cssi/SciSciGPT-SciSciNet huggingface dataset:
Static contraction causes a reflex-induced release of arginine vasopressin in anesthetized cats.

We tested the hypothesis that brief static contraction of the triceps surae muscle causes reflex-induced increases in plasma arginine vasopressin (AVP) in anesthetized cats. Arterial blood samples, for measurement of plasma AVP, were taken before and after 30 s of electrically stimulated static contraction performed at a low intensity ( 70% of maximal; n = 7), and a high intensity after denervation of the triceps surae (n = 5). The low intensity contraction protocol was repeated during α-adrenergic blockade (n = 7) to minimize potential baroreflex-induced inhibition of AVP release. Passive stretch of the triceps surae was conducted (n = 5) to determine effects of muscle mechanoreceptor stimulation on the release of AVP. Low intensity contraction had no effect on plasma AVP. During α-adrenergic blockade, this same contraction intensity caused this peptide to increase from12.8 ± 2.1 to 17.7 ± 2.6 pg/ml. High intensity contraction caused an increase in AVP (13.2 ± 3.5 to 26.1 ± 6.6 pg/ml) that was abolished by denervation (14.4 ± 3.7 vs. 17.1 ± 6.6 pg/ml). Passive stretch had no effect on plasma AVP. These findings suggest that brief static contraction causes increases in plasma AVP that are reflex in nature, intensity dependent, opposed by the arterial baroreflex, and probably unrelated to muscle mechanoreceptor activation.
Synthesis and coordination properties of new bis(phosphinomethyl)pyridine N,P,P'-trioxides.

In a search for more hydrocarbon solvent soluble derivatives of the parent ligand, 2,6-[Ph2P(O)CH2]2C5H3NO (1a), a series of new ligands, 2,6-[R2P(O)CH2]2C5H3NO [R = Bz (1b); Tol (1c); Et (1d); Pr (1e); Bu (1f); Pn (1g); Hx (1h); Hp (1i); and Oct (1j)] and 2,6-[RR‘P(O)CH2]2C5H3NO [R = Ph, R‘ = Bz (2a); R = Ph, R‘ = Me (2b); R = Ph, R‘ = Hx (2c); R = Ph, R‘ = Oct (2d)], have been prepared by either Arbusov or Grignard substitutions on 2,6-bis(chloromethyl)pyridine followed by N-oxidation. The new ligands have been characterized by spectroscopic methods, and their coordination chemistry with selected lanthanide ions has been surveyed. Several 1:1 and 2:1 ligand/metal complexes have been isolated, and single-crystal X-ray diffraction analyses for Nd(2a)(NO3)3, Er(2a)(NO3)3, Yb(1d)(NO3)3, and [Nd(1c)2](NO3)3 are described. The new structural data are discussed in relation to the structures of complexes formed by 1a.
Crystallization and preliminary X-ray diffraction data for the cyclic AMP receptor protein of Escherichia coli.

Abstract The cyclic AMP receptor protein (CRP) of Escherichia coli has been crystallized. The crystals are orthorhombic, space group P2 1 2 1 2 1 , a = 46.5 A , b = 97.1 A, c = 105.4 A , with one dimeric CRP molecule per asymmetric unit.
Relaxation properties of two-level systems in condensed phases

Abstract The equation of motion for the reduced density matrix of a system weakly coupled to a bath is obtained using projection operator techniques. The exact equation of motion reduces to a generalized master equation when the bath relaxation is faster than the relaxation of the system induced by the weak interaction with the bath. The equation separates into streaming or systematic terms and dissipative terms which are separately equal to zero at equilibrium. We find both statistical and dynamical system frequency shifts; the statistical shifts are present in equilibrium but the dynamical shifts affect the time-dependence, only. The general results are applied to the two-level system model for tunneling in condensed phases.
Evaluation of the microcirculation: advances in cardiac magnetic resonance perfusion imaging.

In this review we have examined the role of perfusion CMR for evaluating the integrity and function of the microcirculation. We have discussed the techniques for fully quantifying myocardial blood flow and the impact of different imaging parameters on quantification. Perfusion CMR not only identifies the presence of microvascular obstruction after a myocardial infarction but also relates it to patient prognosis. The ability to absolutely quantify myocardial blood flow improves the detection and evaluation of epicardial coronary disease and its risk factors. CMR perfusion imaging has proved to be an invaluable tool for understanding the integral role of the microcirculation in a variety of other cardiac disorders. Another advantage of perfusion CMR is the ability to measure differences in subendocardial and subepicardial blood flow. Newer techniques such as ASL and BOLD imaging promise to further improve the ability of CMR to assess the microcirculation without the use of exogenous contrast agents.
On the rigidity of the North American plate

Abstract Recently reported Very Long Baseline Interferometer (VLBI) observations between Green Bank, West Virginia, Haystack, Massachusetts and Owens Valley, California, show that the linear distance between these sites has not changed for at least three years (i.e., smooth rate of change less than 1 cm/yr). This level of stability is logically consistent with the hypothesis that the continental U.S. North American plate is geodetically rigid at least on the 2 cm level. Model studies show that this result is in accord with present knowledge of the intra-plate stress field and the elastic properties of typical continental lithosphere.
Signaling From the Podocyte Intercellular Junction to the Actin Cytoskeleton

