobic waters and 2.4 to 72 min (mean, 10.2 min) in aerobic surface sediments. Water column bacterial secondary production, measured as the incorporation of [3H]thymidine into cold-trichloroacetic acid-insoluble material, ranged from 0.06 to 1.67 nmol liter−1 day−1 (mean, 0.45 nmol liter−1 day−1). The kinetics of d-glucose uptake by water column microflora are multiphasic and suggest the presence of a diverse microbial population capable of using labile substrates at nanomolar concentrations and at substantial rates. The presence of a large and active aerobic microbial community in the Okefenokee Swamp is indicative of an important role for microbes in swamp geochemistry and strongly suggests the existence of a detritus-based food web.
Use of Intrathecal Antibiotic Administration for Treatment of CNS Infections in a Neuro-ICU: A Case Series (P6.033)

BACKGROUND: Intraventricular central nervous system (CNS) infections possess a significant associated morbidity and mortality. There are multiple conflicting opinions as to the relevance of intrathecal (IT) antibiotics, particularly regarding the benefit versus potential harm associated with the side effects of administration. OBJECTIVE: We present a review of ten cases of use of IT antibiotics for management of intraventricular infections. METHODS: Retrospective case series of patients who received IT antibiotics in combination with systemic antibiotics for treatment of intraventricular infection over the past 8 years. RESULTS: Ten patients received IT antibiotic therapy for CNS infection. Admitting diagnoses included head trauma, subarachnoid hemorrhage (SAH), infected ventriculoperitoneal shunt, entrapped 4 th ventricle after old SAH and multiple shunt revisions, mastoiditis with brain abscess, surgical site abscess with meningitis and ventriculitis, and 4 patients with intracranial hemorrhage. All patients received external ventricular drainage (EVD) devices during or prior to transfer to our unit. Mean time from hardware placement to first positive CSF culture was 17.3 days (range 0-65 days). Pathogens cultured from CSF: A.baumannii (3 patients), K.pneumonia (2 patients), Vancomycin-Resistant E.faecalis (2 patients), S.marcens (1 patient), Group A strep (1 patient), and Methicillin-Resistant S.aureus (1 patient). Intrathecally instilled antibiotics included colistin, streptomycin, tobramycin, gentamicin, and vancomycin. Average time to CSF culture clearance was 4.4 days (range 1-11 days in 9 patients) after initiation of intrathecal antibiotics. 1 patient died before CSF cleared. No patients experienced significant side effects attributed to IT antibiotic administration. Mean modified Rankin scale on discharge was 4.75 (range 2-5). One patient is still currently hospitalized. Five patients died due to their underlying medical condition. CONCLUSIONS: We report IT antibiotic therapy as an adjunct for treating CNS infections. Average CSF clearance occurred within 4.4 days of treatment initiation, without significant side effects. Further studies are warranted to support our findings. Disclosure: Dr. Mehta has nothing to disclose. Dr. Jones has nothing to disclose. Dr. Ruiz Cuero has nothing to disclose. Dr. Abdelhak has nothing to disclose. Dr. Rehman has nothing to disclose. Dr. Wellwood has nothing to disclose. Dr. Lasak-Myall has nothing to disclose. Dr. Varelas has received personal compensation for activities with UCB Pharma as an advisory board member.
Infrared measurements of BrO (X2Π32)

The v = 1-0 band of BrO in the X2Π32 spin state was measured using high-resolution Fourier transform absorption spectroscopy. One hundred and thirty transitions were assigned and analyzed to determine the band origins, rotational constants, and distortion constants for both 79BrO and 81BrO. The v = 1-0 band strength was determined to be 5.04 ± 0.80 cm−2 atm−1 using a Herman-Wallis type analysis. The A2Π-X2Π transition of BrO was measured in the region 285 to 355 nm simultaneously with the infrared measurements with a diode array spectrometer. UV absorption cross sections of the A2Π-X2Π transition were determined relative to the calculated IR intensities. The absorption cross section at the peak of the (7, 0) band at 338.5 nm is (1.4 ± 0.3) × 10−17 cm2 molecule−1 at 298 K.
mPGES-1 as a target for cancer suppression: A comprehensive invited review "Phospholipase A2 and lipid mediators".

