Water vapour permeability of poly(lactic acid) nanocomposites

A series of poly(lactic acid) (PLA) nanocomposites containing from 1 up to 6 wt% of montmorillonite layered silicate were prepared by melt compounding followed by compression moulding. The morphology of the nanocomposites was investigated using transmission electron microscopy (TEM) and wide-angle X-ray diffraction (WAXD) and it was confirmed that the nanocomposite structures were intercalated. The average aspect ratio of the compounded nanoclay was found to be 50. Water vapour transmission rates (WVTR) through the films were measured at 38 °C and at a relative humidity of 90%. It was found that the measured values of WVTR decreased with increasing nanoclay content up to a value of 5 wt% and the results gave good agreement with predictions from the Nielsen ‘tortuous path’ model

Application of microbial organic fertilizers promotes the utilization of nutrients and restoration of microbial community structure and function in rhizosphere soils after dazomet fumigation

IntroductionSoil fumigant dazomet is a broad-spectrum nematicide and fungicide that can kill non-target microbes. Fungicides or organic fertilizers are often added after fumigation to improve the recovery of soil microbes. However, the effect of adding microbial organic fertilizers (MOF) after fumigation on the structure and function of rhizosphere soil microbial communities of crops is unclear.MethodsTherefore, we investigated the effects of adding Junweinong and Junlisu MOFs after dazomet fumigation on the structure and function of rhizosphere microbial communities and its relationship with soil properties and enzyme activities.Results and discussionThe results showed that the addition of these two MOFs after dazomet fumigation significantly reduced the rhizosphere soil available phosphorus, available potassium, organic matter content, and urease, alkaline phosphatase, and catalase activities, but increased the soil pH compared with the fumigation treatment. The application of MOFs after fumigation resulted in significant enrichment of bacteria such as Gaiella, norank_f_Vicinamibacteraceae, and Flavisolibacter and fungi such as Peroneutypa, Olpidium, and Microascus in the rhizosphere soil of the crop and increased the relative abundance of functional genes of 13 kinds of amino acids metabolism, pyruvate metabolism, TCA cycle, and pentose phosphate pathway as well as endophytic and epiphytic functional groups in the rhizosphere soil. In particular, NH4+-N, pH, and AK had the greatest effect on rhizosphere microorganisms. Overall, the addition of MOFs after fumigation promoted crop root nutrient uptake, enhanced rhizosphere soil microbial metabolism, allowed more beneficial communities to colonize the roots, and promoted soil microbiological health

ZnS/CuS nanoparticles encapsulated in multichannel carbon fibers as high-performance anode materials for flexible Li-ion capacitors

Transition metal sulfides (TMSs) are widely recognized for their potential as anode materials in the development of flexible lithium-ion capacitors (FLICs) owing to their high theoretical capacity. However, their practical application has been significantly limited by rapid capacity decay and sluggish kinetics associated with TMS volume variation. In response to these challenges, we have prepared ZnS/CuS nanoparticles embedded in continuous and multichannel carbon fibers (CFs). This was achieved through a process involving blow-spinning and subsequent sulfidation. Notably, the electrochemical performance of these materials was largely improved, owing to the synergistic effect of bimetallic sulfides. The ZnS/CuS-CF anode material demonstrated a high specific capacity of over 900 mAh g−1 at a current density of 0.2 A g−1. Furthermore, it exhibited superior rate capacity (300 mAh g−1 at 20 A g−1) and excellent cyclic stability, maintaining its performance over 1000 cycles at 10 A g−1. We also prepared lithium-ion capacitors (LICs) using the same method. These LICs exhibited a maximum energy density of 136 Wh kg−1, a high power density of 43.5 kW kg−1, and an impressive cyclic stability over 4000 cycles. In addition, the FLICs, when configured in the form of a pouch cell, demonstrated significant potential for the development of smart, flexible electronic devices

Prediction of upcoming urinary tract infection after intracerebral hemorrhage: a machine learning approach based on statistics collected at multiple time points

PurposeAccurate prediction of urinary tract infection (UTI) following intracerebral hemorrhage (ICH) can significantly facilitate both timely medical interventions and therapeutic decisions in neurocritical care. Our study aimed to propose a machine learning method to predict an upcoming UTI by using multi-time-point statistics.MethodsA total of 110 patients were identified from a neuro-intensive care unit in this research. Laboratory test results at two time points were chosen: Lab 1 collected at the time of admission and Lab 2 collected at the time of 48 h after admission. Univariate analysis was performed to investigate if there were statistical differences between the UTI group and the non-UTI group. Machine learning models were built with various combinations of selected features and evaluated with accuracy (ACC), sensitivity, specificity, and area under the curve (AUC) values.ResultsCorticosteroid usage (p < 0.001) and daily urinary volume (p < 0.001) were statistically significant risk factors for UTI. Moreover, there were statistical differences in laboratory test results between the UTI group and the non-UTI group at the two time points, as suggested by the univariate analysis. Among the machine learning models, the one incorporating clinical information and the rate of change in laboratory parameters outperformed the others. This model achieved ACC = 0.773, sensitivity = 0.785, specificity = 0.762, and AUC = 0.868 during training and 0.682, 0.685, 0.673, and 0.751 in the model test, respectively.ConclusionThe combination of clinical information and multi-time-point laboratory data can effectively predict upcoming UTIs after ICH in neurocritical care

