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Extraction of tobacco extracts from tobacco leaf scraps can promote the maximum utilization of tobacco waste and offer tobacco industries a formula to improve cigarette qualities and flavors. Tobacco extracts can be used as a reconstituted tobacco coating solution for reconstituted tobacco sheet (RTS)-based paper. Aroma components in the tobacco extracts can determine the fragrance style of the RTS. However, traditional extraction methods usually have many problems. Herein, the ultrasound-assisted enzymatic hydrolysis was first applied to improve the aroma of tobacco extracts from tobacco leaf scraps. After ultrasound-assisted enzymatic hydrolysis, the total aroma components content in tobacco extracts was increased by 5.0 times compared with that in aqueous extracts, and the total extraction yield was increased by 51.57%. Moreover, other compositions in tobacco extracts, including total sugar, nicotine, lignin, total phenols, formic acid, and acetic acid were also increased. This study provides a method to improve the aroma in the tobacco extracts and the quality of RTS. [ABSTRACT FROM AUTHOR]

Biomass briquetting is gradually emerging as a means of sustainable energy production. The interest in briquetting has been occasioned by the continuous rise in the cost of energy coupled with the need to harness efficient and affordable alternatives. Briquettes are produced through various means, ranging from a simple low-pressured technique to a high-pressured technique. This, including the large-scale availability of biomass materials in many regions of the world, has made the process practicable and affordable. The technology has gained acceptance across the scientific community as it is a means of attaining a circular and green economy especially as it helps to curtail deforestation. Briquetting has advanced and now incorporates the blending of biomass with animal and municipal wastes such as dung, microalgae, plastics, sludge, and food waste. This paper reviewed recent literature spanning over a decade on the technical aspects of biomass briquetting to establish the current state of research. It contains a brief on renewable energy with a focus on biomass energy, as well as the impact of solid fuels on households and the environment. It reviewed briquettes and briquetting technology by highlighting key processes and quality parameters. The paper also reports the economic aspects of various briquetting technology to assess their viability and also reports the combustion process to evaluate the extent of toxic gas emissions and their impact on coal-based power plants. To this end, an overview of recent studies was made followed by a highlight of recent advancements in briquetting technology. [ABSTRACT FROM AUTHOR]

TC25G alloy was heat treated at 950 °C/3 h, AC + 580 °C/6 h, AC and the bimodal structure with primary α phase + β transition structure was obtained. The creep properties of the alloy were tested in 550–600 °C/150–250 MPa. The results show that the precipitations of silicide and α2 phase is accompanied by the creep process. α2 phase plays a dispersion strengthening role in both the primary and steady-state creep stages. However, in the accelerated creep stage, the mechanism of α2 phase and dislocation changes from cutting mechanism to bypassing mechanism, and the strengthening effect is weakened. Silicide inhibits grain boundary slip mainly in the primary creep stage, and inhibits dislocation slip in the steady-state and accelerated creep stages. At 550 °C, n = 1.6 and Q = 280–371 kJ/mol (150–250 MPa) indicate that the creep of the alloy is a self-diffusion process, and the creep deformation is mainly controlled by dislocation slip. At 570–600 °C, n = 3.2 indicates that the dislocation climb controls the creep deformation. Meanwhile, compared with Q = 274 kJ/mol at low stress (150 MPa), Q = 365 kJ/mol at the high stress (200–250 MPa) indicates that the second phase precipitation enhancement is enhanced. [ABSTRACT FROM AUTHOR]

The ER5183 is used as filler metal, and the Al–Li alloy is welded by electron beam welding. The microstructure and mechanical property of welded joint are investigated. Results show that, under the proper welding procedure, the joint with good appearance of weld is obtained. The fusion zone is mainly composed of α-Al matrix phase and some strengthening phases involving θ′(Al2Cu), T2(Al6CuLi3), T1(Al2CuLi) and δ′(Al3Li). The grains in weldment are refined by the addition of electron beam scanning. Compared with that of the base metal (BM), the microhardness in weld zone is decreased to a certain extent. Under the welding condition of square wave electron beam scanning, the tensile strength of welded joint is 352.2 MPa, which is 70.2% of that of the BM. There exists obvious dimple morphology on the joint fracture surface, and it presents the characteristic of intergranular fracture. [ABSTRACT FROM AUTHOR]

Titanium and its alloys exhibit a favorable integration of characteristics, including notable strength and high resistance to corrosion. However, they are deficient in terms of wear resistance and thermal conductivity, among other properties. The aforementioned limitations impose constraints on the utilization of these alloys across diverse applications. Currently, various strategies involving the utilization of composite materials are being implemented in order to address and mitigate these previously mentioned limitations. The utilization of micro- or nano-sized reinforcements has been employed to improve the characteristics of the metal matrix. Diverse techniques are employed to uniformly distribute the reinforcement within the matrix, thereby generating titanium metal matrix composites (TMCs). The use of TMCs has become increasingly prevalent in diverse sectors, including defense, automotive, aerospace, and biomedical, owing to their remarkable characteristics, which encompass lower weight, higher specific strength, and compatibility with biological systems. The present study discusses various manufacturing techniques, including spark plasma sintering (SPS), additive manufacturing, and vacuum melting. This study further examines different reinforcements that are considered in the production of TMCs. The current study also investigates the effects of reinforcements on properties such as mechanical and tribological characteristics. The study demonstrated that the incorporation of reinforcements resulted in enhanced properties. [ABSTRACT FROM AUTHOR]

