Distributed $k$ -Means Algorithm and Fuzzy $c$ -Means Algorithm for Sensor Networks Based on Multiagent Consensus Theory.

This paper is concerned with developing a distributed k-means algorithm and a distributed fuzzy c-means algorithm for wireless sensor networks (WSNs) where each node is equipped with sensors. The underlying topology of the WSN is supposed to be strongly connected. The consensus algorithm in multiagent consensus theory is utilized to exchange the measurement information of the sensors in WSN. To obtain a faster convergence speed as well as a higher possibility of having the global optimum, a distributed k-means++ algorithm is first proposed to find the initial centroids before executing the distributed k-means algorithm and the distributed fuzzy c-means algorithm. The proposed distributed k-means algorithm is capable of partitioning the data observed by the nodes into measure-dependent groups which have small in-group and large out-group distances, while the proposed distributed fuzzy c-means algorithm is capable of partitioning the data observed by the nodes into different measure-dependent groups with degrees of membership values ranging from 0 to 1. Simulation results show that the proposed distributed algorithms can achieve almost the same results as that given by the centralized clustering algorithms.

On the Bipartite Consensus for Generic Linear Multiagent Systems With Input Saturation.

The bipartite consensus problem for a group of homogeneous generic linear agents with input saturation under directed interaction topology is examined. It is established that if each agent is asymptotically null controllable with bounded controls and the interaction topology described by a signed digraph is structurally balanced and contains a spanning tree, then the semi-global bipartite consensus can be achieved for the linear multiagent system by a linear feedback controller with the control gain being designed via the low gain feedback technique. The convergence analysis of the proposed control strategy is performed by means of the Lyapunov method which can also specify the convergence rate. At last, the validity of the theoretical findings is demonstrated by two simulation examples.

Anterior corpus callosotomy combined with anterior temporal resection with amygdalohippocampectomy: outcome in a patient with congenital bilateral perisylvian syndrome.

Congenital bilateral perisylvian syndrome (CBPS) is characterized by epilepsy, cognitive deficits, pseudobulbar palsy and diplegia of the facial, pharyngeal and masticatory muscles. Epilepsy has been described in nearly 90% of affected patients. The epilepsy is usually severe and pharmacoresistant in about 55 percent of CBPS patients. Until now, only 12 cases of surgical treatment on CBPS have been reported; the surgical treatment is usually corpus callosotomy. In this paper, we describe a previously unreported combination of anterior corpus callosotomy plus anterior temporal lobectomy with amygdalohippocampectomy for a patient with CBPS, resulting in a satisfactory clinical outcome. Based on this case, we suggest that palliative focal resective surgery combined with anterior corpus callosotomy should be considered when a predominance of the epileptiform discharges suggests focal onset in patients with CBPS. Meanwhile, the clinical decision to adopt this combination surgery must be based on a thorough pre-surgical evaluation, and should take into account the clinical, radiological, and EEG features.

Prevalence of Candidatus Rickettsia tarasevichiae-Like Bacteria in Ixodid Ticks at 13 Sites on the Chinese-Russian Border.

To investigate the likely source population and candidate vectors of Candidatus Rickettsia tarasevichiae, the prevalence of this bacteria was quantified in specimens of four tick species that mainly parasitize humans collected from 13 sites along the Chinese-Russian border. The presence of the bacteria was determined by detecting its specific citrate synthase (gltA) partial gene and outer membrane protein A (ompA) partial gene. Only Ixodes persulcatus Schulze was found to be naturally infected with C. R. tarasevichiae, which had an overall prevalence of 1.53% in both sexes. C. R. tarasevichiae is an emerging, tick-borne human pathogen and this finding may partially explain recent human cases of infection by this organism in China. Public health authorities should be aware of the potential risk posed by the transmission of this bacterium to humans by ticks.

Early and non- early surgery for ruptured intracranial aneurysms: analysis of 184 cases / 中华急诊医学杂志

Objective To compare the therapeutic efficacy between emergency and non-emergency operation for ruptured intracranial aneurysms. Method A retrospective analysis of 184 patients with ruptured intracranial aneurysms the Second Affiliated Hospital Zhejiang University College of Medicine, admitted from Dec 2008 to Sep 2009, was carried out to evaluate the efficacy of operation to be done earlier. The patients were divided into 2groups according to the time of surgery. In the early operation group ( n = 102), the patients were operated on within 3 days of rupture of aneurysms, and in the delayed operation group ( n = 82), the patients were operated on after 3 days. The comparison in the rate of rebleeding before surgery, rate of complete occlusion of the ruptured aneurysm and rate of major complications such as cerebral infarction and hydrocephalus between two groups was made. The Glasgow outcome scale (GOS) scores of these patients were also evaluated by 6- 12 months follow-up after operation. Results Preoperative re-bleeding happened in 2 patients of the early operation group and in 7 patients of the delayed operation group. The rates were significantly different ( P ＜ 0.05). The complete occlusion rate in the early operation group was 91.2 % ( 93/102 ), while was 80.5 % ( 66/82 ) in the delayed operation group (P＜0.05). There were no statistically significant differences in post-operative cerebral infarction rate, post-operative hydrocephalus rate or GOS scores on follow-up between two groups. Conchusions Early operation can significantly reduce the re-bleeding before surgery, reducing the risk of death and disability. In early operation, the continuous lumbar drainage by cannulation and other methods can be used to reduce intracranial pressure, significantly increasing the rate of complete occlusion, and promoting rehabilitation.

