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A Lewis acid promoted intramolecular Schmidt reaction of N-acylbenzotriazoles with alkyl azides was designed and realized. The benzotriazole was not only employed as an efficient activator for initiating the Schmidt rearrangement but also used as a powerful terminator for the subsequent nucleophilic trapping of the isocyanate ion and/or N-acyliminium ion from the rearrangement. Thirteen δ-azido N-acylbenzotriazoles were investigated, and the conversion afforded the desired benzotriazole-1-carboxamides and lactams with good to excellent yields.

Plasmonic nanolasers are a new class of laser devices which amplify surface plasmons instead of photons by stimulated emission. A plasmonic nanolaser cavity can lower the total cavity loss by suppressing radiation loss via the plasmonic field confinement effect. However, laser size miniaturization is inevitably accompanied with increasing total cavity loss. Here we reveal quantitatively the loss and gain in a plasmonic nanolaser. We first obtain gain coefficients at each pump power of a plasmonic nanolaser via analyses of spontaneous emission spectra and lasing emission wavelength shift. We then determine the gain material loss, metallic loss and radiation loss of the plasmonic nanolaser. Last, we provide relationships between quality factor, loss, gain, carrier density and lasing emission wavelength. Our results provide guidance to the cavity and gain material optimization of a plasmonic nanolaser, which can lead to laser devices with ever smaller cavity size, lower power consumption and faster modulation speed.

Selenium (Se) is one of the essential elements required to maintain human health. Although various kinds of Se supplements are now available on the market, their biological activities and toxicities vary based on the transportation characteristics of Se. In this study, we compared the absorption and distribution of Se in rats administered with different Se supplements: Se-enriched Bifidobacterium longum DD98 (Se-DD98), selenized yeast (Se-Y), and sodium selenite (Na2SeO3). Se-DD98, Se-Y, and Na2SeO3 were orally administered to rats. The plasma Se content at different time points after administration was determined within 72 h. Pharmacokinetic parameters were analyzed to reveal the absorption of Se. Se-DD98, Se-Y, and Na2SeO3 were also repeatedly administered by oral gavage for 30 days, and Se content of the heart, liver, spleen, lungs, kidneys, and muscle was determined to analyze the distribution of Se. The results showed that the organic Se supplements (Se-DD98 and Se-Y) were more easily absorbed into the blood and retained longer in the plasma than the inorganic Na2SeO3 was. Moreover, Se-DD98 induced better absorption of Se in plasma than Se-Y did. Furthermore, significantly higher concentrations of Se were found in the heart, liver, spleen, kidneys, and muscle of rats administered with organic Se supplements (Se-DD98 and Se-Y) than those administered the inorganic Na2SeO3. Rats administered Se-DD98 accumulated more Se in the spleen, lung, and kidney than those administered Se-Y, while Se-Y led to higher concentration of Se in the liver compared to Se-DD98. These results suggest that the organic form of Se was better absorbed and accumulated than the inorganic form was. Se-enriched B. longum DD98 induced greater absorption of Se in plasma and accumulation of Se in several organs than the selenized yeast did, which could suggest the potential superior nutritional function of Se-DD98.

Topological insulators are materials that behave as insulators in the bulk and as conductors at the edge or surface due to the particular configuration of their bulk band dispersion. However, up to date possible practical applications of this band topology on materials' bulk properties have remained abstract. Here, we propose and experimentally demonstrate a topological bulk laser. We pattern semiconductor nanodisk arrays to form a photonic crystal cavity showing topological band inversion between its interior and cladding area. In-plane light waves are reflected at topological edges forming an effective cavity feedback for lasing. This band-inversion-induced reflection mechanism induces single-mode lasing with directional vertical emission. Our topological bulk laser works at room temperature and reaches the practical requirements in terms of cavity size, threshold, linewidth, side-mode suppression ratio and directionality for most practical applications according to Institute of Electrical and Electronics Engineers and other industry standards. We believe this bulk topological effect will have applications in near-field spectroscopy, solid-state lighting, free-space optical sensing and communication.

