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We analyze the electroosmotic flow (EOF) of an electrolytic solution in a polymer coated capillary electrophoresis tube. The polymeric density, charge, thickness, and the capillary tube charge vary as a function of pH and produce a non-trivial modulation of the EOF, including a flow reversal at acid pH conditions. By means of a theoretical argument and numerical simulations, we recover the experimental curve for the EOF, providing a firm approach for predictive analysis of electroosmosis under different polymeric coating conditions. A proposed application of the approach is to determine the near-wall charge of the coating to be used for further quantitative analysis of the electroosmotic flow and mobility. [ABSTRACT FROM AUTHOR]

We assess the feasibility of using struvite as a component of a fire-extinguishing powder agent. A fine-particle crystalline MgNH4PO4⋅6H2O hydrate (struvite) has been synthesized in the presence of different surfactants. We have optimized conditions for the preparation of a fine-particle crystalline hydrate so as to exclude a comminution step, without distorting its crystal structure. The thermal decomposition of the crystalline hydrates synthesized in the presence of the surfactants has been shown to be accompanied by a considerable heat absorption, which can be used to lower the temperature of a fire source. [ABSTRACT FROM AUTHOR]

In discrete tomography, ghosts represent indeterminate locations of a reconstruction when there is insufficient projection information to admit a unique solution. Our previous work presented maximal ghosts, which are tilings of 2 N connected points of ± 1 values with zero line sums over N directions. These directions are given by the recursion v n + 1 = v n + 2 ϵ n + 1 v n - 1 with ϵ n + 1 ∈ { - 1 , 1 } . By including one additional direction, interior points are cancelled leaving only a thin boundary of ghost errors. Here, we show that a simple modification to this recursion is not possible to generate boundary ghosts in three dimensions. Rather, we present a combination of three different recurrences to achieve this goal. We derive results pertaining to the connectivity, size and structure of these shapes. [ABSTRACT FROM AUTHOR]

Background Long-term health sequelae of coronavirus disease 2019 (COVID-19) may be multiple but have thus far not been systematically studied. Methods All patients discharged after COVID-19 from the Radboud University Medical Center, Nijmegen, the Netherlands, were consecutively invited to a multidisciplinary outpatient facility. Also, nonadmitted patients with mild disease but with symptoms persisting >6 weeks could be referred by general practitioners. Patients underwent a standardized assessment including measurements of lung function, chest computed tomography (CT)/X-ray, 6-minute walking test, body composition, and questionnaires on mental, cognitive, health status, and quality of life (QoL). Results 124 patients (59 ± 14 years, 60% male) were included: 27 with mild, 51 with moderate, 26 with severe, and 20 with critical disease. Lung diffusion capacity was below the lower limit of normal in 42% of discharged patients. 99% of discharged patients had reduced ground-glass opacification on repeat CT imaging, and normal chest X-rays were found in 93% of patients with mild disease. Residual pulmonary parenchymal abnormalities were present in 91% of discharged patients and correlated with reduced lung diffusion capacity. Twenty-two percent had low exercise capacity, 19% low fat-free mass index, and problems in mental and/or cognitive function were found in 36% of patients. Health status was generally poor, particularly in the domains functional impairment (64%), fatigue (69%), and QoL (72%). Conclusions This comprehensive health assessment revealed severe problems in several health domains in a substantial number of ex–COVID-19 patients. Longer follow-up studies are warranted to elucidate natural trajectories and to find predictors of complicated long-term trajectories of recovery. [ABSTRACT FROM AUTHOR]

Herein, we present the structural and electrical properties of layered titanate, the precursor of an ideal two-dimensional (2D) nanosheet. A K0.8Ti1.73Li0.27O4 (KTLO) sample was synthesized by the flux method to maximize the area of the, relative to that under conventional methods, and to assess the oriented growth direction of the synthesis process. The structure of the protonated layered titanate H1.07Ti1.73O4 (HTO), obtained by replacing the intercalated K+ cations with H3O+, was analyzed to observe the effect of variables in the acid exchange process. Notably, the electrical characteristics of both layered titanates in the bulk state have not been previously reported. Herein, we measured the dielectric permittivity of bulk layered titanates without thermal treatment, which was observed to be lower than that of the nanosheet form. Additionally, these titanates were successfully exfoliated into large single-layer nanosheets. Overall, these results provide insights to clarify the properties of layered materials prior to nanosheet exfoliation. [ABSTRACT FROM AUTHOR]

Spherical silica is a fundamentally important material with uses across a wide and diverse range of areas. However, the synthetic routes to producing spherical silica—typically Stöber processes—are inherently unsustainable and environmentally damaging. Petrochemical surfactants, alcoholic solvents, and ammonium hydroxide, which are commonly used, each have their own associated environmental problems. Demand is growing to find new, more sustainable ways, to synthesise spherical silica. Bioinspired and biomimetic silica, produced using knowledge learned from natural silica production methods such as biomineralisation, is an ever-growing field of research, that provides a possible route to more sustainable industrial silica production. Biomolecules can be used to shape and form spherical silica instead of petrochemical surfactants. Water-based chemistries can be used instead of alcohol solvents and ammonium hydroxide. This review establishes the parallels between the natural silica biomineralisation process and Stöber processes and focuses on the physicochemical properties necessary for biomolecules to synthesise spherical silica. Recent biomolecule-based syntheses are highlighted, and an outlook is given on further developments in the field. [ABSTRACT FROM AUTHOR]

