cssi/SciSciGPT-SciSciNet huggingface dataset:
Blood–Brain Barrier Degradation and the Implication of SPARC Protein as a Potential Therapeutic Target for Alzheimer’s Disease

ABSTRACT Alzheimer’s disease is a progressive neurodegenerative disorder affecting a substantial portion of the older population, with the number of afflicted individuals expected to grow with time. Although numerous contributing factors to the disorder have been identified, there is currently no cure or effective prevention method. With the situation as dire as it is, many efforts have been made to shed light on the mechanisms tying diverse contributing factors to the pathogenesis of Alzheimer’s disease. One common neuropathological feature of Alzheimer’s disease is the dysfunction of the blood–brain barrier, which normally maintains brain homeostasis by isolating it from the peripheral circulation and mediating the transport of various bloodborne elements in and out of the brain. An increase in the blood–brain barrier permeability has been observed in Alzheimer’s disease at a level considerably above normal aging. This chapter provides an overview of the effects of aging, the neuroimmune system, inflammation, traumatic brain injury, apolipoprotein E gene e4 allele, and secreted protein acidic and rich in cysteine (SPARC) protein on blood–brain barrier. The potential of SPARC as a therapeutic target for Alzheimer’s disease, and the application of deep-learning-based virtual screening tools against SPARC protein are explored.
The Application of Mastery Criterion to Individual Operants and the Effects on Acquisition and Maintenance of Responses

Instructors assess the acquisition of new skills by delivering blocks of trials containing multiple operants. Mastery is evaluated as percentage correct across all operants in the block. The purpose of the current study was to investigate this traditional mastery criterion arrangement compared to an analysis of mastery at the level of individual operants. In both conditions, mastery criterion was 100% accuracy in one session. In the Set Analysis (SA) condition, accuracy was evaluated as average correct responding across all 4 target operants, or sight words, in a set. In the Operant Analysis (OA) condition, we taught 4 sight words simultaneously, assessed accuracy per sight word, and substituted new sight words into the set each time a single sight word was mastered. Overall, all 4 participants learned textual responses to sight words quicker in the OA condition, the reliability of maintenance was similar across conditions for 2 of 4 participants, and 4 of 4 participants maintained a higher or same number of responses from the OA condition compared to the SA condition. Implications for skill acquisition are discussed.
Multi-object segmentation of anatomical layers in intravascular polarization-sensitive optical coherence tomography using convolutional neural networks

Intravascular polarimetry complements the high-resolution images of conventional intravascular optical coherence tomography (OCT) with quantitative measures of tissue polarization properties that relate to tissue composition. Yet, additional metrics further complicate image interpretation, and leveraging the quantitative polarization metrics currently relies on tedious manual segmentation. Here, we developed a customized convolutional neural network multi-class segmentation model to detect the intima-media boundary whenever visible and otherwise identify the presence of attenuating plaque that masks this boundary. Combined with the IV-OCT backscatter signal, the polarization metrics that enhance the discrimination of targeted features, thereby improving the accuracy and robustness of automated segmentation and lesion identification.
Molecular Design Considerations for Different Classes of Organic Scintillators

The purpose of this chapter is to review the distinguishing characteristics of different classes of organic scintillators with respect to the performance requirements of typical use cases. Discussion of the relevant physical and photophysical parameters will be provided in the context of the rational design of radiation detection materials. A partial list of these properties is as follows: scintillation light yield, emission wavelength and anisotropy, timing characteristics, ionizing particle discrimination, optical attenuation length, mechanical and environmental robustness, detector volume, and cost. Material design considerations relative to these properties are one of the main objectives of this Chapter. Aromatic materials can produce scintillation light in response to ionizing radiation. This characteristic has been observed in crystalline, liquid, and amorphous scintillators, owing to a process that includes ionization recombination, population of excited electronic states, and radiative de-excitation. Organic scintillators from each category are employed today to satisfy the specific requirements of a wide range of applications. The photophysical and scintillation properties of molecules used in organic scintillators vary across a wide range. This has resulted in over 70 years of research aimed at developing scintillators that possess specific physical and scintillation characteristics. In 1956, Sangster and Irvine Jr. published an in-depth survey describing the scintillation properties of more than fifty organic molecular crystals. This work was significant since it described several important considerations that continue to govern contemporary scintillator development efforts: (1) the scintillation efficiency is dependent upon the electronic structure and fluorescence properties of the constituent molecules, (2) the orientation, shape, and steric properties of the molecule impact the mechanisms of energy transfer giving rise to scintillation, (3) the scintillation efficiency is sensitive to defects and the presence of molecular impurities. Later studies also addressed practical considerations such as detector fabrication/scale-up and the relationship between molecular structure and mechanical properties. These categories provide a general framework from which to approach the development of improved organic scintillators.
Protective Behavioral Strategies and Alcohol Use While Pregaming: The Moderating Role of Depression and Anxiety Symptoms.