An efficient copper-catalyzed synthesis of pyrazolo[5,1-a]isoquinolines from 2-gem-dipyrazolylvinylbromobenzenes under mild conditions has been developed. The reaction occurred in moderate to good yields and tolerated nitrile, ether, and halogen substituted 2-gem-dipyrazolylvinylbromobenzenes.

We report on a topological bulk laser based on band-inversion-induced reflection constructed by trivial and topological photonic crystal arrays. It provides a novel lasing mode selection mechanism and renders high-performance laser devices. © 2020 The Author(s)

The Microfilm™ Test System is intended for quantitative microbiology and consists of three types of Microfilms for aerobic plate count (Microfilm APC), total coliform and Escherichia coli count (Microfilm TCEc), and yeast and mold count (Microfilm YMC). This study evaluated the performance of the Microfilm Test System against International Organization for Standardization (ISO) methods on 20 food matrixes and 2 environmental surfaces. Ruggedness, robustness, and stability were also determined, while inclusivity and exclusivity studies were performed on Microfilm TCEc and YMC. An independent laboratory evaluated the performance on four food matrixes and one environmental surface. No significant differences and high correlation coefficients were observed between the Microfilm Test System and the corresponding ISO methods (ISO 4833-1:2013 for APC, ISO 4832:2006 for total coliform count, ISO 16649-2: 2001 for E. coli, and ISO 21527 Part 1 and Part 2 for YMC) in spiked food matrixes and environmental samples. These results were corroborated by the independent laboratory. Inclusivity and exclusivity studies for Microfilm TCEc showed expected results for all the E. coli strains tested (blue-violet or violet color), while the related coliforms showed the expected blue-green colonies on the Microfilm. Similarly, all 100 fungal strains tested showed typical growth on Microfilm YMC. Exclusivity testing on Microfilm TCEc and YMC showed no growth of nontarget organisms. Robustness and ruggedness studies showed no significant differences in mean difference counts at varying incubation temperatures and times. Stability studies on three lots of the Microfilm Test System showed that it is stable at 2–25°C for 12 months and at 45°C for 6 weeks.

Armyworm feeding in large, destructive groups is hugely difficult to control and the oriental armyworm, Mythimna separata (Walk), is one such pest. In this study, we reported a semisynthetic artificial diet for the oriental armyworm. This diet is based on Ritter’s diet, a formula developed for Heliothis zea. The survival of M. separata was extremely low and only around 2% insects can reach the adult stage on Ritter’s diet. But, it can reach up to 100% if corn leaf powder (CLP) was mixed, and insects grew faster and gained more mass. After testing a set of mixtures of Ritter’s diet and CLP, we found that 14.3% was the optimal proportion of CLP for making the artificial diet. We then used chloroform to extract CLP. Insect performance was still much better on Ch-extracted CLP diets than that on Ritter’s diet, but it was poorer than that on the diets containing unprocessed CLP, suggesting that the essential factor(s) was only partially extracted from corn leaf. We then used methanol and dichloromethane, two solvents differing in their polarity, to process the extractions and analyzed the extracted chemicals using gas chromatography–mass spectrometry (GC-MS). Insects had a better performance on dichloromethane-extracted CLP diet in comparison to methanol-extracted one, indicating that the important factor(s) is more prone to methanol extraction. The reported recipe here is useful for the research on M. separata and possibly other grain-crop eating armyworms. The functions of the chemicals extracted from corn leaf tissue can be investigated in the future studies.

The eastern coastal zone of China is densely populated and widely recognized as a center of rice domestication, which has undergone dramatic sea-level fluctuation during the Holocene epoch. Hemudu culture is distributed mainly in the eastern coastal area and was once presumed as a mature agricultural economy based on rice, making it an ideal case for examining the remarkable human-environment interaction in the Lower Yangtze River. Though numerous studies have been conducted on the cultural evolution, ecological environment, and rice domestication of Hemudu culture, the impact of sea-level fluctuation on human settlement and food production remains controversial. In this study, we report high-resolution pollen, phytolith, and diatom records, and accurately measured elevation from the Yushan site, which is the closest site of Hemudu culture to the modern coastline. Based on the data gathered, we suggest that the Hemudu culture and subsequent Liangzhu culture developed in the context of regression and were interrupted by two transgressions that occurred during 6300-5600 BP and 5000-4500 BP. The regional ecological environment of the Yushan site alternated between intertidal mudflat and freshwater wetlands induced by sea-level fluctuations in the mid-late Holocene. Though rice was cultivated in the wetland as early as 6700 BP, this cultivation was subsequently discontinued due to the transgression; thus, full domestication of rice did not occur until 5600 BP in this region. Comprehensive analysis of multiple proxies in this study promote the understanding of the relationship between environmental evolution, cultural interruption, and rice domestication.

