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Surface coatings prepared by layer‐by‐layer technique permit loading of growth factors (GFs) and their spatially controlled release. Here, native chondroitin sulfate (nCS), oxidized CS (oCS100), or mixture of both (oCS50) are combined with collagen I (Col I) to fabricate polyelectrolyte multilayers (PEMs) that exhibit structural, mechanical, and biochemical cues like the natural extracellular‐matrix. The use of oCS enables intrinsic cross‐linking of PEM that offers higher stability, stiffness, and better control of bone morphogenetic protein‐2 (BMP‐2) release compared to nCS. oCS100 PEMs have enhanced stiffness, promote Col I fibrillization, and present BMP‐2 in a matrix‐bound manner. oCS50 PEMs show intermediate effects on osteogenesis, soft surface, high water content but also moderately slow BMP‐2 release profile. C2C12 myoblasts used for osteogenesis studies show that oCS PEMs are more stable and superior to nCS PEMs in supporting cell adhesion and spreading as well as in presenting BMP‐2 to the cells. oCS PEMs are triggering more osteogenesis as proved by the quantitative real‐time polymerase chain reaction, immune and histochemical staining. These findings show that intrinsic cross‐linking in oCS/Col I multilayers provides a successful tool to control GFs delivery and subsequent cell differentiation which opens new opportunities in regenerative therapies of bone and other tissues. [ABSTRACT FROM AUTHOR]

Byline: Matthias Menzel (1), Jens Soukup (1), Dirk Henze (1), Kai Engelbrecht (1), Maik Senderreck (1), Alexander Scharf (1), Andreas Rieger (1), Stefan Grond (1) Keywords: Continuous monitoring; Intra-arterial blood gas analysis; Optodes; Oxygen measurement Abstract: Objective The utility of continuous intra-arterial blood gas analysis (CBGA) with combined electrochemical and optode sensors has been demonstrated. More recently, a pure optode sensor with a changed sensing element architecture has become available. The aim was to determine the measurement accuracy and long-term stability of the new sensor. Design A prospective explorative study was performed. Simultaneous measurements of intermittent blood gas analyses (IBGA) (ABL 610, Radiometer, Copenhagen) and CBGA (Diametrics Medical, High Wycombe, Bucks., UK) were compared using Bland-Altman analysis. Patients Twenty-five patients admitted to the ICU and requiring mechanical ventilation for an expected minimum of about 96 h were included. Results Mean monitoring time was 106.1 (range 15--231) hours. Bias and precision for P[O.sub.2 ]were -0.2 kPa (1%)+-1.8 kPa (9.5%) PCO.sub.2: 0.03 kPa (0.6%)+-0.44 kPa (9.3%) pH: -0.001 (0.01%)+-0.04 (0.45%). The sensor showed no change of measurement characteristics during 4 days of measurement. However, in 69 cases continuous monitoring was interrupted (reversible sudden drops of PO.sub.2 measurement) possibly caused by thrombotic deposition and/or sensor bending and accidental sensor retraction. Conclusions The precision and bias of the PCO.sub.2- and pH-sensing elements were in line with the findings of the older sensor technology. The possibility that the PO.sub.2 optode could offer greater accuracy than the older technology is suggested by comparisons with results reported in previous studies. No sensor drift occurred during long-term measurement over more than 4 days. Author Affiliation: (1) Dept. of Anesthesiology and Intensive Care Medicine, Martin-Luther-University, Magdeburger Strasse 16, 06097, Halle, Germany Article History: Received Date: 09/01/2003 Accepted Date: 22/07/2003 Online Date: 03/09/2003

Background: Prevention of inadvertent hypothermia is recommended for procedures >30 minutes because hypothermia increases the risk of myocardial ischemia, intraoperative blood loss, transfusion and wound complications. Therefore, short warming interruptions between pre-warming and intraoperative warming might result in lower hypothermia rates. The aim of this retrospective investigation was to determine whether the incidence of inadvertent intraoperative hypothermia was affected by the warming interruption.Methods: The lowest intraoperative body core temperature value and the warming interruption time were taken from anaesthesia records. Body core temperature was recorded continuously, and a patient was classified to be hypothermic if the lowest recorded temperature value was <36°C. Hypothermia rates and the correlation between warming interruption times and intraoperative hypothermia rates were calculated.Results: Five thousand eighty-four patients were analysed. The intraoperative hypothermia rate was 15.3%. Nineteen patients (0.4%) had a recorded temperature of <35.0°C. An increase in forced-air warming interruption time was significantly associated with an increase in intraoperative hypothermia rates (P < .0001). Patients with interruptions in forced-air warming >20 minutes showed significantly higher hypothermia rates than those with interruptions of ≤20 minutes (P < .0001).Conclusion: Intraoperative hypothermia rates increased significantly with longer forced-air warming interruptions between pre-warming and intraoperative warming. Short warming interruptions can preserve the effect of pre-warming and are associated with low intraoperative hypothermia rates. [ABSTRACT FROM AUTHOR]

