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Modeling and control of a novel heat exchange reactor, the Open Plate Reactor

A new chemical reactor, the Open Plate Reactor, is being developed by Alfa Laval AB. It combines good mixing with high heat transfer capacity into one operation. With the new concept, highly exothermic reactions can be produced using more concentrated reactants. A nonlinear model of the reactor is derived and a control system is developed. For temperature control a cooling system is designed and e

Balance Control and Adaptation during Vibratory Perturbations in Middle-Aged and Elderly Humans.

The objective was to investigate if healthy elderly people respond and adapt differently to postural disturbances compared to middle-aged people. Thirty middle-aged (mean age 37.8 years, range 24–56 years) and forty healthy elderly subjects (mean age 74.6 years, range 66–88 years) were tested with posturography. Body sway was evoked by applying pseudorandom vibratory stimulation to the belly of th

Rapid early-Holocene environmental changes in northern Sweden based on studies of two varved lake-sediment sequences

Mineral magnetic, organic carbon and pollen studies of two varved Holocene lake-sediment sequences in the boreal forest of northern Sweden indicate that significant environmental changes took place between c. 6000 and 5700 BC. This interval is characterized by an increase in mineral-matter accumulation, which is a proxy for winter-snow accumulation, and a statistically significant decrease in tota

Cardiac Structure and Function Before and After Parathyroidectomy in Patients With Asymptomatic Primary Hyperparathyroidism

Background: Primary hyperparathyroidism (PHPT) is associated with cardiac disease and increased risk of all-cause and cardiovascular mortality. We investigated cardiac structural and functional parameters before and after successful parathyroidectomy in asymptomatic PHPT patients. Methods and Results: Forty-nine PHPT patients (age: 62.9 +/- 11 years, 5 men) and 48 healthy control subjects, matched

Double-strand break DNA repair genotype predictive of later mortality and cancer incidence in a cohort of non-smokers

We followed-up for mortality and cancer incidence 1088 healthy non-smokers from a population-based study, who were characterized for 22 variants in 16 genes involved in DNA repair pathways. Follow-up was 100% complete. The association between polymorphism and mortality or cancer incidence was analyzed using Cox Proportional Hazard regression models. Ninety-five subjects had died in a median follow

Migration speed and scheduling of annual events by migrating birds in relation to climate change

Empirical evidence for changed timing of migration in birds is emerging from both American and Euro-African migration systems. These changes are usually interpreted as a consequence of changes in climate. Responses in timing of migration and breeding may differ among species, and the adaptive significance is not well understood. There is a lack of theoretical understanding about time-shifts in lif

Cerebral Inflammatory Response after Fetal Asphyxia and Hyperoxic Resuscitation in Newborn Sheep.

Resuscitation with pure oxygen at birth after fetal asphyxia may aggravate brain damage by inducing pro-inflammation. The toll-like receptors (TLRs) may serve a pro-inflammatory role in hyperoxemia during ischemia-reperfusion. Sixteen near-term fetal sheep (132-136 d) were subjected to 10 min of cord occlusion, delivery and mechanical ventilation with 100% O-2 (n = 8), or 21% O-2 (n = 8) for 30 mi

Racemic, S(+)- and R(-)-ketamine do not increase elevated intracranial pressure

Background: There is controversy regarding the influence of ketamine and its enantiomers on cerebral haemodynamics at increased intracranial pressure (ICP). This study was designed to compare cerebrovascular responses, with particular respect to ICP, to bolus injections of racemic, S(+)- and R(-)-ketamine in an experimental model of intracranial hypertension. Methods: Nine pigs were anaesthetised

Monitor – Biology

The hottest developments in the fields of cancer research, neuroscience, genomics and proteomics, anti-virals and more, with a pick of the key research papers in these areas.

Compaction of DNA by gemini surfactants: Effects of surfactant architecture

The interaction between bacteriophage T4 DNA and cationic gemini surfactants was studied by the use of fluorescence microscopy. Upon addition of surfactant, DNA undergoes a transition from random coil to globule, with an intermediate coexistence region. The state behavior of a DNA-gemini surfactant system was found to depend on spacer length, valency, head group size, and tail length. A series of

The effect of dominance rank on fat deposition and food hoarding in the Willow Tit Parus montanus - an experimental test

We studied the effects of dominance rank on fat deposition and hoarding behaviour in Willow Tits Parus montanus . Dominant individuals can displace subordinates which gives them priority to new food sources; they can also pilfer stored food from subordinates. This gives subordinates less certain access than dominants both to their own caches and to new food sources. Theory predicts that subordinat

Monitor – Biology

An insight into the latest developments in drug discovery through brief synopses of recent publications, summarizing the chemistry, pharmacological significance and biological relevance of new molecules.

Fracture mechanics in timber engineering - Strength analyses of components and joints

Traditional timber engineering design approaches use for simple geometries stress- or strain-based criteria for strength analyses. For more complex cases purely empirical methods are also used. Although practical, purely empirical methods are not general, and could lead to estimations on the unsafe side, if extrapolated outside their original scope. It is furthermore known that stress- or strain-b

Soluble adhesion molecules and angiotensin-converting enzyme in dementia.

We aimed to determine plasma and cerebrospinal fluid (CSF) levels of angiotensin-converting enzyme (ACE) and the soluble forms of intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1) and platelet endothelial cell adhesion molecule-1 (sPECAM-1) as surrogate markers for endothelial cell activation in clinically diagnosed patients with Alzheimer's disease (AD, n=26

Risk of lymphoma and leukaemia after bacille Calmette-Guerin and smallpox vaccination: A Danish case-cohort study

Vaccines may have non-specific effects as suggested mainly in mortality studies from low-income countries. The objective was to examine the effects of BCG and smallpox vaccinations on subsequent risk of lymphoma and leukaemia in a Danish population experiencing rapid out-phasing of these vaccines. In a background cohort (N=47,622) from the Copenhagen School Health Records Register, cases of leukae

Exhaled and nasal NO levels in allergic rhinitis: relation to sensitization, pollen season and bronchial hyperresponsiveness

Exhaled nitric oxide is a potential marker of lower airway inflammation. Allergic rhinitis is associated with asthma and bronchial hyperresponsiveness. To determine whether or not nasal and exhaled NO concentrations are increased in allergic rhinitis and to assess the relation between hyperresponsiveness and exhaled NO, 46 rhinitic and 12 control subjects, all nonasthmatic nonsmokers without upper

Oral function test for monitoring suction and swallowing in the neurologic patient

Disturbances in swallowing are common in neurologic disease but difficult to evaluate in the clinical setting. Fundamental variables such as bolus volume, swallow capacity (volume ingested over time), and the relation between ingestion and time for important events in oral and pharyngeal swallowing have not been sufficiently studied. We therefore employed a composite method for monitoring oral and

Horizontal flight of a swallow (Hirundo rustica) observed in a wind tunnel, with a new method for directly measuring mechanical power

A swallow flying in the Lund wind tunnel was observed from the side and from behind, by two synchronised highspeed video cameras. The side-view camera provided a record of the vertical position of a white mark, applied to the feathers behind and below the eye, from which the vertical acceleration was obtained. The rear-view camera provided measurements of the mean angle of the left and right humer