cssi/SciSciGPT-SciSciNet huggingface dataset:
The consequence of premature silicone stent loss after external dacryocystorhinostomy.

Purpose To investigate the clinical affects of premature silicone stent loss after external dacryocystorhinostomy (DCR). Design Retrospective chart review. Participants Two hundred thirty-three consecutive external dacryocystorhinostomies. Methods Demographic information was recorded, including length to follow-up, age, gender, number of days until stent removal, and success of surgery. All patients who extruded their silicone stent prematurely were identified. All were primary DCRs (i.e., all reoperations were excluded). All patients had had documented nasolacrimal duct obstruction before surgery, with or without current or prior dacryocystitis. Main Outcomes Measures Failure of DCR surgery was accepted as symptomatic epiphora with notable nasolacrimal duct blockage and/or infection at long term follow-up. Results Of the 233 DCRs, 42 stents extruded or had to be removed before the planned 2-month period. The overall success rate of the surgery was 94.9%, with a 90.5% success for those who had early extrusion and 95.8% for those who did not ( P = 0.24). Moreover, of the 4 people who had a failed surgery (of 42 early extrusions), none had a recurrent infection or pain, and only 1 opted to have a revision of the surgery. Patient age, gender, or timing of the extrusion was not found to affect surgical success significantly. Conclusions Our experience and this study suggest that concerns over early stent extrusion or removal may not be wholly warranted. Moreover, our review of the literature shows no evidence-based recommendations that longer stent retention or reintubation after early extrusion results in a higher success rate. Although other surgeries (e.g., canalicular laceration, congenital epiphora) may benefit from intervention or reinsertion after early extrusion, we cannot extrapolate such a practice for the DCR.
Possible Sources of Wage Divergence among Metropolitan Areas of the United States

Much of the literature on sub-national income convergence relates to states and regions. This paper focuses upon metropolitan areas as the germane geographical units for studying income convergence. Evidence of metropolitan wage divergence, the opposite of convergence, is presented. A theoretical basis for wage divergence is found in endogenous growth models and in two-sector trade models. Cross-section regression equations are estimated in which the level and the growth of metropolitan wages are related to variables that the empirical evidence and the theory suggest may be important sources of wage divergence.
Optical pulse storage loops

Optical fiber storage loops storing packets of high-speed optical return-to-zero data have been demonstrated. Storage times greater than 30 minutes have been achieved. A basic storage loop design, demonstrated at 20 Gb/s, resembles an active-passive harmonically mode-locked fiber laser. A new modulation technique, rational-harmonic modulation, has been used in a similar storage loop design to achieve 50 Gb/s storage, using a modulator with only a 13 GHz 3 dB bandwidth. A 10.6 Gb/s all-optical storage loop has also been demonstrated, in which the electro-optic modulator has been replaced with a semiconductor diode amplifier which is driven by an optical clock.
Surgical management of large tumors of the neck

Abstract Two cases of unusually large tumors of the neck are presented. The first tumor was a hyperfunctioning adenomatous goiter, which weighed 1,075 Gm. The second was an adenocarcinoma of the parotid gland of the mixed tumor type, which weighed 2,100 Gm. In the surgical management of large cervical tumors adequate exposure is essential. In removal of large goiters the trachea should be located in order to facilitate tracheotomy if that becomes necessary. If part of the goiter is intrathoracic, the superior pole of the thyroid and the superior thyroid vessels should be isolated, doubly ligated and divided before one attempts to elevate the intrathoracic portion. The dead space left by removal of the goiter should be drained with a strip of finely woven gauze. Mixed tumors of the parotid gland are almost invariably malignant histologically but rarely metastasize. In the removal of large parotid tumors avoidance of injury to the internal carotid artery is of prime importance. It is safer to ligate the common carotid artery than the internal carotid. The facial nerve should be preserved if possible. Postoperative radium therapy is advisable.
Joint space-time channel parameter estimation for DS-CDMA system in multipath Rayleigh fading channels

An approximate maximum likelihood method for joint estimation of time delays and directions-of-arrival for direct-sequence code-division multiple-access systems over multipath Rayleigh fading channels is presented. To reduce the computational complexity, the multi-dimensional maximisation problem is transformed into two simple one-dimensional maximisation problems using an iterative scheme. To illustrate the performance, simulation results are compared with Cramer-Rao bounds.
The nudel protease of Drosophila is required for eggshell biogenesis in addition to embryonic patterning.

