Bio-inspired swing leg control for spring-mass robots running on ground with unexpected height disturbance

We proposed three swing leg control policies for spring-mass running robots, inspired by experimental data from our recent collaborative work on ground running birds. Previous investigations suggest that animals may prioritize injury avoidance and/or efficiency as their objective function during running rather than maintaining limit-cycle stability. Therefore, in this study we targeted structural capacity (maximum leg force to avoid damage) and efficiency as the main goals for our control policies, since these objective functions are crucial to reduce motor size and structure weight. Each proposed policy controls the leg angle as a function of time during flight phase such that its objective function during the subsequent stance phase is regulated. The three objective functions that are regulated in the control policies are (i) the leg peak force, (ii) the axial impulse, and (iii) the leg actuator work. It should be noted that each control policy regulates one single objective function. Surprisingly, all three swing leg control policies result in nearly identical subsequent stance phase dynamics. This implies that the implementation of any of the proposed control policies would satisfy both goals (damage avoidance and efficiency) at once. Furthermore, all three control policies require a surprisingly simple leg angle adjustment: leg retraction with constant angular acceleration

Induced demand: A challenge on the way of Iran Health Revolution Program

By comparing indefinite demand and definite resources during the time, induced demand leads to an increase in the share of people in health costs. This may turn into a critical challenge in health system if not managed appropriately. The aim of the current study is to explain the different dimensions of influential factors in induced demand. In addition, changes in induced demand from the beginning of its implementation in the health program are studies as well. This study was carried out through semi-structured interviews with the managers of health care system in Isfahan Province, Iran, which offer health service in three levels: first, second, and third. After the implementation of seven packages of Health Revolution Program, four fundamental concepts of influential fundamental and social factors in induced demand, the organizational structure, and interested parties were studied in 2015. Our findings show that the health Revolution Program has caused an increase in induced demand through social factors (incremental demand, physician-centered system), fundamental factors (lost influence of Referral and Family Physician Programs),the organizational structure(weakness in the educational system, ignoring medicine ethics, lack of regulatory programs), and interested parties (suppliers and receivers). Induced demand increases the affordable costs index. This, in turn, influences the positive acquired results of the program and decreases effective allocation of national resources. This can be managed using such strategies as improving managers' insight about supporting induced demand control, appropriate planning in health care system, correcting the educational system in the field of health care, correcting the payment and referral systems

Mechanisms of Direct Reprogramming of Human Astrocytes To Induced-Neurons

Trans-differentiation of cells into induced-neurons is a promising strategy for CNS repair after acute injury or neurodegenerative diseases. Astrocytes are an ideal cell source for direct neuronal conversion. The purpose of the present study is the investigation of the neuronal reprogramming capacity of Cend1 and/or Neurog2, upon their overexpression on primary human adult cortical astrocytes. The newborn induced-neurons were studied for their morphology and molecular phenotype at specific time points after transgene overexpression. The astrocytes are reprogrammed by either CEND1 or NEUROG2 directly to cells with differentiated neuronal morphology, exhibiting long neurites and branched processes. Induced neurons exhibit either GABAergic (CEND1 overexpression) or Glutamatergic/dopaminergic (NEUROG2 overexpression) molecular phenotype. Exploration of gene expression dynamics along the entire conversion process revealed that neuronal genes are significantly up-regulated while astrocytic genes are down-regulated. On the other hand, in double-trasnsduced cultures, the levels of relative expression of neural progenitor/stem genes are high and this comes in accordance with the appearance of highly proliferative spheres with neural progenitor cell (NPC) properties in culture.Trans-differentiation of cells into induced-neurons is a promising strategy for CNS repair after acute injury or neurodegenerative diseases. Astrocytes are an ideal cell source for direct neuronal conversion. The purpose of the present study is the investigation of the neuronal reprogramming capacity of Cend1 and/or Neurog2, upon their overexpression on primary human adult cortical astrocytes. The newborn induced-neurons were studied for their morphology and molecular phenotype at specific time points after transgene overexpression. The astrocytes are reprogrammed by either CEND1 or NEUROG2 directly to cells with differentiated neuronal morphology, exhibiting long neurites and branched processes. Induced neurons exhibit either GABAergic (CEND1 overexpression) or Glutamatergic/dopaminergic (NEUROG2 overexpression) molecular phenotype. Exploration of gene expression dynamics along the entire conversion process revealed that neuronal genes are significantly up-regulated while astrocytic genes are down-regulated. On the other hand, in double-trasnsduced cultures, the levels of relative expression of neural progenitor/stem genes are high and this comes in accordance with the appearance of highly proliferative spheres with neural progenitor cell (NPC) properties in culture

