cssi/SciSciGPT-SciSciNet huggingface dataset:
Analysis and prediction of tilt rotor hover noise

This paper presents new and improved tilt rotor hover noise prediction methods. Calculations include both discrete frequency harmonic noise and broadband noise mechanisms due to the ground plane/fountain recirculating flow. The noise mechanisms studied are thickness, loading, and inflow turbulence noise. In each case aeroacoustic models are developed and compared to noise measurements obtained experimentally for the XV-15 experimental tilt rotor aircraft. Both the effects of the mean and the turbulent fountain flows are found to be important noise sources and have strongly directional radiation patterns toward the rear of the aircraft (the direction of the rotor motion through the fountain flow). Calculations also show that the noise generated by the inflow of ambient atmospheric turbulence can also be an important noise source in hover in some directions. Further development of the methods and models, and precise information about the fountain flow, are needed to improve the predictions and to initiate noise minimization studies.
Design and control of a simplified Stewart platform for endoscopy

Presents the development of a workspace controller for a newly designed platform. The platform is designed to manipulate endoscopic tools and is actuated by tendons to meet the small scale requirements in endoscopy. The tendon actuation provides challenges to the controller design since the number of degrees of freedom equals the number of tendons. In typical tendon-driven systems, the number of tendons is greater than the number of degrees of freedom. This paper presents the kinematic and dynamic analysis of the manipulator and presents a workspace controller for the tendon driven system. Simulation as well as experimental results are presented for the controlled system. The results demonstrate the effectiveness of the controller in tracking a step response and a circular trajectory at 2.0 Hz and greater. The device is similar to the Stewart platform and the basic design can be used in applications where the fall range of motion of the Stewart platform is not required. Applications of the device range between targeting systems, snake-like robots, and endoscopy. >
Fibrosing mediastinitis causing ostial coronary artery compression in a young woman.

![Figure][1] [![Graphic][3] ][3][![Graphic][4] ][4] A 42-year-old woman presented with worsening angina. Electrocardiography showed ST-segment elevation in lead aVR. Coronary angiography showed 80% ostial left main coronary stenosis ( A , [Online Video 1][4]) and 90% ostial right
Quadratic problems defined on a convex hull of points

In this paper we consider an algorithm for a class of quadratic problems defined on a polytope which is described as the convex hull of a set of points. The algorithm is based on simplex partitions using convex underestimating functions.
The Law and Labor Strife in the United States, 1881–1894

This article examines the effects of state-level legal innovations governing labor disputes in the late 1 800s. This was a period of legal ferment in which worker organizations and employers actively lobbied state governments for changes in the rules governing labordisputes. Cross-state heterogeneity inthe legal environment provides an unusual opportunity to investigate the effects of these laws. We use a unique data set with information on 12,965 strikes to show that most of these law changes had surprisingly little effect on strike incidence or outcomes. Important exceptions were maximum hours laws and the use of injunctions. Evaluating the role of the legal envlronment in shaping economic outcomes is often difficult, because of either the lack of microlevel data or the absence of sufficient heterogeneity in laws across jurisdictions. These problems are most severe in recent data, because confidentiality rules limit the availability of data and the imposition of federal law standardizes the legal environment across states. Studies using historical data have overcome these difficulties in examinations of the impact of maximum hours laws, compulsory school attendance laws, banking regulations, mortgage foreclosure moratoria, and regulation of natural resources.' Surprisingly, the same historical approach has not been applied to one of the most contentious areas of legislative intervention in the economy: the regulation of disputes between workers and employers. In this article, we
Constructing courts after communism: Reevaluating the effect of electoral uncertainty

Abstract A prominent view in political science is that electoral uncertainty leads institutional designers to prefer independent and powerful courts. Yet few scholars have examined the design of constitutional courts systematically across Eastern Europe and those who have employed the results of elections held after constitutions were adopted to estimate the actors' perceptions of the balance of power prior to the court's design. This work reevaluates the effects of electoral uncertainty in post-communist Europe using more appropriate data and fuzzy-set qualitative comparative analysis to outline the different causal configurations linking electoral uncertainty to the initial judicial empowerment.
Sequential decision making in two-dimensional hypothesis testing

In this work, we consider the problem of sequential decision making on the state of a two-sensor system with correlated noise. Each of the sensors is either receiving or not receiving a signal obstructed by noise, which gives rise to four possibilities: (noise, noise), (signal, noise), (noise, signal), (signal, signal). We set up the problem as a min-max optimization in which we devise a decision rule that minimizes the length of continuous observation time required to make a decision about the state of the system subject to error probabilities. We first assume that the noise in the two sources of observations is uncorrelated, and propose running in parallel two sequential probability ratio tests, each involving two thresholds. We compute these thresholds in terms of the error probabilities of the system. We demonstrate asymptotic optimality of the proposed rule as the error probabilities decrease without bound. We then analyze the performance of the proposed rule in the presence of correlation and discuss the degenerate cases of perfect positive or negative correlation. Finally, we purport the benefits of our proposed rule in a decentralized sensor system versus one in constant communication with a fusion center.
The trauma spectrum: The interaction of biological and social events in the genesis of the trauma response

