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Stereoselective total synthesis of several analogues of piscibactin (Pcb), the siderophore produced by different pathogenic Gram-negative bacteria, was performed. The acid-sensitive α-methylthiazoline moiety was replaced by a more stable thiazole ring, differing in the configuration of the OH group at the C-13 position. The ability of these Pcb analogues to form complexes with Ga3+as a mimic of Fe3+showed that the configuration of the hydroxyl group at C-13 as 13Sis crucial for the chelation of Ga3+to preserve the metal coordination, while the presence of a thiazole ring instead of the α-methylthiazoline moiety does not affect such coordination. A complete 1H and 13C NMR chemical shift assignment of the diastereoisomer mixtures around C9/C10 was done for diagnostic stereochemical disposition. Additionally, density functional theory calculations were performed not only for confirming the stereochemistry of the Ga3+complex among the six possible diastereoisomers but also for deducing the ability of these to form octahedral coordination spheres with gallium. Finally, the lack of antimicrobial activity of Pcb and Pcb thiazole analogue Ga3+complexes against Vibrio anguillarumagrees with one of the roles of siderophores in protecting pathogens from metal ion toxicity. The efficient metal coordination shown by this scaffold suggests its possible use as a starting point for the design of new chelating agents or vectors for the development of new antibacterials that exploit the “Trojan horse” strategy using the microbial iron uptake mechanisms. The results obtained will be of great help in the development of biotechnological applications for these types of compounds.

The new Ultimate EAF from Siemens is the latest development in the field of electric arc steelmaking furnaces. Features of the electric arc furnace are presented.

The leaves of Passiflora ligularisJuss (known as sweet granadilla for its edible fruits) are a crop byproduct that is discarded. With the aim of contributing to give value-added products from these crop by-side products to farmers of Colombian Andes, we carried out a 1H-NMR-metabolomics analysis of polar extracts from leaves collected in three locations and stored in two conditions in order to identify glucosyl-hydrolase inhibitors. Variations in the metabolic profile and the bioactivity among samples were analyzed by orthogonal partial least square discriminant analysis. Thus, 1H-NMR signals related to polyphenolic compounds, saponins, and amino acids were correlated with higher inhibitory activities. Moreover, a targeted NMR and HPLC–MS/MS analysis allowed the identification of 14 polyphenolic compounds and the structural characterization of a new triterpenoid saponin, ligularoside A. The measurements of IC50values for α-amylase and α-glycosidase inhibitors allowed the identification of quercetin-3-O-β-glucoside, kaempferol-3-O-β-glucoside, and ligularoside A as the most active compounds. These results suggest that P. ligularisleaves are a source of glucosyl-hydrolase inhibitors and lay the foundation for exploring additional applications.

Hispanic American authors are enjoying increased mainstream acceptance. Large editorial houses have begun publishing the works of Sandra Cisneros, Gary Soto and Denise Chavez while small and underground publishers are flourishing from the growing interest in multicultural writings.

Aqueous extract of Opuntia ficus-indica(OF) was employed to reduce salt solutions of silver nitrate, gold chloride and silver nitrate/gold chloride to OFAgNPs, OFAuNPs, and OFAg-AuNPs respectively. Characterization of the particles was carried out using different standard methods, and their antimicrobial and antioxidant activities were also evaluated. The UV-vis spectroscopy showed silver, gold and silver-gold alloys nanoparticles with surface plasmon resonance at 462, 545 and 539 nm, respectively. The significant FTIR peaks: OFAgNPs (3300 and 1635 cm−1), OFAuNPs (3288 and 1635 cm−1) and OFAg-AuNPs (3307 and 1637 cm−1) for synthesized nanoparticles pointed to protein as both capping and stabilizing agent. Generally, particles were spherical with size range of 27-38 nm, 11-28 nm and 15-54 nm for silver, gold and silver-gold alloys nanoparticles respectively. OFAgNPs gave highest antagonistic effects against tested bacteria (35-82%), followed by OFAg-AuNPs (12-75%) and AuNPs (11-48%). The fungal inhibition of 44-70% for OFAgNPs, 42-79% for OFAuNPs and 52-92% for OFAg-AuNPs were obtained. DPPH scavenging activities were obtained as follows: OFAgNPs (52.25–57.50%), OFAuNPs (37.07-59.07%) and OFAg-AuNPs (37.07-63.00%) at tested concentrations of 20–100 µg/ml, which were dose-dependent in comparison with standard BHA (42.57–91.27%) and ascorbic acid (52.13–84.20%). The bleaching inhibition assay of ABTS showed activities of 41.33–61.83% (OFAgNPs), 27.37-50.60% (OFAuNPs) and 32.83-44.33% (OFAg-AuNPs). The synthesized nanoparticles demonstrated an excellent antioxidant and antimicrobial activity. The current study, to the best of our knowledge, is the first time to use Opuntia ficus-indicato synthesize silver, gold and silver-gold alloys nanoparticles.

