cssi/SciSciGPT-SciSciNet huggingface dataset:
High-brightness high-duty cycle electron injectors

Abstract High brightness electron sources have been one of the driving forces behind the spectacular results achieved in the last decade by accelerator-based applications. Indeed, X-Ray FELs, with their 10-fold orders of magnitude increase in peak brightness, probably represent the best example of it. New ambitious proposals for X-ray FELs and ERLs, as well as inverse Compton sources for X- or gamma-ray production, are now requiring operation at MHz-GHz repetition rates. In response to that, a number of groups around the world have been actively working in developing high-brightness high-duty cycle electron injectors capable of driving such machines. The high repetition rate requirement cannot be met by the existing low-repetition rate high-brightness injector schemes, and new technologies are under investigation. This paper includes a description of the requirements for such injectors, an overview of the pursued technologies and schemes, a description of the main beam dynamics issues associated with the different choices, and a number of examples of the results obtained so far by the groups active in the field.
Acetabular fractures following rugby tackles: a case series

Introduction Rugby is the third most popular team contact sport in the world and is increasing in popularity. In 1995, rugby in Europe turned professional, and with this has come an increased rate of injury.
Orthodontic tooth movement during an ascorbic acid deficiency

Abstract The effects of an ascorbic acid deficiency during tooth movement were studied in guinea pigs to determine what morphologic changes could be observed during this vitamin deficiency. Mandibular incisors were moved laterally with an appliance that produced a light, continuous force. In the control animals of Group I, the normal morphologic structures were observed. In the animals of Group II, the effects of the orthodontic appliance were evident. The animals of Group III did not receive ascorbic acid in their diets and changes in the bone and periodontal ligament were observed. The most pronounced changes were seen in the animals of Group IV. This group had the orthodontic appliance and did not receive any ascorbic acid in the diet. Morphologic alterations were observed in the periodontal ligament and surrounding bone. Lack of normal collagen synthesis, because of the lack of ascorbic acid, resulted in an almost complete cessation of osteogenesis and disorganization of the periodontal ligament. It appears that ascorbic acid is necessary for the normal morphology of the peridontal ligament and alveolar bone. This need was accentuated during the application of light forces which placed a stress on the various tissues.
The molecular basis for the regulation of the cap-binding complex by the importins

The binding of capped RNAs to the cap-binding complex (CBC) in the nucleus, and their dissociation from the CBC in the cytosol, represent essential steps in RNA processing. Here we show how the nucleocytoplasmic transport proteins importin-alpha and importin-beta have key roles in regulating these events. As a first step toward understanding the molecular basis for this regulation, we determined a 2.2-A resolution X-ray structure for a CBC-importin-alpha complex that provides a detailed picture for how importin-alpha binds to the CBP80 subunit of the CBC. Through a combination of biochemical studies, X-ray crystallographic information and small-angle scattering experiments, we then determined how importin-beta binds to the CBC through its CBP20 subunit. Together, these studies enable us to propose a model describing how importin-beta stimulates the dissociation of capped RNA from the CBC in the cytosol following its nuclear export.
Cryo-Electron Tomography and Computer Simulations Reveal Distinct CheA Kinase Conformation in Bacterial Chemotaxis Signaling Receptor Complex

Improved sample preparation, data collection, and image processing pipelines have ushered in a new era in cryo-Electron Tomography (CryoET). Electron density maps of large, conformationally heterogeneous assemblies can be determined at subnanometer resolutions and coupled with high resolution structural information and large scale molecular dynamics simulation to gain atomistic understanding of large and complex cellular machinery that is otherwise unattainable. We use such an integrative approach to investigate the signal transduction in bacterial chemotaxis arrays - large transmembrane protein complex assemblies responsible for modulating the motility of bacteria. These arrays are responsible, in part for appropriately biasing the cell's inherent random walk, and also retaining the memory of recent states of the system. Despite recent advances, fundamental questions on how the components of the system work together to transduce the signal from membrane receptor to kinase molecule, and how the individual signaling unit works cohesively to achieve a large gain in signaling remain unanswered. We devised a novel in vitro reconstitution system to build extended signaling arrays on a lipid monolayer using purified protein components, providing an unprecedented number of signaling units in a thin layer (∼150-200nm) ideal for cryoET. The individual subvolumes from 3D tomograms are extracted, aligned, classified and averaged, resulting in a 3D density map of the basic chemotaxis signaling unit comprising the chemoreceptor, the histidine kinase CheA and the cofactor CheW. The density map reveals an unexpected asymmetry among three kinase CheA dimers, indicating distinct CheA conformations within the unit. Large scale all-atom molecular dynamics simulations further point to the specific side chain contacts that mediate the transition of CheA conformations, which we show, through biochemical assays, to fully abrogate chemotactic function if disrupted.
Coastal New England pilot study to determine fossil and biogenic formaldehyde source contributions using radiocarbon