Observations of hereditary glomerular disease support the contention that podocyte intercellular junction proteins are essential for junction formation and maintenance. Genetic deletion of most of these podocyte intercellular junction proteins results in foot process effacement and proteinuria. This review focuses on the current understanding of molecular mechanisms by which podocyte intercellular junction proteins such as the nephrin-neph1-podocin-receptor complex coordinate cytoskeletal dynamics and thus intercellular junction formation, maintenance, and injury-dependent remodeling.
Two-dimensional lateral bipolar transistor model for circuit simulation

A lateral bipolar transistor circuit model including two-dimensional current characteristics has been developed. The model accounts for the physical effects of base width modulation, base conductivity modulation, hole-electron plasma-induced bandgap narrowing, and current-dependent base resistance. SPICE simulation employing the present model shows good agreement with computer experimental results.
Polarity of hepatic glutathione and glutathione S-conjugate efflux, and intraorgan mercapturic acid formation in the skate

Abstract Mechanisms of hepatic glutathione and glutathione S -conjugate efflux were investigated in isolated hepatocytes and perfused liver of the little skate ( Raja erinacea ). Glutathione was released by isolated skate hepatocytes at a rate of 0.12 ± 0.03 nmol · hr −1 · (mg protein) −1 . In the perfused liver, glutathione concentrations in bile were high (∼0.7mM) compared to hepatic tissue levels (0.61 ± 0.11 μ mol · g −1 ). During the first hour of perfusion, the biliary glutathione excretion rate was 3 nmol · hr −1 · (g liver) −1 , whereas glutathione accumulated in the recirculating perfusate at a rate of only 1.5nmol · hr −1 · (g liver) −1 . Release of glutathione by isolated hepatocytes and perfused liver was not affected by the addition of acivicin, an inhibitor of γ-glutamyltransferase (EC 2.3.2.2), to cell suspension medium or liver perfusate. 1-Chloro-2,4-dinitrobenzene (CDNB) was taken up by isolated hepatocytes, conjugated to glutathione, and released as 5-(2,4-dinitrophenyl) (DNP)-glutathione. After infusion of 0.5 μmol CDNB in perfused liver, S -DNP-glutathione was concentrated in bile (0.5 mM) and was associated with choleresis. S -DNP-Conjugates of cysteinylglycine, cysteine and N -acetylcysteine, were also found in bile, suggesting intrahepatic breakdown of S -DNP-glutathione and subsequent acetylation of the resulting cysteine conjugate to form the mercapturic acid, S -DNP- N -acetylcysteine. This mercapturic acid accounted for 31% of the total S -DNP-conjugates collected in bile. In contrast, neither S -DNP-glutathione nor other S -DNP-conjugates were detected in the perfusate ( S -conjugate from skate liver. The results also identify an intrahepatic pathway for mercapturic acid biosynthesis facilitated by biliary glutathione S -conjugate excretion.
Nanotechnology research directions for societal needs in 2020: summary of international study

The paper examines the progress made in nanotechnology development since 2000, achievements at ten years, and opportunities in research, education, innovation and societal outcomes by 2020 worldwide.
Firm-level technological capability assessment; a literature review

That would be very hard to find a strategic planning model which is not taking capabilities of the firm into account at least in some degree. Results of this capability assessment, combining to inputs of market analysis, would form future strategies of the firm. Some of the theories like resource-based theories or dynamic capabilities theories have more emphasize on the firm's capabilities, while in other views such as Porter's 5-forces model, still capabilities are key parts of decision making and strategy planning process. But when it reaches to the assessment of the capabilities of a firm, barely a clear and comprehensive model could be found. This study aims to search around all the existing technological capabilities assessment (TCA) models, and find out each-one's pros and cons.
Involvement of hypoxia-inducible factor 1 in human cancer.

Hypoxia-inducible factor 1 (HIF-1) mediates transcriptional responses to hypoxia. HIF-1 is composed of an O2-and growth factor-regulated HIF-1α subunit and a constitutively-expressed HIF-1β subunit. Four lines of evidence indicate that HIF-1 contributes to tumor progression. First, HIF-1 controls the expression of gene products that stimulate angiogenesis, such as vascular endothelial growth factor, and promote metabolic adaptation to hypoxia, such as glucose transporters and glycolytic enzymes, thus providing a molecular basis for involvement of HIF-1 in tumor growth and angiogenesis. Second, in mouse xenograft models, tumor growth and angiogenesis are inhibited by loss of HIF-1 activity and stimulated by HIF-1α overexpression. Third, immunohistochemical analyses of human tumor biopsies indicate that HIF-1α is overexpressed in common cancers and that the level of expression is correlated with tumor grade, angiogenesis, and mortality. Fourth, in addition to intratumoral hypoxia, genetic alterations in tumor suppressor genes and oncogenes induce HIF-1 activity.(Internal Medicine 41: 79-83, 2002)
A web implementation: the good and the not-so-good.

