cssi/SciSciGPT-SciSciNet huggingface dataset:
Cathepsin L increases invasion and migration of B16 melanoma

Most cancers express elevated protease levels which contribute to certain aspects of tumor behavior such as growth, metastatic spread, and angiogenesis. Elevation of the cathepsins of the cysteine protease family correlates with increased invasion of tumor cells. Cysteine proteases such as cathepsins B, H and L type participate in tumor cell invasion as extracellular proteases, yet are enzymes whose exact roles in metastasis are still being elucidated. We have examined the role of cathepsin L in highly metastatic B16F10 murine melanoma cells through genetic antisense constructs of cathepsin L. The effects of cathepsin L antisense were examined for melanoma cell proliferation, invasion, migration and adhesion. Antisense expression of cathepsin L, while decreasing enzyme activity in cell lysates, did not influence cell proliferation. Cathepsin L contributed to melanoma cell invasion and also augmented melanoma cell migration. Further, we demonstrated the adhesion of cathepsin L down-regulated clones was unaltered to fibronectin, laminin, and collagen. Finally, the inhibition of melanoma cell migration via down-regulation of cathepsin L appears to be independent of cystatin C expression. This study shows that cathepsin L facilitates high metastatic B16 melanoma cell invasion and migration. The mechanism of migration inhibition by decreased cathepsin L is independent of cystatin C levels. Since metastasis depends upon both the invasiveness and migration of tumor cells, cathepsin L may be a therapeutic target of strong clinical interest.
Erratum: “Evaluation of an electron Monte Carlo dose calculation algorithm for electron beams”.

In Vol 9, No 3 (2008) Evaluation of an electron Monte Carlo dose calculation algorithm for electron beam by Angie Hu, Haijun Song, Zhe Chen, Sumin Zhou, Fangfang Yin. Figure 2 should be as follows
A mixed integer programming model for a two line CONWIP-based production and assembly system

Abstract In this paper, a nonlinear mixed integer programming model was developed for a CONWIP-based production system where an assembly station is fed by two parallel fabrication lines. Raw materials are processed through the two fabrication lines. The processed parts are assembled to produce final products at the assembly station. The performance of the production system is measured by the total set-up time and the work load balance on the fabrication lines. The developed model is a nonlinear integer programming model consisting of two travelling salesman problem (TSP) sub-models. The nonlinear terms in the model was partially linearized and solved by enumerating a series of solutions of the TSP sub-problems. Optimal part assignment, production sequence and lot sizes are simultaneously determined by solving the problem. Optimal solutions of small size problems were obtained and are presented to illustrate the developed model.
Comparison of capillary blood flow in the nailfold circulations of young and elderly men

This study investigated the effects of aging on capillary dynamics in the human skin by comparison of capillary blood flow velocity (CBV), capillary diameter and volume capillary blood flow (CBF) in the looped capillaries within the dermal papillae of nailfolds in young (Y — mean age 26 yr) and elderly (E — mean age 63 yr) male subjects. Both toe and finger nailfolds were studied. Quantitative measurements were made only in vessels with relatively straight arterial and venous branches. However, qualitative comparisons were also made of the number of capillaries per field and the general structure of the capillaries. Flow velocity (CBV) was significantly lower in both the toe and finger nailfolds of the E compared to the Y subjects (P≤ 0.050). There was no significant difference in capillary diameter, therefore, volume flow (CBF) was also lower in the E subjects. Respective values of CBF in the toe nailfolds of the Y and E groups were: 1.41 × 104 u3/sec and 0.76 × 104 u3/sec (P ≤ 0.075). Corresponding values for the finger nailfolds were: 2.27 × 104 u3/sec and 1.35 × 104 u3/sec for the Y and E subjects (P ≤ 0.050). There were no significant differences in the number of capillaries per field between the groups although there was a trend towards fewer vessels in the toe nailfolds of the elderly. The elderly also had a higher percentage of tortuous vessels in their toe nailfolds compared to the Y subjects. This observation vis-a-vis a tendency towards fewer vessels in the toe nailfolds of the E subjects indicates that aging may have a more pronounced effect on total capillary flow in this region than indicated by CBF alone.
Measurement of the Second Order Coherence of Pseudo-Thermal Light in the Azimuthal Degree of Freedom

Using an angular version of the Hanbury Brown Twiss interferometer, we show for the first time second-order interference in the azimuthal degree of freedom, which exhibits higher resolution fringes than if coherent light were used.
Risk of Reintubation in Neurosurgical Patients

