Bis(2-methyl­piperidinium) penta­chlorido­anti­monate(III)

The asymmetric unit of the title compound, (C6H14N)2[SbCl5], contains one cation and half of the anion on a special position (specifically, the SbIII ion and three chloride anions are situated on a mirror plane). In the [SbCl5]2− unit, the SbIII ion is coordinated by five chloride anions [Sb—Cl = 2.3721 (11)–2.6656 (12) Å] in a distorted square-pyramidal geometry. However, one chloride anion from a neighbouring [SbCl5]2− unit provides a short Sb⋯Cl contact of 3.3600 (12) Å and completes the Sb coordination environment up to an elongated octa­hedron. In the crystal, N—H⋯Cl hydrogen bonds link cations and anions into columns propagating along [100]

Quercetin attenuates lipopolysaccharide-induced myocardial cell apoptosis via modulation of cAMP-Epac pathway

Purpose: To investigate the effects and mechanism of action of quercetin (QUE) on sepsis-induced apoptosis of myocardial cells in vitro. Methods: Lipopolysaccharide (LPS) was used to induce apoptosis H9c2 myocardial cells. Apoptosis of H9c2 cells was determined by propidium iodide staining. Knock down of Epac1 was achieved using small interfering RNA (SiEpac1). The levels of associated proteins (Epac1 and Rap1) were evaluated by western blotting. Results: Lipopolysaccharide promoted apoptosis of H9c2 cells and inhibited the activity of cAMP-Epac pathway (p < 0.001 vs. control). Quercetin inhibited caspase 3 activity and apoptosis (p < 0.05 vs. LPS) induced by LPS via activation of cAMP-Epac1 signaling pathway. Moreover, Epac1 knockdown decreased the anti-apoptosis effect of Que, which indicates that Que attenuated apoptosis partly via cAMP-Epac pathway. Conclusion: Que attenuated LPS-induced apoptosis in myocardial cells via activation of cAMP-Epac1 pathway. Therefore, quercetin treatment may serve as a promising strategy in the treatment of sepsisinduced myocardial injury

Tris(2-methyl­piperidinium) tetra­chlorido­ferrate dichloride

The asymmetric unit of the title salt, (C6H14N)3[FeCl4]Cl2, consists of a tetra­hedral tetra­chloro­ferrate anion, three independent 2-methyl­piperidinium cations and two chloride ions. All the piperidine rings adopt chair conformations. In the crystal, the organic cations and the free chloride anions are linked into chains parallel to the a axis by N—H⋯Cl hydrogen bonds

All-polarization-maintaining linear cavity fiber lasers mode-locked by nonlinear polarization evolution in stretched pulse regime

Nonlinear polarization evolution (NPE) is among the most advanced techniques for obtaining ultrashort pulses with excellent optical performance. However, it is challenging to design environmentally stable NPE fiber oscillators using only polarization-maintaining (PM) fibers. Here, we use the same PM fiber and non-reciprocal phase shifter to design two different devices, which are capable of acting as effective NPE saturable absorbers (SAs) in two all-PM linear cavity fiber lasers. These two laser setups differ in the position of the non-reciprocal phase shifter, the presence of which is crucial for the proposed fiber lasers to reduce their mode-locking thresholds and achieve high repetition rates above 100 MHz. The mode-locking principle and pulse evolution in the laser cavity are investigated theoretically. The first all-PM fiber oscillator emits sub-200 fs stretched pulses with low peak powers. The second oscillator, with a simpler architecture, directly delivers stretched pulses with high peak powers, the spectral bandwidth greater than 30 nm, and the pulse duration less than 90 fs. To the best of our knowledge, 79 fs achieved in this design is the shortest pulse duration provided by PM fiber lasers using NPE mode-lockers.Comment: to be published in J. Lightwave Tec

Delineating the key virulence factors and intraspecies divergence of Vibrio harveyi via whole-genome sequencing

