Biological parameters estimate for the sickle pomfret (Taractichthys steindachneri) in the west-central and eastern Pacific Ocean

373-381This study was undertaken to provide some preliminary biological information for Sickle pomfrets Taractichthys steindachneri from length frequency data (LFD) obtained through the Chinese Longline Fisheries Observer Programme in the Pacific Ocean obtained from August 2016 to March 2017. We fitted the seasonally oscillating von Bertalanffy Growth Function (so VBGF) by applying two optimized ELEFAN approaches ('simulated annealing' ELEFAN S.A. and 'genetic algorithm' ELEFAN G.A.). ELEFAN S.A. presented the best score and was later used to obtain the following results:  FL∞ = 101 cm, k = 0.52 yr−1, t_anchor = 0.73, C = 0.75, ts = 0.2, and growth performance index of ∅ = 3.72; natural mortality  M = 0.55 yr−1, total mortality Z = 1.37 yr−1, fishing mortality F = 0.82 yr−1, exploitation rate E = 0.59, length at first sexual maturity Lm = 67.5 cm corresponding to 2.47 years (age at first sexual maturity); major recruitment and highest catch rate occurred in January. F and E at maximum sustainable yield were Fmsy = 1.7 yr-1 and Emsy = 0.754, respectively. In this study, E and results of yield-per-recruit models indicate that these fisheries are sustainably harvested, and maximum sustainable yield could be acquired, if F is increased to Fmsy

A case with sarcomatoid hepatocellular carcinoma and literature review

Sarcomatoid hepatocellular carcinoma (SHC) is a relatively rare subtype of liver cancer reported in 1.8–2.0% of surgically resected cases. Previous studies have found that SHC was more likely to occur in patients who received repeated anticancer therapies, but the underlying mechanism has not been exactly illustrated. We report a case of a 62-year-old man with SHC. With the initial implication of abscess suspected liver mass by radiological exams (enhanced Computed Tomography and liver Magnetic Resonance Imaging), the patient underwent a laparoscopic pus debridement and biopsy. The diagnosis of SHC was considered by pathologists. After a short recovery, a second radical resection of the liver tumor and hepatic hilar lymph node dissection were conducted. Postoperative pathology revealed a tumor-free incisal margin and negative lymph node. The recovery of the patient was uneventful. When confronting an occasional liver mass with previous Hepatitis B virus infection, SHC should be included for a candidate diagnosis. If diagnosis is confirmed, high biological malignancy and poor survival should be expected. Surgery is still a main option to treat SHC

Re-Fracturing vs. CO2 Huff-n-Puff Injection in a Tight Shale Reservoir for Enhancing Gas Production

Field production data indicate that the shale gas production rate decreases sharply after a few years of the first fracking. Feasible enhanced gas recovery (EGR) approaches are very necessary to be investigated. In this study, we compared re-fracturing with a huff-n-puff gas injection scheme in a shale gas reservoir for EGR. A fully compositional simulation approach coupled with a dual porosity and dual permeability model is used. The gas production performances by using different fracturing fluids (i.e., slickwater and supercritical CO2) are evaluated. The effects of huff-n-puff parameters and matrix permeability on the gas production rate and carbon sequestration are investigated. The results show that using a re-fracturing approach yields a better recovery performance than the huff-n-puff gas injection method. Re-fracturing using supercritical CO2 performs better than using slickwater because the former can create complex three-dimensional fracture networks. Huff-n-puff CO2 injection can enhance the gas recovery effectively in ultra-tight formations. In a relatively high permeable formation, viscous flow instead of adsorption-desorption isotherms becomes the primary mass transfer mechanisms, resulting in a lower gas recovery. Both the re-fracturing treatment and huff-n-puff CO2 injection are profitable from a long-term cash flowback perspective

Effect of elevation on composition and diversity of fungi in the rhizosphere of a population of Deyeuxia angustifolia on Changbai Mountain, northeastern China

Soil fungi are a key component of terrestrial ecosystems and play a major role in soil biogeochemical cycling. Although the diversity and composition of fungal communities are regulated by many abiotic and biotic factors, the effect of elevation on soil fungal community diversity and composition remains largely unknown. In this study, the soil fungal composition and diversity in Deyeuxia angustifolia populations along an elevational gradient (1,690 m to 2020 m a.s.l.) were assessed, using Illumina MiSeq sequencing, on the north-facing slope of the Changbai Mountain, northeastern China. Our results showed that soil physicochemical parameters changed significantly along with the elevational gradients. The Ascomycota and Basidiomycota were the most dominant phyla along with the gradient. Alpha diversity of soil fungi decreased significantly with elevation. Soil nitrate nitrogen (NO3−-N) was positively correlated with fungal richness and phylogenetic diversity (PD), indicating that soil nitrate nitrogen (NO3−-N) is a key soil property determining fungal community diversity. In addition to soil nitrate content, soil pH and soil moisture were the most important environmental properties determining the soil fungal diversity. Our results suggest that the elevational changes in soil physicochemical properties play a key role in shaping the community composition and diversity of soil fungi. This study will allow us to better understand the biodiversity distribution patterns of soil microorganisms in mountain ecosystems

