Conjugated Polyelectrolyte/Bacteria Living Composites in Carbon Paper for Biocurrent Generation.

Successful practical implementation of bioelectrochemical systems (BES) requires developing affordable electrode structures that promote efficient electrical communication with microbes. Recent efforts have centered on immobilizing bacteria with organic semiconducting polymers on electrodes via electrochemical methods. This approach creates a fixed biocomposite that takes advantage of the increased electrode's electroactive surface area (EASA). Here, it is demonstrated that a biocomposite comprising the water-soluble conjugated polyelectrolyte CPE-K and electrogenic Shewanella oneidensis MR-1 can self-assemble with carbon paper electrodes, thereby increasing its biocurrent extraction by ≈6-fold over control biofilms. A ≈1.5-fold increment in biocurrent extraction is obtained for the biocomposite on carbon paper relative to the biocurrent extracted from gold-coated counterparts. Electrochemical characterization revealed that the biocomposite stabilized with the carbon paper more quickly than atop flat gold electrodes. Cross-sectional images show that the biocomposite infiltrates inhomogeneously into the porous carbon structure. Despite an incomplete penetration, the biocomposite can take advantage of the large EASA of the electrode via long-range electron transport. These results show that previous success on gold electrode platforms can be improved when using more commercially viable and easily manipulated electrode materials.

Nontoxic nanopore electroporation for effective intracellular delivery of biological macromolecules.

We present a simple nanopore-electroporation (NanoEP) platform for delivery of nucleic acids, functional protein, and Cas9 single-guide RNA ribonucleoproteins into both adherent and suspension cells with up to 80% delivery efficiency and >95% cell viability. Low-voltage electric pulses permeabilize a small area of cell membrane as a cell comes into close contact with the nanopores. The biomolecule cargo is then electrophoretically drawn into the cells through the nanopores. In addition to high-performance delivery with low cell toxicity, the NanoEP system does not require specialized buffers, expensive materials, complicated fabrication processes, or cell manipulation; it simply consists of a generic nanopore-embedded water-filter membrane and a low-voltage square-wave generator. Ultimately, the NanoEP platform offers an effective and flexible method for universal intracellular delivery.

Nanowire Photoelectrochemistry.

Recent applications of photoelectrochemistry at the semiconductor/liquid interface provide a renewable route of mimicking natural photosynthesis and yielding chemicals from sunlight, water, and air. Nanowires, defined as one-dimensional nanostructures, exhibit multiple unique features for photoelectrochemical applications and promise better performance as compared to their bulk counterparts. This article reviews the use of semiconductor nanowires in photoelectrochemistry. After introducing fundamental concepts essential to understanding nanowires and photoelectrochemistry, the review considers answers to the following questions: (1) How can we interface semiconductor nanowires with other building blocks for enhanced photoelectrochemical responses? (2) How are nanowires utilized for photoelectrochemical half reactions? (3) What are the techniques that allow us to obtain fundamental insights of photoelectrochemistry at single-nanowire level? (4) What are the design strategies for an integrated nanosystem that mimics a closed cycle in artificial photosynthesis? This framework should help readers evaluate the salient features of nanowires for photoelectrochemical applications, promoting the sustainable development of solar-powered chemical plants that will benefit our society in the long run.

Application of microRNA in Human Osteoporosis and Fragility Fracture: A Systemic Review of Literatures.

MicroRNAs (miRNAs) could serve as ideal entry points to the deregulated pathways in osteoporosis due to their relatively simple upstream and downstream relationships with other molecules in the signaling cascades. Our study aimed to give a comprehensive review of the already identified miRNAs in osteoporosis from human blood samples and provide useful information for their clinical application. A systematic literature search for relevant studies was conducted in the Pubmed database from inception to December 2020. We set two essential inclusion criteria: human blood sampling and design of controlled studies. We sorted the results of analysis on human blood samples according to the study settings and compiled the most promising miRNAs with analyzed diagnostic values. Furthermore, in vitro and in vivo evidence for the mechanisms of the identified miRNAs was also illustrated. Based on both diagnostic value and evidence of mechanism from in vitro and in vivo experiments, miR-23b-3p, miR-140-3p, miR-300, miR-155-5p, miR-208a-3p, and miR-637 were preferred candidates in diagnostic panels and as therapeutic agents. Further studies are needed to build sound foundations for the clinical usage of miRNAs in osteoporosis.

Excitation-wavelength-dependent small polaron trapping of photoexcited carriers in α-Fe2O3.

