cssi/SciSciGPT-SciSciNet huggingface dataset:
Retinoid-X Receptor Agonists Increase Thyroid Hormone Competence in Lower Jaw Remodeling of Pre-Metamorphic Xenopus laevis tadpoles

Thyroid hormone (TH) signaling plays critical roles during vertebrate development, including regulation of skeletal and cartilage growth. TH acts through its receptors (TRs), nuclear hormone receptors (NRs) that heterodimerize with Retinoid-X receptors (RXRs), to regulate gene expression. A defining difference between NR signaling during development compared to in adult tissues, is competence, the ability of the organism to respond to an endocrine signal. Amphibian metamorphosis, especially in Xenopus laevis, the African clawed frog, is a well-established in vivo model for studying the mechanisms of TH action during development. Previously, we have used one-week post-fertilization X. laevis tadpoles, which are only partially competent to TH, to show that in the tail, which is naturally refractive to exogenous T3 at this stage, RXR agonists increase TH competence, and that RXR antagonism inhibits the TH response. Here, we focused on the jaw that undergoes dramatic TH-mediated remodeling during metamorphosis in order to support new feeding and breathing styles. We used a battery of approaches in one-week-old tadpoles, including quantitative morphology, differential gene expression and whole mount cell proliferation assays, to show that both pharmacologic (bexarotene) and environmental (tributyltin) RXR agonists potentiated TH-induced responses but were inactive in the absence of TH; and the RXR antagonist UVI 3003 inhibited TH action. At this young age, the lower jaw has not developed to the point that T3-induced changes produce an adult-like jaw morphology, and we found that increasing TH competence with RXR agonists did not give us a more natural-metamorphic phenotype, even though Bex and TBT significantly potentiated cellular proliferation and the TH induction of runx2, a transcription factor critical for developing cartilage and bone. Prominent targets of RXR-mediated TH potentiation were members of the matrix metalloprotease family, suggesting that RXR potentiation may emphasize pathways responsible for rapid changes during development.
Interprofessional Continuous Glucose Monitoring for Underserved Adults with Type 2 Diabetes on Insulin or Secretagogues

Background: Literature describing continuous glucose monitoring for underserved patients, including those with type 2 diabetes or at risk for hypoglycemia, is lacking. Methods: An interprofessional internal medicine residency team implemented a blinded CGM service for underserved adults with type 2 diabetes with at-goal glycated hemoglobin (A1C) taking insulin or secretagogues. Results: The 2-week blinded CGM service (N=44) significantly reduced time in hypoglycemia (<70 mg/dL) by 4.1% (P=0.0038). Time-in-target-range increased significantly (4.31%, P=0.025). Body weight, number of medications, and daily insulin dose decreased significantly. Overall, A1C remained stable, indicating no worsening of diabetes control associated with the service. Conclusions: The interprofessional blinded CGM service influenced improved glycemic control in this vulnerable population.
The bootstrap approach to clustering

A very difficult problem in cluster analysis is to determine the number of clusters present in a data set. Most clustering algorithms can partition a data set into any specified number of clusters even if the data set has no cluster structure. Unfortunately, it is very hard to decide if a K-cluster structure makes sense for the given data set.
Electrochemistry of Copper

The sections in this article are Introduction Oxidation States of Copper Reference Standards for Potential Values in Nonaqueous Solvent Studies Methods Used for Potential Measurements Potentials Involving Solvated Copper Species Electrochemical Considerations for Copper(II/I) Complexes Involving Multidentate Ligands Trends in Potentials of Copper(II/I) Complexes with Multidentate Ligands Dependence of Copper(II/I) Potentials on Ligand Properties Correlation of Potentials to Copper(II) Complex Stability Constants Mechanistic Aspects of Copper(II/I) Electron Transfer Ligand Conformational Change Complex Dissociation/Formation Interconversion of Ternary and Binary Complexes Interconversion of 1:2 and 1:1 Complexes Dimeric/Monomeric Species Other Phenomena Affecting Electrochemical Behavior Ligand Oxidation or Reduction Electroplating of Copper Biological Copper Systems Other Copper(II/I) Systems Unidentate Ligand Complexes Hydroxide Complexes Halide Complexes Cyanide and Thiocyanate Complexes Ammonia Complexes Complexes with Acetate and Other Common Bronsted Bases Noncomplexing Buffer Systems Binuclear Complexes Copper(III/II) Systems
The U, B, V, R, and I Extinctions in Four Areas of the Southern Coalsack

From star counts the extinctions in five spectral bands were determined for four areas of the Southern Coalsack. The wavelength dependence of the extinction values follows the Whitford curve. Minimum masses for six globules are given.
Weakly Polar Interactions In Proteins