One of the most serious ecological problems affecting drylands worldwide is sandification, due to exacerbation of the desertification process. As sandified land grows larger, the potential for agriculture decreases. Particularly in Pakistan, desertification is also a significant issue, with numerous natural and human-caused contributors. Desertification often occurs in Pakistan's south Punjab's dry lands, and regularly monitoring the area's sandification dynamics can assist in mitigating the problem. The purpose of this study is to determine the sensitivity to the sandification phenomenon in South Punjab drylands (Rajanpur, Rahim Yar Khan, and Bahawalpur) Pakistan. ALOS PALSAR DEM of 12.5 m resolution and Level 2 Landsat 5, 7, and 8 data (1988, 2001, and 2018) were utilized to conduct this research. The sensitivity to sandification was determined using land use land cover (LULC), slope, and aspect as the determining variables. These variables were separately integrated into ArcGIS using the weighted sum approach for the years 1988, 2001, and 2018. The analysis of sensitivity to sandification found that insensitive land expanded by 47 percent between 1988 and 2018, whereas very low sensitive and low sensitive classifications declined by -5.95 percent and -9.23 percent, respectively. The moderately sensitive area to sandification saw the largest percentage change between 1988 and 2018, changing by 1095.52%. The desertified land saw the second-largest percentage change, changing by 521.58%. However, the highly sensitive to sandification class showed the greatest percentage decrease (-53.65%). The most significant factor found to have an impact on the local sandification dynamics was LULC. By continuously monitoring the dynamics of sandification, the region's desertification intensity can be reduced. A Decision Support System (DSS) can be developed for this purpose through further study. Policymakers can use the DSS findings to assist them in creating strategies for reducing desertification in this region. [ABSTRACT FROM AUTHOR]

Titanium matrix composites (TMCs) have garnered substantial attention from researchers owing to their outstanding properties. Nonetheless, the strength and ductility of TMCs hardly co-exist and often show a trade-off between each other. In this study, we employ an ultra-thin graphite powder sheet as the carbon source and employ Ti/C composites with varying carbon contents, prepared via a layer-stacked laminated sintering method, to ensure a comprehensive in-situ reaction and uniform reinforcement distribution. With increasing carbon content, noticeable alterations occur in the size, concentration, and morphology of the titanium carbide (TiC) particles. The increase of TiC particle content is found to boost the ultimate tensile strength of the composite. However, this improvement comes at the expense of reduced elongation. Notably, as the carbon content reaches 1.81 wt%, the yield strength and ultimate tensile strength of the composites soar to 354.4 MPa and 575.4 MPa, respectively. These values represent a remarkable increase of 75.4% and 65.0% compared to pure titanium, while maintaining an acceptable elongation of 6.45%. This study unveils a promising approach for significantly enhancing the mechanical properties of titanium alloys. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate the desertification vulnerability and the future trends of desertification expansion in the Bahawalpur division of Punjab, Pakistan. This aim is achieved by analyzing Landsat data between the years 1990 and 2019. The biophysical index and socio-economic index were used to identify the Desertification Vulnerability Index (DVI) and its changes which have taken place over the study period between the years 1990 and 2019. The findings indicated that there was a decrease in the rate of desertification vulnerability from 1990 to 2019. In addition, the central and southern part of the Bahawalpur division is classified as a highly vulnerable zone in comparison to the other part of the region. The overall results show that the barren land and the desert area have been showing a decreasing trend, accompanied by substantial growth in vegetation from 1990 to 2019. The findings of the DVI analysis indicate that the Highly Vulnerable Area has decreased spatially from 61.12 in 1990 to 55.3% in 2019, while the Moderately Vulnerable Area and the Least Vulnerable Area have grown from 25.59% and 17.2% in 1990 to 28.56 and 19.53% in 2019, respectively. The decreasing trend demonstrates the effectiveness of efforts to combat desertification and the government could develop the best strategies for rehabilitation works and control the land degradation process in the most vulnerable areas in the Bahawalpur division of Punjab, Pakistan. [ABSTRACT FROM AUTHOR]

As one of the most representative Paleoproterozoic orogenic belts in the North China Craton, the Jiao-Liao-Ji Belt is of great significance to explore the Paleoproterozoic tectonic evolution of the North China Craton, as well as the convergence process of the Columbia Supercontinent. In this study, we present new geochronological and geochemical data of Paleoproterozoic meta-mafic rocks in the Southern Jilin Province, NE China. Our primary objective is to further constraint the formation and evolution of the Jiao-Liao-Ji Belt. The zircon U–Pb dating reveals that the meta-mafic rocks crystallized at 2.2–2.0 Ga, followed by a metamorphism occurring at ~ 1.9 Ga. Additionally, most of the mafic rocks display moderate fractionation in both light rare earth elements (LREEs) and heavy rare earth elements (HREEs), suggesting their association with an arc setting. Furthermore, the rocks also display an enrichment in large ion lithophile elements (LILEs) such as Cs, Rb, Ba, and Pb, and depletion in high field strength elements (HSFEs) including Nb, Ta, Zr, and Ti. These geochemical characteristics suggest a back-arc setting, indicating that the meta-mafic rocks originated from asthenospheric mantle that was metasomatized by fluids or melts derived from the subducting slab. Notably, a shoshonitic metabasalt exhibits trace element and REEs patterns that resemble those of ocean–island basalts. This suggests that the shoshonitic metabasalt was formed in an oceanic island environment, likely generated from the asthenospheric mantle. Combining these findings with previous studies, we can conclude that the Jiao-Liao-Ji Belt is associated with arc–continental collision, indicating the presence of a modern-type plate tectonic regime in the northeastern North China Craton during the Paleoproterozoic period. [ABSTRACT FROM AUTHOR]

Background and aims : The problem of desertification is becoming increasingly serious in the Zoige Plateau. How to carry out vegetation restoration more efficiently in desertified area has been a hotspot. This study aims to improve the vegetation restoration capacity in the desertified area of Zoige Plateau. Methods: In this study, Elymus sibiricus, Elymus dahuricus Turcz and Avena sativa were used as restoration plants in desertified areas. The application concentrations of palygorskite fertilizers (PF), bacterial fertilizers (BF) and phyto-hormones were determined by orthogonal test. The restoration effects were determined based on the fractional vegetation cover (FVC), soil physicochemical properties and soil microbial community after restoration. Results: The results showed that FVC was improved in desertified lands through the addition of PF, BF and phyto-hormones, and the best performance of the combined application improved the FVC up to 67.9%. Meanwhile, the contents of available phosphorus and available nitrogen were also significantly increased compared with the control. Moreover, 16S sequencing analysis showed that Flavobacteria and Herbaspirillum were increased in the plots with high FVC compared to the ones in the control (p < 0.05). Functional prediction by using Tax4Fun revealed that the KEGG pathways of bacteria in the plots with high FVC were enriched for oxidation and amino associated enzymes. Conclusion: The addition of fertilizers and phytohormones improves FVC in desertified areas, and this improvement may be caused by increased soil nutrients and some functional soil microorganisms. [ABSTRACT FROM AUTHOR]