Small polaron formation is known to limit ground-state mobilities in metal oxide photocatalysts. However, the role of small polaron formation in the photoexcited state and how this affects the photoconversion efficiency has yet to be determined. Here, transient femtosecond extreme-ultraviolet measurements suggest that small polaron localization is responsible for the ultrafast trapping of photoexcited carriers in haematite (α-Fe2O3). Small polaron formation is evidenced by a sub-100 fs splitting of the Fe 3p core orbitals in the Fe M2,3 edge. The small polaron formation kinetics reproduces the triple-exponential relaxation frequently attributed to trap states. However, the measured spectral signature resembles only the spectral predictions of a small polaron and not the pre-edge features expected for mid-gap trap states. The small polaron formation probability, hopping radius and lifetime varies with excitation wavelength, decreasing with increasing energy in the t2g conduction band. The excitation-wavelength-dependent localization of carriers by small polaron formation is potentially a limiting factor in haematite's photoconversion efficiency.

Hybrid bioinorganic approach to solar-to-chemical conversion.

Natural photosynthesis harnesses solar energy to convert CO2 and water to value-added chemical products for sustaining life. We present a hybrid bioinorganic approach to solar-to-chemical conversion in which sustainable electrical and/or solar input drives production of hydrogen from water splitting using biocompatible inorganic catalysts. The hydrogen is then used by living cells as a source of reducing equivalents for conversion of CO2 to the value-added chemical product methane. Using platinum or an earth-abundant substitute, α-NiS, as biocompatible hydrogen evolution reaction (HER) electrocatalysts and Methanosarcina barkeri as a biocatalyst for CO2 fixation, we demonstrate robust and efficient electrochemical CO2 to CH4 conversion at up to 86% overall Faradaic efficiency for ≥ 7 d. Introduction of indium phosphide photocathodes and titanium dioxide photoanodes affords a fully solar-driven system for methane generation from water and CO2, establishing that compatible inorganic and biological components can synergistically couple light-harvesting and catalytic functions for solar-to-chemical conversion.

Directed Assembly of Nanoparticle Catalysts on Nanowire Photoelectrodes for Photoelectrochemical CO2 Reduction.

Reducing carbon dioxide with a multicomponent artificial photosynthetic system, closely mimicking nature, represents a promising approach for energy storage. Previous works have focused on exploiting light-harvesting semiconductor nanowires (NW) for photoelectrochemical water splitting. With the newly developed CO2 reduction nanoparticle (NP) catalysts, direct interfacing of these nanocatalysts with NW light absorbers for photoelectrochemical reduction of CO2 becomes feasible. Here, we demonstrate a directed assembly of NP catalysts on vertical NW substrates for CO2-to-CO conversion under illumination. Guided by the one-dimensional geometry, well-dispersed assembly of Au3Cu NPs on the surface of Si NW arrays was achieved with facile coverage tunability. Such Au3Cu NP decorated Si NW arrays can readily serve as effective CO2 reduction photoelectrodes, exhibiting high CO2-to-CO selectivity close to 80% at -0.20 V vs RHE with suppressed hydrogen evolution. A reduction of 120 mV overpotential compared to the planar (PL) counterpart was observed resulting from the optimized spatial arrangement of NP catalysts on the high surface area NW arrays. In addition, this system showed consistent photoelectrochemical CO2 reduction capability up to 18 h. This simple photoelectrode assembly process will lead to further progress in artificial photosynthesis, by allowing the combination of developments in each subfield to create an efficient light-driven system generating carbon-based fuels.

Os(II) phosphors with near-infrared emission induced by ligand-to-ligand charge transfer transition.

Heating of Os3(CO)12 with 6 equiv of 2-(3-(trifluoromethyl)-1H-1,2,4-triazol-5-yl) pyridine (fptzH) in refluxing diethylene glycol monomethyl ether, followed by sequential treatment with stoichiometric Me3NO and addition of PPhMe2, afforded two isomeric mixtures of red-emitting [Os(fptz)2(PPhMe2)2] (1T and 1C), for which the notations T and C stand for the trans and cis-oriented fptz chelates, respectively. Alternatively, preparation of Os(II) complex using a 1:1 mixture of 5,5'-di(trifluoromethyl)-3,3'-di-1,2,4-triazole (dttzH2) and 2,2'-bipyridine (bpy), instead of fptzH, gave isolation of a mononuclear Os(II) complex [Os(bpy)(dttz)(CO)2] (2) in moderate yield. Replacement of CO with PPhMe2 on 2 afforded near-infrared (NIR)-emitting Os(II) complex [Os(bpy)(dttz)(PPhMe2)2] (3). The single-crystal X-ray structural analyses were executed on 1C, 2, and 3 to reveal the structural influence imposed by the various chelates. The photophysical and electrochemical properties were measured and discussed using the results of density functional theory (DFT) and time-dependent DFT calculations. Complex 3 is selected as the dopant to probe its electroluminescent properties by fabrication of the NIR emitting organic light-emitting diodes.