Reintubation among neurosurgical patients is poorly characterized. The aim of this study was to delineate the rate of reintubation among neurosurgical patients. In addition, we seek to characterize the patient demographic features, comorbidities, and surgical characteristics that may be associated with reintubation among neurosurgical patients. This is a retrospective cohort study conducted in the setting of hospitals participating in the American College of Surgeons’ National Surgical Quality Improvement Program between 2005 and 2010. All adult patients undergoing neurosurgery under general anesthesia were included. Exclusion criteria were preoperative mechanical ventilation or pneumonia prior to surgery. Reintubation was defined as placement of an endotracheal tube or mechanical ventilation within 48 h after surgery. Among 17,483 eligible patients, 74 (0.42 %; 95 % CI 0.33–0.52 %) required reintubation within 48 h of surgery. In multiple logistic regression, the following were associated with increased risk of reintubation: age >65 years (OR 2.1; 95 % CI 1.3–3.4), preoperative renal failure (OR 2.9; 95 % CI 1.0–8.5), quadriplegia (OR 8.2; 95 % CI 3.3–20.3), COPD (OR 2.1; 95 % CI 1.0–4.3), operative time >3 h (OR 2.9; 95 % CI 1.8–4.8), and higher ASA class (OR per point, 2.1; 95 % CI 1.4–3.1). Spinal surgery was found to be protective relative to cranial neurosurgery or endarterectomy (OR 0.3; 95 % CI 0.2–0.5). Reintubation after neurosurgery is associated with older patients with a greater number of comorbidities. In particular, renal, pulmonary, and severe neurologic comorbidities; longer operative duration; and cranial, rather than spinal, pathology were associated with increased risk for reintubation. These findings may be helpful in triage decisions regarding postoperative intensity of care and monitoring.
Infrared spectroscopy of helium nanodroplets: novel methods for physics and chemistry

Helium nanodroplets have emerged as a new and exciting medium for studying the structure and dynamics of both this quantum solvent and impurities that can be doped into (onto) and grown inside (on the surface) of the droplets. Spectroscopic studies of these molecular impurities can provide detailed information on helium as a solvent and its interaction with the solute. This is particularly important given that helium is completely transparent to photons below 20 eV, making the direct spectroscopic study of liquid helium problematic. Since liquid helium is an extremely weak solvent, the corresponding perturbations to the spectrum of the solute molecules are often minor; really only evident because of the high resolution that is often achieved in such studies. As a result, helium nanodroplet spectra often resemble the corresponding gas-phase results. Indeed, for the case of rotational spectroscopy, the gas-phase Hamiltonian is often sufficient to describe the system, with the effects of the solvent being to...
Key Technologies Research of the Interoperable Model Verification Based on CIM/E

Power Grid in China integration running trend makes EMS(Energy Management System) at all levels of information exchange between the increasingly urgent demand. And CIM is the most important base information. In order to solve the model information differences between different EMS, this paper analyzes the current EMS model information related to the standardization of applications, from standard CIM model, the model file formats and file content model three aspects, based on interoperable standards IEC61970 process-oriented information model calibration and validation process for each part of the key technologies are discussed in detail. Through the practical application of the method validation results show that the calibration method is reasonable and correct.
Individual trabeculae segmentation (ITS)-based morphological analysis of high-resolution peripheral quantitative computed tomography images detects abnormal trabecular plate and rod microarchitecture in premenopausal women with idiopathic osteoporosis.

Idiopathic osteoporosis (IOP) in premenopausal women is a poorly understood entity in which otherwise healthy women have low-trauma fracture or very low bone mineral density (BMD). In this study, we applied individual trabeculae segmentation (ITS)–based morphological analysis to high-resolution peripheral quantitative computed tomography (HR-pQCT) images of the distal radius and distal tibia to gain greater insight into skeletal microarchitecture in premenopausal women with IOP. HR-pQCT scans were performed for 26 normal control individuals and 31 women with IOP. A cubic subvolume was extracted from the trabecular bone compartment and subjected to ITS-based analysis. Three Young's moduli and three shear moduli were calculated by micro–finite element (µFE) analysis. ITS-based morphological analysis of HR-pQCT images detected significantly decreased trabecular plate and rod bone volume fraction and number, decreased axial bone volume fraction in the longitudinal axis, increased rod length, and decreased rod-to-rod, plate-to-rod, and plate-to-plate junction densities at the distal radius and distal tibia in women with IOP. However, trabecular plate and rod thickness did not differ. A more rod-like trabecular microstructure was found in the distal radius, but not in the distal tibia. Most ITS measurements contributed significantly to the elastic moduli of trabecular bone independent of bone volume fraction (BV/TV). At a fixed BV/TV, plate-like trabeculae contributed positively to the mechanical properties of trabecular bone. The results suggest that ITS-based morphological analysis of HR-pQCT images is a sensitive and promising clinical tool for the investigation of trabecular bone microstructure in human studies of osteoporosis. © 2010 American Society for Bone and Mineral Research.
Endurance training ameliorates complex 3 deficiency in a mouse model of Barth syndrome

