Salivary biochemistry of the healthy oral ecosystem

Veerman, E.C.I. [Promotor]Brand, H.S. [Copromotor]Keijser, B.J.F. [Copromotor

Validation of Two Distributed, Autonomous Self-Organisation Algorithms for 802.11 Mesh Networks by Simulation

Two algorithms in a "self-organisation of multi-radio mesh networks" project are described and validated by simulation. As they are to be deployed over large networks the two challenges have been the scalability and stability of the solution. The basic approach is that of a distributed, light-weight, cooperative multiagent system that guarantees scalability. As the solution is distributed it is unsuitable to achieve any global optimisation goal --- in any case, we argue that global optimisation of mesh network performance in any significant sense is not feasible in real situations that are subjected to unanticipated perturbations and external intervention. Our overall goal is simply to reduce maintenance costs for such networks by removing the need for humans to tune the network settings. So stability of the algorithms is our main concern

Comparative evaluation of different types of bariatric surgery

Introduction. The use of bariatric surgery as a treatment for obesity has increased dramatically over the past few years. Because the results in obese patients with type 2 diabetes were so impressive, the International Diabetes Federation recommended considering bariatric surgery as an acceptable treatment option in patients with a BMI of 30-35 kg / m2 when diabetes cannot be adequately controlled with traditional therapies. The aim of the study is to compare the results of bariatric surgery in patients with metabolic syndrome according to the dynamics of body mass index and major orexigenic and anorexigenic hormones. Material and Methods. The results of surgical treatment of 19 patients with morbid obesity (5 men and 14 women) aged 44 ± 3.26 years with a body mass index ˃40 kg / m2 were evaluated. The control group consisted of 12 patients with normal body mass index and no manifestations of metabolic syndrome. Results. Our study also demonstrated the positive effect of LGAE on hormonal parameters with a decrease in ghrelin and leptin. This helped reduce BMI by 10.12% after 6 months. At the same time there is an increase in adiponectin and resistin. Conclusions. LGAE in patients with ghrelin-associated obesity is possible as an alternative intervention, given its good tolerability. Or, as the first preparatory stage of comprehensive surgical treatment in obese patients who are not good candidates for standard bariatric surgery

An edge index for the Quantum Spin-Hall effect

Quantum Spin-Hall systems are topological insulators displaying dissipationless spin currents flowing at the edges of the samples. In contradistinction to the Quantum Hall systems where the charge conductance of the edge modes is quantized, the spin conductance is not and it remained an open problem to find the observable whose edge current is quantized. In this paper, we define a particular observable and the edge current corresponding to this observable. We show that this current is quantized and that the quantization is given by the index of a certain Fredholm operator. This provides a new topological invariant that is shown to take same values as the Spin-Chern number previously introduced in the literature. The result gives an effective tool for the investigation of the edge channels' structure in Quantum Spin-Hall systems. Based on a reasonable assumption, we also show that the edge conducting channels are not destroyed by a random edge.Comment: 4 pages, 3 figure

A Topology Control-Based Self-Organisation in Wireless Mesh Networks

An algorithm for self-organisation that assigns the channels intelligently in multi-radio wireless mesh networks (MR-WMN) is important for the proper operation of MR-WMN. The aim of the self-organisation algorithm is to reduce the overall interference and increase the aggregate capacity of the network. In this paper, we have first proposed a generic self-organisation algorithm that addresses these two challenges. The basic approach is that of a distributed, light-weight, cooperative multiagent system that guarantees scalability. Second, we have evaluated the performance of the proposed self-organisation algorithm for two sets of initialisation schemes. The initialisation process results in a topology control of MR-WMN by way of spatial distribution of connectivity between the mesh nodes. The results have been obtained for realistic scenarios of MR-WMN node densities and topologies. We have shown in addition the need to develop non-transmit power control based algorithms to achieve a further increase in system capacity

Implementation of an enhanced recovery protocol for open and laparoscopic repair of ventral hernia

In the light of introduction of the concept of rapid recovery and the use of miniinvasive methods of treatment of postoperative ventral hernias, laparoscopic herniology attracts more and more attention of practical surgeons. This is due to virtually no wound complications, a reduction of the duration surgery and inpatient stay, which greatly improves social and labor adaptation. Objective. Evaluate the benefits of laparoscopic hernioplasty over the open one in the light of the concept of rapid recovery of ERAS – enhanced recovery after surgery. Materials and methods. For a comparative evaluation in the period from 2015 to 2017, 81 patients with postoperative ventral hernias were examined and surgically treated. According to the methods of hernioplasty, all patients were divided into two groups. The group 1 consisted of 38 (46.91 %) persons who underwent laparoscopic hernioplasty. The group 2 consisted of 43 (53.09 %) persons who underwent "open" allohernioplasty. The multimodal patient management program provided for common elements for both groups aimed at rapid recovery in the postoperative period. Results. The average duration of "open" hernioplasty was (143±25) min, laparoscopic – (98±14) min. The laparoscopic technique of hernioplasty does not require routine drainage of the abdominal cavity. When open allohernioplasty drainage was performed in 72 (69.20 %) cases. 5–6 hours after the surgery, using the "sublay" technique 66 (63.50 %), patients were able to take the vertical position and activate the motor activity within the hospital ward, the rest – during the first day. The postoperative stay in the stanionarium in the group of patients after the "open" hernioplasty was on average (7.98±1.36) days, after the laparoscopic operation – (2.63±1.28) days, respectively. Conclusions. Endovideo-surgical methods for the elimination of primary and postoperative ventral hernias are effective, safe, provide early mobilization of patients and their rapid labor and social adaptation due to a significant smaller number of early and late complications. Restrictions in the use of these treatments are considered to be hernia of a gigantic size, especially postoperative with pronounced joint process and severe concomitant diseases, in which the increase in intraabdominal pressure will be critical and will negatively affect the immediate results of surgical treatment

Clinical case of acute intestinal objection caused by a foreign body

Acute intestinal obstruction of various genesis remains one of the complex and urgent problems of emergency surgery. The reasons for unsatisfactory treatment results are late medical treatment and old age of such patients. The aim of the study was to shed light on a clinical case of acute intestinal obstruction on the background of diverticulosis of the distal colon. The patient K. was treated in 75 years with the analysis of X-ray examination X-ray, ultrasound examination of the abdominal cavity, computed tomography of the abdominal cavity. The diagnosis was: acute obstructive intestinal obstruction in the stage of decompensation on the background of concomitant pathology: Diverticulosis of the sigmoid and descending intestine. Diverticulitis. The patient underwent surgery: upper-middle laparotomy, total nasogastrointestinal intubation, retrograde intubation of the colon, suspended sigmostoma, drainage of the abdominal cavity. In the postoperative period for 3 days in the fecal mass found a foreign body – a polyethylene film measuring 35x50 cm. Thus, conducting a dynamic X-ray and sonographic examination in patients with acute obstruction of the digestive tract allows to confirm the presence of this pathology, but does not always help to establish the cause of this disease