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In this article, we study the multidimensional second-order processes with time-dependent spectra. This is indeed a large class of second-order processes that includes periodically correlated processes and evolutionary processes. We provide new characterization to read an evolutionary process as the Fourier transform of a stationary kernel. We present the corresponding spectral characterization and the moving average representation for doing prediction. The multivariate evolutionary ARMA processes are introduced as well. Insights to the multivariate evolutionary AR(1) processes are provided.

Intensive agriculture development and achievement to higher profitability has inflicted permanent damage on agroecosystems. Rapid deterioration of structure and functional properties in agroecosystems has intensified the need for research on agroecosystem health and management. To assess the health status of wheat agroecosystems in the agricultural lands of Bandar-e-Turkmen county (Golestan province, Iran), we were used the variables of weed and natural enemies biodiversity, soil health (carbon and organic matter, microbial respiration, earthworm, soil salinity, and acidity), environmental indexes (environmental effects of pesticides (EIQ) and nitrate leaching) and vegetation indexes (RVI, cultivar type, and grain yield). In this study, thematic layers were prepared in ArcGIS and overlayed according to three scenarios. Then final layer was classified into three classes of health. Based on the results, only 8.47% (5 fields) were located in the first health class. These fields were characterized by high grain yield, low weed biodiversity, minimal pesticides use, optimal soil conditions, high RVI, and the presence of earthworms and natural enemies. Also, we found that 42 fields (71.19%) were placed in the second health class. Increase of biodiversity and population of weeds, lower grain yield, and reducing the quantity and quality of soil variables were important factors that reduced the health degree of these fields. Based on the results, 20.34% of the area (12 fields) in the central and western parts of the county was placed in the unhealthy class. It seems that increasing the environmental restrictions, including salinity higher than 6 ds/m, high weed diversity, increasing the consumption of harmful and dangerous pesticides with high environmental impact, and less grain yield than the potential of cultivars, were the main reasons for placing these fields in the unhealthy class. Also, the most important factors of decreasing the health degree of fields, frequency of weeds, increasing consumption of chemical pesticides, low soil organic matter, absence of earthworms, and decreasing grain yield were identified. Generally, management of weeds, implementation of crop rotation, preservation of plant residues on the soil surface, and development of conservation agriculture can help to improve the health indicators of wheat agroecosystems.

The subjective sense of certainty, or confidence, in ambiguous sensory cues can alter the interpretation of reward feedback and facilitate learning. We trained rats to report the orientation of ambiguous visual stimuli according to a spatial stimulus-response rule that must be learned. Following choice, rats could wait a self-timed delay for reward or initiate a new trial. Waiting times increase with discrimination accuracy, demonstrating that this measure can be used as a proxy for confidence. Chemogenetic silencing of BLA shortens waiting times overall whereas ACC inhibition renders waiting times insensitive to confidence-modulating attributes of visual stimuli, suggesting contribution of ACC but not BLA to confidence computations. Subsequent reversal learning is enhanced by confidence. Both ACC and BLA inhibition block this enhancement but via differential adjustments in learning strategies and consistent use of learned rules. Altogether, we demonstrate dissociable roles for ACC and BLA in transmitting confidence and learning under uncertainty. The degree of subjective confidence in deciding based on ambiguous sensory cues facilitates learning. Here, the authors report distinct functions of the basolateral amygdala and anterior cingulate cortex on implicit confidence judgements as well as flexible learning under uncertain conditions in rats.

Morphological characterization of the lumbar spinal cord regeneration process was investigated in killifish A. hormuzensis , by using hematoxylin-eosin staining after spinal cord injury. An spinal cord injury was settled, and the injured tissue was sampled. Immediately after the spinal cord injury, the blood clot formation was detected at the injury epicenter and the ependymal layer, and at six hours post-injury (6 hpi), the inflammation and cavity formation occurred. The neural cell accumulation and beginning signs of the spinal cord regeneration were detected one-day post-injury (1 dpi) close to the ependymal layer and subependymal layer. In two 2 dpi, the tissue repair and regeneration progress were detected. The reformation of the ependymal canal happened at 3 dpi, followed by the completion of spinal cord regeneration at 5 dpi. The spinal cord regeneration potency in A. hormuzensis is relatively higher than in other traditional fish models. Studies on the regeneration of this interesting fish are new, therefore, further investigations are needed to explore additional information about various aspects of tissue regeneration. This study is important because killifishes have a short life span, show high environmental variation tolerance, and are easy to maintain and breed in laboratory conditions.

Wheat kernel shape and size has been under selection since early domestication. Kernel morphology is a major consideration in wheat breeding, as it impacts grain yield and quality. A population of 160 recombinant inbred lines (RIL), developed using an elite (ND 705) and a nonadapted genotype (PI 414566), was extensively phenotyped in replicated field trials and genotyped using Infinium iSelect 90K assay to gain insight into the genetic architecture of kernel shape and size. A high density genetic map consisting of 10,172 single nucleotide polymorphism (SNP) markers, with an average marker density of 0.39 cM/marker, identified a total of 29 genomic regions associated with six grain shape and size traits; ∼80% of these regions were associated with multiple traits. The analyses showed that kernel length (KL) and width (KW) are genetically independent, while a large number (∼59%) of the quantitative trait loci (QTL) for kernel shape traits were in common with genomic regions associated with kernel size traits. The most significant QTL was identified on chromosome 4B, and could be an ortholog of major rice grain size and shape gene GS3 or qGL3. Major and stable loci also were identified on the homeologous regions of Group 5 chromosomes, and in the regions of TaGW2 (6A) and TaGASR7 (7A) genes. Both parental genotypes contributed equivalent positive QTL alleles, suggesting that the nonadapted germplasm has a great potential for enhancing the gene pool for grain shape and size. This study provides new knowledge on the genetic dissection of kernel morphology, with a much higher resolution, which may aid further improvement in wheat yield and quality using genomic tools.

