Advances in two-dimensional materials for energy-efficient and molecular precise membranes for biohydrogen production

Waste management has become an ever-increasing global issue due to population growth and rapid globalisation. For similar reasons, the greenhouse effect caused by fossil fuel combustion, is leading to chronic climate change issues. A novel approach, the waste-to-hydrogen process, is introduced to address the concern of waste generation and climate change with an additional merit of production of a renewable, higher energy density than fossil fuels and sustainable transportation fuel, hydrogen (H2) gas. In the downstream H2 purifying process, membrane separation is one of the appealing options for the waste-to-hydrogen process given its low energy consumption and low operational cost. However, commercial polymeric membranes have hindered membrane separation process due to their low separation performance. By introducing novel two-dimensional materials as substitutes, the limitation of purifying using conventional membranes can potentially be solved. Herein, this article provides a comprehensive review of two-dimensional materials as alternatives to membrane technology for the gas separation of H2 in waste-to-hydrogen downstream process. Moreover, this review article elaborates and provides some perspectives on the challenges and future potential of the waste-to-hydrogen process and the use of two-dimensional materials in membrane technology.

In Situ Chemical Modification with Zwitterionic Copolymers of Nanofiltration Membranes: Cure for the Trade-Off between Filtration and Antifouling Performance

Breaking the trade-off between filtration performance and antifouling property is critical to enabling a thin-film nanocomposite (TFC) nanofiltration (NF) membrane for a wide range of feed streams. We proposed a novel design route for TFC NF membranes by grafting well-defined zwitterionic copolymers of [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA) and 2-aminoethyl methacrylate hydrochloride (AEMA) on the polyamide surfaces via an in situ surface chemical modification process. The successful grafting of a zwitterionic copolymer imparted the modified NF membranes with better surface hydrophilicity, a larger actual surface area (i.e., nodular structures), and a thinner polyamide layer. As a result, the water permeability of the modified membrane (i.e., TFC-10) was triple that of the pristine TFC membrane while maintaining high Na₂SO₄ rejection. We further demonstrated that the TFC-10 membrane possessed exceptional antifouling properties in both static adsorption tests and three cycles of dynamic protein and humic acid fouling tests. To recap, this work provides valuable insights and strategies for the fabrication of TFC NF membranes with simultaneously enhanced filtration performance and antifouling property.

Checkpoint blockade immunotherapy reshapes the high-dimensional phenotypic heterogeneity of murine intratumoural neoantigen-specific CD8+ T cells

The analysis of neoantigen-specific CD8⁺ T cells in tumour-bearing individuals is challenging due to the small pool of tumour antigen-specific T cells. Here we show that mass cytometry with multiplex combinatorial tetramer staining can identify and characterize neoantigen-specific CD8⁺ T cells in mice bearing T3 methylcholanthrene-induced sarcomas that are susceptible to checkpoint blockade immunotherapy. Among 81 candidate antigens tested, we identify T cells restricted to two known neoantigens simultaneously in tumours, spleens and lymph nodes in tumour-bearing mice. High-dimensional phenotypic profiling reveals that antigen-specific, tumour-infiltrating T cells are highly heterogeneous. We further show that neoantigen-specific T cells display a different phenotypic profile in mice treated with anti-CTLA-4 or anti-PD-1 immunotherapy, whereas their peripheral counterparts are not affected by the treatments. Our results provide insights into the nature of neoantigen-specific T cells and the effects of checkpoint blockade immunotherapy.

Immune checkpoint blockade (ICB) therapies can unleash anti-tumour T-cell responses. Here the authors show, by integrating MHC tetramer multiplexing, mass cytometry and high-dimensional analyses, that neoantigen-specific, tumour-infiltrating T cells are highly heterogeneous and are subjected to ICB modulations.

A clinical survey on compliance in the treatment of rhinitis using nasal steroids

BACKGROUND

In the treatment of persistent rhinitis, the observed efficacy with intranasal steroids in clinical practice often falls short of that reported in clinical trials. We postulate that this could be due to patient non-compliance and thus designed this study to evaluate the impact of patient compliance on the efficacy of treatment in patients with persistent rhinitis.

