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This study investigated flow characteristics around a cylindrical pier under a partially submerged bridge deck. The tests were carried out in clear water conditions for both free-surface and pressure-flow conditions. Three-dimensional velocity measurements were taken at different positions along the centreline of the flume using an acoustic Doppler velocimeter. The results showed that the longitudinal and vertical velocity components of the pressure-flow increased in the vicinity of the pier as compared with those of the free-surface flow. Large values of the turbulence intensities, turbulent kinetic energy and Reynolds shear stress were observed at the upstream edge of the bridge deck within the shear layer and downstream of the pier under the deck due to the generation of wake vortices. Flow contraction and acceleration around the pier's sides resulted in a local increase of the bed shear stress.

Global warming and sea level rise are serious threats to agriculture. The negative effects caused by severe salinity include discoloration and reduced surface of the leaves, as well as wilting due to an impaired uptake of water from the soil by roots. Nanotechnology is emerging as a valuable ally in agriculture: several studies have indeed already proven the role of silicon nanoparticles in ameliorating the conditions of plants subjected to (a) biotic stressors. Here, we introduce the concept of phyto-courier: hydrolyzable nanoparticles of porous silicon, stabilized with the nonreducing saccharide trehalose and containing different combinations of lipids and/or amino acids, were used as vehicle for the delivery of the bioactive compound quercetin to the leaves of salt-stressed hemp (Cannabis sativa L., Santhica 27). Hemp was used as a representative model of an economically important crop with multiple uses. Quercetin is an antioxidant known to scavenge reactive oxygen species in cells. Four different silicon-based formulations were administered via spraying in order to investigate their ability to improve the plant's stress response, thereby acting as nano-biostimulants. We show that two formulations proved to be effective at decreasing stress symptoms by modulating the amount of soluble sugars and the expression of genes that are markers of stress-response in hemp. The study proves the suitability of the phyto-courier technology for agricultural applications aimed at crop protection.

Introduction: The plants have well-developed defense mechanisms against pests and are excellent sources of new insecticidal substances. Materials and methods: An experiment was conducted on Hamedan Agricultural Research Center, as factorial based on completely randomized blocks in 3 replications during 2009. Experimental treatments included 10 levels concentration with Cinnamomum zeylanicum (0, 5, 10, 15, 20, 25, 75, 100, 200, 300) µl, 7 levels concentration with Thymus vulgaris (0, 0.25, 0.50, 0.75, 10, 20, 30) µl, 6 levels concentration with Ferula assafoetida L (0, 30, 60, 90, 120, 150) µl as the time at 3 levels (8, 24, 48) hours as the second factor. 1 ml of solutiones were applied on filter papers with Whatman No. 1. Then each dried paper was placed and 10 C. maculatus adults was placed. Each set of treatment was repeated 3 times and number of dead insects in was counted at an interval of 8, 24, 48 hours respectively. Conclusion: Percentage mortality was calculated. It has been results that the C. zeylanicum, T. vulgaris, F. assafoetida L essential oils showed 13%, 56%, 10% mortality adult of C. maculatus at dose of 5 µl of C. zeylanicum, 0.25 µl of T. vulgaris, 30 µl of F. assafoetida L respectively. Further concentration increase to 300 µl of C. zeylanicum oil, 30 µl of T. vulgaris, 150 µl F. assafoetida L yielded mortality of 100% against adult C. maculatus respectively.

Evidence suggests that the performance of medical students is affected by the quality of teaching of clinical teachers, and the higher teachers' teaching quality leads to better students' clinical performance. Hence, the present research aimed to investigate the association between teaching self-efficacy and quality of bedside teaching among medical teachers.This is a cross-sectional study. To this end, 242 medical teachers and 830 medical students from 6 universities in different cities were selected using convenience sampling. The medical teachers filled out Physician Teaching Self-Efficacy Questionnaire (α=0.93), and medical students completed the quality of bedside teaching questionnaire (BST) (α=0.91). Confirmatory factor analysis (CFA), Pearson correlation coefficient, and multiple regression were used to analyze the collected data through SPSS 23 and Smart-PLS3 software.The results of confirmatory factor analysis (CFA) demonstrated that all items and measurement models had adequate reliability and validity to enter the final analysis (α0.7, CR0.7 AND AVE0.50). Furthermore, the results showed teaching self-efficacy (r=0.27, p0.001) and its components including self-regulation (r=0.24, p0.001), dyadic regulation (r=0.22, p0.001), and triadic regulation (r=0.33, p0.001) had a positive and significant relationship with quality of bedside teaching. Also, the results of multiple regression revealed that among the predictor variables, only the triadic regulation variable could predict the quality of bedside teaching of medical teachers (β=0.326, p0.001).According to the findings, as the medical teachers' teaching self-efficacy improves, they can provide high-quality teaching to students, which in turn will lead to better learning and, therefore better performance for medical students.

