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AbstractThe objective of this study was to determine the share of nitrogen Agronomic Efficiency/Productivity components (recovery/uptake efficiency; RE × physiological/utilization efficiency; PE) in a common intercropping system (maize-bean) which until the current research, there is no information about it. A split plots arrangement based on the randomized complete block design (RCBD) with three replications, was carried out during two successive cropping years. The main plot factor consisted of sole cultivation of maize and bean, row intercropping with ratios including 50%:50% (1 row of maize: 1 row of bean), 67%:33% (2 rows of maize: 1 row of bean), and 33%: 67% (1 row of maize: 2 rows of bean). Application and non-application of nitrogen (N) fertilizer (55 kg ha−1) were assigned to the subplots. In both species, when NUE was calculated based on the seed yield, the N utilization efficiency (NUtE) was higher in all treatments compared with NUtE based on the dry matter yield. Under the conditions of N application, the ratio of 50:50 of bean: maize intercropped had higher N uptake efficiency (NUpE) for both species. Moreover, the ratio of 50:50 had the highest total land equivalent ratio (LER) based on the seed yield (1.10), the NUpE (2.30%), and NUE indices (1.98 kg kg−1 and 2.02 kg kg−1 based on the seed yield and the dry matter yield, respectively). The ratio of 50:50 of bean: maize intercropped having the highest efficiency indices, can be a lasting solution to reduce N application and losses, improving its uptake efficiency. Reducing the excessive use of chemical N fertilizer increases the productivity of this input in agroecosystems and reduces costs and health concerns. [ABSTRACT FROM AUTHOR]

Comparing the absorption and translocation efficiency of the nutrients in olive cultivars can lead to the selection of cultivars with higher efficiency. This research was conducted with the aim of comparing the uptake and translocation capacity in 20 olive cultivars (12 domestic and 8 foreign) in a commercial orchard on calcareous soil in a randomized complete block design. Except for copper (Cu), leaf concentration of other elements was within the optimal range. In ʻAmphesis,ʼ high translocation (5.28%) and in ʻAmigdalolia,' high uptake capacity (12.6) caused an increase in leaf phosphorus (P). Leaf K in all cultivars was higher than the deficiency limit (0.77%). In none of the cultivars, leaf sodium (Na) concentration was higher than the toxicity limit (0.2%), it accumulated in the root of ʻZard-Aliabadʼ and ʻShengeh,ʼ and reduced in their leaf. Leaf iron (Fe) concentration of all cultivars was in the sufficient range (>63 mg kg−1) and the highest was in ʻGorgan-Aʼ and ʻZardʼ and the lowest in ʻKazeroon,ʼ ʻArbequinaʼ and ʻMission.ʼ Although the leaf Cu in ʻAmphesisʼ (4.32 mg kg−1) and ʻArbequinaʼ (4.03 mg kg−1) was above the sufficient limit, in the rest of the cultivars it was below this critical limit. The highest leaf manganese (Mn) concentration (61.35 mg kg−1) and the highest Mn translocation percentage (84.59) were in ʻFeshomi.ʼ Among these cultivars, ʻAmphesisʼ was higher than others in terms of P, potassium (K), Cu and zinc (Zn) leaf concentrations and ʻAmigdalolia in terms of P, K and Zn, and in most cases the reason for this is the higher translocation efficiency. [ABSTRACT FROM AUTHOR]

