cssi/SciSciGPT-SciSciNet huggingface dataset:
A statistical deformation model (SDM) based regularizer for non-rigid image registration: application to registration of multimodal prostate MRI and histology

Free form deformation (FFD) is a popular algorithm for non-linear image registration because of its ability to accurately recover deformations. However, due to the unconstrained nature of elastic registration, FFD may introduce unrealistic deformations, especially when differences between template and target image are large, thereby necessitating a regularizer to constrain the registration to a physically meaning transformation. Prior knowledge in the form of a Statistical Deformation Model (SDM) in a registration scheme has been shown to function as an effective regularizer. With a similar underlying premise, in this paper, we present a novel regularizer for FFD that leverages knowledge of known, valid deformations to train a statistical deformation model (SDM). At each iteration of the FFD registration, the SDM is utilized to calculate the likelihood of a given deformation occurring and appropriately influence the similarity metric to limit the registration to only realistic deformations. We quantitatively evaluate robustness of the SDM regularizer in the framework of FFD through a set of synthetic experiments using brain images with a range of induced deformations and 3 types of multiplicative noise - Gaussian, salt and pepper and speckle. We demonstrate that FFD with the inclusion of the SDM regularizer yields up to a 19% increase in normalized cross correlation (NCC) and a 16% decrease in root mean squared (RMS) error and mean absolute distance (MAD). Registration performance was also evaluated qualitatively and quantitatively in spatially aligning ex vivo pseudo whole mount histology (WMH) sections and in vivo prostate MRI in order to map the spatial extent of prostate cancer (CaP) onto corresponding radiologic imaging. Across all evaluation measures (MAD, RMS, and DICE), regularized FFD performed significantly better compared to unregularized FFD.
Assessing the elements contributing to a mapping deficit A targeted treatment study

Aphasic patients with excellent comprehension of word meanings frequently fail to understand simple declarative sentences in which either of two nouns could reasonably serve as agent of a transitive action. This study employed targeted treatment of this comprehension problem in a chronic aphasic patient (E.A.) in an attempt to isolate the source or sources of his comprehension failure. Treatment exercises that relied on error feedback in sentence-picture matching or verification initially were not effective. Comprehension of active and passive sentences improved only after both structures were explicitly compared and linked to a picture. Subsequently E.A. maintained consistently accurate interpretation of both sentence types in the treatment exercises as long as the full sentence was available to him. E.A. learned to assign thematic roles using a limited set of cues in the surface structure. Although improvement was reported in untreated sentences, the degree of generalization and the level of performance differed across tasks and appeared to be attributable to cognitive impairments that were not addressed by the treatment. Results are interpreted as evidence suggesting that multiple impairments contribute to failure of sentence comprehension tasks.
Morphable Cache Architectures: Potential Benefits

Computer architects have tried to mitigate the consequences of high memory latencies using a variety techniques. An example of these techniques is multi-level caches to counteract the latency that results from having a memory that is slower than the processor. Recent research has demonstrated that compiler optimizations that modify data layouts and restructure computation can be successful in improving memory system performance. However, in many cases, working with a fixed cache configuration prevents the application/compiler from obtaining the maximum performance. In addition, prompted by demands in portability, long battery life, and low-cost packaging, the computer industry has started viewing energy and power as decisive design factors, along with performance and cost. This makes the job of the compiler/user even more difficult as one needs to strike a balance between low power/energy consumption and high performance. Consequently, adapting the code to the underlying cache/memory hierarchy is becoming more and more difficult.In this paper, we take an alternate approach and attempt to adapt the cache architecture to the software needs. We focus on array-dominated applications and measure the potential benefits that could be gained from a morphable (reconfigurable) cache architecture. Our results show that not only different applications work best with different cache configurations, but also that different loop nests in a given application demand different configurations. Our results also indicate that the most suitable cache configuration for a given application or a single nest depends strongly on the objective function being optimized. For example, minimizing cache memory energy requires a different cache configuration for each nest than an objective which tries to minimize the overall memory system energy. Based on our experiments, we conclude that fine-grain (loop nest-level) cache configuration management is an important step for a solution to the challenging architecture/software tradeoffs awaiting system designers in the future.
Identification of RAPD markers linked to a major rust resistance gene block in common bean.

