Sculpting liquid metal stabilized interfaces: a gateway to liquid electronics.

Liquid electronics have potential applications in soft robotics, printed electronics, and healable electronics. The intrinsic shortcomings of solid-state electronics can be offset by liquid conductors. Alloys of gallium have emerged as transformative materials for liquid electronics owing to their intrinsic fluidity, conductivity, and low toxicity. However, sculpting liquid metal or its composites into a 3D architecture is a challenging task. To tackle this issue, herein, we explored the interfacial chemistry of metal ions and tannic acid (TA) complexation at a liquid-liquid interface. First, we established that an MIII-TA network at the liquid-liquid interface could structure liquid in liquid by jamming the interfacial film. The surface coverage of the droplet largely depends on the concentration of metal ions, oxidation state of metal ions and pH of the surrounding environment. Further extending the approach, we demonstrated that TA-functionalized gallium nanoparticles (Ga NPs) can also sculpt liquid droplets in the presence of transition metal ions. Finally, a mold-based free-standing 3D architecture is obtained using the interfacial reaction and interfacial crowding of a metal-phenolate network. Conductivity measurement reveals that these liquid constructs can be used for low-voltage electronic applications, thus opening the door for liquid electronics.

Harnessing Environmental Sensitivity in SnSe-Based Metal-Semiconductor-Metal Devices: Unveiling Negative Photoconductivity for Enhanced Photodetector Performance and Humidity Sensing.

The extreme sensitivity of 2D-layered materials to environmental adsorbates, which is typically seen as a challenge, is harnessed in this study to fine-tune the material properties. This work investigates the impact of environmental adsorbates on electrical properties by studying metal-semiconductor-metal (MSM) devices fabricated on CVD-synthesized SnSe flakes. The freshly prepared devices exhibit positive photoconductivity (PPC), whereas they gradually develop negative photoconductivity (NPC) after being exposed to an ambient environment for ∼1 day. While the photodetectors based on positive photoconductivity exhibit a responsivity and detectivity of 6.1 A/W and 5.06 × 108 Jones, the same for the negative photoconductivity-based photodetector reaches up to 36.3 A/W and 1.49 × 109 Jones, respectively. In addition, the noise-equivalent power of the NPC photodetector decreases by 300 times as compared to the PPC device, which implies a prominent detection capability of the NPC device against weak photo signals. To substantiate the hypothesis that negative photoconductivity stems from the photodesorption of water and oxygen molecules on the dangling bonds of SnSe flakes, the flakes are etched along the most active planes (010) with a focused laser beam in an inert environment, which enhances responsivity by 43%, supporting negative photoconductivity linked to photodesorption. Furthermore, the humidity-dependent dark current variation of the NPC photodetectors is used to design a humidity sensor for human respiration monitoring with faster response and recovery times of 0.72 and 0.68 s, respectively. These findings open up the possibility of tuning the photoelectrical response of layered materials in a facile manner to develop future sensors and optoelectronic multifunctional devices.

Phosphorus-Doped Nickel Oxide Micro-Supercapacitor: Unleashing the Power of Energy Storage for Miniaturized Electronic Devices.

For an uninterrupted self-powered network, the requirement of miniaturized energy storage device is of utmost importance. This study explores the potential utilization of phosphorus-doped nickel oxide (P-NiO) to design highly efficient durable micro-supercapacitors. The introduction of P as a dopant serves to enhance the electrical conductivity of bare NiO, leading to 11-fold augmentation in volumetric capacitance to 841.92 Fcm-3 followed by significant enhancement of energy and power density from 6.71 to 42.096 mWhcm-3 and 0.47 to 1.046 Wcm-3, respectively. Theoretical calculations used to determine the adsorption energy of OH- ions, revealing higher in case of bare NiO (1.52 eV) as compared to phosphorus-doped NiO (0.64 eV) leading to high electrochemical energy storage performance. The as-designed micro-supercapacitor (MSC) device demonstrates a facile integration with the photovoltaic system for renewable energy storage and smooth transfer to external loads for enlightening the blue LED for ≈1 min. The choice of P-NiO/Ni not only contributes to cost reduction but also ensures minimal lattice mismatch at the interface facilitating high durability up to 15 K cycles along with capacitive retention of ≈100% and coulombic efficiency of 93%. Thus, the heterostructure unveils the possibilities of exploring miniaturized energy storage devices for portable electronics.

