cssi/SciSciGPT-SciSciNet huggingface dataset:
A new approach to dislocation creep

Abstract A new approach to dislocation creep is proposed based on a reappraisal of diffusion controlled glide as outlined by Hirth and Lothe. It is argued that creep may be viewed as a process of thermally activated release of dislocations from pinning centers and the latter could be dislocation related features such as nodes, kinks and jogs or nanoscale particles with incoherent interfaces. It is shown that the proposed approach is able to explain the creep behavior of materials that represent both these classes. It is shown that, contrary to extant theories, superalloys and pure metals fall within the first class while ferritic steels represent the second class of materials. A simple equation relating creep rate to stress is derived to describe the creep behavior as per the above philosophy and is shown to represent the creep data of a vast range of materials. The proposed equation obviates the need for the traditional power law approaches to creep with arbitrary exponents of stress. The applicability of the basic constitutive equation developed here to modeling of the creep strain vs. time behavior is demonstrated by combining it with equations from the damage mechanics philosophy. It is shown that the creep data of GTD111, a typical γ′ strengthened Ni-base superalloy, are predicted well by this equation set.
Using effective teaching practices in the special education classroom

Abstract Research on effective schooling has led to conclusions regarding classroom practices. This research has implications for special educators, who need to become familiar with it. The implications which are discussed in this article are related to the need for planning, high expectations of student performance, monitoring student progress and providing feedback, establishing classrom routines, grouping, academic learning time, personal relationships and the use of incentives and rewards. These conclusions regarding effective teaching can be used diagnostically by teachers to evaluate and improve their own performance in the classroom. In this article some conclusions based on a review of effective teaching research will be outlined and implications for the special education classroom will be discussed.
Cholinergic agonists inhibit HMGB1 release and improve survival in experimental sepsis.

Physiological anti-inflammatory mechanisms can potentially be exploited for the treatment of inflammatory disorders. Here we report that the neurotransmitter acetylcholine inhibits HMGB1 release from human macrophages by signaling through a nicotinic acetylcholine receptor. Nicotine, a selective cholinergic agonist, is more efficient than acetylcholine and inhibits HMGB1 release induced by either endotoxin or tumor necrosis factor-alpha (TNF-α). Nicotinic stimulation prevents activation of the NF-κB pathway and inhibits HMGB1 secretion through a specific 'nicotinic anti-inflammatory pathway' that requires the α7 nicotinic acetylcholine receptor (α7nAChR). In vivo, treatment with nicotine attenuates serum HMGB1 levels and improves survival in experimental models of sepsis, even when treatment is started after the onset of the disease. These results reveal acetylcholine as the first known physiological inhibitor of HMGB1 release from human macrophages and suggest that selective nicotinic agonists for the α7nAChR might have therapeutic potential for the treatment of sepsis.
Surface plasmon polariton enhanced upconversion in rare earth doped nano crystals on plasmonic substrates

Plasmonic enhancement of near infra-red to visible upconversion could potentially yield high-efficiency spectral converters for solar cells. We use spectroscopic imaging to investigate the intensity enhancement and modification of radiative rates of infra-red to visible upconversion from rare-earth doped nanoparticles (NaYF 4 :Yb:Er[Tm]) supported on substrates designed to support a surface plasmon polariton at frequencies which are near-resonant with the rare-earth sensitizer (Yb3+) absorption. Using spatially-resolved spectroscopic imaging, we directly observe a systematic enhancement in the efficiency of upconversion associated with the interaction of the co-doped nano-particles with the plasmonic substrates. Spectrally resolved reflectivity and time-resolved luminescence decay measurements support our interpretation.
The use of time and trajectory forms as visual information about spatial scale in events

Spatial metrics are lost but temporal metrics are preserved in the mapping from events to optic flow. In inanimate events governed by gravity, temporal scale is linked to spatial scale in ways specific to particular events. We tested whether time can be used as information about spatial scale in visually recognizable events. On average, observers were able to judge object size in event displays that eliminated information other than time and trajectory forms. However, judgment variability was substantial. After feedback on one event, observers judging distance performed better and generalized training to other events. Observers are sensitive to the general form of the scaling relation, but they require feedback to attune event-specific constants.
Photoionization of acceptors in uniaxially stressed germanium

Abstract The impurity photoconductivity of Al and B-doped germanium has been measured at temperatures of 2.0 and 7.5 K with uniaxial stress along the [100] and [111] axes. The results obtained at 2 K show that the ionization energy of acceptors decreases with stress. The biggest decrease was observed for stress along the [100] direction. Deformation potential parameters b = - 1.9±0.3 eV and d = - 7±1.7 eV were obtained by comparing the results with Price's theory. These values depend slightly on the type of impurity. Lines due to bound excited states are observed at 7.5 K. In high stress ( > 3 x 109 dyn/cm2) the influence of stress on the ground state is greater than on the excited states.
Rapid Development of Drug-Resistant Mutants of Poliovirus

