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In this paper, the effects of hygrothermal conditions on various behaviors, such as bending, free vibration, mechanical and thermal buckling, of exponentially graded microplates lying on two-parameter elastic foundations are investigated. The trigonometric four-variable plate theory incorporated to the modified couple stress theory (MCST) is employed to derive the equations of motion. The present MCST contains an internal material length scale parameter, thus it can capture the size effect. The microplate is assumed to be subjected to a temperature rise and moisture concentration which are varied linearly through the thickness of the plate. Based on an exponential law, the material properties of the microplate are graded only in z direction. The equations of motion are solved analytically to obtain the displacements, stresses, eigenfrequencies and critical buckling load and temperature of the microplates. The present results are validated by comparing them with those previously published. The numerical examples reveal that considering the size effect and/or the elastic foundations leads to an increment in plate stiffness and thereby leads to a decrement in the deflection and an increment in eigenfrequency and buckling loads. It is also shown that the size effect is negligible for the thicker plate. [ABSTRACT FROM AUTHOR]

The Microplate-based method is a useful means for high-throughput screening and kinetic studies of microalgal growth. In this study, the statistical evaluation of growth and carbohydrate production by a marine microalga, designated as Picochlorum sp. D8, which is taxonomically affiliated to Picochlorum sp. SENEW3 was done on a miniaturized scale. Initially, the significance of various factors was studied by using the Plackett–Burman Design. The Central Composite Design was applied to compute the optimum level of significant factors, e.g., phosphate (KH 2 PO 4 +K 2 HPO 4) and FeCl 3 ·6H 2 O. Maximum carbohydrate production was obtained at low phosphate (0.148 g/L) and FeCl 3 ·6H 2 O (0.009 g/L) concentrations. The validation experiments were carried out under optimal conditions, where carbohydrate content increased by 3.5 times. The analyses of the results showed a quadratic effect of phosphate and FeCl 3 ·6H 2 O concentrations. • Introducing a new microalga for the production of carbohydrate and bioethanol. • Describing the microplate-based method as an effective platform for optimization. • Phosphate and FeCl 3 ·6H 2 O significantly affect carbohydrate production. • Under optimized condition, the carbohydrate content was increased by 3.5 folds. [ABSTRACT FROM AUTHOR]

This paper deals with the small-scale effects on the thermoelastic damping (TED) in microplates. The coupled equations of motion and heat conduction are provided utilizing the strain gradient theory (SGT) and the dual-phase-lag (DPL) heat conduction model. Solving these equations and adopting the Galerkin method, the real and imaginary parts of frequency are extracted. The complex frequency approach is then employed to present a size-dependent expression for evaluating TED in thin plates. An analytical expression for TED incorporating small-scale effects is also derived on the basis of the energy dissipation approach. To survey the effect of different continuum theories on TED, the results obtained by SGT are compared with those predicted by the modified couple stress theory (MCST) and the classical continuum theory. Furthermore, through a number of parametric studies, the effects of some variables on the amount of TED, such as microplate thickness, type of material and boundary conditions are discussed. [ABSTRACT FROM AUTHOR]

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A microplate-based sandwich assay for the determination of α-human thrombin (HTb) was developed. Fluorescein-modified 29-mer thrombin binding aptamer (FAM-TBA29) and biotinylated 15-mer thrombin binding aptamer (Bio-TBA15) reacting with different exosites of HTb were used as the biorecognition components in the assay. FAM-TBA29 (capture aptamer) was immobilized using its interaction with anti-fluorescein antibody adsorbed on the microplate surface. As a sensitive signaling system, a combination of Bio-TBA15 and streptavidin-polyHRP conjugate was used. Under the optimized conditions, the detection limit for HTb was 1.4 nM; this value was the same in both the colorimetric and the chemiluminescent assays. The replacement of colorimetry for HRP measurement with chemiluminescence increased the assay sensitivity from 0.06 to 1.7 × 106 nM−1 that clearly demonstrated advantage of the latter approach. [ABSTRACT FROM AUTHOR]

Effects of the type of microplates and solvent for preparation of caspofungin (CPFG) on antifungal susceptibility testing of CPFG against clinical isolates of Candida albicans, Candida glabrata, and Candida krusei (20strains each) by broth microdilution method according to the Clinical and Laboratory Standards Institute were evaluated. When CPFG was dissolved in water, MICs against the three Candida species decreased 3. 1-6. 0-fold in surface-untreated microplates compared to those in treated microplates. When CPFG was dissolved in dimethyl sulfoxide, MICs against the three Candida species decreased 1.3-2.5-fold in surface-untreated microplates compared to those in treated microplates. Differences in MICs according to the type of solvent did not exceed the difference for one dilution interval (0.5-2-fold MIC ratio) regardless of whether the microplate surface was treated or not. These findings suggest that differences in CPFG MICs may depend mainly on the type of surface treatment of assay microplates. [ABSTRACT FROM AUTHOR]

Introduction: Increased facial trauma has led to advances in techniques of internal fixation, improvements in plating system, refinements in exposure of facial skeleton fueling the rapid use of internal fixation for the management of facial fractures. Evaluating 40 patients with confirmed midfacial (Le Fort I and II) and mandibular fractures, this study presents the efficacy of microplate in comparison with miniplate in terms of load bearing capacity, stability at the fracture site and postoperative palpability. Objectives: To evaluate the efficacy of microplates in comparison with miniplates in maxillofacial trauma. Materials and Methods: Study sample consists 40 subjects, 20 each in two groups clinically and radiographically diagnosed with Group 1 (maxillary) and Group 2 (mandibular fractures) which were subdivided into 10 each treated with miniplate and microplate respectively. Postoperatively, stability of fracture, bite force, need for postop MMF, pain, infection, wound dehiscence, mouth opening, occlusion and palpability was noted. All cases have been evaluated clinically for various parameters for minimum of 3 months to assess any postoperative complications. Results: We found microplates are stable enough and have adequate load bearing capacity. Due to close adaptability and less hardware, postoperative palpability is less but larger sample study with long term follow up is necessary to conclude its efficacy in load bearing fracture sites. [ABSTRACT FROM AUTHOR]

Abstract Background Improved methods with better separation and concentration ability for detection of foodborne pathogens are in constant need. The aim of this study was to evaluate microplate immunocapture (IC) method for detection of Salmonella Typhi, Shigella flexneri and Vibrio cholerae from food samples to provide a better alternative to conventional culture based methods. Results The IC method was optimized for incubation time, bacterial concentration, and capture efficiency. 6 h incubation and log 6 CFU/ml cell concentration provided optimal results. The method was shown to be highly specific for the pathogens concerned. Capture efficiency (CE) was around 100% of the target pathogens, whereas CE was either zero or very low for non-target pathogens. The IC method also showed better pathogen detection ability at different concentrations of cells from artificially contaminated food samples in comparison with culture based methods. Performance parameter of the method was also comparable (Detection limit- 25 CFU/25 g; sensitivity 100%; specificity-96.8%; Accuracy-96.7%), even better than culture based methods (Detection limit- 125 CFU/25 g; sensitivity 95.9%; specificity-97%; Accuracy-96.2%). Conclusion The IC method poses to be the potential to be used as a method of choice for detection of foodborne pathogens in routine laboratory practice after proper validation.