Global warming and sea level rise are serious threats to agriculture. The negative effects caused by severe salinity include discoloration and reduced surface of the leaves, as well as wilting due to an impaired uptake of water from the soil by roots. Nanotechnology is emerging as a valuable ally in agriculture: several studies have indeed already proven the role of silicon nanoparticles in ameliorating the conditions of plants subjected to (a) biotic stressors. Here, we introduce the concept of phyto-courier: hydrolyzable nanoparticles of porous silicon, stabilized with the nonreducing saccharide trehalose and containing different combinations of lipids and/or amino acids, were used as vehicle for the delivery of the bioactive compound quercetin to the leaves of salt-stressed hemp (

We reported the photothermal studies on the PEGylated Fe3O4 nanoparticles. In our study, we prepared a series of PEGylated Fe3O4 nanoparticles with different formulations and found that all the PEGylated Fe3O4 nanoparticles have both the photothermal conversion effect and magnetic hyperthermia. We first tried to illustrate the importance of photothermal effect and magnetic heating in the hyperthermia of Fe3O4 nanoparticles, and describe the relationship between the structures and functions. Among these samples, there were two different structures. One is a similar colloidal nanostructure, while the other is a typical nanoparticle structure. Both of them have the similar ultraviolet-visible absorption spectra, Fourier transform infrared spectra and X-ray diffraction patterns. However, the second nanoparticles have higher photothermal conversion efficiency and magnetic resonance imaging contrast than the first colloidal nanostructures. Moreover, by transmission electron microscopy, we found that when the core diameter was in the range of 19–20 nm, the temperature change was above 28 C by photothermal effect, while the magnetic heating was low. All these results not only help us have more comprehensive understanding of Fe3O4 nanoparticle properties, but also provide a rational theoretical support for applying Fe3O4 nanoparticles as a suitable candidate in the photothermal treatment.

BACKGROUND: There is growing acknowledgment that medical education can be a stressful experience for students and may have a devastating effect on their psychological well-being. The present article, therefore, aimed at investigating students' academic resilience as a mediating variable in self-efficacy-test anxiety relation. MATERIALS AND METHODS: In this cross-sectional correlational study, a convenience sample of 243 medical students was selected and participated, three prevalidated questionnaires were applied, that is, general self-efficacy questionnaire, academic resilience questionnaire, and test anxiety questionnaire. To analyze the data, Pearson's correlation coefficient as well as structural equation modeling (SEM) were used. RESULTS: According to Pearson's coefficients, self-efficacy was found to be positively correlated with academic resilience (r = 0.437, P ≤ 0.01) and negatively with test anxiety (r = −0.475, P ≤ 0.01). SEM results also indicated that self-efficacy positively impacts on academic resilience (β = 0.43, P < 0.001) and negatively on test anxiety (β = −0.37, P < 0.001). In addition, results demonstrated the mediating role of academic resilience in self-efficacy-test anxiety relationship (β = −0.108, P < 0.001). CONCLUSION: This study showed that academic resilience could play a mediating role in students' self-efficacy-test anxiety relationship.

Synthetic tripeptide based noncytotoxic hydrogelators have been discovered for releasing an anticancer drug at physiological pH and temparature. Interestingly, gel stiffness, drug release capacity and proteolytic stability of these hydrogels have been successfully modulated by incorporating d-amino acid residues, indicating their potential use for drug delivery in the future.