Summary: To avoid pathogen‐associated molecular pattern recognition, the hemibiotrophic maize pathogen Colletotrichum graminicola secretes proteins mediating the establishment of biotrophy. Targeted deletion of 26 individual candidate genes and seven gene clusters comprising 32 genes of C. graminicola identified a pathogenicity cluster (CLU5) of five co‐linear genes, all of which, with the exception of CLU5b, encode secreted proteins. Targeted deletion of all genes of CLU5 revealed that CLU5a and CLU5d are required for full appressorial penetration competence, with virulence deficiencies independent of the host genotype and organ inoculated. Cytorrhysis experiments and microscopy showed that Δclu5a mutants form pressurized appressoria, but they are hampered in forming penetration pores and fail to differentiate a penetration peg. Whereas Δclu5d mutants elicited WT‐like papillae, albeit at increased frequencies, papillae induced by Δclu5a mutants were much smaller than those elicited by the WT. Synteny of CLU5 is not only conserved in Colletotrichum spp. but also in additional species of Sordariomycetes including insect pathogens and saprophytes suggesting importance of CLU5 for fungal biology. Since CLU5a and CLU5d also occur in non‐pathogenic fungi and since they are expressed prior to plant invasion and even in vegetative hyphae, the encoded proteins probably do not act primarily as effectors. [ABSTRACT FROM AUTHOR]

The stability of nonpatterned and nanopatterned strong polyelectrolyte brushes (PEBs) is studied as a function of both brush character and the properties of a contacting liquid. High‐molecular‐weight PEBs of poly(4‐methyl vinylpyridinium iodide) (PMeVP) are synthesized using surface‐initiated radical‐chain polymerization. Nanopatterned brushes (NPBs) line with pattern sizes ranging from 50 to 200 nm are generated by patterning the initiator layer using deep‐ultraviolet photolithography followed by brush growth initiated from the patterned layer. Homogeneous PEBs with different degrees of charging and grafting densities are exposed to water and salt solutions with different temperatures for different periods. The degradation is monitored through dry‐state ellipsometry and atomic force microscopy measurements. Enhanced degrafting for more strongly swollen polymer brushes can be observed in agreement with an "entropic spring" model. Based on the results of the nonpatterned brushes, the NPBs are exposed to water at different temperatures and external salt content for varying periods of time. Counterintuitively, the NPBs show increased degrafting for smaller patterns, which is attributed to different polymer chain dynamics for nanobrushes and microbrushes. We investigate the influence of thermodynamic and kinetic parameters on the stability of (nanopatterned) PEBs and discuss the role of entanglements and formation of complexes in such films. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1283–1295 [ABSTRACT FROM AUTHOR]

The morphology of top-down and bottom-up nanostructured neutral brushes is studied as a function of the production process and the quality of solvent to which the brushes have been exposed. Neutral brushes of poly(tert-butyl methacrylate) (PtBuMA) were grafted from the substrate by surface-initiated radical-chain polymerization (SI-RCP). Brush patterning was conducted using deep ultraviolet (DUV) photolithography following either top-down (TD) or bottom-up (BU) approaches with patterned lines as small as 200 nm. The resulting brushes were immersed in toluene or methanol, and the change of morphology of the dried brushes was monitored using tapping mode atomic force microscopy (AFM). TD nanopatterned brushes (NPBs) exhibit a box-like and BU generated brushes a lens-like shape directly after the production process. We show that the pattern width for the BU brushed depends not only on the wetting properties of the areas adjacent to the pattern but also on the process history to which the sample has been exposed, especially the solvent quality. Furthermore, we show that TD NPBs are cross-linked on the edges of the pattern because of the high-energy process conditions during brush patterning and study the behavior of the thus-obtained structures. [ABSTRACT FROM AUTHOR]