Coastal flooding catastrophes have affected human societies on coastal plains around the world on several occasions in the past, and are threatening 21st century societies under global warming and sea-level rise. However, the role of coastal flooding in the interruption of the Neolithic Liangzhu culture in the lower Yangtze valley, East China coast has been long contested. In this study, we used a well-dated Neolithic site (the Yushan site) close to the present coastline to demonstrate a marine drowning event at the terminal stage of the Liangzhu culture and discuss its linkage to relative sea-level rise. We analysed sedimentology, chronology, organic elemental composition, diatoms and dinoflagellate cysts for several typical profiles at the Yushan site. The field and sedimentary data provided clear evidence of a palaeo-typhoon event that overwhelmed the Yushan site at ∼2560 BCE, which heralded a period of marine inundation and ecological deterioration at the site. We also infer an acceleration in sea-level rise at 2560–2440 BCE from the sedimentary records at Yushan, which explains the widespread signatures of coastal flooding across the south Yangtze coastal plain at that time. The timing of this mid-Holocene coastal flooding coincided with the sudden disappearance of the advanced and widespread Liangzhu culture along the lower Yangtze valley. We infer that extreme events and flooding accompanying accelerated sea-level rise were major causes of vulnerability for prehistoric coastal societies.

Zonal wind stress plays an important role in the evolution of El Niño–Southern Oscillation (ENSO) events; however, a comprehensive comparison and analysis in terms of model performance and related bias in the interannual variability of zonal wind stress across the tropical Pacific has yet to be performed. In this study, the authors evaluate how well the individual atmospheric models participating in phase 5 of the Coupled Model Intercomparison Project simulate zonal wind stress. It is found that the wind stress anomalies simulated by the multi-model ensemble are weaker than those in the observation in both El Niño and La Niña events, with a larger bias in the former. Further analysis indicates that the bias associated with El Niño events may be mainly attributable to the weaker negative precipitation anomalies in the AMIP simulations, compared with observations, over the eastern Indian Ocean. Through the Gill-like responses in atmospheric circulation, the rainfall bias over the eastern Indian Ocean results in an easterly wind stress anomaly in the western and central equatorial Pacific, which to some extent offsets the westerly wind stress anomalies associated with El Niño events. Consequently, the responses of zonal wind stress anomalies to warm SST anomalies are much underestimated in AMIP simulations during El Niño events.

After more than 30 years of rapid urbanization, the overall urbanization rate of China reached 56.1% in 2015. However, despite China’s rapid increase in its overall rate of urbanization, clear regional differences can be observed. Furthermore, inadequate research has been devoted to in-depth exploration of the regional differences in China’s urbanization from a national perspective, as well as the internal factors that drive these differences. Using prefecture-level administrative units in China as the main research subject, this study illustrates the regional differences in urbanization by categorizing the divisions into four types based on their urbanization ratio and speed (high level: low speed; high level: high speed; low level: high speed; and low level: low speed). Next, we selected seven economic and geographic indicators and applied an ordered logit model to explore the driving factors of the regional differences in urbanization. A multiple linear regression model was then adopted to analyze the different impacts of these driving factors on regions with different urbanization types. The results showed that the regional differences in urbanization were significantly correlated to per capita GDP, industry location quotients, urban-rural income ratio, and time distance to major centers. In addition, with each type of urbanization, these factors were found to have a different driving effect. Specifically, the driving effect of per capita GDP and industry location quotients presented a marginally decreasing trend, while main road density appeared to have a more significant impact on cities with lower urbanization rates.

