Enhanced Thermoelectric Properties of a Semiconducting Two-Dimensional Metal–Organic Framework via Iodine Loading

We report the first result of a study in which molecular iodine has been incorporated via incipient wetness impregnation into the two-dimensional semiconducting metal–organic framework (MOF) Cu3(2,3,6,7,10,11-hexahydroxytriphenylene)2 Cu3(HHTP)2 to enhance its thermoelectric properties. A power factor of 0.757 μW m–1 K–2 for this MOF was obtained which demonstrates that this provides an effective route for the preparation of moderate-performance thermoelectric MOFs

Fabrication of devices featuring covalently linked MoS2–graphene heterostructures

The most widespread method for the synthesis of 2D–2D heterostructures is the direct growth of one material on top of the other. Alternatively, flakes of different materials can be manually stacked on top of each other. Both methods typically involve stacking 2D layers through van der Waals forces—such that these materials are often referred to as van der Waals heterostructures—and are stacked one crystal or one device at a time. Here we describe the covalent grafting of 2H-MoS2 flakes onto graphene monolayers embedded in field-effect transistors. A bifunctional molecule featuring a maleimide and a diazonium functional group was used, known to connect to sulfide- and carbon-based materials, respectively. MoS2 flakes were exfoliated, functionalized by reaction with the maleimide moieties and then anchored to graphene by the diazonium groups. This approach enabled the simultaneous functionalization of several devices. The electronic properties of the resulting heterostructure are shown to be dominated by the MoS2–graphene interface.The authors acknowledge European Research Council (ERC-PoC- 842606 (E.M.P.); ERC-AdG-742684 (J. S.) and the MSCA program MSCA-IF-2019-892667 (N.M.S.), MINECO (CTQ2017-86060-P (E.M.P.) and CTQ2016-79419-R), Ministerio de Ciencia e Innovación (RTI2018-096075-A-C22 (E.B.), RYC2019-028429-I (E.B.)) the Comunidad de Madrid (MAD2D-CM S2013/ MIT-3007 (E.M.P.), Y2018/NMT-4783 (A.D.)) and the Programa de Atracción del Talento Investigador 2017-T1/IND-5562 (E.B.)). CzechNanoLab Research Infrastructure supported by MEYS CR (LM2018110) are gratefully acknowledged. IMDEA Nanociencia acknowledges support from the Severo Ochoa Programme for Centres of Excellence in R&D (MINECO, grant no. SEV-2016-0686).Peer reviewe

Thermoelectric properties of semiconducting metal-organic framework thin films and composites

In order to study the potential application and efficiency of semiconducting metal organic frameworks (MOFs) as materials for thermoelectric generators (TEG), 2- dimensional and 3- dimensional frameworks have been selected as initial targets. The 2-D framework employed in this investigation possess a honeycomb-like structure, containing Cu ions as nodes and coordinated to hexahydroxytriphenylene (HHTP) organic ligands. In addition, principle experimental studies on the incorporation of molecular iodine on thin films of this framework, Cu3(HHTP)2, via incipient wetness impregnation is demonstrated as an effective route to enhance its thermoelectric performance. Furthermore, the solvothermal synthesis and thermoelectric characterisation of a semiconducting 3-D MOF comprised of divalent FeII/III ions coordinated to tetrahydroxybenzoquinone (THBQ) organic moieties and core-shell like structures constituting Fe-THBQ coated Bi2Te3 nanowires are reported for the first time, expanding the scope of MOF heterostructures in energy conversion technologies. Thermoelectric measurements were performed on MOF pellets and thin films. The incorporation of MOFs as thin films provides a route for the design of new devices, although this is still an issue that is derived from the micro-sized crystals and their poor solubility in any solvent. Especially for those MOFs that exhibit electrical conductivity, the deposition of MOFs onto a given substrate is becoming important in order to assess them in practical applications such as chemical sensors, catalytic coatings and other electronic nanodevices. The fabrication of MOF thin films was conducted via electrochemical and dip coating techniques. The study of different structures of MOFs and their performance as TEGs is expected to expand and offer alternatives to non-toxic, scalable and high-efficiency novel TE material

Electrochemical Deposition and Thermoelectric Characterisation of a Semiconducting 2-D Metal-Organic Framework Thin Film

The electrical conductivity and porosity of the 2-dimensional metal-organic framework Cu3(2,3,6,7,10,11-hexahydroxytriphenylene)2 [Cu3(HHTP)2] make it a promising candidate for thermoelectric applications. In this work, we report the electrochemical synthesis of Cu3(HHTP)2 films by an anodization approach and an evaluation of its thermoelectric properties. The electrochemically synthesised Cu3(HHTP)2 thin films were transferred using a wet chemical method in order to perform electrical measurements. We are reporting the first thermoelectric measurements of this framework both in bulk and thin film form which resulted in Seebeck coefficients of -7.24 µV/K and -121.4 µV/K with a power factor of 3.15x10-3 µW m-1 for the film respectively. The negative Seebeck coefficients suggest that Cu3(HHTP)2 behaves as an n-type semiconductor

Electrochemical deposition and thermoelectric characterisation of a semiconducting 2-D metal-organic framework thin film.