Guanidine hydrochloride is a potent inhibitor of poliovirus synthesis in cell culture. However, the viral progeny which do grow in the presence of guani-dine may become approximately 10,000 times more resistant to the drug. The phenomenon of drug resistance poses yet another problem in the search for a satisfactory viral chemotherapeutic agent.
Texture development and superconducting properties of YBa2Cu3Ox thin films prepared by a solution process in low oxygen partial pressure

YBa2Cu3Ox (YBCO) thin films on single crystal LaAlO3 substrates were prepared from a trifluoroacetate (TFA) precursor heat treated in a low oxygen partial pressure argon atmosphere. The purpose of the study was to explore the possibility of forming high-purity, epitaxial YBCO films at heat treatment temperatures and oxygen partial pressures low enough to allow the TFA process to be adapted to metallic substrates. The formation of a superconducting YBCO phase was confirmed by measuring the critical temperature (Tc) inductively. In-plane texture and c-axis alignment of the films were determined from x-ray phi scans and omega scans, respectively. Raman microspectroscopy was used to interrogate grain connectivity, oxygen stoichiometry, c-axis verticality with respect to the substrate, and second phase formation. The optimum heat treatment temperature was found to be near 750 °C in an argon atmosphere, the equivalent oxygen partial pressure, which was about 10-5 atm. The full-width half-maxima (FWHMs) of the YBCO (113) phi and (005) omega scans for a sample prepared at 750 °C were about 0.6 and 0.5°, respectively, which indicates that the film was epitaxial. This film showed a sharp superconducting transition at 91 K and an inductive critical current density of 1.3 MA cm-2 at 77 K. The ability to form high-quality YBCO films under the conditions used is consistent with the thermodynamic predictions that the optimal heat treatment temperature decreases as oxygen partial pressure decreases. The results of this study define YBCO formation conditions for TFA-based precursors that may be suitable for application on metallic substrates.
Management of common bile duct stones

Choledocholithiasis remains a complicated and challenging disease process for today’s clinicians. Transabdominal ultrasound and ERC are the most common preoperative imaging modalities with endoscopic ultrasound, MRCP, and HCT emerging as potentially more accurate and less invasive tools. Intraoperatively, LUS and IOC are complimentary in detecting CBD stones, while laparoscopic CBDE is commonly and safely performed by surgeons comfortable with advanced laparoscopic techniques. Postoperative ERC is effective with failure of laparoscopic CBDE, surgeon inexperience, and unfavorable anatomy and patient selection. Open CBDE should never be looked upon as a failure, while sphincterotomy, sphincteroplasty, and choledochoenterostomy remain necessary operations for certain patients. The proposed algorithm is only a guideline, and ultimate treatment depends on physician experience and available resources.
Interhemispheric connections in neonatal owl monkeys (Aotus trivirgatus) and galagos (Galago crassicaudatus)

Interhemispheric connections were studied by injecting a mixture of horseradish peroxidase (HRP) and wheatgerm agglutinin conjugated with horseradish peroxidase (WGA-HRP) into multiple sites in dorsolateral occipital and parietal cortex of one cerebral hemisphere of three galagos (Galago crassicaudatus) and two owl monkeys (Aotus trivirgatus) within seven days of birth. Cortex was either separated from the rest of the brain, flattened and cut parallel to the surface to aid reconstructing surface-view patterns of labeled neurons and processes, or cut in standard coronal or parasagittal planes to better reveal laminar patterns of connections. In both primate species, the surface-view pattern of callosal connections in infants was remarkably adult-like. In infant owl monkeys, callosal connections were concentrated along the margin of area 18 with area 17, and only a few labeled cells were found within area 17. Other visual areas including the second visual area, V-II, and the middle temporal visual area, MT, had patchy distributions of labeled neurons that extended over large parts of the visual field representations. Primary motor, auditory, and somatosensory fields also had patchy distributions of labeled neurons, with regions of areas 3b and adjoining somatosensory fields having few callosal connections in portions that appeared to correspond with representations of the hand and foot. Results were very similar in galagos, except that newborn galagos, as in adults, had a patchy distribution of callosally projecting neurons that extended well within area 17. Furthermore, the labeled neurons were concentrated in patches that aligned with the cytochrome oxidase blobs of area 17. Finally, callosal connections were concentrated in cytochrome oxidase poor regions of area 3b.
Dissolved organic matter inhibition of sonochemical degradation of aqueous polycyclic aromatic hydrocarbons.