Observing thermal injury of rabbit brain in laser interstitial themotherapy and evaluating changed structure of Mood brain barrier in acute stage / 中华急诊医学杂志

Objective To observe ultramicro pathologic change of rabbit brain central damaged tissue and peripheral tissue after LOT, to evaluate the changed structure of blood brain barrier (BBB) of peripheral tissue in acute stage. Method Seventy Newzealand rabbits were randomly screened from Zhejiang University Animal Experiment Center. By stereotaxic technique, semiconductor surgica laser fibers were inserted into right frontal lobes and heat treated to randomly build LITT Group A (2 W, 600 s, n = 20) and LITT Group B (15 W, 100 s, n = 20) brain damaged models successfully. Other 15 nomal rabbits were randomly distributed as mannitol perfusion group and fake operation group. The ultramicro structures in central thermodamaged tissue were observed with transmission electro microscope after LITT 3 h,6 h,12 h,24 h. In peripheral tissue, ultramicro morphologic changes of brain vessels and BBB were evaluated. S100B protein in serum and BBB indexe were measured at different stages post LITT. Experimental data were treated as one-factor analysis of variance and q test. Results The brain damage center connected the tip of laser fiber and turn into thermodamage tissue. The main structure changes were cytoclasis, damnification of cell membrum, swelling of cell organelle such as mitochondrion, endoplasmic reticulurn,disappearance of mitochondrion and sparseness of cytoplasm in local tissure. Heat energy conducted to damage peripheral tissue, some cells occured apoptosis in different stage. In acute stage after LITT, contracted capillary vessel, oncreted red cell, swell endothelium cell, broken base membrum, wide around clearance and destroyed aperture structure were identified. The levels of serum S100B and BBB indexe dramatically rised. The opening time of BBB in peripheral tissue was longer than mannital perfusion group. However at 24 h post LITT, they began to recover in Group A. The difference of serum S100B and BBB indexe between Group A and Group B has statistical significance ( P =0.0087). Conclusions With semiconductor laser heat treatment and stereotaxic techniqe, definite cells cytoclasis, cell membrance structures and chondriosome damage could be performed obviously in rabbit brain thermotherapy point. Apoptosis could be found in peripheral tissue, BBB could be opened in an acute stage. The opening time course of BBB was shortened in those LITT cases with small power. It shew us a new method to perform a safe and exact damage zone of brain for functional neurosurgery.

The occurrence of traumatic cavotid carernous fistla after fracture of basilaris cranii and its associated factors with outcome / 中华急诊医学杂志

Objective To analyze the occurrence of traumatic carotid cavemons fistula (TCCF) resulted from the fracture of basilaris cranii, in order to find out the related factors to outcomes and to discuss the approaches to improving prognosis.Method Data of 312 patients with the fracture of skull base complicatcd with TCCF con-firmed angiography from 1999 to 2005 were analyzed. These patients were classified into patients with disable and patients without disabed. The factors potentially impacting on outcomes were analyzed. Results The overall inci-dence of TCCF in 312 patients with fracture of basilaris cranii was 3.8% .The incideucs of TCCF occurred in pa-tients with the fracture of anterior fossa, middle fossa and posterior fossa accounted for 2.4%, 8.3 % and 1.7 %, respectively. Between two cohorts of patients, there were no difference in age, gender, number of embelization proce-dares performed and the time from injury to appearence of the first symptom except the differencc in time from ap-pearence of the first symptom to the intravascular embohzation performed (P>0.05). Conclusions A relatively high incidence of TCCF occurs in patients with middle fossa fractures, especially those with transverse or oblique fractures. Prompt diagnosis and intervention can not be emphasized in case of patients with TCCF, and non inva-sive techniques for the early detection of TCCF under certain circumstance after brain or facial trauma should be considered so as to avoid a miss in the early diagnosis of middle fossa fracture to ensure favourable outcomes.

EFFECTS OF FUROSEMIDE ON ACTION POTENTIAL AND CONTRACTILE FORCE OF ISOLATED TOAD ATRlAL MYOCARDIUM / 中国药理学通报

Using floating microelectrode, the effects of furosemide on action potential and contractile force were studied in isolated toad atrial myocardium. Furosemide increased the force of contraction of toad right atrial myocardium, amplitude and dV/dtmax of action potential, and prolonged action potential duration at 50% repolari-zation (APD50), but the APD25, APD90 and sinus cycle length ( SCL) were not influenced. The positive intropic effect of furosemide could be blocked by Verapamil. These results indicated that furosemide could promote the Ca++ inward current.