Wearable Microbial Fuel Cells for Sustainable Self-Powered Electronic Skins.

Autonomous energy systems are key to sustainably powering electronic skins. Potential autonomous energy resources include sunlight, human motion, sweat, and body heat, among which the biofuel in human sweat is a most natural and available candidate. In this perspective, we discuss the promise of wearable microbial fuel cells as autonomous power suppliers for electronic skins by using the biofuels in human sweat. In comparison to wearable enzymatic biofuel cells, wearable microbial fuel cells offer easy access, low cost and superior sustainability. We summarize the present achievements and provide our vision toward future research to make wearable microbial fuel cells reliable on-skin power suppliers.

Conjugated Polyelectrolytes: Underexplored Materials for Pseudocapacitive Energy Storage.

Conjugated polyelectrolytes (CPEs) are characterized by an electronically delocalized backbone bearing ionic functionalities. These features lead to properties relevant for use in energy-storing pseudocapacitor devices, including ionic conductivity, water processability, gel-formation, and formation of polaronic species stabilized by electrostatic interactions. In this Perspective, the basis for evaluating the figures of merit for pseudocapacitors is provided, together with the techniques used for their evaluation. The general utility and challenges encountered with neutral conjugated polymers are then discussed. Finally, recent advances on the use of CPEs in pseudocapacitor devices are reviewed. The article is concluded by discussing how their miscibility in aqueous media permits the incorporation of CPEs in living materials that are capable of switching function from extraction of energy from bacterial metabolic pathways to pseudocapacitor energy storage.

Hyperuricemia and Its Association with Osteoporosis in a Large Asian Cohort.

In this paper, we aimed to examine the protective role of hyperuricemia in the prevalence of osteoporosis in a large Asian cohort. A total of 119,037 participants from 29 recruitment centers in Taiwan were enrolled onto our study. Participants with serum uric acid greater than 7.0 mg/dL in men and 6.0 mg/dL in women were classified as the hyperuricemia group whereas the others were the control group. The mean age of all participants was 50; there were 23,114 subjects (19%) with hyperuricemia. Osteoporosis was observed in 8243 (9%) and 1871 (8%) participants in the control and hyperuricemia groups, respectively. After adjusting for confounders, a lower risk of osteoporosis was found in the hyperuricemia group compared with the control group (odds ratio, 0.916; 95% confidence interval, 0.864 to 0.970). A subgroup analysis showed that hyperuricemia was associated with a lower risk of osteoporosis in females, but not in males. Women with serum uric acid greater than 8.0 mg/dL were not associated with a greater risk of osteoporosis. Our study suggests that hyperuricemia decreases the risk of osteoporosis in females, but not in males. The protective role was no longer apparent when the serum uric acid level was greater than 8 mg/dL.

De Novo Approach to Encapsulating Biocatalysts into Synthetic Matrixes: From Enzymes to Microbial Electrocatalysts.

Biocatalysts hold great promise in chemical and electrochemical reactions. However, biocatalysts are prone to inhospitable physiochemical conditions. Encapsulating biocatalysts into a synthetic host matrix can improve their stability and activity, and broaden their operational conditions. In this Review, we summarize the emerging de novo approaches to encapsulating biocatalysts into synthetic matrixes. Here, de novo means that embedding of biocatalysts and construction of matrixes take place simultaneously. We discuss the advantages and limitations of the de novo approach. On the basis of the nature of the biocatalysts and the synthetic frameworks, we specifically focus on two aspects: (1) encapsulation of enzymes (in vitro) in metal-organic frameworks and (2) encapsulation of microbial electrocatalysts (in vivo) on the electrode. For both cases, we discuss how the encapsulation improves biocatalysts' performance (stability, viability, activity, and etc.). We also highlight the benefit of encapsulation in facilitating the transport of charge carriers in microbial electrocatalysis.

Hemoglobin A1c Levels Associated with Age and Gender in Taiwanese Adults without Prior Diagnosis with Diabetes.

Several studies have reported that Hemoglobin A1c (HbA1c) levels increase with age for people without diabetes. However, HbA1c levels associated with age and gender have not been well investigated for Taiwanese adults. The objective of this study was to investigate the sex-specific association between HbA1c levels and age for Taiwanese adults without diabetes. The data were collected from the Taiwan Biobank database with inclusive criteria being participants without diabetes. The association between HbA1c values and age was conducted by linear regression analysis, HbA1c values between sexes were compared by two-sample t-test, and HbA1c levels among age groups were compared using one-way ANOVA. The results showed that HbA1c levels were positively correlated with age, and the levels for males were significantly higher than for females among all participants. However, there was no significantly positive correlation between HbA1c levels and age in males for age group of 50-70 years. The levels of males were significantly higher than females for age groups of 30-39 and 40-49 years. There were significant differences in HbA1c levels among age groups for all participants, males, and females except for the two age groups of 50-59 and 60-70 years in males. Age and gender were important factors affecting HbA1c levels. Our results suggested that the HbA1c cut-point levels for the diagnosis of diabetes should vary by age and gender.