The lepidocrocite-type H1.07Ti1.73O4 microsized structures with a tap density of 0.88 g·cm−3 were prepared through the ion exchange method with K0.8Li0.27Ti1.73O4 powder as the precursor, and they exhibited good rate performance and outstanding cycle stability as an anode material for lithium ion batteries (LIB). The ion exchange method provides favorable conditions for H1.07Ti1.73O4 as an anode electrode material for LIBs. X-ray photoelectron spectroscopy (XPS) result demonstrates the existence of defects in the nonstoichiometric H1.07Ti1.73O4, which have a beneficial effect on the LIB performance. The electrochemical performance test proves that the half-cell with microsized H1.07Ti1.73O4 as the anode electrode can maintain a specific capacity of 129.5 mAh·g−1 after 1100 cycles and 101 mAh·g−1 after 3000 long cycles at high current densities of 2.0 and 5.0 A·g−1, respectively. In addition, the small volume change rate of 3.6% in H1.07Ti1.73O4 during Li ion insertion was confirmed by real-time in situ transmission electron microscopy (TEM). The LiFePO4||H1.07Ti1.73O4 full battery exhibits a long-term cycling stability with a specific capacity of 73.8 mAh·g−1 at a current density of 500 mA·g−1 after 200 cycles. [ABSTRACT FROM AUTHOR]

Summary: A suitable electrode or active material is one of the promising ways to boost supercapacitors' efficiency. The right properties of the electrode materials will enhance the performance of the supercapacitors. New electrode materials such as biomass‐derived carbon, mesoporous materials, and transition metal nitrides have been studied as potential substitutes for the most common electrode material, activated carbon. This review discusses the recent (5 years) progress of the electrode materials in supercapacitors compiling the literature from 2016 to 2020. The overview of design (structures), recent developments, and challenges of the new electrode materials are presented in this review with considerations on their electrochemical performance in supercapacitors. [ABSTRACT FROM AUTHOR]

Beamline I22 at Diamond Light Source is dedicated to the study of soft‐matter systems from both biological and materials science. The beamline can operate in the range 3.7 keV to 22 keV for transmission SAXS and 14 keV to 20 keV for microfocus SAXS with beam sizes of 240 µm × 60 µm [full width half‐maximum (FWHM) horizontal (H) × vertical (V)] at the sample for the main beamline, and approximately 10 µm × 10 µm for the dedicated microfocusing platform. There is a versatile sample platform for accommodating a range of facilities and user‐developed sample environments. The high brilliance of the insertion device source on I22 allows structural investigation of materials under extreme environments (for example, fluid flow at high pressures and temperatures). I22 provides reliable access to millisecond data acquisition timescales, essential to understanding kinetic processes such as protein folding or structural evolution in polymers and colloids. [ABSTRACT FROM AUTHOR]

Layered materials are promising candidates to serve for thermal insulation coatings because of their low out‐of‐plane thermal conductivity. The thin film preparation of the layered materials in layer‐by‐layer fashion can be realized by several solution processes. However, the layered materials suffer low thermal stability after the solution processes. Herein, we report a strategy to improve the thermal stability of the layered materials processed in solution. In this work, we studied the thermal stability of the lepidocrocite‐type titanate with various interlayer ions (Li+, Na+, K+, and Cs+) at elevated temperatures. We proved that the thermal stability of the titanate increased with the increase of the ionic radius. The Cs+ intercalated titanate can remain in its layered structure up to 1000°C, while the Li+ interacted titanate loses its structural stability at ~280°C. Our work suggests that increasing the size of the interlayer ions is an effective strategy to enhance the structural stability of layered titanates. [ABSTRACT FROM AUTHOR]

Insertion type material has been attracted plenty of attentions as the anode of sodium ion batteries (SIBs) due to the low volume change induced long cycle stability. H1.07Ti1.73O4 (HTO), a two‐dimensional layered material, is a new insertion type anode material for SIBs reported in this study. Layered HTO composites were decorated with rGO nanosheets via an electrostatic assembly method followed by hydrothermal treatment. When adapted as the anode material of SIBs, HTO@rGO composite exhibits an enhanced sodium ion storage behavior, including high rate capability and long cycle stability. It can deliver high capacities of 142.8 and 66.7 mA h g−1 at 100 and 10 000 mA g−1, respectively. Moreover, it can keep a capacity of 75.1 mA h g−1 at 5 A g−1 after even 5000 cycles, corresponding to a high capacity retention of 70.8% (0.0058% capacity decay per cycle). HTO exhibits a small volume expansion of 19.6% by in‐situ transmission electron microscopy (in‐situ TEM). The diffusion coefficient of sodium ions is increased from 1.77 × 10−14 cm2 s−1 in HTO composites to 4.80 × 10−14 cm2 s−1 in HTO@rGO composites. Our designed and synthesized HTO@rGO provides a new route for high rate and long cycle stable SIBs anode materials. [ABSTRACT FROM AUTHOR]

