cssi/SciSciGPT-SciSciNet huggingface dataset:
Birefringence control for ion-exchanged channel waveguides at 1.55-μm wavelength

We show at 1.55 micrometer wavelength that the waveguide birefringence of ion-exchanged channel waveguides in glass can be broadly tuned by a potassium and silver double-ion- exchange. Two different potassium and silver double-ion- exchange processes are used to make surface waveguides with negligible waveguide birefringence. This is of crucial importance in making devices for dense wavelength division multiplexing (DWDM) systems. The dependence of the waveguide birefringence on the channel width is also reported.
Characterization and Single Molecule Conformational Studies of Soluble Alpha-Synuclein Oligomers

Alpha-Synuclein (αS) is a natively unstructured protein central to the pathology of Parkinson's disease. A growing body of evidence suggests that soluble oligomeric αS species are responsible for cell death which perpetuates Parkinson's. A variety of protocols have been described which populate oligomers in vitro for biophysical characterization, yet it remains unclear if these disparate protocols yield similar species and if these species are relevant to disease states. Furthermore, detailed structural analysis of these oligomers, which could be exceptionally useful towards elucidating mechanism of toxicity and avenues for disease treatment, remains difficult given their low abundance and apparent heterogeneity. In order to compare their bulk structural characteristics, we have prepared αS oligomers from a variety of protocols and characterized them using anti-oligomer antibody A11, cytotoxicity assays and colocalization studies with SH-SY5Y neuroblastoma cells, and ThT fluorescence to probe their ability to seed amyloid fibrillation. Our studies have identified a subset of oligomers which are on the order of 50 αS monomers in size, are A11-reactive, linking them to disease states in vivo, and are toxic to and readily taken up by cells in culture. We use single molecule Forster resonance energy transfer to measure the conformational states of individual αS monomers incorporated into oligomers. We have found in multiple regions of αS the protein apparently adopts a highly heterogeneous ensemble of conformations within oligomers, which emphasizes the suitability of single molecule techniques for their study. Through understanding the conformational states of αS before and after aggregation to toxic oligomeric species, we will provide insight into the mechanism of oligomer formation and toxicity.
Adenomatoid odontogenic tumor: Clinicopathologic and ultrastructural concepts

Two cases of adenomatoid odontogenic tumor have been presented, along with a review of the literature. One tumor had a rather typical presentation, occurring in a 12-year-old in association with an impacted canine tooth. Subsequent electron microscopic evaluation of this case provided corroboration of other recently published findings. In this case there was a striking accumulation of what could have been secretory granules at the pole of the cell nearest a "duct-like" space. This cell had ultrastructural characteristics in common with a preameloblast. The second case occurred in a more unusual situation, the patient being a 32-year-old man, with the AOT developing in the mandible between the roots of the canine and first premolar. Both patients were treated successfully by simple enucleation of the lesion.
De-Centering Religion as Queer Pedagogical Practice

Inasmuch as the value of teaching rests in its liberating consciousness-raising possibilities, teaching theological ethics ought to aim toward and build upon justice-oriented practice. My efforts at justice-making in the classroom, especially around the subjects of race, gender, and sexuality, assume the necessity of diverse individual’s and communities’ real experiences of moral agency, thereby de-centering religion as the norm for doing ethics. Thus, religion, and specifically Christianity, becomes a source within the scholarly endeavor. In this paper, I delineate my own experiences and practices of teaching race, gender and sexuality in two contexts, offering explanations of the ways those practices de-center religious perspectives and privilege experience as a source.
Experimental Evaluation of Foil Bearing Performance: Steady-State and Dynamic Results

An experimental facility dedicated to measuring both the steady-state and dynamic properties of foil bearings, under a variety of operating conditions, has been designed and commissioned. The bearing under test is placed at the midspan of a horizontal, simply-supported, stepped shaft which rotates at up to 60 krpm. Static and dynamic loads of up to 3500 N and 450 N (respectively) can be applied by means of a pneumatic cylinder and two electrodynamic shakers. This paper outlines the test procedures and data analysis methods pertaining to the operation of the high-speed, oil-free bearing test rig, and presents steady-state and dynamic results for a first-generation foil bearing. The test bearing, which was fabricated in-house, is 0.07 m diameter and has an aspect ratio of 1; bearing manufacturing details are provided.© 2009 ASME
Energy loss dependence of X-rays emitted by titanium ions channeled in a thin gold single crystal

Abstract X-rays generated by fully stripped titanium ions channeled along the 〈100〉 axis of a thin gold single crystal have been measured in coincidence with charge-changed ions as a function of ion energy loss. X-rays from the process of radiative electron capture are used to derive mean target electron densities for three values of mean energy loss. These densities are compared with densities calculated from a free-electron gas model for stopping. The results are used in a model calculation for Lyman series X-ray emission yields which includes effects of strong competition from secondary electron impact excitation and ionization of excited-state hydrogenic ions formed by electron capture in the crystal.
Removal of Stratospheric O3 by Radicals: In Situ Measurements of OH, HO2, NO, NO2, ClO, and BrO