Abstract Sonochemical degradation of aqueous polycyclic aromatic hydrocarbons (PAHs) was found to be rapid in the absence of other dissolved compounds (k=0.006–0.015 s−1). In the presence of 20 mg C l−1 fulvic acid, first-order PAH degradation rate constants decreased from 2.3- to 3.7-fold. Similar results were obtained with added benzoic acid, a crude analog for fulvic acid. In natural waters, PAH degradation was almost completely inhibited. Analysis of the kinetic behavior and reaction products indicates that PAHs are most likely degraded through a radical cation mechanism. Hydroxyl radical appeared to play an insignificant role in the degradation. Inhibited degradation was probably the result of either altered cavitation processes or isolation of the PAH away from cavitation sites.
Inherited behaviour and reactions to drugs

Drugs and the Inheritance of Behavior: A Survey of Comparative Psychopharmacogenetics. By P. L. Broadhurst. Pp. 206. (Plenum: New York and London, 1978.) £12.28.
EPR study of the photoinitiated polymerization of methyl methacrylate

Abstract By means of previously described continuous-flow procedures, we have studied by electron paramagnetic resonance spectroscopy the photolysis of 4,4′-azo-bis-(4-cyanopentanoic acid), R′N: NR′, in solution at 25° and 40°, the two solvents used being toluene and methyl methacrylate, MMA, each containing 8 v/v% N,N-dimethylformamide, DMF. With the use of the first solvent mixture, only the EPR signal of the R ·′radical, CH 3 Ċ(CN)CH 2 CH 2 COOH, was observed; with the use of the second, the absorption was consistent with the presence of two species: a minor component, R ·′, and a major component, addition radicals of structure with n ⩾ 0. These results are analogous to those previously reported for similar studies of the photolysis of 2,2′-azo-bis-(2-methylpropionitrile), RN: NR in toluene and in M MA. In particular, at a given temperature, the spectroscopic properties of the addition-radical component observed in each study were the same in every significant detail. In a like fashion, the photolysis of RN: NR in toluene and MMA, both neat and containing 8 v/v% DMF, has been investigated at 25° and 40°. The results were essentially the same as those found for the previously reported RN: NR investigations employing neat toluene and MMA, so demonstrating the presence of the DMF to cause no appreciable effect on the spectroscopic properties of the R · radical, CH 3 Ċ(CN)CH 3 , or the addition radical .
Imaging synaptic zinc: promises and perils.

It is well established that some excitatory nerve terminals have high concentrations of Zn 2+ in their synaptic vesicles. For some time, it has been believed that synaptic Zn 2+ is released during neurotransmission and acts as a neuromodulator. Fluorescent Zn 2+ indicators that do not penetrate membranes offer the prospect of rendering the release of Zn 2+ visible. Here, I take a critical look at fluorimetric imaging experiments devised to determine whether Zn 2+ is released and show that they are particularly susceptible to artifacts. Moreover, I will argue that recent experiments suggest that, rather than being released, Zn 2+ is presented to the extracellular space firmly coordinated to presynaptic macromolecules.
Emotional responses to child sexual abuse: a comparison between police and social workers in Hong Kong.

Abstract Objective: Research on specific emotional responses of professionals to child sexual abuse (CSA), other than the overwhelming feeling, is currently lacking in the child welfare literature. This study examines the initial responses to CSA of police and social workers in Hong Kong. Method: Based on their recall of the first child sexual abuse incident, 28 police officers and 86 social workers from 10 training sessions on child sexual abuse in Hong Kong indicated how strong they felt about their emotions in 10 categories of 37 responses. Results: Among the 37 emotional responses, police and social workers showed significant differences in only seven responses: (1) embarrassment with the perpetrator; (2) ambivalence about rescuing the child or preserving the family; (3) fear of being inadequate in handling the situation; (4) titillation in response to our involuntary physiological responses to words and descriptions of sex acts; (5) feelings of revenge because the behavior was bad or immoral; (6) empathy with the child’s condition; and (7) ambivalence about helping or punishing the perpetrator. In both groups, “anger at the perpetrator” and “empathy with the child’s condition” were the most strongly felt emotions. Conclusions: Although these two professional groups were not significantly different in most of the emotional responses to their first child sexual abuse incidents, police were more likely to have ambivalent and revenge feelings, while social workers were more likely to have discomfort feelings. Limitations of this research project include sampling procedure, self- report biases, and effect of training.
Combined balloon stent technique with the Scepter C balloon and low-profile visualized intraluminal stent for the treatment of intracranial aneurysms

Background The ‘balloon-then-stent’ method involves stent placement after completion of a balloon-assisted embolization. The drawback to this technique is that the coil mass achieved during balloon remodeling must be crossed prior to stent deployment. This additional maneuver introduces the potential risk of coil disruption. We describe the first report of a novel technique employing the ‘balloon-then-stent’ method. Methods A 51-year-old patient with an unruptured right middle cerebral artery bifurcation aneurysm was treated with balloon remodeling employing a 4×10 mm Scepter C balloon catheter. Following coil embolization, a low-profile visualized intraluminal stent (LVIS) Jr 2.5 mm×16 mm was delivered via the coaxial balloon catheter and deployed across the aneurysm neck. Results Follow-up angiograms demonstrated that the coil mass was well-seated within the aneurysm sac and the parent vessel was widely patent with satisfactory vessel wall apposition by the stent. Conclusions We describe a technique for balloon remodeling followed by stenting for aneurysm coil embolization that incorporates the use of a coaxial dual-lumen balloon catheter system through which a novel self-expanding stent can be deployed. In the case described, we found this technique to be safe and feasible, reducing both the number of steps involved in this technique and the opportunities for mechanical coil-related complications.
Non-kinetic losses caused by electrochemical carbon corrosion in PEM fuel cells