Rust in bean (Phaseolus vulgaris L.), caused byUromyces appendiculatus (Pers.) Unger var.appendiculatus [ =U. phaseoli (Reben) Wint.], is a major disease problem and production constraint in many parts of the world. The predominant form of genetic control of the pathogen is a series of major genes which necessitate the development of efficient selection strategies. Our objective was focused on the identification of RAPD (random amplified polymorphic DNA) markers linked to a major bean rust resistance gene block enabling marker-based selection and facilitating resistance gene pyramiding into susceptible bean germplasm. Using pooled DNA samples of genotyped individuals from two segregating populations, we identified two RAPD markers linked to the gene block of interest. One such RAPD, OF10970 (generated by a 5′-GGAAGCTTGG-3′ decamer), was found to be closely linked (2.15±1.50 centi Morgans) in coupling with the resistance gene block. The other identified RAPD, OI19460 (generated by a 5′-AATGCGGGAG-3′ decamer), was shown to be more tightly linked (also in coupling) than OF10970 as no recombinants were detected among 97 BC6F2 segregating individuals in the mapping population. Analysis of a collection of resistant and susceptible cultivars and experimental lines, of both Mesoamerican and Andean origin, revealed that: (1) recombination between OF10970 and the gene block has occurred as evidenced by the presence of the DNA fragment in several susceptible genotypes, (2) recombination between OI19460 and the gene block has also occurred indicating that the marker is not located within the gene block itself, and (3) marker-facilitated selection using these RAPD markers, and another previously identified, will enable gene pyramiding in Andean germplasm and certain Mesoamerican bean races in which the resistance gene block does not traditionally exist. Observations of variable recombination among Mesoamerican bean races suggested suppression of recombination between introgressed segments and divergent recurrent backgrounds.
On the reversibility of environmentally induced alterations in abstract biological systems.

The environmentally induced alterations in structure of (M, ℜ) which were described previously (R. Rosen,Bull. Math. Biophysics,23, 165–171, 1961) are examined from the standpoint of determining under what circumstances they can be reversed by further environmental interactions. For simplicity we consider only the case of (M, ℜ)-systems possessing one “metabolic” and one “genetic” component. In the case of environmentally induced alteration of the “metabolic” component alone, a necessary and sufficient condition is given for the reversibility of the alteration. In the case of alteration of the “genetic” component, the situation becomes more complex; several partial results are given, but a full analysis is not available at this time. Some possible biological implications of this analysis are discussed.
Mathematical modeling for colloidal dispersion undergoing Brownian motion

An averaged motion approach for modeling Brownian dynamics for suspension systems of electrically charged particles in liquid is developed. The continuum model for the motion of particles consists of a system of integral equations coupled with a degenerate parabolic equation. Existence and uniqueness of global solution for the coupled system are established, and numerical results for the non-Newtonian viscosity of the mixture in terms of shear rate or Pechlet number are obtained. The model reveals some non-Newtonian properties such as the well-known shear thinning phenomenon for the viscosity of colloidal dispersions.
Brief Psychometric Analysis of the Self-Efficacy Teacher Report Scale

This study provides preliminary analysis of reliability and validity of scores on the Self-Efficacy Teacher Report Scale, which was designed to assess teacher perceptions of self-efficacy of studen...
Low-storage online estimators for quantiles and densities

The traditional estimator ξp, n for the p-quantile ξp of a random variable X, given n observations from the distribution of X, is obtained by inverting the empirical cumulative distribution function (cdf) constructed from the obtained observations. The estimator ξp, n requires O(n) storage, and it is well known that the mean squared error of ξp, n (with respect to p) decays as O(n-1). In this article, we present an alternative to ξp, n that seems to require dramatically less storage with negligible loss in convergence rate. The proposed estimator, ξp, n, relies on an alternative cdf that is constructed by accumulating the observed random variates into variable-sized bins that progressively become finer around the quantile. The size of the bins are strategically adjusted to ensure that the increased bias due to binning does not adversely affect the resulting convergence rate. We present an "online" version of the estimator ξp, n, along with a discussion of results on its consistency, convergence rates, and storage requirements. We also discuss analogous ideas for density estimation. We limit ourselves to heuristic arguments in support of the theoretical assertions we make, reserving more detailed proofs to a forthcoming paper.
Late Pliocene faunal turnover in the Turkana Basin, Kenya and Ethiopia

Analysis of a large sample of well-dated fossil mammals from localities in the Turkana Basin of Kenya and Ethiopia revealed sampling biases that affect patterns of faunal turnover during the late Pliocene. When these biases were accounted for, results indicated that 58 to 77 percent of the mammal species were replaced between 3.0 and 1.8 million years ago (Ma). Overall diversity increased from 3.0 to 2.0 Ma but then declined. No distinct turnover pulse is seen between 2.8 and 2.5 Ma; instead, the most significant period of faunal change began after 2.5 Ma and continued through 1.8 Ma.
Economic analysis of irrigation and deep tillage in soybean production systems on clay soil