E-commerce, e-mail, e-greeting, e-this, and e-thate-verywhere you turn there is a new “e” word for an internet or Web application. We, at the Cleveland Clinic Foundation, have been “e-nlightened” and will discuss in this report the implementation of a webbased radiology information system (RIS) in our radiology division or “e-radiology” division. The application, IDXRad Version 10.0 from IDX Corp, Burlington, VT, is in use at the Cleveland Clinic Foundation and has both intranet (for use in Radiology) and internet (referring physician viewing) modules. We will concentrate on the features of using a web browser for the application’s front-end, including easy prototyping for screen review, easier mock-ups of demonstrations by vendors and developers, and easier training as more people become web-addicted. Project communication can be facilitated with an internal project web page, and use of the web browser can accommodate quicker turnaround of software upgrades as the software code is centrally located. Compared with other technologies, including client/server, there is a smaller roll out cost when using a standard web browser. However, the new technology requires a change and changes are never implemented without challenges. A seasoned technologist using a legacy system can enter data quicker using function keys than using a graphical user interface and pointing and clicking through a series of pop-up windows. Also, effective use of a web browser depends on intuitive design for it to be easily implemented and accepted by the user. Some software packages will not work on both of the popular web browsers and then are tailored to specific release levels. As computer-based patient records become a standard, patient confidentiality must be enforced. The technical design and application security features that support the webbased software package will be discussed. Also web technologies have their own implementation issues. Copyright© 2001 by W.B. Saunders Company
Cosmic-ray tracks in plastics: the apollo helmet dosimetry experiment.

Heavy cosmic ray nuclei track counts in plastics, examining Apollo mission 8 and 12 helmets
Treatment of aplastic anemia with an investigational antilymphocyte serum prepared in rabbits.

ABSTRACT The authors evaluated antilymphocyte serum prepared in rabbits (ALS-R) as an alternative to antilymphocyte serum prepared in horses (ALG-H) in the therapy of aplastic anemia. Between 1980 and 1993, 57 evaluable patients received ALS-R and prednisone ± cyclosporin ± androgens. Standard response criteria were used and patients were evaluated at 3 months from the start of therapy. Median age was 43 years. Disease was present for up to 2 months in 24 patients, 2–5 months in 14 patients, and 6 months or more in 19 patients. Disease was severe in 30 patients and moderate in 27. Responses occurred in 16 (28%) of 57 patients. Responses were more frequent in females, in patients treated within 6 months of diagnosis, and in patients with severe disease. Among patients receiving ALS-R and cyclosporine within 2 months of diagnosis, 46% responded. After ALS-R therapy, 20 patients received ALG-H; 8 (40%) of 20 responded. Eight patients receiving ALS-R previously had received ALG-H; 2 (25%) of these 8 patients responded. Toxicity of ALS-R was minimal. Antilymphocyte serum prepared in rabbits, in conjunction with other immunosuppressive agents, represents an effective alternative to ALG-H in aplastic anemia, especially in patients previously treated with ALG-H.
NEUROPHYSICAL MATURATION IN IDM: EFFECT OF EARLY MATERNAL MANAGEMENT

Although diabetes in pregnancy is thought to delay maturation of fetuses, its effects on neurophysical maturation have not been examined, especially in regard to the time of initiation of diabetic management. We tested the hypothesis that the diabetic intrauterine environment will retard the rate of fetal neurophysical maturation and that institution of maternal metabolic control before 9 wks of pregnancy (early) will reduce the maturation delay. Gestation was assessed in 104 infants of insulin dependent diabetic mothers (IDM) followed prospectively and in 221 infants of non-diabetic mothers (non-IDM), by standard clinical exam (Ballard, J. et al, 1979). Both groups had reliable obstetrically confirmed menstrual dates. At all gestations neurophysical maturity was advanced by 0.6 weeks in IDM when compared with non-IDM (p=0.005). Early institution of diabetic management in pregnancy (n=76) vs later (n=28) was not associated with change in rate of maturation. In the IDM group there was no effect of race, sex, or tobacco, alcohol, or coffee consumption on maturation. Lack of clinical RDS was associated with accelerated neurophysical maturation (p<0.003). We conclude that the diabetic intrauterine environment has an accelerating rather than retarding effect on gestational neuro-physical maturation; early institution of diabetic management does not affect the rate of intrauterine maturation.
Surface evolution of crystalline tubes: effect of lattice diffusion

The surface evolution of an annular tube has been established on the basis of lattice diffusion and linear stability analysis. Without surface disturbance, the annular tube shrinks to reduce the surface energy while the cross-sectional area of the tube remains constant. For an annular tube having infinitesimal thickness, the time dependence of the tube radius follows a linear law. When surface energy is significant, a new dispersion relation describing the morphological stability of crystalline tubes due to longitudinal surface perturbation has been formulated. A criterion has been obtained on the dependence of perturbation growth rate on perturbation frequency. The perturbation will grow when the perturbation frequency is less than the critical frequency, which is equal to the inverse of the inner surface radius. The surface instability leads to the formation of closed end of crystalline tubes.
Anterior Perineal Reconstruction in Exstrophy-epispadias Complex

