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Water reuse for irrigated agriculture in Jordan: challenges of soil sustainability and the role of management strategies
Reclaimed water provides an important contribution to the water balance in water-scarce Jordan, but the quality of this water presents both benefits and challenges. Careful management of reclaimed water is required to maximize the nutrient benefits while minimizing the salinity risks. This work uses a multi-disciplinary research approach to show that soil response to irrigation with reclaimed water is a function of the management strategies adopted on the farm by the water user. The adoption of management methods to maintain soil productivity can be seen to be a result of farmers’ awareness to potentially plant-toxic ions in the irrigation water (70% of Jordan Valley farmers identified salinization as a hazard from irrigation with reclaimed water). However, the work also suggests that farmers’ management capacity is affected by the institutional management of water. About a third (35%) of farmers in the Jordan Valley claimed that their ability to manage salinization was limited by water shortages. Organizational interviews revealed that institutional awareness of soil management challenges was quite high (34% of interviewees described salinization as a risk from water reuse), but strategies to address this challenge at the institutional level require greater development
Transparent reporting of recruitment and informed consent approaches in clinical trials recruiting children with minor parents in sub-Saharan Africa: a secondary analysis based on a systematic review
BACKGROUND: Standardised checklists of items to be addressed in clinical study protocols and publications are promoting transparency in research. However, particular specifications for exceptional cases, such as children with minor parents are missing. This study aimed to examine the level of transparency regarding recruitment and informed consent approaches in publications of clinical trials recruiting children with minor parents in sub-Saharan Africa. We thereby focused particularly on the transparency about consenting persons (i.e. proxy decision-makers) and assessed the need to expand reporting guidelines for such exceptional cases. METHODS: We conducted a secondary analysis of clinical trial publications previously identified through a systematic review. Multiple scientific databases were searched up to March 2019. Clinical trial publications addressing consent and potentially recruiting children with minor parents in sub-Saharan Africa were included. 44 of the in total 4382 screened articles met our inclusion criteria. A descriptive analysis was performed. RESULTS: None of the included articles provided full evidence on whether any recruited children had minor parents and how consent was obtained for them. Four proxy decision-maker types were identified (parents; parents or guardians; guardians; or caregivers), with further descriptions provided rarely and mostly in referenced clinical trial registrations or protocols. Also, terminology describing proxy decision-makers was often used inconsistently. CONCLUSIONS: Reporting the minimum maternal age alongside maternal data provided in baseline demographics can increase transparency on the recruitment of children with minor mothers. The CONSORT checklist should require clinical trial publications to state or reference exceptional informed consent procedures applied for special population groups. A standardized definition of proxy decision-maker types in international clinical trial guidelines would facilitate correct and transparent informed consent for children and children with minor parents. STUDY REGISTRATION: CRD42018074220
Predicting the outcome of heart failure against chronic-ischemic heart disease in elderly population – Machine learning approach based on logistic regression, case to Villa Scassi hospital Genoa, Italy
Totally 167 patients were admitted at cardiology ward in Villa Scassi hospital, Genoa, Italy. We worked with two control groups: heart failure 59 patients (mean age: 71.37 ± 13.27 years) and chronic-ischemic heart disease 108 patients (mean age: 68.85 ± 11.3 years). Nine parameters: Hb, Serum Creatinine, LDL, HDL, Triglycerides, ALT, AST, hs-cTnI, CRP were evaluated onset to hospitalization. We aimed to identify significant independent predictors relative to the outcome of heart failure versus chronic-ischemic heart disease and select combination of biochemical parameters in logistic regression-based model that would provide on average excellent discrimination to the outcome of heart failure versus chronic-ischemic heart
disease in elderly population. Applying 20-fold repeated stratified cross-validation, 4:1 train/test ratio split, we have found that probability of heart failure, provides best discrimination of the outcome of heart failure against chronic-ischemic heart disease
Basilar artery fenestration
The posterior circulation of the brain constitutes the vertebrobasilar system and
its branches, which are responsible for about 30% of the brain’s blood supply.
The aim of this study was to describe the anomalies of the basilar artery, especially
fenestrations. For that purpose, we examined 50 patients with computed
tomography (CT) angiography during an 8-month period. In the CT reports of
2 (4%) patients of the 50 analysed, fenestration was found at the proximal basilar
trunk. The two fenestrations in our series were not associated with aneurysms.
No collateral branches originated from the two limbs of the fenestration. In conclusion,
basilar artery fenestrations are a rare finding. The data derived from this
study are useful teaching material for anatomists, and for the radiologists and
neurosurgeons they are important for diagnostic and intervention procedures
such as CT, magnetic resonance imaging, angiography, and surgical and endovascular
procedures. (Folia Morphol 2011; 70, 2: 80–83
Finding an Effective Metric Used for Bijective S-Box Generation by Genetic Algorithms
In cryptography, S-box is a basic component of symmetric key algorithms which performs nonlinear substitution. S-boxes need to be highly nonlinear, so that the cipher can resist linear cryptanalysis.
The main criteria for cryptographically strong (n Ă— n) S-box are:
• High non linearity;
• High algebraic degree;
• Balanced structure;
• Good auto correlation properties.