Abstract This paper presented non-kinetic losses in PEM fuel cells under an accelerated stress test of catalyst support. A cathode with carbon-supported Pt catalyst was prepared and characterized during potential hold at 1.2 V vs. SHE in a PEM fuel cell. Irreversible losses caused by carbon corrosion were evaluated using a variety of electrochemical characterizations including cyclic voltammetry, linear sweep voltammetry, electrochemical impedance spectroscopy, and polarization technique. Ohmic losses at the cathode during potential hold were determined using its capacitive responses. Concentration losses in the PEM fuel cell were analyzed in terms of Tafel behavior and thin film/flooded-agglomerate dynamics.
Slow de‐trapping of minority holes in n‐type 4H‐SiC epilayers

The carrier lifetime in epilayers of n-type 4H-SiC with low concentrations of the Z1/2 lifetime killer has been investigated over a wide range of temperature under low injection conditions. It was found that in addition to the primary initial decay dominated by surface recombination (SR), as determined by previous work, in some samples a slow decay component is observed, exhibiting a thermally activated recombination rate. Such a slow tail on the carrier decay can be of concern in high voltage switching devices. The slow decay was well accounted for by the thermal emission of minority carriers trapped on a defect. The resulting analysis has determined that the responsible trap is located ≈Ev + (0.37–0.58) eV with relatively small capture cross-sections for both electrons and holes: σp ≈ (0.5–12) × 10−17 cm2; σn < (0.3–8) × 10−18 cm2. Comparing these characteristics with reports in the literature for as-grown materials, the most likely candidates for the responsible defects are the D- and/or i-centers, which have similar ionization energies and capture cross-sections.
Variability and moral phenomenology

Many moral philosophers in the Western tradition have used phenomenological claims as starting points for philosophical inquiry; aspects of moral phenomenology have often been taken to be anchors to which any adequate account of morality must remain attached. This paper raises doubts about whether moral phenomena are universal and robust enough to serve the purposes to which moral philosophers have traditionally tried to put them. Persons’ experiences of morality may vary in a way that greatly limits the extent to which moral phenomenology can constitute a reason to favor one moral theory over another. Phenomenology may not be able to serve as a pre-theoretic starting point or anchor in the consideration of rival moral theories because moral phenomenology may itself be theory-laden. These doubts are illustrated through an examination of how moral phenomenology is used in the thought of Ralph Cudworth, Samuel Clarke, Joseph Butler, Francis Hutcheson, and Soren Kierkegaard.
Neurodegeneration Induced by PVC-211 Murine Leukemia Virus Is Associated with Increased Levels of Vascular Endothelial Growth Factor and Macrophage Inflammatory Protein 1α and Is Inhibited by Blocking Activation of Microglia

PVC-211 murine leukemia virus (MuLV) is a neuropathogenic retrovirus that has undergone genetic changes from its nonneuropathogenic parent, Friend MuLV, that allow it to efficiently infect rat brain capillary endothelial cells (BCEC). To clarify the mechanism by which PVC-211 MuLV expression in BCEC induces neurological disease, we examined virus-infected rats at various times during neurological disease progression for vascular and inflammatory changes. As early as 2 weeks after virus infection and before any marked appearance of spongiform neurodegeneration, we detected vessel leakage and an increase in size and number of vessels in the areas of the brain that eventually become diseased. Consistent with these findings, the amount of vascular endothelial growth factor (VEGF) increased in the brain as early as 1 to 2 weeks postinfection. Also detected at this early disease stage was an increased level of macrophage inflammatory protein 1α (MIP-1α), a cytokine involved in recruitment of microglia to the brain. This was followed at 3 weeks postinfection by a marked accumulation of activated microglia in the spongiform areas of the brain accompanied by an increase in tissue plasminogen activator, a product of microglia implicated in neurodegeneration. Pathological observations at the end stage of the disease included loss of neurons, decreased myelination, and mild muscle atrophy. Treatment of PVC-211 MuLV-infected rats with clodronate-containing liposomes, which specifically kill microglia, significantly blocked neurodegeneration. Together, these results suggest that PVC-211 MuLV infection of BCEC results in the production of VEGF and MIP-1α, leading to the vascular changes and microglial activation necessary to cause neurodegeneration.
TRACE: Zero-Down-Time Database Damage Tracking, Quarantine, and Cleansing with Negligible Run-Time Overhead

As Web services gain popularity in today's E-Business world, surviving DBMSs from an attack is becoming crucial because of the increasingly critical role that database servers are playing. Although a number of research projects have been done to tackle the emerging data corruption threats, existing mechanisms are still limited in meeting four highly desired requirements: near-zero-run-time overhead, zero-system-down time, zero-blocking-timefor read-only transactions, minimal-delay-timefor read-write transactions. In this paper, we propose TRACE, a zero-system-down-time database damage tracking, quarantine, and recovery solution with negligible run time overhead. TRACE consists of a family of new database damage tracking, quarantine, and cleansing techniques. We built TRACE into the kernel of PostgreSQL. Our experimental results demonstrated that TRACE is the first solution that can simultaneously satisfy the first two requirements aforementioned and the first solution that can satisfy all the four requirements.
Erratum: Complete photon conversion in backward-travelling-wave parametric amplification and oscillation