Simultaneous in situ measurements of the concentrations of OH, HO_2, ClO, BrO, NO, and NO_2 demonstrate the predominance of odd-hydrogen and halogen free-radical catalysis in determining the rate of removal of ozone in the lower stratosphere during May 1993. A single catalytic cycle, in which the rate-limiting step is the reaction of HO_2 with ozone, accounted for nearly one-half of the total O_3 removal in this region of the atmosphere. Halogen-radical chemistry was responsible for approximately one-third of the photochemical removal of O_3; reactions involving BrO account for one-half of this loss. Catalytic destruction by NO_2, which for two decades was considered to be the predominant loss process, accounted for less than 20 percent of the O_3 removal. The measurements demonstrate quantitatively the coupling that exists between the radical families. The concentrations of HO_2 and ClO are inversely correlated with those of NO and NO_2. The direct determination of the relative importance of the catalytic loss processes, combined with a demonstration of the reactions linking the hydrogen, halogen, and nitrogen radical concentrations, shows that in the air sampled the rate of O_3 removal was inversely correlated with total NO_x, loading.
Sedimentation in bottomland hardwoods downstream of an east Texas dam

Dams and reservoirs are often efficient sediment traps, and conventional wisdom holds that fluvial sediment supplies are reduced well downstream. However, there are reasons to question the extent to which fluvial and alluvial sediment supplies are reduced more than a few kilometers downstream of dams. Sedimentation in bottomlands of Loco Bayou, east Texas, was investigated at a site less than 16 km downstream of Loco Dam and Lake Nacogdoches, which controls 86% of the 265-km2 drainage area. Turbidity levels are generally as high or higher than those on Loco Bayou upstream of the lake. Sedimentation rates on the lower floodplain since the dam was completed are 11 mm year–1 or more. This rate is high enough to suggest that the dam has no effect on sediment supplies 16 km downstream. The spatial pattern of sedimentation and the vegetation distribution suggest that the elevation and frequency of flooding, not fluvial sediment availability, are the critical factors in determining sediment supplies to these floodplains.
Polarized light field microscopy: an analytical method using a microlens array to simultaneously capture both conoscopic and orthoscopic views of birefringent objects

For the comprehensive analysis of anisotropic materials, a new approach, called 'polarized light field microscopy' is introduced. It uses an LC-PolScope to which a microlens array was added at the image plane of the objective lens. The system is patterned after the 'light field microscope' that achieves both lateral and axial resolution in thick specimens in a single camera exposure. In polarized light field microscopy, the microlens array generates a hybrid image consisting of an array of small conoscopic images, each sampling a different object area. Analysis of the conoscopic images reveals the birefringence of each object area as a function of the propagation direction of transmitted light rays. The principles and utility of the instrument that we are calling 'light field LC-PolScope' are demonstrated with images of a thin, polycrystalline calcite film, revealing the azimuth and inclination angle of the optic axis for many crystals simultaneously, including crystals with diameters as small as 2 microm. Compared to traditional conoscopy and related methods, the vastly improved throughput and quantitative analysis afforded by the light field LC-PolScope make it the instrument of choice for measuring 3D birefringence parameters of complex structures.
MICE: a mouse imaging collaboration environment

With the ever-increasing complexity of science and engineering, many important research problems are being addressed by collaborative, multidisciplinary teams. We present a web-based collaborative environment for small animal imaging research, called the Mouse Imaging Collaboration Environment (MICE). MICE provides an effective and user-friendly tool for managing and sharing of the terabytes of high-resolution and high-dimension image data generated at small animal imaging core facilities. We describe the design of MICE and our experience in the implementation and deployment of a beta-version baseline-MICE. The baseline-MICE provides an integrated solution from image data acquisition to end-user access and long-term data storage at our UH/Case Small Animal Imaging Resource Center. As image data is acquired from scanners, it is pushed to the MICE server which automatically stores it in a directory structure according to its DICOM metadata. The directory structure reflects imaging modality, principle investigators, animal models, scanning dates and study details. Registered end-users access this imaging data through an authenticated web-interface. Thumbnail images are created by custom scripts running on the MICE server while data down-loading is achieved through standard web-browser ftp. MICE provides a security infrastructure that manages user roles, their access privileges such as read/write, and the right to modify the access privileges. Additional data security measures include a two server paradigm with the Web access server residing outside a network firewall to provide access through the Internet, and the imaging data server - a large RAID storage system supporting flexible backup policies - residing behind the protected firewall with a dedicated link to the Web access server. Direct network link to the RAID storage system outside the firewall other than this dedicated link is not permitted. Establishing the initial image directory structure and letting the project leader manage data access through a web-interface represent Phase I implementation. In Phase II, features for uploading image analysis scripts and results back to the MICE server will be implemented, as well as mechanisms facilitating asynchronous and synchronous discussion, annotation, and analysis. Most of MICE features are being implemented in the Plone5 object-oriented database environment which greatly shortens developmental time and effort by the reuse of a variety of Plone's open-source modules for Content Management Systems.7, 8 The open-source modules are well suited as an implementation basis of MICE and provide data integration as a built-in primitive.
The potential for interpreting total and multiyear ice concentrations in SSM/I 85.5 GHz imagery