Porous Carbon Template Decorated with MOF-Driven Bimetallic Phosphide: A Suitable Heterostructure for the Production of Uninterrupted Green Hydrogen via Renewable Energy Storage Device.

Water splitting via an uninterrupted electrochemical process through hybrid energy storage devices generating continuous hydrogen is cost-effective and green approach to address the looming energy and environmental crisis toward constant supply of hydrogen fuel in fuel cell driven automobile sector. The high surface area metal-organic framework (MOF) driven bimetallic phosphides (ZnP2 @CoP) on top of CNT-carbon cloth matrix is utilized as positive and negative electrodes in energy storage devices and overall water splitting. The as-prepared positive electrode exhibits excellent specific capacitances/capacity of 1600 F g-1 /800 C g-1 @ 1A g-1 and the corresponding hybrid device reveals an energy density of 83.03 Wh kg-1 at power density of 749.9 W kg-1 . Simultaneously, the electrocatalytic performance of heterostructure shows overpotentials of 90 mV@HER and 204 mV@OER at current density of 10 and 20 mA cm-2 , respectively in alkaline electrocatalyzer. Undoubtedly, it shows overall water splitting with low cell voltage of 1.53 V@10 mA cm-2 having faradic and solar-to-hydrogen conversion efficiency of 98.81% and 9.94%, respectively. In addition, the real phase demonstration of the overall water-splitting is performed where the electrocatalyzer is connected with a series of hybrid supercapacitor devices powered up by the 6 V standard silicon solar panel to produce uninterrupted green H2 .

Universal Single-Step Approach to the Immobilization of Cyclodextrins in a Supercritical Medium for Capturing Drug, Dye, and Metal Nanoclusters.

By utilizing nanoreactor-like structures, the immobilization of macromolecules such as calixarenes and cyclodextrins (CD) with bucket-like structures provides new possibilities for engineered surface-molecule systems. The practical use of any molecular system depends on the availability of a universal procedure for immobilizing molecules with torus-like structures on various surfaces while maintaining identical operating parameters. There are currently several steps, including toxic solvent-based approaches using modified ß-CD to covalently attach to surfaces with multistep reactions. However, the existing multistep process results in molecular orientation, restricts the accessibility of the hydrophobic barrel of ß-CD's for practical use, and is effectively unable to use the surfaces immobilized with ß-CD for a variety of applications. In this study, it was demonstrated that ß-CD attached to the oxide-based semiconductor and metal surfaces through a condensation reaction between the hydroxyl-terminated oxide-based semiconductor/metal oxide and ß-CD in supercritical carbon dioxide (SCCO2) as a medium. The primary benefit of SCCO2-assisted grafting of unmodified ß-CD on various oxide-based metal and semiconductor surfaces is that it is a simple, efficient, one-step process and that it is ligand-free, scalable, substrate-independent, and uses minimal energy. Various physical microscopy and chemical spectroscopic methods were used to analyze the grafted ß-CD oligomers. The application of the grafted ß-CD films was demonstrated by the immobilization of rhodamine B (RhB), a dye, and dopamine, a drug. The in situ nucleation and growth of silver nanoclusters (AgNCs) in the molecular systems were studied for antibacterial and tribological properties by utilizing the guest-host interaction ability of ß-CD.

Five Novel Silver-Based Coordination Polymers as Photoluminescent Sensing Platforms for the Detection of Nitrobenzene.

