cssi/SciSciGPT-SciSciNet huggingface dataset:
Machine Learning at all course levels

A relatively simple program, for example one which plays a trivial game, can be used to lead meaningful discussions about computer learning and thinking at a variety of undergraduate levels. In particular showing how simple machines "learn" introduces students to artificial intelligence. In addition to being fun, this approach provokes thought and discussion among the students. More importantly, the students continue to discuss and think about this topic months (even years!) after it is presented in class. Many Artificial Intelligence concepts are not beyond these students' abilities and they make early computer science courses more interesting. Finally the absence of clear answers to many of the questions challenges the students to think.
Fast and space-efficient location of heavy or dense segments in run-length encoded sequences

This paper considers several variations of an optimization problem with potential applications in such areas as biomolecular sequence analysis and image processing. Given a sequence of items, each with a weight and a length, the goal is to find a subsequence of consecutive items of optimal value, where value is either total weight or total weight divided by total length. There may also be a specified lower and/or upper bound on the acceptable length of subsequences. This paper shows that all the variations of the problem are solvable in linear time and space even with non-uniform item lengths and divisible items, implying that run-length encoded sequences can be handled in time and space linear in the number of runs. Furthermore, some problem variations can be solved in constant space. Also, these time and space bounds suffice for certain problem variations in which we call for reporting of many "good" subsequences.
Stratégies matrimoniales et émigration vers l’Amérique au XVIIIe siècle La maison Berrio de La Bastide Clairence

Prior to the massive wave of emigration to South America during the nineteenth century, inhabitants of rural communities in the western French Pyrenees emigrated in large numbers to Saint-Domingue and other Caribbean islands. This article examines the connections between migratory movements and the organization of these communities into “house societies” (Levi-Strauss) in which the continuation of the “house” was paramount and no new “houses” could be founded. Adopting a micro-historical approach, it analyzes the complex role of inheritance rights in the decision to emigrate and reconstructs the networks that made emigration possible. Unlike the traditional belief that sons were forced to leave because they were deprived of their share of inheritance, the family unit fully supported the emigration of its younger members. This article also argues that emigration simultaneously resulted from and undermined the “house system.”
Out of the Chattering Ice

A Brain for All Seasons Human Evolution and Abrupt Climate Change. William H. Calvin. University of Chicago Press, Chicago, 2002. 349 pp. $25, £16. ISBN 0-226-09201-1. Through the course of a travelogue, Calvin argues that repeated episodes of abrupt cooling played a critical role in human evolution and that human-caused global warming may paradoxically trigger another crash in global temperatures.
Crack-propagation theories.

Abstract : This article consists of two parts. In the first part, the crack propagation theories for brittle and quasi-brittle solids fracturing under a single application of the external loads are considered. The emphasis has been on the dynamic aspects of the fracture phenomenon and the related quantitative theories. Thus, the problem is discussed only from the viewpoint of continuum mechanics and classical thermodynamics. Two theoretical approaches are presented in detail. These are the dynamic crack propagation theory based on the concept of modulus of cohesion proposed by Barenblatt and various forms of the energy balance theory based essentially on the ideas proposed by Griffith. A detailed analysis of the energy balance around the periphery of the crack is given and it is shown that the energy available at the crack periphery to create new fracture surfaces is equivalent to the crack closure energy, which is different from the released strain energy if the inertia effects are not negligible. The results are applied to plane extensional and anti-plane shear problems. The techniques used in and the results obtained from the available experimental studies are then discussed.
The mechanism of Zn2+ adsorption on calcite

The adsorption of Zn2+ on calcite (CaCO3(s)) was investigated from aqueous solutions in equilibrium with CaCO3(s) and undersaturated with respect to Zn5(OH)6(CO3)2(s)). Zinc adsorption occurred via exchange with Ca2+ in a surface-adsorbed layer on calcite. The validity of this exchange reaction was supported by adsorption isotherm and constant concentration experiments, where Ca2+(aq) was varied by systematically changing the pH and CO2(g). Greater adsorption of Zn2+ occurred at higher pH and CO2(g) levels, where Ca2+ activities were lowest. Sites available for Zn2+ sorption were less than 10% of Ca2+ sites on the calcite surface. Surface exchange of Zn2+ did not affect the solubility of calcite. Zinc sorption was apparently independent of surface charge, which suggested that the surface complex had covalent character. Desorption and isotopic exchange experiments indicated that the surface complex remained hydrated and labile as Zn2+ was rapidly exchangeable with Ca2+. Careful analysis of the adsorption data showed that Zn2+ and ZnOH+ were the sorbing species. The exchange reaction was generalized as a power exchange function: K = 0.62 = {(Ca2+)(Zn2+ + ZnOH+)}[ZnXCaX]1.69 Zinc adsorption on calcite was compared to and was consistent with that of Co2+, but Zn2+ was more strongly sorbed.
Electrochemical tuning of olivine-type lithium transition-metal phosphates as efficient water oxidation catalysts