Abstract A 5-year study (1987–1991) was conducted on a Tunica clay (clayey over loamy, montmorillonitic, non-acid, thermic Vertic Haplaquept) to determine effects of irrigation and deep tillage on soybean yields and economic returns. Irrigation increased average yield of the conventional check treatment (disked) by 57% (3020 vs. 1924 kg ha −1 ). Under irrigation, yields from all deep-tilled treatments and the conventional check treatment were similar and averaged 3066 kg ha −1 . Under non-irrigated conditions, yields from all deep-tilled treatments were similar, averaged 2829 kg ha −1 , and were higher than the conventional check treatment that averaged 1924 kg ha −1 . Average yields from the non-irrigated deep-tilled treatments were 92% as high as yields from comparable treatments with irrigation. Irrigation increased the average net returns of the conventional check treatment 75% ($206 vs. $118 ha −1 . Over the 5-year study, average net returns to all irrigated treatments were similar and ranged from $194 to $206 ha −1 . Net returns to the non-irrigated deep-tilled treatments averaged 156% higher than returns from the non-irrigated conventional check treatment ($302 vs. $118 ha −1 ) and was attributed to the higher yields of the deep-tilled treatments (2829 vs. 1924 kg ha −1 ). Net returns to the non-irrigated deep-tilled treatments also averaged 47% higher than returns from the irrigated conventional check treatment ($302 vs. $206 ha −1 ). This difference was attributed to the similarity of yields (2829 vs. 3020 kg ha −1 ) and the sizeable difference in specified costs of production ($335 vs. $481 ha −1 ) that favored non-irrigated production of soybean with deep-tillage.
Soil Quality Assessment of Tillage Impacts in Illinois

Successful soil quality assessment strategies are needed to improve our ability to manage soils sustainably. Our objective was to use a multivariate data set to determine whether recent adoption of notillage (NT) practices had altered soil quality in Illinois. In 1995 and 1996, we sampled thirty-six farm fields under conventional tillage (CT) or NT practices and relatively nondisturbed (ND) areas. Soils were Mollisols or Alfisols. Tillage or region affected 20 of the 23 parameters characterized. Soil chemical parameters were less variable than biological or physical measures. Principal component analysis (PCA) was used to assess soil quality overall. Principal component I (PC1) scores, which explained 39% of the total variance of the overall data set, were affected by tillage (ND > NT > CT) and increased with particulate and organic C and total N, biological activity, mineralizable N, and wet aggregate stability, and decreased with bulk density and dry aggregate mean weight diameter. The only significant factor contributing to PC2 was penetration resistance; PC2 explained 13% of the variance and decreased as follows: NT ≥ ND > CT. Multivariate assessment of soil quality indicated use of NT practices improved the biological and physical condition of the soil (0-15 cm) despite increased consolidation. It also showed that those biological and physical aspects of soils influenced by organic matter were the properties most altered by agronomic practices. Particulate organic matter (POM) was identified as a promising soil quality measure. A next step is to determine the biological and environmental relevance of a refined set of soil quality measures in conjunction with soil processes of regional concern.
Self-assembled epitaxial nanocomposite BaTiO3-NiFe2O4 films prepared by polymer-assisted deposition.

We present a new approach, cost-effective polymer-assisted deposition, to prepare self-assembled epitaxial BaTiO3−NiFe2O4 nanocomposite films on LaAlO3 substrates. Ferroelectric BaTiO3 is embedded ...
The effects of neutron irradiation on shear properties of monolayered PyC and multilayered PyC/SiC interfaces of SiC/SiC composites

Abstract The effect of neutron irradiation on mechanical properties at the fiber/matrix interface of SiC/SiC composites was evaluated. The materials investigated were Hi-Nicalon™ Type-S fiber reinforced chemically vapor infiltrated SiC matrix composites with varied interphases: monolayered pyrolytic carbon (PyC) or multilayered PyC/SiC. The neutron fluence was 7.7 × 1025 n/m2 (E > 0.1 MeV), and the irradiation temperature was 800 °C. Interfacial shear properties were evaluated by the fiber push-out test method. A modified shear-lag model was applied to analyze the interfacial shear parameters. Test results indicate that the interfacial debond shear strength and the interfacial friction stress for the multilayer composites were significantly degraded by irradiation. Nevertheless, the multilayer composites retained sufficient interfacial shear properties so that overall composite strength after neutron irradiation was unaffected. The actual mechanism of interphase property decrease for the multilayer composites is unknown. The interfacial shear properties of the irradiated monolayer composites appear unaffected.
Emerging infectious disease outbreaks: Old lessons and new challenges for obstetrician-gynecologists

Objective The purpose of this study was to summarize 3 recent high-profile infectious disease threats that have affected the United States: severe acute respiratory syndrome, West Nile virus, and anthrax. Study design A systematic review was conducted with the use of Medline searches, searches of the Centers for Disease Control and Prevention website, and review by experts at the Centers for Disease Control and Prevention. Results The 3 emerging infectious diseases pose very different threats: Severe acute respiratory syndrome is a newly identified pathogen that caused an international pandemic; the West Nile virus investigation involved an old pathogen that was identified in a new location; and the anthrax attacks involved the intentional introduction of a pathogen. Conclusion All 3 outbreaks highlight the importance of obstetrician-gynecologists keeping current with new information as it emerges. In this global environment, it is likely that novel disease threats will continue to emerge in the United States.
The initial growth of a radiation driven shock wave