The dorsoventral axis of the Drosophila embryo is defined by a ventral signal that arises within the perivitelline space, an extracellular compartment between the embryo plasma membrane and the vitelline membrane layer of the eggshell. Production of the ventral signal requires four members of the serine protease family, including a large modular protein with a protease domain encoded by the nudel gene. Here we provide evidence that the Nudel protease has an integral role in eggshell biogenesis. Mutations in nudel that disrupt Nudel protease function produce eggs having vitelline membranes that are abnormally permeable to the dye neutral red. Permeability varies among mutant nudel alleles but correlates with levels of Nudel protease catalytic activity and function in embryonic dorsoventral patterning. These mutations also block cross-linking of vitelline membrane proteins that normally occurs upon egg activation, just prior to fertilization. In addition, Nudel protease autoactivation temporally coincides with vitelline membrane cross-linking and can be triggered in mature eggs in vitro by conditions that lead to egg activation. We discuss how the Nudel protease might be involved in both eggshell biogenesis and embryonic patterning.
AN EMPIRICAL PROTOCOL FOR WHOLE‐CELL IMMUNOFLUORESCENCE OF MARINE PHYTOPLANKTON1

An immunofluorescence protocol for intracellular antigens of phytoplankton was developed empirically. Paraformaldehyde (4%) was used to fix samples for 6 h at 4° C; fixed samples can be stored in cold (–20°C) methanol for at least 1 month. We used Triton X-100, Nonidet P-40, and dimethyl sulfoxide to permeabilize the cells for antibody penetration across the cell wall and plasma membrane. After immunolabeling at room temperature, the samples were mounted on slides and could be stored at 4° C for up to 6 months without significant decay of the fluorescence. The staining was examined with an epifluorescence microscope; semiquantitative (percentage of cells with positive staining) and quantitative (staining intensity measured with an imaging system) analyses were performed. Reproducible staining was achieved for nuclear, chloroplastic, cytoplasmic, and cell surface antigens in species of Chlorophyceae, Prymnesiophyceae, Bacillariophyceae, and Dinophyceae including some field-collected samples. This protocol is advantageous to previously published protocols in that it allows relatively simple and long-term storage of fixed samples and allows staining of multiple antigens for the same sample. Although improvement on cell permeabilization is required for some species, the present protocol could prove useful for physiological or ecological studies when frequent sampling is required and immediate processing of the samples is not possible.
Macrophage differentiation increases expression of the ascorbate transporter (SVCT2).

Abstract To determine whether macrophage differentiation involves increased uptake of vitamin C, or ascorbic acid, we assessed the expression and function of its transporter SVCT2 during phorbol ester-induced differentiation of human-derived THP-1 monocytes. Induction of THP-1 monocyte differentiation by phorbol 12-myristate 13-acetate (PMA) markedly increased SVCT2 mRNA, protein, and function. When ascorbate was present during PMA-induced differentiation, the increase in SVCT2 protein expression was inhibited, but differentiation was enhanced. PMA-induced SVCT2 protein expression was blocked by inhibitors of protein kinase C (PKC), with most of the affect due to the PKCβI and βII isoforms. Activation of MEK/ERK was sustained up to 48 h after PMA treatment, and the inhibitors completely blocked PMA-stimulated SVCT2 protein expression, indicating an exclusive role for the classical MAP kinase pathway. However, inhibitors of NF-κB activation, NADPH oxidase inhibitors, and several antioxidants also partially prevented SVCT2 induction, suggesting diverse distal routes for control of SVCT2 transcription. Both known promoters for the SVCT2 were involved in these effects. In conclusion, PMA-induced monocyte–macrophage differentiation is enhanced by ascorbate and associated with increased expression and function of the SVCT2 protein through a pathway involving sustained activation of PKCβI/II, MAP kinase, NADPH oxidase, and NF-κB.
Assessment of expert-novice chemistry problem solving using HyperCard: Early findings

Results of a HyperCard method for assessing the performance of expert and novice high school chemistry students solving stoichiometric chemistry problems (balancing chemical equations) have been reported. The assessment involved the use of a HyperCard instrument (“Hyperequation”) developed on a Macintosh platform to administer a set of five chemistry problems, register student responses, and collect data related to student performance. The chemistry problems have been previously tested and validated in traditional (pen-paper) assessment settings by other researchers. MANOVA results indicate a significant difference between the performance of expert and novice students solving the five stoichiometric chemistry problems using the Hyperequation. The study shows promise in that a HyperCard assessment method could differentiate between the performance of experts and novices in problem solving. The implication is that HyperCard might be a suitable technology for developing performance assessment methods not only in chemistry but also in other science disciplines.
Cloning and characterization of a cDNA encoding rat PKR, the double-stranded RNA-dependent eukaryotic initiation factor-2 kinase☆

Abstract We have isolated and sequenced a full-length cDNA encoding the double-stranded RNA-dependent protein kinase PKR from rat. The derived amino acid sequences of the protein kinase and RNA-binding domains are highly conserved between the rat, human and mouse enzymes. In addition, sequence elements in the 5′- and 3′-untranslated regions are also conserved between species.
Exploring the early origins of the synapse by comparative genomics

One set of evolutionary features that has received less attention than the evolution of genes or species is the evolution of cellular machines, the self-contained structures in cells with dedicated functions. Here I suggest that domain expansion through shuffling, duplication, and changes in protein expression level are critical drivers in the evolution of cellular machines. Once established, evolutionary change in these cellular machines tends to occur by paralogy or expansion and modification of the existing core genes. A comparative genomics approach to one cellular machine—the post-synaptic complex—provided preliminary validation of these views. A comparative genomics approach to the entire cellulome may reveal the diversity of cellular machines and their inter-relationships.
Delay-Throughput Trade-Off with Opportunistic Relaying in Wireless Networks

