Potential Region Research Articles

Test-Retest performance of [18F]MK-6240 tau burden and relative delivery indices in cognitively normal older subjects using PET/MRI

Abstract Accurate interpretation of quantitative PET outcomes hinges on understanding the test-retest variability (T-RT). Previous studies of the tau-PET ligand [18F]MK-6240 reported adequate T-RT performance of tau burden estimates over a short-term 21-day and over a longer-term 6-month T-RT period, primarily involving Alzheimer’s disease (AD) and cognitively normal (CN) subjects, respectively. However, several T-RT characteristics have not yet been reported, particularly in older CN (oCN) subjects. Here, we investigate the short-term T-RT performance of dynamic [18F]MK-6240 outcomes in a group largely consisting of oCN. We report T-RT for uptake in potential reference regions, for extracerebral off-target signal, and for estimates of tau burden and relative delivery indices in tau-bearing target regions. Eight participants (7 oCN, 1 AD) underwent baseline dynamic [18F]MK-6240 PET/MRI (Biograph mMR) and a retest follow-up PET/MRI scan within approximately 3 weeks. T-RT was evaluated using absolute percentage differences and intraclass correlation coefficients (ICC) in three groups of regions: 1) potential reference regions using standardized-uptake-values 90-110 minutes post-injection (SUV90-110min); 2) target regions using SUV ratios (SUVR90-110min), distribution volume ratios (DVR), and relative delivery (R1); and 3) extracerebral region using SUVR90-110min. A voxel-based partial volume correction (PVC) was applied. T-RT was evaluated with and without PVC. In oCN subjects, the SUV90-110min T-RT in the evaluated reference regions ranged from 6-11% (ICC > 0.9); target region T-RT was similar for SUVR90-110min (4-9%, ICC: 0.62-0.97), DVR (3-10%, ICC: 0.66-0.92), and R1 (3-14%, ICC: 0.52-0.97). PVC had minimal impact on reference region SUV90-110min T-RT, but increased target region T-RT variability (SUVR90-110min: 10-26%; DVR: 6-22%; R1: 4-20%). Extracerebral SUVR90-110min exhibited higher T-RT variability (~12%, ICC: 0.85) than other target regions (average 6%) and increased to ~15% after PVC. Our findings are consistent with previous reports and provide further evidence of acceptable [18F]MK-6240 T-RT in low-signal oCN subjects. Our results suggest [18F]MK-6240 is suitable for detecting early tau deposition and longitudinal changes over time, and further support the viability of [18F]MK-6240 R1 to evaluate longitudinal changes in perfusion. PVC increased T-RT variability in tau burden and R1 outcomes. Notably, the extracerebral signal exhibited higher T-RT variability than other target and reference regions and may affect their signal.

Electronic interactions between SnO2 crystals and porous N-doped carbon nanoflowers accelerate electrochemical reduction of CO2 to formate

The electrochemical carbon dioxide reduction reaction (CO2RR) to formic acid or formate is a highly effective approach for achieving carbon neutrality. However, multiple proton-coupling-electronic processes and the instability of the catalysts caused by surface poisoning greatly limit the overall efficiency of CO2RR to formate. Here, a facile method was developed to anchor ∼2.60 nm SnO2 crystals onto porous N-doped carbon nanoflowers (SnO2@N-GPC) for high-efficiency formate production. The maximum Faraday efficiency (FE) of the SnO2@N-GPC reached 96.3 % at −1.2 V vs reversible hydrogen electrode (RHE) and was more than 80.0 % in the potential region from −1.0 to −1.5 V vs RHE with ten hours of operating stability. The experimental results and density functional theory (DFT) calculations demonstrated that the electronic interactions between SnO2 and N-GPC precipitated by electron transfer from SnO2 to N-GPC at the interface improved the phase stability of the SnO2@N-GPC, which improved its stability for the CO2RR. Furthermore, the electronic interactions enhanced the adsorption of CO2 on the catalyst, accelerating the rate of the formation of key intermediates, and reducing the energy barrier of the rate-limiting step for generating formate. This study provides an efficient strategy for developing highly active and stable non-precious metal catalysts for the conversion of CO2 to high-value chemicals.