Lanthanide complexes Ln(L1)(HL1) (Ln = Lu, Yb, Er, Gd, Eu, Sm) and Ln(L2)(HL2) (Ln = Lu, Yb, Gd, Eu) with 2-(tosylamino)-benzylidene-N-(aryloyl)hydrazones (H2L1, aryloyl = 2-hydroxybenzoyl; H2L2, aryloyl = isonicotinoyl) were obtained with the aim to explore them as new luminescent materials. They were found to form monomeric species independently on the aryloyl group, and their crystal structures were determined from single-crystal X-ray data (Yb(L2)(HL2)·0.5(C2H5OH)), as well as from powder X-ray data by Rietveld refinement (Eu(L1)(HL1)). Ytterbium complexes exhibited intense luminescence, which allowed using them in host-free organic light-emitting diodes, which demonstrated remarkable efficiency of near infrared electroluminescence (50 μW/W) at low voltage (5 V). The special mechanism of europium luminescence quenching allowed using europium complexes as luminescent thermometers, which demonstrated very high sensitivity up to 12%/K. The theory of luminescence thermometry based on a three-level system was proposed, which allowed predicting sensitivity with high accuracy (error within 20%).

An analysis has been carried out to study the effects of variable fluid viscosity and variable thermal conductivity on mixed convection heat transfer due to an exponentially stretching surface with external magnetic field. The basic boundary layer equations governing the flow and heat transfer are in the form of partial differential equations. These PDE’s are converted into non-linear ordinary differential equations using the suitable similarity transformations. The resulting boundary value problems of flow and heat transfer are solved by using the Runge–Kutta Fehlberg method with efficient shooting technique. The effect of variable viscosity, variable thermal conductivity, Prandtl number, magnetic field parameter, Eckert number, and Grashof’s number (buoyancy) on velocity and temperature are plotted (for PST and PHF case) and discussed in detail.

The main goal of this study was the preparation of materials containing phosphoric functionalities on the base of industrial polymer - divinyl rubber and the assessment of their removal efficiency of heavy metals from aqueous solutions. The new method concerns the oxidative chlo-rophosphorylation of divinyl rubber by PCl3with the following modification of obtained inter-mediates to create -PO(OH)2, -OPO(OH)2groups in the polymer chain. The obtained modified polymers get some new properties such as complex formation and capability for ion exchange. The nature and distribution of phosphoric functionalities in the polymer were studied by the methods of NMRand FTIR- spectroscopy, thermal analysis and scanning electron microscopy. The sorption properties of synthesized polymers towards some cations (Cu+2, Ni+2, Co+2and Zn+2) from water solutions have been tested. It has been shown that the metal removal efficiency of prepared material depends on pH of medium, initial concentration and type of metal ions.

The electronic and magnetic properties of Mn coordinated to 1,2,4,5-tetracyanobenzene (TCNB) in Mn–TCNB two-dimensional metal–ligand networks have been investigated by combining scanning tunneling microscopy and X-ray magnetic circular dichroism (XMCD) performed at low temperature (3 K). When formed on Au(111) and Ag(111) substrates, the Mn–TCNB networks display similar geometric structures. Magnetization curves reveal ferromagnetic coupling of the Mn sites with similar single-ion anisotropy energies but different coupling constants. Low-temperature XMCD spectra show that the local environment of the Mn centers differs appreciably for the two substrates. Multiplet structure calculations were used to derive the corresponding ligand field parameters, confirming an in-plane uniaxial anisotropy. The observed interatomic coupling is discussed in terms of superexchange as well as substrate-mediated magnetic interactions.

