cssi/SciSciGPT-SciSciNet huggingface dataset:
The Effect of Early Head Start on Child Welfare System Involvement: A First Look at Longitudinal Child Maltreatment Outcomes

The high societal and personal costs of child maltreatment make identification of effective early prevention programs a high research priority. Early Head Start (EHS), a dual generational program serving low-income families with children prenatally through age three years, is one of the largest federally funded programs for infants and toddlers in the United States. A national randomized trial found EHS to be effective in improving parent and child outcomes, but its effectiveness in reducing child maltreatment was not assessed. The current study used administrative data from state child welfare agencies to examine the impact of EHS on documented abuse and neglect among children from seven of the original seventeen programs in the national EHS randomized controlled trial. Results indicated that children in EHS had significantly fewer child welfare encounters between the ages of five and nine years than did children in the control group, and that EHS slowed the rate of subsequent encounters. Additionally, compared to children in the control group, children in EHS were less likely to have a substantiated report of physical or sexual abuse, but more likely to have a substantiated report of neglect. These findings suggest that EHS may be effective in reducing child maltreatment among low-income children, in particular, physical and sexual abuse.
The determination of state-space representations for linear multivariable systems

A new, relatively simple, constructive method is presented for obtaining state-space or normal form representations for linear, time invariant systems whose dynamics are expressed in a more general matrix differential operator form. The development employed provides new insight into various structural properties of linear systems. Equivalence is defined for a rather large class of linear systems, and an algorithm is given for reducing any member of this class to normal form. In order to outline the algorithm, a number of ''well known'' results involving polynomial matrices are employed for the first time, along with the ''structure theorem''. An example is used to illustrate the algorithm and two appendices are employed to clarify the development.
Decay Scheme, Spin, and Magnetic Moment of 20-min K 45

We have studied 20-min ${\mathrm{K}}^{45}$ and its decay using a lithium-drifted germanium detector and also by means of the atomic-beam magnetic-resonance method. The $\ensuremath{\gamma}$-ray studies revealed a new state in ${\mathrm{Ca}}^{45}$ at 1883(3)-keV excitation; the now-measured spin of ${\mathrm{K}}^{45}$ and other evidence indicate that this is a $1{d}_{\frac{3}{2}}$ hole state. The atomic-beam studies yielded $I=\frac{3}{2}$ for ${\mathrm{K}}^{45}$ and a value for the zero-field hyperfine structure separation $\ensuremath{\Delta}\ensuremath{\nu}=204.5873(15)$ Mc/sec. From this we calculate the nuclear magnetic-dipole moment to be $|{\ensuremath{\mu}}_{I}|=0.1734(4)$ nm (diamagnetically corrected). A calculation based on a model which describes ${\mathrm{K}}^{39}$ through ${\mathrm{K}}^{43}$ with considerable accuracy gives the result ${\ensuremath{\mu}}_{I}=+0.218$ nm. Further calculation yields satisfactory values for the binding energies of ${\mathrm{K}}^{44}$ through ${\mathrm{K}}^{47}$.
Volume Targeted Patient Triggered Ventilation: Decreased Subject Effort and Improved Efficiency in an Animal Model of Respiratory Distress Syndrome|[dagger]| 1611

We hypothesized that a fully-synchronized patient triggered mode of ventilation, assist-control (A/C), would reduce subject effort when compared to IMV and SIMV. Ten newborn piglets (1.9±0.40 kg) with saline lavage-induced lung injury (PaO2<100 torr at FiO2 1.0) were randomized to sequential 30 minute periods of IMVSIMVAC (n=5), or ACSIMVIMV (n=5) using time-cycled, pressure limited, volume targeted (15 mL/kg) ventilation (Drager Babylog®). Respiratory rate(RR) and minute ventilation (Ve) were determined as 1 minute moving averages every 15 seconds; tidal volume (Vt), mean airway pressure (MAP), and an esophageal pressure-time index (PE·RR) to estimate subject, not mechanical, work of breathing were determined for all breaths. PE·RR was defined as the area below baseline of the esophageal pressure-time curve× RR, and was recorded using a computer-assisted lung mechanics analyzer(VenTrak®). Blood gases were recorded every 30 seconds using an in-line continuous blood gas analyzer (Paratrend 7®); a/A was calculated. Vt variation was assessed using the coefficient of variation (V; SD/mean × 100). Data analysis used paired t-tests with Bonferroni correction. Wilcoxon rank-sum test was used for nonparametric data.Results: Subject work, estimated by PE·RR, was significantly lower with A/C. Statistically significant differences in A/C vs IMV and SIMV included higher pH, lower RR, and increased Ve and MAP. No differences in a/A were seen. Vt was always less variable during A/C. Conclusion: Fully-synchronized A/C ventilation produced the highest Ve and pH, and the most consistent Vt, with the lowest subject effort as estimated by PE·RR. This data suggests A/C is more efficient during spontaneous respiration than either IMV or SIMV, as it provides improved gas exchange with less inspiratory effort, Table
Interactions between serum titres to filamentous bacteria and their relationship to human periodontal disease.

