Performance test and verification of an off‐the‐shelf automated avian radar tracking system

Microwave radar is an important tool for observation of birds in flight and represents a tremendous increase in observation capability in terms of amount of surveillance space that can be covered at relatively low cost. Based on off‐the‐shelf radar hardware, automated radar tracking systems have been developed for monitoring avian movements. However, radar used as an observation instrument in biological research has its limitations that are important to be aware of when analyzing recorded radar data. This article describes a method for exploring the detection capabilities of a dedicated short‐range avian radar system used inside the operational Smøla wind‐power plant. The purpose of the testing described was to find the maximum detection range for various sized birds, while controlling for the effects of flight tortuosity, flight orientation relative to the radar and ground clutter. The method was to use a dedicated test target in form of a remotely controlled unmanned aerial vehicle (UAV) with calibrated radar cross section (RCS), which enabled the design of virtually any test flight pattern within the area of interest. The UAV had a detection probability of 0.5 within a range of 2,340 m from the radar. The detection performance obtained by the RCS ‐calibrated test target (?11 dBm², 0.08 m² RCS ) was then extrapolated to find the corresponding performance of differently sized birds. Detection range depends on system sensitivity, the environment within which the radar is placed and the spatial distribution of birds. The avian radar under study enables continuous monitoring of bird activity within a maximum range up to 2 km dependent on the size of the birds in question. While small bird species may be detected up to 0.5–1 km, larger species may be detected up to 1.5–2 km distance from the radar.     

Food Intake Recruits Orosensory and Post-ingestive Dopaminergic Circuits to Affect Eating Desire in Humans

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Gastric effects and side effects of synthetic secretin in man

The gastric effects of synthetic secretin given in a depot reparation as subcutaneous injection or in different doses as intravenous infusion were studied in 10 healthy volunteers. Peptone-stimulated gastric acid secretion and serum gastrin were significantly suppressed with a clear dose-response inhibition of acid output. There was a significant correlation between percentage inhibition of acid secretion and plasma secretin concentrations which were greatly above those seen physiologically. Serum lipase and trypsin increased significantly. Most subjects lost fluid from diuresis and diarrhoea, so that serum sodium and total protein concentrations also increased significantly. These side effects cast doubt on the clinical value of prolonged infusions of pharmacological doses of synthetic secretion in critically ill patients.     

Serum Lp(a) lipoprotein concentrations in insulin dependent diabetic patients with microalbuminuria.

OBJECTIVE--To compare the serum concentrations of lipoproteins and apolipoproteins in insulin dependent diabetic patients with and without microalbuminuria. DESIGN--Cross sectional study. SETTING--Paediatric and medical outpatient clinic at a university hospital. PATIENTS--76 insulin dependent diabetic patients: 41 with microalbuminuria (20 males, 21 females) and 35 controls without microalbuminuria (18 males, 17 females). The two groups were similar with respect to age, duration of disease, and haemoglobin A1c concentrations before the study. MAIN OUTCOME MEASURES--Serum concentrations of Lp(a) lipoprotein, total cholesterol, high density lipoprotein cholesterol, very low density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides, and apolipoproteins A-I, A-II, and B. RESULTS--Median serum Lp(a) lipoprotein concentration was 10.0 mg/100 ml in the microalbuminuric group and 4.9 mg/100 ml in the control group (p = 0.007). 17 (41%) of the microalbuminuric patients and five (14%) of the control patients had Lp(a) lipoprotein values above the upper quartile of a normal population. Median serum triglycerides concentrations in the microalbuminuric and control groups were 1.15 mmol/l and 0.88 mmol/l respectively (p = 0.03). Median very low density lipoprotein cholesterol concentration was 0.52 mmol/l in the microalbuminuric group and 0.40 mmol/l in the control group (p = 0.03). No significant differences in serum concentrations of total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, or apolipoproteins A-I, A-II, and B were found between the groups. CONCLUSIONS--Serum concentrations of Lp(a) lipoprotein are twice as high in insulin dependent diabetic patients with microalbuminuria as in those without microalbuminuria. Increased concentrations of Lp(a) lipoprotein might partly explain the increased morbidity and mortality from cardiovascular disease observed among patients with diabetic nephropathy.     