The dissolution kinetics of different varieties of natural gypsum samples with different porosity and content of insoluble impurities are experimentally investigated under unsaturated conditions. The main goal of this work is to verify whether and how the petrophysical and petrographic nature of gypsum influence its dissolution rate. Gypsum samples were taken from Priabonian (Ludian) and Lutetian formations located in the north-eastern suburbs of Paris, where the development of sinkholes due to gypsum dissolution is a common phenomenon. Experiments using the rotating disk technique allow us to determine the kinetic rate model parameters of each sample in pure water following the empirical rate expression derived from mixed kinetic theory. The kinetic order n shows a dispersion around a mean value n = 1.2 and k, the pure dissolution rate coefficient varies according to the facies and the experimental conditions (k ≈ 1 × 10 - 6 to 8 × 10 - 6 mmol/ cm 2 / s ). These results are adjusted according to the specific roughness and texture of each sample, for the results to be more representative of in situ conditions. Batch experiments are also performed to evaluate the extremely low dissolution rates when the solution is close to equilibrium. The results reveal a double kinetics: far from equilibrium, the dissolution rates show that the linear behavior and the kinetic parameters are relatively close with the values found using the rotating disk method. For concentrations greater than 0.94 ± 0.02 of the equilibrium concentration C ref , the dissolution rates show a linear behavior but with greater slope depending on the texture of the mineral. No changes of the dissolution rates were observed on pure gypsum crystals when non soluble solid impurities are added. However, a small degree of uncertainty around the value of C ref show a significant effect on the parameters of the second kinetics. [ABSTRACT FROM AUTHOR]

Water bodies in densely populated lowland areas are commonly affected by pollution from agricultural activities and wastewater treatment plant (WWTP) discharges, yet the selection of appropriate water quality assessment methods for these water bodies is under debate. Therefore, we aimed to 1) compare the ability of structural and functional metrics to detect adverse effects of anthropogenic stress on aquatic ecosystems and 2) assess the ability of trait-based metrics to diagnose the potential causes of the observed adverse effects in water quality assessment. Specifically, we compared the responses of several structural (both taxonomic and trait-based) and functional (i.e., based on ecological processes) metrics across a series of stressors in 20 lowland water bodies affected to varying degrees by agricultural activities and WWTP discharges. The measured stressors included nutrients, dissolved oxygen saturation, water temperature, and proxies for pesticides, pharmaceuticals, and personal care products. Taxa evenness and the trait-based SPEcies At Risk organic (SPEARorganic) and pesticide (SPEARpesticide) metrics were negatively correlated with the proxy for organic toxicants. Microbial decomposition and invertebrate consumption showed opposite and more complex relationships with the stressors. These findings suggest that functional metrics may detect patterns of anthropogenic stress that are not evident from structural metrics alone. In terms of diagnostic value, our results indicated that both SPEAR metrics may be used to diagnose the combined presence of organic toxicants from agricultural activities and WWTP discharges, although the SPEAR approach may need to be combined with other methods. We conclude that structural (both taxonomic and trait-based) and functional metrics may provide complementary information that, when integrated, allows for more thorough water quality assessment strategies. [ABSTRACT FROM AUTHOR]

The use of microfluidics on synchrotron X-ray beamlines represents an advanced sample preparation and delivery platform for state-of-the-art X-ray characterization of micro-samples. The recent developments of 3D printing technologies have opened possibilities for rapid fabrication of complex microfluidic devices. One of the major challenges in 3D printing of microfluidic devices using a digital light processing (DLP) desktop printer is that the static liquid resin trapped in the channels, once the "ceiling" is printed, still receives small doses of light through the subsequently printed layers. This easily triggers partial polymerisation of the resin which impedes its flushing out of the channels after completion of the printing session. We show here that it is possible to gain better control over the resin polymerisation and improve the quality of the microfluidic devices by efficiently reducing the penetration depth of the UV LED light through wavelength selection combined with a careful choice of absorber and photo-initiator materials. We produced and tested several structures using a slightly modified desktop printer at 385 nm wavelength with 37 × 37 μm2 pixel resolution at a printed layer thickness of 25 μm. The structures include particle filters, mixers, droplet generators and droplet storage traps with features below 100 μm. We demonstrate crystallisation of model inorganic and organic compounds in trapped droplets and assess the feasibility of in-device X-ray diffraction experiments. This research opens the path for the use of 3D printed microfluidic devices on X-ray beamlines. [ABSTRACT FROM AUTHOR]

Here we report a synthesis approach that is simple, surfactant free, and green, and which is additionally cost effective in terms of its material requirements. The approach entails the use of an inkjet microreactor for the deposition of silver nanoparticles on the surface of office paper decorated with chitosan nano‐wrinkles for the preparation of a reproducible and sensitive paper‐based surface‐enhanced Raman scattering (SERS) substrate. Silver nanoparticles were synthesized directly in the head nozzles of the inkjet printer via the reduction of silver nitrate (AgNO3) by ascorbic acid. Pre‐modification of the paper with chitosan allowed the formation of randomly oriented nano‐wrinkles on the surface, thus enabling the formation of silver nanoparticles with good hotspots. The novel paper‐based SERS substrate showed outstanding sensitivity and spot‐to‐spot reproducibility for on‐site detection using a portable Raman spectrometer with a limit of detection (LOD) of 10.7 pM. Moreover, our paper‐based SERS substrate has an excellent enhancement factor (EF) of 7.4 × 108, which is difficult to achieve on a paper substrate because of the microporous nature of paper. Finally, the batch‐to‐batch reproducibility and long‐term stability of the SERS substrate under ambient conditions make this substrate a good candidate for point‐of‐care test applications. [ABSTRACT FROM AUTHOR]

