scholarly journals Halides as versatile anions in asymmetric anion-binding organocatalysis

2021 ◽  
Vol 17 ◽  
pp. 2270-2286
Author(s):  
Lukas Schifferer ◽  
Martin Stinglhamer ◽  
Kirandeep Kaur ◽  
Olga García Macheño

This review intends to provide an overview on the role of halide anions in the development of the research area of asymmetric anion-binding organocatalysis. Key early elucidation studies with chloride as counter-anion confirmed this type of alternative activation, which was then exploited in several processes and contributed to the advance and consolidation of anion-binding catalysis as a field. Thus, the use of the halide in the catalyst–anion complex as both a mere counter-anion spectator or an active nucleophile has been depicted, along with the new trends toward additional noncovalent contacts within the HB-donor catalyst and supramolecular interactions to both the anion and the cationic reactive species.

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 999 ◽  
Author(s):  
Aranza Denisse Vital-Grappin ◽  
Maria Camila Ariza-Tarazona ◽  
Valeria Montserrat Luna-Hernández ◽  
Juan Francisco Villarreal-Chiu ◽  
Juan Manuel Hernández-López ◽  
...  

Microplastics (MPs) are distributed in a wide range of aquatic and terrestrial ecosystems throughout the planet. They are known to adsorb hazardous substances and can transfer them across the trophic web. To eliminate MPs pollution in an environmentally friendly process, we propose using a photocatalytic process that can easily be implemented in wastewater treatment plants (WWTPs). As photocatalysis involves the formation of reactive species such as holes (h+), electrons (e−), hydroxyl (OH●), and superoxide ion (O2●−) radicals, it is imperative to determine the role of those species in the degradation process to design an effective photocatalytic system. However, for MPs, this information is limited in the literature. Therefore, we present such reactive species’ role in the degradation of high-density polyethylene (HDPE) MPs using C,N-TiO2. Tert-butanol, isopropyl alcohol (IPA), Tiron, and Cu(NO3)2 were confirmed as adequate OH●, h+, O2●− and e− scavengers. These results revealed for the first time that the formation of free OH● through the pathways involving the photogenerated e− plays an essential role in the MPs’ degradation. Furthermore, the degradation behaviors observed when h+ and O2●− were removed from the reaction system suggest that these species can also perform the initiating step of degradation.


2021 ◽  
Vol 165 ◽  
pp. 54
Author(s):  
Patricia de la Cruz-Ojeda ◽  
M. Ángeles Rodríguez-Hernández ◽  
Elena Navarro-Villarán ◽  
Paloma Gallego ◽  
Pavla Staňková ◽  
...  

Systems ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 33
Author(s):  
Olena Klymenko ◽  
Lise Lillebrygfjeld Halse ◽  
Bjørn Jæger

Sustainability accounting is an emerging research area receiving growing awareness. This study examines the role of digital technology in manufacturing companies’ sustainability accounting. To guide the research, we use a triple layered business model canvas, which supports the accounting of a manufacturer’s performance for the economic, environmental, and social aspects of sustainability. We present an explorative case study of four Norwegian manufacturing companies representing different industries. The findings from the study indicate that while accounting for economic values is well taken care of, companies do not perform comprehensive environmental and social accounting. Furthermore, we observed a shift from a focus on sustainability issues related to the internal manufacturing process to a focus on sustainability issues for the life cycle of the product. Even though the manufacturers are at the forefront with regard to automation and control of production, with extensive use of robots giving a large amount of data, these data are not utilized towards sustainability accounting, showing that sustainability and digitalization are seen as two separate phenomena. This study sheds light on how digital data available from applied Industry 4.0 technologies could enhance sustainability accounting with limited efforts, linking sustainability and digitalization. The results provide insights for manufacturers and researchers in moving towards more sustainable operations and products.


2019 ◽  
Vol 35 (11) ◽  
pp. 1853-1861 ◽  
Author(s):  
Miriam Zacchia ◽  
Emanuela Marchese ◽  
Elena Martina Trani ◽  
Marianna Caterino ◽  
Giovanna Capolongo ◽  
...  

Abstract The primary cilium (PC) was considered as a vestigial organelle with no significant physiological importance, until the discovery that PC perturbation disturbs several signalling pathways and results in the dysfunction of a variety of organs. Genetic studies have demonstrated that mutations affecting PC proteins or its anchoring structure, the basal body, underlie a class of human disorders (known as ciliopathies) characterized by a constellation of clinical signs. Further investigations have demonstrated that the PC is involved in a broad range of biological processes, in both developing and mature tissues. Kidney disease is a common clinical feature of cilia disorders, supporting the hypothesis of a crucial role of the PC in kidney homoeostasis. Clinical proteomics and metabolomics are an expanding research area. Interestingly, the application of these methodologies to the analysis of urine, a biological sample that can be collected in a non-invasive fashion and possibly in large amounts, makes these studies feasible also in patients. The present article describes the most recent proteomic and metabolomic studies exploring kidney dysfunction in the setting of ciliopathies, showing the potential of these methodologies in the elucidation of disease pathophysiology and in the discovery of biomarkers.


Cancers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1160
Author(s):  
Giusi La Camera ◽  
Luca Gelsomino ◽  
Amanda Caruso ◽  
Salvatore Panza ◽  
Ines Barone ◽  
...  

