cssi/SciSciGPT-SciSciNet huggingface dataset:
Stem Cell-Based Therapies: Promises, Obstacles, Discordance, and the Agora

Stem cell research has entered the public consciousness through the media. Proponents and opponents of all such research, or of human embryonic stem cell research specifically, engage in heated exchanges in the modern public forum where stakeholders negotiate, the agora. One common claim that emerges from the fray is that a particular type of stem cell research should be pursued as the most promising path toward the reduction of suffering and untimely death for all of humanity. Upon evaluation, experimental data regarding the potential role of stem cells in regenerative therapies for three conditions-spinal cord injury, type 1 diabetes, and cardiovascular disease-tell distinct, complex, and inconclusive stories. Further analyses in this article incorporate realistic considerations of a broad range of relevant factors: limited funding for biomedical research, media motives, the discordance hypothesis of evolutionary medicine, the relationship between religion and science, medical care in developing nations, and culture wars over abortion. Holistic investigation inspired by the current agora conversation supports the need to drastically change interactions regarding stem cell research so that its potential to benefit humanity may be more fully realized.
Documenting Religious Activity in Nonreligious Repositories

In 1981, when I was a reference librarian at the University of Florida, the lack of adequate African‐American primary resources provoked me to initiate the National African‐American Pentecostal Project. Subsequently, I have collected a vast store of records, including obituaries, photographs, scrapbooks, souvenir booklets, books, and newspaper clippings. While collecting this material, I learned four things: First, private individuals possess scores of records pertaining to the lives and experiences of black Pentecostals. Second, many black and white Pentecostals are willing and eager to contribute their records if they are approached diplomatically. Third, many black Pentecostals, especially older members, have a strong sense of history and feel the pain of having been omitted from historical scholarship. And fourth, since I have returned some of these records to their owners, there is a need to permanently preserve the records of black Pentecostals.
Experimental Validation of Middleware-based QoS Control in 802.11 Wireless Networks

Due to the shared medium nature of wireless networks, the uncertainties caused by collisions and interferences make the quality of service (QoS) issue harder than its wired counterpart. Many publications have been focused on network and MAC layer design to address the QoS issue in wireless networks. However, the middleware design has been overlooked. For QoS support, we need to map the QoS requirement of applications to performance metrics. Middleware is the place we do such mapping. In this paper, we use packet level priority to bridge the QoS requirements and performance. Through middleware priority adaptation, we aim to make the premium traffic meet the QoS requirement, we study the impact of middleware priority adaptation on QoS performance, including bandwidth and end- to-end delay, via experiments with multimedia flows over IEEE 802.11 environment. Our evaluation is based on experiments in both WLAN and ad hoc network environment. Our investigation shows that middleware adaptation is efficient in assisting to achieve QoS in many scenarios.
High Performance reversed phase chromatography of Natural triglyceride mixtures: Critical pair separation

The separation of the critical triglyceride pairs C48:0, C50:l, C54:3ccc and C54:3ttt as well as C54:2, C52:l and C50:l has been accomplished without the aid of any interacting ion such as silver. A theoretical carbon number (TCN) for the unsaturated triglycer-ides can be calculated from the carbon number (CN) and capacity factor (k’) relationship of the saturated triglycerides, and used to predict the separation of critical pairs. A mathematical equation was derived for the identification of not only the triglycerides by their carbon number and number of double bonds but also the possible acyl groups present in these triglycerides. The pattern of triglyceride elution sequence within each triglyceride category with the same equivalent carbon number (ECN) starts with the triglyceride with the highest number of double bonds and terminates with those with the lowest number of double bonds, with the lower ECN triglycer-ides eluting ahead of those with higher ECN. A possible mechanism for the separation of these triglycerides on highly efficient columns packed with 5n silica bonded with the octadecyl stationary phase is postulated.
A Latent Class Analysis of Maternal Responsiveness and Autonomy-Granting in Early Adolescence: Prediction to Later Adolescent Sexual Risk-Taking

The present study sought to extend empirical inquiry related to the role of parenting on adolescent sexual risk-taking by using latent class analysis (LCA) to identify patterns of adolescent-reported mother responsiveness and autonomy-granting in early adolescence and examine associations with sexual risk-taking in mid- and late-adolescence. Utilizing a sample of 12- to 14-year-old adolescents (N = 4,743) from the 1997 National Longitudinal Survey of Youth (NLSY97), results identified a four-class model of maternal responsiveness and autonomy-granting: low responsiveness/high autonomy-granting, moderate responsiveness/moderate autonomy-granting, high responsiveness/low autonomy-granting, high responsiveness/moderate autonomy-granting. Membership in the low responsiveness/high autonomy-granting class predicted greater sexual risk-taking in mid- and late-adolescence compared to all other classes, and membership in the high responsiveness/ moderate autonomy-granting class predicted lower sexual risk-taking. Gender and ethnic differences in responsiveness and autonomy-granting class membership were also found, potentially informing gender and ethnic disparities of adolescent sexual risk-taking.
Somatosensory evoked response: application in neurology