The oxygen evolution reaction is of paramount importance in clean energy generation and storage. While the common approach in search of active, durable and cost-effective oxygen evolution catalysts involves the development of novel materials, it is equally important to tune the properties of existing materials so as to improve their catalytic performance. Here, we demonstrate the general efficacy of electrochemical lithium tuning in organic electrolyte on enhancing the oxygen evolution catalytic activity of olivine-type lithium transition metal phosphates, a widely-researched family of cathode materials in lithium ion batteries. By continuously extracting lithium ions out of lithium transition metal phosphates, the materials exhibited significantly enhanced water oxidation catalytic activity. Particularly, the electrochemically delithiated Li(Ni,Fe)PO4 nanoparticles anchored on reduced graphene oxide sheets afforded outstanding performance, generating a current density of 10 mA cm−2 at an overpotential of only 0.27 V for over 24 h without degradation in 0.1 M KOH, outperforming the commercial precious metal Ir catalysts.
A Solution to the Problem of Nonequilibrium Acid/Base Gas-Particle Transfer at Long Time Step

A stable numerical solution to the unsolved problem of nonequilibrium growth/evaporation at long time step of multiple dissociating acids (e.g., nitric acid, hydrochloric acid, carbonic acid, sulfuric acid, etc.) and a base (ammonia) is discussed. The solution eliminates most oscillatory behavior observed in previous solutions at long time step. The solution is applicable across the entire relative humidity range, both in the presence and absence of solids and among multiple aerosol size bins and distributions. It involves solving growth/evaporation of semivolatile acids with a dissolutional growth scheme at high liquid water content (LWC), semivolatile acids with a condensational growth scheme at low LWC, involatile acids with a condensation scheme at all LWCs, then equilibrating ammonia and pH simultaneously between gas and solution phases at all LWCs based on updated acid contents, and finally solving internal-aerosol composition, final pH, and LWC with an operator-split equilibrium calculation. The ne...
Characterization of p21Ras-mediated apoptosis induced by protein kinase C inhibition and application to human tumor cell lines.

Suppression of PKC activity can selectively induce apoptosis in cells expressing a constitutively activated p21Ras protein. We demonstrate that continued expression of p21Ras activity is required in PKC-mediated apoptosis because farnesyltransferase inhibitors abrogated the loss of viability in p21Ras-transformed cells occurring following PKC inhibition. Studies utilizing gene transfer or viral vectors demonstrate that transient expression of oncogenic p21Ras activity is sufficient for induction of apoptosis by PKC inhibition, whereas physiologic activation of p21Ras by growth factor is not sufficient to induce apoptosis. Mechanistically, the p21Ras-mediated apoptosis induced by PKC inhibition is dependent upon mitochondrial dysregulation, with a concurrent loss of mitochondrial membrane potential (ψm). Cyclosporine A, which prevented the loss of ψm, also inhibited HMG-induced DNA fragmentation in cells expressing an activated p21Ras. Induction of apoptosis by PKC inhibition in human tumors with oncogenic p21Ras mutations was demonstrated. Inhibition of PKC caused increased apoptosis in MIA-PaCa-2, a human pancreatic tumor line containing a mutated Ki–ras allele, when compared to HS766T, a human pancreatic tumor line with normal Ki–ras alleles. Furthermore, PKC inhibition induced apoptosis in HCT116, a human colorectal tumor line containing an oncogenic Ki–ras allele but not in a subline (Hke3) in which the mutated Ki–ras allele had been disrupted. The PKC inhibitor 1-O-hexadecyl-2-O-methyl-rac-glycerol (HMG), significantly reduced p21Ras-mediated tumor growth in vivo in a nude mouse MIA-PaCa-2 xenograft model. Collectively these studies suggest the therapeutic feasibility of targeting PKC activity in tumors expressing an activated p21Ras oncoprotein. J. Cell. Physiol. 198: 277–294, 2004. © 2003 Wiley-Liss, Inc.
Selecting Agricultural Best Management Practices for Water Conservation and Quality Improvements Using Atanassov’s Intuitionistic Fuzzy Sets

Improper agricultural practices can affect ground water through leaching, surface water through runoff, algae infestations, deforestation, and air quality through burning operations and ammonia emissions. These effects may be mitigated through the institution of best management practices. The utility of best management practices (BMPs) is recognized and being actively promoted by agricultural agencies; however, identifying a set of mandatory BMPs is inappropriate given variations between climactic, demographic and geographic regions as well as differences in farming practices. In this study, a multi-criteria decision making model based on Attanassov’s Intuitionistic Fuzzy Set (A-IFS) theory is introduced and its utility to rank agricultural best management practices is illustrated using a case-study from South Texas. Implementation of the A-IFS MCDM method to the South Texas region resulted in “irrigation scheduling” being ranked as the most preferred alternative, while “brush control/management” was the least preferred. The A-IFS MCDM approach was particularly suitable for prioritizing and ranking agricultural best management practices because decision makers often tend to have both likes and dislikes with regards to specific BMPs and for a given evaluation attribute. Not only does the A-IFS MCDM method provide a single composite score to rank the BMP alternatives, but the output of the A-IFS MCDM method also includes upper and lower bounds that help identify the uncertainties in the decision making process.
Transparent Façade Panel Typologies Based on Recyclable Polymer Materials

