Mature Stage Research Articles

Renewable energy communities: Democratically legitimate agents in governing the energy transition?

It is crucial that the energy transition enfolds democratically, to increase its legitimacy and improve its outcomes. Although practitioners and scholars increasingly point to renewable energy communities (RECs) as legitimate agents for governing a democratic energy transition, RECs' democratic practices are poorly understood, which challenges assumptions about their legitimacy. We therefore analyzed how and to what extent democratic legitimacy is being pursued and met by RECs in their governance of renewable energy generation projects. Our comparative case study examined four different RECs in Utrecht, The Netherlands. We found that three out of the four studied RECs broadly meet the principles of energy democracy in the initial, developing and implementation phase of their energy generation projects. Significant differences between principles and RECs were found, which refutes the simplistic general assumption that RECs are either fully democratically legitimate or are not democratically legitimate at all. In reality, RECs face several trade-offs between democratic principles, which arise from the different legitimacy needs related to the REC's stage of maturity and the type of energy source it uses. To overcome these trade-offs and uphold legitimacy internally as well as with various stakeholders, RECs strategically organize participation and decision making in different governance spaces and prioritize certain specific legitimacy principles over others. Combining the concepts of energy democracy and democratic legitimacy has brought novel theoretical insights to the fore, and we recommend other researchers to further bridge these distinct but related fields of study.

Effects of straw and roots removal on soil Cd availability and Cd accumulation in rice at different growth stages

It is argument on whether straw removal present a safer alternative compared to straw return or not where in paddy fields contaminated with cadmium (Cd). The objective of this study was to evaluate the impacts of varying levels of straw and roots removal on Cd uptake and accumulation, as well as on the growth of rice, Cd availability of soil at different growth stages, and the safety and nutritional value of brown rice were subject to assessment as well. A field experiment was conducted wherein rice stubble and roots were returned into the paddy field, serving as the control group (CK). The findings revealed that the removal of straw resulted in a decline in the availability of Cd in soil and the accumulation and uptake of Cd by rice plant. At the maturation stage of rice, the soil available Cd content and brown rice Cd content was significantly reduced by 40.39% and 24.79% under the treatment where 100% of rice straw and roots were removed. Moreover, there was a significant decline of 66.54% and 76.35% in dissolved organic carbon (DOC) and Cd concentrations respectively within soil pore water. This suggests that one crucial factor contributing to decreased Cd accumulation is the diminished complexation between DOC and Cd resulting from straw removal treatments. The removal of straw and roots had minimal impact on the nutritional components of brown rice, including essential amino acids. After the removal of straw and roots from the field, there was a reduction in hazard quotient (HQ) for rice consumers of varying genders and ages in the region by 17.71% to 24.95%, leading to a decrease in local ecological risk level from medium to slight. Therefore, the implementation of strategies such as removing straw could potentially lead to successful outcomes in reducing rice Cd uptake in paddy fields contaminated with this metallic element.

Impact of season and maturity stage on biochemical parameters of Averrhoa carambola fruits

The nutritional quality of fruits can be affected by changes in physiological indicators during fruit ripening, which is why it is important to identify the stage of maturity and the appropriate season for harvesting. Based on this observation, this study was carried out to evaluate the influence of the two different seasons and the stage of maturity on the nutritional parameters of Averrhoa Carambola. The results showed a significant effect (p<0.0001) of the two seasons and maturity stage on the biochemical parameters of A. carambola fruits. Ash contents and pH were significantly high in rainy seasons and at the ripe stage. Their values ​​were respectively (6.80±0.59%) and (3.54±0.27). Moisture and titratable acidity concentrations decreased significantly during maturation while total sugars, reducing and non-reducing sugars, and total soluble solids increased significantly during maturation. vitamin C and phenolic compounds were more abundant in the dry season and at the green stage. The values ​​were Vitamin C (15,869.64±0.03 mg/g), polyphenols (30.92±0.03 mg GAE/mg), flavonoids (30.59±0.28 mg EQ/g) and tannins (21-.02±0.01 mg GAE/g). This study suggests that there are differences in the biochemical parameters of starfruit between seasons depending on the maturity stage. The data provided useful information on the season and ideal stage of maturity for harvesting and their use in food products.