Lumican derived peptide amphiphiles can stimulate cells to produce greater amounts of collagen when used in an aggregated form. Moreover this effect is maintained following dilution suggesting that the aggregated forms are kinetically trapped when formed at high concentration., C16-YEALRVANEVTLN, a peptide amphiphile (PA) incorporating a biologically active amino acid sequence found in lumican, has been examined for its influence upon collagen synthesis by human corneal fibroblasts in vitro, and the roles of supra-molecular assembly and activin receptor-like kinase ALK receptor signaling in this effect were assessed. Cell viability was monitored using the Alamar blue assay, and collagen synthesis was assessed using Sirius red. The role of ALK signaling was studied by receptor inhibition. Cultured human corneal fibroblasts synthesized significantly greater amounts of collagen in the presence of the PA over both 7-day and 21-day periods. The aggregation of the PA to form nanotapes resulted in a notable enhancement in this activity, with an approximately two-fold increase in collagen production per cell. This increase was reduced by the addition of an ALK inhibitor. The data presented reveal a stimulatory effect upon collagen synthesis by the primary cells of the corneal stroma, and demonstrate a direct influence of supra-molecular assembly of the PA upon the cellular response observed. The effects of PA upon fibroblasts were dependent upon ALK receptor function. These findings elucidate the role of self-assembled nanostructures in the biological activity of peptide amphiphiles, and support the potential use of a self-assembling lumican derived PA as a novel biomaterial, intended to promote collagen deposition for wound repair and tissue engineering purposes.

Insight is provided into the thermodynamics and kinetics of peptide fibrillization, a process of particular interest in biomedicine due to its direct relationship to amyloid diseases. The studied isomeric tetrapeptides are terminally end-capped and present two hydrophobic phenylalanine residues and two ionizable hydrophilic aspartic acid residues. These compounds form gels in water which are composed of self-assembled fibrillar networks. Potentiometric titrations have afforded acid-base and solubility constants associated with the fibrillization process. A remarkable pKa shift of the peptide side chains is observed linked to aggregation, allowing for fiber formation at pH values around neutrality. The magnitude of the pKa shift is directly related to the solubility of the tetrapeptides, namely, to the free energy change associated with fibrillization. Therefore, potentiometric titration emerges as a simple tool to evaluate the thermodynamic parameters of the process. Additionally kinetic measurements with NMR, fluorescence spectroscopy, and SANS reveal that initial peptide dimerization is most likely to be the fibrillization rate-determining step. The aggregation process in all cases presents a relatively long lag time of ca. 1-3 h and takes more than 8 h to complete. No correlation is observed between kinetic and thermodynamic parameters. Finally, kinetically controlled self-sorting of a mixture of two isomeric tetrapeptides is described. © 2015 American Chemical Society. M.T.-S., B.E., and J.F.M. thank the Ministry of Science and Innovation of Spain (Grant CTQ2012-37735) and Universitat Jaume I (Grants P1.1B2012-25 and P1.1B2013-57) for financial support. M.T.-S. thanks the Ministry of Science and Innovation of Spain for a Ph.D. fellowship (FPU program). We are grateful to ISIS for the award of beamtime on SANS2D (Reference RB 122066), and we thank Richard Heenan for assistance on the beamline.

We describe a bioactive lipopeptide that combines the capacity to promote the adhesion and subsequent self-detachment of live cells, using template-cell-environment feedback interactions. This self-assembling peptide amphiphile comprises a diene-containing hexadecyl lipid chain (C16e) linked to a matrix metalloprotease-cleavable sequence, Thr-Pro-Gly-Pro-Gln-Gly-Ile-Ala-Gly-Gln, and contiguous with a cell-attachment and signalling motif, Arg-Gly-Asp-Ser. Biophysical characterisation revealed that the PA self-assembles into 3 nm diameter spherical micelles above a critical aggregation concentration (cac). In addition, when used in solution at 5–150 nM (well below the cac), the PA is capable of forming film coatings that provide a stable surface for human corneal fibroblasts to attach and grow. Furthermore, these coatings were demonstrated to be sensitive to metalloproteases expressed endogenously by the attached cells, and consequently to elicit the controlled detachment of cells without compromising their viability. As such, this material constitutes a novel class of multi-functional coating for both fundamental and clinical applications in tissue engineering.

