cssi/SciSciGPT-SciSciNet huggingface dataset:
The endocrine pancreas: insights into development, differentiation, and diabetes

In the developing embryo, appropriate patterning of the endoderm fated to become pancreas requires the spatial and temporal coordination of soluble factors secreted by the surrounding tissues. Once pancreatic progenitor cells are specified in the developing gut tube epithelium, epithelial-mesenchymal interactions, as well as a cascade of transcription factors, subsequently delineate three distinct lineages, including endocrine, exocrine, and ductal cells. Simultaneous morphological changes, including branching, vascularization, and proximal organ development, also influence the process of specification and differentiation. Decades of research using mouse genetics have uncovered many of the key factors involved in pancreatic cell fate decisions. When pancreas development or islet cell functions go awry, due to mutations in genes important for proper organogenesis and development, the result can lead to a common pancreatic affliction, diabetes mellitus. Current treatments for diabetes are adequate but not curative. Therefore, researchers are utilizing the current understanding of normal embryonic pancreas development in vivo, to direct embryonic stem cells toward a pancreatic fate with the goal of transplanting these in vitro generated 'islets' into patients. Mimicking development in vitro has proven difficult; however, significant progress has been made and the current differentiation protocols are becoming more efficient. The continued partnership between developmental biologists and stem cell researchers will guarantee that the in vitro generation of insulin-producing β cells is a possible therapeutic option for the treatment of diabetes.
Total parenteral nutrition in poor prognosis gestational trophoblastic disease.

Abstract From 1978 through 1984, 35 women received therapy for poor prognosis gestational trophoblastic disease (GTD) at Duke University Medical Center. Total parenteral nutrition (TPN) was utilized in nine patients (26%) for reasons including inadequate oral intake, nutritional depletion, and/or bone marrow suppression. Overall survival with follow-up ranging from 12 to 78 months was 88% for the TPN group and 70% for the non-TPN group ( P = 0.38). Median duration of TPN therapy was 4 weeks (2–46 weeks). Intensity of therapy was comparable between the groups. Median weight gain of 0.15 kg/week for the TPN group was significantly greater than the 0.18/kg/week weight loss in the non-TPN group ( P P = 0.006). Future studies need to further define the proper role of TPN in patients with poor prognosis GTD especially in those with severe nutritional deficits.
Effects of redundancy on information-reduction tasks.

Thirty elementary school children sorted dot patterns that were either asymmetrical or symmetrical about (a) a vertical axis, (b) a horizontal axis, or (c) both. Asymmetrical patterns were sorted faster and with fewer errors than the symmetrical patterns (p <.001). Stimulus redundancy interfered with rapid visual disrimination presumably by reducing stimulus uniqueness and distinctness. When the complexity of the input was sufficient to force the Ss to reduce the stimulus to distinctive parts, the retarding effects of redundancy on discrimination were in direct relation to the amount of redundancy and independent of the Ss' chronological age.
Results on the spin structure functions g1 and g2 for the proton

Results of g 1 p are presented for a wide x range 0.003 x Q 2 of 10 GeV 2 . Combining the data with previous experimental results the Bjorken sum rule is confirmed within 10% of the theoretical value. An exploratory measurement for A 2 and g 2 are presented and used to reduce systemetic errors.
Single HSV-amplicon vector mediates drug-induced gene expression via dimerizer system.

A variety of viral vectors have been used to deliver genes into various tissues. Most have typically relied on either viral or cell-specific mammalian promoters to express transgenes. More recently, regulated promoter systems have been developed to fine-tune gene expression. Due to limited transgene capacity in most viral vectors, regulatory elements are typically subcloned into two separate vectors, which must be delivered simultaneously to a target cell. Here, we have cloned all the components of the rapamycin-based "dimerizer" system into the pantropic HSV-amplicon vector and used it to deliver and regulate red fluorescent protein (RFP) expression in cultured cells in a drug-dose-dependent manner. 293T/17 cells infected at an m.o.i. of 1 transducing unit/cell and induced with 20 nM rapamycin resulted in a 25-fold increase in RFP mRNA levels after 24 h as assessed by quantitative RT-PCR. However, due to a reduced ability to detect RFP optically, only a 5-fold induction in the number of RFP-expressing cells was noted by FACS analysis 48 h after infection. Further, there was at least 100-fold variation in the levels of RFP in individual, infected cells in the induced state. Gene induction in several neuronal models, including primary cell culture and organotypic cultures, as well as in rodent brain, was observed.
Molecular cloning of cDNAs encoding the GAP-associated protein p190: implications for a signaling pathway from ras to the nucleus.