Cell-penetrating peptides (CPPs) are short chains of amino acids that have shown remarkable potential to cross the cell membrane and deliver coupled therapeutic cargoes into cells. Designing and testing different CPPs to target specific cells or tissues is crucial to ensure high delivery efficiency and reduced toxicity. However, in vivo/in vitro testing of various CPPs can be both time-consuming and costly, which has led to interest in computational methodologies, such as Machine Learning (ML) approaches, as faster and cheaper methods for CPP design and uptake prediction. However, most ML models developed to date focus on classification rather than regression techniques, because of the lack of informative quantitative uptake values. To address these challenges, we developed POSEIDON, an open-access and up-to-date curated database that provides experimental quantitative uptake values for over 2,300 entries and physicochemical properties of 1,315 peptides. POSEIDON also offers physicochemical properties, such as cell line, cargo, and sequence, among others. By leveraging this database along with cell line genomic features, we processed a dataset of over 1,200 entries to develop an ML regression CPP uptake predictor. Our results demonstrated that POSEIDON accurately predicted peptide cell line uptake, achieving a Pearson correlation of 0.87, Spearman correlation of 0.88, and r2 score of 0.76, on an independent test set. With its comprehensive and novel dataset, along with its potent predictive capabilities, the POSEIDON database and its associated ML predictor signify a significant leap forward in CPP research and development. The POSEIDON database and ML Predictor are available for free and with a user-friendly interface at , making them valuable resources for advancing research on CPP-related topics. Scientific Contribution Statement: Our research addresses the critical need for more efficient and cost-effective methodologies in Cell-Penetrating Peptide (CPP) research. We introduced POSEIDON, a comprehensive and freely accessible database that delivers quantitative uptake values for over 2,300 entries, along with detailed physicochemical profiles for 1,315 peptides. Recognizing the limitations of current Machine Learning (ML) models for CPP design, our work leveraged the rich dataset provided by POSEIDON to develop a highly accurate ML regression model for predicting CPP uptake. [ABSTRACT FROM AUTHOR]

: In order to explore the copper absorption characteristics of Anodonta woodiana, this study was based on the juveniles with higher Cu absorption efficiency as the experimental subjects. Five concentration gradients (2.0, 1.0, 0.1, 0.01 and 0.005 mg·L-1) of aquatic Cu were set according to its 96 h-EC50 to the mussels and China Fisheries Water Quality Standard (GB11607-89). This exposure experiment was conducted for 24 h. The results showed that the Cu absorption efficiency increased rapidly with the increase of exposure concentration, and the highest value was (0.69±0.11) μg/(g·h) in 2.0 mg·L-1 exposure group. However, the Cu removal rate showed a general decreasing trend, in which the removal rate of 0.005 mg·L-1 exposure group was the highest 84.8%, and the removal rate of 1.0 mg·L-1 exposure group was the lowest 28.9%. In conclusion, the high Cu uptake efficiency of juvenile A. woodiana indicates that it has a very high application potential in the prevention and control of heavy metal Cu pollution in freshwater fishery waters and in the development of model organisms for monitoring and evaluating the environmental Cu pollution in freshwater fishery waters. [ABSTRACT FROM AUTHOR]

In the present investigation the adsorption behavior of methylene blue (MB) dye from aqueous solution onto untreated chinar leaves powder (CLP) and chinar leaves biochar (CLB) has been studied. To find out optimum conditions, adsorption process was carried out by varying different parameters such as contact time, adsorbent dose, concentration, temperature, salts, and pH. The equilibrium adsorption data were subjected to different popular isotherms (Langmuir, Freundlich, and Temkin) and kinetic models (pseudo-first order, pseudo-second order and intra-particle diffusion model). The thermodynamic study was also done on the adsorption process. The maximum monolayer adsorption capacities for MB dye onto given adsorbents are 1.53 mg/g (CLP) and 1.02 mg/g (CLB). Also the values of RL and n suggest favourable adsorption process of MB dye onto CLP and CLB adsorbents. The pseudo-second order kinetic model is best obeyed by both the mentioned adsorbents for MB dye adsorption with R² value equal to 1. Thermodynamic study reveals that the adsorption process of MB dye is spontaneous, endothermic (CLB) and exothermic (CLP). At an equilibrium time of 20 min the uptake efficiency (> 99%) was recorded for both the low cost adsorbents (CLP and CLB) thus proved them fast and effective adsorbents for the removal of MB dye. [ABSTRACT FROM AUTHOR]

Summary: Spray‐induced gene silencing (SIGS) is an innovative and eco‐friendly technology where topical application of pathogen gene‐targeting RNAs to plant material can enable disease control. SIGS applications remain limited because of the instability of RNA, which can be rapidly degraded when exposed to various environmental conditions. Inspired by the natural mechanism of cross‐kingdom RNAi through extracellular vesicle trafficking, we describe herein the use of artificial nanovesicles (AVs) for RNA encapsulation and control against the fungal pathogen, Botrytis cinerea. AVs were synthesized using three different cationic lipid formulations, DOTAP + PEG, DOTAP and DODMA, and examined for their ability to protect and deliver double stranded RNA (dsRNA). All three formulations enabled dsRNA delivery and uptake by B. cinerea. Further, encapsulating dsRNA in AVs provided strong protection from nuclease degradation and from removal by leaf washing. This improved stability led to prolonged RNAi‐mediated protection against B. cinerea both on pre‐ and post‐harvest plant material using AVs. Specifically, the AVs extended the protection duration conferred by dsRNA to 10 days on tomato and grape fruits and to 21 days on grape leaves. The results of this work demonstrate how AVs can be used as a new nanocarrier to overcome RNA instability in SIGS for crop protection. [ABSTRACT FROM AUTHOR]