Publisher Summary This chapter reviews the subject of noncovalent interactions in proteins with particular emphasis on the so-called weakly polar interactions. The chapter discusses the physical bases of the noncovalent electrostatic interactions that stabilize protein structure and the four types of weakly polar interactions that have been shown to occur in proteins are described with reference to some biologically significant examples of protein structure stabilization and protein–ligand binding. Atomic multipoles are estimated by fitting the atomic multipole expansion to the detailed features of the ground-state wave function obtained from ab initio quantum mechanical calculations. The amino acids phenylalanine, tyrosine, and tryptophan are traditionally grouped because their side chains are aromatic. The weakly polar nature of aromatic residues that leads to their interaction with oxygen and sulfur atoms suggests that they ought to be able to interact with themselves as well. Aromatic–aromatic interactions also play an important role in protein–ligand binding. The physical characteristics of noncovalent electrostatic interactions that stabilize protein structure have been described. In addition, an unusual group of weak electrostatic interactions in proteins, which have only recently been characterized, have been reviewed in detail and some examples of biological importance cited. These interactions, termed “weakly polar,” result from the characteristic distribution of partial charges in some amino acid side chain moieties and involve interactions among electronic monopole, dipole, and quadrupole moments.
Targeting glycogen metabolism in bladder cancer

Metabolism has been a heavily investigated topic in cancer research for the past decade. Although the role of aerobic glycolysis (the Warburg effect) in cancer has been extensively studied, abnormalities in other metabolic pathways are only just being understood in cancer. One such pathway is glycogen metabolism; its involvement in cancer development, particularly in urothelial malignancies, and possible ways of exploiting aberrations in this process for treatment are currently being studied. New research shows that the glycogen debranching enzyme amylo-α-1,6-glucosidase, 4-α-glucanotransferase (AGL) is a novel tumour suppressor in bladder cancer. Loss of AGL leads to rapid proliferation of bladder cancer cells. Another enzyme involved in glycogen debranching, glycogen phosphorylase, has been shown to be a tumour promoter in cancer, including in prostate cancer. Studies demonstrate that bladder cancer cells in which AGL expression is lost are more metabolically active than cells with intact AGL expression, and these cells are more sensitive to inhibition of both glycolysis and glycine synthesis--two targetable pathways. As a tumour promoter and enzyme, glycogen phosphorylase can be directly targeted, and preclinical inhibitor studies are promising. However, few of these glycogen phosphorylase inhibitors have been tested for cancer treatment in the clinical setting. Several possible limitations to the targeting of AGL and glycogen phosphorylase might also exist.
Synthesis of highly nanoporous YBO3 architecture via a co‐precipitation approach and tunable luminescent properties

We present a simple co-precipitation method to prepare highly nanoporous YBO(3) architecture using NaBO(3) · 4H(2)O as a boric source and 600°C as the annealing temperature. The reaction was carried out under an aqueous condition without any organic solvent, surfactant, or catalysts. The prepared samples were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The photoluminescence of doped-nanoporous YBO(3):Eu(3+) was further investigated. It is expected that highly nanoporous YBO(3) architecture can be an ideal candidate for applications in catalysis, adsorption, and optoelectronic devices.
Efficient DCT domain implementation of picture masking and compositing

An efficient method for implementing picture masking and compositing in the DCT domain is presented. The method is based on representing the masking function in terms of the DCT basis functions and computing the masking as a weighted sum of the results of masking by the DCT basis functions. In the DCT domain, masking by the DCT basis functions has very simple and efficient implementation. Because of the energy compaction property of the DCT, the weight of many of the basis functions is very small and can be dropped from the weighted sum without introducing noticeable artifacts. This leads to very efficient implementations for the masking and compositing images in the DCT domain, typically requiring less than 3 multiplications per pixel.
Infrared Techniques for Comet Observations

The infrared spectral region (1–1000 µm) is important for studies of both molecules and solid grains in comets. Infrared astronomy is in the midst of a technological revolution, with the development of sensitive 2-dimensional arrays leading to infrared cameras and spectrometers with vastly improved sensitivity and resolution. The Halley campaign gave us tantalizing first glimpses of the comet science possible with this new technology, evidenced, for example, by the many new spectral features detected in the infrared. The techniques of photometry, imaging, and spectroscopy are reviewed in this chapter and their status at the time of the Halley observations is described.
Critic's Choice Essay: Pollination Ecology of Our Native Prairie Plants

The Oklahoma prairie in the summer is an ideal place and time to study pollination ecology. With its "cornucopia" pattern of flowering, where many plants flower synchronously, it has many flowers available every day. This past summer at the Oklahoma Department of Wildlife Conservation's Arcadia Conservation Education Area, Dr. Rebecca Pace, an entomologist, and I taught a course in pollination ecology for the University of Central Oklahoma.
Neurocontroller with adaptable activation function for power system studies

In this paper the performance of a neural network with an activation function with constant and adaptable slope is presented. Later the network can be used as a neurocontroller to estimate the state and isolate the faulty power system from the rest of the system. The method is illustrated with an example. >
The Endoscopic Endonasal Approach for Removal of Petroclival Chondrosarcomas

Chondrosarcomas of the skull base are rare, locally invasive tumors that typically arise in the petroclival region, from degenerated chondroid cells located within the synchondrosis. Given their usually slow growth rate, they are capable of reaching sizable dimensions, promoting bone erosion and significant displacement of neurovascular structures before causing symptomatology that will eventually lead to diagnosis; cranial neuropathies and headaches are common complaints. This article discusses the pertinent surgical anatomy, patient selection criteria, technical nuances and complication management of the endonasal resection of skull base chondrosarcomas.
Wing Configuration Impact on Design Optimums for a Subsonic Passenger Transport

