cssi/SciSciGPT-SciSciNet huggingface dataset:
Why Clusters and Other Patterns Can Seem to be Found in Analyses of High-Dimensional Data

Recent papers by Cardini et al. (Evolutionary Biology 46:307–316, 2019) and Bookstein (Evolutionary Biology 46:271–302, 2019) show that, when there are many variables and when sample sizes are small, scatterplots made using the between-groups principal components analysis method can appear to indicate clear group differences with little or no overlap between samples even though the samples are all drawn from a single multivariate normally distributed population. The corresponding scatterplots made after a canonical variates analysis (CVA) show an even more extreme separation of groups even though the usual test statistics yield the correct uniform distribution of probabilities. Users of CVA are usually concerned about the problems of small sample sizes and correlated variables but the problems discussed here are present even for large samples and uncorrelated variables. Some less-appreciated properties of sampling from high-dimensional spaces and the “curse of dimensionality” are reviewed to find a simple explanation for these problems. The ratio of variables to sample size is a useful index to predict when false clusters and these other problems may arise. While dependent upon the same variables, this index is not based on Marchenko and Pastur (Mathematics of the USSR–Sbornik 1:457–483, 1967) as discussed by Bookstein (Evolutionary Biology 44:522–541, 2017). It is also shown that multiple regression analysis can have related problems when there are large numbers of independent variables. The explanation for these problems is an incompatibility of showing both points separated by their full p-dimensional distances and low-dimensional projections of points in the same plot. Some implications for geometric morphometric and other multivariate analyses in biology are also discussed.
Scanning Probe Microscopy

Several techniques have been developed over the past decade using near-field effects to obtain high-resolution microscopic images and surface microanalysis. These techniques are referred to as scanning probe microscopies (SPM). In each of these microscopies, a sharpened probe is used to measure a specific interaction between the probe and the surface of interest. The instrument which began this new and expanding field of microscopy is the scanning tunneling microscope (STM) invented in 1981 by Binnig, Rohrer, and coworkers (1982a–c). The STM measures the electronic interaction between a conductive or semiconductive probe and sample which allows the direct imaging of geometric and electronic surface structure with atomic resolution. Several reviews of the STM literature have been published (Golovchenko, 1986; Hansma and Tersoff, 1987; Binnig and Rohrer, 1987; Kuk and Silverman, 1989; Demuth et al., 1988; Griffith and Kochanski, 1990).
DataRover: An Automated System for Extracting Product Information From Online Catalogs

The increasing number of e-commerce Web sites on the Web introduces numerous challenges in organizing and searching the product information across multiple Web sites. This problem is further exacerbated by various presentation templates that different Web sites use in presenting their product information, and different ways of product information they store in their catalogs. This paper describes the DataRover system, which can automatically crawl and extract all products from online catalogs. DataRover is based on pattern mining algorithms and domain specific heuristics which utilize the navigational and presentation regularities to identify taxonomy, list-of-product and single-product segments within an online catalog. Next, it uses the inferred patterns to extract data from all such data segments and to automatically transform an online catalog into a database of categorized products. We also provide experimental results to demonstrate the efficacy of the DataRover.
Evidence of a pronounced preference for therapy guided by common factors.

Objective Recent evidence presented in this journal (Swift & Callahan, 2010) suggests that psychotherapy clients may place more value on nonspecific common factors—such as a warm and relatable therapist—than on the level of empirical support for a particular intervention. The present study investigated the possibility that this trend would also extend to those who have never received professional psychological help. Method Three hundred and twenty-nine adults from across the United States (60.2% female, mean age = 35.92) each rated their attitudes toward seeking two varieties of psychotherapy: one emphasizing nonspecific common factors, and one emphasizing specific evidence-based therapy ingredients. Results Analyses revealed a pronounced preference for therapy guided by common factors among clients and nonclients alike, even when controlling for a host of individual difference variables. Conclusions These data conceptually replicate Swift and Callahan's findings and indicate that potential clients may seek help more readily from providers who accentuate the nonspecific aspects of therapy.
Protein synthesis in virus-infected plants. II. The synthesis and accumulation of TMV and TMV coat protein in subcellular fractions of TMV-infected tobacco.

Abstract Subcellular fractions of TMV-infected leaves, obtained after 2 hr of 3 H-leucine incorporation after various times of infection or continuous 3 H-leucine labeling for long periods after infection, were assayed for infectivity and, after denaturation with SDS, analyzed for total TMV coat protein by acrylamide gel electrophoresis. The nuclear and mitochondrial fractions contained little or no detectable infectivity and coat protein. The cytoplasmic fraction did not contain any viral infectivity, but with short labeling it contained a high proportion of the total labeled coat protein. After long, continuous labeling, the proportion of total labeled coat protein in the cytoplasm was low, indicating that most of the newly synthesized protein was used to coat viral RNA. Although the ribosomal fraction sedimenting at 105,000 g contained the majority of the infective virus, the chloroplast fraction appeared to be a site of virus storage since virus, increasing with time of infection, was associated with it. At early stages of infection, up to half of the total short labeled coat protein was present in the chloroplast fraction. This high proportion of protein decreased with time of infection, and with long labeling became low. Since the rapidly labeled protein was not found free, and was greatly in excess of the virus concentration, when compared to the ratio of labeled protein to virus in the mitochondrial or ribosomal fractions, it is postulated that the chloroplasts are a site of virus assembly.
Electron–positron jets associated with the quasar 3C279