Discovery and characterization of temperature adaptation modules by mining L-glutamate decarboxylase derived from psychrophilic microorganisms

Directed alterations of the enzyme's temperature adaptations, such as thermostability and optimal catalytic temperature (Topt), are usually the way to go in order to meet the applications, however they are limited by the understanding between protein structure and function. Glutamate decarboxylase (GADs) is a common enzyme in the food industry. In this study, we identified and characterized three novel L-glutamate decarboxylases from psychrophilic microorganisms. Interestingly, the two enzymes (Gad Psy.Y/Gad Psy.F) showed significant differences in temperature adaptation. Through multiple sequence alignment and structural analysis, two potential regions that may affect the Topt and thermostability of the GAD, termed temperature adaptation modules (TAMs), were targeted. To validate the role of TAMs, we constructed mutants with bi-directional transplants of TAMs, which ultimately significantly altered the temperature adaptation of Gad Psy.Y and Gad Psy.F. Molecular dynamics simulations analysis demonstrated that the introduction and disruption of salt bridges in the mutant TAMs are crucial for this alteration. These findings deepen the understanding of the mechanisms of protein temperature adaptation and provide implications for protein engineering, while also offering advantageous enzymes to support the biosynthesis of GABA.

Ice nucleating ability of mineral particles from subtropical South American deserts

Mineral aerosols are one of the most important ice nucleating particles (INPs) because their efficiency in nucleating ice, wide transport and largest mass contribution to particulate matter in the atmosphere. They are sourced from the arid regions of the world. In this context, this work evaluates the INP potential of fourteen topsoil samples collected from subtropical South American deserts, the major source of mineral aerosols in South America, in the immersion freezing mode. Samples were obtained from three distinct regions located in the South American Arid Diagonal and recognized as potential dust source areas: the Puna-Altiplano Plateau in the north, the central-west of Argentina, and Patagonia in the south. In general, results reveal that samples from the Puna-Altiplano and Patagonia regions, and the central-west of Argentina region exhibit the highest and lowest INP abilities, respectively. The active sites per unit surface area for a given temperature were calculated and compared with previously reported values. The results demonstrate that soil mineral particles from the region of study exhibit ice nucleating abilities comparable to the inorganic fraction of agricultural soils of central Argentina. No direct relationship was identified between INP ability and the major minerals observed in the samples. This study is the first to analyze the ice nucleation properties of soil samples collected along the South American Arid Diagonal and one of the few in South America. Since the analyzed topsoil particles were collected from potential dust source regions, this work contributes to understanding the role of aerosols in initiating atmospheric ice formation, providing valuable data for empirical parameterizations. This could contribute to the improvement in the performance of climate models, as the obtained results suggest that the underestimation of coarse and super-coarse aerosols at altitudes relevant for cloud formation may lead to underestimations in INP concentrations, particularly in regions near to the emission sources.

Comprehensive characterization and phylogenetic analysis of the complete plastomes of two ant–orchids, Caularthron bicornutum and Myrmecophila thomsoniana

