cssi/SciSciGPT-SciSciNet huggingface dataset:
Investigation of changes in tetracycline repressor binding upon mutations in the tetracycline operator

The tetracycline operon is an important gene network component, commonly used in synthetic biology applications because of its switch-like character. At the heart of this system is the highly specific interaction of the tet repressor protein (TetR) with its cognate DNA sequence (tetO). TetR binding on tetO practically stops expression of genes downstream of tetO by excluding RNA polymerase from binding the promoter and initiating transcription. Mutating the tetO sequence alters the strength of TetR-tetO binding and thus provides a tool to synthetic biologists to manipulate gene expression levels. We employ molecular dynamics (MD) simulations coupled with the free energy perturbation method to investigate the binding affinity of TetR to different tetO mutants. We also carry out in vivo tests in Escherichia coli for a series of promoters based on these mutants. We obtain reasonable agreement between experimental green fluorescent protein (GFP) repression levels and binding free energy differences computed from molecular simulations. In all cases, the wild-type tetO sequence yields the strongest TetR binding, which is observed both experimentally, in terms of GFP levels, and in simulation, in terms of free energy changes. Two of the four tetO mutants we tested yield relatively strong binding, whereas the other two mutants tend to be significantly weaker. The clustering and relative ranking of this subset of tetO mutants is generally consistent between our own experimental data, previous experiments with different systems and the free energy changes computed from our simulations. Overall, this work offers insights into an important synthetic biological system and demonstrates the potential, as well as limitations of molecular simulations to quantitatively explain biologically relevant behavior.
Effect of Temperature on Clove Oil Anesthesia in Steelhead Fry

Abstract The effects of temperature (11, 15, and 20°C) on clove-oil-induced anesthesia in fry of steelhead Oncorhynchus mykiss (0.18 ± 0.01 g [mean ± SE]) were evaluated at 25, 50, and 100 mg clove oil/L. Induction time decreased significantly with increasing temperature and dose. Recovery time after removal from anesthesia decreased significantly with increasing temperature. Mortality at 24 h postanesthesia increased significantly with increasing temperature and dose. Although clove oil appears to be an effective general anesthetic for salmonid fry, the data indicate that care must be taken in determining the appropriate dose to minimize temperature-associated mortality.
Excitation and desensitization of mouse rod photoreceptors in vivo following bright adapting light

Electroretinographic (ERG) methods were used to determine response properties of mouse rod photoreceptors in vivo following adapting illumination that produced a significant extent of rhodopsin bleaching. Bleaching levels prevailing at ∼10 min and ∼20 min after the adapting exposure were on average 14% and 9%, respectively, based on the analysis of visual cycle retinoids in the eye tissues. Recovery of the rod response to the adapting light was monitored by analysing the ERG a-wave response to a bright probe flash presented at varying times during dark adaptation. A paired-flash procedure, in which the probe flash was presented at defined times after a weak test flash of fixed strength, was used to determine sensitivity of the rod response to the test flash. Recovery of the response to the adapting light was 80% complete at 13.5 ± 3.0 min (mean ±s.d.; n= 7) after adapting light offset. The adapting light caused prolonged desensitization of the weak-flash response derived from paired-flash data. By comparison with results obtained in the absence of the adapting exposure, desensitization determined with a test-probe interval of 80 ms was ∼fourfold after 5 min of dark adaptation and ∼twofold after 20 min. The results indicate, for mouse rods in vivo, that the time scale for recovery of weak-flash sensitivity substantially exceeds that for the recovery of circulating current following significant rhodopsin bleaching. The lingering desensitization may reflect a reduced efficiency of signal transmission in the phototransduction cascade distinct from that due to residual excitation.
Physical activity and mortality in women in the Framingham Heart Study

Abstract Men who are more active live longer, but it is not clear if the same is true for women. We monitored 1404 women aged 50 to 74 who were free of cardiovascular disease. We assessed physical activity levels and ranked subjects into quartiles. After 16 years, 319 (23%) women had died. The relative risk of mortality, compared to the least active quartile, was as follows: second quartile, 0.95 (95% confidence interval [Cl] 0.72 to 1.26); third quartile, 0.63 (95% Cl 0.46 to 0.86); most active quartile, 0.67 (95% Cl 0.48 to 0.92). The relative risks were not changed by adjustment for cardiac risk factors, chronic obstructive pulmonary disease, or cancer or by excluding all subjects who died in the first 6 years (to eliminate occult disease at baseline). There was no association between activity levels and cardiovascular morbidity or mortality. We conclude that women who were more active lived longer; this effect was not the result of decreased cardiovascular disease.
Motor fluctuations and dyskinesias in advanced/end stage Parkinson's disease: a study from a population of brain donors.