When Kardiner first described the full syndrome of what is now called PTSD in 1941, he called the trauma response a “physioneurosis,” that is, a mental disorder which affects both the soma and the psyche. Now, more than 40 years later much knowledge has been gained about the biological effects of traumatization. Based on the studies of disruptions of attachment bonds in non-human primates, the animal model of inescapable shock, and numerous studies of traumatized children and adults, we are beginning to understand the nature of the biological changes which underlie the psychological response to trauma. This paper will explore (1) the nature of the biological alterations in response to traumatization, (2) how these biological shifts depend on the maturation of the central nervous system (CNS), cognitive processes, and the social matrix in which they occur, (3) and how these alterations can influence psychopathological and interpersonal processes.
Selenium effects on antennal integrity and chronic copper toxicity in Daphnia pulex (deGeer).

Although it is obviously important in aquatic toxicological research to maintain experimental animals in chemically defined test media which are both physiologically compatible to the experimental organism and similar to natural waters, such media have not yet been developed for daphnids. Currently, the author has been using reconstituted waters containing only four or five salts in chronic copper toxicity tests with D. pulex. Antennal damage has been rare among control animals and has occurred only in the softest of the waters. However, animals develop antennal damage at an age of about 25 days when exposed to copper concentrations sufficiently high to reduce longevity in soft water. It has recently been shown that such antennal damage in D. pulex may be caused by a selenium deficiency. The objective of the present research was to determine the effect of sodium selenite on the incidence of antennal damage in cohorts of D. pulex exposed to Cu in a soft, reconstituted water.
Combining damage detection methods to improve probability of detection

The objective of this work is to improve the probability of detecting damage and reduce the probability of false positives by combining damage detection methods. Most vibration-based NDD methods are derived from expressions relating the modal properties (i.e., mode shapes and frequencies) and/or the physical properties (i.e., stiffness or flexibility) of an undamaged structure to the modal properties of a damaged structure. These methods utilize some form of a damage indicator to identify the existence and location of damage in a structure. The basic assumption is that the modal and physical properties of the undamaged and damaged structure will differ. Thus, by measuring and comparing the modal properties of the damaged and undamaged structure one can infer whether or not damage exists and in some cases the location of the damage. In this work, we present a methodology to combine the results of the different NDD methods using the techniques of pattern recognition. To accomplish this task, we begin with a review of pattern recognition. Next, we develop a methodology to combine the results of the different NDD methods. To investigate the applicability of the combined approach we perform damage detection on a beam using two damage detection methods (Damage Index Method and a method that utilizes the parameters of an ARMA model as damage indicators) separately and then combined using the developed methodology. Finally, a comparison of the probability of detection and the probability of a false positive is made between the combined approach and the NDD methods applied separately.
Molecular cloning of androgen receptors from divergent species with a polymerase chain reaction technique: Complete cDNA sequence of the mouse androgen receptor and isolation of androgen recepter cDNA probes from dog, guinea pig and clawed frog

Abstract We have cloned and sequenced 2.8 kilobases of cDNA encoding the mouse androgen receptor by RNA amplification with transcript sequencing. Sequence analysis predicts that this cDNA contains an open reading frame of 2697 nucleotides encoding a polypeptide of 899 amino acids. Androgen receptor cDNA probes of dog, guinea pig, and frog were also isolated and sequenced using consensus primers derived from human and rat androgen receptor cDNA s. Northern blot analysis with the species-specific probes revealed similarities in size between amphibian and mammalian mRNAs. These results demonstrate the utility of this technique in obtaining nucleic acid probes and sequence information of steroid receptors from different species. The sequence data and the Northern blot analysis of the receptors in different species demonstrate that the androgen receptor has been well-conserved during evolution.
Bound state spectrum from the light-cone two-body equation in φ3-theories

Abstract The relativistic bound state problem with the light-cone two-body equation (i.e. Bethe-Salpeter equation in the infinite momentum frame) is investigated in the light-cone ladder approximation to φ 3 -theories. A variational principle is found for the eigenvalues. Numerical results are compared with some existing calculations and with some new analytic results.
Cloning and characterization of a mouse brain calcitonin receptor complementary deoxyribonucleic acid and mapping of the calcitonin receptor gene.

