cssi/SciSciGPT-SciSciNet huggingface dataset:
An optimal backtrack algorithm for tree-structured constraint satisfaction problems

Abstract This paper presents and evaluates an optimal backtrack algorithm for solving tree-structured constraint satisfaction problems—a subset of constraint satisfaction problems which can be solved in linear time. Previous algorithms which solve these problems in linear time perform expensive preprocessing steps before attempting solution. The work presented here resolves the open problem posed by Dechter (1990) on the development of an algorithm which avoids this preprocessing. We demonstrate significant improvements in average-case performance over the previous state of the art, and show the benefits provided to backtrack enhancement schemes exploiting the easiness of tree-structured problems such as the cycle-cutset method (Dechter and Pearl, 1987).
Isolated free fluid on computed tomographic scan in blunt abdominal trauma: a systematic review of incidence and management.

Background Abdominal computed tomographic (CT) scan is accepted as the primary diagnostic modality in stable patients with blunt abdominal trauma. A recent survey of 328 trauma surgeons demonstrated marked variation in the management of patients with head injuries and the finding of free intra-abdominal fluid without solid organ injury on CT scan. This study was undertaken to attempt to determine what to do when free fluid without solid organ injury is seen on abdominal CT scan in patients with blunt trauma. Methods Articles concerning the incidence and significance of free intra-abdominal fluid on CT scan of blunt trauma patients without solid organ injury were systematically reviewed. A MEDLINE search was performed using terms such as tomography-x-ray computed, wounds-nonpenetrating, small intestine/injuries, time factors, and abdominal trauma and diagnostic tests. Bibliographies of pertinent articles were reviewed. Appropriate articles were evaluated for quality and data were combined to reach a conclusion. Results Meta-analysis could not be performed because no randomized, prospective, controlled trials could be found. Forty-one articles were excluded from the analysis because they looked at only patients with known injuries to intestine, diaphragm, or pancreas and the investigation of the CT scan findings did not include negative scans. Ten articles, which described CT scan results for all patients presenting with blunt abdominal trauma for a defined period of time, formed the basis of this study. Isolated free fluid was seen in 463 (2.8%) of over 16,000 blunt trauma patients scanned. A therapeutic laparotomy was performed in only 122 (27%) of these patients. Conclusion The isolated finding of free intra-abdominal fluid on CT scan in patients with blunt trauma and no solid organ injury does not warrant laparotomy. Alert patients may be followed with physical examination. Patients with altered mental status should undergo diagnostic peritoneal lavage.
Reversal of quinone-induced chlorophyll fluorescence quenching.

Wehave used two methods to investigate the reversibility of the interaction of substituted quinones with the thylakoid membrane of plant chloroplasts. Treatment of chloroplasts with added quinones lowers the room-temperature Photosys-tem II chlorophyll fluorescence intensity by variable amounts depending on the identity and concentration of the quinone. The extent of restoration of the chlorophyll fluorescence level is used as a measure of the effectiveness of the reversal technique. One reversal method involves the addition of thiols to quinone-treated chloroplasts to alter the quinone in a chemical way via a nucleophilic 1,4-Michael addition. In general, the modified quinones exhibit a loweraffinity for the thylakoid membrane, as evidenced by an accompanying increase in chlorophyll fluorescence. The thiol concentrations necessary for quenching reversal are found to be in the order [dithiothreitol]
The effects of pre-habilitative conditioning on unloading-induced adaptations in young and aged neuromuscular systems

The capacity of pre-habilitative conditioning - exercise performed a priori - to mitigate neuromuscular maladaptations to disuse is unclear. This study evaluated pre-habilitation by examining neuromuscular junctions (NMJs) and the myofibers they innervate in young adult and aged muscles. Within each age category, 40 rats were divided into four treatment groups: 1) control, 2) hindlimb suspended (unloaded), 3) prehabilitative conditioning preceding hindlimb suspension, and 4) pre-habilitative conditioning alone. Cytofluorescent staining was used to visualize NMJs, and histochemical staining to assess myofiber profiles (size and type). Statistical analysis featured 2-way ANOVA with main effects for age and treatment, along with interaction. NMJs consistently revealed significant (P≤0.05) main effects for age, but not treatment, or interaction. Typically, aged NMJs showed elongated nerve terminal branching, and more dispersed post-synaptic clusters of ACh receptors, resulting in reduced post-synaptic area per given length of pre-synaptic branching. Analysis of myofiber profiles showed significant main effects for age, treatment, and their interaction. Aged myofibers were smaller than the young ones and a higher percentage of them were Type I. Aged fibers experienced significantly greater unloading-induced atrophy than the young ones. Pre-habilitative conditioning significantly attenuated unloading-induced atrophy among aged, but not young myofibers. It was also observed that pre-habilitative conditioning alone increased myofiber size among aged, but not young adult muscles. In summary, myofibers were more sensitive than NMJs to the treatment interventions implemented. Although more sensitive to the negative effects of muscle unloading, aged myofibers were also more responsive to the hypertrophic effects of pre-habilitative conditioning.
Overview of methods for analysing single ultrafine particles

