Optical frequency combs carrying optical angular momentum

To date, orbital angular momentum (OAM) and optical frequency combs (OFCs) are two distinct fields of research without any association. Herein, we generated OFCs with an OAM on each comb line by applying electro-optic phase modulation to the OAM beam. We verified that the OAM characteristic of the sidebands is consistent with that of the pump light. Our study bridges two distinct research fields OFCs and OAM opening the door to various fundamental research avenues and applications, including large-capacity optical communications, high-security optical encryption, multi-dimensional photon entanglement, and synthetic dimensions

Analytical computation of settlement displacement of buried pipeline caused by excavation

Excavation can induce the settlement deformation of adjacent buried pipeline. Obtaining the deformation is of great significance for evaluating the normal use and safety of pipeline. In this study, based on the elastic foundation beam theory, the calculation formula of the settlement displacement of buried pipeline is derived, and the influence of the two parameters of the surface center settlement and the calculation length on the settlement displacement of pipelines is emphatically analyzed. According to the geometric relationship between the buried pipeline and the edge of the foundation pit, the calculation length can be used to divide into five working conditions. The rationality of the analytical method is verified by comparing with two cases. In the case of excavation in Beijing, the spatio-temporal variation rules of settlement displacement of buried pipeline were analyzed. The results show that the variated trend of the calculated settlement displacement in different periods is consistent with that from measurement, but the calculated value is slightly higher than the measured value. The surface center settlement has a significant influence on the pipeline settlement displacement. larger input causes more concave settlement curve, and smaller input leads to smoother settlement curve. The decreasing rate of settlement displacement increases from the central point to end, and decreases near the boundary point, with the range of about one tenth of the calculated length. The proposed method in this study is conservative in the evaluation of pipeline settlement, which is a supplement to the existing settlement calculation theory of buried pipelines, and can provide a important information for predicting the distribution of pipeline settlement in the early stage of construction

A review of biohydrogen productions from lignocellulosic precursor via dark fermentation: perspective on hydrolysate composition and electron-equivalent balance

This paper reviews the current technological development of bio-hydrogen (BioH2) generation, focusing on using lignocellulosic feedstock via dark fermentation (DF). Using the collected reference reports as the training data set, supervised machine learning via the constructed artificial neuron networks (ANNs) imbedded with feed backward propagation and one cross-out validation approach was deployed to establish correlations between the carbon sources (glucose and xylose) together with the inhibitors (acetate and other inhibitors, such as furfural and aromatic compounds), hydrogen yield (HY), and hydrogen evolution rate (HER) from reported works. Through the statistical analysis, the concentrations variations of glucose (F-value = 0.0027) and acetate (F-value = 0.0028) were found to be statistically significant among the investigated parameters to HY and HER. Manipulating the ratio of glucose to acetate at an optimal range (approximate in 14:1) will effectively improve the BioH2 generation (HY and HER) regardless of microbial strains inoculated. Comparative studies were also carried out on the evolutions of electron equivalent balances using lignocellulosic biomass as substrates for BioH2 production across different reported works. The larger electron sinks in the acetate is found to be appreciably related to the higher HY and HER. To maintain a relative higher level of the BioH2 production, the biosynthesis needs to be kept over 30% in batch cultivation, while the biosynthesis can be kept at a low level (2%) in the continuous operation among the investigated reports. Among available solutions for the enhancement of BioH2 production, the selection of microbial strains with higher capacity in hydrogen productions is still one of the most phenomenal approaches in enhancing BioH2 production. Other process intensifications using continuous operation compounded with synergistic chemical additions could deliver additional enhancement for BioH2 productions during dark fermentation

A review of enhancement of biohydrogen productions by chemical addition using a supervised machine learning method