A long-standing question in extragalactic astrophysics is the composition of the relativistic jets of plasma that stream from the nuclei of quasars and active galaxies—do they consist of a ‘normal’ (electron–proton) plasma, or a ‘pair’ (electron–positron) plasma? Distinguishing between these possibilities is crucial for understanding the physical processes occurring close to the putative supermassive black holes that are believed responsible for the jets. Here we report the detection of circularly polarized radio emission from the jets of the archtypal quasar 3C279. The circular polarization is produced by Faraday conversion, which requires the energy distribution of the radiating particles to extend to very low energies, indicating that electron–positron pairs are an important component of the jet plasma. Similar detections in three other radio sources suggest that, in general, extragalactic radio jets are composed mainly of an electron–positron plasma.
Relationships among some relatively deep-bodied percoid fish groups.

Etude portant sur 11 familles: Kyphosidae, Scorpididae, Girellidae, Labracoglossidae, Oplegnathidae, Pomacanthidae, Chaetodontidae, Monodactylidae, Ephippidae, Drepanidae et Scatophagidae
A Method to Evaluate Fetal Erythropoiesis from Postnatal Survival of Fetal RBCs.

Fetal RBCs are produced during a period of very rapid growth and stimulated erythropoiesis under hypoxic intrauterine conditions. Fetal RBC life span varies with gestational age (GA) and is shorter than that in healthy adults. Due to the special kinetic properties of life span-based survival of human RBCs, a mathematical model-based kinetic analysis of the survival of fetal RBCs shortly after birth provides a unique opportunity to “look backward in time” to evaluate fetal erythropoiesis. This work introduces a novel method that utilizes postnatal in vivo RBC survival data collected within 2 days after birth to study both nonsteady-state (non-SS) in utero RBC production and changing fetal RBC life span over time. The effect of changes in erythropoiesis rate and RBC life span and the effect of multiple postnatal phlebotomies on the RBC survival curves were investigated using model-based simulations. This mathematical model, which considers both changes in the rate of erythropoiesis and RBC life span and which accurately accounts for the confounding effect of multiple phlebotomies, was applied to survival curves for biotin-labeled RBCs from ten anemic very low birth weight preterm infants. The estimated mean fetal RBC production rate scaled by body weight was 1.07 × 107 RBCs/day g, and the mean RBC life span at birth was 52.1 days; these values are consistent with reported values. The in utero RBC life span increased at a rate of 0.51 days per day of gestation. We conclude that the proposed mathematical model and its implementation provide a flexible framework to study in utero non-SS fetal erythropoiesis in newborn infants.
A Review of the LARIAT Suture Delivery Device for Left Atrial Appendage Closure

The prevalence of atrial fibrillation (AF) is 1-2 % in the general population, and the risk of embolic stroke in AF patients is 4-5 times higher than that in the general population. AF-related strokes are often severe, and the rate of permanent disability is much higher among individuals who have AF-related strokes than in those who have strokes unrelated to AF. In patients with AF, more than 90 % of thrombi originate from the left atrial appendage (LAA). The purpose of this paper is to review the efficacy and safety of performing the LAA closure with the LARIAT Suture Delivery Device to prevent AF-related stroke in patients with contraindications to oral anticoagulant therapy.
Adsorption and attenuation behavior of 3-nitro-1,2,4-triazol-5-one (NTO) in eleven soils

NTO (3-nitro-1,2,4-triazol-5-one) is one of the new explosive compounds used in insensitive munitions (IM) developed to replace traditional explosives, TNT and RDX. Data on NTO fate and transport is needed to determine its environmental behavior and potential for groundwater contamination. We conducted a series of kinetic and equilibrium batch experiments to characterize the fate of NTO in soils and the effect of soil geochemical properties on NTO-soil interactions. A set of experiments was also conducted using sterilized soils to evaluate the contribution of biodegradation to NTO attenuation. Measured pH values for NTO solutions decreased from 5.98 ± 0.13 to 3.50 ± 0.06 with increase in NTO concentration from 0.78 to 100 mg L(-1). Conversely, the pH of soil suspensions was not significantly affected by NTO in this concentration range. NTO experienced minimal adsorption, with measured adsorption coefficients being less than 1 cm(3) g(-1) for all studied soils. There was a highly significant inverse relationship between the measured NTO adsorption coefficients and soil pH (P = 0.00011), indicating the role of NTO and soil charge in adsorption processes. In kinetic experiments, 1st order transformation rate constant estimates ranged between 0.0004 h(-1) and 0.0142 h(-1) (equivalent to half-lives of 72 and 2 d, respectively), and correlated positively with organic carbon in the soil. Total attenuation of NTO was higher in untreated versus sterilized samples, suggesting that NTO was being biodegraded. The information presented herein can be used to help evaluate NTO potential for natural attenuation in soils.
Four Constructions of Highly Symmetric Tetravalent Graphs

