cssi/SciSciGPT-SciSciNet huggingface dataset:
Dynamics of atrioventricular nodal conduction ratios during conversion of 2:1 into 3:1, 4:1 and 5:1 atrioventricular block.

Abstract Previous work performed in our department and published in The American Journal of Cardiology discussed the dynamics of pacing-induced atrioventricular nodal or atrio (A):His (H) conduction ratios appearing during incremental atria1 stimulation at cycle lengths longer than those at which stable 2: 1 block was seen. 1 However, this report examines the dynamics of blocks occurring at even shorter cycle lengths, specifically when 2:1 block increases to higher degrees of block during the same pacing run.
Non‐linear systems and educational development in Europe

Educational change and improvement are constant processes. Practically every country in the world today is attempting to improve, reform, transform or change its educational system. The results of these development efforts have generally been disappointing. A general consensus seems to be that the gap between societal expectations and educational achievements is wide and becoming greater. The perceived failures of education are particularly difficult for political and educational leaders to understand given the massive influx of resources invested in educational systems in recent years. This is a result of a linear expectation wherein output is proportional to the input. Non‐linear theory, proposed in this paper as a more valid way of conceptualizing educational development efforts, does not assume this proportional relationship. This paper addresses non‐linear theory by using it to examine educational development efforts in Western and Eastern European nations.
Optimizing Instructional Video for Preservice Teachers in an Online Technology Integration Course.

This study assessed the effect of design instructional video based on the Cognitive Theory of Multimedia Learning by applying segmentation and signaling on the learning outcome of students in an online technology integration course. The study assessed the correlation between students’ personal preferences (preferred learning styles and area of specialization) and their learning outcomes. A three-group pretest–posttest design was employed to assess whether there were significant differences in students’ test scores after they watched an instructional video. The results of the analysis of covariance (ANCOVA) analysis indicate that instructional design had a significant effect on students’ learning outcome. This effect was demonstrated by the statistically significant differences in students’ learning outcomes, with the highest scores achieved by students in the segmented and signaled video group and the lowest scores in the no-segmentation and no-signaling group. Moreover, results indicate that students’ le...
A bicontinuous tetrahedral structure in a liquid-crystalline lipid

The structure of most lipid–water phases can be visualized as an ordered distribution of two liquid media, water and hydrocarbons, separated by a continuous surface covered by the polar groups of the lipid molecules1. In the cubic phases in particular, rod-like elements are linked into three-dimensional networks1,2. Two of these phases (space groups Ia3d and Pn3m) contain two such three-dimensional networks mutually inter-woven and unconnected. Under the constraints of energy minimization3, the interface between the components in certain of these ‘porous fluids’ may well resemble one of the periodic minimal surface structures of the type described mathematically by Schwarz4,5. A structure of this sort has been proposed for the viscous isotropic (cubic) form of glycerol monooleate (GMO) by Larsson et al.6 who suggested that the X-ray diagrams of Lindblom et al.7 indicated a body-centred crystal structure in which lipid bilayers might be arranged as in Schwarz's octahedral surface4. We have now found that at high water contents, a primitive cubic lattice better fits the X-ray evidence with the material in the crystal arranged in a tetrahedral way. The lipid appears to form a single bilayer, continuous in three dimensions, separating two continuous interlinked networks of water. Each of the water networks has the symmetry of the diamond crystal structure and the bilayer lies in the space between them following a surface resembling Schwarz's tetrahedral surface4.
Effect of epitaxial strain on the spontaneous polarization of thin film ferroelectrics

Epitaxial strain can substantially enhance the spontaneous polarizations and Curie temperatures of ferroelectric thin films compared to the corresponding bulk materials. In this Letter we use first principles calculations to calculate the effect of epitaxial strain on the spontaneous polarization of the ferroelectrics ${\mathrm{BaTiO}}_{3}$, ${\mathrm{PbTiO}}_{3}$, and ${\mathrm{LiNbO}}_{3}$, and the multiferroic material ${\mathrm{BiFeO}}_{3}$. We show that the epitaxial strain dependence of the polarization varies considerably for the different systems, and in some cases is, in fact, very small. We discuss possible reasons for this different behavior and show that the effect of epitaxial strain can easily be understood in terms of the piezoelectric and elastic constants of the unstrained materials. Our results provide a computational tool for the quantitative prediction of strain behavior in ferroelectric thin films.
The role of automatic identification (auto ID) in the computer integrated manufacturing (CIM) architecture

Abstract Time availability of manufacturing information in the right place and in a usable format has a direct bearing on how organization resources are used to effect the required value-added activities on a product to impart economic value to the end product. The CIM architecture provides a definition and structure to tail or the knowledge base for easy access and utilization to accomplish organizational goals. Most organizations have pockets of localized information domains stemming from individual or group innovativeness in their efforts to overcome obstacles in any given project. Unfortunately, most of this information is not tapped and further disseminated for use at a later time to solve similar problems. There is thus a need, within the CIM architecture construct, for complete and flexible information flow, capturing the procedures for each task. Once capture, timely distribution is required to enable decisions to be made based on up-to-date information. A number of Automatic identification (Auto ID) technologies exist to aid in dealing with informtion capture and dissemination in an automated manufacturing environment, and thus facilitate implementation of the CIM architecture, to address the time value of information in decision making. This paper will examine how Auto ID technologies such as bar code technology, radio frequency technologies and others fit into the structure of CIM architecture, to provide the informational relationships in an organization to link at the facets of the CIM architecture, and provide the knowledge required for the organization to be competitively productive.
The Ethics of Competition