Objective:To investigate the antimicrobial activity of SAP-containing wound dressings in vitroover a prolonged period of time (7 days) and to assess their ability to sustain the antimicrobial effect.Method:SAP dressings were tested according to the JIS L 1902:2002 against the pathogens Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coliand Candida albicans. Additionally, effect on S. aureusand P. aeruginosagrowth was investigated after a prolonged incubation period of 7 days. Furthermore, both SAP dressings were repeatedly inoculated with P. aeruginosasuspension and, after 7 days, microbial growth under the dressings was evaluated.Results:Both SAP-containing wound dressings tested exhibited a significant to strong antimicrobial activity against Staphylococcus aureus, MRSA, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Candida albicans in vitro. Moreover, it could be shown that they were able to sustain antibacterial efficacy over a prolonged period of time. Using a direct incubation method with repeated re-inoculation of the dressing samples, it could be shown that growth of P. aeruginosawas reduced after 4 days of treatment and completely inhibited after 7 days. No significant differences were observed between the two SAP-dressings tested.Conclusion:These in vitroexperiments impressively demonstrated the antimicrobial mechanism of SAP-containing wound dressings: rapid up-take of fluid, binding of microorganisms to the SAP-core, and retention of the bacteria inside the dressing. Moreover, it could be shown that they are able to exhibit their antimicrobial activity over a prolonged period of time unless the amount of fluid present exceeds their fluid-handling capacity.Declaration of interest:This work was supported by Lohmann & Rauscher GmbH & Co KG. Authors M. Abel and P. Ruth are employees of Lohmann & Rauscher; J. Muldoon is an employee of Activa Healthcare UK, a company of Lohmann & Rauscher. C. Wiegand received travel grants from Lohmann & Rauscher, to participate at wound healing conferences.

Objective:To compare the clinical efficacy of a collagen dressing covered with a foam dressing with the same foam used as a primary dressing in stagnating granulating pressure ulcer patients.Method:Patients were randomised to receive either a foam dressing (Suprasorb P; Lohmann & Rauscher) as a primary dressing (group A), or a combination of a collagen dressing (Suprasorb C; Lohmann & Rauscher) covered with the same foam dressing (group B). Wound fluid was collected and evaluated prior to treatment (day 0), and on days 3, 7, 14 and 21. The level and expression of matrix metalloproteinases (MMPs) MMP-2 and MMP-9, and tissue inhibitors of metalloproteinases (TIMPs) TIMP-1 and TIMP-2, as well as elastase content in wound fluid and angiogenesis, were evaluated, comparing results on day 0 and day 21. Time to ulcer healing, reduction in ulcer area, safety of treatment, patient-reported ulcer pain and comfort of the dressing regimen were evaluated as secondary outcomes. Patients received standard preventive measures, in line with the pressure ulcer prevention guidelines.Results:Ten patients were included in the pilot; five were treated with the foam dressing (group A) and five patients received the collagen dressing, using the foam as a secondary dressing (group B). Wound fluid from group B displayed a significant positive effect on angiogenesis (p < 0.05) compared with group A. In the collagen and foam group TIMP-1 and -2 increased faster and levels were higher than in group A. Furthermore, MMP-2, MMP-9 (p < 0.04) and elastase in group B showed faster and greater decrease in levels, compared with group A, indicating a faster and superior reduction of inflammation. In both groups the ulcers started to heal, with a faster onset of healing for group B.Conclusion:The results of this pilot support published data on the use of collagen dressings compared with foam for stagnating wounds, shown in clinical studies.Declaration of interest:This study was supported with an educational grant by Lohmann & Rauscher GmbH. Apart from Dr Abel, the sponsors had no role in the design or conduct of the study, in the collection, analysis and interpretation of the data, or in the preparation, review or approval of the manuscript. Dr Abel gave input to the study design from a scientific perspective. None of the authors received administrative, technical or material support for the conduct of this study. The authors have no other relevant financial interests to declare.

Objective:To compare interface pressure (IP) and static stiffness index (SSI) of four different compression systems currently in use for the treatment of patients with venous leg ulcer.Method:Fifty-two ambulatory adults with healthy legs were recruited at random at a study centre after they had consented. The evaluated systems were: short-stretch system (SSB), Rosidal sys (Lohmann & Rauscher), multilayer bandaging (LSB) Profore (Smith & Nephew), Vari-stretch (VSB) ProGuide (Smith & Nephew) and tubular compression (CS) Rosidal Mobil (Lohmann & Rauscher). Interface pressure was measured using Kikuhime (Harada Corp.), placing a 3cm-diameter probe at the B1 point. IP recording took place in the supine and standing positions, while sitting and during walking, on application of the compression systems and every 15 minutes thereafter for 4 hours.Results:The IPs of SSB, LSB and VSB, measured immediately after bandage application, were significantly higher than that of CS (all p < 0.05). During the 4-hour study period, the IP for both VSB and LSB measured in the supine position initially increased to > 60mmHg. Their overall mean IPs in the supine position were 48.96 ± 3.99mmHg and 48.12 ± 4.57mmHg, respectively. SSB and CS demonstrated more tolerable IP levels in this position of < 40mmHg, which was similar to those when sitting. All systems maintained at least 40mmHg in walking. SSB had a high SSI of 20 throughout the study. LSB followed with an SSI of 18 at the start, which reduced to 13, while the SSI for VSB decreased from 17 to 12 and CS, with an SSI of 6, lagged behind.Conclusion:These results may contribute to the understanding of IP and SSI of the four different compression systems evaluated. The IP and SSI data presented give clinicians an indication of the appropriate frequency of re-application of compression, and preliminary data on choosing a safe and effective compression treatment for their patients.Declaration of interest:The investigators received an educational grant from Lohmann & Rauscher GmbH & Co KG for this study.

