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Actuator disk model and span efficiency of flapping flight in bats based on time-resolved PIV measurements

All animals flap their wings in powered flight to provide both lift and thrust, yet few human-engineered designs do so. When combined with flexible wing surfaces, the resulting unsteady fluid flows and interactions in flapping flight can be complex to describe, understand, and model. Here, a simple modified actuator disk is used in a quasi-steady description of the net aerodynamic lift forces on s

Time-resolved (kHz) 3D imaging of OH PLIF in a flame

Based on scanning planar laser-induced fluorescence of OH, a measurement system with the capability to record time-resolved three-dimensional image sequences of the OH concentration and the flame front is demonstrated on a premixed flame. A dual-mirror scanning system is used to obtain equidistance between the illuminated planes. Non-uniformities in the laser sheet and laser absorption in the flam

Comparison between CARIBIC Aerosol Samples Analysed by Accelerator-Based Methods and Optical Particle Counter Measurements

Inter-comparison of results from two kinds of aerosol systems in the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on a Instrument Container) passenger aircraft based observatory, operating during intercontinental flights at 9-12 km altitude, is presented. Aerosol from the lowermost stratosphere (LMS), the extra-tropical upper troposphere (UT) and the tropical mid t

Software-based optimal PID design with robustness and noise sensitivity constraints

Even though PID control has been available for a long time, there are still no tuning methods including derivative action that have gained wide acceptance in industry. Also, there is still no general consensus for when one should use PID, PI or even I control on a process. The focus of this article is to present a new method for optimal PID control design that automatically picks the best controll

Evaluation of the optimal lengths and number of multiple windows for spectrogram estimation of SSVEP

The purpose of this paper is to present the optimal number of windows and window lengths using multiple window spectrogram for estimation of non-stationary processes with shorter or longer duration. Such processes could start in the EEG as a result of a stimuli, e.g. steady-state visual evoked potentials (SSVEP). In many applications the Welch method is used with standard set-ups for window length

Orientation and autumn migration routes of juvenile sharp-tailed sandpipers at a staging site in Alaska.

Arctic waders are well known for their impressive long-distance migrations between their high northerly breeding grounds and wintering areas in the Southern hemisphere. Performing such long migrations requires precise orientation mechanisms. We conducted orientation cage experiments with juvenile sharp-tailed sandpipers (Calidris acuminata) to investigate what cues they rely on when departing from

Stratum corneum molecular mobility in the presence of natural moisturizers.

The outermost layer of the skin, the stratum corneum (SC), is a lipid-protein membrane that experiences considerable osmotic stress from a dry and cold climate. The natural moisturizing factor (NMF) comprises small and polar substances, which like osmolytes can protect living systems from osmotic stress. NMF is commonly claimed to increase the water content in the SC and thereby protect the skin f

Fetal cerebral energy metabolism and electrocardiogram during experimental umbilical cord occlusion and resuscitation.

Objective. The purpose of this experimental study was to elucidate alterations in fetal energy metabolism in relation to ECG changes during extreme fetal asphyxia, postnatal resuscitation and the immediate post-resuscitatory phase. Study design. Five near-term fetal sheep were subjected to umbilical cord occlusion until cardiac arrest followed by delivery, resuscitation and postnatal pressure-cont

Accurate reaction energies in proteins obtained by combining QM/MM and large QM calculations

We here suggest and test a new method to obtain stable energies in proteins for charge-neutral reactions by running large quantum mechanical (QM) calculations on structures obtained by combined QM and molecular mechanics (QM/MM) geometry optimisation on several snapshots from molecular dynamics simulations. As a test case, we use a proton transfer between a metal-bound cysteine residue and a secon

Primary screening for human papillomavirus compared with cytology screening for cervical cancer in European settings: cost effectiveness analysis based on a Dutch microsimulation model

Objectives To investigate, using a Dutch model, whether and under what variables framed for other European countries screening for human papillomavirus (HPV) is preferred over cytology screening for cervical cancer, and to calculate the preferred number of examinations over a woman's lifetime. Design Cost effectiveness analysis based on a Dutch simulation model. Base case analyses investigated the

Genetics of coronary heart disease: towards causal mechanisms, novel drug targets and more personalized prevention.

Coronary heart disease (CHD) is an archetypical multifactorial disorder that is influenced by genetic susceptibility as well as both modifiable and nonmodifiable risk factors, and their interactions. Advances during recent years in the field of multifactorial genetics, in particular genomewide association studies (GWASs) and their meta-analyses, have provided the statistical power to identify and

Continuing Mobility and Occupational Participation Outside the Home in OldAge Is an Act of Negotiation

Facilitated by mobility, occupational participation outside the home is vital in old age. However, the relative importance of factors influencing mobility and occupational participation remains unclear. The present study describes older peoples’ motives for, and experiences of, mobility and occupational participation outside the home. Nine focus-group interviews were conducted and analyzed using c

Concurrent Isolation of Lymphocytes and Granulocytes Using Prefocused Free Flow Acoustophoresis

Microchip-based free flow acoustophoresis (FFA) in combination with two-dimensional cell prefocusing enables concurrent multiple target outlet fractionation of leukocytes into subpopulations (lymphocytes, monocytes, and granulocytes); we report on this method here. We also observed significantly increased accuracy in size-based fractionation of microbeads as compared to previously presented FFA mu

Improving methane production from wheat straw by digestate liquor recirculation in continuous stirred tank processes

Wheat straw is an abundant, cheap substrate that can be used for methane production. However, the nutrient content in straw is inadequate for methane fermentation. In this study, recycling digestate liquor was implemented in single-stage continuous stirred tank processes for enrichment of the nutrient content of straw with the aim of improving the methane production. The VS-based organic loading r

Further Insights into the Catalytical Properties of Deglycosylated Pyranose Dehydrogenase from Agaricus meleagris Recombinantly Expressed in Pichia pastoris

The present study focuses on fragmented deglycosylated pyranose dehydrogenase (fdgPDH) from Agaricus meleagris recombinantly expressed in Pichia pastoris. Fragmented deglycosylated PDH is formed from the deglycosylated enzyme (dgPDH) when it spontaneously loses a C-terminal fragment when stored in a buffer solution at 4 degrees C. The remaining larger fragment has a molecular weight of similar to

Novel disease-specific promoters for use in gene therapy for Parkinson's disease.

Gene therapy is a promising therapeutic tool for Parkinson's disease (PD), but there is a lack of evaluated cell specific promoters that are relevant for the disease. We have chosen PD relevant promoter candidates for gene therapy vectors based on either previous studies; Drd1a, Drd2 and pDyn, or from a microarray study on parkinsonian patients; ACE, DNAJC3, GALNS, MAP1a and RNF25. These candidate

Tunnel Field-Effect Transistors Based on InP-GaAs Heterostructure Nanowires.

We present tunneling field-effect transistors fabricated from InP-GaAs heterostructure nanowires with an n-i-p doping profile, where the intrinsic InP region is modulated by a top gate. The devices show an inverse subthreshold slope down to 50 mV/dec averaged over two decades with an on/off current ratio of approximately 10(7) for a gate voltage swing (V(GS)) of 1 V and an on-current of 2.2 μA/μm.