Controlling Dynamic Stability and Active Compliance to Improve Quadrupedal Walking

Summary. It is widespread the idea that animal legged locomotion improves wheeled locomotion on very rough terrain. However, the use of legs as locomotion system for vehicles and robots is still far away from competing with wheels and trucks even on natural ground. Walking robots feature two main disadvantages. One is the lack of reacting capabilities from external disturbances, and the other is the very slow walking motion. Both obstacles prevent walking mechanisms from being introduced in industrial processes and from being part of service and assistance robotics. This paper is aimed at solving the two above obstacles by combining a dynamic stability margin that quantifies the impact energy that a robot can withstand, and either controlling a dynamic walk by means of active compliance, which helps the robot react to disturbances. Experiments performed on the SILO4 quadruped robot show a relevant improvement on the walking gait.This work has been partially funded by CICYT (Spain) through Grant DPI2004-05824. The first author is supported by a postdoctoral CSIC-I3P contract granted by the European Social Fund.Peer reviewe

Finished Genome of the Fungal Wheat Pathogen Mycosphaerella graminicola Reveals Dispensome Structure, Chromosome Plasticity, and Stealth Pathogenesis

The plant-pathogenic fungus Mycosphaerella graminicola (asexual stage: Septoria tritici) causes septoria tritici blotch, a disease that greatly reduces the yield and quality of wheat. This disease is economically important in most wheat-growing areas worldwide and threatens global food production. Control of the disease has been hampered by a limited understanding of the genetic and biochemical bases of pathogenicity, including mechanisms of infection and of resistance in the host. Unlike most other plant pathogens, M. graminicola has a long latent period during which it evades host defenses. Although this type of stealth pathogenicity occurs commonly in Mycosphaerella and other Dothideomycetes, the largest class of plant-pathogenic fungi, its genetic basis is not known. To address this problem, the genome of M. graminicola was sequenced completely. The finished genome contains 21 chromosomes, eight of which could be lost with no visible effect on the fungus and thus are dispensable. This eight-chromosome dispensome is dynamic in field and progeny isolates, is different from the core genome in gene and repeat content, and appears to have originated by ancient horizontal transfer from an unknown donor. Synteny plots of the M. graminicola chromosomes versus those of the only other sequenced Dothideomycete, Stagonospora nodorum, revealed conservation of gene content but not order or orientation, suggesting a high rate of intra-chromosomal rearrangement in one or both species. This observed “mesosynteny” is very different from synteny seen between other organisms. A surprising feature of the M. graminicola genome compared to other sequenced plant pathogens was that it contained very few genes for enzymes that break down plant cell walls, which was more similar to endophytes than to pathogens. The stealth pathogenesis of M. graminicola probably involves degradation of proteins rather than carbohydrates to evade host defenses during the biotrophic stage of infection and may have evolved from endophytic ancestors. Author Summary The plant-pathogenic fungus Mycosphaerella graminicola causes septoria tritici blotch, one of the most economically important diseases of wheat worldwide and a potential threat to global food production. Unlike most other plant pathogens, M. graminicola has a long latent period during which it seems able to evade host defenses, and its genome appears to be unstable with many chromosomes that can change size or be lost during sexual reproduction. To understand its unusual mechanism of pathogenicity and high genomic plasticity, the genome of M. graminicola was sequenced more completely than that of any other filamentous fungus. The finished sequence contains 21 chromosomes, eight of which were different from those in the core genome and appear to have originated by ancient horizontal transfer from an unknown donor. The dispensable chromosomes collectively comprise the dispensome and showed extreme plasticity during sexual reproduction. A surprising feature of the M. graminicola genome was a low number of genes for enzymes that break down plant cell walls; this may represent an evolutionary response to evade detection by plant defense mechanisms. The stealth pathogenicity of M. graminicola may involve degradation of proteins rather than carbohydrates and could have evolved from an endophytic ancestor

Genomic Organization, Splice Variants and Expression of CGMl, a CD66-related Member of the Carcinoembryonic Antigen Gene Family

The tumor marker carcinoembryonic antigen (CEA) belongs to a family of proteins which are composed of one immunogiobulin variable domain and a varying number of immunoglobulin constant-like domains. Most of the membrane-bound members, which are anchored either by a glycosylphosphatidylinositol moiety or a transmembrane domain, have been shown to convey cell adhesion in vitro. Here we describe two splice variants of CGMI. a transmembrane member of the CEA family without immunoglobulin constant.like domains. CGM1a and CGM1c contain cytopiasmic domains of 71 and 31 amino acids, respectively, The cytoplasmic region of CGM1a is encoded by four exons (Cyt1-Cyt4). Differential splicing of the Cyt1 exon (53 bp)..