In the present study, a combination of cold rolling and subsequent annealing was used to produce an AISI 304L stainless steel with different grain sizes (650 nm, 3 μm and 12 μm). Wear behavior of the steel was subsequently examined using dry sliding wear test under different loads of 10 N, 20 N and 30 N. Different microstructural characterizations were conducted on the samples. The results demonstrated that the ultra-fine grained steel (650 nm grain size) had better wear resistance under normal loads of 10 N and 20 N, whereas under the normal load of 30 N, it showed weak wear resistance as compared to the steel with larger grain size (3 μm and 12 μm). This behavior can be attributed to the amount of induced martensitic transformation formed during the wear test. This transformation was evaluated using XRD analysis and quantified by Ferritescope measurements. Wear mechanism was recognized as delamination in the early stages of the wear test and the mixture of delamination and abrasion for higher distances.

A new synthetic tripeptide-based hydrogel has been discovered at physiological pH and temperature. This hydrogel has been thoroughly characterized using different techniques including field emission scanning electron microscopic (FE-SEM) and high-resolution transmission electron microscopic (HR-TEM) imaging, small- and wide-angle X-ray diffraction analyses, FT-IR, circular dichroism, and rheometric analyses. Moreover, this gel exhibits thixotropy and injectability. This hydrogel has been used for entrapment and sustained release of an antibiotic vancomycin and vitamin B12 at physiological pH and temperature for about 2 days. Interestingly, MTT assay of these gelator molecules shows almost 100% cell viability of this peptide gelator, indicating its noncytotoxicity.

An ultrafine grained 304L stainless steel with average grain size of 650±100 nm was produced by a combination of cold rolling and annealing. Wear behavior of the steel was examined by dry sliding wear tests under different loads. Different microstructural characterizations were conducted on the ultrafine grained structure after thermomechanical processing and wear tests. The results demonstrated that the steel had yield strength of 720 MPa and total elongation of 47%, which is almost twice higher than typical coarse grained strength. Also, wear tests results showed a good linear relation between the cumulative wear loss and distance in each normal load. Wear rate was about 0.024, 0.043 and 0.093 mg/m for normal loads of 10, 20 and 30N, respectively. Wear mechanism was also recognized as delamination (in the early stage) and mixture of delamination and abrasion in higher distances.

Supporting Information Peptide based Ambidextrous Bifunctional Gelator: Applications in Oil Spill Recovery and Removal of Toxic Organic Dyes for Waste Water Management

Organizations, as social units, comprise conflicting and contrary components which expel each other. What prevents the organization from falling apart and lubricates organizational actions is Organizational Social Capital (OSC). Therefore, how OSC is generated and maintained must be considered and studied. Hence, we attempt to study the role that Human Resource Management (HRM) plays to generate OSC. In order to generate OSC some individual qualities are necessary and HRM practices, like selection, socialization, training and rewarding, can improve and enhance the individual qualities and, as a result, facilitate OSC creation and maintenance. This study examines the specific role of human resource management in creating OSC.

In this study, an aluminium–zinc composite was produced for the first time by using a continual annealing and roll-bonding (CAR) process. A composite with homogeneous distribution of fragmented zinc layers in aluminium matrix was produced after ten CAR cycles. The results demonstrate that tensile strength of the final composites increases up to 410 MPa, which is about 4 times higher than those of initial aluminium and zinc sheets. However, elongation of the composite reduced down to 4% after ten CAR cycles. The fracture surfaces of the tensile samples were observed by scanning electron microscope (SEM) to evaluate the failure mode. Observations reveal that the failure mode in CAR-processed composites is a typical ductile fracture which shows deep dimples in samples with few CAR cycles, while the failure mode was shear ductile fracture with shallow and elongated dimples in samples with ten CAR cycles.