Abstract Sera from patients with localized gingivitis and periodontitis were examined by indirect immunofluorescence for antibodies to strains of Actinomyces israelii. Actinomyces naeslundii, Bacterionema matruchotii, Eubacterium saburreum, Leptotrichia buccalis and an unidentified filament. Antibodies to three or more strains of differing genera were present in all sera, but the titres to the individual microorganisms varied widely both within and between subjects. Antibody responses to some microorganisms were greater than or dominant to responses to other microorganisms, both in terms of consistency of response in all subjects tested and in the titres. This dominance of antibody response to some microorganisms was found in comparisons made across genera, across species, and even between strains within currently recognized species. Both simple and complex relationships in titre were found between antibody responses to two, three and four different microorganisms, but significant relationships were not found between intra-species isolates. The incidence of high-titre sera was significantly greater from periodontitis than from gingivitis patients. However, differential diagnosis between the two classes of periodontal disease could not be made reliably on the basis of specific serum titres to either individual or pairs of microorganisms because of variability in titre within each class of subjects.
Tyrosine Hydroxylase Regulation: Apparent Kinetic Alterations Following Incubation of Brain Slices in a Sodium‐free Medium

In an attempt to determine if alterations in intraneuronal Ca2+ may regulate tyrosine hydroxylase activity, brain slices were subjected to experimental manipulations known to increase the intraneuronal concentration of free Ca2+ ions. Incubation of either striatal or olfactory tubercle slices in a Na+-free medium for 15 min at 37 degrees resulted in a marked increase in the activity of tyrosine hydroxylase present in the 20,000 g supernatant fraction of homogenates prepared from the slices. Tyrosine hydroxylase isolated from slices previously incubated in a Na+-free, choline-enriched medium or in a Na+-free, sucrose-enriched medium exhibited maximal activities when assayed at pH 6.0 and 7.0, respectively. However, the percentage stimulation of enzyme activity induced by incubation of the slices in a Na+-free medium was maximal when the enzyme assays were performed at pH 7.0. The observed increase in enzyme activity seems to be mediated by a decrease in the apparent Km of the enzyme for pteridine cofactor, regardless of whether the kinetic enzyme analyses were conducted at pH 6.0 or 7.0, and by an increase in the Ki of the enzyme for end-product inhibitor dopamine. The apparent kinetic changes in the enzyme do not seem to result from alterations in the endogenous dopamine content of the slices, and they are independent of any increase in dopamine release that might have occurred as a response to the augmented intraneuronal Ca2+ concentration. Furthermore, the activation of tyrosine hydroxylase produced by incubating slices in a Na+-free medium is observed even in slices depleted of dopamine by pretreatment of rats with reserpine 90 min before preparation of brain slices. The activation of tyrosine hydroxylase observed under these experimental conditions does not seem to be mediated by cAMP or by a cAMP-dependent phosphorylation process. It is suggested that the changes in tyrosine hydroxylase reported are mediated primarily by a rise in the free Ca2+ concentration within the nerve tissue. These observations are consistent with the hypothesis that the kinetic activation of tyrosine hydroxylase produced after depolarization of central dopaminergic neurons may occur through a Ca2+-dependent even other than transmitter release.
The effect of non-contingent negative and positive reinforcement operations on the acquisition of superstitious behaviors.

Abstract The differential effects of non-contingent positive and negative reinforcement operations on the acquisition of superstitious behaviors and rules were investigated in two experiments. College students were instructed to try to produce and/or keep the word “GOOD” on a computer screen (positive reinforcement), or to try to prevent and/or remove the word “BAD” from the screen (negative reinforcement) using response keys. Data from both experiments indicated that participants exposed to lean schedules of negative reinforcers believed that they had greater control over non-contingent stimulus events than participants exposed to either rich or lean schedules of positive reinforcers. These findings and results from research investigating everyday superstitious activities suggest that, relative to positive reinforcement, negative reinforcement operations may provide a more fertile condition for the development and maintenance of superstitious behaviors.
Documenting digital images: Textual meta‐data at the Blake Archive

As libraries continue to acquire and develop collections based in digital media, they face a corresponding need to document the electronic data comprising such collections. By documentation I mean the provision of contextual information pertaining to the source, creation, processing, and current state of a digital object. When dealing with electronic text, documentation is often instinctive and unproblematic, at least in a technical sense, given that the data and its documentation (or meta‐data) both share the same medium: one documents textual data by supplementing it with more textual data (the header employed by the Text Encoding Initiative is exemplary in this regard). When libraries create digital image collections, however, documentation becomes more problematic. Even if an image is surrounded by a robust network of supporting materials, the functionality of client‐server networks such as the World‐Wide Web permits the image to become detached from its documentary apparatus. Every image encountered on the Web, is cached, at least temporarily, on the viewer's hard drive. Documentary information that is merely presented ‘alongside’ an image is left behind at that point, as it also is should the viewer choose to save a copy of the image for future reference. Given those circumstances — which are paralleled in such media as sound or video — the issue of providing reliable documentary meta‐data for non‐textual electronic files is a crucial one for digital library development. In what follows, I will present the solution adopted at the William Blake Archive, a large‐scale electronic editing project in which images — and not text — are the focal point.
A survey of pulp and paper mill effluents for their potential to induce mixed function oxidase enzyme activity in fish

