Interfacial alloying between lead halide perovskite crystals and hybrid glasses.

The stellar optoelectronic properties of metal halide perovskites provide enormous promise for next-generation optical devices with excellent conversion efficiencies and lower manufacturing costs. However, there is a long-standing ambiguity as to whether the perovskite surface/interface (e.g. structure, charge transfer or source of off-target recombination) or bulk properties are the more determining factor in device performance. Here we fabricate an array of CsPbI3 crystal and hybrid glass composites by sintering and globally visualise the property-performance landscape. Our findings reveal that the interface is the primary determinant of the crystal phases, optoelectronic quality, and stability of CsPbI3. In particular, the presence of a diffusion "alloying" layer is discovered to be critical for passivating surface traps, and beneficially altering the energy landscape of crystal phases. However, high-temperature sintering results in the promotion of a non-stoichiometric perovskite and excess traps at the interface, despite the short-range structure of halide is retained within the alloying layer. By shedding light on functional hetero-interfaces, our research offers the key factors for engineering high-performance perovskite devices.

Recent advances in enzymatic biofuel cells enabled by innovative materials and techniques.

The past few decades have seen increasingly rapid advances in the field of sustainable energy technologies. As a new bio- and eco-friendly energy source, enzymatic biofuel cells (EBFCs) have garnered significant research interest due to their capacity to power implantable bioelectronics, portable devices, and biosensors by utilizing biomass as fuel under mild circumstances. Nonetheless, numerous obstacles impeded the commercialization of EBFCs, including their relatively modest power output and poor long-term stability of enzymes. To depict the current progress of EBFC and address the challenges it faces, this review traces back the evolution of EBFC and focuses on contemporary advances such as newly emerged multi or single enzyme systems, various porous framework-enzyme composites techniques, and innovative applications. Besides emphasizing current achievements in this field, from our perspective part we also introduced novel electrode and cell design for highly effective EBFC fabrication. We believe this review will assist readers in comprehending the basic research and applications of EBFCs as well as potentially spark interdisciplinary collaboration for addressing the pressing issues in this field.

Folate and Choline: Does It Take Two to Tango in Early Programming of Disease?

BACKGROUND: The early life period marks a critical time during which the health trajectory of offspring can be shaped by external influences including maternal nutrition. Folate and choline are water-soluble micronutrients important for fetal development and involved in one-carbon metabolism. Intakes above and below the recommendations commonly occur for both of these nutrients including over-consumption of synthetic folic acid due to widespread vitamin supplement uses and discretionary fortification practices, whereas choline is under-consumed by a majority of the populations including pregnant women. Despite these intake patterns, their long-term impact on offspring health is largely unknown. Moreover, limited attention has been on the combined effects of folate and choline despite being metabolically interrelated as methyl nutrients. This review summarizes evidence from animal models and human studies investigating the role of inadequate or supplemental maternal intakes of folic acid, choline and combined effects of folic acid, and choline as modulators of health and disease in offspring. With the recent rise in the prevalence of obesity and metabolic diseases, our primary measures of interest were metabolic outcomes. SUMMARY: Studies examining the role of maternal intakes of folic acid and/or choline in metabolic phenotypes of offspring have mostly been conducted in animal models with a limited number of reports that consider folate and choline together. An interdependent relationship has been demonstrated between folate and choline in studies where a deficiency in one leads to metabolic aberrations in another. Both deficient and excess maternal intakes of folic acid (in varying doses) have been shown to increase risk of obesity and characteristics of the metabolic syndrome in offspring but these findings were restricted to animal studies. Potential metabolic benefits of choline have been suggested in the presence of obesogenic environment but human data were sparse. An imbalanced intake of high folic acid and inadequate choline in the gestational diet created adverse consequences consistent with the obesogenic phenotypes whereas narrowing this imbalance with high choline blocked these effects. Mechanisms by which maternal folate and/or choline influence offspring outcomes may involve epigenetic modification of gene expression with DNA methylation that can be altered globally and gene-specifically. However, the effects of epigenetic programming were inconsistent as compensatory changes in metabolic products may occur and other contributors including the gut microbiota may provide additional insights into the mechanisms. KEY MESSAGES: Maternal intakes of folic acid and/or choline can impact offspring's long-term health, with metabolic consequences that may arise from imbalances between folate and choline. However, there is a paucity of mechanistic understanding as various contributors influence programming effects including those beyond epigenetics. As folate and choline are metabolically interrelated, future studies need to consider both nutrients to better elucidate metabolic programming of health and disease.