Prostaglandin E2 (PGE2) is a bioactive lipid that can elicit a wide range of biological effects associated with inflammation and cancer. The physiological roles of PGE2 are diverse, mediated in part through activation of key downstream signaling cascades via transmembrane EP receptors located on the cell surface. Elevated levels of COX-2 and concomitant overproduction of PGE2 are often found in human cancers. These observations have led to the use of non-steroidal anti-inflammatory drugs (NSAIDs) as chemopreventive agents, particularly for colorectal cancer (CRC). Their long-term use, however, may be associated with gastrointestinal toxicity and increased risk of adverse cardiovascular events, prompting the development of other enzymatic targets in this pathway. This review will focus on recent efforts to target the terminal synthase, mPGES-1, for cancer chemoprevention. The role of mPGES-1 in the pathogenesis of various cancers is discussed. In addition, an overview of recent efforts to develop small molecule inhibitors that target the protein with high selectivity is also be reviewed.
Physicians “Missing in Action”: Family Perspectives on Physician and Staffing Problems in End‐of‐Life Care in the Nursing Home

Objectives: To understand the roles of physicians and staff in nursing homes in relation to end-of-life care through narrative interviews with family members close to a decedent. Design: Qualitative follow-up interviews with 54 respondents who had participated in an earlier national survey of 1,578 informants. Setting: Brown University interviewers conducted telephone interviews with participants throughout the United States. Participants: The 54 participants agreed to a follow-up qualitative interview and were family members or close to the decedent. Measurements: A five-member, multidisciplinary team to identify overarching themes taped, transcribed, and then coded interviews. Results: Respondents report that healthcare professionals often insufficiently address the needs of dying patients in nursing homes and that “missing in action” physicians and insufficient staffing create extra burdens on dying nursing home residents and their families. Conclusion: Sustained efforts to increase the presence of physicians and improve staffing in nursing homes are suggested to improve end-of-life care for dying residents in nursing homes.
Twelve novel microsatellite markers for the Great Plains toad, Bufo cognatus

Here I report on 12 microsatellite loci designed for populations of the Great Plains toad (Bufo cognatus) in the deserts of the southwestern USA. Diversity at these loci measured for 134 individuals from four breeding aggregations was relatively high with seven to 34 alleles per locus (mean = 17.8). Observed heterozygosities ranged from 0.444 to 0.949 and expected heterozygosities ranged from 0.597 to 0.951. These markers will be useful for studies of population genetic structure, parentage and relatedness in this explosively breeding amphibian.
Analysis of the self-excited subband coder: a new approach to medium band speech coding

A speech coding technique is introduced for bit rates below 10 kb/s. The coder exploits the frequency-domain properties of aural perception that are associated with subband coding and uses the block coding techniques which have recently been used to great advantage in low-rate full-band coders such as the self-excited vocoder and the code-excited linear predictive coder. The coder contains an analysis/synthesis system for decomposing the speech into contiguous frequency bands and merging the bands in reconstruction. The coding of the individual subbands is accomplished by using long-term predictors to represent channel outputs. Various configurations of the analysis/synthesis structure and the self-excitation model are considered. Issues related to the analysis procedure, the performance and the system efficiency are discussed. >
The role of the regulator-gene product (repressor) in catabolite repression of β-galactosidase synthesis in Escherichia coli

1. The specific role of the lac repressor (i-gene product) in transient catabolite repression evoked by the introduction of glucose into the medium has been investigated in Escherichia coli by using mutants of the i-gene. 2. A temperature-sensitive mutant (iTL) is normally inducible and demonstrates transient repression when grown at 32°. At 42° it is about 20% constitutive and transient catabolite repression is abolished. 3. A strain carrying an amber suppressor-sensitive mutation in the i-gene is phenotypically constitutive and also fails to show transient catabolite repression. 4. Insertion of Flaci+ into this strain restores both inducibility and transient repression. 5. It is concluded that the i-gene product interacts with the catabolite co-repressor in such a way that its affinity for the operator is increased.
Stent Induced Changes to the Radius of Curvature of the Cerebrovasculature

Stent implantation has expanded the endovascular treatment of intracranial aneurysms to those with widenecks, that were previously unfavorable to coil embolization. Past studies have found that several mechanisms including stent-induced endothelization and hemodynamic changes due to alteration in vessel geometry may contribute to stable clot formation within the aneurysmal sac and aid in aneurismal healing [1,2]. Change in the angle of the parent arteries after stent-assisted coil embolization of anterior communicating artery (Acom) aneurysms has been measured on projection angiograms; however, use of 2D angiographic datasets to describe changes of vessel angle in 3D may result in significant error. The goal of this study was to quantitatively characterize the change in the radius of curvature (RC) of the parent artery induced by the implantation of an intracranial stent in 3D.Copyright © 2012 by ASME
DNA target sequence identification mechanism for dimer-active protein complexes