Unsupervised anomaly detection techniques mainly model the population distribution of geochemical exploration data, but do not consider the mineral deposit information found in the study area. Supervised classification techniques can make full use of mineral deposit information to distinguish geochemical anomalies from the background. However, these classification techniques usually cannot properly address the data imbalance in distinguishing geochemical anomalies from the background. The data imbalance of geochemical exploration data means that there are only a few known mineralized data points in the study area and a large number of data points to be evaluated. Semi-supervised classification techniques are machine learning algorithms developed to solve the classification problem of a small amount of labeled data and a large amount of unlabeled data. These techniques are suitable for dealing with classification problems such as identifying anomalies from geochemical exploration data. Therefore, in this study, the K-nearest neighbor (KNN) algorithm, an effective machine learning technique for constructing anomaly detection models, semi-supervised classification models, and supervised classification models, was adopted to construct the anomaly detection model, semi-supervised classification model, and supervised classification model for detecting polymetallic anomalies in the case study in the Baishan area (China). The stream sediment survey data collected from the four 1:200,000 geological maps and the 30 polymetallic deposits found in the study area were used to train the KNN-based models for detecting polymetallic anomalies. The receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) were adopted to compare the performance of the KNN-based models in detecting polymetallic anomalies. The results show that the KNN-based semi-supervised and supervised classification models have similar performance in detecting polymetallic anomalies, and are superior to the KNN-based anomaly detection model. Therefore, as long as the training dataset is defined according to the known deposits in the study area, the KNN-based semi-supervised classification model and supervised classification model are potentially effective methods for detecting mineralization-related geochemical anomalies. [ABSTRACT FROM AUTHOR]

Cloud computing has now become the most effective platform for providing elastic and on-demand provisioning of high performance heterogeneous and homogeneous computing services basis on pay-per-use in the field high performance computing world. Task scheduling in cloud computing devotes researchers' attention to provide the optimal solution to this NP-Complete problem. An optimized task scheduling algorithm optimizes the cloud system's performance and generates the maximum profit for the cloud service provider. To overcome this issue in cloud computing, Authors developed a hybrid multi-faceted task scheduling algorithm in this research work. The proposed algorithm exploited the features of standard particle swarm optimization (PSO) and Ant Colony Optimization (ACO) technique. The PSO technique provides the best global optimal solution, whereas ACO offers the best local solution. To validate the results of the developed algorithm, performed a comparison of the makespan, cost, and resource utilization rate parameters against the well-known exiting four algorithms for the computer-generated tasks set in the cloud environment through a simulation experiment. The comparison results showed that the proposed algorithm reduces the makespan time and computation cost as well as increases resource utilization rate. [ABSTRACT FROM AUTHOR]

It is significant to investigate the coupling and coordination between agricultural carbon emission efficiency (ACEE) and food security and to achieve peak carbon dioxide emissions and carbon neutrality in agriculture as early as possible while ensuring national food security. The Super-SBM (slack-based model) and the comprehensive index method were used to measure the ACEE and food security level in Henan province from 2010 to 2020. The coupling coordination degree (CCD) and the relative state of ACEE and food security were analyzed using the coupling coordination degree model (CCDM) and the relative development degree model (RDDM). In addition, the interaction between ACEE and food security and the spatial–temporal heterogeneity were analyzed by combining with the geographically and temporally weighted regression (GTWR) model. The results showed that: Firstly, the overall level of ACEE was high, and the spatial heterogeneity of ACEE was significant. The spatial pattern of food security is relatively stable, with high levels in the south and low levels in the north. Secondly, The CCD between ACEE and food security in Henan province generally shows a decreasing trend. In the spatial dimension, the CCD between ACEE and food security in Henan province exhibits a spatial divergence characteristic of low in the center and high in the north and south, with significant regional variations. Finally, there is spatial and temporal heterogeneity between ACEE and food security. The regression coefficients differ significantly among different cities, the regression coefficients do not show a consistent positive or negative correlation, and the regression coefficients are distributed both positively and negatively. This study serves as a guide for achieving the goal of double carbon in agriculture and ensuring food security. [ABSTRACT FROM AUTHOR]

In situ 3-wt.% (Al3Zr/Al2O3 + ZrB2) particle-reinforced 6016Al-matrix composites were produced and squeezed at 650 °C. The effects of squeezing pressure (10–20 MPa) on the solidification microstructure and properties of the composites were investigated. Squeezed solidification of the 6016Al-matrix composites at 650 °C led to grain sizes of 65–70 µm. The synthesized (Al3Zr/Al2O3 + ZrB2) particles were segregated along the grain boundaries. Fine Mg-Si-rich Guinier–Preston zones or precipitates (~ 5 nm) were formed during solidification. Amorphous Al2O3 was observed adjacent to crystalline Al2O3 particles. The composites exhibited a lower yield strength (YS) of ~ 50 MPa because of the clustered porosity and agglomeration of reinforcement particles in hot spots (50–100 µm), formed during solidification. The composite squeezed under 20 MPa exhibited a superior ultimate tensile strength (UTS) of 186 MPa as compared to 170 MPa of the composite squeezed under 10 MPa. Mechanical properties of both the composites were improved upon hot rolling. Upon 80% thickness reduction by hot rolling, the composite squeezed under 10 MPa exhibited increase of ~ 300% in YS, ~ 30% in UTS, and 100% in fracture strain, while the composite squeezed under 20 MPa exhibited increase of ~ 260% in YS, ~ 6% in UTS, and ~ 32% in fracture strain. The improvements in properties originated from improved strengthening efficiency of (Al3Zr/Al2O3 + ZrB2) particles and homogenization of the microstructure. [ABSTRACT FROM AUTHOR]