Treatment-related motor fluctuations (MFs) and dyskinesias are considered one of the most important problems in the long-term management of Parkinson’s disease (PD). However, only a few studies have focused on their characteristics during advanced and end stages of the disease. We therefore assessed MFs and dyskinesias in a cohort of 61 late/end stage patients with a clinical and pathological diagnosis of PD and investigated the influence of disease- and treatment-related variables on their occurrence. A total of 62.3% of our patients experienced “wearing-off” phenomena, 68.9% “on-off” motor fluctuations and 60.7% dyskinesias at advanced/end stage disease. Age at disease onset and disease duration were significantly associated with dyskinesias. A substantial number of patients experienced spontaneous resolution of their motor complications during the last two years of their disease without treatment modifications.
Radical prostatectomy for the patient with locally advanced prostate cancer.

The proper management of patients with locally advanced adenocarcinoma of the prostate has been contentious and too frequently based on antiquated misconceptions. Nonextirpative treatments, even when combined with neoadjuvant hormonal therapy, are inferior to the surgical removal of the prostate for controlling local progression and distant dissemination of the cancer. Radical prostatectomy combined with early adjunctive hormonal therapy for patients with nodal metastasis is superior to all other forms of therapy and should be considered the standard of care. This approach provides survival rates comparable with patients with clinically organ-confined prostate cancer.
Summary and Conclusions: New Perspectives in Hereditary Angioedema: Molecular Mechanisms and Therapeutic Choices: A CME Symposium Presented at the World Allergy Congress, Buenos Aires, Argentina (December 2009).

Hereditary angioedema (HAE) is a relatively rare disease, with an estimated prevalence of approximately 1 per 50,000 in the general population. Despite its rarity, HAE has become an area of intense interest within the medical community. This interest likely reflects several different aspects of HAE, including: the high potential for significant morbidity and mortality associated with attacks of angioedema in HAE patients, the frequent failure to make an accurate and timely diagnosis, the progress in unraveling the underlying pathophysiology of HAE, and the tremendous advances in treatment options. To limit the morbidity and mortality that has long afflicted patients with HAE, it has become increasingly important that the clinician understand both the underlying mechanisms of swelling in HAE and the newer treatment strategies that have been developed for HAE. This supplement contains 3 reviews that summarize the current state-of-the-art regarding the pathophysiology and treatment of HAE.
The Effect of Material Constitutive Models on Stress Wave Propagation Calculations

Material models which have been successfully used for describing experimental observations of stress wave propagation in metals, polymers, composites, and porous materials are used in a series of one-dimensional finite-difference calculations of stress pulses propagating in a semi-infinite medium. These calculations show the effect of the material model on pulse attenuation. Parametric variations indicate the sensitivity of the attenuation to the parameters of each model. A simple conceptual description based on the hysteretic energy loss experienced by the material in a loading-unloading cycle is used to explain the results. Relevance of the results to the prediction of damage in specific engineering design calculations is developed. The results and conceptual description should aid the stress analyst in assessing which effects to include in the material model used in specific multidimensional calculations.
Secondary traumatic stress in nurses: a systematic review.

Background Is there a “cost of caring” for health care providers of traumatized patients? Objectives The aim of this study is to review the literature on secondary traumatic stress in nurses in order to answer the following questions: What studies have been conducted on secondary traumatic stress in nurses in all clinical specialties? What instruments were used to measure secondary traumatic stress in nurses and what psychometric properties were reported? Design A systematic review. Data Sources CINAHL, PubMed, and PsycINFO databases were searched for the years 1981 to the present. Keywords used in the database searches included secondary traumatic stress , compassion fatigue , vicarious traumatization , secondary trauma , PTSD , and nurses . Review Methods Research studies were reviewed for the following inclusion criteria: the sample included nurses, the secondary traumatic stress symptoms were measured, and the language was English. Results Seven studies were found in which researchers examined secondary traumatic stress in nurses. The samples in five of these studies consisted of all nurses, whereas in the remaining two studies, nurses were included in the samples but the results were not specifically reported for the subgroup of nurses. Presence of secondary traumatic stress was reported in forensic nurses, emergency department nurses, oncology nurses, pediatric nurses, and hospice nurses. Three instruments were identified that measured secondary traumatic stress in practitioners who care for traumatized populations: Secondary Traumatic Stress Scale, Compassion Fatigue Self Test for Helpers, and the Compassion Fatigue Scale—Revised. Conclusions Presence of secondary traumatic stress in nurses was reported in all of the studies included in this literature review. The use of small samples and a number of different instruments to measure secondary traumatic stress symptoms, however, hindered the ability to make comparisons across studies and to draw conclusions. None of the studies conducted to date have focused on secondary traumatic stress in psychiatric nurses. Suggestions for future research and clinical implications for what can be done to protect nurses from secondary traumatic stress are addressed.
Development of tolerance to ethanol in cultured adrenal chromaffin cells.