The electrical conductivity and porosity of the 2-dimensional metal–organic framework Cu3(2,3,6,7,10,11-hexahydroxytriphenylene)2 [Cu3(HHTP)2] make it a promising candidate for thermoelectric applications. In this work, we report the electrochemical synthesis of Cu3(HHTP)2 films by an anodization approach and an evaluation of its thermoelectric properties. The electrochemically synthesised Cu3(HHTP)2 thin films were transferred using a wet chemical method in order to perform electrical measurements. We are reporting the first thermoelectric measurements of this framework both in bulk and thin film form which resulted in Seebeck coefficients of −7.24 μV K−1 and −121.4 μV K−1 with a power factor of 3.15 × 10−3 μW m−1 for the film respectively. The negative Seebeck coefficients suggest that Cu3(HHTP)2 behaves as an n-type semiconductor. Since the introduction of conductive MOFs in electronic devices is at an early stage of development, we believe this work validates the use of electrochemical synthetic routes of conducting MOFs to further investigate and expand their applications in thin film technologies

Usefulness of Early Treatment With Melatonin to Reduce Infarct Size in Patients With ST-Segment Elevation Myocardial Infarction Receiving Percutaneous Coronary Intervention (From the Melatonin Adjunct in the Acute Myocardial Infarction Treated With Angioplasty Trial)

Melatonin, an endogenously produced hormone, might potentially limit the ischemia reperfusion injury and improve the efficacy of mechanical reperfusion with primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction (STEMI). This study was aimed to evaluate whether the treatment effect of melatonin therapy in patients with STEMI is influenced by the time to administration. We performed a post hoc analysis of the Melatonin Adjunct in the Acute Myocardial Infarction Treated With Angioplasty trial (NCT00640094), which randomized STEMI patients to melatonin (intravenous and intracoronary bolus) or placebo during pPCI. Randomized patients were divided into tertiles according to symptoms onset to balloon time: first tertile (136 ± 23 minutes), second tertile (196 ± 19 minutes), and third tertile (249 ± 41 minutes). Magnetic resonance imaging was performed within 1 week after pPCI. A total of 146 patients presenting with STEMI within 360 minutes of chest pain onset were randomly allocated to intravenous and intracoronary melatonin or placebo during pPCI. In the first tertile, the infarct size was significantly smaller in the melatonin-treated subjects compared with placebo (14.6 ± 14.2 vs 24.9 ± 9.0%; p = 0.003). Contrariwise, treatment with melatonin was associated with a larger infarct size in the group of patients included in the third tertile (20.5 ± 8.7% vs 11.2 ± 5.2%; p = 0.001), resulting in a significant interaction (p = 0.001). In conclusion, the administration of melatonin in patients with STEMI who presented early after symptom onset was associated with a significant reduction in the infarct size after pPCI

International Nosocomial Infection Control Consortiu (INICC) report, data summary of 43 countries for 2007-2012. Device-associated module

We report the results of an International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2007-December 2012 in 503 intensive care units (ICUs) in Latin America, Asia, Africa, and Europe. During the 6-year study using the Centers for Disease Control and Prevention's (CDC) U.S. National Healthcare Safety Network (NHSN) definitions for device-associated health care–associated infection (DA-HAI), we collected prospective data from 605,310 patients hospitalized in the INICC's ICUs for an aggregate of 3,338,396 days. Although device utilization in the INICC's ICUs was similar to that reported from ICUs in the U.S. in the CDC's NHSN, rates of device-associated nosocomial infection were higher in the ICUs of the INICC hospitals: the pooled rate of central line–associated bloodstream infection in the INICC's ICUs, 4.9 per 1,000 central line days, is nearly 5-fold higher than the 0.9 per 1,000 central line days reported from comparable U.S. ICUs. The overall rate of ventilator-associated pneumonia was also higher (16.8 vs 1.1 per 1,000 ventilator days) as was the rate of catheter-associated urinary tract infection (5.5 vs 1.3 per 1,000 catheter days). Frequencies of resistance of Pseudomonas isolates to amikacin (42.8% vs 10%) and imipenem (42.4% vs 26.1%) and Klebsiella pneumoniae isolates to ceftazidime (71.2% vs 28.8%) and imipenem (19.6% vs 12.8%) were also higher in the INICC's ICUs compared with the ICUs of the CDC's NHSN

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field