A new method of how to use high concentrations of UV–Vis absorbable components in mobile phases for ion chromatographic separation of anions with indirect photometric detection (IPD) was developed. The UV–Vis absorption curves, the signal strengths at selected wavelengths, and the response ranges at different wavelengths of three organic salts, sodium benzoate, sodium 4-nitrobenzoate and sodium 3,5-dinitrobenzoate were detected using a photodiode array detector. Mobile phases containing these three organic salts at concentrations as high as 20 mM were used for ion chromatographic separations of inorganic anions, such as F−, Cl−, NO2−, Br−, NO3−, and SO42−. Separation characteristics detected at different wavelengths such as, the baseline stability, signal to noise levels shown as detection limits, linearity, etc., were investigated. It is found that the best wavelength used for IPD may not be the maximum or near the maximum absorption wavelength, but definitely not the non-absorptive wavelength of the eluent. Therefore, the best wavelength should be optimized. With the optimized wavelength at 385 nm, anions of sub-nanomoles were able to be quantitatively detected, and a good linear relationship with a correlation coefficients, (r > 0.9998), within the sample ranges from 0.5 to 200 ng was available. By using the optimized wavelength, the threshold of the detector will no longer be a strict restriction factor of using high concentrations of UV–Vis absorbable components. Consequently, columns with different ion exchange capacities can be used for separations with IPD. Furthermore, because the separation system can be fast re-equilibrated after sample injection using high concentrations of monovalent ion eluent, the separation efficiency can be highly improved. This method is promising for developing mobile phases for other chromatographic separations with IPD. [ABSTRACT FROM AUTHOR]

Cold rolling the CC AA 5754 aluminum alloy to different reductions was followed by an hour of annealing at 537 °C under varied pressures. The changes in microstructure and texture were studied. According to the findings, high-pressure heat treatment restricts recrystallization, and the restriction effect is stronger as pressure rises. The refining impact of high-pressure heat treatment can refine recrystallized grains, and it becomes stronger as the rolling reduction gets higher. The variation of recrystallization texture is significantly affected by high-pressure heat treatment. The sheet with a 19.6% reduction is found to have a weak cube texture at atmospheric pressure and 2 GPa, but the sheet that has been annealed at 4 GPa and 6 GPa has a strong cube texture and a weak β fiber rolling texture. High-pressure heat treatment improves the intensities of the cube and R textures in the fully recrystallized sheets with the same reduction. The strengthening impact of R texture from high-pressure heat treatment improves with increasing rolling reduction. [ABSTRACT FROM AUTHOR]

In this work, the finite-time synchronisation transmission of quantum signals between Jaynes-Cummings models is researched based on coupling technology. We first analyse the quantum properties of a Jaynes-Cummings model. Based on these, we achieve the finite-time synchronisation transmission of quantum signals between Jaynes-Cummings models and design the adaptive law of coupling coefficient. Finally, numerical simulations are given to demonstrate the effectiveness of the analytical results. [ABSTRACT FROM AUTHOR]

Soil acidification has become a major global issue, and it is important to study the causes and mechanisms of soil pH changes. This study detected soil pH changes in data collected from 1162 papers published during 1996–2000 and 2016–2020 in China, and it discussed the influencing factors on soil pH changes using Geodetector. The results showed that 58.4% of the collected data pairs were significantly acidified. Alfisols, desert soils, primarosols, semi-aqueous soils and aqueous soils were significantly acidified, while other types of soil did not change significantly. Soil pH on construction land decreased in units of 0.39 and on cultivated land decreased by 0.12, but soil pH changes in forest land and grassland were not significant. Nitrogen deposition, the amount of precipitation, sulphur deposition, temperature and vegetation planted in the soil had a great effect on soil acidification. This study provided a scientific reference for clarifying soil pH changes and made suggestions for subsequent soil remediation. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel sliding mode control technique for finite-time synchronization transmission of signal in erbium-doped laser network. First, we introduce the structure of erbium-doped laser network. Then the unique sliding surface and network controller are designed to complete the finite-time synchronization transmission of signal in erbium-doped laser network. Finally, the effectiveness of the finite-time synchronization transmission technique is numerically illustrated. [ABSTRACT FROM AUTHOR]

Al-xCu alloys (x = 5 wt.%, 15 wt.%, 33 wt.%, and 40 wt.%) were solidified at atmospheric pressure (AP) and at high pressure of 3 GPa (3 GPa). The microstructural evolution was studied, and it shows that the amount of eutectic Al2Cu phase is suppressed in the Al-xCu samples solidified under high pressure compared to the samples solidified under ambient conditions. In addition, the secondary dendritic arm spacing in the Al-15Cu and Al-33Cu alloy decreases when solidified under high pressure. The strain rate sensitivity (m) and activation volume (V*) were calculated from the nanoindentation experiments, and the results show that m increases while V* decreases for the hypoeutectic Al-5Cu and Al-15Cu alloys solidified at 3 GPa. Both m and V* decrease for the eutectic alloy (Al-33Cu), and for the hypereutectic composition (Al-40Cu), m decreases, whereas V* increases when solidified under high pressure. The results suggest that both the strength and plasticity for the hypoeutectic compositions increase simultaneously, while the plasticity decrease in the eutectic composition solidified under high pressure. On the other hand, for the hypereutectic Al-40Cu alloy solidified under 3 GPa, both the strength and plasticity decrease. [ABSTRACT FROM AUTHOR]

In this paper, based on semi-tensor product of matrices, a novel structure-preserving algorithm called L C structure-preserving algorithm is applied to quaternion Householder transformations for the first time. Then by means of the above contents, we present the L C structure-preserving methods for the QR decomposition and column pivoting QR decomposition of quaternion matrices, which make full use of high-level operations and relation of operations between quaternion matrices and their L C representation matrices. The numerical examples show that compared with the 'qr' of the Quaternion toolbox, the L C structure-preserving algorithm is more effective in calculating the QR decomposition of quaternion matrices. [ABSTRACT FROM AUTHOR]