Crystallization engineering aims to design and develop solutions for the optimum conversion of natural resources for use by humans, by using crystallization. Crystallization is a cross-scale process, from atoms, ions and molecules in microscale to bulk crystals in macroscale. Fabricating nanomaterials with desired performances is an open issue with multiscale challenges during crystallization. For innovation in crystallization engineering, geology may provide various sources of inspiration such as structures, compositions and formation conditions, if mineral materials can be regarded as novel artificial materials. This review shows us some geo-inspirations that enable people to create and engineer novel materials with satisfactory performance. [ABSTRACT FROM AUTHOR]

We report a simple methodology for the preparation of an efficient visible-light responsive TiO2 photocatalyst through acid treatment of a lepidocrocite-type layered nickel cesium titanate (Cs0.7Ti1.65Ni0.35O4) for interlayer protonation and subsequent calcination at different temperatures (400–600°C) to induce structural transformation. The Ni-doped anatase/rutile nanocomposite possessing a morphology similar to that of protonated layered nickel titanate is obtained at all calcination temperatures. The sample obtained at 600°C exhibits the highest visible-light responsive photocatalytic activity for decomposition of the aqueous methylene blue dye under visible-light (λ > 420 nm) irradiation. The activity is 14 times higher than that of P25 (standard TiO2 photocatalyst) modified with Ni2+ and 3 times higher than that of NiTiO3 (visible-light responsive photocatalyst). The efficient visible-light responsive photocatalytic activity is ascribable to the visible-light absorption ability of the TiO2 phase owing to Ni-doping. Also, an efficient electron transfer across anatase–rutile interfaces for inhibition of charge recombination could be responsible for the activity. This methodology is a new route for efficient visible-light responsive photocatalysts based on TiO2 doped with various elemental species. This is because lepidocrocite-type layered titanates are available in a variety of chemical compositions. [ABSTRACT FROM AUTHOR]

This cross-sectional study aimed to study animal, farm, and within-farm seroprevalence of C. burnetii and to identify associated risk factors in goat and sheep farm in northern Jordan. Questionnaire was developed to collect information about risk factors and farms management practices. Blood samples from 730, ≥ 1-year-old females (goat n = 250; sheep n = 480) were randomly collected from 20 goat herds and 40 sheep flocks. IDEXX ELISA Kit was used to detect C. burnetii antibodies. The overall goat and sheep seroprevalence level was 32.5% (237/730) and was significantly higher in goats (43.3%, 108/250; 95% CI 37–49.6) than sheep (27%, 129/480; 95% CI 29.1–36.2) (χ2 test, p ≤ 0.001). Eighty percent (16/20) of goat herds and 60% (24/40) of sheep flocks had at least one seropositive animal (p ≥ 0.05). The average within goat herds and sheep flock seroprevalence were 36.4% (ranged: 0–91%) and 23.4% (ranged: 0–82%), respectively. Multivariate logistic regression model revealed that seroprevalence increased 1.79 times in goat herds compared with sheep flocks, 3.2 times more in farms containing ≥ 100 animals, and 1.7 times higher in farms with their animals that were ≥ 2 years of age than in farms with their animals that are < 2 years of age. In addition, seroprevalence significantly increased 1.52 times in farms loaning bucks or rams during breeding season and 1.63 times in farms containing cats on premises (p ≤ 0.05). Farm biosecurity measures are essential to prevent introduction and minimize transmission of C. burnetii infection to humans and animals. [ABSTRACT FROM AUTHOR]

Methods obtaining gypsum whiskers via calcining dihydrate or hemihydrate gypsum perform high energy consumption. It also performs potential environmental impacts. New methods with energy-saving, high-efficiency, and environmentally friendly perform great challenges, which aim at fabricating gypsum whiskers even nanowhiskers. In this study, we used high-concentration calcium acetate solution and dilute sulfuric acid to fabricate anhydrite calcium sulfate nanowhiskers with microemulsion solution at room temperature. For further research on regulation and modification of its surface, calcium sulfates were modified by silicone quaternary ammonium salt and fatty acid methyl ester sulfonate in order to study their surface structure and crystal evolution during modification. After characterization, it indicated that the phase of calcium sulfate transmitted from anhydrite phase into dihydrite phase with a slight change on the surface layers. Benefiting from stability and activity properties of calcium sulfate nanowhiskers after modified, the compressive strength of cement paste with only 1% calcium sulfates performed increased absolutely 10.1% and 4.3% at conservation age of 3 days and 28 days. [ABSTRACT FROM AUTHOR]

By virtue of the well‐developed micro‐ and nanofabrication technologies and rapidly progressing surface functionalization strategies, silicon‐based devices have been widely recognized as a highly promising platform for the next‐generation lab‐on‐a‐chip bioanalytical systems with a great potential for point‐of‐care medical diagnostics. Herein, an overview of the latest advances in silicon‐based integrated optofluidic label‐free biosensing technologies relying on the efficient interactions between the evanescent light field at the functionalized surface and specifically bound analytes is presented. State‐of‐the‐art technologies demonstrating label‐free evanescent wave‐based biomarker detection mainly encompass three device configurations, including on‐chip waveguide‐based interferometers, microring resonators, and photonic‐crystal‐based cavities. Moreover, up‐to‐date strategies for elevating the sensitivities and also simplifying the sensing processes are discussed. Emerging laboratory prototypes with advanced integration and packaging schemes incorporating automatic microfluidic components or on‐chip optoelectronic devices lead to one significant step forward in real applications of decentralized diagnostics. Besides, particular attention is paid to currently commercialized label‐free optical bioanalytical models on the market. Finally, the prospects are elaborated with several research routes toward chip‐scale, low‐cost, highly sensitive, multi‐functional, and user‐friendly bioanalytical systems benefiting to global healthcare. [ABSTRACT FROM AUTHOR]

