cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaluation of watering to control dust in high winds.

ABSTRACT A field study was conducted to determine the effectiveness of watering in controlling PM10 emissions under high wind conditions. The focus of the study was the pickup of soil by a belly scraper at a landfill. Four low-volume PM10 samplers were positioned downwind of the storage pile (at two distances, 80 and 110 m, and two elevations, 1 and 3 m) and one was located upwind at 3 m elevation. Integrating nephelometers, which measure the particu-late light scattering coefficient, bsp, were also set up at locations 80 and 110 m downwind of the storage pile. Wind speed and direction were measured on-site. Samples were collected for two periods, one with and one without water being applied. Watering was effective at reducing PM10 emissions at wind speeds up to the maximum 18 m sec-1 observed at the landfill soil pickup operation. Measurement of bsp provided an indication of PM10 concentrations with better time resolution than samplers, but not with sufficient resolution, under the instrumental condition...
GroupTie: toward hidden collusion group discovery in app stores

The current centralized application (or app) markets provide convenient ways to distribute mobile apps. Their vendors maintain rating systems, which allow customers to leave ratings and reviews. Since positive ratings and reviews can lead to more downloads/installations and hence more monetary benefit, the rating systems have become a target of manipulation by some collusion groups hired by app developers. In this paper, we thoroughly analyze the features of hidden collusion groups and propose a novel method called \emph{GroupTie} to narrow down the suspect list of collusive reviewers for further investigation by app stores. As members of a hidden collusion group have to work together more frequently and their ratings often deviate more from apps' quality, collusive actions will enhance their relation over time. We build a relation graph named \emph{tie graph} and detect collusion groups by applying graph clustering. Simulation results show that the precision of GroupTie approaches to $99.70\%$ and the recall is about $91.50\%$. We also apply our method to detect hidden collusion groups among the reviewers of $89$ apps in Apple's China App Store. A large number of reviewers are discovered belonging to a large collusion group and several small groups.
Thrombosis in coronary drug-eluting stents: report from the meeting of the Circulatory System Medical Devices Advisory Panel of the Food and Drug Administration Center for Devices and Radiologic Health, December 7-8, 2006.

Coronary drug-eluting stents (DES) were first approved for use in the United States in 2003 (Cypher Coronary Sirolimus-Eluting Stent [SES], Cordis Corporation, Miami Lakes, Fla) and 2004 (Taxus Express Paclitaxel-Eluting Stent [PES], Boston Scientific Corporation, Natick, Mass) on the basis of randomized, blinded, controlled studies that demonstrated reduced target vessel failure (Cypher) and target vessel revascularization (TVR) (Taxus) at 9 months. Major adverse cardiac events were also significantly reduced for both DES when compared with bare metal stents (BMS). Presentations at national and international meetings in 2006 suggested that DES use may be associated with an increase in late (≥1 year after implantation) stent thrombosis (ST). Other studies suggested that there may be a significant increase in the combined end point of death and myocardial infarction (MI) compared with BMS. In response to these safety concerns, the US Food and Drug Administration (FDA) convened a meeting of the Circulatory System Medical Devices Advisory Panel. Advisory Panels make nonbinding recommendations to the FDA. Panelists recognized the need for a method to assess the true frequency of ST. However, one of the challenges in the assessment of DES ST risk is that the ST definition varies from study to study (Table 1). Differences in these on-protocol definitions of ST make it difficult to pool studies for analysis and to compare one stent to another (sirolimus-eluting versus paclitaxel-eluting). Furthermore, it is important to note that the on-protocol definition of ST for some of the clinical trials that support DES approval in the United States censored events that occurred after target lesion and/or target vessel revascularization (TLR/TVR). This means that an ST that occurs after TLR/TVR may not be counted as an ST by the on-protocol definition. Because BMS patients are more likely to experience restenosis and TLR/TVR than DES patients, more BMS patients …
Quantifying Law in Police-Citizen Encounters

The way researchers have traditionally measured police action limits their capacity to test legal theories and shed light onto the determinants of law at the initial stage of the criminal justice process. This paper describes extant police action measures and their limitations, offers a new measure that taps variation in the amount of law police officers use in encounters with citizens, presents the results of an analysis that utilizes the new measure, and discusses the implications of this new measure for legal research.
DNA sequence of a foldback transposable element in Drosophila.

The bizarre structures of the Drosophila foldback (FB) transposable elements are discussed here, and arguments favouring a transposase-mediated mobility are presented. The complete 4,089-base pair nucleotide sequence of transposable element FB4 reveals the full pattern of periodicity within the inverted repeats and the nature of the loop-inverted repeat junctions, as well as the coding potential of the loop sequence.
Fine-Needle Aspiration Cytology of Papillary Hurthle Cell Carcinoma with Lymphocytic Stroma "Warthin-Like Tumor" of the Thyroid.

