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PurposeThis research presents a framework that allows project managers to predict the next critical paths (CP(s)) and to take extra care when planning and executing those activities that have the potential to cause changes in a project's current CP(s).Design/methodology/approachThe method presented here is based on an assessment of each activity's contribution to the overall schedule variance, which involves assigning a probability distribution function to each activity duration in the project. A sensitivity analysis is also carried out, which forms the basis of identifying which activity most affects the project completion date and therefore will have the greatest effect in changing the CP.FindingsThe authors’ analysis reveals that the most appropriate probability density function (PDF) for the targeted project is the normal distribution. However, the aim of this work is not to determine the most suitable distribution for each activity but rather to study the effect of the activity distribution type on the CP prediction. The results show that the selection of the appropriate probability distribution is very important, since it can impact the CP prediction and estimated project completion date.Originality/valueThis research work proposes a delay analysis scheme which can help the project manager to predict the next CP and to improve performance by identifying which activity is the bottleneck. On the other hand, the simplicity arises from the fact that this method does not require any expensive machines or software to generate results.

Comprehensive understanding of physiological and biochemical principles of tolerance to salt can lead to successful breeding of crop varieties tolerant to salt stress. To examine the content of ade...

Al7075/B4C surface composites were fabricated by friction stir processing using four passes. The B4C powders were added into the prepared grooves with 1 and 2 mm width at the surface of Al7075 alloy in two different manners. In the first one, the B4C powders were added prior to the four consecutive passes in one stage. In the second manner, the powders were added in two stages, prior to the first pass and following the second one. The microstructural evaluations showed that the increase in the volume fraction of reinforcement significantly reduced the matrix grain size. Meanwhile, the reinforcement had a more homogeneous and uniform distribution in the samples processed through four consecutive passes. The maximum hardness and wear resistance was achieved in the one-stage powder-added samples, containing higher volume fraction of the reinforcement. A direct relationship was observed between the wear resistance and the composite layer hardness. The wear mechanism in the Al7075 substrate and the non-reinforced friction stir processed sample was the delamination of unstable aluminum oxide tribolayer. However, in the composite samples, a mechanically mixed layer, containing aluminum, chromium, and iron mixed oxides was formed along with B4C on the worn surface. In the two-stage powder-added samples, containing lower amounts of reinforcement, the detachment of mechanically mixed layer resulted in three-body abrasive wear condition and high friction coefficient. However, the most stable mechanically mixed layer was formed on the surface of the one-stage powder-added sample containing higher amounts of B4C.

The optical properties of NH2-UiO-66 as a visible light-active metal organic framework was further enhanced through the diazotization reaction with π-conjugated 1-naphthol reagent. Diffuse reflectance UV-Vis spectrum of diazotized MOF, named as Azo-UiO-66, exhibited a significant red shift compared to unfunctionalized NH2-UiO-66 due to the formation of diazo compound. Also, Tauc calculations indicated considerable decrease in band gap energy from 2.68 to 1.7 eV, resulted in improvement of visible light harvesting. Furthermore, other physicochemical techniques e.g. X-ray diffraction (XRD), N2 adsorption-desorption analysis, thermogravimetric analysis (TGA), energy dispersive X-ray (EDX), and CHN elemental analyses demonstrated the successful MOF diazotization with 1-naphthol and preservation of NH2-UiO-66 framework upon post modification process. The reduction of hexavalent chromium, Cr(VI), as a serious contaminant in wastewater to less toxic Cr(III) was performed over prepared photocatalyst, which demonstrated the positive role of ligand functionalization and enhancement of visible light absorption on overall photocatalytic performance of Azo-UiO-66.