Increasing awareness that structures and attributes on a nanometre scale within aerosol particles may play a significant role in determining their behaviour has highlighted the need for suitable single ultrafine particle analysis methods. By adopting technologies developed within complementary disciplines, together with the development of aerosol–specific methods, a basis for characterizing single sub–100 nm (ultrafine) particles and features in terms of size, morphology, topology, composition, structure and physicochemical properties is established. Size, morphology and surface properties are readily characterized in the scanning transmission electron microscope (STEM), while high–resolution transmission electron microscopy (HRTEM) allows structural information on particles and atomic clusters to sub–0.2 nm resolution. Electron energy loss spectroscopy (EELS) and X–ray emission in the STEM allow the chemical analysis of particles and particle regions down to nanometre diameters. Scanning probe microscopy offers the possibility of analysing nanometre–diameter particles under ambient conditions, thus getting away from some of the constraints imposed by electron microscopy. Imaging methods such as atomic force microscopy and near–field scanning optical microscopy (NSOM) offer novel and exciting possibilities for the characterization of specific aerosols. Developments in aerosol mass spectrometry are providing the means for chemically characterizing size–segregated ultrafine particles down to 10 nm in diameter on–line. By taking a multi–disciplinary approach, the compilation and development of complementary tools allowing both routine and in–depth analysis of individual ultrafine particles is possible.
Telling evidence: Rethinking what counts in rhetoric

Abstract After the thousands of years in which a masculine canon of rhetoric has been constructed, feminist scholars have recently worked to create a more inclusive tradition. While problems and concerns have arisen with regard to this change, my work with nineteenth‐century primary texts has convinced me that more time to explore extant texts can alleviate many of the apprehensions associated with this new research. Further time to recover, evaluate, and make meaning from additional information will allow for a more complete picture of women's rhetorical history. In addition, a greater breadth of knowledge will allow us not only to add figures to a more inclusive tradition, but to redefine what counts as evidence in evaluating rhetoric and rhetoricians. In this way we may create a more complete, honest, and interesting picture of the rhetorical tradition.
Distinct structural elements that direct solution aggregation and membrane assembly in the channel-forming peptide M2GlyR.

Restoration of chloride conductance via the introduction of an anion selective pore, formed by a channel-forming peptide, has been hypothesized as a novel treatment modality for patients with cystic fibrosis (CF). Delivery of these peptide sequences to airway cells from an aqueous environment in the absence of organic solvents is paramount. New highly soluble COOH- and NH2-terminal truncated peptides, derived from the second transmembrane segment of the glycine receptor α-subunit (M2GlyR), were generated, with decreasing numbers of amino acid residues. NH2-terminal lysyl-adducted truncated peptides with lengths of 22, 25, and 27 amino acid residues are equally able to stimulate short circuit current (ISC). Peptides with as few as 16 amino acid residues are able to stimulate ISC, although to a lesser degree. In contrast, COOH-terminal truncated peptides show greatly reduced induced ISC values for all peptides fewer than 27 residues in length and show no measurable activity for peptides fewer than 21 residu...
Drought enhances symbiotic dinitrogen fixation and competitive ability of a temperate forest tree

General circulation models project more intense and frequent droughts over the next century, but many questions remain about how terrestrial ecosystems will respond. Of particular importance, is to understand how drought will alter the species composition of regenerating temperate forests wherein symbiotic dinitrogen (N2)-fixing plants play a critical role. In experimental mesocosms we manipulated soil moisture to study the effect of drought on the physiology, growth and competitive interactions of four co-occurring North American tree species, one of which (Robinia pseudoacacia) is a symbiotic N2-fixer. We hypothesized that drought would reduce growth by decreasing stomatal conductance, hydraulic conductance and increasing the water use efficiency of species with larger diameter xylem vessel elements (Quercus rubra, R. pseudoacacia) relative to those with smaller elements (Acer rubrum and Liriodendron tulipifera). We further hypothesized that N2 fixation by R. pseudoacacia would decline with drought, reducing its competitive ability. Under drought, growth declined across all species; but, growth and physiological responses did not correspond to species' hydraulic architecture. Drought triggered an 80% increase in nodule biomass and N accrual for R. pseudoacacia, improving its growth relative to other species. These results suggest that drought intensified soil N deficiency and that R. pseudoacacia's ability to fix N2 facilitated competition with non-fixing species when both water and N were limiting. Under scenarios of moderate drought, N2 fixation may alleviate the N constraints resulting from low soil moisture and improve competitive ability of N2-fixing species, and as a result, supply more new N to the ecosystem.
A Millimeter-wave Tunable Filter Using MEMS Varactors