Abstract Objectives: To assess the role of correct anatomical reconfiguration of the anterior perineal musculature in exstrophy-epispadias (E-E) patients. To stress the use of a bipolar stimulator to detect the perineal muscular complex intraoperatively, and to increase the functional results of reconstruction in E-E patients. Methods: A total of 22 patients with E-E complex were treated in a 7-year period: 17 patients presenting classic bladder extrophy (aged 3 days to 6 years) and 5 incontinent male epispadias (aged 9 months to 16 years). An electric bipolar stimulator was used to identify and reapproximate at the midline the muscular fibers that constitute the periurethral muscular complex, as a part of the anterior perineal membrane. Outcome was evaluated at 24 months from surgery, considering bladder capacity, dry intervals, urinary infections (UTI's), upper tract deterioration and surgical complications (fistula, obstruction, dehiscence). Results were compared with a matched group of 19 E-E patients treated in the previous 5-year period, without the presented technique (control group). Student T -test was used for statistical analysis, considering p ≤0.05 as significant. Results: No bladder neck or urethral dehiscence was observed. Mean bladder capacity at 2-year follow-up was 80 cc in the exstrophic patients and 120 cc in the male epispadias. Mean dry interval increased to 75minutes in the exstrophy patients and to 130minutes in the male epispadias. Full daytime continence was achieved in 3 exstrophic and in all the epispadic patients. The difference with the control group of patients was significant ( p Conclusions: Proper identification of the anterior perineal muscular complex, using a bipolar stimulator, and its reapproximation at the posterior urethra on the midline was demonstrated to be effective in increasing bladder cycling and in developing adequate bladder volume, anticipating coordinated micturition.
Relationship between the expressive one‐word picture vocabulary test and measures of intelligence, receptive vocabulary, and visual‐motor coordination in borderline and mildly retarded children

Analysis of the relationship between the Expressive One-Word Picture Vocabulary Test and Stanford-Binet Intelligence Scale, Peabody Picture Vocabulary Test, Developmental Test of Visual-Motor Integration, and three language subscales within the Stanford-Binet was performed on a sample of preschool children within the borderline and mildly retarded ranges of intelligence. Adequate convergent and discriminant validity indices were found to support tentatively the use of the Expressive One-Word Test as one measure of verbal intelligence with this population.
The multichannel log-derivative method for scattering calculations

A new method for solving multichannel scattering problems is presented. The key to the method is an efficient algorithm for numerically solving the matrix Ricatti equation for the logarithmic derivative of the wave function. Previous calculalions on He/sup +/-Ne collision at 70.9 eV were repeated. (JFP)
Expanding graphs contain all small trees

The assertion of the title is formulated and proved. The result is then used to construct graphs with a linear number of edges that, even after the deletion of almost all of their edges or almost all of their vertices, continue to contain all small trees.
Effects of intrauterine inflammation on developing rat brain

Damage to the white matter in the brain during development can lead to cerebral palsy (CP), a heterogeneous group of clinical syndromes that results in life-long disorders of movement and posture. Periventricular leukomalacia (PVL) is a pathological process within the white matter characterized by oligodendrocyte loss and is associated with the development of CP. Clinically, CP and PVL are associated with intrauterine infection and inflammation, but mechanisms involved are not well understood. We developed a model of intrauterine inflammation in Lewis and Fischer 344 rats to study the effects of intrauterine inflammation on developing glia. Pregnant rats were intracervically injected with lipopolysaccharide (LPS) at 15 days of gestation (E15) and a dose of LPS that caused low fetal mortality was determined. At E20, treated fetuses had increased TUNEL+ nuclei and tumor necrosis factor (TNF)-α-immunoreactive areas within the brains. In a second series of animals allowed to survive until postnatal day 21 (PND 21), immunostaining was performed against several glial markers. Staining for the oligodendrocyte-specific proteins 2′, 3′-cyclic nucleotide phosphodiesterase (CNP) and myelin proteolipid protein (PLP) was decreased in treated pups compared to shams within the corpus callosum, a white matter structure used as a representative area of developing white matter. Treated pups had activated astrocytes lining cerebral blood vessels, as observed by glial fibrillary acidic protein (GFAP) staining, while sham pups did not. Activated microglia were not detected using OX42 as a cell marker. Our model of intrauterine inflammation causes increased TUNEL and TNF-α staining early after injury, suggesting increased apoptotic cell death, possibly by cytokine-related mechanisms. © 2002 Wiley-Liss, Inc.
The Case Against Fiduciary Media: Ethics is the Key

Salerno (http://mises.org/daily/4389, 2010a) asserts that in the debate between those who favor and oppose fractional reserve banking, the important issue is not whether or not this institution is inherently fraudulent, but, rather, does it or does it not cause the business cycle. We join this author in thinking both important; however, we reverse this order.
Reading Instruction Grouping for Students with Reading Difficulties

The effects of three grouping formats—1:1 (one teacher with 1 student), 1:3 (one teacher with 3 students), and 1:10 (one teacher with 10 students)—on the reading outcomes of second-grade struggling readers was studied. Students in all groups were given the same supplemental reading intervention for the same number of sessions, thus holding intervention type and intensity constant and varying group size. Students made significant gains in phoneme segmentation, fluency, and comprehension following the intervention, and these gains were maintained at follow-up (4—5 weeks after intervention). Based on effect sizes, both 1:1 and 1:3 were highly effective intervention group sizes for supplemental reading instruction. Although the 1:1 grouping format yielded significantly higher scores for phoneme segmentation, fluency, and comprehension than the 1:10, it was not superior to the 1:3 on any outcome measure.
Secondary production of Chironomidae (Diptera) in a north temperate stream