Urbanization has both direct and indirect impacts on land use change, and analyzing spatio-temporal characteristics of land use change is essential for understanding these impacts. By comparing Landsat TM images, this paper examines the changes of land use structure and landscape patterns in Shanghai from 1990 to 2015. It finds that the city doubled in size, with the growth of isolated construction land being most significant among eight land use types. A land use change matrix was established and landscape indices were selected to evaluate the change of spatial structure in Shanghai. In order to identify the main driving forces of city expansion in Shanghai, this research ran partial least square regression models to assess the impact of 10 social-economic factors on land use change of Shanghai from 1990 to 2015. It then conducted bivariate correlation analysis to explore the drivers of change of various land use types: urban settlement, rural settlement and isolated construction land. Besides quantitative analysis, this paper analyzes the influence of policy-dimensional factors in land use change. It concludes with future potential research topics on land use change in a rapidly urbanizing context.

The Sogatella furcifera (Horváth) is an important migrating rice pest whose outbreak may be caused by large-scale congregated landings. Hitherto, the meteorological factors that influence congregated landings were thought to be rainfall and downdraft. However, for migratory insects on a plateau, low temperature may be another key factor leading to congregated landings. However, no reports have been published. Therefore, this paper evaluates the reason for a large-scale congregated landing in the mountainous area in Yuanjiang via light trap monitoring. The meteorological backgrounds during light catch peaks were analyzed using the numeric simulation method. The results were as follows: 1) from May 7th to May 9th, 2012, the congregated landing of S. furcifera was caused by precipitation; 2) the congregated landing of S. furcifera on May 10th, 2012, was a result of low temperatures in the mountainous region. The driving airflow of S. furcifera climbed along the mountain terrain, which led to a decrease in temperature with the rise of the mountain terrain. Low temperature created physiological changes in S. furcifera, forcing S. furcifera to a lower flight altitude and eventually to a congregated landing; and 3) in the statistical analysis on 39 peak periods from 2010 to 2016 in the early spring, 20 peaks were caused by precipitation, and 19 peaks were caused by a low temperature barrier. Therefore, this study provided evidence of a plateau-migrating S. furcifera population congregated landing caused by low temperature.

The cyclic quenching with both the rapid heating and cooling was applied on 51CrV4 spring steels by a DIL805A/D dilatometer. The microstructures were observed by a scanning electron microscope (SEM) and a transmission electron microscope (TEM), whereas the strengthening mechanism of the test steels was discussed by the general equation of R p 0.2 i = σ 0 + Δ σ p i + Δ σ r i + Δ σ T i . The results demonstrated that the grain size was the lowest with only 1.76 µm, the area fraction of the twins was the highest up to 6.78% and the thickness of the twins was fined to 11.71 nm at six times. Also, an excellent comprehensive performance was obtained, such as the yield strength, the tensile strength and the area reduction of the test steels was increased substantially as the cyclic quenching was conducted from 1 to 6 times, where the maximum values were up to 1792.93 MPa, 2036.2 MPa and 44%, respectively. As a result, the strength increase was mainly attributed to the ultra-refine grain formation, the area fraction increase of the micro-nano scale twins and the size refinement decrease; whereas it was observed that the highest contribution to the strength and ductility was from the micro-nano scale twins.

The martensite multi-level microstructures of 20CrNi2Mo steel, which were quenched at the different temperatures of 900–1200 °C and tempered at 200 °C, were investigated by optical microscope (OM), scanning electron microscopy (SEM), electron backscattering diffraction (EBSD) and transmission electron microscopy (TEM), and the relationship between the microstructures and properties of strength and toughness was discussed by the classic formula of Hall–Petch. The results show that the size of prior austenite grain ( d r ), martensite packet ( d p ) and block ( d b ) increase with increasing of the quenching temperature, while the martensite lath ( d l ) size is opposite. On another hand, the confusion degree of the martensite packets changes from disorder to order. The boundaries of prior austenite grain, packet, block and the martensite lath are high angle boundaries (HBs) and low angle boundaries (LBs), respectively, and the ratio of the low angle boundaries increase with the quenching temperature by calculating to the multi-level microstructure size with the mathematical model established by myself. In addition, the relationship between the packet/block and strength follows the classical formula of Hall–Petch, and the size of d b is far lower than the size of d p , d b is the effective control unit of the strength. Meanwhile, d l is the effective control unit of toughness because it strongly impacts the crack initiation and propagation and follows also the Hall-Petch with toughness in 20CrNi2Mo steel.

