cssi/SciSciGPT-SciSciNet huggingface dataset:
Forces Induced by Peak Systolic Flows in Asymmetric Endovascular Grafts

Endovascular repair (EVAR) has emerged as an alternative, less-invasive surgical technique for the treatment of patients diagnosed with abdominal aortic aneurysms (AAAs). The anatomical pathway of blood flow in the abdominal aorta is restored by the implantation of an endovascular graft (EVG), effectively depressurizing the aneurysm and initiating a remodeling process of the diseased aorta. The short-term results of endovascular grafting are promising, but its long-term success has been compromised by the occurrence of graft migration and detachment, which induce endoleaks or incomplete occlusion of the aneurysm from the blood circulation. The forces induced by the blood as it flows through the graft are believed to be a factor of probable cause in the partial detachment from its proximal and distal anchoring points and the migration of the graft downstream. The purpose of this study is to utilize analytical tools to provide an estimation of the forces required to secure the graft proximally when relying only on stresses induced by the flow.© 2003 ASME
General Confinement Model Based on Nonlocal Information

The confinement effect has been of significant importance for improving the resilience against extreme compression loadings such as seismic excitations. Notwithstanding the accuracy of previous confinement models, some challenges remain regarding their applicability. The previous approaches often build on structure-dependent parameters necessitating intractable calibrations, and their formulations are defined on an integration point or a small portion of the structure, thereby precluding general applicability to complicated real-scale RC structures. Here a general confinement model is proposed in a novel way that it can harness physical information inside the real-scale system. The information is denoted nonlocal information, since it is processed by the nonlocal formulation for assuring the mesh-objectivity. Physically, the nonlocal information provides the proximity to adjacent stiff materials and boundaries through the information index suggested herein. Numerical issues regarding the parallel computing and the optimal selection of the length parameter for the nonlocal formulation are also addressed. The unprecedentedly broad applications include a solid column, a hollow column, a rectangular wall, a T-shaped wall, and even a wall with opening, which strongly bear out the promising potential and universality of the novel confinement model.
High-Speed Microphotographic Laboratory

Lawrence Livermore National Laboratory's (LLNL's) High-Speed Microphotographic Laboratory provides a facility for studying rapidly evolving microstructures. In particular, the exploding of wires and foils and their interactions with high explosives are of particular interest. The facility combines high-speed electronic framing and streak cameras with the appropriate specialized optics, spectrographs, and laser illumination to record events with a few nanoseconds and micrometers of temporal and spatial resolutions, respectively. Velocity and spectral data are also used to compute pressures with better than kilobar resolution.
Esophageal dilation for endosonographic evaluation of malignant esophageal strictures is safe and effective.

Abstract OBJECTIVE: Endoscopic ultrasound (EUS) is accepted as the most accurate modality for T- and N-staging of esophageal cancer, but some malignant strictures prevent passage of the echoendoscope beyond the level of the tumor. This incomplete evaluation may decrease staging accuracy. Previous studies have yielded conflicting results regarding the safety and efficacy of esophageal dilation for EUS. METHODS: We prospectively evaluated 267 consecutive patients undergoing EUS for esophageal carcinoma staging at our institution over a 66-month period to determine the number of patients requiring dilation for EUS examination, the success of dilation, safety of dilation, and clinical importance. RESULTS: Among 267 endosonographic examinations of the esophagus, 81(30.3%) required dilation to advance the echoendoscope beyond the level of the stricture. After dilation was performed, the echoendoscope could be passed through the stricture in 69 patients (85.2%), and in 63 of 67 of the patients dilated to ≥14 mm (94.0%). No complications have occurred secondary to the dilations performed to permit completion of the endosonographic examination. Tumor staging by EUS after dilation was T2 (14.8%), T3 (56.8%), and T4 (21.0%), nodal staging N0 (14.6%) and N1 (75.3%); and M1 (9.9%). CONCLUSIONS: We conclude that incremental, stepwise dilation of malignant strictures to 14 mm is safe and effective in permitting echoendoscope passage beyond the stenosis. The presence of a malignant stricture does not seem to diminish the utility of EUS staging of esophageal cancer.
Fluoride induced isomerization of cobalt diene complexes

Abstract A metal-mediated addition of two carbenes across an alkyne is employed for the synthesis of (2-phenylsulfonyl)-1,3-dienes. Control of diene stereochemistry is achieved through an unprecedented fluoride-catalyzed isomerization of the cobalt diene intermediates.
Mrs. John Marshall Harlan's Memories: Hierarchies of Gender and Race in the Household and the Polity