Dissociated bovine adrenal chromaffin cells in culture were utilized to study the mechanisms for development of cellular tolerance to ethanol. Three days after plating, cells were grown in either control medium or medium containing 200 mm ethanol for periods up to 6 days. Catecholamine release induced by carbachol, 80 mm K+, BAY K 8644, and veratrine was studied in ethanol-treated and untreated cultures. The presence of ethanol in vitro was inhibitory to all these stimuli in untreated cell cultures, carbachol-induced release being most sensitive (IC50 approximately 30 mm). After growth in ethanol for 6 days, carbachol-induced catecholamine release was completely resistant to the inhibitory effects of ethanol. The resistance to ethanol of carbachol-induced catecholamine release from cells grown in medium containing ethanol also extended to the inhibitory effects of butanol. The results show some similarities with changes observed in the central nervous system during the development of ethanol tolerance, and it is suggested that this model system may be useful in examining the mechanisms by which tolerance occurs.
Secured and reliable VM migration in personal cloud

The security and reliability issues that reside in VM live migration is a critical factor for its acceptance by IT industry. We propose to leverage Intel vPro and TPM to improve security in virtual machine live migration. A role-based mechanism with remote attestation is introduced, under which the VM migration is controlled by specific policies that are protected in seal storage. To provide high reliability in client virtualization, we also implement a checkpoint based method that only consumes 5% overall system resource according to the experimental result.
Helicoid Shiftamers for the Transport of π-Clumps and Charges

Hypothetical helical organic polymers with localized electrons, charges, and/or atoms are described, in which these localized substructures can move along the backbones of the polymers via sigmatropic H shifts.
Motion deblurring with graph Laplacian regularization

In this paper, we develop a regularization framework for image deblurring based on a new definition of the normalized graph Laplacian. We apply a fast scaling algorithm to the kernel similarity matrix to derive the symmetric, doubly stochastic filtering matrix from which the normalized Laplacian matrix is built. We use this new definition of the Laplacian to construct a cost function consisting of data fidelity and regularization terms to solve the ill-posed motion deblurring problem. The final estimate is obtained by minimizing the resulting cost function in an iterative manner. Furthermore, the spectral properties of the Laplacian matrix equip us with the required tools for spectral analysis of the proposed method. We verify the effectiveness of our iterative algorithm via synthetic and real examples.
Accurate radiation boundary conditions for the time‐dependent wave equation on unbounded domains

Asymptotic and exact local radiation boundary conditions (RBC) for the scalar time-dependent wave equation, rst derived by Hagstrom and Hariharan, are reformulated as an auxiliary Cauchy problem for each radial harmonic on a spherical boundary. The reformulation is based on the hierarchy of local boundary operators used by Bayliss and Turkel which satisfy truncations of an asymptotic expansion for each radial harmonic. The residuals of the local operators are determined from the solution of parallel systems of linear rstorder temporal equations. A decomposition into orthogonal transverse modes on the spherical boundary is used so that the residual functions may be computed e ciently and concurrently without altering the local character of the nite element equations. Since the auxiliary functions are based on residuals of an asymptotic expansion, the proposed method has the ability to vary separately the radial and transverse modal orders of the RBC. With the number of equations in the auxiliary Cauchy problem equal to the transverse mode number, this reformulation is exact. In this form, the equivalence with the closely related non-re ecting boundary condition of Grote and Keller is shown. If fewer equations are used, then the boundary conditions form highorder accurate asymptotic approximations to the exact condition, with corresponding reduction in work and memory. Numerical studies are performed to assess the accuracy and convergence properties of the exact and asymptotic versions of the RBC. The results demonstrate that the asymptotic formulation has dramatically improved accuracy for time domain simulations compared to standard boundary treatments and improved e ciency over the exact condition. Copyright ? 2000 John Wiley & Sons, Ltd.
Parent-in-Law Privacy Management: An Examination of the Links Among Relational Uncertainty, Topic Avoidance, In-Group Status, and In-Law Satisfaction

The present study used dual reasoning from communication privacy management theory and relational uncertainty to investigate how parents-in-law protected privacy boundaries within the parent- and child-in-law dyad. More specifically, the links among relational uncertainty, topic avoidance, family in-group status, and satisfaction were explored. Study 1 (N = 59) provided descriptive data on categories of parent-in-law relational uncertainty. These categories generated a measure of parent-in-law relational uncertainty employed in Study 2 (N = 104). Findings from Study 2 revealed intriguing interactions among family in-group status, relational uncertainty, and topic avoidance. In addition, relational uncertainty was negatively associated with family in-group status and parent-in-law satisfaction.
Accuracy of perinatal diagnosis of 45,X/46,XY mosaicism and electronic consultation of affected parents