One technique used for short-latency somatosensory evoked response (SER) is described. SER following nerve stimulation is a unique non-invasive, clinical test used to evaluate the somatosensory pathways. It tests the physiological function of the median nerve, the brachial plexus, the C6-7 cervical roots, cervical spinal cord, the cuneate nuclei, the medial lemniscus, the thalamus, and the contralateral sensory cortex. It has been shown to be a reliable and useful clinical test partiicularly in multiple sclerosis and comatose patients. The promising technique of SER following peroneal nerve stimulation is mentioned.
Segregation roasting of nickel, copper and cobalt from deep-sea manganese nodules

Abstract The recovery of nickel, copper and cobalt from ocean manganese nodules by a segregation roasting technique was investigated under a wide range of conditions with several nodule samples all of which gave similar results. The best conditions for the segregation of the metals were achieved with CaCl 2 as the chloride source at a batch retention time of approximately two hours; the highest recoveries were obtained at approximately 850°C for copper and at 1,050°C for nickel and cobalt. At 850°C, copper recovery was 75%, but nickel and cobalt recoveries were only about 25%. At 1,050°C, the nickel and cobalt recoveries were increased to about 60%, but the copper recovery dropped to only 35%. Electron-probe microanalysis showed the segregated metal to be an alloy, indicating that gaseous reactions play an important role in the reduction of chlorides to metal during the process.
Improved fusion of visual measurements through explicit modeling of outliers

With the recent proliferation of low-cost, light-weight, and high-resolution cameras, significant research has been conducted on utilizing visual sensors within navigation systems. Visual sensors, however, are different from more traditional sensors utilized within estimation systems because cameras do not directly sense the quantity (or its derivative/integral) to be estimated/fused. Instead, the luminance outputs of the camera sensor are processed algorithmically to obtain some other quantity that is used as an input to an estimator. Sample outputs of vision processing algorithms utilized in automated systems include optical flow, feature tracks, or object localization. Unfortunately, the outputs of these algorithms do not conform to the traditional model of the true measurement plus a Gaussian random process. Instead, each of the algorithms occasionally produce spurious outputs (outliers) that deviate significantly from the true value being observed. In addition, the probability of an outlier occurring and its effects on down-stream algorithms are generally unknown. In this paper, we present an estimation approach that explicitly considers the probability of outliers and performs maximum likelihood estimation over a distribution with outliers. In addition to more accurately estimating the final state, the predicted uncertainty of the system is shown to be accurate.
Surface Separation and Contact Resistance Considering Elasto-Plastic Multi-Scale Rough Surface Contact

The current work considers the multiscale nature of surface roughness in a new model that predicts the real area of contact and surface separation, all as a function of load. By summing the distance between the two surfaces at all scales, a model of surface separation as a function of dimensionless load is also obtained. The model is also able to make predictions for thermal (and electrical) contact resistance. In striving for a more realistic model, the multi-scale model accounts for the effects of a rough surface geometry ranging from macro down to the nano scale. A previous rough surface contact model was based on stacked elasto-plastic spheres. This work uses stacked 3-D sinusoids to represent the asperities in contact at each scale of the surface. The results are also compared to several other existing rough surface contact models and experimental results.© 2007 ASME
Consciousness beyond the comparator

Gray's comparator model fails to provide an adequate explanation of consciousness for two reasons. First, it is based on a narrow definition of consciousness that excludes basic phenomenology and active functions of consciousness. Second, match/mismatch decisions can be made without producing an experience of consciousness. The model thus violates the sufficiency criterion.
Do We Need a National Incident Reporting System for Medical Imaging

The essential role of an incident reporting system as a tool to improve safety and reliability has been described in high-risk industries such as aviation and nuclear power, with anesthesia being the first medical specialty to successfully integrate incident reporting into a comprehensive quality improvement strategy. Establishing an incident reporting system for medical imaging that effectively captures system errors and drives improvement in the delivery of imaging services is a key component of developing and evaluating national quality improvement initiatives in radiology. Such a national incident reporting system would be most effective if implemented as one piece of a comprehensive quality improvement strategy designed to enhance knowledge about safety, identify and learn from errors, raise standards and expectations for improvement, and create safer systems through implementation of safe practices. The potential benefits of a national incident reporting system for medical imaging include reduced morbidity and mortality, improved patient and referring physician satisfaction, reduced health care expenses and medical liability costs, and improved radiologist satisfaction. The purposes of this article are to highlight the positive impact of external reporting systems, discuss how similar advancements in quality and safety can be achieved with an incident reporting system for medical imaging in the United States, and describe current efforts within the imaging community toward achieving this goal.
Fecal corticoid metabolite measurement in the cheetah (Acinonyx jubatus)