While legal papers and case decisions have been the traditional focus of judicial biography, the family papers of Justice John Marshall Harlan the Elder demonstrate the importance for understanding a judge's conception of the polity of shifting our sights to the household. Historians of the 19th century have overestimated the distance between the private and the public spheres. The memoirs of Harlan's wife Malvina offer us unparalleled, and hitherto neglected, testimony. Her depiction of the antebellum Harlan household shows its two hierarchies based on assumptions of fundamental differences—those of gender and of race—and both positing a benevolent white male paternalist at their apex. Malvina Harlan's memoirs indicate the lifelong persistence of this paternalism in her own relationship with Justice Harlan and in his relationship with a black servant. These patterns of hierachy, separation, and mutual devotion were essential to Harlan's understanding of his family identity and personal duty. His famous dissents in favor of black civil rights protections and his lapses from his color-blind rule have their roots in this paternalism even as Harlan came to embrace the racial egalitarianism of the Civil War amendments.
On the shape and size of market areas

How should the suppliers of a commodity be located so as to generate the greatest amount of welfare per unit area? Welfare is defined as consumers' surplus plus producers' profits. Costs of production are assumed to be linear functions of output identical for all firms and at all locations. Consumers are distributed in an unbounded two dimensional space at uniform density. They have identical linear demand functions. We determine both the optimal shape and the optimal radius of a representative firm's market area and compare them to those under free entry; the Loschian case of monopolistic competition. The general shape is that of rounded hexagons (or hexagonally flattened circles) with hexagons and circles as limiting cases. When fixed costs are high and firms are few, free entry creates fewer firms than is optimal, contrary to the well-known results for a free entry equilibrium in non-spatial monopolistic competition.
The occurrence of chitin in the hemocytes of invertebrates

The light-organ symbiosis of Euprymna scolopes, the Hawaiian bobtail squid, is a useful model for the study of animal–microbe interactions. Recent analyses have demonstrated that chitin breakdown products play a role in communication between E. scolopes and its bacterial symbiont Vibrio fischeri. In this study, we sought to determine the source of chitin in the symbiotic organ. We used a commercially available chitin-binding protein (CBP) conjugated to fluorescein to label the polymeric chitin in host tissues. Confocal microscopy revealed that the only cells in contact with the symbionts that labeled with the probe were the macrophage-like hemocytes, which traffic into the light-organ crypts where the bacteria reside. Labeling of extracted hemocytes by CBP was markedly decreased following treatment with purified chitinase, providing further evidence that the labeled molecule is polymeric chitin. Further, CBP-positive areas co-localized with both a halide peroxidase antibody and Lysotracker, a lysosomal marker, suggesting that the chitin-like biomolecule occurs in the lysosome or acidic vacuoles. Reverse transcriptase polymerase chain reaction (PCR) of hemocytes revealed mRNA coding for a chitin synthase, suggesting that the hemocytes synthesize chitin de novo. Finally, upon surveying blood cells from other invertebrate species, we observed CBP-positive regions in all granular blood cells examined, suggesting that this feature is a shared character among the invertebrates; the vertebrate blood cells that we sampled did not label with CBP. Although the function of the chitin-like material remains undetermined, its presence and subcellular location in invertebrate hemocytes suggests a conserved role for this polysaccharide in the immune system of diverse animals.
A hypothalamic projection to the turtle red nucleus: an anterograde and retrograde tracing study.

It is well known that the reptilian red nucleus lacks a descending motor cortical input to the red nucleus, but has a well-developed cerebellar input. The present study was undertaken to determine whether there is a descending rubral input that originates from the hypothalamus. Using an in vitro preparation from the turtle, injections of neurobiotin into the red nucleus resulted in retrograde labeling of neurons in the suprapeduncular nucleus of the hypothalamus. Injections of either neurobiotin or fluorescein dextran into the suprapenduncular nucleus resulted in anterograde labeling of axons and terminal boutons in the red nucleus. The majority of these terminations appeared to lie in the medial part of the red nucleus. These data have implications for the potential control of the somatic motor system of reptiles by limbic system inputs.
Pathophysiology of immune thrombocytopenic purpura

In 1951, the young hematologist in training, Dr. William Harrington, infused himself with plasma from a patient with immune thrombocytopenic purpura (ITP). He rapidly developed severe, but transient, thrombocytopenia and was at risk for serious hemorrhage. Thus, the humoral autoimmune cause of ITP was established. Since 1953, when Dr. Harrington's in vivo studies ended, in vitro investigations have aimed to determine the molecular and cellular details of immune-mediated platelet destruction.
Cardiovascular outcomes in the African American Study of Kidney Disease and Hypertension (AASK) Trial.