Papillary Hurthle cell carcinoma with lymphocytic stroma is a recent addition to the list of variants of papillary carcinoma of the thyroid. We report the aspiration cytology and histology findings of this tumor arising in two patients. The smears were cellular, and revealed Hurthle cells arranged in three-dimensional groups, papillary fragments, and as singly dispersed cells with a prominent intimately associated inflammatory component of lymphocytes and few plasma cells. The Hurthle cells were pleomorphic and showed granular eosinophilic cytoplasm, eccentrically oriented nuclei with prominent nucleoli. Nuclear features of papillary carcinoma were present among both the cellular groups and scattered cells. The histologic examination showed a circumscribed papillary tumor comprising Hurthle cells and a brisk inflammatory component filling the stalks of papillae. These findings were consistent with a papillary Hurthle cells carcinoma with lymphocytic stroma, the so-called Warthin-like tumor of the thyroid. Hurthle cells admixed with inflammatory cells in cytology preparations can be seen in Hurthle cell nodules or neoplasms arising in a background of chronic lymphocytic thyroiditis. We suggest that a careful search for nuclear features may be helpful in diagnosing this variant of papillary carcinoma.
Therapeutic modulators of STAT signalling for human diseases

The signal transducer and activator of transcription (STAT) proteins have important roles in biological processes. The abnormal activation of STAT signalling pathways is also implicated in many human diseases, including cancer, autoimmune diseases, rheumatoid arthritis, asthma and diabetes. Over a decade has passed since the first inhibitor of a STAT protein was reported and efforts to discover modulators of STAT signalling as therapeutics continue. This Review discusses the outcomes of the ongoing drug discovery research endeavours against STAT proteins, provides perspectives on new directions for accelerating the discovery of drug candidates, and highlights the noteworthy candidate therapeutics that have progressed to clinical trials.
Opioid receptors in midbrain dopaminergic regions of the rat I. MU receptor autoradiography

Several lines of evidence indicate that an interaction exists between opioid peptides and midbrain dopaminergic neurons. The purpose of this study was to map and quantify the density of the mu opioid receptor subtype relative to the location of the dopaminergic (DA) neurons in the retrorubral field (nucleus A8), substantia nigra (nucleus A9), and ventral tegmental area and related nuclei (nucleus A10) in the rat. Sections through the rostral-caudal extent of the midbrain were stained with an antibody against tyrosine hydroxylase, as a DA cell marker, and comparable sections were processed for in vitro receptor autoradiography using the mu-selective ligand,3H-Tyr-D-Ala-N-MePhe-Gyl-ol enkephalin. In the nucleus A8 region, there were low levels of mu binding. In the rostral portion of nucleus A9, there was prominent mu binding both in the ventral pars compacta, which contains numerous DA neurons, and in regions that correspond to the location of the DA dendrites which project ventrally into the underlying substantia nigra pars reticulata. In the caudal portion of nucleus A9, mu binding was greatest in the substantia nigra pars reticulata, but also in the same region that contains DA neurons. In nucleus A10, mu receptor densities differed depending upon the nucleus A10 subdivision, and the rostral-caudal position in the nucleus. Low receptor densities were observed in rostral portions of the ventral tegmental area and interfascicular nucleus, and there was negligible binding in the parabrachial pigmented nucleus and paranigral nucleus at the level of the interpeduncular nucleus; all regions where there are high densities of DA somata. Mu binding was relatively high in the central linear nucleus, and in the dorsal and medial divisions of the medial terminal nucleus of the accessory optic system, which has been shown to contain DA dendrites. These data indicate that mu opioid receptors are located in certain regions occupied by all three midbrain DA nuclei, but in a highly heterogeneous fashion.
An Analytical Infrared Radiation Model of the Earth

The spectral distribution and total intensity of the earth’s radiation to space is of interest in the design of instrumentation systems for satellites and in the computation of radiant heat transfer to a satellite. In the absence of sufficient experimental data, an analytical model has been derived covering several types of atmospheric conditions. The necessary equations and relationships are derived, and some results (based on a 1959 ARDC model atmosphere) are presented for several different cloud conditions. An estimate of the appearance of the earth’s infrared horizon is also presented.
Plasmid distribution and analyses in Rhodopseudomonas sphaeroides

Abstract Ten strains of Rhodopseudomonas sphaeroides were analyzed by agarose gel electrophoresis for plasmid DNA content and, by filter-hybridizations, for their molecular relationships. All strains examined contained at least one plasmid. Several strains carried as many as six different plasmid species with sizes ranging from 42 to 140 kilobases (kb). Those larger than 89 kb showed extensive homology with each other; the 42-kb plasmid of R. sphaeroides strain 2.4.1. was homologous to the smaller plasmid DNA of three other strains. A partial map of the 42-kb plasmid derived from R. sphaeroides 2.4.1. was prepared by analysis of restriction endonuclease digests. Cross-hybridization among the large plasmids indicated that those present in any one strain of R. sphaeroides showed homology to one or more of the large plasmids detected in strains L and 2.4.1.
The practical inversion problem in molecular beam scattering