Abstract Objective To assess parental satisfaction with e-mail consultations and fetal outcomes after consultation for offspring with 45,X/46,XY mosaicism. Patients and methods A chart review was performed of prenatal and postnatal e-mail consultations concerning 45,X/46,XY mosaicism at our institution. Prenatally, mosaicism was detected by amniocentesis; postnatally by phenotype and subsequent genotyping. Parents e-mailed us for a second opinion after internet searches. Follow-up parental satisfaction was evaluated by e-mail. Results E-mail consultation occurred in six prenatal and eight postnatal cases. One of the eight postnatal cases had a prenatal diagnosis but without our second opinion. In 7/8 postnatal cases, abnormal neonatal phenotype was evaluated by genotyping. Termination of pregnancy was a consideration in all six prenatal consultations, although not discussed by us. One fetus was stillborn. Postnatal karyotype was mosaic in 11/13 surviving neonates. Phenotypes in surviving fetuses were normal male (2/13), hypospadias and an undescended testis or streak gonad (9/13), female with mild clitoral hypertrophy (1/13), and normal female (1/13). The stillborn fetus was noted only to have a penis. Conclusion All parents reported in follow up that e-mail consultations provided them with enhanced clinical information, allowing them to make better informed clinical decisions.
Limitation of vesicular-arbuscular mycorrhizal activity in Leucaena leucocephala by Ca insufficiency in an acid Mn-rich oxisol

Glomus aggregatum and Leucaena leucocephala were interacted in an acid Mn-rich oxisol unamended or amended with lime [Ca(OH)2] or gypsum (CaSO4) at soil P concentrations considered optimal for mycorrhizal host growth and sufficient for mycorrhiza-free growth. At 0.02 mg P 1-1, both vesicular-arbuscular mycorrhizal fungal (VAMF) colonization and function were significantly curtailed if soil was not amended with gypsum or lime. The highest mycorrhizal effect was observed in the limed soil, followed by the soil treated with gypsum at the rate of 32 g Ca kg-1 soil. Higher concentrations of gypsum deleteriously affected VAMF infectivity and effectivity. The first increment of gypsum compensated completely for the VAMF colonization and for part of the mycorrhizal effect that was lost due to low pH. The superiority of the limed soil to that amended with gypsum apparently lies in the fact that Ca supply was assured in the former and also that the adverse effects of toxic constituents such as H+ and Mn2+ were eliminated. We were unable to separate the effect of Ca on VAMF from its effect on the host because a P concentration sufficient for mycorrhiza-free growth was not attained due to interaction of some of the P with Ca to form insoluble phosphate.
Establishment and characterization of bovine mammary epithelial cell lines.

One bovine mammary epithelial cell clone, designated PS-BME-C1, and two bovine mammary epithelial cell lines, designated PS-BME-L6 and PS-BME-L7, were derived from mammary tissue of a pregnant (270 day) Holstein cow. The cells exhibit the distinctive morphologic characteristics of mammary epithelial cells and express the milk fat globule membrane protein, PAS-III. They form domes when cultured on plastic substrata and acinilike aggregates when cultured on a collagen matrix. These cells are capable of synthesizing and secretingα-lactalbumin andα-s1-casein when cultured on a collagen matrix in the presence of insulin, cortisol, and prolactin. The cells have a near-normal diploid number and do not grow in suspension culture. When transplanted to the cleared mammary fat pads of female athymic nude mice, the cells readily proliferate forming noninvasive palpable spherical cellular masses within 8 wk after inoculation. The cells may become a useful tool to study the regulation of ruminant mammary epithelial cell growth and differentation.
Developing the Rivers of East and West Africa: An Environmental History. By Heather J. Hoag. (London, England: Bloomsbury Academic, 2013. Pp. xiv, 286. $34.95.)

The author of this study has written an engaging book that explores some historical aspects of several major African rivers. It is organized in six chapters, arranged in three sections, and framed ...
Airway Responses of Dogs with Ragweed and Ascaris Hypersensitivity

The occurrence and induction of immediate-type airway responsiveness to standardized ascaris antigen (SAA) was studied in dogs. Two of nine dogs with significant cutaneous reactivity to SAA had respiratory responses on initial aerosol challenge. Of the remaining seven dogs, six developed respiratory responses to SAA within three aerosol exposures. The respiratory responsiveness is of long duration, persisting at least four months, when the animals are exposed biweekly. Reaginic antibody against AA can be detected in the respiratory secretions of dogs sensitive to ascaris and, although this increases after antigen exposure, the increase in titer was not markedly different from the increase in serum titer. In contrast, no reaginic antibodies were detected in the RS of dogs allergic to ragweed, with respiratory responses. Respiratory function abnormalities in the canine respiratory response to ascaris were accompanied by changes in pulmonary resistance, which may precede other abnormalities during the development of respiratory responsiveness.
Zr@Si20: a strongly bound Si endohedral system

Abstract We present the results of local density approximation (LDA) calculations for a novel Si endohedral system, Zr@Si 20 . We compute an LDA endohedral binding energy for this system of 11.2 eV with respect to an isolated Zr atom and the most stable Si 20 isomer known. To understand the remarkable binding in this system, we compare the electronic structure of Zr@Si 20 with that of the corresponding bare cluster and with other Si 20 endohedral systems. We find that the bonding of all the endohedrals can be understood on the basis of a simple model previously used to explain endohedral bonding in small carbon fullerenes. Prospects for producing Zr@Si 20 experimentally are discussed.
Recovering from alcoholism in communal-living settings: Exploring the characteristics of African American men and women