Development of reliable, sensitive, selective, and miniaturized sensing technologies is critical for health assessment and early diagnosis and treatment of diseases/anomalies while simultaneously mitigating the challenges associated with in vivo measurements. Some critical constraints to the realization of in vivo measurements include the necessity to fabricate the sensor on a tightly constrained footprint while ensuring acceptable biocompatibility, accuracy, and reliability. The inherent light‐guiding properties of optical fibers over long distances, their microscopic cross‐section that can be structured at the nanoscale to manipulate the light transmittance/reflectance spectrum, excellent biocompatibility enabling their efficient integration with biorecognition molecules, immunity to electromagnetic interference, mechanical flexibility, and low cost have been inviting research attention to utilize these unique features for in vivo and label‐free point‐of‐care diagnostics. Hence, fiber‐optic biosensing has become a promising research thrust, with a plethora of emerging methodologies to develop ultrasensitive and selective sensing probes. A unified presentation of the research trends on biosensors incorporated into optical fibers is presented. [ABSTRACT FROM AUTHOR]

FDCA esters are highly relevant biobased alternatives for currently used benzene dicarboxylic acid esters. Despite all the developments on 2,5-FDCA applications, to the best of our knowledge thus far no toxicological data were available for 2,5-FDCA esters. In the present study we aimed to fill this gap, by using an in vitro reporter gene assay approach to compare the activity profile of commonly used phthalates to that of their furan-based counterparts. The assay selection was aimed at the detection of endocrine activity, since several phthalates are heavily scrutinised for their endocrine disrupting properties. However, to avoid missing other relevant toxicological endpoints, several assays able to detect various forms of cellular stress were also included in the panel. The results showed that the (ortho)benzene dicarboxylic acid esters were predominantly active on several of the endocrine assays. In comparison, six of the seven furan dicarboxylic acid based diesters tested here showed no activity in any of the 13 assays used. Only the isobutyl derivative DIBF showed moderate estrogenic activity on one assay, compared to much more pronounced activities on four assays for the ortho-phthalate analogue. Overall, the results presented in this paper are a strong indication that 2,5-FDCA based diesters in general are not only technically viable alternatives to phthalates, but also offer significant toxicological benefits, which supports a non-regrettable substitution. [ABSTRACT FROM AUTHOR]

Optical manipulation, separation, and detection of biological cells have immense potential biomedical applications, for example, in disease detection. In this paper, we present optical manipulation and detection of micron sized fluorescent particles inside hollow-core photonic crystal fiber (HC-PCF) by transverse optical trapping. An optical trapping system is designed where a near-infrared laser light is focused using a microscope objective to create an optical trap across a liquid-filled HC-PCF. The fluorescent microsphere particles trapped in the core of HC-PCF using the laser induced optical force further undergo imaging and fluorescence spectroscopic analysis. It is illustrated that the proposed method can track the particle into a different medium using the optical trap as well. The obtained results indicate that this proposed method has tangible potential for developing HC-PCF based lab-on-a-chip bio/chemical sensors capable of detecting reagents in ultra low sample volumes. [ABSTRACT FROM AUTHOR]

Films of titanate nanosheets (approx. 1.8-nm layer thickness and 200-nm size) having a lamellar structure can form electrolyte-filled semi-permeable channels containing tetrabutylammonium cations. By evaporation of a colloidal solution, persistent deposits are readily formed with approx. 10-μm thickness on a 6-μm-thick poly(ethylene-terephthalate) (PET) substrate with a 20-μm diameter microhole. When immersed in aqueous solution, the titanate nanosheets exhibit a p.z.c. of − 37 mV, consistent with the formation of a cation conducting (semi-permeable) deposit. With a sufficiently low ionic strength in the aqueous electrolyte, ionic current rectification is observed (cationic diode behaviour). Currents can be dissected into (i) electrolyte cation transport, (ii) electrolyte anion transport and (iii) water heterolysis causing additional proton transport. For all types of electrolyte cations, a water heterolysis mechanism is observed. For Ca2+ and Mg2+ions, water heterolysis causes ion current blocking, presumably due to localised hydroxide-induced precipitation processes. Aqueous NBu4+ is shown to 'invert' the diode effect (from cationic to anionic diode). Potential for applications in desalination and/or ion sensing are discussed. [ABSTRACT FROM AUTHOR]