Objective:This study compares treatment with a polihexanide-containing biocellulose wound dressing (BWD+PHMB) versus the best local standard of silver dressings (Ag) in painful, critically colonised (wounds-at-risk) or locally-infected wounds.Method:Patients with wounds of various aetiologies, a baseline VAS pain score ≥4 and a semi-quantitative bacterial load of ++ or higher were randomly allocated to receive treatment with either BWD+PHMB or Ag. Patients with systemic infections and/or using systemic antibiotics were excluded. The primary endpoint, patient-reported pain (VAS total pain, including the sub-scores pain at night, during the day, before, and 15min after dressing changes), was compared between treatment groups and scored on days 0, 1, 3, 7, 14, 21 and 28. Secondary outcomes of bacterial load, wound bed and periwound skin condition, quality of life and dressing handling were assessed at the same visits.Results:Thirty-eight patients (BWD+PHMB, n=21 [24 wounds]; Ag, n=17 [18 wounds]) were included in the analyses. Baseline variables showed no significant differences. Wound pain was reduced significantly in both groups, with a better pain reduction noted for BWD+ PHMB (p < 0.001) before dressing changes. Compared with Ag, in the BWD+PHMB group critical colonisation and local wound infection had been reduced significantly faster and better (p < 0.001) over the 28-day study period. Improved quality of life, good tolerability and no adverse events were demonstrated for both groups.Conclusion:Both BWD+PHMB and AG were effective in reducing pain and bacterial burden. However, that BWD+PHMB was significantly faster and better in removing the critical bacterial load, makes this dressing an attractive therapeutic option to treat critically colonised and locally-infected wounds.Declaration of interest:This was sponsored by a clinical research grant from Lohmann & Rauscher GmbH & Co. KG. G. Haemmerle, M. Signer, U. Gruber-Moesenbacher and M. Mittlboeck have no conflict of interest to report. T. Eberlein, J. Traber and R. Strohal serve in the speakers bureau of Lohmann & Rauscher GmbH & Co KG. In addition, T. Eberlein and R. Strohal also work as consultants for Lohmann & Rauscher GmbH & Co KG. M. Abel is an employee of Lohmann & Rauscher GmbH & Co KG.

Objective:To evaluate the wound debridement efficacy (that is, achievement of 100% granulation tissue on the wound bed) of a new monofilament fibre product (Debrisoft).Method:This multicentre, prospective, observational evaluation assessed the debridement efficacy, safety, patient comfort and user satisfaction of this new product. Time taken to perform the debridement procedure was also recorded. The new product was wetted with either saline or polihexanide and applied for 2–4 minutes, following which the usual dressing regimen was applied. Clinical outcome was scored by a trained clinician. Additionally, before and after photographs were assessed by one and the same clinician, who was blinded to the treatment given. The debridement outcomes achieved with the test product were compared with results obtained using other methods of debridement, both non-surgical and surgical, taken from an electronic database but using the same scoring systems as here.Results:Sixty patients with chronic wounds requiring debridement were recruited, of whom 57 were included in the analysis. Debridement was effective in 93.4% (142/152) of the sessions, and the product remained intact in 95.4% (145/152). The average time for each debridement session was 2.51 minutes, markedly less than for the current debridement methods at the evaluation centres. visible debris and slough were successfully removed with the test product. Patients reported no pain during the procedure in 45% of cases and slight discomfort for a short duration (2.0 minutes on average) in 55% of cases.Conclusion:The results indicate the potential for this monofilament fibre product to replace several modes of debridement, based on its efficacy, short procedure, ease of use and patient comfort.Conflict of interest:The evaluation protocol was proposed and supported by Lohmann & Rauscher GmbH, who provided the evaluation products. MS and MA are employees of Lohmann & Rauscher. The other authors declare to have no relevant financial interest in the evaluation. apart from input to the protocol, the sponsors had no role in the conduct of the study, such as data collection, analysis, or preparation, review, or approval of the manuscript.