In this paper, we study the delay/throughput trade-off with opportunistic relaying over channels with random connections, in which the channel connections are independent and identically distributed (i.i.d.). Previous work~\cite{CA:07} which proposed an opportunistic relaying scheme has focused on the throughput analysis only, we show that the opportunistic relaying scheme provides an upper bound of $O(n)$ delay, including full effects of queueing in the network model. In addition, we use the redundant scheduling algorithm to reduce the upper bound of delay scaling to $O(n/\sqrt{\log n})$. Furthermore, we prove two key inequalities that capture the various tradeoffs inherent in the broad class of opportunistic relaying protocols, which indicate the tradeoff of $delay/throughput \geq O(n/\log n)$, illustrating that no scheduling and routing algorithm can simultaneously yield lower delay and higher throughput.
Running many molecular dynamics simulations on many supercomputers

The challenges facing biomolecular simulations are many-fold. In addition to long time simulations of a single large system, an important challenge is the ability to run a large number of identical copies (ensembles) of the same system. Ensemble-based simulations are important for effective sampling. Due to the low-level of coupling between them, ensemble-based simulations are good candidates to utilize distributed cyberinfrastructure. The problem for the practitioner is thus effectively marshaling thousands if not millions of high-performance simulations on distributed cyberinfrastructure. Here we assess the ability of an interoperable and extensible pilot-job tool (BigJob), to support high-throughput simulations of high-performance molecular dynamics simulations across distributed supercomputing infrastructure. BigJob provides the capability to run hundreds or thousands of MPI ensembles concurrently. This is advantageous on large machines because it reduces the number of submissions to the queue, thereby reducing the overall waiting time in the queue. The wait time problem is further complicated by scheduling policies on some large XSEDE machines that prioritize large job requests over very small or single core job requests. Using a nucleosome positioning problem as an exemplar, we demonstrate how we have addressed this challenge on the TeraGrid/XSEDE. Specifically, we compute 336 independent trajectories of 20 ns each. Each trajectory is divided into twenty 1 ns long simulation tasks. A single task requires a 42 MB of input, 9 hours of compute time on 32 cores, and generates 3.8 GB of data. In total we have 6,720 tasks (6.7 μs) and approximately 25 TB to manage. There is natural task-level concurrency, as these 6,720 tasks can be executed with 336-way task concurrency. This project requires approximately 2 million hours of CPU time and could be completed in just over 1 month on a dedicated supercomputer containing 3,000 cores. In practice, even such a modest supercomputer is a shared resource and our experience suggests that a simple scheme to automatically batch queue the tasks, might require several years to complete the project. In order to reduce the total time-to-completion, we need to scale-up, out and across various resources. Our approach is to aggregate many ensemble members into pilot-jobs, distribute pilot-jobs over multiple compute resources concurrently, and dynamically assign tasks across the available resources. Here we report the computational methodology employed in our study and refrain from analyzing the biological aspects of the simulations.
Japan's First Cyborg? Miss Nippon, Eugenics and Wartime Technologies of Beauty, Body and Blood:

In June 1931, on the eve of the invasion of Manchuria, the Japanese mass media announced the winner of the first Miss Nippon contest. Applicants were limited to rank amateurs whose photographs, and not bodies, were judged by a panel of mostly elderly men who regarded the contest as `culture work'. A second contest was held in 1934. One of the main objectives of the Miss Nippon contests was to locate and record photographically, young women whose allegedly `pure blood' and ideal bodily proportions demonstrated the success of eugenics and social hygiene programs launched decades earlier. Japan's imperialist aggression in Asia and the Pacific forms the backdrop to this study on the centrality of popular cultural events and media in the state's attempt to improve the `Japanese race' through technologies of eugenics and social hygiene. The article explores the politics of blood, body and beauty, three interrelated subjects, framed by the Miss Nippon contests, that were common to the colonial project and the di...
Comparison of 68Ga-EDTA, [l-11C]α-aminoisobutyric acid, and [99mTC]sodium pertechnetate in an experimental blood-brain barrier lesion

Abstract Unilateral opening of the blood-brain barrier (BBB) in rats, induced by infusion of a hyperosmotic solution of mannitol into the left internal carotid artery, was applied to compare 68 Ga-EDTA, [1- 11 C]α-aminoisobutyric acid (using the long-lived 14 C-labeled analog), and [ 99m Tc]sodium pertechnetate as agents for diagnosis of BBB disruption. Of the three agents and two time intervals studied, 68 Ga-EDTA at 30 min postinjection gave the highest target-to-nontarget ratio. In addition, 68 Ga-EDTA, unlike commonly used 99m Tc)sodium pertechnetate, can be used in conjunction with positron emission tomography, which could make possible earlier and better assessment of BBB defects using 68 Ga-EDTA.
Variations in Common Carotid Artery Intima-Media Thickness during the Cardiac Cycle: Implications for Cardiovascular Risk Assessment