DEVELOPMENT OF RHENIUM, PLATINUM, AND RUTHENIUM METALLODRUG CANDIDATES

243 pagesThe clinical success of cisplatin and other platinum-based chemotherapeutics has inspired extensive research efforts to develop alternative metallodrugs with improved pharmacological properties. The first section of this dissertation focuses on design of novel metallodrugs for cytotoxic anticancer applications. Recently, rhenium(I) tricarbonyl complexes have attracted significant attention as novel anticancer agents, because their mechanisms of action are distinct from the DNA-binding pathways that are operative for platinum(II) complexes. Chapter 1 is a comprehensive review of the recent developments of multimetallic rhenium(I) tricarbonyl complexes for therapeutic and diagnostic applications. Chapter 2 describes the development of the first Pt(IV)Re(I) molecular conjugates as photoactivated anticancer agents. The second section of this dissertation explores the use of metal complexes as cytoprotective agents targeting the mitochondrial calcium uniporter (MCU), a transmembrane protein that is responsible for shuttling cytosolic Ca2+ into mitochondria. Dysregulation of the MCU can trigger an overload of mitochondrial Ca2+, which is implicated in the progression of cardiovascular and neurodegenerative diseases. As such, the chemical inhibition of MCU represents a promising therapeutic strategy. Chapter 3 summarizes recent advances in metal-based MCU inhibitors and highlights a diruthenium coordination complex, Ru265, as the state-of-the-art MCU inhibitor due to its excellent potency, selectivity, and cellular permeability. Chapter 3 also outlines the structure-activity relationship of Ru265-based MCU inhibitors. Chapter 4 describes a ferrocene-functionalized analogue of Ru265 and demonstrates that the cellular permeability of this class of MCU inhibitors can be rationally improved through ligand functionalization. Finally, Chapter 5 details the development of the first fluorogenic MCU inhibitor, a coumarin-functionalized analogue of Ru265. Collectively, these results demonstrate the potential of metal complexes for cytotoxic and cytoprotective applications and provide strategies for the rational design of metallodrug candidates

Kinetics and thermodynamics study on removal of cr(VI) from aqueous solutions using acid-modified banana peel (ABP) adsorbents

Banana peel waste is abundant and can be utilized as a low-cost adsorbent for removing toxic Cr (VI) from wastewater. The acid modification of banana peels significantly enhances their adsorption capacity for Cr (VI). An adsorbent was prepared by treating banana peel powder with 50% H2SO4 at 50 °C for 24 h. The acid treatment increased the surface area of the adsorbent from 0.0363 to 0.0507 m2/g. The optimum adsorbent dose was found to be 1 g/L for the complete removal of Cr (VI) from 100 ppm solutions. The adsorption capacity was 161 mg/g based on the Langmuir isotherm model. The adsorption kinetics followed a pseudo-second order model. Increasing the temperature from 20 to 50 °C increased the initial adsorption rate but had a minor effect on the equilibrium adsorption capacity. Thermodynamics studies showed that the process was spontaneous and endothermic. The activation energy was estimated as 24.5 kJ/mol, indicating physisorption. FTIR analyses before and after adsorption showed the involvement of hydroxyl, carbonyl and carboxyl groups in binding the Cr (VI). The Cr (VI) was reduced to Cr (III), which then bound to functional groups on the adsorbent. Desorption under acidic conditions could recover 36% of the adsorbed Cr as Cr (III). No desorption occurred at a neutral pH, indicating irreversible adsorption. Overall, acid-modified banana peel is an efficient, low-cost and eco-friendly adsorbent for removing toxic Cr (VI) from wastewater

A Fluorogenic Inhibitor of the Mitochondrial Calcium Uniporter.

Inhibitors of the mitochondrial calcium uniporter (MCU) are valuable tools for studying the role of mitochondrial Ca2+ in various pathophysiological conditions. In this study, a new fluorogenic MCU inhibitor, RuOCou, is presented. This compound is an analogue of the known MCU inhibitor Ru265 that contains fluorescent axial coumarin carboxylate ligands. Upon aquation of RuOCou and release of the axial coumarin ligands, a simultaneous increase in its MCU-inhibitory activity and fluorescence intensity is observed. The fluorescence response of this compound enabled its aquation to be monitored in both HeLa cell lysates and live HeLa cells. This fluorogenic prodrug represents a potential theranostic MCU inhibitor that can be leveraged for the treatment of human diseases related to MCU activity

Kinetics and Thermodynamics Study on Removal of Cr(VI) from Aqueous Solutions Using Acid-Modified Banana Peel (ABP) Adsorbents

Banana peel waste is abundant and can be utilized as a low-cost adsorbent for removing toxic Cr (VI) from wastewater. The acid modification of banana peels significantly enhances their adsorption capacity for Cr (VI). An adsorbent was prepared by treating banana peel powder with 50% H2SO4 at 50 °C for 24 h. The acid treatment increased the surface area of the adsorbent from 0.0363 to 0.0507 m2/g. The optimum adsorbent dose was found to be 1 g/L for the complete removal of Cr (VI) from 100 ppm solutions. The adsorption capacity was 161 mg/g based on the Langmuir isotherm model. The adsorption kinetics followed a pseudo-second order model. Increasing the temperature from 20 to 50 °C increased the initial adsorption rate but had a minor effect on the equilibrium adsorption capacity. Thermodynamics studies showed that the process was spontaneous and endothermic. The activation energy was estimated as 24.5 kJ/mol, indicating physisorption. FTIR analyses before and after adsorption showed the involvement of hydroxyl, carbonyl and carboxyl groups in binding the Cr (VI). The Cr (VI) was reduced to Cr (III), which then bound to functional groups on the adsorbent. Desorption under acidic conditions could recover 36% of the adsorbed Cr as Cr (III). No desorption occurred at a neutral pH, indicating irreversible adsorption. Overall, acid-modified banana peel is an efficient, low-cost and eco-friendly adsorbent for removing toxic Cr (VI) from wastewater