Association between Randall's Plaque and Calcifying Nanoparticles

Randall's plaques, first described by Alexander Randall in the 1930s, are small subepithelial calcifications in the renal papillae (RP) that also extend deeply into the renal medulla. Despite the strong correlation between the presence of these plaques and the formation of renal stones, the precise origin and pathogenesis of Randall s plaque formation remain elusive. The discovery of calcifying nanoparticles (CNP) and their detection in many calcifying processes of human tissues has raised hypotheses about their possible involvement in renal stone formation. We collected RP and blood samples from 17 human patients who had undergone laparoscopic nephrectomy due to neoplasia. Homogenized RP tissues and serum samples were cultured for CNP. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis were performed on fixed RP samples. Immunohistochemical staining (IHS) was applied on the tissue samples using CNP-specific monoclonal antibody (mAb). Randall s plaques were visible on gross inspection in 11 out of 17 collected samples. Cultures of all serum samples and 13 tissue homogenates had CNP growth within 4 weeks. SEM revealed spherical apatite formations in 14 samples, with calcium and phosphate peaks detected by EDS analysis. IHS was positive in 9 out of 17 samples. A strong link was found between the presence of Randall s plaques and the detection of CNP, also referred to as nanobacteria. These results suggest new insights into the etiology of Randall's plaque formation, and will help us understand the pathogenesis of stone formation. Further studies on this topic may lead us to new approaches on early diagnosis and novel medical therapies of kidney stone formation

Don't break a leg: Running birds from quail to ostrich prioritise leg safety and economy in uneven terrain

Cursorial ground birds are paragons of bipedal running that span a 500-fold mass range from quail to ostrich. Here we investigate the task-level control priorities of cursorial birds by analysing how they negotiate single-step obstacles that create a conflict between body stability (attenuating deviations in body motion) and consistent leg force–length dynamics (for economy and leg safety). We also test the hypothesis that control priorities shift between body stability and leg safety with increasing body size, reflecting use of active control to overcome size-related challenges. Weight-support demands lead to a shift towards straighter legs and stiffer steady gait with increasing body size, but it remains unknown whether non-steady locomotor priorities diverge with size. We found that all measured species used a consistent obstacle negotiation strategy, involving unsteady body dynamics to minimise fluctuations in leg posture and loading across multiple steps, not directly prioritising body stability. Peak leg forces remained remarkably consistent across obstacle terrain, within 0.35 body weights of level running for obstacle heights from 0.1 to 0.5 times leg length. All species used similar stance leg actuation patterns, involving asymmetric force–length trajectories and posture-dependent actuation to add or remove energy depending on landing conditions. We present a simple stance leg model that explains key features of avian bipedal locomotion, and suggests economy as a key priority on both level and uneven terrain. We suggest that running ground birds target the closely coupled priorities of economy and leg safety as the direct imperatives of control, with adequate stability achieved through appropriately tuned intrinsic dynamics

Particle-identification capability of the straw tube tracker and feasibility studies for the charmed-baryon program with PANDA

PANDA zal een van de belangrijkste experimenten zijn bij de toekomstige Faciliteit voor Antiproton en Ion Onderzoek (FAIR), welke in aanbouw is in Darmstadt, Duitsland. Het PANDA experiment zal botsingen onderzoeken tussen een straal van antiprotonen en een gefixeerd proton of nucleair doelwit. PANDA heeft een unieke opstelling vergeleken met andere natuurkunde experimenten en zal een unieke toegang geven tot verschillende natuurkunde onderwerpen. De verwachting is dat het PANDA experiment zal voorzien in nieuwe resultaten die helpen de zware-baryon sector experimenteel in kaart te brengen. Het Λc baryon speelt een significante rol in het begrijpen van zowel charm als bottom baryonen. PANDA bestaat uit subdetectoren die geoptimaliseerde individuele taken hebben. Een van de belangrijke taken is de reconstructie van de afgelegde baan, die gebaseerd is op informatie verkregen van de baandetectoren. PANDA heeft vier belangrijke baandetectoren en een daarvan is de Straw Tube Tracker (STT), een cilindrische detector die bestaat uit met gas gevulde buizen. Dit proefschrift presenteert Monte Carlo (MC) -simulaties die zijn uitgevoerd om het vermogen van PANDA bij gecharmeerde baryonproductie te onderzoeken. Daarnaast worden de resultaten gepresenteerd van tests die zijn uitgevoerd met een prototype STT-detector onderzoek ook de elektronische uitlezing en tracking en PID-prestaties om eindelijk een beslissing te nemen om de PANDA STT-detector te lezen

The Trend of Hydatidosis in Kermanshah Province, Western Iran (1986–2008)

Background: Hydatidosis is the larval stage of the Echinococcus granulosus. This disease is en­demic in Iran. There are many studies about hydatidosis in different regions of the country, but there is not any information about the disease in Kermanshah Province. This article will review all available data about hydatidosis in this province.Methods: Using web based search engines and a survey on medical student's theses, all the informa­tion about hydatid cysts in the province from 1986 -2008 was collected.Results: During these twenty years, at least 482 proven cases of hydatid cyst have been identified in the province. Accordingly, the trend of hydatid cyst operation in the province has been grow­ing and the average annual number of cases has reached 1.41/100,000. Frequency of disease in urban areas was slightly higher than rural areas and the rate of infection in housewives was more than others.Conclusion: Because of the growing trend of hydatid cyst operation in Kermanshah Province, which may be due to many different reasons, this province should be considered as one of the impor­tant endemic regions of hydatidosis in Iran