Abstract The potential of 31 secondary-treated pulp and paper mill effluents from eight different mills to induce mixed function oxidase (MFO) activity, in the liver of rainbow trout (Oncorhynchus mykiss), was investigated by short-term (4-day) laboratory exposures to 10% effluent concentration. Two of six thermomechanical pulp (TMP) mill effluents investigated caused increased EROD activity while there was no increase caused by the two chemi-thermomechanical pulp (CTMP) mill effluents tested. In contrast, with one exception, EROD activity was significantly induced as a result of exposure to bleached as well as unbleached kraft mill effluents. The replacement of chlorine in the bleaching of kraft pulp by chlorine dioxide or non-chlorine containing compounds (such as peroxide) did not eliminate the final mill effluent's ability to induce EROD activity. Rather, the kraft cooking process used to convert wood into pulp may itself be a source of MFO-inducing substances.
Abstract 2339: Specific binding of modified ZD 6474 (Vandetanib) monomer and its dimer with VEGF receptor 2

Introduction: Tumor angiogenesis is an important component of cancer biology driven in part by the thesis that tumor vessel growth is a necessary requirement for tumor growth. Angiogenesis does not only depend on endothelial cell invasion and proliferation: it also requires pericyte coverage of vascular sprouts for vessel stabilization. These processes are coordinated by vascular endothelial growth factor (VEGF). A significant portion of research on tumor angiogenesis has focused on VEGF and its blockage with the expectation that dramatic results would be demonstrated in cancer patients as previously documented in animal models. Vandetanib, also known as ZD6474, is an antagonist of the vascular endothelial growth factor (VEGF) receptor-2 (VEGFR-2) and the epidermal growth factor receptor (EGFR or HER1 or ErbB1). It is an orally bioavailable small molecule tyrosine kinase inhibitor of multiple growth factors, and is now available in the US for the treatment of metastatic medullary thyroid cancer (MTC). Methods: ZD 6474 monomer was purchased modified to add a fluorescent dye (6-FAM). Its coupled ZD 6474 dimer was also prepared using a PEG linker, similarly with FAM fluorescent dye. The two compounds were compared in a series of in vitro studies using human endothelial cell (HUVECs) and several cancer cell lines. We first looked at VEGFR binding affinity and specificity with cell uptake and blocking study. Then, the effects on cellular viability and angiogenesis were compared using with tubular formation of HUVECs in vitro, also matrigel plug assay, and bio-distribution test on VEGF over expressed U87 human glioma tumor model in vivo. Results: Imaging of ZD 6474 dimer showed much better binding and uptake in HUVECs and other VEGFR expressing cells than ZD 6474 monomer, including during systemic delivery to tumors. However, the therapeutic and anti-angiogenic effects were mixed, with most tests showing the dimer to have same or weaker effects than the monomer. Conclusion: This study provides a rational for the evaluation of dimeric ZD 6474 as a potential imaging agent. Paradoxically, it also demonstrates that the enhanced receptor binding achieved by multivalency does not always translate into enhanced therapeutic effectiveness. Keyword: Vandetanib (ZD 6474), anti-angiogenesis, VEGFR Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2339. doi:1538-7445.AM2012-2339
A high-performance fast Fourier transform algorithm for the Cray-2

Most implementations of a radix-2 fast Fourier transform on large scientific computers use algorithms that involve memory accesses whose strides are powers of two. (The term stride means the memory increment between successive elements stored or fetched.) Such strides are unacceptable for recently developed supercomputers, particularly the Cray-2, because of serious difficulties with memory bank conflicts.
Efficiency of Synthetic Retrospective Studies

In many large cohort studies of association between a disease and a concommitant variable, only a small fraction of subjects develope the disease. Substantial computational expense can be avoided by restricting the analysis to the diseased cases and a random sample of disease-free controls. This paper examines the efficiency of such synthetic retrospective designs relative to that of the full cohort analysis when the association is studied using the logistic or proportional hazards model. Within this context the efficiencies of matched vs. unmatched designs are also examined.
Photophysical Characterization of a Ruthenium(II) Tris(2,2′-bipyridine)-Doped Zirconium UiO-67 Metal–Organic Framework

