Multi-objective sustainability optimization of CCHP systems considering the discreteness of equipment capabilities

The value of waste heat had led to an extensive study on Combined Cooling, Heating and Power (CCHP) system in recent decades, but the following three research gaps still need to be tackled to achieve a better economic and environmental performance. Firstly, the complete discreteness of equipment capabilities had not been considered. It means that multiple units with different capacities cannot be selected for a type of equipment. Then, the ambiguity and subjectivity existing in decision-makers/stakeholders’ judgments on the importance of objectives are usually ignored. Finally, an easily understood and comprehensive environmental indicator based on life cycle perspective for system optimization had not been established. Thus, the aim of this study is to establish a mathematical framework to help the stakeholders select the optimal configurations, capacities, and operation conditions of CCHP system while narrowing the above three research gaps to avoid the sub-optimal solutions. Subsequently, a hypothetical case was used to verify the validity of the proposed model, along with analysis of system performance. The results indicate that the CCHP system is superior to the conventional systems, and the proposed mathematical model in this paper can improve the performance of CCHP system in terms of economy, environment, and energy

On the Security Risks of Knowledge Graph Reasoning

Knowledge graph reasoning (KGR) -- answering complex logical queries over large knowledge graphs -- represents an important artificial intelligence task, entailing a range of applications (e.g., cyber threat hunting). However, despite its surging popularity, the potential security risks of KGR are largely unexplored, which is concerning, given the increasing use of such capability in security-critical domains. This work represents a solid initial step towards bridging the striking gap. We systematize the security threats to KGR according to the adversary's objectives, knowledge, and attack vectors. Further, we present ROAR, a new class of attacks that instantiate a variety of such threats. Through empirical evaluation in representative use cases (e.g., medical decision support, cyber threat hunting, and commonsense reasoning), we demonstrate that ROAR is highly effective to mislead KGR to suggest pre-defined answers for target queries, yet with negligible impact on non-target ones. Finally, we explore potential countermeasures against ROAR, including filtering of potentially poisoning knowledge and training with adversarially augmented queries, which leads to several promising research directions.Comment: In proceedings of USENIX Security'23. Codes: https://github.com/HarrialX/security-risk-KG-reasonin

Glass-ceramic Optical Fiber Containing Ba2 TiSi2O8 Nanocrystals for Frequency Conversion of Lasers

A glass-ceramic optical fiber containing Ba2TiSi2O8 nanocrystals fabricated using a novel combination of the melt-in-tube method and successive heat treatment is reported for the first time. For the melt-in-tube method, fibers act as a precursor at the drawing temperature for which the cladding glass is softened while the core glass is melted. It is demonstrated experimentally that following heat treatment, Ba2TiSi2O8 nanocrystals with diameters below 10 nm are evenly distributed throughout the fiber core. Comparing to the conventional rod-in-tube method, the melt-in-tube method is superior in terms of controllability of crystallization to allow for the fabrication of low loss glass-ceramic fibers. When irradiated using a 1030 nm femtosecond laser, an enhanced green emission at a wavelength of 515 nm is observed in the glass-ceramic fiber, which demonstrates second harmonic generation of a laser action in the fabricated glass-ceramic fibers. Therefore, this new glass-ceramic fiber not only provides a highly promising development for frequency conversion of lasers in all optical fiber based networks, but the melt-in-tube fabrication method also offers excellent opportunities for fabricating a wide range of novel glass-ceramic optical fibers for multiple future applications including fiber telecommunications and lasers

Developing a class of dual atom materials for multifunctional catalytic reactions

Dual atom catalysts, bridging single atom and metal/alloy nanoparticle catalysts, offer more opportunities to enhance the kinetics and multifunctional performance of oxygen reduction/evolution and hydrogen evolution reactions. However, the rational design of efficient multifunctional dual atom catalysts remains a blind area and is challenging. In this study, we achieved controllable regulation from Co nanoparticles to CoN4 single atoms to Co2N5 dual atoms using an atomization and sintering strategy via an N-stripping and thermal-migrating process. More importantly, this strategy could be extended to the fabrication of 22 distinct dual atom catalysts. In particular, the Co2N5 dual atom with tailored spin states could achieve ideally balanced adsorption/desorption of intermediates, thus realizing superior multifunctional activity. In addition, it endows Zn-air batteries with long-term stability for 800 h, allows water splitting to continuously operate for 1000 h, and can enable solar-powered water splitting systems with uninterrupted large-scale hydrogen production throughout day and night. This universal and scalable strategy provides opportunities for the controlled design of efficient multifunctional dual atom catalysts in energy conversion technologies