[1] Compound specific radiocarbon analyses of atmospheric formaldehyde are reported as fraction modern (Fm) for a limited number of winter and summer air samples collected in coastal southern New England in 2007. The 11 of 13 samples with Fm 0.2 (max ∼ 0.35) were collected on days with strong northwesterly flow and the least urban impact. The Fm data were combined with VOC observations from the Rhode Island Department of Environmental Management, estimates of oxygenated VOC (OVOC), and back trajectories to interpret the relative contributions of biogenic and fossil carbon sources. It is argued that CH2O sources were dominated by pollutant VOCs and OVOCs from upwind coastal cities as opposed to more local biogenic VOCs at the times of sample collection.
Analysis of linear sampled-data systems with finite pulse width: Open loop

An exact method for analysis of sampled-data systems with finite pulse width is presented. The results make it possible to obtain the output of such systems in a closed form, as a continuous function of time, and without recourse to any approximations. (The closed form is that which does not involve summation of series.) The analysis is based on introducing a new transform method, analogous to the z-transform, except that the actual pulse width and pulse shape are considered. This is called the p-transform where p denotes pulse width. Furthermore, by utilizing the modified z-transform, a method for obtaining the inverse Laplace transform of functions involving both ?Ts and s is developed. This technique has been advantageously applied to evaluate the inverse p-transform in a closed form. (The term ?modified z-transform? was introduced in reference 1.) The limiting cases of the p-transform are investigated. It is concluded that the p-transformation method provides a powerful technique for analysis of sampled-data systems with finite pulse width.
Cerebellar afferents to paramedian lobule from the trigeminal complex in Tupaia glis: a horseradish peroxidase (HRP) study.

Projections from the trigeminal complex to paramedian lobule (PML) were studied in the tree shrew (Tupaia glis) by means of retrograde transport of horseradish peroxidase (HRP). Neurons which project to both dorsal and ventral folia of PML are located primarily in those areas of the trigeminal nuclear complex interpreted as nucleus interpolaris (Vi) and caudal areas of the nucleus oralis (Vo). The majority of HRP-labeled neurons lie in ventral and ventrolateral regions of Vi/Vo. No HRP-reactive cells are present in the principal (Vp), mesencephalic, or motor nuclei nor in nucleus caudalis or rostral portions of oralis. The majority of trigeminocerebellar (TC) cells are found in ipsilateral Vi; however, sparse numbers of labeled somata are present in this subnucleus on the contralateral side. Within Vi/Vo, small fusiform and medium- and large-sized multipolar neurons contain HRP-reaction product. Large multipolar cells are found primarily in ventrolateral portions of Vi/Vo, while medium and small neurons are scattered throughout the ventral half of the nucleus. Small-sized neurons are also present dorsally within Vi/Vo. Axons of labeled TC cells course laterally through the spinal trigeminal tract, enter medial aspects of the restiform body, and arch dorsally into the cerebellum.
Small Cell Carcinoma of the Lung Treated with Irradiation and Chemotherapy: Autopsy Confirmation of Long-Term Disease-Free Survival

A patient survived clinically disease free for 68 months following combination chemotherapy and radiotherapy for small cell carcinoma of the lung. No evidence of tumor was found at autopsy. To our knowledge, this represents the first documentation by autopsy of a greater than five year disease-free survival following treatment of small cell cancer of the lung.
Impedance Measurement of Changes in Activity of Lactic Cheese Starter Culture After Storage at 4°C

Abstract Impedance, titratable acidity, and change in pH were used to measure activity of lactic cheese starter culture held up to 7 d at 4°C. The impedance microbiology, as quantified by the impedance detection time method, provided an activity estimate within 37 to 53min, and the results were similar to the activity measurements using titratable acidity (3.5h) and change in pH (2.5h). The impedance detection time, titratable acidity, and pH activity tests showed that the culture activity decreased most rapidly between 2 and 5 d. The slope of the impedance curve, 15min after the impedance detection time, decreased as storage time increased with the sharpest decrease occurring during the first 3 d of storage.
Designing visualizations of social activity: six claims

In this paper, we describe a set of claims that have evolved from our work in designing visual representations of groups in online environments. We argue that these claims can serve as a good starting point for design work, and can drive critical discussions amongst design stakeholders.
Materials characterization from diffraction intensity distribution in the γ -direction

Two-dimensional X-ray diffraction (XRD2) pattern can be described by the diffraction intensity distribution in both 2θ and γ-directions. The XRD2 images can be reduced to two kinds of profiles: 2θ-profile and γ-profile. The 2θ-profile can be evaluated for phase identification, crystal structure refinement, and many applications with many existing algorithms and software. In order to evaluate the materials structure associated with the intensity distribution along γ-angle, either the XRD2 pattern should be directly analyzed or the γ-profile can be generated by 2θ-integration. A γ-profile contains information on texture, stress, crystal size, and crystal orientation relations. This paper introduces the concept and fundamental algorithms for stress, texture, and crystal size analysis by the γ-profile analysis.
Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading

Eutrophication is a water quality issue in lakes worldwide, and there is a critical need to identify and control nutrient sources. Internal phosphorus (P) loading from lake sediments can account for a substantial portion of the total P load in eutrophic, and some mesotrophic, lakes. Laboratory determination of P release rates from sediment cores is one approach for determining the role of internal P loading and guiding management decisions. Two principal alternatives to experimental determination of sediment P release exist for estimating internal load: in situ measurements of changes in hypolimnetic P over time and P mass balance. The experimental approach using laboratory-based sediment incubations to quantify internal P load is a direct method, making it a valuable tool for lake management and restoration. Laboratory incubations of sediment cores can help determine the relative importance of internal vs. external P loads, as well as be used to answer a variety of lake management and research questions. We illustrate the use of sediment core incubations to assess the effectiveness of an aluminum sulfate (alum) treatment for reducing sediment P release. Other research questions that can be investigated using this approach include the effects of sediment resuspension and bioturbation on P release. The approach also has limitations. Assumptions must be made with respect to: extrapolating results from sediment cores to the entire lake; deciding over what time periods to measure nutrient release; and addressing possible core tube artifacts. A comprehensive dissolved oxygen monitoring strategy to assess temporal and spatial redox status in the lake provides greater confidence in annual P loads estimated from sediment core incubations.
Protective Immunity to Bordetella pertussis Requires Both B Cells and Cd4+ T Cells for Key Functions Other than Specific Antibody Production

To investigate the fundamental nature of protective immunity to Bordetella pertussis, we studied intranasal immunization of adult mice with formalin-fixed B. pertussis (FFBP), followed by aerosol B. pertussis challenge. Mice given two doses of FFBP intranasally completely cleared a subsequent pertussis aerosol challenge from tracheae and lungs (defined as protection), but there was no correlation between levels of specific antibody and clearance of bacteria. Further, transfer of immune serum before aerosol challenge had minimal effects on bacterial burdens. However, pertussis-specific T cells producing interferon γ but not interleukin 4 or interleukin 10 were detected in draining lymph nodes of FFBP-immunized mice. Significantly, repeated immunization of B cell knockout (BKO) mice resulted in partial protection, and complete protection was reconstituted by transfer of pertussis-immune B cells; reconstituted BKO mice had little if any detectable antipertussis antibodies. Immunization of mice lacking all T cells or lacking CD4+ T cells did not lead to protection; in contrast, CD8− mice were protected. Mice depleted of CD4+ T cells after immunization but before aerosol challenge, which thus had normal amounts of specific antibodies, were not optimally protected. Taken together, these data indicate that protective immunity to pertussis is dependent on both CD4+ T cells and B cells, and both cell types provide significant functions other than specific antibody production.
Unfulfilled goals interfere with tasks that require executive functions

Even after one stops actively pursuing a goal, many mental processes remain focused on the goal (e.g., the Zeigarnik effect), potentially occupying limited attentional and working memory resources. Five studies examined whether the processes associated with unfulfilled goals would interfere with tasks that require the executive function, which has a limited focal capacity and can pursue only one goal at a time. In Studies 1 and 2, activating a goal nonconsciously and then manipulating unfulfillment caused impairments on later tasks requiring fluid intelligence (solving anagrams; Study 1) and impulse control (dieting; Study 2). Study 3 showed that impairments were specific to executive functioning tasks: an unfulfilled goal impaired performance on logic problems but not on a test of general knowledge (only the former requires executive functions). Study 4 found that the effect was moderated by individual differences; participants who reported a tendency to shift readily amongst their various pursuits showed no task interference. Study 5 found that returning to fulfill a previously frustrated goal eliminated the interference effect. These findings provide converging evidence that unfulfilled goals can interfere with later tasks, insofar as they require executive functions.
Assessment of trace element geochemistry of Hampton Roads harbor and lower Chesapeake Bay area sediments

Acid extractable Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb. and Zn were determined in sediments from the Inner Virginia Shelf, and from shipping channels in the lower Chesapeake Bay and Hampton Roads, Virginia, harbor system. Data were evaluated by a variety of techniques Levels of Cd, Cu, Pb, and Zn exceeded average crustal abundances for most of the study sites. Cumulative frequency curves suggested that there were two major populations for all metals and perhaps a third and smaller, one for Cd, Cr, and Mn Plots of metal vs Fe indicated no anthropogenic inputs of metals for shelf and Chesapeake Bay channel sites, but suggested anthropogenic influences for all metals in several of the inshore sites. Enrichment factor calculations showed enrichment of Cd, Pb, and Zn with respect to average crustal abundances for all sites and of Cu for the industrial harbor system. A recommendation of this study for evaluation of environmental geochemical metals data is to utilize mean concentrations, cumulative frequency plots, and metal vs Fe and/or enrichment factor calculations when evaluating the pollution status of sediments.
Development of a Water Runoff Model for Pakistan: A tool for Identifying and Assessing Micro-hydro Sites