The stability of strong polyelectrolyte brushes (PEBs) was studied in bulk and in patterned structures. Thick PEBs of poly([(2-methacryloyloxy)ethyl]trimethylammonium chloride) with thicknesses >100 nm were synthesized using single electron transfer living radical polymerization. Brush patterning was identified using deep-ultraviolet photolithography by means of either a top-down (TD) or bottom-up (BU) method, with features as small as 200 nm. The brushes were soaked in water under a range of pH or temperature conditions, and the hydrolysis was monitored through dry-state ellipsometry and atomic force microscopy measurements. BU patterns showed reduced degrafting for smaller patterns, which was attributed to increased stress relaxation at such dimensions. In contrast to the already relaxed BU-patterned brush, a TD-patterned brush possesses perpendicular structures that result from the use of orthogonal lithography. It was found that the TD process induces cross-linking on the sidewall, which subsequently fortifies the sidewall materials. This modification of the polymer brushes hindered the stress relaxation of the patterns, and the degrafting trends became irrelevant to the pattern sizes. With proper tuning, the cross-linking on the sidewall was minimized and the degrafting trends were again relaxation-dependent. [ABSTRACT FROM AUTHOR]

Background: Spider silk is a tear-resistant and elastic biopolymer that has outstanding mechanical properties. Additionally, exiguous immunogenicity is anticipated for spider silks. Therefore, spider silk represents a potential ideal biomaterial for medical applications. All known spider silk proteins, so-called spidroins, reveal a composite nature of silk-specific units, allowing the recombinant production of individual and combined segments. Results: In this report, a miniaturized spidroin gene, named VSO1 that contains repetitive motifs of MaSp1 has been synthesized and combined to form multimers of distinct lengths, which were heterologously expressed as elastin-like peptide (ELP) fusion proteins in tobacco. The elastic penetration moduli of layered proteins were analyzed for different spidroin-based biopolymers. Moreover, we present the first immunological analysis of synthetic spidroin-based biopolymers. Characterization of the binding behavior of the sera after immunization by competitive ELISA suggested that the humoral immune response is mainly directed against the fusion partner ELP. In addition, cytocompatibility studies with murine embryonic fibroblasts indicated that recombinant spidroin-based biopolymers, in solution or as coated proteins, are well tolerated. Conclusion: The results show that spidroin-based biopolymers can induce humoral immune responses that are dependent on the fusion partner and the overall protein structure. Furthermore, cytocompatibility assays gave no indication of spidroin-derived cytotoxicity, suggesting that recombinant produced biopolymers composed of spider silk-like repetitive elements are suitable for biomedical applications. [ABSTRACT FROM AUTHOR]

The degradation of 405-nm fiber-coupled diode laser systems with more than 50 mW power was investigated in detail with focus on the effects occurring at the input end. The coupling and transmission loss of the laser light were associated with the growth of a projection and a periodic structure on the input surface. To avoid this degradation, a short launch fiber with a good surface quality was used at the input end. In this way, the power transmission was stabilized for at least one month. However, structural degradation was noticed on the output surface of the single-mode fiber. To investigate this effect, the damaged samples weremeasured after different periods of time and examined with a scanning electron microscope and with an atomic force microscope. Reproducible spherical projections with a submicron periodic structure were found in the core region. Additionally, the spectral loss of the fiber was measured, showing the formation of color centers in the deep ultraviolet along the length of the fiber. These investigations were accompanied by simulations of the growth of the structure on the output surface. The influence of the structure was mainly on the divergence angle of the emitted laser beam, reducing the beam quality for applications. [ABSTRACT FROM AUTHOR]

Phytophenols are considered to have beneficial effects towards human physiology. They are food microcomponents with potent chemopreventive properties towards the most three frequent contemporary human diseases, e.g., cardiovascular alterations, cancer and neurodegenerative pathologies. Related to this, the plasmatic form and plasmatic level of plant polyphenols in the body circulation are crucial for their efficiency. Thus, determinations of the binding process of resveratrol and of common flavonoids produced by major edible plants, berries and fruits to plasma proteins are essential. The interactions between resveratrol and albumin, a major plasma protein, were compared with those already published, involving curcumin, genistein, quercetin and other well-known food-containing polyphenols. The approaches used are usually intrinsic fluorescence intensity changes, quenching of protein intrinsic fluorescence and infrared spectroscopy. It appears that: (1) all of the studied polyphenols interact with albumin; (2) while most of the studied polyphenols interact at one albumin binding site, there are two different types of resveratrol binding sites for bovine serum albumin, one with the highest affinity (apparent KD of 4 µM) with a stoichiometry of one per monomer and a second with a lower affinity (apparent KD of 20 µM) with also a stoichiometry of one per monomer; (3) at least one binding site is in the vicinity of one tryptophanyl residue of bovine serum albumin; and (4) resveratrol binding to bovine serum albumin produces a very small structural conformation change of the polypeptide chain. These results support a role played by polyphenols-albumin interactions in the plasma for the bio-activities of these food microcomponents in the body. [ABSTRACT FROM AUTHOR]