The condition of complete photon conversion is analysed. It is shown that complete conversion of the pump at finite pump excitation is impossible in forward-travelling-wave signal amplification, but possible in backward-travelling-wave signal amplification.
Challenges for Building Complex Real-time Computing Systems

In the early years of computing, real-time systems consisted of single computers interfaced to a few sensors and effectors, and perhaps to a user control device as well. While such systems still exist, and have become almost ubiquitous in a myriad of everyday devices, the world of real-time computing has expanded in scope and complexity in ways comparable to the proliferation of computers for many other aspects of business, economic and social life. Perhaps the most recent evidence of this expansion is the employment of distributed processing to achieve the objectives of real-time system designers. With the expanded use of computers, particularly in distributed real-time embedded systems (DREs), issues of complexity have emerged that were not faced by early real-time system designers. Ccomplex aggregations of computers operating as a distributed system have assumed a distinctly different character from early real-time systems, exhibiting far more variation in form as well as in the underlying technology base. Dealing with this complexity has become a major driver for innovation in both system architecture and computing technology. The challenge designers face today is, how to design, build, deploy and maintain ever larger and more capable distributed real-time embedded systems to meet the demands of a changing world. Modern real-time systems are likely to be more than just systems; they are rapidly becoming large-scale systems of systems. Because of their long life and high cost, complex real-time systems cannot be recreated as new starts when new requirements emerge. They must evolve and undergo changes and upgrades in place. Furthermore, since the technology base on which DREs are built is changing rapidly, complex real-time systems must allow for the convenient insertion of new computing equipment and supporting software products. For these reasons, flexibility of design has become a paramount concern. This paper will present major challenges and promising solutions for the problem of building real-time open architectures. Based on our experience within the Navy shipboard computing systems domain, we will consider technical characteristics, change management, system flexibility and dynamic resource management.
The Frequency of Osteoporosis Screening in Men With Inflammatory Bowel Disease

Osteoporosis is underdiagnosed in men, and osteoporosis-related fractures carry high morbidity and mortality. Recent recommendations on osteoporosis screening in men from the American College of Physicians state that screening and risk factor assessment need to occur earlier in men at high risk. Men with inflammatory bowel disease are at high risk for osteoporosis and fragility fractures due to corticosteroid use, malabsorption from intestinal resection, potential vitamin D deficiency, and fluctuations in weight. This study examines the rate of corticosteroid use, vitamin D screening, and bone mineral density screening of men with inflammatory bowel disease in a gastroenterology practice. The vast majority of men with inflammatory bowel disease are at high risk for osteoporosis. Screening and risk factor assessment should be emphasized.
Sediment Toxicity from Copper in the Torch Lake (MI) Great Lakes Area of Concern

Abstract Torch Lake (MI) is a Federal Superfund Site and a Great Lakes Area of Concern. Torch Lake was impacted by over 200 million tons of copper rich mine tailings that were deposited in and along the shores of the lake. Twenty percent of the volume of the lake was displaced and the sediments have high concentrations of copper (1,000 mg/kg dry weight on average). Pore water from four sediment cores was analyzed at incremental depths for copper, total organic carbon, and toxicity using the Microtox ® 90% Comparison Test. Cores were also analyzed for copper and organic matter in the dry sediments. Statistical evaluation of data indicated that the upper sediments compared to the deeper sediments: 1) were less toxic (49% light loss versus 68%); 2) contained less pore water copper (0.59 mg/L vs. 0.81 mg/L); 3) had a higher percent organic matter (2.2% vs. 1.6%); and, 4) had no difference in the solid phase copper concentrations. Further evaluation of the sediment toxicity through direct comparison to copper chloride standards demonstrated that all pore water samples had reduced toxicity. The reduced toxicity of the pore water samples was reproduced by adding synthetic organic carbon to the copper chloride standards. These findings have implications for the EPA's No Action alternative for the sediments of Torch Lake. In making their recommendation, the EPA cites that preliminary data (believed to be obtained from nearby Portage Lake) shows that the sediments of Torch Lake are being covered and detoxified by natural sedimentation. However, total copper concentrations in the sediments from the south basin of Torch Lake do not indicate that the sediments are being covered and diluted by natural organic matter laden particles. Also, detoxification may be difficult to demonstrate without a baseline of sedimentation readings for comparison. In fact, solid phase copper concentrations may remain high due to scouring and erosion of surrounding stamp sand beaches or the steep side walls of the lake. This instability of particles has important implications for future restoration and monitoring activities in Torch Lake.
A Longitudinal Analysis of the Competitive Profile of Products and Associated Marketing Practices of Selected European and Non‐European Countries

Internationalisation is a pervasive force in business today and the marketing manager must understand the needs of consumers in various markets. This study explores the general attitudes of Finnish consumers to products made in England, France, West Germany, Japan and the US. Following up earlier surveys of 1975 and 1980 the 1985 data show most positive responses towards products of West Germany and Japan, also highlighting ways in which product attributes and marketing practices can be improved.
Comment on "Dynamic response to heat--a novel physical characteristic of breast cancer".

