2-Amino-5-nitro-N-[(E)-thio-phen-2-yl-methyl-idene]aniline.

In the title mol-ecule, C(11)H(9)N(3)O(2)S, the thio-phene and benzene rings form a dihedral angle of 17.68 (9)°. The thio-phene S atom and the imine N atom are syn with respect to each other.

Comparative studies on chitosan and polylactic-co-glycolic acid incorporated nanoparticles of low molecular weight heparin.

This study was performed to test the feasibility of chitosan and polylactic-co-glycolic acid (PLGA) incorporated nanoparticles as sustained-release carriers for the delivery of negatively charged low molecular weight heparin (LMWH). Fourier transform infrared (FTIR) spectrometry was used to evaluate the interactions between chitosan and LMWH. The shifts, intensity, and broadening of the characteristic peaks for the functional groups in the FTIR spectra indicated that strong interactions occur between the positively charged chitosans and the negatively charged LMWHs.

Bis(acetato-κO)bis-(4,5-dimethyl-benzene-1,2-diamine-κN)zinc.

The structure of the title compound, [Zn(CH(3)COO)(2)(C(8)H(12)N(2))(2)], has one half molecule in the asymmetric unit. The Zn(II) atom is situated on a twofold rotation axis and is tetrahedrally coordinated by two N and two O atoms. The crystal packing displays inter-molecular N-H⋯O hydrogen bonds and intra-molecular N-H⋯O and N-H⋯N hydrogen bonding.

Tropomodulin protects α-catenin-dependent junctional-actin networks under stress during epithelial morphogenesis.

α-catenin is central to recruitment of actin networks to the cadherin-catenin complex, but how such networks are subsequently stabilized against stress applied during morphogenesis is poorly understood. To identify proteins that functionally interact with α-catenin in this process, we performed enhancer screening using a weak allele of the C. elegans α-catenin, hmp-1, thereby identifying UNC-94/tropomodulin.

Rapid thermal equilibration of differentially heated protein and water in bovine corneal stroma.

We measure and simulate the thermal response of bovine corneal stroma to a picosecond IR heating pulse. A thermal diffusion model is developed for this tissue based on the spatial distribution and properties of protein and water constituents in the stroma. In this idealized model, differentially heated protein and water constituents thermally equilibrate with a thermalization time of 515 ps.

Substituent effect on the preferred DNA binding mode and affinity of a homologous series of naphthalene diimides.

A combination of isothermal titration calorimetry (ITC), topoisomerase I DNA unwinding assays, and ethidium bromide displacement studies were employed to investigate the binding of a homologous series of naphthalene diimides (NDI) to DNA. Our results suggest that the nature of the substituent plays a significant role in both the preferred binding mode and relative binding affinity of the compounds of this study. Only intercalative-type binding (K=15±3×10(6)M(-1)) was observed for the NDI with the smallest substituent (trimethyl-ethylamino), while larger members of the series (diethylmethyl-, dipropylmethyl- and dibutylmethyl-ethylamino substituents) adopted an additional binding mode of higher affinity (K(1)=31-78×10(6)M(-1)).

Mechanical testing of spider silk at cryogenic temperatures.

A method and results for mechanical testing of spider silk in extreme environments is presented. In particular, silk from the spider Steatoda triangulosa is harvested, and samples are subjected to cryogenic temperatures by means of liquid nitrogen submersion. Samples are destructively tested while immersed in liquid nitrogen, and the stress-strain characteristics are compared to those of silk at room temperature.

Microscopic investigation of reversible nanoscale surface size dependent protein conjugation.

Aβ(1-40) coated 20 nm gold colloidal nanoparticles exhibit a reversible color change as pH is externally altered between pH 4 and 10. This reversible process may contain important information on the initial reversible step reported for the fibrillogenesis of Aβ (a hallmark of Alzheimer's disease). We examined this reversible color change by microscopic investigations.

Substituent control of DNA binding modes in a series of chalcogenoxanthylium photosensitizers as determined by isothermal titration calorimetry and topoisomerase I DNA unwinding assay.

The DNA binding efficacy and preferred mode of binding of a series of rhodamine-related chalcogenoxanthylium dyes was investigated by isothermal titration calorimetry (ITC) using ctDNA, [poly(dCdG)](2) and [poly(dAdT)](2), and by a topoisomerase I DNA unwinding (Topo I) assay. The dyes of this study showed tight binding to ctDNA with binding constants, K(b), on the order of 10(6)-10(7)M(-1). The ITC and Topo I assay studies suggested that the 9-substituent has a strong impact on binding modes ranging from an apparent preference for intercalation with a 9-2-thienyl substituent (similar binding to [poly(dCdG)](2) and [poly(dAdT)](2), re-supercoiling of DNA in the Topo I assay at <10(-5)M dye), to mixed binding modes with 9-phenyl derivatives (2- to 3-fold preference for binding to [poly(dAdT)](2), re-supercoiling of DNA in the Topo I assay at approximately 2 x 10(-5)M dye), to minor groove binding in a 9-(2-thienyl-5-diethylcarboxamide) derivative (strong preference for binding to [poly(dAdT)](2), did not show complete re-supercoiling in the Topo I assay).