Hypereutectic Al-20Si alloy is widely used in automotive, aerospace, and other fields because of its lightweight, high thermal conductivity, good wear, and corrosion resistance. In this study, the effects of powder characteristics and aging treatment on the corrosion behavior of Al-20Si alloy prepared by selective laser melting (SLM) were systematically investigated. The results showed that the Al-20Si alloy synthesized with ball-milled powders (BMPs) presents a large number of pores and coarse Si particles, while the Al-20Si alloy prepared with atomized powders (APs) shows a uniform and dense microstructure with relatively small grain sizes. The Si phase was continuously precipitated and coarsened with increased aging temperature. Moreover, the fibrous eutectic Si prepared with APs was transformed to a particulate shape. The alloy manufactured with APs shows excellent corrosion resistance. Meanwhile, with the increase of aging treatment temperature, the corrosion resistance of the alloy was significantly reduced. [ABSTRACT FROM AUTHOR]

In recent years, despite the rapid growth of cloud computing platforms, the technology confronts significant challenges including virtualization, load balancing, fault tolerance and most important of all, task scheduling. Considering the last challenge, because of high number of users and significant growth of number of tasks, there are some limitations such as MakeSpan, high resource utilization rate and executive costs in task scheduling algorithms. In this study, an effective method called HATMOG based on the smart hybrid of multiple criteria decision making algorithms of AHP-TOPSIS and Non-Dominated Sorting Genetic Algorithm (NSGAII) has been used to improve task scheduling in the cloud. The proposed method was done in two phases. In the first phase, the tasks which entered the cloud environment were placed in separate queues and then, according to task length, number of required processor elements and task expire time were sorted by AHP-TOPSIS algorithm in their priority queues. This phase helped on time assignment of more important tasks to the most appropriate virtual machines significantly that resulted in response time decrease and optimized resource utilization. In the second phase, the sorted tasks with prioritized queues were assigned to the appropriate virtual machines using NSGAII. Task assignment to virtual machine is an NP-Hard issue and NSGAII helped the efficiency improvement of cloud computing environment significantly because of the high convergence speed in finding close to optimal solution. The results of numerous simulations in Cloudism showed that the proposed method improved MakeSpan comparing TOPSIS-PSO, AHP-TOPSIS-PSO, NSGAII and PSO by 17.76, 155.73, 5.05 and 171.35 percent respectively and the average resource utilization by 15.94, 176.59, 4.83 and 176.65 percent respectively. [ABSTRACT FROM AUTHOR]

Aiming at the problems of poor hardenability and low mechanical strength of 45 steel after quenching and tempering at normal pressure, 45 steel was quenched and tempered under high pressure. The microstructure of 45 steel after high pressure quenching and tempering was analyzed by optical microscope, scanning electron microscope and transmission electron microscope, its hardness and compressive strength were tested by hardness tester and electronic universal testing machine, and compared with samples treated by the same process under atmospheric pressure. The results show that uniform and compact tempered sorbite can be obtained after high pressure quenching and tempering of 45 steel, and the precipitated granular carbides are finely dispersed, thus improving the mechanical properties of 45 steel. Under a pressure of 3 GPa, quenching at 900 °C for 15 min and 550 °C for 60 min tempering, the hardness and compressive yield strength of 45 steel were 36.3 HRC and 971 MPa, respectively, which were respectively 25.17% and 20.77% higher than the corresponding values obtained with the same process under atmospheric pressure quenching and tempering. This work provides a new method to effectively improve the mechanical properties of 45 steel. [ABSTRACT FROM AUTHOR]

The complete nucleotide sequence of a novel mycovirus, designated as "Rhizoctonia fumigata bipartite virus 1" (RfBV1), from Rhizoctonia fumigata AG-Ba isolate C-314 Baishi was determined. The genome of RfBV1 is composed of two double-stranded RNAs (dsRNA). dsRNA-1 (2311 bp) contains one open reading frame (ORF), which codes for the putative RNA-dependent RNA polymerase (RdRp) of the virus. dsRNA-2 (1690 bp) contains one ORF, which encodes a putative protein whose function is unknown. Phylogenetic analysis indicated that the RdRp of RfBV1 clustered with several unassigned bipartite viruses belonging to the CThTV-like viruses group, but not the family Amalgaviridae or Partitiviridae. Our study suggests that RfBV1 is a novel mycovirus related to the CThTV-like viruses. [ABSTRACT FROM AUTHOR]

In this report, the full genome sequence of a novel mycovirus, designated as "Rhizoctonia solani partitivirus SM03" (RsPV-SM03), was determined in Rhizoctonia solani AG-4 HG III isolate SM03. RsPV-SM03 genome consists of two dsRNAs (dsRNA-1 and dsRNA-2), each of them contains one single open reading frame (ORF). ORF1 of dsRNA-1 encodes a putative RNA-dependent RNA polymerase (RdRp), while ORF2 of dsRNA-2 encodes a putative viral coat protein (CP). Phylogenetic analysis indicated that the RdRp and CP of RsPV-SM03 are closely related to those of other members of the genus Alphapartitivirus, family Partitiviridae, suggesting that RsPV-SM03 represents a novel species in the genus Alphapartitivirus. [ABSTRACT FROM AUTHOR]

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Despite many studies on the influence of cropping practices on soil microbial community structure, little is known about ecological patterns of rare and abundant microbial communities in response to different tobacco cropping systems. Here, using the high-throughput sequencing technique, we investigated the impacts of two different cropping systems on soil biochemical properties and the microbial community composition of abundant and rare taxa and its driving factors in continuous and rotational tobacco cropping systems in the mountain lands of Yunnan, China. Our results showed that distinct co-occurrence patterns and driving forces for abundant and rare taxa across the different cropping systems. The abundant taxa were mainly constrained by stochastic processes in both cropping systems. In contrast, rare taxa in continuous cropping fields were mainly influenced by environmental perturbation (cropping practice), while governed by deterministic processes under rotational cropping. The α-diversity indices of rare taxa tended to be higher than those of the abundant ones in the two cropping systems. Furthermore, the network topologies of rare taxa were more complex than those of the abundant taxa in the two cropping systems. These results highlight that rare taxa rather than abundant ones play important roles in maintaining ecosystem diversity and sustaining the stability of ecosystem functions, especially in continuous cropping systems. [ABSTRACT FROM AUTHOR]

