cssi/SciSciGPT-SciSciNet huggingface dataset:
A new class of heuristic algorithms for weighted perfect matching

The minimum-weight perfect matching problem for complete graphs of n vertices with edge weights satisfying the triangle inequality is considered. For each nonnegative integer k ≤ log3n, and for any perfect matching algorithm that runs in t(n) time and has an error bound of ƒ(n) times the optimal weight, an O(max{n2, t(3-kn)})-time heuristic algorithm with an error bound of (7/3)k(1 + ƒ(3 kn)) - 1 is given. By the selection of k as appropriate functions of n, heuristics that have better running times and/or error bounds than existing ones are derived.
Pseudomonas aeruginosa potentiates the lethal effect of intestinal ischemia-reperfusion injury: the role of in vivo virulence activation.

Introduction Experimental models of intestinal ischemia reperfusion (IR) injury are invariably performed in mice harboring their normal commensal flora, even though multiple intestinal IR events occur in humans during prolonged intensive care confinement when they are colonized by a highly pathogenic hospital flora. The aims of this study were to determine if the presence of the human pathogen P. aeruginosa in the distal intestine potentiates the lethality of mice exposed to intestinal IR and to determine what role if any in vivo virulence activation plays in the observed mortality.
The influence of 2-chloroadenosine on potassium-evoked and neurally-evoked acetylcholine secretion from normal or from latent active zones in the frog

1 It has been suggested that adenosine receptor agonists do not impair K-dependent acetylcholine (ACh) secretion at motor nerve endings. If true, this result would be discordant with the conventional theories of adenosine action at the neuromuscular junction. It was thus decided to examine the effect of 2-chloroadenosine on quantal ACh release evoked by different K concentrations at frog motor nerve endings. 2 Quantal ACh release evoked by mild increases in the extracellular K concentration (from 2 mm to 6–11 mm) was inhibited by 2-chloroadenosine (10 μm) in a manner similar to the inhibition of neurally-evoked ACh release. 3 ACh secretion evoked by prolonged exposure to 20 mm K Ringer was also inhibited by adenosine derivatives. Under these conditions, alterations in the structure of the secreting active zones have been reported whereby the original release sites now release only a small proportion of the total quantal ACh output. 4 Preparations were bathed for several hours with Ca-free Ringer containing Mg to examine further the importance of intact active zones on inhibition produced by adenosine receptor agonists. This procedure has been reported to produce latent sites of ACh secretion and persistent derangement of the active zones. Shortly after this treatment, neurally-evoked ACh release in normal Ringer solution was found to be inhibited by 2-chloroadenosine (1–5 μm) or adenosine (50 μm). 5 The results suggest that (a) K-evoked ACh release is inhibited by adenosine derivatives even when quantal secretion occurs outside the original active zone and that (b) the cytoskeletal or membrane structures which maintain the structural integrity and lateral regularity of the active zones are not the target sites for inhibition by adenosine derivatives.
Chemical Compatibility of Polymers

In many industries, metals, such as carbon steel, stainless steel, nickel-base alloys and other alloys, are often used for primary process equipment, such as tanks, piping, valves, and pumps. However, most facilities and equipment cannot practically be made solely from metals because of either cost or functional considerations. Polymeric materials (plastics, elastomers, composites, etc.) are therefore commonly employed to handle chemicals, whether for bulk storage and transfer (tanks, piping, hoses, and tubing), sealing (gaskets, O-rings, and valve seats), corrosion protection (coatings, tank linings, and secondary containment), labware, safety equipment, and many other applications. However, every polymer is not resistant to all chemicals or even to a single chemical in all concentrations or at all temperatures. Even Teflon PTFE (polytetrafluoroethylene), an extremely inert fluoropolymer, can be affected by some chemicals. Polymers are susceptible to many possible degradation mechanisms in chemical environments, including oxidation, dissolution, hydrolysis, absorption/ swelling, plasticization, crazing, and environmental stress cracking (ESC). Strong oxidizing agents, such as nitric acid, are particularly aggressive and most polymers are susceptible to oxidation to some degree. Solvents, particularly halogenated types, are also aggressive. Fluoropolymers such as PTFE, FEP (fluorinated ethylene‐propylene), and PFA (perfluoroalkoxy) types are the most resistant, with ETFE (ethylene‐tetrafluoroethylene), ECTFE (ethylene‐chlorotrifluoroethylene), and polyvinylidene fluoride (PVDF) also used within concentration and temperature limits. HDPE (high-density polyethylene), LDPE (low-density polyethylene), polypropylene (PP), and other polyolefin plastics are also resistant to many chemicals, though these are less resistant than fluoroplastics. HDPE can be sensitive to ESC (ESC) in certain environments, with specific tests designed for evaluating environmental stress-cracking resistance (ESCR). Failures due to ESC can be catastrophic
Average atomic number of heterogeneous mixtures from the ratio of gamma to fast-neutron attenuation