Diapause is a complex physiological response that allows insects to survive unfavorable environmental conditions, and many signaling pathways participate in regulating this process. However, little is known about TOR signaling in the regulation of diapause. In this study, we found that the TOR pathway-related proteins TOR and Raptor are expressed at low levels in the brains of diapause-destined pupae of Helicoverpa armigera, consistent with a previous report that TOR signaling is associated with development. Interestingly, another TOR signaling-related protein, p-S6K, was increased in the brains of diapause-destined pupae. Our results showed that p-S6K in the brains of diapause-destined pupae can respond to the upstream signals reactive oxygen species (ROS) and AKT and that S6K activates the level of CREB, which binds to the HIF-1α promoter and increases its expression. Previous study has shown that HIF-1α levels elevated by ROS in the brains of diapause-destined pupae cause low mitochondrial activity for insect diapause. Thus, p-S6K in response to ROS/AKT regulates HIF-1α via activating transcription factor CREB for diapause initiation.

In this work, antibacterial activity of finger citron essential oil (FCEO, Citrus medica L. var. sarcodactylis) and its mechanism against food-borne bacteria were evaluated. A total of 28 components in the oil were identified by gas chromatography-mass spectrometry, in which limonene (45.36%), &gamma, terpinene (21.23%), and dodecanoic acid (7.52%) were three main components. For in vitro antibacterial tests, FCEO exhibited moderately antibacterial activity against common food-borne bacteria: Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Micrococcus luteus. It showed a better bactericidal effect on Gram-positive bacteria than Gram-negative. Mechanisms of the antibacterial action were investigated by observing changes of bacteria morphology according to scanning electron microscopy, time-kill analysis, and permeability of cell and membrane integrity. Morphology of tested bacteria was changed and damaged more seriously with increased concentration and exposure time of FCEO. FCEO showed a significant reduction effect on the growth rate of surviving bacteria and lead to lysis of the cell wall, intracellular ingredient leakage, and consequently, cell death.

The Schmidt reaction of ω-azido valeryl chlorides in the presence of an additional nucleophile was explored. The arenes, alcohols, and amines were demonstrated as the intermolecular trapping reagents for isocyanate ion and N-acyliminium ion from the Schmidt rearrangement, affording the corresponding products with moderate to excellent yields. Two 2-oxoindoles from the reaction were successfully converted into four natural alkaloids, namely, assoanine, anhydrolycorine, oxoassoanine, and anhydrolycorinone.

An effective approach composed of solution treatment, multipass cold rolling and aging was developed to improve the strength and ductility of novel Al-Cu-Mn alloys. This approach increased the yield strength by 214 MPa over that of the conventional peak-aged samples while maintaining a good elongation of 8.7%. The microstructure evolution was examined by confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). During postaging, deformed structures underwent a considerable decrease in dislocation density and typical dislocation network structures were formed. At the same time, highly dispersed nanoprecipitates and extensive ultrafine grains and nanograins were generated. These nanoprecipitations enabled effective dislocation pinning and accumulation during tension deformation. Therefore, composite nanostructures containing ultrafine grains, nanograins, dislocation network structures and nanoprecipitates were responsible for the simultaneous increases in strength and ductility. This paper provides a new understanding of designing composite nanostructure materials for achieving high strength and good ductility that is expected to be used for other age-hardenable alloys and steels.

Pointing mechanisms are widely used in aerospace fields. In order to make the pointing mechanism more adaptable and make the structure more compact and lightweight, a novel six degrees of freedom (6-DOF) parallel mechanism is proposed in this paper, which can provide wide range three-dimensional rotational movement and precise three-dimensional translational movement. Firstly, the description of the novel parallel mechanism is addressed and the equivalent motion to 3-RRR+3-CPR serial-parallel mechanism is demonstrated. Then, the kinematics are studied. Finally, using the performance atlas of motion/force transmission index, an optimal design of the structure parameters is conducted. Based on the kinematic simulation in ADAMS software, the kinematic analysis is verified correct. The novel mechanism has the advantages of wide rotation range, compact structure and decoupling of rotation and translation, which can be well applied in aerospace fields where both the pointing and position adjustment are necessary.

