59 research outputs found
Dynamic temporary blood facility location-allocation during and post-disaster periods
The key objective of this study is to develop a tool (hybridization or integration of different techniques) for locating the temporary blood banks during and post-disaster conditions that could serve the hospitals with minimum response time. We have used temporary blood centers, which must be located in such a way that it is able to serve the demand of hospitals in nearby region within a shorter duration. We are locating the temporary blood centres for which we are minimizing the maximum distance with hospitals. We have used Tabu search heuristic method to calculate the optimal number of temporary blood centres considering cost components. In addition, we employ Bayesian belief network to prioritize the factors for locating the temporary blood facilities. Workability of our model and methodology is illustrated using a case study including blood centres and hospitals surrounding Jamshedpur city. Our results shows that at-least 6 temporary blood facilities are required to satisfy the demand of blood during and post-disaster periods in Jamshedpur. The results also show that that past disaster conditions, response time and convenience for access are the most important factors for locating the temporary blood facilities during and post-disaster periods
HIV-Specific Antibodies Capable of ADCC Are Common in Breastmilk and Are Associated with Reduced Risk of Transmission in Women with High Viral Loads
There are limited data describing the functional characteristics of HIV-1 specific antibodies in breast milk (BM) and their role in breastfeeding transmission. The ability of BM antibodies to bind HIV-1 envelope, neutralize heterologous and autologous viruses and direct antibody-dependent cell cytotoxicity (ADCC) were analyzed in BM and plasma obtained soon after delivery from 10 non-transmitting and 9 transmitting women with high systemic viral loads and plasma neutralizing antibodies (NAbs). Because subtype A is the dominant subtype in this cohort, a subtype A envelope variant that was sensitive to plasma NAbs was used to assess the different antibody activities. We found that NAbs against the subtype A heterologous virus and/or the woman's autologous viruses were rare in IgG and IgA purified from breast milk supernatant (BMS) – only 4 of 19 women had any detectable NAb activity against either virus. Detected NAbs were of low potency (median IC50 value of 10 versus 647 for the corresponding plasma) and were not associated with infant infection (p = 0.58). The low NAb activity in BMS versus plasma was reflected in binding antibody levels: HIV-1 envelope specific IgG titers were 2.2 log10 lower (compared to 0.59 log10 lower for IgA) in BMS versus plasma. In contrast, antibodies capable of ADCC were common and could be detected in the BMS from all 19 women. BMS envelope-specific IgG titers were associated with both detection of IgG NAbs (p = 0.0001)and BMS ADCC activity (p = 0.014). Importantly, BMS ADCC capacity was inversely associated with infant infection risk (p = 0.039). Our findings indicate that BMS has low levels of envelope specific IgG and IgA with limited neutralizing activity. However, this small study of women with high plasma viral loads suggests that breastmilk ADCC activity is a correlate of transmission that may impact infant infection risk
Effects of calcitonin on the osseointegration of porous hydroxyapatite implant in osteoporosis model
BACKGROUND: Calcitonin can increase bone quantity and quality and reduce bone fracture occurrence. OBJECTIVE: To evaluate effects of calcitonin on the osseointegration of the porous hydroxyapatite implants and further on promoting the biological fixation of the implants in osteoporosis model. DESIGN, TIME AND SETTING: A randomized controlled experiment was performed at the Animal Experimental Center of Sun Yat-sun University and Histomorphometry Laboratory of Hong Kong University from September to December 2007 and from March to May 2008, respectively. MATERIALS: A total of 30 female SD rats of SPF grade and aging 5 months were randomly divided into three groups: sham operation + hydroxyapatite, ovariectomy (OVX) + hydroxyapatite, and OVX + calcitonin + hydroxyapatite groups, with 10 rats per group. METHODS: Postmenopausal osteoporosis models were established in the OVX + hydroxyapatite and OVX + calcitonin + hydroxyapatite groups using OVX method. While, rats in the sham operation + hydroxyapatite group were considered