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In this paper, we consider the uniqueness issue for the inverse problem of load identification in a nanoplate by dynamic measurements. Working in the framework of the strain gradient linear elasticity theory, we first deduce a Kirchhoff‐Love nanoplate model, and we analyze the well‐posedness of the equilibrium problem, clarifying the correct Neumann conditions on curved portions of the boundary. Our uniqueness result states that, given a transverse dynamic load ∑m=1Mgm(t)fm(x)$$ {\sum}_{m=1}^M{g}_m(t){f}_m(x) $$, where M≥1$$ M\ge 1 $$ and {gm(t)}m=1M$$ {\left\{{g}_m(t)\right\}}_{m=1}^M $$ are known time‐dependent functions, if the transverse displacement of the nanoplate is known in an open subset of its domain for any interval of time, then the spatial components {fm(x)}m=1M$$ {\left\{{f}_m(x)\right\}}_{m=1}^M $$ can be determined uniquely from the data. The proof is based on the spherical means method. The uniqueness result suggests a reconstruction technique to approximate the loads, as confirmed by a series of numerical simulations performed on a rectangular clamped nanoplate. [ABSTRACT FROM AUTHOR]

Premise: Phosphorus (P) is an essential macronutrient that is often limited in agricultural systems. Determining inorganic phosphate (Pi) contents of plant tissues is crucial for evaluating plant P status. Here, we present a simple, high‐throughput colorimetric microplate technique to measure Pi contents in rice (Oryza sativa) leaf tissues, based on the molybdenum blue reaction. Methods and Results: We used a hole puncher to sample small equal areas of leaf tissue for Pi extraction. We removed the leaf grinding and weighing steps, which are time‐consuming and normally required to release Pi from the tissues and to measure the biomass for data normalization, respectively. We showed that the punching method yielded comparable results to the conventional grinding method for two rice cultivars grown under various levels of P supply. Conclusions: Compared with existing techniques, this protocol is more suited to an initial screening, enabling one researcher to determine the Pi contents of thousands of rice leaf samples within a few hours. [ABSTRACT FROM AUTHOR]

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]

ABSTRACT High throughput protein production from transient transfection of mammalian cells is used in multiple facets of research and development studies. Commonly used formats for these high number expressions are 12-, 24- and 96-well plates at various volumes. However there are no published examples of a 96-deep well plate microscale (1,000 μL) suspension process for mammalian transient expression. For this reason, we aimed to determine the optimal operating conditions for a high producing, microscale HEK293 transient system. We evaluated the hydrodynamic flow and measured the oxygen transfer rate (OTR) and transient protein expression for 96-deep well plates of different well geometries filled at 600-1,000 μL working volumes and agitated at various speeds and orbital diameters. Ultimately, a round well-round bottom (RR) 96-deep well plate with a working volume of 1,000 µL agitated at 1,000 RPM and a 3 mm orbital diameter yielded the highest and most consistent total transient protein production. As plate cultures are subject to evaporation, water loss from different plate seals was measured to identify an optimal plate sealing method. Finally, to enable higher capacity protein production, both expression and purification processes were automated. Functionality of this end-to-end automation workflow was demonstrated with the generation of high levels of human IgG1 antibodies (≥360 µg/mL) with reproducible productivity, product quality and ≥78% purification recovery. Biotechnol. Bioeng. 2015;112: 1832-1842. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background Non-structural carbohydrate ( NSC; glucose, fructose, sucrose and fructan) composition of onions ( Allium cepa L.) varies widely and is a key determinant of market usage. To analyse the physiology and genetics of onion carbohydrate metabolism and to enable selective breeding, an inexpensive, reliable and practicable sugar assay is required to phenotype large numbers of samples. Results A rapid, reliable and cost-effective microplate-based assay was developed for NSC analysis in onions and used to characterise variation in tissue hexose, sucrose and fructan content in open-pollinated breeding populations and in mapping populations developed from a wide onion cross. Sucrose measured in microplates employing maltase as a hydrolytic enzyme was in agreement with HPLC-PAD results. The method revealed significant variation in bulb fructan content within open-pollinated 'Pukekohe Longkeeper' breeding populations over a threefold range. Very wide segregation from 80 to 600 g kg−1 in fructan content was observed in bulbs of F2 genetic mapping populations from the wide onion cross 'Nasik Red × CUDH2150'. Conclusion The microplate enzymatic assay is a reliable and practicable method for onion sugar analysis for genetics, breeding and food technology. Open-pollinated onion populations may harbour extensive within-population variability in carbohydrate content, which may be quantified and exploited using this method. The phenotypic data obtained from genetic mapping populations show that the method is well suited to detailed genetic and physiological analysis. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

