Hydrogen bonds in blends of poly(N-isopropylacrylamide), poly(n-ethylacrylamide) homopolymers, and carboxymethyl cellulose

Recently, it was reported that the physical crosslinking exhibited by some biopolymers could provide multiple benefits to biomedical applications. In particular, grafting thermoresponsive polymers onto biopolymers may enhance the degradability or offer other features, as thermothickening behavior. Thus, different interactions will affect the different hydrogen bonds and interactions from the physical crosslinking of carboxymethyl cellulose, the lower critical solution temperatures (LCSTs), and the presence of the ions. This work focuses on the study of blends composed of poly(N-isopropylacrylamide), poly(N-ethylacrylamide), and carboxymethyl cellulose in water and water/methanol. The molecular features, thermoresponsive behavior, and gelation phenomena are deeply studied. The ratio defined by both homopolymers will alter the final properties and the gelation of the final structures, showing that the presence of the hydrophilic groups modifies the number and contributions of the diverse hydrogen bonds.The authors want to acknowledge the funding obtained from the National Science Foundation of China (21574086), Shenzhen Fundamental Research Funds (No. KC2014ZDZJ0001A), Shenzhen Sci & Tech research grant (ZDSYS201507141105130), and China Postdoctoral Science Foundation Grant (2018M633119)

Electrochemical monitoring of the oxidative coupling of alkynes catalyzed by triphenylphosphine gold complexes

Electrochemical monitoring of the oxidative coupling of alkynes in the homogeneous phase through catalytic cycles involving triphenylphosphine gold complexes and selectfluor as oxidant reveals that at least two gold species in +3 and +1 oxidation states are implicated. Electrochemically driven homocoupling of terminal alkynes using molecular oxygen as the oxidant can be performed using such catalysts.Domenech Carbo, A.; Leyva Perez, A.; Al-Resayes, SI.; Corma Canós, A. (2012). Electrochemical monitoring of the oxidative coupling of alkynes catalyzed by triphenylphosphine gold complexes. Electrochemistry Communications. 19:145-148. doi:10.1016/j.elecom.2012.02.038S1451481

Concentration Effect over Thermoresponse Derived from Organometallic Compounds of Functionalized Poly(N-isopropylacrylamide-co-dopamine Methacrylamide)

The functionalization of smart polymers is opening a new perspective in catalysis, drug carriers and biosensors, due to the fact that they can modulate the response regarding conventional devices. This smart response could be affected by the presence of organometallic complexes in terms of interactions which could affect the physical chemical properties. In this sense, the thermoresponsive behavior of copolymers based on N-isopropylacrylamide (NIPAM) could be affected due to the presence of hydrophobic groups and concentration effect. In this work, the functionalization of a copolymer based on NIPAM and dopamine methacrylamide with different amounts of bis(cyclopentadienyl)titanium (IV) dichloride was carried out. The resulting materials were characterized, showing a clear idea about the mechanism of functionalization through FTIR spectroscopy. The thermoresponsive behavior was also studied for various polymeric solutions in water by UV–vis spectroscopy and calorimetry. The hydrophobic interactions promoted by the organometallic complex could affect the transition associated with the lower critical solution temperature (LCST), specifically, the segments composed by pure NIPAM. That fact would explain the reduction of the width of the LCST-transition, contrary to what could be expected. In addition, the hydrophobicity was tested by the contact angle and also DNA interactions.The authors want to thank the funding obtained from Ministerio de Ciencia, Innovación y Universidades (MCIU), Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, UE) through the project: PGC2018-095364-B-I00

Functional genomics analysis of Leptin-Melanocortin system genes reveals candidate genes associated rapid growth and high carcass yield in sheep

The Leptin-Melanocortin System (LMS) is an important regulatory system involved in appetite and energy balance in many organisms, including sheep. Functional genomics analysis of LMS genes can provide insights into the genetic factors that influence rapid growth and high carcass yield in sheep. However, the genetic potential of sheep growth and reproduction has not been fully exploited. Therefore, identifying genes that regulate growth and reproduction would offer strategies for improving the yield and quality of sheep meat. In this study, to explore the possible molecular mechanisms underlying rapid growth and muscular high-yield carcass in sheep, we screened 14 genes, which were previously claimed to be associated with such traits in humans and rodents. The FST outlier approach implemented in LOSITAN detected the loci under selection. These candidate genes were connected to complicated biological processes, including the regulation of eating behavior, energy balance, and the positive regulation of the cAMP biosynthetic process, according to the gene ontology (GO) study. In addition, the 14 genes' re-sequence data revealed 7,226 SNPs. The MC4R, STAT3, BDNF, and TUB genes were discovered to be an outlier and significantly under positive selection using the fixation index (FST) based technique with the tentative combined allocation of mean heterozygosity and FST. Differentially expressed genes were found, and their functions were assigned using a functional genomics approach. Results showed that these genes are crucial in determining sheep features including size and meat quality. Insights are gained into the molecular mechanisms behind these phenotypic variations, and possible genes for future sheep breeding initiatives are provided. This research proves the value of functional genomics analysis in identifying the heritable components of valuable sheep agriculture traits.The authors extend their appreciation to the Researchers Supporting Project number (RSP2023R27) King Saud University, Riyadh, Saudi Arabia.Peer reviewe

