Micellar Aggregates of Gemini Surfactants: Monte Carlo Simulation of a Microscopic Model

We propose a "microscopic" model of gemini surfactants in aqueous solution. Carrying out extensive Monte Carlo simulations, we study the variation of the critical micellar concentration (CMC) of these model gemini surfactants with the variation of the (a) length of the spacer connecting the two hydrophilic heads, (b) length of the hydrophobic tail and (c) the bending rigidity of the hydrocarbon chains forming the spacer and the tail; some of the trends of variation are counter-intuitive but are in excellent agreement with the available experimental results. Our simulations also elucidate the dependence of the shapes of the micellar aggregates and the magnitude of the CMC on the geometrical shape and size of the surfactant molecules and the electrical charge on the hydrophilic heads

Vertebral artery dissection presenting as a Brown-Séquard syndrome: a case report

<p>Abstract</p> <p>Introduction</p> <p>Vertebral artery dissection has become increasingly recognized as an important cause of stroke. It usually presents with posterior headache or neck pain followed within hours or days by signs of posterior circulation stroke. To the best of our knowledge, the clinical presentation of a Brown-Séquard syndrome with a vertebral artery dissection has been reported only once before.</p> <p>Case presentation</p> <p>An otherwise healthy 35-year-old man presented with acute left-sided weakness. He had experienced left-sided posterior neck pain after a 4-hour flight 4 weeks previously. Physical examination was consistent with a left Brown-Séquard syndrome. Magnetic resonance angiography showed evidence of left vertebral artery dissection. He improved after therapy with anticoagulants.</p> <p>Conclusion</p> <p>We report a case of an unusual presentation of a relatively uncommon condition. This diagnosis should be considered early in relatively young patients with stroke-like symptoms or unexplained neck pain, because missing a dissection can result in adverse outcomes.</p

Congenital dislocation of the hip: Optimal screening strategies in 2014

AbstractA prospective multi-centre nationwide study of patients with congenital dislocation of the hip (CDH) diagnosed after 3 months of age was conducted with support from the French Society for Paediatric Orthopaedics (Société Française d’Orthopédie Pédiatrique [SoFOP]), French Organisation for Outpatient Paediatrics (Association Française de Pédiatrie Ambulatoire [AFPA]), and French-Speaking Society for Paediatric and Pre-Natal Imaging (Société Francophone d’Imagerie Pédiatrique et Prénatale [SFIPP]). The results showed inadequacies in clinical screening for CDH that were patent when assessed quantitatively and probably also present qualitatively. These findings indicate a need for a communication and educational campaign aimed at highlighting good clinical practice guidelines in the field of CDH screening. The usefulness of routine ultrasound screening has not been established. The findings from this study have been used by the authors and French National Health Authority (Haute Autorité de Santé [HAS]) to develop recommendations about CDH screening. There is an urgent need for a prospective randomised multi-centre nationwide study, which should involve primary-care physicians

BMQ

BMQ: Boston Medical Quarterly was published from 1950-1966 by the Boston University School of Medicine and the Massachusetts Memorial Hospitals

Vascular Abnormalities in the Neck Associated with Intracranial Aneurysms

ABSTRACT In 102 cases of ruptured intracranial aneurysms, the cervical as well as the cranial areas were explored by angiography. Loops in the course of the cervical vessels were present in 28 patients; features of fibromuscular dysplasia were present in 31 patients; and in 50 patients, no abnormalities were observed. In 7 patients, both cervical anomalies were present. Loops were associated with single aneurysms (95%), located primarily on the anterior communicating artery (76%), predominantly in men (M/F = 1.6). Aneurysms with fibromuscular dysplasia affected women more than men (F/M = 7), were frequently multiple (58%), and were located mainly on the intracranial part of the internal carotid and vertebral arteries (51%). These data suggest new concepts of aneurysm formation from inherited diseases and should permit the detection of some aneurysms before rupture

Fernerkennung als Mittel zur Bereitstellung von Planungsgrundlagen in der Dritten Welt : das Beispiel Sri Lanka

No abstract available