The present status of the inversion of molecular scattering data is reviewed with particular emphasis on the importance of the rapid quantal undulations. It is concluded that the semiclassical approximation may provide valuable guidelines for localized distortions in the phase–shift curve, but that the full quantum treatment is required for quantitative accuracy. The extension of the inversion techniques to the two–potential problem is also briefly discussed.
Mean life of the 854 keV 02+ state in 74Se and the coexistence model

Abstract The mean life of the first excited 02+ state in 74Se, only 219 keV above the first excited 2+ state at 635 keV, was measured to be 1.2±0.2 nsec, with delayed coincidence techniques. The 02+ state was populated by the decay of 74Br produced via the 60Ni(16O, pn)74Br reaction. The extracted B(E2; 02+ → 201+) value is 14±2 s.p.u. which suggests that the 02+ state is collective. Application of a coexistence model in terms of spherical and deformed shapes is discussed for 74Se.
Glenohumeral Mobility in Primates

This study refutes the traditional idea that the glenohumeral joint of hominoids is more mobile than that of other primates, a belief that forms a basis for the two prominent theories of hominoid evolution. According to the brachiation theory, many anatomical features of the hominoid shoulder (including those of the glenohumeral joint) increase shoulder mobility and are interpreted as adaptations for brachiation. The slow climbing theory explains the same set of features as adaptations for slow climbing. The slow-climbing primates should therefore also possess these features, and their glenohumeral mobility should be the same as that of hominoids and be higher than that of other primates. This study presents three-dimensional glenohumeral mobility data, measured using a single video camera method on fresh specimens. The results show that the hominoid glenohumeral joint is actually less mobile than those of non-hominoid primates, including the habitually slow-climbing lorines, but it is characterized by a smooth excursion in the scapulocranial direction.
Sweating the small stuff: microRNAs and genetic changes define pancreatic cancer.

MicroRNAs (miRNAs) are 18- to 22-nucleotide-long, single-stranded, noncoding RNAs that regulate important biological processes including differentiation, proliferation, and response to cellular stressors such as hypoxia, nutrient depletion, and traversion of the cell cycle by controlling protein expression within the cell. Many investigators have profiled cancer tissue and serum miRNAs to identify potential therapeutic targets, understand the pathways involved in tumorigenesis, and identify diagnostic tumor signatures. In the setting of pancreatic cancer, obtaining pancreatic tissue is invasive and impractical for early diagnosis. Several groups have profiled miRNAs that are present in the blood as a means to diagnose tumor progression and predict prognosis/survival or drug resistance. Several miRNA signatures found in pancreatic tissue and the peripheral blood, as well as the pathways that are associated with pancreatic cancer, are reviewed here in detail. Three miRNA biomarkers (miR-21, miR-155, and miR-200) have been repetitively identified in both pancreatic cancer tissue and patients’ blood. Those miRNAs regulate and are regulated by the central genetic and epigenetic changes observed in pancreatic cancer including p53, transforming growth factor [beta], p16INK4A, BRCA1/2, and Kras. These miRNAs are involved in DNA repair, cell cycle, and cell invasion and also play important roles in promoting metastases.
Exposure to cat allergen, maternal history of asthma, and wheezing in first 5 years of life.

Summary We looked for an association between early exposure to pets and asthma and wheezing in children whose mothers or fathers did or did not have a history of asthma. We followed up 448 children, who had at least one parent with a history of atopy, from birth to 5 years. Among children whose mothers had no history of asthma, exposure to a cat or a Fel d 1 concentration of at least 8 μg/g at the age of 2–3 months was associated with a reduced risk of wheezing between the ages of 1 and 5 years. However, among children whose mothers did have a history of asthma, such exposures were associated with an increased risk of wheezing at or after the age of 3 years. There was no association between wheezing and exposure to dog or dog allergen, and the father's allergy status had no effect on the relation between childhood wheezing and cat exposure.
Molecular Markers Useful for Detecting Resistance to Brown Stem Rot in Soybean

Brown stem rot (BSR) causes vascular and foliar damage in soybean [Glycine max (L.) Merr.]. Identification of plants resistant to BSR by inoculation with Phialophora gregata (Allington & W.W. Chamberlain) W. Gams is laborious and unreliable because of low heritability. Molecular markers linked to the resistance gene could he used to screen for resistant individuals and hasten the development of BSR resistant genotypes. The objective of this study was to develop molecular markers for efficient identification of BSR resistant plants in a breeding program. Seventeen resistant and 29 susceptible cultivars and plant introductions as well as recombinant inbred lines derived from a cross between BSR 101 and PI 437.654 were assayed by PCR-based markers derived from RFLPs K3751-1 and RGA2V-1, Satt244, or developed from bacterial artificial chromosome (BAC) sequences. The DNA markers that were developed tag the BSR locus and are informative in a diverse range of soybean germplasm. Markers detected different banding patterns between resistant and susceptible genotypes. The PCR-based markers will most likely be useful in screening for BSR resistance and allow soybean breeders to transfer rapidly resistance derived from Rbs 3 to improved cultivars or soybean lines. The markers are relatively easy-to-use, inexpensive, and highly informative. Soybean breeding efforts can now be designed to incorporate the use of marker information when parental genotypes possess contrasting banding patterns.
Tachyons and superluminal wave groups

