Chemical-free Extraxtion of Cotton Stalk Bark Fibers by Steam Flash Explosion

Cotton stalk bark fibers (CSBF) were extracted by steam flash explosion, completed within 0.09 s, and the extracted fibers were compared with those obtained by conventional alkaline treatment. Results indicate that the optimum steam pressure was 2.5 MP a when steaming time was set to 2 min for extracting CSBF. Under the optimized conditions, the obtained CBSF had a cellulose content of 72%, length of 48 mm, fineness of 45 dtex, crystallinity index of 68, moisture regain of 8%, water rention of 98%, and tensile strength of 2.4 cN/dtex, which were similar to results obtained by conventional alkaline treatment. Compared with bark of cotton stalks, CSBF had lower moisture regain and water retention, and higher onset decomposition temperature. The results sow that moderate steam flash explosion is a chemical-free, quick, and effective method for exploring the industrial applications of bark of cotton stalks as natural cellulose fibers

Genome-Wide Identification of Early-Firing Human Replication Origins by Optical Replication Mapping [preprint]

The timing of DNA replication is largely regulated by the location and timing of replication origin firing. Therefore, much effort has been invested in identifying and analyzing human replication origins. However, the heterogeneous nature of eukaryotic replication kinetics and the low efficiency of individual origins in metazoans has made mapping the location and timing of replication initiation in human cells difficult. We have mapped early-firing origins in HeLa cells using Optical Replication Mapping, a high-throughput single-molecule approach based on Bionano Genomics genomic mapping technology. The single-molecule nature and 290-fold coverage of our dataset allowed us to identify origins that fire with as little as 1% efficiency. We find sites of human replication initiation in early S phase are not confined to well-defined efficient replication origins, but are instead distributed across broad initiation zones consisting of many inefficient origins. These early-firing initiation zones co-localize with initiation zones inferred from Okazaki-fragment-mapping analysis and are enriched in ORC1 binding sites. Although most early-firing origins fire in early-replication regions of the genome, a significant number fire in late-replicating regions, suggesting that the major difference between origins in early and late replicating regions is their probability of firing in early S-phase, as opposed to qualitative differences in their firing-time distributions. This observation is consistent with stochastic models of origin timing regulation, which explain the regulation of replication timing in yeast

Chemical-free Extraxtion of Cotton Stalk Bark Fibers by Steam Flash Explosion

Cotton stalk bark fibers (CSBF) were extracted by steam flash explosion, completed within 0.09 s, and the extracted fibers were compared with those obtained by conventional alkaline treatment. Results indicate that the optimum steam pressure was 2.5 MP a when steaming time was set to 2 min for extracting CSBF. Under the optimized conditions, the obtained CBSF had a cellulose content of 72%, length of 48 mm, fineness of 45 dtex, crystallinity index of 68, moisture regain of 8%, water rention of 98%, and tensile strength of 2.4 cN/dtex, which were similar to results obtained by conventional alkaline treatment. Compared with bark of cotton stalks, CSBF had lower moisture regain and water retention, and higher onset decomposition temperature. The results sow that moderate steam flash explosion is a chemical-free, quick, and effective method for exploring the industrial applications of bark of cotton stalks as natural cellulose fibers

Identifying and Counting Tobacco Plants in Fragmented Terrains Based on Unmanned Aerial Vehicle Images in Beipanjiang, China

Refined tobacco plant information extraction is the basis of efficient yield estimation. Tobacco planting in mountainous plateau areas in China is characterized by scattered distribution, uneven growth, and mixed/intercropping crops. Thus, it is difficult to accurately extract information on the tobacco plants. The study area is Beipanjiang topographic fracture area in China, using the smart phantom 4 Pro v2.0 quadrotor unmanned aerial vehicle to collect the images of tobacco planting area in the study area. By screening the visible light band, Excess Green Index, Normalized Green Red Difference Vegetation Index, and Excess Green Minus Excess Red Index were used to obtain the best color index calculation method for tobacco plants. Low-pass filtering was used to enhance tobacco plant information and suppress noise from weeds, corn plants, and rocks. Combined with field measurements of tobacco plant data, the computer interactive interpretation method performed gray-level segmentation on the enhanced image and extracted tobacco plant information. This method is suitable for identifying tobacco plants in mountainous plateau areas. The detection rates of the test and verification areas were 96.61% and 97.69%, and the completeness was 95.66% and 96.53%, respectively. This study can provide fine data support for refined tobacco plantation management in the terrain broken area with large exposed rock area and irregular planting land

A Review of Eco-Product Value Realization and Ecological Civilization and Its Enlightenment to Karst Protected Areas