Abstract: In this present article an analysis is carried out to study the boundary layer flow behavior and heat transfer characteristics in Walter’s liquid B fluid flow. The stretching sheet is assumed to be impermeable, the effects of viscous dissipation, non-uniform heat source/sink in the presence and in the absence of elastic deformation (which was escaped from attention of researchers while formulating the viscoelastic boundary layer flow problems)on heat transfer are addressed. The basic boundary layer equations for momentum and heat transfer, which are non-linear partial differential equations, are converted into non-linear ordinary differential equations by means of similarity transformation. Analytical solutions are obtained for the resulting boundary value problems. The effects of viscous dissipation, Prandtl number, Eckert number and non-uniform heat source/sink on heat transfer (in the presence and in the absence of elastic deformation) are shown in several plots and discussed. Analytical expressions for the wall frictional drag coefficient, non-dimensional wall temperature gradient and non-dimensional wall temperature are obtained and are tabulated for various values of the governing parameters. The present study reveals that, the presence of work done by deformation in the energy equation yields an augment in the fluid’s temperature. [Copyright &y& Elsevier]

Abstract: This paper presents the study of momentum and heat transfer characteristics in a hydromagnetic flow of viscoelastic liquid over a stretching sheet with non-uniform heat source, where the flow is generated due to a linear stretching of the sheet and influenced by uniform magnetic field applied vertically. Here an analysis has been carried out to study the effect of magnetic field on the visco-elastic liquid flow and heat transfer over a stretching sheet with non-uniform heat source. The non-linear boundary layer equation for momentum is converted into ordinary differential equation by means of similarity transformation and is solved exactly. Heat transfer differential equation is also solved analytically. The effect of magnetic field on velocity, skin friction and temperature profiles are presented graphically and discussed. [Copyright &y& Elsevier]

Objective:To compare the effect on the microcirculation in venous leg ulcers (VLUs) of two treatment regimens that promote a moist wound environment versus paraffin gauze. The hypothesis is that moist wound dressings are more likely to stimulate the microcirculation and therefore angiogenesis.Method:Patients with non-healing VLUs were randomised to receive either a foam dressing (Suprasorb P), a collagen dressing (Suprasorb C) plus the foam dressing, or paraffin gauze (control). All patients wore short-stretch high compression bandages. Parameters used to measure the effects of the treatments on the microcirculation were: TcPO2measurements, video laser Doppler measurements and the number of capillaries in the wound bed. The progression towards healing was measured by the reduction in ulcer area and formation of granulation tissue. The treatment period was four weeks.Results:Significant increases in TcPO2values were reported between baseline and week 4 for patients receiving the foam dressing only or the collagen plus foam dressing combination (p<0.008 versus p<0.003 respectively). There was also a significant increase in the number of capillaries for the collagen plus foam treatment only (p<0.002).Conclusion:This pilot study suggests that a moist wound environment stimulates perfusion of blood and oxygen to the wound tissue, thereby promoting angiogenesis. The collagen and foam dressing combination demonstrated superior results to the control and the foam dressing only. Monitoring the microcirculation may help to assess the effect of dressings on VLU healing, although more research is needed.Declaration of interest:This pilot study was supported by a limited grant from Lohmann & Rauscher GmbH, Germany.

•Surgical providers extensively use EMRs during and outside of working hours.•Encounters and time spent on EMR were high across all specialty and provider types.•Burnout is associated with increased use of electronic health records.•Opportunities to optimize time expended on EMR should be further explored.

Abstract: A mathematical analysis has been carried out on momentum and heat transfer characteristics in an incompressible electrically conducting viscoelastic boundary layer fluid flow over a linear stretching sheet. Momentum boundary layer equation takes into account the effect of transverse magnetic field and electric field. Thermal boundary layer equation takes into account the viscous dissipation and Ohmic dissipation due to transverse magnetic field and electric field. Highly non-linear momentum boundary layer equation and thermal boundary layer equation are converted into similarity equations and then solved numerically by employing fifth order Runge–Kutta–Fehlberg method with shooting. The results are analysed for the situation when stretching boundary is prescribed by non-isothermal temperature, namely, prescribed surface temperature (PST) which varies quadratically with the flow directional coordinate x. The effects of various physical parameters like viscoelastic parameter, Prandtl number, local Reynolds number, Eckert number Hartmann number and electric parameter on various momentum and heat transfers characteristics are analysed. Some of the important findings of this paper are (i) The combined effect of increasing the values of local Reynolds number and local electric parameter (E 1) is to decrease skin-friction coefficient C f largely. (ii) In presence of magnetic field the effect of electric field is to decrease temperature near the stretching boundary and increase the same significantly away from the stretching sheet. (iii) If electric field is present and the Prandtl number is lower then there would be a significant decrease of temperature near the boundary sheet in case of viscoelastic fluid. (iv) The presence of electric field reverses the direction of heat transfer on the boundary stretching sheet more significantly in case of viscoelastic fluid. [Copyright &y& Elsevier]

