Today, Wireless Sensor Network (WSN) is considered as one of the major research areas in computer network field. One of the many WSN functions is to provide sensing services in an unattended harsh ...environment. Sensed data need to be delivered to the data collection centre and to cope with the reliable network problem. Different routing protocols have been developed to deal with this problem. It is still a great challenge of the hierarchical routing protocol to operate efficiently in the presence of node failure. Therefore, a novel hierarchical routing protocol that addresses network survivability and redundancy issues is studied. Simulation results show superiority of the proposed protocol over the existing protocols.
There are few medium- and long-term data on the outcome of the use of proximal femoral structural allografts in revision hip arthroplasty. This is a study of a consecutive series of 40 proximal ...femoral allografts performed for failed total hip replacements using the same technique with a minimum follow-up of five years (mean 8.8 years; range 5 to 11.5 years). In all cases the stem was cemented into both the allograft and the host femur. The proximal femur of the host was resected in 37 cases. There were four early revisions (10%), two for infection, one for nonunion of the allograft-host junction, and one for allograft resorption noted at the time of revision of a failed acetabular reconstruction. Junctional nonunion was seen in three patients (8%), two of whom were managed successfully by bone grafting, and bone grafting and plating respectively. Instability was observed in four (10%). Trochanteric nonunion was seen in 18 patients (46%) and trochanteric escape in ten of these (27%). The mean Harris hip score improved from 39 to 79. Severe resorption involving the full thickness of the allograft was seen in seven patients (17.5%). This progressed rapidly and silently, but has yet to cause failure of any of the reconstructions. Profound resorption of the allograft may be related to a combination of factors, including a slow form of immune rejection, stress shielding and resorption due to mechanical disuse with solid cemented distal fixation, and the absence of any masking or protective effect which may be provided by the retention of the bivalved host bone as a vascularised onlay autograft. Although continued surveillance is warranted, the very good medium-term clinical results justify the continued use of structural allografts for failed total hip replacements with severe loss of proximal femoral bone.
We have previously described a simple and reproducible three-dimensional technique of CT for the measurement of the cover of the femoral head in acetabular dysplasia in adults. We now describe the ...application of this technique in ten patients with symptomatic dysplasia to assess the degree and direction of dysplasia and to measure the cover obtained at acetabular osteotomy. The indices obtained gave a useful indication of the degree and direction of the dysplasia and confirmed which components had been used most efficiently to achieve cover. The information is easily presented in graphical form and gives a clearer indication of the cover obtained than the indices derived from plain radiographs.
The South American tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), invaded Algeria in 2008 and caused severely significant devastation to tomato plants. This study designed to ...evaluate the thermal requirements and assess the influence of temperature on the life cycle of this devastating pest under controlled greenhouse environment. Through a series of experiments, we observed four generations of T. absoluta at various temperatures and relative humidity levels. We chased the population dynamics by using pheromone traps and revealed four overlapping generations, each of which corresponded to peaks in adult flying activity. These peaks were influenced by the greenhouse's temperature and humidity levels. The development of successive and overlapping generations of T. absoluta requires temperatures ranging from 25 to 30 °C, coupled with humidity levels between 58.5 % and 69.33 %. Additionally, the morphometric analysis of T. absoluta larvae allowed the identification of four larval stages characterized by lengths of 2.5 mm for the first instar, 2.5 to 4 mm for the second instar, 4.5 to 5.5 mm for the third instar, and 6 to 7 mm for the fourth instar. By studying the biology of T. absoluta and its thermal and hygrometric requirements, we can develop an integrated pest management strategy that efficiently battles against this destructive pest.
Stemless humeral components are being clinically investigated for reverse shoulder arthroplasty (RSA) procedures. There is, however, a paucity of basic science literature on the surgical parameters ...that influence the success of these procedures. Therefore, this cadaveric biomechanical study evaluated the neck shaft angle (NSA) of implantation on the survivability and performance of stemless RSA humeral components during cyclical loading.