Background: Patients with chronic kidney disease are at increased risk for cardiovascular (CV) events. Methods: We randomly assigned 1,094 African Americans with hypertensive nephrosclerosis (glomerular filtration rate [GFR], 20 to 65 mL/min/1.73 m2 [0.33 to 1.08 mL/s]) to initial antihypertensive treatment with either: (1) a β-blocker, metoprolol; (2) an angiotensin-converting enzyme inhibitor, ramipril; or (3) a dihydropyridine calcium channel blocker, amlodipine, and either a usual–blood pressure (BP) or low-BP treatment goal. Using a design powered to detect renal outcome differences, we compared the effect of treatment on the CV event rate (cardiac death, myocardial infarction, stroke, and heart failure) during a mean follow-up period of 4.1 years and determined baseline factors that predict CV outcomes. Results: Thirty-one patients died of CV disease (0.7%/patient-year), and 149 patients experienced at least 1 CV outcome (3.3%/patient-year). Overall, 202 CV events (4.5%/patient-year) occurred. The CV outcome rate was not related significantly to randomized interventions. In multivariable analyses, 7 baseline risk factors remained independently associated with increased risk for the CV composite outcome after controlling for age, sex, baseline GFR, and baseline proteinuria group: pulse pressure, duration of hypertension, abnormal electrocardiogram result, non–high-density lipoprotein cholesterol level, serum urea nitrogen level, urine protein-creatinine ratio, urine sodium-potassium ratio, and annual income less than $15,000. Conclusion: Neither randomized class of antihypertensive therapy nor BP level had a significant effect on the occurrence of CV events, possibly because of limited power. However, this analysis identifies unique and potentially modifiable CV risk factors in this high-risk cohort.
Goal Instability in Relation to Career Thoughts, Decision State, and Performance in a Career Course:

Goal instability and its relation to career thoughts, decision state, and performance in an undergraduate career course in a large university were investigated in this study. Participants completed six instruments measuring the nature of goals, career thinking, occupational decision making, satisfaction with career choice, tension associated with career decisions, and a performance contract of course activities to be completed for a grade. Bivariate correlations and multiple regression analyses indicated that the degree of goal instability was directly related to negative career thoughts, dissatisfaction with career choice, career tension, and inversely related to classroom performance. Results of the analyses suggested that goal instability may serve as an initial global screening measure of readiness for career exploration in a classroom environment. The use of supplementary readiness measures is discussed.
Specific interactions for ab initio folding of protein terminal regions with secondary structures

Proteins fold into unique three-dimensional structures by specific, orientation-dependent interactions between amino acid residues. Here, we extract orientation-dependent interactions from protein structures by treating each polar atom as a dipole with a direction. The resulting statistical energy function successfully refolds 13 out of 16 fully unfolded secondary-structure terminal regions of 10-23 amino acid residues in 15 small proteins. Dissecting the orientation-dependent energy function reveals that the orientation preference between hydrogen-bonded atoms is not enough to account for the structural specificity of proteins. The result has significant implications on the theoretical and experimental searches for specific interactions involved in protein folding and molecular recognition between proteins and other biologically active molecules.
Memory load and latency in recognition of pictures.

Color photographs of common scenes were used as memory and test items in two memory search experiments. Memory load varied from 2 to 24 items in one experiment and from 4 to 64 in the other. Latency of classification of test items increased with memory load. The increase is verb’ close to linear for loads up to six items, but for the full range of memory loads, it is negatively accelerated and approximately logarithmic. Sternberg’s (1966, 1969) serial theory of memory search, which predicts linear functions, holds for small memory loads of pictures. If serial search takes place for large memory loads, the speed of search must be faster than for small loads. It is also possible that items in memory loads of all sizes are accessed by a single process that generates a negatively accelerated relation between size of load and latency.
Architecture-based approach to reliability assessment of software systems

Abstract With the growing emphasis on reuse, software development process moves toward component-based software design. As a result, there is a need for modeling approaches that are capable of considering the architecture of the software and estimating the reliability by taking into account the interactions between the components, the utilization of the components, and the reliabilities of the components and of their interfaces with other components. This paper details the state of the architecture-based approach to reliability assessment of component based software and describes how it can be used to examine software behavior right from the design stage to implementation and final deployment. First, the common requirements of the architecture-based models are identified and the classification is proposed. Then, the key models in each class are described in detail and the relation among them is discussed. A critical analysis of underlying assumptions, limitations and applicability of these models is provided which should be helpful in determining the directions for future research.
A Research Note on Class Awareness and Class Identification and the Hollingshead Index of Social Position

(1971). A Research Note on Class Awareness and Class Identification and the Hollingshead Index of Social Position. The Sociological Quarterly: Vol. 12, No. 1, pp. 90-99.
Capsular stroke in congenital complete heart block.

A normally developed 6 year old boy with congenital complete heart block presented with right hemiparesis of one month duration. The ventricular pacemaker which was implanted at two months of age had not been functioning for four years and was not replaced because there was no history of syncope, dizziness, or decreasing exercise tolerance even though the ventricular rate was 54 beats per minute. Computerized tomography revealed an infarct in the left internal capsule. Stokes-Adams attacks have been reported as a complication in children with congenital heart block but cerebrovascular accidents as in this patient are unusual (1, 5, 6, 9).
Interactions between resting-state and task-evoked brain activity suggest a different approach to fMRI analysis.