The Ethics of Competition is a book of Frank H. Knight's writings on a common theme: the problem of social control and its various implications. Knight believed in free economic institutions but was also aware that the competitive economic system could be improved. One of the central figures of neoclassical economics in the twentieth century, Knight pursued a lifelong campaign against irrationalities of nationalism, religious fanaticism, and group conflict, while conceding that these were fundamental orientations of human action that might yet frustrate his own work as an economist. While Knight vigorously defended human freedom and the liberal order, he also was sufficiently moved by the shortcomings of liberalism as to condemn it as rife with abuse. As Richard Boyd writes in the new introduction, The Ethics of Competition is nothing short of visionary. Knight foresaw virtually all of the reductionistic tendencies that have come to plague the discipline he cultivated, neoclassical economic theory. Even more impressively, Knight related these disciplinary proclivities back to themes as grand as the fate of liberal democracy and human nature. Boyd discusses Knight's belief that the human craving for simple, mechanical explanations inevitably leads to frustration rather than material satisfaction. Chapters in The Ethics of Competition include "Economic Psychology and the Value Problem," "The Limitations of Scientific Method in Economics," "Marginal Utility Economics," "Fallacies in the Interpretation of Social Cost," and "Economic Theory and Nationalism." This volume will be of essential value to economists, political theorists, philosophers, and sociologists.
Qualitative kinetics of electron transfer reactions

Abstract We revise the conventional theory of electron transfer reactions and give a qualitative picture of the turnover from non-adiabatic to adiabatic regime consistent with the general principle that equilibrium properties can depend on no kinetic parameters. It is shown that if the solvent polarization fluctuations are fast enough then the reaction is non-adiabatic and the solvent follows the instantaneous charge distribution. No kinetic characteristics of the solvent enters the expression for the rate constant which in this case is determined by the total reorganization energy of the system. If a slow component of polarization fluctuations can be identified then a high frequency dielectric permittivity of the solvent can be introduced self-consistently. In the normal region the reaction is adiabatic and the charge distribution follows the solvent polarization relaxation in the potential which has the form of the free energy of the two level system with no interaction between the states at fixed value of the slow reaction coordinate. In this regime the reaction rate is determined by the reorganization energy of the slow degrees of freedom. It is also shown that in the inverted region the reaction can never be adiabatic.
Investigation of the Silicon Nitride on Hydrogenated Amorphous Silicon Interface

We report on our investigation of the silicon nitride on hydrogenated amorphous silicon interface by high frequency capacitance-voltage measurements. We show evidence for the existence of a large number of interface states at energies less than or equal to 0.36 eV below the hydrogenated amorphous silicon conduction band. In addition, we demonstrate that the states responsible for the hysteresis in capacitance-voltage characteristics are located in the silicon nitride layer. Finally, we argue that the ability of hydrogenated amorphous silicon to act as hole diffusion barrier is responsible for the observed flat-band voltage shift.
A simplified capillary buret with reagent generation by means of ion exchange resins

A simple capillary buret equipped with reservoir and semi-automatic filling is described. It may also be equipped with ion exchange columns that serve to generate standard acid or base during titration, allowing a simple potassium chloride solution to serve as the only standard solution for either acid or base titrations. The possibilities of adapting it to automatic generation of solutions other than acid or base are discussed, as well as its possible use as an automatic titrating buret.
Phenylmethylsulfonyl fluoride (PMSF) inhibits nerve growth factor binding to the high affinity (type I) nerve growth factor receptor

Summary Dorsal root ganglia were extirpated from 9-day old embryonic chickens and solubilized in phosphate buffered saline containing 0.5% Noniodet P 40 detergent. When nerve growth factor binding studies are performed on these samples, the expected curvilinear Rosenthal (Scatchard) plot is obtained. However, when the solubilized cell sample is made 1–2 m M in phenylmethylsulfonyl fluoride and nerve growth factor binding is determined, a linear Rosenthal (Scatchard) plot is obtained. The equilibrium dissociation constant obtained from the slope of the line is 1.9 × 10 −9 M , identical to the equilibrium dissociation constant of the low affinity receptor. A similar phenomenon is observed when rat pheochromocytoma cells are solubilized in the non-ionic detergent and nerve growth factor binding is determined. No high affinity binding can be detected for either cell type when detergent solubilized cells are incubated with phenylmethylsulfonyl fluoride.
Polymorphisms of the TAP2 gene may influence antibody response to live measles vaccine virus.