This study sought to compare four aircraft wing configurations at a conceptual level using a multi-disciplinary optimization (MDO) process. The MDO framework used was created by Georgia Institute of Technology and Virginia Polytechnic Institute and State University. They created a multi-disciplinary design and optimization environment that could capture the unique features of the truss-braced wing (TBW) configuration. The four wing configurations selected for the study were a low wing cantilever installation, a high wing cantilever, a strut-braced wing, and a single jury TBW. The mission that was used for this study was a 160 passenger transport aircraft with a design range of 2,875 nautical miles at the design payload, flown at a cruise Mach number of 0.78. This paper includes discussion and optimization results for multiple design objectives. Five design objectives were chosen to illustrate the impact of selected objective on the optimization result: minimum takeoff gross weight (TOGW), minimum operating empty weight, minimum block fuel weight, maximum start of cruise lift-to-drag ratio, and minimum start of cruise drag coefficient. The results show that the design objective selected will impact the characteristics of the optimized aircraft. Although minimum life cycle cost was not one of the objectives, TOGW is often used as a proxy for life cycle cost. The low wing cantilever had the lowest TOGW followed by the strut-braced wing.
A mechanistic view of binary colloidal superlattice formation using DNA-directed interactions

The use of grafted, single-stranded DNA oligomer brushes with engineered sequences to effect tunable interactions between colloidal particles has now been demonstrated experimentally in both nano- and microscale systems. The versatility of this technology is highly appealing for realizing self-assembly of complex structures. However, ambiguities remain regarding how operating conditions, such as the rate at which the system temperature is reduced, interact with the other system parameters to produce crystalline assemblies with particular structures and defect densities. In this paper, a computational analysis is presented for the crystallization of binary superlattice crystals comprised of sub-micron colloidal spheres using a realistic model for the DNA-mediated interactions. The binary system consists of two populations of identical spheres that differ only in the sequence of the DNA oligomers grafted onto their surfaces. Metropolis Monte Carlo simulations and perturbation theory for free energy estimation are used to construct a detailed mechanistic picture for binary superlattice formation. The analysis reveals several interesting features of this system, particularly the role of kinetics in dictating not only the quality of the superlattice crystals, but also their crystalline structure. Using the results presented here, we make connections to recent experimental findings in similar binary crystallization systems.
Regulation of RUNX1/AML1 during the G2/M transition.

The acute myeloid leukemia 1 (AML1, RUNX1) transcription factor is a key regulator of hematopoietic differentiation both in embryonic stem cells and mature hematopoietic progenitors. The RUNX1 protein is thought to play a role in the control of progression through the cell cycle. We have shown that post-transcriptional regulation of RUNX1 activity occurs, in part, through phosphorylation. To investigate whether transit through the cell cycle is associated with changes in the phosphorylation of RUNX1, we have derived phospho-specific antibodies against three of the five major phosphorylation sites in the transcriptional activation domain of RUNX1, S276, S303 and S462. Using these antibodies we demonstrate that treatment of Jurkat T-cells with nocodazole, a G2/M blocking compound, causes an increase in phosphorylation of these three amino acids. By elutriating the Jurkat cells, we are able to demonstrate that these amino acids are normally phosphorylated at the G2/M phase of the cell cycle. Using in vivo inhibitors and in vitro assays this phosphorylation appears to be dependent on Cdk1. We find that RUNX1 degradation occurs at the G2/M–G1 transition and is regulated by both Cdc20 and phosphoryation, suggesting that the anaphase promoting complex plays a role in modifying the level of this protein. Regulation of the extent of phosphorylation of RUNX1 may play a role in controlling the degradation of the protein, implying that additional E3 ligases may also be involved.
The Relationship between Freeway Safety and Geometric Design Elements

This paper mainly quantifies the safety effects of ramp spacing, and other geometric design elements of highway facilities. Negative Binomial (NB) regression models have been applied to estimate of different accident types, including total crashes, fatal-plus-injury crashes, single-vehicle crashes and multiple-vehicle crashes. Data for model estimation was collected in 112 freeway segments where each entrance ramp is followed by an exit ramp on I-5 in the Washington State, US. Three years (2005-2007) of freeway crashes has been examined by the NB model. The modeling results have been geared into the development of accident modification factors (AMFs) for ramp spacing that can be used safety prediction of freeways. Furthermore, the results also suggest some geometric designs are recommended to improve freeway safety
First report of Blaesoxipha plinthopyga (Diptera: Sarcophagidae) from a human corpse in the U.S.A. and a new state geographic record based on specimen genotype.