Abstract The time development of a radiation driven shick wave is studied from the time of commencement of radiation of Lyman continuum, frequency 3.4 × 1015 sec−1, onto monatomic hydrogen, till a shock wave was formed. The shock wave was located from the examination of the reduced velocity distribution functions. A relaxation region with a bimodal velocity distribution was found between the shock wave and radiation front. The time development of the macroscopic properties of the atoms, protons and electrons is shown.
129I and 36Cl in dilute hydrocarbon waters: Marine-cosmogenic, in situ, and anthropogenic sources

Abstract The long-lived halogen radioisotopes 129I and 36Cl provide valuable information regarding the source of fluids in hydrocarbon systems and in localized areas where infiltration of younger meteoric water has occurred. Despite the utility of these two isotopes in providing time-signatures for fluid end-members, considerable uncertainty remains regarding the interpretation of “intermediate-age” waters in hydrologic systems. These waters are likely the result of the combination of two or more halogen sources at some time in the past, each with its own characteristic concentration and isotopic composition. In order to unravel the evolution of these “intermediate-age” waters, the effect that infiltration of meteoric water has on the isotopic composition of older formation waters is modeled. Also evaluated is the effect that the timing of dilution has on 129I and 36Cl signatures observed in the present, specifically, the hypothesis that halogen isotopic signatures imparted by the mixing of brine and meteoric waters early in the development of a sedimentary basin are quantitatively different from those imparted by the mixing of old brines with recent meteoric waters. The modeled results are compared to previously published isotopic data from production wells in the Fruitland Formation coalbed methane system. Portions of the basin preserve enough of the original brine source to retain 129I/I ratios roughly recording the age of deposition of organic matter (73–76 Ma) even where some degree of dilution by meteoric water has occurred. However, the 129I signatures of waters that presently contain less than 10% of the original formation water component indicate that mixing has occurred within the past 10 Ma, consistent with recently published 4He data. Both 36Cl concentrations and 36Cl/Cl ratios show that waters containing more than 10% formation water are all in secular equilibrium with the host formation coals. In contrast, waters with less than 1% of the original formation water’s Cl− content all have 36Cl/Cl ratios which are greater than secular equilibrium values, indicating the migration of meteoric water into the coal formation more recently than 2 Ma. Although 36Cl signatures in the Fruitland Formation are not significantly affected by anthropogenic input, 129I/I ratios in a subset of samples that retain less than 1% of the initial formation water component suggest input of anthropogenic 129I during the past 50 a.
Children’s sensitivity to pictorial depth information

Children, ranging in age from 3 years, 4 months to 5 years, 4 months, were tested for sensitivity to interposition, height in field, linear perspective, and retinal size under either restricted (monocular, head motionless) or unrestricted (binocular, head free) picture surface viewing conditions. All of the subjects’ relative depth responses (near vs. far) to two toy houses were remarkably accurate with interposition and or height in field pictorial depth information. Retinal size had relatively little control over their responses, and the addition of linear perspective resulted in no significant improvement. Performance was nearly equivalent under the two viewing conditions, indicating young children’s ability to take a “pictorial attitude.”
Eating behavior following stress in women with and without bulimic symptoms

Objective: This study examined the effects of an interpersonal stressor on subsequent calorie intake in females with (N=20) and without (N = 20) significant bulimic symptomatology.Method: Subjects participated in two laboratory sessions that differed according to experimental condition (stress versus no stress), completed self-report measures of mood and anxiety before and after the experimental task, and were provided with an array of snack foods after each session.Results: Counter to the hypothesis, women with bulimic symptoms did not differentially increase their intake when exposed to stress. However, results for the intake of each macronutrient indicated that both bulimic and control women increased their consumption of carbohydrates following the stressor. Thus, stress was related to increased carbohydrate consumption by all subjects but did not differentially affect the consumption of women with bulimic symptoms.Conclusions: It may be that women with bulimic symptoms are not differentially vulnerable to eating in response to stress or that current laboratory paradigms are unable to detect differences in eating following a stressor.
Environmental medicine: its introduction into a medical school primary care requirement.

Summary. One hundred and twelve medical students participating in a required 6-week primary-care rotation completed a pretest of environmental medicine knowledge and attitudes at the start of the rotation and a similar posttest on the last day of the rotation. Control group students were to participate in the usual weekly didactic sessions of the clerkship. Intervention students were given a booklet describing environmental considerations in clinical medicine and introducing them to the concept of risk assessment, three computer-assisted instruction cases, and a problem-based learning (PBL) exercise involving role-play. Because voluntary compliance with evaluation forms was poor during year one, during the second year students in the intervention group were required to return evaluation forms in order to sit for the course final examination. Knowledge and attitudes of both intervention and control groups were compared at baseline and at the end of the rotation. Students in the intervention group also completed process evaluations of the intervention materials. Students in both intervention and control groups increased knowledge gains significantly during the second year of the intervention, while neither group improved during year 1. This may have been due to a ‘spill-over’ effect among primary-care teachers implementing the intervention. Students ranked both environmental and occupational medicine of least importance in their training compared with eight other aspects of medicine, and this ranking did not improve with intervention. The PBL exercise was well received by the students. Of 28 evaluations, 27 ranked the session in the highest 3 of a 5-part Likert scale for worthwhile content, and 24 would recommend the session to a friend. When asked to list the most important things learned, 23 mentioned learning to look for additional information, and 12 mentioned realizing that the doctor does not know everything (and should admit that).
Potential model calculations and predictions for heavy quarkonium