Abstract In mitogenically stimulated and tyrosine kinase—transformed cells, a substantial fraction of the ras GTPase-activating protein (GAP) forms a complex with a protein termed p190. We have cloned several cDNAs encoding the p190 protein. Analysis of the predicted protein sequence reveals three distinct domains with homology to previously described sequences. An N-terminal domain of p190 contains sequence motifs that are found in all of the known GTPases. At the C-terminus of the protein is a domain that contains sequences very similar to those found in the breakpoint cluster region gene product, n-chimerin, and rho GAP, all of which have been shown to possess intrinsic GAP activity on small GTPases. Finally, a 778 aa segment in the middle of p190 is nearly identical in sequence to a recently described transcriptional repressor. This raises the possibility that p190, acting via GAP, can transduce signals from p21 ras to the nucleus, perhaps affecting expression of specific cellular genes.
Anatomy and circulation of the canine skin

The skin of the dog has several anatomic differences from human skin. Skin thickness, hair growth, and circulation vary regionally in the dog and between breeds to some degree. Direct cutaneous arteries supply the canine skin. The deep or subdermal layer is closely associated with the panniculus muscle (where present) and should be elevated with the overlying skin during routine flap elevation or undermining procedures. Flaps in the dog elevated without inclusion of a direct cutaneous artery and vein have been termed subdermal plexus flaps to avoid confusing them with random flaps in the human based on musculocutaneous vessels. Axial pattern flaps developed for veterinary clinical use are discussed, several of which have potential for free flap transfer in cutaneous reconstructive surgery.
A Comparison of Three Methods for the Assessment of Foam Stability of Beer

Three methods for measuring foam stability were assessed using nine different beers. The methods were the NIBEM instrument of Haffmans, the device marketed by Steinfurth and the manual procedure developed by Constant. There were reasonable-to-good correlations when the foam stability of all the beers, as determined by the individual methods, were compared one with another. However when individual beers were studied, it appeared that different techniques rank them in somewhat different sequences. All of the methods demonstrated the superior foam stability of examined ales over lagers, however there were some differences in ranking of beer foam quality, in particular with the beers bittered with reduced iso-α-acids, which performed better when assessed by methods that quantified the foam itself, rather than drainage.
Flecainide: Electrophysiologic and antiarrhythmic properties in refractory ventricular tachycardia

Abstract Twenty-two patients with coronary artery disease and spontaneous ventricular tachycardia (VT) or ventricular fibrillation (VF) underwent intracardiac electrophysiologic evaluation and, when possible, ambulatory monitoring before and after therapy with flecainide (mean dose 418 ± 87 mg [mean ±standard deviation]). An average of 4 antiarrhythmic agents were used and were unsuccessful before therapy with flecainide was begun. During 64 ± 16 hours of control Holter monitoring in 16 patients, all had 1 or more salvos of VT, as well as ventricular premature complexes (VPCs). Programmed stimulation during the control period induced VT in 17 of 22 patients. After flecainide therapy, Holter monitoring showed elimination of all forms of VT in all but 1 patient, as well as significant reduction of paired VPCs by 95% (p
Evaluation of the efficiency of human immune system reconstitution in NSG mice and NSG mice containing a human HLA.A2 transgene using hematopoietic stem cells purified from different sources

Severely immunodeficient mice such as the NOD/SCID/IL2rγnull (NSG) strain can be engrafted with human hematopoietic stem cells (HSCs), resulting in chimeric mice containing many components of the human immune system (Human Immune System mice or HIS mice). HIS mice can both support the replication of and recapitulate much of the immunological response to a variety of pathogens, including ones with strict human tropism, such as HIV-1. In an effort to develop a better mouse model for human infectious pathogen infection and possible immune resolution, we compared the human immune system reconstitution of NSG mice following injection with human CD34+ HSCs purified from either fetal liver (FL) or umbilical cord blood (UCB). We analyzed reconstitution in standard NSG mice as well as a derivative of these mice containing an HLA.A2 encoding transgene (NSG.A2). HSCs from both sources effectively reconstituted hematopoietic lineages when injected into NSG mice. In marked contrast, total CD45+ human hematopoietic cells in NSG.A2 mice were well reconstituted by HSCs from UCB but very poorly by HSCs purified from FL. Moreover, the reconstitution of T cell lineages in NSG.A2 mice by HSCs from UCB was inferior to that obtained using NSG mice. We also found that FL CD34+ HSCs contain a much higher percentage of cells with a phenotype consistent with primitive progenitors than UCB HSCs. We discuss possible explanations for the influence of the HLA.A2 transgene on hematopoietic reconstitution using the two sources of HSCs.
A Comprehensive Fuel Spray Model for High Pressure Fuel Injectors

Understanding the physics and chemistry involved in spray combustion, with its transient effects and the inhomogeneity of the spray is quite challenging. For efficient operation of both internal combustion and gas turbine engines, great insight into the physics of the problem can be obtained when a computational analysis is used in conjunction with either an experimental program or through published experimental data. The main area to be investigated to obtain good combustion begins with the fuel injection process and an accurate description of the mean diameter of the fuel particle, injection pressure, drag coefficient, rate shaping etc must be defined correctly. This work presents a methodology to perform the task set out in the previous paragraph and uses experimental data obtained from available literature to construct a semi-empirical numerical model for high pressure fuel injectors. A modified version of a multidimensional computer code called KIVA3V was used for the computations, with improved sub-models for mean droplet diameter, injection pressure, injection velocity, and drop distortion and drag. The results achieved show good agreement with the published in-cylinder experimental data for a Volkswagen 1.9 L turbo-charged direct injection internal combustion engine under actual operating conditions. It is crucial to model the spray distribution accurately, as the combustion process and the resulting temperature distribution and pollutant emission formation is intimately tied to the in-cylinder fuel distribution. The present scheme has achieved excellent agreement with published experimental data and will make an important contribution to the numerical simulation of the combustion process and pollutant emission formation in compression ignition direct injection engines and gas turbine engines.© 2008 ASME
The hyperkalemic Brugada sign.