The photophysical properties of ruthenium(II) tris(5,5′-dicarboxy-2,2′-bipyridine), RuDCBPY, doped into the metal organic framework of Zr6O4(OH)4(BPDC)6, RuDCBPY-UiO67 (where BPDC is 4,4′-biphenyldicarboxylic acid), are presented as a function of the degree of RuDCBPY doping. Steady-state diffuse reflectance of RuDCBPY-UiO67 powder shows an absorption maxima at 455 nm, which is effectively insensitive to doping concentration. The energy of the emission maxima and excited state lifetimes are, however, quite sensitive to concentration of RuDCBPY in UiO-67. At low doping concentrations, the emission maxima lies at ∼630 nm. The emission decay can be adequately modeled using a single discrete exponential decay function with an observed lifetime of 1.4 μs. The emission lifetime and the energy of the emission maxima are found to decrease with increased RuDCBPY concentration. However, at higher doping the emission decay becomes nonexponential. Equally adequate fits to the data were obtained using stretched expone...
Adaptive significance of communal oviposition in wood frogs (Rana sylvatica)

1. Wood frogs (Rana sylvatica) are one of the earliest anurans to breed in spring. Their breeding behavior is ‘explosive’, with most oviposition occurring within 2 to 6 days. Early breeding may reduce predation and ensure adequate developmental time for larvae, but it is accompanied by the risk of substantial egg mortality due to cold temperature. 2. Males amplex females throughout breeding ponds, and pairs move toward a communal oviposition site. Females usually deposit eggs on submerged twigs or vegetation directly contiguous to other egg masses. Late breeders oviposit at the edge of the growing clump, thus surrounding the egg masses of earlier breeders. 3. Egg masses in the center of a clump are insulated from thermal extremes in the surrounding water. Within a clump, central egg masses were warmer than peripheral egg masses, but egg masses at the edge of a clump were warmer than single egg masses deposited outside the clump. 4. Central egg masses had significantly greater hatching success than peripheral egg masses. Central egg masses also had significantly more eggs than peripheral egg masses, suggesting that larger females obtained central sites. 5. Because central egg masses have the greatest survivorship to hatching, wood frogs should be selected to breed early to obtain optimal oviposition sites. Breeding synchrony may result from this selection for early oviposition, with the ultimate limiting factors being how quickly frogs can emerge in the spring and when ice on ponds melts.
Modulation and Block of Ion Channels: A New Biology of Polyamines

Abstract The endogenous polyamines spermine, spermidine, and putrescine have effects on several types of cation channels. Intracellular polyamines, in particular spermine, contribute to intrinsic gating and rectification of strong inward rectifier K + channels. Intracellular spermine is also responsible for inward rectification of some types of Ca 2+ -permeable AMPA and kainate receptors. Spermine has a number of effects on the activity of the NMDA subtype of glutamate receptor, involving two or more extracellular polyamine binding sites on the NMDA receptor. In K + channels and glutamate receptors, some of the amino acids in the receptor/channel structure that influence sensitivity to polyamines have been identified, leading to a partial understanding of the effects of polyamines at a molecular level. Block of K + channels by intracellular polyamines is likely to be an important mechanism controlling the resting membrane potential and excitability in many cell types. Block of glutamate receptors by intracellular spermine and modulation by extracellular spermine may affect excitability and the influx of Ca 2+ in neurons and glial cells of the nervous system.
The historical evolution of PTSD diagnostic criteria: From freud to DSM-IV

The present study examined the evolution of the diagnostic criteria from the early writings of Sigmund Freud to the current DSM-IV. Freud's original model of neurosis, known as Seduction Theory, was a post-traumatic paradigm which placed emphasis on external stressor events. In 1897, due to a confluence of factors, he shifted his paradigm to stress intrapsychic fantasy as the focus of analytic treatment for traumatic neurosis. Freud's thinking influenced both the DSM-I and II classification of stress response syndromes as transient reactive processes. However, it is evident from his lectures in 1917–1918 that he understood the interrelatedness of what today is the four diagnostic categories in the DSM-IV.
Forming and scaffolding human coalitions with a multi-agent framework

With the advancement of teleconferencing technologies, human users are collaborating online more than ever today. To improve the efficiency and effectiveness of online human coalitions, one needs to support and facilitate collaborations among human users who may or may not know of each other well and of how to work well together as a team or in a team. Here we propose the Integrated Human Coalition Formation and Scaffolding (iHUCOFS) framework. This multiagent framework considers the roles of an agent as both an advisor and a representative to a human user, the tradeoffs between forming and scaffolding human coalitions, and how scaffolding could impact human behaviors for future coalitions. Based on the axioms and design principles of iHUCOFS, we have developed VALCAM---an iterative auction based coalition formation algorithm. To investigate the feasibility and impact of VALCAM, we have conducted an experiment in a computer-supported collaborative learning environment and obtained promising results.
Long-term gain variation in the FUSE detectors

The Far Ultraviolet Spectroscopic Explorer (FUSE) satellite has been in orbit and collecting scientific data since mid-1999. The FUSE detector system contains two large-format microchannel plate detectors with double delay line anodes. Both detectors have performed well since the beginning of the mission, but as they have aged their gain characteristics have changed. Variations in the amount of charge extracted as a function of position on the detector has caused time- and wavelength-dependent changes to the detector performance; corrections for these effects must be applied to the data in the science data pipeline in order to minimize the introduction of artifacts into the calibrated spectra. The gain characteristics of the detectors and the ways in which they have changed since launch are discussed, as are mitigation strategies in both the use of the detectors and the interpretation of the data.
Practice effects in frequency discrimination by hearing impaired children.