The transporter associated with antigen processing (TAP) gene products transport peptides from the cytosol to the endoplasmic reticulum for processing by the immune system. We hypothesized that polymorphisms within the TAP genes may influence measles vaccine antigen processing and hence antibody response. TAP genotypes were determined for subjects who were measles vaccine nonresponders (n=32) and hyper-responders (n=28). TAP1 and TAP2 alleles were determined by PCR amplification of specific alleles (PASA). Measles vaccine nonresponders were more likely to be homozygous at TAP2 position 665 than were hyper-responders (OR=5.0, P=0.016). Lastly, a trend was found in the overall distribution of all TAP2 genotype frequencies between hyper-responders and nonresponders (P=0.08). No association was found between TAP1 polymorphisms and vaccine response. These data reveal an association between TAP2 genotype and measles vaccine antibody response which may explain one mechanism behind vaccine failure.
Upper and lower urinary tract outcome after surgical repair of cloacal malformations: a three-decade experience.

The three papers in this section cover a wide range of subjects. Authors from Indianapolis present a three-decade experience in upper and lower urinary tract outcomes after the surgical repair of cloacal malformations. An objective assessment of their results of hypospadias surgery is described by authors from Manchester. Finally, the question is asked by authors from Athens; is bladder muscle decompensation in boys with a history of PUV caused by secondary bladder neck obstruction? OBJECTIVE To report the urological outcome of the surgical correction of persistent cloaca, which is technically demanding and may require many procedures in an effort to preserve renal function and provide urinary continence. PATIENTS AND METHODS A retrospective chart review from 1971 to 2003 identified 23 patients with cloacal malformations (two posterior, 21 classical) that were reconstructed. The confluence of the urethra, vagina and rectum was noted to be high in 16, low in five and unknown in two; one patient was a conjoined twin. RESULTS The mean (range) follow-up was 9.3 (0.4–31.6) years. Urinary anomalies included 14 patients with renal anomalies (six solitary kidneys, four renal dysplasia, two pelvi-ureteric junction, one each duplex and crossed fused) and two duplicated bladders. Vesico-ureteric reflux was present in 13 patients (57%), hydronephrosis at birth in 13, a bony vertebral abnormality in 14 and the VACTERL association in four. Total urogenital mobilization (TUM) was used in six patients and spinal cord untethering in four; a nephrectomy was required in three and partial nephrectomy in one. Upper tract dilation was still present in six patients. Age-adjusted creatinine levels were abnormal in four (18%) patients and borderline in another six (26%). In the nine patients with a solitary kidney (six solitary, three after nephrectomy), the age-adjusted creatinine level was abnormal in two and borderline in four. A vesicostomy was initially performed in 11 patients. The method of bladder emptying is known in 22; 10 void, 11 require clean intermittent catheterization (five abdominal stoma, six urethral) and one was diverted with a conduit. Of the 18 patients aged > 47 months 15 were continent (14 complete > 4 h, one partial 2–4 h), and three are wet (one conduit). Reconstruction of the lower urinary tract included four bladder augmentations (one ureteric, one ileal, two colon), five bladder neck procedures (two artificial sphincter, one each bladder neck repair, sling, bladder neck division) and six catheterizable channels (one now with a colon conduit). The ureters were re-implanted in 12 patients. CONCLUSION Although the surgical correction of this rare malformation is complex, the upper urinary and lower urinary tract outcome can be favourable, albeit after several reconstructive procedures. TUM has emerged as the primary method for vaginal reconstruction, but the long-term lower tract outcome after this procedure is awaited.
The Profit Rate as a Measure of Monopoly Power

The meaning of monopoly, 271. — The problem of measurement, 272. — Theoretical excess profits as indicators of monopoly, 273. — The problem of defining the rate of excess profit, 275. — Definition of the rate for a short fiscal period, 277. — The quantity of assets which a competitive firm will hold, 281. — The relation of the accounting to the theoretical rate of profit, 289. — The accounting profit rate as a measure of monopoly power, 291.
Experimental investigation of laser hot-wire cladding:

Laser cladding by cold-wire feeding is known as an efficient cladding method due to its advantages, such as near 100% material utilization, high deposition rate, and flexible adaptation to the clad...
Helical Computed Tomographic Scan in the Evaluation of Mediastinal Gunshot Wounds

Background: The standard evaluation of mediastinal gunshot wounds usually requires angiography and either esophagoscopy or esophagography. In the present study, we have evaluated the role of helical computed tomographic (CT) scanning in reducing the need for angiographic and esophageal studies. Methods: This was a prospective study of patients with mediastinal gunshot wounds who were hemodynamically stable and would otherwise require angiography and esophageal evaluation. All patients underwent CT scan of the chest with intravenous contrast to delineate the missile trajectory. If the missile tract was in close proximity to the aorta, great vessels, or esophagus, then traditional evaluation with angiographic or esophageal evaluation was pursued. Results: A total of 24 patients met the inclusion criteria and underwent CT scan evaluation of their mediastinal gunshot wounds. One patient was taken for sternotomy to remove a missile embedded in the myocardium solely on the basis of the result of the CT scan. Because of proximity of the bullet tract, 12 patients required additional evaluation with eight angiograms and nine esophageal studies. One of these patients had a positive angiogram (bullet resting against the ascending aorta) and underwent sternotomy for missile removal; all other studies were negative. The remaining 11 patients were found to have well-defined missile tracts that approached neither the aorta nor the esophagus, and no additional evaluation was pursued. There were no missed mediastinal injuries in this group. Overall, 12 of 24 patients (50%) had a change in management (either received an operation or avoided additional radiographic or endoscopic evaluation) on the basis of the CT scan. Conclusion: The helical CT scan provides a rapid, readily available, noninvasive means to evaluate missile trajectories. This permits accurate assessment of potential mediastinal injury and reduces the need for routine angiographic and esophageal studies.
Identification of estrogen-modified nucleosides from calf thymus DNA reacted with 6-hydroxyestrogen 6-sulfates.