Abstract Background A few case reports have indicated that hyperkalemia can induce a Brugada pattern in the electrocardiogram. The specific clinical and electrocardiographic features of the hyperkalemic Brugada sign, however, have not been previously described. Methods A case series was collected from hospitalized hyperkalemic patients with a type I Brugada pattern in the electrocardiogram, and a literature review was performed. Electrocardiograms were examined for rhythm and morphology, and clinical characteristics were analyzed. Results Nine new cases with the hyperkalemic Brugada sign were identified with an additional 15 cases found in the literature. Of the 9 cases, 8 were male patients, and all were critically ill; 5 of the 9 died within 48 hours. The mean (±SD) serum potassium level was 7.8 ± 0.5 mEq/L. The mean QRS width was 144 ± 31 milliseconds, and all had abnormal QRS axis. In 6 cases, there was a wide complex rhythm without visible P waves. The clinical and electrocardiographic characteristics of 15 cases found in the literature were remarkably similar to those in our series. Conclusions The hyperkalemic Brugada pattern differs in substantial ways from the electrocardiogram of patients with the genetic Brugada syndrome. Many patients have wide complex rhythms without visible P waves, marked QRS widening, and an abnormal QRS axis. Most patients are male, and many are critically ill. Prompt recognition of this clinical and electrocardiographic entity may expedite the initiation of appropriate treatment for hyperkalemia.
Impacts of 3‐D radiative effects on satellite cloud detection and their consequences on cloud fraction and aerosol optical depth retrievals

[1] We present the first examination on how 3-D radiative transfer impacts satellite cloud detection that uses a single visible channel threshold. The 3-D radiative transfer through predefined heterogeneous cloud fields embedded in a range of horizontally homogeneous aerosol fields have been carried out to generate synthetic nadir-viewing satellite images at a wavelength of 0.67 μm. The finest spatial resolution of the cloud field is 30 m. We show that 3-D radiative effects cause significant histogram overlap between the radiance distribution of clear and cloudy pixels, the degree to which depends on many factors (resolution, solar zenith angle, surface reflectance, aerosol optical depth (AOD), cloud top variability, etc.). This overlap precludes the existence of a threshold that can correctly separate all clear pixels from cloudy pixels. The region of clear/cloud radiance overlap includes moderately large (up to 5 in our simulations) cloud optical depths. Purpose-driven cloud masks, defined by different thresholds, are applied to the simulated images to examine their impact on retrieving cloud fraction and AOD. Large (up to 100s of %) systematic errors were observed that depended on the type of cloud mask and the factors that influence the clear/cloud radiance overlap, with a strong dependence on solar zenith angle. Different strategies in computing domain-averaged AOD were performed showing that the domain-averaged BRF from all clear pixels produced the smallest AOD biases with the weakest (but still large) dependence on solar zenith angle. The large dependence of the bias on solar zenith angle has serious implications for climate research that uses satellite cloud and aerosol products.
Secondary Syphilis with Iris Papules

A 30-year-old man developed bilateral iridocyclitis with iris roseolae and papules three months after the rash of secondary syphilis. The inflammation resolved after treatment with penicillin, intramuscularly, topically given corticosteroids, and cycloplegics. The serum immune-complex levels were slightly increased. Iris angiography showed leakage of fluorescein in the region of the papules and roseolae and from the vessels of the pupillary margin. When the eye was clinically uninflamed, a follow-up angiogram showed leakage of fluorescein from the same areas, suggesting that the inflammatory effect on the iris vessels persisted in the region of the roseolae, the papules, and the sphincter vessels.
Why do not patients receive influenza vaccine in December and January

Background Influenza vaccination levels in older patients have changed little since the mid-1990s. Despite frequent health care visits by a majority of older persons, many missed opportunities continue to occur. Methods Patients were eligible for the study if they were age 50 and older, had not received influenza vaccine during the current season and were making a scheduled visit to one of the 13 study sites in California, New York, or New Mexico for purposes other than vaccination. Through direct observation, we determined if office staff inquired about vaccination status, discussed vaccination, or both. We defined missed opportunities as failure to administer influenza vaccine to patients for whom it was indicated. Results Missed opportunities increased steadily from October to January (P < 0.0001), and were more common when there was no inquiry or discussion (P < 0.00001), among patients aged 50–64 (P < 0.0001) and in California and New Mexico (P = 0.001). A classification tree analysis revealed that lack of inquiry and week of visit contributed most to missed opportunities. Discussion Early in the vaccination season, missed opportunities were uncommon and specific inquiries into or discussion of vaccination did not appear necessary. In December and January, patients tended to be vaccinated only when vaccination was addressed during the visit. Efforts to remind patients about vaccination later in the vaccination season may be essential to achieving higher coverage in the U.S.
Dual role of juvenile hormone in the control of yolk formation in Periplaneta americana