Carrion flies in the taxonomic family Sarcophagidae are often recovered from a human corpse. However, because such specimens are difficult to identify, the forensic literature on this taxon is quite limited compared with that of the commonly employed Calliphoridae. Faced with a sarcophagid larva that could not be identified microscopically from a death investigation in the state of Idaho, we generated cytochrome oxidase one DNA sequence data from the specimen. Comparison to a reference data set of forensically significant sarcophagids from Canada and the U.S.A. confirmed that this was the first discovery of Blaesoxipha plinthopyga in a human corpse in the U.S.A. and the first record of this species in Idaho. Because B. plinthopyga occurs from the Northern U.S.A. to the Neotropics, it is potentially useful for estimating time since death at many locations.
Predicting Object Dynamics in Scenes

Given a static scene, a human can trivially enumerate the myriad of things that can happen next and characterize the relative likelihood of each. In the process, we make use of enormous amounts of commonsense knowledge about how the world works. In this paper, we investigate learning this commonsense knowledge from data. To overcome a lack of densely annotated spatiotemporal data, we learn from sequences of abstract images gathered using crowdsourcing. The abstract scenes provide both object location and attribute information. We demonstrate qualitatively and quantitatively that our models produce plausible scene predictions on both the abstract images, as well as natural images taken from the Internet.
Relation Between HLA-DW and the B-Lymphocyte Specificities

Homozygous DW typing cells were tested for six B-lymphocyte specificities. All four of the second locus specificities of B lymphocytes were strongly associated with the DW specificities. DW1 typing cells were B group 6, DW2 were B4, DW3 were B5, and LD107 were B3. The first B-cell locus antigens 1 and 2 tended to be uniform within the DW groups. From an analysis of the typing responses of a panel of cells to the homozygous typing cells, it has become apparent that the first B-locus specificity present on the homozygous typing cells also plays a role in determining whether a typing response is obtained or not. Thus, the DW3 typing cells were themselves B2 and B5, and cells having B2-B5 were most frequently nonreactive to DW3 in mixed lymphocyte culture. Homozygous typing cells therefore mainly detect the second B-cell locus antigens and, to a lesser degree, the first locus specificities. Stated another way, homozygous typing cells do not define a single specificity, but rather the presence of two B-lymphocyte specificities, even though their responses often reflect matching of only the second B-locus specificity.
Structural Dynamics of Troponin I during Ca2+-Activation of Cardiac Thin Filaments: A Multi-Site Förster Resonance Energy Transfer Study

A multi-site, steady-state Forster resonance energy transfer (FRET) approach was used to quantify Ca2+-induced changes in proximity between donor loci on human cardiac troponin I (cTnI), and acceptor loci on human cardiac tropomyosin (cTm) and F-actin within functional thin filaments. A fluorescent donor probe was introduced to unique and key cysteine residues on the C- and N-termini of cTnI. A FRET acceptor probe was introduced to one of three sites located on the inner or outer domain of F-actin, namely Cys-374 and the phalloidin-binding site on F-actin, and Cys-190 of cTm. Unlike earlier FRET analyses of protein dynamics within the thin filament, this study considered the effects of non-random distribution of dipoles for the donor and acceptor probes. The major conclusion drawn from this study is that Ca2+ and myosin S1-binding to the thin filament results in movement of the C-terminal domain of cTnI from the outer domain of F-actin towards the inner domain, which is associated with the myosin-binding. A hinge-linkage model is used to best-describe the finding of a Ca2+-induced movement of the C-terminus of cTnI with a stationary N-terminus. This dynamic model of the activation of the thin filament is discussed in the context of other structural and biochemical studies on normal and mutant cTnI found in hypertrophic cardiomyopathies.
The occurrence of fossil seagrasses in the Avon Park formation (late middle eocene), Levy County, Florida (U.S.A.)

Abstract Within the Avon Park Formation of west-central Florida, U.S.A., fossil seagrasses are preserved as carbonized imprints within the bedding planes of a micritic dolomitized limestone. Six species could be recognized, but only for three of them was the material sufficiently complete to allow a formal description. These three species are Thalassodendron auricula - leporis den Hartog n.sp., Cymodocea floridana den Hartog n.sp. and Thalassia testudinum Banks ex Konig. The genera Thalassodendron and Cymodocea have not been recorded for America before.
Inversion Using Bayesian Hyper-Prior Formulation For Sharp Boundaries

Geological discontinuities commonly occur in nature. Sharp jumps such as distinct layering or formation of localized bodies in the subsurface can occur due to various geological processes. However, the bandwidth of the geophysical signals such as seismic or electromagnetics probing the Earth often produces smooth representations of the model via imaging or inversion. Introducing informative priors through regularization process has been shown to produce discontinuous model. Among the various classes of the regularization operators that preserve discontinuity are total variation norm, compactness constraints and Lp norm such as sparse spike solutions. In this paper we focus on a Bayesian hyper model formulation originally developed for image processing applications to geophysical inversion of the data. Both the locations and the magnitude of the discontinuities are considered unknowns which are commonly encountered in practical applications. Using a series of examples we compare this approach with other well known approaches such as total variation and L1 inversion in the wavelet domain.
Integrating Motivating and Constraining Forces in Deviance Causation: A Test of Causal Chain Hypotheses in Control Balance Theory