Two estrogen sulfates, pyridinium 3-methoxyestra-1,3,5(10)-trien-6α-yl sulfate (3MeE-6α-S) and its 6β-isomer (3MeE-6β-S), synthesized as model compounds to demonstrate the carcinogenesis of estrogen, were found to react with calf thymus DNA to produce steroid-modified DNA adducts. Digestion of the DNA by nuclease P1 and phosphodiesterase I followed by alkaline phosphatase gave a deoxyribonucleoside fraction, of which N2-[3-methoxyestra-1,3,5(10)-trien-6α-yl]deoxyguanosine, N2-[3-methoxyestra-1,3,5(10)-trien-6β-yl]deoxyguanosine, N6-[3-methoxyestra-1,3,5(10)-trien-6β-yl]deoxyadenosine, and N6-[3-methoxyestra-1,3,5(10)-trien-6α-yl]deoxyadenosine (identified as a base adduct) were identified using HPLC by comparing them with authentic specimens prepared by reacting dG and dA with both sulfates. No steroid−dC adduct was detected in the digestion products of the DNA adduct, although dC reacted with the sulfates to form N4-[3-methoxyestra-1,3,5(10)-trien-6β-yl]deoxycytidine. These results mean that estrogen 6-s...
INCREASED PRESENCE OF INTERLEUKIN-6 (IL-6) AND IL-8 SECRETING FIBROBLAST SUBPOPULATIONS IN ADULT PERIODONTITIS

Periodontitis is a chronic inflammation of the supporting structures of the dentition which constitutes one of the most common causes of adult tooth loss. While certain microorganisms have been associated with the onset of the disease process, the exact pathogenetic mechanisms underlying periodontal destruction are still poorly understood. We have tested the hypothesis that gingival fibroblasts from diseased sites contribute to pathogenesis by possessing a secretory phenotype characterized by an exuberant secretion of inflammatory mediators and cytokines. Of the cytokines and mediators tested, fibroblast IL-1beta and prostaglandin E2 (PGE2) secretion was not different between health and disease. However, we have shown that fibroblasts from periodontal lesions produce in vitro greater amounts of IL-6 and IL-8 constitutively than healthy controls. When fibroblasts were stimulated with a panel of endogenous or exogenous response modifiers, the magnitude of cytokine and mediator stimulation above constitutive levels did not differ between health and disease. A strong positive correlation was identified between IL-6 or IL-8 constitutive secretion levels in vitro and the in situ expression of these cytokines within the connective tissues from where these cells originated, indicating that the in vitro phenotype mirrors their in vivo function. Furthermore, we present evidence which indicates that increased cytokine secretion by fibroblasts in disease is due to an elevated proportion of subpopulations with higher cytokine secretory capacity. Finally, we demonstrated that cultures from diseased sites are composed of cells with higher levels of constitutive CD40 expression, which may contribute to the increased IL-6 and IL-8 secretory phenotype.
Testing for Indeterminacy: An Application to U.S. Monetary Policy: Reply

This paper considers a prototypical New Keynesian model, in which the equilibrium is undetermined if monetary policy is "passive." The likelihood-based estimation of dynamic equilibrium models is extended to allow for indeterminacies and sunspot fluctuations. We construct posterior weights for the determinacy and indeterminacy region of the parameter space and estimates for the propagation of fundamental and sunspot shocks. According to the estimated model, U.S. monetary policy post-1982 is consistent with determinacy, whereas the pre-Volcker policy is not. We find that before 1979 indeterminacy substantially altered the propagation of shocks.
Synthesis, structure and magnetic studies of copper(II) and copper(I) complexes of methylpyrazines