Abstract The 85.5 GHz vertically and horizontally polarized channels of the Special Sensor Microwave Imagers (SSM/I) aboard the Defense Meteorological Satellite Program (DMSP) spacecraft offer the potential to map sea ice with a spatial resolution of 12.5 km, a factor of two improvement over the popular National Aeronautics and Space Administration (NASA) Team algorithm, but with the limitation of increased atmospheric influence on the sea ice signal. Application of an algorithm for estimating total ice concentration from 85.5 GHz data, which exploits the large polarization for open water versus the small polarization for most ice types, reveals agreement with the NASA Team algorithm typically within a standard deviation of ± 3% for nearly cloud free winter conditions. The uncertainty increases to a standard deviation of ± 6% for cloudy winter conditions. In winter, volume scattering from multiyear ice has a noticeable impact on the 85.5 GHz brightness temperatures. By employing a polarization corrected temperature variable previously defined to isolate precipitation in mid-latitude DMSP imagery, it is possible to exploit the large differences in 85.5 GHz emissivity between first year and multiyear ice to interpret an 85.5 GHz image in terms of both total ice and multiyear ice concentration. Preliminary results, for nearly cloud free winter conditions, reveal agreement between these interpretations and the NASA Team algorithm to within a standard deviation of ± 6%, with slightly better agreement at low multiyear ice concentration.
Infrared spectral examination of air monitoring badges

A technique has been devised to use infrared spectroscopy for examination of organic vapor personal air monitoring badges. These badges (passive dosimeters) are traditionally examined by liquid desorption followed by gas chromatography of the resulting solution of air contaminants. The GC method assumes prior knowledge of the presence of specific compounds, and, if additional peaks appear in the chromatogram they are often ignored. Conversely, if the analysis is done by infrared spectroscopy, much more information is obtained both to confirm the expected contaminants and to identify any unsuspected ones that appear in the spectrum. The infrared spectral procedure involves the usual carbon disulfide desorption, followed by withdrawal of a portion of the CS2 solution with a syringe, and either evaporation into a 20-meter gas infrared cell, or examination in a 0.5 mm liquid cell. The background CS2 spectrum does not seriously interfere with the identification and quantitative measurement of most organic comp...
Synthesis and properties of cyclic peptides containing the activation site of plasminogen.

The activation of plasminogen results from proteolytic cleavage of the Arg560-Val561 bond by plasminogen activators (Sottrup-Jensen et al. PNAS (1975) 72, 2577). This region of the zymogen occurs in a small disulfide loop that must restrict the conformation around this bond. The nonapeptide sequence NH2-Cys-Pro-Gly-Arg-Val-Val-Gly-Gly-Cys-NH2 of plasminogen containing the activator sensitive arginyl valine bond was synthesized by carbodiimide coupling of Boc-Cys-Pro-Gly-OH(S-4-methylbenzyl) to NH2-Arg(NO2)-Val-Val-Gly-Gly-Cys-NH2(S-4-methylbenz(S-4-methylbenzyl), followed by HF treatment and K3Fe(CN)6 oxidation to form a disulfide bond. Purified peptide was not a substrate for urokinase (UK) or plasminogen activator (PA) but possessed a slightly inhibitory activity towards PA. Addition of a lysine to the N-terminus of the nonapeptide yielded a decapeptide sequence of plasminogen that was a better substrate for UK but not for PA. The decapeptide inhibits PA slightly but not UK. These results suggest that active site geometry for PA must be more restrictive than that of UK and that other regions may be involved in the productive interactions with the activators inducing a better fit of the cyclic peptide loop.
New NSF directorate

A few years ago the National Science Foundation expanded its basic research programs to include areas not normally thought of as being in the realm of science. These included behavioral and social sciences and extended to high school education and international affairs. The result was an organization of six directorates. Now the NSF will be undergoing a major change, which will include the replacement of the directorate for engineering and applied sciences by a new directorate for the support of engineering alone. According to the current acting director of NSF, Donald Langenberg, and the director-designate, John B. Slaughter, the basic research programs of the foundation will not be cut or diminished, but nonetheless the NSF will be significantly reorganized, starting in the first part of 1981. Applied research is to be distributed among all of the directorates, which carries the implication that the foundation will take a more applied, rather than basic, approach in the future.
Using computer technology for health education.