BackgroundMyrmecophytes, characterized by specialized structures like hollow stems that facilitate mutualistic relationships with ants, serve as an important system for studying ant-plant interactions and the adaptation mechanisms. Caularthron and Myrmecophila are exemplary myrmecophytes within Orchidaceae. Previous studies suggested a genetic relationship between these two genera, placing them within Laeliinae (Epidendreae), yet the precise phylogenetic positioning remained uncertain. The absence of available plastome resources has hindered investigations into plastome evolution and phylogeny.ResultsIn this study, we sequenced and assembled the complete plastomes of Caularthron bicornutum and Myrmecophila thomsoniana to elucidate their plastome characteristics and phylogenetic relationships. The determined plastome sizes were 150,557 bp for C. bicornutum and 156,905 bp for M. thomsoniana, with GC contents of 37.3% and 37.1%, respectively. Notably, M. thomsoniana exhibited a distinctive IR expansion and SSC contraction, with the SSC region measuring only 4532 bp and containing five genes (ccsA, ndhD, rpl32, psaC, and trnL-UAG), a unique feature observed for the first time in Epidendreae. Comparative analyses with species from the related genus Epidendrum revealed that C. bicornutum plastome exhibited conserved genome size, GC content, gene content, and gene order. A total of 32 and 33 long sequence repeats, 50 and 40 tandem repeats, and 99 and 109 SSRs were identified in the plastomes of C. bicornutum and M. thomsoniana, respectively. The RSCU analysis demonstrated a consistent pattern in both plastomes, with 29 out of 30 codons with RSCU values greater than 1 featuring A/U at the third codon position. Leucine was the most prevalent amino acid, while Cysteine was the least common. Four potential DNA barcoding regions with Pi values exceeding 0.07, namely ycf1, ccsA–psaC, petN–psbM, and accD–psaI, were identified for subsequent phylogenetic reconstructions within Laeliinae. Phylogenetic analysis underscored the close relationships among Caularthron, Epidendrum, and Myrmecophila.ConclusionsThis study represents the first comprehensive analysis of the plastome characteristics of Caularthron bicornutum and Myrmecophila thomsoniana. Through our characterization and phylogenetic analyses, we unveiled the unique IR expansion/SSC contraction and further elucidated their phylogenetic positions. Our research contributes significant data and insights into the dynamic evolution of ant–orchid plastomes and the phylogeny of the Laeliinae.

Potentiostatic electrolysis of fluoride melts with zirconium oxide additives

Currently, the demand for zirconium-based alloys and materials is growing significantly due to their high thermal and corrosion resistance combined with mechanical strength. Existing technologies for producing zirconium and its alloys are complicated by the high temperature of the process, or labor intensity and multi-stage nature, which significantly increases the cost of the target material up to the loss of profitability of the process. Electrochemical synthesis of zirconium and its alloys in fluoride-based melts, using zirconium oxides as the main metal-containing consumable component, seems more profitable. In this work, a series of electrolysis tests were carried out to deposit Al-Zr alloy at a potential of 1.6 V on graphite and molybdenum cathodes. According to the previously obtained results, in the presence of ZrO2 in the KF-AlF3-Al2O3 melt, a plateau and a discharge peak of electroactive ions appear on the cathode branch of the voltammograms at potentials of -1.4 and -1.7 V, ZrI and ZrII, respectively. Similar responses appear on tungsten at potentials of -1.3 and -1.6 V, respectively, and in the potential region of -1.9 V there is a clear peak (Al) of electroreduction of aluminum ions. As a result of electrolysis, it was found that the graphite anode was consumed, and a fairly well-bonded deposit was formed on the cathode. Part of the cathode deposit was mechanically separated from the cathode for analysis of its chemical and phase composition. Based on the results of X-ray phase analysis, it was found that the cathode deposit mainly consists of Al3Zr and aluminum compounds with molybdenum impurities, with the composition Al12Mo, which is consistent with known ideas about the formation of intermetallic compounds during the interaction of aluminum with other metals. Electrolysis of the melt on the graphite cathode was carried out under similar conditions. Based on a microphotograph of the cathode cross section, it was found that during electrolysis, a layer of deposit containing both zirconium and aluminum was formed at the electrode-electrolyte phase boundary.