A large amount of fresh tobacco waste with high water content are produced in farmland, and it may cause environmental pollution if it is not properly treated. The fresh tobacco waste is not easily collected and transported, resulting in its centralized treatment is expensive. This study is to clarify whether it is feasible to treat fresh tobacco wastes by co-composting of them and soil in farmland and applied the obtained compost product into the soil instead of a part of tobacco-specific fertilizer. The results showed that, compared with that in original soil, the relative abundance of Pseudomonas, Azotobacter, and Coprinus of the co-composted products increased by roughly 244%, 323%, and 675%, respectively, and effective nitrogen and available potassium increased by roughly 157% and 132%, respectively. In addition, the nicotine content in co-composted products decreased dramatically compared with the discarded tobacco leaves. The application of the co-composted products and 20% fertilizer amount (15 g/plant) (YD5) exhibited the highest relative abundance of beneficial microbial communities in the soil and the best growth of tobacco plants. The co-composting of fresh tobacco waste and soil in farmland is an effective measure to treat the fresh tobacco waste, and its products increased beneficial microorganisms and stimulate the growth of tobacco plants by replacing an amount of the fertilizer. [ABSTRACT FROM AUTHOR]

With the rapid increase in the functionality of IoT applications, the services provided by edge/IoT devices have surged in the recent past. Fog computing is gaining momentum as a contemporary computational framework for IoT-enabled smart applications that offers a latency sensitivity advantage over cloud computing. Effective task scheduling reduces application computation and latency durations while improves QoS. Many researchers have proposed a variety of heuristic and metaheuristic approaches for effective scheduling; however, there is still scope for improvement. The present work proposes a hybrid of heuristic and metaheuristic techniques for the scheduling of tasks. fireworks algorithm (FWA) is a metaheuristic algorithm, and Heterogeneous Earliest Finish Time (HEFT) is a heuristic algorithm. The bi-objective optimization approach is presented to minimize the makespan and cost factors. To compare the performance of the algorithm, the experiments have been conducted on distinct and independent scientific workflows. The results of exhaustive simulations have established the significance of the presented BH-FWA algorithm over other comparative approaches. To validate the relevance of the technique for fog computing networks, the metrics utilized for comparisons are makespan, cost, and throughput. [ABSTRACT FROM AUTHOR]

Nicotine is a harmful pollutant mainly from the waste of tobacco factories. It is necessary to remove nicotine via high efficient strategies such as bioremediation. So far, an increasing number of nicotine degrading strains have been isolated. However, their degrading efficiency and tolerance to high content nicotine is still not high enough for application in real environment. Thus, the modification of nicotine metabolism pathway is obligated and requires comprehensive molecular insights into whole cell metabolism of nicotine degrading strains. Obviously, the development of multi-omics technology has accelerated the mechanism study on microbial degradation of nicotine and supplied more novel strategy of strains modification. So far, three pathways of nicotine degradation, pyridine pathway, pyrrolidine pathway, and the variant of pyridine and pyrrolidine pathway (VPP pathway), have been clearly identified in bacteria. Muti-omics analysis further revealed specific genome architecture, regulation mechanism, and specific genes or enzymes of three pathways, in different strains. Especially, muti-omics analysis revealed that functional modules coexisted in different genome loci and played additional roles on enhanced degradation efficiency in bacteria. Based on the above discovery, genomic editing strategy becomes more feasible to greatly improve bacterial degrading efficiency of nicotine. Key points: An increasing number of nicotine degrading strains have been isolated Multi-omics technology accelerates the mechanism study on microbial degradation of nicotine Genome editing strategy is potential for enhancement modification of nicotine-degrading strains [ABSTRACT FROM AUTHOR]

The history of plants to be utilized as medicines is thousands of years old. Black cumin is one of the most widely examined plant possessing naturally occurring compounds with antimicrobial potential. Foliar application of growth stimulators is a successful strategy to enhance yield and quality in many crops. A field study was planned to apply growth stimulator like moringa leaf extract on black cumin crop grown under field conditions using RCB design with three replications. All other agronomic inputs and practices were uniform. The treatments were moringa leaf extract concentrations (10%, 20%), growth stages (40 days after sowing, 80 DAS, 120 DAS, 40 + 80 DAS, 40 + 120 DAS, 80 + 120 DAS, 40 + 80 + 120 days after sowing) and two controls unsprayed check (i.e. no moringa leaf extract, no water) and sprayed check (no moringa leaf extract + water). Application of 20% moringa leaf extract at stage-7 (40 + 80 + 120 days after sowing) had significantly increased plant height, branches plant−1, essential oil content, fixed oil content, peroxidase value and iodine value of black cumin oil over unsprayed control. Application of moringa leaf extract showed maximum results and improves growth and yield of black cumin when applied at 40 + 80 + 120 days after sowing. As this study was only conducted using moringa leaf extract, it is advisable to conduct an experiment with various bio stimulants along with fertilizer combinations and growth regulators to check their synergistic effects for more reliable and acceptable recommendations in future. [ABSTRACT FROM AUTHOR]

Maize is a low-temperature (LT)-sensitive plant and its physiological responses towards LT of temperate regions developed is an adaptive trait. To further our understanding about the response of maize to LT at the physiological and photosynthesis level, we conducted Infrared Gas Analysis (IRGA using LICOR6400-XT in 45-day-old grown two maize genotypes, one from temperate region (Gurez-Kashmir Himalayas), viz., Gurez local (Gz local), and another from tropics (Gujarat), viz., GM6. This study was carried out to evaluate the underlying physiological mechanisms in the two differentially temperature-tolerant maize genotypes. Net photosynthetic rate (A/PN), 18.253 in Gz local and 25.587 (µmol CO2 m−2 s−1) in GM6; leaf conductance (gs), 0.0102 in Gz local and 0.0566 (mmol H2O m−2 s−1) in GM6; transpiration rate (E), 0.5371 in Gz local and 2.9409 (mmol H2O m−2 s−1) in GM6; and water use efficiency (WUE), 33.9852 in Gz local and 8.7224 (µmol CO2 mmol H2O−1) in GM6, were recorded under ambient conditions. Also, photochemical efficiency of photosystem II (PSII) (Fv/Fm), 0.675 in Gz local and 0.705 in GM6; maximum photochemical efficiency (Fv′/Fm′), 0.310234 in Gz local and 0.401391 in GM6; photochemical quenching (qP), 0.2375 in Gz local and 0.2609 in GM6; non-photochemical quenching (NPQ), 2.0036 in Gz local and 1.1686 in GM6; effective yield of PSII (ФPSII), 0.0789 in Gz local and 0.099 in GM6; and electron transport rate (ETR), 55.3152 in Gz local and 68.112 in GM6, were also evaluated in addition to various response curves, like light intensities and temperature. We observed that light response curves show the saturation light intensity requirement of 1600 µmol for both the genotypes, whereas temperature response curves showed the optimum temperature requirement for Gz local as 20 °C and for GM6 it was found to be 35 °C. The results obtained for each individual parameter and other correlational studies indicate that IRGA forms a promising route for quick and reliable screening of various stress-tolerant valuable genotypes, forming the first study of its kind. [ABSTRACT FROM AUTHOR]