(Dated: February 2, 2008)We investigate the spectroscopy and decays of the charmonium and upsilon systems in a potentialmodel consisting of a relativistic kinetic energy term, a linear conﬁning term including its scalarand vector relativistic corrections and the complete perturbative one-loop quantum chromodynamicshort distance potential. The masses and wave functions of the various states are obtained usinga variational technique, which allows us to compare the results for both perturbative and nonper-turbative treatments of the potential. As well as comparing the mass spectra, radiative widths andleptonic widths with the available data, we include a discussion of the errors on the parameterscontained in the potential, the eﬀect of mixing on the leptonic widths, the Lorentz nature of theconﬁning potential and the possible c¯cinterpretation of recently discovered charmonium-like states.1. INTRODUCTION
Formamidine Synergism of Pyrethroid Toxicity to Twospotted Spider Mites (Acari: Tetranychidae)

The toxicity of binary mixtures of formamidines and pyrethroids to Tetranychus urticae Koch was investigated and compared with the toxicity of their individual components. A synergistic interaction was observed with 85 of the 104 formamidines examined in binary mixtures with cypermethrin; 29 of these improved toxicity 5-fold or greater. With regard to the different pyrethroids, there was evidence for suggesting that formamidine synergism generally was greatest with cypermethrin and deltamethrin, intermediate with fluvalinate, flucythrinate, and fenpropathrin, and least with fenvalerate and permethrin. The four best overall pyrethroid synergists were N′-(2,4-dimethylphenyl)-N-methy 1- N -(pheny Ithio)formamidine (Upjohn-42564), N′ -(2,4,6,-trimeth yIpheny1)- N ,N-dimeth yIformamidine, N′-(3,4-methylenedioxypheny 1)- N ,N -dimethylformamidine, and chlordimeform. The greatest synergism of cypermethrin was a 24-fold enhancement by the methylenedioxyphenyl formamidine; synergism by this formamidine of other pyrethroids ranged from 8.9-fold to only 2.5-fold. Structure-activity relationship studies clearly indicated that the ability of formamidines to effect synergism of pyrethroids was not inextricably associated with their lethality in spider mites. Thus, highly active synergists included some formamidines that were directly lethal to spider mites and some that demonstrated little, if any, direct toxicity to this organism.
Sea-surface topography near the Gulf Stream

Abstract The topography of the sea surface between Bermuda and the east coast of North America is calculated using ship-drift observations. The effect of wind is also calculated. For comparison, the annual mean change in level across the Gulf Stream is determined from hydrographic data and estimates of the deep flow. The change in level by the second method is found to be 100 cm, as compared with 110 cm from the ship-drift calculations. The slope of sea level along the Atlantic coast is discussed. The rise of sea level from south to north, as reported by geodetic levelling, is concluded to be inconsistent with the requirements of the observed flow of the Gulf Stream.
Comparison of the osmolyte transport properties induced by trAE1 versus IClswell in Xenopus oocytes.

During cell swelling, cells release organic osmolytes via a volume-activated channel as part of the regulatory volume decrease. The erythrocyte membrane protein AE1 (band 3), has been shown to be involved in regulatory volume responses of fish erythrocytes. Previous studies showed that the expression of trout AE1 in Xenopus laevis oocytes induces band 3 anion exchange activity and organic osmolyte channel activity. However, an endogenous swelling-activated anion channel, I C l s w e l l , is present in Xenopus oocyte membranes. Therefore, it is not yet known whether a new organic osmolyte channel is formed or whether the endogenous channel, I C l s w e l l , is activated when trout AE1 is expressed in the oocytes. The purpose of this study was to determine whether the expression of trout AE1 in Xenopus oocytes leads to the formation and membrane insertion of a new organic osmolyte channel or activates I C l s w e l l . To differentiate between the two possibilities, we compared the time courses, pH profiles and inhibitor sensitivities of both trout AE1 and I C l s w e l l . The results of taurine-uptake experiments show that the time courses and pH levels for optimum expression of trout AE1 and I C l s w e l l differ significantly. The inhibitor sensitivities of the organic osmolyte channel mediated by trout AE1 and I C l s w e l l are also significantly different, strongly suggesting that the expression of trout AE1 in Xenopus oocytes does not activate I C l s w e l l , but rather forms a new organic osmolyte channel.
ST2 in Heart Failure: Where Does This New Marker Fit in?

