Small Footprint Multilayered Millimeter-Wave Antennas and Feeding Networks for Multi-Dimensional Scanning and High-Density Integrated Systems

This paper overviews the state-of-the-art of substrate integrated waveguide (SIW) techniques in the design and realization of innovative low-cost, low-profile and low-loss (L3) millimeter-wave antenna elements, feeding networks and arrays for various wireless applications. Novel classes of multilayered antenna structures and systems are proposed and studied to exploit the vertical dimension of planar structures to overcome certain limita-tions in standard two-dimensional (2-D) topologies. The developed structures are based on two techniques, namely multi-layer stacked structures and E-plane corners. Differ-ent E-plane structures realised with SIW waveguide are presented, thereby demonstrating the potential of the proposed techniques as in multi-polarization antenna feeding. An array of 128 elements shows low SLL and height gain with just 200g of the total weight. Two versions of 2-D scanning multi-beam are presented, which effectively combine frequency scanning with beam forming networks. Adding the benefits of wide band performance to the multilayer structure, two bi-layer structures are investigated. Different stacked antennas and arrays are demonstrated to optimise the targeted antenna performances in the smallest footprint possible. These structures meet the requirement for developing inexpensive compact millimeter-wave antennas and antenna systems. Different structures and architectures are theoretically and experimentally studied and discussed for specific space- and ground-based appli-cations. Practical issues such as high-density integration and high-volume manufacturability are also addressed

Factors Affecting Tourists Satisfaction of Jordan as a Tourism Destination

This study aimed to examine the factors affecting tourist’s satisfaction of Jordan as a tourism destination. A Convenience sample of 500 tourists was selected from those who visited different Jordanian places. They asked to answer a set-scale questionnaire that measure tourist expectation and his/her perception toward destination image, emotional involvement, perceived outcome, self image and his satisfaction. Findings of the study indicated that Perceived outcomes, Jordan image and the emotional involvement had a significant impact on the tourists’satisfaction/ dissatisfaction. While self image, and perceived expectations had no influence. Furthermore, findings indicated that tourist’s satisfaction levels do not change according to gender, martial status, and education levels. But with different nationalities, ages, and monthly income the tourists had different level of satisfaction. Finally, many recommendations were recommended as follows: 1- Giving more attention to the Gulf of Aqaba and Dead Sea beaches and work on developing suitable protection and maintenance programs. 2 - Focusing on the development of promotional programs which aim to inform tourist about different festivals in Jordan. Also, spreading the festivals to all seasons of the year. 3- Increasing co-operation between tourism organizations in Jordan and other Arab countries in order to develop a good package of tourism programs at competitive prices. 4- Focusing on exploring new Foreign and Arab markets to attract tourists to visit Jordan

Pregnancy-Associated Pyogenic Sacroiliitis: Case Report and Review

Background: Pyogenic sacroiliitis occurs infrequently during the peripartum period. Case: A case at our institution and a review of the literature were analyzed. A total of 15 cases were discovered. The onset of illness was during pregnancy (40% of cases), within 3 weeks postpartum (40%) or post-abortion (20%), and the presentation was usually acute (< 7 days in 67% of cases). Frequent manifestations included localized pain in the hips or buttock, sacroiliac joint tenderness and fever. Computed tomography or magnetic resonance imaging revealed joint involvement in all cases tested. Microbiology was confirmed by blood (40%) or joint aspirate (75%), and most patients were treated with antibiotics. Surgical intervention took place in five cases. Pretermlabor was reported in only one case. All patients respondedwell to therapy without locomotive disability, and persistent pain was uncommon. Conclusion: Septic sacroiliitis should be considered in peripartum patients who present with fever and severe localized pain. Medical management is usually curative, and without an adverse effect on pregnancy

Experiments in the coordination of large groups of robots

The use of large groups of robots, generally called swarms, has gained increased attention in recent years. In this paper, we present and experimentally validate an algorithm that allows a swarm of robots to navigate in an environment containing unknown obstacles. A coordination mechanism based on dynamic role assignment and local communication is used to help robots that may get stuck in regions of local minima. Experiments were performed using both a realistic simulator and a group of real robots and the obtained results showed the feasibility of the proposed approach

Challenges for Malaria Elimination in Zanzibar: Pyrethroid Resistance in Malaria Vectors and Poor Performance of Long-Lasting Insecticide Nets.