The study evaluated the moderating role of anxiety and depression symptoms on the association between subscales on the Protective Behavioral Strategies for Pregaming (PBSP) scale (safety and famili...
Double Whammy: A Case of Concurrent Alcohol Use and Hereditary Hemochromatosis Leading to Avascular Necrosis of the Femur

Avascular necrosis (AVN) of the femur is due to damage to the vasculature of the bone and can include a multitude of causes including medications, alcohol intake, hemoglobinopathies, thrombophilias, and connective tissue disorders, among others. Hereditary hemochromatosis is not a common cause of AVN but should be considered prior to labeling such cases as idiopathic. If a patient has symptoms of persistent hip pain and plain radiography has been unremarkable, one should proceed with magnetic resonance imaging (MRI) of the affected joint due to its sensitivity in detecting osteonecrosis. We present a case report of a 54-year-old male patient with a significant history of alcohol intake and a diagnosis of hereditary hemochromatosis who presented with persistent left hip pain and further imaging revealed the presence of osteonecrosis of the femur.
Chapter 4 – Flow Immunosensor

Publisher Summary The flow immunosensor combines the selectivity and sensitivity of traditional immunoassays with a non-equilibrium displacement reaction that allows rapid analysis of small-molecular weight compounds within minutes. In the flow immunosensor, displacement immunoassays are incorporated into a device that is set up under continuous buffer flow. The essential components of the system are immobilized antibodies on a solid-support, antigen analogs that are labeled with a reporter molecule, and the associated hardware needed to establish a controlled flowing system. Flow immunosensors find their application in aviation security, drug detection, and environmental monitoring and field demonstrations. Immunoassays and immunochemical field methods performed in flow provide direct, simple, and rapid detection of analyte, highlighting a unique advantage of the flow immunosensor format. Another advantage of the flow immunosensor is that it is field-portable and can be carried on-site for real-time analysis of the various analytes. Future advances in the flow immunosensor technology will involve improvements in assay components and hardware/software innovations. The ideal flow immunosensor for field use would contain integrated reference/calibration capabilities and could be run for extended periods of unattended use.
Structure of the Catalytic Core of S. cerevisiae DNA Polymerase η: Implications for Translesion DNA Synthesis

DNA polymerase eta is unique among eukaryotic polymerases in its proficient ability to replicate through a variety of distorting DNA lesions. We report here the crystal structure of the catalytic core of S. cerevisiae DNA polymerase eta, determined at 2.25A resolution. The structure reveals a novel polydactyl right hand-shaped molecule with a unique polymerase-associated domain. We identify the catalytic residues and show that the fingers and thumb domains are unusually small and stubby. In particular, the unexpected absence of helices "O" and "O1" in the fingers domain suggests that openness of the active site is the critical feature which enables DNA polymerase eta to replicate through DNA lesions such as a UV-induced cis-syn thymine-thymine dimer.
Characterizing functional connectivity patterns during saliva swallows in different head positions

The anatomical rationale and efficacy of the chin tuck in improving airway protection for some people with swallowing disorders have been well researched and established. However, there are still open questions regarding whether brain activity for swallowing control is altered while performing this chin-tuck maneuver. In this study, we collected EEG signals from 55 healthy adults while swallowing in the neutral and chin-tuck head positions. The time-frequency based synchrony measure was used to form brain networks. We investigated both the small-world properties of these brain networks and differences among the constructed brain networks for the two head positions during swallowing tasks. We showed that brain networks for swallowing in both head positions exhibit small-world properties. Furthermore, we showed that swallowing in the chin-tuck head position affects brain networks in the Alpha and Gamma frequency bands. According to these results, we can tell that the parameter of head position should be considered in future investigations which utilize EEG signals during swallowing activity.
Decision model for selecting a sedan car

There is a large variety of sedan cars available in the market in the US, and deciding on what sedan car suits a person best is difficult. This paper presents a hierarchical decision model (HDM) to help make that decision. HDM has been chosen for this purpose because it allows the users to easily visualize how decision elements at each level of the decision hierarchy impact the final decision. It is also provides information to the manufacturers to determine what characteristics of the car need to be improved. This paper uses the following six selection criteria: fuel economy, overall crash test rating, costs, features, performance, and dependability. Although there are other factors that go into a sedan car, these six are considered the most important criteria for selecting a sedan car. The authors of the paper provided their quantified judgments using pairwise comparisons to demonstrate the model. The use of the HDM with pairwise comparisons resulted in weighted values for each element at each level of the decision hierarchy. The model was applied to the top five best-selling sedans of 2012, and Honda Accord LX 2012 was selected as the best among them.
A unified theory of Stark broadening for hydrogenic ions—III. Results for He II Lyman-alpha

Abstract Calculations have been performed for He II Lyman-α using a previously developed theory (Papers I and II in this series) in which the effect of time-ordering in the required time development operator is retained. Representative results are given for an electron density of 1017 cm-3 and a temperature of 40,000°K. Compared with non-time ordered results, these profiles are about 17% lower at line center and up to 16% higher in the wings. In addition, since the perturbing electron is speeded up by the Coulomb attraction, in comparison with neutral hydrogen the static results are not obtained until much further into the line wings. Comparison is also made to the calculations of Kepple for which good agreement is obtained, except near the line center where the difference approaches 25%.
A convenient synthesis of methylenomycin B. Further mechanistic studies on the SET catalyzed electrocyclization of enynones.