Two immunochemically discrete protein yolk precursors or vitellogenins appear in the blood of adult Periplaneta americana on day 4 or 5 after emergence. Ovariectomy results in a 20-fold increase in blood vitellogenin concentration. Allatectomy prevents the appearance of blood vitellogenin, while normal levels occur following the implantation of corpora allata into allatectomized females or the injection of farnesyl methyl ether into decapitated females, although implanting corpora cardiaca or brains is apparently ineffective. That yolk deposition requires the presence of juvenile hormone, in addition to blood vitellogenin, is indicated by the failure of vitellogenin injections to stimulate yolk deposition in allatectomized females.
Thermocapillary motion of a deformable drop toward a planar wall

Abstract The thermocapillary migration of a deformable drop moving normal to a planar wall is considered. The temperature is assumed to be constant at the wall and approaches a linear field far from the wall. Inertial effects as well as thermal convection are neglected. All physical parameters save surface tension are assumed to be constant and the motion is assumed to be quasi-steady and axisymmetric. A numerical solution procedure based on the boundary integral method is applied. In particular, Green's functions appropriate to the planar wall configuration are used for both the thermal and fluid dynamic portions of the problem. The effects of viscosity ratio, thermal conductivity ratio, and dimensionless rate of change of surface tension with temperature are discussed. Degree of deformation is found to increase with increasing effective capillary number.
Comment on: Varus malalignment negates the structure-modifying benefits of doxycycline in obese women with knee osteoarthritis.

In the current issue, Mazzuca et al (1) report, from a trial of the effect of doxycycline on medial joint space narrowing, the results of post hoc treatment group comparisons in subgroups of varus and non-varus osteoarthritic knees. These analyses were undertaken to ascertain whether varus malalignment decreased the structure-modifying effect of doxycycline. The sample included 379 obese, 45–64 year old women with unilateral knee osteoarthritis (OA). Mazzuca et al found that, in the non-varus osteoarthritic knees, 16-month joint space narrowing was 44% slower and 30-month narrowing was 39% slower in the doxycycline group than in the placebo group. In contrast, in the varus osteoarthritic knees, this difference was blunted; the rate of joint space narrowing was unaffected by doxycycline.
Seedling Nutrient Status before Submergence Affects Survival after Submergence in Rice

Vast rainfed lowland areas in Asia periodically experience flash floods that adversely affect survival and productivity of rice (Oryza saliva L.). Progress has been made in developing more tolerant germplasm, but fewer efforts have been devoted to identifying proper management options. We evaluated the effects of nitrogen (N) and phosphorus (P) added before submergence on seedling survival after submergence. Two experiments were conducted using two cultivars, submergence-tolerant FR13A and intolerant IR42. In the first experiment, N was applied at two different times and, in the second, N and P were used in a fertile and a P-deficient soil. Seedlings (21-d-old) were submerged in concrete tanks for 12 d. Addition of P seems to enhance tolerance of plants grown on P-deficient soils. Survival of both cultivars decreased substantially in seedlings with high N concentration, with higher survival in FR13A. Leaf N and chlorophyll concentration before submergence were higher in N-treated seedlings, whereas chlorophyll a/b ratio was lower. In both cultivars, photosynthesis and root-shoot ratio decreased and chlorophyllase activity increased after submergence with increasing N and with higher activity of chlorophyllase in IR42. Survival was negatively correlated with leaf N concentration, but positively correlated with root-shoot ratio and stem starch concentration before submergence and with chlorophyll concentration and chlorophyll a/b ratio after submergence. Crop establishment could therefore be enhanced in areas where untimely flooding is anticipated by avoiding excessive N application.
Mucin production by human colonic carcinoma cells correlates with their metastatic potential in animal models of colon cancer metastasis.