Our task was to give some suggestions for finding an effective metric used for generation bijective optimal S-Box. Because of the given problem’s complexity, our group considered different approaches and we gave a few suggestions for problem solving
Salen Mn Complexes Mitigate Radiation Injury in Normal Tissues
Salen Mn complexes, including EUK-134, EUK-189 and a newer cyclized analog EUK-207, are synthetic SOD/catalase mimetics that have beneficial effects in many models of oxidative stress. As oxidative stress is implicated in some forms of delayed radiation injury, we are investigating whether these compounds can mitigate injury to normal tissues caused by ionizing radiation. This review describes some of this research, focusing on several tissues of therapeutic interest, namely kidney, lung, skin, and oral mucosa. These studies have demonstrated suppression of delayed radiation injury in animals treated with EUK-189 and/or EUK-207. While an antioxidant mechanism of action is postulated, it is likely that the mechanisms of radiation mitigation by these compounds in vivo are complex and may differ in the various target tissues. Indicators of oxidative stress are increased in lung and skin radiation injury models, and suppressed by salen Mn complexes. The role of oxidative stress in the renal injury model is unclear, though EUK-207 does mitigate. In certain experimental models, salen Mn complexes have shown “mito-protective” properties, that is, attenuating mitochondrial injury. Consistent with this, EUK-134 suppresses effects of ionizing radiation on mitochondrial function in rat astrocyte cultures. In summary, salen Mn complexes could be useful to mitigate delayed radiation injury to normal tissues following radiation therapy, accidental exposure, or radiological terrorism. Optimization of their mode of delivery and other key pharmaceutical properties, and increasing understanding of their mechanism(s) of action as radiation mitigators, are key issues for future study
Extreme Fluctuations in Wnt/beta-Catenin Signaling as an Approach for Colon Cancer Prevention and Therapy
Abstract: Mutations in the Wnt/beta-catenin (Wnt) signaling pathway initiate most cases of sporadic colon cancers (CC); therefore one approach for CC prevention and therapy is to suppress Wnt activity. However, the prolonged suppression of the signaling pathway is detrimental to the intestinal stem cells that rely on Wnt signaling for survival. Furthermore, CC cells exposed for an extended period of time to a single Wnt signaling -modulating agent may develop resistance to it. A possible solution is suggested by our findings that: (a) butyrate, a colonic metabolite of dietary fiber, and synthetic histone deacetylase inhibitors that mimic the effects of butyrate, hyperactivate Wnt transcriptional activity in CC cells with mutations in the pathway, and (b) high fold changes of Wnt signaling induce high apoptotic levels in the mutated cells. Therefore, diet-and drug-based regimens that result in alternating periods of suppressed and hyper-activated Wnt signalling may become powerful anti-CC preventive and therapeutic approaches. The hypothesis can be tested by (1) evaluating the effects of drug-and dietbased regimens, which induce maximal fluctuations in Wnt signaling, on the adenoma burden of Apc/min mice, an established in vivo model of intestinal cancer, (2) epidemiological studies analyzing the dietary habits, such as daily fasting hours and fiber intake, of healthy individuals and patients with positive colonoscopies, and 352 D. L. Lazarova and M. Bordonaro (3) examining the ability of different diets to produce colonic lumen content with apoptotic and Wnt-modulatory functions
On fatigue behavior of two spring steels. Part I: Wöhler curves and fractured surfaces
Symmetric fatigue in two spring steels is investigated in three groups of specimens. One of the groups (Steel EN10270-1SH/ DIN 17223C – C 0.82%, Mn 0.76%, Si 0.26%) has experienced rotating-bending fatigue in air, and the other two groups (Steel BS250A53/ DIN 55Si7 – C 0.56%, Mn 0.81%, Si 1.85%), torsion fatigue in-air and corrosion environment. Fatigue life-time data are obtained for both spring steels, and their corresponding Wöhler curves plotted and mathematically described. Surface short fatigue cracks are observed from origin to fracture by using acetate-foil replication technique, and their length, a, measured at the corresponding number of fatigue cycles, N. Those data are presented in plots “Crack lengths, a – Cycles, N” and a comparison made between both the steels. The fractured surfaces of all specimens have been studied and analyzed by the scanning-electron microscopy method
On fatigue behaviour of two spring steels. Part II: Mathematical models
Symmetric fatigue in two spring steels is investigated in three groups of specimens. One of the groups (Steel EN10270-1SH/ DIN 17223C – C 0.82%, Mn 0.76%, Si 0.26%) has experienced rotating-bending fatigue in air, and the other two groups (Steel BS250A53/ DIN 55Si7 – C 0.56%, Mn 0.81%, Si 1.85%), torsion fatigue in-air and corrosion environment. All experiments include testing to fracture, applying acetate-foil replication technique, replica monitoring of short crack surface growth, length measuring of propagating cracks, a, at the corresponding number of fatigue cycles, N. Data obtained from replica monitoring are presented in plots “Crack lengths, a – Cycles, N”, and used for calculating fatigue crack growth rates, da/dN, and graphical presentations “Crack growth rates, da/dN – Crack lengths, a”. A mathematical description of da/dN – a is presented by introducing a parabolic-linear model in different versions for each of the steels. The model versions are verified through comparing the experimental fatigue lifetimes with those calculated by the proposed model version
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