Abstract Methylenomycin B ( 3a ) has been prepared in ∼55% yield by SET catalyzed cyclization of enyone 1a . Mechanistic studies indicate that initial electron donation takes place at C-3 in enolized intermediates of type 2a
The selection and pricing of retail assortments: an empirical approach

Abstract Determining the best assortment to carry is one of the most central problems in retailing. The key decisions are what items to stock and how to price them. In this article, we develop and test an empirical (or nonparametric) approach that simultaneously addresses the selection and pricing problems. The approach is then applied to the problem of selecting an optimal assortment of backpacks from a field of eight available items. The empirical procedure generates data from a calibration sample of shoppers that we use to determine supposedly optimal assortments (of size k = 2, 3, 4, and 5). In a validation analysis on a new sample of shoppers, from the same parent population, it is shown that in this instance the new approach does yield significantly more profitable retail assortments, in all cases (e.g., for all assortment sizes), when compared with more traditional approaches. Additionally, the experimental approach predicts sales and profitability more accurately than traditional approaches.
Functional Constraints of Nuclear-Mitochondrial DNA Interactions in Xenomitochondrial Rodent Cell Lines

The co-evolution of nuclear and mitochondrial genomes in vertebrates led to more than 100 specific interactions that are crucial for an optimized ATP generation. These interactions have been examined by introducing rat mtDNA into mouse cells devoid of mitochondrial DNA (mtDNA). When mtDNA-less cells derived from the common mouse (Mus musculus domesticus) were fused to cytoplasts prepared from Mus musculus, Mus spretus, or rat (Rattus norvegicus), a comparable number of respiring clones could be obtained. Mouse xenomitochondrial cybrids harboring rat mtDNA had a slower growth rate in medium containing galactose as the carbon source, suggesting a defect in oxidative phosphorylation. These clones respired approximately 50% less than the parental mouse cells or xenomitochondrial cybrids harboring Mus spretus mtDNA. The activities of respiratory complexes I and IV were approximately 50% lower, but mitochondrial protein synthesis was unaffected. The defects in complexes I and IV were associated with decreased steady-state levels of respective subunits suggesting problems in assembly. We also showed that the presence of 10% mouse mtDNA co-existing with rat mtDNA was sufficient to restore respiration to normal levels. Our results suggest that evolutionary distance alone is not a precise predictor of nuclear-mitochondrial interactions as previously suggested for primates.
Spinorial representations of SU(3) from a factored harmonic-oscillator equation

We construct a seven-dimensional Dirac equation for quarks by extending the Klein - Gordon equation to seven dimensions, introducing a harmonic-oscillator term in the extra three dimensions, and taking the `square root' of the resulting equation. To facilitate solving the factored equation, we identify an SU(3) algebra in the higher dimensions and use the eigenstates of its Cartan subalgebra as basis functions. We find that the eigenstates of the extended Dirac equation are indeed exact representations of SU(3), one of which we identify with quarks. Indeed, a whole tower of SU(3) Dirac states appears. For principal quantum number , we find a singlet of mass zero; for , we find two 3s of mass , where is an adjustable constant; for , we find two 6s and two 3-bars, all of mass ; etc. Except for the ground state, all SU(3) representations appear in pairs. It is not clear that the pairs can be identified with weak-isospin doublets.
Anatomical considerations of utility curves in Zooarchaeology

Abstract In the past decade many researchers have studied the differential food utility and transport of carcass parts of various animal taxa. Indices of carcass part utility based on those studies have increasingly been used to explain bone frequencies in archaeological sites in terms of human behaviours. Many of the newly developed indices provide potentially flawed measures of human behaviour, however, due to an inverse correlation between the utility of bone parts and the potential for those bone parts to be destroyed by density-mediated attrition. Such correlations probably result from the functional relationship of bone density and associated soft-tissue anatomy. Illusory results will be derived until such time as utility indices are not correlated with preservation potential, or, analytical techniques for differentiating transported and ravaged assemblages that are not dependent solely on bone frequencies are developed.
In situ ellipsometric study of a palladium catalyst during the oxidation of methane

Ellipsometry is used to follow the growth of a PdO layer on the surface of a thick Pd-film catalyst during methane oxidation at ∼ 500°C. The oxide layer that develops under rich conditions (excess CH4) is quite porous and roughens with time. Little CO is formed during this period, but the CO2 formation rate increases until spontaneous oscillations develop, which correlate with changes in the ellipsometric data. These changes indicate that the porous oxide rapidly converts to a metal-rich state, which has decreased catalytic activity, and then slowly reoxidizes.
Quantum phase transitions across a p-wave Feshbach resonance.