This paper proposes the use of microplates as a new flow control device to suppress boundary layer separation on blades and thus improve the aerodynamic performance of a low-speed axial flow fan. A computational study is performed by means of computational fluid dynamics (CFD) simulations. Numerical investigations are carried out based on Reynolds-averaged Navier-Stokes (RANS) method. The shear stress transport (SST) turbulence model and high-quality computational grids are adopted for CFD simulations. An exhaustive comparison of the fans with and without control has been conducted in terms of characteristic curves, streamlines and pressure distributions. The purpose of this work is to better understand the underlying flow control mechanisms of microplates. It is found that the total efficiency is slightly lowered when the controlled fan operates at the design flow rate. However, as the flow rate changes, the total efficiency of the controlled fan varies more gently than the original fan without control. Traced streamlines show that flow separation on blade surfaces is effectively controlled and radial flow migration on the suction surface is evidently diminished. Numerical results indicate that microplates significantly alleviate fan stall and have considerable beneficial effects on fan performance.

Microtiter plates are suitable for screening and process development of most microorganisms. They are currently the container of choice for high-throughput and small-scale microbial culture, but require optimization for specific work. In this research, a novel type of microtiter plate was developed using computational fluid dynamics (CFD) technology. The new plate provided high oxygen supply and optimal mixing effects for the fermentation culture of docosahexaenoic acid (DHA) producing strains, surpassing the conventional method of strain screening with shake flasks, which was insufficient. The shape of the microtiter plate was modified, and baffles were introduced to improve mass transfer and oxygen supply effects in the vibrating bioreactor. CFD technology was used to model the new plate's characteristics, establishing the superiority of hexagonal microtiter plates with six baffles. Parameters in the incubation process, such as vibration frequency and liquid load, were optimized, and the final result achieved an oxygen transfer coefficient (K L a) of 0.61 s -1 and a volume power input of 2364 w m -3 , which was four to five times better than the original 96-well plate. The culture results optimized by the model were also verified. Therefore, this new microtiter plate provides a powerful tool for future high-throughput screening of strains., (© 2023 Wiley-VCH GmbH.)

In the South Atlantic, a reorganization of the Mid‐Atlantic Ridge began before anomaly C34n (83.6 Ma) and ended before anomaly C30n (66.4 Ma), complicating tectonics of Rio Grande Rise and older Walvis Ridge (WR), which formed together at the Mid‐Atlantic Ridge. This reorganization is poorly understood because magnetic anomalies C30n‐C34n are poorly defined near WR. We interpreted these anomalies along western WR to improve knowledge of Rio Grande Rise‐WR tectonic development. Anomaly trends indicate that Valdivia Bank has an E‐W age progression, perpendicular to that predicted by hot spot models. Anomaly spacing and width is irregular and anomalous near WR, implying a series of ridge jumps and possibly a microplate between anomalies C34n and C32n. Eastward ridge jumps transferred microplate lithosphere to the South American plate. This study shows that Late Cretaceous tectonic evolution of the Rio Grande Rise‐WR large igneous provinces was more complex than previously understood. Plain Language Summary: Walvis Ridge and Rio Grande Rise are two large volcanic mountain ranges formed on the African and the South American plates, respectively, as the South Atlantic opened during Cretaceous and Cenozoic times. Between anomalies C34n (83.6 Ma) and anomaly C30n (66.4 Ma), a reorganization of the Mid‐Atlantic Ridge complicated the tectonic development of these two igneous provinces. This process is not well understood due to the sparse distribution of magnetic anomalies C30n‐C34n near Walvis Ridge. Analyzing magnetic anomaly data, we improved the interpretation of magnetic anomalies near Walvis Ridge. The updated magnetic anomaly pattern indicates that Valdivia Bank has an E‐W age progression, rather than the N‐S trend as predicted by hot spot models. Uneven anomaly spacing and width imply complex tectonics, including ridge jumps and possibly the formation of a microplate. Eastward ridge jumps transferred lithosphere from the African plate to South American plate. This study shows that the Late Cretaceous tectonic evolution of the Rio Grande Rise‐Walvis Ridge large igneous provinces was more complex than previously understood. Key Points: We identified Late Cretaceous magnetic anomalies C33n‐C34n along Walvis Ridge where these anomalies were not previously identifiedAnomaly patterns infer that Valdivia Bank has an E‐W trending age progression in contrast with the N‐S age progression implied by the hot spot modelsUneven anomaly width and spacing indicate complex tectonics between Walvis Ridge and Rio Grande Rise between anomalies C34n and C30n [ABSTRACT FROM AUTHOR]

The Central Indian Ocean Basin, east of the southern Chagos Laccadive Ridge complex has evolved due to seafloor spreading in the N-S direction since the Late Cretaceous. The trace of the Rodriguez Triple Junction (RTJ) has been inferred in this basin, but its exact location and dynamics prior to C29o are not known. About 20,000 km of total magnetic intensity data along with satellite gravity mosaic were used to understand the dynamics of the RTJ in the Late Cretaceous. Synthetic seafloor spreading models endorse the presence of Late Cretaceous to early Palaeogene magnetic anomalies C34y to C24o in the study area. Half-spreading rates are initially low (32 mm/yr) between C34y to C33y, and increase up to 78 mm/yr by C28y. Thereafter a decreasing trend is seen (57 mm/yr). Towards the west in the study area, higher spreading rates (120 mm/yr) between C33y and C32ay, and distorted anomalies between chrons C32ay and C30y are observed. Detailed geophysical analysis suggests that the higher spreading rates are due to the presence of transferred crust, and the distorted anomalies are caused by the presence of fragmented tectonic blocks depicting microplate formation and rotation. Plate reconstruction models suggest that the RTJ at C34y time lay southwest of Comorin Ridge which coincided with the northern edge of the Conrad Rise. Until C33y, the RTJ left a linear trace parallel to the fracture zone trend on both the Indian and Antarctic plates, while it gradually moved eastwards on the African plate. The RTJ migrated westwards until C31y causing the transfer of a considerable amount of crust from the African plate to both the Indian and Antarctic plates. Thereafter, the RTJ rapidly reversed its migration direction towards the east until C29o causing the formation and rotation of a microplate on the Indian plate and lengthening of the Southwest Indian Ridge. The present study suggests that this episodic migration of the RTJ may be due to ridge propagation under the influence of the Marion hotspot which was in the vicinity during that period. This RTJ migration resulted in microplate formation, lithospheric transfer and thickened lithosphere similar to the inferences made at many triple junctions in the Pacific Ocean. Thus the origin of anomalous structures such as the Crozet Bank may be related to triple junction dynamics under the influence of Marion hotspot. Further, the counter clockwise rotation of the Southwest Indian Ridge between C33y and C29y may have a causal link with the formation and rotation of the microplate, which occurred during the same period. The present study thus facilitated the inference of the dynamics of the RTJ trace between C34y and C29o on the three plates. • Transferred crust and fossil microplate inferred in the western Central Indian Ocean Basin • Episodic westward/eastward migration of the Rodriguez Triple Junction from C33y-C29o • Formation of anomalous tectonic structures under the influence of Marion hotspot • Southwest Indian Ridge fracture zones rotation linked to triple junction migration [ABSTRACT FROM AUTHOR]