Sequence-specific DNA-binding proteins must quickly and reliably localize specific target sites on DNA. This search process has been well characterized for monomeric proteins, but it remains poorly understood for systems that require assembly into dimers or oligomers at the target site. We present a single-molecule study of the target-search mechanism of protelomerase TelK, a recombinase-like protein that is only active as a dimer. We show that TelK undergoes 1D diffusion on non-target DNA as a monomer, and it immobilizes upon dimerization even in the absence of a DNA target site. We further show that dimeric TelK condenses non-target DNA, forming a tightly bound nucleoprotein complex. Together with theoretical calculations and molecular dynamics simulations, we present a novel target-search model for TelK, which may be generalizable to other dimer and oligomer-active proteins.
The pathology of preclinical medullary thyroid carcinoma.

Medullary carcinoma of the thyroid (MTC) occurs sporadically, or in familial forms in familial medullary thyroid carcinoma and multiple endocrine neoplasia types 2A and 2B. In the familial forms it is associated with well-characterized, germline mutations in the RET protooncogene. The mutation sites differ in MEN2A and MEN2B, and MTC develops at an earlier age and is more aggressive in MEN2B. Screening of relatives of affected individuals for such mutations can identify those at risk of developing MTC and total thyroidectomy can be carried out in the first decade of life before the development of clinical disease. Analysis of such removed thyroid glands shows abnormalities of the parafollcular C-cells in almost all cases. The abnormalities range from C-cell hyperplasia, either diffuse or nodular, to microcarcinoma and occasionally frank MTC. The abnormalities are bilateral and affects the upper two thirds of the thyroid lobes. Microcarcinomas may be visible with the naked eye, but often they are identified only on microscopy. Histopathological examination of the entire gland is essential.
The utilization of z-domain models in the noise analysis of switched-capacitor filters

The paper describes the analytical evaluation of the sample-and-hold noise component in switched-capacitor filters. Both the switch noise and amplifier white noise components are modelled with the aid of z-domain building blocks for lower-order systems. As an alternative, nodal charge equations are used for higher-order structures. These may be obtained by inspection and are conveniently represented by a general ‘noise-free’ set. Noise terms are then added to the array when evaluating specific transfer functions. The procedures are illustrated by application to both a biquad and a seventh-order leapfrog structure. Predictions of noise output show excellent agreement with practical results obtained from scaled-capacitor breadboard and fabricated chip realizations.
Correlation imaging for multiscan MRI with parallel data acquisition

A new approach to high-speed magnetic resonance imaging (MRI) that uses all the data acquired in a multiscan imaging session is presented. This approach accelerates MRI data acquisition by statistically estimating correlation functions from images with different contrast and/or resolution. In multiscan MRI with parallel data acquisition, the estimation of correlation functions is dynamically improved as imaging proceeds. This allows imaging acceleration factors to be increased in subsequent scans, thereby reducing the total time of a multiscan MRI protocol. Furthermore, the correlation function estimates bring information about both coil sensitivity and anatomical structure into image reconstruction, thereby offering the ability to speed up MRI beyond the parallel imaging acceleration limit posed by a coil array alone. In this study, the feasibility of correlation imaging is demonstrated experimentally using brain and spine imaging protocols. The ability of correlation imaging to achieve an aggregate acceleration factor in excess of the number of coil elements in the phase encoding direction is also demonstrated. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Comparison between Experiential and Didactic Methods of Death Education

This research examined the impact of a death and dying workshop on individual attitudes toward life and death. The workshop was a voluntary eight-hour, small group experience conducted for heteroge...
Quantitative gel electrophoresis of DNA: Resolution of overlapping bands of restriction endonuclease digests

Accurate quantitation of the distribution of DNA digested to completion by a restriction endonuclease and separated in an electrophoretic gel is greatly facilitated by electronic imaging systems employing charge-coupled device detectors. Such quantitation permits the extraction of more accurate values of the lengths of both the parent molecular species and the fragments produced by a restriction endonuclease. We describe a method that determines the number of components in bands containing two or more daughter fragments that are of similar length and hence not resolved by gel electrophoresis. We also report a constrained deconvolution procedure based on the equal number of daughter molecules in a terminal digestion by a restriction endonuclease that resolves the distribution of each of the overlapping species in a composite band on a gel and hence increases the accuracy of the lengths assigned to each.
Angioscopic visualization of blood vessel interior in animals and humans.