Abstract The attenuation of a continuous spectrum of fast neutrons by each pixel in a luggage image can be used to detect plastic explosives in the presence of other materials. The method involves deconvolution of the attenuations into elemental compositions of H, C, N, O and X, where X includes everything other than these elements. To improve discrimination, one can also measure the average atomic number, Z, of the mixture of materials in each pixel. We have measured attenuations, by single-element samples, of prompt γ-rays produced from bombardment of a thick Be target with 4.2 MeV deuterons. We report, in this regard, measured prompt γ-ray spectra, whose median energies indicate that associated γ attenuations are dominated by Compton scattering. Attenuations were measured subsequently for several thicknesses each of C, Al, Cu, Cd, Sn and Pb. We have also investigated the attenuation of the fast-neutron spectrum between 8.2 MeV and 5.5 MeV. We found that the ratio of γ-ray to neutron attenuation generally increases, albeit not linearly, with Z. We apply these results to examine the effective Z of heterogeneous mixtures of H 2 OC and CAl, and have begun to incorporate effective Z into explosives-detection algorithms.
A quantitative study of recency and frequency based web cache replacement strategies

There are many replacement strategies to consider when designing a web cache server. The most commonly known cache replacement strategies are Least Frequently Used (LFU) and Least Recently Used (LRU). Though comprehensive surveys exist, no known study has presented comparative performance measures of these strategies together. We will review and describe proxy cache replacement strategies based on the recency, frequency, and size attributes of web objects, and present two performance measures. Simulation results ranked by the two performance metrics, hit rate and byte hit rate, reveal strong inductions about current cache replacement strategies.
Hormonal modulation of interleukin-6, tumor necrosis factor and associated receptor secretion in postmenopausal women.

Hormone replacement therapy (HRT) reduces the risk for osteoporosis but transiently increases cardiovascular risk for some postmenopausal women. This study investigated the hypothesis that these risks are associated with HRT-induced changes in mononuclear cell secretion of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), and associated soluble receptors. Compared to the untreated condition (n=8), estrogen therapy (n=7) and estrogen+progestin therapy (n=7) both caused 2-fold elevations in TNF-α secretion. IL-6 secretion was increased (48%, P=0.04) only by estrogen+progestin therapy. Although soluble receptor secretion was not different among groups, soluble TNF receptor type I and IL-6 receptor secretion were inversely related to plasma follicle stimulating hormone (P<0.05). Both therapies reduced plasma osteocalcin (a marker for osteoporosis) by ∼50% (P<0.002). Plasma C-reactive protein (CRP, a marker for cardiovascular risk) was 3-fold higher in women receiving only estrogen, compared to untreated women (P=0.01), and twice as high as those receiving estrogen+ progestin (P=0.045). Simple linear relationships were not observed between cytokine secretion and these markers, but a significant HRT/TNF-α interaction with osteocalcin (P=0.022) and an HRT/IL-6 interaction with CRP (P =0.016) indicated more complex relationships between hormone replacement, cytokine activity, and health risks associated with menopause.
Polymer-Stabilized Reflective Cholesteric Displays: Effects of Chiral Polymer Networks on Reflectance Properties

A white reflecting polymer-stabilized cholesteric textured liquid-crystal cell was created by incorporation of chiral methacrylate polymer networks. The position and stereochemical configuration of...
Dynamics of ring current ions as obtained from IMAGE HENA and MENA ENA images

[1] Ion distributions from three storms in the year 2000 have been obtained from HENA and MENA ENA images at 27–39 keV and 5–12 keV, respectively. The observed motion of the ring current is compared with calculations of expected radial and angular drift speeds made using a combination of the Tsyganenko 89 magnetic field model and the Weimer 2001 electric field model. In one case between 1000 and 1100 UT on 10 June 2000 that had already been reported, the westward drift of the 33 keV ions is as expected. Comparisons with speeds inferred from the motion of peaks in the ion distributions, however, often did not agree with the model predictions. Examination of the predicted paths showed that the ions are expected to experience significant energy changes as they drift so that they quickly move out of the observed energy channel. Thus we are able to conclude that the observed motion is consistent with equatorial electric fields in the inner magnetosphere of a few tenths of a mV/m on 10 June 2000, several mV/m on 12 August 2000, and ≤1 mV/m on 4 October 2000 as predicted. Other interesting observations include (1) the suggestion of a two step injection process during the main phase of the 4 October 2000 storm, (2) the unexplained disappearance of the 33 keV protons when their drift motion brings them to noon in the recovery phase of the 10 June 2000 storm, (3) the apparent subtle changes in the electric potential pattern in the equator early in the 4 October 2000 storm, and (4) the energy dependence of the spatial source of the injected particles in the plasma sheet during the strong storm on 12 August 2000.
Axisymmetric buckling of hollow spheres and hemispheres

Abstract : A nonlinear thin shell theory is derived for the axisymmetric buckling of spherical shells subjected to either a pressure or a centrally directed surface load. The theory is reduced to a boundary value problem for a system of four first order ordinary differential equations. Numerical solutions of this boundary value problem are obtained by the shooting and parallel shooting methods. An extensive numerical study is made of the nonlinear deformations of the shells. We find for example, that all solution branches that bifurcate from the eigenvalues of the linearized buckling theory are connected to each other by means of intermediate branches. Some implications of the numerical results concerning the buckling of spherical shells are discussed. (Author)
US Spending On Complementary And Alternative Medicine During 2002–08 Plateaued, Suggesting Role In Reformed Health System