The optical properties of NH

Leaf or brown rust caused by Puccinia triticina Eriks. (Pt) is a major biotic constraint threatening bread wheat production worldwide. The continued evolution of new races of Pt necessitates a constant search for the identification of new resistance genes, or QTLs, to enhance the resistance durability of bread varieties. On a panel of 320 bread wheat accessions, we used a genome-wide association study (GWAS) technique to map loci associated with Pt resistance using single-nucleotide polymorphism markers (SNPs) generated by genotyping-by-sequencing (GBS). The panel was tested with five Pt races gathered from different regions of IRAN to identify loci associated with seedling resistance. After estimating genetic relatedness and population structure among accessions, GWAS discovered a total of 19 SNPs on chromosomes 1B, 2B, 3A, 3B, 4A, 5B, 5D, 6A, 6B, 6D, 7B, and 7D that were significantly associated with seedling stage resistance. The three SNP markers rs12954, rs34220, and rs42447 on chromosomes 5D, 6A, and 7D, respectively, associated with resistance to Pt race PKTTS expressing potential new loci for leaf rust resistance. Overall, this research gives an integrated perspective of leaf rust resistance resources in Iranian bread wheat and recognizes new resistance loci that will be valuable to expand the set of resistance genes available to control this serious disease.

COVID-19, one of the greatest health challenges of the present century, has infected millions of people and caused more than 6 million deaths worldwide. The causative agent of this disease is the new virus SARS-CoV-2; which continues to spread globally and sometimes with new and more complex aspects than before. The present study is an observational study aimed to investigate the role of AQI; PM

Three new mixed-ligand copper(II) complexes (

A tandem reaction of 2-alkynylbenzaldoximes with propargylic alcohols has been developed for the synthesis of α-(4-bromo-isoquinolin-1-yl)-propenones. Employing 2-alkynylbenzaldoximes as a precursor in the presence of Br

Benzene, toluene, ethylbenzene, and xylene, known as BTEX, adversely affect human health. This study aimed to measure BTEX concentration and assess the health risk through inhalation exposure to these compounds in a municipal wastewater treatment plant. The ambient air samples were collected using the active sampling method in summer and winter. Sampling sites were close to wastewater treatment units, including bar screen & grit chamber (Site-1), aeration tank & secondary clarifiers (Site-2), anaerobic sludge digester (Site-3), and office & control building (Site-4). Results indicate that the mean levels of benzene and toluene in winter were higher than in summer. The levels of benzene and toluene were below the occupational exposure levels of the American Conference of Governmental Industrial Hygienists (ACGIH) and Occupational Safety and Health Administration (OSHA). The carcinogenic risk (CR) and hazard quotient (HQ) were assessed using the United States Environmental Protection Agency (U.S.EPA) method, and Monte Carlo simulation (MCS) was applied to quantify the uncertainty and sensitivity analysis. The CRs for all sampling sites were below the U.S.EPA threshold limit (1.0 × 10−4). The HQ values for benzene nearby Site-2 were above 1.0, indicating inhalation exposure could pose a health hazard. Besides, the HQ results for exposure to toluene in all sampling sites were less than 1.0. The sensitivity analysis had shown that the risk determinant for carcinogenic and non-carcinogenic risk was exposure time, followed by concentration.

Bibliographic properties of more than 75 million scholarly articles, are examined and trends in overall research productivity are analysed as a function of research field (over the period of 1970–2020) and author gender (over the period of 2006–2020). Potential disruptive effects of the Covid-19 pandemic are also investigated. Over the last decade (2010–2020), the annual number of publications have invariably increased every year with the largest relative increase in a single year happening in 2019 (more than 6% relative growth). But this momentum was interrupted in 2020. Trends show that Environmental Sciences and Engineering Environmental have been the fastest growing research fields. The disruption in patterns of scholarly publication due to the Covid-19 pandemic was unevenly distributed across fields, with Computer Science, Engineering and Social Science enduring the most notable declines. The overall trends of male and female productivity indicate that, in terms of absolute number of publications, the gender gap does not seem to be closing in any country. The trends in absolute gap between male and female authors is either parallel (e.g., Canada, Australia, England, USA) or widening (e.g., majority of countries, particularly Middle Eastern countries). In terms of the ratio of female to male productivity, however, the gap is narrowing almost invariably, though at markedly different rates across countries. While some countries are nearing a ratio of .7 and are well on track for a 0.9 female to male productivity ratio, our estimates show that certain countries (particularly across the Middle East) will not reach such targets within the next 100 years. Without interventional policies, a significant gap will continue to exist in such countries. The decrease or increase in research productivity during the first year of the pandemic, in contrast to trends established before 2020, was generally parallel for male and female authors. There has been no substantial gender difference in the disruption due to the pandemic. However, opposite trends were found in a few cases. It was observed that, in some countries (e.g., The Netherlands, The United States and Germany), male productivity has been more negatively affected by the pandemic. Overall, female research productivity seems to have been more resilient to the disruptive effect of Covid-19 pandemic, although the momentum of female researchers has been negatively affected in a comparable manner to that of males.