A member of the interleukin-1 receptor family, soluble ST2 (sST2), is a powerful marker of myocyte strain and vascular stress in heart failure and acute coronary syndrome, as well as numerous other cardio-pulmonary disease states. It is clinically useful in both the emergency department and hospital setting for predicting disease prognosis and mortality. Together with patient-specific characteristics, sST2 also has an increasing role to play as a tool to guide therapeutic interventions. We will discuss where this important new biomarker fits in now and its promise for the future.
Summer Courses in Computing for the Gifted and Talented: How Much Can Be Accomplished in Two Weeks?.

When one considers summer sessions for gifted students, it is immediately apparent that computer courses are extremely popular. The objectives of such classes vary tremendously from literacy and appreciation to computer aided skill building to learning to program. The purpose of this paper is to describe a two week summer course which successfully develops mathematical problem solving, promotes understanding of advanced mathematical concepts, and allows students to learn a gret deal of programming.
Developments in African Governance since the Cold War: Beyond Cassandra and Pollyanna

Twenty years ago, most African countries seemed permanently mired in malgovernance and repression. The end of the Cold War triggered two contrasting developments: governance improvement associated with the end of superpower competition, and deterioration caused by the resurgence of suppressed ethnic conflicts. Based on a variety of evidence, three subperiods can be identified: fragile governance progress from 1989 to 1995; backsliding associated largely with civil conflict between 1996 and 2002; and resumption of progress in recent years. These broad trends mask major intercountry differences—with Ghana the best-known case of improvement and Zimbabwe the worst case of reversal. Overall, African governance is now somewhat better than it was two decades ago. However, the progress is fragile, and improvements in administrative and economic governance have lagged behind those on the political front. Consolidating democracy will thus require institutional capacity building through a combination of appropriate civil society efforts and constructive external pressure to strengthen accountability. Resume: Il y a vingt ans, la plupart des pays africains semblaient enfouis pour de bon sous les problemes de mauvaise gestion et de repression. La fin de la guerre froide a declenche deux impulsions contradictoires : une amelioration de la gestion gouvernementale associee a la fin de la competition des superpouvoirs, et une deterioration causee par la resurgence des conflits ethniques. Trois periodes peuvent etre identifiees si l'on se base sur les sources disponibles : Le progres gouvernemental fragile entre 1989 et 1995 ; la regression due largement aux conflits civils entre 1996 et 2002 ; et le retour du progres dans les dernieres annees. Ces tendances generales masquent des disparites majeures entre certains pays, comme le Ghana, cas modele d'amelioration, et le Zimbabwe, a l'autre extreme des cas de regression. De facon generale, la gestion gouvernementale en Afrique est meilleure qu'il y a vingt ans. Cependant, le progres effectue reste fragile, et les ameliorations au niveau administratif et economique restent a desirer compare aux ameliorations du domaine politique. La consolidation de la democratie va ainsi necessiter un mouvement institutionnel demandant a la fois des efforts de la societe civile et une pression constructive provenant de l'exterieur pour renforcer le niveau de deontologie gouvernementale.
Linear regression with delta-modulated integrated signals

Abstract An estimate of the accuracy of linear regression is given for instrumentation data where the signal is integrated and DPCM-quantized before processing.
Searching for polymorphisms that affect gene expression and mRNA processing: example ABCB1 (MDR1).

Cis-acting genetic variations can affect the amount and structure of mRNA/protein. Genomic surveys indicate that polymorphisms affecting transcription and mRNA processing, including splicing and turnover, may account for main share of genetic factors in human phenotypic variability; however, most of these polymorphisms remain yet to be discovered. We use allelic expression imbalance (AEI) as a quantitative phenotype in the search for functionalcis-acting polymorphisms in many genes includingABCB1 (multidrug resistance 1 gene, MDR1, Pgp). Previous studies have shown that ABCB1 activity correlates with a synonymous polymorphism. C3435T; however, the functional polymorphism and molecular mechanisms underlying this clinical association remained unknown. Analysis of allele-specific expression in liver autopsy samples and in vitro expression experiments showed that C3435T represents a main functional polymorphism, accounting for 1.5-to 2-fold changes in mRNA levels. The mechanism appears to involve increased mRNA turnover, probably as a result of different folding structures calculated for mRNA with the Mfold program. Other examples of the successful application of AEI analysis for studying functional polymorphism include5-HTT (serotonin transporter, SLC6A4) andOPRM1 (μ opioid receptor). AEI is therefore a powerful approach for detectingcis-acting polymorphisms affecting gene expression and mRNA processing.
Weighted Flow Algorithms (WFA) for stochastic particle coagulation