Inter-farm wake effect on layout optimization: Case study of standardized two-phase wind farms

Due to the limited availability of suitable sites, wind farms are now being constructed closer to each other or in phases, highlighting the importance of understanding the wake effects between adjacent farms. To address this, a study case is standardized from two adjacent wind farms, Rønland I and II. The standardized case incorporates variations in spatial and scale factors of wind farms. To investigate the wake effects between wind farms, this study is conducted under the inflow of a single directional sector of 30 degrees. When inter-farm spacing increases, the distribution of potential power undergoes a transition from a non-uniform stripe pattern to a gradient pattern, ultimately approaching a uniform pattern. The pattern of power potential appropriately explains the different trends of optimized layouts. Moreover, a 95 % unwaked potential power region (UPPR) is defined and enclosed by the contour line of 95 % of power potential without wake effects. The optimized layouts demonstrate different patterns depending on the proportion of downstream wind farms shaded by 95 % UPPR. When the 95 % UPPR predominantly covers the design region, wind turbines tend to concentrate near the downwind edge. As the region moves further away, the layout transitions to a double-column staggered distribution.

Hemodynamic evaluation of endovascular techniques of stenting and coiling for the treatment of internal carotid artery aneurysm: a computational study

The selection optimum endovascular method for the treatment of different cerebral aneurysms has been the main challenge for surgeons. In the present article, the computational technique is used for the hemodynamic evaluation of two main endovascular techniques of stent and coiling for the reduction of the hemorrhage risk of ICA aneurysms. Comprehensive analyses of the blood flow are performed to detect potential regions with high risk at critical stages of the cardiac cycle. Two coiling porosity conditions and stent deformation have been investigated via computational study to reveal the main change related to hemodynamics when these techniques are implemented. The hemodynamic results of this study show that the endovascular technique is more efficient in small aneurysms rather than giant ones. Meanwhile, the stent treatment of the giant saccular aneurysm is effective when the parent vessel of this type of aneurysm is fully aligned and limited blood flow enters the sac area.

Ixochymostatin, a trypsin inhibitor-like (TIL) protein from Ixodes scapularis, inhibits chymase and impairs vascular permeability

Ticks obtain a blood meal by lacerating small blood vessels and ingesting the blood that flows to the feeding site, which triggers various host responses. However, ticks face the challenge of wound healing, a process involving hemostasis, inflammation, cell proliferation and migration, and remodeling, hindering blood acquisition. To overcome these obstacles, tick salivary glands produce an array of bioactive molecules. Here, we characterize ixochymostatin, an Ixodes scapularis protein belonging to the trypsin inhibitor-like (TIL) family. It is expressed in multiple developmental stages and in tick salivary glands and acts as a slow and tight-binding inhibitor of chymase, cathepsin G, and chymotrypsin. Predictions for the tertiary structure complex between ixochymostatin and chymase suggest a direct interaction between the inhibitor reactive site loop and protease active sites. In vitro, ixochymostatin protects the endothelial cell barrier against chymase degrading action, decreasing cell permeability. In vivo, it reduces vascular permeability induced by chymase and compound 48/80, a mast cell degranulator agonist, in a mouse model. Additionally, ixochymostatin inhibits the chymase-dependent generation of vasoconstrictor peptides. Antibodies against ixochymostatin neutralize its inhibitory properties, with epitope mapping identifying potential neutralization regions. Ixochymostatin emerges as a novel tick protein modulating host responses against tick feeding, facilitating blood acquisition.

Identification of Salient Brain Regions for Anxiety Disorders Using Nonlinear EEG Feature Analysis.

In this paper, we present a novel approach for identifying salient brain regions and interpreting the ability of nonlinear EEG features to discriminate between anxiety disorders and healthy controls. The proposed method involves the integration of advanced EEG preprocessing and artefact correction, nonlinear feature extraction using conditional permutation entropy, and interpretable machine learning to identify relevant electrodes. The extracted nonlinear features show statistically significant differences between classes, demonstrating high discriminative ability. The discriminative ability was confirmed with T-tests (p = 1.05e-10) and Mann-Whitney U tests (p = 2.65e-11), demonstrating robust statistical significance. Classification results support these findings and guide the identification of relevant electrodes, enhancing the interpretability of the discriminative features. This approach highlights potential brain regions critical for anxiety disorder diagnosis, paving the way for more targeted interventions and improved clinical outcomes.