In the approximation that every inertial observer experiences a homogeneous, uniform flow of time and sees a space that is Euclidean, the arena of physics is Minkowskian and one speed is the same in all intertial frames. If a given intertial observer finds an infinitesimal source or particle traveling faster than this fundamental speed near a given event, the source must appear in some inertial frame spread over neighboring positions at a given time as a spacelike structure. If this structure persists over a period of proper time, it can be interpreted as a wave group. If it is conserved, it can be interpreted as a line or tube of force.
Infection of cultured rat hepatoma cells by mouse mammary tumor virus

A continuous line of buffalo rat hepatoma (HTC) cells has been successfully infected with mouse mammary tumor virus (MMTV) produced by the GR mammary tumor cell line. Uniform infection required initial exposure of the HTC cells to greater than 10(5) MMTV particles per cell. The resultant chronically infected cell population was found to have stably acquired 20-30 copies of MMTV DNA. The infected cells contain viral RNA and express viral antigens; however, very few MMTV particles are released into the culture medium. In spite of the biochemical evidence for infection, we have not detected any alterations in the morphology or growth properties of the infected HTC cells. As is the case in mammary tumor cells, the intracellular concentration of viral RNA is strongly stimulated (50-150 fold) by the synthetic glucorcorticoid, dexamethasone. Thus it appears that the mechanisms by which glucorticoids regulate MMTV gene expression in mouse cells are maintained when this virus infects nonmurine cells.
Structural template formation with discovery of subclasses

A major focus of computational anatomy is to extract the most relevant information to identify and characterize anatomical variability within a group of subjects as well as between different groups. The construction of atlases is central to this effort. An atlas is a deterministic or probabilistic model with intensity variance, structural, functional or biochemical information over a population. To date most algorithms to construct atlases have been based on a single subject assuming that the population is best described by a single atlas. However, we believe that in a population with a wide range of subjects multiple atlases may be more representative since they reveal the anatomical differences and similarities within the group. In this work, we propose to use the K-means clustering algorithm to partition a set of images into several subclasses, based on a joint distance which is composed of a distance quantifying the deformation between images and a dissimilarity measured from the registration residual. During clustering, the spatial transformations are averaged rather than images to form cluster centers, to ensure a crisp reference. At the end of this algorithm, the updated centers of the k clusters are our atlases. We demonstrate this algorithm on a subset of a public available database with whole brain volumes of subjects aged 18-96 years. The atlases constructed by this method capture the significant structural differences across the group.
NVMFS: A hybrid file system for improving random write in nand-flash SSD

In this paper, we design a storage system consisting of Nonvolatile DIMMs (as NVRAM) and NAND-flash SSD. We propose a file system NVMFS to exploit the unique characteristics of these devices which simplifies and speeds up file system operations. We use the higher performance NVRAM as both a cache and permanent space for data. Hot data can be permanently stored on NVRAM without writing back to SSD, while relatively cold data can be temporarily cached by NVRAM with another copy on SSD. We also reduce the erase overhead of SSD by reorganizing writes on NVRAM before flushing to SSD. We have implemented a prototype NVMFS within a Linux Kernel and compared with several modern file systems such as ext3, btrfs and NILFS2. We also compared with another hybrid file system Conquest, which originally was designed for NVRAM and HDD. The experimental results show that NVMFS improves IO throughput by an average of 98.9% when segment cleaning is not active, while improves throughput by an average of 19.6% under high disk utilization (over 85%) compared to other file systems. We also show that our file system can reduce the erase operations and overheads at SSD.
Learning to Play the Game: Professional Development and Mentoring.

ABSTRACT During the course of a career, community college administrators are engaged in activities that are believed to enhance their skills, knowledge, and abilities. Career-related activities such as furthering one's education, participating in professional development activities, and cultivating mentoring relationships may impact the career advancement of administrators. They may also provide opportunities for administrators to grow and develop as leaders. Using social and human capital as a theoretical lens, this article provides an increased understanding of the types of formal and informal activities that senior community college administrators participate in, as well as their perceptions of whether these activities are important for career advancement and development. It also further explores the role that mentors play in the lives of administrators. Findings reveal that administrators in this study participated in a variety of professional development activities both off- and on-campus, and a majo...
Fathers and Daughters: Paternal Influence among Korean Women in Politics