Barth syndrome (BTHS) is an X-linked metabolic disorder that causes cardiomyopathy in infancy and is linked to mutations within the Tafazzin (TAZ) gene. The first mouse model, a TAZ knockdown model (TAZKD), has been generated to further understand the bioenergetics leading to cardiomyopathy. However, the TAZKD model does not show early signs of cardiomyopathy, and cardiac pathophysiology has not been documented until 7–8 months of age. Here we sought to determine the impact of endurance training on the cardiac and skeletal muscle phenotype in young TAZKD mice. TAZKD exercise trained (TAZKD-ET) and control exercise trained (CON-ET) mice underwent a 35-day swimming protocol. Non-trained aged matched TAZKD and CON mice were used as controls. At the end of the protocol, cardiac MRI was used to assess cardiac parameters. Cardiac MRI showed that training resulted in cardiac hypertrophy within both groups and did not result in a decline of ejection fraction. TAZKD mice exhibited a decrease in respiratory complex I, III, and IV enzymatic activity in cardiac tissue compared to control mice; however, training led to an increase in complex III activity in TAZKD-ET mice resulting in similar levels to those of CON-ET mice. 31P magnetic resonance spectroscopy of the gastrocnemius showed a significantly lowered pH in TAZKD-ET mice post electrical-stimulation compared to CON-ET mice. Endurance training does not accelerate cardiac dysfunction in young TAZKD mice, but results in beneficial physiological effects. Furthermore, our results suggest that a significant drop in intracellular pH levels may contribute to oxidative phosphorylation defects during exercise.
Some properties of r.f.-sputtered hafnium nitride coatings

Abstract Hafnium nitride coatings were deposited by reactive r.f. sputtering from a hafnium target in nitrogen and argon gas mixtures. The rate of deposition, the composition, the electrical resistivity and the complex index of refraction were investigated as functions of the target-to-substrate distance and the nitrogen fraction f N2 in the sputtering atmosphere. It was found that the relative composition of the coatings is independent of f N2 for values above 0.1. The electrical resistivity of the hafnium nitride films changes over 8 orders of magnitude when f N2 changes from 0.10 to 0.85. The index of refraction is almost constant at 2.8(1−0.3 i ) up to f N =0.40 then decreases to 2.1(1−0.1 i ) for higher values of f N2 .
Diagnostic Cytology in Veterinary Medicine: A Comparative and Evidence-Based Approach

Diagnostic cytology is a core veterinary pathology service involving specimens from domestic animals, laboratory animals, and exotic species. Evidence-based application of cytopathology involves management of preanalytical factors, and thorough evaluation of the diagnostic accuracy of the technique in each species and for all specimen types. Unique to veterinary medicine is the reliance on cytology as the basis for crucial medical decisions such as humane euthanasia, especially when the patient is critically ill or when financial considerations limit diagnostic and therapeutic options. This article reviews the cytologic criteria for the diagnosis of selected neoplastic and infectious diseases.
TNF- α Antagonist and Infection in Rheumatoid Arthritis

Background: Anti-TNF treatment may increase infection risk, although this has been difficult to study because the timing of anti-TNF treatment is driven by disease activity, which may influence infection susceptibility leading to confounding that varies over time. We evaluated the association between anti-TNF initiation in rheumatoid arthritis (RA) patients on disease modifying anti-rheumatic drugs (DMARD) and infection using multiple approaches adjusting for time-varying confounding. Methods: 383 anti-TNF-naive RA patients on ≥1 non-biologic-DMARD at enrollment from the Brigham and Women’s Rheumatoid Arthritis Sequential Study (BRASS) were followed up to two years. Pooled logistic regressions estimated the association between anti-TNF and infection by including time-varying covariates in the adjusted models and inverse probability treatment weighting (IPTW). Results: Adjustment for time-varying disease activity and other suspected confounders yielded non-statistically significant positive associations between antiTNF start and infection regardless of analytic approach (RRmvar_adj = 2.1, 95% CI: 0.8 - 5.8). Conclusions: Incorporating changing clinical status, and treatment indications and consequences, yielded consistently (though not significantly) elevated relative risks of infection associated with anti-TNF initiation. Due to limited statistical power, we cannot draw firm conclusions. However, we have illustrated multiple approaches adjusting for potential time-varying confounding in longitudinal studies and hope to replicate the approaches in larger studies.
Evidence for a unique expression of CD4 on murine vaginal CD4+ cells.

Summary Mucosal cell-mediated immunity (CMI) by CD4+ T cells is postulated to be important for host defence against several vaginal pathogens. In addition to the recognized phenotypic distinctions of resident vaginal T lymphocytes, we recently provided evidence by fluorescence-activated cell sorter (FACS) that murine vaginal CD4+ T lymphocytes, are differentially recognized by two epitope-distinct anti-CD4 antibodies, suggesting that the CD4 protein on vaginal CD4+ cells is atypically expressed. In the present study, we confirm this by FACS and immunohistochemistry under non-denaturing conditions using two additional anti-CD4 antibodies. However, positive immunohistochemical staining of vaginal CD4+ cells under denaturing conditions revealed that the CD4 epitope in question is indeed present within the CD4 protein. Using reverse transcription polymerase chain reaction, amplification of CD3, T-cell receptor-β (TCR-β), and TCR-δ mRNA from lymph node and vaginal tissue, and CD4 mRNA from lymph node tissue was demonstrable. In contrast, amplification of CD4 mRNA from vaginal tissue, vaginal enriched lymphoid cells, or a purified (FACS-sorted) population of vaginal-specific CD4+ cells using two distinct primer sets was not demonstrable. Altogether, our results provide evidence that the CD4 protein on vaginal CD4+ T cells is conformationally distinct compared with its systemic counterpart, either as a result of a unique CD4 mRNA sequence or from a stable interaction of soluble CD4 with the surface of vaginal T cells.
Perturbations to the active site of phosphotriesterase