In this study, Al–Zn composite was produced for the first time by using of Al 1050 and commercial Zn alloy sheets through accumulative roll bonding (ARB) process at ambient temperature. In this process after sandwich preparation, in per cycle applied 50% reduction in thickness. It was observed that by increasing ARB cycles, thickness of individual Al and Zn sheets decreased; finally, zinc layers were necked, fractured and dispersed in the aluminum matrix. After ten ARB passes, an Al–Zn composite with homogeneously distribution of fragmented zinc layers with thickness of less than 3 μm in aluminum matrix was produced. Structure and mechanical properties of this composite were evaluated at different cycles of ARB process. During ARB cycles, it was observed that with increase of number of ARB cycles, the strength and microhardness increased while elongation at the first cycles increased and then decreased.

On the basis of laboratory experiments, this paper investigates the effect of different bed forms and vegetated banks on flow velocity, Reynolds stresses, and turbulence intensities. Experimental measurements were made over fifth and sixth dunes in a series of seven of two-dimensional (2D) asymmetric gravel dunes that had lee-slope angles of 28° and 35°, respectively. These dunes had a mean wavelength of 0.96 m, mean dune height of 0.08 m, and width equal to the flume width. Rice stems with a median diameter of 2.7 mm and a stem distribution density of 400 stems/m were used to cover the flume banks for simulating vegetation on river banks. From experimental measurements, the effect of the distance from the vegetated bank on the velocity field, turbulent intensities, and Reynolds stress distribution; the effect of different angles of lee slope of gravel dunes on the characteristics of a flow-in vegetated flume; and the reattachment points for different angles of lee slope of gravel dunes were investigated.

Vegetation on river banks and bed roughness are important factors affecting flow structure, sediment transport, erosion and geomorphology in rivers. In this experimental study, the impacts of vegetation on flume walls, grain size of bed gravels and aspect ratio on characteristics of shear stress distribution, Coles' wake parameter, the kinematic energy correction factor (α) and the momentum correction factor (β) have been assessed. Reynolds stress distribution illustrates a three-layer pattern when the aspect ratio is smaller than 2. In addition, the aspect ratio and changes of vegetation affect α, β as well as the Coles' wake parameter Π.

The self-assembly in aqueous solution of three lipopeptides obtained from Bacillus subtilis has been investigated. The lipopeptides surfactin, plipastatin and mycosubtilin contain distinct cyclic peptide headgroups as well as differences in alkyl chain length, branching and chain length distribution. Cryogenic transmission electron microscopy and X-ray scattering reveal that surfactin and plipastatin aggregate into 2 nm-radius spherical micelles, whereas in complete contrast mycosubtilin self-assembles into extended nanotapes based on bilayer ordering of the lipopeptides. Circular dichroism and FTIR spectroscopy indicate the presence of turn structures in the cyclic peptide headgroup. The unexpected distinct mode of self-assembly of mycosubtilin compared to the other two lipopeptides is ascribed to differences in the surfactant packing parameter. This in turn is due to specific features of the conformation of the peptide headgroup and alkyl chain branching.

A dipeptide with a long fatty acid chain at its N-terminus gives hydrogels in phosphate buffer in the pH range 7.0–8.5. The hydrogel with a gelator concentration of 0.45% (w/v) at pH 7.46 (physiological pH) provides a very good platform to study dynamic changes within a supramolecular framework as it exhibits remarkable change in its appearance with time. Interestingly, the first formed transparent hydrogel gradually transforms into a turbid gel within 2 days. These two forms of the hydrogel have been thoroughly investigated by using small angle X-ray scattering (SAXS), powder X-ray diffraction (PXRD), field emission scanning electron microscopic (FE-SEM) and high-resolution transmission electron microscopic (HR-TEM) imaging, FT-IR and rheometric analyses. The SAXS and low angle PXRD studies substantiate different packing arrangements for the gelator molecules for these two different gel states (the freshly prepared and the aged hydrogel). Moreover, rheological studies of these two gels reveal that the aged gel is stiffer than the freshly prepared gel.