Complementary and alternative medicine services in the United States are an approximately $9 billion market each year, equal to 3 percent of national ambulatory health care expenditures. Unlike con...
Neurological knowledge and complex behaviors

Some scholars believe thot Cognitive Science is the attempt to achieve in artificial systems what has already been achieved in the brain. Others, by contrast, argue that the study of ideal adaptive mechanisms could go on without reference to the brain. The author points out that the brain may not be the ideal cognitive device because of biological limitotions on its capacity. Although it may not be ideal, it is still of major interest to cognitive scientists because of the great interest in the human mind, and, in addition, because at this moment the brain is the most important single reservoir of odoptive mechanisms. The paper discusses several areas of neuroscience which are likely to shed light on mechanisms of adaptation. The study of simple nervous systems is likely to reveal important design principles of cognitive devices. The study of complex nervous systems will, of course, exert a major influence. The study of such systems leads to certain general principles concerning the neural circuits involved in complex odoptive behaviors: (1) There exist innate specialized systems for the learning of many specific behaviors that at first might appeor to be purely cultural. (2) There is no evidence for the existence of any all-purpose computer in the brain. (3) There are many surprising dissociations manifested by the specialized systems in the brain, e.g., a special system for recognition of faces as against other visual patterns. (4) The study of the nervous system enables one to formulate more precise mechanisms for the role of emotion in cognitive function.(5) Some human behoviors con probably be understood poorly or not at all if the neural substrate is not considered. (6) The cognitive systems designed for dealing with ottentionol processes may be among the most complex neural structures which underlie behavior. There are certain other properties of brains that should be kept in mind by the cognitive scientists who are studying human behovior: (1) Brains differ from each other in structure, and it is very likely that the strategy for the solution of certain problems differs from person to person. (2) The presence of certain innate cognitive strategies in the brain may prevent that organism from employing other strategies which might be optimal for other problems. (3) Any theory about a particular cognitive strategy will have implications as to the particular mode of breakdown that might be expected after brain lesions. The study of disordered function from brain disease may thus be a valuable way to test certain cognitive theories.
Big signals of Little Randall-Sundrum models

Abstract We examine signals at the Large Hadron Collider (LHC) of Kaluza–Klein modes, in volume-truncated “Little Randall–Sundrum” (LRS) models of flavor, characterized by 5D cutoff scales M 5 that are small compared to the 4D Planck mass M P ∼ 10 19 GeV . In particular, for the phenomenologically viable choice M 5 ∼ 10 4 TeV , the discovery of a 2 (3)-TeV “Little” Z ′ at the LHC requires about 1 (4) fb −1 at s = 10 (14) TeV, in the clean di-lepton channel . Our results highlight the possibility of probing interesting values of M 5 , starting with the early LHC data. With M 5 ∼ 10 4 TeV , discovering the second KK mode Z ″ , at about 4.3 TeV, requires O ( 100 ) fb − 1 at s = 14 TeV , providing a probe of the warped nature of the bulk that is encoded in the mass ratio of the first two KK modes, at design luminosity. By comparison, discovering a 3-TeV Z ′ of the Planck-weak hierarchy models (with M 5 ∼ M P ), in any channel , would require upwards of O ( 300 ) fb − 1 at s = 14 TeV . We also point out that discovery prospects markedly improve for Little KK gluons as well, but the challenging reconstruction of their t t ¯ decay products may hamper their early discovery.
Dynamic Shortest-Path Algorithm for Continuous Arc Travel Times: Implication for Traffic Incident Management

To achieve the desired computational speed, existing algorithms for time-dependent (or dynamic) shortest-path problems call for the unrealistic aggregation of travel time as multiples of a given time increment. While the time increment can be varied between, say, peak and off-peak periods, it still has its obvious limitation on granularity. An improved solution algorithm is proposed for the all-to-one or one-to-all time-dependent versions of the problem. The algorithms are solidly founded on Bellman's principle of optimality and apply to continuous or real-value arc travel times (rather than the current practice of discretetime specifications). The new algorithms are practical in computational speed, and they capture a more realistic metric for route choice. In this case, a relatively coarse time increment can be used throughout the analysis, yet it is compatible with any continuous or real-value arc travel times. To support these claims, computational results that consider various network sizes, densitie...
Fetal to Adult Stem Cell Transition: Knocking Sox17 off

What controls the inherent differences between fetal and adult hematopoietic stem cells (HSCs)? In this issue of Cell, Kim et al. (2007) demonstrate in mice that the endodermal transcription factor Sox17 is required for the maintenance of fetal and neonatal but not adult HSCs.
Studies of Platelet Adhesiveness with Reference to Platelet Age