The purpose of this study is to describe the use of angioscopes in flowing bloodstreams of animals and humans, to demonstrate the ability to precisely deliver laser energy to an intravascular target using visual guidance and to determine the information content and spatial content of angioscopy. Angioscopy was performed in 5 living dogs, 16 cadaver vascular segments, and 14 patients at the time of peripheral or coronary bypass surgery. Five canine femoral artery segments received angioscopically directed intravascular Nd: YAG laser irradiation. We were able to precisely direct the laser irradiation to predetermined intimal targets. Gross tissue injury varied from none to carbonization and vascular perforation, depending on incident energy. Using a variety of flexible fiberoptic endoscopes ranging in diameter from 1.5 to 3.7 mm, we were able to visualize intravascular structures including plaque, suture lines, venous valves, and thrombi in living patients. No patient incurred complications of any sort. We conclude that angioscopy using flexible en doscopes can be performed safely, can provide clinically useful information, and may provide a means for delivering visually directed intravascular laser irradiation.
On Learning Processes and the National Mathematics Advisory Panel Report

This article is a response to Foundations for Success: The Final Report of the National Mathematics Advisory Panel (2008) and to one of the task group reports on which it was based, the report of the Task Group on Learning Processes. The author uses Maxwell’s two views of causality—regularity and process—to explore three major issues raised in the report: the nature of what is learned, how learning occurs, and the transfer of learning. She proposes alternative recommendations to those offered by the Panel, by drawing upon the mathematics education literature, which was largely excluded from the reviewed research. Furthermore, by neglecting research grounded in a process view of causality, the report excludes perspectives and findings that would have illuminated what it means to develop conceptual understanding in mathematics—one of three valued outcomes cited by the Panel.
Photodynamic therapy in China: Over 25 years of unique clinical experience: Part One—History and domestic photosensitizers

Photodynamic therapy (PDT) was started in the People's Republic of China in the early 1980s after domestically produced hematoporphyrin derivative (HpD) became available. Since then, numerous photosensitizers have been synthesized and evaluated. Several promising ones have undergone clinical investigations and a few have entered into formal clinical trials. Various lasers and non-coherent light sources have been developed in China to facilitate domestic photosensitizers and clinical PDT applications. Chinese pioneered PDT protocols for treating nasopharyngeal carcinoma, liver carcinoma, port-wine stains (PWS) and urethral condylomata acuminata. Over the past 25 years Chinese physicians have treated several thousands patients, gained substantial experience in both basic sciences and clinical applications, and generated a great number of clinical reports. PDT related research and clinical activities would most likely continue to grow in China. The Part One of this article provides an overview on China's PDT history and domestic photosensitizers. Clinical PDT data of nasopharyngeal carcinoma, liver cancer and port-wine stains will be discussed in the Part Two of this article.
An application of Cheng's lemma for minimizing the asymptotic variance of best asymptotically normal estimators based on sample quantiles

Abstract A method is given for determining the optimal spacings of best asymptotically normal (BAN) estimators when estimating the real parameter θ of a density ƒ(x; θ) from sample quantiles. This method is based on a lemma due to Cheng (1975). Although originally used to find optimal spacings for a location or scale parameter θ, it is shown that Cheng's lemma can also be used to find optimal spacings for non-location, non-scale parameters, under certain conditions. In particular, Cheng's lemma can be applied to certain families of densities with monotone likelihood ratio in X. The optimal spacings for estimating the parameters of the linear failure rate distribution are calculated.
Antibiotic Resistance: How Much Do We Know and Where Do We Go from Here?

The rapid dissemination of antibiotic resistant (ART) pathogens threatens human health and may have significant social and financial impacts. It is well recognized that applications of antibiotics in human clinical therapy, aquaculture, and food animal production all contribute to the emergence and
Influence of Administered Indigenous Microorganisms on Uptake of [Iodine-125] γ-Globulin In Vivo by Intestinal Segments of Neonatal Calves