Development of a quality indicator set to measure and improve quality of ICU care in low- and middle-income countries

PURPOSE: To develop a set of actionable quality indicators for critical care suitable for use in low- or middle-income countries (LMICs). METHODS: A list of 84 candidate indicators compiled from a previous literature review and stakeholder recommendations were categorised into three domains (foundation, process, and quality impact). An expert panel (EP) representing stakeholders from critical care and allied specialties in multiple low-, middle-, and high-income countries was convened. In rounds one and two of the Delphi exercise, the EP appraised (Likert scale 1–5) each indicator for validity, feasibility; in round three sensitivity to change, and reliability were additionally appraised. Potential barriers and facilitators to implementation of the quality indicators were also reported in this round. Median score and interquartile range (IQR) were used to determine consensus; indicators with consensus disagreement (median < 4, IQR ≤ 1) were removed, and indicators with consensus agreement (median ≥ 4, IQR ≤ 1) or no consensus were retained. In round four, indicators were prioritised based on their ability to impact cost of care to the provider and recipient, staff well-being, patient safety, and patient-centred outcomes. RESULTS: Seventy-one experts from 30 countries (n = 45, 63%, representing critical care) selected 57 indicators to assess quality of care in intensive care unit (ICU) in LMICs: 16 foundation, 27 process, and 14 quality impact indicators after round three. Round 4 resulted in 14 prioritised indicators. Fifty-seven respondents reported barriers and facilitators, of which electronic registry-embedded data collection was the biggest perceived facilitator to implementation (n = 54/57, 95%) Concerns over burden of data collection (n = 53/57, 93%) and variations in definition (n = 45/57, 79%) were perceived as the greatest barrier to implementation. CONCLUSION: This consensus exercise provides a common set of indicators to support benchmarking and quality improvement programs for critical care populations in LMICs

Influence of Ag nanoparticles on state of the art MnO2 nanorods performance as an electrocatalyst for lithium air batteries

Abstract The need for an alternative and efficient electrocatalyst to replace Pt-based noble materials is a goal of prime importance in Li– air battery technology. In this work, novel silver nanoparticles-incorporated MnO2 nanorods as an air electrode bifunctional catalyst have been synthesized by a simple polyol method. The physical characteristics of the thus prepared materials are analyzed by X-ray diffraction (XRD), SEM, and Brunauer–Emmett–Teller (BET) techniques. These analyses confirmed the successful synthesis of 20 to 25 nm-sized different weight % Ag nanoparticles incorporated on α-MnO2 nanorods. Linear sweeping voltammetric results of AgMnO2 showed improved ORR performance as compared to α- MnO2 nanorods in terms of the onset potential, half wave potential and limiting current. The addition of catalysts has significantly increased the discharge capacity and overall performance of the cells. The first discharge curve of 5 wt% Ag MnO2 sample reached a maximum capacity of 3500 mAhg-1 at 2.0 V with a current density of 0.1 mA cm−2 with a plateau between 2.7 and 2.6 V. Long term stability of increasing weight percentage of Ag nanoparticles on MnO2 samples is increased

Synthesis and Characterization of Reduced Graphene Oxide from Indigenous Coal: A Non-Burning Solution

Abstract: A great deal of research has been made into producing graphene or graphene oxide by utilizing graphite as a starting material. An alternate method of producing graphene is using low-grade coal as a starting material. Due to the abundance of coal in Pakistan and increased environmental concern from Government bodies and environmental agencies alike, increased awareness is being made to move over to non-burning solutions to fossil fuels. Experiments were performed on two ranks of coal in parallel; lignite and sub-bituminous. Coal was pretreated first to remove the undesired impurities, which could hinder the graphene synthesis later on. Acid washing with multiple waters was done, followed by carbonization in the furnace. After the pretreatment, the Hummers method was chosen as a chemical process for synthesizing graphene. It is a less complex method, can be easily performed with available resources, and is comparatively cheaper and environmentally friendly. The resulting sample was tested with SEM and EDS, and graphene oxide was confirmed. It was followed by a water-based reduction method to produce reduced graphene oxide from graphene oxide. This modified hydrothermal method was chosen for its eco-friendliness. The final sample was dried and tested with XRD, SEM, FTIR, and RAMAN to authenticate the type of graphene produced. Graphene has remarkable properties, including very high tensile modulus, extremely high thermal conductivity, and charge carrier mobility exceeding 200,000 cm2V-1s-1. Such properties are reason enough to explore low cost, environment friendly, and scalable means of graphene production. Potential graphene applications in various medical, chemical and industrial processes are enhanced or enabled by using new graphene materials. Keywords: Coal, Graphene graphite, Hummers method, Hydrothermal method, Water-based reduction method