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Nominally anhydrous minerals (NAMs) composing Earth's and planetary rocks incorporate microscopic amounts of volatiles. However, volatile distribution in NAMs and their effect on physical properties of rocks remain controversial. Thus, constraining trace volatile concentrations in NAMs is tantamount to our understanding of the evolution of rocky planets and planetesimals. Here, we present an approach of trace-element quantification using micro-scale Nuclear Magnetic Resonance (NMR) spectroscopy. This approach employs the principle of enhanced mass-sensitivity in NMR microcoils. We were able to demonstrate that this method is in excellent agreement with standard methods across their respective detection capabilities. We show that by simultaneous detection of internal reference nuclei, the quantification sensitivity can be substantially increased, leading to quantifiable trace volatile element amounts of about 50 ng/g measured in a micro-meter sized single anorthitic mineral grain, greatly enhancing detection capabilities of volatiles in geologically important systems. Nominally anhydrous minerals composing Earth's and planetary rocks incorporate microscopic amounts of volatiles whose distribution affects their physical properties. Here the authors present an approach for trace-element quantification using micro-scale Nuclear Magnetic Resonance spectroscopy. [ABSTRACT FROM AUTHOR]

The dead zone in ultrasonic time-of-flight diffraction (TOFD) restricts the quantitation of near-surface defects. Alternative TOFD techniques introduce other tip-diffracted/scattered waves with longer propagation times to implement defect detection, but the applicability is influenced due to ignoring the change of acoustic path of the diffracted shear wave in wedge. In this paper, the mode-converted wave (MCW) method is exemplified to analyze the propagation path of diffracted shear wave and the change of the received point in wedge. On this basis, the corrected MCW method is proposed by establishing the relationship between the propagation time of MCW and defect depth according to Fermat's principle. The simulation and experiments show that the depth of near-surface dead zone is reduced by 60% with the corrected MCW method. The positioning errors of the defects in the aluminum alloy sample with a thickness of 20.0 mm are no more than 0.15 mm by using the TOFD probes with 10 MHz center frequency and 40 mm probe center spacing (PCS) and the 60° wedges. Compared to the conventional MCW method, the corrected method widens the range of applicable TOFD signals in B-scan images and reduces the measurement errors of defect depths to within 3.5% under ideal conditions. [ABSTRACT FROM AUTHOR]

Tibetan Cenozoic syn-collisional potassic–ultrapotassic igneous rocks provide unique insights into the processes and origins of metasomatism in the upper mantle, as well as continental subduction and plateau uplift. Crustal recycling in the magma source of the Tibetan potassic–ultrapotassic rocks has been well-documented. However, the nature of the metasomatic agents and the timing of mantle metasomatism are still disputed. Oxygen isotopes are a powerful tracer for identifying any recycled crustal material in the mantle due to the significant fractionation caused by surface water–rock interaction. Here we present an integrated in-situ study of oxygen isotopes and the major/trace elements of olivine in the Cenozoic potassic–ultrapotassic rocks and mantle xenoliths from the western Kunlun area of the northwestern Tibet. Olivines from mantle xenoliths have oxygen isotope compositions that range from elevated δ18O values (5.83 ± 0.78–5.97 ± 0.40‰) to values (5.09 ± 0.56–5.10 ± 0.46‰) that are indistinguishable from typical mantle olivine values of 5.18 ± 0.28‰ (Mattey et al., Earth Planet Sci Lett 128:231–241, 1994). Elevated olivine δ18O values reflect mantle metasomatic processes by an 18O-rich agent, although a few olivine rims show higher δ18O values caused by reactions with host lavas. In contrast, olivine oxygen isotope compositions of potassic–ultrapotassic rocks are higher than typical "mantle" values and those of the mantle xenoliths (6.51 ± 0.74–7.52 ± 0.24‰). There is no sign of crustal contamination, and fractional crystallization did not change the isotopic compositions of the studied potassic–ultrapotassic igneous rocks, thus their high-δ18O signature reflects the nature of the primary melts and their source region. Enrichments in olivine 18O and clinopyroxene Sr isotopic compositions, as well as the enriched trace element compositions of clinopyroxene and orthopyroxene in the mantle xenoliths, indicate that they have been highly metasomatized by silicate materials with a minor carbonate component from recycled Indian continental crustal component, and the enriched lithospheric mantle is the magma source of potassic–ultrapotassic rocks. High olivine δ18O values are a common feature of Tibetan Cenozoic potassic–ultrapotassic rocks, consistent with the mantle metasomatic agents that were derived directly from recycled continental crust material via Indian continental subduction. Our study reinforces the profound link between continental subduction, mantle processes and generation of Tibetan Cenozoic potassic–ultrapotassic rocks. [ABSTRACT FROM AUTHOR]