African American men (n = 33) and women (n = 32) residing in a self-governed, communal-living aftercare program known as Oxford House were surveyed on socio-demographic, personality, recovery, and setting attribute variables. Women, compared to men, were more likely to report sexual abuse as an adult, be diagnosed with an eating disorder, engage in writing bad checks prior to recovery, and claim a stronger perception that Oxford House provided a structured and safe setting. Men, in contrast to women, were more likely to have engaged in drug sales and residential theft prior to recovery, claim less self-doubt about controlling their future life, and report greater attempts at rebuilding interpersonal relations and working 12-step programs. Men and women did not differ significantly in self-reports of co-dependency. Results indicate that gender specific and culturally sensitive characteristics upon both entry and in the course of recovery should be considered in communal facilities such as Oxford House.
Impacted Notch Bend Specimens

Abstract : The proposed method for testing and evaluating data generated by instrumented impact testings of notch bend specimens is evaluated by the experimental and numerical dynamic fracture results obtained in the past. As expected, brittle fracture of the photoelastic, steel and aluminum impacted notch specimens considered in this paper cannot be predicted by the static stress intensity factors at the instant of crack propagation. The fracture energy was only a fraction of the total absorbed energy and was equally unsuitable for dynamic fracture characterization of these specimens. This critical evaluation of the proposed method suggests that despite the enormous correlation studies which justify the use of static analysis, neither the proposed method nor the resultant static stress intensity factor should be used to evaluate the fracture data of impacted notch bend specimens of slightly different configurations. (Author)
Small non-fibrillar assemblies of amyloid β-protein bearing the Arctic mutation induce rapid neuritic degeneration

Recent studies suggest that soluble intermediates formed during amyloid beta-protein (Abeta) fibrillogenesis are neurotoxic. We studied early aggregation assemblies of wild-type and mutant Abeta bearing the E22G ("Arctic") familial Alzheimer's disease mutation. Using a novel method to present purified, disaggregated Abeta peptides to primary cortical neurons, the detailed temporal pattern of neurotoxicity was assessed. Neurons exposed to Arctic Abeta showed a progressive degeneration that was much more rapid than that with wild-type Abeta, beginning in dendrites and axons and leading to frank cell death. This neurotoxicity paralleled the aggregation process, with neuritic injury first appearing in the presence of small spherical Abeta oligomers, which were followed by a time-dependent elongation of curvilinear Abeta assemblies. One of the earliest neuritic changes was the formation of neurofilament-positive ringlets within axons, which disappeared as neurites followed by cell body degeneration. Our data support the hypothesis that small Abeta intermediates formed early in the aggregation process initiate cellular dysfunction beginning in neurites, leading to neuronal loss. A similar pattern of degeneration may occur during the preclinical and early clinical phases of Alzheimer's disease.
Use of functional near-infrared spectroscopy to monitor cortical plasticity induced by transcranial direct current stimulation

Electrical stimulation of the human cortex in conjunction with physical rehabilitation has been a valuable approach in facilitating the plasticity of the injured brain. One such method is transcranial direct current stimulation (tDCS) which is a non-invasive method to elicit neural stimulation by delivering current through electrodes placed on the scalp. In order to better understand the effects tDCS has on cortical plasticity, neuroimaging techniques have been used pre and post tDCS stimulation. Recently, neuroimaging methods have discovered changes in resting state cortical hemodynamics after the application of tDCS on human subjects. However, analysis of the cortical hemodynamic activity for a physical task during and post tDCS stimulation has not been studied to our knowledge. A viable and sensitive neuroimaging method to map changes in cortical hemodynamics during activation is functional near-infrared spectroscopy (fNIRS). In this study, the cortical activity during an event-related, left wrist curl task was mapped with fNIRS before, during, and after tDCS stimulation on eight healthy adults. Along with the fNIRS optodes, two electrodes were placed over the sensorimotor hand areas of both brain hemispheres to apply tDCS. Changes were found in both resting state cortical connectivity and cortical activation patterns that occurred during and after tDCS. Additionally, changes to surface electromyography (sEMG) measurements of the wrist flexor and extensor of both arms during the wrist curl movement, acquired concurrently with fNIRS, were analyzed and related to the transient cortical plastic changes induced by tDCS.
Polymers as conductors and semi-conductors

Mobile ions can be introduced thereby increasing the conductivity, with a limiting operating temperature range of 200°–250°C. Conductivity can be increased with the formation of conjugatd double bonds. Polymeric compounds may be synthesized with metallocyclic groups, where an atom of metal is bound to nitrogen atoms in a heterocyclic system in the basic chain of conjugation of the macromolecule. Here phtalocyanimes possess the greatest thermal stability. Lastly there are semiconducting polymers with conjugated double bonds containing hetero-atoms in the principle chain, having unpaired electrons of oxygen and nitrogen.
Idiopathic ischemic syndromes of the retina and optic nerve and their carotid origin