The difference limens for frequency (DLF) at 250 and 500 Hz of 23 deaf and 21 hard-of-hearing children were measured in three practice sessions. Conditions included both fixed amplitude, where loudness could be confounded with pitch, and variable amplitude, where loudness and pitch varied independently. Results indicated: (1) The deaf group showed a significant decrease in size of DLF over the three test sessions. The hard-of-hearing group showed a significant decrease in size of DLF over the three test sessions for only one condition. A third group of children with normal sensitivity showed asymptotic performance on the first test session. (2) A moderate correlation between Hearing Level and size of DLF was found at 500 Hz but not at 250 Hz. (3) Significant differences in performance were found between the fixed- and variable-amplitude conditions. The reliability and the validity of the results are discussed and some implications for teachers of the deaf are mentioned.
COMPARATIVE PROTEIN STUDIES (KJELDAHL, DYE BINDING, AMINO ACID ANALYSIS) OF NINE STRAINS OF Agaricus bisporus (Lange) IMBACH MUSHROOMS

Although it is difficult to ascertain the true protein content of mushrooms because of their variable nonprotein nitrogen content and protein heterogeneity, even among strains within a species, some knowledge about a mushroom's protein is essential for nutritional, processing and economic considerations. Protein similarities and differences in cultivated mushrooms are shown with the aid of three analytical methods. Protein data based on amino acid analyses are preferred but too expensive to obtain. Amido black dye binding is the next preferable method. Its correlation with amino acid protein was higher (D.74) than that between Kjeldahl protein and amino acid protein (D.44).
Essential hand surgery procedures for mastery by graduating orthopedic surgery residents: a survey of program directors.

Purpose To establish the essential hand surgery procedures that should be mastered by graduating orthopedic surgery residents. This framework can then be used as a guideline for developing an Objective Structured Assessment of Technical Skill to teach and document technical skill in hand surgery. Methods A select group of 10 expert hand surgeons was surveyed regarding the essential hand surgery procedures that should be mastered by graduating orthopedic surgery residents. The top 10 procedures from this survey were then used to survey all 155 American Council of Graduate Medical Education–approved orthopedic surgery program directors regarding the essential procedures that should be mastered by graduating orthopedic surgery residents. Results We had a 39% response rate to the program director survey. The top 8 hand surgery procedures as determined by the orthopedic surgery program directors included open carpal tunnel release, open A1 pulley release, open reduction internal fixation of distal radius fracture, flexor tendon sheath steroid injection, excision of dorsal or volar ganglion, closed reduction and percutaneous pinning of metacarpal fracture, open cubital tunnel release, and incision and drainage of flexor tendon sheath for flexor tenosynovitis. Conclusions Surgical educators need to develop objective methods to teach and document technical skill. The Objective Structured Assessment of Technical Skill is a valid method to accomplish this task. However, there has been no consensus regarding which hand surgery procedures should be mastered by graduating orthopedic surgery residents. We have identified 8 procedures that were overwhelmingly supported by orthopedic surgery program directors. These 8 procedures can be used as a guideline for developing an Objective Structured Assessment of Technical Skill to teach and document technical skill in hand surgery. Clinical relevance This study addresses the future of orthopedic surgery education as it pertains to hand surgery.
Cognitive and interpersonal abilities related to the primary activities of R&D managers

Abstract This study attempted to identify the primary activities performed by R&D managers at different supervisory levels, and the cognitive and interpersonal ability requirements that underlie these activities. A task inventory containing 244 managerial tasks was completed by 117 R&D managers in nine organizations. The 48 tasks which managers rated as having spent the most time were factor analyzed, resulting in the identification of three primary activities: project management, personnel supervision, and strategic planning. Furthermore, these activities varied with supervisory level, with R&D managers performing a wider range of these activities with the progression from first-line to upper-level management. Thirty R&D managers later rated the degree to which 19 cognitive and interpersonal abilities were required for performing these primary activities. Strategic planning was rated as requiring significantly higher levels of oral expression, logical reasoning, originality, fluency of ideas, oral defense, and resistance to premature judgement than was required for the other two primary activities. Personnel supervision required a higher level of social sensitivity than was required for the other two activities. Project management required high levels of information ordering, oral fact- finding ability, problem sensitivity, and oral and written comprehension. Implications of the findings for understanding R&D managerial performance and personnel staffing functions are discussed.
Subcutaneous compliance and gravitational adaptation in snakes