A mm-wave tunable 3-pole filter was developed using high-Q MEMS varactors on a quartz substrate using a coplanar-waveguide (CPW) implementation. The measured tuning range was 23.8 GHz (0 V) to 22.6 GHz (15 V) with an associated insertion loss of ?2.8 dB to ?3.8 dB, and a return loss better than ?12 dB over the entire tuning range. The measured 1-dB bandwidth was 8.4% at 23.8 GHz and 6.6% at 22.6 GHz. The extracted capacitance change in the analog MEMS varactors is 1.20. These numbers represent the best results achieved to-date for tunable filters. A larger tuning range can be obtained with the new of high-capacitance ratio varactors (2:1).
Effects of intracerebroventricular 6-hydroxydopamine on catecholaminergic fibers in the rat hypothalamus

Abstract Regeneration in the central nervous system has been claimed to be very limited and abortive, although functional regeneration of some of its pathways after destruction has been observed. The exact mechanisms by which axons regenerate fully or fail to have functional regeneration remain to be studied further. We explored whether or not there is a regional difference in regeneration of central catecholaminergic (CA) neurons in the hypothalamus of young adult rats after 6-hydroxydopamine (6-OH-DA) treatment. Four days after treatment, the numbers of CA terminals and axons were significantly reduced in the paraventricular hypothalamic nucleus, periventricular hypothalamic nucleus, supraoptic commissure (SOC), and dorsomedial hypothalamic nucleus as assessed by a morphometric quantitation on fluorescence microscopy micrographs; CA axons were gradually increased in numbers after the treatment. The number of CA varicosities in the supraoptic commissure was restored to 96% of control 180 days after the 6-OH-DA lesion, whereas the actual numbers of CA varicosities in the paraventricular, periventricular, and dorsomedial hypothalamic nuclei were attained at 79, 79, and 68% of control values, respectively. Our results indicate that CA fibers in the supraoptic commissure possess more regenerative potential than the three other hypothalamic regions studied, suggesting a regional difference in CA nerve sprouting during neuroplasticity within the hypothalamus. The favorable regeneration of CA axons in the supraoptic ommissure implies to us that some trophic features along that pathway, particularly near the third ventricle, may have been stimulated after chemical lesion using 6-OH-DA, and gradually released in the distal field of the supraoptic commissure to attract CA stumps to sprout. These factors may thus induce both regenerative sprouting and collateral sprouting resulting in vigorous regrowth of CA fibers in the supraoptic commissure.
The retrorectal space.

Ninety-nine adults with an enlarged retrorectal space on barium enema examination have been evaluated. Measurements were based on previously described methods using the lateral view of the barium filled rectum. In 38.4% of cases there was no lesion (normal variations). The rest were classified as inflammatory conditions, tumours, and miscellaneous lesions. It is concluded that an increased width of the presacral space per se does not necessarily connote a lesion. Pathological widening of the space is usually associated with changes of the contour of the rectum, abnormalities of the sacrum, or other alterations of the presacral soft tissues.
Growing Electrical Connections in Living Cells

Cellular-electrical connections have the potential to combine the specialties of the technological world with those of the living world. However, cell membranes are natural insulators, inherently creating a barrier between intracellular electrons and inorganic materials. To overcome this barrier, we have ‘grown’ electrical connections in living cells by engineering the cell to construct a well-defined electron pathway. The dissimilatory metal-reducing microbe, Shewanella oneidensis MR-1, inspired our approach: it has the unusual ability to transport electrons to extracellular minerals via a trans-membrane electron transport pathway (ETP). We seek to generalize this ability to grow electrical contacts between microbes and inorganic materials, and thus have genetically re-engineered a portion of the Shewanella ETP into Escherichia coli as a first step towards building microbial-electrical interfaces (Fig 1A). Native E. coli proteins complete the electron pathway by directly interacting with the functionally expressed Shewanella proteins. These ‘electrified’ strains exhibit ∼8x and ∼4x faster the metal reducing efficiency with soluble metals and insoluble metal oxides, respectively, than wild-type E. coli (Fig. 1B,C). These experiments provide the first steps towards engineering of hybrid living-non-living systems.View Large Image | View Hi-Res Image | Download PowerPoint Slide
Determinants of deforestation in Nepal's Central Development Region.

Abstract The process of deforestation in the Central Development Region (CDR) of Nepal is diverse in space and time, with rapid deforestation still occurring in areas outside the national parks and wildlife reserves. This paper identifies the spatial driving forces (SDFs) of deforestation in the CDR for 1975–2000 using satellite data of 1975 (MSS), 1990 (TM), and 2000 (ETM+) along with socio-demographic and socioeconomic variables. Radiometrically calibrated satellite images are individually classified into seven distinct classes and merged together to cover the entire CDR. Classification accuracies are also assessed. Areas of land use and cover within the areas of each Village Development Committee (VDC) and municipality represented by GIS polygons are calculated from the classified images by overlaying vector files of 1845 polygons representing sections of VDCs and municipalities in 30–1199 m, 1200–2399 m, 2400–4999 m and >5000 m elevation levels. These elevation levels were estimated from the DEM compiled from 24 ASTER scenes taken on different dates. Only the first three elevation levels are used in the analysis because area >5000 m is under permanent snow cover where human related forestry activities are almost negligible. A transition matrix is generated for 1975–1990 using classified images of 1975 and 1990 and then this product is used to further develop another transition matrix for 1990–2000 with the classified ETM+ 2000 images as the final stage. The GIS polygon layer is overlaid on the transition matrices to calculate deforestation areas for 1975–1990 and 1990–2000. Biophysical and socioeconomic information collected from various sources is then brought into a GIS platform for statistical analyses. Six linear regression models are estimated using SAS; in effect, two models for each elevation range representing the 1975–1990 and 1990–2000 periods of change to identify SDF influences on deforestation. These regression analyses reveal that deforestation in the CDR is related to multiple factors, such as farming population, genders of various ages, migration, elevation, road, distance from road to forest, meandering and erosion of river, and most importantly the conversion of forestland into farmland.
Considerable improvement of optical property of GaInNAs/GaAs quantum well