Understanding the paradoxical presence of extensive low-relief surfaces perched above deep valleys in SE Tibet is a long-standing challenge. Its origin, based on topographic analysis, has been explained traditionally by incision of a regional relict landscape or, more recently, by in situ formation in response to drainage area loss feedback. Here we apply a qualitative and quantitative source-to-sink approach to test whether either of the two mechanisms may apply by establishing potential links among detrital zircon provenance of the Oligocene–Miocene Pearl River Mouth Basin, drainage evolution of the Pearl River, and low-relief, high-elevation surface formation in the SE Tibetan Plateau margin. Our zircon record, combined with previous geochemical records from the northern South China Sea, confirms a significant Late Oligocene provenance shift, represented by an intensive addition of Proterozoic zircons and a gradual negative excursion in Nd isotopes. We interpret this provenance shift as a response to a progressive drainage expansion of the Pearl River, evolving from relatively small rivers confined to coastal South China in the Early Oligocene to a near-modern continental-scale drainage configuration in the Early Miocene, which may be correlated with an earlier surface uplift of SE Tibet than previously thought. This westward expansion process of the Pearl River favors the envisaged drainage evolution of the relict landscape model over that of the drainage area loss feedback model, suggesting that the Middle–Late Cenozoic low-relief, high-elevation surface formation in SE Tibet may be readily interpreted as preserving past tectonic and environmental conditions.

Background Diapause is the arrest of the development of insects and can be used for the development of effective agricultural pest management strategies. Heat shock protein 70 (Hsp70) is reported to be up-regulated during diapause to maintain survival in some insect species. However, its regulatory mechanism is unknown. Results Expression of hsp70 in Helicoverpa armigera was found to be up-regulated in diapause pupal brains. To elucidate the molecular regulatory mechanisms of hsp70, we focused our attention on its transcription factor, heat shock factor 1 (HSF1). Four alternative splicing variants of HSF1 from pupal brains of H. armigera were identified, and subcellular localization analysis indicated that these variants were exclusively expressed in the nucleus. Real-time PCR analysis showed that all of these variants were up-regulated in diapause pupal brains, and their expression patterns were consistent with that of hsp70. Finally, promoter activity assay and Western blotting detection demonstrated that hsp70 was activated and up-regulated by these variants. Conclusion Expression of hsp70 in H. armigera during diapause is regulated by multiple alternatively spliced isoforms of HSF1. The results of this study may provide important information for understanding the regulatory mechanisms of hsps during insect diapause. © 2018 Society of Chemical Industry.

The plate kinematic history of the South China Sea opening is key to reconstructing how the Mesozoic configuration of Panthalassa and Tethyan subduction systems evolved into today's complex Southeast Asian tectonic collage. The South China Sea is currently flanked by the Palawan Continental Terrane in the south and South China in the north and the two blocks have long been assumed to be conjugate margins. However, the paleogeographic history of the Palawan Continental Terrane remains an issue of uncertainty and controversy, especially regarding the questions of where and when it was separated from South China. Here we employ detrital zircon U–Pb geochronology and heavy mineral analysis on Cretaceous and Eocene strata from the northern South China Sea and Palawan to constrain the Late Mesozoic–Early Cenozoic provenance and paleogeographic evolution of the region testing possible connection between the Palawan Continental Terrane and the northern South China Sea margin. In addition to a revision of the regional stratigraphic framework using the youngest zircon U–Pb ages, these analyses show that while the Upper Cretaceous strata from the Palawan Continental Terrane are characterized by a dominance of zircon with crystallization ages clustering around the Cretaceous, the Eocene strata feature a large range of zircon ages and a new mineral group of rutile, anatase, and monazite. On the one hand, this change of sediment compositions seems to exclude the possibility of a latest Cretaceous drift of the Palawan Continental Terrane in response to the Proto-South China Sea opening as previously inferred. On the other hand, the zircon age signatures of the Cretaceous–Eocene strata from the Palawan Continental Terrane are largely comparable to those of contemporary samples from the northeastern South China Sea region, suggesting a possible conjugate relationship between the Palawan Continental Terrane and the eastern Pearl River Mouth Basin. Thus, the Palawan Continental Terrane is interpreted to have been attached to the South China margin from the Cretaceous until the Oligocene oceanization of the South China Sea. In our preferred paleogeographic scenario, the sediment provenance in the northeastern South China Sea region changed from dominantly nearby Cretaceous continental arcs of the South China margin to more distal southeastern South China in the Eocene.