Given a connected, dart-transitive, cubic graph, constructions of its Hexagonal Capping and its Dart Graph are considered. In each case, the result is a tetravalent graph which inherits symmetry from the original graph and is a covering of the line graph.Similar constructions are then applied to a map (a cellular embedding of a graph in a surface) giving tetravalent coverings of the medial graph. For each construction, conditions on the graph or the map to make the constructed graph dart-transitive, semisymmetric or -transitive are considered. © 2012 Wiley Periodicals, Inc. (Contract grant sponsor: National Science Foundation; Contract grant number: DMS-0139523 (to A. H.).)
1,2,4-Thiadiazole†

[288-92-6] C2H2N2S (MW 86.11) InChI = 1S/C2H2N2S/c1-3-2-5-4-1/h1-2H InChIKey = YGTAZGSLCXNBQL-UHFFFAOYSA-N (prepared from 5-bromo-1,2,4-thiadiazole) Alternate Name(s): 1-thia-2,4-diazacyclopentadiene; 2,4-diazathiophene. Physical Data: mp −33 to −35 °C, bp753 120.7–121.2 °C, d 1.3298 g mL−1 at 20 °C, 1.5316; λmax 229 nm (log ϵ = 3.73).2 Solubility: soluble in water, diethyl ether, ethanol, acetone, and glacial acetic acid; slightly soluble in benzene, petroleum ether, carbon tetrachloride, and ethyl acetate.2 Form Supplied in: colorless liquid; not commercially available.
Synthesis of developmentally regulated proteins in Dictyostelium discoideum which are dependent on continued cell-cell interaction.

Abstract In the previous paper we showed that the major changes in the pattern of protein synthesis during differentiation of Dictyostelium discoideum occur during the 4-hr period when the cells are forming tight, visible aggregates. During this time, synthesis of 10 discrete polypeptides made by preaggregation cells ceases or is reduced considerably, and synthesis of 40 new proteins is induced. Induction or cessation of synthesis of these proteins was parallelled by the appearance or disappearance of the corresponding messenger RNAs. In this paper we show that many of these changes are induced by continued cell-cell contact. None of these occurs in aggregation-competent cells kept in suspension culture, but changes do take place when such cells are allowed to form tight aggregates. Disaggregation of cells causes cessation of synthesis of “aggregation-stage” proteins and reinduction of synthesis of polypeptides characteristic of preaggregation cells.
Sensitivity of the comprehensive trail making test to traumatic brain injury in adolescents

The current study examined the sensitivity of the Comprehensive Trail Making Test (CTMT Reynolds) to neurocognitive deficits in adolescents with traumatic brain injury (TBI). Participants included 60 adolescents, 30 who had sustained TBI and 30 healthy controls (HC) that were individually matched to the TBI sample on age, gender, ethnicity, and geographical region. For both the TBI and HC groups the mean age was 15.0 years (S.D.=2.3 years, range=11-19). The TBI group had a mean IQ of 81.7 (S.D.=14.9), had sustained moderate to severe brain injury, and was assessed an average of 21.1 months (S.D.=20.7) following injury. The TBI group performed approximately 2 standard deviations below the control sample mean on each of the five CTMT trails as well as on the composite index and these differences were significant (p<.001). Significant correlations were present between the CTMT trails and clinical variables associated with brain injury severity. Finally, receiver operating characteristic analyses indicated good classification of the TBI and control cases for the CTMT, although some variability in classification accuracy was present among the various trails. Results suggest that the CTMT is sensitive to TBI in adolescents but continued research is needed with larger samples of individuals with TBI and other types of neurological disorders to further establish the present findings.
Economic Development: Is This a Solution for Rural Poverty: Discussion

T HE DESIGN of economic development programs as prescriptions for rural poverty necessitates an understanding of the unique properties of rural poverty. I consider the central feature or root cause of rural poverty to be involuntary underemployment. Underemployment results from employment of labor resources on an irregular basis or in jobs of low productivity, with annual wages below those of comparably endowed workers in other employments. It is the result of people earning less than their potential, or their use of inefficient methods of production from which they receive little income.
Long‐term variation in the thermosphere: TIMED/GUVI observations

[1] Long-term changes in the thermospheric composition (O/N2 column density ratio) and exospheric temperature (Texo) have been examined. The data are obtained from TIMED/GUVI disk and limb measurements over half of a solar cycle from 2002 to 2007. The data indicate a positive correlation between O/N2 and solar EUV flux (Qeuv), despite large variability in O/N2 due to geomagnetic activity and season and local time effects. A function fitting provides quantitative specification of the O/N2 dependence on Qeuv. The magnitude of changes in O/N2 due to solar EUV variation between 2002 and 2007 is 40% of the mean (0.5) O/N2 over the same period and is of the same order to the changes in O/N2 due to nonsolar EUV effects (geomagnetic activity, season, and local time). Similar results are also obtained for the Texo dependence on Qeuv. The O/N2 dependence on Qeuv is due to thermal expansion or contraction that alters the reference height of the fixed N2 column density (1017 cm−2). This differs from the O/N2 depletion associated with high Texo during storm time where upward wind plays an important role.
Nicotine delays arousal during hypoxemia in lambs.