as the controls. The porous hydroxyapatite prostheses were inserted into the tibial plateum of the left tibia in each group, followed by a subcutaneous injection of calcitonin [5 U/(kg·d)] for twelve weeks in the OVX + calcitonin + hydroxyapatite group. MAIN OUTCOME MEASURES: Tibia carrying with implant was sectioned into sections. Skeletal density changes of lumbar vertebra were detected using bone histomorphometry and double energy ray bone density apparatus, bone quantity surrounding prosthesis was observed, and osseointegration rate of prosthesis was measured. RESULTS: Bone density of lumbar vertebra was gradually improved in the OVX + calcitonin + hydroxyapatite group. After calcitonin injection, osseointegration area rate increased 22.0%, which was nearly twice compared with the OVX + hydroxyapatite group (t=9.665, P < 0.05). CONCLUSION: In osteoporosis conditions, calcitonin can increase bone mass surrounding the implants and promote osseointegration by subcutaneous injection.link_to_subscribed_fulltex
Effects of surface modification and nanometer material on bone-prosthesis osseointegration in osteoporosis models
BACKGROUND: Hydroxyapatite (HA) coating can improve the initial and mid-term fixation of prosthesis. However, its long-term stabilization is unsatisfactory. A large number of studies report that nano-HA coating and surface modification of prosthesis can improve the osteointegration at prosthesis-bone interface. Yet, comparative study on osteointegration of nano-materials and surface modification has not been reported. OBJECTIVE: To compare effects of nano-materials and surface modification on osteointegration in osteoporosis (OP) model. DESIGN, TIME AND SETTING: A randomized control experiment was performed in the Animal Experimental Centre of Sun Yat-sun University from September to December 2007 and Histomorphometry Laboratory of the Hong Kong University from March to May 2008, respectively. MATERIALS: Porous HA-coating and surface modified nanometer prostheses sized 3 mm x 3 mm were provided by Department of Materials, South China University of Technology. METHODS: Thirty-two female SD rats, five-month old, were randomly divided into four groups: group A in which rats received sham surgery and was implanted with porous HA, group B in which rats received sham surgery and was implanted with smooth surface nano-HA, group C in which ovariectomized (OVX) rats was implanted with porous HA, and group D in which OVX rats was implanted with smooth surface nano-HA, with eight rats in each group. Rats in group C and D underwent ovariectomy to establish osteoporosis models. Porous and smooth surface HA prostheses were implanted into superior segments of tibia in each group. MAIN OUTCOME MEASURES: At 12 weeks after sacrifice, the bone quantity and osteointegration around the HA implant were observed and the osteointegration at the surface between bone and implant was calculated. RESULTS: Circled digit one; Osteointegration rate (OIS) in group C was 23.7%, which was significantly higher than group D 16.9% (P < 0.05). Circled digit two The OIS in the OVX groups was significantly less than sham surgery groups, reducing 30.8% and 13.0%, respectively. CONCLUSION: Surface modification can notably promote osteointegration at implant-bone interface in osteoporosis condition. The smooth surface of nano-HA prothesis fails to take advantage of the benefit of nano-HA. Referring to HA coating, surface modification of coating plays a more important role in promoting osteointegration, compared to coating material.link_to_subscribed_fulltex
Effects of surface modification and nanometer material on bone-prosthesis osseointegration in osteoporosis models
BACKGROUND: Hydroxyapatite (HA) coating can improve the initial and mid-term fixation of prosthesis. However, its long-term stabilization is unsatisfactory. A large number of studies report that nano-HA coating and surface modification of prosthesis can improve the osteointegration at prosthesis-bone interface. Yet, comparative study on osteointegration of nano-materials and surface modification has not been reported. OBJECTIVE: To compare effects of nano-materials and surface modification on osteointegration in osteoporosis (OP) model. DESIGN, TIME AND SETTING: A randomized control experiment was performed in the Animal Experimental Centre of Sun Yat-sun University from September to December 2007 and Histomorphometry Laboratory of the Hong Kong University from March to May 2008, respectively. MATERIALS: Porous HA-coating and