Background Common carotid artery intima-media thickness (IMT), a measure of atherosclerosis, varies between peak systole and end-diastole. This difference might affect cardiovascular risk assessment. Methods IMT measurements of the right and left common carotid arteries were synchronized with an electrocardiogram, using the R wave for end-diastole and the T wave for peak systole. IMT was measured in 2,930 members of the Framingham Offspring Study. Multivariate regression models were generated with end-diastolic IMT, peak systolic IMT, and change in IMT as dependent variables and Framingham risk factors as independent variables. End-diastolic IMT estimates were compared with the upper quartile of IMT on the basis of normative data obtained at peak systole. Results The average age of the study population was 57.9 years. The average difference in IMT during the cardiac cycle was 0.037 mm (95% confidence interval, 0.035–0.038 mm). End-diastolic IMT and peak systolic IMT had similar associations with Framingham risk factors (total R 2 = 0.292 vs 0.275) and were significantly associated with all risk factors. In a fully adjusted multivariate model, thinner IMT at peak systole was associated with pulse pressure ( P P = .0064), age ( P = .046), and no other risk factors. Performing end-diastolic IMT measurements while using upper quartile peak systolic IMT normative data led to inappropriately increasing by 42.1% the number of individuals in the fourth IMT quartile (high cardiovascular risk category). Conclusion The difference in IMT between peak systole and end diastole is associated with pulse pressure, low-density lipoprotein cholesterol, and age. In this study, the mean IMT difference during the cardiac cycle led to an overestimation by 42.1% of individuals at high risk for cardiovascular disease.
Novel Biomimetic Scaffold for Tendon/Ligament Tissue Engineering

An emerging approach to repair and replace a great number of the ligament and tendon injuries that occur each year is the use of tissue engineering principles to fabricate replacement tissues. One of the current challenges in tendon/ligament tissue engineering is fabricating scaffolds that possess both the proper mechanical and biological properties. A promising strategy to produce such scaffolds is electrospinning. Electrospinning uses a high-voltage power supply to draw viscous polymer solutions into ultra-fine fibers with nanometer-scale diameters, thus structurally mimicking native extracellular matrix components, such as collagen fibrils. Nano-scale fibers have been previously shown to enhance cellular proliferation, as well as stimulate cells to maintain morphology and phenotype when compared to scaffolds composed of larger fibers [1]. Furthermore, electrospinning provides researchers the flexibility of fabricating aligned scaffolds with isotropic mechanical properties to mimic native tissue mechanics [2]. However, scaffolds composed of aligned electrospun nanofibers often do not possess the elasticity and tensile strength required to properly carry out the mechanical function of tendon/ligament tissues. One approach that has been used to enhance mechanical properties of fibrous scaffolds is to weave multiple fibrous bundles into a braided scaffold. [3]. In this study, we fabricated a novel tendon/ligament tissue engineering scaffold that combines enhanced biological properties of electrospun scaffolds with enhanced mechanical properties through braiding. Furthermore, our approach offers the versatility to tailor tensile strength and elasticity of the braided scaffolds simply by varying the pattern of braiding, making it possible for researchers to construct tendon/ligament scaffolds with various mechanical properties.© 2010 ASME
DOMINANT CHROMOSOMAL MUTATION BYPASSING CHROMOSOMAL GENES NEEDED FOR KILLER RNA PLASMID REPLICATION IN YEAST

Yeast strains carrying a double-stranded RNA plasmid of 1.4-1.7 x 10(6) daltons encapsulated in virus-like particles secrete a toxin that kills strains lacking this plasmid. The plasmid requires at least 24 chromosomal genes (pets, and mak1 through mak23) for its replication or maintenance. We have detected dominant Mendelian mutations (called KRB1 for killer replication bypass) that bypass two chromosomal genes, mak7 and pets, normally needed for plasmid replication. Strains mutant in mak7 and carrying the bypass mutation (mak7-1 KRB1) are isolated as frequent K(+)R(+) sectors of predominantly K(-)R( -) segregants from crosses of mak7-1 with a wild-type killer. All KRB1 mutations isolated in this way are inherited as single dominant centromere-linked chromosomal changes. They define a new centromere. KRB1 is not a translational suppressor. KRB1 strains contain a genetically normal killer plasmid and ds RNA species approximately the same in size and amount as do wild-type killers. Bypass of both mak7 and pets by one mutation suggests that these two genes are functionally related. Two properties of the inheritance of KRB1 indicate an unusually high reversion frequency: (1) Heat or cycloheximide (treatments known to cure strains of the wild-type killer plasmid) readily induce conversion of mak7-1 KRB1 strains from killers to nonkillers with concomitant disappearance of KRB1 as judged by further crosses, and (2) mating two strains of the type mak7-1 KRB1 with each other yields mostly 2 K(+)R(+): 2 K(-)R(-) segregation, although the same KRB1 mutation and the same killer plasmid are present in both parents.
Accounting Policy And Carbon Credits