Nitrobenzene (NB) is a highly toxic chemical and a cause for concern to human health and the environment. Hence, it is worth designing new efficient and robust sensing platforms for NB. In this study, we present three newly synthesized luminescent silver cluster-based coordination polymers, {[Ag10 (StBu)6 (CF3 COO)4 (hpbt)] (DMAc)2 (CH3 CN)2 }n (hpbt=N,N,N',N'N",N"-hexa(pyridine-4-yl)benzene-1,3,5-triamine), [Ag12 (StBu)6 (CF3 COO)6 (bpva)3 ]n (bpva=9,10-Bis(2-(pyridin-4-yl)vinyl)anthracene), and {[Ag12 (StBu)6 (CF3 COO)6 (bpb)(DMAc)2 (H2 O)2 ] (DMAc)2 }n (bpb=1,4-Bis(4-pyridyl)benzene) composed of Ag10 , Ag12 and Ag12 cluster cores, respectively, connected by multidentate pyridine linkers. In addition, two new luminescent polymorphic silver(I)-based coordination polymers, [Ag(CF3 COO)(dpa)]n (dpa=9,10-di(4-pyridyl)anthracene) referred to as Agdpa (H) and Agdpa (R), where H and R denote hexagon- and rod-like crystal shapes, respectively, have been prepared. The coordination polymers exhibit highly sensitive luminescence quenching effects to NB, attributed to the π-π stacking interactions between the polymers and NB as well as the electron-withdrawing character of NB.

Silver cluster-assembled materials for label-free DNA detection.

Herein, we report two newly synthesized silver cluster-assembled materials (SCAMs), [Ag14(StBu)10(CF3COO)4(bpa)2]n (bpa = 1,2-bis(4-pyridyl)acetylene) and [Ag12(StBu)6(CF3COO)6(bpeb)3]n (bpeb = 1,4-bis(pyridin-4-ylethynyl)benzene) composed of Ag14 and Ag12 chalcogenolate cluster cores, respectively, bridged by acetylenic bispyridine linkers. The linker structures and electrostatic interaction between positively charged SCAMs and negatively charged DNA confer the SCAMs with the ability to suppress the high background fluorescence of single-stranded (ss) DNA probes with SYBR Green I nucleic acid stain, leading to high signal-to-noise ratio for label-free target DNA detection.

Benefits and Biosafety of Use of 3D-Printing Technology for Titanium Biomedical Implants: A Pilot Study in the Rabbit Model.

BACKGROUND: Titanium has been used in osteosynthesis for decades and its compatibility and safety is unquestioned. Studies have shown that there is release and collection of titanium in the organ systems with little note of toxicity. The gold standard is considered to be titanium osteosynthesis plate produced by milling methods. The use of customized titanium plates produced with 3D printing, specifically direct metal laser sintering, have found increasing use in recent years. It is unknown how much titanium is released in these printed titanium implants, which is known to be potentially porous, depending on the heat settings of the printer. We hypothesize that the amount of titanium released in printed titanium implants may be potentially more or equal compared to the gold standard, which is the implant produced by milling. METHODS: We studied the biosafety of this technology and its products by measuring serum and organ titanium levels after implantation of 3D-printed versus traditionally fabrication titanium plates and screws in a pilot study using the rabbit model. A total of nine rabbits were used, with three each in the control, milled and printed titanium group. The animals were euthanized after six months. Serum and organs of the reticuloendothelial system were harvested, digested and assayed for titanium levels. RESULTS: Organ and serum titanium levels were significantly higher in rabbit subjects implanted with titanium implants (milled and printed) compared to the control group. However, there was no significant difference in organ and serum titanium levels of subjects implanted with milled and traditionally fabricated titanium implants. CONCLUSIONS: The biosafety of use of 3D-printed titanium implants and traditionally fabricated titanium implants are comparable. With this in mind, 3D-printed custom implants can not only replace, but will very possibly surpass traditionally fabricated titanium implants in the mode and extent of use.

Paraneoplastic Dermatomyositis in a Case of Gallbladder Signet Ring Cell Carcinoma.

