On the Verification of Deep Reinforcement Learning Solution for Intelligent Operation of Distribution Grids

Capabilities of deep reinforcement learning (DRL) in obtaining fast decision policies in high dimensional and stochastic environments have led to its extensive use in operational research, including the operation of distribution grids with high penetration of distributed energy resources (DER). However, the feasibility and robustness of DRL solutions are not guaranteed for the system operator, and hence, those solutions may be of limited practical value. This paper proposes an analytical method to find feasibility ellipsoids that represent the range of multi-dimensional system states in which the DRL solution is guaranteed to be feasible. Empirical studies and stochastic sampling determine the ratio of the discovered to the actual feasible space as a function of the sample size. In addition, the performance of logarithmic, linear, and exponential penalization of infeasibility during the DRL training are studied and compared in order to reduce the number of infeasible solutions

Hierarchical Flexibility Offering Strategy for Integrated Hybrid Resources in Real-time Energy Markets

This paper proposes a hierarchical model for determining the energy flexibility offering strategy of integrated hybrid resources (IHRs) in power distribution systems to participate in real-time energy markets. The proposed model utilizes the scalability, fast response time, and uncertainty observation of deep reinforcement learning (DRL) to overcome the scalability issue of operating numerous flexible resources and deliverability of energy flexibility to the real-time markets in the presence of the network constraints. To that end, the power distribution system is divided into multiple IHRs, where different types of flexible loads, energy storage systems, and solar plants with controllable inverters are operated through local IHR controllers, trained by deep deterministic policy gradient (DDPG) algorithm. Active power request and reactive power capacity of IHRs are then transmitted to a central flexibility controller, where a quadratic optimization model ensures the deliverability of the energy flexibility to the real-time energy market by satisfying the distribution network constraints. The proposed model is implemented on the 123-bus test power distribution system, demonstrating the capability of DRL-based hierarchical model for scalable operation of IHRs in order to offer deliverable energy flexibility to the real-time energy market

A Didactic Approach to Curriculum Renewal on the Basis of Market Demands: A Grounded Theory Study

This study aims to provide sufficient information on the issues of the current approaches, materials, and curricula employed in the field of Translation Studies. To do so, the researcher investigated the demands of the market and the vocational realities so as to come to an understanding of the curriculum drawbacks. Furthermore, this study provides a review on the current trends used by academic institutions and private sector inIran. As a phase of the adopted model, several semi-structured interviews were held with authorities in the market of translation, and then the gathered data. Having analyzed the data, a number of themes emerged, the most important of which were the skills pertinent to technology and computer assisted translation. Finally, a number of recommendations were made to improve the official curriculum of Translation Studies. To the future researchers, this study provides baseline information on the recent status of translator teaching trends

Effects of repeated intravitreal bevacizumab administration on anterior segment parameters and limbal stem cells

Background: Macular edema (ME) is fluid accumulation in the macula caused by vascular leakage. Repeated intravitreal bevacizumab (IVB) injections are extensively used to treat ME of different origins, are well tolerated, and have few side effects. This study evaluated the effects of repeated IVB injections on the anterior segment parameters and limbal stem cells (LSCs) in eyes with ME. Methods: This before–after study involved patients with ME of different causes who underwent repeated IVB injections at the Imam Khomeini Ophthalmology Center in Kermanshah, Iran. Before and after repeated IVB injections, anterior segment parameters were measured using anterior segment optical coherence tomography, and the LSCs were assessed using impression cytology. Results: We enrolled 42 eyes of 42 patients with a mean (standard deviation [SD]) age of 59.6 (7.6) years, of whom 25 (59.5%) were men and 17 (40.5%) were women. The underlying diseases included diabetic ME in 30 eyes (71.4%), central (5 [11.9%]) or branch (3 [7.1%]) retinal vein occlusion, and choroidal neovascularization in 4 eyes (9.5%). The right eye was affected in 22 (52.4%) participants. The mean (SD) number of IVB injections was 4.3 (1.3). After repeated injections, the mean central corneal thickness (CCT) increased, whereas the mean anterior chamber angle (ACA) and anterior chamber depth (ACD) decreased (all P<0.001). Three patients developed LSC deficiency after repeated IVB injections for diabetic ME. Conclusions: We observed a significant increase in the mean CCT and a decrease in the mean ACA and ACD after repeated IVB injections in our series. Three patients developed LSC deficiency after repeated IVB injections for diabetic ME management. The observed effect on LSC may cast doubt on the safety of repeated IVB injections; however, this finding must be verified in multicenter clinical trials with longer follow-up periods and larger study samples