Abstract Ten calves less than 14h of age (average 8.6h) were anaesthetized, and the intestine was ligated into segments 10cm in length at 3-cm intervals beginning 1.8m anterior to the ileocecal junction and proceeding proximally. Seven treatments were assigned in random order to segments in three successive sections of the small intestine. Segments received 1ml of viable bacteria of intestinal origin, autoclaved bacteria of intestinal origin, or sterile microbiological broth at zero time; then after 4h they were injected with iodine-125 labeled γ -globulin. After an additional 1.5h, the experiment was ended and uptake assayed. Two treatments measured anaerobic microbial growth after 4h incubation with 1ml of either sterile broth or live bacteria culture. Residual [iodine-125] γ -globulin was measured in segments receiving 1ml of sterile broth or live bacteria culture with 5.5-h incubation followed by 15-s exposure to labeled γ -globulin. Uptake was lowest in segments receiving live bacteria as compared to segments receiving sterile inocula. Number of bacteria per gram of tissue was correlated negatively with uptake. Low corticosteroids in serum were associated with low uptake of γ -globulin.
The effect of isometric exercise upon the strength of antagonistic muscles.

1. Training of the elbow flexors by maximal isometric exercise produced a significant increase in the strength of their antagonists. 2. There was no difference in the amount of strength increase at any of the three measured points in the arc of movement.
Increased Memory Load-Related Frontal Activation after Estradiol Treatment in Postmenopausal Women

Prior research shows that menopause is associated with changes in cognition in some older women. However, how estrogen loss and subsequent estrogen treatment affects cognition and particularly the underlying brain processes responsible for any cognitive changes is less well understood. We examined the ability of estradiol to modulate the manipulation of information in working memory and related brain activation in postmenopausal women. Twenty healthy postmenopausal women (mean age (SD) = 59.13 (5.5)) were randomly assigned to three months of 1 mg oral 17-β estradiol or placebo. At baseline and three months later each woman completed a visual verbal N-back sequential letter test of working memory during functional magnetic resonance imaging (fMRI). The fMRI data showed that women who were treated with estradiol for three months had increased frontal activation during the more difficult working memory load conditions compared to women treated with placebo. Performance on the verbal working memory task showed no difference between estradiol and placebo treated subjects. These data are consistent with prior work showing increases in frontal activation on memory tasks after estrogen treatment. However, this is the first study to show that estrogen-induced increases in brain activity were tied to cognitive load during a verbal working memory task. These data suggest that estradiol treatment effects on cognition may be in part produced through modulation of frontal lobe functioning under difficult task conditions.
Fractionation of the gene-size macronuclear chromatin fragments of the binucleated eukaryote Oxytricha.

The macronuclear chromatin of Oxytrichia nova consists of chromatin fragments which are fully soluble in 0.2 mM EDTA and whose DNA length varies from 500–25 000 bp. The DNA migrates electrophoretically as a series of discrete bands, with specific genes present in only one or a few bands. The chromatin fragments are composed of nucleosomes and migrate electrophoretically in proportion to their DNA length. These results suggest schemes for the fractionation of undigested chromatin in order to enrich for specific genes, facilitating analysis of changes in chromatin structure associated with changes in gene expression.
Continuous-flow fast atom bombardment mass spectrometry of oligonucleotides

Although frit-fast atom bombardment (frit-FAB) and continuous-flow FAB mass spectrometry have become standard methods for the analysis of peptides and peptide mixtures, these techniques have not been applied previously to the analysis of oligonucleotides. Mobilephase composition, flow rate, and sample size were optimized for the analysis of oligonucleotides by negative ion frit-FAB mass spectrometry (a type of continuous-flow FAB mass spectrometry). With a mobile phase consisting of methanol/water/triethanolamine (80:20:0.5, v/v/w), flow injection frit-FAB analysis of oligonucleotides showed lower limits of detection compared to standard probe FAB mass spectrometry. For example, in order to obtain a signal-to-noise ratio of 3:1, 38 prnol of d(GTIAAC) were required for frit-FAB mass spectrometry and 62 pmol were required for standard probe FAB mass spectrometry. The largest difference between frit-FAB and standard probe FAB was observed for d(pC)5, for which the limit of detection by frit-FAB was approximately 11-fold lower than by standard FAB mass spectrometry. Adjustment of the mobile phase to pH 7 with trifluoroacetic acid increased the limit of detection (reduced sensitivity) a minimum of sixfold. Equimolar mixtures of two or three oligonucleotides produced deprotonated molecules in identical relative abundances whether analyzed by frit-FAB or standard probe FAB mass spectrometry. Finally, frit-FAB liquid chromatography mass spectrometry was demonstrated by separating mixtures of oligonucleotides on a β -cyclodextrin high-performance liquid chromatography column with a mobile phase containing methanol, water, and triethanolamine.