The current ecosystem services of karst protected areas cannot fully enhance human well-being, and the value of eco-products cannot be effectively realized. Research on eco-products and ecological civilization is conducive to the regional sustainability. The results of a statistical analysis of 258 related articles indicate: (1) the number of published articles has increased rapidly after slow growth, indicating that this research field has become a research hotspot and has broad research prospects; (2) the research content mainly involves five aspects, such as eco-product supply, eco-product value realization, eco-industry, ecological civilization, and monitoring and evaluation; (3) the articles research area is mainly distributed in the karst areas with a fragile ecological environment in China and the eco-product value realization and ecological civilization pilot areas; (4) the research frontiers are revealed from four aspects of eco-product supply ability, eco-product value realization, the driving force of eco-product value realization on the formation of eco-industry, model and effectiveness of ecological civilization; (5) it is necessary to deepen the research on the improvement mechanism of eco-product supply capacity, the classification systems and value accounting standards of eco-products, the formation mechanism of eco-industries under ecological threshold constraints and the driving mechanism of eco-industry to ecological civilization

Identifying and Counting Tobacco Plants in Fragmented Terrains Based on Unmanned Aerial Vehicle Images in Beipanjiang, China

Refined tobacco plant information extraction is the basis of efficient yield estimation. Tobacco planting in mountainous plateau areas in China is characterized by scattered distribution, uneven growth, and mixed/intercropping crops. Thus, it is difficult to accurately extract information on the tobacco plants. The study area is Beipanjiang topographic fracture area in China, using the smart phantom 4 Pro v2.0 quadrotor unmanned aerial vehicle to collect the images of tobacco planting area in the study area. By screening the visible light band, Excess Green Index, Normalized Green Red Difference Vegetation Index, and Excess Green Minus Excess Red Index were used to obtain the best color index calculation method for tobacco plants. Low-pass filtering was used to enhance tobacco plant information and suppress noise from weeds, corn plants, and rocks. Combined with field measurements of tobacco plant data, the computer interactive interpretation method performed gray-level segmentation on the enhanced image and extracted tobacco plant information. This method is suitable for identifying tobacco plants in mountainous plateau areas. The detection rates of the test and verification areas were 96.61% and 97.69%, and the completeness was 95.66% and 96.53%, respectively. This study can provide fine data support for refined tobacco plantation management in the terrain broken area with large exposed rock area and irregular planting land

Beneficial effects of upgrading to His-Purkinje system pacing in patients with pacing-induced cardiomyopathy: a systematic review and meta-analysis

Background The purpose of this study was to evaluate the effectiveness of His-Purkinje system pacing (HPSP) in the management of patients with pace-induced cardiomyopathy (PICM). Methods PubMed, Embase, Web of Science, and the Cochrane Library were searched comprehensively to collect related studies published from the inception of databases to June 1, 2022. R 4.04 software, including the Metafor package, matrix package, and the Meta package, was utilized to conduct the singe-arm meta-analysis. The methodology index for non-randomized studies (MINORS) was used to assess the methodological quality of the included studies. Results A total of seven studies were included, involving 164 PICM patients. The meta-analysis showed that HPSP ameliorated the left ventricular ejection fraction (LVEF) by 13.41% (95% CI [11.21–15.61]), improved the New York Heart Association (NYHA) classification by 1.02 (95% CI [−1.41 to −0.63]), and shortened the QRS duration (QRSd) by 60.85 ms (95% CI [−63.94 to −57.75]), resulting in improved cardiac functions in PICM patients. Besides, HPSP reversed the ventricular remodeling, with a 32.46 ml (95% CI [−53.18 to −11.75]) decrease in left ventricular end systolic volume (LVESV) and a 5.93 mm (95% CI [−7.68 to −4.19]) decrease in left ventricular end-diastolic dimension (LVEDD). HPSP also showed stable electrical parameters of pacemakers, with a 0.07 V (95% CI [0.01–0.13]) increase in pacing threshold, a 0.02 mV (95% CI [−0.85 to 0.90]) increase in sensed R-wave amplitude, and a 31.12 Ω reduction in impedance (95% CI [−69.62 to 7.39]). Compared with LBBP, HBP improved LVEF by 13.28% (95% CI [−11.64 to 14.92]) vs 14.43% (95% CI [−13.01 to 15.85]), ameliorated NHYA classification by 1.18 (95% CI [−1.97 to −0.39]) vs 0.95 (95% CI [−1.33 to −0.58]), shortened QRSd by 63.16 ms (95% CI [−67.00 to −59.32]) vs 57.98 ms (95% CI [−62.52 to −53.25]), and decreased LVEDD by 4.12 mm (95% CI [−5.79 to −2.45]) vs 6.26 mm (95% CI [−62.52 to −53.25]). The electrical parameters of the pacemaker were stable in both groups. Conclusions This meta-analysis showed that HPSP could significantly improve cardiac function, promote reverse remodeling, and provide stable electrical parameters of pacemakers for PICM patients

Thiol functionalized mesoporous silicas for selective adsorption of precious metals

Thiol functionalized mesoporous silica (TFMS) with ordered hexagonal pore structure was fabricated by one-step synthesis pathway. The selective adsorption for precious metals was investigated using single component and binary adsorption solutions. The TFMS displayed strong affinity for gold or platinum in specific conditions with a large adsorption capacity, and showed a high selectivity in the binary solutions within 30 min. Furthermore, gold and platinum could be totally recovered by elution with 5 M HCl and 0.7 M thiourea-2 M HCl, respectively. (C) 2012 Elsevier Ltd. All rights reserved