A functionally graded Boltzmann hierarchical viscoelastic model with both stress- and strain-gradient nonlocalities is developed and implemented to extract results that are more precise than results of Eringen's nonlocal elasticity model. The available size-dependent vibration analyses of the nano/microplates have focused on the frequency analysis and even not the time-dependent transient vibration analyses. In the present research, the forced and transient responses of the microplates are studied comprehensively, for the first time, using a three-element standard solid viscoelastic model. The studied transversely symmetric graded viscoelastic microplate and the relevant function of the material properties variations contain notable hints as well. Furthermore, the resulting new sixth-order nonlocal strain gradient integrodifferential equations are solved by a special technique that includes an analytical spatial Navier series-type solution and a trapezoidal and Runge–Kutta integration schemes, in time domain. Finally, the influences of the stress- and strain-gradient nonlocality parameters and the viscoelasticity parameters on the dynamic behaviors of the viscoelastic FGM microplates are investigated in details. Results show that the effects of the strain gradient nonlocality on the viscodynamic results may be much remarkable than those of the length scale nonlocality, in microscales. [ABSTRACT FROM AUTHOR]

Utilization of algae includes both macroalgae for human consumption dating back to thousands of years, as well as the application of microalgae in health promoting dietary supplements. The autotrophic growth of microalgae is slow, but can be accelerated by optimizing their cultivation conditions. Efficiency optimizations for time and economy should be performed in many parallel experiments. A new high-throughput microalgae cultivation method is presented here, applying 24-low-well microplate with varying illumination, in which the cell growth is followed via evaluation of scanned images. A strain of the genus Nannochloropsis and two Chlorella vulgaris species have been chosen as well described and frequently applied model organisms in order to test the recently developed cultivation system. In these scaled down experiments, the custom design lighting panel was tested by studying the effect of the colour of illumination on cell growth kinetics. RGB LEDs (i.e. light emitting diodes, red: 622 nm, green: 528 nm, and blue: 467 nm) were used individually or together providing red, green, blue, and white colours. While the effect of light's colour on algae growth was evaluated, also the new system was proven to be suitable for comparing maximal growth rates for different microalgae strains. While the tested two Chlorella isolates reached 1.2–1.4 g l–1 concentrations, the Nannochloropsis strain reached 1.4 g l–1 final cell dry weight, and specific growth rates were observed between 0.58–0.62 day–1. [ABSTRACT FROM AUTHOR]

Highlights • A model for thermoelastic damping in the trilayered microplates is developed. • The energy dissipation in the middle part is less than that in the outer parts for homogenous microplates. • Damping spectrums are associated with the critical damping frequency and the Zener's modulus of each layer. • The middle layers may exhibit negative thermoelastic damping. Abstract The design of laminated composite microplate resonators with high quality (Q) factors requires careful analysis of thermoelastic damping since it is an inherent intrinsic energy dissipation mechanism. This paper presents a temperature field in a general trilayered microplate with thermally perfect interfaces based on the integral transform approach. In addition, an analytical model to calculate thermoelastic damping in general trilayered fully clamped microplates is developed. Total thermoelastic damping for trilayered microplates can be expressed as a sum of the normalized energy dissipated in each layer. In order to validate the present model, the results calculated by the present model are compared with those calculated by finite element method (FEM). Our results show that the energy dissipation in the middle part is less than that in the outer parts for homogenous microplates. Thermoelastic damping peaks in trilayered microplates are discussed, which are associated with the critical damping frequency and the Zener's modulus of each layer. When the Zener's modulus of one layer is 2–3 orders of magnitude higher than that of another layer and the critical damping frequency of this layer is also 2–3 orders of magnitude higher than that of another layer, the thermoelastic dissipation spectrum will exhibit multiple peaks. It is also observed that the second layer may exhibit negative energy dissipation in SiC/Ti/Au and Si 3 N 4 /Si/Au trilayered microplates. Graphical abstract It is found that thermoelastic damping spectrum in Si/Si/Ag just contains one peak. However, thermoelastic damping spectrum in Si 3 N 4 /Si 3 N 4 /Ag can exhibit two peaks, though the Zener's modulus of Si is closed to that of Si 3 N 4. Thermoelastic damping spectrums are associated with the critical damping frequency and the Zener's modulus of each layer. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract We present a real-time, high-throughput, and cost-effective method of detecting apoptosis in vitro using a previously developed reagent that detects caspase activation by fluorescence. Current methods of assessing apoptosis fail to account for the dimension of time, and thus are limited in data yielded per sample. This reagent allows real-time detection of apoptosis, but until now has been restricted to a costly automated detection system. Here, we describe apoptosis detection with the Essen Bioscience IncuCyte® Caspase-3/7 Reagent using a multimode microplate reader, a common instrument in biological laboratories, which may be used prior to or in lieu of the automated system. This modified microplate reader apoptosis assay was validated against the established automated system, and was shown to detect a strong dose-response relationship (automated system r2 = 0.9968, microplate reader r2 = 0.9924). We also propose a quick and reliable method of quantifying cell density by Hoechst 33342 nuclear staining in microplates (r2 = 0.8812 between Hoechst signal and cell density). We assert that the dimension of time should not be overlooked, and that the method presented here is an accessible strategy for many researchers due to low startup cost and precise detection of apoptosis in real time. Highlights • Popular methods of apoptosis detection yield a single reading per sample • Accounting for kinetics of the apoptotic response provides more robust and precise data outputs • Current real time methods of apoptosis detection are either expensive or have low sample capacity • A high-throughput microplate reader based assay is shown here to accurately detect apoptosis in real time [ABSTRACT FROM AUTHOR]

A novel and simple method for the measurement of cloud point temperatures of solutions is presented. Cloud point determination, which is currently used to establish the phase diagrams of protein solutions, is indicative of proteins interactions and constitutes a useful tool for food products engineering. We describe a novel experimental setup that allows screening of a large number of physical-chemical conditions in one measurement and the determination of cloud point temperatures both above and below ambient temperature. We use a simple method to avoid solvent evaporation and condensation, so that the set-up can be used for solutions prepared with a volatile solvent. We present the operating parameter range and the precision of the measurement. The optical properties of the system are calibrated with solutions of known transmittance, and the determination of cloud point temperatures is validated on a standard non-ionic surfactant solution. Finally, we demonstrate the efficiency of the method by determining the phase diagram of a wheat protein extract, soluble in a water/ethanol mixture. Complemented with differential scanning calorimetry measurements, the liquid-liquid phase transition can be determined up to a protein concentration of 250 g/L, a range inaccessible with conventional methods for this protein extract. [ABSTRACT FROM AUTHOR]