The electronic structure of a thin film of chlorine-substituted Zn-phthalocyanine (ZnPcCl 8) deposited on Ag(111) was studied by valence band photoemission and near-edge X-ray absorption fine structure spectroscopy. At the first stages of molecular adsorption the interface formation is accompanied by the promotion of intense interface states. A charge transfer from the substrate to lowest unoccupied molecular orbital (LUMO) of the molecules of the first layer appears as a new density of states close to the Fermi level in photoemission. The central role of the LUMO is corroborated by the reduction of the LUMO-derived transition observed in the low-coverage X-ray absorption spectrum taken at the N 1s edge. However, the lack of a sizable density of states at EFas well as the photon energy dependence of the interface state peak intensity suggest that more complicated mechanisms of intra- or extramolecular charge redistribution may also play a role. The Ag 4d-derived valence band region also appears strongly modified upon molecular adsorption. In the paper it is shown that these modifications are merely due to the vanishing of the substrate surface states and the emerging of a bulk density of states at the interface. It is suggested that such behavior should be common for other organic monolayers adsorbed on noble metal surfaces. Finally, the study of the work function as a function of coverage is presented. Its behavior is interpreted in terms of coexistence of different structural phases and compared to a local-probe work function study on the same system.

Let (A, T) be a locally A-pseudoconvex algebra over $${\mathbb{R}}$$ or $${\mathbb{C}}$$ . We define a new topology m(T) on Awhich is the weakest among all m-pseudoconvex topologies on Astronger than T. We describe a family of non-homogeneous seminorms on Awhich defines the topology m(T).

For the production of steel with an EAF (especially, also, for stainless steel, as shown at CORUS Engineering Steels in Stocksbridge), the RCB system of VAI FUCHS (Refining Combined Burner) represents an important step forward, in many respects, for the injection of oxygen. The constitution of the system, its working mode and its advantages are described. This innovative solution is already applied in the case of quite a number of furnaces.

The present paper deals with the study of momentum, heat and mass transfer characteristics in a viso-elastic fluid flow over a porous sheet, where the flow is generated due to linear stretching of the sheet and influenced by a uniform magnetic field applied vertically and a continuous injection of the fluid through porous boundary. In the flow region, heat balance is maintained with a temperature dependent heat source/sink, viscous dissipation, dissipation due to elastic deformation and stress work produced as the result of magnetic field on the non-Newtonian fluid. In mass transfer analysis we have taken into account the loss of mass of the chemically reactive diffusive species by means of first order chemical conversion rate. Using suitable similarity transformations on the highly non-linear partial differential equations we derive several closed form analytical solutions for non-dimensional temperature, concentration, heat flux, mass flux profiles in the form of confluent hyper geometric (Kummer's) functions and some other elementary functions as its special form, for two different cases of the boundary conditions, namely, (i) wall with prescribed second order power law temperature (PST) and prescribed second order power law concentration (ii) wall with prescribed second order power law heat flux (PHF) and prescribed second order power law mass flux. The effect of the non-dimensional magnetic parameter on momentum, heat and mass transfer characteristics for non-isothermal boundary condition and different physical situations of the fluid, having various degrees of visco-elasticity, Prandtl number, heat source/sink strength and Schmidt number, are discussed in detail. Some of the several important findings reported in this paper are: (i) The combined effect of magnetic field, visco-elasticity and impermeability of the wall is to increase skin-friction largely at the wall; (ii) maximum enhancement of wall-temperature profile due to the application of transverse magnetic field occurs when the boundary heating is maintained with prescribed heat flux, boundary wall is porous and Prandtl number of the fluid is low; (iii) the effect of transverse uniform magnetic field is to increase concentration in the flow region, however, enhancement of concentration is higher when the stretching wall is porous and subjected to injection and (iv) the reduction of concentration due to chemical conversion is of significant order near the wall in PHF case when the wall is maintained with prescribed power low mass flux, in comparison with the PST case when the wall is maintained with prescribed power law surface concentration.