Previous studies have implicated morphological adaptations as important counter-measures to gravitational stresses on the circulatory systems of arboreal or climbing snakes. Such features include tight skin and relatively non-compliant tissue compartments that oppose edema formation, but these traits have not been previously studied quantitatively. To provide information on this subject, interstitial fluid pressures were measured in eleven species of snakes using slit-end catheters positioned in subcutaneous tissue located at the base of the tail. Interstitial pressures in all species were typically 0 to +2 mm Hg in normally hydrated tissue, but varied widely when snakes were active or when the tail was curved at the site of measurement. Local compliance of the free fluid space was determined from measurements of pressure while saline was infused via the catheter tip. Such measurements varied from 0.18 microliters/mm Hg in Philodryas baroni, an arboreal species, to 2.3 microliters/mm Hg in Crotalus adamanteus, a ground-dwelling, terrestrial species. In general, compliance of the subcutaneous tissue space was greatest (P < 0.05) in non-climbing and aquatic species of snakes that do not face problems of gravitational edema in dependent tissues. Presumably, the compliance measurements reflect adaptive structural differences related to requirements for counteracting gravitational stresses in the various species.
Determinants of gender in Jack-in-the-pulpit; the influence of plant size and reproductive history

Jack-in-the-pulpit, Arisaema triphyllum, is a perennial forest herb with the ability to change sex. At two sites in upstate New York, plant sex was correlated with plant size: males were smaller than females, nonflowering plants were smaller than males. Changes in plant size were accompanied by changes in sex. Sex change occurred quite frequently; at one site, 8% of nonflowering plants, 64% of males, and 63% of females changed their sex from one season to the next. The probability that a plant will change size and sex between years was altered by artificial defoliation and by the production of seeds, but was not affected by supplementing plants with nutrient fertilizer. Discriminant analysis indicated that several historical factors significantly affected plant sex: a model including the variables of current plant size, previous year's plant size, and previous year's sex was significantly better at predicting the current sex of individuals than was a model containing only current plant size. However, even the consideration of these three variables left up to a third of the plants misclassified with respect to gender. This analysis explains in part why plants at the two sites changed sex at different sizes, but it is likely that other factors-e.g. genetic differences-are involved.
Cetyltrimethylammonium bromide polyacrylamide gel electrophoresis: estimation of protein subunit molecular weights using cationic detergents.

Abstract Polyacrylamide gel electrophoresis in the presence of the cationic detergent, cetyltrimethylammonium bromide (CTAB), has been previously used to obtain more accurate estimates of the molecular weight of certain highly charged and membrane protein subunits that exhibit anomalous electrophoretic behavior in the presence of sodium dodecyl sulfate (SDS). The improved method reported herein is comparable to the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE) method in simplicity, time, and quality of gels, but the CTAB-PAGE method appears to have a wider range of application for diverse types of proteins. The technique may also be used for verification of molecular weight data and thus detection of possible anomalous results obtained using the anionic SDS-PAGE method. The described method eliminates the precipitates formed between ammonium persulfate and cationic detergents during gel polymerization and between cationic detergents and the protein dyes during staining that have complicated previous methods. The reliability of the technique is indicated by the high correlation coefficient (−0.97) between R f and molecular weight. Data are presented to indicate that the method can be used to estimate the subunit molecular weight of unknown proteins with a 95% level of confidence.
Direct Interactions of Runx2 and Canonical Wnt Signaling Induce FGF18

Canonical Wnt signaling is clearly required for skeletal development and bone formation. However, the targets of Wnt signaling that convert this signal into bone are unclear. Identification of these targets will yield insight into normal bone physiology and suggest new therapeutics for treatment of bone disease. Here we show that an essential regulator of bone development, FGF18, is a direct target of canonical Wnt signaling. A single DNA binding site for the Wnt-dependent transcription factors TCF/Lef accounted for the stimulation of the fgf18 promoter in response to Wnt signaling. Additionally, targeted disruption of betacat blocked fgf18 expression in vivo. Partially overlapping the TCF/Lef binding site is a Runx2 binding site and experiments showed that Runx2 and TCF/Lef work cooperatively to induce fgf18 expression. RNA interference knockdown of Runx2 inhibited and Runx2 forced expression augmented the induction of fgf18 by canonical Wnt signaling. Significantly, Runx2 formed a complex with Lef1 or TCF4 and this complex bound the composite binding site in the fgf18 promoter. These results demonstrate that two transcription pathways that are essential for bone, physically and functionally converge at the fgf18 promoter.
Nuclear Localization and Transcriptional Repression Are Confined to Separable Domains in the Circadian Protein CRYPTOCHROME