Causal role of immune cells in muscle atrophy: mendelian randomization study

Immune system and inflammation had a great influence on the progression of muscle atrophy. However, the causal relationship with specific immune cell traits remained uncertain. The aim of this study was to elucidate the genetic influences on these associations, providing insights into the underlying mechanisms of muscle atrophy. A bidirectional two-sample Mendelian randomization (MR) analysis was conducted to investigate the causal relationship between immune cell phenotypes and muscle atrophy. Data on immune cell phenotypes were obtained from a research cohort containing data on 731 immune cell phenotypes and data on muscle atrophy were sourced from a Finnish database. MR analysis was performed using the MR-Egger method, weighted median, inverse variance weighting, heterogeneity testing, sensitivity analysis, and multiplicity analysis, with results subjected to false discovery rate(FDR) correction. Additionally, the UK Biobank cohort was utilized as an external validation. A total of 31 immune phenotypes with causal relationships with muscle atrophy were identified, including various phenotypes of conventional dendritic cells, myeloid cells, T cells/B cells/natural killer cells, regulatory cells, and T cell maturation stages. Among them, 12 immune phenotypes were identified as exhibiting a positive causal relationship with muscle atrophy, while 19 immune phenotypes were demonstrated to have a negative causal association, highlighting the complex interactions between immune cells and muscle health. The results of the reverse MR analysis indicated that a negative correlation between muscle atrophy and CD28 on secreting Treg (OR = 0.9038, 95%CI:0.8308 ~ 0.9832, P = 0.0186). A significant positive correlation was revealed by external datasets between the CD25 on IgD + CD38- immune phenotype and the risk of muscle atrophy, which was consistent with the trend observed in the training group (OR = 1.1041, 95% CI: 1.1005–1.1076, P = 0.0263). No evidence of pleiotropy was observed, and the reliability of these findings was demonstrated by the leave-one-out analysis. The findings highlight significant correlations between certain immune cell features and muscle atrophy, providing potential targets for further investigation of immunological mechanisms and therapeutic interventions for this condition.

Analisis Diversifikasi, Merger, dan Akuisisi Perusahaan

This research aims to analyze the diversification, mergers and acquisitions of manufacturing companies in Indonesia. The research method used is descriptive qualitative analysis with a literature study approach. The results show that the diversification analysis was developed with various objectives including increasing growth when the existing market/product has reached a maturity stage, maintaining stability by spreading the risk of profit fluctuations, increasing credibility in the capital market, to avoid dependence on a single item or product in circulation. in the market, fulfill the wishes of unsatisfied consumers, increase the attractiveness or interest of consumers, increase sales turnover, increase profits by using the same ingredients, and prevent consumer boredom. Keywords: Diversification, Mergers, and Company Acquisitions.

Effects of plastic film mulching on soil microbial carbon metabolic activity and functional diversity at different maize growth stages in cool, semi-arid regions

IntroductionPlastic film mulching has been widely used to enhance soil hydrothermal conditions and increase crop yields in cool, semi-arid areas. However, its impact on soil microbial carbon metabolic activity and functional diversity during plant growth remains unclear despite their important roles in nutrient cycling and soil quality evaluation.MethodsThis study used the Biolog EcoPlate technique to investigate the dynamics and driving factors of soil microbial carbon metabolic activity and functional diversity at different maize growth stages following plastic film mulching.Results and discussionThe results revealed that film mulching significantly increased microbial carbon metabolic activities [represented by average well color development (AWCD)] by 300% at the seedling stage and by 26.8% at maturity but decreased it by 47.4% at the flowering stage compared to the control (without mulching). A similar trend was observed for the microbial functional diversity index. Redundancy analysis identified soil moisture (SM), soil temperature (ST), dissolved organic carbon (DOC), microbial biomass carbon (MBC), and bacteria amounts as the primary factors influencing changes in soil microbial carbon source utilization. The mulch treatment significantly increased SM at all growth stages, while its warming effect disappeared at the flowering stage. Soil DOC, MBC, and bacterial populations were notably higher under mulching at the seedling and maturity stages but lower at the flowering stage. Pearson correlation analysis showed that changes in SM, ST, DOC, MBC, and bacterial populations positively correlated with the utilization of all carbon source classes, AWCD, and functional diversity indexes after film mulching. Furthermore, maize grain yield and water use efficiency increased by 142 and 129%, respectively, following film mulching. In conclusion, plastic film mulching enhanced soil microbial carbon metabolic activity and functional diversity at the seedling and maturity stages, improving crop yields in cool, semi-arid areas. Furthermore, the decrease in soil carbon metabolic capacity at flowering stage highlights that supplementing soil carbon sources should be considered after continuous film mulching to sustain or enhance farmland productivity and soil quality.