We study a single-species polarized Fermi gas tuned across a narrow $p$-wave Feshbach resonance. We show that in the course of a Bose-Einstein condensation (BEC)-BCS crossover, the system can undergo a magnetic-field-tuned quantum phase transition from a ${p}_{x}$-wave to a ${p}_{x}+i{p}_{y}$-wave superfluid. The latter state, that spontaneously breaks time-reversal symmetry, furthermore undergoes a topological ${p}_{x}+i{p}_{y}$ to ${p}_{x}+i{p}_{y}$ transition at zero chemical potential $\ensuremath{\mu}$. In two dimensions, for $\ensuremath{\mu}g0$ it is characterized by a Pfaffian ground state exhibiting topological order and non-Abelian excitations familiar from fractional quantum Hall systems.
Beyond the Canonical 20 Amino Acids: Expanding the Genetic Lexicon

The ability to genetically encode unnatural amino acids beyond the common 20 has allowed unprecedented control over the chemical structures of recombinantly expressed proteins. Orthogonal aminoacyl-tRNA synthetase/tRNA pairs have been used together with nonsense, rare, or 4-bp codons to incorporate >50 unnatural amino acids into proteins in Escherichia coli, Saccharomyces cerevisiae, Pichia pastoris, and mammalian cell lines. This has allowed the expression of proteins containing amino acids with novel side chains, including fluorophores, post-translational modifications, metal ion chelators, photocaged and photocross-linking moieties, uniquely reactive functional groups, and NMR, IR, and x-ray crystallographic probes.
Three dimensional proton exchange membrane fuel cell cathode model using a modified agglomerate approach based on discrete catalyst particles

Abstract The spherical agglomerate model represents the most detailed description of the PEM fuel cell catalyst layer as it accounts for both micro and macroscale transport phenomena. The usual approach with the classical spherical agglomerate model is to couple the homogenous mixture assumption for the agglomerate core to its idealized spherical geometry to obtain an analytical solution which is easily incorporated within a macroscale model. In this study, we incorporate numerical results from a modified agglomerate model based on discrete platinum particles [33] to create a more physically realistic 3D macroscale model for the PEM fuel cell cathode catalyst layer. Results from the 3D cathode model based on the modified particle approach are compared with the classical model and the macro-homogenous model. We find that, similar to the classical approach, the modified 3D model is able to reproduce previously reported trends for reactant, reaction rate, and overpotential distributions, whereas the macro-homogenous model fails to predict mass transport limitations properly. It is also shown that, unlike the classical approach, the modified 3D model is able to accurately predict the effect of Pt loading in the diffusion-loss region.
Extramatrical hyphae as sinks for carbon in ectomycorrhizal pine seedlings

Abstract Allocation of carbon to extramatrical (EM) hyphae has heretofore not been based on accurate estimates of EM hyphal mass. To test the demand of EM hyphae for carbon, pine seedlings that had been inoculated by two different techniques (pouch inoculated, P+, and commercial vermiculite inoculated, V+) were labeled with 14 C in root mycocosms, and the amount and distribution of the label quantified at 4 and 9 days. Carbon use in host, mycorrhizae and EM hyphae depended on spatial and temporal relationships between host and mycobiont. Isotope translocation to seedling components also differed among the inoculation treatments. Based on gravimetric estimates of hyphal mass, more 14 C remained in hyphae from the P+ seedlings than in hyphae from the V+ seedlings after 9 days. Overall, 14 C allocation in V+ seedlings was similar to that in the uninoculated control seedlings. It is hypothesized that EM hyphae of P+ seedlings emanated directly from host roots and may have been more closely linked with the host than were V+ hyphae, allowing P+ hyphae to derive carbon directly from the host, while V+ hyphae existed semi-saprophytically and were less of a sink for carbon.
Predictors of skin self-examination performance.

BACKGROUND Skin self-examination (SSE) may reduce the death rate from melanoma by as much as 63%. Enhancing SSE performance may reduce mortality and morbidity. This study determined predictors of SSE performance in a population of individuals who were at risk of developing melanoma or nonmelanoma skin carcinoma (NMSC). METHODS Patients (n = 200) were asked about their knowledge of the warning signs, their sense of the importance of SSE to them, their attitude about and confidence in their ability to perform SSE, and their impression of their partner's comfort and ability with assisting in the skin examination. The interval since last skin examination, the number of physician visits (nondermatologist and dermatologist), the number and type of skin malignancies, the time since initial diagnosis, the number of skin biopsies, and health insurance status were determined from the medical records for the prior 3 years. RESULTS Seventy percent of participants performed SSE. The three strongest predictors of SSE performance were attitude, having dermatology visits with skin biopsies and at least one skin carcinoma in the previous 3 years, and confidence in performance (P = 0.0001). Other predictors of SSE performance were perceived risk (P = 0.0001), knowledge (P = 0.004), and younger age (P = 0.045). CONCLUSIONS Annual skin examination by physicians and monthly SSE by patients reinforce one another in promoting early detection. In this high-risk population, the dermatologist reinforced SSE performance by biopsy of skin lesions that were skin malignancies. People have intimate knowledge of their own skin and bear the consequences for failure to detect and treat skin carcinoma early; thus, monthly SSE becomes relevant as a personal health-promotion habit. Cancer 2002;95:135–46. © 2002 American Cancer Society. DOI 10.1002/cncr.10637
Dehydration of the residues of the return water of Zaporozhe refractory plant