In this study, autologous human platelets labelled with 31Cr were infused in healthy volunteers and their adhesiveness to glass was repeatedly measured during their survival in the circulation using the Salzman's technique. 51Cr-specific activity was determined seperately for the ‘adhesive’ and ‘non-adhesive’ platelets and expressed as a ratio of the two values. This ratio was found to be approximately 1 in all the conditions studied. The results indicated: (1) that platelet labelling in vitro with 51Cr did not alter platelet adhesiveness to glass, and (2) that aging of the platelets in the circulation was not associated with a change in their adhesiveness. Other experiments were done using platelets which had been damaged by a 24hour storage at 4°C. before infusion. The results demonstrated that although survival of these platelets was drastically reduced, their adhesive property to glass remained unchanged. It was concluded that a large ‘reservoir’ of adhesive property must exist in the platelets and that this is independent of the damage produced by cell aging in the circulation and by storage in vitro at 4°C.
A Dual Mode Nonlinear Interpolative Compressor For SAR Images

A dual mode nonlinear interpolative compressor is described which compresses synthetic aperture radar images. The compression algorithm takes advantage of (1) the strong contrast between the target and the background, (2) the small percentage of target area compared with the total SAR image. The algorithm operates in two modes, i.e., an exact data transmission mode and an interpolative mode. The image is first segmented into small sub-blocks. The compressor then selects one of two modes according to the pixel values inside the block. If any pixel inside the block is above a predetermined threshold all pixels in this block are transmitted. On the other hand, if all pixels inside the block are below the threshold only one pixel is transmitted. At the receiver a two dimensional interpolation is then conducted to estimate the entire pixels in the block. Under the stationary assumption of the background information a second order statistic of the SAR image is used to derive the interpolative scheme. The compressor not only offers a high degree of exact target recovery but also offers a good recovery of the background information. Computer simulation results indicate that a good quality reconstruction can be accomplished with 1.5 bits per pixel.© (1975) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Segmentation algorithm for objects with very low edge contrast

We present an algorithm for segmentation of objects with very low edge contrast, such as microcalcifications in mammogram images. Most methods used to segment microcalcifications have algorithmic aspects that could raise operational difficulties, such as thresholds or windows that must be selected manually, or parametric models of the data. The presented algorithm does not use any of these techniques and does not require that any parameters be set by a user. It builds upon an earlier algorithm presented, but is much faster and also applicable to a wider range of objects to be segmented. The algorithm’s approach is based on the extension of radial intensity profiles from a given seed point to the edge of the image. A first derivative analysis is used to find an edge point pixel along each directional intensity profile. These points are connected and the resulting object border is filled using a constrained dilatation operation to form a complete region. Results from the tested mammography images indicate that the segmented regions compare closely to those expected from visual inspection.
Effects of Listening Instructions on Attention to Manner and Content of Stutterers' Speech

The influence of instructions given to audiences on their listening reactions to the aspects of content and manner of a stutterer’s speech was studied. Sixty-seven students listened to a tape recor...
Fluoroscopically guided percutaneous pancreatography.

Definition of pancreatic ductal anatomy may be necessary both to help determine the exact etiology of an abnormality and to help in decisions of surgical management. Endoscopic retrograde cholangiopancreatography (ERCP) is the first method of choice but if unsuccessful, a fluoroscopically guided percutaneous study of the duct can be an excellent alternative in selected patients.
Locally recurrent rectal cancer : surgical strategy

Relapses after “curative resection” of rectal cancer may be localized and thus amenable to surgical treatment. The risk of relapse may be higher than previously believed depending on adequacy and length of follow-up, the diagnostic modalities used, and the number of autopsies performed. Technical refinements such as a distal margin >2 cm, radical pelvic lymphadenectomy, and high ligation of the inferior mesenteric artery at the aorta do not appear to diminish the risk of recurrence. A wider lateral margin and a more complete excision of the mesorectum may be beneficial, but this is yet unproven. Surgery for isolated, locally recurrent lesions should be limited to carefully selected patients and performed in tertiary centers using a team approach. Whether such radical “salvage” procedures are justifiable merits further careful evaluation.
Control of erythritol dehydrogenase in Schizophyllum commune

An NAD-dependent erythritol dehydrogenase was detected in cell-extracts of basidiospore germinants of Schizophyllum commune following culture on either meso-erythritol or glycerol as sole carbon sources. Induction of erythritol dehydrogenase was also observed in purely vegetative mycelium (str. 845 or str. 699). Erythritol dehydrogenase was not observed in ungerminated basidiospores or germinants which arose on d-glucose, d-mannitol, sorbitol, ribitol, xylitol, d-arabitol or l-arabitol. NAD-coupled polyol dehydrogenases for all the latter sugar alcohols were observed in ungerminated basidiospores, germinants, and vegetative mycelium of S. commune cultured on d-glucose. Basidiospore germination on d-glucose plus meso-erythritol led to a 90% decrease in erythritol dehydrogenase and the specific activity of ribitol dehydrogenase was directly comparable to that seen in d-glucose germinants. Storage experiments of crude extracts of meso-erythritol germinants indicated differential enzyme decay of dehydrogenases for d-mannitol, sorbitol and erythritol while the respective enzymes could be further distinguished by heat-stability as well as preferential utilization of analogues of NAD. DEAE-cellulose column chromatography led to separation of sorbitol dehydrogenase which was also active with xylitol, erythritol dehydrogenase, and mannitol dehydrogenase which was also active with d-arabitol.
The Benedicks effect: Nonlocal electron transport in metals