Dermatomyositis (DM), as a paraneoplastic presentation, is rare, though the incidence of malignancies in patients with DM is very high. While it has been reported with a wide range of cancers, association with gallbladder carcinoma is uncommon. Furthermore, signet ring cell carcinoma detected in the metastasis presumably from our patient's gallbladder mass is itself a rare and highly malignant variant of gallbladder adenocarcinoma. Thus, this association can be considered to be a very novel finding.  We describe the case of a 64-year-old Indian man who presented with cervical lymph node swelling concurrent with facial rashes, periorbital oedema, nasal regurgitation, dysphagia and weakness in his limbs. The presence of characteristic Gottron's papules and shawl-like truncal rash on examination led to the diagnosis of DM. Fine needle aspiration cytology (FNAC) of the cervical lymph nodes revealed metastatic signet ring cells, and contrast-enhanced CT (CECT) scan of the abdomen showed a significant gallbladder mass with liver infiltration, thus confirming the underlying association.

Bacteriorhodopsin Enhances Efficiency of Perovskite Solar Cells.

Recently, halide perovskites have upstaged decades of solar cell development by reaching power conversion efficiencies that surpass the performance of polycrystalline silicon. The efficiency improvement in the perovskite cells is related to repeated recycling between photons and electron-hole pairs, reduced recombination losses, and increased carrier lifetimes. Here, we demonstrate a novel approach toward augmenting the perovskite solar cell efficiency by invoking the Förster Resonance Energy Transfer (FRET) mechanism. FRET occurs in the near-field region as the bacteriorhodopsin (bR) protein, and perovskite has similar optical gaps. Titanium dioxide functionalized with the bR protein is shown to accelerate the electron injection from excitons produced in the perovskite layer. FRET predicts the strength of long-range excitonic transport between the perovskite and bR layers. Solar cells incorporating TiO2/bR layers are found to exhibit much higher photovoltaic performance as compared to baseline cells without bR. These results open the opportunity to develop a new class of bioperovskite solar cells with improved performance and stability.

Full Dissolution of the Whole Lithium Sulfide Family (Li2 S8 to Li2 S) in a Safe Eutectic Solvent for Rechargeable Lithium-Sulfur Batteries.

The lithium-sulfur battery is an attractive option for next-generation energy storage owing to its much higher theoretical energy density than state-of-the-art lithium-ion batteries. However, the massive volume changes of the sulfur cathode and the uncontrollable deposition of Li2 S2 /Li2 S significantly deteriorate cycling life and increase voltage polarization. To address these challenges, we develop an ϵ-caprolactam/acetamide based eutectic-solvent electrolyte, which can dissolve all lithium polysulfides and lithium sulfide (Li2 S8 -Li2 S). With this new electrolyte, high specific capacity (1360 mAh g-1 ) and reasonable cycling stability are achieved. Moreover, in contrast to conventional ether electrolyte with a low flash point (ca. 2 °C), such low-cost eutectic-solvent-based electrolyte is difficult to ignite, and thus can dramatically enhance battery safety. This research provides a new approach to improving lithium-sulfur batteries in aspects of both safety and performance.

The Translational and Rotational Dynamics of a Colloid Moving Along the Air-Liquid Interface of a Thin Film.

This study examines the translation and rotation of a spherical colloid straddling the (upper) air/liquid interface of a thin, planar, liquid film bounded from below by either a solid or a gas/liquid interface. The goal is to obtain numerical solutions for the hydrodynamic flow in order to understand the influence of the film thickness and the lower interface boundary condition. When the colloid translates on a film above a solid, the viscous resistance increases significantly as the film thickness decreases due to the fluid-solid interaction, while on a free lamella, the drag decreases due to the proximity to the free (gas/liquid) surface. When the colloid rotates, the contact line of the interface moves relative to the colloid surface. If no-slip is assumed, the stress becomes infinite and prevents the rotation. Here finite slip is used to resolve the singularity, and for small values of the slip coefficient, the rotational viscous resistance is dominated by the contact line stress and is surprisingly less dependent on the film thickness and the lower interface boundary condition. For a colloid rotating on a semi-infinite liquid layer, the rotational resistance is largest when the colloid just breaches the interface from the liquid side.

Carbon Quantum Dots Grafted Antifouling Membranes for Osmotic Power Generation via Pressure-Retarded Osmosis Process.