The most widely used analytic approach in functional magnetic resonance imaging (fMRI) research is the general linear model (GLM). This approach is based on the idea that brain regions involved in performing a task can be discovered by subtracting the activity measured during task performance from
Presentation of HLA Class I-Derived Peptides: Potential Involvement in Allorecognition and HLA-B27-Associated Arthritis

Some 25 years ago, when purified HLA class I allotypes were first being analyzed, of major concern was that the papain used for solubilization might produce a mess of proteolytic fragments that would prove impossible to separate and sequence. Those fears proved unfounded (Parham et al. 1975), and the homogeneity of the preparations was sufficient to allow crystallization and determination of the three-dimensional structure (Bjorkman et al. 1987). Ironically the least ordered region of the electron density map provoked the most interest because it gave a first view of the diverse peptides bound by an MHC molecule. With this image a second chapter of HLA class I biochemistry began, its charge to determine the structures of bound peptides and their influence on the immune system. The extraordinary polymorphism of HLA class I heavy chains now seems quite manageable compared to the vast complexity of the peptides, and our present ignorance as to which ones are important for health and disease. The comparative weakness of most HLA class I associations with disease has made HLA-B27 an especially favored target for investigation, and more is known of the structure and peptide-presenting function of HLA-B27 than for any other HLA-B allotype (Lopez de Castro 1994). Much of this information relates to the native HLA-B27 molecule and has been collected in the belief that disease is a direct consequence of its antigen-presenting function. If one subscribes to the relevance of the transgenic rodent models, this position has almost become untenable. For rats and mice 'non-functional' forms of HLA-B27 are the agents of disease, raising the possibility that B27-associated arthritis is induced by HLA class II presentation of a B27-derived peptide, a variant of the mechanism advanced for the classical HLA class II-associated diseases: type 1 diabetes, multiple sclerosis and rheumatoid arthritis (Gregersen et al. 1987, Roudier et al. 1989, Cucca & Todd 1996, Hall & Bowness 1996). Such speculation invites the obvious question as to whether other diseases associated with HLA class I and chronic inflammation, HLA-C and psoriasis for example (Tiilikainen et al. 1980, Yanagisawa et al. 1995), result from class II presentation of class I peptides.
Domination dot-critical graphs

A graph G is dot-critical if contracting any edge decreases the domination number. It is totally dot-critical if identifying any two vertices decreases the domination number. We show that the totally dot-critical graphs essentially include the much-studied domination vertex-critical and edge-critical graphs as special cases. We investigate these properties, and provide a characterization of dot-critical and totally dot-critical graphs with domination number 2. We also consider the question of when a dot-critical graph contains a critical vertex.
Light scattering determinations of band offsets in semiconductor heterostructures

Inelastic light scattering is used to determine the band offsets in semiconductor heterojunctions. The conduction-band discontinuity is obtained from energy level spacings measured in electronic light scattering spectra of photoexcited quantum-well heterostructures. The method is applied to GaAs-AlGaAs, GaSb-AlGaSb and InGaAs-GaAs heterojunctions. The light scattering determinations of band offsets are examined, and these results are compared with those obtained with more conventional methods. The impact of the light scattering results on chemical trends is considered, along with the influence of strain in the band-lineup problem. >
Some high-potential trithioether chelates of copper

Abstract The linear quadridentate ligand 1,8-bis(2′-quinolyl)-3,6-dithiaoctane and the three quinquedentate ligands 1,9-bis(2′-pyridyl)-2,5,8-trithianonane, 1,9-bis(6′-methyl-2′-pyridyl)-2,5,8-trithianonane and 1,11-bis(2′-quinolyl)-3,6,9-trithiaundecane have been prepared. The deep green-blue copper(II) chelates have been characterized by optical and ESR spectroscopy and cyclic voltammetry. The two pyridyl chelates have similar tetragonal coordination about the copper, with an equatorial N 2 S 2 donor set, plus the third thioether sulfur bound axially. The most marked consequence of the pyridine α-methylation is that the Cu 2+/+ reduction potential is raised by about 200 mV; otherwise, the E 1 2 is consonant with previously advanced models for correlating redox potentials with ligand structural features. The pyridyl copper(II) complexes have been isolated as the tetrafluoroborate salts, whereas the quinolyl-copper(II) chelates are rather redox unstable, in association with even more positive Cu 2+/+ E 1 2 values, similar to that for dibromine reduction.
Biological Activity of Azadirachtin, Component of the Neem Tree Inhibiting Molting in the Face Fly, Musca autumnalis De Geer (Diptera: Muscidae)