This longitudinal study addresses the relationship of cortisol excretion to ovarian activity in captive female cheetahs. A radioimmunoassay was developed and validated to measure corticoid metabolite concentrations in feces. A restraint experiment was used to demonstrate that fecal cortisol is detectable following stressful episodes. In studies of 7 females, fecal cortisol output indicated that they could be placed into 3 different categories. Females of the high-in-cortisol category (∼200 ng/g feces, n = 2) were independently rated by caretakers as the most nervous individuals in the collection (n = 24). These females appeared to be compromised in their ovarian cycling, as indicated by fecal estrogen measurements. In contrast, reproducing females fell into the low and intermediate cortisol excretion categories. A non-cycling high-cortisol female had an episodic cycle following a period of relatively low (intermediate) cortisol levels, followed by resumption of acyclicity and high cortisol excretion. Stress and reproductive failure may, therefore, be associated in the female cheetah. The close proximity of conspecifics as a potential source of stress and, consequently, suppressed ovarian activity in some females is suggested by these results. Zoo Biol 16:133–147. 1997 © 1997 Wiley-Liss, Inc.
Direct measurement of the lowest excited singlet state lifetime of all-trans-β-carotene and related carotenoids

Abstract A 4 ps, 510 nm laser pulse was used to electronically excite toluene solutions of all-trans-β-carotene, canthaxanthin, and β-8'-apocarotenal. The 430–510 nm electronic absorption band of each carotene bleaches immediately upon excitation and recovers with single-exponential kinetics: τ = 8.4 ± 0.6 ps for all-trans-β-carotene, 5.2 ± 0.6 ps for canthaxanthin, and 25.4 ± 0.2 ps for β-8 ' -apocarotenal. The results are discussed in terms of the excited singlet state properties of carotenoids.
The American planning tradition : culture and policy

The past half-century's radical transformation of American cities and regions has paradoxically stimulated our interest in older forms of cities and renewed our respect for the planning tradition that created them. Today, with everything urban and public perpetually in crisis, we turn attentively toward the figures who shaped our cities and left a magnificent legacy of public spaces, public transit, public parks, public libraries, public schools, public health, and public safety. The American Planning Tradition reevaluates those planners and their times in a series of essays by some of today's preeminent urbanists. These contributors view such antecedents as Albert Gallatin, Frederick Law Olmsted, Daniel Burnham, Edward Bennett, and Lewis Mumford not merely as precursors who prepared the way for the revelations of modern planning theory, but as contemporaries and even prophets who struggled with many of the same problems that afflict us, and responded with more vision, confidence, and hope than we seem to have today. Their chapters discuss principles proposed for American urban planning, cover a series of national efforts at planning for transportation, resources, and the environment, and describe recent experiences in New Orleans, Portland, Chicago, and Boston. The contributors are Robert Fishman, John Thomas, Michael J. Lacey, James Westcoat, Jr., Alan Brinkley, Margaret Weir, Arnold R. Hirsch, Carl Abbott, Judith A. Martin and Sam Bass Warner, Jr, and Anne Whiston Spirn.
Nonlinear thermo-optic model for the characterization of optical self-heating in electro-optic semiconductors

A nonlinear thermo-optic model for the characterization of electro-optic semiconductor probes used to simultaneously measure electric field and temperature is presented. Optical thermal self-heating of the semiconductor is shown to be the primary limiting mechanism for temperature dynamic range, electro-optic modulation power, temperature sensitivity, temperature contrast, and temperature invasiveness. Tradeoff considerations of these parameters as a function of optical wavelength and input optical power are discussed. Optical temporal defocusing is shown to minimize the effects of nonlinear absorption. Simulation results are compared with measurements.
Coping with the double bind: Bidirectional learning and development in the zone of proximal development

Abstract This article examines the interaction between a tutor and her student as they discuss an essay question from the student's sociology class. Drawing on the theories of Vygotsky and Bakhtin, I explore (a) the conflicts that arose for both tutor and tutee as they grappled with the competing discourses that informed their respective understandings of the essay question and (b) the shifts in tool use that were a result of attempting to cope with these tensions. Through my analysis, I demonstrate that both tutor and tutee showed evidence of learning, but only the tutor exhibited signs of development. I argue that this interaction is an example of the bidirectional nature of Vygotsky's zone of proximal development and provides insight into the nature of learning and development for the “expert” as well as the “novice” in this space.
Endovascular management of a basilar artery false aneurysm secondary to endoscopic third ventriculostomy: case report.