Phosphotriesterase catalyzes the hydrolysis of organophosphate nerve agents. Four amino acid residues, located within the active site pocket, were mutated in an effort to ascertain the roles that these groups play in the structure and function of this enzyme. Tryptophan-131 is located at the entrance to the binuclear metal center, and the indole ring is positioned to suggest that it could provide a hydrophobic site for interaction of the aromatic leaving group with optimized substrates. The W131F mutant displays catalytic constants for the hydrolysis of paraoxon that are essentially the same as those of the wild type enzyme. However, the Km value for the W131A mutant is elevated by a factor of 6, consistent with a role for this residue in substrate binding. Aspartate-253 is hydrogen bonded to His-230 which, in turn, is directly ligated to the more solvent-exposed metal ion. The D253N mutant possesses catalytic constants that are virtually the same as those of the wild type enzyme, while the D253A mutant i...
Adapting optical-flow to measure object motion in reflectance and x-ray image sequences (abstract only)

This paper adapts Horn and Schunck's work on optical flow to the problem of determining arbitrary motions of objects from 2-dimensional image sequences. The method allows for gradual changes in the way an object appears in the image sequence, and allows for flow discontinuities at object boundaries. We find velocity fields that give estimates of the velocities of objects in the image plane. These velocities are computed from a series of images using information about the spatial and temporal brightness gradients. A constraint on the smoothness of motion within an object's boundaries is used. The method can be applied to interpretation of both reflectance and x-ray images. Results arc shown for models of ellipsoids undergoing expansion, as well as for an x-ray image sequence of a beating heart.
The poor, the rich, and the insecure elderly caught in between.

Although the elderly are as well or perhaps better off on average than younger groups, measures of the elderly's economic well-being have to gauge the security of their income and assets relative to the financial and health problems they may face. These measures include the adequacy of older Americans' health insurance vis-a-vis their health status, and the sufficiency of their resources to meet possible contingencies, such as severe inflation and costs of long-term care. By applying such measures to the 1984 Survey of Income and Program Participation, 4.5 million elderly may be categorized as economically insecure. Action is needed to ease the insecurity current public and private insurance policy implicitly imposes on this group, which constitutes 20 percent of the elderly population.
Effects of modified Cary and Blair medium on recovery of nonhemolytic Pasteurella haemolytica from Rocky Mountain bighorn sheep (Ovis canadensis canadensis) pharyngeal swabs.

Modified Cary and Blair transport medium (MCB) was evaluated for recovery of Pasteurella spp. from pharyngeal swabs of healthy Rocky Mountain bighorn sheep (Ovis canadensis canadensis). In experiment one, three pharyngeal swabs were collected from each of 25 bighorns. Pasteurella haemolytica was recovered from 21 of 25 swabs tested almost immediately and from 16 of 25 swabs held in MCB medium at about 22 C for 24 hr before testing (P > 0.10). Recovery of P. haemolytica decreased (P < 0.005) to 1 of 25 when swabs were held in MCB medium at about 22 C for 48 hr before testing. In experiment two, four pharyngeal swabs were collected from each of ten bighorns and held in MCB medium at about 5 C for ≤5, 24, 48, or 72 hr prior to testing. Recovery was unaffected by storage at 5 C; P. haemolytica was isolated from all 40 of these samples. All Pasteurella spp. isolates were nonhemolytic P. haemolytica. In experiment one, most isolates were serotype 4; in experiment two, serotype 3 was most common. We propose that...
Science and Security before the Atomic Bomb: The Loyalty Case of Harald U. Sverdrup

Abstract In the summer of 1941, Harald Sverdrup, the Norwegian-born Director of the Scripps Institution of Oceanography (SIO) in La Jolla, California, was denied security clearance to work on Navy-sponsored research in underwater acoustics applied to anti-submarine warfare. The clearance denial embarrassed the world renown oceanographer and Arctic explorer, who repeatedly offered his services to the U.S. government only to see scientists of far lesser reputation called upon to aid the war effort. The official story of Sverdrup's denial was the risk of blackmail over relatives in occupied Norway. Declassified documents tell a different story. Although Sverdrup's integrity was defended on the highest levels of U.S. science, doubt was cast upon him by members of his own institution, who accused him of being a Nazi sympathiser. Personal distrust, rooted in scientific and intellectual disagreement, spilled over into questions about Sverdrup's loyalty and judgement. These doubts were considered sufficient grounds for withholding clearance, until Roger Revelle, a former student of Sverdrup now working within the Navy, was able to obtain a limited clearance for Sverdrup to develop techniques to forecast surf conditions during amphibious assaults. After the war, this work was credited with saving many lives, but at the time it placed Sverdrup out of the mainstream of Navy-sponsored oceanographic research. In being denied access to major areas of scientific work, Sverdrup's position as a leader of American oceanography was undermined. The loyalty case of Harald Sverdrup illustrates the emergence of an institutional apparatus through which the U.S. military began to control and shape the organisation of American science in the twentieth century. Military sponsorship of scientific research, begun during the open conflicts of World War II and continuing into the simmering tensions of the Cold War, involved explicit control by the U.S. military of who had access to critical information. This in turn meant who could do science in conjunction with the military. As the U.S. Navy became the principal sponsor of oceanography in the post-war years, clearance to do military work became to a great extent clearance to do oceanography. Choices about who could be trusted were also choices about who would do science, and what kind of science they would do.
Subpicosecond uv kinetic spectroscopy: Photolysis of thallium halide vapors