We have identified and characterized a mouse brain calcitonin receptor (CTR) complementary DNA (cDNA). This cDNA encodes a receptor protein that, after expression, has high affinity binding for salmon calcitonin (Kd approximately, 12.5 nM) and is coupled to adenylate cyclase. The binding affinity of this expressed receptor for salmon calcitonin is lower than that described for the previously cloned porcine renal and human ovarian CTRs, but is similar to that of the recently described rat brain CTR, designated the C1b form of the receptor. Analysis of the deduced structure of the mouse brain CTR reveals that it is highly related to the other CTR cDNAs that belong to a distinct family of G-protein-coupled receptors with seven transmembrane-spanning domains. The major structural feature that distinguishes the mouse cDNA clone from the other CTRs is the presence of a consecutive 111-basepair nucleotide sequence that encodes a 37-amino acid sequence which is predicted to localize to the first extracellular loo...
Iron-sulfur clusters: Formation, perturbation, and physiological functions

Abstract Iron-sulfur proteins occur in all life forms. Ferredoxins and Rieske proteins each contain a (2Fe2S) cluster whereas photosystem I (PSI) contains three (4Fe4S) clusters. Essential enzymes such as sulfite reductase, nitrite reductase, nitrogenase, glutamate synthase, aconitase, succinate dehydrogenase, ferredoxin/thioredoxin reductase, as well as many other vital proteins, each contain a (4Fe4S) cluster. Iron-sulfur clusters are formed enzymatically from cysteinyl-sulfur and ferritin-sequestered iron. Many iron-sulfur clusters are inactivated by O 2 and/or reactive oxygen species (ROS) such as O 2 •− . Perhaps 0.1 % of the electrons passing through either the mitochondrial electron transport chain or PSI result in the formation of O 2 •− . Many plant stresses increase ROS formation, which subsequently may perturb iron-sulfur clusters. Plants have evolved three different superoxide dismutases (SODs) to control the internal concentrations of harmful ROS. Possible roles of functional and non-functional iron-sulfur clusters in the coordination of metabolic activities of stressed and non-stressed plants are discussed.
Ultrastructural changes during spherule formation in Physarum polycephalum.

Plasmodia of Physarum polycephalum form spherules (microsclerotia) when placed on a nonnutrient salt solution. This investigation was concerned with the ultrastructural changes associated with this type of differentiation. Glycogen granules decreased during the early period of development, and this was confirmed by biochemical techniques. A Golgi complex was noted after 18 hours of starvation; it may be associated with the elaboration of polysaccharides. Evidence was presented which confirmed that cytokinesis occurred by the fusion of vesicles after 24 hours of starvation. Following cleavage, smooth endoplasmic reticulum was observed; it changed to the rough state as spherulation continued. Experiments with cycloheximide suggest that protein(s) necessary for cleavage are synthesized about 20–21 hours after initiation of starvation. Since actinomycin D was found to have no effect on cleavage or wall formation, it appears that new RNA synthesis is not necessary for spherulation.
Medium effects and the shear viscosity of the dilute Fermi gas away from the conformal limit

We study the shear viscosity of a dilute Fermi gas as a function of the scattering length in the vicinity of the unitarity limit. The calculation is based on kinetic theory, which provides a systematic approach to transport properties in the limit in which the fugacity $z=n{\ensuremath{\lambda}}^{3}/2$ is small. Here, $n$ is the density of the gas and $\ensuremath{\lambda}$ is the thermal wavelength of the fermions. At leading order in the fugacity expansion, the shear viscosity is independent of density, and the minimum shear viscosity is achieved at unitarity. At the next order, medium effects modify the scattering amplitude as well as the quasiparticle energy and velocity. We show that these effects shift the minimum of the shear viscosity to the Bose-Einstein condensation side of the resonance, in agreement with the result of recent experiments.
Ferromagnetism in one dimensional systems: synthesis and structural characterization (invited)

Synthetic strategies for designing new 1d magnetic systems are presented. A review is given of some of the structural characteristics which lead to ferromagnetic interactions between metal ions. Results of application of these concepts to the preparation of new quantum 1d systems with ferromagnetic coupling are presented. Special emphasis is given to recent discoveries of spin 1/2 copper (II) salts which have large intrachain coupling.
The Relationship Between the Size of Spatial Subsets of GER 63 Channel Scanner Data and the Quality of the Internal Average Relative Reflectance (IARR) Atmospheric Correction Technique

Abstract This study examined spatial subsets derived from one flightline of Geophysical Environmental Research (GER) 63 channel scanner data from Makhtesh Ramon, Israel, to determine the relationship between the size of spatial subsets and the quality of the Internal Average Relative Reflectance (IARR) atmospheric correction technique. The IARR procedure was run separately on spatial subsets containing 100, 53, 24, 9, 3, 0·16 and 0·02 per cent of the original data set. The correction quality was determined by comparing the reflectance spectra derived from each subset for a site containing the mineral kaolinite. Signal-to-noise ratio (SNR) calculations illustrate that the raw data quality does not vary significantly from one subset to another. The quality of the correction was affected only by changes in the ‘average reference spectrum’ (ARS) associated with the selected subsets. The short-wave infrared (SWIR) region (1·440−2·443 μm) was found to be less sensitive to ARS changes than the visible (VIS) regi...
Anatomical study of the superficial temporal artery.