Recovery of myocardial perfusion after percutaneous coronary intervention of chronic total occlusions is comparable to hemodynamically significant non-occlusive lesions.

BACKGROUND: The benefits of chronic coronary total occlusion (CTO) percutaneous coronary intervention (PCI) are being questioned. The aim of this study was to assess the effects of CTO PCI on absolute myocardial perfusion, as compared with PCI of hemodynamically significant non-CTO lesions. METHODS: Consecutive patients with a preserved left ventricular ejection fraction (≥50%) and a CTO or non-CTO lesion, in whom [15 O]H2 O positron emission tomography was performed prior and after successful PCI, were included. Change in quantitative (hyperemic) myocardial blood flow (MBF), coronary flow reserve (CFR) and perfusion defect size (in myocardial segments) were compared between CTOs and non-CTO lesions. RESULTS: In total 92 patients with a CTO and 31 patients with a non-CTO lesion were included. CTOs induced larger perfusion defect sizes (4.51 ± 1.69 vs. 3.23 ± 2.38 segments, P < 0.01) with lower hyperemic MBF (1.30 ± 0.37 vs. 1.58 ± 0.62 mL·min-1 ·g-1 , P < 0.01) and similarly impaired CFR (1.66 ± 0.75 vs. 1.89 ± 0.77, P = 0.17) compared with non-CTO lesions. After PCI both hyperemic MBF and CFR increased similarly between groups (P = 0.57 and 0.35) to normal ranges with higher hyperemic MBF values in non-CTO compared with CTO (2.89 ± 0.94 vs. 2.48 ± 0.73 mL·min-1 ·g-1 , P = 0.03). Perfusion defect sizes decreased similarly after CTO PCI and non-CTO PCI (P = 0.14), leading to small residual defect sizes in both groups (1.15 ± 1.44 vs. 0.61 ± 1.45 segments, P = 0.054). CONCLUSIONS: Myocardial perfusion findings are slightly more hampered in patients with a CTO before and after PCI. Percutaneous revascularization of CTOs, however, improves absolute myocardial perfusion similarly to PCI of hemodynamically significant non-CTO lesions, leading to satisfying results

Gerontechnologies for Home Support

No Abstract. This is an Edited book containing an introduction by the Authors (Moreno, Helal, Nap and Gutman), in addition to a number of articles curated and reviewed by the Authors with help provided by external reviewers

Mixed origin of neovascularization of human endometrial grafts in immunodeficient mouse models

peer reviewedBACKGROUND: In vivo mouse models have been developed to study the physiology of normal and pathologic endometrium. Although angiogenesis is known to play an important role in endometrial physiology and pathology, the origin of neovasculature in xenografts remains controversial. The aim of this study was to assess the origin of the neovasculature of endometrial grafts in different mouse models. METHODS: Human proliferative endometrium (n = 19 women) was grafted s.c. in two immunodeficient mouse strains: nude (n = 8) and severely compromised immunodeficient (SCID; n = 20). Mice were also treated with estradiol, progesterone or levonorgestrel. Fluorescence in-situ hybridization using a centromeric human chromosome X probe, immunohistochemistry (von Willebrand factor and collagen IV) and lectin perfusion were performed to identify the origin of the vessels. RESULTS: More than 90% of vessels within xenografts were of human origin 4 weeks after implantation. Some vessels (9.67 +/- 2.01%) were successively stained by human or mouse specific markers, suggesting the presence of chimeric vessels exhibiting a succession of human and murine portions. No difference in staining was observed between the two strains of mouse or different hormone treatments. Furthermore, erythrocytes were found inside human vessels, confirming their functionality. CONCLUSION: This article shows that human endometrial grafts retain their own vessels, which connect to the murine vasculature coming from the host tissue and become functional

