Characteristic spatial scale of vesicle pair interactions in a plane linear flow

We report the experimental studies on interaction of two vesicles trapped in a microfluidic analog of four-roll mill, where a plane linear flow is realized. We found that the dynamics of a single vesicle is significantly altered by the presence of another vesicle at separation distances up to about 3.2 \div 3.7 times of effective radius of the vesicles. This is supported by direct measurements of a single vesicle back-reaction on the velocity field. Thus, the experiment provides the lower bound for the interaction scale of vesicles and so the corresponding upper bound for the volume fraction \phi=0.08 \div 0.13 of non-interacting vesicle suspensions.Comment: 5 pages, 8 figures, PRE accepted for publicatio

Modeling of Rolling-Piston Compressors with Special Attention to the Suction and Discharge Processes

The present paper describes a simulation model developed to predict the performance of rolling-piston compressors with special attention to the suction and discharge processes. The relevant input data required by the model, such as clearances between moving parts, valve stiffness and natural frequency and electric motor efficiency, were obtained experimentally. Correlations for effective flow and force areas associated with the suction and discharge processes were derived from flow simulations. It was found that the position of the rolling piston in relation to the suction and discharge ports must be included to fully characterize the effective flow and force areas. Numerical predictions of the thermodynamic inefficiencies associated with a R22 rolling-piston compressor were compared with measurements and good agreement was found at different operating conditions

The Little Book of Public Space and the Internet of Things

Our public spaces are changing, they are at the forefront of a technological revolution yet this is a revolution that often remains hidden from sight. Sensors are being installed and the ability to interact with objects in our spaces – from projects such as the PETRAS Talking Trees through to conversations with Lamp Posts or data interactions with local wildlife is changing our interactions both in and with these places and spaces. This Little Book explores safety and security and moves onto maintenance. We then look at some of the issues affecting people and explore health, community building and culture while exploring the use of public space for play. After this, we explore conservation and culture, transport and signage, accessibility and then, finally, we discuss future trends

High-speed FPGA 10's complement adders-subtractors

This paper first presents a study on the classical BCD adders from which a carry-chain type adder is redesigned to fit within the Xilinx FPGA's platforms. Some new concepts are presented to compute the P and G functions for carry-chain optimization purposes. Several alternative designs are presented. Then, attention is given to FPGA implementations of add/subtract algorithms for 10's complement BCD numbers. Carry-chain type circuits have been designed on 4-input LUTs (Virtex-4, Spartan-3) and 6-input LUTs (Virtex-5) Xilinx FPGA platforms. All designs are presented with the corresponding time performance and area consumption figures. Results have been compared to straight implementations of a decimal ripple-carry adder and an FPGA 2's complement binary adder-subtractor using the dedicated carry logic, both carried out on the same platform. Better time delays have been registered for decimal numbers within the same range of operands.This work is supported by the Universities FASTA, Mar del Plata, Argentina, UNCPBA Tandil, Argentina, UAM ,Madrid, Spain, and URV, Tarragona, Spain; it has been partially granted by the CICYT of Spain under contract TEC2007- 68074-C02-02/MIC

Is unicompartmental-to-unicompartmental revision knee arthroplasty a reliable option? Case-control study

AbstractBackgroundIn selected patients with failed unicompartmental knee arthroplasty (UKA), revision UKA is a reliable option and may even provide lower morbidity rates and better functional outcomes compared to revision total knee arthroplasty.Material and methodsIn a multicentre retrospective study of 425 knees requiring revision surgery after UKA, 36 knees were managed with revision UKA.ResultsOf the 36 knees, 3 (8.33%) required iterative revision surgery, for aseptic loosening. After a mean follow-up of 8.3 years, the mean IKS knee and function scores were high (93.81/100 and 90.77/100, respectively).DiscussionIn carefully selected patients, UKA-to-UKA revision performed according to a rigorous operative technique deserves a role in the surgical strategy for failed UKA.Level of evidenceIII, multicentre retrospective case-control study

Whole-head recording of chemosensory activity in the marine annelid Platynereis dumerilii

This is the final version. Available on open access from the Royal Society via the DOI in this recordData accessibility: The datasets supporting the conclusions of this article, as well as videos showing examples of calcium activity, have been provided as the electronic supplementary material. Raw calcium recordings are available on demand.Chemical detection is key to various behaviours in both marine and terrestrial animals. Marine species, though highly diverse, have been underrepresented so far in studies on chemosensory systems, and our knowledge mostly concerns the detection of airborne cues. A broader comparative approach is therefore desirable. Marine annelid worms with their rich behavioural repertoire represent attractive models for chemosensation. Here, we study the marine worm Platynereis dumerilii to provide the first comprehensive investigation of head chemosensory organ physiology in an annelid. By combining microfluidics and calcium imaging, we record neuronal activity in the entire head of early juveniles upon chemical stimulation. We find that Platynereis uses four types of organs to detect stimuli such as alcohols, esters, amino acids and sugars. Antennae are the main chemosensory organs, compared to the more differentially responding nuchal organs or palps. We report chemically evoked activity in possible downstream brain regions including the mushroom bodies (MBs), which are anatomically and molecularly similar to insect MBs. We conclude that chemosensation is a major sensory modality for marine annelids and propose early Platynereis juveniles as a model to study annelid chemosensory systems.FP7 Marie Curie Initial Training NetworkEuropean Molecular Biology LaboratoryDeutsche Forschungsgemeinschaf

Differential Hox expression in murine embryonic stem cell models of normal and malignant hematopoiesis

The Hox family are master transcriptional regulators of developmental processes, including hematopoiesis. The Hox regulators, caudal homeobox factors (Cdx1-4), and Meis1, along with several individual Hox proteins, are implicated in stem cell expansion during embryonic development, with gene dosage playing a significant role in the overall function of the integrated Hox network. To investigate the role of this network in normal and aberrant, early hematopoiesis, we employed an in vitro embryonic stem cell differentiation system, which recapitulates mouse developmental hematopoiesis. Expression profiles of Hox, Pbx1, and Meis1 genes were quantified at distinct stages during the hematopoietic differentiation process and compared with the effects of expressing the leukemic oncogene Tel/PDGFR;2. During normal differentiation the Hoxa cluster, Pbx1 and Meis1 predominated, with a marked reduction in the majority of Hox genes (27/39) and Meis1 occurring during hematopoietic commitment. Only the posterior Hoxa cluster genes (a9, a10, a11, and a13) maintained or increased expression at the hematopoietic colony stage. Cdx4, Meis1, and a subset of Hox genes, including a7 and a9, were differentially expressed after short-term oncogenic (Tel/PDGFR;2) induction. Whereas Hoxa4-10, b1, b2, b4, and b9 were upregulated during oncogenic driven myelomonocytic differentiation. Heterodimers between Hoxa7/Hoxa9, Meis1, and Pbx have previously been implicated in regulating target genes involved in hematopoietic stem cell (HSC) expansion and leukemic progression. These results provide direct evidence that transcriptional flux through the Hox network occurs at very early stages during hematopoietic differentiation and validates embryonic stem cell models for gaining insights into the genetic regulation of normal and malignant hematopoiesis

Precipitation kinetics analysis of oxide dispersion strengthened steels for their application as cladding material in Gen.IV power plants

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