Background: Silicon (Si) is a multiple stress attenuator element in plants, however more research is needed to elucidate the actions in the plants defense system with low nutrition of manganese (Mn) for a prolonged period, and the attenuation mechanisms involved in the effects of Mn deficiency on energy cane with high fiber content. Thus, the objective of this study was to evaluate whether Si reduces the oxidative stress of the energy cane grown in low Mn in nutrient solution, to mitigate the effects of Mn deficiency, improving enzymatic and non-enzymatic defense, uptake of Mn the plant growth. Methods: An experiment was carried out with pre-sprouted seedlings of Saccharum spontaneum L. in a 2 × 2 factorial scheme in five replications in which the plants were grown under sufficiency (20.5 μmol L−1) and deficiency (0.1 μmol L−1) of Mn combined with the absence and presence of Si (2.0 mmol L−1) for 160 days from the application of the treatments. The following parameters were evaluated: accumulation of Mn and Si, H2O2, MDA, activity of SOD and GPOX, total phenol content, pigments, and quantum efficiency of PSII. Results: Mn deficiency induced the oxidative stress for increase the H2O2 and MDA content in leaves of plants and reduce the activity of antioxidant enzymes and total phenols causing damage to quantum efficiency of photosystem II and pigment content. Si attenuated the effects of Mn deficiency even for a longer period of stress by reducing H2O2 (18%) and MDA (32%) content, and increased the Mn uptake efficiency (53%), SOD activity (23%), GPOX (76%), phenol contents, thus improving growth. Conclusions: The supply of Si promoted great nutritional and physiological improvements in energy cane with high fiber content in Mn deficiency. The results of this study propose the supply of Si via fertirrigation as a new sustainable strategy for energy cane cultivation in low Mn environments. [ABSTRACT FROM AUTHOR]

Summary: Recent discoveries show that fungi can take up environmental RNA, which can then silence fungal genes through environmental RNA interference. This discovery prompted the development of Spray‐Induced Gene Silencing (SIGS) for plant disease management. In this study, we aimed to determine the efficacy of SIGS across a variety of eukaryotic microbes. We first examined the efficiency of RNA uptake in multiple pathogenic and non‐pathogenic fungi, and an oomycete pathogen. We observed efficient double‐stranded RNA (dsRNA) uptake in the fungal plant pathogens Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani, Aspergillus niger and Verticillium dahliae, but no uptake in Colletotrichum gloeosporioides, and weak uptake in a beneficial fungus, Trichoderma virens. For the oomycete plant pathogen, Phytophthora infestans, RNA uptake was limited and varied across different cell types and developmental stages. Topical application of dsRNA targeting virulence‐related genes in pathogens with high RNA uptake efficiency significantly inhibited plant disease symptoms, whereas the application of dsRNA in pathogens with low RNA uptake efficiency did not suppress infection. Our results have revealed that dsRNA uptake efficiencies vary across eukaryotic microbe species and cell types. The success of SIGS for plant disease management can largely be determined by the pathogen's RNA uptake efficiency. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is the mineral nutrient required in greater quantities by plants with deficiencies affecting crop production. Nitrate (NO3-) and ammonium (NH4+) are the inorganic N forms most readily available for plant uptake. We investigated the influence of ammonium and nitrate rates on growth, nutritional status, chlorophyll production, and nutritional efficiency in mahogany seedlings, grown in an Oxisol soil under greenhouse conditions. Treatments were five N rates (50, 100, 150, 200, and 400 mg dm−3 N) in ammonium and nitrate forms and control treatment (0 mg dm−3 N), in a factorial design with five replications. The plants were harvested for evaluation at 150 days after transplanting. N supply affected mahogany growth, mainly in the production of leaf tissue. The maximum economic efficiency of N rates for production of leaf tissue was around 190 mg dm−3 N. The ammonium supply enhanced leaf tissue production, with a 20% increase in leaf area and 15% in leaf dry matter compared to nitrate. Furthermore, the plants showed a preference for ammonium uptake in rates above 200 mg dm−3 N, which indicates that the preference for N form was dependent on the concentration of N in the soil. The ammonium supply enhanced nutritional status, mainly phosphorus, demonstrating high synergism on uptake of this nutrient. Conversely, a strong antagonism between nitrate and phosphorus uptake was observed. Thus, ammonium enhanced the growth and nutritional status of mahogany seedlings and must be prioritized in its fertilization. [ABSTRACT FROM AUTHOR]