We have found that antimony (Sb) plays an important role for the improvement of optical properties of the GaInNAs/GaAs quantum well in the 1.3 μm region grown by metalorganic vapor-phase epitaxy. Non-annealed samples grown with pre-flow of trimethylantimony (TMSb) showed good optical properties equivalent to that of annealed samples grown without TMSb. These samples showed higher tolerance to thermal annealing and maintained good photoluminescence (PL) intensity up to 720 °C. The atomic force microscope image showed the improvement of surface smoothness. These results suggest supplying TMSb only before the growth of the quantum well is effective for the improvement of interface between GaInNAs and GaAs.
Binary metal alloy clusters

Binary alloy clusters A n B m (A, B: Bi, Sb, Pb, Ag, in different compositions) have been generated by simultaneous inert gas condensation of the two vapours. Under suitable condensation conditions the adsorption of single atoms A to clusters B m can be studied. The adsorption probabilities are found to vary with cluster size. The cluster reactivities depend on the number of absorbed foreign atoms. Lead and bismuth clusters are found to be highly reactive in cracking the strongly bound Sb4-tetrahedron. One single interaction channel is found for Pb n /Sb4 (symmetrical dissociation) and three interaction channels are found for Bi n /Sb4 (symmetrical and nonsymmetrical dissociation). Pb- and Bi- clusters have different onset thresholds for dissociative reactivity.
Isolation and preparation of colonies grown on soft agar for ultrastructural investigation.

SUMMARY Preparation of cell colonies grown on soft agar for electron microscopic examination is tedious. Mechanical damage to cells can occur during the process of colony removal. A procedure which permits rapid colony removal and preserves the integrity of the individual colony for ultrastructural examinations is described in this paper.
Causal Mechanism-based Model Constructions

We propose a framework for building graphical causal model that is based on the concept of causal mechanisms. Causal models are intuitive for human users and, more importantly, support the prediction of the effect of manipulation. We describe an implementation of the proposed framework as an interactive model construction module, Ima-GeNIe, in SMILE (Structural Modeling, Inference, and Learning Engine) and in GeNIe (SMILE'S Windows user interface).
IMMUNOCHEMICAL STUDIES ON BLOOD GROUPS : IV. PREPARATION OF BLOOD GROUP A SUBSTANCES FROM HUMAN SOURCES AND A COMPARISON OF THEIR CHEMICAL AND IMMUNOCHEMICAL PROPERTIES WITH THOSE OF THE BLOOD GROUP A SUBSTANCE FROM HOG STOMACH.

1. Blood group substances have been prepared from human saliva, stomach, and amniotic fluid from individuals of blood group A1 and A2. Several of the saliva samples were obtained from individuals shown to be heterozygous, A1O. 2. The purified blood group A substances from human sources were similar in nitrogen, glucosamine, reducing sugar, and acetyl content. The A1 and A2 substances differed in optical rotation. All of the human A samples were levorotatory while those from hog stomach were dextrorotatory. 3. By two immunochemical criteria the various human preparations could be shown to fall into distinct groups, with respect to purity. The best products showed maximal activity and almost all of their glucosamine was specifically precipitable by anti-A. These samples of human A substance were only about one-half as effective in precipitating antibody to hog A substance formed in man as was homologous hog A substance although the same total amount of antibody was precipitable by excess of either antigen. 4. Human blood group A1 substance was found to be antigenic in individuals of blood groups B and O but was not as good an antigen as hog A substance.
F-actin cleavage in apoptotic outer hair cells in chinchilla cochleas exposed to intense noise

Apoptosis is an active cell death pathway involved in a variety of pathological conditions, including noise-induced outer hair cell (OHC) death. During this process, the cytoskeletal proteins have been found to be either damaged and/or enzymatically disassembled in several cell types, leading to formation of apoptotic manifestations. This study was designed to examine the cleavage of filamentous actin (F-actin), an important cytoskeletal protein, in the cochlear OHCs after noise exposure. Chinchillas were exposed to a 4 kHz narrow band noise at 106 dB SPL for 1 h and cochleas were either collected immediately or 3 h after the noise exposure. The organs of Corti were double-stained using FITC-labeled phalloidin for F-actin and propidium iodide for OHC nuclei. The effect of noise on F-actin and nuclei was examined by confocal microscopy. The result showed that the fluorescence associated with F-actin was decreased in the OHCs possessing condensed nuclei, but remained unchanged in the OHCs with swollen nuclei. The change in F-actin labeling occurred coordinately with the changes in nuclear morphology of apoptotic cells and was prevented by administration of caspase-3 inhibitor (Z-DEVD-FMK). The results of this study indicate that F-actin cleavage is an important early cellular event in apoptotic development in OHCs following exposure to traumatic noise.
Atmospheric pathways of the phosphorus cycle