Abstract Circadian rhythms are driven by molecular clocks composed of interlocking transcription/translation feedback loops [1, 2]. CRYPTOCHROME (CRY) proteins are critical components of these clocks [3, 4] and repress the activity of the transcription factor heterodimer CLOCK/BMAL1 [5–7]. Unlike the homologous DNA repair enzyme 6-4 PHOTOLYASE, CRYs have extended carboxyl-terminal tails and cannot repair DNA damage (reviewed in [8]). Unlike mammals, Xenopus laevis contains both CRYs (xCRYs) and 6-4 PHOTOLYASE (xPHOTOLYASE), providing an excellent comparative tool to study CRY repressive function. We can extend findings to CRYs in general because xCRYs share high sequence homology with mammalian CRYs [9]. We show here that deletion of xCRYs' C-terminal domain produces proteins that are, like xPHOTOLYASE, unable to suppress CLOCK/BMAL1 activation. However, these truncations also cause the proteins to be cytoplasmically localized. A heterologous nuclear localization signal (NLS) restores the truncation mutants' nuclear localization and repressive activity. Our results demonstrate that the CRYs' C termini are essential for nuclear localization but not necessary for the suppression of CLOCK/BMAL1 activation; this finding indicates that these two functions reside in separable domains. Furthermore, the functional differences between CRYs and PHOTOLYASE can be attributed to the few amino acid changes in the conserved portions of these proteins.
An in vitro assay for monitoring prenyl transferase activity in lepidopteran corpora allata

The prenyl-transferase, farnesyl pyrophosphate (FPP) synthase, which catalyzes the head-to-tail couplings of dimethylallyl pyrophosphate (DMAPP) and geranyl pyrophosphate (GPP) with isopentenyl pyrophosphate (IPP), is a key enzyme in juvenile hormone (JH) biosynthesis. While moderate FPP synthase activity has been found in whole-body insect preparations, enzymatic activity in the corpus allatum, the gland responsible for JH biosynthesis, has been elusive. A new procedure for examining corpora allata prenyl transferase activity in the lepidopteran Manduca sexta is described. In contrast to most other short-chain prenyl transferases, the larval enzyme requires detergent for activity. Optimum conversion of DMAPP and GPP to FPP is obtained with corpora allata homogenates containing 2% Triton X-100, 0.15% bovine serum albumin, and 25% glycerol. The enzyme is activated in the presence of Mn 2+ or Mg 2+ and is inactivated by the addition of N-ethylmaleimide.
Systems analysis of biological networks in skeletal muscle function

Skeletal muscle function depends on the efficient coordination among subcellular systems. These systems are composed of proteins encoded by a subset of genes, all of which are tightly regulated. In the cases where regulation is altered because of disease or injury, dysfunction occurs. To enable objective analysis of muscle gene expression profiles, we have defined nine biological networks whose coordination is critical to muscle function. We begin by describing the expression of proteins necessary for optimal neuromuscular junction function that results in the muscle cell action potential. That action potential is transmitted to proteins involved in excitation–contraction coupling enabling Ca2+ release. Ca2+ then activates contractile proteins supporting actin and myosin cross-bridge cycling. Force generated by cross-bridges is transmitted via cytoskeletal proteins through the sarcolemma and out to critical proteins that support the muscle extracellular matrix. Muscle contraction is fueled through many proteins that regulate energy metabolism. Inflammation is a common response to injury that can result in alteration of many pathways within muscle. Muscle also has multiple pathways that regulate size through atrophy or hypertrophy. Finally, the isoforms associated with fast muscle fibers and their corresponding isoforms in slow muscle fibers are delineated. These nine networks represent important biological systems that affect skeletal muscle function. Combining high-throughput systems analysis with advanced networking software will allow researchers to use these networks to objectively study skeletal muscle systems. WIREs Syst Biol Med 2013, 5:55–71. doi: 10.1002/wsbm.1197 For further resources related to this article, please visit the WIREs website.
An investigation of possible causes of the holes in the condensational Venus cloud using a microphysical cloud model with a radiative-dynamical feedback

Near-infrared observations of the nightside of Venus reveal regions of high brightness temperatures. These regions of high brightness temperatures are caused by the localized evaporation of the middle and lower cloud decks, which are about 50 to 60 km above the surface of the planet. We simulate the Venus condensational middle and lower cloud deck with the University of Colorado/NASA Ames Community Aerosol and Radiation Model for Atmospheres (CARMA). Our simulated clouds have similar characteristics to the observed Venus clouds. Our radiative transfer model reproduces the observed temperature structure and atmospheric stability structure within the middle cloud region. A radiative-dynamical feedback occurs which generates mixing due to increased absorption of upwelling infrared radiation within the lower cloud region, as previously suggested by others. We find that localized variations in temperature structure or in sub-grid scale mixing cannot directly explain the longevity and optical depth of the clouds. However, vertical motions are capable of altering the cloud optical depth by a sufficient magnitude in a short enough timescale to be responsible for the observed clearings.
Towards better affect detectors: effect of missing skills, class features and common wrong answers

The well-studied Baker et al., affect detectors on boredom, frustration, confusion and engagement concentration with ASSISTments dataset were used to predict state tests scores, college enrollment, and even whether a student majored in a STEM field. In this paper, we present three attempts to improve upon current affect detectors. The first attempt analyzed the effect of missing skill tags in the dataset to the accuracy of the affect detectors. The results show a small improvement after correctly tagging the missing skill values. The second attempt added four features related to student classes for feature selection. The third attempt added two features that described information about student common wrong answers for feature selection. Result showed that two out of the four detectors were improved by adding the new features.
An investigation of the near-field wake behind a full-scale test aircraft