Buildings are large consumers of energy. In the United States of America; they constitute over 33% of the total annual energy consumption, produce 35% of the total carbon dioxide emissions and attribute 40% of landfill wastes. The building industry is also a large consumer of non-renewable materials and this trend has escalated dramatically over the past century. It is essential that we find ways to save on energy consumption through the use of solar energy, improved thermal insulation, and alternative efficient glazed facade systems. In this paper, we demonstrate how alternative typologies of transparent and translucent load-bearing facade systems based on biocomposite and recyclable materials, are structurally and thermally efficient at the same time they contribute towards reduced pollutant emissions and non-renewable material uses.Composite insulated panel systems are used extensively in the engineering and building industry, owing to their structural and thermal efficiency. However, these systems are generally opaque and offer little flexibility in building applications. As an alternative, we demonstrate how building products comprised of hybrid material typologie scan be made to perform efficiently as load-bearing facade systems that substitute for current glazing systems with adequate thermal and structural performance, which also possess good light transmission characteristics and integral shading capability. The materials are configured to work as composite panel systems made from a combination of biocomposite and recyclable polymer materials. These materials are environmentally sustainable, because they either originate from naturally grown renewable resources or are recyclable. Our research program includes the design and development of prototype panel systems; the evaluation of structural and thermal performance, together with their role in reducing energy consumption and pollution emission through life cycle analysis. The paper describes relevant applications and related current research activities, being carried out by the authors, under an EPA/NSF funded grant project, titled People, Prosperity and Planet, in relation to prototypical composite panel systems. Our current area of investigation relates totypologies that use thermoplastic polymers (as skin material) and biocomposites (as a core material). Our evaluations have demonstrated viable applications and improved performance compared to conventional single and double glazing systems in buildings. The paper also discusses the fundamentals of the research investigations and predicts good energy efficiency, making the product a sustainable alternative when used in building applications. The paper highlights areas of ongoing research and applications for hybrid composite facade systems, which will make the approach a viable option for the building industry, in the future.
Successful percutaneous retrieval of an intracardiac catheter fragment in an 800-g premature infant.

OBJECTIVE: To present the case report of a successful retrieval of an intracardiac catheter in an 800 - g premature infant.
Computer Optimization of Reverse Osmosis Processing of Soy Whey with Cellulose Acetate Modules

Synopsis In processing full-fat soy flour to an acid-precipitated lipid protein concentrate a byproduct whey fraction results which, because of its high biological oxygen demand, represents a serious disposal problem. Processing of food waste streams by reverse osmosis has received considerable attention because of its low theoretical energy requirement since no phase change is involved. In a previous study at this Center a mathematical model was developed for the diffusive transport of soy lipid protein concentrate whey across cellulose acetate membranes. In this study, pumping energy and power costs combined with membrane life and replacement costs were incorporated into the original model to provide a basis for optimization from an energy cost standpoint. Computer-simulated runs were compared with experimental pilot-plant runs, and the agreement between predicted and actual results was quite good. Water flux rates were in the range of 3 to 7 gal/ft 2 /day. Computer runs were used to optimize the processing of 100,000 gal/day of soy whey at 8000 ppm biological oxygen demand (BOD). Costs were at a minimum with a six-stage tapered flow primary reverse osmosis treatment over a porous cellulose acetate membrane, followed by a six-stage tapered flow reverse osmosis over a tighter membrane. BOD reduction was 94% at a cost of $5.45/1000 gal.
Partial volume simulation in software breast phantoms

A modification to our previous simulation of breast anatomy is proposed, in order to improve the quality of simulated projections generated using software breast phantoms. Anthropomorphic software breast phantoms have been used for quantitative validation of breast imaging systems. Previously, we developed a novel algorithm for breast anatomy simulation, which did not account for the partial volume (PV) of various tissues in a voxel; instead, each phantom voxel was assumed to contain single tissue type. As a result, phantom projection images displayed notable artifacts near the borders between regions of different materials, particularly at the skin-air boundary. These artifacts diminished the realism of phantom images. One solution is to simulate smaller voxels. Reducing voxel size, however, extends the phantom generation time and increases memory requirements. We achieved an improvement in image quality without reducing voxel size by the simulation of PV in voxels containing more than one simulated tissue type. The linear x-ray attenuation coefficient of each voxel is calculated by combining attenuation coefficients proportional to the voxel subvolumes occupied by the various tissues. A local planar approximation of the boundary surface is employed, and the skin volume in each voxel is computed by decomposition into simple geometric shapes. An efficient encoding scheme is proposed for the type and proportion of simulated tissues in each voxel. We illustrate the proposed methodology on phantom slices and simulated mammographic projections. Our results show that the PV simulation has improved image quality by reducing quantization artifacts.
Once-Daily, Extended-Release Formulations of Antimuscarinic Agents in the Treatment of Overactive Bladder: A Review