SUMMARY 1. Secondary production of chironomids (Diptera: Chironomidae) in a third-order northern Indiana stream was estimated using species-specific, and in most cases cohort-specific, life-history data from the field. 2. Chironomid life-history patterns were diverse, ranging from one to four generations per year in addition to asynchronous development. Cohort production intervals (CPI) for all taxa ranged from 56 to 266 days. CPI for cohorts of conspecifics differed up to 3-fold. 3. Annual secondary production was estimated using the instantaneous growth method or the size—frequency method depending on whether cohorts were distinguishable or not. Total annual chironomid production was 29 700 mg dry mass m−2, which is the highest value reported for chironomids from a north temperate stream. 4. Eighty per cent of the total chironomid production was attributed to five species: Diamesa nivoriunda (33.9%), Cricotopus bicinctus (16.6%), Pagastia sp. (10.2%), C. trifascia (9.7%) and Orthodadius obumbratus (9.6%). 5. The annual P:B ratio ranged from 4.7 to 21.9. Thus, high secondary production was due to high mean annual standing stocks and not to rapid biomass turnover.
Aligning Forces For Quality: A Program To Improve Health And Health Care In Communities Across The United States

The Robert Wood Johnson Foundation’s Aligning Forces for Quality program features partnerships with leaders in targeted communities. The program is working to achieve dramatic, sustainable improvements in quality across the continuum of care by 2015. These improvements will affect patients of all races and ethnicities.
Cone-Beam CT Diagnostic Applications: Caries, Periodontal Bone Assessment, and Endodontic Applications

Cone-beam CT (CBCT) is useful for many maxillofacial applications, such as implant site imaging and diagnosis and treatment planning for orthodontics and craniofacial surgery. Dentoalveolar applications, such as carious lesion detection and characterization, assessment of the three-dimensional nature of periodontal bone topography, and various endodontic applications are less known and not as thoroughly studied. This article explores and assesses in vivo and in vitro efforts to apply CBCT imaging to these more common dentoalveolar tasks. CBCT imaging, like its medical counterpart, can be seen as a highly useful and, in some instances, indispensable part of the dental imaging armamentarium.
Properties of ‘Swelling’ Chlorite in Some Mesozoic Formations of California

Abstrac~Slaty strata and their weathering products comprise a large portion of the geologic formations of the western foothills in the Sierra Nevada, Mid-Northern California. The weathering products of Mesozoic slates in particular, locally known as 'swelling' chlorites, have caused numerous problems in road construction. A typical stratigraphic section of slates, which includes 'swelling' chlorites, is given for the area of Chili Bar, California, as part of the general geology of the western foothill formations. Remolded slate densities were observed to decrease while measured swelling pressures increased with increasing slate alteration. Swelling pressures in excess of 12.5 psi were observed. Curves are presented in comparison with DTA results showing the effect of alteration on the slate. The results of X-ray diffraction analyses, in correlation with i.r. data, show a typical slate mineral composition for unaltered material of about one-half chlorite with the remainder being about equal portions of muscovite and quartz. The entire chlorite content of the altered slate becomes a regular mixed-layer clay mineral, corrensite, which has been observed to alter to sedimentary vermiculite and M~saponite in residual soil. An i.r. absorption peak at 3690 cm 1 characterizes the mixed-layer clay mineral. Heat treatment of the mixed-layer clay mineral structure reduces the 14.3 A basal spacing to 11.8 A at 540~ which decreases to 10.6 ~ at 850~ disappearing by 1050~ Procedures are given for direct quantitative analysis of these three-phase mineral systems using simultaneous linear equations. Evidence is presented for the alteration minerals formed during weathering of the slate, including Fourier analysis of the mixed-layer clay structure.
Using quantum mechanics to improve estimates of amino acid side chain rotamer energies.

Amino acid side chains adopt a discrete set of favorable conformations typically referred to as rotamers. The relative energies of rotamers partially determine which side chain conformations are more often observed in protein structures and accurate estimates of these energies are important for predicting protein structure and designing new proteins. Protein modelers typically calculate side chain rotamer energies by using molecular mechanics (MM) potentials or by converting rotamer probabilities from the protein database (PDB) into relative free energies. One limitation of the knowledge-based energies is that rotamer preferences observed in the PDB can reflect internal side chain energies as well as longer-range interactions with the rest of the protein. Here, we test an alternative approach for calculating rotamer energies. We use three different quantum mechanics (QM) methods (second order Moller-Plesset (MP2), density functional theory (DFT) energy calculation using the B3LYP functional, and Hartree-Fock) to calculate the energy of amino acid rotamers in a dipeptide model system, and then use these pre-calculated values in side chain placement simulations. Energies were calculated for over 36,000 different conformations of leucine, isoleucine, and valine dipeptides with backbone torsion angles from the helical and strand regions of the Ramachandran plot. In a subset of cases these energies differ significantly from those calculated with standard molecular mechanics potentials or those derived from PDB statistics. We find that in these cases the energies from the QM methods result in more accurate placement of amino acid side chains in structure prediction tests.
The new federalism and the management of ocean resources