OBJECTIVE AND IMPORTANCE: Third ventriculostomy for the management of noncommunicating hydrocephalus is a commonly performed procedure with a 5% complication rate. One of the known complications is basilar artery injury. CLINICAL PRESENTATION: We report a case of basilar artery injury, intraventricular hemorrhage, and false aneurysm formation in a 30-month-old boy after third ventricle floor fenestration. INTERVENTION: The false aneurysm was managed with endovascular trapping by use of Guglielmi detachable coils without morbidity. CONCLUSION: Endovascular therapy can be used successfully to manage vascular injury after third ventriculostomy.
Gravity in 2 + 1 dimensions coupled to point-like sources: a flat Chern-Simons gauge theory equivalent to Einstein's☆

Abstract We present a classical Chern-Simons gauge theory for planar gravity coupled to point-like sources. The theory is defined in terms of flat coordinates whose relation with the space-time coordinates can be unambiguously established. Though flat, the theory is equivalent to Einstein's as can be shown in some explicit and non-trivial examples. The procedure we have developed allows us to find the space-time metric, the geodesics equations and also provides the coordinates that flatten the space-time manifold. In particular, we recover the stationary metric generated by N spinning particles and we discuss in full detail the matching conditions satisfied by the space-time coordinates that flatten the metric in the two-particle case.
The Stigma Receptivity Scale and its association with mental health service use among bereaved older adults

The purpose of this article was to determine whether the Stigma Receptivity Scale (SRS) predicts use of mental health services among community-dwelling bereaved older adults. We analyzed interviews of 135 people in Connecticut to evaluate whether three subscales and 12 SRS items were associated with access to any mental health service in the past 60 days using logistic regression analysis. Two SRS items predicted recent use of mental health services among bereaved individuals with and without complicated grief: receptivity to a bereavement support group (adjusted OR = 5.14; 95% CI, 1.11, 23.85) and individuals who were not concerned about meeting criteria for a mental illness (adjusted OR = 0.07; 95% CI, 0.01, 0.58). The SRS significantly predicted recent access to mental health treatment among bereaved elderly people. This type of measure could be used to determine those most likely in need of education and support to increase their likelihood of accessing mental health services.
Regional blood-brain barrier transport of glucose after portacaval anastomosis.

The regional influx of glucose across the blood-brain barrier was measured in rats 5 to 6 weeks after a portacaval anastomosis or sham operation. D-[14C]Glucose was infused intravenously for 15sec while arterial blood was sampled continuously for measurement of plasma radioactivity and glucose concentration. Brain tissue radioactivity was measured by quantitative autoradiography. Glucose influx and plasma clearance (permeability times surface area;PS) were calculated from the net disintegrations per minute per gram in brain, the plasma radioactivity integral, and the plasma glucose concentration. In shunted rats influx was decreased by about 22% (in the brain as a whole) compared to that in controls. This decrease was almost entirely due to the decrease in plasma glucose concentrations (27%). ThePS, normalized to take plasma concentrations into account, showed a slight decrease in most of the brain except the telencephalon. For the brain as a whole this decrease amounted to 11%. The regionalPS and glucose utilization are known to be coupled and the relationship between these was the same in sham-operated and shunted rats. The decrease inPS observed in shunted rats was commensurate with their lower rates of glucose use; thus, the transport process of glucose from plasma to brain appeared to be unaffected by portacaval shunting.
An integrated confocal and magnetic resonance microscope for cellular research.

Complementary data acquired with different microscopy techniques provide a basis for establishing a more comprehensive understanding of health and disease at a cellular level, particularly when data acquired with different methodologies can be correlated in both time and space. In this Communication, a brief description of a novel instrument capable of simultaneously performing confocal optical and magnetic resonance microscopy is presented, and the first combined images of live Xenopus laevis oocytes are shown. Also, the potential benefits of combined microscopy are discussed, and it is shown that the a priori knowledge of the high-resolution optical images can be used to enhance the boundary resolution and contrast of the MR images.
Symmetric Minimal Covering Problem and Minimal PLA's with Symmetric Variables

This paper first discusses the symmetric property of the minimal covering problem in terms of group theory and then the use of this property in the branch-and-bound method for solving the problem. Computational results on solving sample problems are shown to demonstrate the improvement of computational efficiency of the branch-and-bound method by the utilization of the symmetric property. The sample problems contain the minimal sum derivation of symmetric switching functions, as an application to the design of minimal programmable logic arrays (PLA's). It is shown that when the minimal covering problem derived for the given switching function has symmetric permutations, the given switching function may not be symmetric; although when the given switching function is symmetric, the minimum covering problem obtained from the function is symmetric. The branch-and-bound method based on the symmetric property can be applied not only to symmetric switching functions but also to switching functions which are not symmetric, if the corresponding minimal covering problems have symmetric permutations. The method can be also applied to minimal covering problems which arise outside the minimal sum derivation problems for switching functions.
The common life of yards

Recent scholarship has begun to reimagine the commons beyond its traditional meaning as a collectively owned and managed natural resource. Building on research that considers commons through the practices which produce and maintain them—commoning—this article analyzes how privately owned front and backyards participate in urban commons. Through ethnographic research in three neighborhoods of Minneapolis, Minnesota, the article shows how these commons are made in two key registers: through yards as shared territories and through everyday practices of sharing plants across individual yards. The article’s central claim is that yards and the everyday practices which take place in and through them constitute one nodal point in the making of urban commons. In so doing, logics of private property come to be interwoven with logics of commoning. By finding a diverse range of common lives of yards, this article adds to emerging conversations about the nature of urban commons.
Rhabdom degradation in white-eyed and wild-type crayfish after long term dark adaptation