This study aims to investigate radiolabeled Cefpodoxime Proxetil loaded chitosan (CP–CS) nanoparticles as nuclear imaging infection agent to Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). The encapsulation efficiency of Cefpodoxime Proxetil was found 82 ± 2%. CP and CP–CS nanoparticles were radiolabeled with Tc-99 m. The radiochemical purity of 99mTc–CP and 99mTc–CP–CS nanoparticles were determined by RTLC as 89 ± 3% and 94 ± 2% respectively. In vitro bindings of 99mTc–CP–CS nanoparticles to S. aureus and E. coli were found higher than 99mTc–CP bindings. [ABSTRACT FROM AUTHOR]

• Quantile regression was used to benchmark N productivity for potato crops. • The approach was also useful for analysing key components of N use efficiency. • It can provide un-bias treatment comparison and benchmarks for commercial crops. • Achievable recovery did not differ between methods of N application to potato. • Achievable N efficiencies of potato were comparable to other major crops. Sound nitrogen management seeks to ensure crop yield, quality and profit, while avoiding over-fertilization lead to excess reactive nitrogen entering the agro- ecosystem or under-fertilization leading to mining of soil organic matter. Here we advance a framework to compare crop nitrogen use efficiency (NUE) across genotypes, environments and management practices that accounts for the non-linearity between N supply and N uptake, and between N uptake and crop dry matter or yield. We used published data of potato dry matter production, yield, N uptake and N inputs to demonstrate the efficacy of simple frontier analysis to describe the upper limits of the first order components of nitrogen use efficiency. Using quantile regression, frontier curves were derived for the response of apparent nitrogen recovery to the rate of applied N and for the responses of crop dry matter and tuber yield (dry matter) to crop N uptake. The analysis captured the known higher NUE for tuber production of late relative to early maturing potato varieties. The maximum achievable apparent nitrogen recovery did not differ between N fertilization methods. Simple frontier analysis provides a practical approach to benchmark the nitrogen use efficiency of crops. This then allows valid comparison of treatments or commercial crops when there are differences in the amount of N applied or differences in crop dry matter accumulation. [ABSTRACT FROM AUTHOR]

Selenium (Se) biofortification via crops is one of the best strategies to elevate the daily Se intake in areas where soil Se levels are low. However, Se fertilizer recovery (SeFR) is low and most of the Se taken up accumulates in non‐harvested plant parts and returns to the soil with plant residues. A pot experiment with soil was undertaken to study the efficiency of inorganic Se (Na2SeO4) and Se‐enriched plant residues for biofortification, as well as to identify the bottlenecks in Se utilization by Brassica napus L. The soil was fertilized with Na2SeO4 (0 and 7 µg Se kg−1) or with Se in stem or leaf residues (0 and 7 µg Se kg−1). A treatment with autoclaved soil was included (0 and 7 µg kg−1 as Na2SeO4) to unravel the impact of microbial activity on Se uptake. The Se‐enriched plant residues produced a lower Se uptake efficiency (SeUPE) and SeFR than did inorganic Se, and soil autoclaving enhanced Se accumulation in the plants. The time required for decomposition seems to preclude crop residues as an alternative source of Se. Furthermore, B. napus had a limited capacity to accumulate Se in seeds. The study shows that the bottlenecks in Se biofortification appear to be its low bioavailability in soil and poor loading from the silique walls to seeds. Thus, improved Se translocation to seeds would be a useful breeding goal in B. napus to increase SeFR. [ABSTRACT FROM AUTHOR]