Stochastic particle-resolved methods are a useful way to compute the time evolution of the multi-dimensional size distribution of atmospheric aerosol particles. An effective approach to improve the efficiency of such models is the use of weighted computational particles. Here we introduce particle weighting functions that are power laws in particle size to the recently-developed particle-resolved model PartMC-MOSAIC and present the mathematical formalism of these Weighted Flow Algorithms (WFA) for particle coagulation and growth. We apply this to an urban plume scenario that simulates a particle population undergoing emission of different particle types, dilution, coagulation and aerosol chemistry along a Lagrangian trajectory. We quantify the performance of the Weighted Flow Algorithm for number and mass-based quantities of relevance for atmospheric sciences applications.
Towards integrated circuit thermal profiling for reduced power consumption: Evaluation of distributed sensing techniques

Reducing the power consumption in integrated circuits will require the use of several techniques, many of which depends on accurate on-chip temperature measurement. Simultaneously, power consumption can be reduced by using smaller integration scales of System-on-Chip (SoC). This will require a comprehensive solution to the ensuing more frequent problems of reliability-related events. This paper introduces the use of an on-chip sensor network to monitor reliability-related parameter and to adapt local chip components to ensure continuing efficient operation with reduced power consumption. The sensor network design is constrained to present a negligible footprint in terms of the chip internal bandwidth use, power consumption and number and area of integrated components. In this context, this paper considers the problem of monitoring the time evolution of the complete chip thermal profile. Different distributed sensing and source compression schemes that leverage on the physical properties of heat propagation and networking of sensors are evaluated in terms of bandwidth and power consumption saving potential. Simulation results show the potential for these techniques to provide useful savings in on-chip communication bandwidth. Considering strict implementation complexity constraints, distributed source coding through binning is the evaluated technique that shows best performance.
Economics and tourism.

Abstract This paper surveys applications of economic analysis to tourism. Application of economic logic and tools, such as consumer and production theory, market structure, deductive modeling, cost-benefit analysis, econometric analysis, and multiplier analysis, are all discussed as they relate to tourism. The economic perspective on tourism provides insights into the types of choices and decisions which consumers, private sector suppliers, government agencies, and policymakers make. It also provides a structure for identifying which types of data should be gathered, organized, and interpreted for purposes of better understanding tourism markets, constructing forecasts, and aiding in policy choices involving resource allocation.
Axonal Degeneration Is Blocked by Nicotinamide Mononucleotide Adenylyltransferase (Nmnat) Protein Transduction into Transected Axons

Axonal degeneration is an early and important component of many neurological disorders. Overexpression of nicotinamide mononucleotide adenylyltransferase (Nmnat), a component of the slow Wallerian degeneration (Wlds) protein, protects axons from a variety of insults. We found that transduction of Nmnat protein into severed axons via virus-like particles prevented axonal degeneration. The post-injury efficacy of Nmnat indicates that its protective effects occur locally within the axon and provides an opportunity to develop novel agents to treat axonal damage.
Structure and Engineering of l-Arabinitol 4-Dehydrogenase from Neurospora crassa

Abstract l -Arabinitol 4-dehydrogenase (LAD) catalyzes the conversion of l -arabinitol into l -xylulose with concomitant NAD+ reduction. It is an essential enzyme in the development of recombinant organisms that convert l -arabinose into fuels and chemicals using the fungal l -arabinose catabolic pathway. Here we report the crystal structure of LAD from the filamentous fungus Neurospora crassa at 2.6 A resolution. In addition, we created a number of site-directed variants of N. crassa LAD that are capable of utilizing NADP+ as cofactor, yielding the first example of LAD with an almost completely switched cofactor specificity. This work represents the first structural data on any LAD and provides a molecular basis for understanding the existing literature on the substrate specificity and cofactor specificity of this enzyme. The engineered LAD mutants with altered cofactor specificity should be useful for applications in industrial biotechnology.
Listening to users in a manufacturing organization: a context-based approach to the development of a computer-supported collaborative work system

Abstract This paper reports the findings of a field research effort to develop a computer-supported collaborative work (CSCW) system in a power tool organization and provides an overview of the features of this system. It presents the customer-driven, context-based methodology that was used to capture the workflow and the critical issues that must be addressed by the CSCW system. It also describes the evaluation techniques and performance measures that were used to compare the resulting system with the existing product development system in the organization. It was found that a combination of ethnographic and human-centered design methodologies is a powerful approach for capturing information about stakeholder needs and using it to develop a CSCW system in such organizations. Through evaluative ethnography it was possible to determine tasks that were feasible and others that were inappropriate for integration into the CSCW system. This methodology also identified issues that hindered the adoption of the CSCW system, permitting strategies for adoption to be proposed that might serve as guidelines to designers of future CSCW systems. Lastly, this development, implementation, and evaluation of a CSCW system in an industrial environment demonstrate its effectiveness to other similar organizations that could benefit from the use of CSCW systems. Relevance to industry This paper describes the development of a computer-supported collaborative work (CSCW) system in an actual manufacturing organization using a human-centered, context-based design methodology. The evaluation of the resulting CSCW system demonstrates the effectiveness of the methodology employed, as well as the potential CSCW systems have to address the needs of product development organizations.
Failure analysis of tire tread separations