Metal-organic framework glass composites.

The melting phenomenon in metal-organic frameworks (MOFs) has been recognised as one of the fourth generation MOF paradigm behaviours. Molten MOFs have high processibility for producing mechanically robust glassy MOF macrostructures, and they also offer highly tunable interfacial characteristics when combined with other types of functional materials, such as crystalline MOFs, inorganic glass and metal halide perovskites. As a result, MOF glass composites have emerged as a family of functional materials with dynamic properties and hierarchical structural control. These nanocomposites allow for sophisticated materials science studies as well as the fabrication of next-generation separation, catalysis, optical, and biomedical devices. Here, we review the approaches for designing, fabricating, and characterising MOF glass composites. We determine the key application opportunities enabled by these composites and explore the remaining hurdles, such as improving thermal and chemical compatibility, regulating interfacial properties, and scalability.

Modification of the serotonergic systems and phenotypes by gestational micronutrients.

Micronutrients consumed in excess or imbalanced amounts during pregnancy may increase the risk of metabolic diseases in offspring, but the mechanisms underlying these effects are unknown. Serotonin (5-hydroxytryptamine, 5-HT), a multifunctional indoleamine in the brain and the gut, may have key roles in regulating metabolism. We investigated the effects of gestational micronutrient intakes on the central and peripheral serotonergic systems as modulators of the offspring's metabolic phenotypes. Pregnant Wistar rats were fed an AIN-93G diet with 1-fold recommended vitamins (RV), high 10-fold multivitamins (HV), high 10-fold folic acid with recommended choline (HFolRC), or high 10-fold folic acid with no choline (HFolNC). Male and female offspring were weaned to a high-fat RV diet for 12 weeks. We assessed the central function using the 5-HT2C receptor agonist, 1-(3-chlorophenyl)piperazine (mCPP), and found that male offspring from the HV- or HFolRC-fed dams were less responsive (P < 0.05) whereas female HFolRC offspring were more responsive to mCPP (P < 0.01) at 6 weeks post-weaning. Male and female offspring from the HV and HFolNC groups, and male HFolRC offspring had greater food intake (males P < 0.001; females P < 0.001) and weight gain (males P < 0.0001; females P < 0.0001), elevated colon 5-HT (males P < 0.01; females P < 0.001) and fasting glucose concentrations (males P < 0.01; females P < 0.01), as well as body composition toward obesity (males P < 0.01; females P < 0.01) at 12 weeks post-weaning. Colon 5-HT was correlated with fasting glucose concentrations (males R2=0.78, P < 0.0001; females R2=0.71, P < 0.0001). Overall, the serotonergic systems are sensitive to the composition of gestational micronutrients, with alterations consistent with metabolic disturbances in offspring.

Validation and Repeatability of the Epidermolysis Bullosa Eye Disease Index in Dystrophic Epidermolysis Bullosa.

PURPOSE: Dystrophic epidermolysis bullosa (DEB) is a devastating condition that causes painful corneal abrasions and vision loss. Epidermolysis Bullosa Eye Disease Index (EB-EDI) for the first time captures and quantifies EB-specific assessment of ocular symptoms and activities of daily living scales. This survey will become critical in developing new interventions on patients' quality of life. METHODS: Three-part set of the EB-EDI baseline, EB-EDI interval, and Ocular Surface Disease Index (OSDI) survey was distributed to 92 patients with DEB who previously reported eye symptoms on previous surveys. It was then posted online through several EB patient organizations. We compared the EB-EDI with the gold standard OSDI and examined the repeatability of the EB-EDI over a 7- to 15-day interval. RESULTS: Of the 45 individuals who initially responded, 30 of 45 (67%) completed the surveys sent 7 to 15 days later. The age of participants ranged from 6 to 51 years (mean 21 ± 15 years), and 60% (18 of 30) of participants were younger than 18 years. The overall Cronbach alpha values for the subscales of EB-EDI baseline and interval tools presented a good internal consistency (≥0.7). From 2 visits, the domain scores of EB-EDI baseline (0.94) and interval tools (0.83) were shown to have excellent test-retest reliability (intraclass correlation coefficient >0.8). By comparison, OSDI had the intraclass correlation coefficient score of 0.72 ± 0.11. The convergent validation analysis showed that correlations between the domain scores of EB-EDI baseline and interval tools and the subscales of the OSDI reached the hypothesized strength. CONCLUSIONS: Based on a 30-person repeated-measures study, we found that the EB-EDI has excellent reliability and validity specifically in patients with DEB.

