Parartemiopsis shangrilaensis, a new species of fairy shrimp (Branchiopoda, Anostraca) from Yunnan, with a key to the Chirocephalidae of China

The fairy shrimp genus Parartemiopsis Rogers, 2005 currently contains a single species reported from Russia and Mongolia. In 2013, an unidentified Parartemiopsis population was reported from the eastern margin of the Tibetan Plateau in China’s Yunnan Province, from Patatson National Park in Shangri-La County. Here, we describe the Chinese populations as a new species, Parartemiopsis shangrilaensis sp. nov. This new species is distinguished from its congener, P. longicornis (Smirnov, 1930), by the form of the male second antennae and the gonopod. The discovery of P. shangrilaensis sp. nov. extends the known distribution of the genus, and more Parartemiopsis species may be found in the future. We present a key to the genera and species of Chirocephalidae in China as an aid to future research

Astroconformer: The Prospects of Analyzing Stellar Light Curves with Transformer-Based Deep Learning Models

Light curves of stars encapsulate a wealth of information about stellar oscillations and granulation, thereby offering key insights into the internal structure and evolutionary state of stars. Conventional asteroseismic techniques have been largely confined to power spectral analysis, neglecting the valuable phase information contained within light curves. While recent machine learning applications in asteroseismology utilizing Convolutional Neural Networks (CNNs) have successfully inferred stellar attributes from light curves, they are often limited by the local feature extraction inherent in convolutional operations. To circumvent these constraints, we present $\textit{Astroconformer}$, a Transformer-based deep learning framework designed to capture long-range dependencies in stellar light curves. Our empirical analysis, which focuses on estimating surface gravity ($\log g$), is grounded in a carefully curated dataset derived from $\textit{Kepler}$ light curves. These light curves feature asteroseismic $\log g$ values spanning from 0.2 to 4.4. Our results underscore that, in the regime where the training data is abundant, $\textit{Astroconformer}$ attains a root-mean-square-error (RMSE) of 0.017 dex around $\log g \approx 3$. Even in regions where training data are sparse, the RMSE can reach 0.1 dex. It outperforms not only the K-nearest neighbor-based model ($\textit{The SWAN}$) but also state-of-the-art CNNs. Ablation studies confirm that the efficacy of the models in this particular task is strongly influenced by the size of their receptive fields, with larger receptive fields correlating with enhanced performance. Moreover, we find that the attention mechanisms within $\textit{Astroconformer}$ are well-aligned with the inherent characteristics of stellar oscillations and granulation present in the light curves.Comment: 13 pages, 9 figures, Submitted to MNRA

Cloning and characterization of two lipases and a lysophospholipase from aspergillus niger

We identified from a collection of partially sequenced Aspergillus niger cDNA clones four cDNAs that were predicted to encode secreted lipases or phospholipases B/lysophospholipases. The deduced amino acid sequence of two of the four genes, lipA and lipB, exhibited approximately 50% identity with each other and with a lipase from the thermophilic fungus Thermomyces lanuginosus. The other two cDNAs, plbA and plbB, share amino acid sequence 63% identity with each other and about 65% identity with Aspergillus fumigatus PlbAp. We functionally expressed the four genes in Pichia pastoris and A. niger, and purified and characterized the recombinant proteins. LipA showed optimal activity at 40°C and pH 4.5-5.0. LipA was stable at a pH range of 2.2-10.6 and up to 70°C. The pH optimum for LipB was pH 3.5-4.0, and it was stable between pH 3.0 and pH 9.6. The temperature optimum for LipB was 15°C and it retained 70% of its peak activity at 0°C. LipB has the lowest temperature activity profile when compared with reported cold-adapted enzymes. Substrate specificity determination with triacylglycerols and p -nitrophenyl esters showed that both lipases preferred esters with middle- and long-chain fatty acids. The pH optimum for the lysophospholipase activity encoded by PlbA was 3.0 and the activity was stable during incubation from pH 2 to 8.6. The temperature optimum of PlbA was 50°C and it retained at least 80% activity when incubated at 50°C for 3 h. PlbA exhibited a rather broad specificity towards lysophospholipids with maximal activity on lysophosphatidy1choline and lysophosphatidylserine and preferred the shorter C12 substrate relative to substrates with 14 to 18 carbons. PlbA did not exhibit phospholipase B, A1 or A2, lipase or general esterase activity and appeared to be lysophospholipid specific. PlbA lysophospholipase activity displayed cooperative kinetics with a Hill coefficient of 2.036. Recombinant PlbB could only be expressed at an extremely low level in both Pichia pastoris and Aspergillus niger. We were unable to purify and characterize this enzym