Abstract Patients with mucinous colorectal cancers characteristically present with advanced disease, however, the relationship between mucin production by colon cancer cells and their metastatic potential remains unclear. We therefore sought to define the relationship between mucin production by human colon cancer cells and metastatic ability by employing animal models of colon cancer metastasis. LS LiM 6, a colon carcinoma cell line with high liver metastasizing ability during cecal growth in nude mice produced twofold more metabolically labeled intracellular mucin and secreted four- to fivefold more mucin into the culture medium compared to poorly metastatic parental line LS174T. This was accompanied by a similar elevation in poly(A)+ RNA detected by blot hybridization with a human intestinal mucin cDNA probe, and increases in mucin core carbohydrate antigens determined immunohistochemically. Variants of LS174T selected for high (HM 7) or low (LM 12) mucin synthesizing capacity also yielded metastases after cecal growth and colonized the liver after splenic-portal injection in proportion to their ability to produce mucin. Inhibition of mucin glycosylation by the arylglycoside benzyl-alpha-N-acetyl-galactosamine greatly reduced liver colonization after splenic-portal injection of the tumor cells. These data suggest that mucin production by human colon cancer cells correlates with their metastatic potential and affects their ability to colonize the liver in experimental model systems.
Hybrid inflation, dark energy and dark matter

Abstract It has been suggested that the dark energy density ρ v ∼ 10 −12 eV 4 in the universe is associated with a metastable (false) vacuum, while the true vacuum has a vanishing cosmological constant. By including supergravity corrections we show how this is naturally realized in realistic supersymmetric hybrid inflation models. With a fundamental supersymmetry breaking scale ∼ TeV , the LSP is not a suitable candidate for cold dark matter. We consider axion physics to overcome this and simultaneously provide a resolution of the MSSM μ problem.
Radioimmunoassays for β-endorphin: Comparison of properties of two antisera☆

Abstract The opioid activity of β-endorphin depends upon a free amino-terminal Tyr residue. Larger precursor peptides are inactive, as is the metabolic product from which Tyr 1 has been cleaved. Immunoassays have the advantage of great sensitivity but the disadvantage of ambiguity. Ambiguity arises when the antigenic determinant is a sequence not required for biological activity. Two antisera are described with antigenic determinants not hitherto reported. One of these is suitable for assays of β-endorphin in human plasma. The other contains an antibody that recognizes β-endorphin only if amino-terminal Tyr is present, thus achieving a coincidence of immunoreactivity and opioid activity.
Fast model-free deconvolution of fluorescence decay for analysis of biological systems

For complex biological systems, conventional analysis of fluorescence intensity decay in terms of discrete exponential components cannot readily provide a true representation of the underlying fluorescence dynamics. We investigate an alternative nonparametric method for the analysis of time-resolved fluorescence data from biochemical and biological systems based on the expansion of fluorescence decay in a discrete Laguerre basis. We report that a unique Laguerre expansion can be found for fluorescence intensity decays of arbitrary form with convergence to a correct solution significantly faster than conventional multiexponential approximation methods. The Laguerre expansion coefficients are shown to be highly correlated with intrinsic fluorescence lifetimes and allow direct characterization of the fluorescence dynamics. A novel method for prediction of concentrations in mixtures of biochemical components using these coefficients is developed and successfully tested (prediction error <2%) using data from different mixtures of fluorescence lifetime standards. These findings suggest that the use of Laguerre expansion coefficients is a fast approach for the characterization and discrimination of complex biological systems such as tissues and cells, and that the method has potential for applications of fluorescence lifetime techniques to tissue diagnostics and imaging microscopy of living cells.
Modeling Ice Crystal Aspect Ratio Evolution during Riming: A Single-Particle Growth Model

AbstractThis paper describes and tests a single-particle ice growth model that evolves both ice crystal mass and shape as a result of vapor growth and riming. Columnar collision efficiencies in the model are calculated using a new theoretical method derived from spherical collision efficiencies. The model is able to evolve mass, shape, and fall speed of growing ice across a range of temperatures, and it compares well with wind tunnel data. The onset time of riming and the effects of riming on mass and fall speed between −3° and −16°C are modeled, as compared with wind tunnel data for a liquid water content of 0.4 g m−3. Under these conditions, riming is constrained to the more isometric habits near −10° and −4°C. It is shown that the mass and fall speed of riming dendrites depend on the liquid drop distribution properties, leading to a range of mass–size and fall speed–size relationships. Riming at low liquid water contents is shown to be sensitive to ice crystal habit and liquid drop size. Moreover, very...
Government Institutional Effects on the Value of Seasonal Climate Forecasts

The impact of government institutions on the value of improved climate forecasts is examined. Results suggest that crop insurance and earned income tax credit have little effect on the expected change in after-tax cash flows. Federal tax law has only a modest influence. As expected, the disaster program decreases the value of improved climate forecasts. With no price changes, the farm program lowers the value of the forecasts because of the acreage reduction provisions. With at least some price decreases, the farm program increases the value of climate forecasts. Here, the price supports override the acreage reduction provisions.
Roles of histone acetyltransferases and deacetylases in gene regulation

Acetylation of internal lysine residues of core histone N-terminal domains has been found correlatively associated with transcriptional activation in eukaryotes for more than three decades. Recent discoveries showing that several transcriptional regulators possess intrinsic histone acetyltransferase (HAT) and deacetylase (HDAC) activities strongly suggest that histone acetylation and deacetylation each plays a causative role in regulating transcription. Intriguingly, several HATs have been shown an ability to acetylate nonhistone protein substrates (e.g., transcription factors) in vitro as well, suggesting the possibility that internal lysine acetylation of multiple proteins exists as a rapid and reversible regulatory mechanism much like protein phosphorylation. This article reviews recent developments in histone acetylation and transcriptional regulation. We also discuss several important, yet unanswered, questions.
Higher order levermore theory