In order to find insights of plate origin, intraplate deformation and plate driving force, we propose the characteristics and genetic model of microplates which are the residuals of large plates by summarizing previous studies. Subduction-derived Oceanic Microplates (SOMs) are formed in the footwall of the subduction system and generally bounded by spreading ridges, trenches and transform faults when the mid-ocean ridge and subduction zone move towards each other. The identified SOMs are remnants of the Farallon Plate and Phoenix Plate. Large SOMs may fragment further due to the buoyancy of young oceanic crust and subduction velocity difference in response to the interaction between large tectonic plates. Subduction-derived Continental Microplates (SCM) are a type of tectonic feature that originate from the intra-oceanic plate with continental lithosphere. These microplates are typically found in the orogenic belt, which is bounded by suture zones. When the adjacent oceanic crust subduction is entirely consumed through subduction, the plate collides with the hanging wall to form an orogenic belt. The plate is then subject to continuous compression, resulting in crustal shortening and the formation of a strip-shape SCM parallel to the orogenic belt. In the case of the SOMs offshore North America, oceanic crusts with ages below 3–4 Myr can significantly impede subduction, leading to the segmenting of the ridges. By analyzing the spatiotemporal variation of footwall mid-ocean ridge activity, we suggest that the presence of subduction zones is conducive to the seafloor spreading near continental margins. • We put forward the evolution model of microplates which are the residuals of large plates. • The existence of ocean-continent subduction zone enhances the activity of the footwall mid-ocean ridge. • For the Farallon series microplates, 3–4 Myr could be the crust age threshold for whether it is favorable for subduction. [ABSTRACT FROM AUTHOR]

An efficient data collection method is important for microcrystals, because microcrystals are sensitive to radiation damage. Moreover, microcrystals are difficult to harvest and locate owing to refraction effects from the surface of the liquid drop or optically invisible, owing to their small size. Collecting X-ray diffraction data directly from the crystallization devices to completely eliminate the crystal harvesting step is of particular interest. To address these needs, novel microplates combining crystal growth and data collection have been designed for efficient in situ data collection and fully tested at Shanghai Synchrotron Radiation Facility (SSRF) crystallography beamlines. The design of the novel microplates fully adapts the advantage of in situ technology. Thin Kapton membranes were selected to seal the microplate for crystal growth, the crystallization plates can support hanging drop and setting drop vapor diffusion crystallization experiments. Then, the microplate was fixed on a magnetic base and mounted on the goniometer head for in situ data collection. Automatic grid scanning was applied for crystal location with a Blu-Ice data collection system and then in situ data collection was performed. The microcrystals of lysozyme were selected as the testing samples for diffraction data collection using the novel microplates. The results show that this method can achieve comparable data quality to that of the traditional method using the nylon loop. In addition, our method can efficiently and diversely perform data acquisition experiments, and be especially suitable for solving structures of multiple crystals at room temperature or cryogenic temperature.

The increasing concern for food safety has created a need to evaluate novel techniques to eliminate or control pathogens, resulting in safe food. In this study, four bacteriophages of bovine origin, specific to E. coli O157:H7, were successfully isolated and characterized. A microplate reader assay demonstrated the efficacy of the bacteriophage (phage) cocktail against E. coli O157:H7 resulting in a significant reduction (p < 0.01) in the target pathogen population. The phage cocktail demonstrated significant efficacy (p < 0.05) against E. coli O157:H7 in the presence of the most utilized sanitizers in the United States, namely 100 parts per million (ppm) free chlorine and 100-ppm peroxyacetic acid. Survival in the sanitizer concentrations demonstrates the potential use of phage cocktail and sanitizer synergistically to enhance sanitation operations in the food industry.

Accurate methods that can continuously detect low concentrations of hydrogen peroxide (H2O2) have a huge application potential in biological, pharmaceutical, clinical and environmental analysis. Luminescent probes and nanomaterials are used for fabrication of sensors for H2O2 that can be applied for these purposes. In contrast to previous reviews focusing on the chemical design of molecular probes for H2O2, this mini-review highlights the latest luminescent nanoparticular materials and new luminescent optical sensors for H2O2 in terms of the nanomaterial composition and luminescent receptor used in the sensors. The nanomaterial section is subdivided into schemes based on gold nanoparticles, polymeric nanoparticles with embedded enzymes, probes showing aggregation-induced emission enhancement, quantum dots, lanthanide-based nanoparticles and carbon based nanomaterials, respectively. Moreover, the sensors are ordered according to the type of luminescent receptor used within the sensor membranes. Among them are lanthanide complexes, metal-ligand complexes, oxidic nanoparticles and organic dyes. Further, the optical sensors are confined to those that are capable to monitor the concentration of H2O2 in a sample over time or are reusable. Optical sensors responding to gaseous H2O2 are not covered. All nanomaterials and sensors are characterized with respect to the analytical reaction towards H2O2, limit of detection (LOD), analytical range, electrolyte, pH and response time/incubation time. Applications to real samples are given. Finally, we assess the suitability of the nanomaterials to be used in membrane-based sensors and discuss future trends and perspectives of these sensors in biomedical research.

The integrated approach combining kinematic and structural-paragenetic field tectonophysics techniques allows us to construct a continuous time scan of the stress-strain state (SSS) and deformation modes (DM) from sediment lithification to the final orogenic process for the studied areas. Definitions of the continuous sequence of SSS and DM provide for control of the known geodynamic reconstructions and adjustment of geodynamic models. An example is the tectonophysical study of the Alpine structural stage of the Western Mountainous Crimea (WMC) and the Pre-Cambrian complexes of the Ukrainian Shield (USh).Data from WMC allow us to make adjustments to the geodynamic model of the Mountainous Crimea. In particular, trajectories of the principal normal stresses (Fig. 4 and 5), both for shifts and shear faults with reverse components/ normal faults, suggest the reverse nature of movements of the Eastern and Western Black Sea microplates with their overall pushing onto the Crimean peninsula in the south-east, south and south-west (Fig. 7). In the Precambrian USh complexes (Fig. 8), 13 stages of regional deformation are revealed between ≥2.7 and 1.6 billion years ago. Until the turn of 2.05–2.10 billion years, the region was subject to transtension and transpression, as the Western (gneiss-granulite) and Eastern (granite-greenstone) Archean microplates of USh moved to separate from each other in the Neo-Archean and then diverged and converged in the Paleoproterozoic (movements at a sharp angle). It is assumed that in the Archean the Western and Eastern microplates were separated by the oceanic or sub-oceanic lithosphere (Fig. 12, 13). During the period of 2.3–2.4 billion years, the plates fully converged creating a zone of collision. It may be suggested that a possible mechanism for the oceanic window close-up was underthrusting of the upper suboceanic lithosphere layers beneath the crust-mantle plates on gently sloping break-up surfaces (non-subduction option), and one of them is Moho.Spreading of the Western and Eastern microplates of USh began at the turn of 2.05–2.10 billion years, as evidenced by the available tectonophysical data on fields of latitudinal extension of the crust. During spreading 2.1–2.05 billion years ago, emanations and solutions were able to ascend into the upper crust and thus stimulate palingenesis (Novoukrainsky and Kirovogradsky granites), and during repeated spreading 1.75 billion years ago, magma of the basic and acid composition (Pluto gabbro-anorthosite and rapakivi) intruded into the upper crust. The spreading zone coincided with the former collisional suture and became the site wherein the inter-regional Kherson-Smolensk suture was formed; it stretches submeridionally across the East European platform.