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SiO2 and Pd/SiO2 nanocomposites were prepared using sol-gel method and characterized by X-ray diffraction, Fourier transform infrared spectra, scanning electron microscopy and different heating rate thermogravimetric-differential thermogravimetric analysis. The apparent activation energies (Ea) were calculated using the Kissinger's and Ozawa's methods. The most probable kinetic mechanism functions were obtained by master plot method. The entropy (ΔS≠), enthalpy (ΔH≠) and activation free energy (ΔG≠) were calculated using three methods. The results demonstrated that the thermal decomposition processes of both materials are the three-step reactions. After thermal condition in air atmosphere, the introduced hydrophobic Si-CH3 group in Pd/SiO2 gel materials was completely decomposed into inorganic composition, and the Pd element was transformed into PdO and metallic Pd. The Ea values obtained by Kissinger's method are close to those by Ozawa's method. The Pd-doping can increase the thermal decomposition activation energies and improve the thermal stability of SiO2 material. The decomposition mechanisms for the three stages are the assumed random nucleation and its subsequent growth, irrespective of the Pd-doping. Compared with SiO2 material, the thermal decomposition of Pd/SiO2 requires more energy due to the increasing ΔH≠. The ΔH≠ values calculated by method II are nearly equal to the Ea values from the Kissinger's and Ozawa's methods, which indicated that the thermodynamic parameters obtained by method II are the most accurate. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, we demonstrate the use of a disposable luciferase‐based microfluidic bioassay chip for environmental monitoring and methods for fabrication. The designed microfluidic system includes a chamber with immobilized enzymes of bioluminescent bacteria Photobacterium leiognathi and Vibrio fischeri and their substrates, which dissolve after the introduction of the water sample and thus activate bioluminescent reactions. Limits of detection for copper (II) sulfate, 1,3‐dihydroxybenzene and 1,4‐benzoquinone for the proposed microfluidic biosensor measured 3 μM, 15 mM, and 2 μM respectively, and these values are higher or close to the level of conventional environmental biosensors based on lyophilized bacteria. Approaches for entrapment of enzymes on poly(methyl methacrylate) (PMMA) plates using a gelatin scaffold and solvent bonding of PMMA chip plates under room temperature were suggested. The proposed microfluidic system may be used with some available luminometers and future portable luminescence readers. [ABSTRACT FROM AUTHOR]

This tutorial aims to provide a general overview on the state-of-the-art of photonic integrated circuits (PICs) in the visible and short near-infrared (NIR) wavelength ranges, mostly focusing in silicon nitride (SiN) substrates, and a guide to the necessary steps in the design toward the fabrication of such PICs. The focus is put on bio- and life sciences, given the adequacy and, thus, a large number of applications in this field. [ABSTRACT FROM AUTHOR]

Coxiella burnetii is an intracellular pathogen that causes human Q fever, a disease that normally presents as a severe flu-like illness. Due to high infectivity and disease severity, the pathogen is considered a risk group 3 organism. Full-length lipopolysaccharide (LPS) is required for full virulence and disease by C. burnetii and is the only virulence factor currently defined by infection of an immunocompetent animal. Transition of virulent phase I bacteria with smooth LPS, to avirulent phase II bacteria with rough LPS, occurs during in vitro passage. Semi-rough intermediate forms are also observed. Here, the genetic basis of LPS phase conversion was investigated to obtain a more complete understanding of C. burnetii pathogenesis. Whole genome sequencing of strains producing intermediate and/or phase II LPS identified several common mutations in predicted LPS biosynthesis genes. After passage in broth culture for 30 weeks, phase I strains from different genomic groups exhibited similar phase transition kinetics and elevation of mutations in LPS biosynthesis genes. Targeted mutagenesis and genetic complementation using a new C. burnetii nutritional selection system based on lysine auxotrophy confirmed that six of the mutated genes were necessary for production of phase I LPS. Disruption of two of these genes in a C. burnetii phase I strain resulted in production of phase II LPS, suggesting inhibition of the encoded enzymes could represent a new therapeutic strategy for treatment of Q fever. Additionally, targeted mutagenesis of genes encoding LPS biosynthesis enzymes can now be used to construct new phase II strains from different genomic groups for use in pathogen-host studies at risk group 2 level. [ABSTRACT FROM AUTHOR]

With the energy crisis and resource depletion nowadays, novel, highly performing, and cost-effective semiconductors are in urgent demand for efficiently harvesting solar energy for photoelectrochemical applications. Herein, this study presents low-cost anatase TiO hollow nanoparticles as prepared by a critical liquid-phase deposition (LPD) processing combined with a hydrothermal reaction and calcination processing, without involving any templates. The additional LPD processing not only makes the resulting samples more visible light responsive, but also results in hollowing the TiO nanoparticles (nanosheets vs. hollow nanoparticles). Importantly, commercial TiO powder is employed as the starting material to achieve the final synthesis of TiO hollow nanoparticles, making it scalable and cost-effective for production and applications. As a by-product, the fluoride, formed during the preparation process, is assumed to play a significant role in hollowing through chemically induced self-transformation and Ostwald ripening, in addition to enhancing the crystallinity. The beneficial structural evolution to the hollow nanoparticles enables the improvement of the photoelectrochemical performance through impressive inhibition of the recombination of the photoelectrons and holes, which is well evidenced by I and EIS (Nyquist plot), as well as by I- V curve and electron lifetime evaluations as for the assembled DSSCs with the prepared TiO hollow nanoparticles under simulated sunlight illumination (50 mW/cm). [ABSTRACT FROM AUTHOR]

A simple and cost-effective method for the synthesis of a porous Al scaffold has been optimised using only NaAlH and TiCl. The starting materials were compacted into a pellet and sintered under dynamic vacuum to remove the Na and H. The sintering conditions, such as vacuum level, temperature, and time, were the key factors that influenced both the extraction of Na and H from the pellet and the overall porosity. Quantitative phase analysis by X-ray diffraction revealed that after the sintering process, the as-prepared porous Al scaffold consisted primarily of Al. Morphological observations conducted by scanning electron microscopy showed that the scaffold exhibited an open network of pores with a small number of mesopores and no formation of micropores. The specific surface area of the scaffold was determined to be 7.9 ± 0.1 and 6.0 ± 0.5 m/g by the Brunauer-Emmet-Teller method and from small-angle X-ray scattering measurements, respectively. The total porosity of the Al scaffold was 44.6%. [ABSTRACT FROM AUTHOR]