Induction and maturation of somatic embryogenesis in mangaba tree a multipurpose Apocynaceae

This study reported the first results of in vitro somatic embryogenesis induction in Hancornia speciosa Gomes (mangaba tree, Apocynaceae). To induce callus, the TC accession leaf and nodal segments were cultivated in culture medium I (Murashige and Skoog; MS salts, putrescine, 45 µM 2,4-dichlorophenoxyacetic acid; 2,4-D and 22.19 µM 6-benzylaminopurine; BA). For the next stage (multiplication), the callus masses were sub-cultured into a culture medium II (MS salts, 22.62 µM 2,4-D and 22.19 µM BA). After 90 days, embryogenic calluses were inoculated to somatic embryo maturation medium culture III (MS salts, polyethylene glycol; PEG (0 and 2%) and BA (44.39 and 66.58 µM). Pro-embryos and somatic embryos in the maturation stage were assessed after 60 days. The rstatix package from R software with non-parametric tests (p < 0.05) were used to analysis data of experiments I and II. The Tukey’s test (p < 0.05) was performed on the data of experiment III. To induce and multiply embryogenic callus, 45 µM 2,4-D and 22.19 µM BA were efficient. More pro- and somatic embryo development were seen in the nodal explant cultured in the presence of 44.39 and 66.58 µM BA and 2% PEG. Putrescine does not promote the embryogenic masses of callus derived from leaf explants in the TC accession. Keywords: Hancornia speciosa Gomes, micropropagation, somatic embryo.

Strengthening ecosystems

Abstract The mission of THCS activities with respect to strengthening ecosystems is based on the understanding that the actual transformation of health and care systems is dependent on the ability of numerous actors to align their goals and actions so that they are complementary. At the same time, it is also true that the transformation takes place at national, regional and local levels, making activities and support at these levels essential for the success of THCS. Therefore, the focus lies on connecting and supporting the broad community and other stakeholders in developing ecosystem-wide approaches and creating awareness and urgency among ecosystem layers and components, thus serving as a platform for transformation. One strand of activities for strengthening ecosystems aims at identifying, analysing, describing and disseminating key learnings from successful transformative ecosystems (TE’s). TE’s are broad constellations of interacting organisations and people who are committed, and through aligned actions, able to reach joint, explicitly defined goals in long-term. Making not only the most successful TE’s but also the dynamics explaining their achievements visible, value is being added through three main routes. Firstly, the experiences are distributed widely on European arenas and platforms as well as through national, regional and local channels to inspire ecosystem building processes in earlier stages of maturity. Secondly, collaboration between identified forerunner ecosystems is supported to enable mutual peer-learning. Thirdly, the examples are used to give guidance and inspiration to consortia that are applying for or receiving THCS project funding. As strategic partners of the ecosystem strengthening activities, other work packages of the THCS programme as well as the THCS National Mirror Groups are of great importance.

Stereological study of organelle distribution in human mature oocytes

The ultrastructure of human oocytes has been described only qualitatively. To offer a precise organelle spatial distribution and organelle volume during the main maturation stages, we previously conducted stereological studies on prophase-I (GV) and metaphase-I (MI) oocytes, and here we present results on metaphase-II (MII) oocytes. Five donor oocytes from different donors were processed for transmission electron microscopy, and quantification of organelle distribution was performed using point-counting stereology. Statistical tests compared the means of the relative volumes occupied by organelles among oocyte regions. The most abundant organelles were elements of the smooth endoplasmic reticulum (SER), such as SER small vesicles, SER medium vesicles, SER large vesicles and SER isolated tubules, along with mitochondria, followed by SER tubular aggregates, cortical vesicles and lysosomes. Significant differences between oocyte regions were found for lysosomes, cortical vesicles and SER large vesicles. Comparisons of MII oocytes to previous findings in GV and MI oocytes evidenced specific patterns of organelle distribution and relative volumes. This final evaluation thus enables to track organelle spatial reorganization across oocyte stages, which, in addition to gathered knowledge, may be useful to assist in improvements of stimulation protocols, in-vitro maturation media and cryopreservation techniques.