Mit Ihren kühnen Y‐Pfeilern ist die Talbrücke über die Zahme Gera sowohl ästhetisch als auch ingenieurmäßig eine der anspruchsvollsten Brücken im Verlauf der Autobahn A 71/A 73 durch den Thüringer Wald. Aufgrund der Topographie und Geologie des Baugrundes waren unterschiedliche Gründungsformen für Widerlager, Pfeiler sowie Lehrgerüste erforderlich. Durch die außergewöhnliche Form der Pfeiler mußte zu deren Herstellung ein völlig neues Schalungssystem entwickelt und konstruiert werden. Der Beitrag stellt es vor. Zudem forderte das Bauwerk eine Reihe weiterer anspruchsvoller Baubehelfe wie Pfeilerabspannung und Justiereinrichtung für den Lückenschluß.

To investigate further brain‐pituitary‐gonadal interrelationships we have generated mice in which the gene encoding the FSH receptor has been disrupted (FSHRKO). FSHRKO females but not males are infertile. Compared with control animals, serum concentrations of LH and FSH and pituitary content of FSH are significantly increased in female FSHRKO (Abel et al. Endocrinology141, 2000). The aim of the present study was to correlate these physiological differences in gonadotroph function of 8‐week‐old‐female normal and FSHRKO mice with a structural analysis of their gonadotrophs. Gonadotrophs were identified by LH‐immunogold labeling for electron microscopy and gonadotroph frequency estimated from 1 (m sections immunolabelled for LH. In FSHRKO the frequency, cell and nuclear profile areas of gonadotrophs did not differ significantly from that in normal mice. Surprisingly the endoplasmic reticulum appeared normal and undilated despite the lack of oestradiol feedback in the KO animals. LH‐immunoreactive cells in female FSHRKO had significantly (P< 0.05) larger secretory granules 176(7 nm) diameter, mean(SEM) compared to normal mice 139(7 nm) but there was no significant difference in the granule area/cytoplasmic area. The subpopulation of granules in which an electron‐dense core was present in a more electron‐lucent ‘halo’ was absent in FSHRKO gonadotrophs. The increased pituitary FSH stores in FSHRKO mice therefore appear to be represented by the formation of larger secretory granules in which the packaging of hormone is less dense. Interestingly, despite being infertile and lacking biologically active estrogen, the alterations in FSHRKO pituitary morphology are relatively subtle compared to normal mice.

The PR-A and PR-B isoforms of progesterone receptors (PR) have different physiological functions, and their ratio varies widely in breast cancers. To determine whether the two PR regulate different genes, we used human breast cancer cell lines engineered to express one or the other isoform. Cells were treated with progesterone in triplicate, time-separated experiments, allowing statistical analyses of microarray gene expression data. Of 94 progesterone-regulated genes, 65 are uniquely regulated by PR-B, 4 uniquely by PR-A, and only 25 by both. Almost half the genes encode proteins that are membrane-bound or involved in membrane-initiated signaling. We also find an important set of progesterone-regulated genes involved in mammary gland development and/or implicated in breast cancer. This first, large scale study of PR gene regulation has important implications for the measurement of PR in breast cancers and for the many clinical uses of synthetic progestins. It suggests that it is important to distinguish between the two isoforms in breast cancers and that isoform-specific genes can be used to screen for ligands that selectively modulate the activity of PR-A or PR-B. Additionally, use of natural target genes, rather than "consensus" response elements, for transcription studies should improve our understanding of steroid hormone action.

Abstract:  In this paper we present a mathematical analysis of heat and mass transfer phenomena in a visco–elastic fluid flow over an accelerating stretching sheet in the presence of heat source/sink, viscous dissipation and suction/blowing. Similarity transformations are used to convert highly non-linear partial differential equations into ordinary differential equations. Several closed form analytical solutions for non-dimensional temperature, concentration, heat flux, mass flux profiles are obtained in the form of confluent hypergeometric (Kummer's) functions for two different cases of the boundary conditions, namely, (i) wall with prescribed second order power law temperature and second order power law concentration (PST), and (ii) wall with prescribed second order power law heat flux and second order power law mass flux (PHF). The effect of various physical parameters like visco–elasticity, Eckert number, Prandtl number, heat source/sink, Schmidt number and suction/blowing parameter on temperature and concentration profiles are analysed. The effects of all these parameters on wall temperature gradient and wall concentration gradient are also discussed.