Song et al.1 report very interesting findings regarding dynamic thermal response of breast cancers. As authors discuss, this finding requires further investigations in other solid tumours and breast cancer for potential clinical applications. One such area for potential clinical application and in need of rather urgent investigation is oesophageal adenocarcinoma and Barret’s oesophagus. Incidence of oesophageal adenocarcinoma is rising rapidly and the accuracy of endoscopic biopsy, even with newer techniques,3,4 is limited in a common premalignant condition of Barrett’s oesophagus. No doubt that further investigation to optimise hot air temperature and duration of heating will be required; but this novel finding raises a distinct possibility of improving accuracy of endoscopic biopsy in Barrett’s oesophagus while simultaneously overcoming some of the associated difficulties (like magnification required) of these newer techniques.
Clustering analysis of microarray gene expression data by splitting algorithm

A clustering method based on recursive bisection is introduced for analyzing microarray gene expression data. Either or both dimensions for the genes and the samples of a given microarray dataset can be classified in an unsupervised fashion. Alternatively, if certain prior knowledge of the genes or samples is available, a supervised version of the clustering analysis can also be carried out. Either approach may be used to generate a partial or complete binary hierarchy, the dendrogram, showing the underlying structure of the dataset. Compared to other existing clustering methods used for microarray data analysis (such as hierarchical and K-means), the method presented here has the advantage of much improved computational efficiency while retaining effective separation of data clusters under a distance metric, a straightforward parallel implementation, and useful extraction and presentation of biological information. Clustering results of both synthesized and experimental microarray data are presented to demonstrate the performance of the algorithm.
Both Neutralization Resistance and High Infectivity Phenotypes Are Caused by Mutations of Interacting Residues in the Human Immunodeficiency Virus Type 1 gp41 Leucine Zipper and the gp120 Receptor- and Coreceptor-Binding Domains

Neutralization resistance of human immunodeficiency virus type 1 (HIV-1) is a major impediment to vaccine development. We have found that residues of HIV-1 MN strain in the C terminus of gp120 and the leucine zipper (LZ) region of gp41 viral envelope proteins interact cooperatively to determine neutralization resistance and modulate infectivity. Further, results demonstrate that this interaction, by which regions of gp120 are assembled onto the LZ, involves amino acid residues intimately related to those which participate in the binding of the envelope to its receptor and coreceptor. Variations in this critical assembly structure determine the concordant, interdependent evolution of increased infectivity efficiency and neutralization resistance phenotypes of the envelopes. The results elucidate important structure-function relationships among epitopes that are important targets of vaccine development.
Use of endoscopic ultrasound to guide combination medical and surgical therapy for patients with Crohn's perianal fistulas.

Background: This study was performed to assess if using endoscopic ultrasound (EUS) to assess and guide combination medical and surgical therapy during fistula healing will lead to a high rate of durable fistula closure and a low or absent incidence of perianal abscess formation in patients with Crohn's perianal fistulas. Methods: This is a retrospective analysis of 21 patients who presented with a symptomatic Crohn's perianal fistula. Patients were enrolled in a clinical practice protocol of serial EUS exams. All patients underwent a baseline rectal EUS and were placed on maximal medical treatment with 6-mercaptopurine (6-MP) or azathioprine, Cipro, and infliximab (5 mg/kg at 0, 2, and 6 wk and then every 8 wk). Patients were also assessed at baseline by a colorectal surgeon who was aware of the EUS findings. Seton placement and incision and drainage were performed when appropriate. Serial EUS examinations were performed, and the findings were used to guide therapy (i.e., the presence of fistula healing on EUS was used to guide seton removal, discontinuation of infliximab, and Cipro). Results: In the 21 patients enrolled, the median duration of active perianal symptoms was 9 wks (1-36). 10 patients (48%) had previous perianal surgery and 5 (24%) had received infliximab previously. The fistulas treated included 8 trans-sphincteric, 2 superficial, 3 recto-vaginal, and 7 with multiple and horseshoe fistulas. 13 patients (62%) had associated abscesses at presentation. Eighteen of 21 patients (86%) had complete cessation of drainage initially. Median time to cessation of drainage was 10.6 weeks (range, 4-32 wk). Sixteen of 21 patients (76%) maintained long-term cessation of drainage. The median length of follow-up was 68 weeks (range, 35-101 wk). No abscess developed during treatment in any patient. EUS evidence of persistent fistula activity was seen in 10 patients (48%). Of the 11 patients (52%) in whom EUS showed no persistent fistula activity, 7 (64%) have maintained fistula closure off of infliximab and Cipro. Median duration from last infliximab infusion was 47 weeks (range, 20-80 wk). The remaining 4 patients continued infliximab to maintain remission of their luminal disease. Only 1 patient with a horseshoe fistula showed complete healing on EUS. Conclusion: In conclusion, using EUS to guide therapy for Crohn's perianal fistulas with infliximab, an immunosuppressive, and an antibiotic is associated with a high short and long-term fistula response rate. EUS may identify a subset of patients who can discontinue infliximab without recurrence of fistula drainage.
FET active slotline notch antennas for quasi-optical power combining