Zircon is probably the most important mineral used in the dating formation of high-pressure (HP) and ultrahigh-pressure (UHP) metamorphic rocks. The origin of zircon, i.e., magmatic or metamorphic, is commonly assessed by its external morphology, internal structure, mineral inclusions, Th/U ratios and trace element composition. In this study, we present an unusual case of metamorphic zircon from the Qiangtang eclogite, north-central Tibet. The zircon grains contain numerous eclogite-facies mineral inclusions, including omphacite, phengite, garnet and rutile; hence, they are clearly of metamorphic origin. However, they display features similar to common magmatic zircon, including euhedral crystal habit, high Th/U ratios and enriched heavy rare earth elements pattern. We suggest that these zircon grains formed from a different reservoir from that for garnet where no trace elements was present and trace element equilibrium between zircon and garnet was achieved. U-Pb dating of zircon gave an age of 232-237 Ma for the eclogite, and that of rutile yielded a slightly younger age of ca. 217 Ma. These ages are consistent with the reported Lu-Hf mineral isochron and phengite Ar-Ar ages. The zircon U-Pb and mineral Lu-Hf isochron ages are interpreted as the time of the peak eclogite-facies metamorphism, whereas the rutile U-Pb and phengite Ar-Ar ages represent the time of exhumation to the middle crust. Thus, the distinction between metamorphic and magmatic zircons cannot be made using only Th/U ratios and heavy REE compositions for HP-UHP metamorphic rocks of oceanic derivation. [ABSTRACT FROM AUTHOR]

Well-characterized matrix-matched natural mineral references of known age are an important prerequisite for SIMS (secondary ion mass spectrometry) U-Th-Pb dating. We have characterized RW-1, a 44 g yellowish-brown single monazite specimen from a Norwegian pegmatite as an excellent hi-Th reference material for secondary ion mass spectrometric U-Th-Pb dating. A total of 206 secondary ion mass spectrometric analyses over six analytical sessions were performed on different monazite fragments of RW-1. The analyses resulted in Pb-based common lead corrected Pb/U ages and Th-Pb ages with overall 2 % (2 SD = standard deviation) variations, indicating the good U-Th-Pb system homogeneity. The homogeneity of Th content of 11.8 ± 1.0 wt% (2 SD) and Th/U of 42 ± 3 (2 SD) make this crystal also a good compositional reference material. We used the combined ID-TIMS(Pb)/ID-MC-ICP-MS(U) technique (i.e. isotope dilution thermal ionization mass spectrometry for Pb, and isotope dilution multi-collector inductively-coupled plasma mass spectrometry for U) to determine U-Pb ages of the monazite samples studied. The mean Pb/U age of 904.15 ± 0.26 Ma (95 % confidence level) is recommended as the best estimate crystallization age for RW-1 monazite. Considering that the most commonly distributed U-Pb monazite reference materials have rather low ThO, we suggest that this RW-1 monazite with its ThO of 13.5 wt% is a suitable reference material providing investigators more confidence when dating high-Th monazite unknowns. [ABSTRACT FROM AUTHOR]