Visual pigment and oil droplet characteristics of the bobolink (Dolichonyx oryzivorus), a new world migratory bird.

The retinal photoreceptors of a New World migratory bird, the bobolink (Dolichonyx oryzivorus) were examined using microspectrophotometry. Based on the absorbance spectra of their visual pigments and oil droplets, retinal photoreceptors include five classes of single cones, one double cone, and one rod. The single cones contain a long-wavelength pigment (lambda(max)=564nm) paired with a red or clear droplet, a medium-wavelength pigment (lambda(max)=505nm) with an orange or yellow droplet, and an ultraviolet pigment (lambda(max)=372nm) with a transparent droplet.

Detection of charged particles with charge injection devices.

A method for using charge injection devices (CIDs) for detection of high-energy charged particles from inertial-confinement fusion reactions is described. Because of the relatively small depletion region of the CID camera (depletion depth of approximately 7 mum), aluminum foils are placed in front of the device to reduce the energy of the charged particles and maximize the energy deposited in the CID. Simultaneous measurements of (2)H(d,p)(3)H protons with a CID and a surface barrier detector indicate that the CID is an efficient detector of charged fusion products.

Synthesis of analogues of a flexible thiopyrylium photosensitizer for purging blood-borne pathogens and binding mode and affinity studies of their complexes with DNA.

A series of thio- and selenopyrylium analogues of 2,4-di(4-dimethylaminophen-yl)-6-methylthiopyrylium iodide were prepared in five steps from 4-dimethylaminophenyl-propargyl aldehyde and the corresponding lithium acetylide. When bound to DNA, all of the dyes absorb at wavelengths >600nm, which avoids the hemoglobin band I maximum at 575nm. The binding of the series of dyes to double-stranded DNA was examined spectrophotometrically and by isothermal titration calorimetry to determine binding constants, by a topoisomerase I DNA unwinding assay, by competition dialysis with [poly(dGdC)](2) and [poly(dAdT)](2), and by ethidium bromide displacement studies to examine propensities for intercalation, and by circular dichroism studies.

Network structure, and vaccination strategy and effort interact to affect the dynamics of influenza epidemics.

There is growing interest in understanding and controlling the spread of diseases through realistically structured host populations. We investigate how network structures, ranging from circulant, through small-world networks, to random networks, and vaccination strategy and effort interact to influence the proportion of the population infected, the size and timing of the epidemic peak, and the duration of the epidemic. We found these three factors, and their higher-order interactions, significantly influenced epidemic development and extent.

Binding mode and affinity studies of DNA-binding agents using topoisomerase I DNA unwinding assay.

A topoisomerase I DNA unwinding assay has been used to determine the relative DNA-binding affinities of a model pair of homologous naphthalene diimides. Binding affinity data were corroborated using calorimetric (ITC) and spectrophotometric (titration and T(m)) studies, with substituent size playing a significant role in binding. The assay was also used to investigate the mode of binding adopted by several known DNA-binding agents, including SYBR Green and PicoGreen.

Television viewing and long-term weight maintenance: results from the National Weight Control Registry.

Objective: To examine the role of television (TV) viewing in long-term maintenance of weight loss.

Research Methods And Procedures: All subjects (N = 1422) were enrolled in the National Weight Control Registry (NWCR), a national sample of adults who have maintained a minimum weight loss of 13.6 kg for at least 1 year.

Evidence underlying breathing retraining in people with stable chronic obstructive pulmonary disease.

The efficacy of pursed-lip breathing (PLB) and diaphragmatic breathing (DB) in the rehabilitation of people with chronic obstructive pulmonary disease (COPD) remains unclear. This review examines the evidence regarding the usefulness of these techniques in improving the breathing of people with stable COPD. The studies included in our review of the literature used either PLB or DB in isolation, contained a clear description of the methods, and used outcomes that were measured with what we considered to be appropriate procedures.

Consequences of children's exposure to community violence.

Much has been learned over the past decade about the way children respond to experiences of violence in their community. The goal of this paper is to review what is known about the effects of community violence on children's development. In addition to main effects, factors that mediate these effects, as well as factors that moderate children's response to community violence are discussed.

Links between community violence and the family system: evidence from children's feelings of relatedness and perceptions of parent behavior.

In this study, we examined some of the ways in which broader ecological systems may influence the organization of behavior within the family system. Specifically, links between exposure to community violence and children's relationships with maternal caregivers were investigated in a sample of 127 urban children between the ages of 7 and 13 years. Children were asked to indicate whether they had been exposed to a wide variety of violent events.

Attitudes and beliefs about childbirth among college students: results of an educational intervention.

Background: Research on knowledge of childbirth has focused primarily on expectant mothers. The purpose of this study was to investigate college student beliefs, knowledge of, and interest in learning more about childbirth.

Methods: Qualitative research methods were used to analyze college students' written responses to a childbirth video as the first stage in a research project aimed at understanding nulliparous and prepaternity knowledge of childbirth among adolescents and young adults.