The Benedicks effect is the voltage difference between two points in a solid that are at the same temperature. A nonzero value may be obtained if the temperature profile between the points is asymmetric. We derive the nonlocal transport theory of a metal from the Boltzmann equation, and use the results to discuss the Benedicks effect. The nonlocal theory is needed whenever the electron mean free path has the same size as variations in the gradients of the voltage, temperature, or chemical potential.
Where is the faculty voice in recent academic decisions

Long-term traditions in academic institutions have accorded primary decision-making authority on academic matters to the professoriate. In the United States this view of the faculty role has its most explicit form in the 1966Joint Statement on Government of Colleges and Universities, I which states: 'The faculty has primary responsibility for such fundamental areas as curriculum, subject matter and methods of instruction, research, faculty status and those aspects of student life which relate to the educational process' (AAUP 1990, 123). Most govemance structures at American universities reflect this tradition (Schuster, Miller, and associates 1989). Typically, an institutionwide faculty senate exists, comprised of faculty elected by the university's schools, colleges or departments. The senate usually has standing committees, including a curriculum committee which is responsible for reviewing changes in curriculum (Gilmour i991, 29). Recently, there is concern that the centrality of the faculty role in academic decisions is threatened. As a leading researcher on governance matters has stated, '...the functional authority of the faculty's role in governance has seemed...to be under siege from all directions...' (Schuster et aL 1989, viii). Recent financial pressures have led many universities to ignore or undercut the traditional faculty role. Between 1989 and 1992, many public institutions made major decisions about academic programs in the context of a financial 'crisis'. Budgets were cut, course offerings were cancelled, and new programs were put on hold. Some faculty (primarily part-rime appointments) did not have their contracts renewed (E1-Khawas 1993). Most of these derisions were made by senior administrators, under extreme time pressures. Many of these decisions were made with little or no consultation with college faculty. Admittedly, there was an urgent need for fast decisions: for 1991-92, only half of the public universities in the United States had any increase in their operating budget, despite enrolment increases; in addition, 61 per cent had budget cuts during the Year (EI-Khawas 1992)~ The next year was almost as difficult: 6 in i0 had increases in operating budget and 4 in 10 had mid-year budget cuts (EI-Khawas 1993). 9 Still, while acknowledging the financial difficulties, it is important to consider the implications of how universities responded and what
Melatonin in the chicken brain: its origin, diurnal variation, and regional distribution.

Abstract What appears to be melatonin was demonstrated in chicken brain tissue. Brain melatonin activity was abolished by pinealectomy. There was a diurnal rhythm in brain melatonin, which, like the pineal melatonin rhythm, was high at night and low in the daytime. These findings suggest that the brain melatonin was of pineal origin. At midnight, the concentration of whole brain melatonin was five times higher than the serum melatonin level. Thus, brain tissue seems to concentrate melatonin. When analyzed by brain region, the highest level of melatonin was found in the hypothalamus, and the lowest level in the telencephalon, with the midbrain, cerebellum, and pons-medulla intermediate in concentration.
The crosslinking of actin and of tropomyosin by glutaraldehyde.

Abstract Glutaraldehyde treatment of actin results in intermolecular crosslinked oligomers for the fibrous form (F-actin) but only monomers containing intramolecular crosslinks for the globular form (G-actin). Fluorescence studies on solutions which were dialyzed to remove salt, indicated that both modified actins maintained their native structure and were stabilized against denaturation by EDTA. Glutaraldehyde crosslinks tropomyosin producing oligomers with molecular weights n × 68,000. In the presence of F-actin in 0.1M KCl, tropomyosin is crosslinked end to end giving rise to a polymer of molecular weight > 500,000, indicating the close proximity of tropomyosin molecules on the F-actin filament. Glutaraldehyde modification thus appears to be useful for the study of muscle and other protein interactions.
Datalink end-to-end system performance analysis methodology

This paper proposes a methodology developed to determine End-to-End (E-2-E) Data Link performance concentrating on the Tower and En Route domains. This methodology was developed to support the Federal Aviation Administration (FAA)'s Data Communications (Data Comm) program in allocating performance requirements. The Data Comm program is part of the FAA's NextGen initiative to implement advanced communication capabilities in the National Airspace (NAS). The methodology can be potentially applied to other Data Link systems.
Determination of atrazine and simazine in water and soil using polyclonal and monoclonal antibodies in enzyme‐linked immunosorbent assays

An enzyme‐linked immunosorbent assay (ELISA) was developed as a rapid, reproducible and cost‐effective method for routine analysis of atrazine and simazine in environmental samples. Atrazine recoveries from C18 solid phase extractions (SPE) of water spiked from 0.1 ppb to 100 ppb showed good correlations with gas chromatography (GC), [14C] atrazine radioassay and ELISA methods. The C18 cartridges demonstrated very good recovery for extracting and concentrating the herbicide by all three analytical methods. Comparison between ELISA and GC for analysis of 75 well water samples showed no false negatives and a low (5%) occurrence of false positives. Soil extracts from a controlled simazine spill were also analyzed by GC and ELISA, with excellent correlation between the two methods. Characterization of the s‐triazine assay for tolerance to organic solvents and salts demonstrated the method to be resistant to such modifiers. Additionally, comparison of two monoclonal and two polyclonal antibodies raised against...
DETECTION OF VERY SMALL NEUTRINO MASSES IN DOUBLE-BETA DECAY USING LASER TAGGING