Key message: This research reveals the different expression patterns of anthocyanin biosynthesis enzyme genes and transcription factors in six red-skinned pear cultivars with different genetic backgrounds. Abstract: Skin color is an important feature of pear fruits, with red skin generally attracting consumers. However, great differences of coloration exist in different pear cultivars. To elucidate the characteristics of pigmentation in pear cultivars with different genetic backgrounds, six cultivars, belonging to P. communis, P. pyrifolia, P. ussuriensis, P. bretschneideri, and a hybrid of P. communis × P. pyrifolia, were used to detect pigment concentrations, expressions of seven anthocyanin biosynthesis enzyme genes, and three related transcription factor genes. Results showed that the occidental pears 'Starkrimson' and 'Red Bartlett' colored at the beginning of fruit setting, but color decreased with fruit maturity; the other four cultivars showed low anthocyanin accumulations and the contents increased during fruit development, but also decreased at later stages. The expression patterns of genes encoding enzymes indicated that ANS and UFGT were decisive genes for anthocyanin biosynthesis for red-skinned pear, and their different expressions led to the coloration differences between occidental and oriental pears. The expression patterns of transcription factors indicated that the different co-expression of MYB10 and bHLH33 genes and the different expressions of WD40 are involved in the differential regulation mechanisms of anthocyanin biosynthesis and coloration pattern between occidental and oriental pears. [ABSTRACT FROM AUTHOR]

Large conductance calcium-activated potassium channels (Slo) play important roles in controlling neuronal excitability. At present, very little is known about the function of Slo channels on ovarian development. We cloned the SPSlo gene from the mud crab, Scylla paramamosain. This gene shows 91 and 93 % sequence identity to PISlo from the spiny lobster, Panulirus interruptus and CBSlo from the jonah crab, Cancer borealis, respectively. We isolated six variants of the SPSlo cDNA within S. paramamosain ovary tissue. Sequence analysis indicated that there were at least seven alternative sites in SPSlo, each with multiple alternative segments. Real-time PCR showed that the SPSlo gene was expressed in various tissues, and highly expressed in brain and ovary. In addition, the expression of SPSlo changed throughout ovarian development, highest at the early-developing stage (Stage II) followed by a slow decrease in subsequent stages. These results suggested that SPSlo channels may be implicated in the ovarian development of the mud crab. [ABSTRACT FROM AUTHOR]

To reveal the molecular mechanisms that led to the red/green color mutation of pear between the cultivar 'Early red Doyenne du Comice' and its green variant strain, the full-length cDNA of the seven anthocyanin biosynthesis genes ( PAL, CHS, CHI, DFR, F3H, ANS, UFGT) was cloned in both cultivars. The accession number has been submitted to National Center for Biotechnology Information (NCBI) as KC460392, KC460393, KC460394, KC460395, KC460396, KC460397, and KC460398, respectively. However, there was no sequence difference between the color mutants, which means that the skin color change was not caused by mutation of any of these genes. Meanwhile, the expression levels of these seven genes were examined by quantitative real-time PCR (qRT-PCR). Results showed that most of the structural genes were up-regulated in the red-skinned cultivar during fruit development, but the CHI and UFGT genes were highly expressed only at an early stage. The expression levels of the transcription factors MYB10, bHLH, and WD40 were also investigated by qRT-PCR, and the MYB10 gene was found to be expressed at significantly higher levels in the red variety than in the green mutant at the early stage, while the expression levels of bHLH and WD40 were higher at a later stage. These data indicate that the expression difference of structural genes in the anthocyanin biosynthesis pathway led to the skin color change of the mutant. However, MYB10, bHLH, and WD40 do not appear to be the key transcription factors that regulate the biosynthesis of anthocyanin and determine the red/green color mutant. [ABSTRACT FROM AUTHOR]

Fruit skin color is an important parameter of outer quality and plays an important role in attracting customers. In many plants, it is the result of coordinative regulation of anthocyanin pathway genes. In our study, the differential expression of cDNA library in a pair of pear mutant with red and green color was investigated to find candidate genes which might regulate the anthocyanin biosynthesis and control the coloration of pear. We constructed a cDNA library using the cDNA-amplified fragment length polymorphism approach to analyze the transcriptional differences between the original cultivar 'Early red Doyenne du Comice' with high anthocyanin content in the peel and its green color mutant with comparatively low anthocyanin content. Altogether, 47 transcript-derived fragments, putatively involved in anthocyanin biosynthesis, primary metabolism, stress, and defense responses, were identified. The relationships of differentially expressed genes and coloration were investigated by quantitative real-time PCR with fruit skin samples at different developmental stages. A gene putatively involved in anthocyanin biosynthesis was found and named as PyMADS18. Its sequence is similar to genes reported in the literature as regulators of anthocyanin biosynthesis. The expression results indicate that PyMADS18 is likely to be involved in anthocyanin accumulation and regulation of anthocyanin synthesis in early fruit development of pear. [ABSTRACT FROM AUTHOR]