Abstract The formation of Tl atoms resulting from subpicosecond UV (308, 248.5 nm) photolysis of TlCl and TlI vapors is probed via subpicosecond UV kinetic absorption spectroscopy. Unusual line shapes are observed for a period lasting roughly 1 ps, from the moment the atomic transition first appears, to the point at which the final, asymptotic, line shape is attained. These spectra are explained in terms of a model based upon the transient behavior of the polarization induced by the probe continuum pulse as it interacts with a growing population of two-level atoms whose resonance frequencies shift in time.
A comparison of the fatigue behavior of human trabecular and cortical bone tissue.

The fatigue properties of trabecular bone tissue (single trabeculae) and similarly sized cortical bone specimens from human tibia were experimentally determined on a microstructural level using four- point bending cyclic tests, and they were compared based on modulus, mineral density, and microstructural characteristics. The results showed that trabecular specimens had significantly lower moduli and lower fatigue strength than cortical specimens, despite their higher mineral density values. Fracture surface and microdamage analyses illustrated different fracture and damage patterns between trabecular and cortical bone tissue, depending upon their microstructural characteristics. Based on the results from mechanical tests and qualitative observations, a possible mechanical role of the cement lines in trabecular tissue micro- fracture was suggested.
Development and Assessment of A Diagnostic Tool to Identify Organic Chemistry Students’ Alternative Conceptions Related to Acid Strength

The central goal of this study was to create a new diagnostic tool to identify organic chemistry students’ alternative conceptions related to acid strength. Twenty years of research on secondary and college students’ conceptions about acids and bases has shown that these important concepts are difficult for students to apply to qualitative problem solving. Yet, few published studies document how students’ prior knowledge of acids influences their understanding of acid strength in organic chemistry contexts. We developed a nine-item multiple-tier, multiple-choice concept inventory to identify alternative conceptions that organic chemistry students hold about acid strength, to determine the prevalence of these conceptions, and to determine how strongly these conceptions bias student reasoning. We identified two significant alternative conceptions that organic chemistry students hold about acid strength. Students who answered items incorrectly were more confident about their answers than peers who answered i...
Diagnostic nuclear medicine in the ED

Although the decision to use nuclear medicine (NM) modalities in the acute care setting is limited by several factors, there are instances in which the use of NM techniques can provide elegant and efficient solutions to otherwise expensive and resource consuming situations. Herein, we describe the indications and NM techniques used for the evaluation of low-risk patients with chest pain, suspected pulmonary embolus, acute cholecystitis, gastrointestinal bleeding, acute scrotum, and the radiographically occult fracture.
Studies on the manganese-mediated isomerization of alkynyl carbonyls to allenyl carbonyls

A study of the role of base in the isomerization of manganese-coordinated conjugated alkynyl carbonyls to the corresponding allenyl carbonyls is described. The use of phosphine additives indicates that manganese requires a ligand prior to isomerization with amine bases. A series of amine bases were also examined for their efficacy in this isomerization reaction revealing a strong dependence on pKa. By contrast, potassium tert-butoxide led to rapid isomerization in the absence of added manganese ligand.
Three-dimensional profiles from residue-pair preferences: identification of sequences with beta/alpha-barrel fold.

Abstract The three-dimensional profile method expresses the three-dimensional structure of a protein as a table, the profile, which represents the local environment of each residue. The score of an amino acid sequence, aligned with the three-dimensional profile, reflects its compatibility with the profiled structure. In the original implementation, each local environment was characterized by its polarity, the area buried of its side chain, and its secondary structure. Here we describe a modified three-dimensional profile algorithm that characterizes the local environment in terms of the statistical preferences of the profiled residue for neighbors of specific residue types, main-chain conformations, or secondary structure. Combined profiles of the original and the three new types were tested on beta/alpha-barrel protein structures. The method identified the following enzymes of unknown three-dimensional structure as probable beta/alpha-barrels, all of which catalyze reactions in the biosynthesis of aromatic amino acids: anthranilate phosphoribosyltransferase (trpD), glutamine amidotransferase (trpG), and phosphoribosylformimino-5-aminoimidazole carboxamide ribotide isomerase (hisA).
Effects of quinacrine on egg activation: a possible role for phospholipase A2 in sea urchin fertilization