Abstract Extensive measurements have been made of atmospheric P concentrations and deposition rates in marine and remote continental areas. These data, when combined with other published data on P deposition rates over the continents, have enabled the estimation of the atmospheric burden the sources, the sinks, and the transfer rates of P through the atmosphere. We estimate that the total atmospheric burden of P is ~ 2.8 ×1010g 90% of which is over the continents. Deposition rates are calculated to be ~320 ×1010g yr−1 of P onto the continents and ~140 ×1010g yr−1 onto the surface of the ocean. Major sources of particulate P in the atmosphere are estimated to be: 1. (1) soil particles containing both naturally occurring and fertilizer derived P, ~400 ×1010g yr−1; 2. (2) P on sea-salt particles, ~ 33 ×1010g yr−1 3. (3) P from industrial sources. ~26 ×1010g yr−1. The major sources of industrial P emissions are the phosphate industry, ~16 ×1010 g yr−1 and stationary combustion sources, ~ 5.7 ×1010g yr−1. A net flux of ~100 ×1010g yr−1 of P is transported from the continents to the oceans through the atmosphere. Almost 50% of this transport is due to the flux of dust from the Sahara desert to the North Atlantic between 15° and 25°N. The input of P which is easily soluble in sea-water is estimated to be 22 ×1010g yr−1. This value is about 10% of the input of dissolved P to the oceans by rivers.
Split Roles in Performance Evaluation—A Field Study Involving New Teachers

Prescriptive writings on performance evaluation have argued that splitting the administrative (summative) and developmental (formative) roles will lead to evaluatees being less defensive and more open to discussing performance problems and taking suggestions, and that without the responsibility for making an administrative evaluation, evaluators will be able to provide more assistance toward improving performance. These results of splitting the roles should lead to greater improvement in the performance of evaluatees. This article describes the results of a study of splitting the roles between two people. Newly hired teachers in a Midwestern school district were assigned to either a split role group, in which developmental evaluation and feedback were provided by a peer mentor, and administrative evaluation by managers and peer evaluators, or a combined role group, in which developmental evaluation, feedback, and administrative evaluation were provided by a peer. Reactions of evaluatees were assessed using interviews and a survey, and performance ratings and turnover were analyzed. There were no major differences between the groups in terms of openness to discussion of difficulties, reception and acceptance of performance feedback, stress, turnover intentions, actual turnover, or performance improvement. These results suggest that it may be more important to ensure that developmental assistance is provided to evaluatees than to split the evaluation roles.
Special Issue on Microfracture

Articular cartilage injuries are common and have been found in approximately 60% of knees1,2 and 5% of shoulders3 undergoing arthroscopy. While many of these are incidental findings, the remainder are often symptomatic and debilitating and present a unique challenge secondary to the poor regenerative capacity of the native tissue. Cartilage repair procedures play an integral role in the treatment of these injuries and serve as a therapeutic bridge between debridement and arthroplasty. Technology is rapidly advancing, and emerging treatments have evolved to include minced autologous cartilage, minced juvenile allograft cartilage, scaffolds, and cell-infused matrices; however, tissue durability and outcomes of these procedures have yet to be defined. Despite the developments, the most tried and true treatment for cartilage injury is microfracture. This technique, which was developed and first described by Steadman in 1999,4 is the most common reparative procedure performed in the United States with over 25,000 cases annually.5 By some estimates, more than 100,000 microfracture procedures are performed annually. Appropriately, this issue is dedicated to this procedure. Microfracture is a time-tested technique that has consistently demonstrated improved outcomes in the treatment of symptomatic cartilage defects in the knee6 and is now showing promise in the shoulder7 and hip8 as well. Dr. Richard Steadman is credited for his visionary thinking and deserves credit for this foresight. His commitment to clinical follow-up, the basic science that has furthered our surgical techniques, and the commitment of others who are now reporting their outcomes have led microfracture to become the comparator to emerging technologies. Those of us who treat these patients are indebted for his contribution.
Flagellar elongation: An example of controlled growth

Flagella grow by the addition of precursor molecules to the distal end of the flagellar fibers. Two models for flagellar growth are set up assuming that growth is controlled by the concentration of one of the polymerization participants at the reaction site. This is an example of a way in which a cell could measure distance. The first model is stochastic in nature. It yields a distribution for flagellar fiber lengths which is in keeping with reported results. It also accounts for the observed dependence of growth rate on initial length in regenerating flagella. The second model is based on a pair of linear differential equations, and is an outgrowth of the stochastic model. Interphase growth, long-zero behavior in Chlamydomonas , and flagellar response to treatments with colchicine and cycloheximide are discussed in relation to the second model. It is proposed that changes in the physical parameters of the flagellar system are required before flagellar regression can occur.
Characterization and transmission of an agent producing a neurological disease in infant mice (IMNV).