High-throughput platforms for microalgae screening are not yet commercially available. In this study, the feasibility of 96-well microplates was analyzed for microalgae research. Equivalence among wells, as culture microreactors, was investigated in controlled high CO2 conditions. Specific growth rates of two microalgae species, Scenedesmus sp. UTEX1589 and an environmental isolate, were significantly higher in border wells than in internal positions. Furthermore, growth rate gradients analyzed as contours throughout the platform were observed for Scenedesmus sp. However, the output variable exhibited high precision associated with a low coefficient of variation (CV), between 6.8 and 7.8%. In a demonstrative experiment to determine the effect of culture media dilution on six microalgae species, treatments were randomized in the central subset of a microplate. Results were consistent and statistically sound (CV 9.4-12.9%), and showed that microalgae species could grow with no detrimental effect in 50% (v/v) dilution of the culture medium. Provided border wells exclusion and a randomized design, 96-well microplates are a practical and statistical robust platform for microalgae research. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:638-644, 2013 [ABSTRACT FROM AUTHOR]

ABSTRACT A 96-well microplate-based HPLC endpoint assay is described for the determination of NADPH-cytochrome P450 reductase (CPR) activity. Novel sampling of NADPH into microplates was optimized. Separation was performed on a Zorbax Eclipse XDB-C18 analytical 4.6 × 150 mm, 5 µm column. To validate the method, recombinant human NADPH-P450 reductase and microsomes with cytochrome P450 CYP1A1 were used. The mobile phase consisted of 80% acetonitrile and 20% water at a flow-rate of 0.8 mL/min. The CPR activity was quantified using NADPH fluorescence at λEx = 340 nm and λEm = 450 nm. Enzymatic activity was directly proportional to the decrease in NADPH fluorescence. This analytical process enables a highly sensitive endpoint determination for reductase activity in vitro and monitoring of the consumption of NADPH in enzymatic reactions. The method avoids the use of substrates and of organic solvents that may affect CPR and cytochrome P450 activity. In the reaction, molecular oxygen served as a proton source. The method can substitute spectrophotometric detection methods for its accuracy, high reproducibility (~100%) and sensitivity. The lower limit of detection, shown using the Agilent 1200 aparatus, is in the 250 nmol range. In addition, using this method it is possible to set up reactions in a high-throughput format. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Active mountain building associated with the accretion of the Yakutat microplate (YT) in southern Alaska is characterized through the combination of a new balanced cross section and new low-temperature cooling ages. This analysis constrains the amount and timing of shortening, the spatial and temporal trends of exhumation, and the interplay between structural development and exhumation. A fold-and-thrust belt comprising three principal thrust sheets (the Hope Creek, Sullivan, and an offshore thrust sheet from north to south) characterizes the YT internal structure, which has absorbed a minimum of ∼82 km shortening. Assuming shortening and foreland basin development occurred contemporaneously, the shortening rate across the YT is ∼13-14 mm/a after 5.6 Ma. Detrital apatite fission track ages, from south to north, are unreset along the southern edge of the Sullivan thrust sheet at the coast, are reset and have ages younger than 6.3 Ma within the thrust belt, and have reset cooling ages of ∼13 Ma in the North American upper plate. Only the zircon samples from the northern, internal YT are potentially reset. Exhumation rates within the thrust belt vary from 0.3 ± 0.1 mm/a to 4 ± 1.8 mm/a. Combining the thermochronometric and structural data indicate that wedge exhumation since ∼6 Ma is 500 km2 and that particle trajectories have larger horizontal than vertical components. Whereas exhumation and shortening have been focused on the windward side of the Chugach/St. Elias Range since ∼6 Ma, the cooling ages do not uniquely distinguish between orographically versus tectonically controlled erosion. [ABSTRACT FROM AUTHOR]

