Frequency and voltage partitioning in presence of renewable energy resources for power system (example: North Chile power network)

This paper investigates techniques for frequency and voltage partitioning of power network based on the graph-theory. These methods divide the power system into distinguished regions to avoid the spread of disturbances and to minimize the interaction between these regions for frequency and voltage control of power system. In case of required active and reactive power for improving the performance of the power system, control can be performed regionally instead of a centralized controller. In this paper, renewable energy sources are connected to the power network to verify the effect of these sources on the power systems partitioning and performance. The number of regions is found based on the frequency sensitivity for frequency partitioning and bus voltage for voltage partitioning to disturbances being applied to loads in each region. The methodology is applied to the north part of Chile power network. The results show the performance and ability of graph frequency and voltage partitioning algorithm to divide large scale power systems to smaller regions for applying decentralized controllers.Peer ReviewedPostprint (published version

Fibra efetiva para vacas em lactação.

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Impacts of citrus pulp addition and wilting on elephant grass silage quality.

The objective of this work was to evaluate the use of citrus pulp addition and wilting on fermentative characteristics, chemical composition as well as gas and effluent losses of elephant grass silage. The elephant grass (70 growth days) was collected manually; one portion was immediately chopped and another one was allowed to wilt in the sun for a period of 6 h and subsequently chopped for the production of silage. Experimental PVC silos (10 cm diameter x 30 cm height) were used and sand bags were placed at the bottom of the silos. Citrus pulp (80 g kg-1 of MN) was added at the beginning of ensilage. The ensiled material was manually compressed to provide a specific mass of approximately 600 kg m-3 of silage. After 60 days, the silos were opened; gas and effluent losses were calculated and we determined pH, dry matter (DM), crude protein(CP), neutral detergent fibre (NDF), lignin, ammonia nitrogen, ash and in vitro dry matter digestibility (IVDMD). We added 0 or 80 g kg-1 of citrus pulp to wilted and un-wilted elephant grass. We used a completely randomised design with a 2 x 2 factorial arrangement (wilted or un-wilted) x (with or without citrus pulp), totalling treatments with five repetitions. Average values were compared using the F test with a probability of 5%. The addition of citrus pulp resulted in reduced levels of NDF, lignin, ash, N-NH3 and pH and in increased values of DM and IVDMD of silages. Wilting increased the DM, NDF and lignin values and reduced the concentrations of CP, IVDMD and N-NH3. Based on our results, citrus pulp addition improves the chemical composition of elephant grass silage and increases its in vitro dry matter digestibility

From Victims of Trafficking to Freedom Fighters: Rethinking Migrant Domestic Workers in the Middle East

Throughout the Middle East migrant women are employed to work in people’s homes. While some experience good working relations with employers, others experience forms of abuse and labour coercion. This chapter evaluates critically different ways that system of unfree labour has been variously described and analysed as a form of ‘contract slavery’, ‘debt bondage’ and ‘trafficking’. It also shows how migrant women who describe themselves as ‘freelancers’ exit their original employer’s home both to escape that relation and in hopes of securing a better situation outside of the regular system of employment. Freelancing is more than simply a form of resistance. Rather, women who work as freelance migrant domestic workers challenge directly that state enforced control over their mobility and are on the vanguard of those migrants who are seeking through their own actions to effect social change

Dermatological patients with itch report more stress, stigmatization experience, anxiety and depression compared to patients without itch: Results from a European multi‐centre study