Seed Oil Contents, Fatty Acid Compositions, and Gossypol Concentrations of Some Okra Landraces

ABSTRACTOkra has recently attracted attention owing to its superior tolerance to high temperatures, greater adaptation to poor soil conditions, and having a robust plant structure. The plant contains a high amount of oil and valuable fatty acids; however, the main restriction of using okra seeds as an oil crop results from its gossypol contents. The aim of this study was to determine the oil content of okra landraces and to evaluate its potential as an oil crop. For this aim, seed oil content, fatty acid compositions of cold‐pressed seed oil, and gossypol concentrations of fruit, oil cake, and seed oil were investigated in a core collection of 26 okra landraces, lines, and cultivars. Individual plants were harvested at the full maturity stage, and seeds were harvested and dried under 35°C for 2 days prior to oil extraction. Oil content, fatty acid composition, and gossypol content were analyzed by NMR, GC‐FID, and HPLC, respectively. The calibration coefficients (r2) of all the methods were determined to be > 0.99. The seed oil content of the samples ranged between 12.15% and 18.83%. Linoleic (42.01%), palmitic (31.65%), oleic (18.39%), and stearic acids (3.20%) were found to be the largest fraction of the fatty acids. The data matrix from 19 fatty acids and oil content was subjected to Principle Component Analysis (PCA). As a result, 6 principal components (PCs, eigenvalues > 1) explained 83.84% of total variance in the data set, with PC1 contributing 32.69% of the total. Gossypol contents of the fruit, oil cake, and seed oil fractions ranged between LOQ‐2.12, < LOQ‐7.01, and < LOQ‐62.46 mg/kg, respectively. In conclusion, okra may have the potential to be an alternative oil crop for food/feed purposes due to the presence of reasonable oil content, high‐quality fatty acid variations, and very low amounts of toxic gossypols, warranting further breeding and agronomic studies.

Environmental Impact and Decompsition of Polycyclic Aromatic Hydrocarbons (PAHs) in Urban Soils: Challenges and Future Directions

The rapid pace of urbanization and development has led to an increasing global concern over polycyclic aromatic hydrocarbons (PAHs) due to their persistent and widespread presence in the environment, posing significant threats to ecosystems and human health. PAHs originate from both natural and human-made sources and can be categorized based on their origin into pyrogenic, petrogenic, and biogenic products. Upon entering the environment, PAHs undergo various chemical and biological transformations, and their movement occurs through processes such as air-to-soil and soil-to-air transport. Composting, a green and cost-effective technology, offers a promising solution for PAH remediation. This process, which includes mesophilic, thermophilic, cooling, and maturing stages, can yield compost that is useful as fertilizer and soil amendment in agriculture. The success of composting depends on factors such as substrate bioavailability, oxygen levels, nutrient supply, and environmental conditions. While composting has shown effectiveness in reducing PAH levels, it is not without challenges, including the risk of weed infestation, greenhouse gas emissions, and odor pollution. The main obstacles in PAH remediation today are the limited bioaccessibility of PAHs and the insufficient focus on the formation of oxygenated PAHs during the process. Future research should address these challenges, particularly by improving PAH bioaccessibility and mitigating issues related to odor and greenhouse gas emissions.

Resistance of Chickpea (Cicer arietinum L.) Varieties to Gram Pod Borer (Helicoverpa armigera) in a Controlled Environment

The research was conducted within the controlled environment of the net house at the Faculty of Agriculture Science and Technology, AKS University, Satna (M.P.), during the Rabi season of 2023-24. Eight diverse chickpea (Cicer arietinum L.) genotypes, viz. JG-63, JG-130, L-2, JG-14, RAJ-128, Narendran-2, Annagiri and RVG-202, were systematically screened to evaluate their resistance to the gram pod borer (Helicoverpa armigera) under protected conditions. The study was meticulously designed using a Completely Randomized Design (CRD) with three replications to ensure robust statistical analysis. Throughout the critical vegetative, flowering and maturity stages, the larval population density of H. armigera was rigorously monitored across all genotypes at regular intervals. The comprehensive data analysis revealed that genotypes RAJ-128 and RVG-202 demonstrated superior resistance, exhibiting the lowest mean larval density of 0.25 and 0.29 larvae per 0.5 m², respectively, indicating their potential for integrated pest management in chickpea cultivation.