Abstract Most eye problems referred to vascular surgeons for workup of carotid disease are either transient (amaurosis fugax) or partial (retinal branch artery occlusion) visual loss. Patients with more severe total infarcts of the retina (central retinal artery occlusion) or of the head of the optic nerve ("ischemic optic neuropathy") are seldom suspected of carotid disease and, in the latter case, are generally labeled idiopathic. An explanation for the difference in attitude towards these conditions is suggested. A prescribed carotid etiology for these various ischemic syndromes of the eye and optic nerve was explored in a study of 20 consecutive patients who had acute ischemic eye/optic nerve problems. Special visualization of the neck, orbital, and retinal vasculature was obtained. Sixty percent had ipsilateral and 50% had contralateral carotid artery disease. The ophthalmic artery and the posterior ciliary arteries showed intrinsic lesions each in 25% of cases. Our pilot study concludes that there is strong evidence that most of these ischemic eye syndromes are related to carotid artery disease, which is found in the majority of patients. In a minority of them ischemic problems may be due to arteritis or to intrinsic disease of the ophthalmic artery. A more cohesive approach to the study and treatment of these different entities is supported by the suggestion of a common etiology for most of them. Close collaboration with ophthalmologists will be needed to improve the present management of these eye conditions. (J VASC SURG 1985;2:649-53.)
Active Stabilization of Surge in an Axicentrifugal Turboshaft Engine

Active stabilization of surge was implemented on an Allied Signal LTS-101 axicentrifugal gas producer, reducing the surging mass flow by I percent, for an operating range increase of II percent. Control was achieved using high-response sensors in the inlet and diffuser throat, coupled to actuators that injected air near the diffuser throat. System identification and modeling indicate that a classical surge-type eigenmode and an eigenmode associated with engine duct acoustics dominate the engine's input-output properties. The surge eigenmode's stability determines the open-loop surge mass flow. A robust linear controller with three inputs and one output stabilized this eigenmode without destabilizing the acoustic mode. The controller facilitated a 1 percent reduction in surging mass flow at 95 percent N1 corrected; this increases the engine's choke to surge stable operating range by 11 percent. This paper elucidates the measured unsteady presurge behavior of the engine, and outlines a systematic procedure for surge control law development.
Seismic response of a cylindrical shell embedded in a layered viscoelastic half-space; I, Formulation

A method to obtain the three-dimensional harmonic response of a infinitely long cylindrical shell of circular cross-section embedded in a layered viscoelastic half-space and subjected to harmonic plane waves impinging at an oblique angle with respect to the axis of the shell is presented. The procedure combines an indirect integral representation for the field in the exterior half-space with a model of the pipeline or tunnel based on Donnell shell theory. The integral representation for the soil is based on the use of moving Green's functions for the layered viscoelastic half-space. The accuracy of the formulation is tested by comparison of results obtained by using different discretizations. Extensive comparisons with previous two- and three-dimensional results for the case of a shell embedded in a uniform half-space and some new numerical results for a shell embedded in a multilayered half-space are presented in a companion paper.
Postnatal development of the mandible of the cat.

Summary The growth of the mandible was studied by a histologie analysis of frontal and horizontal sections through the mandibles of sixteen kittens varying in postnatal age from 1 to 90 days. Meekel's cartilage, which appeared as an inactive polyspheroid bar at the posterior and inferior third of the mandibular symphysis, completely disappeared by the fourteenth postnatal day and did not contribute to the development of the mandible in this area. A growth center at which the endochondral type of bone formation occurred was present in the symphysis of a 1-day-old kitten and continued to be active until the sixtieth day, at which time eruption of the deciduous canines into the oral cavity was complete. Upon cessation of the growth of this cartilage, it persisted at the midline in the adult cat as fibrocartilage. Calcified cartilage was observed in the primary trabeculae as far laterally as the deciduous first molar, which indicated that the development of the alveolus in this region may have been due to the growth of the symphyseal cartilage. A system of anastomosing veins, for which the term venous lakes has been suggested, occurred at the midline, separating the two heads of cartilage from one another, and also surrounded the remnants of Meckel's cartilage. It has been postulated that the purpose of these venous lakes may have been to separate the two halves of the mandible, allowing the development of this anterior growth center. The increase of intercanine width for the deciduous canine in cats was brought about by the development of an endochondral type of bone formation at the mandibular symphysis. The cartilage in the mandibular symphysis not only served as a center of growth but, by its directional growth, determined the shape and form of the anterior portion of the mandible.
Analysis of Laser Measurement of High-Altitude Aircraft Emissions

Accurate prediction of the environmental impact of stratospheric aircraft operation requires highly sensitive and specific measurement of effluents which have long residence times and possible catalytic interactions with the ambient atmosphere. Calculations have been performed to analyze three narrow bandwidth tunable laser measurement techniques for high altitudes where molecular absorption lines are narrow. Two ended absorption measurements using state-of-the-art tunable infrared diode lasers can provide sensitivities of ^ 0.02-0.2 ppm over 10 m for O3, CO, NO, H2O, and SO2 with minimal interference effects. Heterodyne radiometry of radiation from a hot near wake is capable of measuring initial wake concentrations, while heterodyne radiometry of absorption of solar radiation is sensitive to < 0.01 ppm of NO and CO in the far wake. These heterodyne measurements, with tunable diode laser local oscillators, will require development of milliwatt per mode diode lasers. Remote (1 km) resonance fluorescence measurements using dye lasers are capable of measuring to 0.15 ppm NO2. Sensitivities can be improved to close to ambient levels during wake penetration.
Acute administration of alcohol blocks cocaine-induced striatal c-fos immunoreactivity protein in the rat.