A neurological disease appeared in infant NCS mice during the course of experiments on stunted growth. Signs of uncoordination appeared 5 to 17 days (usually 5 to 7) following oral or parenteral inoculations of infant mice with intestinal or other organ homogenates or filtrates. Death occurred a few hours after the onset of illness. The disease was readily transmitted by oral infection (serial passages) but was not communicable through contact. Weaned mice were not susceptible. Organ homogenates retained activity on filtration through Millipore discs of 0.22 μ but not 0.10 μ. The agent was ether resistant but heat sensitive. The characteristics of the disease are sufficiently different from those produced by the known neurotropic murine viruses to warrant regarding it as a new murine syndrome.
Teaching the Finite Element Method: A Sophisticated Approach [Book review]

Here, Prodyot K. Basu reviews the book The Finite Element Method by Mats G. Larson and Fredrik Bengzon, assessing its contents, organization, and the audience for which it's suitable.
Cytokine levels during symptomatic viral upper respiratory tract infection.

Background Previous studies suggest a role for locally produced proinflammatory cytokines in the development and expression of illness during experimental infection with a variety of respiratory viruses. However, most of these studies fail to make comparisons between symptomatic and asymptomatic infected subjects. Objective To compare the pattern of nasal cytokine elaboration in asymptomatic and symptomatic subjects experimentally infected with rhinovirus-39 (RV-39). Methods Healthy adults underwent experimental intranasal inoculation with a safety-tested clinical isolate of RV-39. Nasal lavages were collected, nasal symptoms were recorded, and expelled nasal secretions were weighed before and then daily for 6 days after challenge. Nasal lavages were submitted for viral culture and assayed for cytokine protein levels by enzyme-linked immunosorbent assay. Results Twenty-nine subjects were enrolled in the study. All subjects were infected as evidenced by viral shedding and/or seroconversion. Sixteen subjects were symptomatic and 13 were asymptomatic as evaluated by subject self-report. During infection, significant increases in mean levels of nasal interleukin 6 (IL-6) ( P = .01) and IL-1 ( P = .02) were observed in symptomatic but not asymptomatic subjects. In symptomatic subjects, these increases were temporally related to the development of nasal symptoms and production of secretions. Mean levels of IL-8, IL-10, and tumor necrosis factor α were not increased in either group during infection. Conclusions The results of this study demonstrate elevations in certain locally produced cytokines during symptomatic but not asymptomatic respiratory infection with RV-39. Future studies using selected anticytokine therapies may help elucidate the precise role of cytokines in mediating disease expression.
Antimicrobial reactive oxygen and nitrogen species: concepts and controversies

Phagocyte-derived reactive oxygen and nitrogen species are of crucial importance for host resistance to microbial pathogens. Decades of research have provided a detailed understanding of the regulation, generation and actions of these molecular mediators, as well as their roles in resisting infection. However, differences of opinion remain with regard to their host specificity, cell biology, sources and interactions with one another or with myeloperoxidase and granule proteases. More than a century after Metchnikoff first described phagocytosis, and more than four decades after the discovery of the burst of oxygen consumption that is associated with microbial killing, the seemingly elementary question of how phagocytes inhibit, kill and degrade microorganisms remains controversial. This review updates the reader on these concepts and the topical questions in the field.
Forecasting Warm-Season Burnoff of Low Clouds at the San Francisco International Airport Using Linear Regression and a Neural Network

Abstract In this study, both linear regression and a nonlinear neural network are used to forecast burnoff of low clouds in the warm season at San Francisco International Airport (SFO). Both forecast systems show skill scores between 0.2 and 0.25 in comparison with use of climatological values. The neural network is slightly more skillful. The forecast systems are derived from 45 yr of NCEP–NCAR reanalysis data and SFO surface observations. A forecast is attempted for both the time of burnoff and the probability of being burned off by 1000 Pacific standard time. The lack of significant superiority of the neural network over linear regression is not due to a failing of the neural network as a method. When both methods are applied to a statistical prediction of the afternoon temperature at SFO, based on early morning conditions, the neural network has a skill score of 0.446 and the linear regression has a skill score of 0.290.
Targeting the ultrastructural origins of field carcinogenesis using low coherence enhanced backscattering

Ultrastructural alterations in precancerous tissue create an environment which is conducive to cancer development. While these changes are not visible using conventional microscopy, they can be targeted using low coherence enhanced backscattering.
Gene Differences between Caucasian, Negro, and Japanese Populations

The numbers of gene (codon) differences per locus between two randomly chosen genomes within and between Caucasian, Negro, and Japanese populations have been estimated from gene frequency data for protein loci. The estimated number of gene differences between individuals from different populations is only slightly greater than the number between individuals from the same population.
In Vivo Evolution of a Catalytic RNA Couples Trans-Splicing to Translation