A decreased ability to arouse from sleep in response to arterial hypoxemia may lead to severe asphyxia and has been proposed as a mechanism of sudden infant death syndrome. Based on previous observations that nicotine exposure, a major environmental risk factor for sudden infant death syndrome, may impair hypoxic defense in neonates, we hypothesized that a short-term infusion of nicotine could impair hypoxic arousal through interference with oxygen-sensing mechanisms. Seven chronically instrumented unanesthetized lambs were studied at the age of 4.6 ± 1.3 d during normoxia and acute hypoxia (0.1 fraction of inspired oxygen) for 5 min. Ventilation, transcutaneous Hb oxygen saturation, blood pressure, heart rate, and time to arousal were compared during a control saline infusion and during a 0.5 μg·kg−1·min−1 nicotine infusion. Activity states, i.e. wakefulness and quiet sleep as well as arousal, were defined by EEG, nuchal electromyogram, and electrooculogram. Each lamb acted as its own control. Arousal from quiet sleep occurred significantly later during nicotine infusion compared with control (177 ± 93 versus 57 ± 41 s, p < 0.01) and at a lower transcutaneous Hb oxygen saturation (60 ± 12 versus 79 ± 12%, p < 0.01) (paired t test). The ventilatory response to hypoxia in wakefulness was similar during both conditions but was significantly attenuated in quiet sleep during nicotine infusion (p < 0.001, 2-way ANOVA repeated-measures design). Blood pressure and heart rate responses were similar during both conditions. These results suggest that a brief nicotine exposure blunts oxygen sensitivity in young lambs, a finding of potential relevance for sudden infant death syndrome.
Leading the Way for Financial Literacy Education: A Case Study on Collaboration

Academic libraries have been involved in financial literacy education, and this will likely increase in the future. This article demonstrates how the author, a business and economics librarian, led the way at her institution to bring financial literacy to the campus by participating in the national Money Smart Week (MSW) program sponsored by the Federal Reserve Bank of Chicago. She formed a planning committee that included individuals from several campus units. This team organized, planned, and delivered 11 events during MSW. The author also discusses survey results and the instrument that was used to gather data from MSW attendees.
Genomic and Population-Level Effects of Gene Conversion in Caenorhabditis Paralogs

Interlocus gene conversion, the nonreciprocal exchange of genetic material between genes, is facilitated by high levels of sequence identity between DNA sequences and has the dual effect of homogenizing intergenic sequences while increasing intragenic variation. Gene conversion can have important consequences for the evolution of paralogs subsequent to gene duplication, as well as result in misinterpretations regarding their evolution. We review the current state of research on gene conversion in paralogs within Caenorhabditis elegans and its congeneric species, including the relative rates of gene conversion, the range of observable conversion tracts, the genomic variables that strongly influence the frequency of gene conversion and its contribution to concerted evolution of multigene families. Additionally, we discuss recent studies that examine the phenotypic and population-genetic effects of interlocus gene conversion between the sex-determination locus fog-2 and its paralog ftr-1 in natural and experimental populations of C. elegans. In light of the limitations of gene conversion detection methods that rely solely on the statistical distribution of identical nucleotides between paralogs, we suggest that analyses of gene conversion in C. elegans take advantage of mutation accumulation experiments and sequencing projects of related Caenorhabditis species.
Myeloid and lymphoid neoplasm with abnormalities of FGFR1 presenting with trilineage blasts and RUNX1 rearrangement: a case report and review of literature.

Objectives: Myeloid and lymphoid neoplasms with abnormalities of fibroblast growth factor receptor 1 gene (FGFR1) are a rare and aggressive disease group that harbors translocations of FGFR1 with at least 14 recognized partner genes. We report a case of a patient with a novel t(17;21)(p13;q22) with RUNX1 rearrangement and trilineage blasts. Methods: A 29-year-old man with relapsed T-lymphoblastic lymphoma in the cervical nodes showed a myeloproliferative neoplasm in his bone marrow with three separate populations of immunophenotypically aberrant myeloid, T-lymphoid, and B-lymphoid blasts by flow cytometry. Cytogenetic and fluorescent in situ hybridization studies showed unique dual translocations of t(8;13)(p11.2;q12) and t(17;21)(p13;q22) with RUNX1 rearrangement. Results: The patient was initiated on a mitoxantrone, etoposide, and cytarabine chemotherapy regimen and died of complications of disease 1 month later. Conclusions: To our knowledge, this is the first reported case of a myeloid and lymphoid neoplasm with abnormalities of FGFR1 with t(17;21)(p13;q22) and trilineage blasts.
Electron-transfer and acid-base properties of a two-electron oxidized form of quaterpyrrole that acts as both an electron donor and an acceptor.