During the last couple of decades, the rapidly advancing field of nanotechnology has produced a wide palette of nanomaterials, most of which are considered as “synthetic” and, among the wider public, are often met with a certain suspicion. Despite the technological sophistication behind many of these materials, “nano” does not always equate with “artificial”. Indeed, nature itself is an excellent nanotechnologist. It provides us with a range of fine particles, from inorganic ash, soot, sulfur and mineral particles found in the air or in wells, to sulfur and selenium nanoparticles produced by many bacteria and yeasts. These nanomaterials are entirely natural, and, not surprisingly, there is a growing interest in the development of natural nanoproducts, for instance in the emerging fields of phyto- and phyco-nanotechnology. This review will highlight some of the most recent—and sometimes unexpected—advances in this exciting and diverse field of research and development. Naturally occurring nanomaterials, artificially produced nanomaterials of natural products as well as naturally occurring or produced nanomaterials of natural products all show their own, particular chemical and physical properties, biological activities and promise for applications, especially in the fields of medicine, nutrition, cosmetics and agriculture. In the future, such natural nanoparticles will not only stimulate research and add a greener outlook to a traditionally high-tech field, they will also provide solutions—pardon—suspensions for a range of problems. Here, we may anticipate specific biogenic factories, valuable new materials based on waste, the effective removal of contaminants as part of nano-bioremediation, and the conversion of poorly soluble substances and materials to biologically available forms for practical uses. [ABSTRACT FROM AUTHOR]

Synchrotron-based small-and wide-angle X-ray scattering (SAXS/WAXS) was used to examine in situ the precipitation of gypsum (CaSO4·2H2O) from solution. We determined the role of (I) supersaturation, (II) temperature and (III) additives (Mg2+ and citric acid) on the precipitation mechanism and rate of gypsum. Detailed analysis of the SAXS data showed that for all tested supersaturations and temperatures the same nucleation pathway was maintained, i.e., formation of primary particles that aggregate and transform/re-organize into gypsum. In the presence of Mg2+ more primary particle are formed compared to the pure experiment, but the onset of their transformation/reorganization was slowed down. Citrate reduces the formation of primary particles resulting in a longer induction time of gypsum formation. Based on theWAXS data we determined that the precipitation rate of gypsum increased 5-fold from 4 to 40 °C, which results in an effective activation energy of ∼30 kJ·mol-1. Mg2+ reduces the precipitation rate of gypsum by more than half, most likely by blocking the attachment sites of the growth units, while citric acid only weakly hampers the growth of gypsum by lowering the effective supersaturation. In short, our results show that the nucleation mechanism is independent of the solution conditions and that Mg2+ and citric acid influence differently the nucleation pathway and growth kinetics of gypsum. These insights are key for further improving our ability to control the crystallization process of calcium sulphate. [ABSTRACT FROM AUTHOR]

Any poorly crystalline serpentine-type mineral with a lack of recognizable textural or diffraction features for typical serpentine varieties (i.e., chryotile, lizardite, and antigorite) is usually referred to as proto-serpentine. The formation of the so-called proto-serpentine seems ubiquitous in serpentinization reactions. It is related to dissolution-precipitation of strongly reactive particles prior to true serpentine formation (e.g., in veins where both chrysotile and proto-serpentine are described). However, the structural characteristics of proto-serpentine and its relation with serpentine crystalline varieties remain unclear. In this study a model describing the transformation from proto-serpentine to chrysotile is presented based on experimental chrysotile synthesis using thermogravimetric analyses, transmission electron microscopy, and high-energy X-ray diffraction with pair distribution function analyses. The combination of the high-resolution TEM and high-energy X-ray diffraction enables to resolve the local order of neo-formed particles and their structuration processes occurring during pure chrysotile formation (i.e., during the first three hours of reaction). The formation of individual nanotubes is preceded by the formation of small nanocrystals that already show a chrysotile short-range order, forming porous anastomosing features of hydrophilic crystallites mixed with brucite. This is followed by a hierarchical aggregation of particles into a fiber-like structure. These flake-like particles subsequently stack forming concentric layers with the chrysotile structure. Finally, the individualization of chrysotile nanotubes with a homogeneous distribution of diameter and lengths (several hundreds of nanometer in length) is observed. The competitive precipitation of brucite and transient serpentine during incipient serpentinization reaction indicates that both dissolution-precipitation and serpentine-particle aggregation processes operate to form individual chrysotile. This study sheds light into mineralization processes and sets a first milestone toward the identification of the factors controlling polymorph selection mechanisms in this fascinating system. [ABSTRACT FROM AUTHOR]