The Internet has been growing tremendously since 1988 becoming extremely useful for health education specialists. Some services available on the Internet are: electronic mail (E-mail) mail lists/discussion groups (listservs) electronic bulletin boards (BBS) newsgroups (Usenet) and internet relay chat (IRC). The World Wide Web (WWW) makes it possible to exchange text pictures and sound. A computer modem communications software phone line and Internet Service Provider (ISP) are needed to connect to the Internet. Mailing lists or listservs have also been developed to send messages to a collection of E-mail addresses for information exchange and discussion. In health education and promotion the following mailing lists are important: HPRIN (Health Promotion Research Internet Network) operated by the Karolinska Institute in Sweden; HEDIR (International Electronic Mail Directory for Health Educators) operated by Southern Illinois University at Carbondale US; HLTHPROM a health promotion discussion list operated by the University of Wisconsin-Madison US. The North American Regional Office (NARO) of the International Union for Health Promotion and Education also established a mailing list for its members in cooperation with New York University to facilitate communication about international health education (conference announcements jobs internships resources news funding sources and discussion). The WWW provides access to enormous amounts of information and pictures using a browser program such as Netscape. Hypertext provides a link to other data or to a service. Some of the services connected to the Web are anonymous FTP (file copying) gopher (finding data through menus) and telnet (connecting to another computer). Users can create their own information on web pages by means of hypertext markup language or HTML to create a web page. A unique address called URL (Uniform Resource Locator) is needed for locating a resource on the Web. At New York University computer training has been part of health education specialist training.
Complications after 147 consecutive vertebral column resections for severe pediatric spinal deformity: A multicenter analysis

Study Design. Retrospective multicenter review. Objective. Determine the definition, indications, results, and outcomes, focusing on complications of vertebral column resection (VCR) for severe pediatric spinal deformity. Summary of Background Data. The strict definition of the VCR procedure, indications, results, outcomes, and the numerous, potentially serious complications are unknown or controversial, and a large multicenter review has never been performed. Methods. A total of 147 patients treated by 7 pediatric spinal deformity surgeons were reviewed—seventy-four females and 73 males, with an average age of 13.7 years, an average of 1.6 (range, 1–5) vertebrae resected, and an average follow-up of 17 months (range, 0.5–64 mo). The strict definition of VCR used was a “3-column circumferential vertebral osteotomy creating a segmental defect with sufficient instability to require provisional instrumentation.” Results. Indications for a VCR were divided into 5 diagnostic categories: kyphoscoliosis (n = 52), severe scoliosis (n = 37), congenital deformity (n = 28), global kyphosis (n = 17), and angular kyphosis (n = 13). Eighty-four primary and 63 revision patients with 174 operative procedures, 127 posterior-only (17 staged), and 20 patients combined anterior-posterior (10 staged) were reviewed. Average preoperative upright, flexibility, and postoperative Cobb measures (% correction or average kyphosis decrease) were kyphoscoliosis: 91°, 65°, 44° (51% coronal), 104°, 81°, and 47° (decrease, 57° sagittal); severe scoliosis: 104°, 78°, and 33° (67%); congenital deformity: 47°, 38°, 22° (46% coronal), 56°, 48°, and 32° (decrease, 24° sagittal); global kyphosis: 101°, 79°, and 47° (decrease, 54°); and angular kyphosis: 88°, 90°, and 38° (decrease, 50°), respectively. Operative time averaged 545 minutes (range, 204–1355 min) and estimated blood loss averaged 1610 mL (range, 50–8244 mL) for an average 65% blood volume loss (range, 6%–316%). Eighty-six patients (59%) developed a complication, 39 patients (27%) having an intraoperative neurological event (spinal cord monitoring change or failed wake-up test); however, no patient had complete permanent paraplegia. Conclusion. A total of 147 consecutive pediatric VCRs performed by 7 surgeons demonstrated excellent radiographical correction. However, these complex reconstructions were associated with a 59% complication rate, thus emphasizing the challenging nature of these patients and procedures.
Nonlinear acoustic echo cancellation using feedback

Acoustic echo cancellation (AEC) is a well studied problem. One of the main assumptions in existing AEC techniques is that the echo path is linear. In today's equipment, this assumption does always hold. The increasing focus on the look and feel of commercial devices and consequently the decreasing size of their loudspeakers are the major contributors to making the echo path nonlinear. This emphasizes the need for a nonlinear echo canceler to maintain the required echo return loss enhancement (ERLE). Many algorithms have been proposed to solve this problem, but they are prohibitive because of their high computational complexity. This paper proposes a hardware modification to significantly reduce the nonlinear echo. Results show that up to 6 dB of improvement in ERLE in a real device are possible.
Increased ovarian cancer risk associated with menopausal estrogen therapy is reduced by adding a progestin

BACKGROUND. It has become increasingly clear that use of menopausal hormone therapy (HT) is associated with an increased risk of ovarian cancer; however, the effects by type of formulation and duration of use are less clear. A systematic review of the HT and ovarian cancer literature was conducted to identify population-based case-control studies, cohort studies, and randomized trials that examined effects by formulation of HT (estrogen-alone [ET] and estrogen plus progestin [EPT]) and duration of use. METHODS. Pub-Med (www.pubmed.gov) was used to identify relevant publications through December 2007; 14 studies were identified. The authors abstracted relative risks (RRs) and 95% confidence intervals (CIs) in relation to duration of HT use (ET and EPT separately). The authors used the risk estimates per year of HT use if these were provided; otherwise, they calculated a duration-response for a log-linear model of the duration of HT use against risk. RESULTS. Ovarian cancer risk was increased among ET users (RR per 5 years of use, RR5 = 1.22; 95% CI, 1.18-1.27; P < .0001), and a lower but still statistically significant increased risk was seen with EPT use (RR5 = 1.10; 95% CI, 1.04-1.16; P = .001). The increased risk in ET users was statistically significantly higher than the increased risk in EPT users (P = .004). CONCLUSIONS. ET use increases risk of ovarian cancer in a duration-dependent manner, and it appears that the addition of progestins blocks this effect, at least to some extent. Whether the effect of estrogens would be completely blocked if progestins were given every day is unclear. Cancer 2009. © 2009 American Cancer Society.
A mathematical model for evaluation of forces in lower extremeties of the musculo-skeletal system