Electron-transfer interconversion between the four-electron oxidized form of a quaterpyrrole (abbreviated as P4 for four pyrroles) and the two-electron oxidized form (P4H2) as well as between P4H2 ...
Recent Historiography and the History of Religions: an Appreciative Response To Arthur McCalla

One of the several ironies that characterizes the modern study known as the "history of religions" is that this approach has come to designate for many an essentially ahistorical method.1 For those of us who maintain that the study of religion should include the history of religions, Arthur McCalla's recent article on "The Importance of Recent Historiography for the Study of Religious Thought" (MTSR 2/2 [1990], 167-179) is a welcome contribution to the theoretical literature of the field. McCalla's article is born from his concern with religious thought and its fate following the attacks, in the 1930s, on the history of ideas generally by Lucien Febvre and Marc Bloch. These historians, in the summary of McCalla, denounced the practice of intellectual history for its isolation of "ideas from the societies in which they were produced and operated" (168). Their alternative historiography, associated with the French Annales school, emphasized the collective conditioning of inte llectual and cultural artifacts, a historical practice that became known by the 1960s, as "the history of mentalites" (168-9).2 This concern with collectives rather than with individuals, or with their thought, directed this
A Marshall-Olkin Power Log-normal Distribution and Its Applications to Survival Data

In this paper, using Marshall-Olkin transformation, a new class of Extended Power Log-normal distribution which includes the Power Log-normal and Log-normal distributions as special cases is introduced. Its characterization and statistical properties are studied. A real survival dataset is analyzed and the results show that the proposed model is flexible and appropriate.
Characterization of plasmids from Haemophilus parainfluenzae and Haemophilus haemolyticus.

Abstract The laboratory strains of Haemophilus parainfluenzae and Haemophilus haemolyticus that are commonly used as restriction enzyme sources carry several small multicopy plasmids. H. parainfluenzae carries plasmids pKC1, pKC2, and pKC3 of sizes 1.50, 2.86, and 3.84 kb, respectively, as determined by gel electrophoresis and electron microscopy. H. haemolyticus carries plasmids pKC4 and pKC5 of sizes 1.3 and 1.7 kb as determined by gel electrophoresis. At least two of the plasmids pKC1 and pKC4 were successfully transferred into E. coli by cotransfection with plasmid pBR322. They are compatible with pBR322 and have a comparable copy number.
Probing Predispositions: The Pragmatism of a Process Perspective

— As J. P. Spencer et al. (2009) argue, the theories of some developmental psychologists continue to be nativistic, even though nativism is an inherently nondevelopmental school of thought. Psychologists interested in development study the emergence of human characteristics—including predispositions—and are not content to simply catalogue competences that characterize human newborns; instead, they recognize that all human characteristics, including those present at birth, reflect the circumstances of development. A truly developmental science of behavior requires rejecting the nativism–empiricism debate outright, abandoning ideas such as “core knowledge” and psychological “endowments,” and adopting a process perspective that focuses on how traits emerge from the co-actions of biological and experiential factors. Unlike nativism, the process perspective advocated by J. P. Spencer et al. encourages research that can reveal the developmental origins of psychological characteristics of interest.
Myocardial injury in meningococcus-induced purpura fulminans in children

Objectives: To assess the incidence of myocardial ischemia in meningococcus-induced purpura fulminans in pediatric patients, to compare troponin I (cTnI) levels with changes in electrocardiogram (ECG) and to evaluate whether cTnI is related to myocardial function and contractility, to severe acquired anticoagulant deficiency and to the severity of disease. Methods: Twenty-two patients with acute meningococcemia, supported with inotropes or vasoactive agents, were studied. Blood samples for the determination of serum cTnI and conventional myocardial ischemia and coagulopathy markers were drawn daily. Measurements of cardiac index (CI), ejection (EF) and shortening fractions (SF) and ECGs were performed daily. Results: The Leclerc score, the Neisseria sepsis index (NESI) and the pediatric risk of mortality (PRISM) score predicted a mean mortality rate of 34%, 27% and 23%, respectively. Four patients died (18%). Five patients (23%) presented with myocardial ischemia. Their ECG ischemic changes were associated with pathologically high cTnI levels (1.93±0.13 vs 0.18±0.08 ng/ml, p<0.001 for patients with or without ischemic changes) and depressed myocardial contractility (mean difference ± SE –14±5%, p=0.01, for the EF and –7.4±3, p<0.02, for the SF). High cTnI values were significantly correlated to low protein C (PC) (p<0.0001), factor VIII (p<0.04) and antithrombin III (AIII, p=0.01) levels, but not to the PRISM, Leclerc or the NESI scores. Means of AIII, VII, and especially of VIII, and PC, were significantly lower in ischemic than in non-ischemic patients, although severity scoring systems and inotropic support did not differ between the two groups. Survivors tended to significantly higher PC (p<0.01) and factor VIII levels (p=0.001) than non-survivors and, also, to lower levels of cTnI (p=0.05) and CPK-MB (p<0.05), while in meningococcal shock. Conclusions: The incidence of myocardial ischemia is increased in acute meningococcemia in pediatric patients and correlates with myocardial dysfunction. High cTnI is associated with severe coagulopathy, but not with clinical prognostic scores or inotropic support. Early recognition of myocardial injury, myocardial support and early replacement therapy with PC, AIII, factor VIII or fibrinogen might improve outcome in acute meningococcemia in children.
Pectin aggregation number by light scattering and reducing end-group analysis

Abstract Pectin determination by the copper-arsenomolybdate method is effectively a count of the total number of polymer molecules in a molar mass, ultimately yielding a number average molecular weight ( M n ). Light-scattering measurements yield a weight average ( M w ) of the number of light-scattering species that may be polymer molecules or aggregates of molecules, depending on solution (dispersion) conditions. Hence, the ratio M w / M n , may be interpreted as an aggregation number directly quantifying the molecules of pectin in the weight-average molar mass, under normal conditions of use of this polymer.
Gemini Surfactants at Solid−Liquid Interfaces: Control of Interfacial Aggregate Geometry