Disruptions and perturbations of the cellular plasma membrane by peptides have garnered significant interest in the elucidation of biological phenomena. Typically, these complex processes are studied using liposomes as model membranes-either by encapsulating a fluorescent dye or by other spectroscopic approaches, such as nuclear magnetic resonance. Despite incorporating physiologically relevant lipids, no synthetic model truly recapitulates the full complexity and molecular diversity of the plasma membrane. Here, biologically representative membrane models, giant plasma membrane vesicles (GPMVs), are prepared from eukaryotic cells by inducing a budding event with a chemical stressor. The GPMVs are then isolated, and bilayers are labelled with fluorescent lipophilic tracers and incubated in a microplate with a membrane-active peptide. As the membranes become damaged and/or aggregate, the resulting fluorescence resonance energy transfer (FRET) between the two tracers increases and is measured periodically in a microplate. This approach offers a particularly useful way to detect perturbations when the membrane complexity is an important variable to consider. Additionally, it provides a way to kinetically detect damage to the plasma membrane, which can be correlated with the kinetics of peptide self-assembly or structural rearrangements. Key features • Allows testing of various peptide-membrane interaction conditions (peptide:phospholipid ratio, ionic strength, buffer, etc.) at once. • Uses intact plasma membrane vesicles that can be prepared from a variety of cell lines. • Can offer comparable throughput as with traditional synthetic lipid models (e.g., dye-encapsulated liposomes)., Competing Interests: Competing interestsThe authors declare no competing interests., (©Copyright : © 2023 The Authors; This is an open access article under the CC BY-NC license.)

Background: Heliotropium bacciferum is one of the plants belonging to the family Boraginaceae, which is Restricted distribution in the south of Iran. It is used for Hypotension, fever, stomach ulcers in traditional medicine. Objective: In this study, the antibacterial effects of extracts and fractions of chloroform, ethyl acetate and aqueous, aerial parts of Heliotropium bacciferum Forssk was evaluated against five bacterial strains. Methodes: The methanol extract were prepared using the percolation method. Fractions of chloroform, Petroleum ether, ethyl acetate, methanol and aqueous respectively by Liquid - Liquid fractionation of the total extract were prepared. The antibacterial activity against two Gram positive bacteria, three Gram negative bacterial using Minimum inhibitory concentration in microplate and well plate method. Results: Results showed that H. bacciferum extracts exhibited a significant activity against strains Staphylococcus aureus, Bacillus cereus,Pseudomonas aeruginosa, E.coli and Salmonella enteritidis. MIC and well plate is between 7.6-125 µg/ml. Conclusion: The results of this study indicate that extracts of the plant H.bacciferum has a antimicrobial effect against strains are listed And among the extracts, aqueous part is that most antibacterial effect of the other fraction and then methanolic extract has the greatest effect.

Abstract Any plate has a growth process from small to large. The micro-blocks or micro-plates are sometimes the precursors of large plates. The origin, growth, aborting, extinction and residual process of micro-blocks are of great significance for the study of plate tectonics and pre-plate tectonics. The micro-block can be divided into continental, oceanic and mantle micro-blocks according to their compositions. In this paper, the micro-blocks in the global oceans have been summarized according to the following five environments: mid-ocean ridge system, subduction system, transform fault system, deep-sea intraplate system and extension-rift system. We first propose a genetic classification of micro-blocks comprising: detachment-derived, rifting-derived, transform-derived, propagation-derived, ridge jumping-derived, subduction-derived, accretion-derived, collision-derived and delamination-derived micro-blocks. The different types of micro-block boundaries such as active or fossil detachment fault, subduction zone, mid-ocean ridge, transform fault, fracture zone, transfer fault, accommodation zone, lithosphere-scale strike-slip fault, pseudofault, intra-oceanic convergent zone, overlapping spreading centre, non-transform offset, rheological crustal or mantle discontinuity, are systematically discussed for different micro-blocks. Thus, the number of triple junctions will be more than the 16 in the traditional Plate Tectonic Theory. A stability analysis of these triple junctions is the key to understanding the causes of micro-blocks. However, the micro-block has no ultimate cause, so it is unnecessary to pursue one ultimate cause or initiation of plate tectonics. These micro-blocks within oceanic basins, along oceanic margins or within the deep mantle, can not only be used to develop deep ocean fine structural analysis and plate tectonic reconstruction, but also to explain the causes of micro-blocks in some orogens. This will enrich the research of more detailed pre-orogenic or syn-orogenic evolution of orogenic belts, and even extend to the study of early Precambrian pre-plate tectonic mechanisms. The micro-block can be a transition among microplate, plate and terrane under a plate tectonic regime. It can also be formed in inter-sphere tectonic processes. It helps better our understanding of regimes of cratonic basin formation and intra-continental deformation which are the difficulties faced by the Plate Tectonics Theory. We speculate that the Micro-block Tectonics Theory is a unified tectonic theory of cross-layer, cross-phase, cross-space-time scale and cross-planet. [ABSTRACT FROM AUTHOR]

This paper describes the autocollimation optical scheme of a fluorimeter that allows detecting different reactions from multiple wells of a microplate at the same time. The image focusing is implemented a spherical mirror that excludes the presence of background illumination and chromatic aberration. The operation of the fluorimeter is demonstrated by measuring a signal from the microplate with 96 and 384 individual wells. [ABSTRACT FROM AUTHOR]

Rapid assessment of fungal growth and screening antifungal compounds, such as nanoparticles (NPs), for effectiveness is a challenging procedure because no primary standards exist as they do for yeasts and bacteria. Because fungi do not grow as single cells, but as hyphal filaments, they cannot be quantified by the usual enumeration techniques used in bacteriology. The growth of three postharvest fungal isolates (Alternaria alternata, Rhizopus stolonifer, and Botrytis cinerea) was investigated at different inoculum concentrations and in three nutrient media (Sabouraud dextrose agar, potato dextrose agar, and yeast extract dextrose agar [YED]) with a turbidimetric assay. Sequential measurements were performed to generate optical density versus time plots, whereas the growth responses were expressed quantitatively as the generated trapezoidal area. YED medium showed the lowest variation among replicated experiments; potato dextrose agar showed the next lowest, but there was no significant difference. The inoculum size had a minimal effect on the variation of the fungal dynamics. Microscopic assessment of the fungal growth confirmed that YED medium allowed the most homogeneous development of the studied fungi. Therefore, we developed a rapid and reliable technique to evaluate the efficacy of novel antifungal compounds such as zinc oxide NPs. Turbidimetric assessment showed that these NPs were able to inhibit the growth of all three isolates. A. alternata and B. cinerea did not show a significant difference in the level of inhibition at 15 mM, whereas R. stolonifer showed the highest inhibition at the same concentration. [ABSTRACT FROM AUTHOR]