Abstract This study deals with the development of a mathematical model for the musculo-skeletal system capable of evaluating muscle forces and joint reactions for different static postures. The problem is formulated as a linear program and solved by means of a simplex algorithm. Different criteria are used for evaluation of the muscle forces necessary to maintain the human body equilibrium in standing, leaning and stooping. The analytical results show good correlation with electromyographic signals from surface electrodes placed on the superficial muscles. The feasibility of this approach for quantitative analysis of musculoskeletal forces is demonstrated. The technique represents the first attempt at a mathematical model of the musculo-skeletal system and can be readily extended for complete simulation of the force system controlling human body actions and motions. It provides a valuable tool for diagnosis of muscle malfunctions, changes in musculoskeletal forces resulting from injury and synthesis of assistive devices for rehabilitation.
GaAs CCD readout for engineered bandgap detectors

GaAs and related heterostructure charge-coupled devices (CCDs) for detector array readout multiplexer applications are described. Features of resistive-gate CCDs are compared with capacitive-gate CCDs for this application. Design examples of GaAs CCD readouts for linear and two-dimensional detector arrays with different detection methods and signal coupling schemes are described. Recent progress in two-dimensional electron gas (2DEG) Al(0.3)Ga(0.7)As/GaAs resistive-gate CCDs is also presented. The 2DEG resistive-gate CCD conventional buried-channel GaAs CCD.
Time's up, timed out: reflections on social time and legal pluralism

This essay connects two longstanding anthropological themes by reconsidering Durkheim's distinction between social time and personal time through the lens of legal pluralism; I also turn the temporal lens the other way, to reflect on legal pluralism. Drawing on the work of the von Benda-Beckmanns, I begin by suggesting that we might look for illuminating connections between social time and legal pluralism wherever people make urgent demands of law, and wherever states turn to law as a means of social engineering. That possibility informs my essay and choice of examples, all from the United States. First, I review two major pieces of social legislation that were explicit in their social engineering goals. Next, I consider the temporalities inscribed in the eligibility requirements for social programs set up under the broad terms of those acts. In the conclusion, I return to the question of how social time and legal pluralism might be mutually informing in ways that shed fresh light on both themes – blurrin...
Aortic Atheroma Burden and Cognitive Dysfunction After Coronary Artery Bypass Graft Surgery

Abstract Background Neurocognitive dysfunction (NCD) after coronary artery bypass graft (CABG) surgery is a common problem. Atherosclerotic disease of the aorta is a known risk factor for stroke after cardiac surgery, but its relationship to NCD is unclear. This study investigates the relationship between aortic atherosclerotic disease and NCD after CABG. Patients and Methods Patients undergoing primary elective CABG were enrolled in an ongoing investigation of NCD after CABG. Intraoperative transesophageal echocardiography (TEE) of the thoracic aorta was performed and analyzed off-line to quantify atheroma burden. Neurocognitive evaluation was performed, both preoperatively and at 6 weeks after surgery. Multivariable linear regression (controlling for age, years of education, and base line cognitive index) was used to determine the relationship between NCD and atheroma burden in the ascending, arch, and descending aorta. Results One hundred sixty-two patients who had a complete neurocognitive evaluation and adequate TEE images were studied. No significant relationship was found between NCD and atheroma burden in the ascending ( p = 0.22), arch ( p = 0.89) or descending aorta ( p = 0.64). Conclusions Although the etiology of NCD is likely multifactorial, our results suggest that aortic atherosclerosis may not be the primary factor in the pathogenesis of post-CABG cognitive changes.
Amphipod performance responses to decaying leaf litter of Phragmites australis and Typha angustifolia from a Lake Erie coastal marsh

ABSTRACT We compared growth and survival performance of the detritivorous amphipod Hyalella azteca fed lab-conditioned leaves of either Typha angustifolia (narrow-leaf cattail), Phragmites australis (common reed) sprayed with the herbicide Glypro®, and unsprayed Phragmites in microcosms. Leaves were from plants varying in time of senescence. Herbicide application advanced plant senescence and death by ~3 months, whereas the other two leaf types senesced naturally. Amphipods grew, on average, ~100 µg d−1, and amphipod growth was positively related to fungal biomass on leaves, suggesting that fungi were a key nutritive source. Average fungal biomass was significantly greater on herbicide-treated, early sensecent Phragmites (317 ± 43 µg ergosterol g−1 dry wt.; mean ± 1 SE) and Typha (226 ± 39 µg ergosterol g−1 dry wt.) than on naturally senescent Phragmites (114 ± 21 µg ergosterol g−1 dry wt.). Leaf toughness, an indicator of unpalatability, was greatest on naturally senescent Phragmites leaves. Even so, amp...
Multi-Color Quantum Dot Tracking Using a High-Speed Hyperspectral Line-Scanning Microscope