Two new mixed-ligand complexes with general formula [Cu(SB)(L')]ClO

Practical Pd-catalyzed 2-pyridones were designed to achieve chromeno[2,3

The present paper proposes a six-FinFET two-memcapacitor (6T2MC) non-volatile static random-access memory (NVSRAM). In this design, the two memcapacitors are used as non-volatile memory elements. The proposed cell is flexible against data loss when turned off and offers significant improvement in read and write operations compared to previous NVSRAMs. The performance of the new NVSRAM design is evaluated in terms of read and write operation at particular nanometric feature sizes. Moreover, the proposed 6T2MC cell is compared with 8T2R, 8T1R, 7T1R, and 7T2R cells. The results show that 6T2MC has a 5.50% lower write delay and 98.35% lower read delay compared to 7T2R and 7T1R cells, respectively. The 6T2MC cell exhibits 38.86% lower power consumption and 23.80% lower leakage power than 7T2R and 7T1R cells. The proposed cell is significantly improved in terms of HSNM, RSNM, and WSNM compared to 8T2R, 8T1R, 7T2R, and 7T1R cells, respectively. Important cell parameters, such as power consumption, data read/write delay, and SNM, are significantly improved. The superior characteristics of FinFET over MOSFET and the combination of this technology with memcapacitors lead to significant improvement in the proposed design.

Background: Environmental stresses are the most important factors limiting crops production in worldwide. Tocopherol, belonging to family of vitamin E compounds, is an amphipathic antioxidants involved in oxidative responses. In the current study, we generated transgenic canola plants overexpressing Arabidopsis VTE1 gene (At.TC) through Agrobacterium tumefaciens system. Methods and results: The putative transgenic plants were successfully regenerated and acclimated in greenhouse conditions. The transcriptional activity of the At.TC gene was evaluated by RT-PCR. In addition, the relative gene expression analysis by qRT-PCR confirmed an increased expression pattern of the transformed gene in canola transgenic lines, with the highest level in R. Line1. Given the results, the transgenic plants, particularly H. Line1 and R. Line2 showed a lower lipid peroxidation compared to WTs under FC 30%. Moreover, two ROS scavenging enzymes including CAT and PPO were up-regulated in transgenic lines; however, no significant pattern was observed for Ascorbate Peroxidase. Also, the amount of leaf tocopherol was significantly more in all T1 lines under drought stress (FC 30%). Conclusion: Taken together, here we successfully developed transgenic lines overexpressing At.TC gene constituently throughout the plant. The results confirmed that the generated transgenic plants are resistant to drought stress, thereby paving the way toward introducing canola plants to deal with the climate change and water shortage.

Here, the carboxamide ligand N-(thiazole-2-yl) picolinamide (L) was synthesized in an ionic liquid tetrabutylammonium bromide (TBAB) as the benign reaction medium. The sensitivity of L towards different metal-ions was investigated, and a comprehensive, logical optical investigation was conducted for the IIB transition metal ions, Hg2+, Cd2+ and Zn2+, based on off–on switch sensor protocols. In the absence of these metal ions, L showed weak emission only, but fluorescence intensity increased considerably upon their addition to a sensitivity range of 10−6 M. This phenomenon was enhanced significantly in the presence of Zn2+ compared to other metal ions, likely due to the coordination of metallic ions to the L, which led to the chelation-enhanced fluorescence (CHEF) effect. To prove these results, several characterization studies were conducted: a single crystal from the metal–ligand complex was prepared, followed by conduction of X-ray single crystal analysis from the Zn-complex (2) and Cd-complex (3), and conducting spectral analysis from the Zn2+, Hg2+ and Cd2+ complexes. These complexes and also the ligand showed very low toxicity on the PC12 cell line suggesting their promise for a wide range of future medical applications.