There has been growing interest in fluorescence-based microplate methods to measure enzyme activities due to the sensitivity of fluorimetric detection and the potential for simultaneous and rapid assaying of multiple enzyme activities in the same soil suspension. However, micro-scale methods could introduce considerable operator error such as: 1) the requirement to put soil samples into a suspension; 2) the very small amounts of soil placed in each microplate well; 3) pipetting error because μL volumes are required; and 4) the need for standard curve calibration with every sample to account for quenching. For valid data comparison and interpretation, there is clearly a need to have a strict and agreed-upon enzyme assay protocol to standardize the microplate-based method. Therefore, the objectives were to: 1) determine the reproducibility and comparability of the standard p -nitrophenol bench-scale and 4-methylumbelliferone microplate enzyme assays measured by five laboratories for β-glucosidase (EC 3.2.1.21) and acid phosphomonoesterase (EC 3.1.3.2) on the same soil samples; and 2) determine the degree and the sources of variability associated with the assays within and among the laboratories. The results showed that overall variability was highest for replication on the microplate (n = 4), whereas suspension replication had low CVs. This suggests an important source of variation is from pipetting not variability from soil suspensions. A major effort was made to control for methodological differences by using air-dried soils (therefore more stable over varying storage periods) and operator consistency for each task across the labs (e.g. preheated reagents, microplate reader sensitivity set to the highest standard, readings taken within an hour of reaction termination, and controls for substrate autohydrolysis). As a result, the differences among labs were much smaller than differences due to soil type for the microplate method, indicating operator error can be minimized by following the same strict protocol. At the molar level, enzyme activity rates measured across the five labs were not the same between bench and MUF microplate methods (although they were within an order of magnitude), but were quite similar in terms of ranking of soil management treatments and soil types ( Table 2 ). Correlations between bench and microplate assays were strong for both enzymes, although slightly stronger for acid phosphomonoesterase (r = 0.93) than β-glucosidase (r = 0.81). Additionally, for both acid phosphomonoesterase and β-glucosidase, correlation r values were mostly similar for MUF microplate and PNP bench method correlation with EL-FAME biomarkers, suggesting both methods were measuring activity originating from the same microbial groups. We conclude that different labs using the same MUF microplate protocol tested, gives reasonably similar absolute activity values, variability, and ranking of treatments (highest to lowest). We propose that the MUF microplate method described in this study be considered as a standard protocol for assaying soil enzyme activities, providing that the buffer pH for the incubation be adjusted to the optimal pH according to the enzyme of interest. [ABSTRACT FROM AUTHOR]

In this paper, a new spectrofluorimetric method for the determination of nitrate in aqueous compost extracts is presented. The microplate procedure is based on the reduction of nitrate to ammonium by means of Zn powder under acidic conditions and the following derivatization of ammonium with o -phthalaldehyde (OPA) and N -acetylcysteine (NAC) to give a fluorescent derivative. Optimization work allowed performing the reduction in 30 min on a small sample volume (150 μL) and using a little quantity of metal (20 mg). The use of strong acids is also avoided. Excellent limit of detection was achieved (1.3 μM = 0.08 mg L −1 NO 3 − ) along with good precision levels (4.2 and 14.3% for 50 and 5 μM, respectively) and a satisfactory linear dynamic range (4–100 μM). A good agreement between data coming from our method and from ion-exchange chromatography was found on real compost samples, indicating a good level of accuracy. [ABSTRACT FROM AUTHOR]

The micropolar theory (MPT), through taking the rotational degrees of freedom of material particles into account, is a suitable elasticity theory for the mechanical analysis of microstructures. In this article, the vibration behavior of microscale beams and plates is studied based on MPT. To this end, first, a three-dimensional (3D) formulation is developed for the micropolar continua which can be readily used in the finite element analyses. Then, a non-classical 3D element is introduced to investigate the free vibration characteristics of micropolar beams and plates. The microstructure effect on the frequencies of microbeams and microplates under different kinds of boundary conditions is illustrated. Also, the results of MPT are compared with those of classical theory and it is indicated that there is a considerable difference between their predictions at small scales. [ABSTRACT FROM AUTHOR]

Enzyme activity as a method for soil biochemistry and microbiology research has a long history of more than 100 years that is not widely acknowledged in terms of adherence to strict assay protocols and the interpretation of results. However, in the recent past, there is a growing lack of recognition of the historic advancements among researchers that use soil enzymology. Today, many papers are being published that use methods that either do not follow exact protocols as originally vetted in the research literature or individual labs use their own method that has not been optimized for pH, co-factors, substrate concentrations, or other conditions. This is of particular concern for fluorogenic substrates and microplate methods. Furthermore, there is a lack of understanding of the origin and location of a given enzyme being studied. Notably, regardless of the enzyme, it is too often assumed that enzyme activity equals microbial activity-which is not the case for most hydrolytic enzyme assays. Because as established by Douglas McLaren in the 1950s, a considerable amount of activity can come from catalytic enzymes stabilized in the soil matrix but that are no longer associated with viable cells (known as abiontic enzymes). In summary, today, many papers are using imperfect methods and/or misinterpret enzyme activity data that at a minimum confounds cross paper studies and meta-analysis. However, most importantly, lack of historical perspectives and ignoring strict protocols cause redundancy and fundamentally undermine the discipline and understanding of soil microbiology/biochemistry when enzymology methods are used. [ABSTRACT FROM AUTHOR]

This paper proposes the use of microplates as a new flow control device to suppress boundary layer separation on blades and thus improve the aerodynamic performance of a low-speed axial flow fan. A computational study is performed by means of computational fluid dynamics (CFD) simulations. Numerical investigations are carried out based on Reynolds-averaged Navier-Stokes (RANS) method. The shear stress transport (SST) turbulence model and high-quality computational grids are adopted for CFD simulations. An exhaustive comparison of the fans with and without control has been conducted in terms of characteristic curves, streamlines and pressure distributions. The purpose of this work is to better understand the underlying flow control mechanisms of microplates. It is found that the total efficiency is slightly lowered when the controlled fan operates at the design flow rate. However, as the flow rate changes, the total efficiency of the controlled fan varies more gently than the original fan without control. Traced streamlines show that flow separation on blade surfaces is effectively controlled and radial flow migration on the suction surface is evidently diminished. Numerical results indicate that microplates significantly alleviate fan stall and have considerable beneficial effects on fan performance. [ABSTRACT FROM AUTHOR]

The present study uses the isogeometric analysis (IGA) to investigate the post-buckling behavior of functionally graded (FG) microplates subjected to mechanical and thermal loads. The modified a strain gradient theory with three length scale parameters is used to capture the size effect. The Reddy third-order shear deformation plate theory with the von Kámán nonlinearity (i.e., small strains and moderate rotations) is employed to describe the kinematics of the microplates. Material variations in the thickness direction of the plate are described using a rule of mixtures. In addition, material properties are assumed to be either temperature-dependent or temperature-independent. The governing equations are derived using the principle of virtual work, which are then discretized using the IGA approach, whereby a C 2 -continuity requirement is fulfilled naturally and efficiently. To trace the post-buckling paths, Newton’s iterative technique is utilized. Various parametric studies are conducted to examine the influences of material variations, size effects, thickness ratios, and boundary conditions on the post-buckling behavior of microplates. [ABSTRACT FROM AUTHOR]