Long-lasting insecticide treated nets (LLINs) and indoor residual house spraying (IRS) are the main interventions for the control of malaria vectors in Zanzibar. The aim of the present study was to assess the susceptibility status of malaria vectors against the insecticides used for LLINs and IRS and to determine the durability and efficacy of LLINs on the island. Mosquitoes were sampled from Pemba and Unguja islands in 2010--2011 for use in WHO susceptibility tests. One hundred and fifty LLINs were collected from households on Unguja, their physical state was recorded and then tested for efficacy as well as total insecticide content. Species identification revealed that over 90% of the Anopheles gambiae complex was An. arabiensis with a small number of An. gambiae s.s. and An. merus being present. Susceptibility tests showed that An. arabiensis on Pemba was resistant to the pyrethroids used for LLINs and IRS. Mosquitoes from Unguja Island, however, were fully susceptible to all pyrethroids tested. A physical examination of 150 LLINs showed that two thirds were damaged after only three years in use. All used nets had a significantly lower (p < 0.001) mean permethrin concentration of 791.6 mg/m2 compared with 944.2 mg/m2 for new ones. Their efficacy decreased significantly against both susceptible An. gambiae s.s. colony mosquitoes and wild-type mosquitoes from Pemba after just six washes (p < 0.001). The sustainability of the gains achieved in malaria control in Zanzibar is seriously threatened by the resistance of malaria vectors to pyrethroids and the short-lived efficacy of LLINs. This study has revealed that even in relatively well-resourced and logistically manageable places like Zanzibar, malaria elimination is going to be difficult to achieve with the current control measures

A Simple Reactive Obstacle Avoidance Algorithm and Its Application in Singapore Harbor

Autonomous surface craft (ASC) are increasingly attractive as a means for performing harbor operations including monitoring and inspection. However, due to the presence of many fixed and moving structures such as pilings, moorings, and vessels, harbor environments are extremely dynamic and cluttered. In order to move autonomously in such conditions ASC’s must be capable of detecting stationary and moving objects and plan their paths accordingly. We propose a simple and scalable online navigation scheme, wherein the relative motion of surrounding obstacles is estimated by the ASC, and the motion plan is modified accordingly at each time step. Since the approach is model-free and its decisions are made at a high frequency, the system is able to deal with highly dynamic scenarios. We deployed ASC’s in the Selat Pauh region of Singapore Harbor to test the technique using a short-range 2-D laser sensor; detection in the rough waters we encountered was quite poor. Nonetheless, the ASC’s were able to avoid both stationary as well as mobile obstacles, the motions of which were unknown a priori. The successful demonstration of obstacle avoidance in the field validates our fast online approach.Massachusetts Institute of Technology. Singapore-MIT Alliance in Research and Technology (SMART

Punicalagin Induces Serum Low-Density Lipoprotein Influx to Macrophages

High levels of circulating low-density lipoprotein (LDL) are a primary initiating event in the development of atherosclerosis. Recently, the antiatherogenic effect of polyphenols has been shown to be exerted via a mechanism unrelated to their antioxidant capacity and to stem from their interaction with specific intracellular or plasma proteins. In this study, we investigated the interaction of the main polyphenol in pomegranate, punicalagin, with apolipoprotein B-100 (ApoB100) that surrounds LDL. Punicalagin bound to ApoB100 at low concentrations (0.25–4 μM). Upon binding, it induced LDL influx to macrophages in a concentration-dependent manner, up to 2.5-fold. In contrast, another polyphenol which binds to ApoB100, glabridin, did not affect LDL influx. We further showed that LDL influx occurs specifically through the LDL receptor, with LDL then accumulating in the cell cytoplasm. Taken together with the findings of Aviram et al., 2000, that pomegranate juice and punicalagin induce plasma LDL removal and inhibit macrophage cholesterol synthesis and accumulation, our results suggest that, upon binding, punicalagin stimulates LDL influx to macrophages, thus reducing circulating cholesterol levels

Solving the Direction Field for Discrete Agent Motion

Models for pedestrian dynamics are often based on microscopic approaches allowing for individual agent navigation. To reach a given destination, the agent has to consider environmental obstacles. We propose a direction field calculated on a regular grid with a Moore neighborhood, where obstacles are represented by occupied cells. Our developed algorithm exactly reproduces the shortest path with regard to the Euclidean metric.Comment: 8 pages, 4 figure