Overactive bladder (OAB) is a chronic condition that often requires long-term treatment to maintain control of symptoms. A range of therapeutic options are available; however, antimuscarinic agents form the mainstay of treatment. Of these agents, tolterodine and oxybutynin are the most widely used. It is well documented that the immediate-release (IR) formulations of these agents have equivalent efficacy in relieving OAB symptoms. However, tolterodine demonstrates a more favorable tolerability profile, particularly in terms of the frequency and severity of dry mouth. Due to the development of novel drug delivery systems, extended-release (ER) formulations of both oxybutynin and tolterodine are now available, permitting once-daily dosing. The convenience of once-daily dosing of antimuscarinic agents would be expected to improve patient compliance and further relieve the symptoms of OAB. Clinical studies with the ER formulations of tolterodine and oxybutynin demonstrate potential clinical advantages over their respective IR forms in terms of either efficacy or tolerability or both, although the therapeutic index of tolterodine ER appears to show a greater advantage over its IR counterpart compared with oxybutynin ER and its IR form. Importantly, the two ER agents have not been compared directly in a head-to-head clinical study. Overall, available clinical data suggest that the newly developed ER formulation of tolterodine represents a significant therapeutic advancement in the treatment of OAB.
Regulation of inositol phosphate levels by prostaglandins in cultured endometrial cells.

Stimulation of cultured rabbit endometrial cells by one of the rabbit endometrial cell culture proliferation factors, prostaglandin F/sub 2//sub ..cap alpha../ (PGF/sub 2//sub ..cap alpha../), resulted in a very rapid increase in the intracellular levels of (/sup 3/H)-inositol triphosphate (IP/sub 3/), (/sup 3/H)-inositol biphosphate (IP/sub 2/), and (/sup 3/H)-inositol monophosphate (IP/sub 1/) in cells prelabeled with (/sup 3/H)-inositol. These increases in inositol phosphate levels were detected in periods of stimulation as short as 30 seconds, reached a maximum by 1 1/2-2 min and declined to control levels by 6-10 min. The stimulation was dose-dependent with maximal increases observed near 10/sup -6/ M PGF/sub 2//sub ..cap alpha../. The cholinergic agent, carbachol, also led to time and dose-independent increases in IP/sub 3/. Lithium, cadmium, silver, copper, and zinc ions had no effect either on the breakdown of IP/sub 3/ or on the accumulation of IP/sub 1/. In contrast, vanadate at 10/sup -6/ or 10/sup -5/ M did lead to a decrease in the breakdown of IP/sub 1/ and a concomitant increase in IP/sub 1/, IP/sub 2/, and IP/sub 3/. PGF/sub 2//sub ..cap alpha../ was found previously to induce an increase in rabbit endometrial cell DNA synthesis which was inhibited by concomitant ormore » prior addition of prostaglandin E/sub 1/ (PGE/sub 1/). PGE/sub 1/, in a dose-dependent manner, was found to inhibit the observed IP/sub 3/ increase by PGF/sub 2//sub ..cap alpha../ at 1 1/2 min of stimulation. PGF/sub 2//sub ..cap alpha../ treated and control cultures did not differ in cAMP 3 or cGMP levels, cellular /sup 45/Ca uptake, nor cellular /sup 22/Na uptake. The authors propose that P/sub 3/ may be one of the intracellular messenger(s) synthesized following the treatment of rabbit endometrial cell cultures with the proliferation agent PGF/sub 2//sub ..cap alpha../ and that it may play a crucial role with cAMP in growth regulation.« less
Genetic Alterations in Psoriasis

The genetic basis of psoriasis has long been recognized, including the knowledge that family members of patients with psoriasis are at greater risk of developing the disease (Henselers and Christophers, 1995). Several lines of evidence suggest that genes regulating IL-12 and IL-23 may be important in its pathogenesis. Part of the rationale stems from observations indicating that patients with psoriasis and those with Crohn's disease share common features: patients with Crohn's disease are five times more likely than the general population to have psoriasis, and both diseases respond to anti-tumor necrosis factor-α therapy (Lee et al., 1990). A recent genome-wide association scan identified a highly significant association between Crohn's disease and a single-nucleotide polymorphism (SNP) in the coding region of the IL23R gene (Duerr et al., 2006), suggesting that this polymorphism might be present in patients with psoriasis. Additional studies from several diverse ethnic populations throughout the world have determined that psoriasis is associated with SNPs in IL-12 and IL-23 or their receptors (Capon et al., 2007; Cargill et al., 2007; Chang et al., 2007; Tsunemi et al., 2002).
Numerical methods for experimental design of large-scale linear ill-posed inverse problems