Abstract The transport analysis of Levermore which in lowest order leads to a flux-limited diffusion equation, is extended to the next highest order. The resulting approximate description of transport processes is diffusion-like in character but is not flux limited.
Quantum mechanics and deterministic chaos

Abstract Quantum mechanical equations of motion are obtained for a system consisting of a very large number of two types of interacting bosons subject to a time-dependent external force. Under suitable choice of parameters of the Hamiltonian of the system, the equations of motion are equivalent to those describing an electric circuit consisting of a Josephson junction in series with an external capacitor and a sinusoidal voltage, or alternatively equivalent to an undamped driven pendulum. The system is capable of exhibiting deterministic chaos (extreme sensitivity to initial conditions).
Factorization strategies for third-order tensors

Abstract Operations with tensors, or multiway arrays, have become increasingly prevalent in recent years. Traditionally, tensors are represented or decomposed as a sum of rank-1 outer products using either the CANDECOMP/PARAFAC (CP) or the Tucker models, or some variation thereof. Such decompositions are motivated by specific applications where the goal is to find an approximate such representation for a given multiway array. The specifics of the approximate representation (such as how many terms to use in the sum, orthogonality constraints, etc.) depend on the application. In this paper, we explore an alternate representation of tensors which shows promise with respect to the tensor approximation problem. Reminiscent of matrix factorizations, we present a new factorization of a tensor as a product of tensors. To derive the new factorization, we define a closed multiplication operation between tensors. A major motivation for considering this new type of tensor multiplication is to devise new types of factorizations for tensors which can then be used in applications. Specifically, this new multiplication allows us to introduce concepts such as tensor transpose, inverse, and identity, which lead to the notion of an orthogonal tensor. The multiplication also gives rise to a linear operator, and the null space of the resulting operator is identified. We extend the concept of outer products of vectors to outer products of matrices. All derivations are presented for third-order tensors. However, they can be easily extended to the order-p ( p > 3 ) case. We conclude with an application in image deblurring.
Laser mass spectrometry of oligonucleotides with isomer matrices

Various isomer matrices were used for laser-desorption ionization of mixtures of oligomers. It was found that the efficiency of production of oligomer ions changed drastically when different isomers were used as matrices. For selected matrix materials, parent oligomer ions with sizes up to 64 bases were observed.
Management responses to the problem of incidental catch in fishing: A comparative analysis of the EU, Norway, and the Faeroe Islands

Abstract The article addresses incidental catch as a two-level management problem for systems that regulate fish catches. The first level is legal and concerns the problem of establishing clear and legitimate criteria for criminal liability. The second level is environmental and concerns the efficacy of chosen liability criteria in resource conservation. The article compares and explains the solutions chosen by Norway, the Faeroe Islands, and the EU. Each solution constitutes a distinct form of fisheries management. It is argued that national choices are determined by administrative capacity for implementation and political autonomy in the distribution of fishing rights.
Contamination of fish by 2, 3, 7,8-tetrachlorodibenzo-p-dioxin: a survey of fish from major watersheds in the united states

Abstract A survey of contamination of fish from major watersheds in the United States by 2,3,7,8-TCDD has been conducted by the U.S. EPA. Bottom feeding and predator fish were collected at 90 statistically selected and 305 regionally selected sites and analyzed by GC/MS. It was found that 19% of the statistically sampled sites and 31% of the regionally selected sites were contaminated at or above a minimum level of detection varying from 0.5 to 2.0 pg/g. Ten percent of all samples were contaminated at levels greater than 5.0 pg/g. It was also observed that a subset of samples collected at sites near discharge from pulp/paper manufacture (N=28) had a higher frequency of TCDD contamination above 5.0 pg/g (38%). This subset of samples also contained the sample of the greatest level of TCDD contamination (85 pg/g).
Analysis of ultrashort pulse laser-material interaction using the two-temperature model

Ultrafast or ultrashort pulse lasers are increasingly being used for micro and nano-manufacturing. Because of the extremely short pulsewidth, there is usually not enough time for energy equilibrium to be established between the electrons and lattice in metals. Thus, instead of the conventional heat conduction model, the two-temperature model (TTM) is used to analyze laser-matter interactions for ultrashort pulse lasers. However, currently available non-linear two-temperature models generally require high computation capacity and long calculation time. In this study, a laser-matter interaction analysis strategy for a simplified dimensionless linear two-temperature model (SDLTTM) with proper heat source terms is developed to provide a quick and effective analytical method. SDLTTM is derived from a non-linear TTM with an assumption of constant material properties. The analytical solutions of the SDLTTM for lattice and electron temperatures for selected heat sources are obtained in the form of infinite series, and compared with other non-linear TTMs and experimental results for the electron temperature. Good correlation is obtained with the experimental results. Finally, the limitations of the SDLTTM, which result from the linearization assumption, are discussed.© 2006 ASME
Opioid Tolerance Development: A Pharmacokinetic/Pharmacodynamic Perspective