A hydrologic model for basins draining through Pakistan is developed with the specific intent of identifying micro-hydro sites and assessing their quality. The model outputs runoff which is used to estimate flow rate through each geographic cell. These flow rates are scaled by topographic slope using a relationship for potential power to approximate micro-hydro productivity on a cell-by-cell basis. A major hindrance in building and applying models to the region is the lack of dense and consistent meteorological data. This is partially ameliorated by downscaling the data, which improves both its resolution and ability to represent the underlying processes. This study compares the Delta and Bias Correction-Spatial Disaggregation (BCSD) downscaling methods, ultimately using the meteorological time-series data produced through the Delta method as inputs to the hydrological model. Results are given in normalized form as a demonstration of the model's utility for assessing potential micro-hydro site quality. Future work will include analysis of past and future trends in runoff, where future meteorological scenarios will be based upon the emissions paths developed by the Intergovernmental Panel on Climate Change.
Interplanetary diffusion model for the time behavior of intensity in a solar cosmic ray event

The time history of the intensity of several solar cosmic ray events can be interpreted in terms of a unified interplanetary diffusion model which assumes that the diffusion coefficient D = Mrβ, where r is the heliocentric radial distance and M and β are parameters, which may be dependent on particle energy E. The model is particularly successful in accounting for the decay phases. For the September 28, 1961, event M varies as E0.33, and, assuming spherical geometry, β is equal to 1 for 55<E<500 Mev and decreases rapidly at lower energies. At r = 1 AU the mean free path λ is about 0.081 AU for E ∼200 Mev and 0.15 for E = 23 Mev. The energy dependences of β and λ suggest 0.006 AU as the order of magnitude of the scale size of irregularities in the interplanetary magnetic field. The source spectrum is inferred. The possibility of nonspherical geometry of diffusion is considered, as is the implication of the results with respect to the solar modulation of galactic cosmic radiation.
Human Prk Is a Conserved Protein Serine/Threonine Kinase Involved in Regulating M Phase Functions

Human prk encodes a novel protein serine/threonine kinase capable of strongly phosphorylating casein but not histone H1 in vitro. prk expression is tightly regulated at various levels during different stages of the cell cycle in lung fibroblasts. The Prk kinase activity is relatively low during mitosis, G1, and G1/S, and peaks during late S and G2 stages of the cell cycle. Recombinant human Prk expressed through the baculoviral vector system is capable of phosphorylating Cdc25C, a positive regulator for the G2/M transition. Human prk shares significant sequence homology with Saccharomyces cerevisiae CDC5 and Drosophila melanogaster polo, both of which are essential for mitosis and meiosis. Full-length prk transcripts greatly potentiate progesterone-induced meiotic maturation of Xenopus laevisoocytes. On the other hand, antisense prk transcripts significantly delay and reduce the rate of oocyte maturation. When expressed in a CDC5 mutant strain of S. cerevisiae, human Prk, but not a deletional mutant protein, fully rescues the temperature-sensitive phenotype of the budding yeast. Taken together,prk may represent a new protein kinase, playing an important role in regulating the onset and/or progression of mitosis in mammalian cells.
Loss of Heterozygosity in Human Ovarian Cancer on Chromosome 19q

Abnormalities in the function of oncogenes and tumor suppressor genes have been associated with many human malignancies. The recognition of sites of loss of heterozygosity (LOH) has led to the identification of such genes. We previously reported that abnormalities of mRNA expression of ERCC1 and ERCC2 may be characteristic of epithelial ovarian carcinoma and brain tumors. This led to an investigation of chromosome 19q13.2-q13.4 which contains these DNA repair genes. A 7-Mb region was analyzed using six microsatellite repeats. Loss of heterozygosity has been identified in 53% (8/15) of cases at marker D19S246 which lies in a 2-Mb segment between HRC and KLK1. The genetic material both centromeric and telomeric to the region of loss was conserved. This area is telomeric to three DNA repair genes where LIG1 is 1-Mb centromeric and ERCC1 and ERCC2 are 3.5- and 4.0-Mb centromeric, respectively. These findings represent the first report of a biologically significant rate of LOH on chromosome 19q13.2-q13.4 in human ovarian carcinoma.
Catalytic Reduction of 1,1,1-Trichloro-2,2,2-trifluoroethane (CFC-113a) by Cobalt(I) Salen Electrogenerated at Vitreous Carbon Cathodes in Dimethylformamide

Catalytic reduction of 1,1,1-trichloro-2,2,2-trifluoroethane (CFC-113a or Freon 113a) by cobalt(I) salen electrogenerated at a carbon cathode in dimethylformamide (DMF) containing 0.10 M tetramethylammonium tetrafluoroborate (TMABF 4 ) has been investigated with the aid of cyclic voltammetry, controlled-potential electrolysis, gas chromatography-mass spectrometry, and high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS). Cyclic voltammetry reveals that CFC-113a and two of its degradation products, 2,2-dichloro-l,l,l-trifluoroethane (HCFC-123) and 2-chloro-1,1,1-trifluoroethane (HCFC-133a), can all undergo catalytic reduction by cobalt(I) salen. Controlled-potential (bulk) electrolyses of cobalt(II) salen in the presence of CFC-113a lead to the production of HCFC-123, HCFC-133a, 2-chloro-l,l-difluoroethene (HCFC-1122), and 1,1-difluoroethene (HFC-1132a). HPLC-ESI-MS has been employed to demonstrate that, during the bulk catalytic reduction of CFC- 113a, the salen ligand of the catalyst is modified through addition of a CF 3 CCl 2 - or CF 3 CHCl- moiety to an imino (C = N) bond. On the basis of documented knowledge about the electrochemistry of cobalt-containing complexes, together with the results of our cyclic voltammetry and bulk electrolysis experiments, a mechanistic scheme is proposed for the cobalt(I) salen-catalyzed reduction of CFC-113a.
Positive affect promotes engagement in care after HIV diagnosis