Safety and the quality of products rely on proper cleanliness procedures and good manufacturing practices in the production environment. The use of swabs for the collection of samples from surfaces has been a common practice in industries, medicine and forensic studies. To accommodate these different purposes, many varieties of swabs have been introduced into the market, and it is important to assess the performance of these swabs before incorporating into an environmental monitoring procedure. The overall effectiveness of a swab is determined by two factors: the number of bacteria that a swab can uptake from a surface and the number of picked-up bacteria the swab can elute into a releasing buffer. This study evaluated the uptake efficiency and release efficiency of four different commercially available swabs: CleanFoam (Texwipes, USA), FLOQSwabs (Copan diagnostic Inc., USA), Hydraflock swabs (Puritan medical products, USA), and Cotton swabs. Cotton swabs showed the highest uptake efficiency (96.5 ± 1.9%), whereas CleanFoam swabs (57.9 ± 20.3%) showed the least. Both flocked (FLOQSwabs and Hydraflock) swabs showed over 80% uptake efficiency. Releasing efficiency of swabs was tested with eight different releasing buffers. Cotton swabs displayed the lowest release efficiency with most of the tested releasing buffers. When employed with Tris HEPES, Tris MOPS, Tris TAPS, FLOQSwabs, and Hydraflock swabs exhibited releasing efficiency of over 75%. The overall efficiency of the swabs was determined using TAPS as the releasing buffer and the values obtained were 80.4 ± 9.8%, 54.7 ± 16.9%, 35.0 ± 12.7% and 25.2 ± 6.9% for Hydraflock swabs, FLOQSwabs, Cotton swabs and Cleanfoam swabs, respectively. • Different swabs sampled microorganisms on surfaces with varying efficiencies. • Best overall performance obtained with Hydraflock swabs and TAPS as the release buffer. • Choice of releasing buffer had no significant effect. [ABSTRACT FROM AUTHOR]

Efficient cashew plants in relation to nutrition may represent gains in growth and production, especially in low fertility soils. This study aimed to determine the accumulation, the uptake, transport, and utilization efficiencies in different cashew genotypes. Twelve genotypes were evaluated, 10 of the dwarf type, a common type, and a hybrid. The seedlings were grown in plastic pots filled out with organic substrate. Sixty days after sowing, the plants were collected for the determination of dry matter and macro and micronutrients concentrations. Nutrient accumulation in cashew follows the descending order: N > K > P > Mg > Ca > S > Fe > Mn > Cu > B > Zn. Overall, for all nutrients, plants from BRS 274 had the high accumulation and utilization efficiency; the CCP 06 and CCP 76 in uptake; and the CCP 76 and BRS 189 in transport. [ABSTRACT FROM AUTHOR]

Aims: As ammonium (NH4+) has been reported as the “preferred” mineral N source for sugarcane (Saccharum spp.), the predominant supply of NH4+ has been hypothesized as a means of increasing the 15N recovery and crop yield. We aimed to evaluate the 15N recovery by sugarcane as affected by 15N-NH4+ and 15N-NO3− addition.Methods: Under field conditions, 15N-labeled ammonium nitrate [labeling as 15NH4NO3 (15N-NH4+) and NH415NO3 (15N-NO3−)] and urea were surface-applied at a rate of 100 kg N ha−1. Under controlled conditions, sugarcane was grown in hydroponic medium (containing unlabeled N) until the maximum N demand period. Subsequently, plants received 15N-NH4+ or 15N-NO3− (as ammonium nitrate). Plants were then sampled at 1, 3, 7, and 15 d after fertilization (DAF) to estimate 15N recovery.Results: Under field conditions, the 15N recovery for urea was lower than that for ammonium nitrate, partly explained by ammonia volatilization, but there was no difference in N use efficiency between the two fertilizer N sources, as well as between 15N-NH4+ and 15N-NO3− supply. Under controlled conditions, however, 15N-NH4+ resulted in higher 15N recovery than 15N-NO3− until 7 DAF. Nevertheless, as 15N-NH4+ became depleted in the nutrient solution, 15N-NO3− was taken up more intensely by the crop. At 15 DAF, highest 15N recovery was detected in the roots and whole plant under 15N-NO3− supply.Conclusions: Although uptake of NH4+ is faster than NO3−, the so-called “preference” for NH4+ by the crop did not necessarily translate into higher 15N recovery. Therefore, we suggest that the term “preference” should be used with caution to avoid misinterpretation. [ABSTRACT FROM AUTHOR]