Phase control of ZIF-7 nanoparticles via mechanochemical synthesis.

Mechanochemical synthesis is a greener synthesis route to form functional metal organic frameworks (MOFs) compared to the typical solvothermal method. Here we demonstrate the crystal phase control of a widely functional zeolitic imidazolate framework, ZIF-7, and its variations via the mechanochemical synthesis route.

Propulsion, deformation, and confinement response of hollow nanocellulose millimotors.

HYPOTHESIS: Micromotor and nanomotor particles are typically made using dense solid particles that can sediment or be trapped in confined flow environments. Creation of much larger motors should be possible if a very low-density system is used with sufficient strength to carry liquid and still experience propulsive motion. Light, dense millimotors should also be able to deform more than dense solid ones in constrictions. EXPERIMENTS: Millimotors are created from permeable capsules of bacterial cellulose that are coated with catalse-containing metal-organic frameworks, enabling reactive propulsion in aqueous hydrogen peroxide. The motion of the motors is quantified using particle tracking and the deformation is measured using microcapillary compression and flow through confined channels. FINDINGS: Two different propulsion mechanisms are dominant depending on the motor surface chemistry: oxygen bubbles are expelled from hydrophilic millimotors, driving motion via recoil force and buoyancy. Hydrophobic millimotors remain attached to growing bubbles and move by buoyancy alone. Despite their large size, the low-density capsules compress to pass through contractions that would impede and be blocked by solid motors. The sparse structure but relatively large size of the motors enables them to transport significant volumes of liquid using minimal solid mass as a motor support structure.

Lemierre syndrome associated mycotic cavernous sinus thrombosis and carotid aneurysm after COVID-19.

Purpose: The purpose of this article is to report a case of Lemierre syndrome associated mycotic aneurysm of the intracavernous carotid artery leading to cavernous sinus syndrome in an otherwise healthy, young man in the setting of COVID-19 infection. Observations: An 18-year-old, otherwise healthy male athlete developed fever, chills, and headache and was found to be positive for COVID-19 with gram negative bacteremia. While on systemic antibiotic treatment, he developed acute, left-sided, 6th nerve palsy and was found to have bacterial sinusitis, left-sided intracavernous mycotic aneurysm, and cavernous sinus thrombosis on imaging studies. Despite systemic antibiotic and antiplatelet therapy, he developed progressively worsening left-sided ophthalmoplegia and vision decline. He subsequently underwent left internal carotid artery embolization and cervical internal carotid artery sacrifice with excellent outcome. Conclusion and importance: Lemierre syndrome can have atypical presentations and complications, including cavernous sinus thrombosis and mycotic aneurysms. Recognition of signs and symptoms, including progressive multiple cranial neuropathies, can aid in early diagnosis and management, which requires multidisciplinary care tailored to each individual based on risk of intervention.

Corneal Changes and Strategies to Improve Survival of Hypomorphic Collagen VII-Deficient Mice for the Study of Ocular Dystrophic Epidermolysis Bullosa.