Reproductive biology of the rock oyster Striostrea prismatica in two populations of the Mexican Central Pacific

ABSTRACT The oyster Striostrea prismatica is a fishery-relevant species in the eastern tropical Pacific, particularly in the Mexican Central Pacific (MCP), and little is known about its reproductive cycle. Therefore, our study analysed gametogenesis, sex ratio, sexual maturity stages, shell height at first maturity, and condition index during 2014 and 2015 in El Tizate and La Victoria in the MCP. The sex ratio was significantly biased towards males at both sites, presumably due to ontogeny or fishing pressure. The highest condition index was observed between April and May in both years, while lower values were observed from September to December. The reproductive cycle in both sites was annual, with maturity and spawning from June to August and the degradation phase in August. The condition index showed a negative correlation with temperature and chlorophyll a in both sites: as a result, the period of maximum maturity and spawning coincided with the closure of the fishery in Mexico (June-August). Females had more significant shell height at first maturity than males at both sites, possibly associated with fishing pressure. The information from this study is a significant contribution, but it is necessary to extend the studies to populations further south and further north.

Mapping and cloning of pepper fruit color-related genes based on BSA-seq technology

Fruit color is an important qualitative trait that greatly influences the marketability of peppers. Fruit color can be divided into two categories. Green fruit color denotes commercial maturity, whereas ripe fruit indicates physiological maturity. Herein, segregation populations were created using the ‘D24’ with pale green in the green fruit stage, orange in the mature fruit stage, and ‘D47’ with green in the green fruit stage and red in the mature fruit stage. BSA-seq and genetic linkage map analysis revealed green fruit color was linked to (gyqtl1.1) on Chr1 and (gyqtl10.1) on Chr10, while mature fruit color was linked to Chr6. Using functional annotation, sequence, and expression analysis, we speculate that an SNP mutation in the CapGLK2 gene at the gyqtl10.1 interval could initiate premature termination of translation, thus yielding green to pale green fruits in D47. Conversely, the orange color in mature D24 fruits is due to the Indel-mediated premature termination of translation of the CapCCS gene. Our research offers a theoretical foundation for choosing different varieties of pepper fruit based on their color.

Sierra Negra, Galápagos: A resurgent-block basaltic caldera

Caldera resurgence is rare at mafic volcanoes. Here we consider the well-exposed resurgence at Sierra Negra caldera (Galápagos) to investigate how resurgence develops at a mafic system. Based on topographic and field analysis, the structure of the resurgence consists of an eastward-tilted block bounded by a fault-propagation fold activated by a steep inward-dipping reverse fault with dip decreasing toward the surface. Extension of the uplifted part of the reverse fault results from gravitational instability and is accommodated by horst-and-graben structures over a zone several hundred meters wide. Extension culminates in the main normal fault responsible for the inward tilt of the lava pile, forming a distinctive ridge. The resurgence results from spatially and temporally distinct unrest episodes, promoted by the shallow accumulation of large volumes of magma. Sierra Negra is the first documented example of piecemeal resurgence, as shown by the recent uplift episodes associated with eruptions in 2005 and 2018. The example of Sierra Negra suggests that the formation of resurgent blocks depends on the initial location of the feeding system, with non-centered feeding systems developing asymmetric (trapdoor) blocks. Finally, Sierra Negra demonstrates that mafic volcanoes without well-developed rift zones may promote resurgence when reaching a mature stage with significant amounts of cumulates, favoring shallow magma accumulation.