In-service catastrophic radial tire failure is often a separation of the tread and outer steel belt from the tire casing and inner steel belt. These separations generally occur in the field at high temperature and high speed. This paper presents a catalog of surface characteristics that define the various types of rubber cracking that take place during a tire belt-leaving-belt separation. A mechanism that explains the generation of the rapid tearing surface is used to detail the variation found in forensic examinations.
Life Cycle Cost for a Solar Heating and Cooling System

Solar absorption cooling has been an intriguing research subject since 1970. However, it is not widely applied because the first cost of the system is high, the commercial hot water absorption chiller is not mature, the site demonstration and evaluation are not adequate and the price of conventional fossil energy sources is relatively low. This paper investigates the commercialization potentials of solar absorption cooling and solar heating system by comparing the life cycle cost between it and the conventional electrical chiller cooling and gas-fired boiler heating system. A computational model has been programmed in the Engineering Equation Solver (EES) to analyze the economical performances of the two systems applied to a dedicated building. The model considers the cost of capital, installation, operation and maintenance, the discount rate, the fuel prices, and the inflation rates. The result of the model indicated that given the present fuel cost, the solar absorption cooling and heating system is not as economic as the conventional system especially when its size is small. However, according to the sensitivity analysis carried, the solar absorption cooling and heating system could compete with the conventional cooling and heating system when the electricity price and fuel inflation increase.Copyright © 2009 by ASME
Environmental enrichment enhances recovery of function but exacerbates ischemic cell death

Prior exposure to brief 'conditioning' episodes of ischemia protects hippocampal CA1 neurons against a subsequent more severe ischemic insult. However, protected cells exhibit abnormal function and as survival times are extended this ischemic tolerance dissipates and cells begin to die. In this study, we sought to determine whether environmental enrichment could alter the above pattern of delayed cell death and functional impairment in a gerbil model of ischemic tolerance. Gerbils received either ischemic preconditioning, 5 min of ischemia without preconditioning or sham surgery. Three days after ischemia, gerbils were placed in either an enriched environment or standard laboratory housing. Open field habituation was assessed 3, 7, 10, 30 and 60 days after ischemia. Subsequently, animals were trained in two versions (win-shift and win-stay) of a T-maze task. Following behavioral testing, extracellular CA1 field potential amplitudes and CA1 cell counts were determined. Initial open field activity was significantly higher in all experimental groups compared to sham animals (P<0.001). By 60 days, enriched ischemic preconditioned and enriched ischemic gerbils were not different than shams whereas non-enriched, ischemic preconditioned and ischemic gerbils continued to have higher activity scores (P<0.05). Preconditioned and enriched ischemic animals learned the win-shift T-maze problem as quickly as shams while non-enriched ischemic gerbils were severely impaired compared with all other groups (P<0.001). Only the sham and enriched preconditioned groups readily acquired the win-stay paradigm. CA1 field potential amplitudes were lower (P<0.05) in ischemic than sham gerbils irrespective of treatment. Surprisingly, CA1 cell counts were significantly lower (P<0.01) in enriched versus non-enriched ischemic preconditioned animals. These data demonstrate that early, intensive intervention after ischemia can improve functional outcome but that this is accompanied by increased brain damage. Careful consideration needs to be given to the timing of rehabilitation after stroke and related types of brain injury.
Studies Directed toward the Total Synthesis of Lancifodilactone G: An Expeditious Route to the ABC Subunit

An efficient entry to the ABC network of lancifodilactone G is outlined. The C ring is constructed by way of enyne ring-closing metathesis. The AB component is established via a base-mediated biomimetic oxy-Michael addition−lactonization sequence.
Optimization of multiple overlapping thin slab acquisition (MOTSA) MRA

This optimization treats 2D and 3D single-slab Time-Of-Flight (TOF) as opposite limiting cases of MOTSA. It was approached from a general theoretical analysis through imaging parameters such as flow velocity, T1 of blood and surrounding tissue, and size of the region of interest. The potential CNR improvement from using magnetization transfer contrast (MTC) in conjunction with the MOTSA sequence was also examined. A mathematical model was built and tested to describe evolution of hydrogen magnetization under radio frequency pulses, and the computer simulations in turn were used to determine an optimized combination of flip angle, repetition time (TR) and slab thickness. A flat slab-selection profile was used, under the constraints of fixed anatomical coverage, total acquisition time and resolution. Results of phantom and volunteer studies agree with the computer simulation. Conclusions of this study are (1) the flow model used is adequate for imaging the human anterior cerebral arteries, a representative of intracranial arteries; (2) combination of MTC (using a binomial pulse) with MOTSA does not improve CNR; (3) the optimum MOTSA technique has the shortest TR possible, a slab thickness in which flowing blood receives approximately two flips, and a flip angle chosen to yield the maximum vessel-to-background CNR for that particular TR and slab thickness.