Ceftazidime-avibactam induced renal disorders: past and present

With the increasing prevalence of multidrug-resistant Gram-negative bacterial pathogens worldwide, antimicrobial resistance has become a significant public health concern. Ceftazidime-avibactam (CAZ-AVI) exhibited excellent in vitro activity against many carbapenemase-producing pathogens, and was widely used for the treatment of various complicated infections. CAZ-AVI is well tolerated across all dosing regimens, and its associated acute kidney injury (AKI) in phase II/III clinical trials is rare. However, recent real-world studies have demonstrated that CAZ-AVI associated AKI was more frequent in real-world than in phase II and III clinical trials, particularly in patients receiving concomitant nephrotoxic agents, with critically ill patients being at a higher risk. Herein, we reviewed the safety data related to renal impairment of CAZ-AVI, and discussed its pharmacokinetic/pharmacodynamic targets and dosage adjustment in patients with impaired renal function. This review aimed to emphasize the importance for healthcare professionals to be aware of this adverse event of CAZ-AVI and provide practical insights into the dosage optimization in critically ill patients with renal dysfunction

Supplementation of Vitamin E Protects Chickens from Newcastle Disease Virus-Mediated Exacerbation of Intestinal Oxidative Stress and Tissue Damage

BACKGROUND/AIMS: Newcastle disease virus (NDV) causes a highly devastating and contagious disease in poultry, which is mainly attributed to extensive tissue damages in the digestive, respiratory and nervous systems. However, nature and dynamics of NDV-induced oxidative stresses in the intestine of chickens remain elusive. METHODS: In this study, we examined the magnitude of intestinal oxidative stress and histopathological changes caused by the virulent NDV infection, and explored the protective roles of vitamin E (vit. E) in ameliorating these pathological changes. For these purposes, chickens were divided into four groups namely i) non supplemented and non-challenged (negative control, CON); ii) no supplementation of vit. E but challenged with ZJ1 (positive control, NS+CHA); iii) vit. E supplementation at the dose of 50 IU/day/Kg body weight and ZJ1 challenge (VE50+CHA); and 4) vit. E supplementation at the dose of 100 IU/day/Kg body weight and ZJ1 challenge (VE100+CHA). In all groups, we analyzed concentrations of glutathione (GSH), malondialdehyde (MDA), nitric oxide (NO), total antioxidant capacity (T-AOC), and activity of glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) using biochemical methods. The virus loads were determined by quantitative RT-PCR and antibody titers by hemagglutination inhibition assays. We also examined the histopathological changes in the duodenal and jejunal mucosa at 3 and 5-day post infection (dpi) with NDV. RESULTS: A significant elevation in the NO level was observed in NDV challenged chickens compared to the CON chickens at 2 dpi. The MDA contents were significantly increased whereas GSH was significantly decreased in NDV-challenged chickens compared to control. Furthermore, activities of GST, CAT, SOD, as well as the TOAC were markedly decreased in challenged chickens in comparison with control. Virus copy numbers were higher in NDV infected NS+CHA group compared to other groups. Severe histopathological changes including inflammation, degeneration and broken villi were observed in the intestine of NDV challenged chickens. However, all these malfunctions of antioxidant system and pathological changes in the intestine were partially or completely reversed by the vit. E supplementation. CONCLUSIONS: Our results suggest that NDV infection causes oxidative stress and histopathological changes in the duodenum and jejunum of chickens, which can be partially or fully ameliorated by supplementation of vit. E. Additionally, these findings suggest that oxidative stress contributes to the intestinal damages in NDV infected chickens. These findings will help to understand the pathogenesis of NDV and further investigation of therapeutic agents for control of Newcastle disease

Production, characterization, and epitope mapping of a monoclonal antibody against genotype VII Newcastle disease virus V protein

Newcastle disease virus (NDV) V protein is crucial for viral interferon (IFN) antagonism and virulence, determining its host range restriction. However, little information is available on the B cell epitopes of V protein and the subcellular movement of V protein in the process of NDV infection. In this study, the monoclonal antibody (mAb) clone 3D7 against genotype VII NDV V protein was generated by immunizing mice with a purified recombinant His-tagged carboxyl-terminal domain (CTD) region of V protein. Fine epitope mapping analysis and B-cell epitope prediction indicated that mAb 3D7 recognized a linear epitope 152RGPAELWK159, which is located in the V protein CTD region. Sequence alignment showed that the mAb clone 3D7-recognized epitope is highly conserved among Class II genotype VII NDV strains, but not among other genotypes, suggesting it could serve as a genetic marker to differentiate NDV genotypes. Furthermore, the movement of V protein during NDV replication in infected cells were determined by using this mAb. It was found that V protein localized around the nucleus during virus replication. The establishment of V protein-specific mAb and identification of its epitope extend our understanding of the antigenic characteristics of V protein and provide a basis for the development of epitope-based diagnostic assays

Prosedur penyelesaian pembiayaan bermasalah pada akad mudharabah dalam rangka meminimalisir resiko di BMT Amanah Usaha Mulia Magelang

