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Fossil-fueled development (SSP5): An energy and resource intensive scenario for the 21st century
No full textAbstractThis paper presents a set of energy and resource intensive scenarios based on the concept of Shared Socio-Economic Pathways (SSPs). The scenario family is characterized by rapid and fossil-fueled development with high socio-economic challenges to mitigation and low socio-economic challenges to adaptation (SSP5). A special focus is placed on the SSP5 marker scenario developed by the REMIND-MAgPIE integrated assessment modeling framework. The SSP5 baseline scenarios exhibit very high levels of fossil fuel use, up to a doubling of global food demand, and up to a tripling of energy demand and greenhouse gas emissions over the course of the century, marking the upper end of the scenario literature in several dimensions. These scenarios are currently the only SSP scenarios that result in a radiative forcing pathway as high as the highest Representative Concentration Pathway (RCP8.5). This paper further investigates the direct impact of mitigation policies on the SSP5 energy, land and emissions dynamics confirming high socio-economic challenges to mitigation in SSP5. Nonetheless, mitigation policies reaching climate forcing levels as low as in the lowest Representative Concentration Pathway (RCP2.6) are accessible in SSP5. The SSP5 scenarios presented in this paper aim to provide useful reference points for future climate change, climate impact, adaption and mitigation analysis, and broader questions of sustainable development
Impact of Tamsulosin, Tolterodine and drug-combination on the outcomes of lower urinary tract symptoms secondary to post-ureteroscopy ureteral stent: A prospective randomized controlled clinical study
No full textAbstractObjectivesTo compare the role of alpha-blocker (Tamsulosin) monotherapy, anticholinergic (Tolterodine) monotherapy or combination of both drugs versus analgesics in improving post-ureteroscopy (URS) lower urinary tract symptoms related to double-J ureteral stent.Patients and methodsBetween January 2009 and June 2013, 160 consecutive patients with ureteric stones were included in this study at 2 tertiary care centers’. Patients were randomized into 4 groups; group A (n=40) received 0.4mg Tamsulosin once a day, group B (n=40) received 4mg Tolterodine once a day, group C (n=40) received Tamsulosin 0.4mg and Tolterodine 4mg once a day and group D (n=40) as a control group, received placebo once a day. All patients received analgesics on demand. Pre-treatment evaluation was done followed by among-groups comparison after 14 days including ureteral stent symptom questionnaire (USSQ) [Urinary symptom index (USI), pain symptom index (PSI), general health index (GHI), work perform index (WPI), need for pain killer (PK), need for analgesia, visual analogue scale (VAS) for pain and quality of life (QOL)]. Side effects were recorded and compared.ResultsOut of 160 patients, 153 patients (40, 38, 37 and 38 patients in groups A, B, C and D, respectively) completed the study with a mean age of 34.3±7.6 (20–50) years. All groups were comparable in terms of age, gender, stone size and stone location, USSQ items and QOL. After 14 days, the USSQ and QOL were significantly lower in group A, B and C in comparison with group D (p<0.05). Patients in group C had significantly much improvement than those of groups A and B (p<0.05).ConclusionCombination of alpha blockers (Tamsulosin) and Anticholinergics (Tolterodine) seems to significantly improve post-URS lower urinary tract symptoms secondary to ureteral stents with lower need for analgesia and better quality of life. Adverse effect of used drugs mentioned as transient and tolerated by the patients without need for auxiliary medication
Development of a slender continuum robotic system for on-wing inspection/repair of gas turbine engines
No full textAbstractThe maintenance works (e.g. inspection, repair) of aero-engines while still attached on the airframes requires a desirable approach since this can significantly shorten both the time and cost of such interventions as the aerospace industry commonly operates based on the generic concept “power by the hour”. However, navigating and performing a multi-axis movement of an end-effector in a very constrained environment such as gas turbine engines is a challenging task. This paper reports on the development of a highly flexible slender (i.e. low diameter-to-length ratios) continuum robot of 25 degrees of freedom capable to uncoil from a drum to provide the feeding motion needed to navigate into crammed environments and then perform, with its last 6 DoF, complex trajectories with a camera equipped machining end-effector for allowing in-situ interventions at a low-pressure compressor of a gas turbine engine. This continuum robot is a compact system and presents a set of innovative mechatronics solutions such as: (i) twin commanding cables to minimise the number of actuators; (ii) twin compliant joints to enable large bending angles (±90°) arranged on a tapered structure (start from 40mm to 13mm at its end); (iii) feeding motion provided by a rotating drum for coiling/uncoiling the