Ophthalmic study of collagen CVII hypomorphic mice is uniquely challenging due to the strain's published survival rate to weaning of 24%. Because chronic ocular fibrosis requires time to develop, optimizing the survival rate is of critical importance. In this study, standard husbandry practices were enhanced by the addition of sterilized diet and drug delivery gels, acidified water, irradiated food pellets, cellulose fiber bedding, minimal handling, removal of siblings within 2-3 wk from birth, and a preferred housing location. Survival rates per breeding cycle, sex, weight, and cause of early euthanasia were recorded and analyzed over 43 mo. Overall, 49% of mice survived to weaning and 76% of weaned mice survived to 20 wk of age. Corneal opacities were seen in 65% of mice by 20 wk, but only 10% of eyes showed the sustained opacification that was indicative of fibrosis. Corneal opacities occurred at the same rate as in humans with epidermolysis bullosa. 66% of the mice showed weight loss at 11 wk. Males required early euthanasia 4 times more often than did females. Euthanasia was required for urinary obstruction due to penile prolapse in 88% of males. With our enhanced care protocol, hypomorphic mice in our colony survived at twice the published rate. With this revised husbandry standard, experiments planned with termination endpoints of 14 wk for males and 17 wk for females are more likely to reach completion.

Binder-free mechanochemical metal-organic framework nanocrystal coatings.

The practical applications of metal-organic frameworks (MOFs) usually require their assembly into mechanically robust structures, usually achieved via coating onto various types of substrates. This paper describes a simple, scalable, and versatile mechanochemical technique for producing MOF nanocrystal coatings on various non-prefunctionalised substrates, including ZrO2, carbon cloth, porous polymer, nickel foam, titanium foil and fluorine-doped tin oxide glass. We revealed the detailed mechanisms that ensure the coating's stability, and identified the coating can facilitate the interfacial energy transfer, which allowed the electrocatalysis application of the MOF coating on conductive substrates. We further demonstrated that coatings can be directly generated in a one-pot fashion by ball milling MOF precursors with substrates.

Mechanochemically Synthesised Flexible Electrodes Based on Bimetallic Metal-Organic Framework Glasses for the Oxygen Evolution Reaction.

The melting behaviour of metal-organic frameworks (MOFs) has aroused significant research interest in the areas of materials science, condensed matter physics and chemical engineering. This work first introduces a novel method to fabricate a bimetallic MOF glass, through melt-quenching of the cobalt-based zeolitic imidazolate framework (ZIF) [ZIF-62(Co)] with an adsorbed ferric coordination complex. The high-temperature chemically reactive ZIF-62(Co) liquid facilitates the formation of coordinative bonds between Fe and imidazolate ligands, incorporating Fe nodes into the framework after quenching. The resultant Co-Fe bimetallic MOF glass therefore shows a significantly enhanced oxygen evolution reaction performance. The novel bimetallic MOF glass, when combined with the facile and scalable mechanochemical synthesis technique for both discrete powders and surface coatings on flexible substrates, enables significant opportunities for catalytic device assembly.

Designing Angstrom-Scale Asymmetric MOF-on-MOF Cavities for High Monovalent Ion Selectivity.

Biological ion channels feature angstrom-scale asymmetrical cavity structures, which are the key to achieving highly efficient separation and sensing of alkali metal ions from aqueous resources. The clean energy future and lithium-based energy storage systems heavily rely on highly efficient ionic separations. However, artificial recreation of such a sophisticated biostructure has been technically challenging. Here, a highly tunable design concept is introduced to fabricate monovalent ion-selective membranes with asymmetric sub-nanometer pores in which energy barriers are implanted. The energy barriers act against ionic movements, which hold the target ion while facilitating the transport of competing ions. The membrane consists of bilayer metal-organic frameworks (MOF-on-MOF), possessing a 6 to 3.4-angstrom passable cavity structure. The ionic current measurements exhibit an unprecedented ionic current rectification ratio of above 100 with exceptionally high selectivity ratios of 84 and 80 for K+ /Li+ and Na+ / Li+ , respectively (1.14 Li+ mol m-2 h-1 ). Furthermore, using quantum mechanics/molecular mechanics, it is shown that the combined effect of spatial hindrance and nucleophilic entrapment to induce energy surge baffles is responsible for the membrane's ultrahigh selectivity and ion rectification. This work demonstrates a striking advance in developing monovalent ion-selective channels and has implications in sensing, energy storage, and separation technologies.