ABSTRACT A major innovation in control balance theory is the integration of motivating and constraining forces into a “causal chain” explanation of deviance. To test these relationships, this research presents a parsed model of the causal chain that focuses on the associations among control ratios, deviant motivation, situational provocations, constraint, and deviant behavior. Results from a first-person scenario testing hypotheses from this model show that, as predicted, control ratios affect deviance both directly and indirectly through motivating and constraining variables. While the full model explains about 39% of the variation in deviance, control ratios do not, however, show great explanatory power regarding variation in motivation and constraint.
Response to a relational agent by hospital patients with depressive symptoms

Depression affects approximately 15% of the US population, and is recognized as an important risk factor for poor outcomes among patients with various illnesses. Automated health education and behavior change programs have the potential to help address many of the shortcomings in health care. However, the role of these systems in the care of patients with depression has been insufficiently examined. In the current study, we sought to evaluate how hospitalized medical patients would respond to a computer animated conversational agent that has been developed to provide information in an empathic fashion about a patient's hospital discharge plan. In particular, we sought to examine how patients who have a high level of depressive symptoms respond to this system. Therapeutic alliance - the trust and belief that a patient and provider have in working together to achieve a desired therapeutic outcome - was used as the primary outcome measure, since it has been shown to be important in predicting outcomes across a wide range of health problems, including depression. In an evaluation of 139 hospital patients who interacted with the agent at the time of discharge, all patients, regardless of depressive symptoms, rated the agent very high on measures of satisfaction and ease of use, and most preferred receiving their discharge information from the agent compared to their doctors or nurses in the hospital. In addition, we found that patients with symptoms indicative of major depression rated the agent significantly higher on therapeutic alliance compared to patients who did not have major depressive symptoms. We conclude that empathic agents represent a promising technology for patient assessment, education and counseling for those most in need of comfort and caring in the inpatient setting.
Carbon-13 spin-lattice relaxation in organometallic complexes

Abstract The result of inversion recovery spin-lattice relaxation time ( T 1 ) measurements on 19 selected organometallic half-sandwich and sandwich complexes of Cr, Mn, Fe and Co are reported together with their 13 C NMR data. Large variations of the 13 C NMR T 1 values for C 5 H 5 and CO moieties are observed, depending on field strength, temperature and solvent. The use of high field instruments usually leads to lower 13 C NMR T 1 values for these groups, but in certain cases the values for quaternary carbon atoms increase.
Marginal adaptation of castable ceramic crowns

Tooth preparations and seating techniques of castable ceramic crowns differ from metal ceramic crowns. This study evaluated the variable effects of cementation on the marginal adaptation of Dicor, Cerestore, and porcelain-fused-to-metal crowns. The shoulder preparation was maintained for ceramic crowns, and a cavosurface bevel was designed for metal ceramic crowns. Crowns were made with a replication size of 10, placed on master dies, and the marginal openings measured with a Nikon Measurescope 20 instrument. Thirty crowns were cemented with zinc phosphate cement and the recommended clinical force. Marginal adaptation was not improved with a gingival bevel preparation or an increased seating force. The best marginal adaptation was recorded for Cerestore crowns.
Estrogen as a Neuroprotective Agent in the Treatment of Spinal Cord Injury

The following review is a brief discussion about spinal cord injury and the possibility of using estrogen as a neuroprotective agent. There are several pathways by which secondary cell death can occur following spinal cord injury, including infiltration of inflammatory cells, generation of reactive oxygen species, decreases in spinal cord blood flow, and increases in intracellular Ca(2+) levels. This secondary damage leads to apoptotic cell death, and the neuroprotective effects of pharmacologic agents have been investigated using experimentally induced spinal cord injury in animals. Currently, only high-dose methylprednisolone is advocated for the treatment of patients following spinal cord injury. Estrogen has been shown to be neuroprotective in both in vitro and in vivo studies. There are several possible mechanisms of action by which estrogen may attenuate damage following spinal cord injury and improve functional outcome. Estrogen has been shown to have anti-inflammatory properties. Estrogen levels are correlated with an increase in post-traumatic blood flow to injured tissue. Estrogen may also upregulate protein levels of anti-apoptotic Bcl-2 and may attenuate the post-traumatic influx of Ca(2+).
Short-range anisotropic ferromagnetic correlations in the paramagnetic and antiferromagnetic phases of Gd5Ge4

Signatures of short range anisotropic ferromagnetic correlations and ferromagnetic clustering, manifested as unusually large hysteresis and other anomalies of the low magnetic field dc magnetization and ac magnetic susceptibility, have been observed in both the antiferromagnetic and paramagnetic states of single crystal ${\mathrm{Gd}}_{5}{\mathrm{Ge}}_{4}$. Ferromagnetic correlations, which are most pronounced in a weak magnetic field applied along the $b$ axis, are readily suppressed by fields exceeding $\ensuremath{\sim}5\phantom{\rule{0.3em}{0ex}}\mathrm{kOe}$ and are believed to be related to a Griffiths-like phase that develops in ${\mathrm{Gd}}_{5}{\mathrm{Ge}}_{4}$ below ${T}_{\mathrm{G}}\ensuremath{\cong}240\phantom{\rule{0.3em}{0ex}}\mathrm{K}$.
Microwave photonics: Recent programs at DARPA