Many cellular signaling processes are initiated by dimerization or oligomerization of membrane proteins. However, since the spatial scale of these interactions is below the diffraction limit of the light microscope, the dynamics of these interactions have been difficult to study on living cells. We have developed a novel high-speed hyperspectral microscope (HSM) to perform single particle tracking of up to 8 spectrally distinct species of quantum dots (QDs) at 27 frames per second. The distinct emission spectra of the QDs allows localization with ∼10 nm precision even when the probes are clustered at spatial scales below the diffraction limit. The capabilities of the HSM are demonstrated here by application of multi-color single particle tracking to observe membrane protein behavior, including: 1) dynamic formation and dissociation of Epidermal Growth Factor Receptor dimers; 2) resolving antigen induced aggregation of the high affinity IgE receptor, FceR1; 3) four color QD tracking while simultaneously visualizing GFP-actin; and 4) high-density tracking for fast diffusion mapping.
Assaults on police officers in American cities.

Hitherto, no research has looked for correlates of assaults by citizens on police officers in American cities. To explore this question assault rates by citizens on police officers (expressed per 1,000 policemen) were obtained for 1974 and 1975 for all large cities that fully report such data (n = 26).l The product-moment correlation between the rates for the two years was 0.94 (twotailed p < 0.001), indicating that these rates are highly reliable. The assault rates for 1975 were not significantly related to the number of police officers in the cities in 1975 (r = -0.22), the number of police officers per 100,000 population in 1970-1975 (r = -0.20), the population of the cities in 1970 (r = -0.20), the population density in 1970 (r = -0.28), the percentage of the population that was black in 1970 (r = 0.06), the percentage of the population below the poverty level in 1970 (r = 0.06), the degree of residential segregation in 1970 (r = 0.19), the crime index rate in 1975 (r = 0.14), the rate with which police officers were murdered in the period 1970-1975 (r = 0.13), the mean annual temperature (r = 0.09), the number of days per year below freezing (r = -0.35), and the elevation above sea level (r = -0.01 ) .* , This study failed to find any correlates of the assault rates on police officers. It may be that reporting practices for what constitutes an assault on a police officer vary widely from city to city, so that although the rates are reliable, they are not valid or comparable. It may also be that the crucial variables are related to the kinds of men recruited as ,policemen, their training, and departmental organization. Unfortunately no comparative data exist for such variables. REFERENCE
Ab initio genotype–phenotype association reveals intrinsic modularity in genetic networks

Microbial species express an astonishing diversity of phenotypic traits, behaviors, and metabolic capacities. However, our molecular understanding of these phenotypes is based almost entirely on studies in a handful of model organisms that together represent only a small fraction of this phenotypic diversity. Furthermore, many microbial species are not amenable to traditional laboratory analysis because of their exotic lifestyles and/or lack of suitable molecular genetic techniques. As an adjunct to experimental analysis, we have developed a computational information-theoretic framework that produces high-confidence gene–phenotype predictions using cross-species distributions of genes and phenotypes across 202 fully sequenced archaea and eubacteria. In addition to identifying the genetic basis of complex traits, our approach reveals the organization of these genes into generic preferentially co-inherited modules, many of which correspond directly to known enzymatic pathways, molecular complexes, signaling pathways, and molecular machines.
Depletion and Repopulation of Leydig Cells in the Testes of Aging Brown Norway Rats

The capacity of Brown Norway rat Leydig cells to produce testosterone has been shown to decrease with aging. Our objectives herein were to determine 1) whether ethane dimethanesulfonate (EDS) administration would eliminate the hypofunctional Leydig cells of the aged Brown Norway rat testis; 2) if so, whether a new generation of Leydig cells subsequently would appear; and 3) if so, whether the steroidogenic capacity of the new Leydig cells would be at the relatively low level of the cells they replaced or at the high level of young adult Leydig cells. Young (3-month-old) and aged (18-month-old) rats received an injection of EDS (8.5 mg/100 g BW). One, 5, and 10 weeks thereafter, the serum testosterone concentration and the capacity of the testes and of isolated Leydig cells to produce testosterone were determined. One week after EDS treatment, Leydig cells were not seen in the testes of young or aged rats, and the serum testosterone concentration and testicular testosterone production were reduced to undet...
Simulation of quantum transport in memory-switching double-barrier quantum-well diodes.