The Science of Science is an emerging field that enables tracking the dynamics of science in the form of birth and death of scientific fields and research trends in them. This study proposes a framework to analyze the content of academic publications to extract research trends and explore their temporal evolution. In this proposed framework, state-of-the-art embedding techniques are reviewed and utilized to consider semantic vectors of publications’ keywords, which have been used to produce semantic-based clusters reflecting research trends or sub-fields. We compare our proposed method with LDA, as a baseline method, to demonstrate the explainability of the clusters, applying them to the field of "Artificial Intelligence" (AI) as a case study.

Unlike the past studies targeting overall mobility patterns, we examined a wide range of probability density functions among which Weibull found to better explain the human mobility rather than the...

The zwitterionic intermediates, generated in situ from Ph3P and dialkyl acetylenedicarboxylates, are trapped by N–H acidic 2-(alkylamino)-2-(1,3-dioxo-1H-inden-2(3H)-ylidene)acetonitriles in refluxing toluene to afford dialkyl 2-alkyl-1-cyano-9-oxo-3,9-dihydro-2H-indeno[2,1-c]pyridine-3,4-dicarboxylates in good yields. The structure of a typical product was confirmed by X-ray crystallography.

The successful synthesis of novel spirofused spiropyrrolidine 1,3-indanedione derivatives using 1,3-dipolar cycloaddition reactions is reported. 1-Benzyl-3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones prepared via Knoevenagel condensation of 1-benzyl-4-piperidinone with aromatic aldehydes underwent a one-pot, three-component reaction with benzylamines and ninhydrin in ethanol to afford the desired products.

In today’s competitive marketplace demand, evaluation and selection of suppliers are pivotal for firms, and therefore decision makers need to select suppliers and the optimal order quantities when outsourcing. However, there is uncertainty and risk due to lack of precise data for supplier selection. Uncertainty can impose shortage or overstocks, because of stochastic demand, to firms; in this case, considering inventory control is essential. In this research, an appropriate spatial model is developed for a multi-product supplier selection model with service level and budget constraints. Learning Vector Quantization Neural Network is used to find the optimal number of decision variables with the goal of maximizing the expected profit of supply chains. By analyzing a practical example and conducting sensitivity analysis, we find that corporate profit will be maximized if the optimal integration of suppliers and the optimal order quantities from each supplier is determined. In addition, budget and service level should be considered in the process of finding the best result.

Copper-based coordination polymers, Cu2(μ2-MeCO2)4(DABCO) (1), [Cu(1,4-BDC-Br)(DABCO)0.5]. xDMF.yH2O (2) and Cu(1,4-BDC-OH)(DMF) (3) (1,4-BDC-Br = 2-bromoterephthalate, DABCO = triethylenediamine, 1,4-BDC-OH = 2-hydroxyterephthalate) were solvothermally synthesized. Two polymorphs of 1 (1a and 1b) were obtained which both contain 1-D chains with similar connectivity and different packing. Compound 2 is a 3-D metal-organic framework (MOF) and 3 exhibits a 2-D structure. Structural analyses of the coordination polymers showed that they all have similar paddle-wheel secondary building units (SBUs). The coordination polymers 1–3 were characterized by FT-IR, thermogravimetric analysis (TGA), powder X-ray diffraction (XRD) and atomic absorption spectroscopy. Compound 2 is further analyzed by nitrogen adsorption/desorption technique. The obtained coordination compounds were employed as heterogeneous catalysts for selective oxidation of benzyl alcohol to benzoic acid using CH2Cl2 as solvent and tert-butyl hydroperoxide (TBHP) as oxidant. The catalysts displayed good activity in the oxidation reaction and could be reused without noticeable loss of activity.

Purpose The purpose of this paper is to introduce a new design for a finger and wrist rehabilitation robot. Furthermore, a fuzzy sliding mode controller has been designed to control the system. Design/methodology/approach Following an introduction regarding the hand rehabilitation, this paper discusses the conceptual and detailed design of a novel wrist and finger rehabilitation robot. The robot provides the possibility of rehabilitating each phalanx individually which is very important in the finger rehabilitation process. Moreover, due to the model uncertainties, disturbances and chattering in the system, a fuzzy sliding mode controller design method is proposed for the robot. Findings With the novel design for moving the DOFs of the system, the rehabilitation for the wrist and all phalanges of fingers is done with only two actuators which are combined in one device. These features make the system a good choice for home rehabilitation. To control the robot, a fuzzy sliding mode controller has been designed for the system. The fuzzy controller does not affect the coefficient of the sliding mode controller and uses the overall error of the system to make a control signal. Thus, the dependence of the controller to the model decreases and the system is more robust. The stability of the system is proved by the Lyapunov theorem. Originality/value The paper provides a novel design of a hand rehabilitation robot and a controller which is used to compensate the effects of the uncertain parameters and chattering phenomenon.