In 1996 the Kyoto Protocol established a global policy aimed at reducing green house gas (GHG) emissions. In response, slow steady steps are being taken to implement carbon emission limits. Markets are being established so that companies can exchange carbon allowances. Turning the environment, a public good, into private property presents many economic challenges. This paper explores the implications of the policy direction established in the Kyoto accord. Several changes to corporate accounting policy are recommended. The anticipated benefit is that socially responsible professionals will prepare their institutions cost and financial accounting systems to encourage success as carbon emissions become more regulated.
Reassessing Madison's Diversity Hypothesis: The Case of Same-Sex Marriage

Scholars have long suggested that population diversity should serve as a check on majority tyranny, but empirical evidence for this diversity hypothesis is inconclusive. This essay suggests that mixed findings arise because of the way in which scholars have translated Madisonian writings into statistical tests. It argues that the Federalist papers actually suggest an interactive relationship, where diversity moderates the effectiveness of representative institutions in protecting minority rights, rather than a direct relationship between population homogeneity and repression. The article tests for this moderating effect via a mixed methods approach, which includes a quantitative analysis of the passage of same-sex marriage bans in the American states, as well as a qualitative examination of legislative activity in four states.
The effect of therapeutic hypothermia on drug metabolism and response: cellular mechanisms to organ function.

Introduction: Therapeutic hypothermia is being employed clinically due to its neuro-protective benefits. Both critical illness and therapeutic hypothermia significantly affect drug disposition, potentially contributing to drug–therapy and drug–disease interactions. Currently, there is limited information on the known alterations in drug concentration and response during mild hypothermia treatment, and there is a limited understanding of the specific mechanisms that underlie alterations in drug concentrations and the potential clinical importance of these changes. Areas covered: A systemic review of the effect of therapeutic hypothermia on drug metabolism, disposition and response is provided. Specifically, the clinical and preclinical evidence of the effects of therapeutic hypothermia on blood flow, specific hepatic metabolism pathways, transporter function, renal excretion, pharmacodynamics and the effects during rewarming are reviewed. Expert opinion: Available evidence demonstrates that mild hypothermi...
Self-Esteem, Autonomy, and Moral Behavior in College Men and Women

Summary Measures of self-esteem, autonomy, and moral behavior were administered to 50 male and 50 female college students. Significant correlations were obtained between self-esteem and autonomy, and between self-esteem and frequencies of good and bad behavior, but not between autonomy and moral behavior. Separate analyses for each sex indicated that self-esteem is a better predictor of moral behavior and attitude toward frequency of moral behavior for females than for males. An explanation based on the different socialization experiences of males and females is offered.
Breeding Potential of Elite Pee Dee Germplasm in Upland Cotton Breeding Programs

Successful plant breeding programs begin with parental line selection. Effective parental line selection is facilitated when the breeding potential of candidate parental lines is known. Using topcross families involving germplasm from eight U.S. public cotton (Gossypium hirsutum L.) breeding programs, we evaluated the breeding potential of recently developed, elite Pee Dee germplasm. Based on parental line mean performance, hybrid performance, and genetic effect estimates, the breeding potential for recently developed, elite Pee Dee germplasm was similar to or better than the breeding potential of two well-known, commercial cultivars. Results suggest that crosses involving germplasm from the USDAARS, Stoneville, MS, and USDA-ARS, Maricopa, AZ, cotton germplasm enhancement programs offer high fi ber quality potential. In addition, our results suggest that recently developed, elite Pee Dee germplasm can be used to generate offspring with a lessened or absent negative relationship between agronomic performance and fi ber quality. Cotton breeders can use the information provided herein to facilitate their efforts to develop elite breeding lines, recurrent parents, and/or commercial cultivars.
Real-Time System Identification of a Small Multi-Engine Aircraft

In-flight identification of an aircraft’s dynamic model can benefit adaptive control schemes by providing estimates of aerodynamic stability derivatives in real time. This information is useful when the dynamic model changes severely in flight such as when faults and failures occur. Moreover a continuously updating model of the aircraft dynamics can be used to monitor the performance of onboard controllers. Flight test data was collected using a sum of sines input implemented in closed loop on a twin engine, fixed wing, Unmanned Aerial Vehicle. This data has been used to estimate a complete six degree of freedom aircraft linear model using the recursive Fourier Transform Regression method in frequency domain. The methods presented in this paper have been successfully validated using computer simulation and real flight data. This paper shows the feasibility of using the frequency domain Fourier Transform Regression method for real time parameter identification.
Some Ethical Implications for Capitalism of the Socialist Calculation Debate