Immediate-early genes, such as c-fos, are induced in the brain by cocaine and other psychotropic drugs. This induction is thought to be mediated via the activation of dopamine D1 and glutamate N-methyl-D-aspartate (NMDA) receptor subtypes. Because alcohol selectively blocks NMDA receptor function, we determined the ability of alcohol to block the expression of c-fos normally induced by systemic cocaine exposure in perikarya of the rat striatum. Acute administration of alcohol (2 g/kg; IP) approximately 30 min prior to a single cocaine (20 mg/kg) injection significantly reduced the patchy appearance of intensely immunoreactive gene signal in dorsal-central quadrants of the caudate putamen. Separate administration of three doses of alcohol alone (1, 2, or 3 g/kg) was ineffectual in inducing FOS-like protein in this or other regions of the rat brain. The blockade of the encoded protein by alcohol was partial in magnitude reminiscent of that produced by MK-801 and related NMDA receptor antagonist drugs. Furthermore, the blockade of cocaine-induced FOS-like protein by alcohol occurred at a dose which produced a blood alcohol concentration of approximately 180 mg/dl (40 mM), comparable to that detected in intoxicating humans. Considering the fact that the concomitant use of alcohol and cocaine is the most common substance abuse pattern found in the addictive population, the present results suggest an antagonistic effect exerted by these two drugs at the transcriptional level and further support the consensus that NMDA receptors are the plausible surface-target elements mediating some of the effects of alcohol and cocaine. © 1994 Wiley-Liss, Inc.
Involvement of Local Lamellipodia in Endothelial Barrier Function

Recently we observed that endothelial cells cultured in tightly confluent monolayers display frequent local lamellipodia, and that thrombin, an agent that increases endothelial permeability, reduces lamellipodia protrusions. This led us to test the hypothesis that local lamellipodia contribute to endothelial barrier function. Movements of subcellular structures containing GFP-actin or VE-cadherin-GFP expressed in endothelial cells were recorded using time-lapse microscopy. Transendothelial electrical resistance (TER) served as an index of endothelial barrier function. Changes in both lamellipodia dynamics and TER were assessed during baseline and after cells were treated with either the barrier-disrupting agent thrombin, or the barrier-stabilizing agent sphingosine-1-phosphate (S1P). The myosin II inhibitor blebbistatin was used to selectively block lamellipodia formation, and was used to test their role in the barrier function of endothelial cell monolayers and isolated, perfused rat mesenteric venules. Myosin light chain (MLC) phosphorylation was assessed by immunofluorescence microscopy. Rac1 and RhoA activation were evaluated using G-LISA assays. The role of Rac1 was tested with the specific inhibitor NSC23766 or by expressing wild-type or dominant negative GFP-Rac1. The results show that thrombin rapidly decreased both TER and the lamellipodia protrusion frequency. S1P rapidly increased TER in association with increased protrusion frequency. Blebbistatin nearly abolished local lamellipodia protrusions while cortical actin fibers and stress fibers remained intact. Blebbistatin also significantly decreased TER of cultured endothelial cells and increased permeability of isolated rat mesenteric venules. Both thrombin and S1P increased MLC phosphorylation and activation of RhoA. However, thrombin and S1P had differential impacts on Rac1, correlating with the changes in TER and lamellipodia protrusion frequency. Overexpression of Rac1 elevated, while NSC23766 and dominant negative Rac1 reduced barrier function and lamellipodia activity. Combined, these data suggest that local lamellipodia, driven by myosin II and Rac1, are important for dynamic changes in endothelial barrier integrity.
Secrecy and disclosure as rhetorical forms

Attitudes toward secrecy and disclosure are expressed as rhetorical forms, especially in the archetypal role of translator and in commonplaces.
Back to the metal age: battle for metals at the host–pathogen interface during urinary tract infection

Urinary tract infection (UTI) represents one of the most common bacterial infections in humans and uropathogenic E. coli (UPEC) is the major causative agent of UTI in people. Research on UPEC and other bacterial pathogens causing UTI has now identified the critical role of metal transport systems in the pathogenesis of UTI. Here we review the major effectors of metal transport in bacteria and host proteins that impair metal acquisition by bacterial pathogens. In particular, we describe the studies that identified iron, zinc and nickel import and copper export as key virulence and fitness determinants during UTI. Various metal transport systems and mechanisms that govern the expression of metal transport systems are also presented here. Specific examples from UPEC and other uropathogens, when available, are presented to depict the battle for metals at the host–pathogen interface during UTI.
The transition to nondepletable energy