A novel Mg alloys of Mg–xZn–ySb (x = 0, 2, 4, 6; y = 0, 0.2, 0.5, 0.8, 1.2) were designed and their microstructure, thermal conductivity and mechanical properties were systematically investigated in the present study. The as-cast Mg–Zn–Sb ternary alloys consist of α-Mg, Mg4Zn7 and Mg3Sb2 phases. Sb addition can refine the eutectic structure (α-Mg + Mg4Zn7) by the growth of Mg4Zn7 on Mg3Sb2 phases. The thermal conductivity of Mg–Zn–Sb alloys decreased with increasing Sb content. There existed an interactive effect of Zn/Sb on the thermal conductivity of the Mg–Zn–Sb alloys. The negative effect of Sb addition on thermal conductivity of alloys was getting smaller with increasing Zn content in alloys. The negative effect of Mg3Sb2 phases on the thermal conductivity of alloys could be weakened by the formation of weak-scattering Mg4Zn7 coated on Mg3Sb2 phases. The best refinement effect on microstructure could be obtained with 0.8 wt%Sb addition. Mg–4Zn–0.8Sb alloy possess the best comprehensive properties with thermal conductivity of over than 120 W/(m·K) and UTS of 185.6 MPa. [ABSTRACT FROM AUTHOR]

The microstructure, room temperature and 650 °C tensile properties of an (α + β) titanium alloy were investigated after aging over a temperature range of 600–750 °C following solution treatment. The results exhibit that both aging temperature and aging time influence the precipitation behavior of α2 phase, and the size of α2 phase affects the tensile properties. The growth speed of α2 phase gets quicker with the aging temperature increasing under the same aging time. For a given aging temperature, the size of α2 phase gets larger when prolonging the aging time. There are significant improvements in yield and ultimate tensile strength at room temperature and 650 °C after aging at 600 °C for 2 h, but these values decrease with the size of α2 phase increasing. It is found that α2 phase, less than 7 nm, does not impair the room-temperature ductility. However, when the size of α2 phase grows up from 7 to 15 nm, ductility decreases drastically. During 650 °C tensile process, with the particle size increasing from 3 to 15 nm, the interaction between moving dislocations and coherent particles changes from cutting mechanism to bypass mechanism. With the α2 particle size increasing from 3 to 15 nm, the interaction between moving dislocations and coherent particles changes from cutting mechanism to bypass mechanism at 650 °C, and 6 nm is in the range of critical radius, which corresponds to the maximum strengthening effect of α2 phase at 650 °C [ABSTRACT FROM AUTHOR]

In this article, the finite time (FT) synchronization problem of fractional order quaternion valued neural networks with time delay is investigated. Without separating the quaternion valued system into two complex valued or four real valued systems, the FT synchronization conditions are derived through using Lyapunov direct method. Furthermore, the setting time is estimated, which is influenced by the order of fractional derivative and control parameters. Finally, numerical simulations are shown to verify the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Long-term frequent tillage would cause black soil degradation and serious soil erosion as soil microbial communities and soil structure are extremely sensitive to tillage process. However, there is no unified conclusion on the relationship between the distribution of soil water-stable aggregates (WSAs), and microbial community construction and diversity under long-term tillage in black soil during different seasons. In this study, we used wet-sieving method to evaluate the composition and stability of soil WSAs and employed Illumina MiSeq high-throughput sequencing technology to study the diversity, taxonomic composition and co-occurrence network properties of microbial community, comparing outcomes between uncultivated soil and long-term cultivated soil for 60 years in Keshan farm of Heilongjiang Province. The results showed that after long-term tillage, the proportion of larger than 1 mm WSAs reduced by 34.17–51.37%, and the stability of WSAs, soil pH, organic matter (OM), total nitrogen (TN) contents decreased significantly in all seasons (P < 0.05), while soil available phosphorus (AP) and available potassium (AK) contents increased remarkably (P < 0.05). The diversity of bacteria increased, while that of fungi decreased. Soil fungal communities were more susceptible to long-term tillage than bacterial and archaeal communities. Actinobacteria mainly exist in large WSAs (˃1 mm), and when their relative abundance is high, it is beneficial to improve the water-stability of black soil; while Proteobacteria and Gemmatimonadetes may exist in small WSAs (˂1 mm), whose high relative abundance will weaken the water-stability of black soil. The experimental results provide a scientific theoretical basis for sustainable utilization of black soil. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) is highly sensitive to drought stress, resulting in large losses in yield; therefore, strategies aimed at enhancing drought tolerance are essential. Melatonin improves stress tolerance in plants; however, its mechanism in maize seedlings under drought stress remains unknown. Therefore, we investigated the effects of foliar-sprayed melatonin (100 umol L−1) on the antioxidant system, photosynthetic gas exchange parameters, stomatal behavior, endogenous melatonin and abscisic acid (ABA)-related gene expression in maize seedling leaves under 20% polyethylene glycol (PEG)-induced drought stress. PEG treatment resulted in oxidative stress and stomatal closure, resulting in chlorophyll degradation and inhibition of photosynthesis; thereby, reducing seedling biomass. Melatonin pretreatment significantly improved the relative water content, photosynthetic gas exchange parameters and stomatal behavior; thereby, maintaining chlorophyll contents and photosynthesis. Melatonin also stimulated the antioxidant system, enhancing the clearance of reactive-oxygen species, preventing severe damage under PEG-induced drought. Pre-treatment also increased endogenous melatonin and inhibited up-regulation of NCED1, an ABA synthesis-related gene, as well as selectively up-regulating ABA catabolic genes ABA8ox1 and ABA8ox3, reducing ABA accumulation and inducing stomatal reopening. Overall, these findings suggest that melatonin pre-treatment alleviated the inhibitory effects of drought stress on photosynthesis, enhancing tolerance in maize seedlings. [ABSTRACT FROM AUTHOR]