Rhabdom degradation has been compared in groups of wild-type (WT) and white-eyed mutant (WEM) crayfish exposed to a 12∶12 LD cycle after 1 month of continuous darkness. Light and electron microscopic quantitative analysis of the lysosome-related bodies (LRB) formed during rhabdom degradation show that WEM photore-ceptors produced few LRB during the first 12 h of light exposure, but the microvilli in the rhabdom became severely disrupted. An increase in LRB production began in the WEM after the initial light-dark transition, and continued during the first dark period, as well as throughout the second light cycle. Analysis of fluctuations in specific LRB types shows that multivesicular bodies (MVB) were the major contributor to the total organelle population seen in the WEM, and lamellar bodies (LB) showed a significant drop following light onset of the second light cycle. Wild-type crayfish maintained in long-term dark before exposure to cyclic lighting showed a characteristic increase in LRB production in the light and a decline in the dark. However, LRB persisted throughout the light period and did not show a characteristic decline during the second 6 h in the light. This exaggerated degradative response in the WT animals was repeated during the second light cycle.
Shifting the Prism: Case Explications of Institutional Analysis in Nonprofit Organizations

Teachers of nonprofit organization studies, nonprofit practitioners, and consultants are increasingly dissatisfied with the standard management model approach to solving organizational problems in nonprofits. The standard model provides rational "fixes" to complex organizational issues that miss the contextual, dynamic, and varied environments in which nonprofits operate. This article proposes that an institutional analysis approach represents an important alternative to the standard model because it views nonprofit organizations as embedded in and subcomponents of larger communal and organizational systems. The article explores five elements that distinguish the institutional analysis approach from the standard model: (1) the organization should be considered to exist in social systems, (2) cultural influences that shape organizational behavior must be sought out and analyzed, (3) a variety of constituencies are likely to be important and powerful, (4) coercive influences often shape nonprofits, and (5) ...
Polycystic Ovarian Syndrome Management Options

Polycystic ovarian syndrome (PCOS) is a disorder of androgen excess and ovarian dysfunction. Hirsutism and elevated free testosterone levels are the most consistent signs of the androgen excess. Irregular, infrequent, or absent menses and infertility are symptoms of ovulatory dysfunction. Obesity is also a feature of this syndrome and contributes to associated metabolic abnormalities. Lifestyle modification should be the first treatment and is effective in reducing the signs and symptoms. The ovulatory infertility associated with PCOS can be overcome in most cases with oral (clomiphene citrate or letrozole) or injectable (gonadotropins) agents. Surgical intervention is reserved for cases resistant to medical management.
The resolvent of the linear problem of the inverse method

Abstract The N -dimensional resolvent of the linear problem of the inverse scattering method is introduced. For N = 1 the definition reduces to the well known resolvent of an ordinary differential equation. Some applications of this notion to soliton theory are presented.
Science Behind Thermography

Understanding the physical principles of electromagnetic radiation will help you avoid the pitfalls and develop a scientific, problem-solving approach to new applications in the growing field of thermography. The goal of this paper is to link working approximations to the formal theory, illustrating that an understanding of the origin of these approximations can be crucial to your success. In addition, a glossary of terms is presented to improve our literacy in this fascinating field of thermography.
Angular correlation in the π-μ-e decay of cosmic ray mesons

A measurement has been made of the angular correlation in the decay for mesons produced at high altitude by cosmic rays incident on a 22.4 liter emulsion stack. Within our statistics the angular distribution of the electrons is isotropic. The value of «a » in the expressiondN/dΩ = (l + a cos θ) is -.03 ± .04. This result is in diasgreement with the experiments using accelerator produced mesons which show a back-wards asymmetry with « a » = - .15 ± .02. Possible explanations for the difference are discussed.
The effect of interstimulation interval on the assessment and stability of kindled seizure thresholds

Two experiments were conducted to investigate the importance of the interstimulus interval (ISI) in the assessment of kindled seizure thresholds using an ascending method of limits. A third experiment examined the effect of varying the interval between successive threshold tests on threshold stability. No differences in afterdischarge (AD) or motor seizure (MS) threshold were observed when the ISI was either five minutes or 48 hours. However, a 30 second ISI yielded significantly higher AD and MS thresholds and shorter seizure duration compared to 1, 3, or 5 minute ISI's. AD and MS thresholds were found to be relatively stable over five successive tests when the inter-test interval was 48 hours. An inter-test interval of 24 hours, however, yielded progressively higher thresholds over the five tests.
Influence of vitamin E on polyamine metabolism in ozone-exposed rat lungs