Optimizing Nitrogen Input Increased Yield and Efficiency in Maize-Soybean Strip Intercropping System

Optimizing nitrogen (N) fertilizer combination is a crucial measure to maximize yield and production efficiency in a maize-soybean strip intercropping system (MSSI). In this field experiment, six maize/soybean N input combinations (0 kg ha−1, F0; 255/30 kg ha−1, F1; 255/45 kg ha−1, F2; 255/60 kg ha−1, F3; 210/45 kg ha−1, F4; 300/45 kg ha−1, F5) were set in 2022 and 2023. The results indicated that optimizing N combination (maize/soybean, 255/45 kg ha−1) could synergistically increase yield and economic benefits. Path analysis results showed that the grain numbers in maize and soybean emerged as the most critical yield-affecting factors. Compared with F0, F5 showed the highest grain yield during the 2-year experiment, and the net return increased by 86.1% (F1), 133.3% (F2), 87.4% (F3), 104.7% (F4), and 128.3% (F5), respectively. Optimizing N input under F2 and F5 notably enhanced the leaf area index (LAI) of maize at the milk stage (R3) and soybean at the full pod stage (R4). Additionally, optimization of N distribution in maize stems at the tassel stage (VT) and soybean leaves at the initial flowering stage (R1) facilitated increased dry matter and N accumulation at the maturity stage, resulting in final land equivalent ratios (LER) of 1.44 and 1.55, respectively. Our results provide a more valuable field N combination for summer maize planting areas (sandy soil areas) in Huang-Huai-Hai and southern China, thus promoting the wider application of MSSI.

Optimal algae species inoculation strategy for algal-bacterial granular sludge: Sludge characteristics, performance and microbial community

The algal-bacterial granular sludge (ABGS) system is emerging as a promising technology for future wastewater treatment. This study assessed the impact of different algae species inoculation on granulation, performance, and microbial communities within ABGS systems. The experimental setup included single-species inoculations (Chlorella sp. (R1), Scenedesmus sp. (R2), and Desmodesmus sp. (R3)) and a mixed-species inoculation strategy (R4). Results revealed that R4 achieved the fastest completed granulation process (15 days) with the largest average granule diameter (772.93 μm) and highest physical strength (2.24 ± 0.26%) in the end of the experiment. The relative abundance of extracellular polymeric substances secreting bacteria of R4 maintained high level in whole operation time. Algae assimilation capacity and the abundance of functional bacteria can also influence removal performance. In mature stage, only the average effluent total nitrogen (3.15 ± 2.87 mg/L), total phosphorus (0.37 ± 0.27 mg/L), chemical oxygen demand (25.25 ± 2.98 mg/L) concentration in R4 was lower than that of Grade I discharge standard of municipal wastewater treatment plants in China. The best inorganic carbon utilization and lipid production ability were observed in R4 and R3, respectively. The choice of inoculated algae species was identified as a key factor for bacterial community dynamics. Overall, above results demonstrated that mixed algae species inoculation can be selected as the optimal algae inoculation strategy due to its excellent granulation, performance, and acceptable carbon utilization and lipid production.

Arsenic Uptake and Distribution in Green Pea Plants Under Arsenite and Arsenate Treatments

Soil arsenic (As) contamination is a global issue affecting regions worldwide. As in the soil is primarily present in inorganic forms, such as arsenite [As(III)] and arsenate [As(V)]. As is a microelement that is toxic to plants grown in As-contaminated soil. The aim of our study was to investigate the effects of increasing concentrations (0, 3, 10, 30, 90, and 270 mg kg−1) of As(III) and As(V) on the As content in green pea (Pisum sativum L.) and the distribution of As among different plant parts at four phenophases (the four-node stage, beginning of flowering, green ripening, and mature stage). Another aim was to determine the percentage of total soil As available to plants under different treatments. The results indicate that the developmental stage of the pea and treatment concentration significantly influence the distribution of As among plant organs. However, the differences between the effect of inorganic As forms were less pronounced. The amount of As absorbed by the whole test plant increased with higher treatment concentrations. In the case of As(III)-treatment, As amount in the whole plant increased from 0.170 µg to 7.31 µg (I. Phenophase); from 0.294 µg to 10.1 µg (II. Phenophase); from 0.435 µg to 31.6 µg (III. Phenophase); and from 0.697 µg to 36.1 µg (IV. Phenophase). As a result of As(V)-treatment, the whole plant’s As content increased from 0.170 µg to 8.94 µg (I. Phenophase); from 0.294 µg to 17.4 µg (II. Phenophase); from 0.435 µg to 29.7 µg (III. Phenophase); and from 0.697 µg to 58.5 µg (IV. Phenophase). The concentration of As accumulated by the plant also increased over time. The proportion of As absorbed by generative parts was much smaller than that absorbed by vegetative organs. The pea seeds generally accumulated less As (maximum 7%) than the pea pods (in some cases, this reached the 10%). As the total amount of As taken up by the plant increased, the proportion of As reaching the seeds generally decreased (from 5% to 0.3% in the case of As[III]-treatment, and from 5% to 0.1% in the case of As[V]-treatment). At treatment levels where the ability of the stem to retain As increased, a maximum of 1% of the total As absorbed by the plant was found in the seeds. Depending on the treatment, 3.82–5.69% [As(V)-treatments] and 3.9–6.07% [As(III)-treatments] of the total soil As were available to the plants. The difference in the ratio of the total As content to the soluble As content was more evident at higher treatment levels (≥30 mg kg−1). This value was typically lower for the As(V)-treatments.