Coxiella burnetii is an intracellular bacterial pathogen that causes human Q fever, an acute flu-like illness that can progress to chronic endocarditis and liver and bone infections. Humans are typically infected by aerosol-mediated transmission, and C. burnetii initially targets alveolar macrophages wherein the pathogen replicates in a phagolysosome-like niche known as the parasitophorous vacuole (PV). C. burnetii manipulates host cAMP-dependent protein kinase (PKA) signaling to promote PV formation, cell survival, and bacterial replication. In this study, we identified the actin regulatory protein vasodilator-stimulated phosphoprotein (VASP) as a PKA substrate that is increasingly phosphorylated at S157 and S239 during C. burnetii infection. Avirulent and virulent C. burnetii triggered increased levels of phosphorylated VASP in macrophage-like THP-1 cells and primary human alveolar macrophages, and this event required the Cα subunit of PKA. VASP phosphorylation also required bacterial protein synthesis and secretion of effector proteins via a type IV secretion system, indicating the pathogen actively triggers prolonged VASP phosphorylation. Optimal PV formation and intracellular bacterial replication required VASP activity, as siRNA-mediated depletion of VASP reduced PV size and bacterial growth. Interestingly, ectopic expression of a phospho-mimetic VASP (S239E) mutant protein prevented optimal PV formation, whereas VASP (S157E) mutant expression had no effect. VASP (S239E) expression also prevented trafficking of bead-containing phagosomes to the PV, indicating proper VASP activity is critical for heterotypic fusion events that control PV expansion in macrophages. Finally, expression of dominant negative VASP (S157A) in C. burnetii-infected cells impaired PV formation, confirming importance of the protein for proper infection. This study provides the first evidence of VASP manipulation by an intravacuolar bacterial pathogen via activation of PKA in human macrophages. [ABSTRACT FROM AUTHOR]

Abstract: Metal–organic frameworks are appealing hybrid solids which attract continuously growing interest. Their advantageous application in sensing devices is demonstrated here. In particular, the use of a short‐pulse laser excitation of luminescent metal‐organic framework is reported for the first time to favor the ligand‐based emission. The designed MOF‐based system achieves in vitro H2S dosing by turn‐on fluorescence with unprecedented sensitivity. The Al‐MIL‐101‐based sensor detects sulfide produced by living cells and sulfide‐releasing molecules in physiological media with a constant accuracy at sub‐micromolar levels. The reported sensitivity is suitable for medical applications and opens new perspectives in the design of new point‐of‐care testing devices. The detailed relationship between photoluminescence mechanisms and chemical modification of the MOF upon sensing is also reported. [ABSTRACT FROM AUTHOR]

Supported microporous organosilica membranes made from bridged silsesquioxane precursors by an acid-catalyzed sol-gel process have demonstrated a remarkable hydrothermal stability in pervaporation and gas separation processes, making them the first generation of ceramic molecular sieving membranes with sufficient performance under industrially relevant conditions. The commercial availability of various α,ω-bis(trialkoxysilyl)alkane and 1,4-bis(trialkoxysilyl)benzene precursors facilitates the tailoring of membrane properties like pore size and surface chemistry via the choice of precursor(s) and process variables. Here, we describe the engineering of sols for making supported microporous thin films, discuss the thermal and hydrothermal stability of microporous organosilicas and give a short overview of the developments and applications of these membranes in liquid and gas separation processes since their first report in 2008. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Exfoliation of layered inorganic nanomaterials into single-layered sheets has been widely interested in materials chemistry and composite fabrication. Here, we report the exfoliation of layered zirconium phosphate nanoplatelets by using small molecule intercalating agents in ionic liquids, which opens a new platform for fabricating singlelayered inorganic materials from synthetic layered compounds. [ABSTRACT FROM AUTHOR]

A Pd-doped organosilica membrane based on bis(triethoxysilyl)ethane is successfully developed by the polymeric sol-gel method. Its microstructure, chemical composition, and separation performance are compared with those of the undoped organosilica membrane. Gas adsorption analysis indicates that the Pd-doped organosilica membrane has larger micropores compared with the undoped organosilica membrane. The gas permeation results show that the Pd-doped organosilica membrane has much higher gas permeances than the undoped organosilica membrane due to the enlarged micropores after Pd-doping. The Pd-doped organosilica membrane also exhibits a significantly improved hydrothermal stability. The enhanced hydrothermal stability can be explained by the mechanism that Pd particles act as inhibitors and prevent the formation of mobile silica groups (e.g., Si-OH) under steam condition. Metal-doping (e.g., Pd-doping in this work) may offer a new approach to develop high performance membranes with enhanced gas permeances and hydrothermal stabilities in gas separation applications. [ABSTRACT FROM AUTHOR]

Background: Long-term fatigue with detrimental effects on daily functioning often occurs following acute Q-fever. Following the 2007–2010 Q-fever outbreak in the Netherlands with over 4000 notified cases, the emphasis on long-term consequences of Q-fever increased. The aim of this study was to provide an overview of all relevant available literature, and to identify knowledge gaps regarding the definition, diagnosis, background, description, aetiology, prevention, therapy, and prognosis, of fatigue following acute Q-fever. Design: A systematic review was conducted through searching Pubmed, Embase, and PsycInfo for relevant literature up to 26th May 2015. References of included articles were hand searched for additional documents, and included articles were quality assessed. Results: Fifty-seven articles were included and four documents classified as grey literature. The quality of most studies was low. The studies suggest that although most patients recover from fatigue within 6–12 months after acute Q-fever, approximately 20% remain chronically fatigued. Several names are used indicating fatigue following acute Q-fever, of which Q-fever fatigue syndrome (QFS) is most customary. Although QFS is described to occur frequently in many countries, a uniform definition is lacking. The studies report major health and work-related consequences, and is frequently accompanied by nonspecific complaints. There is no consensus with regard to aetiology, prevention, treatment, and prognosis. Conclusions: Long-term fatigue following acute Q-fever, generally referred to as QFS, has major health-related consequences. However, information on aetiology, prevention, treatment, and prognosis of QFS is underrepresented in the international literature. In order to facilitate comparison of findings, and as platform for future studies, a uniform definition and diagnostic work-up and uniform measurement tools for QFS are proposed. [ABSTRACT FROM AUTHOR]