Fifty consecutive human autopsy specimens were studied to determine the suitability of the superficial temporal artery (STA) for use in microvascular anastomoses. Ten variations of the STA were found. The STA at the zygoma averaged 2.2 mm in outside diameter. The STA averaged 31.7 mm from the zygoma to its bifurcation, where the average outside diameter was 1.9 mm. Eight per cent of the specimens had no bifurcation, and 92% had at least one branch in a frontal or parietal distribution that was greater than or equal to 1 mm. A suitable frontal branch (i.e., greater than or equal to 1 mm in diameter and greater than or equal to 70 mm in length) was found in 90% of the specimens, and a suitable parietal branch was found in 71%. Six specimens (12%) had an additional branch, all of which were of suitable length and diameter. Eight per cent of the specimens lacked a vessel suitable for microvascular anastomosis.
Comparison if Monitoring and Mnemonic Text-Processing Strategies in Learning Disabled Students:

Thirty learning disabled students were given several reading passages for which they first had to identify and then remember the main ideas. Students were randomly assigned in equal numbers to thre...
Differential coupled mode analysis and the Poincare sphere.

The use of Poincare sphere visualization of two-coupled-mode problems is reviewed, and a new vector form of the usual integrated optics differential equations is presented. Unlike previous similar treatments involving propagation over discrete uniform intervals, we show the relationship of the differential form of the coupled mode equations to the Stokes-Mueller formalism, using the Feynman-Vernon-Hellwarth method for the two-level Schrodinger equation. A specific example is given for the tuned fiber coil optical isolator, for which the present method allows a solution by inspection.
Identification of novel genomic regions associated with resistance to Pyrenophora tritici - repentis races 1 and 5 in spring wheat landraces using association analysis

Tan spot, caused by Pyrenophora tritici-repentis, is a major foliar disease of wheat worldwide. Host plant resistance is the best strategy to manage this disease. Traditionally, bi-parental mapping populations have been used to identify and map quantitative trait loci (QTL) affecting tan spot resistance in wheat. The association mapping (AM) could be an alternative approach to identify QTL based on linkage disequilibrium (LD) within a diverse germplasm set. In this study, we assessed resistance to P. tritici-repentis races 1 and 5 in 567 spring wheat landraces from the USDA-ARS National Small Grains Collection (NSGC). Using 832 diversity array technology (DArT) markers, QTL for resistance to P. tritici-repentis races 1 and 5 were identified. A linear model with principal components suggests that at least seven and three DArT markers were significantly associated with resistance to P. tritici-repentis races 1 and 5, respectively. The DArT markers associated with resistance to race 1 were detected on chromosomes 1D, 2A, 2B, 2D, 4A, 5B, and 7D and explained 1.3–3.1% of the phenotypic variance, while markers associated with resistance to race 5 were distributed on 2D, 6A and 7D, and explained 2.2–5.9% of the phenotypic variance. Some of the genomic regions identified in this study correspond to previously identified loci responsible for resistance to P. tritici-repentis, offering validation for our AM approach. Other regions identified were novel and could possess genes useful for resistance breeding. Some DArT markers associated with resistance to race 1 also were localized in the same regions of wheat chromosomes where QTL for resistance to yellow rust, leaf rust and powdery mildew, have been mapped previously. This study demonstrates that AM can be a useful approach to identify and map novel genomic regions involved in resistance to P. tritici-repentis.
Studies on the regio- and diastereo-selective epoxidation of daphnanes and tiglianes

Daphnanes and tiglianes are diterpenes with a shared tricyclic 5-7-6 ring system. Many members exhibit significant biological activities often associated with protein kinase C signaling. Many of these natural products (~100) have a C6-C7 α-epoxide whose influence on biological activity is little studied. Using the more readily available phorbol ester PDBu as a test substrate, we report an efficient, and potentially general, α-epoxidation method based on a vanadium-catalyzed asymmetric epoxidation with bishydroxamic acid (BHA) ligands.
Graminoid community composition and structure within four everglades management areas

Estimates of species density, percentage vegetative cover, biomass, and sawgrass (Cladium jamaicense) height were made in Tall Sawgrass, Medium Sawgrass, and Wet Prairie communities in the SE portion of Water Conservation Area 3A (3A), the SW portion of Water Conservation Area 3B (3B), the NW portion of Northeast Shark Slough (NSS), and the NE portion of Everglades National Park (ENP) during dry season and wet season sampling periods in 1986 and 1987. We summarized the history of water management and hydroperiod manipulation in the study area. Wet Prairie had the deepest water of the three plant communities studied, while 3A had deepest water and longest hydroperiod of the four areas. Generally, the greatest species density occurred in NSS, where water was shallowest. Individual sawgrass plants and their basal tussocks were taller in 3A than in the other three areas, which may make plants in 3A more susceptible to damage by airboats and fire. Cover and biomass of sawgrass fluctuated more between sampling periods than among management areas, which rendered lower measurements in Tall Sawgrass in 3B non-significant. Species composition of Wet Prairies, particularly in 3A whereRhynchospora spp. were absent, andNymphaea odorata was dominant, resembled aquatic sloughs. The low species density in the study area may be related to rapid fluctuations in water levels that could drown slow-growing plants, and to infrequent dry periods that preclude seed germination. Species richness was low, compared with other Everglades plant community studies. No annual emergent plants were encountered.
Low noise voltage and charge preamplifiers for phonon and ionization detectors at very low temperature