Objective Revised Stress and Coping Theory proposes that positive affect serves adaptive functions and its beneficial effects are heightened during stressful periods. This study examined the prospective relationship between positive affect and engagement in care during the 18 months following a HIV seropositive diagnosis.
Developmental changes in rat diaphragm endplate response to repetitive stimulation

Abstract Endplate potentials (epps) were recorded intracellularly from single diaphragm fibers, in vitro, of newborn (≤ 10 days, n = 10) and older (18–29 days, n = 5) rats with glass microelectrodes. The muscle was stimulated via the phrenic nerve for 1 s at 10, 20 or 50 Hz. Muscle action potentials were blocked by μ conotoxin GIIIA, a specific muscle Na + channel blocker. In diaphragms from older animals, epps followed nerve stimulation at the 3 frequencies, with a gradual decrement in amplitude to 70% of the first epp at 50 Hz. The younger age group showed an initial enhancement of epp amplitude, followed by large variability in amplitude. These data suggest that neuromuscular transmission failure in the newborn diaphragm is secondary to variability in neurotransmitter release as compared to the more mature diaphragm.
Nondetectable plasma glucose levels after insulin administration in the American bullfrog (Rana catesbeiana)

Abstract The effect of a single intraarterial infusion of mammalian insulin on plasma glucose was determined in the American bullforg ( Rana catesbeiana ). Insulin was administered, and blood samples were collected, from an indwelling cannula placed in the sciatic artery. Plasma glucose was estimated by the glucose oxidase method. Control plasma glucose levels were 8.7 ± 0.7 mg/dl at time zero immediately prior to the infusion of the hormone-free carrier solution and were 6.9 ± 1.0 mg/dl on Day 5 when sampling was terminated. The time-zero plasma glucose levels of the bullfrogs that received 15 IU/kg body weight insulin were 10.7 ± 1.0 mg/dl and declined to 0.4 ± 0.1 mg/dl by 12 hr after the infusion. The levels remained severely depressed at 24 hr and then returned to approximately the time-zero levels by Day 3. The initial plasma glucose levels of the animals that received 45 IU/kg body weight insulin were 8.7 ± 0.6 mg/dl. The levels declined to 0.5 ± 0.2 mg/dl by 12 hr, remained severely depressed at Day 2, and then returned to approximately the time-zero levels by Day 4. Convulsions occurred in all of the 45 IU insulin-treated animals and 40% of the bullfrogs died. In contrast, convulsions did not occur in any of the 15 IU insulin-treated bullfrogs and all of the animals survived, although plasma glucose was not detectable in one-half of the bullfrogs at one or more sampling periods between 6 and 24 hr after the infusion. The results support the hypothesis that glucose, in the absence of stress, may not be an essential source of energy in the bullfrog.
Plasma glycosaminoglycans in normal individuals of various age.

Abstract Our previous studies have demonstrated that the high-sulfated glycosaminoglycans (GAG) of human plasma interact with low-density and high-density plasma lipoproteins (LDL and HDL), while the more abundant, low-sulfated plasma GAG prevent such interaction. Therefore, we have suggested that the ratio of these two species of circulating GAG might affect the rheological properties and metabolic fate of plasma lipoproteins. In this study the high-sulfated and low-sulfated plasma GAG have been measured in 79 normal individuals of both sexes, belonging to increasing age groups: 20–29, 30–39, 40–49 and 50–59 years old. No significant differences were found between males and females of the same group. No significant differences were found between the levels of high-sulfated and low-sulfated plasma GAG of the first and second group of individuals. The average values found and their ratios were in agreement with those reported previously for the same age groups. The average values of high-sulfated and low-sulfated plasma GAG of the third and fourth group of individuals were not statistically different but they were significantly higher than those of the first two groups. Moreover, the ratio high-sulfated/low-sulfated plasma GAG in older individuals was between 0.41 and 0.45, as compared to values of 0.27–0.37 found in the younger individuals. This increased ratio reflects a greater increase in the level of the high-sulfated species which, by interacting with circulating lipoproteins, might cause physical and metabolic modifications favoring their deposition and permanence within the arterial wall.
Fast and power-efficient infrared single-photon upconversion using hot-carrier luminescence