Paternal influence, particularly the effect of father absence on son's development, has received considerable scholarly attention (e.g., Archer and Lloyd 1985; Benson 1968; Biller 1976, 1981; Broude 1990; Burton and Whiting 1961; Carlsmith 1964, 1973; D'Andrade 1973; Hamilton 1977; Lamb 1976, 1981; Lynn and Sawrey 1959; Parker, Smith, and Ginat 1975; Santrock 1970; Sears 1951). However, anthropological research on "the effect of the absent father on the development of a girl" has been scarce since Burton and Whiting (1961:94) raised the question for future research more than three decades ago. This study is a step toward filling the lacunae and generating hypotheses on the issue of paternal influence on daughter's development, based on my research on women in politics in South Korea. In this paper, I report and speculate on the intriguing findings regarding the contrastive patterns of father-daughter relationships (as represented by the absence of the traditionally disciplinarian father and the presence of unusually nurturant fathers, respec-
Hematoma Removal, Heme, and Heme Oxygenase Following Hemorrhagic Stroke

The hemorrhagic strokes, intracerebral (ICH) and subarachnoid hemorrhage (SAH), often have poor outcomes. Indeed, the most common hemorrhagic stroke, ICH, has the highest mortality and morbidity rates of any stroke subtype. In this report, we discuss the evidence for the staging of red blood cell removal after ICH and the significance of control of this process. The protective effects of clinically relevant metalloporphyrin heme oxygenase inhibitors in experimental models of ICH and in superficial siderosis are also discussed. We also examine literature paradoxes related to both heme and heme oxygenase in various disorders of the central nervous system. Last, new data are presented that support the concept that heme, although primarily a pro-oxidant, can also have antioxidant properties.
Protonation effects on the branching ratio in photoexcited single-walled carbon nanotube dispersions.

The ensemble PL quantum yield for raw single-walled carbon nanotubes (SWNTs) dispersed in sodium cholate (SC) is {approx}5 times greater than that for the same raw SWNTs dispersed in sodium dodecyl sulfate (SDS) and {approx} 10 times greater than the quantum yield of purified SWNTs dispersed in SC. Absorbance and Raman spectra indicate that purified SC-dispersed SWNTs and raw SDS-dispersed SWNTs are hole-doped by protonation. Experiments comparing PL emission efficiency using E{sub 2} and E{sub 1} excitation show that protonation significantly affects the E{sub 2} {yields} E{sub 1} relaxation process, which has typically been assumed to occur with unit efficiency. The E{sub 2} {yields} E{sub 1} relaxation is 5 times more efficient in producing E{sub 1} PL when SWNTs are unprotonated and protected by the SC surfactant. The results provide clear evidence that extrinsic factors, such as residual acids and the specific nature of SWNT-surfactant and SWNT-solvent interactions, can significantly affect measured SWNT luminescence quantum yields.
Quo Vadis, Poena

Objectives: To show, from a review of the history of pain management, how much progress has been made, how much is yet to be done, and what direction the future may take.Findings: Pain management has rapidly evolved during the past 40 years. It has become bifurcated into the proceduralist approach and the more conservative management approach. Unfortunately, there is a clear lack of sufficient outcome studies to identify best practices. The intrusion of managed care into pain management has compounded the problem by favoring procedures over cognitive work. For many patients, chronic pain is an existential disorder not likely to be fully ameliorated by any pill or procedure. Despite the phenomenal growth of pain science, it is acknowledged that tissue damage, pain, suffering, and disability are not tightly linked, as might be predicted by the biomedical model. The psychosocial model is similarly flawed but is supported by the contention that pain has both sensory and affective components. Chronic illness w...
Theoretical Limits on the Threshold for the Response of Long Cells to Weak Extremely Low Frequency Electric Fields Due to Ionic and Molecular Flux Rectification

Understanding exposure thresholds for the response of biological systems to extremely low frequency (ELF) electric and magnetic fields is a fundamental problem of long-standing interest. We consider a two-state model for voltage-gated channels in the membrane of an isolated elongated cell (Lcell = 1 mm; rcell = 25 micron) and use a previously described process of ionic and molecular flux rectification to set lower bounds for a threshold exposure. A key assumption is that it is the ability of weak physical fields to alter biochemistry that is limiting, not the ability of a small number of molecules to alter biological systems. Moreover, molecular shot noise, not thermal voltage noise, is the basis of threshold estimates. Models with and without stochastic resonance are used, with a long exposure time, texp = 10(4) s. We also determined the dependence of the threshold on the basal transport rate. By considering both spherical and elongated cells, we find that the lowest bound for the threshold is Emin approximately 9 x 10(-3) V m-1 (9 x 10(-5) V cm-1). Using a conservative value for the loop radius rloop = 0.3 m for induced current, the corresponding lower bound in the human body for a magnetic field exposure is Bmin approximately 6 x 10(-4) T (6 G). Unless large, organized, and electrically amplifying multicellular systems such as the ampullae of Lorenzini of elasmobranch fish are involved, these results strongly suggest that the biophysical mechanism of voltage-gated macromolecules in the membranes of cells can be ruled out as a basis of possible effects of weak ELF electric and magnetic fields in humans.
Echocardiographic assessment of cardiac disease.