Abstract We have developed voltage and charge sensitive FET preamplifiers which feature ultra low noise, convenience and flexibility for phonon and ionization detectors operated at 20 mK. With an NJ132L J-FET, the white noise of the voltage amplifier is 1.1 nV/√Hz at room temperature and 0.9 nV/√Hz when the FET is cooled to ≈120 K; the 1 f knee is below 100 Hz. The power dissipation of the FET, about 7 mW in our application, allows it to be used in a 4 K environment. With the same cooled FET, the charge amplifier has shown a noise of 120 e− rms with a total input capacitance of 45 pF.
An integrated magnetic spectrometer for multiplexed biosensing

There is high demand for at-home and point-of-care medical diagnostic tools as a step toward fast, low-cost, personal medicine. Integrated biosensors based on magnetic labeling schemes offer higher sensitivity and lower cost due to the elimination of the optics and have emerged as a viable alternative to assays that use fluorescence for biomolecular detection. For instance, the frequency-shift sensor of [1] demonstrates a high-sensitivity example of a cost-effective magnetic particle biosensor in CMOS with no need for external magnets. Despite their cost and sensitivity advantages, magnetic biosensors reported so far suffer from a lack of multi-probe diagnostics similar to fluorescent-based approaches that use multiple colors for simultaneous single-site multiple target differentiation. This is primarily because current approaches measure changes in the magnetic susceptibility, χ, either at low frequencies [2,3] or at a fixed RF frequency [1]. Consequently, these approaches do not provide a clear path for differentiating between a large number of small magnetic particles vs. a smaller number of larger size particles with similar magnetic content.
CFTR-SLC26 transporter interactions in epithelia.

Transport mechanisms that mediate the movements of anions must be coordinated tightly in order to respond appropriately to physiological stimuli. This process is of paramount importance in the function of diverse epithelial tissues of the body, such as, for example, the exocrine pancreatic duct and the airway epithelia. Disruption of any of the finely tuned components underlying the transport of anions such as Cl−, HCO3−, SCN−, and I− may contribute to a plethora of disease conditions. In many anion-secreting epithelia, the interactions between the cystic fibrosis transmembrane conductance regulator (CFTR) and solute carrier family 26 (SLC26) transporters determine the final exit of anions across the apical membrane and into the luminal compartment. The molecular identification of CFTR and many SLC26 members has enabled the acquisition of progressively more detailed structural information about these transport molecules. Studies employing a vast array of increasingly sophisticated approaches have culminated in a current working model which places these key players within an interactive complex, thereby setting the stage for future work.
A high performance redundancy scheme for cluster file systems

A known issue in the design of striped file systems is their vulnerability to disk failures. In this paper we address the challenges of augmenting an existing striped file system with traditional RAID redundancy, and proposed a novel redundancy scheme designed to maximize disk throughput seen by applications. We implement our new scheme in CSAR, a proof-of-concept redundant file system based on PVFS, along with two other well known schemes. Our tests using both microbenchmarks and representative scientific applications show that our scheme consistently performs as well as the best of the other two schemes. The application-dependent, potentially larger storage occupation of our scheme is justified by current technological trends that put I/O bandwidth at a premium over disk space.
The Misfiring of German Cultural Leadership in the Twelfth Century: The Evidence from the Cathedral Schools.

Although German culture, Eke German political authority, stood above the rest of Latin Christendom in the late tenth and early eleventh centuries, this cultural pre-eminence was lost during the course of the twelfth century. Nowhere is this more evident than in the German schools. Between 1050 and 1125, a shift occurred, characterized by the desire of aspirants for high ecclesiastical office in Germany going beyond its borders for advanced training. My paper focuses on some of the causes and effects of this shift, on the subsequent decline in German cathedral schoob, and on the retarded entry of Germany into the community of nations which sported universities. It contrasb the challenging (and exciting) curriculum which was developing in the schoob of northern France and northern Italy in the twelfth century with the more conservative (even remedial) curriculum which seemed to become the chief offering of contemporaneous German schoob. The net result of this loss of cultural leadership was that Germany moved to the periphery of cultural activities until the Reformation: leadership passed to France, Italy and even England for the time being.
Adaptive optimisation of noisy black-box functions inherent in microscopic models

For systems where exact constitutive relations are unknown, a microscopic level description can be alternatively used. As microscopic simulations are computationally expensive, there is a need for the development of robust algorithms in order to efficiently optimise such systems taking into consideration the inherent noise associated with the microscopic description. Three optimisation strategies are proposed and tested using a stochastic reaction system as a case study. The first method generates optimal difference intervals to formulate and solve a non-linear program (NLP), whereas the other methods build response surface models and optimise using either a direct search algorithm changing to a steepest descent method once the optimum region is located, or sequential quadratic programming (SQP). The performance of these methods is compared to that of a steepest descent optimisation method commonly used for response surfaces. Their effectiveness is evaluated in terms of the number of microscale function calls and computational time.
Autoimmune Glomerulonephritis Induced in Sheep by Injections ofHuman Lung and Freund's Adjuvant