D-ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyses the first step in photosynthetic carbon assimilation and represents the largest sink for nitrogen in plants. Improvement of its kinetic properties or the efficiency with which it is used in planta would benefit photosynthesis, nitrogen and water use efficiency, and yield. This paper presents a new non-radioactive microplate-based assay, which determines the product [3-phosphoglycerate (3-PGA)] in an enzymic cycle between glycerol-3-phosphate dehydrogenase and glycerol-3-phosphate oxidase. High sensitivity permits use of highly diluted extracts, and a short reaction time to avoid problems due to fall-off. Throughput was several hundreds of samples per person per day. Sensitivity and convenience compared favourably with radioisotopic assays, which were previously used to assay Rubisco. Its use is illustrated in three applications. (1) Maximal and initial activities and the Km for ribulose-1,5-bisphosphate were determined in raw extracts of leaves from several species. Similar values were obtained from those in the literature. (2) Diurnal changes were compared in rosettes of wild-type (WT) Arabidopsis and the starchless pgm mutant. Despite these dramatic differences in carbon metabolism, Rubisco activity and activation were similar in both genotypes. (3) A preliminary association mapping study was performed with 118 Arabidopsis accessions, using 183 markers that probably cover ∼3–8% of the total genome. At a P-value < 0.005, two, two and no quantitative trait loci (QTL) were found for Rubisco maximal activity, initial activity and activation state, respectively. Inspection of the genomic regions that span these markers revealed these QTL involved genes not previously implicated in the regulation of Rubisco expression or activity. [ABSTRACT FROM AUTHOR]

Objective: Urethritis is not always caused by a single pathogen, and isolation of more than two pathogens from one patient is not uncommon. We developed a method to simultaneously detect 16 pathogens related to urethritis. Methods: We designed specific primers used for amplification of urethritis pathogens in our 16-well microplate assay. Sixteen microliters of each reaction mixture containing template DNA was added to each well to amplify 16 pathogens simultaneously. Results: After we evaluated the specificity and sensitivity of this microplate polymerase chain reaction method, we used it to detect pathogens in clinical samples. Of 163 clinical samples, 49.7% (81/163) were positive for specific pathogens, and 6.7% (11/163) showed mixed infection. A specific pathogen was not identified in 43.6% (71/163) of cases. Conclusions: We developed a 16-well microplate assay with 16 specific primers to identify pathogens associated with urethritis. [ABSTRACT FROM AUTHOR]

Premise of the Study: Current methods for quantifying herbivore‐induced alterations in plant biochemistry are often unusable by researchers due to practical constraints. We present a cost‐effective, high‐throughput protocol to quantify multiple biochemical responses from small plant tissue samples using spectrophotometric techniques. Methods and Results: Using Solanum lycopersicum and Medicago polymorpha leaves pre‐ and post‐herbivory, we demonstrate that our protocol quantifies common plant defense responses: peroxidase production, polyphenol oxidase production, reactive oxygen species production, total protein production, and trypsin‐like protease inhibition activity. Conclusions: Current protocols can require 500 mg of tissue, but our assays detect activity in less than 10 mg. Our protocol takes two people 6 h to run any of the assays on 300 samples in triplicate, or all of the assays on 20 samples. Our protocol enables researchers to plan complex experiments that compare local versus systemic plant responses, quantify environmental and genetic variation, and measure population‐level variation. [ABSTRACT FROM AUTHOR]