The residue dehydration process depends upon the properties of the residues and the form of treatment of them. The optimum residue filtration conditions under vacuum are vacuum 0.067 MPa, length of filtration 2 min, and the use of belting fabric. The productivity of the vacuum filter is from 48.8 to 91.8 kg/(m2·h) and the moisture content of the residue is reduced from 82.3–86.5 to 59.3−58.1%.
Ultraviolet B exposure activates Stat3 signaling via phosphorylation at tyrosine705 in skin of SKH1 hairless mouse: A target for the management of skin cancer?

Abstract Understanding the molecular determinants of ultraviolet (UV) response may lead to the development of novel targets; and therefore, better approaches for the management of cancers, which mainly arise due to the exposure of skin to UV (particularly its UVB spectrum). Signal transducer and activator of transcription (Stat) proteins have been shown to activate multiple signaling pathways to contribute to oncogenesis. Here, we studied the regulation of Stat3 during UVB exposure-mediated responses in the skin of SKH-1 hairless mouse, a model regarded to possess relevance to human situations. Our data demonstrated that a single UVB (180 mJ/cm 2 ) exposure to the skin of SKH-1 hairless mice resulted in significant upregulation in (i) protein levels of Stat3 and (ii) phosphorylation of Stat3 at tyrosine 705 . Further, the activation of Stat3 was found to be associated with a decrease in apoptotic response of UVB and a gradual time-dependent increase in leukocyte infiltration and hyperplasia. In conclusion, we have demonstrated, for the first time, that UVB exposure to skin resulted in an activation of pro-survival protein Stat3. Based on our observation, we suggest that Stat3 could serve as a target for the management of UVB exposure-mediated damages including skin cancer.
WOMEN'S EXPERIENCES IN THE STEM COMMUNITY COLLEGE TRANSFER PATHWAY

The experiences of women using the community college transfer pathway to earn four-year degrees in science, technology, engineering, and math (STEM) fields have not been studied extensively. This study examined the experiences of thirty women (67% first-generation college students, 23% ethnic minority students) pursuing STEM degrees; they were interviewed once while finishing at commu nity college and again one semester later. The results illustrate facilitators at the community college, including inspirational professors, effective transfer advising, academic resources, and flexible work schedules, and barriers resulting from ineffective initial advising. After transferring to a four-year institution, the majority of women persisted in STEM majors despite many barriers, such as negative course experiences, poor advising, and limited finances. Finding a helpful professor or advisor and cotransfer support boosted belongingness and contributed to persistence. Two students switched to nonSTEM fields, while two students withdrew from the four-year school completely; these students faced significant financial barriers and did not find a helpful professor or advisor in a STEM field. Finally, four students delayed their transfer, primarily due to financial reasons and family responsibilities. Implications for future research and practice are discussed.
Video cases for teacher learning: issues of social and organizational design for use

This paper provides the foundation for an interactive symposium on the design of web-based systems to support teachers' professional development with videos of exemplary teaching practice. Five existing systems are examined against a common framework examining their design in terms of the models of use that they support.
Characterization of chitin preparations using powder and film X-ray diffraction methods

Chitin is a natural polysaccharide found in many diverse phyla and almost always occurs in association with protein. In this study the chitin polymer is characterized by X-ray diffraction from its naturally occurring unprocessed state through various steps used in the purification procedure. In addition, the effect of different treatments on the final product is examined. These studies show that native chitin has a characteristic diffraction pattern that is not altered by the mild treatments used to isolate relatively pure chitin. Chitins prepared from different sources exhibit the same characteristic diffraction pattern. In addition, chitin films prepared using non-degrading solvents retain most of the characteristic patterns. De-acylation of chitin to produce chitosan results in large changes to the diffraction pattern. To a very limited extent features present in the diffraction pattern of native chitin can be recovered by re-acylation of chitosan.
Neural-network-based target detection system for FLIR imagery

This paper describes a Neural Network based target detection system for Forward-Looking Infrared (FLIR) imagery. We apply a series of four algorithms (detection, two layers of clutter rejection and one of centering) to successively reduce the False Alarm Rate while maintaining a high probability of detection (Pd). The detection stage scans the entire image to find regions approximately the size of a target with pixel statistics that differ from their local background. The clutter rejection stages eliminate portions of these detections, while the centering algorithm moves each detection to the point near it which is most like prior examples of perfectly centered targets. The system was trained and tested on a large set of second generation FLIR data.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Nanoparticle-Enhanced MRI to Evaluate Radiation Delivery to the Regional Lymphatics for Patients With Breast Cancer