Sheep immunized with human lung and Freund's adjuvant develop progressive glomerulonephritis with deposition of autoantibodies and complement in the glomerular basement membrane. This nephritis appears to be the first autoimmune disease induced by antigens that are not organspecific. By clinical and immunopathologic criteria, this nephritis appears identical to the nephritis induced in sheep by human glomerular basement membrane and greatly resembles certain nephritides of man, in particular, the nephritis in Goodpasture's disease.
Parallel Multi-Color Fluorescence Lifetime Tomography in Deep Tissue

We present a deep tissue multi-color fluorescence lifetime imaging method based on scanning laser optical tomography and Fourier fluorescence lifetime excitation-emission matrix spectroscopy. We demonstrate FRET sensor measurements in live transgenic zebrafish embryo.
A novel system to accelerate the progression of nerve degeneration in transgenic mouse models of neuropathies

Axon degeneration is a common hallmark of many neurodegenerative diseases. There is now an abundance of spontaneous and genetically engineered mice available to study the mechanisms of axonal degeneration and to screen for axonal protective agents. However, many of these mouse models exhibit slow progressive axonal loss which can span over many months. Consequently, there is a pressing need to accelerate the pace of axonal loss over a short interval for high-throughput screening of pharmacological and genetic therapies. Here, we present a novel technique using acrylamide, an axonal neurotoxin, to provoke rapid axonal degeneration in murine models of neuropathies. The progressive axonal loss which typically occurs over 8 months was reproduced within 7 to 10 days of the acrylamide intoxication. This approach was successfully applied to Myelin Associated Glycoprotein knockout (MAG-/-) mouse and Trembler-J mouse, a popular murine model of Charcot-Marie-Tooth disease type 1 (CMT-1). Acrylamide intoxication in transgenic mouse models offers a novel experimental approach to accelerate the rate of axonal loss over short intervals for timely in vivo studies of nerve degeneration. This report also provides for the first time an animal model for medication or toxin-induced exacerbation of pre-existing neuropathies, a phenomenon widely reported in patients with neuropathies.
The role of Sis1 in the maintenance of the [ RNQ + ] prion

Yeast prions are inherited through proteins that exist in alternate, self-perpetuating conformational states. The mechanisms by which these states arise and are maintained are still poorly defined. Here we demonstrate for the first time that Sis1, a member of the Hsp40 chaperone family, plays a critical role in the maintenance of a prion. The prion [RNQ+] is formed by Rnq1, which is present in the same physical complex as Sis1, but only when Rnq1 is in the prion state. The G/F domain of Sis1 is dispensable for rapid growth on rich medium, but is required for [RNQ+] maintenance, distinguishing essential regions of Sis1 from those needed for prion interaction. A specific Sis1 deletion mutant altered the physical aggregation pattern of Rnq1 without curing the prion. This variant state propagated in a heritable fashion after wild-type Sis1 function was restored, indicating that multiple physical states are compatible with prion maintenance and that changes in chaperone activity can create prion variants. Using a prion chimera we demonstrate that the prion-determinant domain of Rnq1 is genetically sufficient for control by Sis1.
Targeting transporters: Promoting blood–brain barrier repair in response to oxidative stress injury

The blood-brain barrier (BBB) is a physical and biochemical barrier that precisely regulates the ability of endogenous and exogenous substances to accumulate within brain tissue. It possesses structural and biochemical features (i.e., tight junction and adherens junction protein complexes, influx and efflux transporters) that work in concert to control solute permeation. Oxidative stress, a critical component of several diseases including cerebral hypoxia/ischemia and peripheral inflammatory pain, can cause considerable injury to the BBB and lead to significant CNS pathology. This suggests a critical need for novel therapeutic approaches that can protect the BBB in diseases with an oxidative stress component. Recent studies have identified molecular targets (i.e., putative membrane transporters, intracellular signaling systems) that can be exploited for optimization of endothelial drug delivery or for control of transport of endogenous substrates such as the antioxidant glutathione (GSH). In particular, targeting transporters offers a unique approach to protect BBB integrity by promoting repair of cell-cell interactions at the level of the brain microvascular endothelium. This review summarizes current knowledge in this area and emphasizes those targets that present considerable opportunity for providing BBB protection and/or promoting BBB repair in the setting of oxidative stress. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.
The effects of wildfire and environmental amenities on property values in northwest Montana, USA

Abstract This study employed the hedonic price framework to examine the effects of 256 wildfires and environmental amenities on home values in northwest Montana between June 1996 and January 2007. The study revealed environmental amenities, including proximity to lakes, national forests, Glacier National Park and golf courses, have large positive effects on property values in northwest Montana. However, proximity to and view of wildfire burned areas has had large and persistent negative effects on home values. The analysis supports an argument that homebuyers may correlate proximity to and view of a wildfire burned area with increased wildfire risk. Indeed, when a burned area is not visible from a home, wildfire risk appears to be out of sight and out of mind for homebuyers. Findings from this research can be used to inform debate about efficient allocation of resources to wildfire preparedness, including public education programs, and suppression activities around the wildland–urban interface.
Evaluation of hilar biliary strictures by using a newly developed forward-viewing therapeutic echoendoscope: preliminary results of an ongoing experience