We analyze a new method for single-photon frequency upconversion. This technique uses a byproduct of the avalanche process - electroluminescence resulting from hot-carrier recombination - as a means of upconversion. Because the spectrum of the emitted photons peaks near the bandgap of the multiplying material and has a significant tail at higher energies, it is possible to generate secondary photons at significantly higher energies than the primary absorbed photon. The secondary photons can then be detected by a coupled CMOS silicon single-photon avalanche diode (SPAD), where the information can also be processes. This upconversion scheme does not require any electrical connections between the detecting device and the silicon SPAD, so glass-to-glass bonding can be used, resulting in inexpensive, high-density arrays of detectors. We calculate the internal and system upconversion efficiencies, and show that the proposed scheme is feasible and highly efficient for application such as quantum key distribution and near infrared low-light-level imaging.
New technique for characterising diffraction by inhomogeneously filled slot of arbitrary cross-section in thick conducting plane

A new technique that combines the finite-element and boundary-integral methods and employs the conjugate gradient method and fast Fourier transform is presented for the numerical characterisation of electromagnetic scattering by inhomogeneously filled slots of arbitrary cross-section in a thick conducting plane.
Characterization of calcium phosphate powders by ESCA and EDXA

Calcium phosphate (CaP) materials can be well characterized by traditional methods such as wet chemistry and X-ray diffraction (XRD). These methods, however, offer limitations when non-destructive evaluation of CaP coatings on curved surfaces is required. Since the source powders for these coatings are generally commercially available CaP powders, careful characterization of the source powders may allow inferences to be made regarding the effects of plasma spraying on coating composition. Nine commercially available CaP powders were characterized by scanning electron microscopy, wet chemistry and XRD. These techniques showed that major differences exist between individual powders claiming to be hydroxyapatite. Analysis of these nine powders by electron spectroscopy for chemical analysis (ESCA) and energy dispersive X-ray analysis (EDXA) suggest that these techniques can provide the chemical composition of CaP in a non-destructive manner and thus may be of use in determining the composition of CaP in configurations (such as coatings on metal surfaces) not readily amenable to traditional methods. A calibration curve is required, however, to relate this surface chemical composition result to the material's bulk composition as determined by wet chemistry analysis. Errors of less than 10% can be obtained using ESCA and EDXA. These studies suggest that non-destructive chemical composition evaluation by EDXA and ESCA may also be applicable to CaP coatings.
Investigation of non-covalent ligand binding to the intact streptavidin tetramer by electrospray ionization mass spectrometry

The relative non-covalent binding behavior of two small molecule ligands to the tetrameric protein streptavidin was investigated by electrospray ionization mass spectrometry (ESI-MS). An extended m/z range quadrupole mass spectrometer was employed to observe the intact multimeric form of the protein and to probe the relative stabilities of the tetrameric protein- ligand complexes in the gas phase. Various protein:ligand molar ratio concentrations and incubation times were studied for the ligands biotin (Kd ≈ 10−15 M) and iminobiotin (Kd ≈ 10−7 M), in combination with the adjustment of variables in the ESI atmosphere-vacuum interface region. Positive-ion ESI-MS of a 1:7 molar ratio streptvidin–biotin sample produced peaks corresponding to the intact tetrameric complex (16+ to 14+ charge states) with four ligands binding to the active from of the protein. Only the expected specific non-covalent complexes of four ligand molecules binding to the protein tetramer were detected, consistent with known solution behavior and without the appearance of any random aggregation. However, under identical interface conditions, complete iminobiotin binding to the protein was not observed, even when higher ligand concentrations, longer complexation times and gentler interface conditions were employed. The thermally induced dissociation (TID) of the non-covalent complexes was studied by applying more severe conditions in the ESI interface region. In addition, observation of an intact streptavidin–biotinylated oligonucleotide non-covalent complex (17– to 14– tetrameric charge states) by negative-ion ESI-MS at m/z 4500–5000 is presented. The results show that the complexes observed in the mass spectrometer are representative of those that exist in solution, under the ESI conditions employed, and that the ability to observe such complexes is at least qualitatively related to stability in solution.
Symbolic Dynamics for IFS Attractors

It has recently been shown that a modified iterated function system (IFS) is capable of generating closed orbits which undergo bifurcation and transition to a chaotic regime as control parameters are varied.1,2 Here we show that driving such an IFS by a partition of itself creates maps which can be characterized by a symbolic dynamics. Forbidden words are determined for this dynamics under various parameter values, and the implications of this mapping are discussed.
Historical perspective of laser beam shaping

An overview of the history and current practices of laser beam shaping is presented. When diffraction effects are not important, geometrical methods for laser beam shaping (ray tracing, conservation of energy within a bundle of rays, and the constant optical path length condition) can be used to determine system configurations, including aspheric elements and spherical-surface GRIN lenses, which are required to transform an input laser beam profile into a more useful form of illumination. This paper also summarizes applications of these techniques to the optical design of a two-plano-aspheric lens system for shaping a rotationally symmetric Gaussian beam, a two-mirror system with no central obscuration for shaping an elliptical Gaussian input beam, and a three-element spherical surface GRIN system for shaping a rotationally symmetric Gaussian beam.
Creating auxotrophic mutants in Methylophilus methylotrophus AS1 by combining electroporation and chemical mutagenesis