Summary The possible role of arachidonic acid and its metabolites in sea urchin egg activation was examined using inhibitors of arachidonic acid release and metabolism. Quinacrine, a phospholipase A2 inhibitor, blocked the cortical granule reaction and inhibited pronuclear migration and cleavage in fertilized eggs. Indomethacin and eicosatetrayenoic acid, blockers of arachidonic acid metabolism, had no affect on these processes. These findings suggest that phospholipase A2 activation may be important in mediating events involving cortical granule exocytosis, pronuclear morphogenesis and mitosis in fertilized sea urchin eggs, perhaps by releasing free arachidonic acid. Subsequent metabolism of arachidonic acid does not seem to be involved in processes of egg activation as inhibitors of arachidonic acid metabolism had no demonstrable effects on fertilization events following egg activation and the cortical granule reaction.
Hematopoietic stem cells and other hematopoietic cells show broad resistance to chemotherapeutic agents in vivo when overexpressing bcl-2

Objective. Chemotherapeutic agents function by inducing apoptosis and their effectiveness depends on the balance of pro- and anti-apoptotic proteins in cells. Due to the complicated interactions of the many proteins involved, it has been difficult to determine in tumors whether overexpression of single genes is prognostic for increased resistance. Therefore, we studied the influence of bcl-2 overexpression on resistance to chemotherapeutics in a transgenic mouse system. This allowed us to study a wide variety of cells, including important but rare populations such as hematopoietic stem cells (HSC).Methods. H2K-bcl-2 transgenic and wild-type (WT) mice were treated with several agents(5-fluoruracil, cyclophosphamide, and busulfan) to determine the contribution of increased amounts of bcl-2 to the response to these chemotherapeutics in vivo. Populations were enumerated using flow cytometry. HSC were studied by FACS purification and long-term reconstitution assays in vivo and resistance was confirmed by short-term proliferation assays with different amounts of chemotherapeutics in vitro.Results. bcl-2 overexpression alone protects many cell types, though protection levels differ between populations and agents. However, even sensitive populations return to pretreatment levels faster in transgenic mice. bcl-2 overexpression also prevents the dramatic changes in HSC following 5-FU treatment (downregulation of c-kit, upregulation of Lin, less efficient long-term reconstitution). In vitro studies directly demonstrate increased resistance of bcl-2 overexpressing HSC to chemotherapeutic agents.Conclusions. Increased expression of bcl-2 in HSC and their progeny endows these cells with broad resistance to chemotherapeutic agents. The ability to (differentially) regulate sensitivity to apoptosis of bystander and tumor cells is clinically important.
Pulsatile Luteinizing Hormone Amplitude and Progesterone Metabolite Excretion Are Reduced in Obese Women

Context: Female obesity is linked to abnormal menstrual cycles, infertility, reproductive wastage, and deficient LH, FSH, and progesterone secretion. Objective and Design: To elucidate the reproductive defects associated with obesity, we sampled 18 eumenorrheic (nonpolycystic ovary syndrome) women with a mean ± sem body mass index of 48.6 ± 1.4 kg/m2 with daily, first morning voided urine collections, seven of whom also had early follicular phase 12-h, every 10-min blood sampling to assess LH pulses. Daily hormones were compared with 11 eumenorrheic, normal-weight controls. A separate control group of 12 eumenorrheic, normal-weight women was used for the LH pulse studies. Main Outcome Measures: Assays for LH (serum and urine) and FSH, and estradiol and progesterone metabolites (estrone conjugate and pregnanediol glucuronide; urine) were performed. Daily hormones were meaned and normalized to a 28-d cycle length. LH pulsations were determined using two objective methods. Group means were compared using t t...
Singularity theory and configuration space models of ωnSn of non-connected spaces

Abstract We consider the bordism theory generated by quadruples (Mk,f,X;g) where Mk is an oriented smooth manifold ƒ:M k →X is a map, and g:Mk→Rk is a smooth map exhibiting only the simplest, i.e. fold, singularities. We show this theory represents the unreduced stable homotopy of X, and we give a variant representing the groups πkωnSn(X) for Sn(X) the unreduced suspension of X. We interpret these results as giving a sub-space ωnPSn(X) of ωnSn(X) with the inclusion ωnPSn(X)→ωnsn(X) a natural weak equivalence. We then give configuration space models Fn(X) and a natural weak equivalence ϕn:Fn(X)→ωnPSn(X). Finally we give a category theoretic model for the functor Fn( ). This allows us to interpret the previous results as a geometric proof of the Barratt-Priddy-Quillen equivalence ω∞S∞(x)→ BS(∞)+×Z, and as an unstable, functorial geometric version of this equivalence.
Lymphotoxin beta-mediated stimulation of synoviocytes in rheumatoid arthritis.