We describe an approach to the study of neutrino masses that combines quantum optics techniques with radiation detectors to obtain unprecedented sensitivity. With our approach, the search for Majorana neutrino masses down to ~10 meV will become feasible. The experimental technique uses the detection of individual Ba+-ions in the final states of 136Xe double-beta decay via optical excitation to suppress radioactive backgrounds.
Signatures of neutral quantum Hall modes in transport through low-density constrictions

Constrictions in fractional quantum Hall (FQH) systems not only facilitate backscattering between counterpropagating edge modes, but also may have a reduced constriction filling fraction ${\ensuremath{\nu}}_{c}$ with respect to the bulk filling fraction ${\ensuremath{\nu}}_{b}$. If both ${\ensuremath{\nu}}_{b}$ and ${\ensuremath{\nu}}_{c}$ correspond to incompressible FQH states, at least part of the constriction region is surrounded by composite edges, whose low-energy dynamics is characterized by a charge mode and one or several neutral modes. In the incoherent regime, decay of neutral modes describes the equilibration of composite FQH edges, while in the limit of coherent transport, the presence of neutral modes gives rise to universal conductance fluctuations. In addition, neutral modes renormalize the strength of scattering across the constriction and thus can determine the relative strength of forward and backward scatterings.
The Rise of Man's Best Friend: The Popularity of Dogs as Companion Animals in Late Eighteenth-Century London as Reflected by the Dog Tax of 1796

ABSTRACTThe history of the relationship between humans and their companion animals is long and more than a little complex. This is in large part due to the special status of these animals. Over the years these animals have evolved socially from that of an impersonal “object” to a “subject,” i.e. a sentient being with a recognized mental and emotional life. Histories of this change in relationship are rare. This is due mainly to a lack of source material; little is available and what there is is rarely reflective of a general population. Recently, records of a 1796 English dog tax have become available and they provide a fairly complete overview of the status of the dog as a companion animal in late eighteenth-century London.The evidence indicates the dog was very popular as a companion animal in late eighteenth-century English urban society. While some of these creatures were former working-class canines others were what might be described as “professional companion animals” i.e. creatures who had no prev...
Rate of clustering in Al-Cu alloys at low temperatures

Abstract It is found that substantial resistance increases and release of energy occur in rapidly cooled Al-Cu (2 at. % Cu) alloys at temperatures at least as low as −45°C. These property changes are attributed to the formation of copper enriched clusters which are presumed to be Guinier-Preston zones or their precursors. The kinetics of this clustering in the temperature range 25°C to −45°C were investigated. It was found that the isothermal rate of clustering continuously decreases with increasing time and is greatly decreased (by factors of 10–100) by interruption of the quench from the homogenization temperature at 200°C for a few seconds. The activation energy for low temperature clustering is about 12 kcal/g atom which is near that for the annealing out of the quenched-in point defects in pure aluminum. The results are consistent with the hypothesis of Zener and Seitz that the clustering is effected by point defects retained in quenching from a high temperature. However, the dislocation glide mechanism is not yet ruled out.
Interaction of HCl with Ice: Investigation of the Predicted Trihydrate, Hexahydrate, and Monolayer Regimes

Knowledge of the interaction of hydrogen chloride (HCl) with ice is important for an understanding of heterogeneous reactions on polar stratospheric clouds. The interaction of HCl with ice as a fun...
Dirichlet L-functions and character power sums

Abstract A new representation for Dirichlet L-functions L(s, χ), valid for primitive characters χ modulo k and all complex s, is given in terms of the function F(x, s) defined for real x and R(s) > 1 by the series Σ n=1 ∞ e 2nπix n s . Evaluation of L(s, χ) for negative integer s leads to a class of identities relating mth power moments Σr=1k−1χ(r)rm with finite cotangent power sums. Special emphasis is given to the quadratic character χ(n) = ( n p ) , p an odd prime. A new proof of the functional equation for L-functions is also given.
Sex Differences: A Study of the Ear of the Beholder.

Male and female adult Ss, while performing an unrelated task, heard a single infant awakening. The infant was labeled a girl or a boy. The dependent variable was how quickly Ss responded to the crying infant. Females responded more quickly to the girl than to the boy. Males responded equally slowly to boy and girl. A questionnaire on sex differences in fragility showed that females and males tend to disagree with the proposition that girls are more fragile than boys. Thus, the females' faster response to a crying girl cannot be accounted for by a belief in sex-differential fragility. Correlations between fragility beliefs and response times to an infant indicate that sex-differential belief-behavior relationships are not the same for males and females.
Potentiation of morphine analgesia by subanesthetic doses of pentobarbital