This paper explores the concept of federalism; that is, the division of powers between the federal government and the states, and how such a division relates to the equitable and efficient management of our increasingly important ocean and coastal resources.
Dating late Quaternary planktonic foraminifer Neogloboquadrina pachyderma from the Arctic Ocean using amino acid racemization

The long-term rate of racemization for amino acids preserved in planktonic foraminifera was determined by using independently dated sediment cores from the Arctic Ocean. The racemization rates for aspartic acid (Asp) and glutamic acid (Glu) in the common taxon, Neogloboquadrina pachyderma, were calibrated for the last 150 ka using 14C ages and the emerging Quaternary chronostratigraphy of Arctic Ocean sediments. An analysis of errors indicates realistic age uncertainties of about ±12% for Asp and ±17% for Glu. Fifty individual tests are sufficient to analyze multiple subsamples, identify outliers, and derive robust sample mean values. The new age equation can be applied to verify and refine age models for sediment cores elsewhere in the Arctic Ocean, a critical region for understanding the dynamics of global climate change.
Rehospitalization rates for patients with COPD who require supplemental oxygen therapy following a hospitalization for an exacerbation

Objective: To compare the hospital readmission rates for patients with COPD who require supplemental oxygen therapy following an exacerbation who are entered into a home-care based, respiratory therapist centered transition of care program. Method: Patients with a diagnosis of a COPD exacerbation who required supplemental oxygen therapy on hospital discharge were entered into a post hospitalization transition of care program {Discharge, Assessment and Summary @ Home (D.A.S.H., Klingensmith HealthCare, Ford City, PA)]. The program consists of face to face visits by a respiratory therapist with the patient on days 2, 7, and 30 following hospital discharge. Education, behavior modification, skills training, oxygen titration during performance of activities of daily living, clinical assessment, and adherence data collection are components of the program. The 30 day readmission rates following discharge for all patients entered into the program over a twenty four month period (March 2010 through February 2012) were evaluated. Results: 385 consecutive patients with COPD (mean age 71 + 12 years) from 23 different hospitals were enrolled into the program. 123 (31%) patients refused additional follow up after the first home visit. The 30 day readmission rate for those patients who chose to continue the program (209) was 2.8%. Conclusions: The use of a multiple visit respiratory therapist based patient centered management program resulted in a significant decrease in the 30 day readmission rates for those patients who elected to continue with the DASH management program.
Space-time coding techniques for MIMO block fading channels with co-channel interference

In this paper, we consider the design of space-time codes for multi-input multi-output systems operated in the presence of co-channel interference (CCI). In particular, we consider two different scenarios. In the first, the channel state information (CSI) is assumed to be known only at the receiver. Based on the pairwise probability of error analysis, we develop a new design criterion that determines the code robustness to co-channel interference (CCI diversity gain). We further develop an algebraic framework for constructing space-time codes that jointly optimize the fading and CCI diversity gains. The proposed framework is general for arbitrary numbers of transmit antennas and quadrature amplitude modulation (QAM) constellations. In the second scenario, we investigate adaptive space-time techniques that exploit partial CSI at the transmitter. Our proposed design combines appropriate transmit antenna selection with adaptive rate and power allocation to combat both multi-path fading and CCI.
Extraction and search of chemical formulae in text documents on the web

Often scientists seek to search for articles on the Web related to a particular chemical. When a scientist searches for a chemical formula using a search engine today, she gets articles where the exact keyword string expressing the chemical formula is found. Searching for the exact occurrence of keywords during searching results in two problems for this domain: a) if the author searches for CH4 and the article has H4C, the article is not returned, and b) ambiguous searches like "He" return all documents where Helium is mentioned as well as documents where the pronoun "he" occurs. To remedy these deficiencies, we propose a chemical formula search engine. To build a chemical formula search engine, we must solve the following problems: 1) extract chemical formulae from text documents, 2) index chemical formulae, and 3) designranking functions for the chemical formulae. Furthermore, query models are introduced for formula search, and for each a scoring scheme based on features of partial formulae is proposed tomeasure the relevance of chemical formulae and queries. We evaluate algorithms for identifying chemical formulae in documents using classification methods based on Support Vector Machines(SVM), and a probabilistic model based on conditional random fields (CRF). Different methods for SVM and CRF to tune the trade-off between recall and precision forim balanced data are proposed to improve the overall performance. A feature selection method based on frequency and discrimination isused to remove uninformative and redundant features. Experiments show that our approaches to chemical formula extraction work well, especially after trade-off tuning. The results also demonstrate that feature selection can reduce the index size without changing ranked query results much.
Leading malignant cells initiate collective epithelial cell invasion in a three-dimensional heterotypic tumor spheroid model