The physical principles and current applications of echocardiography in assessment of heart diseases are reviewed. Technical considerations and unresolved points relative to the use of echocardiography in various disease states are stressed. The discussion covers normal mitral valve motion, mitral stenosis, aortic regurgitation, atrial masses, mitral valve prolapse, and idiopathic hypertrophic subaortic stenosis. Other topics concern tricuspic valve abnormalities, aortic valve disease, pulmonic valve, pericardial effusion, intraventricular septal motion, and left ventricular function. The application of echocardiography to congenital heart disease diagnosis is discussed along with promising ultrasonic imaging systems. The utility of echocardiography in quantitative evaluation of cardiac disease is demonstrated.
Picomole quantitation of ammonia by flow-through fluorometry

Abstract A new fiber optic fluorometer has been used to measure picomole amounts of ammonia. The method is based on the enzymatic conversion of α-ketoglutaric acid and ammonium ion to glutamate with associated oxidation of NADH. The decrease in NADH fluorescence is used to quantify sample ammonia content. The method is rapid and reproducible and is capable of resolving differences as small as 0.3 pmol between samples containing 0–7 pmol.
Hedgerows in an agri-natural landscape: Potential habitat value for native bees

Abstract Recent declines in North American honeybee populations have highlighted the importance of native bee conservation, and the need for research on the ecological requirements of native bees in farmland. In this study, we investigated the value of hedgerows as foraging habitat for native bees in mosaics of small-scale agriculture and natural vegetation in two riparian landscapes in southeast Arizona, USA. In the summers of 2002 and 2003, we surveyed bees and flowers in four habitats: hedgerows, agricultural fields, woodlots, and native woodland. We asked: (1) How do hedgerows compare to other available habitats in bee abundance and species richness? (2) How does bee species composition in hedgerows compare to species composition in agricultural fields and woodland? (3) How do flower resources in hedgerows compare to those in fields and woodland? We found that hedgerows were attractive foraging habitat for native bees, especially in early summer, when hedgerows tended to have higher species richness than other agricultural or natural habitats. Cumulative species richness was highest in agricultural fields, although cumulative species richness did not significantly differ among fields, hedgerows, and woodland. While bee faunas overlapped among habitats, bee assemblages in hedgerows were more similar to those in woodland than to those in fields. The hedgerow herbaceous flora was roughly intermediate to that of fields and woodland; hedgerows also supported high densities of woodland-characteristic shrubs. These flowering shrubs were important in attracting bees that were otherwise uncommon in the landscape, including some species that are potentially valuable pollinators of agricultural crops.
3D theory of a high-gain free-electron laser based on a transverse gradient undulator

The performance of a free-electron laser (FEL) depends significantly on the various parameters of the driving electron beam. In particular, a large energy spread in the beam results in a substantial reduction of the FEL gain, an effect which is especially relevant when one considers FELs driven by plasma accelerators or ultimate storage rings. For such cases, one possible solution is to use a transverse gradient undulator (TGU). In this concept, the energy spread problem is mitigated by properly dispersing the electron beam and introducing a linear, transverse field dependence in the undulator. This paper presents a self-consistent theoretical analysis of a TGU-based, high-gain FEL which takes into account three-dimensional (3D) effects, including beam size variations along the undulator. The results of our theory compare favorably with simulation and are used in fast optimization studies of various x-ray FEL configurations.
Advanced Computer Architecture: A Systems Design Approach

Instruction Set Design. Naming Memory Objects. Memory Allocation. Memory Organization. Single-Stream Control. Object-Oriented Processing. Static Parallelism. Message Passing. Object Sharing. Secure Computer Systems. Notation.
Ideal Binary Clutters, Connectivity, and a Conjecture of Seymour

A binary clutter is the family of odd circuits of a binary matroid, that is, the family of circuits that intersect with odd cardinality a fixed given subset of elements. Let A denote the 0,1 matrix whose rows are the characteristic vectors of the odd circuits. A binary clutter is ideal if the polyhedron $\{ x \geq {\bf 0}: \; Ax \geq {\bf 1} \}$ is integral. Examples of ideal binary clutters are st-paths, st-cuts, T-joins or T-cuts in graphs, and odd circuits in weakly bipartite graphs. In 1977, Seymour [J. Combin. Theory Ser. B, 22 (1977), pp. 289--295] conjectured that a binary clutter is ideal if and only if it does not contain ${\cal{L}}_{F_7}$, ${\cal{O}}_{K_5}$, or $b({\cal{O}}_{K_5})$ as a minor. In this paper, we show that a binary clutter is ideal if it does not contain five specified minors, namely the three above minors plus two others. This generalizes Guenin's characterization of weakly bipartite graphs [J. Combin. Theory Ser., 83 (2001), pp. 112--168], as well as the theorem of Edmonds and Johnson [ Math. Programming, 5 (1973), pp. 88--124] on T-joins and T-cuts.
Germ cell transplantation for the propagation of companion animals, non-domestic and endangered species