Bronze/TiO2 composites with 5 wt.% and 20 wt.% TiO2 were prepared by mechanical milling and densification of the corresponding powder mixtures. The milled powders were densified by two different methods. In the first process, the powders were pressureless sintered in liquid state at three different temperatures. The observations showed that just the samples with 5 wt.% TiO2 which were sintered at 900°C were densified by liquid phase sintering and the other samples were not consolidated via the applied sintering conditions. The sintered compacts were cold-repressed for more densification under 100 MPa. In the second method, the milled powders were consolidated via spark plasma sintering without any prepressing process. The microstructural evaluations showed a fine dispersion of TiO2 within the bronze matrix of the spark plasma sintered samples. The highest relative density (96%), hardness (320 Vickers) and flexural strength (365 MPa) corresponded to the spark plasma sintered sample with 20 wt.% TiO2.

The effects of nickel addition on the microstructure and phase formation in the magnesium-silicon alloy were studied. Besides the primary and eutectic in-situ formed Mg2Si phase in the Mg Si alloys, a new intermetallic phase was identified in the Ni-containing alloys. Based on energy-dispersive spectroscopy (EDS) and X-ray diffraction analyses, it was shown that this phase contains Mg, Ni, and Si elements, which contradicts the presence of the expected Mg2Ni phase. Through rigorous EDS analysis, the new in-situ formed phase was identified as (Mg,Ni)3Si or more accurately as Mg8Ni7Si5 intermetallic compound, called χ-phase, which has not been reported so far in the Mg Si Ni ternary space. Finally, the properties of the studied Mg Si Ni alloys were also briefly discussed.

Three new alkaline earth metal–organic frameworks (MOFs), [Mg2(BDC-OH)2(DMF)3] (Mg-HBDC), [Ca(BDC-OH)(DMF)2] (Ca-HBDC), and [Sr(BDC-OH)(DMF)] (Sr-HBDC) (BDC-OH = 2-hydroxyterephthalate(2−) anion and DMF = N,N-dimethylformamide), were synthesized by the assembly of BDC-OH and nitrate salts of the metal ions under solvothermal conditions. Single-crystal structure analysis revealed that Ca-HBDC and Sr-HBDC are isostructural to their corresponding MOFs containing 2,5-dihydroxyterephthalalate(2−) anion (H2dhtp) and terephthalate(2−) anion (BDC), respectively. The MOFs were also characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and powder X-ray diffraction. The obtained MOFs were applied as heterogeneous basic catalysts for the Knoevenagel condensation reaction at room temperature. The catalysts showed good catalytic activity and structural stability in the condensation reaction and could be reused without observable loss of activity.

This research aims to investigate whether multi/inter-disciplinary research activities are related to research impact and publication counts of scholars. Since researchers with very high levels of multi/inter-disciplinarity might be able to target complex problems, we would expect them to receive more credits than their colleagues with a stronger disciplinary orientation. We analysed Web of Science (WoS) indexed publications of all associate and full professors from a random sample of Australian universities in physics, chemistry and biology (1980–2014). Australian Fields of Research (FoR) codes assigned to journals were used to calculate the diversification of authors’ publications. The number of citations in the first 3 years, number of 10% most frequently cited papers, and citation impact percentile were used for impact assessment. A few indicators were used to measure the diversity including ‘extent of diversification (ED)’ (number of distinct FoR codes divided by the number of publications) and ‘diversification ratio (DR)’ (ratio of the publications falling outside the dominant code to the total number of publications). A total of 47.76% of biologists’ publications, 35.23% of physicists’ publications and 20.36% of chemists’ publications were published in journals assigned to fields other than the Australian associate and full professors’ fields. Publications from biologists had the largest values of diversification. Women (compared with men) and associate professors (compared with full professors) in chemistry, biology and overall were more probably to publish diversely. ED was negatively correlated with output and citation impact. DR also had a negative but weak correlation with the number of publications and 10% most frequently cited paper.