Osmotic power generated by pressure-retarded osmosis (PRO) has attracted global attention as a clean, abundant and renewable energy resource. However, the substrates of PRO membranes are particularly prone to fouling because of their direct contact with various foulants in raw water. This leads to a significant decline in power density and impedes the commercialization of PRO technology. In this work, a facile surface modification method has been developed to obtain a new type of nanoparticle functionalized antifouling PRO membranes. Carbon quantum dots (CQDs), with an average size around 3.2 nm, are fabricated from citric acid via a simple method. Subsequently, they are immobilized onto the polydopamine (PDA) layer grafted on the substrate surface of poly(ether sulfone) (PES) membranes via covalent bonding. The bacteria diffusion tests show that the CQD modified PRO membranes possess much enhanced antibacterial activity and antibiofouling propensity. The continuous PRO operations at 15 bar also confirm that the CQD modified membranes exhibit a much higher power density (11.0 vs 8.8 W/m2) and water recovery after backwash (94 vs 89%) than the unmodified ones. This study may open up a new avenue in the fabrication of nanostructure functionalized polymeric membranes for wastewater treatment and osmotic power generation.

The potential of hybrid forward osmosis membrane bioreactor (FOMBR) processes in achieving high throughput treatment of municipal wastewater with enhanced phosphorus recovery.

Extensive research in recent years has explored numerous new features in the forward osmosis membrane bioreactor (FOMBR) process. However, there is an aspect, which is revolutionary but not yet been investigated. In FOMBR, FO membrane shows high rejection for a wide range of soluble contaminants. As a result, hydraulic retention time (HRT) does not correctly reflect the nominal retention of these dissolved contaminants in the bioreactor. This decoupling of contaminants retention time (CRT, i.e. the nominal retention of the dissolved contaminants) from HRT endows FOMBR a potential in significantly reducing the HRT for wastewater treatment. In this work, we report our results in this unexplored treatment potential. Using real municipal wastewater as feed, both a hybrid microfiltration-forward osmosis membrane bioreactor (MF-FOMBR) and a newly developed hybrid biofilm-forward osmosis membrane bioreactor (BF-FOMBR) achieved high removal of organic matter and nitrogen under HRT of down to 2.0 h, with significantly enhanced phosphorus recovery capacities. In the BF-FOMBR, the used of fixed bed biofilm not only obviated the need of additional solid/liquid separation (e.g. MF) to extract the side-stream for salt accumulation control and phosphorus recovery, but effectively quarantined the biomass from the FO membrane. The absence of MF in the side-stream further allowed suspended growth to be continuously removed from the system, which produced a selection pressure for the predominance of attached growth. As a result, a significant reduction in FO membrane fouling (by 24.7-54.5%) was achieved in the BF-FOMBR due to substantially reduced bacteria deposition and colonization.

Towards high through-put biological treatment of municipal wastewater and enhanced phosphorus recovery using a hybrid microfiltration-forward osmosis membrane bioreactor with hydraulic retention time in sub-hour level.

This work uncovers an important feature of the forward osmosis membrane bioreactor (FOMBR) process: the decoupling of contaminants retention time (CRT) and hydraulic retention time (HRT). Based on this concept, the capability of the hybrid microfiltration-forward osmosis membrane bioreactor (MF-FOMBR) in achieving high through-put treatment of municipal wastewater with enhanced phosphorus recovery was explored. High removal of TOC and NH4(+)-N (90% and 99%, respectively) was achieved with HRTs down to 47min, with the treatment capacity increased by an order of magnitude. Reduced HRT did not affect phosphorus removal and recovery. As a result, the phosphorus recovery capacity was also increased by the same order. Reduced HRT resulted in increased system loading rates and thus elevated concentrations of mixed liquor suspended solids and increased membrane fouling. 454-pyrosequecing suggested the thriving of Bacteroidetes and Proteobacteria (especially Sphingobacteriales Flavobacteriales and Thiothrix members), as well as the community succession and dynamics of ammonium oxidizing and nitrite oxidizing bacteria.

Direct and complete phosphorus recovery from municipal wastewater using a hybrid microfiltration-forward osmosis membrane bioreactor process with seawater brine as draw solution.