How does a non-coding RNA evolve in cells? To address this question experimentally we evolved a trans-splicing variant of the group I intron ribozyme from Tetrahymena over 21 cycles of evolution in E.coli cells. Sequence variation was introduced during the evolution by mutagenic and recombinative PCR, and increasingly active ribozymes were selected by their repair of an mRNA mediating antibiotic resistance. The most efficient ribozyme contained four clustered mutations that were necessary and sufficient for maximum activity in cells. Surprisingly, these mutations did not increase the trans-splicing activity of the ribozyme. Instead, they appear to have recruited a cellular protein, the transcription termination factor Rho, and facilitated more efficient translation of the ribozyme's trans-splicing product. In addition, these mutations affected the expression of several other, unrelated genes. These results suggest that during RNA evolution in cells, four mutations can be sufficient to evolve new protein interactions, and four mutations in an RNA molecule can generate a large effect on gene regulation in the cell.
The (3He, tf) as a surrogate reaction to determine (n, f) cross sections in the 10–20 MeV energy range

Abstract The surrogate reaction 238 U( 3 He, tf ) is used to determine the 237 Np( n , f ) cross section indirectly over an equivalent neutron energy range from 10 to 20 MeV. A self-supporting ∼761 μg/cm 2 metallic 238 U foil was bombarded with a 42 MeV 3 He 2+ beam from the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory (LBNL). Outgoing charged particles and fission fragments were identified using the Silicon Telescope Array for Reaction Studies (STARS) consisted of two 140 μm and one 1000 μm Micron S2 type silicon detectors. The 237 Np( n , f ) cross sections, determined indirectly, were compared with the 237 Np( n , f ) cross section data from direct measurements, the Evaluated Nuclear Data File (ENDF/B-VII.0), and the Japanese Evaluated Nuclear Data Library (JENDL 3.3) and found to closely follow those datasets. Use of the ( 3 He, tf ) reaction as a surrogate to extract ( n , f ) cross sections in the 10–20 MeV equivalent neutron energy range is found to be suitable.
Thalidomide: The Past, Present, and Future

Treatment Review is intended to inform and update nurses about treatments relevant to HIV/AIDS. Product information presented in this column does not imply endorsement by the Association of Nurses in AIDS Care.
Increased intravenous drug self-administration during deprivation of other reinforcers

Abstract Previous research has shown that food deprivation markedly increased self-adminstration of a variety of drugs. The present study concerns an extension of the food deprivation effect to a range of doses and other forms of deprivation. In each experiment, etonitazene infusions were continously available to rats under the following sequence of satiation (S) or deprivation (D) sessions: S, S, D, S, S, D, S, S, D, S, S, S. Each infusion contingent upon a lever-press response, and session lenght was 4 hr. In the first experiment, five groups of rats, each receiving a different etonitaze dose: 0 (saline), 5, 10, 20 or 40 μg/kg, were tested under conditions of food satiation (free access) and deprivation (8 g food, sessions). Food deprivation produced no increases in responding maintained by saline, but it produced nearly parallel increases in respon3ing across all drug doses. In the second experiment, effects of water satiation (free access) and deprivation (no water) were tested at the 10 μg/kg etonitaze unit dose. Etonitazene-maintained responding was more than twice as high during water deprivation sessions as during satiation sessions. In the third experiment, rats receiving saline infusion (after brief exposure to 10 μg/kg etonitazene infusions to elevate response rates) did not show any systematic changes in saline-maintained behavior as a result of water deprivation or satiation. In the fourth experiment, rats were allowed continous access to food, water and etonitazene infusions (10 μg/kg). In addition, they were given a drinking solution containing 3% glucose and 0.125% saccharin (G + S). When the rats were deprived of the G + S solution, they showed small but reliable increases in etonitazene self-administration. The present results extend previous findings with food deprivation to a range of doses and other deprivation conditions, suggesting that drug-maintained behavior can be controlled by alterations in a variety of other reinforcing events in the environment.
Serum-associated inhibition of leukotaxis in humans with cancer.

Abstract Human patients with a variety of malignant tumors have been studied to characterize the reported abnormality of leukotactic function. A majority of patients show a leukotactic defect that is serum associated and due to the presence of an inhibitor. This inhibitor impairs both neutrophil and monocyte reactivity to a variety of leukotactic factors. Phagocytic ability of leukocytes is also impaired by cancer serum and by the fractions of serum rich in the leukotactic inhibitor. The leukotactic inhibitor is cell directed in its function, is heat-stable and can be precipitated from serums with ammonium sulfate. Its sedimentation coefficient is biphasic, with values of approximately 7S and 10S. A similar or identical inhibitor is present in much lower concentration or activity in normal human serum. The presence in cancer serum of this leukotactic inhibitor may account for the well-known defects in the ability of cancer patients to express cellular inflammatory reactions.
Neurocognitive outcomes and recovery after pediatric TBI: Meta-analytic review of the literature