The transplantation of spermatogonial stem cells between males results in a recipient animal producing spermatozoa carrying a donor’s haplotype. First pioneered in rodents, this technique has now been used in several animal species. Importantly, germ cell transplantation was successful between unrelated, immuno-competent large animals, whereas efficient donor-derived spermatogenesis in rodents requires syngeneic or immuno-compromised recipients. Transplantation requires four steps: recipient preparation, donor cell isolation, transplantation and identifying donor-derived spermatozoa. There are two main applications for this technology. First, genetic manipulation of isolated germ line stem cells and subsequent transplantation will result in production of transgenic spermatozoa. Transgenesis through the male germ line has tremendous potential in species in which embryonic stem cells are not available and somatic cell nuclear transfer and reprogramming pose several problems. Second, spermatogonial stem cell transplantation within or between species offers a means of preserving the reproductive potential of genetically valuable individuals. This might have significance in the captive propagation of non-domestic animals of high conservation value. Transplantation of germ cells is a uniquely valuable approach for the study, preservation and manipulation of male fertility in mammalian species.
Pore Pressure Dissipation Behavior Surrounding Driven Piles and Cone Penetrometers

Driven piles are a common foundation used to support highway bridges. Data gathered from instrumented piles and piezocone tests in finegrained soils indicate that variable pore pressure profiles, which depend on the overconsolidation ratio of the soil, can develop during penetration. For piles driven in soft clays and silts, the pore pressure profiles developed show a monotonically decreasing response with time. However, for piles driven in heavily overconsolidated silts and clays, the pore pressure profiles show dilatory behavior, with the pore pressure behavior increasing from the initial measured value to a maximum, and then decreasing to hydrostatic values. A theoretical framework is presented that combines cavity expansion theory and critical state soil mechanics with an analytical solution to the radical consolidation equation to estimate the pore pressure response as a function of time and to evaluate the coefficient of consolidation of fine-grained soils on the basis of instrumented pile and piezo...
Institutional decay and distributional coalitions in developing countries: The argentine riddle reconsidered

This article examines the relationship between political institutions and interest group behavior within the context of developing countries, taking Argentina as an example. More specifically, it tries to explore the relationship between the decay of weak governmental institutions and the development of strong distributional coalitions following Mancur Olson's theory of interest group behavior. While integrating the findings of previous works by political scientists and economists, this article advances an explanation that links institutional weaknesses with the failure of Argentina's main distributional coalitions to develop collective action. Lastly, the study analyzes the recent economic reforms of the Menem administration and their impact on the process of democratic consolidation. Drawing upon the theoretical and empirical discussion presented, the article argues that, contrary to the opinion of many pundits, such reforms are likely to strengthen the socioeconomic power of a select number of distributional coalitions. Thus serious doubts exist about the prospects of institution-building in Argentina in the long-run.
Presidential Campaigns: 1952–1996

significant changes in party organizations and their relevance to the nomination of presi dential candidates. What this literature has so far neglected is the explicit link between nomination procedures and the possibility of maintaining democratic governance. Vari ous authors have speculated that the evolution of the presidential nominating proce dures from a party-brokered system to a candidate-centered system should have pro found implications for the way in which candidates act during the campaign and once they assume office,1 but few studies have explicitly explored the probable links between nominating procedures and governing activities.2 In this paper, we argue that as presidential campaigns have evolved from a brokered-convention system to a candidate-centered system, we should expect to see a shift in the way in which presidential candidates relate to the various elements in their nominating, electoral, and governing coalitions. We first look at the number of presiden tial issue stances taken by the candidates. We then compare these positions to the party platforms. The rate of agreement between the presidential candidates and their parties' platforms indicates the extent to which candidates take seriously the various elements of the coalitions that nominated them. Second, we categorize the types of issues that presi dential candidates address. The types of issues are relevant both to campaigns and to gov ernance. The types of issues reveal the coalitions, appeals, and strategies on which candidates will rely. If the actors in presidential campaigns have changed over time, then we should expect changes in the nature of the appeals candidates make. Finally, we com pare the stances of the candidates to positions taken by congressional leaders. If congres sional leaders have truly been excluded from the process of nominating presidential candidates, then we should expect candidates to articulate a greater number of positions that diverge from those taken by the party leaders. Congressional leaders once exercised a modicum of control over the presidential selection process. In the absence of such con trol, congressional leaders and presidential candidates are less likely to agree.
Cross-platform characterization of electron tunneling in molecular self-assembled monolayers

Electron tunneling is investigated for the alkanethiol self-assembled monolayers (SAMs) formed using three different device structures spanning from the nanometer to the micrometer scale. The measured current–voltage characteristics for the alkanethiol SAMs can be explained by the classical metal–insulator–metal tunneling model and the tunneling current exhibits overall exponential trend on the molecular length. Although different structures give consistent results (such as decay coefficient), unambiguous determination of the tunneling requires characterization of length and temperature dependencies.
Transfection of oral squamous cell carcinoma with human papillomavirus-16 induces proliferative and morphological changes in vitro