Beyond the inhibitory action against the gibberellin biosynthesis, some plant growth retardants (PGRs) can play an important role in regulating plant responses to abiotic stress through the induction of different tolerance mechanisms. The aim of the present study was the exploitation of the potential of PGRs in enhancing the resistance to drought stress in Stevia rebaudiana Bert. Therefore, the effects of three PGRs on stevia plants grown under drought stress condition were investigated. Stevia plants were first subjected to water stress and, second, treated with PGRs to detect PGRs effect on biometric, productive and phytochemical characteristics of drought stressed-plants. The control plants were uniformly irrigated at 3-day intervals, while water-stress conditions were imposed by watering the plants at 12-day intervals. Subsequently, the Chlorocholine chloride (CCC, as Copalyl diphosphate synthase inhibitor and Kaurene synthase inhibitor), Paclobutrazol (PBZ, as Kaurene oxidase inhibitor) and Daminozide (DAM, as anti-gibberellins) were applied in drought stressed-plants. The CCC and DAM were sprayed on stevia shoots, while PBZ was drenched. The obtained results showed that leaf dry weight of stevia plants was significantly reduced by drought stress, but this parameter increased as a consequence of CCC and PBZ treatments. Drought stress also caused a significant reduction in total steviol glycoside (SVglys) content. This reduction was more pronounced in drought stressed-plants treated with CCC, while PBZ was able to counteract the SVglys reduction, with SVgly content similar to that observed in the control. Similarly, PBZ was able to increase the soluble sugar production and total antioxidant capacity in the leaves of stressed-stevia plants. These findings suggested that CCC and, in particular, PBZ had a protective effect on stevia growth under drought stress by induction of antioxidant defenses and soluble sugar production. CCC seems to inhibit gibberellin biosynthesis, preventing the SVglys production, while DAM and PBZ, as gibberellin inhibitors, didn't have a negative effect on SVglys production in drought stressed-plants. This observation seems to emphasize their role in limiting the rate of target enzymes of CCC in SVglys biosynthetic pathway. Moreover, the induction of glucose production, as a substrate for SVglys biosynthesis, could be a convincing evidence for SVglys promotion in PBZ treated-plants.

A new composite nanofiber of polyacrylonitrile doped with copper benzene-1,3,5-tricarboxylate metal-organic framework was fabricated by electrospinning and used as a microsorbent in the solid-phase extraction of trace tetracycline. The chemical structure of the adsorbent was studied by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller surface area analysis, and Barrett-Joyner-Halenda pore size and volume analysis techniques. The significant parameters of the method including desorption solvent kind and volume, adsorbent mass, pH, and salt percentage were investigated. At the optimized conditions, the linear range was 8-1000 μg/L with a determination coefficient (R2 ) of 0.9954. The limits of detection and quantification were 2.40 and 8.00 μg/L, respectively. The inter- and intraday precisions were 4.7 and 3.4%, respectively. The developed extraction method was followed by high-performance liquid chromatography and applied for the determination of tetracycline in human blood plasma, and good relative recoveries (97.3-104.5%) were obtained.

Brass/molybdenum composites containing 30, 70 and 85 wt% Mo were synthesized by mechanical milling and densification of the brass/Mo powder mixtures. The milled powders were separately consolidated by spark plasma and pressureless sintering processes. The pressureless sintered samples were cold compacted under 300, 450 and 600 MPa before sintering. The results showed that by increasing the cold pressure up to 600 MPa, the relative density of the sintered samples with 70 and 85 wt% Mo were increased. However, the highest relative density of the brass-30 wt% Mo composites was achieved for the samples which were cold compacted under 450 MPa before sintering. The microstructural observations by scanning electron microscopy and energy dispersive spectroscopy analyses revealed that the distribution of Mo particles within the brass matrix of brass-30 wt% Mo composites was not as fine as the other samples. According to the results, the relative density and hardness of the spark plasma sintered samples was higher than that of the pressureless sintered ones. Moreover, increasing the volume percent of molybdenum has led to decreasing the relative density of the spark plasma sintered samples. The flexural strength of the spark plasma sintered composites with 30, 70 and 85 wt% Mo were 397, 376 and 114 MPa, respectively.