Improved PET imaging of uPAR expression using new (64)Cu-labeled cross-bridged peptide ligands:comparative in vitro and in vivo studies

The correlation between uPAR expression, cancer cell invasion and metastases is now well-established and has prompted the development of a number of uPAR PET imaging agents, which could potentially identify cancer patients with invasive and metastatic lesions. In the present study, we synthesized and characterized two new cross-bridged (64)Cu-labeled peptide conjugates for PET imaging of uPAR and performed a head-to-head comparison with the corresponding and more conventionally used DOTA conjugate. Based on in-source laser-induced reduction of chelated Cu(II) to Cu(I), we now demonstrate the following ranking with respect to the chemical inertness of their complexed Cu ions: DOTA-AE105 << CB-TE2A-AE105 < CB-TE2A-PA-AE105, which is correlated to their corresponding demetallation rate. No penalty in the uPAR receptor binding affinity of the targeting peptide was encountered by conjugation to either of the macrobicyclic chelators (IC(50) ~ 5-10 nM) and high yields and radiochemical purities (>95%) were achieved in all cases by incubation at 95ºC. In vivo, they display identical tumor uptake after 1h, but differ significantly after 22 hrs, where the DOTA-AE105 uptake remains surprisingly high. Importantly, the more stable of the new uPAR PET tracers, (64)Cu-CB-TE2A-PA-AE105, exhibits a significantly reduced liver uptake compared to (64)Cu-DOTA-AE105 as well as (64)Cu-CB-TE2A-AE105, (p<0.0001), emphasizing that our new in vitro stability measurements by mass spectrometry predicts in vivo stability in mice. Specificity of the best performing ligand, (64)Cu-CB-TE2A-PA-AE105 was finally confirmed in vivo using a non-binding (64)Cu-labeled peptide as control ((64)Cu-CB-TE2A-PA-AE105(mut)). This control PET-tracer revealed significantly reduced tumor uptake (p<0.0001), but identical hepatic uptake compared to its active counterpart ((64)Cu-CB-TE2A-PA-AE105) after 1h. In conclusion, our new approach using in-source laser-induced reduction of Cu(II)-chelated PET-ligands provides useful information, which are predictive for the tracer stability in vivo in mice. Furthermore, the increased stability of our new macrobicyclic (64)Cu-CB-TE2A-PA-AE105 PET ligand is paralleled by an excellent imaging contrast during non-invasive PET scanning of uPAR expression in preclinical mouse cancer models. The translational promises displayed by this PET-tracer for future clinical cancer patient management remains, however, to be investigated

Effects of Topical 1% Sodium Hyaluronate and Hydroxypropyl Methylcellulose in Treatment of Corneal Epithelial Defects

We aimed to compare the therapeutic effects of topical 1% sodium hyaluronate (Healon) or hydroxypropyl methylcellulose (HPMC) for the treatment of alkali-induced epithelial corneal defects. An alkali burn was produced in 30 corneas of 30 New Zealand White rabbits, using a 7.5-mm-diameter trephine. The rabbits were randomly divided into three groups. Four times a day, one group was treated with 1% sodium hyaluronate, one with HPMC, and one (the control group) with physiologic saline. During the treatment period, the size of the epithelial defect was observed every day, up to day 17, using a slit-lamp biomicroscope (with fluorescein). Sodium hyaluronate significantly accelerated the wound healing process compared with saline and increased the healing rate to an even greater extent compared with HPMC. Sodium hyaluronate, but not HPMC, is an effective wound-healing adjuvant for alkali-induced corneal epithelial defects.Â

Validity and Reliability of Bariatric Surgery Self- Management Behaviors Questionnaire in Iranian Population

Background: Bariatric surgery is the most effective intervention for treatment of severe obesity and patient’s adherence to self management behaviors are essential to reduce complications after surgery. The purpose of this study was to investigate the validity and reliability of bariatric surgery self-management behaviors questionnaire (BSSQ) in Iranian population. Methods: From December 2016 till June 2016, all obese patients who underwent laparoscopic obesity surgery in Shiraz Ghadir Mother and Child Hospitalwere were enrolled. Their demographic characteristics, BSSQ, General Adherence Scale (GAS), and the Specific Adherence Scale (SAS) questionnaires were collected. The content, structural and simultaneous validity and factor analysis were determined using GAS and SAS questionnaires. Results: According to psychometric factors including eating behaviors, fluid intake, vitamin and mineral supplement intake, fruits, vegetables, whole grain and protein intake, physical activity and dumping syndrome management, 6 factors could explain 61.5% of BSSQ. Total score of correlation matrix BSSQ with GAS and SAS were 0.36 and 0.70. For reliability, the Cronbach’s alpha coefficient was found 0.90 and Guttmann split-half coefficient was 0.78. Conclusion: BSSQ was shown to have an acceptable validity and reliability to be used for assessing the bariatric surgery self-management behaviors in Iranian population