Purpose At present, radiation (RT) fields are based largely, and often solely, on bony anatomy. Recent efforts have been taken to better define lymphatic regions for RT planning. Lymphotrophic nanoparticle–enhanced MRI (LN-MRI) allows for accurate identification of malignant and benign lymph nodes. We sought to evaluate RT delivery to lymphatics for breast cancer using LN-MRI. Methods and Materials Twenty-three patients with breast cancer underwent LN-MRI. MRIs were anatomically registered to a reference CT; benign and malignant lymph nodes were contoured. Standard RT fields were planned and dose calculated to prescribe 45–50 Gy. Lymphatic regions were contoured on CT. Coverage of LN-MRI lymph nodes by RT fields and contoured lymphatics were assessed. Results Eighty-one percent of all lymph nodes defined by LN-MRI were covered by the 45-Gy isodose line; 82% of malignant and 79% of benign. The 50-Gy isodose line only encompassed 60% of LN-MRI defined lymph nodes—64% of malignant and 59% of benign. For nodal volumes contoured in the absence of a margin, 86% of actual lymph nodes were within contoured volumes. When a 5-mm expansion was added, 99% were included. Conclusions LN-MRI is a useful tool to delineate the location of breast regional lymphatics. These results suggest less than desired coverage of lymph nodes using standard RT fields and that a margin may be advisable when defining nodal volumes by CT. The use of IMRT and RT in lieu of surgery makes accurate definition of the location of breast regional lymphatics of paramount importance.
Spin Information from Vector-Meson Decay in Photoproduction

For the photoproduction of vector mesons, physically meaningful single and double spin observables are defined in the γN center-of-mass system, which we prefer over extracting density matrix elements in the vector meson rest frame, since angle and energy evolution of spin observables can yield insights into special dynamics. Assuming negligible background amplitudes, we show that: (1) measuring the two pseudoscalar meson decay of a photoproduced ρ or φ does not determine the vector meson’s vector polarization, but only its tensor polarization and (2) vector meson decay into lepton pairs is also insensitive to the vector meson’s vector polarization, unless one measures the spin of one of the leptons. Similar conclusions hold for all double spin observables which involve observation of two-meson vector meson decay. To access the vector meson’s vector polarization, one therefore needs to either measure the spin of the decay leptons, make an analysis of background interference effects or relate the vector meson’s vector polarization to other accessible spin observables.
Mediastinal mass: a mystery of two rounded chambers

A 65-year-old woman with aortic and mitral mechanical prosthetic valves presented with right-sided chest pain. Nine months prior, coronary artery bypass grafting was performed for significant ostial right coronary artery (RCA) and obtuse marginal stenoses. Due to bleeding from the proximal anastomosis of the saphenous vein graft (SVG) to the RCA, urgent sternotomy for repair was required. A subsequent chest radiograph showed a small, rounded structure in the right mediastinum near the aortic arch. On presentation, a chest radiograph showed a nodular opacity in the right anterior mediastinum adjacent …
Cyclic Feature Detection With Sub-Nyquist Sampling for Wideband Spectrum Sensing

For cognitive radio networks, efficient and robust spectrum sensing is a crucial enabling step for dynamic spectrum access. Cognitive radios need to not only rapidly identify spectrum opportunities over very wide bandwidth, but also make reliable decisions in noise-uncertain environments. Cyclic spectrum sensing techniques work well under noise uncertainty, but require high-rate sampling which is very costly in the wideband regime. This paper develops robust and compressive wideband spectrum sensing techniques by exploiting the unique sparsity property of the two-dimensional cyclic spectra of communications signals. To do so, a new compressed sensing framework is proposed for extracting useful second-order statistics of wideband random signals from digital samples taken at sub-Nyquist rates. The time-varying cross-correlation functions of these compressive samples are formulated to reveal the cyclic spectrum, which is then used to simultaneously detect multiple signal sources over the entire wide band. Because the proposed wideband cyclic spectrum estimator utilizes all the cross-correlation terms of compressive samples to extract second-order statistics, it is also able to recover the power spectra of stationary signals as a special case, permitting lossless rate compression even for non-sparse signals. Simulation results demonstrate the robustness of the proposed spectrum sensing algorithms against both sampling rate reduction and noise uncertainty in wireless networks.
Elasticity of nanometer-sized objects

We initiate the development of a theory of the elasticity of nanoscale objects based upon physical concepts which remain properly defined on the nanoscale. This theory provides a powerful way of understanding nanoscale elasticity in terms of local group contributions and gives insight into the breakdown of standard continuum relations. We also give two applications. In the first, we show how to use the theory to derive a relation between the bending and stretching properties of nanomechanical resonators and prove that it is much more accurate than the continuum-based relations currently employed in present experimental analyses. In the second, we link features of the underlining electronic structure to the elastic response of a silicon nanoresonator.
Atherogenic Lipids, Vascular Dysfunction, and Clinical Signs of Ischemic Heart Disease

