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Leptopirosis is a renal disease caused by pathogenic Leptospira that primarily infects the renal proximal tubules, consequently resulting in severe tubular injuries and malfunctions. The protein extracted from the outer membrane of this pathogenic strain contains a major component of a 32 kDa lipoprotein (LipL32), which is absent in the counter membrane of nonpathogenic strains and has been identified as a crucial factor for host cell infection. Previous studies showed that LipL32 induced inflammatory responses and interacted with the extracellular matrix (ECM) of the host cell. However, the exact relationship between LipL32-mediated inflammatory responses and ECM binding is still unknown. In this study, an atomic force microscope with its tip modified by purified LipL32 was used to assess the interaction between LipL32 and cell surface receptors. Furthermore, an antibody neutralization technique was employed to identify Toll-like receptor 2 (TLR2) but not TLR4 as the major target of LipL32 attack. The interaction force between LipL32 and TLR2 was measured as approximately 59.5 +/- 8.7 pN, concurring with the theoretical value for a single-pair molecular interaction. Moreover, transformation of a TLR deficient cell line with human TLR2 brought the interaction force from the basal level to approximately 60.4 +/- 11.5 pN, confirming unambiguously TLR2 as counter receptor for LipL32. The stimulation of CXCL8/IL-8 expression by full-length LipL32 as compared to that without the N-terminal signal peptide domain suggests a significant role of the signal peptide of the protein in the inflammatory responses. This study provides direct evidence that LipL32 binds to TLR2, but not TLR4, on the cell surface, and a possible mechanism for the virulence of leptospirosis is accordingly proposed.

In this paper, we present a low cost approach to produce large-area polymer sheets with sub-wavelength nanostructures. The fabricated polymer films would have great potentials to attach to optical or solar-cell-related consumer products when anti-reflection/anti-glaring is mandatory. We employed a special electron cyclotron resonance (ECR) plasma process to fabricate the SWSs with large area directly on silicon substrates. Homogeneously distributed nanotips on the full 4 inch silicon substrate were fabricated by using gas mixtures of silane, methane, argon and hydrogen. An Ni-Co metal mold with a hardness of 550 HV was produced through the replication of the Si mold by electroplating. Afterwards, the molding process was applied to manufacture the nanostructures in PMMA plates in large volume. The nanostructures in PMMA plates with aspect ratios of 4 and diameters of 150 nm were fabricated. The fabricated PMMA sheets could generate the gradient of the refractive indices, absorb the light and greatly reduce the reflectivity. Compared with the PMMA without SWSs, the reflectivity of PMMA with SWSs decreased dramatically from 4.25% to 0.5% at the wavelength of light from 400 to 800 nm.

Title: Magnetically Driven Micro Ball Valve Fabricated by Multilayer Adhesive Film Bonding A multilayer adhesive film bonding process was developed and a magnetically driven micro ball valve was designed and fabricated as a demonstrator using this new bonding method. The new bonding process uses adhesive films as bonding mediums. This bonding method can be applied to bond polymer housings, membrane and other different materials. The Taguchi method was used to find the proper process parameters to get enough bonding strength. The deformation of punched microstructures during each process step was analyzed in a statistical way. The sealing properties were tested with nitrogen and water solution. The compatibility with the AMANDA process was demonstrated by bonding separated membranes on polymer housings. The micro ball valve consists of three PSU and three FeNiCr layers, which are bonded together in one step with five punched adhesive films. The PSU layers were produced by hot embossing. Micro mechanical milling was employed to fabricate the molds needed. Laser cutting technology was selected to pattern FeNiCr layers demonstrating rapid prototyping. A small series production of approximately 50 micro ball valves was successfully realized in the laboratory. The valve can operate in two modes. One is an on-off switching mode and the other is a proportional mode. In the on-off switching mode, the valve switches the outlet pressure at two distinguished levels. The maximum switchable differential pressure of this valve is 200 kPa. The switch frequency was up to 30 Hz. In the proportional mode, controlling the ball position can regulate the outlet pressure. The magnetic force of the coil balances the forces of the flow and the weight of the ball. In this mode, the valve can steer the output pressure continuously in a range between 0 to 110 kPa, when the input pressure is 200 kPa. Inclination effects caused by the gravitation force were also investigated. The valve was found to be suitable for use at all inclination angles. The average leakage was measured to be approximately 0.3% of the flow through the open valve. Kurzfassung Kurzfassung Titel: Ein magnetisch gesteuertes Mikrokugelventil hergestellt durch das Verbindungsverfahren mehrschichtiger Klebfolien Ein Verbindungsprozess mit mehrschichtigen, klebfähigen Filmen wurde entwickelt, und ein magnetisch gesteuertes Mikrokugelventil wurde entworfen und mit diesem neuen Verbindungsprozess als Demonstrator hergestellt. Der neue Verbindungsprozess benutzt Klebfolien als Verbindungsmedium. Diese Methode kann für das Verbinden von Gehäuse und Membranen aus Polymeren und verschiedener anderer Materialien verwendet werden. Die Taguchi Methode wurde eingesetzt, um geeignete Prozessparameter für ausreichende Verbindungstärke zu finden. Die Verformung von gestanzten Mikrostrukturen in jedem Prozessschritt wurde statistisch analysiert. Die Versiegelungseigenschaften wurden mit Stickstoff und Wasserlösungen getestet. Die Kompatibilität mit dem AMANDA Prozess wurde durch das Verbind...

The detection of environmental temperature and regulation of body temperature are integral determinants of behaviour for all animals. These functions become less efficient in aged animals, particularly during exposure to cold environments, yet the cellular and molecular mechanisms are not well understood. Here, we identify an age-related change in the temperature preference of adult fruit flies that results from a shift in the relative contributions of two parallel mushroom body (MB) circuits—the β′- and β-systems. The β′-circuit primarily controls cold avoidance through dopamine signalling in young flies, whereas the β-circuit increasingly contributes to cold avoidance as adult flies age. Elevating dopamine levels in β′-afferent neurons of aged flies restores cold sensitivity, suggesting that the alteration of cold avoidance behaviour with ageing is functionally reversible. These results provide a framework for investigating how molecules and individual neural circuits modulate homeostatic alterations during the course of senescence.