Vibrio harveyi is one of the major pathogens in aquaculture. To identify the key virulence factors affecting pathogenesis of V. harveyi towards fish, we conducted a field investigation for three representative fish farms infected with V. harveyi. Multilocus sequence typing (MLST) and whole-genome sequencing were conducted to delineate the phylogenetic relationship and genetic divergence of V. harveyi. A total of 25 V. harveyi strains were isolated from the diseased fish and groundwater and were subtyped into 12 sequence types by MLST. Five virulence genes, mshB, pilA, hutR, ureB, and ureG, were variably presented in the sequenced strains. The virulence gene profiles strongly correlated with the distinct pathogenicity of V. harveyi strains, with a strain harboring all five genes exhibiting the highest virulence towards fish. Phenotype assay confirmed that reduced virulence correlated with decreased motility and biofilm formation ability. Additionally, three types of type VI secretion system, namely T6SS1, T6SS2, and T6SS3, were identified in V. harveyi strains, which can be classified into six, four, and 12 subtypes, respectively. In conclusion, the results indicated that the virulence level of V. harveyi is mainly determined by the above virulence genes, which may play vital roles in environmental adaptation for V. harveyi

Losses Can Be Blessings: Routing Self-Supervised Speech Representations Towards Efficient Multilingual and Multitask Speech Processing

Self-supervised learning (SSL) for rich speech representations has achieved empirical success in low-resource Automatic Speech Recognition (ASR) and other speech processing tasks, which can mitigate the necessity of a large amount of transcribed speech and thus has driven a growing demand for on-device ASR and other speech processing. However, advanced speech SSL models have become increasingly large, which contradicts the limited on-device resources. This gap could be more severe in multilingual/multitask scenarios requiring simultaneously recognizing multiple languages or executing multiple speech processing tasks. Additionally, strongly overparameterized speech SSL models tend to suffer from overfitting when being finetuned on low-resource speech corpus. This work aims to enhance the practical usage of speech SSL models towards a win-win in both enhanced efficiency and alleviated overfitting via our proposed S$^3$-Router framework, which for the first time discovers that simply discarding no more than 10\% of model weights via only finetuning model connections of speech SSL models can achieve better accuracy over standard weight finetuning on downstream speech processing tasks. More importantly, S$^3$-Router can serve as an all-in-one technique to enable (1) a new finetuning scheme, (2) an efficient multilingual/multitask solution, (3) a state-of-the-art ASR pruning technique, and (4) a new tool to quantitatively analyze the learned speech representation. We believe S$^3$-Router has provided a new perspective for practical deployment of speech SSL models. Our codes are available at: https://github.com/GATECH-EIC/S3-Router.Comment: Accepted at NeurIPS 202

4-Bromo-3-methyl­anilinium perchlorate 18-crown-6 clathrate

The reaction of 4-bromo-3-methyl­anilinium perchlorate and 18-crown-6 in methanol solution yielded the title compound, C7H9BrN+·ClO4 −·C12H24O6. The protonated 4-bromo-3-methyl­amine unit contains one –NH3 + substituent, resulting in a 1:1 supra­molecular rotator–stator structure, (C7H9Br—NH3 +)(18-crown-6), through three bifurcated N—H⋯(O,O) hydrogen bonds between the ammonium group of the cation and the O atoms of the crown ether mol­ecule

Regulating Cytoplasmic Calcium Homeostasis Can Reduce Aluminum Toxicity in Yeast

Our previous study suggested that increased cytoplasmic calcium (Ca) signals may mediate aluminum (Al) toxicity in yeast (Saccharomyces cerevisiae). In this report, we found that a yeast mutant, pmc1, lacking the vacuolar calcium ion (Ca2+) pump Ca2+-ATPase (Pmc1p), was more sensitive to Al treatment than the wild-type strain. Overexpression of either PMC1 or an anti-apoptotic factor, such as Bcl-2, Ced-9 or PpBI-1, decreased cytoplasmic Ca2+ levels and rescued yeast from Al sensitivity in both the wild-type and pmc1 mutant. Moreover, pretreatment with the Ca2+ chelator BAPTA-AM sustained cytoplasmic Ca2+ at low levels in the presence of Al, effectively making the cells more tolerant to Al exposure. Quantitative RT-PCR revealed that the expression of calmodulin (CaM) and phospholipase C (PLC), which are in the Ca2+ signaling pathway, was down-regulated under Al stress. This effect was largely counteracted when cells overexpressed anti-apoptotic Ced-9 or were pretreated with BAPTA-AM. Taken together, our results suggest that the negative regulation of Al-induced cytoplasmic Ca signaling is a novel mechanism underlying internal resistance to Al toxicity