The report by Tamai and colleagues1 in this issue demonstrates that therapeutic lowering of serum cholesterol, LDL, and oxidized LDL results in improvement in endothelium-dependent dilation in the forearm vasculature of patients with hypercholesterolemia. These observations are novel and particularly interesting because they show that atherogenic lipids can interact with and adversely affect blood vessel function even more rapidly than previously suspected. It is important to consider that past research2 has focused on the effects of serum lipids on atherogenesis over decades. However, more recent trials in patients have shown that treatment of serum lipids can improve clinical outcomes in 18 months to 3 years,3 4 improve endothelial dysfunction in atherosclerotic arteries in 6 to 12 months,5 6 7 and affect endothelium-dependent vasomotor function in the forearm in 2 to 12 weeks.8 The article by Tamai et al1 now shows that the relationship between atherogenic lipids and vascular dysfunction is dynamic and subject to change within minutes. This finding has important implications regarding the pathogenesis of ischemic syndromes and the use of potent and rapidly acting lipid-lowering therapies in patients. Native LDL has little direct effect on essential function(s) in cells within the arterial wall. However, when LDL is metabolized by endothelial cells, the normal component antioxidants (eg, α-tocopherols and β-carotene) are exhausted, the polyunsaturated phospholipids are converted to reactive hydroxyfatty acids, lysophosphotidylcholine is formed, and the proteins in the apolipoprotein-B 100 moiety undergo covalent modification and fragmentation so that the ligand can no longer bind to the classic LDL receptor. Eventually, this “oxidized” LDL molecule becomes more negatively charged, binds to alternative sites (eg, the scavenger receptor), and becomes capable of a wide range of toxic effects, leading to cell/vessel wall dysfunction(s).9 These characteristic cell dysfunctions are consistently associated with the development …
The Experiences of African American Physical Education Teacher Candidates at Secondary Urban Schools.

Presently, most physical education teachers in the United States are White Americans and from middle class families. In fact, 83 % of all teachers in public schools are White Americans, whereas approximately 10 % of all African American teachers are representative of all teachers in the United States. A student might feel cultural dissonance that she or he is behaving appropriately based on the student’s cultural norm and upbringing, but the teachers who have different cultural and ethnic backgrounds than the students may inappropriately interpret or respond to the behavior. Therefore, it is important to study African American pre-service physical education teachers’ student teaching and field-based experiences with ethnically diverse adolescence (e.g., African American students), because they have the potential to develop a positive relationship between school support, teacher support, and academic achievement and influence student learning, motivation, and engagement in physical education. The purpose of this study was to describe and explain the experiences of African American physical education teacher education (PETE) candidates at secondary urban schools. The research design was explanatory multiple-case study situated in activity theory. Participants were seven African American PETE candidates. The qualitative data sources were interviews, weekly journal reflections, and e-portfolios. The results were (a) navigating power relationships between cooperative teachers and students, (b) a ‘shocking’ experience: Feeling under-prepared, and (c) encountered cultural normalcies and stereotypes in teaching physical education. PETE programs must better prepare teacher candidates for working in urban schools with greater cultural competence and higher self-efficacy.
Impact of simulator training on resident cataract surgery.

Background Virtual reality surgery simulation training improves resident performance as measured by the simulator itself and wet-lab performance. This study aims to determine whether virtual surgery simulator training improves actual resident cataract surgery performance.
Social Work Role in Pain Management with Hospice Caregivers: A National Survey

This article reports on an exploratory study of hospice social workers' assessment and collaborative practices related to pain management; especially caregiver concerns about patient pain. A non-randomized national survey indicated that social workers assess the components of pain but are not able to devote as much attention to it as they feel is needed. While most reported assessing patient and family needs, many do not use standardized assessment instruments. These data suggested that while social workers may understand their role in pain management they struggled for the time and tools needed to help address caregiver concerns related to pain management. This study suggests that the development of standardized assessment instruments for hospice social workers would be helpful and points to the value of team training and discussion about ways the social worker can best assist caregivers with pain management issues. Research is needed on social work interventions with caregivers related to pain to establish an evidence base for hospice social work, cement a role identity for social work in pain management, and facilitate increased interdisciplinary collaboration to improve the team response to all aspects of pain.
Community Structure of Macrozooplankton in Trinity and Upper Galveston Bays

Macrozooplankton were sampled bi-weekly from October 1969 through May 1973 at 16 stations. Hydrological measurements, including water temperature and conductivity, accompanied each biological sample. Sampling sites and species were grouped by cluster analysis using Camberra-Metric measure of dissimilarity and flexible sorting. Two major seasons, based on taxon composition and abundance, were identified: A warm season (average water temperature above 22°C) dominated by larval and juvenile crustaceans, and a cool season with an abundance of larval fishes. Sites were more similar to each other within a year than they were between years. Differences between years correlated with variations in salinity and temperature. Community structure indices (Shannon-Weaver diversity, species richness and “evenness”) were applied to the seasonal data. Shannon diversity and “evenness” were positively correlated with each other, but richness values were often negatively correlated with the other two indices.
Characterization of the Active Surface Species Responsible for UV-Induced Desorption of O2 from the Rutile TiO2(110) Surface

