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Owing to its high thermal and electrical conductivities, its ductility and its overall non-toxicity.sup.1-3, copper is widely used in daily applications and in industry, particularly in anti-oxidation technologies. However, many widespread anti-oxidation techniques, such as alloying and electroplating.sup.1,2, often degrade some physical properties (for example, thermal and electrical conductivities and colour) and introduce harmful elements such as chromium and nickel. Although efforts have been made to develop surface passivation technologies using organic molecules, inorganic materials or carbon-based materials as oxidation inhibitors.sup.4-12, their large-scale application has had limited success. We have previously reported the solvothermal synthesis of highly air-stable copper nanosheets using formate as a reducing agent.sup.13. Here we report that a solvothermal treatment of copper in the presence of sodium formate leads to crystallographic reconstruction of the copper surface and formation of an ultrathin surface coordination layer. We reveal that the surface modification does not affect the electrical or thermal conductivities of the bulk copper, but introduces high oxidation resistance in air, salt spray and alkaline conditions. We also develop a rapid room-temperature electrochemical synthesis protocol, with the resulting materials demonstrating similarly strong passivation performance. We further improve the oxidation resistance of the copper surfaces by introducing alkanethiol ligands to coordinate with steps or defect sites that are not protected by the passivation layer. We demonstrate that the mild treatment conditions make this technology applicable to the preparation of air-stable copper materials in different forms, including foils, nanowires, nanoparticles and bulk pastes. We expect that the technology developed in this work will help to expand the industrial applications of copper. High oxidation resistance, without degradation of thermal or electrical conductivity, is achieved in copper using surface modification by a solvothermal or electrochemical treatment with sodium formate and formation of a thin surface coordination layer., Author(s): Jian Peng [sup.1] , Bili Chen [sup.1] , Zhichang Wang [sup.1] [sup.2] [sup.3] , Jing Guo [sup.4] , Binghui Wu [sup.1] , Shuqiang Hao [sup.1] , Qinghua Zhang [sup.5] [...]

In August 2020, a 63-year-old homeless man with a history of deep vein thrombosis and chronic venous insufficiency was found in his truck, unconscious and covered in feces and maggots. [...]

Cannabinoid hyperemesis syndrome (CHS) is a paradoxical condition in which a long-term cannabis user suffers an episode of intractable vomiting that may last days separated by longer asymptomatic periods of weeks or months. Cannabinoids are often utilized for their antiemetic properties, so CHS can be a puzzling condition, and the diagnosis of CHS may be disputed by patients. Unlike other cyclic vomiting syndromes, CHS can be relieved by hot showers or topical capsaicin. Abstinence from cannabinoids causes CHS to resolve, sometimes in a matter of days or hours. Marijuana users as well as many clinicians are not aware of CHS, and patients may undergo unnecessary tests, scans, and other procedures to get an accurate diagnosis. Symptoms may be severe enough to require hospitalization. With liberalization of marijuana laws and favorable public opinion about the healing properties of cannabis, CHS may be more frequently observed in clinical practice. Keywords Cannabis * Marijuana * Cannabinoid hyperemesis * Cannabinoid vomiting syndrome * Hyperemesis * Cyclic vomiting, Introduction Cannabinoid hyperemesis syndrome (CHS) involves episodic cyclic vomiting that occurs in some cannabis users. Typical symptoms include intractable nausea and vomiting, refractory to conventional antiemetic therapy, often accompanied by [...]

We report Wohlfahrtiimonas chitiniclastica bacteremia in a 75-year-old man in Japan who had squamous cell carcinoma on his shoulder. In September 2016, an unidentified patient was found unconscious on the [...]

Byline: Tapan Kumar Mohanta Abstract The sound wave perception of the animal is one of the most important mediums of communication. It contributed significantly in shaping the behavior, ecology and [...]

Structures visible within the eukaryotic nucleus have fascinated generations of biologists. Recent data show that these structures form in response to gene expression and are highly dynamic in living cells. RNA processing and assembly require many factors but the nucleus apparently lacks any active transport system to deliver these to the RNAs. Instead, processing factors move by diffusion but are concentrated by transient association with functionally related components. At sites of high activity this gives rise to visible structures, with components in dynamic equilibrium with the surrounding nucleoplasm. Processing factors are recruited from this pool by cooperative binding to RNA substrates., It has long been known that eukaryotic nuclei are not homogeneous but contain a variety of subnuclear structures often referred to as nuclear bodies. Most are involved in the synthesis, [...]