Combustion-driven inorganic nitrogen in PM2.5 from a city in central China has the potential to enhance the nitrogen load of North China

Inorganic nitrogen (NH4+ and NO3−) is a significant component of PM2.5, influencing not only regional ecological systems but also on other regions through the migration of air masses. However, few studies have simultaneously investigated the sources of NH4+ and NO3−, and their potential transport pathways remain poorly understood. Here, daily PM2.5 samples were collected in Jiaozuo, a key city in the air pollution transmission channel to the north China, from 1 September to 5 December, 2017. Major water-soluble inorganic ions and the isotope compositions of NH4+ and NO3− in PM2.5 were analyzed. The results indicated substantial amounts of inorganic nitrogen in PM2.5, particularly at high PM2.5 concentrations. The Bayesian isotope mixing model (MixSIAR) results revealed that combustion sources contributed 79.5 % to NO3− and 51.6 % to NH4+. Moreover, the medium to high potential source regions for combustion-related NH3 is basically consistent with combustion-related NOx. Therefore, stringent regulation of combustion emissions has the potential to mitigate inorganic nitrogen pollution in PM2.5 in Jiaozuo. The results of the forward trajectory cluster and PSCF (potential source contribution function) analysis revealed that a significant amount of combustion-driven inorganic nitrogen in PM2.5 from Jiaozuo will transport to downwind area, particularly north China. Combustion-driven inorganic nitrogen levels carried by these air masses exceeded half the average value for cities in North China during the same period. Our study highlights that combustion emissions dominate the inorganic nitrogen sources in PM2.5 and that substantial amounts of combustion-driven inorganic nitrogen can be transported from Jiaozuo to North China, potentially enhancing the nitrogen load in those areas.

Vertical Distribution, Diurnal Evolution, and Source Region of Formaldehyde During the Warm Season Under Ozone-Polluted and Non-Polluted Conditions in Nanjing, China

Formaldehyde (HCHO), a key volatile organic compound (VOC) in the atmosphere, plays a crucial role in driving photochemical processes. Satellite-based observations of column concentrations of HCHO and other gaseous pollutants (e.g., NO2) have generally been used in previous studies to elucidate the mechanisms behind secondary organic aerosol (SOA) and ozone (O3) formation. This study aimed to investigate the characteristics of HCHO by retrieving its vertical profile over Nanjing during the warm season (May–June 2022) and analyzing the diurnal variation in vertical distribution and potential source regions on non-polluted (MDA8 O3 < 160 μg m−3, NO3P) and O3-polluted (MDA8 O3 ≥ 160 μg m−3, O3P) days. Under both conditions, HCHO was primarily concentrated below 1.5 km altitude, with average vertical profiles displaying similar Boltzmann-like distributions. However, HCHO concentrations on O3P days were 1.2–1.6 times higher than those on non-polluted days at the same altitude below 1.5 km. Maximum HCHO concentrations occurred in the afternoon, while the peak value in the 0.1–0.4 km layers was reached around noon (~11:00 a.m.). The variation rates (VR) of HCHO in the 0.3–1.2 km altitudes had a maximum on O3P days (approximately 0.33 ppbv h−1), and were significantly higher (p < 0.01) than the VR observed on NO3P days (0.14–0.20 ppbv h−1). The analysis of footprints showed that HCHO concentrations were jointly influenced by the upstream region and the surroundings of the study site. The study results improve the understanding of the vertical distribution and potential source regions of HCHO.

Two-stage ship detection at long distances based on deep learning and slicing technique.