Background Obtaining a definitive tissue diagnosis in patients with hilar biliary strictures (HBS) is often difficult. Objective To describe our experience using a newly developed forward-viewing linear echoendoscope (FVL-EUS) with FNA as a primary diagnostic tool in patients with HBS. Design Case series. Setting A tertiary care, academic medical center. Patients Four patients with HBS who underwent the procedure. Main Outcome Measurements Performance of FNA with the FVL-EUS. Results Visualization and puncture of the primary lesion with a definitive tissue diagnosis was obtained in all of the 4 cases performed. Metastatic hilar cholangiocarcinoma and recurrent neuroendocrine tumor were diagnosed in 2 patients and followed by placement of a self-expandable metal stent, when possible. In the other 2 patients, a diagnosis of resectable hilar cholangiocarcinoma and poorly differentiated adenocarcinoma of unclear origin without evidence of vascular involvement was made, and plastic stents were placed before surgery; the first patient was found to have peritoneal metastases, and resection was aborted, and in the second patient, a gallbladder tumor was diagnosed in the surgical specimen. Limitation The small number of patients. Conclusions These preliminary data suggest that FVL-EUS used as a primary tool for the evaluation of patients with HBS may be of value and should be further explored in properly designed studies with a meaningful number of patients.
Gradients in coupled-pair theories

Abstract The calculation of analytical gradients for coupled-pair wave functions is discussed. It is emphasized that gradients can only be efficiently evaluated if the CI coefficients minimize the total energy expression. Two CEPA versions are proposed which have this property. CEPA-F has fixed denominator shifts. CEPA-VAR is an approximation to CEPA-2: its denominator shifts are two-third of the pair correlation energies, and the energy formula is minimized with respect to the CI coefficients. Equations are presented for the derivatives of the localized orbitals which are needed in the localized form of CEPA-VAR.
Isolated pulmonary cryptococcosis in pregnancy

Abstract Background: Isolated pulmonary cryptococcosis in an immunocompetent parturient host is a rare event. Little is known about this condition, its prognosis, and its treatment in the immunocompetent pregnant woman. Case: A 28-year-old woman, para 3, was diagnosed with isolated pulmonary cryptococcosis postpartum. She had delivered a healthy neonate at term who revealed no clinical features compatible with maternal-fetal transmission. The woman was monitored closely throughout the course of her disease and radiogic, clinical, and serologic resolution was achieved after treatment with fluconazole. Conclusion: Patients with pulmonary cryptococcosis present with clinical pictures similar to other well-known diseases such as septic pulmonary emboli or choriocarcinoma. Treatment with triazole antifungal therapy yielded favorable results in our patient with this rare condition.
Information-building applications: designing for data exploration and analysis by elementary school students

The propagation of Inquiry Based Learning has lead to many more elementary students interacting with authentic scientific tools and practices. However, the more problematic realities of scientific data collection, such as noise and large data sets, are often deliberately hidden from students. Students will need to confront these realities and be able to make skillful data scoping decisions in order to make sense of ever more prevalent large datasets. We dub software designed to support these activities Information-Building Applications (IBAs). This paper presents the design considerations that went into building an exemplar IBA, PhotoMAT (Photo Management and Analysis Tool), a brief user study to show how the solutions enacted by following these principles are taken up by actual students, and a discussion of how the design considerations identified by our work might be applied to another IBA.
Intrinsic surface atom manipulations in STM and AFM

State-of-the-art first-principles simulations are performed to investigate the possibility of using a tungsten tip in atomic force microscopy (AFM) as a mechanical tool to manipulate the surface atoms of Si(100). Calculations of total energy and electronic structure are used to study the energetics and bonding properties associated with the tip and surface for a variety of atomic configurations. The results predict that under certain protocols the tip can be used effectively to flip dimers on the surface, from one buckled configuration to another, reversibly, and without inducing damage to either the intrinsic surface or the tip. This leads directly to the exciting possibility of using the intrinsic (100) surface of silicon as an ultra-high memory storage device approaching the ultimate limit of one bit of data per atom.
The role of O− ions in the oxidative dehydrogenation of ethane over molybdenum oxide supported on silica gel