Presents a numerical solution of the two-dimensional laminar boundary layer problem on free and forced convection of an incompressible visco-elastic fluid immersed in a porous medium over a stretching sheet. Here, the driving force for the flow is provided by an impermeable sheet stretched with a velocity proportional to the distance from a slit and buoyancy effects due to both temperature and concentration gradients. The resultant governing boundary layer equations are highly non-linear and coupled form of partial differential equations, and they have been solved by employing a numerical shooting technique with fourth order Runge-Kutta integration scheme. Numerical computations are carried out for the non-dimensional physical parameters. The results are analyzed for the effect of different physical parameters like visco-elasticity, permeability of the porous medium, Grashof number, Schmidt number and Prandtl number on the flow, heat and mass transfer characteristics. One of the several important observations is that the combined effect of thermal diffusion and diffusion of species is to increase the horizontal velocity profile and to decrease the temperature and concentration profiles in the boundary layer flow field. [ABSTRACT FROM AUTHOR]

Progesterone receptors (PR) contain three activation functions (AFs) that together define the extent to which they regulate transcription. AF1 and AF2 are common to the two isoforms of PR, PR-A and PR-B, whereas AF3 lies within the N-terminal 164 amino acids unique to PR-B, termed the “B-upstream segment” (BUS). To define the BUS regions that contribute to AF3 function, we generated a series of deletion and amino acid substitution mutants and tested them in three backgrounds as follows: BUS alone fused to the PR DNA binding domain (BUS-DBD), the entire PR-B N terminus linked to its DBD (NT-B), and full-length PR-B. Analyses of these mutants identified two regions in BUS whose loss reduces AF3 activity by more than 90%. These are associated with amino acids 54–90 (R1) and 120–154 (R2). R1 contains a consensus 55LXXLL59motif (L1) identical to ones found in nuclear receptor co-activators. R2 is adjacent to a second nuclear receptor box (L2) at115LXXLL119and contains a conserved tryptophan (Trp-140). Their mutation completely disrupts AF3 activity in a promoter and cell type-independent manner. Critical mutations elicited similar effects on all three B-receptor backgrounds. This underscores the probability that these mutations alter a process linking BUS structure to the function of full-length PR-B in a fundamental way.

The catalytic properties, with respect to the 1,3-butadiene hydrogenation reaction, of strained Pd films on Cu(110) (lattice mismatch 8%) has been probed as a function of the film thickness. The characterization of the adlayer has been made by the combined use of STM with LEED and AES. For deposits below 1015Pd/cm2(i.e., about 1 ML) the catalytic activity is near zero. This is the consequence of the formation of a Pd–Cu surface alloy with tendency for Cu to migrate/segregate to the surface. The catalytic activity suddenly increases to reach a maximum value for about 3 ML; the activity is then one order of magnitude higher than that of the pure Pd(110) surface. This is the consequence of the presence of a strained Pd overlayer, with Pd surface atoms having very unusual geometry, and hence very peculiar electronic and chemical properties. The catalytic activity then decreases as the Pd coverage is increased, and tends to values near that of the pure Pd(110). Gradual relaxation of the film geometry towards that of the “normal” fcc Pd structure probably exists.

Visco-elastic fluid flow and heat transfer in a porous medium over a non-isothermal stretching sheet have been investigated. The flow is influenced by linearly stretching the sheet in the presence of suction, blowing and impermeability of the wall. Thermal conductivity is considered to vary linearly with temperature. The intricate non-linear problem has been solved numerically by shooting technique with fourth order Runge-Kutta algorithm after using perturbation method. The zeroth order solutions are obtained analytically in the form of Kummer's function. An analysis has been carried out for two different cases, namely prescribed surface temperature (PST) and prescribed heat flux (PHF) to get the effect of porosity and visco-elasticity at various physical situations. The important finding is that the effect of visco-elasticity and porosity is to increase the wall temperature in case of blowing and to decrease in both the cases of suction and when the stretching sheet is impermeable. [ABSTRACT FROM AUTHOR]

Specimens treated with solutions of an epoxy analogue molecule, diethanolamine (DEA), have been studied by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF−SIMS). The initial substrates were of two different types:  grit-blasted aluminum and aluminum coated with an organosilane adhesion promoter, γ-glycidoxy propyl trimethoxy silane (GPS). Specific interactions between the aluminum substrate and/or GPS treated aluminum and DEA are proposed on the basis of XPS and SIMS data. On oxidized aluminum, DEA forms either a single alkoxy or two alkoxy bonds (bridge). The formation of the so-called bridge brings the nitrogen atom close to the substrate. The nitrogen atom of DEA interacts with the surface via formation of a hydrogen bond or via donor−acceptor interaction with an aluminum atom. When deposited onto GPS-coated aluminum, DEA undergoes two types of interactions:  formation of covalent bond with nucleophilic addition or Brönsted type of interaction between nitrogen of DEA and silanol functionality of hydrolyzed GPS.