The possible effects of azadirachtin, a component of the neem tree, Azadirachta indica A. Juss, in inhibiting molting in larvae of the face fly, Musca autumnalis DeGeer, were studied. Apart from delayed lethal action, effects on the pupation, adult emergence, and size of pupae or adults have been considered. A baseline exposure for 10 or 20min, ranging from 0.00001 to O.1μg/ml, was used, causing about 20 or 22.5 to 83.5 or 97.6% inhibition (inhibition of adult-concentration-probability lines). Doses required to inhibit the emergence of 50% of the adults (IC50) were found to be very low (0.0024 and 0.000039 μg/ml for the 10- and 20-min exposure times, respectively. The compound is characterized by its inhibition or prevention of formation of adult morphology. The effects on pupae (basedon proportion of undeveloped individuals) and adults (based on incomplete development, attachment to puparia, or inability to fly) were dose-dependent. The development from third larval instar to adult was completely inhibited by exposure to 0.1 μg/ml for 20 min(97.58%). No adults were obtained at doses of 1.10, 10.0, and 100.0 μg/ml. These concentrations caused about 100% mortality of larvae or developed pupae. Results showed a reduction in M. autumnalis size as a function of azadirachtin exposure. There seemed to bea direct relationship between the size of the resulting pupae or adult males and females, since treatment of larvae with 0.00001 to O.1μg/ml azadirachtin caused significant reductions in the pupal weights and dimensions, adult weights, wing dimensions, or interocular distances. Treatments with 0.00001 and 0.001 μg/ml resulted in an insignificant increase(0.8–1.6%) in female wing length/width. Concentrations 0.001, 0.01, and O.1μg/ml also did not significantly affect the wing dimensions of females.
Neighborhood Economic Development Effects of the Earned Income Tax Credit in Los Angeles Poor Places and Policies for the Working Poor

This paper explores the effect of the Earned Income Tax Credit (EITC) on poor neighborhoods of Los Angeles during the late 1990s. To date, few analyses have empirically examined the impact of people-based policies on the economies of poor neighborhoods. The paper first documents the magnitude of this individual wage subsidy in Los Angeles as an unrecognized investment in poor neighborhoods on par with place-based policies such as Enterprise Zones. The paper then uses IRS and Economic Census data by ZIP Code to test whether increased EITC income has an effect on the neighborhood retail job base. Findings suggest an independent correlation between EITC investments and retail job gain. The conclusion uses these results to suggest better policy coordination and recommend four productive areas for future research.
Children and the global tuberculosis situation

The current global strategy for control of tuberculosis, Directly Observed Treatment, Short-course (DOTS) focuses, as a priority, on the management of patients with sputum smear positive tuberculosis. As tuberculosis in children is rarely sputum smear positive, this has led many to believe that children are not important in tuberculosis control. This is a misconception. The ultimate goal of tuberculosis services should be the eradication of Mycobacterium tuberculosis. To date, only diseases for which effective vaccines are available have been eradicated. Vaccination aims to protect the population (and especially vulnerable groups, such as children) from the disease against which it is applied. Presently, there is no vaccine able to prevent infection with Mycobacterium tuberculosis. Protection against infection must be achieved in other ways. Thus, early identification and successful treatment of the most infectious cases of tuberculosis has become the focus of attempts and is presently the most effective means to protect children from infection with M. tuberculosis. This is the theory; does it really work? Evidence put forward to support this position has come primarily from industrialised countries where tuberculous infection was already on the decline before any substantial public health activities had been instituted. What of the situation in low income countries where the highest proportion of the tuberculosis patients live at the present time? There is very little evidence available to address this question. The most convincing information published to date comes from the Beijing Municipality of China where the DOTS strategy has been implemented since 1978. Progressive expansion of the strategy occurred over the first five years after which a very high proportion of all tuberculosis patients were managed by this means. The major impact was to progressively and rapidly reduce the prevalence of tuberculosis in the community. The incidence was only more slowly diminished over the same period, primarily because cases continued to arise from the large proportion of the population previously infected. Over the same period, tuberculous meningitis virtually disappeared and the prevalence of tuberculous infection declined to very low levels. This appears to confirm the impact of efficient management of adult tuberculosis patients as a means to protect children from infection. This, while effective, clearly is not sufficient. Every effort is required to develop an effective vaccine that is capable to preventing infection in children. Only then will the disease be eradicated.
Dual-beam interferometer for the accurate determination of surface-wave velocity

A novel dual-beam interferometer has been designed and constructed that enables two beams from a He–Ne laser to probe remotely the surface of a material. The separation of the two He–Ne beams is adjustable in the ∼15-to-∼40-mm range with a spatial resolution of 2 μm. Surface-acoustic-wave measurements have been performed with two different probe separations so that the travel time for the surface waves over a known distance can be determined accurately. With the aid of autocorrelation algorithms, the Rayleigh pulse velocity on 7075-T651 aluminum has been measured to be 2888 ± 4 m/s. The current precision of the system is limited mainly by the 10-ns sampling rate of the digital oscilloscope used. Rayleigh pulse interactions with a surface-breaking slot, machined to a nominal depth of 0.5 mm, have also been examined and the depth estimated ultrasonically to be 0.49 ± 0.02 mm. The system may also provide a technique for direct quantitative studies of surface-wave attenuation.
Breath ethane : a specific indicator of free-radical-mediated lipid peroxidation following reperfusion of the ischemic liver