Interventies in het aanbod van voedsel : aangrijpingspunten voor overheidsbeleid om het aanbod van gezonde voedselproducten structureel te verbeteren

In opdracht van de ministeries van LNV en VWS geeft dit rapport een aantal aanbod- en productgeoriënteerde interventies die door overheden toegepast kunnen worden om Nederlandse consumenten te verleiden tot gezonder eet- en leefgedrag. Achterliggend doel is om met kwalitatief beter voedsel en een beter consumptiepatroon een bijdrage te leveren aan de algemene gezondheidstoestan

Demographic differences between health care workers who did or did not respond to a safety and organizational culture survey

<p>Abstract</p> <p>Background</p> <p>Areas for institutional improvement to enhance patient safety are commonly identified by surveying health care workers' (HCWs) attitudes, values, beliefs, perceptions and assumptions regarding institutional practices. An ideal response rate of 100% is rarely achieved in such surveys, and non-response bias can occur when non-respondents differ from respondents on a dimension likely to influence survey conclusions. The conditions for non-response bias to occur can be detected by comparing demographic characteristics of respondents and non-respondents and relating any differences to findings in the literature of differences in the construct of interest as a function of these demographic characteristics. The current study takes this approach.</p> <p>Findings</p> <p>All 5,609 HCWs at a university medical center were invited to participate in a survey measuring safety and organizational culture (response rate = 53.40%). Respondents indicated their professional group, gender, age group, years of working in the hospital and executive function. Because all HCWs were invited, the demographic composition of the group who did not respond was known. Differences in the demographic composition of respondents and non-respondents were compared using separate Pearson's chi-square tests for each demographic characteristic.</p> <p>Nurses and clinical workers were generally more likely to respond than were physicians, laboratory workers and non-medical workers. Male HCWs were less likely to respond than were females, HCWs aged younger than 45 years old had a lower response rate than did HCWs aged 45 to 54 years old, HCWs who had worked in the hospital for less than 5 years were less likely to respond than were those who had worked in the hospital for 5 years or more and HCWs without an executive function were less likely to respond than were executives.</p> <p>Conclusions</p> <p>Demographic characteristics can be linked to response rates and need to be considered in conducting surveys among HCWs. The possibility of non-response bias can be reduced by conducting analyses separately as a function of relevant demographic characteristics, sampling a higher percentage of groups that are known to be less likely to respond, or weighting responses with the reciprocal of the response rate for the respective demographic group.</p

Tumor markers in breast cancer - European Group on Tumor Markers recommendations

Recommendations are presented for the routine clinical use of serum and tissue-based markers in the diagnosis and management of patients with breast cancer. Their low sensitivity and specificity preclude the use of serum markers such as the MUC-1 mucin glycoproteins ( CA 15.3, BR 27.29) and carcinoembryonic antigen in the diagnosis of early breast cancer. However, serial measurement of these markers can result in the early detection of recurrent disease as well as indicate the efficacy of therapy. Of the tissue-based markers, measurement of estrogen and progesterone receptors is mandatory in the selection of patients for treatment with hormone therapy, while HER-2 is essential in selecting patients with advanced breast cancer for treatment with Herceptin ( trastuzumab). Urokinase plasminogen activator and plasminogen activator inhibitor 1 are recently validated prognostic markers for lymph node-negative breast cancer patients and thus may be of value in selecting node-negative patients that do not require adjuvant chemotherapy. Copyright (C) 2005 S. Karger AG, Basel

Neurovasculature of high and low tie ligation of the inferior mesenteric artery

PURPOSE: Controversy exists as to whether a high or low tie ligation of the inferior mesenteric artery (IMA) is the preferred technique in surgeries of the left colon and rectum. This study aims to contribute to the discussion as to which is the more beneficial technique by investigating the neurovasculature at each site. METHODS: Ten embalmed cadaveric donors underwent division of the inferior mesenteric artery at the level of the low tie. The artery was subsequently ligated at the root to render a section of tissue for histological analysis of the proximal (high tie), mid and distal (low tie) segments. RESULTS: Ganglia observed in the proximal end of seven specimens in the sample imply that there would be disruption to the innervation in a high tie procedure. CONCLUSION: This study suggests that a high tie should be avoided if the low tie is oncologically viable