Recent work has shown that conventional surfactants form ordered aggregates of well-defined shape and size at solid−liquid interfaces.1,2 Here we report interfacial aggregate structures as a function of surfactant geometry by using gemini surfactants with varying tail and spacer lengths. On the anionic cleavage plane of mica, aggregates tend to favor a lower curvature than in solution but follow the same general variation with surfactant geometry (i.e., with larger headgroup areas resulting in greater curvature). These morphologies on mica correlate well with those observed in surfactant−silicate mesophases, where electrostatic binding of headgroups also plays a dominant role. In addition, interfacial sphere-to-rod transitions are induced on mica (as in free solution) by binding with a headgroup-specific counterion. In contrast to mica, the hydrophobic cleavage plane of graphite interacts with surfactant tailgroups, giving rise to interfacial aggregates that are surface-controlled and relatively independe...
An investigation on integrating XML-based security into Web services

Web services provide many benefits for developing Web applications based on SOA (Service Oriented Architecture). However, there are some open issues such as security that need to be addressed by standard bodies and technology vendors in order for Web services to become a viable solution for building global service oriented architectures. As a result, much emphasis has been placed on the development of various high-level security standards and protocols, but in many cases the simplest application level attacks have been ignored by the developers. This article covers the dependency of Web services on XML, the various forms of XML-based attacks, famous standards about XML security and finally provides recommendation and countermeasures. This publication tends to provide an understanding of the challenges in integrating information security practices into Web services design and development.
More than Teacher Directed or Child Initiated: Preschool Curriculum Type, Parent Involvement, and Children's Outcomes in the Child-Parent Centers.

This study investigated the contributions of curriculum approach and parent involvement to the short- and long-term effects of preschool participation in the Title I Chicago Child-Parent Centers. Data came from the complete cohort of 989 low-income children (93% African American) in the Chicago Longitudinal Study, who attended preschool in the 20 Child-Parent Centers in 1983-1985 and kindergarten in 1985-1986. We found that implementation of an instructional approach rated high by Head Teachers in teacher-directed and child-initiated activities was most consistently associated with children’s outcomes, including school readiness at kindergarten entry, reading achievement in third and eighth grades, and avoidance of grade retention. Parent involvement in school activities, as rated by teachers and by parents, was independently associated with child outcomes from school readiness at kindergarten entry to eighth grade reading achievement and grade retention above and beyond the influence of curriculum approach. Findings indicate that instructional approaches that blend a teacher-directed focus with child-initiated activities and parental school involvement are origins of the long-term effects of participation in the Child-Parent Centers.
Noninvasive Assessment of Left Ventricular Viability: Did We Underestimate the Potential of Stress Echocardiography

The presence of myocardial viability within a noncontracting infarct zone is an important determinant for left ventricular function recovery after interventional coronary revascularization. However, this holds true only for hibernating myocardium in which a perfusion-limiting infarct-associated coronary artery stenosis persists (in contrast to stunning with postischemic reperfusion and spontaneous recovery). Echocardiographic techniques are highly valuable in identifying hibernation, especially in conjunction with dobutamine titration. Low doses may detect the inotropic reserve by significant enhancement of segmental wall-motion abnormalities while high doses may surpass the ischemic threshold and the wall motion deteriorates (biphasic response). Dobutamine echocardiography should not be performed too early after the infarct, not only because of security reasons (arrhythmogenic potential), but also because of higher diagnostic accuracy (resolution of stunning within the first several days postmyocardial infarction thereby separating viable myocardium attributed to hibernation). According to the Task Forces on Clinical Application of Echocardiography by the American Heart Association in cooperation with the American College of Cardiology, dobutamine echocardiography is officially recommended for the purpose of clinical decision making in respect to revascularization therapies (whether during the subacute infarct period or, especially, in chronic left ventricular dysfunction due to coronary artery disease).
Impact of social support on outcome in first stroke.

The purpose of this study is to examine the impact of social support on outcome after first stroke in a prospective cohort study. Although modest evidence exists for the importance of several psychosocial factors, studies have failed to use widely recognized measures of outcome and social support, have failed to control for time since onset, and have not used longitudinal techniques.Forty-six surviving patients were followed for 6 months after stroke. Recovery was measured using repeated measures of functional status as indicated by the Barthel Index of activities of daily living. Perceived social support was measured at 1, 3, and 6 months after onset. Repeated-measures multivariate analysis of variance was used to analyze changes in functional status.Significant differences were found across levels of social support in trajectories of functional status (p = 0.002). A significant three-way interaction between stroke severity, social support, and outcome was also found (p = 0.012). Patients with more sever...
APPLICATION OF CAPILLARY ELECTROPHORESIS TO THE MEASUREMENT OF OLIGONUCLEOTIDE CONCENTRATION AND PURITY OVER A WIDE DYNAMIC RANGE