Human papillomavirus has been implicated in virtually all cervical cancers and is believed to be the primary etiological factor that transforms cervical epithelia. The presence of HPV in oral cancers suggests that HPV may play a similar role in transforming the oral epithelia. The prevalence of HPV in oral cancers is highly variable, however, presenting problematic issues regarding the etiology of oral cancers, which must be investigated more thoroughly. Past analyses of HPV in cancers of the oral cavity have largely been confined to retrospective studies of cancer patients. The purpose of this study was to examine the potential for HPV16 infection to alter the proliferative phenotype of oral squamous cell carcinoma in vitro. This study found that the oral squamous cell carcinoma cell line, CAL27, transfected with HPV16, exhibited significantly increased proliferation, compared with non-transfected CAL27. The increased proliferation was observed under low density conditions, even in the absence of serum. Moreover, these effects were specific to proliferation, adhesion, and morphology, while cell viability was not affected. This study represents one of the first investigations of the effects of HPV16 infection on the proliferation, adhesion, and morphology of an oral squamous cell carcinoma cell line in vitro. The finding that HPV16 has the ability to measurably alter adhesion and proliferative potential is significant, indicating that HPV may have multiple influences on precancerous and cancerous lesions and should be explored as a risk factor and mediator of cancer phenotypes. These measurements and observations will be of benefit to researchers interested in elucidating the mechanisms of oral cancer transformation and the factors governing carcinogenesis and progression.
Undocumented in LA: An Immigrant's Story

Undocumented in LA: An Immigrant's Story. Dianne Walta Hart. Wilmington, DE: Scholarly Resources Inc. 1997. 136 pp. (Cloth US$45, Paper US$16.95)
Topographically generated fronts, very nearshore oceanography, and the distribution of chlorophyll, detritus, and selected diatom and dinoflagellate taxa

At four sites (Sunset Bay, Miller's Cove, and Shore Acres 43° 20.13′ N; 124° 22.40′ W, Nellies Cove 42° 44.75′ N; 124° 29.75 W) along the Oregon coast, USA, relationships between fronts associated with shore-parallel foam lines and the distributions of chlorophyll, selected phytoplankters, and detritus were investigated. Sampling dates at the study sites were as follows: Sunset Bay, 1 August 1997, 25 June 1999 and 20 July 1999; Miller's Cove, 24 August 2000; Shore Acres, 19 July 1999 and 16 August 2000; Nellies Cove 17 August 2000 and 31 August 2000. Conductivity, temperature and depth data were used to describe the water masses on either side of the fronts, and vertical plankton tows with a 53-μm mesh net were used to describe the distribution of selected phytoplankters and detritus. At the cove sites during upwelling, fronts marked the presence of warm water within the bay and cooler water offshore. Chlorophyll a (Chl a) and phytoplankton concentrations were generally lower within the coves than seaward while detritus concentrations were higher. From 3 July 2000 to 15 September 2000, a period when upwelling winds from the north prevail, a time series of samples was collected at Sunset Bay. The front was only present during periods of upwelling favorable winds. During these periods there were significantly higher concentrations of Chl a, Pseudo-nitzschia spp., and Protoperidinium spp. seaward of the front than landward. During downwelling winds the front was absent and there were no significant differences in the concentrations inside and outside the mouth of the bay. At Shore Acres, an exposed, relatively straight stretch of shoreline, the shore-parallel front appears to be formed by boundary mixing. Chl a and phytoplankton from the coastal ocean spread well shoreward of the boundary-mixing front. When present, the front at the mouth of the coves and bay indicated the presence of water masses with distinct physical and biological characteristics, but not at Shore Acres. Alongshore differences in the very nearshore oceanography, by altering the availability of continental shelf phytoplankton production, may affect both the growth rates of intertidal benthic suspension feeders and community structure.
Combined carbowax-paraffin technic for microsectioning of fixed tissues.

A combined Carbowax-paraffin technic for microsectioning fixed tissues gave ribbon sections as do paraffin infiltrated and embedded tissues. Blocks of formalin or alcohol fixed tissues 2 mm. thick were infiltrated with H.E.M. (Polyethlene Glycol: Carbowax, Hartman-Leddon Co.) or with one of the following polyethylene glycol ester waxes (Glycol Products Co., Inc.) for 4 hours at (61°C.): Polyethylene Glycol 600(Di) Stearate; Carbowax 1000-(Mono) Stearate; Carbowax 4000 (Mono) Stearate; Carbowax 4000 (Mono) Laurate; Carbowax 6000 (Mono) Oleate. The Carbowax infiltrated tissues were placed for 10 minutes in xylene (61° C.), into paraffin (61° C.) for 30 minutes, then into molten paraffin contained in separate molds. (The xylene passage can be excluded for preparations which preclude its use). The blocks were hardened rapidly by submerging in ice water and were fastened to carriers as in the usual paraffin technic. Tissues were cut 6 µ thick. Segments of ribbon were spread on a water bath and mounted on slide...