Thermocouples easily installed in hard-to- get-to places

Thermocouple wires attached to charged capacitors are inserted in a drilled hole. An electric charge fuses the thermocouple wires to the host material. This method has shown excellent results in fusing nichrome, chromel, Inconel, and stainless steel wires to nickel, beryllium, iron, steel, Inconel, and stainless steel

Energy-Efficient Monopod Running with a Large Payload Based on Open-Loop Parallel Elastic Actuation

Despite the intensive investigations in the past, energetic efficiency is still one of the most important unsolved challenges in legged robot locomotion. This paper presents an unconventional approach to the problem of energetically efficient legged locomotion by applying actuation for spring mass running. This approach makes use of mechanical springs incorporated in parallel with relatively low-torque actuation, which is capable of both accommodating large payload and locomotion with low power input by exploiting self-excited vibration. For a systematic analysis, this paper employs both simulation models and physical platforms. The experiments show that the proposed approach is scalable across different payload between 0 and 150kg, and able to achieve a total cost of transport (TCOT) of 0.10, which is significantly lower than the previous locomotion robots and most of the biological systems in the similar scale, when actuated with the near-to natural frequency with the maximum payload.This study was supported by the Swiss National Science Foundation Grant No. PP00P2123387/1 and the Swiss National Science Foundation through the National Centre of Competence in Research Robotics

Aquaporins and Aquaglyceroporins of Legume Nodules: Structure, Function, and Regulation

By isolating RNA from mature nodules of the legume Lotus japonicas and employing an RT-PCR approach, two new cDNAs were characterized whose open reading frames code for members of the MIP (Major Intrinsic Protein) family of membrane proteins. These two genes products were termed (Lotus Intrinsic Membrane Protein 1 and 2) LIMP1 and LIMP2. Both LIMP1 and LIMP2 display all the hallmarks of the MIP protein family including, six putative transmembrane domains based on hydropathy plots, and the invariant NPA (asparagine-proline-alanine) signature motifs located symmetrically on two loops, which connect transmembrane helix 3-4 and transmembrane helix 5-6. Based on sequence information, LIMP1 is placed in the TIP (Tonoplast membrane Intrinsic Protein) subfamily of plant MIP proteins. Based on localization within the cells, TIPs are typically found on the tonoplast membrane of plant vacuoles. Functional characterization of LIMP1 by expression in Xenopus oocytes has demonstrated that it is a waterselective aquaporin. Using Northern blot techniques combined with immunolocalization, the expression patterns for LIMP1 were analyzed. The results indicate that LIMP1 is expressed predominately in nodules and roots. Based on Western blot analysis, however the highest LIMP1 protein levels are found in roots. LIMP1 appears to be regulated by diurnal cycling conditions, with expression increasing during the day hours, but falling off at the beginning of the night cycle. Increases in LIMP1 expression precedes the time of the diurnal cycle when the plant rate is the highest. This finding suggests that LIMP1, similar to other aquaporins, is regulated in response to the need for trancellular water uptake and transport from the soil during times of high transpiration stream activity. Although the LIMP2 protein shows some sequence similarity to LIMP1, it displays several features which distinguish it. Based on primary sequence identities, LIMP2 is classified in the plant NIP (Nodulin-like Intrinsic Protein) subfamily of MIP proteins which takes its name from the patriarch protein, nodulin 26. Nodulin 26 is a soybean nodule protein localized exclusively to the symbiosome membrane which surrounds the symbiotic bacteria during the nitrogen fixation process. Comparison of the LIMP2 protein sequence with other MIP family members shows that it shares the highest sequence identity (68%) with nodulin 26. In addition to structural similarity, nodulin 26 and LIMP2 also share the ability to facilitate the transport of water as well as small uncharged solutes (e.g. glycerol) upon expression in Xenopus oocytes. Analysis of the tissue distribution of LIMP2 by Northern blot and immunolocalization reveal that the LIMP2 transcript is expressed only in nodule tissue and that this protein, like nodulin 26, is present on the symbiosome membrane. LIMP2 and LIMP1 both show the ability to transport water, but the rate of transport is several-fold lower than that observed for high water transport MIP proteins such as mammalian aquaporin 1 (AQP1). Based on the crystal structures of AQP1 and the bacterial glycerol facilitator protein (GlpF), models of the selectivity filter for LIMP1 and LIMP2 were generated and analyzed in order to resolve the underlying characteristics for these observed differences. The proposed selectivity filter for LIMP2 displays a pore large enough to accommodate the passage of glycerol. Further, three key residues, a tryptophan in helix 2 and a valine in helix 5 and an arginine in the second NPA loop, form an amphipathic signature similar to the selectivity filter of the glyceroporin GlpF and are proposed to account for the glycerol permeability of nodulin 26 and LIMP2. In silica modeling of the predicted pore for LIMP1/TIPs shows a unique set of features. It shows a higher hyrdrophobic character than AQP1 and unusual substitutions, a histidine in helix 2 which replaces an invariant phenylalanine, an isoleucine in helix 5 which substitutes for a histidine, and a valine in the second NPA loop which substitutes for an invariant arginine. These substitutions suggest that the pore structure of LIMP1 is quite unlike the two models (AQP1 and GlpF), and further insight into factors that contribute to its rate and selectivity will have to await more detailed structural analysis. In addition to sequence and functional similarities, both nodulin 26 and LIMP2 share a conserved phosphorylation motif for CDPK (Calcium Dependent Protein Kinase) located on the cytosolic carboxyl terminal tail. In vitro assays using the carboxyl terminal sequence of LIMP2 suggest that similar to nodulin 26, it is phosphorylated by CDPK and is likely a target for calcium-dependent phosphorylation. Using an antibody which specifically recognizes the phosphorylated form of nodulin 26, a developmental pattern of phosphorylation is observed, where immature nodules show no or very low levels of phosphorylation and very old nodules show no phosphorylation of nodulin 26 although the protein is present in both young and old nodules at the same level as in mature nodules. Using this phosphorylation-specific antibody it was also determined that in mature soybean nodules the inherent level of phosphorylation is stimulated in response to osmotic stress (drought and salinity). Taken together, these results show that Lotus japonicus nodules have two MIP proteins. LIMP1 is a member of the TIP family of plant MIP proteins which is found predominately in root tissues where it forms a water selective channel, and its expression is controlled by diurnal variation. Its role in roots and nodules remains unknown, but it could play a role in transcellular water flow and cell volume regulation as proposed for other TIPs. In contrast, LIMP2 appears to be the Lotus japonicus ortholog of nodulin 26, an aquaglyceroporin that is localized on the symbiosome. LIMP2 and nodulin 26 are phosphorylated and likely regulated by calcium signaling through a symbiosome membrane CDPK. Previous studies show that phosphorylation of nodulin 26 enhances its water permeability. The present work suggests that phosphorylation by a calcium-dependent kinase is stress regulated and that phosphorylation of nodulin 26 may be among the osmoregulatorry responses of nodules necessary for stress adaptation, possibly by facilitating rapid water/solute flow to buffer the infected cell cytosol and symbiosome to fluctuations in osmotic gradients

