Grasping and releasing agarose micro beads in water drops

The micromanipulation of micro objects is nowadays the focus of several investigations, specially in biomedical applications. Therefore, some manipulation tasks are required to be in aqueous environment and become more challenging because they depend upon observation and actuation methods that are compatible with MEMS Technology based micromanipulators. This paper describes how three grasping-releasing based tasks have been successfully applied to agarose micro beads whose average size is about 60 \u3bcm: (i) the extraction of a single micro bead from a water drop; (ii) the insertion of a single micro bead into the drop; (iii) the grasping of a single micro bead inside the drop. The success of the performed tasks rely on the use of a microgripper previously designed, fabricated, and tested

IGF-1 and IGF-Binding Proteins and Bone Mass, Geometry, and Strength: Relation to Metabolic Control in Adolescent Girls With Type 1 Diabetes

Children and adolescents with poorly controlled type 1 diabetes mellitus (T1DM) are at risk for decreased bone mass. Growth hormone (GH) and its mediator, IGF-1, promote skeletal growth. Recent observations have suggested that children and adolescents with T1DM are at risk for decreased bone mineral acquisition. We examined the relationships between metabolic control, IGF-1 and its binding proteins (IGFBP-1, -3, -5), and bone mass in T1DM in adolescent girls 12–15 yr of age with T1DM (n = 11) and matched controls (n = 10). Subjects were admitted overnight and given a standardized diet. Periodic blood samples were obtained, and bone measurements were performed. Serum GH, IGFBP-1 and -5, glycosylated hemoglobin (HbA1c), glucose, and urine magnesium levels were higher and IGF-1 values were lower in T1DM compared with controls (p < 0.05). Whole body BMC/bone area (BA), femoral neck areal BMD (aBMD) and bone mineral apparent density (BMAD), and tibia cortical BMC were lower in T1DM (p < 0.05). Poor diabetes control predicted lower IGF-1 (r2 = 0.21) and greater IGFBP-1 (r2 = 0.39), IGFBP-5 (r2 = 0.38), and bone-specific alkaline phosphatase (BALP; r2 = 0.41, p < 0.05). Higher urine magnesium excretion predicted an overall shorter, lighter skeleton, and lower tibia cortical bone size, mineral, and density (r2 = 0.44–0.75, p < 0.05). In the T1DM cohort, earlier age at diagnosis was predictive of lower IGF-1, higher urine magnesium excretion, and lighter, thinner cortical bone (r2 ≥ 0.45, p < 0.01). We conclude that poor metabolic control alters the GH/IGF-1 axis, whereas greater urine magnesium excretion may reflect subtle changes in renal function and/or glucosuria leading to altered bone size and density in adolescent girls with T1DM

Establishment and cryptic transmission of Zika virus in Brazil and the Americas

Transmission of Zika virus (ZIKV) in the Americas was first confirmed in May 2015 in northeast Brazil1. Brazil has had the highest number of reported ZIKV cases worldwide (more than 200,000 by 24 December 20162) and the most cases associated with microcephaly and other birth defects (2,366 confirmed by 31 December 20162). Since the initial detection of ZIKV in Brazil, more than 45 countries in the Americas have reported local ZIKV transmission, with 24 of these reporting severe ZIKV-associated disease3. However, the origin and epidemic history of ZIKV in Brazil and the Americas remain poorly understood, despite the value of this information for interpreting observed trends in reported microcephaly. Here we address this issue by generating 54 complete or partial ZIKV genomes, mostly from Brazil, and reporting data generated by a mobile genomics laboratory that travelled across northeast Brazil in 2016. One sequence represents the earliest confirmed ZIKV infection in Brazil. Analyses of viral genomes with ecological and epidemiological data yield an estimate that ZIKV was present in northeast Brazil by February 2014 and is likely to have disseminated from there, nationally and internationally, before the first detection of ZIKV in the Americas. Estimated dates for the international spread of ZIKV from Brazil indicate the duration of pre-detection cryptic transmission in recipient regions. The role of northeast Brazil in the establishment of ZIKV in the Americas is further supported by geographic analysis of ZIKV transmission potential and by estimates of the basic reproduction number of the virus

Direct Coupling of Robotic Hands or Prostheses with the Radius Ulna Complex

A new method of mechanically connecting artificial or robotic hands to the human arm is herein described. The idea is based on techniques which make use of fracture fixation devices, very well known in orthopedics. The presented connecting system consists in a real 3 DOF (w.r.t. the humerus) mechanism that has two end plates which are fixed directly, one on the radius, on the ulna the other. Since the system is a new concept project, no data exists about its reliability. Therefore, in the paper, a feasibility study on the most delicate components is described. In particular, FEA has been performed on the screws and on the bone-nut-screws, and some experimental tests in vitro have been made on a pig rib

A Comprehensive Evaluation of the Efficiency of an Integrated Biogas, Trigen and Greenhouse Plant, using Digraph Theory

This paper describes how directed graphs (digraphs) have been used for evaluating the total efficiency of a complex Plant that has been designed for the combined production of food, heat, cooling, and electrical energy. This task required three basic activities. Firstly, the overall plant scheme was studied in detail in order to identify the elementary blocks, each one having its own efficiency value. Each block corresponded to a single node of the digraph. Secondly, the system had to be considered as a whole. The development of the global scheme required the identification of all the directed arcs that were corresponding to the energy flows. Finally, a new algorithm for the evaluation of the overall efficiency was applied to the resultant digraph. This method allowed us to obtain the solution in algebraic symbolic form, automatically, provided that the digraph arc list was supplied to the developed PC code, together with the flow repartitions. The algorithm is quite robust and could also be used in systems with flow recirculation

A new NEMS Based Linear-to-Rotary Displacement-Capacity Transducer

This paper presents a new NEMS-Technology based device, which transduces micro-metric linear displacements of a tip probe into capacity variations of a rotary comb-drive. The mechanical structure of this device is obtained through three basic steps. Firstly, the pseudo-rigid body equivalent mechanism (PRBM) is obtained by optimizing a straight-line path generator (D-gauge mechanism). Then, the PRBM is transformed into a compliant structure by replacing revolute joints with flexure hinges and by adding a differential comb-drive sensible to variation capacity. Finally, the geometry is transferred to the device by means of a process based on electron beam lithography