Microwave photonic components and systems are of significant interest to radar and communications systems used on military platforms. This paper highlights recent experimental results and system architectures aimed at moving microwave photonic component developments to system demonstrations and transitions to deployed military systems.
Stagnation Flow in Streamer Boundaries

It is possible for flow tubes adjacent to closed magnetic field lines on the boundaries of streamers to have spreading factors that change rapidly according to height. Mathematical models in this thin layer are prone to uncertainties. In this paper we use an analytical model of magnetically closed and adjacent open regions to calculate the spreading factor close to the closed field lines and near the flow on the open field lines. We recovered the shape of the closed field region, or helmet, and show the evolution of the helmet under increasing temperature. We also show why and when stagnation flow can occur in the area of the cusp at the top of the helmet.
Spatial and temporal organization of calcium signalling in hepatocytes.

Abstract Treatment of hepatocytes with agonists which act via the second messenger inositol 1,4,5-trisphosphate (Ins(1,4,5)P 3 ), results in increases of cytosolic free Ca 2+ ([Ca 2+ ] i ) which are manifest as a series of discrete [Ca 2+ ] i transients or oscillations. With increasing agonist dose [Ca 2+ ] i osciliation frequency increases and the initial latent period decreases, but the amplitude of the [Ca 2+ ] i oscillations remains constant. Studies of these [Ca 2+ ] i oscillations at the subcellular level have indicated that the [Ca 2+ ] i changes do not occur synchronously throughout the cell, but initiate at a specific subcellular domain, adjacent to a region of the plasma membrane, and then propagate through the cell as a [Ca 2+ ] i wave. For a given cell, the locus of [Ca 2+ ] i wave initiation is constant for every oscillation in a series and is also identical when the cell is sequentially stimulated with different agonists or when the phospholipase C-linked G protein is activated directly using AIF 4 − . The kinetics of the [Ca 2+ ] i waves indicate that a Ca 2+ -activated mechanism is involved in propagating the oscillatory [Ca 2+ ] i increases throughout the cell, and the data appear to be most consistent with a process of Ca 2+ -induced Ca 2+ release. It is proposed that the ability to propagate [Ca 2+ ] i oscillations into regions of the cell distal to the region in which the signal transduction apparatus is localized could serve an important function in allowing all parts of the cell to respond to the stimulus.
Design of Animal Carcinogenicity Studies for Goodness-of-Fit of Multistage Models

The effect of bioassay design changes on the variability of risk estimates in the experimental dose region is investigated. Three-dose designs with a control group and other "usual" designs utilizing 200 animals are studied in detail. Constraints on the minimum power of the linear trend test in proportions are used to eliminate designs with unacceptable power. An acceptable design region is compared to designs aimed at improving the low dose extrapolation. A group of designs acceptable for a range of objectives is proposed.
Chorismate mutase isoenzymes from Sorghum bicolor: Immunological characterization

Highly purified fractions of chorismate mutase 1 and 2 from etiolated seedlings of Sorghum bicolor were used as the antigen for antibody production in BALB/c mice. Tests for antigen-antibody complex formation were made by immunodiffusion, immunoprecipitation, and enzyme-linked immunosorbent assay (ELISA). These tests indicated the presence of specific antibodies for each isoenzyme in their antisera. However, in the same tests, no cross-reaction was found between chorismate mutase 1 and 2 and their antisera. This indicates no immunological similarity between the two isoenzymes of chorismate mutase from sorghum.
Permeability of Fabric Ground Covers to Organically-Derived Nutrients

Ground covers can reduce fruit production costs. However, because they differ in porosity, they can pose an obstacle for in-season fertilization. An incubation experiment was established using soil columns with two different covers amended with solid organic fertilizers to determine movement of nutrients into the soil. One cover was porous while the other was tightly woven. The porous cover was slightly more (105%) conductive to organic carbon than the woven. Both were less conductive than bare soil (84%—porous cover and 80%—woven cover). Later, nutrients passed both covers similarly. Covers reduced nitrogen passage from 62% to 71% of bare soil rates. Porous, woven, and bare soil transmitted 6.5%, 7.4%, and 7.9% of added phosphorus. β-glucosidase was similar in all treatments, indicating the biological environment was not altered. Initially, the woven cover was hydrophobic but later passed nutrients, presumably due to organic coatings on the cover. Results show the potential of adding nutrients through gr...
Cytochalasin B: Effects on membrane ruffling, growth cone and microspike activity, and microfilament structure not due to altered glucose transport

Abstract Cytochalasin inhibits transport of deoxyglucose by 96–98% in glial and nerve cells. Incubation of such cells in glucose-free medium does not alter cell behavior associated with locomotion or axon elongation, as contrasted to the effects of CB treatment. In addition, micro-filaments of ruffled membranes and growth cones are also not altered by glucose-free conditions.
Selective Impairment of Inhibition After TBI in Children

Inhibition was studied in 12 children who had sustained a severe traumatic brain injury (TBI) at least 1 year earlier and in 15 control children. On the flanker task, which involved pressing a button corresponding to the direction of an arrow, the TBI group performed less accurately than controls under interference (flankers were incongruent with arrow) and go-no-go (adjacent stimulus signaled child to withhold response) conditions, but not neutral or facilitation (flankers were congruent) conditions. Response latency was related to age and task condition, but not to group. Severe TBI in children may disrupt development of distributed networks mediating inhibition.
Radiochemical determination of damage profiles in silicon