Gluten derived from wheat and related Triticeae can induce gluten sensitivity as well as celiac disease. Consequently, gluten content in foods labeled "gluten-free" is regulated. Determination of potential contamination in such foods is achieved using immunoassays based on monoclonal antibodies (mAbs) that recognize specific epitopes present in gluten. However, food-processing measures can affect epitope recognition. In particular, preparation of wheat protein isolate through deamidation of glutamine residues significantly limits the ability of commercial gluten testing kits in their ability to recognize gluten. Adding to this concern, evidence suggests that deamidated gluten imparts more pathogenic potential in celiac disease than native gluten. To address the heightened need for antibody-based tools that can recognize deamidated gluten, we have generated a novel mAb, 2B9, and subsequently developed it as a rapid lateral flow immunoassay. Herein, we report the ability of the 2B9-based lateral flow device (LFD) to detect gluten from wheat, barley, and rye and deamidated gluten down to 2 ppm in food as well as its performance in food testing.

Allergies to cow's milk are very common and can present as life-threatening anaphylaxis. Consequently, food labeling legislation mandates that foods containing milk residues, including casein and/or β-lactoglobulin, provide an indication of such on the product label. Because contamination with either component independent of the other can occur during food manufacturing, effective allergen management measures for containment of milk residues necessitates the use of dual screening methods. To assist the food industry in improving food safety practices, we have developed a rapid lateral flow immunoassay test kit that reliably reports both residues down to 0.01 μg per swab and 0.1 ppm of protein for foods. The assay utilizes both sandwich and competitive format test lines and is specific for bovine milk residues. Selectivity testing using a panel of matrices with potentially interfering substances, including commonly used sanitizing agents, indicated reduction in the limit of detection by one-to fourfold. With food, residues were easily detected in all cow's milk-based foods tested, but goat and sheep milk residues were not detected. Specificity analysis revealed no cross-reactivity with common commodities, with the exception of kidney beans when present at high concentrations (1%). The development of a highly sensitive and rapid test method capable of detecting trace amounts of casein and/or β-lactoglobulin should aid food manufacturers and regulatory agencies in monitoring for milk allergens in environmental and food samples.

In this paper, the effect of substructure of lath martensite on the mechanical properties was discussed in detail. Results indicated that prior austenite grain, packet and block increase with the increasing of quenching temperature. A good linear relationship exists between the packet, block and prior austenite, which reveal that the size of packet, block depends on prior austenite grain. However, lath is increased with not determined by prior austenite grain. Based on the EBSD analysis, the large ratio of the low angle orientation boundaries determines the better plasticity is obtained in coarse grain. Therefore, the refining of martensite lath or the increase of the low angle orientation plays an important role on improving the plasticity in lath martensite steel.

In this work, the formation of micro-voids for ductile fracture has been discussed with regards to the classical nucleation theory from the phase transformation in 20CrNi2Mo steel. The differences in them were determined based upon the driving force and the resistance. In terms of tensile load, the driving force was the energy of tensile load before necking, while the resistance was the surface energy from the formation of mass of micro-voids, as determined by the fracture toughness instead of the phase transformation. Finally, the relationship between the formation of micro-voids and the macroscopic properties was discussed. The results illustrated that the formation of micro-voids depended on the elastic-plastic energy and on the yield strength represented by r* (the critical formation radius) and (the critical formation energy). These results were confirmed from r 1* (with the experiment) and r 2* (with the calculation). The work provided a novel way to study the relationship of micro-parameters and macro-properties. In addition, it was found that the critical formation diameter (2r*) of micro-voids was close to the width of martensite lath (d l).