Living Bioelectrochemical Composites.

Composites, in which two or more material elements are combined to provide properties unattainable by single components, have a historical record dating to ancient times. Few include a living microbial community as a key design element. A logical basis for enabling bioelectronic composites stems from the phenomenon that certain microorganisms transfer electrons to external surfaces, such as an electrode. A bioelectronic composite that allows cells to be addressed beyond the confines of an electrode surface can impact bioelectrochemical technologies, including microbial fuel cells for power production and bioelectrosynthesis platforms where microbes produce desired chemicals. It is shown that the conjugated polyelectrolyte CPE-K functions as a conductive matrix to electronically connect a three-dimensional network of Shewanella oneidensis MR-1 to a gold electrode, thereby increasing biocurrent ≈150-fold over control biofilms. These biocomposites spontaneously assemble from solution into an intricate arrangement of cells within a conductive polymer matrix. While increased biocurrent is due to more cells in communication with the electrode, the current extracted per cell is also enhanced, indicating efficient long-range electron transport. Further, the biocomposites show almost an order-of-magnitude lower charge transfer resistance than CPE-K alone, supporting the idea that the electroactive bacteria and the conjugated polyelectrolyte work synergistically toward an effective bioelectronic composite.

Arthroscopic release for frozen shoulder: Does the timing of intervention and diabetes affect outcome?

PURPOSE: To evaluate the effect of timing of arthroscopic release and manipulation under anesthesia for frozen shoulder in patients with diabetes and non-diabetes. METHODS: One hundred and twenty-seven patients with frozen shoulder were included in the study. Each patient was assigned to: 1) one of four groups according to the duration from symptom onset to surgery (group A: ≤3 months; group B: 3-6 months; group C: 6-12 months; group D: >12 months), 2) diabetic or nondiabetic group. The outcomes were measured by shoulder range of motion (ROM), Disabilities of the Arm, Shoulder, and Hand (DASH) score, American Shoulder and Elbow Surgeons (ASES) Shoulder score, the period of pain relief, overall duration of disease, and satisfaction. RESULTS: All the patients got great improvement in shoulder ROM (P < .0001) after arthroscopic surgery, but there was no statistical difference in the pre-operative and post-operative shoulder ROM between the four groups and between diabetic and nondiabetic groups. The overall duration of disease was mean 55.4~68.7 weeks, which demonstrated much shorter disease course compared with nature course. Improvement were also seen in shoulder ROM at one week to one month, and the period of total pain relief was at a mean time of 3.7 to 3.8 weeks. There were higher ASES Shoulder score in group B than in group C (P = 0.02) and higher DASH score in diabetic group in short term follow-up. CONCLUSIONS: Arthroscopic release provides effective and rapid improvements to shoulder motion and function, unrelated to the timing of surgery, in patients with frozen shoulder. The diabetic patients do not have functional outcomes as good as the nondiabetic patient at short-term follow-up.

Single-nanowire photoelectrochemistry.

Photoelectrochemistry is one of several promising approaches for the realization of efficient solar-to-fuel conversion. Recent work has shown that photoelectrodes made of semiconductor nano-/microwire arrays can have better photoelectrochemical performance than their planar counterparts because of their unique properties, such as high surface area. Although considerable research effort has focused on studying wire arrays, the inhomogeneity in the geometry, doping, defects and catalyst loading present in such arrays can obscure the link between these properties and the photoelectrochemical performance of the wires, and correlating performance with the specific properties of individual wires is difficult because of ensemble averaging. Here, we show that a single-nanowire-based photoelectrode platform can be used to reliably probe the current-voltage (I-V) characteristics of individual nanowires. We find that the photovoltage output of ensemble array samples can be limited by poorly performing individual wires, which highlights the importance of improving nanowire homogeneity within an array. Furthermore, the platform allows the flux of photogenerated electrons to be quantified as a function of the lengths and diameters of individual nanowires, and we find that the flux over the entire nanowire surface (7-30 electrons nm(-2) s(-1)) is significantly reduced as compared with that of a planar analogue (∼1,200 electrons nm(-2) s(-1)). Such characterization of the photogenerated carrier flux at the semiconductor/electrolyte interface is essential for designing nanowire photoelectrodes that match the activity of their loaded electrocatalysts.