Solid tumors consist of genetically and phenotypically diverse subpopulations of cancer cells with unique capacities for growth, differentiation, and invasion. While the molecular and microenvironmental bases for heterogeneity are increasingly appreciated, the outcomes of such intratumor heterogeneity, particularly in the context of tumor invasion and metastasis, remain poorly understood. To study heterotypic cell-cell interactions and elucidate the biological consequences of intratumor heterogeneity, we developed a tissue-engineered multicellular spheroid (MCS) co-culture model that recapitulates the cellular diversity and fully three-dimensional cell-cell and cell-matrix interactions that characterize human carcinomas. We found that "invasion-competent" malignant cells induced the collective invasion of otherwise "invasion-incompetent" epithelial cells, and that these two cell types consistently exhibited distinct leader and follower roles during invasion. Analysis of extracellular matrix (ECM) microarchitecture revealed that malignant cell invasion was accompanied by extensive ECM remodeling including matrix alignment and proteolytic track-making. Inhibition of cell contractility- and proteolysis-mediated matrix reorganization prevented leader-follower behavior and malignant cell-induced epithelial cell invasion. These results indicate that heterogeneous subpopulations within a tumor may possess specialized roles during tumor progression and suggest that complex interactions among the various subpopulations of cancer cells within a tumor may regulate critical aspects of tumor biology and affect clinical outcome.
The Area of the Stimulus Eliciting Response as a Factor in Mirror Image Reversal

When a goldfish is trained monocularly to make an avoidance response to one of a pair of left-right mirror images, testing via the untrained eye shows a reversal of training. For example, after training to avoid ┤ but not ├, testing the opposite eye shows an avoidance of ├ , but not ┤, (Ingle, 1967). This phenomenon, interocular/interhemispheric reversal of mirror images, does not occur when up-down mirror images are used or when the stimuli subtend less than 10° of visual angle, (Campbell, 1971).
A New Operational Transformation Framework for Real-Time Group Editors

Group editors allow a group of distributed human users to edit a shared multimedia document at the same time over a computer network. Consistency control in this environment must not only guarantee convergence of replicated data, but also attempt to preserve intentions of operations. Operational transformation (OT) is a well-established method for optimistic consistency control in this context and has drawn continuing research attention since 1989. However, counterexamples to previous works have often been identified despite the significant progress made on this topic over the past 15 years. This paper analyzes the root of correctness problems in OT and establishes a novel operational transformation framework for developing OT algorithms and proving their correctness
Molecular phylogenetics and evolution of host plant use in the Neotropical rolled leaf ‘hispine’ beetle genus Cephaloleia (Chevrolat) (Chrysomelidae: Cassidinae)

Abstract Here, we report the results of a species level phylogenetic study of Cephaloleia beetles designed to clarify relationships and patterns of host plant taxon and tissue use among species. Our study is based on up to 2088 bp of mtDNA sequence data. Maximum parsimony, maximum likelihood, and Bayesian methods of phylogenetic inference consistently recover a monophyletic Cephaloleia outside of a basal clade of primarily palm feeding species (the ‘Arecaceae-feeding clade’), and C. irregularis. In all three analyses, the ‘Arecaceae-feeding clade’ includes Cephaloleia spp. with unusual morphological features, and a few species currently placed in other cassidine genera and tribes. All three analyses also recover a clade that includes all Zingiberales feeding Cephaloleia and most Cephaloleia species (the ‘Zingiberales-feeding clade’). Two notable clades are found within the ‘Zingiberales-feeding clade.’ One is comprised of beetles that normally feed only on the young rolled leaves of plants in the families Heliconiaceae and Marantaceae (the ‘Heliconiaceae & Marantaceae-feeding clade’). The other is comprised of relative host tissue generalist, primarily Zingiberales feeding species (the ‘generalist-feeding clade’). A few species in the ‘generalist-feeding clade’ utilize Cyperaceae or Poaceae as hosts. Overall, relatively basal Cephaloleia (e.g., the ‘Arecaceae clade’) feed on relatively basal monocots (e.g., Cyclanthaceae and Arecaceae), and relatively derived Cephaloleia (e.g., the ‘Zingiberales-feeding clade’) feed on relatively derived monocots (mostly in the order Zingiberales). Zingiberales feeding and specialization on young rolled Zingiberales leaves have each apparently evolved just once in Cephaloleia.
Association of Fecal Indicator Bacteria with Human Viruses and Microbial Source Tracking Markers at Coastal Beaches Impacted by Nonpoint Source Pollution

Water quality was assessed at two marine beaches in California by measuring the concentrations of culturable fecal indicator bacteria (FIB) and by library-independent microbial source tracking (MST) methods targeting markers of human-associated microbes (human polyomavirus [HPyV] PCR and quantitative PCR, Methanobrevibacter smithii PCR, and Bacteroides sp. strain HF183 PCR) and a human pathogen (adenovirus by nested PCR). FIB levels periodically exceeded regulatory thresholds at Doheny and Avalon Beaches for enterococci (28.5% and 31.7% of samples, respectively) and fecal coliforms (20% and 5.8%, respectively). Adenoviruses were detected at four of five sites at Doheny Beach and were correlated with detection of HPyVs and human Bacteroides HF183; however, adenoviruses were not detected at Avalon Beach. The most frequently detected human source marker at both beaches was Bacteroides HF183, which was detected in 27% of samples. Correlations between FIBs and human markers were much more frequent at Doheny Beach than at Avalon Beach; e.g., adenovirus was correlated with HPyVs and HF183. Human sewage markers and adenoviruses were routinely detected in samples meeting FIB regulatory standards. The toolbox approach of FIB measurement coupled with analysis of several MST markers targeting human pathogens used here demonstrated that human sewage is at least partly responsible for the degradation of water quality, particularly at Doheny Beach, and resulted in a more definitive assessment of recreational water quality and human health risk than reliance on FIB concentrations alone could have provided.
Long‐term three‐dimensional perfusion culture of human adult bone marrow mononuclear cells in bioreactors