Abstract A novel technique for the study of structural damage incurred by single crystal silicon targets during ion implantation is described. The method is based upon copper-decoration of the vacancy rich damaged region, followed by radiochemical measurement of the resulting copper distribution. Utilizing neutron activation, sharply peaked radiocopper profiles are obtained, which are believed to represent the depth distributions of large, relatively immobile defects such as vacancy clusters, voids, or crystalline faults. A more efficient decoration of isolated vacancy-type defects is realized when Wu is employed as a radioisotopic tracer in the decoration step, however, the rapid diffusivity of these smaller species leads to less sharply defined radiocopper profiles. Both the neutron activation and radiotracer modifications of the technique yield damage profiles which are significantly shallower than the corresponding implanted impurity profiles.
Stimulatory effect of splicing factors on transcriptional elongation.

Transcription and pre-mRNA splicing are tightly coupled gene expression events in eukaryotic cells1,2. An interaction between the carboxy-terminal domain of the largest subunit of RNA polymerase (Pol) II and components of the splicing machinery is postulated to mediate this coupling3,4,5. Here, we show that splicing factors function directly to promote transcriptional elongation, demonstrating that transcription is more intimately coupled to splicing than previously thought. The spliceosomal U small nuclear ribonucleoproteins (snRNPs) interact with human transcription elongation factor TAT-SF1 (refs 6,7,8,9) and strongly stimulate polymerase elongation when directed to an intron-free human immunodeficiency virus-1 (HIV-1) template. This effect is likely to be mediated through the binding of TAT-SF1 to elongation factor P-TEFb10, a proposed component of the transcription elongation complex11,12. Inclusion of splicing signals in the nascent transcript further stimulates transcription, supporting the notion that the recruitment of U snRNPs near the elongating polymerase is important for transcription. Because the TAT-SF1–U snRNP complex also stimulates splicing in vitro, it may serve as a dual-function factor to couple transcription and splicing and to facilitate their reciprocal activation.
Guernica and Total War – By Ian Patterson

Guernica, elevated in fame by Pablo Picasso's painting, fits the Harvard Profiles in History Series's focus on iconic events. It also provides author Ian Patterson with a cultural touchstone from w...
The Merits and Demerits of Pleasure in Kinesiology

What role should pleasure play in kinesiology? Although pleasure is an important concept in kinesiology, the strengths, weaknesses, and dangers of this concept have not been properly clarified. Douglas Booth and Richard Pringle have both recently scolded kinesiologists over the issue of pleasure in kinesiology with decidedly mixed results. They insist that the importance of pleasure has been neglected, and that the role that human culture plays in properly understanding pleasure in kinesiology, has been underestimated. Booth (2009) argues that “puritanical” prohibitions have made pleasure suspect. Pringle (2010) argues that kinesiologists must remember that “many students are not currently gaining a love for movement in their [physical education] experiences” (p. 130). Each scholar's suspicion of traditional distinctions between “good and bad physical pleasures” (Booth, 2009, p. 148) results in an untenable commitment to pleasure as an intrinsic good. In short, their views are hedonistic. Although Booth a...
RET proto-oncogene testing in infants presenting with Hirschsprung disease identifies 2 new multiple endocrine neoplasia 2A kindreds

Background: Multiple endocrine neoplasia 2A (MEN 2A) is a genetic syndrome manifesting as medullary thyroid carcinoma (MTC), hyperparathyroidism, and pheochromocytoma. Multiple endocrine neoplasia 2A results from mutations in the RET proto-oncogene. Hirschsprung disease (HSCR) is a rare manifestation of MEN 2A and has been described in known MEN 2A families. Methods: Here we describe 2 MEN 2A families that were only identified after the diagnosis of HSCR. Results: Kindred 1: A boy presented in infancy with HSCR. Genetic screening revealed a C609Y mutation, which is consistent with MEN 2A. Evaluation of his sister, father, and grandmother revealed the same mutation. All 3 had thyroidectomies demonstrating C-cell hyperplasia. The grandmother had a microscopic focus of MTC.Kindred 2: An infant boy and his sister were diagnosed with HSCR as neonates. Genetic testing demonstrated a C620R gene mutation consistent with MEN 2A. Total thyroidectomies revealed metastatic MTC in the father and C-cell hyperplasia in both children. Conclusions: Hirschsprung disease can be the initial presentation of MEN 2A. We strongly recommend that genetic screening be performed in patients presenting with HSCR, looking for the known RET mutations associated with MEN 2A. If a mutation consistent with MEN 2A is detected, genetic screening of all first-degree relatives in the kindred is recommended.
Effective mass and mobility of holes in strained Si/sub 1-x/Ge/sub x/ layers on

The directional density-of-state effective masses of the valence bands of a strained Si/sub 1-x/Ge/sub x/ layer for the
The effect of gradually increased blood flow on ischemia-reperfusion injury in rat kidney