We report a hybrid microfiltration-forward osmosis membrane bioreactor (MF-FOMBR) for direct phosphorus recovery from municipal wastewater in the course of its treatment. In the process, a forward osmosis (FO) membrane and a microfiltration (MF) membrane are operated in parallel in a bioreactor. FO membrane rejects the nutrients (e.g., PO4(3-), Ca(2+), Mg(2+), etc.) and results in their enrichment in the bioreactor. The nutrients are subsequently extracted via the MF membrane. Phosphorus is then recovered from the nutrients enriched MF permeate via precipitation without addition of an external source of calcium or magnesium. The use of seawater brine as a draw solution (DS) is another novel aspect of the system. The process achieved 90% removal of total organic carbon and 99% removal of NH4(+)-N. 97.9% of phosphate phosphorus (PO4(3-)-P) was rejected by the FO membrane and enriched within the bioreactor. >90% phosphorus recovery was achieved at pH 9.0. The precipitates were predominantly amorphous calcium phosphate with a phosphorus content of 11.1-13.3%. In principal, this process can recover almost all the phosphorus, apart from that assimilated by bacteria for growth. Global evaluation showed an overall phosphorus recovery of 71.7% over 98 days.

An unusual presentation of neurofibroma masquerading as a vascular hamartoma, post-iatrogenic intervention.

Neurofibroma is a localized discrete mass of benign nerve sheath tumour in the peripheral nervous system. Mostly present as skin lesions. Solitary neurofibroma may occur in deep soft tissue or subcutaneous plane in rare cases associated with syndromes like NF1. The neurofibroma most commonly present as skin lesions as isolated soft papules or nodules arising in any cutaneous site. Present case depicts unusual presentation of a neurofibroma as a vascular hamartoma post an iatrogenic intervention.

Enzymatic hydrolysis of water hyacinth biomass for the production of ethanol: optimization of driving parameters.

An efficient conversion of lignocellulose into fermentable sugars is a key step in producing bioethanol in a cost effective and eco-friendly manner. Alternative source like water hyacinth biomass (WHB) (Eichhornia crassipes) may be used as a supplement for the routine feedstocks. The enzyme loading for optimum yield of total reducing sugar was investigated and the enzyme-substrate interaction optimised. The maximal reducing sugar and xylose yield was obtained using cellulase and xylanase loading of 46.12 and 289.98 U/g and 2.26% (w/v) substrate loading. The efficiencies of ethanol production from the WHB hydrolysate are very less and the maximal ethanol yield was 3.4969 g/L when Pichia stiptis was used, followed by 3.4496 and 3.1349 g/L for Candida shehatae and Saccharomyces cerevisiae.

Adenocarcinoma in retroperitoneal teratoma.

We report a rare case of adenocarcinoma in retroperitoneal teratoma in a 38 year old female patient who attended surgical OPD with complaints of dragging pain and heaviness in left lumbar region. Straight x-ray abdomen showed few irregular calcifications in left lumbar region. USG and CT showed it to be adrenal tumor and retroperitoneal teratoma respectively. Excised specimen confirmed it as mucin secreting adenocarcinoma in a case of retroperitoneal teratoma.

Anesthetic management of a patient with sickle ß thalassemia.

Sickle cell disease is a congenital condition and its most common clinical manifestation is anemia due to chronic hemolysis. Persistent and accelerated hemolysis associated with multiple transfusions is a recognized risk factor for the development of cholelithiasis. The occurrence of gallstones is one of the most important manifestations of sickle cell disease in the digestive tract. Most gallstones are pigmented and characteristically occur at younger ages and the prevalence of cholelithiasis increases progressively with age, affecting 50% of young adults. Cholecystectomy is the most common surgical procedure performed in sickle cell disease patients. Anesthesia in this population of patients for major surgeries deserves special attention due to various complications particularly silent infarctions of end organs are common. We are reporting a 14-year-old girl diagnosed with sickle cell anemia and ß(+) thalassemia with cholelithiasis went for cholecystectomy under general anesthesia. Although the patient has both ß(+) thalassemia and sickle cell disease component, the latter is of more concern for anesthesia.