continuum robot; (iv) machining end-effector equipped with vision system. To be able to achieve the in-situ maintenance tasks, a set of innovative control algorithms to enable the navigation and end-effector path generation have been developed and implemented. Finally, the continuum robot has been tested both for navigation and movement of the end-effector against a specified target within a gas turbine engine mock-up proving that: (i) max. deviations in navigation from the desired path (1000mm length with bends between 45° and 90°) are ±10mm; (ii) max. errors in positioning the end-effector against a target situated at the end of navigation path is 1mm. Thus, this paper presents a compact continuum robot that could be considered as a step forward in providing aero-engine manufacturers with a solution to perform complex tasks in an invasive manner
Gallstone ileus presenting as intussusception: A case report
No full textAbstractBackgroundGallstone ileus is a complication of acute cholecystitis that accounts for 25% of bowel obstruction cases in the elderly. To our knowledge, only one other case of gallstone ileus presenting as intussusception has been reported in the literature, and involved non-operative management with an unfavorable outcome.Case presentationHere we report the case of 69year old woman presenting with symptoms of acute small bowel obstruction with a surgical history significant for cholecystectomy 30 years prior. Computed tomographic imaging showed a target sign in the small bowel consistent with intussusception, but intraoperative diagnosis revealed this to be a gallstone. A simple enterolithotomy was conducted and the patient has since been symptom free.DiscussionGallstone ileus has a high mortality rate (12–17%) and is an important differential diagnosis to consider, especially as the elderly population throughout the world continues to grow.ConclusionAs radiographic features of gallstones are variable we suggest maintaining a high index of suspicion for gallstone ileus in any elderly patient presenting with SBO, even with a seemingly contradictory surgical history
Best practice during intrapartum care: A concept analysis
No full textAbstractRationaleBest practice is an abstract word open to different interpretations. The definition of best practice depends on the context.PurposeThe purpose is to explore the meaning of the concept of best practice within the context of intrapartum care.MethodThe concept of best practice was analysed using Wilson's method of concept analysis. Dictionaries, a thesaurus, and an internet search were employed. References of journals were used to identify extra sources. Data saturation was reached at 117 definitions and uses of the concept of best practice. The definitions and uses of the concept of best practice listed in column one were read repeatedly. Common and similar patterns of words were highlighted. Grouping of common attributes and connotations occurred in column two and further deductive analysis and synthesis occurred in column three where derived essential attributes of the concept of best practice were categorised.ResultsThree broad categories emerged, namely (1) Values as antecedents of best practice; (2) A three-phased interactive integrative cyclic process of best practice; (phase one: awareness; phase two: need analysis and interactive process; phase three: consolidation); and (3) Desired outcomes of best practice, with resultant theoretical definition of the concept best practice during intra-partum care. Theoretical validity was attained through 117 sources used.RecommendationThe results of the concept analysis of best practice should be used to develop a model to facilitate best practice during intra-partum care
The application of half-life in clinical decision making: Comparison of the pharmacokinetics of extended-release topiramate (USL255) and immediate-release topiramate
No full textAbstractObjectiveFor extended-release drugs with multi-compartment kinetics, such as topiramate, effective half-life (t1/2eff) may be a more clinically relevant parameter than elimination half-life (t1/2z). Using topiramate as a real-life example, the objective was to compare these half-life values for immediate- and extended-release topiramate (TPM-IR and USL255, respectively) to understand how drug pharmacokinetics may impact drug dosing recommendations.MethodsThe t1/2z and t1/2eff for USL255 and TPM-IR were compared using data from a phase I study (N=36) of 200mg USL255 administered once daily (QD) or TPM-IR twice daily (BID); effect of sampling duration on t1/2z was investigated. To further explore the relationship between half-life and dosing, steady-state PK was simulated for USL255 and TPM-IR.ResultsAs previously reported, mean t1/2z was similar between USL255 (80.2h) and TPM-IR (82.8h); TPM-IR t1/2z was ∼4 times longer than reported in the Topamax label (21h). In contrast, USL255 displayed a 1.5 fold longer t1/2eff (55.7 vs 37.1h for TPM-IR). When t1/2z was calculated from 48 to 336h, values ranged from 28.8 to 82.8h. Simulated steady-state PK profiles of USL255 QD exhibited reduced plasma fluctuations during a dosing interval vs TPM-IR QD or BID.SignificanceAs expected for the same moiety, t1/2z of USL255 and TPM-IR were similar; however, the longer t1/2eff for USL255 better approximates differences in recommend dosing (QD USL255 vs BID TPM-IR). Further, sampling duration impacted t1/2z, diminishing its predictive value for determining dose regimens; sampling-time differences may also explain t1/2z discrepancy between TPM-IR here versus Topamax label. As expected, steady-state simulations confirm that although TPM-IR has a long t1/2z, taking TPM-IR QD would lead to large plasma fluctuations. These data demonstrate that t1/2z may be less clinically meaningful than t1/2eff, and using t1/2z for some drugs may lead to erroneous conclusions regarding dosing regimens