Background: Gradually increased blood flow to the ischemic rat kidney was studied to assess the ability to diminish ischemia-reperfusion injury. Methods: The left renal artery and vein were isolated in 25 rats. Microclamps were applied for 45 minutes and were released at once (group II) or gradually (group III). Renal arterial blood flow and K+ activity were measured. Bilateral kidneys were harvested for histopathology and for malonyldealdehyde and myeloperoxidase levels. Results: Increased K+ activity returned to preischemic values faster in group III than in group II. No statistically significant difference existed in malonyldealdehyde and myeloperoxidase levels; histopathologic scoring showed less tissue damage in group III (P <.05). Contralateral kidney samples showed signs of ischemia in group II. Conclusions: Gradually increased blood flow to the ischemic kidney decreases ischemic changes. Ischemic insult to 1 kidney causes histopathologically detectable changes to the contralateral kidney, which can be diminished by gradual reperfusion.
Microprocessor uses in a timeshared facility

A number of topics are discussed that are related to developing computer-controlled laboratories in which microprocessors and host machines interact. Experiences are derived from work at the Learning Research and Development Center, University of Pittsburgh.
Ab Initio Time-Domain Study of Phonon-Assisted Relaxation of Charge Carriers in a PbSe Quantum Dot

The phonon-induced relaxation dynamics of charge carriers in a PbSe quantum dot is studied for the first time by ab initio density functional theory in the time-domain. The picosecond time scale of the relaxation and the absence of the phonon bottleneck are rationalized by relatively high electron and hole state densities. While many of these states show only weak optical activity, most of them participate in the electron-vibrational relaxation. Our simulations demonstrate that the slight asymmetry in the electron and hole band structure is sufficient to allow symmetry-forbidden S-P, P-S, etc. transitions, which are seen in the experimental absorption spectra. The relaxation is nonexponential, in agreement with the strongly non-Lorentzian spectral line shapes observed in experiments. The energy exchanged during individual transitions is typically greater than the characteristic phonon energy, indicating that the transitions are multiphonon. Both electrons and holes interact better with low-frequency acoustic phonons, rather than higher frequency optical modes. Holes decay only slightly faster than electrons, rendering the hole-assisted Auger relaxation pathways inefficient. This relatively symmetric vibrational relaxation of electrons and holes proceeds on a picosecond time scale, much slower than the ultrafast highly efficient carrier multiplication that was reported recently in relation to improved solar power conversion.
Symmetry in square contingency tables: tests of hypotheses and confidence interval construction.

Bowker's test, a generalization of McNemar's test, performs well under the hypothesis of symmetry, but the estimator of variance used in the test is biased when the table is asymmetric and this calls into question the test's performance in non-null situations. We seek an alternative to Bowker's test in search of methods for simultaneous inference that are valid when the hypothesis of symmetry is false. We apply multivariate normal theory to develop chi-square tests and simultaneous confidence intervals for inferences concerning symmetry in k × k contingency tables. We propose a modified Wald statistic as a competitor to Bowker's test. We also proffer quadratic estimators of confidence intervals. In large samples, the recommended test statistic rejects the null hypothesis at the stated level of significance when the null hypothesis is true and always rejects with greater power than Bowker's test. The proffered interval estimators provide good simultaneous coverage of the pairwise differences between the po...
Assessing and referring adolescents' health-related social problems: qualitative evaluation of a novel web-based approach.

We conducted a qualitative study to examine users' perceptions of a web-based screening and referral system for young adults with health-related social problems. The first 50 patients who used the ...
An ATP2e− stoichiometry of 112 is thermodynamically possible for Site 3 of oxidative phosphorylation

Abstract Free energy changes for ATP synthesis (ΔGP) and 2e−-transfer across Site 3 (ΔGR) were determined during oxidative phosphorylation by rat liver mitochondria. At static head, −ΔG R ΔG P ranged narrowly between 1.55 and 1.59 with five different respiratory substrates. Thus, an ATP 2e − of 1 1 2 at Site 3 is thermodynamically possible with regards to overall reactants and products. Using nonequilibrium thermodynamics, phenomenological stoichiometries were close to 1 1 2 for all substrates suggesting that ATP 2e − at Site 3 is, in fact, 1 1 2 . An ATP 2e − of 1 1 2 can only be possible if H + O is 4 for cytochrome oxidase.
The depiction of mental illnesses in children's television programs

Concern has been expressed that negative attitudes toward people with mental illnesses begin to develop early in childhood. This study examines one of the possible sources of learning of such negative attitudes—children's television programs. Two hundred sixty-nine (269) hours of children's television programming were videotaped, viewed, and rated. Nearly half the programs viewed contained use of mental health terms. Most of these terms were slang and disrespectful (e.g., crazy and nut) and were used to disparage others. Twenty- one (21) characters with a mental illness were identified. These characters tended to be depicted as aggressive and threatening, and other characters responded to them with fear, exclusion, and disrespect. Children's television programs seem to provide substantial opportunity for children to develop negative attitudes and behaviors toward those with mental illnesses. © 2007 Wiley Periodicals, Inc.