Abstract Reaction of Cu(ClO4)2 with 2-methylpyrazine (mepz), 2,5-dimethylpyrazine (2,5-dmpz) or 2,6-dimethylpyrazine (2,6-dmpz) in aqueous solution yields the corresponding CuLn(ClO4)2(H2O)m (n = 2,4; m = 1,2,4). Single-crystal X-ray diffraction of Cu(mepz)2(ClO4)2(H2O)2 (1) reveals a roughly octahedral geometry with all ligands trans. Similarly, Cu(mepz)4(ClO4)2(H2O) (2) is pseudo-octahedral with one coordinated perchlorate and one H2O in the axial sites. The pyrazines are coordinated through the N(4) nitrogen atom in both 1 and 2. The magnetic susceptibilities of these compounds have been measured in the range 2–300 K. All the compounds behave as paramagnets. Conversely, reaction of Cu(ClO4)2 with 2,3-dimethylpyrazine in aqueous solution, or with mepz, 2,3-dmpz or 2,5-dmpz and NaBH4 or NaSCN in aqueous solution yields complexes of the type Cu2(L)3(ClO)4)2 or Cu2(L)(SCN)2, respectively. IR analysis suggests that the complexes are polymeric lattices of tri-coordinate copper(I) atoms bridged by the pyrazine ligands or the pyrazine and thiocyanate ligands, similar to the known structure of Cu2(2,3-dimethylpyrazine)3(ClO4)2.
Heterodox Political Economy and the Degrowth Perspective

The transition to sustainability will be difficult. Environmental sustainability entails living within the Earth’s limits, yet the majority of scientific studies indicate a condition of overshoot. For mainstream economists sustainability means perpetuating economic growth. Consequently, environmental and economic sustainability are incompatible in the present institutional context. This paper seeks to develop a new theory of sustainability based upon historical and institutional contexts, the role of economic crises, as well as focusing upon energy quality and meaningful work. Mainstream economics, which emphasizes market self-regulation and economic growth, is not a good vehicle for a theory of sustainability. Better insights are to be found in the literature of heterodox political economy and political ecology. Political ecology is based upon the theory of monopoly capital. Monopoly capitalism exhibits a tendency towards stagnation, because the economic surplus cannot be absorbed adequately in the absence of system-wide waste. The Monthly Review School continues this tradition in the context of the metabolic rift, while the Capitalism, Nature and Socialism School develops the idea of a second contradiction of capitalism. The Social Structure of Accumulation school pursues the idea of long swings of economic activity based upon institutional structures that aid or inhibit capital accumulation.
Electromagnetic Compatibility of PSK–OOK Digital Fiber Communications

This study deals with an electromagnetic compatibility (EMC) problem of fiber cable in disturbing electric field. Lightwaves that emerge from the output endface of the fiber are intensity modulated, phase shifted, or modulation frequency multiplied under special conditions. In this paper, theoretical investigation of the effect of interfering electric fields on the bit error rate of digital signals propagating originally in an optical fiber is presented for the EMC evaluation. Theoretical analysis and specific numerical examples show that depending on the required EMC level, the unshielded fiber may not be immune to interference of electromagnetic fields.
Effectiveness of Various Light Sources on the Stimulation of Phosphorescent Safety Markings

Commercially available phosphorescent materials are experimentally evaluated under conventional and solid-state lighting sources. The spectral and photopic properties of the sources are considered against the current ASTM test method for photoluminescent safety markings.
A branch and bound algorithm with constraint partitioning for integer goal programming problems

Abstract Using constraint partitioning and variable elimination, the authors have recently developed an efficient algorithm for solving linear goal programming problems. However, many goal programs require some or all of the decision variables to be integer valued. This paper shows how the new partitioning algorithm can be extended with a modified branch and bound strategy to solve both pure and mixed type integer goal programming problems. A potential problem in combining the partitioning algorithm and the branch and bound search scheme is presented and resolved.
Identification of Traumatic Stress Reactions in Women at Increased Risk for Breast Cancer

It has been shown that the diagnosis and treatment of cancer may constitute a traumatic event that generates in patients and some of their family members traumatic reactions that are consistent with the symptom profile of posttraumatic stress disorder (PTSD). The present study was conducted to establish the degree to which women at increased familial risk for breast cancer showed such traumatic reactions and to establish which demographic or psychological variables may contribute to the experience of such traumatic reactions in at-risk individuals. Seventy-three women from the Revlon UCLA Breast Center High Risk Clinic were assessed for traumatic reactions that might be consistent with the DSM-IV criteria for PTSD. The results showed that women at increased risk for breast cancer exhibited traumatic responses similar to those reported by cancer patients. When the authors used a self-report instrument that maps onto DSM-IV criteria, 4% of the study subjects reported symptoms consistent with criteria for a potential diagnosis of PTSD, and an additional 7% of the subjects reported symptoms consistent with potentially subclinical levels of PTSD, according to DSM-IV criteria.
Compensating Civilians during War: A Place for Individuals in International Law

Although civilian immunity is among the most widely agreed-upon norms of war, civilians are often attacked in contemporary conflicts. To some extent, the harm may be mitigated by programs to compensate the victims of wars. This article explores the three legal statutes and two forms of direct payment that the United States uses to compensate civilians harmed in wars and argues that although these are improvements in the treatment of civilians, they are inadequate. We argue that an individual cause of action in international law would provide a much better means of allowing civilians harmed by wars to seek compensation.
Trench and compact structures for dRAMs