Colorectal cancer (CRC) is the second most prevalent cancer worldwide, and in 35% of cases it is an inherited form. The most common inherited forms of CRC include; Lynch syndrome, familial adenomatous polyposis (FAP), attenuated FAP, and MUTYH-associated polyposis (MAP). Although they are inherited, they have different phenotypic effects with regards to the number of polyposis, age of onset and the pattern of inheritance. Some of these CRCs are associated with other extracolonic manifestation symptoms. MUTYH-associated polyposis (MAP) was first described in 2002. MUTYH is a component of a base excision repair system that protects the genomic information from oxidative damage. When the MUTYH gene product is impaired by bi-allelic germline mutation, it leads to the mutation of cancer-related genes, such as the APC and/or the KRAS genes, via G to T transversion. MAP is a hereditary colorectal cancer syndrome inherited in an autosomal-recessive fashion. The proposed mechanism of individual CRC is distinguished in this review paper.

The peptide amphiphile C16-KTTKS templates silica polymerization, enabling the production of silica nanotape structures, imaged via electron microscopy (TEM and SEM). X-ray scattering shows that the nanotapes comprise stacked layers, as for the parent peptide amphiphile, but with a substantially increased layer spacing resulting from silica polymerization.

The self-assembly of several classes of amphiphilic peptides is reviewed, and selected applications are discussed. We discuss recent work on the self-assembly of lipopeptides, surfactant-like peptides and amyloid peptides derived from the amyloid-β peptide. The influence of environmental variables such as pH and temperature on aggregate nanostructure is discussed. Enzyme-induced remodelling due to peptide cleavage and nanostructure control through photocleavage or photo-cross-linking are also considered. Lastly, selected applications of amphiphilic peptides in biomedicine and materials science are outlined. © 2014 The Authors. Journal of Peptide Science published by European Peptide Society and John Wiley & Sons, Ltd.

The self-assembly in water of designed peptide amphiphile (PA) C16-ETTES containing two anionic residues and its mixtures with C16-KTTKS containing two cationic residues has been investigated. Multiple spectroscopy, microscopy, and scattering techniques are used to examine ordering extending from the β-sheet structures up to the fibrillar aggregate structure. The peptide amphiphiles both comprise a hexadecyl alkyl chain and a charged pentapeptide headgroup containing two charged residues. For C16-ETTES, the critical aggregation concentration was determined by fluorescence experiments. FTIR and CD spectroscopy were used to examine β-sheet formation. TEM revealed highly extended tape nanostructures with some striped regions corresponding to bilayer structures viewed edge-on. Small-angle X-ray scattering showed a main 5.3 nm bilayer spacing along with a 3 nm spacing. These spacings are assigned respectively to predominant hydrated bilayers and a fraction of dehydrated bilayers. Signs of cooperative self-assembly are observed in the mixtures, including reduced bundling of peptide amphiphile aggregates (extended tape structures) and enhanced β-sheet formation.

Studying peptide amphiphiles (PAs), we investigate\ud the influence of alkyl chain length on the aggregation behavior of the collagen-derived peptide KTTKS with applications ranging from antiwrinkle cosmetic creams to potential uses in regenerative medicine. We have studied synthetic peptides amphiphiles C14− KTTKS (myristoyl Lys-Thr-Thr-Lys-Ser) and C18−KTTKS(stearoyl-Lys-Thr Thr-Lys-Ser) to investigate in detail their physicochemical properties. It is presumed that the hydrophobic chain in these self-assembling peptide amphiphiles enhances peptide permeation across the skin compared to KTTKS alone.\ud Subsequently Cn−KTTKS should act as a prodrug and release the peptide by enzymatic cleavage. Our results should be useful in the further development of molecules with collagen-stimulating activity.

A thermal transition is observed in the peptide amphiphile C16-KTTKS (TFA salt) from nanotapes at 20 °C to micelles at higher temperature (the transition temperature depending on concentration). The formation of extended nanotapes by the acetate salt of this peptide amphiphile, which incorporates a pentapeptide from type I procollagen, has been studied previously [V. Castelletto et al., Chem. Commun., 2010, 46, 9185]. Here, proton NMR and SAXS provide evidence for the TFA salt spherical micelles at high temperature. The phase behavior, with a Krafft temperature separating insoluble aggregates (extended nanotapes) at low temperature from the high temperature micellar phase resembles that for conventional surfactants, however this has not previously been reported for peptide amphiphiles.