Recent experiments on GaAs/AlAs double-barrier diodes incorporating ${\mathit{n}}^{\mathrm{\ensuremath{-}}}$/${\mathit{n}}^{+}$/${\mathit{n}}^{\mathrm{\ensuremath{-}}}$ spacer layers have shown that they exhibit two conduction curves that remain distinct across zero bias. Such devices can be reversibly switched between the two conduction curves and retain memory of the curve last switched to, even after short-circuit conditions. In this paper, we model the memory-switching phenomenon using a quantum kinetic formulation based on the Wigner distribution function. To obtain accurate Wigner distribution functions, an improved four-point difference scheme with an upwind bias is used to model the drift term in the equation of motion. The calculations result in two equilibrium (zero-voltage) states in double-barrier diodes incorporating ${\mathit{n}}^{\mathrm{\ensuremath{-}}}$/${\mathit{n}}^{+}$/${\mathit{n}}^{\mathrm{\ensuremath{-}}}$ spacer layers. Associated with each equilibrium state is a distinct and stable conduction curve. This work is a step toward an understanding of the more complex aspects of the phenomenon, such as state switching when the device is driven far from equilibrium.
Analysis of Local Sales Taxation in Rural Areas: An Oklahoma Case Study

This study examines the impact of tax rates and tax rate differentials in a trade area on local sales tax revenues. Sales data for FY 1986 were analyzed for the 75 nonmetropolitan communities in Oklahoma with populations between 2,500 and 50,000. Multiple regression techniques were used to estimate local tax revenues as a function of tax rates, tax rate differential and local community economic and locational attributes. The results indicate that the tax rate differential was not significantly related to local revenue collection in the overall sample, but that the differential was significant for rural communities with relatively higher tax rates. Tax rate, income, service sector employment and a gravity factor were also significant influences on local sales tax revenues. These results imply that, because of the unique characteristics of rural retail markets and the dominance of rural trade centers, these rural trade center cities are able to raise local tax rates and effectively export tax burden to nonresidents without significantly affecting their retail sales when the tax differential is not a large one.
Transcranial Doppler in Reversible Migrainous Vasospasm Causing Cerebellar Infarction: Report of a Case:

A young woman with a history of classic migraine suffered a large cerebellar infarction . Comprehensive evaluation did not disclose any potential causes for the stroke and she had no other risk factors. Transcranial Doppler (TCD) was useful in identifying vasospasm of the vertebral arteries. Following treatment with propranolol, angiography and repeat TCD revealed resolution of the vasospastic disorder.TCD is a useful noninvasive tool in detecting vasospasm associated with ischemic lesions in certain patients with migraine.
Richard Swinburne, The Existence of God, and Exact Numerical Values

Richard Swinburne’s argument in The Existence of God discusses many probabilities, ultimately concluding that God probably exists. Swinburne gives exact values to almost none of these probabilities. I attempted to assign values to the probabilities that met that weak condition that they could be correct. In this paper, I first present a brief outline of Swinburne’s argument in The Existence of God. I then present the problems I encountered in Swinburne’s argument, specifically problems that interfered with my attempt to arrive at values for the probabilities discussed by Swinburne. Finally, I suggest that Swinburne’s argument would be more persuasive if he assigned exact values to his probabilities.
Rebuilding the City, Leaving It Behind: Transportation and the Environmental Crisis in Turn-of-the-Century American Cities

As U.S. cities burgeoned in the late nineteenth century, their environmental problems multiplied. In response, some urban elites worked to rebuild the city to alleviate its environmental ills; othe...
Optimization issues in multimedia systems

Multimedia systems must meet stringent real-time performance criteria in order to satisfy customer requirements. Because of these criteria, and because of the rich structure inherent in video-on-demand (VOD) applications, there is both need and opportunity to employ sophisticated mathematical optimization techniques. In this paper we present an overview of several recent optimization algorithms for multimedia systems, concentrating on the techniques themselves. In particular, we will describe a VOD batching algorithm known as the maximum factored queue length policy, based in part on solving a simple instance of a so-called mathematical resource allocation problem. Next we will describe an optimization problem arising when employing a VOD technique known as adaptive piggybacking. This problem can be solved as a dynamic program, and the scheme which results is known as the snapshot algorithm. Finally we will describe a so-called DASD dancing algorithm for VOD disk load balancing, which depends on the solution to a set of three somewhat more advanced resource allocation problems. © 1998 John Wiley & Sons, Inc.
Adaptive polynomial filters

Adaptive nonlinear filters equipped with polynomial models of nonlinearity are explained. The polynomial systems considered are those nonlinear systems whose output signals can be related to the input signals through a truncated Volterra series expansion or a recursive nonlinear difference equation. The Volterra series expansion can model a large class of nonlinear systems and is attractive in adaptive filtering applications because the expansion is a linear combination of nonlinear functions of the input signal. The basic ideas behind the development of gradient and recursive least-squares adaptive Volterra filters are first discussed. Adaptive algorithms using system models involving recursive nonlinear difference equations are then treated. Such systems may be able to approximate many nonlinear systems with great parsimony in the use of coefficients. Also discussed are current research trends and new results and problem areas associated with these nonlinear filters. A lattice structure for polynomial models is described. >
Effect of inhaled iloprost on the exercise function of Fontan patients: A demonstration of concept