Influence of Vine Decline Disease on the Amino Acid Metabolism of Watermelon Fruit

Vine decline (VD) is a recalcitrant syndrome of watermelon, melon, and other cucurbits, often associated with soil-borne pathogens such as Monosporascus cannonballus and characterized by root necrosis, leaf chlorosis, and wilting at the later stage of fruit maturation. The present study examined VD’s effects on watermelon fruits’ metabolism. The VD-affected watermelon fruits had significantly lower lycopene and total solid contents. Still, polyphenols content and total antioxidant activities were comparable with the controls, suggesting that VD inhibited the ripening processes but maintained defensive processes in the fruits. The VD fruits showed a lower calcium level than the controls, while the contents of other major nutrition minerals were not significantly altered. The VD fruits had a lower content of total amino acids, and their composition was characterized by an increase in the percentage fractions for several amino acids, including citrulline, which may reflect the physiological response to the VD-related water deficit condition. The principal component analysis distinguished amino acid profiles between the VD and control fruits, demonstrating that VD significantly influenced their amino acid metabolisms. The present study revealed that VD imposed characteristic impacts on the biochemical behaviors in the watermelon fruits.

Modelling post-chemotherapy stem cell dynamics in the bone marrow niche of AML patients

Acute myeloid leukemia (AML) is a stem cell-driven malignancy of the blood forming (hematopoietic) system. Despite of high dose chemotherapy with toxic side effects, many patients eventually relapse. The “7+3 regimen”, which consists of 7 days of cytarabine in combination with daunorubicin during the first 3 days, is a widely used therapy protocol. Since peripheral blood cells are easily accessible to longitudinal sampling, significant research efforts have been undertaken to characterize and reduce adverse effects on circulating blood cells. However, much less is known about the impact of the 7+3 regimen on human hematopoietic stem cells and their physiological micro-environments, the so-called stem cell niches. One reason for this is the technical inability to observe human stem cells in vivo and the discomfort related to bone marrow biopsies. To better understand the treatment effects on human stem cells, we consider a mechanistic mathematical model of the stem cell niche before, during and after chemotherapy. The model accounts for different maturation stages of leukemic and hematopoietic cells and considers key processes such as cell proliferation, self-renewal, differentiation and therapy-induced cell death. In the model, hematopoietic (HSCs) and leukemic stem cells (LSCs) compete for a joint niche and respond to both systemic and niche-derived signals. We relate the model to clinical trial data from literature which longitudinally quantifies the counts of hematopoietic stem like (CD34+CD38-ALDH+) cells at diagnosis and after therapy. The proposed model can capture the clinically observed interindividual heterogeneity and reproduce the non-monotonous dynamics of the hematopoietic stem like cells observed in relapsing patients. Our model allows to simulate different scenarios proposed in literature such as therapy-related impairment of the stem cell niche or niche-mediated resistance. Model simulations suggest that during the post-therapy phase a more than 10-fold increase of hematopoietic stem-like cell proliferation rates is required to recapitulate the measured cell dynamics in patients achieving complete remission. We fit the model to data of 7 individual patients and simulate variations of the treatment protocol. These simulations are in line with the clinical finding that G-CSF priming can improve the treatment outcome. Furthermore, our model suggests that a decline of HSC counts during remission might serve as an indication for salvage therapy in patients lacking MRD (minimal residual disease) markers.