While an experimental design for well-posed inverse linear problems has been well studied, covering a vast range of well-established design criteria and optimization algorithms, its ill-posed counterpart is a rather new topic. The ill-posed nature of the problem entails the incorporation of regularization techniques. The consequent non-stochastic error introduced by regularization needs to be taken into account when choosing an experimental design criterion. We discuss different ways to define an optimal design that controls both an average total error of regularized estimates and a measure of the total cost of the design. We also introduce a numerical framework that efficiently implements such designs and natively allows for the solution of large-scale problems. To illustrate the possible applications of the methodology, we consider a borehole tomography example and a two-dimensional function recovery problem.
Renal Toxicity of Long-Term Therapy With Tenofovir in HIV-infected Patients

Data are sparse on long-term renal toxicity of tenofovir as measured by estimated glomerular filtration rate (eGFR) and progression to advanced stages of chronic kidney disease (CKD). The objective...
On methods for solving the oceanic equations of motion in generalized vertical coordinates

Abstract We note that there are essentially two methods of solving the hydrostatic primitive equations in general vertical coordinates: the quasi-Eulerian class of algorithms are typically used in quasi-stationary coordinates (e.g. height, pressure, or terrain following) coordinate systems; the quasi-Lagrangian class of algorithms are almost exclusively used in layered models and is the preferred paradigm in modern isopycnal models. These approaches are not easily juxtaposed. Thus, hybrid coordinate models that choose one method over the other may not necessarily obtain the particular qualities associated with the alternative method. We discuss the nature of the differences between the Lagrangian and Eulerian algorithms and suggest that each has its benefits. The arbitrary Lagrangian–Eulerian method (ALE) purports to address these differences but we find that it does not treat the vertical and horizontal dimensions symmetrically as is done in classical Eulerian models. This distinction is particularly evident with the non-hydrostatic equations, since there is explicitly no symmetry breaking in these equations. It appears that the Lagrangian algorithms can not be easily invoked in conjunction with the pressure method that is often used in non-hydrostatic models. We suggest that research is necessary to find a way to combine the two viewpoints if we are to develop models that are suitable for simulating the wide range of spatial and temporal scales that are important in the ocean.
The treatment of meningiomas in the region of the cavernous sinus

The diagnosis and treatment of meningiomas of the cavernous sinus remains a controversial part of skull base surgery practice. The most common presenting symptom headache is nonspecific. Visual loss and oculomotor disturbance are the next likely symptoms and signs. It is possible to achieve total tumor removal in about 50% of patients, but an increase in cranial nerve dysfunction occurs in nearly as many. Improvement of neurological function, except for vision, is unusual. Because of the risk of complicating cranial nerve dysfunction by surgery, focused radiation as an alternative treatment has been explored in a small number of patients. Unfortunately, volume reduction is only seen in about one-third, but risks do appear to be low and nearly 60% of patients recorded have improvement in preoperative cranial nerve deficits. With these indolent tumors, much longer follow-ups are required before the role of focused radiation can be assessed.
Collective Acceleration with Intense Electron Beams

Collective acceleration methods that employ an intense relativistic electron beam (IREB) are discussed. A brief history and a classification of collective acceleration methods are given. Methods examined include IREB injection into neutral gas; IREB injection into vacuum; plasma-filled IREB diodes; and vacuum-filled IREB diodes. Accelerating fields of order 106 V/cm have been observed experimentally. The collective acceleration processes for IREB injection into neutral gas and vacuum are discussed. It is noted that the collective acceleration processes for IREB diodes have not been elucidated yet. A summary of present collective ion acceleration research areas that involve IREB's is given.
The Excess of Negative Over Positive Mesons Produced by High Energy Photons

Mesons produced by the high energy photon beam from the University of California Radiation Laboratory 330 Mev synchrotron are found to show an excess of negatives over positives. (1) With a carbon target, observing mesons in the energy range 30-130 Mev at 90° to the photon beam, the ratio of negative to positive mesons is 1.7 ± 0.2 with no significant energy dependence.
δ-Crystallin mRNA in chick lens cells: mRNA accumulates during differential stimulation of δ-crystallin synthesis in cultured cells

Abstract Increasing specialization for δ-crystallin synthesis is a prominent feature of the differentiation of chick lens epithelial cells into lens fiber cells and can be studied in cultured embryonic lens epithelia. Quantitation of δ-crystallin mRNA by molecular hybridizaton to a [ 3 H]DNA complementary to δ-crystallin mRNA demonstrates that differentiation, both in ovo and in tissue culture, is associated with the accumulation of δ-crystallin mRNA. In the cultures, there is an overall stimulation of protein synthesis, including δ-crystallin mRNA during the first 5 hr in vitro . Between 5 and 24 hr in vitro there is a differential stimulation of δ-crystallin synthesis and an accumulation of δ-crystallin mRNA that can quantitatively account for this stimulation.
PREGNANCY LACTOGENS IN THE RAT CONCEPTUS: CIRCULATING LEVELS, DISTRIBUTION OF BINDING, AND EXPRESSION OF RECEPTOR mRNA