In the study, three different higher order finite element models (HOFEMs) are developed to perform the transient analysis of functionally graded (FG) microplates subjected to different dynamic loads, namely, sinusoidally distributed step and exponential blast loads. A normal and shear deformable plate theory with five unknowns is used to present displacement field and modified strain gradient theory is employed for small-scale effect. A rectangular four-noded element and Newmark's method is used to solve transient analysis of FG microplates. The effects of boundary condition, type of dynamic loading, thickness to material length parameter, aspect ratio, gradient index and CPU time are investigated. It is found that two of the HOFEMs developed based on the C1 and C2 continuity requirements produced almost same numerical results. However, the one with 36 unknows per element yields slightly different results than the others. The HOFEM satisfying the C1 continuity requirement consumes the minimum computational time. • Three different higher order finite element models (HOFEMs) are developed. • Transient analysis of FGM microplates is performed by using the MSGT. • Sinusoidally distributed step and sinusoidally distributed exponential blast loads are applied. • A normal and shear deformable plate theory with five unknowns is used. [ABSTRACT FROM AUTHOR]

In this study, siderophore production by various bacteria amongst the plant-growth-promoting rhizobacteria was quantified by a rapid and efficient method. In total, 23 siderophore-producing bacterial isolates/strains were taken to estimate their siderophore-producing ability by the standard method (chrome azurol sulphonate assay) as well as 96 well microplate method. Production of siderophore was estimated in percent siderophore unit by both the methods. It was observed that data obtained by both methods correlated positively with each other proving the correctness of microplate method. By the modified microplate method, siderophore production by several bacterial strains can be estimated both qualitatively and quantitatively at one go, saving time, chemicals, making it very less tedious, and also being cheaper in comparison with the method currently in use. The modified microtiter plate method as proposed here makes it far easier to screen the plant-growth-promoting character of plant-associated bacteria. [ABSTRACT FROM AUTHOR]

Human cell cultures provide a potentially powerful means for pharmacological and toxicological research. A microplate with a multielectrode array of 96 organic electrochemical transistors (OECTs) based on the semiconductive polymer poly(3,4-ethylenedioxythio-phene):poly (styrene sulfonic acid) PEDOT:PSS was developed and fabricated by the screen printing method. It consists of a microplate of a 12 x 8 chimney--well array with transistors on the bottom. The OECT is circular with a channel of 1.5 mm² in the centre surrounded by the circular gate electrode. The device is designed for electrogenic cell monitoring. Simulations with the electrolyte revealed good electrical characteristics and indicated the setup information of the experimental conditions. A transconductance of g = 1.4 mS was achieved in the wide range of gate voltages Vgs = ±0.4 V when the drain potential Vds = -0.735 V was set and the long term relaxation was compensated for. The time constant 0.15 s limited by the channel-electrolyte charge electrical double layer (EDL) capacitance was measured. The device was tested on a 3T3 fibroblast cell culture and the sudden environmental changes were recorded. The living cells can be observed on the channel of the OECT and during electrical stimulation by gate voltage, as well as during the source current response. [ABSTRACT FROM AUTHOR]

This paper analyzes the effect of squeeze film and size effect on dynamic response of microplate. The microplate in this work is a clamped-clamped plate, which is excited using electrostatic force. The gap between microplate and substrate is filled with air. First order shear deformation theory (FSDT) and couple stress theory (CST) and considering Von Karman's strains are used to model the equation of motion of microplate. Non-linear Reynolds equation based on Micropolar theorem is deployed to apply the size effect on the fluid. Afterward, Equations are discretized by applying couple finite element method and finite difference method. The first-order differential equations are solved utilizing Newmark's method. One of the contributions is presenting the influences of size effect and mid-plane stretching on the microplate dynamic behavior, also the influence of different parameters on the quality factor. According to the results, mid-plane stretching effect increases the microplate rigidity. Interestingly, this effect is more dominant for voltages with higher amplitude. This paper emphasizes that considering the plate size effect will increase the rigidity of the system. Moreover, the plate size effect increases the rigidity of the system whereas the fluid size effect decreases it. Increasing the fluid's pressure results in decrease in the amplitude of oscillations in step voltage excitation which postpones the dynamic pull-in. This paper concludes that increasing the coupling parameter of fluid increases the natural frequency of microplate, whereas increasing the fluid length scale parameter decreases the natural frequency and quality factor of the system. [ABSTRACT FROM AUTHOR]

Background: Improved methods with better separation and concentration ability for detection of foodborne pathogens are in constant need. The aim of this study was to evaluate microplate immunocapture (IC) method for detection of Salmonella Typhi, Shigella flexneri and Vibrio cholerae from food samples to provide a better alternative to conventional culture based methods. Results: The IC method was optimized for incubation time, bacterial concentration, and capture efficiency. 6 h incubation and log 6 CFU/ml cell concentration provided optimal results. The method was shown to be highly specific for the pathogens concerned. Capture efficiency (CE) was around 100% of the target pathogens, whereas CE was either zero or very low for non-target pathogens. The IC method also showed better pathogen detection ability at different concentrations of cells from artificially contaminated food samples in comparison with culture based methods. Performance parameter of the method was also comparable (Detection limit- 25 CFU/25 g; sensitivity 100%; specificity-96.8%; Accuracy-96.7%), even better than culture based methods (Detection limit- 125 CFU/25 g; sensitivity 95.9%; specificity-97%; Accuracy-96.2%). Conclusion: The IC method poses to be the potential to be used as a method of choice for detection of foodborne pathogens in routine laboratory practice after proper validation. [ABSTRACT FROM AUTHOR]

To obtain maximal linear regression correlation coefficient ( R ) of glucose standard curve determinations, single-factor test and response surface methodology were applied to optimize conditions including reaction time, incubation temperature and phenol concentration. For investigating optimization of this method, the effects of different metal ions, amino acids and proteins, respectively, were evaluated. The contents of several polysaccharides were determined by three methods, and it was found that the absorption value at 490 nm of the reaction system (230 μL) placed in the microplate involving 150 μL sulfuric acid and 30 μL 5 % phenol solution was in linear relationship with the concentration of glucose range from 10 to 100 nmol/well at 85 °C for 20 min. Our results also suggested that the method had a relative deviation of 0.4 %, and the recovery was between 102.7 and 104.10 %. [ABSTRACT FROM AUTHOR]