The debate that raged in the interwar period between the Austrian economists (who argued the thesis that under socialism it would not be possible to engage in rational economic calculation) and socialist economists (who rejected that thesis) was, narrowly conceived, a debate in positive economics. What was being discussed was certainly not the morality of capitalism or of socialism. Nor, strictly speaking, was the debate even about society's economic well-being under socialism; it concerned the ability of central planners to make decisions that take appropriate account of relevant resource scarcities, in the light of consumer preference rankings. To be sure, the extraordinary interest which surrounded the debate and the passions that lurked barely below its surface testified to the powerful implications of the debate for crucial issues in welfare economics. The Austrians were not merely exploring the economies of socialism; they were in effect demonstrating that, as an economic system attempting to serve the needs of its citizens, socialism must inevitably fail. But, even if the debate is interpreted in its broadest terms, as a debate in welfare economics, it represented a sharp break widi traditional polemics relating to the socialism-capitalism issue. Traditionally the arguments for or against capitalism had, until 1920, been deeply involved in ediical questions. Mises's 1920 challenge to socialism, in contrast, was explicit in making no attempt to address any claims concerning the alleged moral superiority of socialism. He simply argued that, as an economic system, socialism was inherendy incapable of fulfilling the objectives of its proponents; central planners are unable to plan centrally.
Multiculturalism: A Redefinition of Citizenship and Community.

In this article, the author maintains that urban public schools' multicultural curriculum either bridges or fragments students' racial and ethnic differences. The author also argues that racial and...
A study for stainless steel fan blade design with metal foam core

The pursuit for cheap, low-density and high-performance materials in the design of aircraft engine blades raises wide-ranging challenges to the materials and structural design engineers. Traditionally, these components have been fabricated using expensive materials such as lightweight titanium alloys and polymer composite materials composites. The present study investigates the use of a sandwich foam fan blade made of solid face sheets and a metal foam core. The face sheets and the metal foam core material were an aerospace grade precipitation-hardened 17-4 stainless steel with high strength and high toughness. The stiffness of the sandwich structure is increased by separating the two face sheets by a foam core. The resulting structure possesses a high stiffness while being lighter than a similar solid construction. Since the face sheets carry the applied bending loads, the sandwich architecture is a viable engineering concept. The material properties of 17-4 precipitation-hardened metal foam are briefly ...
Clinical registries and quality measurement in surgery: a systematic review.

Background Surgical clinical registries provide clinical information with the intent of measuring and improving quality. This study aimed to describe how surgical clinical registries have been used to measure surgical quality, the reported findings, and the limitations of registry measurements. Methods Medline, CINAHL, and Cochrane were queried for English articles with the terms: “registry AND surgery AND quality.” Eligibility criteria were studies explicitly assessing quality measurement with registries as the primary data source. Studies were abstracted to identify registries, define registry structure, uses for quality measurement, and limitations of the measurements used. Results A total of 111 studies of 18 registries were identified for data abstraction. Two registries were financed privately, and 5 registries were financed by a governmental organization. Across registries, the most common uses of process measures were for monitoring providers and as platforms for quality improvement initiatives. The most common uses of outcome measures were to improve quality modeling and to identify preoperative risk factors for poor outcomes. Eight studies noted improvements in risk-adjusted mortality with registry participation; one found no change. A major limitation is bias from context and means of data collection threatening internal validity of registry quality measurement. Conversely, the other major limitation is the cost of participation, which threatens the external validity of registry quality measurement. Conclusion Clinical registries have advanced surgical quality definition, measurement, and modeling as well as having served as platforms for local initiatives for quality improvement. The implication of this finding is that subsidizing registry participation may improve data validity as well as engage providers in quality improvement.
Sensitivity of Volume-regulated Anion Current to Cholesterol Structural Analogues

Depletion of membrane cholesterol and substitution of endogenous cholesterol with its structural analogues was used to analyze the mechanism by which cholesterol regulates volume-regulated anion current (VRAC) in endothelial cells. Depletion of membrane cholesterol enhanced the development of VRAC activated in a swelling-independent way by dialyzing the cells either with GTPγS or with low ionic strength solution. Using MβCD–sterol complexes, 50–80% of endogenous cholesterol was substituted with a specific analogue, as verified by gas-liquid chromatography. The effects of cholesterol depletion were reversed by the substitution of endogenous cholesterol with its chiral analogue, epicholesterol, or with a plant sterol, β-sitosterol, two analogues that mimic the effect of cholesterol on the physical properties of the membrane bilayer. Alternatively, when cholesterol was substituted with coprostanol that has only minimal effect on the membrane physical properties it resulted in VRAC enhancement, similar to cholesterol depletion. In summary, our data show that these channels do not discriminate between the two chiral analogues of cholesterol, as well as between the two cholesterols and β-sitosterol, but discriminate between cholesterol and coprostanol. These observations suggest that endothelial VRAC is regulated by the physical properties of the membrane.
Measuring Word of Mouth's Impact on Theatrical Movie Admissions