Oroxylin A promotes PTEN-mediated negative regulation of MDM2 transcription via SIRT3-mediated deacetylation to stabilize p53 and inhibit glycolysis in wt-p53 cancer cells

Introduction p53 plays important roles in regulating the metabolic reprogramming of cancer, such as aerobic glycolysis. Oroxylin A is a natural active flavonoid with strong anticancer effects both in vitro and in vivo. Methods wt-p53 (MCF-7 and HCT116 cells) cancer cells and p53-null H1299 cancer cells were used. The glucose uptake and lactate production were analyzed using Lactic Acid production Detection kit and the Amplex Red Glucose Assay Kit. Then, the protein levels and RNA levels of p53, mouse double minute 2 (MDM2), and p53-targeted glycolytic enzymes were quantified using Western blotting and quantitative polymerase chain reaction (PCR), respectively. Immunoprecipitation were performed to assess the binding between p53, MDM2, and sirtuin-3 (SIRT3), and the deacetylation of phosphatase and tensin homolog (PTEN). Reporter assays were performed to assess the transcriptional activity of PTEN. In vivo, effects of oroxylin A was investigated in nude mice xenograft tumor-inoculated MCF-7 or HCT116 cells. Results Here, we analyzed the underlying mechanisms that oroxylin A regulated p53 level and glycolytic metabolism in wt-p53 cancer cells, and found that oroxylin A inhibited glycolysis through upregulating p53 level. Oroxylin A did not directly affect the transcription of wt-p53, but suppressed the MDM2-mediated degradation of p53 via downregulating MDM2 transcription in wt-p53 cancer cells. In further studies, we found that oroxylin A induced a reduction in MDM2 transcription by promoting the lipid phosphatase activity of phosphatase and tensin homolog, which was upregulated via sirtuin3-mediated deacetylation. In vivo, oroxylin A inhibited the tumor growth of nude mice-inoculated MCF-7 or HCT116 cells. The expression of MDM2 protein in tumor tissue was downregulated by oroxylin A as well. Conclusions These results provide a p53-independent mechanism of MDM2 transcription and reveal the potential of oroxylin A on glycolytic regulation in both wt-p53 and mut-p53 cancer cells. The studies have important implications for the investigation on anticancer effects of oroxylin A, and provide the academic basis for the clinical trial of oroxylin A in cancer patients

Approximation-Based Fixed-Time Adaptive Tracking Control for a Class of Uncertain Nonlinear Pure-Feedback Systems

This paper examines approximation-based fixed-time adaptive tracking control for a class of uncertain nonlinear pure-feedback systems. Novel virtual and actual controllers are designed that resolve the meaninglessness of virtual and actual controllers at the origin and in the negative domain, and the sufficient condition for the system to have semiglobal fixed-time stability is also provided. Radial basis function neural networks are introduced to approximate unknown functions for solving the fixed-time control problem of unknown nonlinear pure-feedback systems, and the mean value theorem is used to solve the problem of nonaffine structure in nonlinear pure-feedback systems. The controllers designed in this paper ensure that all signals in the closed-loop system are semiglobally uniform and ultimately bounded in a fixed time. Two simulation results show that appropriate design parameters can limit the tracking error within a region of the origin in a fixed time

Environmental Characteristics Associated with the Presence of the Pelagic Stingray (<i>Pteroplatytrygon violacea</i>) in the Pacific High Sea

The pelagic stingray (Pteroplatytrygon violacea), perhaps the only stingray to inhabit open ocean waters, is highly interactive with longline and purse seine fisheries. The threat to P. violacea posed by high bycatch mortality has received widespread attention. To date, the environmental preference of P. violacea, which is important in designing conservation and management measures, has not been well studied. Based on data collected during a 2016–2019 survey in the Pacific Ocean by national observers of tuna longline fisheries, the relationship between the presence of P. violacea and spatiotemporal and environmental variables was first analyzed using the Generalized Additive Model. The results showed that geographic location (latitude and longitude) was the most influential variable. Monthly, P. violacea is frequently present in the Pacific high sea from December to May. The El Niño–Southern Oscillation had a significant impact on the presence of P. violacea in the Pacific high sea, with both the cold (Ocean Nino Index 1) phases leading to a decrease in its presence. Regarding the environmental factors, we found that high presence was associated with low salinity (33.0~34.5 psu), a relatively high concentration of chlorophyll (0.2–0.35 mg/m3), and warm water (>20 °C). P. violacea was most likely observed in the waters offshore, closer to seamounts, and with water depths between 4000 and 5000 m. Four areas, including those east of the Solomon Islands and east of Kiribati, areas west of the Galapagos Islands, and areas near the coastal upwelling of northern Peru, related to upwelling systems or seamounts, were identified as the potential key habitats of P. violacea. Predicted distribution maps showed a significant seasonal variation in the presence of P. violacea. Moreover, the yearly change in the presence of P. violacea in the Pacific high sea indicated a possible decreasing trend in recent years. The information first provided here is essential for developing conservation and management measures for P. violacea to prevent the unavoidable ecological consequences of bycatch or other anthropogenic factors