Bypassing the bandwidth theorem with PT symmetry

The beat time {\tau}_{fpt} associated with the energy transfer between two coupled oscillators is dictated by the bandwidth theorem which sets a lower bound {\tau}_{fpt}\sim 1/{\delta}{\omega}. We show, both experimentally and theoretically, that two coupled active LRC electrical oscillators with parity-time (PT) symmetry, bypass the lower bound imposed by the bandwidth theorem, reducing the beat time to zero while retaining a real valued spectrum and fixed eigenfrequency difference {\delta}{\omega}. Our results foster new design strategies which lead to (stable) pseudo-unitary wave evolution, and may allow for ultrafast computation, telecommunication, and signal processing.Comment: 5 pages, 3 figure

Energy-Efficient Monopod Running with a Large Payload Based on Open-Loop Parallel Elastic Actuation

Despite the intensive investigations in the past, energetic efficiency is still one of the most important unsolved challenges in legged robot locomotion. This paper presents an unconventional approach to the problem of energetically efficient legged locomotion by applying actuation for spring mass running. This approach makes use of mechanical springs incorporated in parallel with relatively low-torque actuation, which is capable of both accommodating large payload and locomotion with low power input by exploiting self-excited vibration. For a systematic analysis, this paper employs both simulation models and physical platforms. The experiments show that the proposed approach is scalable across different payload between 0 and 150kg, and able to achieve a total cost of transport (TCOT) of 0.10, which is significantly lower than the previous locomotion robots and most of the biological systems in the similar scale, when actuated with the near-to natural frequency with the maximum payload.This study was supported by the Swiss National Science Foundation Grant No. PP00P2123387/1 and the Swiss National Science Foundation through the National Centre of Competence in Research Robotics

Does living in human-altered environments affect life-history and personality of wild mice?

In urban habitats, animals are faced with different and often challenging environmentalconditions compared to their native habitats. Behavior is the fastest responseto environmental change and therefore a very important component to adjust tohuman-altered environments. Behaviors such as novelty responses and innovativenesswhich allow animals to cope with novel stimuli are often altered in urban populations.The mechanisms producing such adaptations are currently not well understood. Inthis study, we investigate whether urban living has an impact on the microevolutionof mouse behavioral and life-history traits including boldness, stress-coping, growth,longevity, and emphasis on reproduction. We hypothesized that animals living togetherwith humans for longer show increased novelty-seeking and boldness characteristicsat the species and subspecies level. We, therefore, compared behavior and lifehistory characteristics amongMus musculus, a commensal rodent,Mus spicilegusas a synanthropic but not commensal, andApodemus uralensisas a strictly ruralspecies. In addition, we compared three subspecies ofM. musculus(in total sixpopulations) that differ in the time living together with humans. Behavioral and lifehistory differences are stronger between populations even of the same subspeciesrather than showing a structural trend with the time animals have spent with humans. Inaddition, species differ in behavior and life history, albeit not in a pattern that suggests anevolutionary adaptation to living in human-altered habitats. We, therefore, suggest thatbehavioral adaptations of wild mice are geared toward environmental differences suchas geographic origin or habitat specifics but not necessarily directly evolve by livingtogether with humans

Microbial risk factors of cardiovascular and cerebrovascular diseases: potential therapeutic options

Infection and inflammation may have a crucial role in the pathogenesis of atherosclerosis. This hypothesis is supported by an increasing number of reports on the interaction between chronic infection, inflammation, and atherogenesis. Assessment of serological and inflammatory markers of infection may be useful adjuncts in identifying those patients who are at a higher risk of developing vascular events, and in whom more aggressive treatments might be warranted