Practical Bloom filter based epidemic forwarding and congestion control in DTNs: A comparative analysis

International audienceEpidemic forwarding has been proposed as a forwarding technique to achieve opportunistic communication in delay tolerant networks (DTNs). Even if this technique is well known and widely referred, one has to address several practical problems before using it. Unfortunately, while the literature on DTNs is full of new techniques, very little has been done in comparing them. In particular, while Bloom filters have been proposed to exchange information about the buffer content prior to sending information in order to avoid redundant retransmissions, up to our knowledge no real evaluation has been provided to study the tradeoffs that exist for using Bloom filters in practice. A second practical issue in DTNs is buffer management (resulting from finite buffers) and congestion control (resulting from greedy sources). This has also been the topic of several papers that had already uncovered the difficulty to acquire accurate information mandatory to regulate the data transmission rates and buffer space. In this paper, we fill this gap. We have been implementing a simulation of different proposed congestion control schemes for epidemic forwarding in ns-3 environment. We use this simulation to compare different proposed schemes and to uncover issues that remain in each one of them. Based on this analysis, we proposed some strategies for Bloom filter management based on windowing and describe implementation tradeoffs. Afterwards, we propose a back-pressure rate control as a well as an aging based buffer managing solution to deal with congestion control. By simulating our proposed mechanisms in ns-3 both with random-waypoint mobility and realistic mobility traces coming from San-Francisco taxicabs, we show that the proposed mechanisms alleviate the challenges of using epidemic forwarding in DTN

The effect of education of cardiopulmonary resuscitation (C.P.R) on knowledge of nursing staff and C.P.R team members in a hospital in Kerman province

Approximately half of the cardiac arrest mortality occurred in hospitals and nurses are one of the key persons in acceptance duty. For proper performing resuscitation nurses have to have theoretical knowledge and practical skill. Literature review shows knowledge as well as skill deficiency among nurses in this topic. To investigate the effect of CPR education by booklets and brushers on knowledge of Emergency staffs and members of CPR team in one Kerman province hospital at2008. In this quasi-experimental study، to assess CPR knowledge a questionnaire consists of 15 items was used. After confirming the validity and reliability، it was distributed among participants (CPR team and emergency ward staffs). After pretest، booklets and brushers (according to the new protocol of CPR for each part of subject) were distributed among participants. Post test was done after 8 days and data were analyzed by SPSS17. According to the results، after education، knowledge scores of staff about CPR was significantly more than that of before education (P<0.001). Mean of knowledge scores of ICU and CCU nurses in both pre test and post test were higher than that of others (P<0.001). It can be concluded that education، even if it would be inexpensive and brief، has positive effect on improvement of nurses’ knowledge. This study highlights the role of education in development of competency and confident of nurses in the topic of CPR Keywords: Education, knowledge, Cardiopulmonary Resuscitation team, nurs

Effects of Probiotic Cells on the Mechanical and Antibacterial Properties of Sodium-Caseinate Films

Background and Objective: Food processing conditions such as heat, mechanical or osmotic stress can lead to considerable losses of probiotics’ survival in food. Recently, the addition of probiotics into edible films has been proposed as an emerging technology for the delivery of probiotic cells. In this study, Lactobacillus acidophilus and Lactobacillus casei cells were incorporated into sodium caseinate matrix to develop a probiotic-based film which can improve food safety.Material and Methods: Probiotic cells were separately added to the film forming solutions and the active films were prepared by casting method. The physical, optical and mechanical characteristics of the films were examined. Color properties were determined using a colorimeter and the mechanical properties of the films were evaluated by an Instron Universal Testing Machine. The viability of Lactobacillus acidophilus and Lactobacillus casei in the films was determined during a period of 12 days. The antibacterial activities of the films were also tested against Listeria monocytogenes on Trypticase Soy Agar medium at 4°C.Results and Conclusion: Results demonstrated that lactic acid bacteria cells remained viable during a storage period of 12 days (&gt; 4 Log CFU cm-2). The incorporation of lactic acid bacteria cells into the film polymer had no significant effect on tensile strength (p&gt;0.05) whereas it significantly improves the appearance of films. Indeed, samples covered with the lactic acid bacteria film displayed higher anti-listerial activity than the control group on day 6 of preservation (p≤0.05). These findings show that the sodium caseinate film containing lactic acid bacteria cells can be used as a new effective packaging method for improving food safety

OISA: Architecting an Optical In-Sensor Accelerator for Efficient Visual Computing

Targeting vision applications at the edge, in this work, we systematically explore and propose a high-performance and energy-efficient Optical In-Sensor Accelerator architecture called OISA for the first time. Taking advantage of the promising efficiency of photonic devices, the OISA intrinsically implements a coarse-grained convolution operation on the input frames in an innovative minimum-conversion fashion in low-bit-width neural networks. Such a design remarkably reduces the power consumption of data conversion, transmission, and processing in the conventional cloud-centric architecture as well as recently-presented edge accelerators. Our device-to-architecture simulation results on various image data-sets demonstrate acceptable accuracy while OISA achieves 6.68 TOp/s/W efficiency. OISA reduces power consumption by a factor of 7.9 and 18.4 on average compared with existing electronic in-/near-sensor and ASIC accelerators.Comment: 7 page

Evaluation of the Association between Serum Levels of Vitamin D and Benign Paroxysmal Positional Vertigo (BPPV): A Case-Control Study

Background: Benign paroxysmal positional vertigo (BPV) is the most common cause of the high prevalence of vertigo. Today, BPV is caused by the separation of autochthonous particles from the macular atrial. As a result, these particles float in a semicircular canal and change position by gravity. The majority of vertigo causes arise from the inner ear. Aim: This study aims to measure the vitamin D level in patients with BPPV who visited Loghman Hakim Hospital clinics and compare the results with controls. Methods: This comparative study evaluated the effect of vitamin D on reducing BPV. Demographic information of patients was collected through interviews. The physical examinations were recorded through a questionnaire. For the group with BPPV, we did the Epley maneuver and measured the vitamin D level. We compared the vitamin D levels of these patients with the matched control group. Results: In this study, 148 patients were evaluated. Sixty-three patients were male, and 85 patients were female. All case and control patients were tested for vitamin D levels. Of 93 patients with benign vertigo, 39 (41.9%) patients had normal vitamin D levels, and 54(58.1%) patients had below normal. In the control group, 43 (78.2%) patients had normal vitamin D, and 12 (21.8%) patients had less than normal. There was a statistically significant difference between the two groups. Conclusion: The present study indicated that BPV was more prevalent in people with vitamin D deficiency, and vitamin D treatment could effectively control and reduce the prevalence of this disease