There have been a large variety of trench based dRAM cells proposed in the last few years. This paper attempts to establish the requirements of a 4Megabit cell and classify the various trench based approaches. The original trench capacitor and its limitations are described and three classes of trench capacitors that attempt to overcome these limits are described. The first is the inside out capacitor where the roles of the storage electrode and the cell plate are interchanged. In the second class the trench serves to isolate as well as increase the available storage area. The third type builds a two concentric plates inside the trench. These can be attached to a planer transistor or a trench transistor to form a large number of combinations. These concepts are graded according to probability of success.
Web site addresses global drinking water crisis

A new Web resource provides the public with peer-reviewed scientific and technical information about the need for safe drinking water and strategies to enhance the safety and availability of water supplies around the world. Developed by the U.S. National Academy of Sciences (NAS) and the Global Health and Education Foundation, the “Safe Drinking Water is Essential” Web site (http://www.drinking-water.org) presents data and case studies written for a lay audience and aims to provide international decision-makers with tools to solve local water quality problems. More than 1 billion people worldwide do not have access to safe drinking water. However, “many of the approaches and technologies needed to improve drinking water quality already exist,” said Ralph J. Cicerone, NAS president.
Role of Soil, Crop Debris, and a Plant Pathogen in Salmonella enterica Contamination of Tomato Plants

In the U.S., tomatoes have become the most implicated vehicle for produce-associated Salmonellosis with 12 outbreaks since 1998. Although unconfirmed, trace backs suggest pre-harvest contamination with Salmonella enterica . Routes of tomato crop contamination by S. enterica in the absence of direct artificial inoculation have not been investigated. This work examined the role of contaminated soil, the potential for crop debris to act as inoculum from one crop to the next, and any interaction between the seedbourne plant pathogen Xanthomonas campestris pv. vesicatoria and S. enterica on tomato plants. Our results show S. enterica can survive for up to six weeks in fallow soil with the ability to contaminate tomato plants. We found S. enterica can contaminate a subsequent crop via crop debris; however a fallow period between crop incorporation and subsequent seeding can affect contamination patterns. Throughout these studies, populations of S. enterica declined over time and there was no bacterial growth in either the phyllosphere or rhizoplane. The presence of X. campestris pv. vesicatoria on co-colonized tomato plants had no effect on the incidence of S. enterica tomato phyllosphere contamination. However, growth of S. enterica in the tomato phyllosphere occurred on co-colonized plants in the absence of plant disease. S. enterica contaminated soil can lead to contamination of the tomato phyllosphere. A six week lag period between soil contamination and tomato seeding did not deter subsequent crop contamination. In the absence of plant disease, presence of the bacterial plant pathogen, X. campestris pv. vesicatoria was beneficial to S. enterica allowing multiplication of the human pathogen population. Any event leading to soil contamination with S. enterica could pose a public health risk with subsequent tomato production, especially in areas prone to bacterial spot disease.
The effects on metalinguisticawareness of an experimental bilingual program for deaf children

This article reports on an investigation of the effects of an experimental bilingual ASL/English syllabus on metalinguistic awareness for young deaf children. A special curriculum was created, centering on the telling of stories first in ASL only, and later in both ASL and English. The purpose was to improve metalinguistic awareness as represented by an ability to distinguish between the two sign language varieties of ASL and signed English. The curriculum was piloted 2 to 5 hours a week for 14 months with a group of kindergarten children at a residential school for the deaf. Each subject was matched with a control child at another school where the experimental program was not taught. The children were given pre- and posttests for metalinguistic ability. Results indicated that the exposure to the syllabus increased metalinguistic skills significantly for the experimental group, but that the control group experienced no such increase.
Diffusion-limited aggregation: Connection to a free-boundary problem and lattice anisotropy.

We study the relationship of diffusion-limited aggregation (DLA) simulations to the solutions of a free-boundary problem that is used to model crystal growth in two spatial dimensions. The mathematical connection between the DLA hitting probability and the normal derivative to the boundary of a growing aggregate is made with particular attention to the lattice anisotropy that systematically appears. Modifications of the original DLA simulation are considered, and the influence of these modifications on the expected growth shape anisotropy is discussed. We present the results of simple DLA and modified DLA simulations. We use a histogramming technique, similar to that used by Arneodo et al. for viscous fingering simulations, to display clearly the preferred growth directions of the various simulations. This gives some indication of the effect of simulation modifications on the growth shape anisotropy. We find that both the multiple-hit simulation with erasing, and the multiple-hit simulation without erasing (sometimes referred to as noise-reduced DLA) actually enhance growth shape anisotropy. We conclude that DLA-like simulations do not, in general, provide accurate approximate solutions to the continuum model of crystal growth. (c) 1995 The American Physical Society
Effect of geometry on thermoelastic damping in MEMS

The effects of geometry on the energy dissipation induced by thermoelastic damping in MEMS resonators are investigated numerically using a finite element formulation. The perturbation analysis is applied to derive a linear eigenvalue equation for the exponentially decaying rate of the mechanical oscillation. The analysis also involves a Fourier method that reduces the dimensionality of the problem and considerably improves the computational efficiency. The method is first validated by comparing the two-dimensional model to the existing analytical solutions for a simply supported beam system, and then it is extended to a three-dimensional axisymmetric geometry to obtain the energy loss as a function of the geometric parameters in a silicon ring resonator. The computational results reveal that there is a peak value for the resonant frequency when the radial width of the ring varies. In addition, the quality factor (Q-factor) decreases with the radial width as a monotonic function.
Variation of upwelling/oceanic conditions during the latest Pleistocene through Holocene off the central Peruvian coast: A diatom record