Liquid-phase sintering of lead halide perovskites and metal-organic framework glasses.

Lead halide perovskite (LHP) semiconductors show exceptional optoelectronic properties. Barriers for their applications, however, lie in their polymorphism, instability to polar solvents, phase segregation, and susceptibility to the leaching of lead ions. We report a family of scalable composites fabricated through liquid-phase sintering of LHPs and metal-organic framework glasses. The glass acts as a matrix for LHPs, effectively stabilizing nonequilibrium perovskite phases through interfacial interactions. These interactions also passivate LHP surface defects and impart bright, narrow-band photoluminescence with a wide gamut for creating white light-emitting diodes (LEDs). The processable composites show high stability against immersion in water and organic solvents as well as exposure to heat, light, air, and ambient humidity. These properties, together with their lead self-sequestration capability, can enable breakthrough applications for LHPs.

Mechanobiology of Dental Pulp Stem Cells at the Interface of Aqueous-Based Fabricated ZIF8 Thin Film.

The limited knowledge on how biological systems sense and respond to the mechanical properties of metal-organic framework (MOF) thin films is a critical restriction factor for their extensive usage. To bridge this gap, we performed an in vitro study for defining and linking surface characteristics at the interface of the zeolitic imidazolate framework-8 (ZIF8) thin layer to stem cell behavior. First, the physio-mechanical properties of the ZIF8 layer grown on polydopamine (PDA) and tannic acid (TA) layers have been studied. The response of dental pulp stem cells (DPSCs) to different surface states was examined. The results showed that the uniform crystalline microstructure of the ZIF8 on PDA and TA effectively led to the 61- and 388-fold increased surface roughness, 3- and 2.5-fold moderated elastic modulus, almost 3-fold elevated surface free energy, and highly charged surfaces (ζ = -60 mV for TA/ZIF8), respectively. Beyond the inherent bioactivity of the ZIF8 layer, these substrate cues promoted advanced cell adhesion (∼two times) and high proliferation rate. Furthermore, we found a substantial increment in the differentiation efficiency of DPSCs on the ZIF8 layer, in a way that the expression of functional adipocyte (PPARG) and osteoblast (SPP1) markers was, respectively, elevated around 30 000- and 10 000-fold on the TA/ZIF8-coated silicon wafer (SW). Our findings support the impact of fabrication strategy on the biointerface properties of the ZIF8 layer and bring SW/TA/ZIF8 as a robust platform for managing stem cells for biomedical applications.

Hierarchically Porous Biocatalytic MOF Microreactor as a Versatile Platform towards Enhanced Multienzyme and Cofactor-Dependent Biocatalysis.

Metal-organic frameworks (MOFs) have recently emerged as excellent hosting matrices for enzyme immobilization, offering superior physical and chemical protection for biocatalytic reactions. However, for multienzyme and cofactor-dependent biocatalysis, the subtle orchestration of enzymes and cofactors is largely disrupted upon immobilizing in the rigid crystalline MOF network, which leads to a much reduced biocatalytic efficiency. Herein, we constructed hierarchically porous MOFs by controlled structural etching to enhance multienzyme and cofactor-dependent enzyme biocatalysis. The expanded size of the pores can provide sufficient space for accommodated enzymes to reorientate and spread within MOFs in their lower surface energy state as well as to decrease the inherent barriers to accelerate the diffusion rate of reactants and intermediates. Moreover, the developed hierarchically porous MOFs demonstrated outstanding tolerance to inhospitable surroundings and recyclability.

ZIF-8 Modified Polypropylene Membrane: A Biomimetic Cell Culture Platform with a View to the Improvement of Guided Bone Regeneration.