Background Exercise capacity following Fontan surgery is often depressed. An inability to reduce pulmonary vascular resistance appropriately during exercise may contribute to this phenomenon. The aim of this study was to determine whether administration of iloprost, a selective pulmonary vasodilator, would improve exercise function after Fontan procedure.
New proofs of identities of Lebesgue and Göllnitz via tilings

In 1840, V.A. Lebesgue proved the following two series-product identities:@?n>=0(-1;q)"n(q)"nq^(^n^+^1^2^)[email protected]?n>=11+q^2^n^-^11-q^2^n^-^1,@?n>=0(-q;q)"n(q)"nq^(^n^+^1^2^)[email protected]?n>=11-q^4^n1-q^n. These can be viewed as specializations of the following more general result:@?n>=0(-z;q)"n(q)"nq^(^n^+^1^2^)[email protected]?n>=1(1+q^n)(1+zq^2^n^-^1). There are numerous combinatorial proofs of this identity, all of which describe a bijection between different types of integer partitions. Our goal is to provide a new, novel combinatorial proof that demonstrates how both sides of the above identity enumerate the same collection of ''weighted Pell tilings.'' In the process, we also provide a new proof of the Gollnitz identities.
Effect of heat on viral protein production and budding in cultured mammalian cells.

The life cycle of enveloped viruses is intimately associated with, and influenced by, host cell membrane organization, which is altered by hyperthermia. Hyperthermia-modified Moloney murine leukaemia virus (M-MuLV) release, protein production and intracellular protein processing in a chronically infected cultured murine cell line, C9CL98 (C9). Both 44°C/45 min and 42–8°C/135 min substantially decreased cell-free viral env protein 8–48 h postheating, but virus release and cellular viral protein content increased following 42–8°C/25 min. Proteolytic processing of viral Pr65 gag precursor to p30 gag protein, normally observed within unheated C9 cells, was blocked for at least 8 h after 44°C/45 min. Virus released from heated C9 veils was as infectious to NIH/3T3 cells as was virus from control cells. Cells surviving exposure to 42 · 8°C/135 min became thermotolerant to decreased virus release from a second heating if delivered 10–48 h after the initial heating. The mechanism by which virus release is blocked...
Teacher leaders as equity-centered change agents: exploring the conditions that influence navigating change to promote educational equity

As inequities continue to be present for students of color, for English-language learners, for students from low-income households, for LGBTQ students and for students with disabilities, schools must find ways to increase achievement and high expectations for all students. Although not explored thoroughly in the research literature, teacher leaders (TLs) can be key change agents in developing more equitable schools. The purpose of this qualitative study was to examine the work of equity-centered TLs who facilitated professional learning on their campuses in relation to equity issues. Particularly, this study looked at the facilitators and inhibitors for TLs spearheading change and how they navigate these conditions. Data sources included reflection journals, class assignments and interviews. Findings indicate that TLs facilitating change for equity in schools with unsupportive conditions (i.e. fear, lack of principal support) found these conditions served as barriers for teachers to address inequities. Th...
African American Women’s Breastfeeding Experiences Cultural, Personal, and Political Voices

The low rate of breastfeeding among African American women in the United States is a poorly understood, persistent disparity. Our purpose in this study was to gain an understanding of how African American women experience breastfeeding in the context of their day-to-day lives. The Sequential-Consensual Qualitative Design (SCQD), a 3-stage qualitative methodology aimed at exploring the cultural, personal, and political context of phenomena, was used to explore the experiences of African American women who felt successful with breastfeeding. An integration of qualitative content analysis and Black feminist theory was used to analyze the data. Themes that emerged from Stage-2 data analysis included self-determination, spirituality and breastfeeding, and empowerment. In Stage 3 of the study, participant recommendations regarding breastfeeding promotion and support initiatives for African American breastfeeding were categorized into three themes, including engaging spheres of influence, sparking breastfeeding activism, and addressing images of the sexual breast vs. the nurturing breast.
Clinical Use of Tolmetin Sodium in Patients with Ankylosing Spondylitis: A Review

The efficacy and safety of tolmetin sodium in the management of ankylosing spondylitis are presented in a review of published and unpublished data. In both open and controlled clinical studies, tolmetin was superior to placebo and equal to indomethacin in its capacity to relieve pain, inflammation, and other symptoms of ankylosing spondylitis (AS). Objective and subjective assessments showed that both tolmetin sodium and indomethacin provided significant therapeutic benefits to patients with AS. In AS, the two drugs showed similar adverse reaction profiles. Adverse reactions with both drugs were minimal and predominantly affected the gastrointestinal tract; in most cases these symptoms cleared spontaneously without discontinuing the drugs.
Reconfigurable terahertz frequency selective structures using vanadium dioxide

Terahertz frequency selective surfaces with tunable characteristics are presented. Vanadium dioxide patches and metallic resonators were used. Vanadium dioxide behaves as an insulator at low temperatures and as a metal at high temperatures with transition temperature of ~ 68°C. Single to dual polarized bandpass FSS structure at 0.5 THz and tunable bandpass FSS structure were realized. We measured extinction ratio of 25 dB for the polarizer and 31% shift in the resonance frequency for the FSS.