The influence of vitamin E (E) on lung polyamine metabolism of rats exposed to ozone (O3) was examined. Rats fed diets wither E-deficient or supplemented with 1000 IU E/kg were exposed to 0.5 +/- 0.05 ppm O3 or filtered room air continuously for 5 days. They were then sacrificed and their lungs were analyzed for biochemical changes. Lung E content was strongly associated with the dietary level, and increased (36%, P less than 0.05) after O3 exposure only in E-supplemented rats. Lung polyamine metabolism was not affected in the air-control rats by E level, but increased after O3 exposure in both dietary groups. The activities of ornithine decarboxylase and S-adenosylmethionine decarboxylase were elevated above air controls. However, the increases were significant only for E-deficient rats when compared to E-supplemented rats. After O3 exposure, putrescine increased significantly in both dietary groups; spermidine increased but was significantly higher only in the E-deficient group; and spermine remained unchanged in both dietary groups. Elevated E content of supplemented rat lungs after O3 exposure may represent its mobilization under oxidant stress. Increased polyamine metabolism of E-deficient rats suggests either a greater sensitivity to injury by O3 or a possible antioxidant function for polyamines compensating for E deficiency.
Perchlorate removal by activated carbon adsorption

Abstract The adsorption of perchlorate on activated carbon was studied. A total of 10 types of commercial activated carbons were tested for perchlorate adsorption characteristics using pH as the master variable. The activated carbons were made from different base materials such as wood, bituminous coal, and lignite coal and thus expressed different surface characteristics such as specific surface area and surface charge, e.g. pHzpc. Adsorption isotherms were obtained in the pH range from 3 to 10 and perchlorate concentration from 0.01 to 1.0 mM. It was found that the adsorption isotherms followed the Langmuir type. Results showed that under the experimental conditions of the present study, surface charge not specific surface area was the most important factor governing perchlorate removal. All wood based activated carbons that had large variation in specific surface area, e.g. 3-fold, but very close pHzpc (surface charge) exhibited similar perchlorate adsorption capacity. On the other hand, the activated carbons having pHzpc > 8 exhibited higher adsorption capacity than those with low pHzpc of 2–3. This provided strong evidence of electrostatic forces as responsible for perchlorate adsorption. However electrostatics alone failed to explain the better perchlorate removal compared to other anions such sulfate and phosphate. The perchlorate adsorption on activated carbon was described by surface complexation model. Results of XPS and FT-IR studies showed that perchlorate adsorption at least partially occurs through specific interactions of perchlorate with surface functional groups. Results also demonstrated that specific chemical interactions between perchlorate and surface functional groups in combination with electrostatic forces were the major mechanism for perchlorate adsorption on activated carbon.
Applications of optical fiber sensors in the oil refining and petrochemical industries

Optical fiber distributed sensing technologies, consisting of many sensors in one single fiber, present unique and cost-effective solutions for the oil refining and petrochemical industries to optimize process operations and improve reliability and safety. In addition, optical fiber sensors do not require electrical power at the sensing locations, reducing the need for explosion-proof electronic packaging. This paper reviews state-of-the-art commercial optical fiber distributed temperature and strain sensing technologies, and presents challenges and opportunities for these technologies in the oil refining and petrochemical industries. Attention is drawn to the fundamental understanding of optical fiber materials and development of reliable sensor protection and installation methods for harsh environments.
Rapid crystallization of T4 lysozyme by intermolecular disulfide cross-linking

In an attempt to facilitate crystallization, engineered cysteines were used to promote formation of a 'back-to-back' dimer that occurs in different crystal forms of wild-type and mutant T4 lysozymes. The designed double mutant, N68C/A93C, in which the surface residues Asn68 and Ala93 were replaced by cysteines, formed dimers in solution and crystallized isomorphously to wild-type, but at a much faster rate. Overall, the mutant structure remained very similar to wild-type despite the formation of two intermolecular disulfide bridges. The crystals of cross-linked dimers ahd thermal factors somewhat lower than wild-type, indicating reduced mobility, but did not diffract to noticeably higher resolution. Introduction of the same cross-links was also used to obtain crystals in a different space group of a T4 lysozyme mutant that could not be crystallized previously. The results suggest that the formation of the lysozyme dimer is a critical intermediate in the formation of more than one crystal form and that covalent cross-linking of the intermediate accelerates nucleation and facilitates crystal growth. The disulfide cross-links are located on the 'back' of the molecule and formation of the cross-linked dimer appears to leave the active sites completely unobstructed. Nevertheless, the cross-linked dimer is completely inactive. One explanation for this behavior is that the disulfide bridges prevent hinge-bending motion that may be required for catalysis. Another possibility is that the formation of the dimer increases the overall bulk of the enzyme and prevents its access to the susceptible glycosidic bonds within the cell wall substrate.
Meta-Analysis of Lung Cancer in Asphalt Roofing and Paving Workers with External Adjustment for Confounding by Coal Tar