Permanent raised-bed is an alternative planting system for wheat (Triticum aestivum L.) in rain-fed areas. However, this system in monoculture conditions produces lower yields compared with wheat in rotation. Our objective was to estimate these yield differences as affected by nitrogen (N) use efficiency (NUE). Wheat in monoculture and in rotation with maize (Zea maysL.) was evaluated for eight years (2002–2009) with four N rates (0, 40, 80 or 120 kg ha−1). Yield response to N in monoculture was consistently lower than for wheat in rotation. Yield reduction in monoculture at low and high N rate was 81 and 99% attributed to NUE out of which 70 and 82% was due to the uptake efficiency (UPE) and 30 and 19% to the utilization efficiency (UTE), respectively. Total N uptake proved to be the parameter that needs to be improved to enhance wheat yield in monoculture. Abbreviations:NUE: nitrogen use efficiency; UPE: uptake efficiency; UTE: utilization efficiency; Ns: nitrogen supply; NDVI: normalized difference vegetation index [ABSTRACT FROM PUBLISHER]

Nitrogen use efficiency (NUE) is of great interest to wheat ( Triticum aestivum L.) breeders because it addresses the daunting prospect of feeding the burgeoning population under the constraints of limited land resources and a warming climate. In this study, we evaluated a 56 entry panel of SRW breeding lines and cultivars from the eastern US wheat region in 2014 for NUE and related traits. The 56-entry block was grown at Lexington and Princeton, KY at two N rates (0 and 112 kg ha −1 ) in a complete factorial design. We measured normalized difference vegetative index (NDVI), biomass, harvest index, N harvest index, N uptake efficiency, N utilization efficiency, post-anthesis N uptake, N remobilization efficiency and overall NUE. Breeders usually apply high rates of N fertilizer to their plots in order to maximize genetic yield potential. Our study indicates that without screening breeding lines in low N environments concurrently, it will not be possible to identify high NUE genotypes. Post-anthesis N uptake, was highly correlated with yield (r = 0.79) under high N, but heritability of this trait was close to zero. Heritability of NUE, on the other hand was moderately high (h 2 = 0.65). Five breeding lines ranked within the top 10 for NUE in both low and high N environments. NDVI was found to be both heritable and highly correlated with yield across N environments (R 2 = 0.78). Genome wide association studies of NUE and related traits revealed QTL associated with NUE (chromosome 2B), uptake efficiency (chromosome1B) and utilization efficiency (chromosomes 1A and 3A). In accord with other studies, these QTL are of small effect and will likely only be useful in genomic selection as opposed to marker-assisted selection. [ABSTRACT FROM AUTHOR]

This study investigated how spring nitrogen (N) application affects N uptake and growth performance in tall bearded (TB) iris 'Immortality' (Iris germanica L.). Container-grown iris plants were treated with 0, 5, 10, 15, or 20 mm N from 15NH415NO3 through fertigation using a modified Hoagland's solution twice a week for 6 weeks in Spring 2013. Increasing N rate increased plant height, total plant dry weight (DW), and N content. Total N content was closely related to total plant DW. The allocation of N to different tissues followed a similar trend as the allocation of DW. In leaves, roots, and rhizomes, increasing N rate increased N uptake and decreased carbon (C) to N ratio (C/N ratio). Leaves were the major sink for N derived from fertilizer (NDFF). As N supply increased, DW accumulation in leaves increased, whereas DW accumulation in roots and rhizomes was unchanged. This indicates increasing N rate contributed more to leaf growth in spring. Nitrogen uptake efficiency (NupE) had a quadratic relationship with increasing N rate and was highest in the 10 mm N treatment, which indicates 10 mm was the optimal N rate for improving NupE in this study. [ABSTRACT FROM AUTHOR]

Cell penetrating peptides (CPPs) were developed as vehicles for efficient delivery of various molecules. An ideal CPP‐peptide should not display any toxicity against cancer cells as well as healthy cells and efficiently enter into the cell. Because of the cationic nature and the intrinsic vector capabilities, these peptides can cause cytotoxicity. One of the possible reasons for toxicity of CPPs is direct translocation and consequently, pore formation on the plasma membrane. In this study it was demonstrated that interaction of poly‐glutamate with CPP considerably reduced their cytotoxicity in A549 cell. This strategy could be useful for efficient drug delivery mediated by CPP. [ABSTRACT FROM AUTHOR]