The roles of the pregnancy lactogens in the growth and development of the fetal rat are poorly understood. We measured the concentrations of placental lactogen II (rPL-II) in fetal rat serum and examined the distribution and mRNA expression of lactogenic receptors in embryonic and fetal tissues. The concentration of rPL-II in fetal serum (day 20 gestation) was 28.3 ± 0.8ng/ml (n = 6), = 1/10th that in maternal serum (398.3 ± 45.3 ng/ml). At physiological concentrations, rPL-II bound specifically to the fetal adrenal, kidney, intestine, liver and pancreas. rPL-1, expressed on days 10-12, bound to chorion and mesometrial decidua. The binding of rPL-1 & II were blocked by rat prolactin (PRL) but not by rat GH, suggesting a common PL/PRL receptor. Fetal tissues expressed four PRL receptor mRNA transcripts (12, 6.6, 4.2, 1.8 kb). The relative intensities with which fetal tissues bound rPL correlated with levels of the 4.2 and 1.8 kb transcripts. The observation that rPL-1 binds to chorion and decidua suggests a paracrine role for rPL-1 in the regulation of maternal decidual function. The demonstration that rPL-II circulates in fetal blood and binds to lactogenic receptors in fetal tissues implicates a role for the pregnancy lactogens in fetal development.
Variations in reconstruction after radical cystectomy.

BACKGROUND. Most urologists specializing in the management of patients with bladder cancer consider continent urinary diversion the reconstructive technique that affords the best quality of life after radical cystectomy. The authors sought to evaluate factors that predict reconstructive technique after radical cystectomy. METHODS. Using linked data from Medicare and the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) program, 3611 subjects were identified who underwent radical cystectomy for bladder cancer between 1992 and 2000. Multivariate logistic regression was used to identify factors independently associated with utilization of continent reconstruction after radical cystectomy, incorporating patient and provider variables. RESULTS. In multivariate analysis, the likelihood of continent diversion was inversely associated with older age (odds ratio [OR] ≤0.68, P ≤ .002), African American race (OR 0.43, P = .003), and higher comorbidity index (OR 0.71, P = .03), and directly associated with male sex (OR 1.45, P = .002), higher education level (OR 1.54, P = .03), and year of surgery (OR ≥ 1.56, P < .001 for all year categories vs. 1992–1994). Treatment at academic (OR 1.43, P = .003) and NCI-designated cancer centers (OR 5.50, P < .001) and by high-volume providers (OR 1.49, P < .001) was independently associated with continent reconstruction. CONCLUSIONS. Disparities in the utilization of continent urinary diversion after radical cystectomy suggest that demographic, socioeconomic, provider-based, and clinical variables predict the likelihood that those undergoing radical cystectomy will receive continent reconstruction. Regionalization of bladder cancer care may ameliorate many of the disparities noted but must be balanced against the risk imposed by a delay in care. Cancer 2006. © 2006 American Cancer Society.
Fast and low-cost search schemes by exploiting localities in P2P networks

Existing peer-to-peer (P2P) search algorithms generally target either the performance objective of improving search quality from a client's perspective, or the objective of reducing search cost from an Internet management perspective. Most existing work of designing and optimizing search algorithms in unstructured P2P networks addresses the trade-off between the two performance objectives. In contrast, our goal in this study is to attempt to achieve both objectives. Motivated by our observations on the content locality in the peer community and the localities of search interests of individual peers, we propose content-abundant cluster-selectively prefetching indices from responding peers (CAC-SPIRP), a fast and low-cost P2P searching algorithm. Our algorithm consists of two components. The first component aims to reduce the search cost by constructing a CAC, where content-abundant peers self-identify, and self-organize themselves into an inter-connected cluster providing a pool of popular objects to be frequently accessed by the peer community. A query will be first routed to the CAC, and most likely to be satisfied there, significantly reducing the amount of network traffic and the search scope. The second component in our algorithm is client oriented and aims to improve the quality of P2P search, called SPIRP. A client individually identifies a small group of peers who have the same interests as itself to prefetch their entire file indices of the related interests, minimizing unnecessary outgoing queries and significantly reducing query response time. Building SPIRP on the CAC Internet infrastructure, our algorithm combines both merits of the two components to achieve both performance objectives. Our trace-driven simulations show that CAC-SPIRP significantly improves the overall performance from both client's perspective and Internet management perspective.
Electron-Hole Condensation in Semiconductors: Electrons and holes condense into freely moving liquid metallic droplets, a plasma phase with novel properties