surface modified nanometer prostheses sized 3 mm x 3 mm were provided by Department of Materials, South China University of Technology. METHODS: Thirty-two female SD rats, five-month old, were randomly divided into four groups: group A in which rats received sham surgery and was implanted with porous HA, group B in which rats received sham surgery and was implanted with smooth surface nano-HA, group C in which ovariectomized (OVX) rats was implanted with porous HA, and group D in which OVX rats was implanted with smooth surface nano-HA, with eight rats in each group. Rats in group C and D underwent ovariectomy to establish osteoporosis models. Porous and smooth surface HA prostheses were implanted into superior segments of tibia in each group. MAIN OUTCOME MEASURES: At 12 weeks after sacrifice, the bone quantity and osteointegration around the HA implant were observed and the osteointegration at the surface between bone and implant was calculated. RESULTS: Circled digit one; Osteointegration rate (OIS) in group C was 23.7%, which was significantly higher than group D 16.9% (P < 0.05). Circled digit two The OIS in the OVX groups was significantly less than sham surgery groups, reducing 30.8% and 13.0%, respectively. CONCLUSION: Surface modification can notably promote osteointegration at implant-bone interface in osteoporosis condition. The smooth surface of nano-HA prothesis fails to take advantage of the benefit of nano-HA. Referring to HA coating, surface modification of coating plays a more important role in promoting osteointegration, compared to coating material.link_to_subscribed_fulltex
Extending the CONSORT Statement to moxibustion
The STandards for Reporting Interventions in Clinical Trials Of Moxibustion (STRICTOM), in the form of a checklist and descriptions of checklist items, were designed to improve reporting of moxibustion trials, and thereby facilitating their interpretation and replication. The STRICTOM checklist included 7 items and 16 sub-items. These set out reporting guidelines for the moxibustion rationale, details of moxibustion, treatment regimen, other components of treatment, treatment provider background, control and comparator interventions, and precaution measures. In addition, there were descriptions of each item and examples of good reporting. It is intended that the STRICTOM can be used in conjunction with the main CONSORT Statement, extensions for nonpharmacologic treatment and pragmatic trials, and thereby raise the quality of reporting of clinical trials of moxibustion. Further comments will be solicited from the experts of the CONSORT Group, the STRICTA Group, acupuncture and moxibustion societies, and clinical trial authors for optimizing the STRICTOM. © 2013 Chung-wah Cheng et al.link_to_subscribed_fulltex
Contrasting responses in leaf nutrient-use strategies of two dominant grass species along a 30-yr temperate steppe grazing exclusion chronosequence
Grazing exclusion practices can be promising restoration techniques where ecosystem degradation follows from rapidly increasing grazing pressure, as widely observed in northern Chinese grasslands. However, the mechanisms of plant-soil interactions responsible for nutrient cycling restoration remain unclear. We examined the functional response of the two most dominant grass species with contrasting nutrient economies to a grazing exclusion chronosequence varying greatly in soil moisture and extractable N and P. The relative biomass of the nutrient acquisitive species Leymus chinensis increased while that of the nutrient conservative Stipa grandis decreased across the chronosequence. Leymus chinensis displayed increasing leaf nutrient concentration and decreasing nutrient resorption with time since grazing exclusion for both N and P. In contrast, S. grandis showed decreasing leaf N and P concentrations and largely stable nutrient resorption. These differences in plasticity, with respect to nutrient stoichiometry and resorption, suggest contrasting abilities of these two dominant species to compete for soil resources and/or differences in their affinity to the changing forms of soil available N and P likely occurring along the restoration gradient. Ecosystem trajectory of change after grazing exclusion appears therefore largely dependent on the nutrient use strategies of co-occurring dominant grassland species
Nonautonomous lump waves of a (3+1)-dimensional Kudryashov–Sinelshchikov equation with variable coefficients in bubbly liquids
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