The surfactant-like peptide (Ala)(6)(Arg) is found to self-assemble into 3 nm-thick sheets in aqueous solution. Scanning transmission electron microscopy measurements of mass per unit area indicate a layer structure based on antiparallel dimers. At higher concentration the sheets wrap into unprecedented ultrathin helical ribbon and nanotube architectures.

A designed peptide amphiphile C16-KKFFVLK self-assembles into nanotubes and helical ribbons in aqueous solution at room temperature. A remarkable unwinding transition, leading to twisted tapes, is observed on heating. Nanotubes and ribbons re-form on cooling.

Here we explore the physico-chemical properties of a peptide\ud amphiphile obtained by chemical conjugation of the collagenstimulating\ud peptide KTTKS with 10,12-pentacosadiynoic acid\ud which photopolymerizes as a stable and extended polydiacetylene.\ud We investigate the self-assembly of this new polymer and rationalize\ud its peculiar behavior in terms of a thermal conformational\ud transition. Surprisingly, this polymer shows a thermal transition\ud associated with a non-cooperative increase in b-sheet content at\ud high temperature.

A particulate microemulsion is generated in a simple two-component system comprising an amphiphilic copolymer (Pluronic P123) in mixtures with tannic acid. This is correlated to complexation between the poly(ethylene oxide) in the Pluronic copolymer and the multiple hydrogen bonding units in tannic acid which leads to the breakup of the ordered structure formed in gels of Pluronic copolymers, and the formation of dispersed nanospheres containing a bicontinuous internal structure. These novel nanoparticles termed “emulsomes” are self-stabilized by a coating layer of Pluronic copolymer. The microemulsion exhibits a pearlescent appearance due to selective light scattering from the emulsion droplets. This simple formulation based on a commercial copolymer and a biofunctional and biodegradable additive is expected to find applications in the fast moving consumer goods sector.

Amyloid fibrils are formed by a model surfactant-like peptide (Ala)10-(His)6 containing a hexa-histidine tag. This peptide undergoes a remarkable two-step self-assembly process with two distinct critical aggregation concentrations (cac’s), probed by fluorescence techniques. A micromolar range cac is ascribed to the formation of prefibrillar structures, whereas a millimolar range cac is associated with the formation of well-defined but more compact fibrils. We examine the labeling of these model tagged amyloid fibrils using Ni-NTA functionalized gold nanoparticles (Nanogold). Successful labeling is demonstrated via electron microscopy imaging. The specificity of tagging does not disrupt the β-sheet structure of the peptide fibrils. Binding of fibrils and Nanogold is found to influence the circular dichroism associated with the gold nanoparticle plasmon absorption band. These results highlight a new approach to the fabrication of functionalized amyloid fibrils and the creation of peptide/nanoparticle hybrid materials., Biomacromolecules, 15 (9), ISSN:1525-7797, ISSN:1526-4602

Objective: Somatic symptoms are one of the most prevalent complaints in both psychiatric and general population, and validated scales are required to assess these problems. The present study was conducted to determine psychometric properties of the Persian version of Screening for Somatic Symptom Disorders-7(SOMS-7) in an Iranian population. Method: This was a multi centric comprehensive study conducted in Psychosomatic Research Center of Isfahan University of Medical Sciences in collaboration with Department of Clinical Psychology of Philipp University of Marburg, Germany. This part of the study includes 100 patients with anxiety/mood disorders and 291 healthy individuals. All participants completed the Patient Health Questionnaire (PHQ-15) and Screening for Somatic symptom disorders 7(SOMS-7). Data were analyzed by Pearson and Spearman correlation coefficient, factor analysis, independent t test, and discriminant analysis using SPSS-20 software. Results: Reliability coefficient based on Cronbach’s alpha was 0.92 and 0.94 (clinical vs. healthy sample). Validity index of the SOMS according to correlation between factor 1 and 2 with PHQ somatic subscale was. 51 and. 59, respectively. Score of 15.5 as cut-off point was accompanied with sensitivity of 77% and specificity of 66%. Factor analysis extracted 2 factors in patients and 4 factors in healthy population. Conclusion: Findings of this study indicated that the Persian version of SOMS-7 has appropriate reliability and validity for the assessment of somatic symptoms disorder and evaluation of treatment effects in these patients.