The role of 0(-1) ions in the oxidative dehydrogenation of ethane over molybdenum oxide supported on silica gel was further studied by comparing the ethane dehydrogenation kinetics with molecular oxygen and with nitrous oxide (N/sub 2/O) as oxidizing agent. At 350/sup 0/-450/sup 0/C and 76-380 mm Hg ethane and N/sub 2/O, the reaction was first order in both reactants, the ethylene selectivity was independent of reactant partial pressures, and the activation energies of formation of ethylene and CO/sub 2/ were 18.4 and 28.7 kcal/mole, respectively. With oxygen, the rates of formation of ethylene and CO/sub 2/ were zero order in O/sub 2/ and first order in ethane, and the activation energies of ethylene and CO/sub 2/ formation were 23.3 and 27.2 kcal/mole, respectively. The rates were higher with nitric oxide, especially at the lower temperatures tested, e.g., the rate of ethylene formation at 375/sup 0/C was seven times higher with N/sub 2/O than with O/sub 2/. A mechanism was derived for the formation of ethylene in which the O/sup -/ ions generated by N/sub 2/O decomposition are responsible for hydrogen abstraction in the dissociative adsorption of ethane, and the active site consists of at least two molybdenum ions bridged bymore » an oxygen atom. The presence of ethyl radicals on the catalyst surface was confirmed experimentally.« less
Free energies of molecular bound states in lipid bilayers: lethal concentrations of antimicrobial peptides.

The lipid matrix, or the lipid bilayer, of cell membranes is a natural binding site for amphipathic molecules, including antimicrobial peptides, pore-forming proteins, and many drugs. The unique property of pore-forming antimicrobial peptides is that they exhibit a threshold concentration (called the lethal concentration or the minimum inhibitory concentration) for activity, below which no effect is seen. Without this property, antimicrobial peptides would not be effective self-defense weapons, because they would have harmed all cells at any concentration. The question is what gives rise to this unique property? This study provides a free energy description for the origin of a threshold concentration. The same free energy applied differently also explains the binding of drugs that shows no threshold concentrations. The idea is compared with theories of micellar solutions that require a large oligomer size (n ⪞ 15) to achieve a threshold concentration. The elasticity of lipid bilayers makes the phenomena in membranes different. The majority of antimicrobial peptides have a large negative binding energy to the bilayer interface, but the binding causes an expansion in the membrane area, or equivalently a thinning in the membrane thickness. This elastic energy of membrane thinning elevates the energy level of interfacial binding with the peptide concentration, hence gives rise to a threshold concentration for forming pores containing as few as four peptides.
Fibering of Rubber. Time Lag and Its Relation to Rubber Structure

Abstract FOR several years it has been known that in the unstretched condition ordinary rubber acts toward x-rays like an amorphous material, but that, when it is sufficiently stretched, it acts toward the rays like a fibrous material. In 1931 Acken, Singer, and Davey (1) reported that at room temperature a time interval was required to build up the fibrous structure in cyclically stretched rubber. Investigation showed that the time-lag effect could not be accounted for in terms of a temperature change during the act of stretching. Even if all the mechanical energy of stretching were instantaneously changed into sensible heat, the temperature of the rubber sample could not have been increased momentarily by more than 5.2° C., whereas the fibering of rubber continuously stretched at 420 per cent elongation could be demonstrated up to a temperature of 47° C. Experimentally no temperature rise greater than 1.0° C. could be found in the samples used. Since the time-lag effect appeared, therefore, to be a real...
Correlation of respiratory parameters in hamsters with the lung deposition of radiolabeled cigarette smoke

An evaluation was made of the relationship between respiration and deposition of cigarette smoke particulate matter in the lungs of Syrian golden hamsters. The hamsters were exposed to radiolabeled cigarette smoke while their respiratory rates and tidal volumes were monitored and recorded. The amount of total particulate matter deposited in the lungs correlated linearly with the respiratory parameters. For all tests, the sample correlation coefficient for lung deposition with minute volume was 0.75, with tidal volume, 0.84, and with respiratory rate, 0.52. Respiration characteristics of hamsters that had been smoking for 6 months were measured during their course of 12 daily cigarettes. The average volume and rate measurements during the smoke periods were essentially the same as for the beginning hamsters.
Phycovirus SM-1: A Virus Infecting Unicellular Blue-Green Algae

Abstract We describe the purification of a new blue-green algal virus SM-1, which infects only unicellular forms. The new virus appears to be a polyhedron with no obvious tail and with an average diameter of about 88 mμ. Several characteristics indicate that this virus is distinct from the blue-green algal virus LPP-1. Two infectious nucleoproteins were usually found in sucrose-density gradients. The faster component aggregated readily, and its instability appeared to account for the variations in the relative proportion of the two components. The sedimentation coefficient of the slower sedimenting component ( s 20w ) was 1.021–1.029. The nucleic acid is a double-stranded DNA. The new SM-1 virus, unlike the algal virus, LPP-1, does not appear to resemble basic morphological phage types.
The CIE 1931 standard colorimetric observer: Mandatory retirement at age 65?

The CIE system of colorimetry has been stretched to applications in industries and technologies that were not even envisioned when it was established in 1931. In general the standard observer has made this stretch gracefully. However, there has been a rash of recent articles in this and other journals suggesting that perhaps it is time to force the standard observer to retire. Often the apparent failings of colorimetry are due to its improper application or unrealistic expectations. This Color Forum reviews the status of the CIE standard observer and suggests that, while improvements are certainly possible, retirement would be premature.