We analyze the specific features of the structure and elastic characteristics of powder titanium-matrix composites reinforced with titanium carbide and titanium boride. The difference between the characters of dependence of the modulus of elasticity on the content of high-modulus component is analyzed for sintered and hot-forged composites. It is discovered that the modulus of sintered materials is determined both by the content of reinforcing admixtures and by the porosity of the alloy. At the same time, for hot-forged specimens, the modulus monotonically increases with the content of the high-modulus components. It is shown that, for sintered composites of all compositions and for hot-forged composites reinforced by titanium carbide, anisotropy is practically absent, whereas for hot-forged composites reinforced by titanium boride, an insignificant (up to 10%) anisotropy of the structure and elastic characteristics is caused by the reorientation of acicular titanium monoboride particles in the direction perpendicular to the direction of application of the active force in course of hot forging. [ABSTRACT FROM AUTHOR]

Anthropogenic activities in the past and present eras have created global warming and consequently a storm of drought stress, affecting both plants and animals. Being sessile, plants are more vulnerable to drought stress and consequently reduce plant growth and yield. To mitigate the effects of drought stress on plants, it is very crucial to determine the plant response mechanisms against drought stress. Drought response mechanism includes morph-physiological, biochemical, cellular and molecular processes takes place in plants underlying drought stress. These processes include improvement in root system, leaf structure, osmotic adjustment, relative water content and stomata regulation. In addition, calcium and phytohormone (Abscisic acid, Jasmonic acid, Salicylic acid, Auxins, Gibberellins, Ethylene etc.) signaling pathways and scavenging of reactive oxygen species are the key mechanisms to cope with drought stress. Moreover, microorganisms such as bacteria and fungi also have an important role in drought tolerance enhancement. To further elucidate and improve drought tolerance in plants, quantitative trait loci, transgenic approach and application of exogenous substances (nitric oxide, 24-epibrassinoide, glycine betaine and proline) are very crucial. Hereby, the present study integrates various mechanisms of drought tolerance in plants. [ABSTRACT FROM AUTHOR]

Key message: This study shows mitigating effects achieved by exogenously applied melatonin in drought-stressed Davidia involucrata seedlings and demonstrates the reprogramming of gene networks related to melatonin-mediated drought stress response. Drought stress can have adverse effects on endangered plant species such as the dove tree (Davidia involucrata Baill.). Despite significant advances in uncovering the roles of melatonin in abiotic stress tolerance, the function of melatonin in the dove tree during drought stress is unknown. Here, we show the effects of exogenously applied melatonin on drought damage to D. involucrata seedlings. Melatonin pretreatment of dove tree seedlings was correlated with reduced membrane lipid peroxidation, suppressed production of drought-induced reactive oxygen species (ROS), and improved antioxidant capacity. Comparative RNA-Seq-based transcriptome profiling was employed to dissect the mechanistic basis of melatonin in drought response. We found that melatonin pretreatment resulted in differential expression of 2737 genes (1849 up-regulated and 888 down-regulated) under drought stress. Further detailed analysis suggested that melatonin modulates D. involucrata response to drought through fine-tuning of multiple phytohormone signaling and synthesis pathways, including transcriptional stimulation of auxin signaling-related genes and brassinosteroid biosynthetic genes. Moreover, phenylpropanoid biosynthesis and glutathione metabolism pathways were activated by melatonin, which could be linked to the observed enhancement of ROS scavenging capacity in melatonin-pretreated D. involucrata seedlings under drought condition. Additionally, melatonin-mediated drought stress response may involve activation of calcium signaling via up-regulating gene expressions of CNGC, CaM/CML, and CDPK family members. Collectively, this study yields insights into transcriptionally regulatory mechanisms of melatonin action under drought stress and provides a potential strategy for ex situ cultivation and landscape application of endangered ornamental tree species particularly in the context of global climate change. [ABSTRACT FROM AUTHOR]

Brassinosteroids (BR) play diverse roles in the regulation of plant growth and development. BR promotes plant growth by triggering cell division and expansion. However, the effect of exogenous BR application on the leaf size and expansion of tobacco is unknown. Tobacco seedlings are treated with different concentrations of exogenous 2,4-epibrassinolide (EBL) [control (CK, 0 mol L−1), T1 (0.5 × 10−7 mol L−1), and T2 (0.5 × 10−4 mol L−1)]. The results show that T1 has 17.29% and T2 has 25.99% more leaf area than control. The epidermal cell area is increased by 24.40% and 17.13% while the number of epidermal cells is 7.06% and 21.06% higher in T1 and T2, respectively, relative to control. So the exogenous EBL application improves the leaf area by increasing cell numbers and cell area. The endogenous BR (7.5 times and 68.4 times), auxin (IAA) (4.03% and 25.29%), and gibberellin (GA3) contents (84.42% and 91.76%) are higher in T1 and T2, respectively, in comparison with control. Additionally, NtBRI1, NtBIN2, and NtBES1 are upregulated showing that the brassinosteroid signaling pathway is activated. Furthermore, the expression of the key biosynthesis-related genes of BR (NtDWF4), IAA (NtYUCCA6), and GA3 (NtGA3ox-2) are all upregulated under EBL application. Finally, the exogenous EBL application also upregulated the expression of cell growth-related genes (NtCYCD3;1, NtARGOS, NtGRF5, NtGRF8, and NtXTH). The results reveal that the EBL application increases the leaf size and expansion by promoting the cell expansion and division through higher BR, IAA, and GA3 contents along with the upregulation of cell growth-related genes. The results of the study provide a scientific basis for the effect of EBL on tobacco leaf growth at morphological, anatomical, biochemical, and molecular levels. [ABSTRACT FROM AUTHOR]