A major component of the organ injury mediated by toxic oxidants, such as seen following reperfusion of the ischemic liver, is due to the peroxidation of polyunsaturated fatty acids, especially of cell membranes. We utilized the measurement of exhaled breath ethane, a metabolic product unique to oxidant-mediated lipid peroxidation, as a noninvasive indicator of this process in swine liver subjected to warm ischemia/reperfusion. Under rigorously controlled anesthesia conditions, pig livers were subjected to 2 h of warm total ischemia, followed by reperfusion in situ. Expired air was collected and its ethane content quantitated by a novel gas chromatographic technique. The time course of breath ethane generation correlated closely with the appearance of hepatocellular injury as measured by impairment of Factor VII generation and other measures of liver integrity. Moreover, the administration of the specific superoxide free radical scavenger, superoxide dismutase (SOD), significantly attenuated both the elaboration of ethane and the hepatocellular injury. These findings not only provide confirmation of the previously reported link between hepatocellular injury by free radicals generated at reperfusion, but also establish the use of expired breath ethane analysis as a sensitive, specific, and noninvasive indicator of the injury process in real time.
Working memory capacity for spoken sentences decreases with adult ageing: Recall of fewer but not smaller chunks in older adults

Previous studies show that older adults have poorer immediate recall for language but the reason is unknown. Older adults may recall fewer chunks from working memory, or may have difficulty binding words together to form multi-unit chunks. We examined these two hypotheses by presenting four types of spoken sentences for immediate free recall, differing in the number and length of chunks per trial: four short, simple sentences; eight such sentences; four compound sentences, each incorporating two meaningful, short sentences; and four random word lists, each under a sentence-like intonation. Older adults recalled words from (accessed) fewer clauses than young adults, but there was no ageing deficit in the degree of completion of clauses that were accessed. An age-related decline in working memory capacity measured in chunks appears to account for deficits in memory for spoken language.
The phantom cover of a module

Abstract A morphism f : M → N of left R-modules is a phantom morphism if for any morphism g : A → M , with A finitely presented, the composition fg factors through a projective module. Equivalently, Tor 1 ( X , f ) = 0 for every right R-module X. It is proved that every R-module possesses a phantom cover, whose kernel is pure injective. If mod - R is the category of finitely presented right R-modules modulo projectives, then the association M ↦ Tor 1 ( − , M ) is a functor from the category of left R-modules to that of the flat functors on mod - R . The phantom cover is used to characterize when this functor is faithful or full. It is faithful if and only if the flat cover of every module has a pure injective kernel; this is equivalent to the flat cover being the phantom cover. The question of fullness is only reasonable when the functor is restricted to the subcategory of cotorsion modules. This restriction is full if and only if every phantom cover of a cotorsion module is pure injective.
The Origin and Significance of Hyperplastic Hepatocellular Islands and Nodules in Hepatic Carcinogenesis

Results of many studies, summarized in this review, support the hypothesis that carcinogen-induced hepatocellular carcinomas develop from phenotypically-altered hyperplastic hepatocellular nodules; these in turn apparently arise from smaller focal collections of hyperplastic cells referred to as hepatocellular islands. The very recent recognition that phenobarbital, when administered after carcinogens, fosters the outgrowth of hepatocellular islands and carcinomas, now provides the means for studying stages of initiation and promotion in hep-atocarcinogenesis. In addition, the recognition that enzymatic alterations, particularly the acquisition of canalicular gamma glutamyl transpeptidase activity, loss of ATP'ase activity, and loss of glucose-6-phosphatase activity that characterize many islands, have been particularly useful for measuring and evaluating the growth kinetics and heterogeneity of the islands. Evidence is presented that periportal gamma glutamyl transpeptidase positive hepatocytes are consi...
Grassland Management Activity Data: Current Sources and Future Needs

Estimates of potential and actual C sequestration require areal information about various types of management activities. Forest surveys, land use data, and agricultural statistics contribute information enabling calculation of the impacts of current and historical land management on C sequestration in biomass (in forests) or in soil (in agricultural systems). Unfortunately little information exists on the distribution of various management activities that can impact soil C content in grassland systems. Limited information of this type restricts our ability to carry out bottom-up estimates of the current C balance of grasslands or to assess the potential for grasslands to act as C sinks with changes in management. Here we review currently available information about grassland management, how that information could be related to information about the impacts of management on soil C stocks, information that may be available in the future, and needs that remain to be filled before in-depth assessments may be carried out. We also evaluate constraints induced by variability in information sources within and between countries. It is readily apparent that activity data for grassland management is collected less frequently and on a coarser scale than data for forest or agricultural inventories and that grassland activity data cannot be directly translated into IPCC-type factors as is done for IPCC inventories of agricultural soils. However, those management data that are available can serve to delineate broad-scale differences in management activities within regions in which soil C is likely to change in response to changes in management. This, coupled with the distinct possibility of more intensive surveys planned in the future, may enable more accurate assessments of grassland C dynamics with higher resolution both spatially and in the number management activities.
Steric and Electronic Influences on the Torsional Energy Landscape of Retinal

We have performed quantum mechanical calculations for retinal model compounds to establish the rotational energy barriers for the C5-, C9-, and C13-methyl groups known to play an essential role in rhodopsin activation. Intraretinal steric interactions as well as electronic effects lower the rotational barriers of both the C9- and C13-methyl groups, consistent with experimental 2H NMR data. Each retinal methyl group has a unique rotational behavior which must be treated individually. These results are highly relevant for the parameterization of molecular mechanics force fields which form the basis of molecular dynamics simulations of retinal proteins such as rhodopsin.
Stranski-Krastanov growth of Ag on Au(111) electrodes.