Electrical properties of undoped and Mn doped SnO2 microplates and rods are studied by electron beam induced current (EBIC) in a scanning electron microscope (SEM), and I–V curves acquired at room temperature. AFM measurements reveal the formation of numerous terraces at the (−101) surface of the analyzed Mn‐doped SnO2 microplates, which also exhibit high carrier recombination processes at their central region, as confirmed by combined EBIC and cathodoluminescence (CL) measurements. A diffusion length for minority carriers about 205 nm is obtained by EBIC measurements. Different electrical conduction mechanisms, such as Fowler‐Nordheim, direct tunneling and Poole‐Frenkel, are evaluated in the electrical analysis of the samples. Mn doped microplates show lower conductivity than the undoped microds. Moreover the height of the surface tunnel barrier is increased by Mn doping, as confirmed by the analysis of the I–V curves acquired under transversal configuration. A value of the relative dielectric constant ϵr about 7.3 is estimated for the probed SnO2 microstructures. An electrically characterization of undoped and Mn doped SnO2 microplates and rods, grown by a vapor–solid process, is performed. Mn doping induces a decrease in the electrical conductivity, as well as an increase of the surface dielectric tunnel barrier estimated from the analysis of the direct tunneling mechanism observed in the I–V curves. [ABSTRACT FROM AUTHOR]

Single laboratory method performance parameters, including the calibration curve, accuracy, recovery, precision, limit of detection (LOD), and limit of quantification (LOQ), were evaluated for the analysis of total food folate by the trienzyme extraction and microplate assay with Lactobacillus casei subsp. rhamnosus. Standard Reference Material (SRM) 1546 (meat homogenate), SRM 2383 (baby food composite), SRM 1846 (infant formula), Certified Reference Material (CRM) 121 (wholemeal flour), and CRM 485 (mixed vegetables), representing a broad selection of food matrices, were used to evaluate the performance of the method. A generated 4-parameter logistic equation of the calibration curve was y= (0.0705 − 1.0396)/(1 + ( x/0.0165) 1.3072) + 1.0396 ( P < 0.0001). The test of parallelism demonstrated that matrix components in the food extracts did not affect the accuracy. Measured values of the SRMs and CRMs were within their certified or reference values. Recoveries for all reference materials met the requirements of the AOAC guidelines for single laboratory validation. Precision measured as repeatability, including simultaneous and consecutive replicates for each SRM and CRM, met the Horwitz criterion. LOD and LOQ values were 0.3 and 0.6 μg/100 g, respectively. The results showed that trienzyme digestion using α-amylase, PronaseR, and conjugase from chicken pancreas coupled with a 96-well microplate assay provided a highly accurate, reproducible, and sensitive method for the determination of folate in a variety of foods. [ABSTRACT FROM AUTHOR]

Biological assays using aquatic invertebrates and fish do not necessarily predict protection levels for primary producers such as algae and aquatic macrophytes. State regulatory programs may not be protecting the environment from many phytotoxic compounds. Recent modifications of the U.S. Environmental Protection Agency's algal test were evaluated for their potential use as a regulatory assay. Primary goals ofthis investigation were to downsize the algal assay and to evaluate various methods of automation. Disposable microplates with 2-ml sample wells were evaluated as an alternative testing chamber for the 96-hgrowth inhibition test with Raphidocelis subcapitata (formerly knownas Selenastrum capricornutum). We compared the standardized Erlenmeyer(r) flask test to the microplate test using CuCl2, NaCl,phenol, ZnCl2, and a surfactant. We noted improved control performance with the microplate test, whereas median inhibitory concentration values were similar for both methods. Other procedures we addressed included the use of EDTA, filtration of samples, and the effect of colored samples on algal growth. We also evaluated growth estimates by comparing manual cell counting to more automated growth estimates using fluorescence and absorbance endpoints. The use of fluorescence and absorbance measurements demonstrated reductions in replicate variability over manual counting and may offer time-saving alternatives for laboratory analysts. [ABSTRACT FROM AUTHOR]