Information transmission among consumers (i.e., word of mouth) has received little empirical examination. I offer a technique that can identify and measure the impact of word of mouth, and apply it to data from U.S. theatrical movie admissions. While variables and movie fixed effects comprise the bulk of observed variation, the variance attributable to word of mouth is statistically significant. Results indicate approximately 10% of the variation in consumer expectations of movies can be directly or indirectly attributed to information transmission. Information appears to affect consumer behavior quickly, with the length of a movie’s run mattering more than the number of prior admissions. Despite its widespread theoretical implications in environments of incomplete information, information transmission among consumers (a.k.a. word of mouth) has received relatively little empirical support. In this paper, I show that an existing method of detecting word of mouth is overly broad, in that its empirical prediction of autocorrelated growth can also be generated by a simple model of saturation in demand. I instead offer a model of demand that can accommodate both saturation and word of mouth, and then consider its implications within an error components framework. Applying this technique to U.S. theatrical admissions, my estimates suggest that word of mouth is statistically and economically significant and that information travels quickly to the average consumer in commonly observed situations. Simulations using these estimates confirm that word-of-mouth can have large impacts on how movies play out in theaters. I thank the editor and two anonymous referees for comments on an earlier draft that greatly improved the paper. Seminar participants at Washington University in St. Louis and the DeSantis Center’s Business and Economics Scholars Workshop also provided helpful feedback. The usual caveat applies. C
Effect of prenatal cocaine on early postnatal thermoregulation and ultrasonic vocalization production

Prenatal cocaine exposure can alter the postnatal care received by rat pups. Such effects could be caused in part by alterations in pup-produced stimuli that elicit early postnatal maternal care. Pup ultrasonic vocalizations are thought to be a particularly salient stimulus, and when paired with other cues, may elicit maternal attention. Cocaine is known to acutely alter thermoregulatory and cardiac function, thus prenatal cocaine may affect vocalizations through altering these functions. The data presented here determine the impact of full term prenatal cocaine exposure , saline exposure, or no exposure on thermogenic capacity, cardiac function, and the resulting ultrasonic vocalizations across the early postnatal period (days 1-5). Results indicated that while sharing many similar characteristics with saline-exposed and untreated animals, prenatal cocaine exposure was associated with specific alterations in vocalization characteristics on postnatal day 1 (PND 1), including call amplitude. Furthermore, numerous spectral parameters of their vocalizations were found altered on PND 3, including rate, call duration, and frequency, while no alterations were found on PND 5. Additionally, cocaine-exposed pups also showed a reduced thermoregulatory capacity compared to saline animals and reduced cardiac mass compared to untreated animals on PND 5. Together, these findings indicate that prenatal cocaine may be altering the elicitation of maternal care through its impact on vocalizations and thermoregulation, and suggests a potential mechanism for these effects through cocaine’s impact on developing stress systems.
Bidirectional trophic linkages couple canopy and understorey food webs

Summary 1. Cross-system resource flux is a fundamental component of ecological systems. Allochthonous material flows generate trophic linkages between adjacent food webs, thereby affecting community structure and stability in recipient systems. 2. We investigated cross-habitat trophic linkages between canopy and understorey food webs in a terrestrial, wooded, ecosystem in South Florida, USA. The focal community consisted of three species of Anolis lizards and their prey. We described interspecific differences among Anolis species in the strength and routing of these cross-habitat flows using stable isotope analysis, stomach content analysis and habitat use data. 3. All three Anolis species in this study consumed different prey and occupied vertically distinct arboreal habitats. Despite these differences, carbon isotope and stomach content analysis revealed strong integration with understorey and canopy food webs for all Anolis species. Modes of resource flux contributing to the observed cross-habitat trophic linkages included prey movement and the gravity-driven transport of detritus. 4. Our study shows that terrestrial systems are linked by considerable bidirectional cross-system resource flux. Our results also suggest that considering species-specific interactions between predator and prey is necessary to fully understand the diversity of material and energy flows between spatially separated habitats.
A portable graphical representation tool for phonocardiograms

This paper describes a prototype software application to display graphical and editable representations of patient data for use in electronic medical records (EMRs). The application dynamically generates graphics of cardiac and other patient data, and displays or saves them both in graphic and in text formats. The presentation of heart and other data in a consistent, clinically familiar, graphical format is designed to reduce the time necessary for anyone to review and understand this important information. Results of preliminary testing on actual case data are encouraging.
A decade of experience with dorsalis pedis artery bypass: analysis of outcome in more than 1000 cases.

Abstract Objective: The purpose of this study was to review our experience over the last decade with the dorsalis pedis bypass for ischemic limb salvage in patients with diabetes mellitus. Methods: The study was a retrospective analysis of a computerized vascular registry and chart review. From January 10, 1990 to January 11, 2000, 1032 bypasses to the dorsalis pedis artery were performed in 865 patients (27.6% of the 3731 lower extremity arterial bypass procedures performed in that time period). Five hundred ninety-seven patients (69%) were male, with a mean age of 66.8 years. Ninety-two percent had diabetes mellitus. All procedures were done for limb salvage. Conduits included 317 nonreversed saphenous vein (30.7%), 273 in situ (26.4%), 235 reversed vein (22.8%), 170 arm vein (16.5%), 35 other vein (3.4%), and two polytetrafluoroethylene (0.2%) grafts. The inflow arteries were as follows: 294 common femoral (28.5%), 550 popliteal (53.2%), 114 superficial femoral (11%), and 74 other (7.2%). Results: The mortality rate within 1 month of surgery was 0.9%, and 42 grafts (4.2%) failed in the same interval, although 13 were successfully revised. In a follow-up period that ranged from 1 to 120 months (mean, 23.6 months), primary patency, secondary patency, limb salvage, and patient survival rates were 56.8%, 62.7%, 78.2%, and 48.6%, respectively at 5 years and 37.7%, 41.7%, 57.7%, and 23.8% at 10 years. Both polytetrafluoroethylene grafts failed in less than 1 year. Primary graft patency was worse in female patients (46.5% female versus 61.6% male at 5 years; P P P Conclusion: Dorsalis pedis bypass is durable with a high likelihood of ischemic foot salvage over many years. Saphenous vein is the preferred conduit when available. Short vein grafts from distal inflow sites are possible in more than 50% of cases. These results justify the routine use of pedal arterial reconstruction for patients with diabetes with ischemic foot complications. (J Vasc Surg 2003;37:307-15.)
Erythrocyte adducin: a calmodulin-regulated actin-bundling protein that stimulates spectrin-actin binding