A new active antenna structure with applications in quasi-optical power combining is described. The active antenna combines a slotline FET oscillator with a notch antenna. The new structure was successfully used to create both E-plane and H-plane linear arrays as well as a 2D array. Preliminary results of radiation patterns and the power combining efficiencies of the arrays are discussed. >
Survival and Cause-Specific Mortality of Neonatal Mule Deer Fawns, North-Central New Mexico

Abstract Because of significant declines in mule deer (Odocoileus hemionus) populations across New Mexico, USA, we investigated survival of fawns in north-central New Mexico, USA. We captured 19 fawns, 34 fawns, and 47 fawns in 2002, 2003, and 2004, respectively, and used fawn morphological measurements, habitat characteristics, and adult female (hereafter “female”) condition to model preweaning fawn survival. Survival was 0.0, 0.12, 0.52 for 2002, 2003, and 2004, respectively, and was related to birth mass (χ12 = 9.5, P = 0.002), birth date (χ12 = 8.4, P = 0.004), litter size (χ22 = 9.4, P = 0.009), female body fat (χ12 = 40.9, P < 0.001), annual precipitation (χ12 = 35.0, P < 0.001), summer precipitation (χ12 = 37.5, P < 0.001), and winter precipitation (χ12 = 32.0, P < 0.001). Total ingesta-free body fat of females (β = 3.01, SE = 0.75; odds ratio = 20.19, 95% CI = 4.64–87.91) and birth mass of fawns (β = 1.188, SE = 0.428; odds ratio = 3.38, 95% CI = 1.42–7.59) were the best predictors of survival of ...
Software evolution in agile development: a case study

The agile development method (ADM) is characterized by continuous feedback and change, and a software system developed using ADMevolves continuously through short iterations. Empirical studies on evolution of software following agile development method have been sparse. Most studies on software evolution have been performed on systems built using traditional (waterfall) development methods or using the open source development approach. This paper summarizes our study on the evolution of an enterprise software system following ADM. We evaluated key characteristics of evolution in the light of Lehman's laws of software evolution dealing with continuous change and growth, self-regulation and conservation, increasing complexity and declining quality. Our study indicates that most laws of evolution are followed by the system. We also present our observations on agile practices such as collective code ownership, test driven development and collaboration when the team is distributed.
Omega-conotoxin sensitivity and presynaptic inhibition of glutamatergic sensory neurotransmission in vitro.

Synaptic transmission between embryonic chick dorsal root ganglion (DRG) neurons and spinal cord neurons was studied in dissociated cell culture. Stimulation of DRG neurons evoked monosynaptic and polysynaptic excitatory responses in the spinal neurons. These responses could be reversibly blocked by application of 6-cyano-7- nitroquinoxaline-2,3-dione (a selective non-NMDA receptor antagonist) and irreversibly eliminated through the presynaptic action of omega- conotoxin GVIA (a selective N-type calcium channel antagonist). As N- type calcium channels in DRG neuron somata are targets for modulation via GABAB receptors, we tested the role of these receptors as regulators of synaptic transmission. Baclofen (a selective GABAB receptor agonist) reversibly inhibited synaptic transmission via a presynaptic, pertussis toxin-sensitive mechanism; CGP 35348 (a selective GABAB receptor antagonist) blocked the actions of baclofen. Taken together, these results demonstrate that N-type calcium channels play a dominant role in glutamatergic sensory neurotransmission. They suggest, in addition, that modulation of N-channel activity may underlie, at least in part, presynaptic inhibition of synaptic transmission between DRG neurons and their targets in the intact spinal cord.
Use of digital media technology for primary prevention of STIs/HIV in youth.

Abstract Study Objective The relevant literature was reviewed to identify issues in research evaluating digital media technology (DMT) interventions for the primary prevention of STIs/HIV in adolescents and young adults. Method A literature search with relevant key terms was conducted in PubMed, for articles with studies that included: (a) participants between 11-29 years; (b) use of one or more of the following forms of DMT: interactive digital video or CD-ROM, computer, text messaging, or Internet; (c) evaluation of an STI/HIV primary prevention intervention; and (d) use of a cognitive, psychosocial, behavioral, or biological outcome. Results Twenty-nine studies were identified and included in the review. Based on the review of these studies, 7 main issues were discussed and recommendations for improving future research were offered. The 7 main issues were: (a) need for a balance between universal application and specific sub-group focus, (b) lack of a developmental framework, (c) challenge of applying DMT in resource limited contexts, (d) rapidly changing nature of DMT, (e) lack of biological outcomes, (f) lack of comparison/control groups to assess the impact of DMT, and (g) limited temporal follow-up. Conclusions There is increasing literature evaluating the effectiveness of DMT for preventing STIs/HIV among adolescents and young adults. A careful consideration of 7 main issues identified in the literature can improve the design and evaluation of these interventions and enhance our understanding of their effectiveness.
Mobile robot exploration and map-building with continuous localization