Background: Itch as the most common symptom in dermatology has been shown to be related to psychological factors such as stress, anxiety and depression. Moreover, associations were found between perceived stigmatization and itch. However, studies investigating the differences between patients with dermatoses with and without itch regarding perceived stress, stigmatization, anxiety and depression are missing. Therefore, one of the aims of the second study of the European Society for Dermatology and Psychiatry (ESDaP study II) was to investigate these relationships in a large cohort of patients with different itchy dermatoses. Results: 3399 patients with 14 different itchy dermatoses were recruited at 22 centres in 17 European countries. They filled in questionnaires to assess perceived stigmatization, stress, signs of clinically relevant anxiety or depression, itch‐related quality of life, the overall health status, itch duration, frequency and intensity. The most significant association between the severity of itching and the perception of stress was observed among individuals with rosacea (correlation coefficient r = 0.314). Similarly, the strongest links between itch intensity and experiences of stigmatization, anxiety, and depression were found in patients with seborrheic dermatitis (correlation coefficients r = 0.317, r = 0.356, and r = 0.400, respectively). Utilizing a stepwise linear regression analysis, it was determined that within the entire patient cohort, 9.3% of the variation in itch intensity could be accounted for by factors including gender, levels of anxiety, depression, and perceived stigmatization. Females and individuals with elevated anxiety, depression, and perceived stigmatization scores reported more pronounced itch intensities compared to those with contrary attributes. Conclusion: This study underscores the connection between experiencing itch and its intensity and the psychological strain it places on individuals. Consequently, psychological interventions should encompass both addressing the itch itself and the interconnected psychological factors. In specific cases, it becomes imperative for dermatologists to direct individuals towards suitable healthcare resources to undergo further psychological assessment

Isosorbide Mononitrate and Cilostazol Treatment in Patients With Symptomatic Cerebral Small Vessel Disease: The Lacunar Intervention Trial-2 (LACI-2) Randomized Clinical Trial

Importance Cerebral small vessel disease (cSVD) is a common cause of stroke (lacunar stroke), is the most common cause of vascular cognitive impairment, and impairs mobility and mood but has no specific treatment.Objective To test the feasibility, drug tolerability, safety, and effects of 1-year isosorbide mononitrate (ISMN) and cilostazol treatment on vascular, functional, and cognitive outcomes in patients with lacunar stroke.Design, Setting, and Participants The Lacunar Intervention Trial-2 (LACI-2) was an investigator-initiated, open-label, blinded end-point, randomized clinical trial with a 2 × 2 factorial design. The trial aimed to recruit 400 participants from 26 UK hospital stroke centers between February 5, 2018, and May 31, 2021, with 12-month follow-up. Included participants had clinical lacunar ischemic stroke, were independent, were aged older than 30 years, had compatible brain imaging findings, had capacity to consent, and had no contraindications to (or indications for) the study drugs. Data analysis was performed on August 12, 2022.Interventions All patients received guideline stroke prevention treatment and were randomized to ISMN (40-60 mg/d), cilostazol (200 mg/d), ISMN-cilostazol (40-60 and 200 mg/d, respectively), or no study drug.Main Outcomes The primary outcome was recruitment feasibility, including retention at 12 months. Secondary outcomes were safety (death), efficacy (composite of vascular events, dependence, cognition, and death), drug adherence, tolerability, recurrent stroke, dependence, cognitive impairment, quality of life (QOL), and hemorrhage.Results Of the 400 participants planned for this trial, 363 (90.8%) were recruited. Their median age was 64 (IQR, 56.0-72.0) years; 251 (69.1%) were men. The median time between stroke and randomization was 79 (IQR, 27.0-244.0) days. A total of 358 patients (98.6%) were retained in the study at 12 months, with 257 of 272 (94.5%) taking 50% or more of the allocated drug. Compared with those participants not receiving that particular drug, neither ISMN (adjusted hazard ratio [aHR], 0.80 [95% CI, 0.59 to 1.09]; P = .16) nor cilostazol (aHR, 0.77 [95% CI, 0.57 to 1.05]; P = .10) alone reduced the composite outcome in 297 patients. Isosorbide mononitrate reduced recurrent stroke in 353 patients (adjusted odds ratio [aOR], 0.23 [95% CI, 0.07 to 0.74]; P = .01) and cognitive impairment in 308 patients (aOR, 0.55 [95% CI, 0.36 to 0.86]; P = .008). Cilostazol reduced dependence in 320 patients (aHR, 0.31 [95% CI, 0.14 to 0.72]; P = .006). Combination ISMN-cilostazol reduced the composite (aHR, 0.58 [95% CI, 0.36 to 0.92]; P = .02), dependence (aOR, 0.14 [95% CI, 0.03 to 0.59]; P = .008), and any cognitive impairment (aOR, 0.44 [95% CI, 0.23 to 0.85]; P = .02) and improved QOL (adjusted mean difference, 0.10 [95% CI, 0.03 to 0.17]; P = .005) in 153 patients. There were no safety concerns.Conclusions and Relevance These results show that the LACI-2 trial was feasible and ISMN and cilostazol were well tolerated and safe. These agents may reduce recurrent stroke, dependence, and cognitive impairment after lacunar stroke, and they could prevent other adverse outcomes in cSVD. Therefore, both agents should be tested in large phase 3 trials.Trial Registration ClinicalTrials.gov Identifier: NCT0345159