Diatoms are well preserved in partly laminated Holocene and late Pleistocene sediments on the upper continental slope of central Peru. Accumulation rates of diatom species previously recognized as tropical (oceanic, warm water) and subtropical (neritic, cooler water, upwelling) changed markedly downcore in Kasten cores obtained at 11°15′S, 12°58′S, and 13°37′S latitude. Subtropical species (e.g., Thalassiosira eccentrica “group”, Thalassiothrix frauenfeldii, Chaetoceros spp. resting spores, Delphineis spp.) predominated in late Pleistocene sediments of the two southern cores. A mix of tropical and subtropical diatom assemblages occurred in latest Pleistocene sediments, while tropical species (e.g., Coscinodiscus nodulifer/radiatus, Pseudoeunotia doliolus, Thalassionema nitzschioides var. parva) predominated in the late Holocene sediments. In the northern core latest Pleistocene sediments also contained a mix of tropical and subtropical species. Similarly, late Holocene sediments contained predominately tropical species of diatoms. Neoglacial periods (200–400 yr B.P., 2000–2700 yr B.P.), however, were sometimes characterized by a greater abundance of subtropical species and punctuated periodically with blooms of Skeletonema costatum and Rhizosolenia shrubsolei. It is proposed that during times of Southern Hemisphere cooling, Peruvian coastal waters north of 12°S were subjected to episodic mixing with warmer water masses before being overwhelmed by tropical waters that may have either passed southward across a weakened Equatorial Front or arose from intensified offshore countercurrents. Coastal waters south of 12°S latitude were probably unaffected by the tropical influence. Rather, these waters may have undergone intensified upwelling during the last Glacial epoch.
The Development and Effects of an Upper Extremity Exercise Program Based on Patterned Sensory Enhancement for Home-bound Stroke Patients

Purpose: This study was conducted to develop and assess the feasibility of an upper extremity exercise program based on Patterned Sensory Enhancement (PSE) for home-bound stroke patients by measuring the level of upper extremity function, depression, and interpersonal relationship. Methods: The experiments were performed on stroke patients at three different rehabilitation centers in Incheon City. Twenty patients participated in the experimental group or in the control group. The program was executed three times a week for 6 weeks. Data were collected from August to October, 2006. Manual Function Test was used to quantify and evaluate upper extremity function. The depression level and the effectiveness of interpersonal relationship were quantified and measured using CES-D and Interpersonal Relationship Scale, respectively. Results: The effectiveness of upper extremity function of stroke patients who participated in the PSE upper extremity exercise program was higher than that of non-participating patients. The depression level decreased and interpersonal relationship improved in the stroke patients who participated in this program compared to those who did not. Conclusion: These findings prove that the PSE upper extremity exercise program for home-bound stroke patients was an effective strategy for enhancing upper extremity function, decreasing the depression level, and improving interpersonal relationships.
Child welfare services involvement among the children of young parents in foster care

Despite the high rate of early parenthood among youth in foster care as well as the increased risk of child maltreatment among children whose adolescent parents have been neglected or abused, very little is known about child welfare services involvement among children whose parents were in foster care when they were born. This study uses administrative data from the Illinois Department of Children and Family Services (DCFS) to examine the occurrence of child abuse and neglect investigations, indicated reports and out of home care placements among the children of youth in foster. Thirty-nine percent of the children were the subject of at least one CPS investigation, 17 percent had at least one indicated report and 11 percent were placed in out of home care at least once before their 5th birthday. Cox proportional hazard models are also estimated to identify characteristics of parenting foster youth and their placement histories associated with the risk of child welfare services involvement. Implications of the findings for policy and practice are discussed.
The use of a predicted CPAP equation improves CPAP titration success.

Titration of continuous positive airway pressure (CPAP) is performed to determine the CPAP setting to prescribe for an individual patient. A prediction equation has been published that could be used to improve the success rate of CPAP titrations. The goals of this study were: (1) to test the hypothesis that the use of the prediction equation would achieve a higher rate of successful CPAP titrations; (2) to validate the equation as an accurate predictor of the prescribed CPAP setting and determine the factors that influence the accuracy of the prediction equation. A total of 224 patients underwent CPAP titration prior to using the equation, with a starting pressure of 5 cm H2O. A total of 192 patients underwent CPAP titration using the equation-predicted CPAP level as the starting pressure (median starting pressure of 8 cm H2O [interquartile range 7, 10 cm H2O]). The percentage of successful studies, as defined by a 50% decrease in the apnea–hypopnea index (AHI) and a final AHI ≤10 cm H2O, increased from 50% to 68% (p<0.001), while the number of patients who were prescribed a CPAP level that had not been tested decreased from 22% to 5% (p<0.001). The equation was not accurate in predicting the prescribed level of CPAP, with only 30.8% of the patients with a prescribed pressure ≤3 cm H2O of the predicted pressure. Female gender was the only predictor of a prescribed pressure ≤3 cm H2O from the predicted pressure (odds ratio 3.45, 95% confidence intervals 1.67, 7.13, p<0.001). A CPAP prediction equation modestly increases the rate of successful CPAP titrations by increasing the starting pressure of the titration. The equation does not accurately predict the prescribed CPAP level, reaffirming the need for a titration study to determine the optimal prescribed level in a given patient.
Pairwise agonist scanning predicts cellular signaling responses to combinatorial stimuli