Our research addresses how to integrate exploration and localization for mobile robots. A robot exploring and mapping an unknown environment needs to know its own location, but it may need a map in order to determine that location. In order to solve this problem, we have developed ARIEL, a mobile robot system that combines frontier based exploration with continuous localization. ARIEL explores by navigating to frontiers, regions on the boundary between unexplored space and space that is known to be open. ARIEL finds these regions in the occupancy grid map that it builds as it explores the world. ARIEL localizes by matching its recent perceptions with the information stored in the occupancy grid. We have implemented ARIEL on a real mobile robot and tested ARIEL in a real-world office environment. We present quantitative results that demonstrate that ARIEL can localize accurately while exploring, and thereby build accurate maps of its environment.
Preparation of targets for nuclear chemistry experiments at DANCE

In this paper, we describe the separation chemistry and electrodepositions conducted for the preparation of 241Am, 243Am and 233U targets used for cross-section measurements at DANCE. Thick, adherent deposits were prepared using molecular plating from isopropyl alcohol solutions. Improved yields and thicknesses were observed for 241Am electrodeposition after the material was purified using TRU resin from Eichrom. Similarly, 233U deposits were improved after purification with an anion exchange column in 9 M HBr followed by purification using UTEVA resin from Eichrom.
Individual and Population Effects of Eugregarine, Gregarina niphandrodes (Eugregarinida: Gregarinidae), on Tenebrio molitor (Coleoptera: Tenebrionidae)

Gregarines are single-celled parasites in the phylum Apicomplexa that infect invertebrates. They are highly abundant on three levels: among a large diversity of invertebrates, in the proportion of population of organisms they infect, and within individually infected organisms. Because of their remarkable prevalence, we hypothesize that they play an important role in support of their hosts. However, studies done to date on the impact of gregarines on their host are conflicting. Therefore, we studied the impact of gregarines on their host using a model Gregarina niphandrodes infection in Tenebrio molitor. The impact of infection was measured by comparing beetles with no or low infection to those with artificially induced high infection. The numbers of individuals in each of the three easily visible developmental stages of the T. molitor (larva, pupa, and adult) were censused weekly. From these observations, fertilities and probabilities of survival with transition between stages were estimated. These estimated vital rates were used to construct a stage-classified projection matrix model. We also measured the longevity of individual beetles with low and high infection that were grown in isolation. The results indicate that there is no significant difference in the population dynamics of beetles with low and high infection. However, the longevity was significantly different between beetles with low infection than the deliberately highly infected group.
A Q3-Based Permutation Test for Assessing Local Independence

Item response theory (IRT) is a powerful statistical methodology used in the analysis of psychological and educational assessments. IRT rests on three fundamental assumptions about the data, including local independence, which means that after accounting for the latent trait(s) being measured, the item responses are independent of one another. Traditionally, this assumption is assessed using Yen's Q3 statistic. However, Q3 does not have a known sampling distribution, and thus, it is typically used in a descriptive fashion, such that values larger than an arbitrary cut-value (e.g., 0.2) indicate the presence of local dependence. The current study introduces a formal test of the null hypothesis that for a given item pair Q3 is 0, based on permutation test methodology. A small simulation study carried out to assess the Type I error and power rates of the Q3 permutation test found that this new statistic maintains good Type I error control, while also yielding power for detecting local dependence at a rate higher than that associated with the use of the 0.2 cut-value.
Event-enabled intelligent asset selection and grouping for photobook creation

The process of creating a photo product, such as a photobook, calendar or collage, from a large personal image collection requires intensive user effort. The primary goal of the current research was to develop an end-to-end solution to the problem of photo product generation that enables the user to complete the process with minimal edits, where the system intelligently selects assets and groups them before presenting the output to the user. The automation is driven by metadata extracted both from individual images as well as from sets of assets in a collection. In particular, we use an automatically detected event hierarchy to establish meaningful groupings in the assets, and to determine an appropriate grouping and pagination for the final product. We propose a novel intermediate construct, called a storyboard, which can be translated to different product types without recomputing the underlying metadata. In addition to chronological storyboards, we also describe a novel hybrid storyboard that joins chronological image presentation with groups of images of a common theme. A pagination algorithm uses the information in the storyboard and the product constraints to generate a product. Finally, the user is provided with a metadata-driven editing mechanism that makes it easy to change the auto-populated product. Given that the proposed system envisions user interaction in creating the final product, user studies are conducted to judge the usefulness of the system, where consumers use the system to generate a photobook with their own images. An end-to-end, metadata-driven intelligent system for automatic photobook creationA flexible intermediate story representation for creating multiple product typesAutomatic generation of representations for event-based and theme-based groupingsA new pagination algorithm for mapping selected images onto photobook pagesMetadata-aided UI enabling users to view groupings and find alternative images