METHODS

Sixty-three consecutive adult patients with allergic and non-allergic rhinitis, treated with intranasal triamcinolone acetonate, were included in the study. Compliance was determined both by direct questioning and by measuring the weight of medication consumed (WMC) after 30 days of therapy. Nasal symptom scores were used to determine treatment efficacy.

RESULTS

Forty-nine patients (77.8%) reported a forgetfulness of using medication for a few times (1-5 times) during the treatment period. Less than 50% compliance was reported by one patient (1.6%) but detected in seven patients (11%) by WMC. There was a significant (P < 0.001) improvement in mean total symptom score before (7.45 +/- 1.99) and after (3.59 +/- 2.72) treatment in patients with WMC of at least 50%, but not when WMC was <50% (8.43 +/- 1.72 vs 6.29 +/- 2.43; P = 0.114). With >50% WMC, the positive predictive values for relief of each symptom were rhinorrhoea: 78%, nasal itch: 70%, nasal obstruction: 67% and sneezing: 65%.

CONCLUSION

Patients compliance has a significant impact on treatment efficacy with intranasal steroids. There is a discrepancy between reported and actual compliance. It is thus important to establish the actual compliance when evaluating patients who fail to respond to therapy.

Hypertension in young adults--an under-estimated problem

AIM

To study the prevalence of hypertension and "white coat hypertension" in young adult Asian males, and identify the associated risk factors.

METHODS

Population-based descriptive analysis of 3,352 Singapore military conscripts presenting consecutively for medical screening, followed by case-control study of subjects with elevated blood pressure. A standard protocol for assessing elevated blood pressure, 24-hour ambulatory monitoring and detailed interviews were performed. Main study outcomes are prevalence rate of hypertension and "white coat hypertension", mean blood pressure readings, and adjusted odds ratios for associated variables.

RESULTS

Prevalence of hypertension and "white coat hypertension" was 1.6% (95% CI 1.2, 2.0) and 2.0% (95% CI 1.5, 2.5) respectively. Twenty-four-hour ambulatory monitoring was required to differentiate the two conditions, with a fall of 22.5 mmHg (95% CI 19.7, 25.3) observed between first visit and day-time ambulatory mean systolic blood pressures. There was strong association between hypertension and obesity (adjusted odds ratio using Body Mass Index: 1.19, p<0.001). Other important variables included parental history of hypertension, Malay ethnicity and low socio-economic status, although there was no significant correlation in our regression model.

CONCLUSION

This study provides population-based data on hypertension in young Asian adults. While the prevalence of hypertension is low compared to older age groups, it remains important to detect cases early, as appropriate treatment may mitigate long-term cardiovascular risks and reduce target organ damage. There is a clear role for ambulatory blood pressure monitoring for differentiating true hypertension from "white coat hypertension". There may be a role for targeted screening of high-risk groups, particularly the obese.

Effects of vagal perineural capsaicin treatment on vagal efferent and airway neurogenic responses in anesthetized rats

The acute effect of vagal perineural capsaicin treatment (VPCT) on parasympathetic bradycardia and tracheal neurogenic protein extravasation was examined. In nine anesthetized male Wistar rats the effect of VPCT on the bradycardia induced by electrical stimulation of the vagus was examined. In 24 anesthetized male Wistar rats the effect of VPCT on the tracheal protein extravasation induced by the inhalation of capsaicin aerosols was also studied. VPCT did not alter the bradycardia induced by vagal stimulation or the tracheal protein extravasation induced by the inhalation of capsaicin aerosol. The results of these studies further demonstrate the selectivity of perineural capsaicin treatment on vagal sensory nonmyelinated fibers in the rat and indicate that it is a useful tool for examining the role of sensory vagal C-fibers in pulmonary and cardiovascular reflexes and in isolating C-fiber-mediated reflex responses from those mediated by the release of neuropeptides.