Planning for community resilience to future United States domestic water demand
No full textAbstractCosts of repairing and expanding aging infrastructure and competing demands for water from other sectors such as industry and agriculture are stretching water managers’ abilities to meet essential domestic drinking water needs for future generations. Using Bayesian statistical modeling on past and present water use, we project domestic water demand in the context of four climate scenarios developed by the Intergovernmental Panel on Climate Change as part of the their Special Report on Emission Scenarios (SRES). We compare 2010 demand to projections of domestic water demand for the years 2030, 2060 and 2090 for the four SRES scenarios. Results indicate that the number of counties exceeding fifty percent or greater demand over 2010 levels increases through 2090 for two of the scenarios and plateaus around 2050 for the other two. Counties experiencing the largest increases in water demand are concentrated in the states of California, Texas, and isolated portions of the Mid-West, Southeast, and Mid-Atlantic. Closer examination of the spatial distribution of high demand counties reveals that they are typically found near or adjacent to metropolitan centers, potentially placing greater stress on already taxed systems. Identifying these counties allows for targeted adaptive management and policies, economic incentives, and legislation to be focused towards locations that are potentially the most vulnerable
Ammonium sulfate preparation from phosphogypsum waste
No full textAbstractThe Egyptian phosphogypsum waste is treated using sulfuric acid prior the ammonium sulfate production. The relevant factors that would affect the removal efficiencies of some impurities are studied. The optimum conditions of the treatment are 8 M sulfuric acid solution and 1/4 solid/liquid ratio for 30 min contact time at 80 °C. Moreover, the optimum conditions of the ammonium sulfate preparation are 10 g of the suspended impure or purified phosphogypsum in 40 ml of 3% ammonium sulfate solution (as initiator), 1/4 solid/liquid ratio at pH7 at an addition of an excess ammonium carbonate, and 150 rpm stirring speed for 4.0 h contact time at 55 °C as well as the 5 mg of barium chloride is added to remove the radium in the ammonium sulfate product. Finally, the ammonium sulfate is crystallized and the chemical analysis of the product shows 20% nitrogen and 23.6% sulfur. Therefore, the purity of the obtained ammonium sulfate is 95% from the purified phosphogypsum
Is trade liberalisation a vector for the spread of sugar-sweetened beverages? A cross-national longitudinal analysis of 44 low- and middle-income countries
No full textAbstractDoes trade and investment liberalisation increase the growth in sales of sugar-sweetened beverages (SSBs)? Here, for the first time to our knowledge, we test this hypothesis using a unique data source on SSB-specific trade flows. We test whether lower tariffs effectively increase imports of SSBs, and whether a higher level of imports increase sales of SSBs. Cross-national fixed effects models were used to evaluate the association between SSBs sales and trade liberalisation. SSBs per capita sales data were taken from EuroMonitor, covering 44 low- and middle-income countries from 2001 to 2014, SSBs import data were from TradeMap, Foreign Direct Investment data were from EuroMonitor, and data on applied tariffs on SSB from the World Trade Organisation tariffs database, all 2015 editions. The results show that higher tariffs on SSBs significantly decreased per capita SSB imports. Each one percent increase in tariffs was associated with a 2.9% (95% CI: 0.9%–5%) decrease in imports of SSBs. In turn, increased imports of SSBs were significantly associated with greater sales of SSBs per capita, with each 10 percent increase in imports (in US$) associated with a rise in sales of 0.36 L per person (95% CI: 0.08–0.68). Between 2001 and 2014, this amounted to 9.1 L greater sales per capita, about 40% of the overall rise seen in this period in LMICs. We observed that tariffs were inversely but not significantly associated with sales of SSBs. In conclusion, lower tariffs substantially increased imports of SSBs in LMICs, which translated into greater sales. These findings suggest that trade policies which lower tariff barriers to SSB imports can be expected to lead to increased imports and then increased sales of SSBs in LMICs, with adverse consequences for obesity and the diseases that result from it