Synthetic oligonucleotides rarely contain 100% of the full-length sequence due, in part, to the failure sequences produced during synthesis. In this paper, a method is described for the determination of both the concentration and the purity of oligonucleotides, utilizing capillary electrophoresis with a deoxyribo-nucleoside triphosphate as an internal standard. This method is advantageous for several reasons: (a) the wide dynamic range allows for the analysis of samples without the need for dilutions; (b) a small sample size is used for analysis; (c) capillary electrophoresis is automatable which allows for high throughput; and (d) all of the samples are analyzed at the same run temperature which aids in reproducibility and consistency between runs performed at different times.
Randomized clinical trials in the presence of diagnostic uncertainty: Implications for measures of efficacy and sample size

Diagnostic uncertainty, particularly prior to the receipt of test results, is common in medicine. When randomized trials are being conducted to evaluate therapies in these situations, patients must be randomized in the absence of a definitive diagnosis. This article explores some of the implications of diagnostic uncertainty for the design and analysis of randomized clinical trials, using specific therapeutic examples to illustrate the important points.
Parental R-rated movie restriction and early-onset alcohol use

Objective:The aim of this study was to determine if parental restriction regarding Restricted-rated movies (R movies) predicts lower rates of early-onset alcohol use. Method:Students from 15 northern New England middle schools were surveyed in 1999, and never-drinkers were resurveyed 13–26 months later to determine alcohol use. Drinking was determined by the question, “Have you ever had beer, wine, or other drink with alcohol that your parents didn't know about?” R-movie restriction was assessed by the question, “How often do your parents allow you to watch movies that are rated R?” Results:The sample included 2,406 baseline never-drinkers who were surveyed at follow-up, of whom 14.8% had initiated alcohol use. At baseline, 20% reported never being allowed to watch R movies, and 21% reported being allowed all the time. Adolescents allowed to watch R-rated movies had higher rates of alcohol initiation (2.9% initiation among never allowed, 12.5% once in a while, 18.8% sometimes, and 24.4% all the time). Con...
Robots and rodents: children's inferences about living and nonliving kinds

This study tests the firm distinction children are said to make between living and nonliving kinds. Three, 4-, and 5-year-old children and adults reasoned about whether items that varied on 3 dimensions (alive, face, behavior) had a range of properties (biological, psychological, perceptual, artifact, novel, proper names). Findings demonstrate that by 4 years of age, children make clear distinctions between prototypical living and nonliving kinds regardless of the property under consideration. Even 3-year-olds distinguish prototypical living and nonliving kinds when asked about biological properties. When reasoning about nonbiological properties for the full range of items, however, even 5-year-olds and adults occasionally rely on facial features. Thus, the living/nonliving distinction may have more narrow consequences than previously acknowledged.
A Noninvasive Determination of Fistula Blood Flow in Dialysis Patients

Arteriovenous fistula (AVF) blood flow was evaluated in 32 dialysis patients using a pulsed Doppler velocimeter with two dominant features: a range-gated time system and a double transducer probe. With the proposed apparatus, the observation angle between the ultrasound beam and the vessel axis was known. In radial AVF, blood flow was 728 +/- 53 ml/min and was negatively correlated with the age of the AVF (r = -0.62; p less than 0.01). In brachial AVF, blood flow was 778 +/- 152 ml/min. In bovine heterograft AVF, blood flow was 1,225 +/- 125 ml/min. In the overall population, a negative relationship was observed between the diameter of the fistula and the blood flow velocity (r = -0.57; p less than 0.01). The study describes an accurate noninvasive method for the determination of fistula blood flow in dialysis patients, which may be helpful in the follow-up of the regional hemodynamics of this vascular access.
Effects of Using an Ipod App to Manage Recreation Tasks.

A withdrawal design study evaluated the effectiveness of using constant time delay to teach six adults with a developmental disability to program and use an iPod touch® as an electronic photographi...
c-Axis Electrodynamics as Evidence for the Interlayer Theory of High-Temperature Superconductivity

In the interlayer theory of high-temperature superconductivity, the interlayer pair tunneling energy (similar to the Josephson or Lawrence-Doniach energy) is the motivation for superconductivity. This connection requires two experimentally verifiable identities: the coherent normal-state conductance must be smaller than the “Josephson” coupling energy, and the Josephson coupling energy must be equal to the condensation energy of the superconductor. The first condition is well satisfied in the only case that is relevant, (La,Sr)2CuO4, but the second condition has been questioned. It is satisfied for all dopings in (La,Sr)2CuO4 and also in optimally doped Hg(Ba)2CuO5, which was measured recently, but seems to be strongly violated in measurements on single crystals of Tl2Ba2CuO6.
Nitrogen balance for two container-grown woody ornamental plants

