Statistical-learning method for predicting hydrodynamic drag, lift, and pitching torque on spheroidal particles.

A statistical learning approach is presented to predict the dependency of steady hydrodynamic interactions of thin oblate spheroidal particles on particle orientation and Reynolds number. The conventional empirical correlations that approximate such dependencies are replaced by a neural-network-based correlation which can provide accurate predictions for high-dimensional input spaces occurring in flows with nonspherical particles. By performing resolved simulations of steady uniform flow at 1≤Re≤120 around a 1:10 spheroidal body, a database consisting of Reynolds number- and orientation-dependent drag, lift, and pitching torque acting on the particle is collected. A multilayer perceptron is trained and validated with the generated database. The performance of the neural network is tested in a point-particle simulation of the buoyancy-driven motion of a 1:10 disk. Our statistical approach outperforms existing empirical correlations in terms of accuracy. The agreement between the numerical results and the experimental observations prove the potential of the method.

[Q fever: not just in sheep]. / Q-koorts: niet alleen bij schapen.

Four patients, a woman aged 41 years and 3 men aged 12, 47 and 44 years, developed high fever after returning from a farm vacation in the Ardèche (France). They also suffered from severe headache, a painful tightness of the chest, abdominal pain or myalgia. Other symptoms were shivers, tiredness and a cough. While physical examination revealed few abnormalities, the chest X-ray in 3 patients showed an atypical pneumonia. One of these patients developed dural venous sinus thrombosis with increased intraspinal pressure. This patient also showed signs of a slight hepatitis. Serological investigation revealed that all 4 patients were suffering from acute Q fever, a zoonosis caused by the Coxiella burnetii bacterium. All 4 had been present at lambing and sheep-shearing. The patients with pneumonia were treated with antibiotics. All 4 patients recovered well. It is known that animal birth products in particular can contain large numbers of bacteria and therefore be highly infectious.

[Acute and chronic Q fever; epidemiology, symptoms, diagnosis and therapy of infection caused by Coxiella burnetii]. / Acute en chronische Q-koorts; epidemiologie, symptomen, diagnostiek en therapie van infecties met Coxiella burnetii.

Q fever is a zoonosis caused by Coxiella burnetii, an obligate intracellular bacterium. Domestic ungulates and parturient cats are the primary reservoirs of infection. The animals excrete the bacterium in urine, faeces, milk and amniotic fluid. After desiccation the micro-organism spreads via aerosols. After inhalation or ingestion and an incubation period of 2-6 weeks acute Q fever may develop with atypical pneumonia and hepatitis as major clinical symptoms. The infection also may present as a flu-like illness or remain asymptomatic. Generally, the prognosis is favourable. However, endocarditis or another chronic form of Q fever occasionally develops with possibly fatal outcome. Diagnosis relies upon serologic testing with an indirect immunofluorescence method. Doxycycline is the antibiotic of choice in the treatment of Q fever. Endocarditis needs therapy for years with the addition of rifampin or hydroxychloroquine. Q fever is poorly recognised due to the variety of clinical presentations.

Neuroendoscopic third ventriculostomy: a nursing perspective.

Endoscopic third ventriculostomy is an old technique that has gained greater acceptance in recent years with the advent of new endoscopic technology. This procedure, which involves fenestrating the floor of the third ventricle to communicate the basilar cisterns with the third ventricle offers new hope to patients with non-communicating hydrocephalus. Until recently, the only accepted treatment for these patients was the placement of a ventriculoperitoneal shunt to drain the accumulating cerebrospinal fluid. It is well known that shunting carries the risks of infection, blockage and overdrainage. This technique provides an alternative to a less than perfect treatment for reestablishing CSF pathways. Patients best suited for the procedure have delayed onset aqueductal stenosis caused by a tumor, cyst or hemorrhagic event. Patients with aqueductal stenosis as a consequence of myelomeningeocele fare less well, but show better success with the technique if it is performed as a follow-up to shunting rather than as an initial procedure. Several techniques may be used to perform third ventriculostomy. An understanding of the special needs of the patient undergoing the procedure is essential to optimum care.

The development of PdNi thermoseeds for interstitial hyperthermia.

Magnetic induction heating of thermoseed implants can be used to produce highly localized hyperthermia in deep-seated tumors. Automatic temperature control throughout the tumor can be achieved by the self-regulating character of ferromagnetic seeds, which corrects for local variations in heat loss due to blood perfusion. An increased sharpness of the ferromagnetic transition at the Curie temperature, Tc, improves the performance of self-regulating control. This was realized for palladium-nickel alloys by a "cold working" procedure preceded and followed by annealing. Palladium-nickel seeds with a predetermined Tc were produced, showing a sharp decrease at Tc of the magnetic susceptibility and the heat production.

Sonographic detection of early gallbladder cancer.

During routine abdominal sonography and in cases of 'normal' gallbladder symptomatology, the sonographer may encounter an unsuspected early gallbladder cancer. 1 case report is presented in which a patient previously known with gallbladder concrements developed a primary gallbladder carcinoma within a period of 1 1/2 years. The clinical, pathological and prognostic features are discussed.