In this paper, an improved spectrofluorimetric method for the simultaneous and direct determination of ammonium and primary amine compounds is presented. The method is based on the derivatization of the analytes with o -phthaldialdehyde (OPA)/ N -acetylcysteine (NAC) reagent using high throughput microplates, and OPA/NAC ratio has been optimized in order to suppress interference of ammonium on primary amine determination. Direct measurement of these two parameters is therefore possible with a global procedure time that does not exceed 10 min. Excellent limits of detection of 1.32 μM and 0.55 μM have been achieved for ammonium and primary amines, respectively. Reagent stability issues have also been addressed and formulation of reagents solution is described for improved reagents shelf life. The proposed protocol was finally applied and validated on real samples such as wine samples, compost extracts and wastewater. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have key roles in gene expression and can be employed as biomarkers for early diagnosis of various diseases, especially cancers. Detection of miRNAs remains challenging and often requires detection platforms. Here, a horseradish peroxidase (HRP)-assisted hybridization chain reaction (HCR) for colorimetric detection of miR-155 was described. In the presence of target miRNA, the capture probe immobilized on the microplate sandwiched the target miR-155 with the 3′ end of the reporter probe. Another exposed part of the RP at the 5'end triggered HCR producing double-stranded DNA polymers with multiple fluorescein isothiocyanates (FITC) for signal amplification. Finally, multiple HRP molecules were immobilized onto the long-range DNA nanostructures through FITC/anti-FITC monoclonal antibody interactions on the microplate for visualization by tetramethylbenzidine/H 2 O 2 system and the colorless substrate turned into the blue product. To obtain accurate data, the absorbance at 450 nm was calculated by microplate reader. The detection limit was 31.8 fM (3.18 amol). Furthermore, this biosensor showed high specificity and was able to discriminate sharply between target miRNA and mismatched sequences. And this approach could be easily applied to the detection of miR-155 in serum sample, thereby ascribing it for a wide application. [ABSTRACT FROM AUTHOR]

Sessile drops, based on water–glycerol mixtures at 40 μL, deposited on solid substrates were studied as they were accelerated upwards and then stopped suddenly to create an upward longitudinal impact effect. By varying the initial start positions of the platform in the setup, controlled impact momentums of up to 4.31 × 10 −3 Ns could be attained. Three categories of drop behavior, labeled I to III, were uncovered. On the non-scribed substrate types I and II drop behavior were found, whereas all types of demeanor were exhibited by the scribed surface. On the scribed surface, the contact angle is able to recede more (by 20̊) than on the non-scribed surface (by 15̊). This is primarily due to the strong contact line pinning offered by the parapet and steep scarp formed around the groove. Since the liquid body is able to attain a lower receding contact angle on the scribed surface, this will allow higher adhesion effect of its lower portion even as the upper portion seeks to separate. This manifests in a greater propensity for the liquid body to neck and thus for separation to occur. Numerical simulations reveal the tendency of the separated drops to develop circulations that change direction as they coalesce. There is therefore potential for increased mixing using this mode. [ABSTRACT FROM AUTHOR]

With microplate-immobilized polyclonal antibodies against a starting enzyme or its active mutant bearing consistent accessible epitopes, the maximum activity of an adsorbed enzyme/mutant ( Vs) was predicted for comparison to recognize weakly-positive mutants. Rabbit antisera against Escherichia coli alkaline phosphatase (ECAP) were fractionated with 33% ammonium sulfate to yield crude polyclonal antibodies for conventional immobilization in 96-well microplates. The response curve of the activities of ECAP/mutant adsorbed by the immobilized polyclonal antibodies to protein quantities from a cell lysate was fit to an approximation model to predict Vs. With 0.4 μg crude polyclonal antibody for immobilization, Vs was consistent for ECAP in cell lysates bearing fourfold differences in its apparent specific activities when its abundance was greater than 0.9%. The ratio of Vs of the mutant R168K to that of ECAP was 1.5 ± 0.1 ( n = 2), consistent with that of their specific activities after affinity purification. Unfortunately, the prediction of Vs with polyclonal antibodies that saturated microplate wells was ineffective to Pseudomonas aeruginosa arylsulfatase bearing less than 2% specific activity of ECAP. Therefore, with microplate-immobilized polyclonal antibodies to adsorb enzyme/mutants from cell lysates, high-throughput prediction of Vs was practical to recognize weakly-positive mutants of starting enzymes bearing fairly-high activities. [ABSTRACT FROM AUTHOR]

Background: We developed and validated a kinetic microplate hemolytic assay (HA) to quantify classical and alternative complement activity in a single dilution of human plasma or serum. Methods: The assay is based on monitoring hemolysis of sensitized sheep (or uncoated rabbit) red blood cells by means of a 96-well microplate reader. The activity of the calibrator was evaluated by reference to 200 healthy adults. The conversion of 50% hemolysis time into a percentage of activity was obtained using a calibration curve plotted daily. Results: The linearity of the assay as well as interference (by hemolysis, bilrubinemia and lipemia) was assessed for classical pathway (CP). The within-day and the betweenday precision was satisfactory regarding the performance of commercially available liposome immunoassay (LIA) and ELISA. Patients with hereditary or acquired complement deficiencies were detected (activity was measured < 30%). We also provided a reference range obtained from 200 blood donors. The agreement of CP evaluated on samples from 48 patients was 94% with LIA and 87.5% with ELISA. The sensitivity of our assay was better than that of LIA, and the cost was lower than either LIA or ELISA. In addition, this assay was less time consuming than previously reported HAs. Conclusions: This assay allows the simultaneous measurement of 36 samples in duplicate per run of a 96-well plate. The use of a daily calibration curve allows standardization of the method and leads to good reproducibility. The same technique was also adapted for the quantification of alternative pathway (AP) activity. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid perovskites attract considerable attention owing to their applications in high-efficiency solar cells and light emission. Compared with three-dimensional perovskites, two-dimensional (2D) layered hybrid perovskites have a higher exciton binding energy and potentially higher light-emission efficiency. The growth of high-quality crystalline 2D perovskites with a well-defined nanoscale morphology is desirable because they can be suitable building blocks for integrated optoelectronics and (nano)photonics. Herein, we report the facile solution growth of single-crystal microplates of 2D perovskites based on a 2-phenylethylammonium (CHCHCHNH, PEA) cation, (PEA)PbX (X = Br, I), with a well-defined rectangular geometry and nanoscale thickness through a dissolution-recrystallization process. The crystal structures of (PEA)PbX are first confirmed using single-crystal X-ray diffraction. A solution-phase transport-growth process is developed to grow microplates with a typical size of tens of micrometers and thickness of hundreds of nanometers on another clean substrate different from the substrate coated with lead-acetate precursor film. Surface-topography analysis suggests that the formation of the 2D microplates is likely driven by the wedding-cake growth mechanism. Through halide alloying, the photoluminescence emission of (PEA)Pb(Br,I) perovskites with a narrow peak bandwidth is readily tuned from violet (~410 nm) to green (~530 nm). [ABSTRACT FROM AUTHOR]

In the present paper, static bending and forced vibration of an imperfect FG microplate carrying a moving load are dealt with based on Mindlin plate theory (MPT) and the modified couple stress theory (MCST). The material properties of FG microplate change continuously along thickness direction according to simple power law. The concept of neutral surface is used to eliminate stretching-bending coupling. The imperfection of the microplate is caused by the porosities that may occur inside FG material during the fabrication. The energy approach basis on the Lagrange equations is used to obtain the response of FG microplate. The trial functions denoting the transverse deflection and the rotations about x and y coordinates are expanded into the series using the two dimensional polynomials to acquire the approximate solution. An efficient and simple method is presented to satisfy the various boundary conditions with the help of some auxiliary functions in the trial functions. The equations of motion of FG microplate are solved in time domain by means of Newmark’s method. The effects of the material variation, porosity volume fraction and porosity scheme, length scale parameter and the velocity of the moving load on the dynamic responses are investigated. Besides, the reliability of the present formulation and the computer codes developed by the authors is established by using the static responses of FG microplate. [ABSTRACT FROM AUTHOR]