Stable auxotrophic mutants of the methylotroph Methylophilus methylotrophus AS1 were obtained by a novel mutagenesis technique in which electroporation is used to transport the chemical mutagen N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) across the cell membrane. By combining chemical mutagenesis with electroporation and screening single colonies for auxotrophy in 36 different amino acids and growth factors, 3 auxotrophs per 156 colonies screened were obtained, whereas no auxotrophs were found with chemical mutagenesis alone. MNNG mutagen toxicity was also increased in the methylotroph with this novel mutagenesis technique (death rate 96% compared to 79%). This technique did not increase the mutation rate for strain Escherichia coli BK6 which responds well to simple exposure to the mutagen.
Economic Recession and the Fiscal Conditions of City Governments

It is a commonly accepted, but rarely tested, hypothesis that economic recession is a major contributor to urban fiscal stress. Most of the evidence for the association is based on aggregate state-...
Robust Simulation-Based Estimation of ARMA Models

This article proposes a new approach to the robust estimation of a mixed autoregressive and moving average (ARMA) model. It is based on the indirect inference method that originally was proposed for models with an intractable likelihood function. The estimation algorithm proposed is based on an auxiliary autoregressive representation whose parameters are first estimated on the observed time series and then on data simulated from the ARMA model. To simulate data the parameters of the ARMA model have to be set. By varying these we can minimize a distance between the simulation-based and the observation-based auxiliary estimate. The argument of the minimum yields then an estimator for the parameterization of the ARMA model. This simulation-based estimation procedure inherits the properties of the auxiliary model estimator. For instance, robustness is achieved with GM estimators. An essential feature of the introduced estimator, compared to existing robust estimators for ARMA models, is its theoretical tracta...
Tunneling spectroscopy of quantum point contacts.

A tunneling current flowing through a thin sidewall of quantum point contacts is calculated using a mode-matching technique. When the width of the construction is varied, successive peaks in the tunneling probability, which are synchronized with the quantized steps in the point-contact current, are observed due to the one-dimensional density of states in the constriction sweeping through the Fermi level. The modulation structure depends on the side-barrier potential. A resonant structure due to multiple reflections between sharp edges at the end of the point contact is superposed on the modulation if the point contact is sufficiently long compared with the wavelength. We find that a sharp peak occurs in the tunneling probability when the Fermi level coincides with a quasi-bound-state level in the constriction.
An agent-based simulation model of human-robot team performance in military environments

Prior to deploying human-robot teams on military missions, system designers need to understand how design decisions affect team performance. This paper describes a multiagent simulation model that captures both team coordination and human-robot interaction. The purpose of the model is to evaluate proposed team designs in uncertain Military Operations in Urban Terrain MOUT scenarios and determine which design factors are most critical to team performance. The simulation model is intended to be a tool in the systems engineering iterations of proposing designs, testing them, and then evaluating them during the conceptual design phase. To illustrate the model's usefulness for this purpose, a fractional factorial design of experiments is conducted to evaluate team design factors and the two-factor interaction between controllable factors and noise factors that described the environment and robot reliability. The experimental results suggest that 1 larger teams have more robust performance over the noise factors, 2 robot reliability is critical to the formation of human-robot teams, and 3 high centralization of decision-making authority created communication bottlenecks at the commander in large teams. This work contributes to the agent-based modeling of teams, and to understanding how the U.S. Army can attain its goal of greater utilization of robots in future military operations. ©2012 Wiley Periodicals, Inc. Syst Eng 15
Uncertainty and Candidate Personality Traits

Due to the high level of uncertainty in the electorate about candidate issue positions, many scholars believe that voters instead use simpler cues such as personality traits to evaluate candidates. However, information about candidate personality traits is also subject to uncertainty. Using a new direct survey measure of uncertainty included in the 1995 and 1996 National Election Studies, we examine the effect of trait opinions on candidate evaluations and test the effect that uncertainty about those opinions has on the use of traits in an evaluation. We find that uncertainty about a candidate's personality traits reduces both the use of opinions about that candidate's traits in evaluations of that candidate and the overall evaluations of that candidate
A direct finite element analysis method for particle mechanics: The three-body problem

Abstract A finite element analysis technique for the solution of problems in particle mechanics is described. In this approach, physical laws in the form of linear equations are used in the calculations to arrive at numerical results giving the temporal development of a system of particles. Since the formulation is not in terms of differential equations the associated problem of their solution is not encountered. The simple and damped harmonic oscillator and the classical three-body problem are discussed. The results of the computer calculations for special cases are compared with known analytical solutions. The introduction of error and its correction in the numerical calculations is discussed.
c-fos induction in sensory pathways of rats exploring a novel complex environment: shifts of active thalamic reticular sectors by predominant sensory cues.