Prediction of cellular response to multiple stimuli is central to evaluating patient-specific clinical status and to basic understanding of cell biology. Cross-talk between signaling pathways cannot be predicted by studying them in isolation and the combinatorial complexity of multiple agonists acting together prohibits an exhaustive exploration of the complete experimental space. Here we describe pairwise agonist scanning (PAS), a strategy that trains a neural network model based on measurements of cellular responses to individual and all pairwise combinations of input signals. We apply PAS to predict calcium signaling responses of human platelets in EDTA-treated plasma to six different agonists (ADP, convulxin, U46619, SFLLRN, AYPGKF and PGE(2)) at three concentrations (0.1, 1 and 10 x EC(50)). The model predicted responses to sequentially added agonists, to ternary combinations of agonists and to 45 different combinations of four to six agonists (R = 0.88). Furthermore, we use PAS to distinguish between the phenotypic responses of platelets from ten donors. Training neural networks with pairs of stimuli across the dose-response regime represents an efficient approach for predicting complex signal integration in a patient-specific disease milieu.
Solid phase synthesis of polynucleotides. VIII. Synthesis of mixed oligodeoxyribonucleotides by the phosphotriester solid phase method1

A solid phase method for the simultaneous synthesis of mixed oligonucleotides using a phosphotriester approach has been developed. For this synthesis, a mixture of mono or dimeric coupling units is used, and a slight difference in the reactivity of those units is found. However, this difference does not hamper the simultaneous, mixed oligonucleotide synthesis, and the sequence analysis of a product demonstrates the existence of all desired sequences in the final mixture.
Influence of different automated peritoneal dialysis schedules on solute and water removal.

patients with lower peritoneal membrane solutetransport characteristics.Automated peritoneal dialysis (APD) is a method There is yet another method, which I call a combina-where exchanges are performed mostly without active tion PD because it is neither exclusively nocturnal norparticipation of a person but by a pre-set peritoneal continuous. In this method, nocturnal exchanges aredialysis machine. APD is used in two kinds of prescrip- followed by one or two diurnal exchanges, but thetions: nightly peritoneal dialysis (NPD) and continuous peritoneal cavity is empty for part of the day.cyclic peritoneal dialysis (CCPD) [1,2].CCPD is a continuous, ambulatory regimen withan automated method for nightly exchanges, and a
The Separation of Powers, Court Curbing, and Judicial Legitimacy

AmajorfocusofjudicialpoliticsresearchhasbeentheextenttowhichideologicaldivergencebetweentheCourtandCongress can explain variation in Supreme Court decision making. However, conflicting theoretical and empirical findings have given rise to a significant discrepancy in the scholarship. Building on evidence from interviews with Supreme Court justices and former law clerks, I develop a formal model of judicial-congressional relations that incorporates judicial preferences for institutional legitimacy and the role of public opinion in congressional hostility towards the Supreme Court. An original dataset identifying all Court-curbing legislation proposed between 1877 and 2006 is then used to assess the influence of congressional hostility on the Court’s use of judicial review. The evidence indicates that public discontent with the Court, as mediated through congressional hostility, creates an incentive for the Court to exercise self-restraint. When Congress is hostile,theCourtusesjudicialreviewtoinvalidateActsofCongresslessfrequentlythanwhenCongressisnothostiletowards the Court. D uring each of the two recent Supreme Court confirmation hearings in the United States Senate, the Judiciary Committee noted its concern with what it perceived to be an overly aggressive Supreme Court and an imbalance in the separation of powers. Chairman Arlen Specter opened the confirmation hearings of John Roberts by commenting, “I’m very much concerned about what I conceive to be an imbalance in the separation-of-powers between the Congress and the court.IamconcernedaboutwhatIbluntlysayisthedenigration by the court of congressional authority.” 1 Senator Specter’s comments highlight a claim about American democracy which has been at the center of a lively academic debate for decades: the Supreme Court is an insulated legal body, free to make decisions away from the political pressures of Congress and the Executive. In this article, I challenge that claim. First, relying on evidence from interviews with Supreme Court justices and former law clerks, I establish a set of assumptions about judicial preferences that departs from previ
Prolonged intravenous hydrochloric acid infusion for severe metabolic alkalosis.

A 56-year-old man developed severe metabolic alkalosis in association with postoperative oliguric renal failure. Marked hypercapnia and metabolic alkalosis were successfully treated by a 17 day infusion of hydrochloric acid. Correction of metabolic alkalosis by intravenous HCL infusion, even as long term therapy, appears to be safe.