Objective Lymphotoxin β (LTβ), a cytokine produced by T cells and B cells, plays a central role in the normal development of lymph nodes and is critical in the formation of ectopic germinal center reactions in rheumatoid synovitis. Because resident fibroblast-like synoviocytes (FLS) express receptors for LTβ, we examined the consequences of FLS activation by LTβ. Methods FLS from patients with rheumatoid arthritis were isolated and examined for the expression of LTβ receptor. FLS were incubated with LTα1β2 and assayed for the production of cytokines and chemokines and the up-regulation of adhesion molecules. Results Exposure of FLS to recombinant LTα1β2 resulted in the production of multiple inflammatory cytokines and metalloproteinases, implicating FLS as amplifiers of the inflammatory process in the inflamed joint. Additionally, LTα1β2 was found to up-regulate the expression of cell adhesion molecules, rendering FLS to efficient adhesion substrates for T cells. LTα1β2 also induced production of the chemokines CCL2 and CCL5, which elicited transmigration activity of T cells. Upon stimulation with LTα1β2, FLS did not acquire characteristics of follicular dendritic cells. Conclusion These data document that FLS are involved in multiple stages of the inflammatory process, including the recruitment and retention of lymphocytes in the synovial microenvironment. We propose that the heterotypic interaction between LTβ-producing lymphocytes and responding FLS contributes to the establishment of complex lymphoid microstructures, and that this may be one element that defines susceptibility of the synovial membrane to lymphoid organogenesis.
Fusions of Character Tables II: p-Groups

If the character table of a finite group H satisfies certain conditions, then the classes and characters of H can fuse to give the character table of a group G of the same order. We investigate the case where H is an abelian group. In a previous article, we gave examples of Camina pairs that fuse from abelian groups. In this article, we give more general examples of Camina triples that fuse from abelian groups. We use this result to give an example of a group which fuses from an abelian group, but which has a subgroup that does not. We also give an example of a powerful 2-group which does not fuse from an abelian group and of a regular 3-group which does not fuse from an abelian group.
Interrogating biology with a chemical lexicon.

Understanding the mysteries of life has always been a driving force in scientific research; Barbara Imperiali from the Massachusetts Institute of Technology reflects on the infinite opportunities for chemists at the biology interface.
Hydration, dynamics, and transport across the phase diagram of aqueous poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (Pluronic L64) by spin probe electron spin resonance and electron spin resonance imaging

The aggregation of the triblock copolymer poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (EO13PO30EO13; commercial name Pluronic L64) in aqueous solutions and the hydration of the PEO blocks were deduced from ESR spectra of the nitroxide spin probe perdeuterio-2,2‘,6,6‘-tetramethylpiperidone N-oxide in the temperature range 293−330 K. The isotropic 14N hyperfine splitting of the nitroxide, aN, is a key parameter that reflects the local polarity, and its variation with temperature and polymer concentration is an indicator of aggregation. The effective hydration of the polymer chains was determined by comparison of aN values of the probe across the phase diagram with “calibration” curves of aN in pure PEO, pure PPO, and mixtures of the homopolymers, measured as a function of the water content Zw, where Zw is the number of water molecules per monomer unit. The calibration curves indicated that the spin probe is preferentially located in the vicinity of the EO segments and reports on the ...
Chaotic time series prediction for the game, Rock-Paper-Scissors

Two players of Rock-Paper-Scissors are modeled as adaptive agents which use a reinforcement learning algorithm and exhibit chaotic behavior in terms of trajectories of probability in mixed strategies space. This paper demonstrates that an external super-agent can exploit the behavior of the other players to predict favorable moments to play against one of the other players the symbol suggested by a sub-optimal strategy. This third agent does not affect the learning process of the other two players, whose only goal is to beat each other. The choice of the best moment to play is based on a threshold associated with the Local Lyapunov Exponent or the Entropy, each computed by using the time series of symbols played by one of the other players. A method for automatically adapting such a threshold is presented and evaluated. The results show that these techniques can be used effectively by a super-agent in a game involving adaptive agents that exhibit collective chaotic behavior.
Technical Note---Stochastic Sequential Decision-Making with a Random Number of Jobs

This paper addresses a class of problems in which available resources need to be optimally allocated to a random number of jobs with stochastic parameters. Optimal policies are presented for variations of the sequential stochastic assignment problem and the dynamic stochastic knapsack problem, in which the number of arriving jobs is unknown until after the final arrival, and the job parameters are assumed to be independent but not identically distributed random variables.
How Constructivist-Based Teaching Influences Students Learning Science.

Abstract The purpose of this article is to provide details about the beneficial processes the constructivist pedagogy has in the area of teaching science. No Child Left Behind could possibly cause detrimental effects to the science classroom and the constructivist teacher, so this essay tells how constructivist-based teaching influences students and their learning of science.
T-Tubule Remodeling Causes Ca2+ Cycling Defects during the Progression to Heart Failure in the Intact Spontaneously Hypertensive Rat Heart

Severe disruption of the t-tubule network in cardiac myocytes has been found in nearly all animal and human models of heart failure. T-tubule disorganization would be expected to cause alterations in the EC coupling because of a separation of junctional SR from trigger Ca entry and the increase in orphaned ryanodine receptors. However, little is currently known about changes in t-tubules during the early stages of disease development, before heart failure (HF) develops. The goal of this study was to measure the relationship between cardiac function, t-tubule organization and Ca2+ cycling defects in whole hearts during the progression to HF. We combined echocardiography with confocal measurements of t-tubule organization (di-4-ANEPPS) and Ca2+ (fluo-4AM) in intact hearts of spontaneously hypertensive rats (SHR) ranging from 4 to 18 months of age. Echocardiography demonstrated defects in cardiac function that correlated with an increasing number of myocytes showing decreased t-tubule organization (calculated from FFTs of confocal images). In addition, t-tubule disorganization caused progressive development of Ca2+ cycling defects, explaining the reduced overall cardiac function. Our data suggest that the progression from hypertension to HF in SHRs occurs as the number of myocytes showing poor t-tubule organization and Ca2+ cycling defects increases and the fraction of normal cells decreases.
The c-erbB transmembrane growth factor receptors as serum biomarkers in human cancer studies