The aim of this work was to compare Cr(III) and Cr(VI) removal kinetics from water by Pistia stratiotes and Salvinia herzogii. The accumulation in plant tissues and the effects of both Cr forms on plant growth were also evaluated. Plants were exposed to 2 and 6 mg L−1of Cr(III) or Cr(VI) during 30 days. At the end of the experiment, Cr(VI) removal percentages were significantly lower than those obtained for Cr(III) for both macrophytes. Cr(III) removal kinetics involved a fast and a slow component. The fast component was primarily responsible for Cr(III) removal while Cr(VI) removal kinetics involved only a slow process. Cr accumulated principally in the roots. In the Cr(VI) treatments a higher translocation from roots to aerial parts than in Cr(III) treatments was observed. Both macrophytes demonstrated a high ability to remove Cr(III) but not Cr(VI). Cr(III) inhibited the growth at the highest studied concentration of both macrophytes while Cr(VI) caused senescence. These results have important implications in the use of constructed wetlands for secondary industrial wastewater treatment. Common primary treatments of effluents containing Cr(VI) consists in its reduction to Cr(III). Cr(III) concentrations in these effluents are normally below the highest studied concentrations in this work. [ABSTRACT FROM PUBLISHER]

[Display omitted] • P limitation increased Se uptake efficiency in Nannochloropsis oceanica. • Higher Se uptake efficiency led to higher Se toxicity. • Se accumulation was positively correlated with cell growth. • P 200 and Se 5 were considered the optimal concentrations for Se-enrichment. Microalgae are considered an efficient accumulator and promising source of Se for feed additive purposes. This study aimed at investigating, for the first time, the effect of phosphorus limitation on Se accumulation and uptake efficiency in N. oceanica. A range of phosphorus concentrations (0–2470 µM) were tested in either the presence or absence of sodium selenite (0, 5, 30 µM). Se accumulation was increased up to 16-fold and Se uptake efficiency was increased up to 3.6-fold under phosphorus growth-limiting concentrations. N. oceanica was then cultivated in a 1.8 L flat-panel photobioreactor in batch operation under two phosphorus growth-limiting concentrations (250 and 750 µM) where the accumulation of Se in the microalgal biomass, as well as its presence in the spent medium were analysed. This study is the first to investigate the effect of phosphorus limitation for increasing Se accumulation in microalgae, and to prevent the release of Se in wastewater. [ABSTRACT FROM AUTHOR]

Cell-penetrating peptides (CPPs) have proven their potential as an efficient delivery system due to their intrinsic ability to traverse biological membranes and transport various cargoes into the cells. In the present study, we have identified novel natural protein-derived CPPs using an integrated ( in silico and experimental) approach. First, using bioinformatics approach, arginine-rich peptide segments were extracted from SwissProt proteins and their cell-penetrating properties were predicted. Finally, eight peptides were selected and their internalization was validated using experimental techniques. Laser scanning confocal microscopy and flow cytometry confirmed that seven out of eight peptides were internalized into live cells with varying efficiencies without significant cytotoxicity. Three peptides have shown higher internalization efficacy than TAT peptide, the most widely used CPP. Among these three peptides, one peptide (P8), derived from voltage-dependent L-type calcium channel subunit alpha-1D, was able to accumulate inside in a variety of cell types very efficiently through a rapid dose-dependent process. Further, experiments involving inhibition with various endocytic inhibitors along with co-localization studies indicate that the uptake mechanism of P8 is macropinocytosis, a fluid-phase endocytosis process. In addition, competitive inhibition with heparin revealed the involvement of cell-surface proteoglycans in P8 uptake. In summary, the present study provides evidence that an integrated in silico and experimental approach is an effective strategy for the identification of novel CPPs and CPPs identified in the present study have promising perspectives for future drug delivery applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • We present a novel stacking approach called MLCPP 2.0 that yields improved and robust predictions of cell penetrating peptides and their uptake efficiency based on peptide sequence information. • We evaluated seven different classifiers and 17 different feature encodings to identify the optimal baseline models and classifier individually for cell-penetrating peptide prediction and uptake efficiency prediction. • MLCPP 2.0 is shown to perform better than publicly available state-of-the-art predictors in a comprehensive benchmarking test. • MLCPP 2.0 is implemented as an online webserver, which can be accessed at https://balalab-skku.org/mlcpp2. Cell-penetrating peptides (CPPs) translocate into the cell as various biologically active conjugates and possess numerous biomedical applications. Several machine learning-based predictors have been proposed in the past, but they mostly focus on identifying only CPPs. We proposed a two-layered predictor in 2018 in order to predict CPPs and their uptake efficiency simultaneously. While MLCPP has gained widespread access to research, further improvements are needed to enhance its practical application. A new version of MLCPP is presented in this study called MLCPP 2.0, an interpretable stacking model that identifies CPPs and their strength of uptake efficiency. We updated the benchmarking dataset, explored 17 different sequence-based feature encoding algorithms, and used seven different conventional machine learning classifiers. With multiple 10-fold cross-validation, we constructed 119 baseline models whose predicted probability values were merged and treated as a new feature vector. In a systematic way, a feature set and a classifier are identified that are optimal for predicting the CPP and uptake efficiency separately. The MLCPP 2.0 model achieved outstanding performance on the independent test set, significantly outperforming the existing state-of-the-art predictors. Hence, we expect that our proposed MLCPP 2.0 will facilitate the design of hypothesis-driven experiments by enabling the discovery of novel CPPs. MLCPP 2.0 is freely accessible at https://balalab-skku.org/mlcpp2/. [ABSTRACT FROM AUTHOR]