PURPOSE: Despite the significant advances in modeling of biomechanical aspects of cell microenvironment, it remains a major challenge to precisely mimic the physiological condition of the particular cell niche. Here, the metal-organic frameworks (MOFs) have been introduced as a feasible platform for multifactorial control of cell-substrate interaction, given the wide range of physical and mechanical properties of MOF materials and their structural flexibility. RESULTS: In situ crystallization of zeolitic imidazolate framework-8 (ZIF-8) on the polydopamine (PDA)-modified membrane significantly raised surface energy, wettability, roughness, and stiffness of the substrate. This modulation led to an almost twofold increment in the primary attachment of dental pulp stem cells (DPSCs) compare to conventional plastic culture dishes. The findings indicate that polypropylene (PP) membrane modified by PDA/ZIF-8 coating effectively supports the growth and proliferation of DPSCs at a substantial rate. Further analysis also displayed the exaggerated multilineage differentiation of DPSCs with amplified level of autocrine cell fate determination signals, like BSP1, BMP2, PPARG, FABP4, ACAN, and COL2A. Notably, osteogenic markers were dramatically overexpressed (more than 100-folds rather than tissue culture plate) in response to biomechanical characteristics of the ZIF-8 layer. CONCLUSION: Hence, surface modification of cell culture platforms with MOF nanostructures proposed as a powerful nanomedical approach for selectively guiding stem cells for tissue regeneration. In particular, PP/PDA/ZIF-8 membrane presented ideal characteristics for using as a barrier membrane for guided bone regeneration (GBR) in periodontal tissue engineering.

Anterior-segment spectral domain optical coherence tomography in epidermolysis bullosa.

PURPOSE: Assess epidermolysis bullosa (EB)-related corneal pathology using anterior segment optical coherence tomography (AS-OCT) and correlate imaging with clinical metrics in EB patients versus age-matched controls. METHODS: EB patients and controls were recruited during an EB conference (July 2018) and at Tufts Medical Center (June-August 2019). Subjects completed a questionnaire, had best corrected visual acuity (BCVA) tested, and underwent AS-OCT scanning. Stromal and epithelial thickness were measured. Depth, length, and type of the three largest lesions were assessed by a masked examiner using a novel pathology grading system. Multivariate analysis of AS-OCT findings and clinical metrics was performed. RESULTS: 62 EB patients and 60 age-matched controls were enrolled. Mean BCVA was 1.8 lines worse in patients (p < 0.001). Vision loss was associated with increased stromal thickness. Discrete lesions were seen in 60.2% of patient eyes, averaging 1.71 ± 1.75 lesions in patients and 0.14 ± 0.42 in controls (p < 0.001). Mean primary lesion depth was 151.88 ± 97.49 µm in patients. Patients showed significant stromal thickening versus controls and lesions were most common in the periphery and inferiorly. Differences in frequency and duration of abrasions and severity of pain were all statistically and clinically significant in patients versus controls (p < 0.001). CONCLUSIONS: AS-OCT can visualize and quantify differences in the corneas of EB patients compared with age-matched controls. Novel findings include quantification of average depth, length, and severity of discrete lesions, and sparing of the superior quadrant from stromal thickening in EB patients. These results support use of AS-OCT and a questionnaire in clinical trials for new EB therapies.

Dynamic single-site polysulfide immobilization in long-range disorder Cu-MOFs.

The structural transformation of MOFs in a polysulfide electrode process is poorly understood. We report the electrochemical amorphization of Cu3(BTC)2 MOFs in polysulfide electrolyte. We unveil the dynamic single-site polysulfide immobilization at the interconvertible Cu2+/Cu+ cation centres upon polysulfide adsorption and desorption, along with the reversible distortion of the Cu-O square planar unit.

Intermarriage of Halide Perovskites and Metal-Organic Framework Crystals.

This Review examines how the intermarriage of perovskite and metal-organic framework crystals brings new paradigms for material design and functionality. The strategic combination of halide perovskites and metal-organic frameworks (MOFs) has generated a new family of porous composite materials that will enable new applications, including optoelectronic, catalysis, sensing, and data encryption. This Review surveys the current progress of this exciting new area. Fundamental aspects, including perovskite nucleation and growth, heterojunction electron-hole transfer, electronic structure, and luminescence within confined spaces, are highlighted, with suggestions of approaches by which guest confinement within MOFs can be synthetically designed. We further address the underlying principles and discuss the new insights and tools for the manipulation of these composite materials for the development of synthetic microporous semiconducting composites, as well as new strategies for host-guest interfacial engineering.