We have examined the chemical and photochemical properties of molecular oxygen on the (110) surface of rutile TiO2 at 100 K using electron energy loss spectroscopy (EELS), photon stimulated desorption (PSD), and scanning tunneling microscopy (STM). Oxygen chemisorbs on the TiO2(110) surface at 100 K through charge transfer from surface Ti3+ sites. The charge-transfer process is evident in EELS by a decrease in the intensity of the Ti3+ d-to-d transition at ∼0.9 eV and formation of a new loss at ∼2.8 eV. On the basis of comparisons with the available homogeneous and heterogeneous literature for complexed/adsorbed O2, the species responsible for the 2.8 eV peak can be assigned to a surface peroxo (O22–) state of O2. This species was identified as the active form of adsorbed O2 on TiO2(110) for PSD. The adsorption site of this peroxo species was assigned to that of a regular five-coordinated Ti4+ (Ti5c) site based on comparisons between the UV exposure-dependent behavior of O2 in STM, PSD, and EELS data. Ass...
Oxyhalogenation of glycals for the synthesis of anti-tumor-active 2'-halo daunorubicin analogs.

Abstract Alkoxyhalogenation of l -rhamnal diacetate with daunomycinone and N-iodosuccinimide afforded 37% of 7-O-(3,4-di-O-acetyl-2,6-dideoxy-2-iodo-α- l -mannopyranosyl)daunomycinone (4, NSC 331,962) and 7% of the β- l -gluco analog (NSC 353,457); a similar procedure with l -fucal diacetate gave 77% of 7-O-(3,4-di-O-acetyl-2,6-dideoxy-2-iodo-α- l -talopyranosyl)daunomycinone (NSC 327,472). Compound 4 showed high activity (T/C 247) and low toxicity in the P-388 lymphocytic leukemia screen in mice.
Differential Tyrosine Phosphorylation of Plasma Membrane Ca2+-ATPase and Regulation of Calcium Pump Activity by Carbachol and Bradykinin

We investigated the effects of thapsigargin (TG), bradykinin (BK), and carbachol (CCh) on Ca2+ entry via endogenous channels in human embryonic kidney BKR21 cells. After depletion of Ca2+ stores by either TG, BK, or CCh, the addition of Ca2+ gave a much larger rise in Ca2+ levels in CCh-treated and TG-treated cells than in cells treated with BK. However, in experiments performed with Ba2+, a cation not pumped by Ca2+-ATPases, only a modest difference between CCh- and BK-stimulated Ba2+entry levels was observed, suggesting that the large difference in the Ca2+ response is mediated by a differential regulation of Ca2+ pump activity by CCh and BK. This hypothesis is supported by the finding that when Ca2+ is removed during the stable, CCh-induced Ca2+ plateau phase, the decline of cytosolic Ca2+ is much faster in the absence of CCh than in its presence. In addition, if Ca2+ is released from a caged Ca2+ compound after a UV pulse, the resulting Ca2+ peak is much larger in the presence of CCh than in its absence. Thus, the large increase in Ca2+ levels observed with CCh results from both the activation of Ca2+ entry pathways and the inhibition of Ca2+ pump activity. In contrast, BK has the opposite effect on Ca2+ pump activity. If Ca2+ is released from a caged Ca2+ compound, the resulting Ca2+ peak is much smaller in the presence of BK than in its absence. An investigation of tyrosine phosphorylation levels of the plasma membrane Ca2+-ATPase (PMCA) demonstrated that CCh stimulates an increase in tyrosine phosphorylation levels, which has been reported to inhibit Ca2+ pump activity, whereas in contrast, BK stimulates a reduction of PMCA tyrosine phosphorylation levels. Thus, BK and CCh have a differential effect both on Ca2+ pump activity and on tyrosine phosphorylation levels of the PMCA.
Gravitational clumping and the annihilation of monopoles

It is shown that within the standard model of the early universe no consistent scenario can be constructed for sufficient annihilation of monopole-antimonopole pairs due to gravitational clumping. This result implies that the resolution of the problem of too many primordial monopoles must be a mechanism to suppress their initial creation.
Comparative genomic hybridization of esophageal and gastroesophageal adenocarcinomas shows consensus areas of DNA gain and loss

Relatively little is known about the genetic changes that occur in esophageal and gastroesophageal adenocarcinomas. To provide a survey of relative DNA gains and losses in these cancers, we microdissected 15 primary human esophageal and gastroesophageal adenocarcinomas to enrich for cancer cells and subsequently performed comparative genomic hybridization. Eighteen regions of high-level amplification were detected in 11 tumors, with 8p23, 17q21, and 18p11 showing four, three, and two such events, respectively. The most common minimal regions of gain were 8q24 (8/15), 20q (7/15), 17q21 (7/15), and 7p 1-15 (7/15 ). The most common minimal regions of loss were 5q 12-21 (8/15), 4q10-24 (5/15), 4p (5/15), and 18q (3/15). These results implicate the well-characterized oncogenes MYC (8q24) and ERBB2 (17q21), and they predict the involvement of additional oncogenes on 8p23, 20q, and chromosome 7 in the pathogenesis of these cancers. Chromosomes 4 and 5 are frequent targets of deletion in these tumors and may harbor novel tumor suppressor genes.