Three-dimensional velocity field measurements were made on three transverse measurement planes located at 7.7,33.3, and 61.2 in. behind the inboard-wing trailing edge of an aircraft in flight. The test aircraft was an L-19 modified to incorporate a distributed suction boundary-layer control system. Test data were obtained at various lift coefficients and with both zero and full flap deflections. Flowfield measurements were made with a totalvector hot-film probe mounted to a boom and traversing mechanism attached to the rear fuselage of the test aircraft. The velocity measurements allowed computation of all three components of vorticity at the 7.7-in. plane and the normal (to the measurement plane) component of vorticity at the other two planes. The test results are presented as a series of contours of the various vorticity component values in the measurement planes. A typical set of axial velocity contours has also been provided. The plotted contours show a reproducible set of features, which are always associated with the formation of a concentrated core of axial vorticity. The test data are also compared to the predictions of a two-dimensional inviscid wake calculation based on measured wing loading for the L-19.
A TWIN RESEARCH PERSPECTIVE ON READING AND SPELLING DISABILITIES

A review of twin research on reading and spelling disabilities fulfills two key functions: First, the special educational and developmental concerns of twins are highlighted. Second, the value of twin studies for investigating genetic and environmental factors underlying learning disabilities in a variety of cognitive domains is demonstrated. The discussion is introduced by a review of biological aspects of twinning and descriptions of twin research designs. Findings from twin studies that have addressed the unique educational circumstances, and the genetic effects of multiple‐birth children, on reading and spelling difficulties are then summarized. These findings are considered with reference to the professional activities of teachers and specialists in reading and language skills. Resources for assisting exceptional twin children are listed.
Thrombosis in vasculitis

Thrombo-embolic disease is an increasingly recognised complication of several vasculitides. A common observation is that thrombo-embolic complications coincide with periods of increased vasculitis disease activity, but the mechanism through which this happens is still unknown. Thrombo-embolic disease has been recognised for decades as a significant contributor to the morbidity and mortality of Behcet's disease, and the role of anticoagulation in its management is being minimised in favour of immunosuppression, although evidence from randomised controlled trials is lacking. Ancillary data from a randomised clinical trial and retrospective observational studies have confirmed an association between venous thrombo-embolic disease and vasculitides associated with anti-neutrophil cytoplasmic antibodies (ANCAs). An increased cardiovascular risk is now also recognised for vasculitides associated with ANCAs. Thrombosis plays a prominent role in the pathogenesis of thromboangiitis obliterans (Buerger's disease). The association of thrombosis with other vasculitides such as giant-cell arteritis and levamisole-induced vasculopathy is under investigation.
Gender differences in motivations for course selection: Academically talented students in an intensive summer program

This study examines the motivational factors contributing to course selection in a sample of students enrolled in an intensive three-week academic experience for exceptionally talented adolescents. Our sample included 947 gifted adolescents, of whom 3.7% were Black, 73.5% were White, 2.2% Hispanic, 0.1% Native American, 19.8% Asian, and 0.6% categorized themselves as “other.” Girls and boys selected different types of classes, with course participation falling along traditional gender-stereotyped lines. Boys and girls both performed exceptionally well, and said they chose their course because the subject was interesting, useful for future goals, and challenging. Females more often than males enrolled in classes because they perceived them as challenging, different from usual, not offered at school, and as making them more well-rounded. Males more often than females tended to select classes because they thought they would do well and/or because they viewed these classes as being useful for future schooling or career. However, these gender differences varied by the type of course the students took. The resulting complex picture of students' motivations is discussed in terms of the need to specify both the contexts in which males and females make their academic choices, and the interactive determinants of their motivations.
Antibiotic-coated hemodialysis catheters for the prevention of vascular catheter–related infections: a prospective, randomized study ☆

Abstract Purpose To determine the efficacy of minocycline-rifampin–coated hemodialysis catheters in reducing catheter-related infections in patients requiring hemodialysis for acute renal failure. Methods Between May 2000 and March 2002, 66 patients were randomly assigned to receive a minocycline-rifampin–impregnated central venous catheter and 64 were randomly assigned to receive an unimpregnated catheter. Patients were followed prospectively until the catheter was removed. Catheter-related infection was determined through quantitative catheter cultures, quantitative blood cultures, or both. Results Both groups of patients were similar in age, sex, underlying disease, type of dialysis (continuous vs. intermittent), neutropenia during catheterization and its duration, catheter insertion difficulties, and administration of blood products or medication. The mean (± SD) catheter dwell time was the same in both groups (8 ± 6 days, P = 0.7). There were seven catheter-related infections (11%), all associated with the use of unimpregnated catheters. Kaplan-Meier estimates for the risk of catheter-related infection showed that coated catheters were less likely to be associated with infection ( P = 0.006). Conclusion The use of polyurethane hemodialysis catheters impregnated with minocycline and rifampin decreases the risk of catheter-related infection in patients with acute renal failure.