Recovery of 6-pentyl-alpha-pyrone fromTrichoderma viride culture medium by perevaporation

Summary Cultivation ofTrichoderma viride yields the volatile lactone 6-pentyl-alpha-pyrone (6-PP) as principal metabolite in concentration of up to 1 g/l. Separation and enrichment of 6-PP from the culture medium is effected by pervaporation through hydrophobic membranes. Virtually complete removal of 6-PP from inactive culture medium is achieved by batch pervaporation. Unlike steam distillation, pervaporation may be directly coupled to the active fermenter.     

Action of intragastric ethanol on pancreatic exocrine secretion in relation to the interdigestive gastrointestinal motility in humans

On different days, fasted volunteers were given either 100 ml of ethanol (40% v/v), glucose (isocaloric to ethanol) or distilled water intragastrically; the instillations always starting during the first observed duodenal phase I of the interdigestive migrating complex (IMC). Both ethanol and glucose produced a fed pattern of motility but only glucose significantly (P less than 0.05) delayed the reappearance of a new duodenal phase III of the IMC when compared to water. Ethanol and glucose significantly increased the 1-h duodenal bicarbonate output 7- and 16-fold, respectively. Glucose, but not ethanol, stimulated the duodenal amylase output when compared to water. Glucose, but not ethanol, caused a significant rise in plasma gastrin concentration; plasma secretin levels not being altered by both substances. We conclude that in non-alcoholic humans, an intragastric administration of ethanol in a concentration present in whisky and in an amount that is consumed in ordinary social drinking has a weak stimulatory action on pancreatic bicarbonate secretion and that this action is not mediated by release of secretin.     

Protein refolding in peroxisomes is dependent upon an HSF1-regulated function

Post-heat shock refolding of luciferase requires chaperones. Expression of a dominant negative HSF1 mutant (dnHSF1), which among other effects depletes cells of HSF1-regulated chaperones, blocked post-heat shock refolding of luciferase targeted to the cytoplasm, nucleus, or peroxisomes, while refolding of endoplasmic reticulum (ER)-targeted luciferase was inhibited by about 50 %. Luciferase refolding in the cytoplasm could be partially restored by expression of HSPA1A and fully by both HSPA1A and DNAJB1. For full refolding of ER luciferase, HSPA1A expression sufficed. Neither nuclear nor peroxisomal refolding was rescued by HSPA1A. A stimulatory effect of DNAJB1 on post-heat shock peroxisomal luciferase refolding was seen in control cells, while refolding in the cytoplasm or nucleus in control cells was inhibited by DNAJB1 expression in the absence of added HSPA1A. HSPB1 also improved refolding of peroxisomal luciferase in control cells, but not in dnHSF1 expressing cells. HSP90, HSPA5, HSPA6, and phosphomevalonate kinase (of which the synthesis is also downregulated by dnHSF1) had no effect on peroxisomal refolding in either control or chaperone-depleted cells. The chaperone requirement for post-heat shock refolding of peroxisomal luciferase in control cells is thus unusual in that it can be augmented by DNAJB1 or HSPB1 but not by HSPA1A; in dnHSF1 expressing cells, expression of none of the (co)-chaperones tested was effective, and an as yet to be identified, HSF1-regulated function is required.     

Differential investment and costs during avian incubation determined by individual quality: an experimental study of the common eider (Somateria mollissima)

Individuals of different quality may have different investment strategies, shaping responses to experimental manipulations, thereby rendering the detection of such patterns difficult. However, previous clutch-size manipulation studies have infrequently incorporated individual differences in quality. To examine costs of incubation and reproductive investment in relation to changes in clutch size, we enlarged and reduced natural clutch sizes of four and five eggs by one egg early in the incubation period in female common eiders (Somateria mollissima), a sea duck with an anorectic incubation period. Females that had produced four eggs (lower quality) responded to clutch reductions by deserting the nest more frequently but did not increase incubation effort in response to clutch enlargement, at the cost of reduced hatch success of eggs. Among birds with an original clutch size of five (higher quality), reducing and enlarging clutch size reduced and increased relative body mass loss respectively without affecting hatch success. In common eiders many females abandon their own ducklings to the care of other females. Enlarging five-egg clutches led to increased brood care rate despite the higher effort spent incubating these clutches, indicating that the higher fitness value of a large brood is increasing adult brood investment. This study shows that the ability to respond to clutch-size manipulations depends on original clutch size, reflecting differences in female quality. Females of low quality were reluctant to increase investment at the cost of lower hatch success, whereas females of higher quality apparently have a larger capacity both to increase incubation effort and brood care investment.