The opioids are commonly used to treat acute and severe pain. Long-term opioid administration eventually reaches a dose ceiling that is attributable to the rapid onset of analgesic tolerance coupled with the slow development of tolerance to the untoward side effects of respiratory depression, nausea and decreased gastrointestinal motility. The need for effective-long term analgesia remains. In order to develop new therapeutics and novel strategies for use of current analgesics, the processes that mediate tolerance must be understood. This review highlights potential pharmacokinetic (changes in metabolite production, metabolizing enzyme expression, and transporter function) and pharmacodynamic (receptor type, location and functionality; alterations in signaling pathways and cross-tolerance) aspects of opioid tolerance development, and presents several pharmacodynamic modeling strategies that have been used to characterize time-dependent attenuation of opioid analgesia.
Nanoscale fabrication by interferometric lithography

ABSTRACT hiterferometric lithography (IL) techniques provide a demonstrated, low-cost, large area nanoscale patterning capability withfeature resolution to 50 nm. Combining IL with anisotropic etching (both by reactive-ion etching and by KOH wet etching)and with 3-D oxidation techniques provides a suite of techniques that accesses a broad range of Si nanostructures (as small as10 mu) over large areas and with good uniformity. Optical characterization includes measurements of reflectivity for a widerange of 1D grating profiles, and Ra.man scattering characterization of Si nanostructures. Three regimes are found for theRaman scattering: bulk (to linewidths of 200 nm), resonant enhanced (- 50 nm linewidths) and asymmetry and splitting(lmewidths < 20 nm).Keywords: interferometric lithography, Si nanoscale structures, Si quantum wires, Si photolummescence L INTERFEROMETRIC LITHOGRAPHY We have investigated interferometric lithography (IL) as a cost-effective alternative towards nanoscale patterning. IL tech-mques have been demonstrated to produce uniform nm-scale structures over large areas at low cost. The period for IL isAi2sinO, where 20 is the intersection angle between the two exposing laser beams. There is no constraint on the feature di-mension, only the period. Nonlinear response of photoresist and other processing techniques allow linewidths as small as 10urn, limited only by the uniformity and process controL For readily available laser sources from 0.488- to 0.l93-pnn at 0=75°,this translates into periods 0.25-0.1 jnn with linewidths of< 0.12-0.05 tm.Single exposure interferometric grating fabrication has a long history'2 Figure 1 shows a typical experimental configurationin which an expanded and collimated laser beam is incident on a Fresnel mirror (FM) arrangement mounted on a rotationstage3 for period variation. The mirror and sample stages have tilt & tip adjustments, the sample stage is equipped with in-plane rotation adjustment as well. The interference between two beams one directly incident on the wafer on one side of theFM and the second reflected from the mirror mounted on the other side of the FM, results in a periodic pattern )J2sinO, where0 can be precisely varied by the computer-controlled rotation stage. Grating patterns are first fonned in photoresist (PR) fol-lowed by a pattern transfer to the underlying substrate. Figure 2 shows examples of 360- and 250-nm period photoresistgratings fabricated on a bottom-ARC-coated Si wafer. These structures were fabricated with laser exposure at ?=355 am(third harmonic of a YAG laser) in Shipley 505-A positive photoresist. The grating linewidths were 180- and 130-nm re-spectively at a thickness of 500 urn4. At smaller periods, photoresist collapse5 and horizontal thinning during the develop-ment process limit the achievable aspect ratios and force the use of thinner ( 100-200 urn) PR films.
Higher Education in a World Market: An Historical Look at the Global Context of International Study.

Recognizing that academic, scientific and technological strengths have become increasingly important in international relations, this study hypothesizes that the flow of knowledge resources among nations is interconnected with global political, economic and cultural relationships. As a means of validating this premise, this study analyzes one component of academic interaction - international study at the level of higher education. This article outlines changes in international study patterns in the decades following World War n and explores how the postwar context affected international exchange relationships. International exchange during the 1960s and 1970s indicated strong participation by students from Third World nations and the popularity of five industrialized host nations. These relationships are explored through a statistical study of the flow of students from 18 developing nations out to the world and to the United States in particular. The findings assess the importance of key economic factors (such as involvement in global trade and concentration of trade), educational variables (including national emphasis on education and the availability of domestic opportunities) and political arenas (such as international assistance and scholarship dependency) in determining international study patterns. As current shifts in our postwar world order unfold before us, better understanding of historical factors underlying international exchange may be instrumental as we anticipate its future within the context of new geopolitical alliances.
Cost of traumatic spinal cord injury in a population-based registry