Twelve paired cadaveric humeri were implanted with stemless RSA humeral components at NSAs of 135° and 145°. Implant–bone motion at the periphery of the implant was measured with 3 optical machine vision USB3 cameras outfitted with c-mount premium lenses and quantified with ProAnalyst software. A custom 3-dimensional loading apparatus was used to cyclically apply 3 loading directions representative of physiological states at 5 progressively increasing loading magnitudes. Stemless 135° and 145° implants were compared based on the maximum implant–bone relative distraction detected, as well as the survivorship of the implants throughout the loading protocol.
Primary fixation and implant biomechanical survivorship were substantially better in the 145° NSA implants. The 135° NSA implants elicited significantly higher implant–bone distractions during cyclical loading (P = .001), and implant survivorship was considerably lower in the 135° NSA specimens when compared to the 145° NSA specimens (135° NSA: 0%, 145° NSA: 50%) (P < .001).
NSA is a modifiable parameter that influences time-zero implant stability, as well as the early survivorship of the stemless RSA humeral components tested in this study. NSA resections of 145° appear to promote better stability than those utilizing 135° NSAs during early postoperative eccentric loads. Further studies are required to assess if other stemless reversed humeral implant designs have improved time-zero fixation at higher NSAs.
Objective The objective of the study was to evaluate the effectiveness of antibiotic-based polymethylmethacrylate (ab-PMMA) beads in achieving wound sterilization and graft preservation in patients ...with vascular graft infections. Methods We reviewed 31 patients treated for 37 graft infections over the past 5 years using ab-PMMA beads in a single institution. All patients were started on broad-spectrum antibiotics and later switched to targeted therapy based on intraoperative cultures for at least 6 weeks. All patients underwent multiple planned wound explorations, debridements and washouts. Cultures were obtained each time. Decision to do formal closure depended on culture results and wound appearance. All wounds were closed with a muscle flap. The endpoints included wound sterilization, limb salvage, recurrence of infection, and graft preservation. Results A total of 19 different organisms were cultured, and 48.6% of cases were polymicrobial, thereby accounting for a total of 60 isolates. The majority ( n = 27) received a mix of tobramycin/vancomycin PMMA beads; vancomycin beads ( n = 5); tobramycin beads ( n = 1); and gentamicin/vancomycin beads ( n = 4). Wound sterilization based on cultures was achieved in 32 of 34 wounds (94.1%). Of the cases, 5 underwent early graft removal, 3 with immediate reconstruction, and 1 case underwent a major amputation (2.7 %). Graft preservation was attempted in 32 cases (86.5%). No death occurred within 30 days. Limb salvage was achieved in 28 of the 32 preserved graft cases (87.5%) at a mean follow-up of 26 months (6 to 51 months). The long-term limb salvage rate for the cohort was 86.5%. Of the patients, 4 presented with recurrent graft infection and occlusion, causing acute limb ischemia and resulting in major amputation. The reinfection rate was 12.5% in the graft-preservation group and 11.4% in both the graft-preserved and the in situ replacement groups. Conclusion Sterilization of graft infection can be achieved with ab-PMMA beads followed by closure with muscle flap, resulting in an acceptable limb-salvage rate despite virulent or polymicrobial graft infection.
Metastasis is the hallmark of cancer that is responsible for the greatest number of cancer-related deaths. Yet, it remains poorly understood. The continuous evolution of cancer biology research and ...the emergence of new paradigms in the study of metastasis have revealed some of the molecular underpinnings of this dissemination process. The invading tumor cell, on its way to the target site, interacts with other proteins and cells. Recognition of these interactions improved the understanding of some of the biological principles of the metastatic cell that govern its mobility and plasticity. Communication with the tumor microenvironment allows invading cancer cells to overcome stromal challenges, settle, and colonize. These characteristics of cancer cells are driven by genetic and epigenetic modifications within the tumor cell itself and its microenvironment. Establishing the biological mechanisms of the metastatic process is crucial in finding open therapeutic windows for successful interventions. In this review, the authors explore the recent advancements in the field of metastasis and highlight the latest insights that contribute to shaping this hallmark of cancer.
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