Adducin is an erythrocyte membrane skeletal phosphoprotein comprised of two related subunits of 105,000 and 100,000 Mr. These peptides form a functional heterodimer, and the smaller of the two binds calmodulin in a calcium-dependent fashion. Although this protein has been physicochemically characterized, its function remains unknown. We have examined the interaction of human adducin with actin and with human erythrocyte spectrin using sedimentation, electrophoretic, and morphologic techniques. Purified adducin binds actin at physiologic ionic strength and bundles it into arrays of laterally arranged filaments, the adducin forming cross-bridges between the filaments at 35.2 /- 3.8 (2 SD) nm intervals. The stoichiometry of high affinity adducin binding to actin at saturation is 1:7, corresponding to a dimer of adducin for every actin helical unit. Adducin also promotes the binding of spectrin to actin independently of protein 4.1. At saturation, each adducin promotes the association of one spectrin heterodimer. The formation of this ternary spectrin-actin-adducin complex is independent of the assembly path, and the complex exists in a readily reversible equilibrium with the free components. The binding of adducin to actin and its ability to stimulate spectrin-actin binding is down-regulated by calmodulin in a calcium-dependent fashion. These results thus identify a putative role for adducin, and define a calcium- and calmodulin-dependent mechanism whereby higher states of actin association and its interaction with spectrin in the erythrocyte may be controlled.
Electromigration and associated void formation in silver

Abstract Electromigration in both 99.999 per cent pure silver with about 1 ppm oxygen and 99.99 per cent pure silver with about 40 ppm oxygen (presumably in the form of impurity oxides) has been measured using the vacancy flux method. The method consists of determining local volume changes in specimens subjected to a large d.c. current density ( ∼ 10 4 A cm 2 ) and a parabolic temperature distribution, which results from water-cooling the specimen ends. As a result of improved temperature determination, the effective charge for electromigration was found to be about −6.5 e in contrast to the earlier reported value of about −25 e. Microscopic void formation on the cathode side and consequent sample elongation were observed only in the less pure silver and could not be induced in the purer material even when charged individually with oxygen or hydrogen. Some evidence indicated oxygen electromigration to the anode in silver and also an enhancement of the self-electromigration of the latter in the presence of dissolved hydrogen.
Ex vivo generation of genetically modified dendritic cells for immunotherapy: implications of lymphocyte contamination

Genetically modified dendritic cell (DC) vaccines expressing tumor-associated antigens are currently used for cancer immunotherapy. Peripheral blood (PB) monocyte precursors are a relatively convenient source of DCs for use in clinical studies, but are often contaminated by lymphocytes. The current study was conducted to examine the impact of T-lymphocyte contamination on genetically modified DC product. PB monocyte-derived DCs were efficiently transduced (75-95%) with an HIV-1-based self-inactivating lentiviral vector encoding a model antigen, the enhanced green fluorescent protein (eGFP). The lymphocyte-free DC culture transduced with Lenti-eGFP showed stable expression of eGFP without measurable decline in viability. In contrast, the eGFP-positive DCs disappeared rapidly in transduced DC cultures containing lymphocyte contaminants, concurrent with detectable activation and expansion of T-lymphocytes. Upon antigen recall, these T cells elicited major histocompatability complex-restricted antigen-specific cytotoxicity against eGFP-positive autologous DCs and mitogen-stimulated T lymphoblasts, mainly through the perforin-mediated pathway. In summary, this study demonstrate that the relative purity of DC cultures could determine the persistence of gene-modified DC, which may affect the induction of effective immune responses by DC vaccination strategies.
Inhibition of the chemokine (C–C motif) ligand 2/chemokine (C–C motif) receptor 2 pathway attenuates hyperglycaemia and inflammation in a mouse model of hepatic steatosis and lipoatrophy

Aims/hypothesis Using a mouse model of lipoatrophic diabetes, we hypothesised that the chemokine (C–C motif) ligand 2 (CCL2)/chemokine (C–C motif) receptor 2 (CCR2) pathway contributes to hepatic macrophage accumulation and insulin resistance through induction of a chronic inflammatory state.