In Ge and Si, and also in Ge-Si alloys (74), there is extensive evidence for the stable binding of electrons and holes into a cold plasma of constant density, which undergoes a phase separation. Liquid metallic drops 1 to 300 microm in size are formed, with lifetimes ranging from 0.1 to 600 microsec. For Ge a surprising amount is known: the phase diagram, the surface energy, the work function, the decay kinetics. Much less is known for Si. There is good agreement between theoretical and experimental values of the liquid density, the critical density, the critical temperature, and the binding energy. The stability of the liquid phase is strikingly dependent on band structure. The multivalley structure and mass anisotropy of Si, Ge, and Ge-Si, together with their indirect band gap, are no doubt responsible for the observed stability in these crystals. In the similar semiconductor gallium phosphide, drops have not yet been observed, most likely because the high impurity content traps the excitons. In gallium arsenide the existence of drops is controversial (75). Undoubtedly drops will be found to exist in other semiconductors, perhaps at even higher temperatures. This is an exciting field for the experimentalist; new phenomena are being rapidly discovered, usually before they are predicted. For the theorist, the electron-hole drop is of high intrinsic interest. It represents the first example of a quantum liquid of constant density in a periodic crystal lattice. A number of challenging experimental and theoretical problems remain.
EFFECT OF MALE POLLEN DONOR AND FEMALE SEED PARENT ON ALLOCATION OF RESOURCES TO DEVELOPING SEEDS AND FRUIT IN CHAMAECRISTA FASCICULATA (LEGUMINOSAE)

In Chamaecrista fasciculata, fruit abortion levels are high and seed mass is highly variable, necessary preconditions for differential resource allocation of the female to seed and fruit sired by different males. This study investigated the relative role of pollen donor and seed arent on the allocation of resources to developing seed and fruit, and assessed the role of genetic relatedness in contributing to any observed paternal effect in C. fasciculata
Determination of urinary excretion of a methadone metabolite as an indirect measurement of methadone metabolism in the rat

Abstract The relationship between the metabolism of methadone in the rat liver and the urinary excretion of methadone metabolites was studied. The concentrations of water-soluble metabolite ([ 14 C]WSM) of methadone in the liver and urine, expressed as a percentage of total 14 C in the liver or urine, increased with time after [ 14 C]methadone administration. Acute administration of desipramine (20 mg/kg, ip) I hr before sc administration of [ 14 C]methadone (5 mg/kg body weight, 3 μCi/mg) decreased the percentage of total 14 C as [ 14 C]WSM in both liver and urine 3 hr after [ 14 C]methadone administration. Conversely, phenobarbital pretreatment increased the percentage of total 14 C as [ 14 C]WSM in liver and urine. The changes in percentage of total 14 C as [ 14 C]WSM in the urine of rats pretreated with desipramine and phenobarbital were directly proportional to the changes of this percentage in the liver. When the data obtained from rats pretreated with desipramine, phenobarbital, diazepam, and methadone were pooled together, a highly significant correlation between the percentage of total 14 C as [ 14 C]WSM in the urine and liver was established. The results suggest that determination of percentage of total 14 C as [ 14 C]WSM in urine reflects the rate of methadone metabolism in the liver and provides an indirect measurement of methadone metabolism in vivo .
Pharmacologic independence of subfornical organ receptors mediating drinking

In rats with chronically implanted cannulae in the subfornical organ (SFO), the relationship between cholinergic- and angiotensin (AII)-induced drinking was investigated pharmacologically. All substances were injected via SFO cannulae which did not rupture ventricular ependyma. Pretreatment with low doses of the muscarinic antagonist atropine abolished carbachol-induced drinking, while nicotinic antagonists had no effect. Nonetheless, pretreatment with much larger doses of atropine had no effect on AII-induced drinking. Similarly, relatively small doses of the AII antagonist, saralasin, blocked AII-induced drinking, yet a much larger dose of saralasin had no effect on carbachol-induced drinking. The receptors mediating cholinergic- and AII-induced drinking therefore cannot be in series and must be in parallel. A hypothesis is proposed to account for this independence and for the significance of the SFO cholinergic innervation.
Analysis of substrate specificity of Schizosaccharomyces pombe Mag1 alkylpurine DNA glycosylase

DNA glycosylases specialized for the repair of alkylation damage must identify, with fine specificity, a diverse array of subtle modi- fications within DNA. The current mechanism involves damage sensing through interrogation of the DNA duplex, followed by more specific recognition of the target base inside the active site pocket. To better understand the physical basis for alkylpurine detection, we determined the crystal structure of Schizosaccharo- myces pombe Mag1 (spMag1) in complex with DNA and performed a mutational analysis of spMag1 and the close homologue from Saccharomyces cerevisiae (scMag). Despite strong homology, spMag1 and scMag differ in substrate specifi- city and cellular alkylation sensitivity, although the enzymologi- cal basis for their functional differences is unknown. We show that Mag preference for 1,N 6 -ethenoadenine (eA) is influenced by a minor groove-interrogating residue more than the composition of the nucleobase-binding pocket. Exchanging this residue between Mag proteins swapped their eA activities, providing evidence that residues outside the extrahelical base-binding pocket have a role in identification of a particular modification in addition to sensing damage.
Incorporation of microcrystals by growing protein and virus crystals