Abstract In normal rats exploring a novel, complex environment, in comparison to control non-exploring rats, there is induction of the FOS protein, a marker of neuronal activity, in all layers of the striate visual cortex (particularly in the granular and supragranular layers), in the stratum griseum superficiale of the superior colliculus, and in the dorsal lateral geniculate nucleus, as well as in all layers of the whiskers barrel field in the somatosensory cortex. A surprising finding was a selective activation of the visual sector of the thalamic reticular nucleus, in dorsocaudal parts of the nucleus. To the contrary, in visually deprived rats exploring a novel environment which would depend critically on whiskers tactile clues for exploration there was instead a selective activation of the somatic sector in central parts of the thalamic reticular nucleus, in conjunction with activation of cortical whiskers barrel field. From these results it is concluded: (1) Different sensory sectors of the rat thalamic reticular nucleus are activated depending on prevalent sensory channels used in recognition of the environment, suggesting a role of thalamic reticular nucleus in optimizing thalamocortical transmission of essential external cues to guide adequate behaviour. (2) In the awake state, the granular and supragranular layers of the visual and somatosensory cortices are more active when attention is paid to sensory stimuli that are essential for recognition of the environment. (3) The selective induction of c-fos in the visual and somatosensory cortices, and in the stratum griseum superficiale of superior colliculus of rats exploring a novel, complex environment might be related to plastic changes that have been demonstrated in these centres in rats raised in complex environments. These plastic changes are likely to be the result of target late-response genes activated by c-fos.
Optimization of the Kinematics of a Flapping Wing MAV in Hover for Enhanced Performance

exible apping wing micro air vehicle (MAV) in hover are optimized for enhanced performance using surrogate based approximation of the unsteady aerodynamic loads. The surrogates are generated using kriging interpolation of the time averaged thrust generated and power consumed by the wings. The tting data is obtained using a nonlinear approximate aeroelastic model that combines a nonlinear nite element based structural dynamic model with an approximate unsteady aerodynamic model. The parameter space for the rigid wings consists of seven kinematic parameters. For the exible
Absent-decreased perfusion in the cerebral SPECT study using I-123 HIPDM.

A 57-YEAR-OLD man was brought to the emergency room because of the sudden onset of left hemiparesis and intermittent aphasia. The patient had symptoms of right hand numbness, tingling, and bilateral amaurosis fugax for about 1 month prior to the onset. Neurological examinations revealed decreased sensation on the left side of the face, decreased sensation of light touch and pin-prick, and decreased vibratory sense in the distal aspect of the left upper and lower extremities. He had double simultaneous extinction of the left side of his body. Blood pressure was 120/70 mm Hg with pulse rate 74/min. Laboratory findings including completed blood cell count (CBC) and liver function tests were normal. Computed tomography (CT) of the head, performed on the first day of illness, was negative. A cerebral flow study using 1-123 HIPDM showed absentdecreased flow in th right parietal region (Fig I). A four vessel carotid angiogram confirmed complete occlusion of the right internal carotid artery at its origin and infarction of the posterior right frontal lobe and parietal lobe (Fig 2). He was given heparin for seven days with regression of symtoms of weakness, and then placed on aspirin and Persantine. The recent development of I-123 amphetamine analogs, N-isopropyl-p-I123-iodoametamine (I123 IMP) 1'2 and 1-123 N, N, N, 'tr imethyl-N'-[2-hydroxy-3-methyl-5-iodobenzyl]1, 3-propanediamine (1-123 HIPDM), 2'3 has created a new wave of interest in radionuclide cerebral studies. These agents are lipid soluable and enter the brain across the normal BBB, localizing in the brain tissue depending on regional cerebral blood flow? These agents with the availability of SPECT facilities in a nuclear medicine service of the community hospital allows the performance of cerebral flow SPECT images, proving functional/physiological information which is not available by any other noninvasive technique. Tc-99m HM-PAO 4,s is a cerebral flow agent that give information similar to that obtained with 1-123 IMP or 1-123 HIPDM and may also be widely used in the future in this country. Probable causes of absent or decreased cerebral flow are as follows:
Cognitive Diversity in the Global Academy: Why the Voices of Persons with Cognitive Disabilities are Vital to Intellectual Diversity

In asking scholars to reflect on the “structures and practices of academic knowledge that render alternative knowledge traditions irrelevant and invisible,” as well as on the ways these must change for the academy to cease “functioning as an instrument of westernization rather than as an authentically global and diverse intellectual commons,” the editor of this special issue of the Journal of Academic Ethics is envisaging a world much needed and much resisted. A great deal of the conversation about diversity in higher education emphasizes, rightly, the need for an international and ethnically diverse population of scholars and students. Less attention is paid to the value of cognitive diversity—the diversity of cognition generated by cognitive disabilities. As one aspect of intellectual diversity, cognitive diversity promises novel ways of thinking and new understandings of what knowledge is, who makes it, and how it is made. The unique value of cognitive diversity is its insistence on a radical shift in our conception of who can know and who can produce knowledge. Insisting on the inclusion, as scholars, of persons with minds labelled disabled, an epistemology of disability pushes us to reform the much criticized but still dominant notion of the expert and scholar as able-bodied and hyper-rational.