Over-expression of the transmembrane growth factor receptors encoded by the c-erbB oncogenes contributes to cellular transformation in model systems and is found to be a frequent occurrence in human tumors. Over-expression of these receptors results in accumulation of the extra-cellular domain in the extra-cellular supernatant in vitro and in elevated levels of the extra-cellular domain in serum in vivo in animal models. Similarly, elevated levels of the extra-cellular domain of these receptors have been detected in the serum of individuals with various cancers, including of the breast, ovary, prostate, stomach, pancreas, colon, liver, and lung. In some cases, elevated serum levels have been detectable prior to the time of clinical diagnosis of disease. Thus, the serum levels of the extra-cellular domains of the c-erbB transmembrane growth factor receptors may be useful biomarkers of carcinogenesis in human studies.
Graph algorithms on a tree-structured parallel computer

Parallel algorithms for some graph-theoretic problems on a tree-structured computer are presented. In particular, ifp denotes the number of processing elements, algorithms that run inO(n2/p) time for finding connected components, transitive closure and the minimum spanning tree of an undirected graph withn vertices are obtained.
The association between microtubules and nuclei during spermiogenesis in the dragonfly

Electron microscope studies on dragonfly spermatids at different stages during their maturation into spermatozoa reveal the nucleus (in transverse section) to be folded, resulting in a number of alternate furrows and ridges. During the elongation of the sperm head, the furrows become deeper and the chromatin of the nucleus is compressed or condensed. The specific orientation of groups of microtubules abotu 250 A in diameter in these furrows throughout spermiogenesis is suggestive that they play a role in the elongation of the nucleus. Microtubules are no longer associated with the nuclei of mature sperm. Microtubules are also associated with elements of the mid-piece and with each of the peripheral filaments in the flagellum.
Automatic unstructured grid generators

Abstract A review of automatic unstructured grid generators is given. These types of grids have found widespread use in computational fluid dynamics, computational structural dynamics, computational electro-magnetics and computational thermodynamics. The following topics are treated: the methods most commonly used, the specification of desired element size/shape and surface definition/meshing. Finally, the use of automatic grid generators as an enabling technology for moving body simulations and adaptive remeshing techniques is discussed.
Sensitivity of self-report mammography use in older women.

Background Recent survey evidence indicates a decline in mammography use among older women. Purpose The objective of this study was to detect sensitivity of self-reported mammography use and pose evidence-based suggestions to increase survey accuracy. Methods Using the 1991–2006 Medicare Current Beneficiary Survey, 15,357 women, aged ≥65 years, were selected based on use of mammography services. The women were interviewed in the community setting at random periods after screening and asked, Have you had a mammogram or breast X-ray since [today's date or previous supplement round interview date] a year ago? Statistical analyses were conducted between March 11 and April 28 of 2008. This study tested whether sensitivity (i.e., probability of an affirmative response) was dependent on length of the recall period and on respondent demographic and socioeconomic characteristics. Results Overall, 90.4% of the older women self-reported use; however, sensitivity decreased as the recall period lengthened (90% at 6 months, 80% at 12 months). This time effect was significantly higher among older, economically disadvantaged women. Sensitivity also decreased an additional 13.8% if the event occurred in the previous calendar year, and 3.5% if conducted in a non-English language or by proxy. Conclusions Greatest sensitivity occurred during the 6-month period after service without straddling calendar years. These findings may aid the tailoring of future surveys for older adults, improving the recall of preventive services.
A Total Evidence Phylogeny of the Arctoidea (Carnivora: Mammalia): Relationships Among Basal Taxa

A total evidence phylogenetic analysis was performed for 14 extant and 18 fossil caniform genera using a data matrix of 5.6 kbp of concatenated sequence data from six independent loci and 80 morphological characters from the cranium and dentition. Maximum parsimony analysis recovered a single most parsimonious cladogram (MPC). The topology of the extant taxa in the MPC agreed with previous molecular phylogenies. Phylogenetic positions for fossil taxa indicate that several taxa previously described as early members of extant families (e.g., Bathygale and Plesictis) are likely stem taxa at the base of the Arctoidea. Taxa in the “Paleomustelidae” were found to be paraphyletic, but a monophyletic Oligobuninae was recovered within this set of taxa. This clade was closely related to the extant genera Gulo and Martes, therefore, nested within the extant radiation of the family Mustelidae. This analysis provides a resolution to several discrepancies between phylogenies considering either fossil taxa or extant taxa separately, and provides a framework for incorporating fossil and extant taxa into comprehensive combined evidence analyses.