In the course of time-lapse video and atomic force microscopy (AFM) investigations of macromolecular crystal growth, we frequently observed the sedimentation of microcrystals and three-dimensional nuclei onto the surfaces of much larger, growing protein or virus crystals. This was followed by the direct incorporation over time of the smaller crystals into the bulk of the larger crystals. In some cases, clear indications were present that upon absorption of the small crystal onto the surface of the larger, there was proper alignment of the respective lattices, and consolidation proceeded without observable defect formation, i.e., the two lattices knitted together without discontinuity. In the case of at least one virus crystal, cubic satellite tobacco mosaic virus (STMV), addition of three-dimensional nuclei and subsequent expansion provided the principal growth mechanism at high supersaturation. This process has not been reported for growth from solution of conventional crystals. In numerous other instances, the lattices of the small and larger crystals were obviously misaligned, and incorporation occurred with the formation of some defect. This phenomenon of small crystals physically embedded in larger crystals could only degrade the overall diffraction and materials properties of macromolecular crystals.
Macro- and microtribology of magnetic rigid-disk storage devices

Abstract This invited paper presents the state-of-the-art of our current understanding of the tribology of magnetic rigid-disk storage devices. Theories of friction and stiction, interface temperatures, wear and lubrication relevant to head-disk interfaces in disk drives are presented. Very smooth surfaces and ultra-low flying heights required for ultra-high recording densities present challenges and opportunities to tribologists and material scientists unparalleled in any other industry.
Evaluation of the methods for calculating the concentration-dependent diffusivity in binary systems

Boltzmann and Matano developed a procedure for the solution to Fick’s second law when the diffusivity is a function of concentration. The procedure requires the determination of the so-called Matano interface. The accuracy of the resulting solution depends heavily on the precise location of the Matano interface, the determination of which is laborious and often inaccurate. Three alternative procedures by Sauer and Freise, Wagner, and den Broeder, modifications to the original Boltzmann-Matano (B-M) method, were developed such that the diffusivity can be calculated without having to determine the location of the Matano interface. However, none of these derivations quantifies the extent to which the modified methods arrive at the same result as that obtained from the standard B-M analysis. This article serves to apply the B-M method, and the modification suggested by den Broeder, to various analytical concentration profiles containing different degrees of noise and to compare the results quantitatively. In addition to these analytical functions, concentration profiles obtained from interdiffusion experiments were studied. The two methods are shown to be equivalent in terms of the accuracy of the result. The advantages or disadvantages of one method over the other are illustrated with examples.
Physical Measurement Interrelationships of Turkeys Used in Further Processing

Abstract TURKEY carcass conformation may be expressed in terms of body weight, breast width, keel length, body depth, and other measurement standards. Geneticists have traditionally used these measurements as guides toward improving the market quality of breeding stock. Now with the advent of mechanized processing and deboning methods, measurement criteria must be reviewed and expressed in terms of their usefulness in developing automated processing machines and conveyorized deboning techniques. The objective of this study was to establish turkey physical measurement guidelines that would be useful to equipment manufacturers in their research and development. The interrelation of these physical measures are also presented. Latimer et al. (1926) present the general anatomical specifications and variability of the turkey hen. They found the percentage weights of the turkey viscera closely resembled the similar percentages in the chicken, but the musculature of the turkey was somewhat heavier. The skeleton weights and the lengths of the…
Quantum-confined Stark effects in interdiffused semiconductor quantum dots

Quantum-confined Stark effect in zero-dimensional semiconductor quantum-dot (QD) has attracted considerable interest due to the potential applications in electro-optic modulation and quantum computing. Composition interdiffusion occurs easily during the high temperature epitaxial growth or ex situ annealing treatment, therefore understanding the effects of interdiffusion is essential for device design and modeling. However, relatively little attention has been devoted to a systematic study of this effect. In this paper, the effects of isotropic interdiffusion on the optical transition energy of self-assembled InAs/GaAs QD structure under an electric field have been investigated theoretically. Our three-dimensional QD calculation is based on coupled QDs with different shapes arranged periodically in a tetragonal superlattice, taking into account the finite band offset, valence-band mixing, strain, and effective mass anisotropicity. The electron and hole Hamiltonians with the interdiffusion effect are solved in the momentum space domain. Our results show that isotropic three-dimensional In-Ga interdiffusion will makes the Stark shift become more symmetry about F=0 in asymmetric lens-shaped and pyramidal QDs, implying the reduced build-in dipole momentum. The interdiffusion also leads to enhanced Stark shift with more prominent effects to QDs that are under larger electric fields.