We present results obtained by in situ scannning tunneling microscopy which show the morphological details of the transition from layer by layer growth to three-dimensional island growth during electrodeposition. Two epitaxial layers of Ag are sequentially formed prior to the heterogeneous nucleation of three-dimensional Ag crystallites which preferentially develop on steps. The 3D growth initiates when 2D protrusions growing on the completed second adlayer achieve a critical dimension of order 20--50 nm. Our observations and analysis indicate that the growth transition may be kinetically determined by adatom migration over descending steps.
Determination of nickel(II) as the nickel dimethylglyoxime complex using colorimetric solid phase extraction

Abstract Colorimetric solid phase extraction (C-SPE) is an analytical technique in which analytes in water samples are extracted onto a solid adsorbent matrix impregnated with a colorimetric reagent and then quantified directly on the adsorbent surface using diffuse reflectance spectroscopy. This paper presents a further development in C-SPE. In this case, the reagent employed to detect the analyte is not impregnated on the extraction medium. Instead, the reagent is weakly immobilized on a solid support (i.e., filter paper) and released into the sample as it flows through the support. The reagent complexes the analyte in solution, forming a highly colored precipitate that is collected on the surface of an extraction membrane. The concentration of analyte is determined using the Kubelka–Munk function calculated from the diffuse reflectance spectrum of the precipitate on the membrane surface. This precipitation–spectrophotometric platform is extensively evaluated by determining nickel(II) using dimethylglyoxime (DMG) as the precipitating reagent. The ability to optimize reaction conditions with immobilized reagents by in-line buffering is also demonstrated. Specifically, borax buffer was utilized to adjust the pH of nickel(II) samples prepared in deionized water. This combination of immobilized buffer and reagent allows C-SPE to operate in a solid-phase mode in which all the reagents requisite for optimal analyte determination are immobilized on solid supports. Using this method, nickel(II) was determined in a single processing step over the concentration range 0.50–5.0 ppm in ∼40 s with 1.0 ml sample volumes.
An algorithm for distributed computation of FFTs

Abstract A fault tolerant single-instruction multiple-data (SIMD) algorithm is presented for distributed computation by parallel processors of one-dimensional radix-2 Fast Fourier Transforms (FFTs). The algorithm can be used for any number of nodal processors equal to a power of 2, including the special case of a single processor. The proposed algorithm requires only a slight extension of a customary single processor FFT algorithm. Relationships are derived for generating the appropriate FFT weighting factors in the distributed processors and simple strategies are presented for managing the necessary data transfers among processors and for accessing data in the memories. The detailed operation of the distributed algorithm is illustrated through examples.
Inter-Organizational-Trust in Business to Business E-Commerce: A Case Study in Customs Clearance

This study seeks to understand inter-organizational-trust as an antecedent factor in adoption of and participation in e-commerce. Exploratory research together with a literature review paved the way to the development of a conceptual model. The model was tested via four case studies consisting of a large public sector organization and three small-medium enterprises (SMEs) involved in customs clearance. SMEs included an Internet service provider, a customs broker (agent), and an importer. Data was collected via indepth interviews, discussions with key personnel, and from existing documents. The findings strongly indicate that inter-organizational trust is important for e-commerce participation, as organizations need to cooperate, collaborate, and communicate timely and relevant information in order to facilitate e-commerce. This entails not only technological proficiencies, but also trust between trading parties, so that business transactions are sent and received in an orderly fashion.
A coaxial microwave applicator for transurethral hyperthermia of the prostate

Benign prostatic hyperplasia (BPH) is a common disease of elderly men. The current definitive treatment for urinary obstruction caused by this disease is surgery (transurethral resection of the prostate, or TURP). Recent evidence suggests that hyperthermia may be a useful nonsurgical alternative for treatment of symptomatic BPH. A transurethral microwave applicator has been designed around a Foley catheter for delivery of local hyperthermia to the prostate. The Foley balloon is used to maintain the antenna position within the prostatic urethra. The Foley catheter also features an antenna choke to confine power deposition to the intended region. The antenna is a coaxial dipole designed to operate at 915 MHz. Qualitative and quantitative specific absorption rate (SAR) patterns are shown for this antenna. In vivo experiments in dog prostate demonstrate that temperatures > 42 degrees C can be obtained > 1 cm away from the catheter, while maintaining a maximum urethral temperature of 47 degrees C to 48 degrees C. Histology obtained acutely after the hyperthermia treatments showed minimal damage to the periurethral tissues. We conclude from these studies that this microwave applicator is capable of providing local hyperthermia to the prostatic tissues with a predictable and well-circumscribed thermal distribution.
Effective Public Service Advertisements to Attract Volunteers for the Special Olympics: An Elaboration Likelihood Perspective

As many sport organisations are frequently in great need of volunteers, it is important for sport marketers to develop effective public service advertisements (PSAs) to attract volunteers. The purpose of this study was to expand and test a theory of persuasion for PSAs designed to lead people to help with the Special Olympics. More specifically, this study was designed to broaden the Elaboration Likelihood Model (ELM) by incorporating a newly added personality variable, empathic tendency, and to show how this variable affects audiences’ information processing of PSAs. In order to test the ELM, a three-way, 2 (empathy: high v low) x 2 (argument quality: strong v weak) x 2 (peripheral cue: celebrity v non-celebrity status) factorial design was used. A total of 102 male and 119 female students participated ( n = 221). The results indicated that both high empathy subjects and low empathy subjects were motivated to process the persuasive messages, suggesting that both groups followed the central route to processing. Involvement was found to significantly influence the argument processing of low empathy subjects. Celebrity status did not serve as a peripheral cue in this study.
Coding specificity of Escherichia coli leucine transfer ribonucleic acids and effect of bacteriophage T2 infection

Leucyl-transfer ribonucleic acid from Escherichia coli with and without phage T2 infection was fractionated into five components (Leu1 to Leu5) by reversed-phase chromatography. The codon specificity of each component was studied by ribosomal binding and leucine incorporation. The most probable assignments for uninfected E. coli leucine tRNA are: Leu1, CUG; Leu2, CUU, CUC; Leu3, CUA, CUG; Leu4, UUG; Leu5, UUG. The five components of E. coli leucine tRNA eight minutes after T2 infection showed codon specificity essentially similar to their E. coli counterparts, although the relative amount of Leu1 decreased and that of Leu5 increased, as previously shown. There was, however, a quantitative difference in the UUG-stimulated binding of T2 Leu5 to ribosomes. Moreover, T2 Leu5 is heterogeneous, including a component or components which respond to UUG. Complete codon assignment of T2 Leu5 cannot be made at the present time.
Discrete Frequency Models: A New Approach to Temporal Analysis

Forced vibration responses of nonlinear systems contain harmonics of the excitation frequency. These harmonics are either directly forced or are subharmonic, superharmonic, or combination resonances. Nonlinear responses of this type have been modeled historically using continuous time, discrete time, and continuous frequency models. A new approach to dynamic systems analysis is introduced here that uses difference equations in the discrete frequency domain to describe the evolution of forced, single degree of freedom, steady state vibration responses in frequency instead of time. A variety of possible applications in nonlinear experimental structural vibrations are also discussed.
Memory strategies in children with learning disabilities

Abstract Memory strategies were examined among children, 7–13 years old, with diagnosed learning disabilities, in order to investigate whether they perform in appropriately active and efficient ways. The children were grouped at two age levels and administered tasks of serial recall and free recall. A strategy-training session was conducted on the second task. On the serial recall, neither age group showed evidence of rehearsal, in contrast to previous studies. On the free recall task, the younger children's performance was consistent with the mediation deficiency hypothesis, while the older children improved in sorting, clustering, and recall following training; i.e., they showed a typical production deficiency. There was support for considering this sample of learning disabled children as inactive learners, with potential developmental change. Serial recall improved with age, and the older children's production deficiences in free recall appeared to be ameliorated with training in organizational strategies.
Energetic equivalence in a soil arthropod community from an aspen–conifer forest

Summary We evaluated the energetic equivalence rule for a community of litter and soil arthropods from an aspen–conifer forest in the Sangre de Cristo Mountains of southwestern North America. We found that across taxa and within trophic groups the number of arthropods per square meter, N , scaled with body mass, M , raised to the −0.78 power and that primary and secondary decomposers, combined, were 8.51 times more abundant than carnivores. Given that arthropod abundance scaled as M −0.78 and that soil invertebrate metabolic rates, Q , scale approximately as M 0.78 , it appears that within coarse trophic groups at our study site, energy use by soil arthropod populations, Q tot ∝ NQ , is approximately independent of body size, Q tot ∝ M −0.78 M 0.78 ∝ M 0 .
For-profit entities and continuing education: a nursing perspective.

H ealth care: providers need continuing education; in some states or jurisdictions and for some specialty certifications, each provider must earn a specified number of hours of continuing educat:ion per licensure period. For several years, corporate sponsors from the medical device and pharmaceutical industries have provided continuing education for physicians, including free transportation and lodging in resort locales.’ Recently, however, organized medicine has been forced to address the ethical issues surrounding subsidized continuing education and other types of support from biomedical industry.