This prospective study examines a population based cohort of 115 Coloradans identified as having an acute traumatic spinal cord injury by the Spinal Cord Injury Early Notification System in 1989. Comprehensive medical cost and complication data were collected for the first 2 years of survival. Unlike previous cost studies, this group represents the broad spectrum of spinal cord injured persons, reflected in a truly population based sample. Nearly 22 million dollars were spent during the first 2 years post injury on behalf of these Coloradans. Care provided to the 27 persons with Frankel A, B or C tetraplegia accounted for $10.9 million (50%); $7.6 million (35%) was spent providing care for the 36 people with Frankel A, B or C paraplegia; and the remaining $3.3 million (15%) was required for services provided to the 52 persons who had resolved to either Frankel D or E at acute care discharge. Of the $6.3 million that was spent post hospital discharge, $2.5 million (39%) is directly attributable to in-home care, and another $2.0 million (32%) is directly attributable to secondary medical complications. The most expensive complications occurred in the neurological, skin, respiratory and orthopedic body systems.
The Vitamin K-dependent Carboxylase Has Been Acquired by Leptospira Pathogens and Shows Altered Activity That Suggests a Role Other than Protein Carboxylation

Leptospirosis is an emerging infectious disease whose pathology includes a hemorrhagic response, and sequencing of the Leptospira interrogans genome revealed an ortholog of the vitamin K-dependent (VKD) carboxylase as one of several hemostatic proteins present in the bacterium. Until now, the VKD carboxylase was known to be present only in the animal kingdom (i.e. metazoans that include mammals, fish, snails, and insects), and this restricted distribution and high sequence similarity between metazoan and Leptospira orthologs strongly suggests that Leptospira acquired the VKD carboxylase by horizontal gene transfer. In metazoans, the VKD carboxylase is bifunctional, acting as an epoxidase that oxygenates vitamin K to a strong base and a carboxylase that uses the base to carboxylate Glu residues in VKD proteins, rendering them active in hemostasis and other physiologies. In contrast, the Leptospira ortholog showed epoxidase but not detectable carboxylase activity and divergence in a region of identity in all known metazoan VKD carboxylases that is important to Glu interaction. Furthermore, although the mammalian carboxylase is regulated so that vitamin K epoxidation does not occur unless Glu substrate is present, the Leptospira VKD epoxidase showed unfettered epoxidation in the absence of Glu substrate. Finally, human VKD protein orthologs were not detected in the L. interrogans genome. The combined data, then, suggest that Leptospira exapted the metazoan VKD carboxylase for some use other than VKD protein carboxylation, such as using the strong vitamin K base to drive a new reaction or to promote oxidative damage or depleting vitamin K to indirectly inhibit host VKD protein carboxylation.
Two band model of a disordered semiconducting binary alloy in the coherent potential approximation

Abstract Formalism of the coherent potential approximation is extended to include the two band case. Single site energy of the one band case is replaced by a 2 × 2 matrix which varies randomly from site to site according to the occupancy of the site. Cases treated explicitly correspond to fully disordered binary alloys. Band gap and band widths are chosen as representative of typical semiconductor values. Concentrations, band gaps, gap centers, and band mixing are all varied systematically. Results are exhibited for the total densities of states and their parentage. Various limits of splitband and gap closure are shown by phase diagrams.
TGIF, a gene associated with human brain defects, regulates neuronal development.

5′-TG-3′-interacting factor (TGIF) is an atypical homeodomain protein. In vitro studies have shown that TGIF can repress transcription mediated by either of two signaling pathways: TGF-β and retinoic acid signaling. Mutations in TGIF have been detected in patients with holoprosencephaly (HPE), a severe brain malformation associated with mental retardation. Thus, TGIF must play an essential role in nervous system development. However, the precise function of TGIF during vertebrate neural development is unknown. To investigate the in vivo role of TGIF, we overexpressed TGIF in the developing chick neural tube. Overexpressed TGIF decreased expression of specific genes expressed in dorsally restricted domains of the neural tube, including Cath1, Msx2, Pax6, and Wnt1. In contrast, the expression of other transcription factors, including those necessary for ventral fate such as Nkx2.2, was not affected. Furthermore, a missense mutation in TGIF identified in an HPE patient disrupted the activity of TGIF. In addition, the related protein TGIF2 did not demonstrate the same activity as TGIF. Our data suggest that TGIF plays an important role in regulating the expression of genes expressed in specific dorsal–ventral domains during neural development. Developmental Dynamics 235:1482–1490, 2006. © 2006 Wiley-Liss, Inc.
Development of an expression strategy using a lytic phage to trigger explosive plasmid amplification and gene expression.

Development of an Expression Strategy Using a Lytic Phage to Trigger Explosive Plasmid Amplification and Gene Expression†
Using COTS tools in the development of a model based avionics architecture tool

Information and discussion of the development of an Avionics Architecture Tool that is model-based using commercial off the shelf (COTS) products will be provided. Statemate Magnum from I-Logix Inc. was used in this work. A number of areas of interest will be discussed, including the user and institutional needs affecting tool design, development, and deliverables, how plug-and-play general component models is used for avionics architecture rapid prototyping, the basic architecture of a general component model, and preliminary results of utilising the tool to develop a “straw man” avionics architecture.