This study identified eight S-haplotype-specific F-box genes ( SFB alleles) and one S-haplotype-specific F-box-like gene ( SFB-like gene) from genomic DNA by PCR combined with cleaved amplified polymorphic sequence markers in Prunus pseudocerasus and Prunus speciosa. The unknown sequences of C-termini were obtained by thermal asymmetric interlaced PCR. The whole nucleotide sequences of these genes were submitted to the EMBL/GenBank database. The SFBs shared typical structural features with SFBs from other Prunus species exhibiting gametophytic self-incompatibility. The deduced amino acid identity ranged from 77.1% to 82.4% among the four PpsSFBs and from 70.4% to 80.2% among the four PspeSFBs. The typical structural features were also detected in the PpsFB, but the sequence polymorphism was lower. The nucleotide identities ranged from 71.3% to 90.3% among the eight introns of the SFBs, the length of these introns varied from 95 to 121 bp and showed few polymorphisms. The distance between these SFBs and the corresponding S-RNases (S-ribonucleases) varied from 33 to 956 bp. Moreover, sequence analysis showed that interspecific amino acid identities in comparison with some other Prunus species were often higher than intraspecific identities, similar to S-RNase alleles. In addition, a similarity comparison found that the deduced amino acid identities among SFB alleles were higher than among S-RNase alleles, and the similarity data showed that the relationships among SFB alleles differed among S-RNase alleles, suggesting that the S-RNase and SFB alleles were separated but correlated during the coevolutionary process. [ABSTRACT FROM AUTHOR]

Lithium garnets have been widely studied as promising electrolytes that could enable the next-generation all-solid-state lithium batteries. However, upon exposure to atmospheric moisture and carbon dioxide, insulating lithium carbonate forms on the surface and deteriorates the interfaces within electrodes. Here, we report a scalable solid sintering method, defined by lithium donor reaction that allows for complete decarbonation of Li6.4La3Zr1.4Ta0.6O12 (LLZTO) and yields an active LiCoO2 layer for each garnet particle. The obtained LiCoO2 coated garnets composite is stable against air without any Li2CO3. Once working in a solid-state lithium battery, the LiCoO2-LLZTO@LiCoO2 composite cathode maintains 81% of the initial capacity after 180 cycles at 0.1 C. Eliminating CO2 evolution above 4.0 V is confirmed experimentally after transforming Li2CO3 into LiCoO2. These results indicate that Li2CO3 is no longer an obstacle, but a trigger of the intimate solid-solid interface. This strategy has been extended to develop a series of LLZTO@active layer materials. Formation of insulating lithium carbonate on surface of lithium garnets hinders their application as solid electrolyte in lithium ion batteries. Here the authors explore a scalable sintering approach to utilize the undesired Li2CO3 and improve the active material-electrolyte interface within cathodes. [ABSTRACT FROM AUTHOR]

Autophagy-induced cancer cell death has become a novel strategy for the development of cancer therapeutic drugs. Numerous studies have indicated that green tea polyphenols induce both autophagy and apoptosis in a variety of cancer cells. Here, we synthesized a series of green tea polyphenol analogues, among which JP8 was shown to potently activate autophagy. JP8 treatment had a stronger effect on apoptosis in B16-F10 melanoma cells than that in normal AML-12 hepatocytes. JP8 selectively resulted in reactive oxygen species (ROS) accumulation in B16-F10 cells, and this effect was associated with corresponding increases in key components of the ER stress-mediated apoptosis pathway. Pharmacological inhibition of ROS by N-acetyl-L-cysteine (NAC) attenuated JP8-induced autophagy and apoptosis, indicating an upstream role of ROS in JP8-induced autophagy. An in vivo study showed that JP8 had significant antitumor effects in a B16-F10 xenograft mouse model. Our results indicate that JP8 is a novel anticancer candidate with both autophagy and ROS induction activities. [ABSTRACT FROM AUTHOR]