Traumatic Brain Injury (TBI) continues to be one of the leading causes of death and disability in the pediatric population. Although the literature on neurocognitive outcomes is relatively rich, studies vary significantly in the methods used to group subjects on several moderating variables, including age at injury, injury severity, and time since injury, making it difficult to combine and summarize the data for comparison. Further complicating this effort is the wide range of measures used to document functional outcomes in key neurocognitive domains. In this meta-analytic review, 28 publications (1988 to 2007) that met inclusion criteria were summarized based on three distinct injury severity and time post injury groups for 14 key neurocognitive domains. Effect sizes were calculated to reflect the extent to which the above groups differed in case-control and case-case studies, as well as address recovery based on longitudinal studies. To the best of our knowledge, this is the first published quantitative summary of the literature on neurocognitive outcomes after pediatric TBI. Limitations of the current state of the literature as well as recommendations for future studies are discussed.
Severity of diabetic foot infection and rate of limb salvage.

Background:Foot infections are limb-threatening complications in patients with diabetes mellitus (DM), and proper classification of the severity of diabetic foot infection (DFI) is important in det...
Optimizing instruction cache performance for operating system intensive workloads

High instruction cache hit rates are key to high performance. One known technique to improve the hit rate of caches is to use an optimizing compiler to minimize cache interference via an improved layout of the code. This technique, however, has been applied to application code only, even though there is evidence that the operating system often uses the cache heavily and with less uniform patterns than applications. Therefore, it is unknown how well existing optimizations perform for systems code and whether better optimizations can be found. We address this problem in this paper. This paper characterizes in detail the locality patterns of the operating system code and shows that there is substantial locality. Unfortunately, caches are not able to extract much of it: rarely-executed special-case code disrupts spatial locality, loops with few iterations that call routines make loop locality hard to exploit, and plenty of loop-less code hampers temporal locality. As a result, interference within popular execution paths dominates instruction cache misses. Based on our observations, we propose an algorithm to expose these localities and reduce interference. For a range of cache sizes, associativities, lines sizes, and other organizations we show that we reduce total instruction miss rates by 31-86% (up to 2.9 absolute points). Using a simple model this corresponds to execution time reductions in the order of 12-26%. In addition, our optimized operating system combines well with optimized or unoptimized applications. >
DIAMOND-CERAMIC COMPOSITE TOOL COATINGS

We have developed multilayer composite diamond coatings with improved adhesion and wear resistance on WC(Co) tool substrates. The coatings consist of a first layer of discontinuous diamond crystallites that are anchored to the WC(Co) substrate by an interposing layer of ceramic films. These films consist of TiC, TiN, SiC, Si3N4 or WC deposited to provide a conformal coverage on the first layer of diamond. A second or final layer of continuous diamond film is deposited to provide the cutting edge of the tool. The diamond film in the composite layers is deposited by hot filament chemical vapor deposition (HFCVD) and the interposing layer is deposited by laser physical vapor deposition (LPVD). The different parameters associated with the deposition of diamond and interposing layers are optimized to improve the adhesion and wear resistance. We have studied the adhesion characteristics by indentation tests in which the critical load for peeling of the diamond films is determined. Adhesion and wear resistance of the films are also tested using an overlap polishing on diamond paste with 5–6 μm particle size. The diamond and interposing layers in the composite are characterized by scanning electron microscopy and Raman spectroscopy. Results of improvement in adhesion and wear resistance are correlated with the quality of the diamond film and the interposing layer. Better accommodation of thermal stresses and strains in the composite layers has been shown to be responsible for improvement in the adhesion and wear resistance of the composite diamond films.
Dietary self-monitoring and its impact on weight loss in overweight children.

Objective. To examine whether dietary self-monitoring is related to weight loss in overweight children and whether perceived social support or dietary self-efficacy affects this relation. Design. L...
Gonadectomy and Hormone Replacement Affects In Vivo Basal Extracellular Dopamine Levels in the Prefrontal Cortex but Not Motor Cortex of Adult Male Rats

Gonadectomy in adult male rats is known to impair performance on dopamine (DA)-dependent prefrontal cortical tasks and selectively dysregulate end points in the mesoprefrontal DA system including axon density. In this study, in vivo microdialysis and high-pressure liquid chromatography were used to determine whether short (4 day)- and/or long-term (28 day) gonadectomy and hormone replacement might also influence the more functionally relevant metric of basal extracellular DA level/tone. Assessments in medial prefrontal cortex revealed that DA levels were significantly lower than control in 4-day gonadectomized rats and similar to control in 4-day gonadectomized animals supplemented with both testosterone and estradiol. Among the long-term treatment groups, DA levels were significantly higher than control in gonadectomized rats and gonadectomized rats given estradiol but were similar to control in rats given testosterone. In contrast, extracellular DA levels measured in motor cortex were unaffected by long- or short-term gonadectomy. The effects of gonadectomy and hormone replacement on prefrontal cortical DA levels observed here parallel previously identified effects on prefrontal DA axon density and could represent hormone actions relevant to the modulation of DA-dependent prefrontal cortical function and perhaps its dysfunction in disorders such as schizophrenia, attention deficit hyperactivity disorder, and autism where males are disproportionately affected relative to females.