A cyclic peptidic serine protease inhibitor:increasing affinity by increasing peptide flexibility

Peptides are attracting increasing interest as protease inhibitors. Here, we demonstrate a new inhibitory mechanism and a new type of exosite interactions for a phage-displayed peptide library-derived competitive inhibitor, mupain-1 (CPAYSRYLDC), of the serine protease murine urokinase-type plasminogen activator (uPA). We used X-ray crystal structure analysis, site-directed mutagenesis, liquid state NMR, surface plasmon resonance analysis, and isothermal titration calorimetry and wild type and engineered variants of murine and human uPA. We demonstrate that Arg6 inserts into the S1 specificity pocket, its carbonyl group aligning improperly relative to Ser195 and the oxyanion hole, explaining why the peptide is an inhibitor rather than a substrate. Substitution of the P1 Arg with novel unnatural Arg analogues with aliphatic or aromatic ring structures led to an increased affinity, depending on changes in both P1 - S1 and exosite interactions. Site-directed mutagenesis showed that exosite interactions, while still supporting high affinity binding, differed substantially between different uPA variants. Surprisingly, high affinity binding was facilitated by Ala-substitution of Asp9 of the peptide, in spite of a less favorable binding entropy and loss of a polar interaction. We conclude that increased flexibility of the peptide allows more favorable exosite interactions, which, in combination with the use of novel Arg analogues as P1 residues, can be used to manipulate the affinity and specificity of this peptidic inhibitor, a concept different from conventional attempts at improving inhibitor affinity by reducing the entropic burden

Global, regional, and national burden of chronic kidney disease, 1990–2017 : a systematic analysis for the Global Burden of Disease Study 2017

Background Health system planning requires careful assessment of chronic kidney disease (CKD) epidemiology, but data for morbidity and mortality of this disease are scarce or non-existent in many countries. We estimated the global, regional, and national burden of CKD, as well as the burden of cardiovascular disease and gout attributable to impaired kidney function, for the Global Burden of Diseases, Injuries, and Risk Factors Study 2017. We use the term CKD to refer to the morbidity and mortality that can be directly attributed to all stages of CKD, and we use the term impaired kidney function to refer to the additional risk of CKD from cardiovascular disease and gout. Methods The main data sources we used were published literature, vital registration systems, end-stage kidney disease registries, and household surveys. Estimates of CKD burden were produced using a Cause of Death Ensemble model and a Bayesian meta-regression analytical tool, and included incidence, prevalence, years lived with disability, mortality, years of life lost, and disability-adjusted life-years (DALYs). A comparative risk assessment approach was used to estimate the proportion of cardiovascular diseases and gout burden attributable to impaired kidney function. Findings Globally, in 2017, 1·2 million (95% uncertainty interval [UI] 1·2 to 1·3) people died from CKD. The global all-age mortality rate from CKD increased 41·5% (95% UI 35·2 to 46·5) between 1990 and 2017, although there was no significant change in the age-standardised mortality rate (2·8%, −1·5 to 6·3). In 2017, 697·5 million (95% UI 649·2 to 752·0) cases of all-stage CKD were recorded, for a global prevalence of 9·1% (8·5 to 9·8). The global all-age prevalence of CKD increased 29·3% (95% UI 26·4 to 32·6) since 1990, whereas the age-standardised prevalence remained stable (1·2%, −1·1 to 3·5). CKD resulted in 35·8 million (95% UI 33·7 to 38·0) DALYs in 2017, with diabetic nephropathy accounting for almost a third of DALYs. Most of the burden of CKD was concentrated in the three lowest quintiles of Socio-demographic Index (SDI). In several regions, particularly Oceania, sub-Saharan Africa, and Latin America, the burden of CKD was much higher than expected for the level of development, whereas the disease burden in western, eastern, and central sub-Saharan Africa, east Asia, south Asia, central and eastern Europe, Australasia, and western Europe was lower than expected. 1·4 million (95% UI 1·2 to 1·6) cardiovascular disease-related deaths and 25·3 million (22·2 to 28·9) cardiovascular disease DALYs were attributable to impaired kidney function. Interpretation Kidney disease has a major effect on global health, both as a direct cause of global morbidity and mortality and as an important risk factor for cardiovascular disease. CKD is largely preventable and treatable and deserves greater attention in global health policy decision making, particularly in locations with low and middle SDI