Abstract Pentobarbital pretreatment reportedly either inhibits, enhances or has no effect on morphine analgesia. The effect of subanesthetic doses of sodium pentobarbital (8–12 mg kg −1 , SC) delivered via a delivery system on analgesia of morphine (5 mg kg −1 , SC or 1 mg kg −1 , IV) acutely administered 45 min after the sodium pentobarbital pellet implantation was assessed using the warm water (55°C)-induced tail-withdrawal reflex in male Wistar rats. Significant potentiation of morphine analgesia was observed in sodium pentobarbital as compared to the placebo-pelleted animals. Pharmacokinetic or dispositional factors were not involved in this potentiation, which was possibly due to the activation of the descending inhibitory control pathways of nociceptive spinal tail-withdrawal reflex by a combined interaction of two drugs at spinal and supraspinal sites of action, that mediate opiate antinociception.
Comparison of open versus bedside percutaneous dilatational tracheostomy in the cardiothoracic surgical patient: outcomes and financial analysis.

Background The clinical and financial outcomes of a change in practice from traditional tracheostomy (open) to bedside percutaneous dilatational tracheostomies (PDT) was evaluated in patients who underwent cardiothoracic surgery. Methods During 3 years, 86 tracheostomies were performed in more than 4,000 patients who underwent cardiac surgery, 59 open and 27 PDT. A retrospective analysis was performed comparing clinical and financial outcomes of the two groups. Results There were no significant differences in demographics, medical histories, operations, or complications between open and PDT except the open group experienced more postoperative arrhythmias (70% [41 of 59] versus 44% [12 of 27], p Conclusions There were no significant clinical differences between open and PDT in cardiac surgery patients during the 3-year study period; however, PDT offered significant cost savings.
Thermal Wake of a Single Rising Air Bubble in a Large Body of Stagnant Liquid

A computational effort was undertaken to study the thermal field behind a slowly rising solitary air bubble. Starting from rest, the bubble moves upward in water due to buoyancy force in the gravitational field and induces both internal and external motion. The bubble, being colder than the surrounding water, is heated by water. The upward motion deforms the shape of the bubble and generates a convective heat transfer process. Variation of temperature at the gas-liquid interface causes a local variation of surface tension. Although the problems of this type have been generally treated by the axisymmetric assumption, the present work employs a three-dimensional model that captures the azimuthal variation of flow parameters. High-speed photography was employed to visualize the bubble evolution from the onset until the bubble reached a certain velocity. The computations were performed using the finite-volume and Volume of Fluid (VOF) techniques. The shape and evolution of the bubble as predicted by the computations are compared with those captured on the high-speed photographs. The computations revealed details of the pressure and temperature fields inside and outside the bubble. They also indicated the thermal field in the wake region behind the bubble.© 2007 ASME
Chimeric ferritin nanocages for multiple function loading and multimodal imaging.

Nanomaterials provide large surface areas, relativeto their volumes, on which to load functions. One challenge, however, has been to achieve precise control in loading multiple functionalities. Traditional bioconjugation techniques, which randomly target the surface functional groups of nanomaterials, have been found increasingly inadequate for such control, which is a drawback that may substantially slow down or prohibit the translational efforts. In the current study, we evaluated ferritin nanocages as candidate nanoplatforms for multifunctional loading. Ferritin nanocages can be either genetically or chemically modified to impart functionalities to their surfaces, and metal cations can be encapsulated in their interiors by association with metal binding sites. Moreover, different types of ferritin nanocages can be disassembled under acidic condition and reassembled at pH of 7.4, providing a facile way to achieve function hybridization. We were able to use combinations of these unique properties to prod...
Unesco and African Historiography

Unesco's General History of Africa (henceforth GHA) is now nearing completion—seven out of the eight volumes having been published in English, at least—and the time is ripe to draw attention to its role in the historiography of African history, a role very different from that played by the Cambridge History of Africa with which it is often compared. In certain ways the Unesco project has been a unique venture, and not just in African history but, in general, because it broke with old established practice. The work was not guided by one or two editors but by a large committee. History-writing by committee seemed not only distasteful but impossible to achieve to many, both because of the practical difficulties involved and because it seemed incredible that so many editors could agree on a common text, without falling into sheer banality. Now that the volumes are out, readers can judge for themselves. Many among them actually wonder how exactly these volumes and chapters were created. Because I have been an active member of the committee since its creation in 1971 and of its bureau since 1983, I can provide a general answer to this question. But the time has also come to draw attention to the records generated by this project. Future researchers will find a huge mass of papers involving hundreds of historians of Africa that touch on practically all aspects of Africa's historiography between ca. 1965 and today.
Increased stress response and β–phenylethylamine in MAOB –deficient mice