Breast cancer is the most common solid malignancy diagnosed in females worldwide, and approximately 70% of these tumors express estrogen receptor α (ERα), the main biomarker of endocrine therapy. Unfortunately, despite the use of long-term anti-hormone adjuvant treatment, which has significantly reduced patient mortality, resistance to the endocrine treatments often develops, leading to disease recurrence and limiting clinical benefits. Emerging evidence indicates that extracellular vesicles (EVs), nanosized particles that are released by all cell types and responsible for local and systemic intercellular communications, might represent a newly identified mechanism underlying endocrine resistance. Unraveling the role of EVs, released by transformed cells during the tumor evolution under endocrine therapy, is still an open question in the cancer research area and the molecular mechanisms involved should be better defined to discover alternative therapeutic approaches to overcome resistance. In this review, we will provide an overview of recent findings on the involvement of EVs in sustaining hormonal resistance in breast cancer and discuss opportunities for their potential use as biomarkers to monitor the therapeutic response and disease progression.


Blood ◽  
1994 ◽  
Vol 84 (6) ◽  
pp. 1843-1850 ◽  
Author(s):  
E Arnaud ◽  
M Lafay ◽  
P Gaussem ◽  
V Picard ◽  
M Jandrot-Perrus ◽  
...  

Abstract An autoantibody, developed by a patient with severe and recurrent arterial thrombosis, was characterized to be directed against the anion- binding exosite of thrombin, and inhibited all thrombin interactions requiring this secondary binding site without interfering with the catalytic site. The effect of the antibody was studied on thrombin interactions with platelets and endothelial cells from human umbilical veins (HUVEC). The autoantibody specifically and concentration- dependently inhibited alpha-thrombin-induced platelet activation and prostacyclin (PGI2) synthesis from HUVEC. It had no effect when gamma- thrombin or the thrombin receptor activation peptide SFLLR were the inducers. The effect of the antibody on protein C activation has been studied. The antibody blocked the thrombin-thrombomodulin activation of protein C. The inhibition of the activation was maximal with a low concentration of thrombomodulin. The fact that the autoantibody inhibited concentration-dependent alpha-thrombin-induced platelet and endothelial cell functions emphasizes the crucial role of the anion- binding exosite of thrombin to activate its receptor. In regard to the pathology, the antibody inhibited two vascular processes implicated in thrombin-antithrombotic functions, PGI2 secretion, and protein C activation, which could be implicated in this arterial thrombotic disease.


Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1220
Author(s):  
Deyamira Matuz-Mares ◽  
Héctor Riveros-Rosas ◽  
María Magdalena Vilchis-Landeros ◽  
Héctor Vázquez-Meza

Cardiovascular diseases (CVD) (such as occlusion of the coronary arteries, hypertensive heart diseases and strokes) are diseases that generate thousands of patients with a high mortality rate worldwide. Many of these cardiovascular pathologies, during their development, generate a state of oxidative stress that leads to a deterioration in the patient’s conditions associated with the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). Within these reactive species we find superoxide anion (O2•–), hydroxyl radical (•OH), nitric oxide (NO•), as well as other species of non-free radicals such as hydrogen peroxide (H2O2), hypochlorous acid (HClO) and peroxynitrite (ONOO–). A molecule that actively participates in counteracting the oxidizing effect of reactive species is reduced glutathione (GSH), a tripeptide that is present in all tissues and that its synthesis and/or regeneration is very important to be able to respond to the increase in oxidizing agents. In this review, we will address the role of glutathione, its synthesis in both the heart and the liver, and its importance in preventing or reducing deleterious ROS effects in cardiovascular diseases.


2012 ◽  
Vol 12 ◽  
pp. 127-132
Author(s):  
Bhanu B Panthi

This research attempts to identify the existing condition of the community managed forest based on the assumption that it will serve as a proxy for the condition of other forests in the mid hills region of Nepal. The research area has an atypical variation in altitude and diverse pattern of vegetation. This study mainly focuses on estimating carbon content in the forest and identifying the species that has more carbon storage capacity. The research signifies the role of forests in mitigation of ‘Global warming’ and ‘Climate change’ by storing carbon in tree biomass. These types of community based forest management programs are significant for their additional carbon sequestration through the avoidance of deforestation and degradation. The carbon sequestration have a significant contribution to environmental benefits, any shrinkage of forests have an enormous impact on CO2 emission with long term consequences. Thus, the development and expansion of community managed forests provide many benefits to the adjacent community and globally at large.DOI: http://dx.doi.org/10.3126/njst.v12i0.6490 Nepal Journal of Science and Technology 12 (2011) 127-32 


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ulla Hakala

Purpose Listening to the customers has long been a key phrase and success element in product branding. This paper aims to highlight the importance of listening to residents during the branding of a place. The study explores ways of listening to residents to ensure they are heard and also discusses the challenges and benefits related to place branding flowing from having residents participate in decision-making processes. Design/methodology/approach Listening to residents and offering opportunities to participate requires place branders to fully attend to, comprehend and respond to residents’ comments, requests, ideas and feedback. This study reports on how two Nordic cities – Turku and Helsinki – listen to their residents. The data used comprise face-to-face interviews, telephone and e-mail conversations and documentary material. Findings Residents should not be considered as one homogeneous target; participation options and channels should be adapted to the demographics and geographic issues of the different regions and resident groups. Research limitations/implications The role of residents and the importance of listening are crucial features in the emerging concept of inclusive place branding (Kavaratzis et al., 2017); its future conceptual development could benefit from the case examples at hand. Practical implications City authorities should listen to residents and provide them with opportunities to actively contribute to decision-making. Other cities could learn from the examples introduced in the paper. Originality/value This paper documents two Nordic examples of cities putting into practice a policy of listening to the residents, a previously neglected research area.


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