As depletable energy becomes increasingly scarce and expensive, energy markets will turn to a multitude of nondepletable sources of energy. The rate at which this transition occurs will depend on the quantities of fuels available, production costs, government policies, and the choices of major producers. In this paper, we analyze the transition to nondepletable fuels, first in the context of a social planning model, then using a Stackelberg model to represent the dynamic game between owners of depletable and nondepletable fuels. We show that the pace of capacity expansion in the nondepletable sector has a strong influence on socially optimal energy prices and production rates. With the Stackelberg model, we characterize the strategy a market-dominating producer of depletable energy will use against the nondepletable sector. Numerical implementations of this model allow us to compare the socially optimal and market-determined outcomes. Our results show how a dominant depletable-energy producer can manipulate the nondepletable sector by pricing at the marginal cost of backstop output during an early phase of resource depletion.
An empirical study of autonomous work groups relationships between worker reactions and effectiveness

This paper reports on findings from an empirical study of thirty autonomous work groups, It deals with systems at the group level, particularly their producer and decider subsystems. Each work group operated within the same organization, making the same kind of product using the identical process. This study attempts to explain the differences between high productive and low productive autonomous work groups. The focus is on two key areas of worker perceptions: satisfaction with the job and perceptions of work group leadership. Results show the importance of establishing and communicating a policy of promotional opportunities to reward high performance. Leadership dimensions (superior orientation and consideration) that discriminate between high and low production groups are identified. These findings have implications in the selection and training of team leaders and the management of autonomous work groups.
Population of high-spin states in the actinide region by heavy-ion transfer reactions

Abstract Population of states with spin as high as 24+ (26+) in 234U is observed in the one-neutron pickup reaction 235U(58Ni, 59Ni)234U at Elab = 325 MeV. The total γ-ray energy and multiplicity measured in this reaction channel indicate that transfer is populating mostly “cold” states, without appreciable fission competition. The prospect of studying high-spin states in the actinide region using even heavier projectiles is discussed, and we conclude that discrete states with spin higher than 30 may be accessible by these methods.
Angiotensin II regulates growth of the developing papillas ex vivo.

We tested the hypothesis that lack of angiotensin (ANG) II production in angiotensinogen (AGT)-deficient mice or pharmacologic antagonism of ANG II AT1 receptor (AT1R) impairs growth of the develop...
Longitudinal succession in impact assessment of river system fish communities

Longitudinal succession indicates that diversity and species richness of fish communities increase with increasing river size (increasing habitat complexity and environmental stability). Cultural impacts tend to decrease diversity, species richness, and evenness. To assess the impacts of cultural events on the fish community of a river system, the bias caused by longitudinal succession was removed by normalizing diversity indices and species richness values for river size. The relationships between an impact index and the community parameters of evenness, normalized diversity, and normalized species richness were determined by regression analysis. Similar relationships were determined using nonnormalized data, and the results compared. The two sets of regressions were similar in terms of variance explained.Evenness, which is unaffected by longitudinal succession, appears to be the most impact sensitive parameter. A major source of error and confusion results from introduced species which are simultaneously sources of biological impact and a component of the community. Numbers of introduced species tend to increase with both impact and river size.
Assessment of the Acute and Chronic Health Hazards of Hydraulic Fracturing Fluids

There is growing concern about how hydraulic fracturing affects public health because this activity involves handling large volumes of fluids that contain toxic and carcinogenic constituents, which are injected under high pressure through wells into the subsurface to release oil and gas from tight shale formations. The constituents of hydraulic fracturing fluids (HFFs) present occupational health risks because workers may be directly exposed to them, and general public health risks because of potential air and water contamination. Hazard identification, which focuses on the types of toxicity that substances may cause, is an important step in the complex health risk assessment of hydraulic fracturing. This article presents a practical and adaptable tool for the hazard identification of HFF constituents, and its use in the analysis of HFF constituents reported to be used in 2,850 wells in North Dakota between December 2009 and November 2013. Of the 569 reported constituents, 347 could be identified by a Che...
In Defense of the Dead: Antígona furiosa, by Griselda Gambaro

This study establishes parallels between the biological fratricide in Sophocles’ Antigone and the metaphorical fratricide in Griselda Gambaro's Antigona furiosa (Buenos Aires, 1986). The article examines how in both plays Antigone seeks to defend her dead brother in her quest for closure. The biological fratricide over power in Thebes, which left both Eteocles and Polynices dead, and the metaphorical fratricide carried out in Argentina between the followers of Peron and those who opposed his ideology are strikingly similar. The assassinations of numerous Argentine citizens and the disappearance of others resulted in parallel actions to defend the dead and seek closure. Gambaro, this study argues, saw clearly what was happening in her country and used the repressive military regime that came into power in 1976 as a metaphor for the right-wing faction of society—a metaphor for Eteocles who refused to relinquish his rule after one year. Gambaro used the disappeared as a metaphor for Polynices—the unburied wh...