MAOA and MAOB are key iso-enzymes that degrade biogenic and dietary amines1–5. MAOA preferentially oxidizes serotonin (5-hydroxytryptamine, or 5-HT) and nore-pinephrine (NE), whereas MAOB preferentially oxidizes β-phenylethylamine (PEA). Both forms can oxidize dopamine (DA). A mutation in MAOA results in a clinical phenotype characterized by borderline mental retardation and impaired impulse control6,7. X-chromosomal deletions which include MAOB were found in patients suffering from atypical Norrie's disease8,9, which is characterized by blindness and impaired hearing. Reduced MAOB activity has been found in type-ll alcoholism and in cigarette smokers10,11. Because most alcoholics smoke, the effects of alcohol on MAOB activity remain to be determined. Here we show that targetted inactivation of MAOB in mice increases levels of PEA but not those of 5-HT, NE and DA, demonstrating a primary role for MAOB in the metabolism of PEA. PEA has been implicated in modulating mood and affect12,13. Indeed, MAOB-deficient mice showed an increased reactivity to stress. In addition, mutant mice were resistant to the neurodegenerative effects of MPTP, a toxin that induces a condition reminiscent of Parkinson's disease.
Data traffic reduction schemes for Cholesky factorization on asynchronous multiprocessor systems

For multiprocessor systems with two level memory hierarchy; the communication requirements of parallel Cholesky factorization of dense and sparse symmetric, positive definite matrices are analyzed. The data traffic associated with computing the Chloesky factor of an nn ×n dense matrix using na processors, a ≤ 2, is shown to be O(n2+a/2), assuming that the computational load is uniformly distributed. For an nn ×n sparse matrix, representing a √n × √n regular grid graph, the corresponding data traffic is shown to be O(n1+a/2), a ≤ 1.Partitioning schemes that are variations of block assignment scheme are described. The data traffic generated by these schemes are asymptotically optimal and these schemes allow efficient use of up to O(n2) and O(n) processors in the dense and the sparse case, respectively. The block based partitioning schemes are shown to provide a better utilization of the data accessed from the shared memory and reduce the total data traffic as compared to the schemes based on the column-wise wrap around assignment.
Choosing Therapy on the Basis of Disease Classifications in Inflammatory Bowel Disease.

Crohn’s disease and ulcerative colitis (UC) are heterogeneous disorders, and as such, the response to therapy is likewise heterogeneous. Therefore, stratification of patients into distinct phenotypes and potentially genotypes will lead to more definitive answers with respect to evaluation of novel and established therapies.
Effects of miR-335-5p in modulating osteogenic differentiation by specifically downregulating Wnt antagonist DKK1

Dickkopf-related protein 1 (DKK1) is essential to maintain skeletal homeostasis as an inhibitor of Wnt signaling and osteogenic differentiation. The purpose of this study was to investigate the molecular mechanisms underlying the developmental stage-specific regulation of the DKK1 protein level. We performed a series of studies including luciferase reporter assays, micro-RNA microarray, site-specific mutations, and gain- and loss-of-function analyses. We found that the DKK1 protein level was regulated via DKK1 3' UTR by miRNA control, which was restricted to osteoblast-lineage cells. As a result of decreased DKK1 protein level by miR-335-5p, Wnt signaling was enhanced, as indicated by elevated GSK-3β phosphorylation and increased β-catenin transcriptional activity. The effects of miR-335-5p were reversed by anti-miR-335-5p treatment, which downregulated endogenous miR-335-5p. In vivo studies showed high expression levels of miR-335-5p in osteoblasts and hypertrophic chondrocytes of mouse embryos, indicating a pivotal role of miR-335-5p in regulating bone development. In conclusion, miR-335-5p activates Wnt signaling and promotes osteogenic differentiation by downregulating DKK1. This cell- and development-specific regulation is essential and mandatory for the initiation and progression of osteogenic differentiation. miR-335-5p proves to be a potential and useful targeting molecule for promoting bone formation and regeneration.
Caregiver-specific outcomes in antidementia clinical drug trials: a systematic review and meta-analysis.

OBJECTIVES: To describe the range of caregiver-specific outcomes and approaches to their study within antidementia drug trials and to quantify the effect of cholinesterase inhibitors on burden and active time use of caregivers of persons with Alzheimer’s disease (AD). DESIGN: Systematic review of English-language publications and unpublished reports of antidementia clinical drug trials that included caregiver-specific outcomes. Study characteristics and methodological quality were summarized. Random effects meta-analyses were conducted for the outcomes of caregiver burden and active time use. SETTING: Community. PARTICIPANTS: Informal caregivers of participants in clinical trials of antidementia drugs. MEASUREMENTS: Burden, time use, psychological wellbeing, healthcare costs, and ease of use of or satisfaction with intervention. RESULTS: Seventeen studies involving 4,744 subjects were identified. Four trials (n 5 1,594) met criteria for inclusion in the burden analysis, and six trials (n 5 2,286) met criteria for inclusion in the time-use analysis. Most investigations involved drugs now approved by the Food and Drug Administration for the treatment of AD; donepezil was the most frequently studied intervention in the set of studies. Methodological quality varied across trials. The weighted average effect sizes were Cohen’s d 5 0.18 (95% confidence interval (CI) 5 0.04–0.32) and d 5 0.15 (95% CI 5 0.07– 0.24) for the outcomes of caregiver burden and time use, respectively. CONCLUSION: Cholinesterase inhibitors have a small beneficial effect on burden and active time use among caregivers of persons with AD. Recommendations to enhance the quality and interpretability of AD clinical trials that involve caregiver-specific outcomes are presented. JA m Geriatr Soc 53:983–990, 2005.