The study's objectives were to update Partanen's and Boffetta's 1994 meta-analysis of lung cancer among roofing and paving asphalt workers and explore the role of coal tar in explaining the statistical heterogeneity among these studies. Information retrieval strategies and eligibility criteria were defined for identifying the epidemiologic studies to be included in the analysis. The relative risk ratio (RR) for lung cancer was selected as the effect measure of interest. Coal tar bias factors were developed and used to externally adjust each eligible study's published RR for confounding by coal tar. Confidence intervals on adjusted RRs were estimated by the Monte Carlo methods outlined by Steenland and Greenland (2004). The meta-Relative Risk (meta-RR) and its variance were estimated by general variance-based methods. Heterogeneity of the RRs was assessed by heterogeneity chi-square and I 2 tests. Also explored were the influences of study design; differences between internally and externally adjusted RRs;...
Thermal analysis of multifacet-mirror ring resonator for XUV free-electron lasers

xUv (10 nm -100 nm) free-electron lasers (EELs) are potentially important light sources for advanced lithography and materials applications. The average power of an XUV EEL oscillator may be urnited by thermal loading of the resonator mirrors. We analyze the requirements for the thennal performance of the mirrors of a metal multifacet-mirror ring resonator for use at 12 nm. We use analytical methods and numerical approaches which include simulations with the 3-D EEL code FELEX. Thermal distortion of mirror surfaces leads to optical wavefront aberrations which reduce the focusability of the light beam in the gain medium (wiggler/electron beam) and limit the laser performance.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Ion energy distribution and gas heating in the cathode fall of a direct-current microdischarge

This paper reports on measurements of the ion energy distribution (IED) at the cathode of an argon dc microdischarge using energy-resolved molecular beam mass spectrometry. The measurements are conducted at a fixed pressure-electrode separation product (pd) of 1 cm Torr with a maximum discharge pressure of 20 Torr. The measured IED is compared to the theory of Davis and Vanderslice [W. D. Davis and T. A. Vanderslice, Phys. Rev. 131, 219 (1963)]. A higher pressure in a case of almost constant normalized current densities by pressure (Jp(-2) = 0.080+/-0.006 mA/cm(-2) Torr(-2)) yields a lower ratio of the ion mean free path to the sheath thickness. The results in almost constant Jp(-2) case then indicate that a scaling law of Jp(-2) is no longer applicable for IED of microdischarge. Expected background gaseous temperatures from IEDs with the collisional Child law have reasonable increasing with increased current density (J) in both cases of almost constant Jp(-2) and a constant pressure of 10 Torr. Supported by temperature measurement by laser absorption spectroscopy, it is demonstrated that the expanded theory might be applicable also to microdischarges (Ar approximately 20 Torr) with temperature adjusting.
Effect of Dextromethorphan, Diphenhydramine, and Placebo on Nocturnal Cough and Sleep Quality for Coughing Children and Their Parents

To the Editor. Paul et al1 did not prove that dextromethorphan and diphenhydramine are no better than placebo, because there was no placebo arm in their study. Sucrose is not a placebo. A placebo, by definition, is an inert substance, and sucrose has …
Paraspinal muscle reflex dynamics

Neuromuscular control of spinal stability may be represented as a control system wherein the paraspinal muscle reflex acts as feedback response to kinetic and kinematic disturbances of the trunk. The influence of preparatory muscle recruitment for the control of spinal stability has been previously examined, but there are few reported studies that characterize paraspinal reflex gain as feedback response. In the current study, the input-output dynamics of paraspinal reflexes were quantified by means of the impulse response function (IRF), with trunk perturbation force representing the input signal and EMG the output signal. Surface EMGs were collected from the trunk muscles in response to a brief anteriorly directed impact force applied to the trunk of healthy participants. Reflex behavior was measured in response to three levels of force impulse, 6.1, 9.2 and 12.0 Ns, and two different levels of external trunk flexion preload, 0 and 110 N anterior force. Reflex EMG was quantifiable in response to 91% of the perturbations. Mean reflex onset latency was 30.7+/-21.3 ms and reflex amplitude increased with perturbation amplitude. Impulse response function gain, G(IRF), was defined as the peak amplitude of the measured IRF and provided a consistent measure of response behavior. EMG reflex amplitude and G(IRF) increased with force impulse. Mean G(IRF) was 2.27+/-1.31% MVC/Ns and demonstrated declining trend with flexion preload. Results agree with a simple systems model of the neuromechanical feedback behavior. The relative contribution of the reflex dynamics to spinal stability must be investigated in future research.
Three Loop Balanced Bridge Feedback Pointing Control

The balanced bridge feedback (BBF) technique developed in communication engineering is applied to the multiloop pointing control priblem. Using colocated sensors, BBF decouples the motor loop from the mechanical plant and increases the feedback bandwidth in the motor and plant loops.
Histologic differences between orthotopic xenograft pancreas models affect Verteporfin uptake measured by fluorescence microscopy and spectroscopy