High retention forces are the basic requirements on stretch films for agricultural or pallet wrapping of goods and significantly influenced by cling properties (autohesion) that are essential for a reliable load stability during transportation and storage. Low molecular weight polyisobutylene (PIB) has tacky properties and is immiscible with polyethylene. Blended with ethylene/α-olefin copolymers in coextruded stretch films, PIB can migrate to the film surfaces and cause cling properties. Cling and adhesion forces were investigated using the mechanical cling test, atomic force, and scanning electron microscopy and infrared spectroscopy. The molecular weight of the PIB as well as density and crystallinity of the matrix material have strong influences on migration kinetics and therefore, on the cling forces. Cling forces increase with increasing aging time, having a maximum after 2 weeks of production. The following slight decrease of the cling force might be correlated with a beginning degradation process of the UV sensitive PIB. Polyisobutylene with higher molecular weight diffuses slower through a linear low density polyethylene (LLDPE) matrix than lower molecular weight PIB, but can cause higher cling forces on the film surfaces. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40239. [ABSTRACT FROM AUTHOR]

In the last two decades it was shown that plants have a great potential for production of specific heterologous proteins. But high cost and inefficient downstream processing are a main technical bottleneck for the broader use of plant-based production technology especially for protein-based products, for technical use as fibres or biodegradable plastics and also for medical applications. High-performance fibres from recombinant spider silks are, therefore, a prominent example. Spiders developed rather different silk materials that are based on proteins. These spider silks show excellent properties in terms of elasticity and toughness. Natural spider silk proteins have a very high molecular weight, and it is precisely this property which is thought to give them their strength. Transgenic plants were generated to produce ELPylated recombinant spider silk derivatives. These fusion proteins were purified by Inverse Transition Cycling ( ITC) and enzymatically multimerized with transglutaminase in vitro. Layers produced by casting monomers and multimers were characterized using atomic force microscopy ( AFM) and AFM-based nanoindentation. The layered multimers formed by mixing lysine- and glutamine-tagged monomers were associated with the highest elastic penetration modulus. [ABSTRACT FROM AUTHOR]

The magnetic ground state of biatomic Fe chains on the reconstructed (5×1)-Ir(001) surface is a cycloidal 120° spin spiral. Spin-resolved scanning tunneling microscopy reveals a striking variation of magnetic field dependences among the chains, which we attribute to parity effects resulting from finite lengths. Numerical simulations show that the chains are divided in three symmetry classes with the exact number of atoms in the chain determining the size and direction of their net magnetic moment. In contrast to antiferromagnetic systems, the three-atom periodicity causes the effective anisotropy to alternate between out of plane, in plane, and quenched. [ABSTRACT FROM AUTHOR]

High-voltage and high-current SiC bipolar diode modules are fabricated and characterized under static and dynamic conditions. The modules are built using 6 \times 6\ \mm^2 SiC chips that are fabricated on 3-in SiC substrates. Individual chips were also packaged in an ISOPLUS™ package and used to perform switching tests on the diodes. The modules have been fully characterized under static and dynamic conditions. These modules are targeted for high-voltage high-frequency applications as well as antiparallel diodes for 6.5-kV insulated gate bipolar transistors, insulated gate commutated thyristors, and injection enhanced insulated gate bipolar transistors. [ABSTRACT FROM AUTHOR]

Vector spin chirality is one of the fundamental characteristics of complex magnets. For a one-dimensional spin-spiral state it can be interpreted as the handedness, or rotational sense of the spiral. Here, using spin-polarized scanning tunneling microscopy, we demonstrate the occurrence of an atomic-scale spin spiral in finite individual bi-atomic Fe chains on the (5 X 1) -- Ir(001) surface. We show that the broken inversion symmetry at the surface promotes one direction of the vector spin chirality, leading to a unique rotational sense of the spiral in all chains. Correspondingly, changes in the spin direction of one chain end can be probed tens of nanometers away, suggesting a new way of transmitting information about the state of magnetic objects on the nanoscale. [ABSTRACT FROM AUTHOR]