In this research, in order to increase the oxidation resistance of graphite, kaolin and alumina powder with different ratios (26A-74S, 49A-51S, 72A-28S) and slurry method were used to create an aluminosilicate coating on the graphite substrate. In order to reduce the difference in the coefficients of thermal expansion of graphite with aluminosilicate coating, aluminum metaphosphate coating as an interlayer was prepared on the surface of graphite by cathodic electrochemical treatment. The isothermal oxidation test of the samples was carried out in air at a temperature of 1250 °C for 1, 3 and 5 h. The microstructure, chemical composition, and phase components of the coating were, respectively, analyzed by scanning electron microscope equipped with an energy-dispersive spectrometer and X-ray diffraction. The results indicated that, by increasing the withdrawal speed of the samples in slurry method, the amount of changes in the weight of the samples has increased and therefore had a direct effect on oxidation. In addition, it was approved that, at high-temperature oxidation, AlPO 4 glass phase forms on aluminum metaphosphate interlayer which retards graphite oxidation. Along with aluminum metaphosphate, aluminosilicate coating also produces a glass phase which fills and seals the voids on the surface which prevents the oxygen to reach the surface of graphite. The created double-layer coating including an interlayer of aluminum metaphosphate + slurry coating prepared with the ratio of 26A-74S as the optimal coating in this research was able to increase the oxidation resistance of graphite by 73% at a temperature of 1250 °C.

During the last few decades, open pit mines have been deepened to the remote depths of the ground such that removing great volumes of waste rocks may jeopardize their profitability. In such circumstances, an early transition from open pit to underground mining may prove more profitable. This is the case in many large-scale open pit mines, where considerable amount of mineral reserve remains beneath the pit bottom. This paper develops a set of classified integer programming models for determining an optimum transition depth (OTD) between open pit and various underground mining methods. The models lie within the scope of long-term production scheduling because the OTD is revealed through scheduling of all mineral reserve. To provide a quantitative analysis, two optimization models with distinct solution strategies are executed on a three-dimensional sector of a real orebody. The results indicate that the integrated models increase the total NPV of the mining operations by up to 8.62%. However, the scenario-based models enhance the primitive solution (the base scenario) by up to 3.42%. It is also shown that the integrated models present solutions that are practically more realistic.

In this paper, we consider fractional differential equations with the new fractional derivative involving a nonsingular kernel, namely, the Caputo-Fabrizio fractional derivative. Using a successive approximation method, we prove an extension of the Picard-Lindelöf existence and uniqueness theorem for fractional differential equations with this derivative, which gives a set of conditions, under which a fractional initial value problem has a unique solution.

The intraoperative in-vivo mechanical function of the left ventricle has been studied thoroughly using echocardiography in the past. However, due to technical and anatomical issues, the ultrasound technology cannot easily be focused on the right side of the heart during open-heart surgery, and the function of the right ventricle during the intervention remains largely unexplored. We used optical imaging and digital image correlation for the characterization of the right ventricle motion and deformation during open-heart surgery. This work is a pilot study focusing on one patient only with the aim of establishing the framework for long term research. These experiments show that optical imaging and the analysis of the images can be used to obtain similar parameters, and partly at higher accuracy, for describing the mechanical functioning of the heart as the ultrasound technology. This work describes the optical imaging based method to characterize the mechanical response of the heart in-vivo , and offers new insight into the mechanical function of the right ventricle.

Due to the metabolic nature of osteoporosis, this study was conducted to identify metabolomic studies investigating the metabolic profile of low bone mineral density (BMD) and osteoporosis. A comprehensive systematic literature search was conducted through PubMed, Web of Science, Scopus, and Embase databases up to April 08, 2020, to identify observational studies with cross-sectional or case-control designs investigating the metabolic profile of low BMD in adults using biofluid specimen via metabolomic platform. The quality assessment panel specified for the “omics”-based diagnostic research (QUADOMICS) tool was used to estimate the methodologic quality of the included studies. Ten untargeted and one targeted approach metabolomic studies investigating biomarkers in different biofluids through mass spectrometry or nuclear magnetic resonance platforms were included in the systematic review. Some metabolite panels, rather than individual metabolites, showed promising results in differentiating low BMD from normal. Candidate metabolites were of different categories including amino acids, followed by lipids and carbohydrates. Besides, certain pathways were suggested by some of the studies to be involved. This systematic review suggested that metabolic profiling could improve the diagnosis of low BMD. Despite valuable findings attained from each of these studies, there was great heterogeneity regarding the ethnicity and age of participants, samples, and the metabolomic platform. Further longitudinal studies are needed to validate the results and confirm the predictive role of metabolic profile on low BMD and fracture. It is also mandatory to address and minimize the heterogeneity in future studies by using reliable quantitative methods. Summary: Due to the metabolic nature of osteoporosis, researchers have considered metabolomic studies recently. This systematic review showed that metabolic profiling including different categories of metabolites could improve the diagnosis of low BMD. However, great heterogeneity was observed and it is mandatory to address and minimize the heterogeneity in future studies.