Photodynamic therapy (PDT) that uses the second generation photosensitizer, verteporfin (VP), is a developing therapy for pancreatic cancer. The optimal timing of light delivery related to VP uptake and distribution in pancreatic tumors will be important information to obtain to improve treatment for this intractable disease. In this work we examined uptake and distribution of VP in two orthotopic pancreatic tumors with different histological structure. ASPC-1 (fast-growing) and Panc-1 (slower growing) tumors were implanted in SCID mice and studied when tumors were approximately 100mm 3 . In a pilot study, these tumors had been shown to differ in uptake of VP using lightinduced fluorescence spectroscopy (LIFS) in vivo and fluorescence imaging ex vivo and that work is extended here. In vivo fluorescence mean readings of tumor and liver increased rapidly up to 15 minutes after photosensitizer injection for both tumor types, and then continued to increase up to 60 minutes post injection to a higher level in ASPC-1 than in Panc-1. There was variability among animals with the same tumor type, in both liver and tumor uptake and no selectivity of tumor over liver. In this work we further examined VP uptake at multiple time points in relation to microvascular density and perfusion, using DiOC 7 (to mark blood vessels) and VP fluorescence in the same tissue slices. Analysis of DiOC7 fluorescence indicates that AsPC-1 and Panc-1 have different vascular densities but AsPC-1 vasculature is more perfusive. Analysis of colocalized DiOC7 and VP fluorescence showed ASPC-1 with higher accumulation of VP 3 hrs after injection and more VP at a distance from blood vessels compared to Panc-1. This work shows the need for techniques to analyze photosensitizer distribution in order to optimize photodynamic therapy as an effective treatment for pancreatic tumors.
Nanoscale scanning probe ferromagnetic resonance imaging using localized modes

The discovery of new phenomena in layered and nanostructured magnetic devices is driving rapid growth in nanomagnetics research. Resulting applications such as giant magnetoresistive field sensors and spin torque devices are fuelling advances in information and communications technology, magnetoelectronic sensing and biomedicine. There is an urgent need for high-resolution magnetic-imaging tools capable of characterizing these complex, often buried, nanoscale structures. Conventional ferromagnetic resonance (FMR) provides quantitative information about ferromagnetic materials and interacting multicomponent magnetic structures with spectroscopic precision and can distinguish components of complex bulk samples through their distinctive spectroscopic features. However, it lacks the sensitivity to probe nanoscale volumes and has no imaging capabilities. Here we demonstrate FMR imaging through spin-wave localization. Although the strong interactions in a ferromagnet favour the excitation of extended collective modes, we show that the intense, spatially confined magnetic field of the micromagnetic probe tip used in FMR force microscopy can be used to localize the FMR mode immediately beneath the probe. We demonstrate FMR modes localized within volumes having 200 nm lateral dimensions, and improvements of the approach may allow these dimensions to be decreased to tens of nanometres. Our study shows that this approach is capable of providing the microscopic detail required for the characterization of ferromagnets used in fields ranging from spintronics to biomagnetism. This method is applicable to buried and surface magnets, and, being a resonance technique, measures local internal fields and other magnetic properties with spectroscopic precision.
Effect of p53 overexpression on radiation sensitivity of human colon cancer cells

Substantial controversy surrounds our understanding of the effect of p53 status on radiation sensitivity. To assess directly the role of p53 expression on radiation sensitivity, we chose a conditional expression system using a temperature-sensitive murine p53 that permitted each cell line to act as its own control. We found that the conditional expression of wild type p53 induced cell death (both apoptotic and nonapoptotic), changes in cell cycle distribution (arrest in G1 and G2, which resulted in a marked depletion of S-phase cells and an increase in the fraction of cells in G2), and an increase in the radiation resistance of G1 cells. These counterbalancing effects resulted in no significant effect on overall radiosensitivity. These findings demonstrate that wild type p53 function can produce a variety of effects that can modulate radiation sensitivity and may explain why p53 status alone has not been a strong predictor of radiosensitivity.
Theoretical morphology of developmental asymmetries

Summary Morphospaces are theoretical tools to explore the morphological organization of living and fossil organisms. They have been used mostly by the paleontological community in an effort to get the most out of one of the only pieces of evidence that fossil material usually provide: the morphology of hard parts. The expectation with the establishment of theoretical morphospaces is that, by abstracting and modeling the fundamental parts of form, the multiple processes that generate the phenotypes of embryonic and adult structures will be better understood. In this essay, we suggest that ontogenetic trajectories can be used as the generative functions that build morphospaces, and propose approaches to build theoretical models for the establishment of left–right asymmetries during vertebrate heart embryogenesis. BioEssays26:405–412,2004.2004WileyPeriodicals,Inc.