In this work, the impact of chemical additions, especially nano‐particles (NPs), was quan-titatively analyzed using our constructed artificial neural networks (ANNs)‐response surface methodology (RSM) algorithm. Fe‐based and Ni‐based NPs and ions, including Mg2+, Cu2+, Na+, NH4+, and K+, behave differently towards the response of hydrogen yield (HY) and hydrogen evolution rate (HER). Manipulating the size and concentration of NPs was found to be effective in enhancing the HY for Fe‐based NPs and ions, but not for Ni‐based NPs and ions. An optimal range of particle size (86–120 nm) and Ni‐ion/NP concentration (81–120 mg L−1) existed for HER. Meanwhile, the manipulation of the size and concentration of NPs was found to be ineffective for both iron and nickel for the improvement of HER. In fact, the variation in size of NPs for the enhancement of HY and HER demonstrated an appreciable difference. The smaller (less than 42 nm) NPs were found to definitely improve the HY, whereas for the HER, the relatively bigger size of NPs (40–50 nm) seemed to significantly increase the H2 evolution rate. It was also found that the variations in the concentration of the investigated ions only statistically influenced the HER, not the HY. The level of response (the enhanced HER) towards inputs was underpinned and the order of significance towards HER was identified as the following: Na+ \u3e Mg2+ \u3e Cu2+ \u3e NH4+ \u3e K+

MapSplice: Accurate Mapping of RNA-Seq Reads for Splice Junction Discovery

The accurate mapping of reads that span splice junctions is a critical component of all analytic techniques that work with RNA-seq data. We introduce a second generation splice detection algorithm, MapSplice, whose focus is high sensitivity and specificity in the detection of splices as well as CPU and memory efficiency. MapSplice can be applied to both short (\u3c75 bp) and long reads (≥75 bp). MapSplice is not dependent on splice site features or intron length, consequently it can detect novel canonical as well as non-canonical splices. MapSplice leverages the quality and diversity of read alignments of a given splice to increase accuracy. We demonstrate that MapSplice achieves higher sensitivity and specificity than TopHat and SpliceMap on a set of simulated RNA-seq data. Experimental studies also support the accuracy of the algorithm. Splice junctions derived from eight breast cancer RNA-seq datasets recapitulated the extensiveness of alternative splicing on a global level as well as the differences between molecular subtypes of breast cancer. These combined results indicate that MapSplice is a highly accurate algorithm for the alignment of RNA-seq reads to splice junctions. Software download URL: http://www.netlab.uky.edu/p/bioinfo/MapSplice

Impaired Iron Status in Aging Research

Aging is associated with disturbances in iron metabolism and storage. During the last decade, remarkable progress has been made toward understanding their cellular and molecular mechanisms in aging and age-associated diseases using both cultured cells and animal models. The field has moved beyond descriptive studies to potential intervention studies focusing on iron chelation and removal. However, some findings remain controversial and inconsistent. This review summarizes important features of iron dyshomeostasis in aging research with a particular emphasis on current knowledge of the mechanisms underlying age-associated disorders in rodent models

Duals of Bernoulli Numbers and Polynomials and Euler Numbers and Polynomials

Oral presentation abstract

Butterfly Community Diversity in the Qinling Mountains

The Qinling Mountains are one of the oldest mountain ranges in China and a global biodiversity research and conservation hotspot. However, there is a lack of systematic research and survey of butterfly diversity in this region. Based on the butterfly taxa, combined with the changes in natural climate, altitude gradient and season in the Qinling Mountains, the butterfly diversity and community structure changes in 12 counties in the middle Qinling Mountains were analyzed by transect surveys and platform data analyses. A total of 9626 butterflies were observed, belonging to 427 species across 175 genera and 5 families. The species richness on the southern slope of the Qinling Mountains was higher than on the northern slope. We also studied the variation in alpha and beta diversity of butterflies. The results show that butterfly species were abundant and the highest diversity was found at the middle altitudes (1000–2000 m). Moreover, there were obvious seasonal differences in both species and number of butterflies. The community similarity in spring, summer and autumn was low, with limited species co-existing. The butterflies in the Qinling Mountains reserve area were the most abundant, exhibiting no significant difference with those in the ecotone and the farm area. Finally, we did an assessment of butterflies as endangered and protected species. In conclusion, our long-term butterfly survey data show that human disturbance and climate and environmental changes jointly shape the butterfly diversity in the middle of the Qinling Mountains