Ship detection over long distances is crucial for the visual perception of intelligent ships. Since traditional image processing-based methods are not robust, deep learning-based image recognition methods can automatically obtain the features of small ships. However, due to the limited pixels of ships over long distances, accurate features of such ships are difficult to obtain. To address this, a two-stage object detection method that combines the advantages of traditional and deep-learning methods is proposed. In the first stage, an object detection model for the sea-sky line (SSL) region is trained to select a potential region of ships. In the second stage, another object detection model for ships is trained using sliced patches containing ships. When testing, the SSL region is first detected using the trained 8th version of You Only Look Once (YOLOv8). Then, the SSL region detected is divided into several overlapping patches using the slicing technique, and another trained YOLOv8 is applied to detect ships. The experimental results showed that our method achieved 85% average precision when the intersection over union is 0.5 (AP50), and a detection speed of 75 ms per image with a pixel size of 1080×640. The code is available at https://github.com/gongyanfeng/PaperCode.

High-throughput root phenotyping and association analysis identified potential genomic regions for phosphorus use efficiency in wheat (Triticum aestivum L.).

Association analysis identified 77 marker-trait associations (MTAs) for PUE traits, of which 10 were high-confidence MTAs. Candidate-gene mining and in-silico expression analysis identified 13 putative candidate genes for PUE traits. Bread wheat (Triticum aestivum L.) is a major cereal crop affected by phosphorus (P) deficiency, which affects root characteristics, plant biomass, and other attributes related to P-use efficiency (PUE). Understanding the genetic mechanisms of PUE traits helps in developing bread wheat cultivars that perform well in low-P environments. With this objective, we evaluated a bread wheat panel comprising 304 accessions for 14 PUE traits with high-throughput phenotyping under low-P and optimum-P treatments and observed a significant genetic variation among germplasm lines for studied traits. Genome-wide association study (GWAS) using 14,025 high-quality single-nucleotide polymorphisms identified 77 marker-trait associations (MTAs), of which 10 were chosen as high-confidence MTAs as they had > 10% phenotypic variation with logarithm of odds (LOD) scores of more than five. Candidate-gene (CG) mining from high-confidence MTAs identified 180 unique gene models, of which 78 were differentially expressed (DEGs) with at least twofold change in expression under low-P over optimum-P. Of the 78-DEGs, 13 were thought to be putative CGs as they exhibited functional relevance to PUE traits. These CGs mainly encode for important proteins and their products involved in regulating root system architecture, P uptake, transport, and utilization. Promoter analysis from 1500bp upstream of gene start site for 13 putative CGs revealed the presence of light responsive, salicylic-acid responsive, gibberellic-acid (GA)-responsive, auxin-responsive, and cold responsive cis-regulatory elements. High-confidence MTAs and putative CGs identified in this study can be employed in breeding programs to improve PUE traits in bread wheat.

Cadmium (Cd) Tolerance and Phytoremediation Potential in Fiber Crops: Research Updates and Future Breeding Efforts

Heavy metal pollution is one of the most devastating abiotic factors, significantly damaging crops and human health. One of the serious problems it causes is a rise in cadmium (Cd) toxicity. Cd is a highly toxic metal with a negative biological role, and it enters plants via the soil–plant system. Cd stress induces a series of disorders in plants’ morphological, physiological, and biochemical processes and initiates the inhibition of seed germination, ultimately resulting in reduced growth. Fiber crops such as kenaf, jute, hemp, cotton, and flax have high industrial importance and often face the issue of Cd toxicity. Various techniques have been introduced to counter the rising threats of Cd toxicity, including reducing Cd content in the soil, mitigating the effects of Cd stress, and genetic improvements in plant tolerance against this stress. For decades, plant breeders have been trying to develop Cd-tolerant fiber crops through the identification and transformation of novel genes. Still, the complex mechanism of Cd tolerance has hindered the progress of genetic breeding. These crops are ideal candidates for the phytoremediation of heavy metals in contaminated soils. Hence, increased Cd uptake, accumulation, and translocation in below-ground parts (roots) and above-ground parts (shoots, leaves, and stems) can help clean agricultural lands for safe use for food crops. Earlier studies indicated that reducing Cd uptake, detoxification, reducing the effects of Cd stress, and developing plant tolerance to these stresses through the identification of novel genes are fruitful approaches. This review aims to highlight the role of some conventional and molecular techniques in reducing the threats of Cd stress in some key fiber crops. Molecular techniques mainly involve QTL mapping and GWAS. However, more focus has been given to the use of transcriptome and TFs analysis to explore the potential genomic regions involved in Cd tolerance in these crops. This review will serve as a source of valuable genetic information on key fiber crops, allowing for further in-depth analyses of Cd tolerance to identify the critical genes for molecular breeding, like genetic engineering and CRISPR/Cas9.

Fundamentals and Implication of Point of Zero Charge (PZC) Determination for Activated Carbons in Aqueous Electrolytes.

The point of zero charge (PZC) is a crucial parameter for investigating the charge storage mechanisms in energy storage systems at the molecular level. This paper presents findings from three different electrochemical techniques, compared for the first time: cyclic voltammetry (CV), staircase potentio electrochemical impedance spectroscopy (SPEIS), and step potential electrochemical spectroscopy (SPECS), for two activated carbons (ACs) with 0.1molL-1 aqueous solution of LiNO3, Li2SO4, and KI. The charging process of AC operating in aqueous electrolytes appears as a complex phenomenon - all ionic species take an active part in electric double-layer formation and the ion-mixing zone covers a wide potential region. Therefore, the so-called PZC should not be considered as an absolute one-point potential value, but rather as a range of zero charge (RZC). SPECS technique is found to be a universal and fast method for determining RZC, as applied here together with the EQCM. In most cases, the RZC covers a potential range from ≈100 to ≈200mV and the correlation of the range with the carbon microtexture is clear, highlighting the role of the ion-sieving effect. It is postulated that PZC for porous materials in aqueous electrolytic solutions should be considered instead as RZC.

A nonrevisiting genetic algorithm based on multi-region guided search strategy

Recently, nonrevisiting genetic algorithms have demonstrated superior capabilities compared with classic genetic algorithms and other single-objective evolutionary algorithms. However, the search efficiency of nonrevisiting genetic algorithms is currently low for some complex optimisation problems. This study proposes a nonrevisiting genetic algorithm with a multi-region guided search to improve the search efficiency. The search history is stored in a binary space partition (BSP) tree, where each searched solution is assigned to a leaf node and corresponds to a search region in the search space. To fully exploit the search history, several optimal solutions in the BSP tree are archived to represent the most potential search regions and estimate the fitness landscape in the search space. Except for the conventional genetic operations, the offspring can also be generated through multi-region guided search strategy, where the current solution is first navigated to one of the candidate search regions and is further updated towards the direction of the optimal solution in the search history to speedup convergence. Thus, multi-region guided search can reduce the possibility of getting trapped in local optima when solving problems with complex landscapes. The experimental results on different types of test suites reveal the competitiveness of the proposed algorithm in comparison with several state-of-the-art methods.

Interdisciplinary insights into the cultural and chronological context of chili pepper (Capsicum annuum var. annuum L.) domestication in Mexico

This study investigates the temporal and spatial factors driving the domestication of Capsicum annuum var. annuum L. in Mexico. This species exhibits the greatest morphological diversity in fruit among Capsicum species-a characteristic that is even more pronounced in contemporary landraces cultivated by indigenous communities. Despite the chili pepper's integral role in regional culinary traditions, its domestication history in this region remains poorly understood, often subject to scholarly interpretations that marginalize or oversimplify archaeological evidence. To address this gap, our interdisciplinary team of archaeologists, botanists, and ecologists combine modern and archaeological Capsicum seed data, diachronic archaeological site locations, and ecological niche modeling to identify potential regions where early human populations and the closest wild ancestors may have coexisted. Our results show spatial correlations between early Capsicum distribution and archaeological site prevalence, suggesting that the beginning of the domestication process occurred in ecologically suitable areas for both wild Capsicum and human settlement. These findings challenge previous hypotheses regarding highland/dry cave domestication regions, as our data indicate that lowland regions-specifically the Yucatán Peninsula and southern coastal Guerrero-were more conducive to early encounters between wild Capsicum and humans. We propose a geographically diffuse and protracted model of chili pepper domestication-driven by a ruderal pathway-which involved at least two asynchronous events across Mexico.

"Transcriptional Regulation of human NMNAT2: Insights from 3D Genome Sequencing and Bioinformatics".

Nicotinamide mononucleotide adenylyl transferases 2 (NMNAT2) is a crucial nicotinamide adenine dinucleotide (NAD)-synthesizing enzyme essential for neuronal health. In the Religious Orders Study/Memory and Aging Project (ROSMAP), human brain levels of NMNAT2 mRNA positively correlated with cognitive capabilities in older adults. NMNAT2 mRNA abundance is significantly reduced following various insults or proteinopathies. To elucidate the transcriptional regulation of NMNAT2, we employed circular chromosome conformation capture followed by high-throughput sequencing (4C-seq) to identify potential NMNAT2 enhancer and silencer regions by determining genomic regions interacting with the NMNAT2 promoter in human SH-SY5Y cells. We discovered distinct NMNAT2 promoter interactomes in undifferentiated versus neuron-like SH-SY5Y cells. Utilizing bioinformatics analyses, we identified putative transcriptional factors and NMNAT2-associated genes. Notably, the mRNA levels of many of these genes showed a significant correlation with NMNAT2 mRNA levels in ∼400 single-nuclei RNA-seq datasets from ROSMAP. Additionally, using CRISPR-Cas9 strategies, we confirmed the requirement of two specific genomic regions within the interactomes and four transcription factors in regulating NMNAT2 transcription. In summary, our study identifies genomic loci containing NMNAT2 regulatory elements and predicts associated genes and transcription factors through computational analyses.

Significant shift of footprint patterns and pollutant source contributions: insights from observations at Shanghuang observatory, East China

Abstract As two of the most important products of the combustion process, carbon dioxide (CO2) and carbon monoxide (CO) are commonly used as tracers for combustion source assignment. Their relationship will help to better understand the regional carbon cycle and assess climate forcing effects. In this study, mixing ratios of CO2 and CO were continuously measured using a Picarro gas concentration analyzer at the Atmospheric Boundary Layer Eco-Environmental Shanghuang Observatory, Chinese Academy of Sciences (ABLECAS) throughout 2022–2023. The variability of the mixing ratio of CO to CO2 (ΔCO/ΔCO2) in a 1 h time interval was calculated based on linear slope analysis after background values were determined and subtracted. The results showed that the mixing ratio of CO had a clear seasonal variability with a moderate increase in the spring (249.1 ± 59.6 part per billion (ppb)) and winter (257.8 ± 90.3 ppb), mostly due to more frequent transport from north of the Yangtze River. ΔCO/ΔCO2 at the ABLECAS varied with air mass origin, with a linear slope 0%–1% on a 1 h basis. Relatively high ΔCO/ΔCO2 values for an air mass from the north in the winter indicate that the emission sources had lower combustion efficiency. In summer, the ΔCO/ΔCO2 ratio mostly reflected the background conditions for air masses from marine areas. The potential source regions and contribution assignments were evaluatedat the ABLECAS according to source–receptor relationship analysis using the FLEXPART model with CO as a pollutant tracer from 2015 to 2023. We found that the footprint of an air mass had a clear transition period between 2018 and 2019, and a synoptic anomaly, related to Arctic Oscillation strength and west Pacific subtropical high position, plays a key role in influencing the pollutant transport patterns. This study provides a scientific basis for the formulation of air quality regulation policy, and helps to implement the national carbon neutralization strategy.