Abstract The woody ornamentals Ilex opaca ‘Hedgeholly’ and Lagerstroemia×‘ Tonto ’ plants were grown in containers for 9 months, and fertilized with complete nutrient solutions differing in applied nitrogen ([N]A) concentration: 15, 30, 60, 120, 210, and 300 mg l−1. Shoot dry biomass and leaf area increased significantly with applied N concentrations up to 60 mg l−1, but higher levels caused significant reductions in these parameters. Root dry weights decreased with increases in applied N. Tissue N concentrations and leaf chlorophyll levels increased in a typical saturation response with N supply, and maximum dry weight yields for Ilex and Lagerstroemia plants were observed at leaf N concentrations of 2.53 and 2.65%, respectively. Plants of both species fertilized with 15–60 mg l−1 produced leachate N concentrations that were on average below the actual [N]A, whereas plants fertilized with 120–300 mg l−1 resulted in leachate N concentrations that were higher than [N]A. Across the two species, N leaching losses (as a fraction of total N applied) increased from an average of 17.4% in plants receiving 15 mg l−1 of N to an average of 52.0% for those fertigated with 210 and 300 mg l−1. The fraction of applied N that was taken up by plants in both species decreased significantly with increases in [N]A, averaging 46.8 and 7.2% for the 15 and 300 mg l−1 treatments, respectively. The N fraction retained by the growing medium at the end of the experiment was not significantly affected by [N]A, averaging 6.4 and 3.7% of the applied N in Ilex and Lagerstroemia, respectively. Interestingly, and regardless of [N]A, an average of 31% (range 22.8–40.6%) of the total applied N could not be accounted for at the end of the experiment in both species, and this fraction was attributed to gaseous N losses by denitrification.
Comparison of Sugar, Acids, and Volatile Composition in Raspberry Bushy Dwarf Virus-Resistant Transgenic Raspberries and the Wild Type ‘Meeker’ (Rubus Idaeus L.)

Raspberry bushy dwarf virus (RBDV) causes a significant reduction in yield and quality in raspberry and raspberry−blackberry hybrid. Genetic modifications were made to ‘Meeker’ red raspberries to impart RBDV resistance. The RBDV-resistant transgenic and wild type ‘Meeker’ plants were grown in Oregon and Washington, and the fruits were harvested in the 2004 and 2005 growing seasons. Year-to-year and site-to-site variations were observed for the °Brix and titratable acidity, with Oregon raspberries having slightly higher °Brix and lower titratable acidity than Washington raspberries. Twenty-nine volatile compounds were quantified using stir bar sorptive extraction (SBSE) paired with gas chromatography−mass spectrometry (GC-MS). There were very few differences in volatile concentrations between the transgenic varieties and the wild type ‘Meeker’. Much larger variations were observed between sites and harvest seasons. Raspberries grown in Oregon appeared to have higher concentrations of δ-octalactone, δ-decal...
Stratospheric Hydroperoxyl Measurements

The hydroperoxyl radical plays a key role in stratospheric chemistry through the HO(x) catalytic cycle of ozone destruction. Earlier measurements of stratospheric HO2 have given mixed results. Some measured mixing ratios greatly exceed theoretical predictions. Measurements of HO2 have now been made with a balloon-borne FIR spectrometer. The measured daytime profile is in excellent agreement with theory up to 40 kilometers. Above this level the measurements exceed theory by 30 percent, perhaps because of underprediction of ozone at these altitudes. The nighttime HO2 profile is strongly depressed with respect to the daytime profile, in general agreement with theory.
Octahedral [TpRu(PMe3)2OR]n+ Complexes (Tp = hydridotris(pyrazolyl)borate; R = H or Ph; n = 0 or 1): Reactions at Ru(II) and Ru(III) Oxidation States with Substrates that Possess Carbon-Hydrogen Bonds

The Ru(II) complexes TpRu(PMe3)2OR (R = H or Ph) react with excess phenylacetylene at elevated temperatures to produce the phenylacetylide complex TpRu(PMe3)2(C⋮CPh). Kinetic studies indicate that the reaction of TpRu(PMe3)2OH and phenylacetylene likely proceeds through a pathway that involves TpRu(PMe3)2OTf as a catalyst. The reaction of TpRu(PMe3)2OH with 1,4-cyclohexadiene at elevated temperature forms benzene and TpRu(PMe3)2H, while TpRu(PMe3)2OPh does not react with 1,4-cyclohexadiene even after 20 days at 85 °C. The paramagnetic Ru(III) complex [TpRu(PMe3)2OH][OTf] is formed upon single-electron oxidation of TpRu(PMe3)2OH with AgOTf. Reactivity studies suggest that [TpRu(PMe3)2OH][OTf] initiates reactions, including hydrogen atom abstraction, with C−H bonds that have bond dissociation energy < 80 kcal/mol. Experimentally, the O−H bond strength of the Ru(II) cation [TpRu(PMe3)2(OH2)][OTf] is estimated to be between 82 and 85 kcal/mol, while computational studies yield a BDE of 84 kcal/mol, which are ...
Removing Batch Effects From Histopathological Images for Enhanced Cancer Diagnosis

Researchers have developed computer-aided decision support systems for translational medicine that aim to objectively and efficiently diagnose cancer using histopathological images. However, the performance of such systems is confounded by nonbiological experimental variations or “batch effects” that can commonly occur in histopathological data, especially when images are acquired using different imaging devices and patient samples. This is even more problematic in large-scale studies in which cross-laboratory sharing of large volumes of data is necessary. Batch effects can change quantitative morphological image features and decrease the prediction performance. Using four batches of renal tumor images, we compare one image-level and five feature-level batch effect removal methods. Principal component variation analysis shows that batch is a large source of variance in image features. Results show that feature-level normalization methods reduce batch-contributed variance to almost zero. Moreover, feature-level normalization, especially ComBatN, improves cross-batch and combined-batch prediction performance. Compared to no normalization, ComBatN improves performance in 83% and 90% of cross-batch and combined-batch prediction models, respectively.