Permasalah kehidupan perekonomian yang sulit, membuat masyarakat berinisiatif untuk membuka usaha sendiri. Mereka membutuhkan suatu bantuan berupa dana untuk memperlancar usahanya, maka BMT Amanah Usaha Mulia Magelang ikut untuk mengembangkan produknya yaitu pembiayaan mudharabah sesuai perkembangan dunia perbankan dalam target peningkatan keuntungan dan menyejahterakan masyarakat. Dengan diberikanya pembiayaan tersebut, terkadang muncul adanya pembiayaan bermasalah dikarenakan ada beberapa faktor diantaranya ketidakmampuan anggota untuk membayar tepat waktu atau jatuh tempo pembayaran diakibatkan karena usaha anggota yang kurang lancar dan lain sebagaianya. Tugas Akhir ini berjudul “ Prosedur Penyelesaian Pembiayaan Bermasalah pada Akad Mudharabah Dalam Rangka Meminimalisir Risiko” Berdasarkan judul tersebut dapat diambil rumusan masalah yaitu apa penyebab terjadinya pembiayaan bermasalah pada BMT Amanah Usaha Mulia Magelang dan bagaimana prosedur penyelesaian pembiayaaan bermasalah pada akad mudharabah di BMT Amanah Usaha Mulia Magelang. Penelitian ini merupakan penelitian lapangan dimana sumber data yang digunakan berasal dari data primer dan sekunder yang diperoleh melalui metode wawancara dengan manajer, bagian pembiayaan dan dokumentasi. Metode yang digunakan dalam penelitian ini adalah deskriptif kualitatif yang bertujuan untuk menggambarkan secara sistematis dan akurat mengenai objek penelitian. Berdasarkan hasil penelitian dapat disimpulkan bahwa penyebab terjadinya pembiayaan bermasalah yaitu faktor internal meliputi kurang telitinya petugas BMT dalam menganalisi data calon anggota, kurang disiplinya dalam penagihan dan eksternal meliputi karakter anggota yang kurang baik, usahanya bangkrut dan terjadinya bencana alam yang tidak terduga. Adapun prosesdur yang digunakan BMT Amanah Usaha Mulia dalam menyelesaian pembiayaan bermasalah pada akad mudharabah dengan cara kekeluargaan atau musyawarah dengan anggota, penjadwalan kembali (rescheduling), persyaratan kembali (reconditioning), pengambilan jaminan (eksekusi), dan write off final. Di BMT Amanah Usaha Mulia dalam penyelesaian pembiayaan bermasalah jarang menngunakan jalur hukum, tetapi sering menggunakan cara kekeluargaan yang dianggap lebih efektif dan eksekusi jaminan apabila anggota tersebut sudah mengalami macet atau bermasalah

Low-Temperature Selective Catalytic Reduction DeNOX and Regeneration of Mn–Cu Catalyst Supported by Activated Coke

The activated coke is a promising support for catalysts, and it is important to study the performance of the activated coke catalyst on the removal of NOx. In the current research, a series of the activated coke-supported Mn–Cu catalysts are prepared by the incipient wetness impregnation method. The effects of the molar ration of Mn/Cu, the content of Mn–Cu, the calcination temperature, and reaction space velocity on NO conversion are investigated, and it was found that the 8 wt.% Mn0.7Cu0.3/AC had the best catalytic activity when the calcination temperature was 200 °C. The existence of SO2 caused the catalyst to deactivate, but the activity of the poisoning catalyst could be recovered by different regeneration methods. To uncover the underlying mechanism, BET, XPS, XRD, SEM and FTIR characterizations were performed. These results suggested that the specific surface area and total pore volume of the poisoning catalyst are recovered and the sulfite and sulfate on the surface of the poisoning catalysts are removed after water washing regeneration. More importantly, the water washing regeneration returns the value of Mn3+/Mn4+, Cu2+/Cu+, and Oα/Oβ, related to the activity, basically back to the level of the fresh catalyst. Thus, the effect of water washing regeneration is better than thermal regeneration. These results could provide some helpful information for the design and development of the SCR catalysts

Solute concentrations and stresses in nanograined H-Pd solid solution

In the present work, we applied the Gibbs-approach-based adsorption isotherm for nanograined polycrystals to H-Pd solid solutions. Using the published experimental data of lattice strain and sample strain of the nanograined Pd, with an average grain size of 10 nm and in thermodynamic equilibrium with an H-2 partial pressure, we determined H concentrations and stresses, as a function of the H-2 partial pressure, in both grains and grain boundaries. More importantly, we determined the intrinsic properties of grain boundaries, such as the grain boundary bulk modulus, the grain boundary excess thickness, and the difference in chemical potential between grains and grain boundaries. With the determined intrinsic properties, the Gibbs-approach-based adsorption isotherm predicted the segregation of H in grain boundaries of nanograined Pd with an average grain size of 5 nm. The predication was verified by other reported experimental data. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved