bluuebunny/crossref_metadata_2025 huggingface dataset:
An Improved Microseismic Signal Denoising Method of Rock Failure for Deeply Buried Energy Exploration
Authors: Tang Shibin , Ding Shun , Li Jiaming , Zhu Chun , Cao Leyu
Published: February 2023

Microseismic monitoring has become a well-known technique for predicting the mechanisms of rock failure in deeply buried energy exploration, in which noise has a great influence on microseismic monitoring results. We proposed an improved microseismic denoising method based on different wavelet coefficients of useful signal and noise components. First, according to the selection of an appropriate wavelet threshold and threshold function, the useful signal part of original microseismic signal was decomposed many times and reconstructed to achieve denoising. Subsequently, synthetic signals of different types (microseismic noise, microseismic current, microseismic noise current) and with various signal-to-noise ratios (SNRs, −10~10) were used as test data. Evaluation indicators (mean absolute error μ and standard deviation error σ) were established to compare the denoising effect of different denoising methods and verify that the improved method is more effective than the traditional denoising methods (wavelet global threshold, empirical mode decomposition and wavelet transform–empirical mode decomposition). Finally, the proposed method was applied to actual field microseismic data. The results showed that the microseismic signal (with different types of noise) could be fully denoised (car honk, knock, current and construction noise, etc.) without losing useful signals (pure microseismic), suggesting that the proposed approach provides a good basis for the subsequent evaluation and classification of rock burst disasters.
Carbon Emission Scenario Prediction and Peak Path Selection in China
Authors: Liu Xiaodie , Wang Xiangqian , Meng Xiangrui
Published: February 2023

Due to the emission of carbon dioxide and other greenhouse gases, the global climate is warming. As the world’s biggest emitter of carbon emissions, China faces a more severe challenge in reducing carbon emissions than developed countries. A reasonable prediction of the carbon peak in China will help the government to formulate effective emission reduction paths. This paper analyzes the changes in carbon emissions in China from 2004 to 2020, uses the STIRPAT model and scenario analysis method to predict carbon emissions from 2021 to 2030, and then calculates the carbon efficiency during carbon peaking to select the most effective carbon peak path for China. The results show that China’s carbon emissions increased year by year from 2004 to 2020. Under the baseline scenario, China is unlikely to reach its carbon peak before 2030. Under the regulatory scenarios, China can reach its carbon peak before 2030. The peak values from high to low are seen with the rapid development-weak carbon control scenario, rapid development-intensified carbon control scenario, slow development-weak carbon control scenario and slow development-intensified carbon control scenario, respectively. Correspondingly, China will peak its carbon emissions in 2029, 2028, 2028 and 2028, respectively, according to these scenarios. The carbon efficiency under the rapid development-weak carbon control scenario is the highest, which means that accelerating the growth rate of population, GDP and urbanization while moderately carrying out the transformation of industrial structure and energy structure is an effective way to achieve the goal of “carbon peak by 2030”.
3-D Inversion of Gravity Data of the Central and Eastern Gonghe Basin for Geothermal Exploration
Authors: Zhao Jianwei , Zeng Zhaofa , Zhou Shuai , Yan Jiahe , An Baizhou
Published: February 2023

The Gonghe Basin is one of the most important regions for the exploration and development of hot dry rock geothermal resources in China. However, there is still some controversy about the main heat source of hot dry rock geothermal resources in the Gonghe Basin. Combined with previous research results including three-dimensional magnetotelluric imaging and linear inversion of Rayleigh wave group and phase velocity result, we obtained a high-resolution underground spatial density distribution model of the Gonghe Basin based on satellite gravity data by using 3-D gravity focusing inversion method. According to the results, there are widely distributed low density anomalies relative to surrounding rock in the middle crust of the study area. The low-density layer is speculated to be a low-velocity, high-conductivity partial melting layer in the crust of the Gonghe Basin. The inversion result confirms for the first time the existence of a partial melt layer from the gravity point of view, and this high temperature melt layer may be the main heat source of the hot dry rock geothermal resources in the Gonghe Basin. It can provide a new basis for further research on the genesis of the hot dry rock geothermal system in the Gonghe Basin.
Telemental Health and Diverse Populations amid COVID-19
Authors: Yu Jiadong , Bekerian D. A.
Published: February 2023

Telemental health is defined as the delivery of psychological and mental health services via telecommunication technologies, including telephone-delivered therapy, videoconferencing, and internet-delivered programs. Research indicates that telemental health services are as effective as in-person services, and a dramatic increase in the use of telemental health has been observed during COVID-19. However, there are still persistent challenges and concerns about mental health providers’ competencies, clients’ data privacy, and legal and regulatory issues during this pandemic. Additionally, disparities in the use of telemental health services with diverse populations, based on factors such as age, gender, ethnicity, socioeconomic status, language, and culture, have been identified during this pandemic.
Impact of Polarization Reversal during Photoelectrocatalytic Treatment of WWTP Effluents
Authors: Collivignarelli Maria Cristina , Carnevale Miino Marco , Caccamo Francesca Maria , Abbà Alessandro , Bestetti Massimiliano , Franz Silvia
Published: February 2023

Photoelectrocatalysis (PEC) has been already proposed as a polishing treatment for wastewater treatment plants (WWTPs) effluents. In this work, the impact of polarization reversal during PEC process has been studied and evaluated on the basis of the removal of organic substance and color, biodegradability of the matrix, and inactivation of the catalyst. Effluents were sampled from a full-scale WWTP and alternatively treated by electrochemical oxidation (EC), photolysis (PL), photocatalysis (PC), photoelectrocatalysis, and photoelectrocatalysis with reverse polarization (PECr). The efficiency and the kinetics of the process, in terms of removal of organic substance and color, were not affected by reverse polarization and very similar results were obtained by PEC and PECr. The biodegradability of the effluents strongly increased both by PECr (RSBR: 0.84 ± 0.07), and by PEC and PL (0.89 ± 0.11, and 0.78 ± 0.02, respectively). In the selected polarization reversal mode (100 s at −0.1 V every 500 s at 4 V, cell voltage), a similar photocurrent loss after PEC and PECr was observed, suggesting no effect on the activity of the TiO2 mesh. This study can serve as a base for future research on polarization reversal to optimize operation parameters and exploit the procedure to preventing fouling and inactivation of the catalyst.
Radial Growth Response of Siberian Pines to Climate Warming in the Sayan Mountains, Southern Siberia, Russian Federation
Authors: Yang Feiyu , Yan Yuqi , Liang Hanxue , Wang Minhuang , Kang Jian , Jiang Shaowei , Zhou Peng , Wang Zhou , Shishov Vladimir V. , Zhang Yaling , Huang Jianguo
Published: February 2023

Climate warming and subsequent drought are predicted to alter local forest production and carbon budgets, the sensitivity of which may be site- and species-specific. Although a warmer and drier climate often constrains tree growth, whether trees grown in cool, wet regions across the Siberian forest can in turn be promoted remains unknown. Here, we aimed to investigate the historical growth tendency of Siberian forests in the Sayan Mountain areas and to explore how climate interacts to regulate their growth. We used ring-width data from Siberian pine (Pinus sibirica Du Tour) sampled from three sites in this area to establish a regional chronology and calculate percentage growth change (%GC) over the past 250 years. Bootstrapped correlation analysis between the regional ring-width chronology and climatic factors indicates the mean air temperature, though not precipitation, is more often positively linked to the radial growth of Siberian pines. The %GC series shows that, from 1966 to 2006, the rising temperatures in May resulted in a significant increase in the radial-growth rate of Siberian pines (r = 0.47, p < 0.05). Our study suggests that the positive growth rate anomaly is more likely to occur as temperatures rise in Southern Siberia.
Bucking at Landing by a Single-Grip Harvester: Fuel Consumption, Productivity, Cost and Recovery Rate
Authors: Borz Stelian Alexandru , Secelean Vlad-Nicolae , Iacob Liviu-Mihai , Kaakkurivaara Nopparat
Published: February 2023

Operating at high efficiency is one of the prerequisites of sustainable forest operations. Typically, harvesters are designed to operate in tree felling and processing operations under the cut-to-length method. However, reasons such as limited business opportunities during the year may negatively affect the machine utilization rate. Coupled with high ownership costs, this results in economic sustainability problems. With this in mind, some practitioners have started to replace the traditional bucking operations conducted motor-manually at the landing with full mechanization using harvesters. This study evaluates the productive performance, fuel consumption, cost, and recovery rate in bucking wood at the landing by a single-grip harvester. A total of 27 bunches were taken into study, containing a total of 232 stems and stem parts, which were processed in 913 logs. A processing work cycle averaged 1.5 min but varied widely between 0.3 and 7 min. Dominant in the productive time were elements such as swinging to grab the stems, swinging to process, and piling the logs, which accounted for 86% of the productive time. Fuel consumption was estimated at 21 L/h and 0.78 L/m3, respectively. Efficiency was estimated at 0.047 PMH/m3, and productivity was estimated at 21.41 m3/PMH; the global recovery rate was 95%, and costs were in the range of 10 to 11 €/m3. Although there were attempts to develop dependence models of time consumption, efficiency, productivity, and recovery rate as functions of stem length, input volume, and the number of processed logs, this worked only for efficiency and productivity. The best-fitted models explained efficiency and productivity by power and linear equations, taking the input volume as a predictor. In addition to their practical application, the results of this study may be important for the planning and control of operations, for comparison to other ways of implementing the landing operations, or for optimizing larger systems.
Validation by SSRs of Morphometric Markers for Genetic Variability in Araucaria araucana (Molina) K. Koch
Authors: Nin Stefania , Antonetti Maurizio , Burchi Gianluca , Gori Massimo , Bini Lorenzo
Published: February 2023

Araucaria araucana is an important seed and timber-yielding tree that grows naturally in the tropical and subtropical regions of the Andes in Argentina and Chile, and has also been introduced as an ornamental species in Europe. Genetic diversity has been observed in A. araucana native populations, but there have been no prior studies on the genetic diversity estimates of this species introduced in Europe. On the other hand, assessment of the genetic variation in Araucaria populations occurring in Europe might be an important tool in the selection of appropriate germplasms for ornamental nursery production and breeding strategies. In this study, morphological and genetic diversity was analysed using a previously defined descriptor list and SSR molecular markers in four putative populations of A. araucana, individuated in the Pistoia Nursery District (Tuscany, Italy). In total, 26 morphological descriptors and 28 SSR primer pairs were used for a diversity assessment of specimens. Results provide evidence for genetic and morphological correspondence among the four putative Araucaria populations. PCA and cluster analyses based on morphological traits clearly revealed three distinct clusters of specimens. SSR primers yielded 68% polymorphic loci among the considered populations, and 18 of them displayed informativeness for population genetics, according to a Polymorphic Information Content value larger than 0.25. This marker set revealed significant genetic differentiation, and UPGMA analysis enabled separation of these populations on the basis of their genetic distances into three main groups, which largely overlapped with clusters in the dendrogram obtained from the morphological data. In particular, in both cluster diagrams, all accessions belonging to a specific population were well separated from all the others due to matrix distances and differences in the canopy density that are more similar to conifers such as spruce, pine, or fir. ANOVA analysis and the FST value indicated a large between-population genetic variation. The Mantel test suggested that genetic differentiation between the four studied populations was positively correlated with morphological distance (r = 0.141, p < 0.05). Thus, both morphological and genetic markers showed applicability across populations of different seed origins and proved suitable for the identification and characterization of A. araucana accessions.
Do Ectomycorrhizal Trees Select Ectomycorrhizal Fungi That Enhance Phosphorus Uptake under Nitrogen Enrichment?
Authors: Kuyper Thomas W. , Suz Laura M.
Published: February 2023

Globally, forests are impacted by atmospheric nitrogen (N) deposition, affecting their structure and functioning above and below ground. All trees form mutualistic root symbioses with mycorrhizal fungi. Of the two kinds of mycorrhizal symbioses of trees, the ectomycorrhizal (EcM) symbiosis is much more sensitive to N enrichment than the arbuscular mycorrhizal (AM) symbiosis. Due to increasing N deposition, significant declines in the richness and abundance of EcM fungal species and shifts in community composition and functional traits have been recorded. Under increasing N deposition, ectomycorrhizal forests usually show enhanced foliar mass fractions of N, reduced foliar mass fractions of phosphorus (P), and, consequently, an increasing imbalance in the foliar N:P stoichiometry, ultimately impacting tree performance. The question has been raised of whether, under conditions of high N deposition, EcM trees can select EcM fungi that are both tolerant to high N availability and efficient in the acquisition of P, which could to some extent mitigate the negative impact of N deposition on nutrient balances. Here we evaluate the literature for mechanisms through which certain EcM fungi could increase P acquisition under increased N loading. We find very little evidence that under N enrichment, EcM fungi that have on average higher P efficiency might be selected and thereby prevent or delay tree N:P imbalances. However, methodological issues in some of these studies make it imperative to treat this conclusion with caution. Considering the importance of avoiding tree N:P disbalances under N enrichment and the need to restore EcM forests that have suffered from long-term excess N loading, further research into this question is urgently required.
Soil Microbial Biomass and Community Composition across a Chronosequence of Chinese Cedar Plantations
Authors: Shen Ya , Xiong Shichen , You Chengming , Zhang Li , Li Yu , Hong Zongwen , Hu Yifan , Li Jing , Li Han , Wang Lixia , Liu Sining , Tan Bo , Xu Zhenfeng
Published: February 2023

Afforestation is one of the most important forestry practices, but its impact on soil microbial communities remains poorly understood. In this study, we sampled the soil from 0–15 cm and 15–30 cm soil depths of 7-, 13-, 24-, 33-, and 53-year-old Chinese cedar (Cryptomeria japonica var. sinensis) plantations. To investigate the effect of stand age on soil microbial communities and their potential drivers, we measured phospholipid fatty acids (PLFAs) and soil physicochemical properties. At the 0–15 cm soil depth, the biomass of total PLFAs and functional microbial groups such as bacteria (B), fungi (F), Gram-negative bacteria (GN), Gram-positive bacteria (GP), actinomycetes (ACT), and arbuscular mycorrhizal fungi (AMF) increased sharply in 7- to 13-year-old stands, but then gradually leveled off in older stands. On the other hand, the biomass of total PLFAs and functional microbial groups at the 15–30 cm soil depth peaked in the 33-year-old stand. The biomass of total PLFAs and functional microbial groups was strongly influenced by stand age and soil depth, and was significantly lower at the 15–30 cm soil depth than at the 0–15 cm soil depth except for the 7-year-old stand. The F/B and fungi/total PLFAs ratios of both soil depths were markedly lower in the 13-year-old stand than in the remaining four stand ages, while the proportions of the bacterial group (GP and GN) showed contrasting trends. The biomass of all functional microbial groups and the GP/GN ratio were mainly mediated by soil organic carbon (SOC) concentration and the soil organic carbon to total phosphorus (C/P) ratio at the 0–15 cm soil depth, but primarily affected by ammonium nitrogen (NH4+-N) concentration at the 15–30 cm soil depth. The F/B ratio of the two soil depths was prominently affected by nitrate nitrogen (NO3−-N) concentration. Our results highlighted that SOC concentration and mineral N (i.e., NH4+-N and NO3−-N) concentration mainly drove changes in the soil microbial biomass and community composition with stand age in Chinese cedar plantations, and that the 13-year-old stand may be the key period for management.
Estimation of Aboveground Biomass of Individual Trees by Backpack LiDAR Based on Parameter-Optimized Quantitative Structural Models (AdQSM)
Authors: Ruhan A , Du Wala , Ying Hong , Wei Baocheng , Shan Yu , Dai Haiyan
Published: February 2023

Forest aboveground biomass (AGB) plays a key role in assessing forest productivity. In this study, we extracted individual tree structural parameters using backpack LiDAR, assessed their accuracy using terrestrial laser scanning (TLS) data and field measurements as reference values, and reconstructed 3D models of trees based on parameter-optimized quantitative structural models (AdQSM). The individual tree AGB was estimated based on individual tree volumes obtained from the tree model reconstruction, combined with the basic wood density values of specific tree species. In addition, the AGB calculated using the allometric biomass models was validated to explore the feasibility of nondestructive estimation of individual tree AGB by backpack LiDAR. We found that (1) the backpack LiDAR point cloud extracted individual tree diameter at breast height (DBH) with high accuracy. In contrast, the accuracy of the tree height extraction was low; (2) the optimal parameter values of the AdQSM reconstruction models for Larix gmelinii and Betula platyphylla were HS = 0.4 m and HS = 0.6 m, respectively; (3) the individual tree AGB estimated based on the backpack LiDAR and AdQSM fit well with the reference values. Our study confirms that backpack LiDAR can nondestructively estimate individual tree AGB, which can provide a reliable basis for further forest resource management and carbon stock estimation.
A Wildfire Detection Algorithm Based on the Dynamic Brightness Temperature Threshold
Authors: Ding Yunhong , Wang Mingyang , Fu Yujia , Zhang Lin , Wang Xianjie
Published: February 2023

Satellite remote sensing plays an important role in wildfire detection. Methods using the brightness and temperature difference of remote sensing images to determine if a wildfire has occurred are one of the main research directions of forest fire monitoring. However, common wildfire detection algorithms are mainly based on a fixed brightness temperature threshold to distinguish wildfire pixels and non-wildfire pixels, which reduces the applicability of the algorithm in different space–time regions. This paper presents an adaptive wildfire detection algorithm, DBTDW, based on a dynamic brightness temperature threshold. First, a regression dataset, MODIS_DT_Fire, was constructed based on moderate resolution imaging spectroradiometry (MODIS) to determine the wildfire brightness temperature threshold. Then, based on the meteorological information, normalized difference vegetation index (NDVI) information, and elevation information provided by the dataset, the DBTDW algorithm was used to calculate and obtain the minimum brightness temperature threshold of the burning area by using the Planck algorithm and Otsu algorithm. Finally, six regression models were trained to establish the correlation between factors and the dynamic brightness temperature threshold of wildfire. The root-mean-square error (RMSE) and mean absolute error (MAE) were used to evaluate the regression performance. The results show that under the XGBoost model, the DBTDW algorithm has the best prediction effect on the dynamic brightness temperature threshold of wildfire (leave-one-out method: RMSE/MAE = 0.0730). Compared with the method based on a fixed brightness temperature threshold, the method proposed in this paper to adaptively determine the brightness temperature threshold of wildfire has higher universality, which will help improve the effectiveness of satellite remote fire detection.
Geranyl Diphosphate Synthase (CrtE) Inhibition Using Alendronate Enhances Isoprene Production in Recombinant Synechococcus elongatus UTEX 2973: A Step towards Isoprene Biorefinery
Authors: Yadav Indrajeet , Rautela Akhil , Gangwar Agendra , Kesari Vigya , Padhi Aditya K. , Kumar Sanjay
Published: February 2023

A hemiterpene, isoprene, is commercially produced from crude oil refining processes. As a result of fossil fuel depletion, isoprene production process development is gaining attention from recombinant cyanobacteria and other microbial systems for its industrial and biofuel applications. In the present study, a fast-growing and CO2-tolerant cyanobacteria, Synechococcus elongatus UTEX 2973, is engineered with Pueraria montana isoprene synthase (IspS) at neutral site I (NSI) in the genome of S. elongatus UTEX 2973. Furthermore, to enhance isoprene production a key enzyme (isopentenyl diphosphate isomerase, IDI) of the methyl-D-erythritol 4-phosphate (MEP) pathway is also overexpressed at neutral site III (NSIII). Wild-type and recombinant strains of S. elongatus UTEX 2973 (UTEX IspS and UTEX IspS.IDI) are studied for growth and isoprene production in the presence of an inducer (IPTG) and/or inhibitor (alendronate). Alendronate is used for the inhibition of geranyl diphosphate synthase (CrtE), downstream of the MEP pathway that catalyzes dimethylallyl diphosphate/isopentenyl pyrophosphate (DMAPP/IPP) condensation in the recombinant UTEX 2973 strains. The docking studies on SeCrtE (CrtE of Synechcoccus elongatus PCC 7942) and alendronate as an inhibitor have revealed that alendronate binds more tightly than IPP in the cavity of SeCrtE, with a higher number of intermolecular interactions and energy. The UTEX IspS strain has shown isoprene production below the limit of detection in the presence of an inducer and/or inhibitor; however, production studies using UTEX IspS.IDI showed a maximum production of 79.97 and 411.51 µg/g dry cell weight (DCW) in a single day in the presence of an inducer only and an inducer along with an inhibitor, respectively. The UTEX IspS.IDI strain produced 0.41 mg/g DCW of cumulative isoprene in the presence of an inducer and 1.92 mg/g DCW in the presence of an inducer as well as an inhibitor during six days of production. The yield improvement of isoprene is observed as being 4.7-fold by using the inhibition strategy, which is used for the first time in the recombinant cyanobacterial system. The average productivities of isoprene obtained from UTEX IspS.IDI are observed to be 2.8 μg/g DCW/h in the presence of an inducer and 13.35 μg/g DCW/h in the presence of an inducer as well as an inhibitor. This study provides a basis for the process development and yield improvement in isoprene production using a novel inhibition strategy in fast-growing recombinant cyanobacteria. Recombinant strains and metabolic pathway inhibition studies can be used in future attempts to photosynthetically produce hemiterpenes.
Effect of Co-Fermentation of Saccharomyces boulardii CNCM-I745 with Four Different Probiotic Lactobacilli in Coffee Brews on Cell Viabilities and Metabolic Activities
Authors: Chan Mei Zhi Alcine , Tan Li Ting , Heng Shermaine Wan Qing , Liu Shao Quan
Published: February 2023

Amid trends in non-dairy probiotic foods and functional coffees, it is timely to develop a high-count probiotic, fermented coffee beverage. Here, we aimed to enhance the viabilities of different probiotic lactobacilli strains in coffee brews by co-culturing with the probiotic yeast, Saccharomyces boulardii CNCM-I745. The growth, survival, and metabolic activities of Lactiplantibacillus plantarum 299v, Lactobacillus acidophilus NCFM, Limosilactobacillus fermentum PCC, and Lactobacillus gasseri LAC-343 were monitored when cultured individually or co-cultured in coffee brews with S. boulardii CNCM-I745. In co-cultures, all four probiotic lactobacilli maintained viable populations above 5.5 Log CFU/mL for at least 6 months at 4 and 25 °C. In contrast, singly cultured lactobacilli populations generally could not be detected beyond 3 months of storage at either temperature. In co-cultures, vigorous nutrient uptake (glucose, glutamate, and alanine) by the yeast limited lactic acid accumulation by the lactobacilli. Co-culturing also led to accumulations in yeast-derived metabolites (ethanol, 2/3-methylbutanol, 2,3-dimethoxystyrene, and decanoic acid), and lactobacilli-derived metabolites (4-ethylphenol), but the coffee bioactive components (caffeine, trigonelline, and 5-O-caffeoylquinic acid) and antioxidant capacities were maintained. Overall, S. boulardii CNCM-I745 is effective in enhancing the viabilities of probiotic lactobacilli from different species, which may be useful in developing shelf-stable probiotic foods.
Effect of Optimized Chitosan Coating Obtained by Lactic Fermentation Chemical Treatment of Shrimp Waste on the Post-Harvest Behavior of Fresh-Cut Papaya (Carica papaya L.)
Authors: Cabanillas-Bojórquez Luis Angel , Montes-Ávila Julio , Vega-García Misael Odín , López-Moreno Héctor Samuel , Castillo-López Ramón Ignacio , Gutiérrez-Dorado Roberto
Published: February 2023

Chitosan is a biopolymer obtained from shrimp waste mainly by a polluting chemical method. In this work, a less polluting biological-chemical method to obtain chitosan from this waste has been optimized; this method used a successive lactic fermentation and chemical process. Additionally, in this work, the effect of chitosan coating on the post-harvest behavior of fresh-cut papaya was studied as a practical application. A rotatable central composite design (CCRD) with two variables (fermentation time and total soluble solids of the fermentation medium) was used to optimize the chitosan extraction. The optimized conditions for chitosan extraction were 108 h and 8.74 °Brix. The optimized chitosan showed a high deacetylation degree of 83%, acceptable process yield of 2.03%, a low ash content of 0.23% and a molecular weight of 107.5 kDa. In addition, optimized chitosan decreased the loss of color and acidity, as well as the growth of microorganisms; it also increased the pH of minimally processed papaya slices without a statistically significant difference with that of commercial chitosan. Based on these results, optimized chitosan could be applied to other fruits as a coating to maintain their quality characteristics and inhibit microbial growth during the storage of fresh-cut fruits.
Development of a Simple and Robust Kinetic Model for the Production of Succinic Acid from Glucose Depending on Different Operating Conditions
Authors: Escanciano Itziar A. , Ladero Miguel , Santos Victoria E. , Blanco Ángeles
Published: February 2023

Succinic acid (SA) is one of the main identified biomass-derived chemical building blocks. In this work we approach the study of its production by Actinobacillus succinogenes DSM 22257 from glucose, focusing on the development and application of a simple kinetic model capable of representing the evolution of the process over time for a great diversity of process variables key to the production of this platform bio-based chemical: initial biomass concentration, yeast extract concentration, agitation speed, and carbon dioxide flow rate. All these variables were studied experimentally, determining the values of key fermentation parameters: titer (23.8–39.7 g·L−1), yield (0.59–0.72 gSA·gglu−1), productivity (0.48–0.96 gSA·L−1·h−1), and selectivity (0.61–0.69 gSA·gglu−1). Even with this wide diversity of operational conditions, a non-structured and non-segregated kinetic model was suitable for fitting to experimental data with high accuracy, considering the values of the goodness-of-fit statistical parameters. This model is based on the logistic equation for biomass growth and on potential kinetic equations to describe the evolution of SA and the sum of by-products as production events that are not associated with biomass growth. The application of the kinetic model to diverse operational conditions sheds light on their effect on SA production. It seems that nitrogen stress is a good condition for SA titer and selectivity, there is an optimal inoculum mass for this purpose, and hydrodynamic stress starts at 300 r.p.m. in the experimental set-up employed. Due to its practical importance, and to validate the developed kinetic model, a fed-batch fermentation was also carried out, verifying the goodness of the model proposed via the process simulation (stage or cycle 1) and application to further cycles of the fed-batch operation. The results showed that biomass inactivation started at cycle 3 after a grace period in cycle 2.
Exogenous Penicillium camemberti Lipase Preparation Exerts Prebiotic-like Effects by Increasing Cecal Bifidobacterium and Lactobacillus Abundance in Rats
Authors: Yang Yongshou , Jia Huijuan , Ando Chika , Kato Hisanori , Kumrungsee Thanutchaporn , Kato Norihisa , Kimoto Akiko , Fukuda Shinji , Kuroda Manabu , Nishio Kyoichi , Yamaguchi Shotaro
Published: February 2023

Penicillium camemberti is used in cheese production; however, its health benefits remain to be elucidated. We previously found that supplemental Aspergillus-derived lipase preparation exerts a strong bifidogenic effect in rats fed a high-fat diet. This study investigated the effects of the feeding of a diet containing a 0.2% or 0.4% Penicillium camemberti-derived lipase preparation (PCL) for two weeks on the cecal microbiota in rats. According to 16S rRNA gene sequencing analysis, both PCL supplements significantly (p < 0.05) affected the cecal microbial community. At the genus level, supplemental 0.4% PCL significantly increased the relative abundance of beneficial bacteria such as Bifidobacterium, Lactobacillus, and Collinsella (127-fold, 6-fold, and 193-fold increase, respectively). The abundance of these bacteria in the 0.2% PCL group was between that of the control and 0.4% PCL groups. Notably, the effects of supplemental 0.4% PCL on modulating the abundance of these bacteria matched the effects observed in studies on typical prebiotic oligosaccharides. PICRUSt analysis revealed that PCL supplements significantly modulated the relative abundance of bacterial genes associated with 27 metabolic pathways, some of which were similar to those reported for prebiotic oligosaccharides. This study provides the first evidence indicating that supplemental PCL exerts prebiotic-like effects by modulating the abundance of the gut microbiota.
Analysis of Ash Melting Temperatures of Agricultural Pellets Detected during Different Conditions
Authors: Čajová Kantová Nikola , Holubčík Michal , Trnka Juraj , Čaja Alexander
Published: February 2023

Agricultural and other residues are promising renewable energy sources. However, they can cause problems in combustion processes. One of these problems is also low ash melting temperatures. Except, the ash melting behavior can be impacted by many factors, such as ash preparation or used atmosphere. This article deals with comparing different atmosphere conditions during measurements of ash melting temperatures of three agricultural pellets: alfalfa, straw, and hay. The first one was oxidizing with compressed air and nitrogen. The second atmosphere was reduced with the air purge, and the last was only reduced, consisting of 60% carbon monoxide and 40% carbon dioxide. Differences between individual atmospheres were none, up to 9.8%. The most significant differences have appeared between oxidizing and reducing atmospheres. In general, the oxidizing atmosphere presents a less expensive way. More attention should be paid to the use of oxidizing atmosphere for applications in heat sources mainly due to its similarity to the combustion process. However, it would be suitable to realize more comprehensive research regarding ash preparation in different ways and with using of different types of fuel.
Isotopic Evidence of Population Connectivity at Multiple Life Stages for Larimichthys polyactis in the Southern Yellow Sea and East China Sea
Authors: Song Dade , Xiong Ying , Jiang Tao , Yang Jian , Kang Zhongjie , Zhong Xiaming , Liu Dongyan
Published: February 2023

Larimichthys polyactis, a typically oceanodromous species found across the East China, Yellow, and Bohai Seas, is one of the most ecologically and commercially important species in East Asian countries. Moreover, over the past decades, L. polyactis has experienced significant changes in its biological characteristics under long-term intensive fishing pressure, suggesting a need for urgent protection. A robust understanding of connectivity at the spatiotemporal scale is critical for the effective and thorough management of L. polyactis. In the present study, the otolith stable carbon (δ13C) and oxygen (δ18O) isotope ratios of four adult L. polyactis groups (Y-1–4) sampled in the southern Yellow and East China Seas (SYS and ECS) were determined at multiple life stages, including the larval dispersal period (core), overwintering period (A1), and one whole life cycle except the post-spawning period (A2). Dunn’s multiple comparison test showed that there was no difference among the Y-1, Y-2, and Y-3 groups in the otolith core and A1 zones (p > 0.05); the otolith δ13C and δ18O of the Y-4 group were significantly higher than those of the Y-3 group (p < 0.05) in the three analysed zones. In the otolith A2 zone, δ13C and δ18O of the Y-1 group were significantly higher than those of the Y-3 group (p < 0.05). Combined with the biplot of otolith δ13C and δ18O, the quadratic discriminant analysis (QDA) of the otolith core, A1 and A2 zones showed that: (1) in the otolith core zone, two dominant larval aggregations occurred, likely distributed in the coastal waters of northern Lvsi and Haizhou Bay fishing grounds (Y-4 and part Y-1/2 groups) and Zhoushan and southern Yangtze Estuary fishing grounds (Y-3 and part Y-1/2); (2) in the otolith A1 zone, two clear aggregations were separated by Y-4 and Y-1/2/3, suggesting two dominant groups overwintering in the SYS and ECS, respectively; and (3) in the otolith A2 zone, two dominant aggregations were separated by Y-4/1 and Y-2/3. In addition to the long-term larval dispersal process, the migratory route between spawning and overwintering grounds may be diverse, explaining the non-significant genetic differentiation of L. polyactis from different groups. Combining these results with those of previous studies on the life history of L. polyactis, a schematic map of the migratory routes is depicted providing important references for effective resource management.
Effect of Chronic Hydrogen Peroxide Exposure on Ion Transport in Gills of Common Carp (Cyprinus carpio)
Authors: Mou Yating , Li Bing , Hou Yiran , Jia Rui , Zhu Jian
Published: February 2023

High environmental hydrogen peroxide (H2O2) has been demonstrated to be toxic for fish. However, the response mechanism of fish to chronic H2O2 exposure is not yet well understood. Therefore, this study aimed to investigate the alteration in ion transport in gills and analyzed the potential response mechanism after chronic H2O2 exposure. The common carps were exposed to 0, 0.25, 0.50, and 1.00 mM of H2O2 for 14 days. The histopathological evaluation results indicated that H2O2 exposure caused incomplete gill filament structure. In the plasma, H2O2 exposure suppressed the potassium (K+) concentration but increased sodium (Na+) concentration. In the gills, the calcium (Ca2+) level was raised, but the K+ and chlorine (Cl−) levels were decreased after H2O2 exposure. After 14 days of exposure, H2O2 prompted the activities of Ca2+/Mg2+-ATPase and H+/K+-ATPase but suppressed Na+/K+-ATPase activity in the gills. Gene transcription analysis showed that the ion-regulation-related genes including nkaa and rhbg were downregulated after H2O2 exposure. In addition, H2O2 exposure upregulated the mRNA levels of cam and camk II, indicating that the Ca2+ singling pathway was activated. In conclusion, our data showed that chronic H2O2 exposure altered gill structure and disturbed ion transport, which further negatively affected the equilibrium of ions and osmotic pressure.
Assessment of Variability Sources in Grape Ripening Parameters by Using FTIR and Multivariate Modelling
Authors: Schorn-García Daniel , Giussani Barbara , García-Casas María Jesús , Rico Daniel , Martin-Diana Ana Belén , Aceña Laura , Busto Olga , Boqué Ricard , Mestres Montserrat
Published: February 2023

The variability in grape ripening is associated with the fact that each grape berry undergoes its own biochemical processes. Traditional viticulture manages this by averaging the physicochemical values of hundreds of grapes to make decisions. However, to obtain accurate results it is necessary to evaluate the different sources of variability, so exhaustive sampling is essential. In this article, the factors “grape maturity over time” and “position of the grape” (both in the grapevine and in the bunch/cluster) were considered and studied by analyzing the grapes with a portable ATR-FTIR instrument and evaluating the spectra obtained with ANOVA–simultaneous component analysis (ASCA). Ripeness over time was the main factor affecting the characteristics of the grapes. Position in the vine and in the bunch (in that order) were also significantly important, and their effect on the grapes evolves over time. In addition, it was also possible to predict basic oenological parameters (TSS and pH with errors of 0.3 °Brix and 0.7, respectively). Finally, a quality control chart was built based on the spectra obtained in the optimal state of ripening, which could be used to decide which grapes are suitable for harvest.
A Comprehensive Review of Pesticide Residues in Peppers
Authors: Shim Jae-Han , Eun Jong-Bang , Zaky Ahmed A. , Hussein Ahmed S. , Hacimüftüoğlu Ahmet , Abd El-Aty A. M.
Published: February 2023

Pesticides are chemicals that are used to control pests such as insects, fungi, and weeds. Pesticide residues can remain on crops after application. Peppers are popular and versatile foods that are valued for their flavor, nutrition, and medicinal properties. The consumption of raw or fresh peppers (bell and chili) can have important health benefits due to their high levels of vitamins, minerals, and antioxidants. Therefore, it is crucial to consider factors such as pesticide use and preparation methods to fully realize these benefits. Ensuring that the levels of pesticide residues in peppers are not harmful to human health requires rigorous and continuous monitoring. Several analytical methods, such as gas chromatography (GC), liquid chromatography (LC), mass spectrometry (MS), infrared spectroscopy (IR), ultraviolet–visible spectroscopy (UV–Vis), and nuclear magnetic resonance spectroscopy (NMR), can detect and quantify pesticide residues in peppers. The choice of analytical method depends on the specific pesticide, that is being tested for and the type of sample being analyzed. The sample preparation method usually involves several processes. This includes extraction, which is used to separate the pesticides from the pepper matrix, and cleanup, which removes any interfering substances that could affect the accuracy of the analysis. Regulatory agencies or food safety organizations typically monitor pesticide residues in peppers by stipulating maximum residue limits (MRLs). Herein, we discuss various sample preparation, cleanup, and analytical techniques, as well as the dissipation patterns and application of monitoring strategies for analyzing pesticides in peppers to help safeguard against potential human health risks. From the authors’ perspective, several challenges and limitations exist in the analytical approach to monitoring pesticide residues in peppers. These include the complexity of the matrix, the limited sensitivity of some analytical methods, cost and time, a lack of standard methods, and limited sample size. Furthermore, developing new analytical methods, using machine learning and artificial intelligence, promoting sustainable and organic growing practices, improving sample preparation methods, and increasing standardization could assist efficiently in analyzing pesticide residues in peppers.
Detection of Methicillin-Resistant Staphylococcus aureus among Foodborne Pathogenic Strains and Assessment of Their Adhesion Ability and Cytotoxic Effects in HCT-116 Cells
Authors: Merghni Abderrahmen , Hamdi Hiba , Ben Abdallah Marwa , Al-Hasawi Zaki M. , Al-Quwaie Diana A. , Abid-Essefi Salwa
Published: February 2023

Staphylococcus aureus is one of the high-threat pathogens equipped with a repertoire of virulence factors making it responsible for many infections in humans, including foodborne diseases. The present study aims to characterize antibiotic resistance and virulence factors in foodborne S. aureus isolates, and to investigate their cytotoxic effects in human intestinal cells (HCT-116). Our results revealed methicillin resistance phenotypes (MRSA) along with the detection of mecA gene (20%) among tested foodborne S. aureus strains. Furthermore, 40% of tested isolates showed a strong ability for adhesion and biofilm formation. A high rate of exoenzymes production by tested bacteria was also registered. Additionally, treatment with S. aureus extracts leads to a significant decrease in HCT-116 cell viability, accompanied by a reduction in the mitochondrial membrane potential (MMP), as a result of reactive oxygen species (ROS) generation. Thereby, S. aureus food poisoning remains daunting and needs particular concern to prevent foodborne illness.
Effects of Addition of Tea Polyphenol Palmitate and Process Parameters on the Preparation of High-Purity EPA Ethyl Ester
Authors: Ding Xuyang , Liu Fujun , Zheng Rui , Pei Xuechen , Wang Ziye , Zhou Dayong , Yin Fawen
Published: February 2023

High-purity eicosapentaenoic acid (EPA) ethyl ester (EPA-EE) can be produced from an integrated technique consisting of saponification, ethyl esterification, urea complexation, molecular distillation and column separation. In order to improve the purity and inhibit oxidation, tea polyphenol palmitate (TPP) was added before the procedure of ethyl esterification. Furthermore, through the optimization of process parameters, 2:1 (mass ratio of urea to fish oil, g/g), 6 h (crystallization time) and 4:1 (mass ratio of ethyl alcohol to urea, g/g) were found to be the optimum conditions in the procedure of urea complexation. Distillate (fraction collection), 115 °C (distillation temperature) and one stage (the number of stages) were found to be the optimum conditions for the procedure of molecular distillation. With the addition of TPP and the above optimum conditions, high-purity (96.95%) EPA-EE was finally obtained after column separation.
Toward Exploring and Utilizing the Nutritional and Functional Properties of Cereal Crops
Authors: Wang Yaqiong , Tu Min , He Guangyuan , Li Yin , Chang Junli
Published: February 2023

Cereal crops are of great importance in the development of human civilization and fall into two groups, major crops and minor crops [...]
Optimizing Levilactobacillus brevis NPS-QW 145 Fermentation for Gamma-Aminobutyric Acid (GABA) Production in Soybean Sprout Yogurt-like Product
Authors: Zhang Yue , Zhu Mengjiao , Lu Wenjing , Zhang Cen , Chen Di , Shah Nagendra P. , Xiao Chaogeng
Published: February 2023

Gamma-aminobutyric acid (GABA) is a non-protein amino acid with various physiological functions. Levilactobacillus brevis NPS-QW 145 strains active in GABA catabolism and anabolism can be used as a microbial platform for GABA production. Soybean sprouts can be treated as a fermentation substrate for making functional products. This study demonstrated the benefits of using soybean sprouts as a medium to produce GABA by Levilactobacillus brevis NPS-QW 145 when monosodium glutamate (MSG) is the substrate. Based on this method, a GABA yield of up to 2.302 g L−1 was obtained with a soybean germination time of one day and fermentation of 48 h with bacteria using 10 g L−1 glucose according to the response surface methodology. Research revealed a powerful technique for producing GABA by fermentation with Levilactobacillus brevis NPS-QW 145 in foods and is expected to be widely used as a nutritional supplement for consumers.
Development Control and Inactivation of Byssochlamys nivea Ascospores by Hyperbaric Storage at Room Temperature
Authors: Pinto Carlos A. , Galante Diogo , Espinoza-Suarez Edelman , Gaspar Vítor M. , Mano João F. , Barba Francisco J. , Saraiva Jorge A.
Published: February 2023

This study tested hyperbaric storage (25–150 MPa, for 30 days) at room-temperature (HS/RT, 18–23 °C) in order to control the development of Byssochlamys nivea ascospores in apple juice. In order to mimic commercially pasteurized juice contaminated with ascospores, thermal pasteurization (70 and 80 °C for 30 s) and nonthermal high pressure pasteurization (600 MPa for 3 min at 17 °C, HPP) took place, and the juice was afterwards placed under HS/RT conditions. Control samples were also placed in atmospheric pressure (AP) conditions at RT and were refrigerated (4 °C). The results showed that HS/RT, in samples without a pasteurization step and those pasteurized at 70 °C/30 s, was able to inhibit ascospore development, contrarily to samples at AP/RT and refrigeration. HS/RT for samples pasteurized at 80 °C/30 s evidenced ascospore inactivation, especially at 150 MPa, wherein an overall reduction of at least 4.73 log units of ascospores was observed to below detection limits (1.00 Log CFU/mL); meanwhile, for HPP samples, especially at 75 and 150 MPa, an overall reduction of 3 log units (to below quantification limits, 2.00 Log CFU/mL) was observed. Phase-contrast microscopy revealed that the ascospores do not complete the germination process under HS/RT, hence avoiding hyphae formation, which is important for food safety since mycotoxin development occurs only after hyphae formation. These findings suggest that HS/RT is a safe food preservation methodology, as it prevents ascospore development and inactivates them following commercial-like thermal or nonthermal HPP pasteurization, preventing mycotoxin production and enhancing ascospore inactivation.