Behavior of cracked steel plates strengthened with adhesively bonded CFRP laminates under fatigue Loading: Experimental and analytical study

The strengthening of steel structures using externally bonded (EB) carbon fiber-reinforced polymer (CFRP) laminates has gained popularity due to the advantages such as their high strength-to-weight ratio and corrosion resistance. Even though previous studies showed the application of EB CFRP laminates can enhance the fatigue performance of cracked steel plates, little is known regarding the high-cycle fatigue performance of CFRP-to-steel bonded joints. As debonding of the CFRP laminate from the steel substrate is a commonly observed failure mode under fatigue loading, a sound understanding of the behavior of CFRP-to-steel bonded joints is crucial for a better understanding of the behavior of CFRP-strengthened cracked steel plates under fatigue loading. This study experimentally and theoretically investigates the fatigue performance of CFRP-strengthened cracked steel plates. Five pre-cracked steel plates were strengthened with CFRP laminates and tested under fatigue loading. The test results for the failure modes, the fatigue-life extension, and the behavior of the CFRP-to-steel bonded joint were discussed. A numerical modeling approach based on a recently developed bond-slip model for the behavior of the CFRP-to-steel bonded interface under fatigue loading is presented for modeling the behavior of the CFRP-strengthened cracked steel plate. Although the proposed theoretical model is conservative, this method accurately predicted the remaining fatigue life of CFRP-strengthened cracked steel plates.ISSN:0263-8223ISSN:1879-108

Elazığ Bölgesinde Mental Retardasyonlu Çocuklarda Sitogenetik İncelemeler

Frajil-X sendromu insanlarda kalıtsal zeka geriliğinin en sık nedenidir. Kalıtsal ve kalıtsal olmayan mental retardasyon (MR) nedenleri dikkate alındığında Down sendromundan sonra ikinci sırada gelmektedir. Bu çalışmanın amacı, MR ve konuşma güçlüğü bozukluğu olan vakalarda sitogenetik analizlerle diğer kromozomal anormallikler ve FRXS’unun insidansını ortaya koymaktır. Frajil-X tanısı sitogenetik olarak folattan fakir besiyeri kullanılarak elde edilen lenfosit kültürlerindeki metafaz kromozomları inceleyerek konulmaktadır. Bu çalışmada laboratuvarımıza Frajil-X açısından sitogenetik araştırma için yollanan MR’lu 72 olgu çalışıldı. Olguların hepsinde hem standart yöntemlerle hem de Frajil-X için folattan fakir besiyeri ile elde edilen metafazlarda kromozomlar değerlendirildi. Frajil-X için her olguda en az 100 metafaz değerlendirildi. 72 olgunun büyük bir çoğunluğu Fırat Üniversitesi Tıp Merkezi Nöroloji Anabilim Dalında değerlendirmeden geçmişti. Geliş yakınmaları içinde ilk iki sırayı MR ve konuşma güçlüğü alıyordu. Tüm olgular (72 olgu) içinde sitogenetik olarak 7 olguda (%9.5) FrajilX tanısı konuldu. Sonuç olarak, Frajil-X sıklığı MR’lu topluluklarda yapılan frajil tarama çalışmaları sonucu ile uygunluk gösterdi. Olguların sitogenetik çalışmaya alınmadan önce iyi bir klinik seçimden geçmelerinin uygun olacağı kanısına varıldı