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Objective To explore the expression and localization of brain derived neurotrophic factor(BDNF) in neurons and astrocytes(AS) of transgenic mice with amyotrophic lateral sclerosis(ALS), and to further clarify the pathogenesis of ALS. Methods Immunofluorescence assay was used to detect the expression of BDNF in spinal cord neurons and astrocytes of 95, 108 and 122 days old ALS transgenic mice. The wild type(WT) mice were used as controls group. Neuron cell line NSC34 was used as a cell model to establish wild type and SOD1-G93A mutant NSC34 cell strains, the transgenic mice from the same litter were selected to culture the primary astrocytes. The protein expression of BDNF in NSC34 cell model and primary astrocytes was detected by Western blot. Results Compared with WT mice, the expression of BDNF in neurons was decreased in spinal cord tissues of 95, 108 and 122 days old ALS transgenic mice(P＜0.05), while the expression of BDNF/GFAP double positive cells was significantly increased.In the cell model, BDNF expression decreased in SOD1-G93A mutant NSC34 cells(P＜0.05) and increased in activated astrocytes(P＜0.05). Conclusions The expression and localization of BDNF in neurons and activated astrocytes of transgenic mice with ALS suggest that the autonomic mechanism of neurons and the non-autonomic mechanism mediated by astrocytes play an important role in the pathogenesis of ALS.

Intermolecular carbophosphination reaction of alkynes or alkenes with unreactive C−P bonds remains an elusive challenge. Herein, we used a Ni−Al bimetallic catalyst to realize an intermolecular carbophosphination reaction of alkynes with 5‐membered phosphole oxides, providing a series of 7‐membered phosphepines in up to 94 % yield. [ABSTRACT FROM AUTHOR]

Enantioselective Ni‐catalyzed C(sp3)−H bond activation remains an elusive challenge. Herein, we used phosphine oxide‐ligated Ni−Al bimetallic catalyst to realize enantioselective Ni‐catalyzed aliphatic C(sp3)−H activation of formamides, providing a series of chiral N‐containing heterocycles in 40–95 % yield and 70–95 % ee. [ABSTRACT FROM AUTHOR]

Presents a study that examined neodymium-dysprosium-iron-cobalt-titanium (Ti) magneto-optical material. Goal of the study; Preparation of the alloy targets; Effect of the addition of Ti on the target.

Background: The extent to which co-evolutionary processes shape morphological traits is one of the most fascinating topics in evolutionary biology. Both passive and active pollination modes coexist in the fig tree (Ficus, Moraceae) and fig wasp (Agaonidae, Hymenoptera) mutualism. This classic obligate relationship that is about 75 million years old provides an ideal system to consider the role of pollination mode shifts on pollen evolution. Methods and Main Findings: Twenty-five fig species, which cover all six Ficus subgenera, and are native to the Xishuangbanna region of southwest China, were used to investigate pollen morphology with scanning electron microscope (SEM). Pollination mode was identified by the Anther/Ovule ratio in each species. Phylogenetic free regression and a correlated evolution test between binary traits were conducted based on a strong phylogenetic tree. Seventeen of the 25 fig species were actively pollinated and eight species were passively pollinated. Three pollen shape types and three kinds of exine ornamentation were recognized among these species. Pollen grains with ellipsoid shape and rugulate ornamentation were dominant. Ellipsoid pollen occurred in all 17 species of actively pollinated figs, while for the passively pollinated species, two obtuse end shapes were identified: cylinder and sphere shapes were identified in six of the eight species. All passively pollinated figs presented rugulate ornamentation, while for actively pollinated species, the smoother types - psilate and granulate-rugulate ornamentations - accounted for just five and two among the 17 species, respectively. The relationship between pollen shape and pollination mode was shown by both the phylogenetic free regression and the correlated evolution tests. Conclusions: Three pollen shape and ornamentation types were found in Ficus, which show characteristics related to passive or active pollination mode. Thus, the pollen shape is very likely shaped by pollination mode in this unique obligate mutualism. [ABSTRACT FROM AUTHOR]

Summary [ABSTRACT FROM AUTHOR]

Through the behavioral observation of Ficus curtipes fig wasps and the counting of various kinds of flowerets in F. curtipes figs, the oviposition timing and community structure of 12 F. curtipes fig wasp species were studied. Besides the agaonid wasp Eupristina sp., the two non-agaonid wasps Diaziella yangi and Lipothymus sp. could enter into F. curtipes figs and oviposit. The other nine non-agaonid fig wasps ( Walkerella sp., Micranisa sp., Sycophilomorpha sp., Philotrypesis sp., Sycosapter sp., Sycobia sp., Ficomila sp., Ormyrus sp. and Sycophila sp.) oviposited outside the figs. In the fig wasp community, Eupristina sp. was the dominant species, accounting for 62.11% of the total, D. yangi and Lipothymus sp. accounted for 27.19% and 4.71%, respectively, while the other nine non-agaonid fig wasp species only occupied 5.99%. The non-agaonid fig wasps produced their progeny through the reproduction strategies of oviposition timing and diet allocation of female flowerets, so as to sustain the fig-wasp mutualism. The individuals of non-agaonid fig wasp progeny had significant negative correlation with those of agaonid fig wasp progeny, but no correlation with F. curtipes seed production. [ABSTRACT FROM AUTHOR]

Competing Interests: The authors have no conflicts of interest to declare.

Enantioselective Ni-catalyzed C(sp 3 )-H bond activation remains an elusive challenge. Herein, we used phosphine oxide-ligated Ni-Al bimetallic catalyst to realize enantioselective Ni-catalyzed aliphatic C(sp 3 )-H activation of formamides, providing a series of chiral N-containing heterocycles in 40-95 % yield and 70-95 % ee., (© 2022 Wiley-VCH GmbH.)

Variation in resistance of xylem to embolism among flowers, leaves, and stems strongly influences the survival and reproduction of plants. However, little is known about the vulnerability to xylem embolism under drought stress and their relationships to the anatomical traits of pits among reproductive and vegetative organs. In this study, we investigated the variation in xylem vulnerability to embolism in peduncles, petioles, and stems in a woody plant, Magnolia grandiflora . We analyzed the relationships between water potentials that induced 50% embolism (P 50 ) in peduncles, petioles, and stems and the conduit pit traits hypothesized to influence cavitation resistance. We found that peduncles were more vulnerable to cavitation than petioles and stems, supporting the hypothesis of hydraulic vulnerability segmentation that leaves and stems are prioritized over flowers during drought stress. Moreover, P 50 was significantly correlated with variation in the dimensions of inter-vessel pit apertures among peduncles, petioles and stems. These findings highlight that measuring xylem vulnerability to embolism in reproductive organs is essential for understanding the effect of drought on plant reproductive success and mortality under drought stress., Competing Interests: The authors declare no conflict of interest., (© 2020 Kunming Institute of Botany, Chinese Academy of Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.)