The construction and long-term maintenance of three-dimensional in vitro bone marrow models is of great interest but still quite challenging. Here we describe the use of a multi-compartment hollow-fiber membrane based three-dimensional perfusion bioreactor for long-term culture of whole human bone marrow mononuclear cells. We also investigated bioreactors with incorporated open-porous foamed hydroxyapatite scaffolds, mimicking the in vivo bone matrix. Cells in bioreactors with and without scaffolds were cultured to 6 weeks and compared to Petri dish controls. Cells were analyzed for gene expression, surface markers by flow cytometry, metabolic activity, hematopoietic potential, viability, and attachment by immunocytochemistry. Cells in bioreactors were metabolic active during long-term culture. The percentages of hematopoietic stem cell and mature endothelial cell fractions were maintained in bioreactors. The expression of most of the analyzed genes stabilized and increased after long-term culture of 6 weeks. Compared to Petri dish culture controls, bioreactor perfusion culture improved in both the short and long-term, the colony formation unit capacity of hematopoietic progenitors. Cells attached to the ample surface area provided by hydroxyapatite scaffolds. The implementation of a hydroxyapatite scaffold did not influence colony formation capacity, percentages of cell type specific fractions, gene expression, cell viability or metabolic turnover when compared to control cells cultured in bioreactors without scaffolds. In conclusion, three-dimensional perfusion bioreactor culture enables long-term maintenance of primary human bone marrow cells, with hydroxyapatite scaffolds providing an in vivo-like scaffold for three-dimensional culture.
Machine learning for information architecture in a large governmental Web site

This paper describes ongoing research into the application of machine learning techniques for improving access to governmental information in complex digital libraries. Under the auspices of the GovStat Project, our goal is to identify a small number of semantically valid concepts that adequately spans the intellectual domain of a collection. The goal of this discovery is twofold. First we desire a practical aid for information architects. Second, automatically derived document-concept relationships are a necessary precondition for real-world deployment of many dynamic interfaces. The current study compares concept learning strategies based on three document representations: keywords, titles, and full-text. In statistical and user-based studies, human-created keywords provide significant improvements in concept learning over both title-only and full-text representations.
Are History Textbooks More “Considerate” After 20 Years?

Features of eighth-grade history textbooks were examined through replication of a 20-year-old study that investigated “considerateness” of textbooks. Considerate texts provide clear, coherent information and include features that promote students’ comprehension, such as explicit use of organizational structures, a range of question types dispersed within and at the end of chapters, and highlighted new vocabulary. Conversely, inconsiderate texts can impede student learning because comprehension is influenced by coherence and clarity between and among new vocabulary, sentences, paragraphs, and passages at macro and micro levels throughout texts’ chapters. Results of this study indicate areas where today’s texts are more clear and coherent than those 20 years ago, and areas where improvements within textbooks are still needed. Implications for practice are discussed.
The evaluation and calibration of fan-beam collimators.

The aims of this study were (a) to determine the true focal length of a fan-beam collimator and (b) to calibrate image size (mm/pixel) for each collimator to permit inter-comparison of image data acquired on different gamma camera systems. A total of six fan-beam collimators on three dual-head gamma camera systems were evaluated using a set of four cobalt-57 point source markers. The markers were arranged in a line in the transverse plane with a known separation between them. Tomographic images were obtained at three radii of rotation. From reconstructed transaxial images the distance between markers was measured in pixels and used to determine pixel size in mm/pixel. The system value for the focal length of the collimator was modified by up to ±100 mm and transaxial images were again reconstructed. To standardize pixel size between systems, the apparent radius of rotation during a single-photon emission tomography (SPET) acquisition was modified by changes to the effective collimator thickness. SPET images of a 3D brain phantom were acquired on each system and reconstructed using both the original and the modified values of collimator focal length and thickness. Co-registration and subtraction of the reconstructed transaxial images was used to evaluate the effects of changes in collimator parameters. Pixel size in the reconstructed image was found to be a function of both the radius of rotation and the focal length. At the correct focal length, pixel size was essentially independent of the radius of rotation. For all six collimators, true focal length differed from the original focal length by up to 26 mm. These differences in focal length resulted in up to 6% variation in pixel size between systems. Pixel size between the three systems was standardized by altering the value for collimator thickness. Subtraction of the co-registered SPET images of the 3D brain phantom was significantly improved after optimization of collimator parameters, with a 35%–50% reduction in the standard deviation of residual counts in the subtraction images. In conclusion, we have described a simple method for measurement of the focal length of a fan-beam collimator. This is an important parameter on multidetector systems for optimum image quality and where accurate co-registration of SPET to SPET and SPET to MRI studies is required.