The effects of different concentrations of P and N, added separately or combined, on the Cr(III) accumulation capacity ofP. stratioteswere studied.Plants and pond water with the addition of contaminant(s) were placed in plastic aquaria. Cr concentration was 5 mg L–1, while P and N concentrations were 5 mg L–1or 10 mg L–1. Nutrient addition significantly favoured Cr removal and enhanced Cr translocation to leaves. In Cr treatments a high detritus formation from loss of root biomass was observed probably due to its toxicity. Cr was mainly accumulated in the detrital fraction, whereas P and N were retained fundamentally in leaves. A toxic effect was observed in the Cr + P10 and Cr + N10 treatments. These results could be applied to enhance Cr removal efficiency of constructed wetlands using P. stratiotes, where nutrient enrichment could be attained by treating sewage together with the industrial effluents. [ABSTRACT FROM AUTHOR]

Background and aims: Phosphorus (P) is a mobile nutrient in the plant so growth depends on its internal remobilization and a plant's ability to respond to its availability in the growing media. This study was conducted to evaluate the influence of P status and rootstocks on the patterns of P uptake and remobilization in orange trees. Methods: Sweet orange trees on Cleopatra mandarin (CM) or Rangpur lime (RL) rootstocks were grown for nine months in nutrient solution (NS) that was either P-deficient (DNS) or was P-sufficient (SNS). After this period, half of the trees were reciprocally transferred between DNS and SNS (from D to S and S to D), while the others remained in their initial P availability. Results: Trees on RL had more shoot and root growth, accumulated more P and had greater efficiency of P absorption and transport to the shoot (PAE) than those on CM. The major source of P for growth was previously stored P even with an adequate current P supply to the roots. This suggested the dominance of P remobilization over P uptake and the requirement that trees had sufficient stored P to meet P demand of new growth. Trees on CM had greater concentrations of remobilized P in new shoots than trees on RL. Conclusion: Trees grafted on rootstocks less able to take up P (CM) were more dependent on the internal reserves of P for new growth than rootstocks with higher PAE (RL). [ABSTRACT FROM AUTHOR]

Faba bean (Vicia faba L.) is one of the most important food legumes grown in Morocco under rainfed conditions. This crop requires phosphorus (P) fertilizers to produce higher yields. However, many farmers use low quantities of P because of its cost and the risk of drought. Consequently, the use of varieties with high P use efficiency (PUE) can improve productivity and farmers' income under erratic conditions where the application of high amounts of P is not economically justified. The genetic variation of PUE among Moroccan faba bean varieties was studied under different levels of available phosphorus to orientate the choice of adapted varieties. Two experiments were conducted, under rainfed conditions, at the experiment station of Douyet (Morroco) in 2000–2001 (year 1) and 2002–2003 (year 2). In both years, four P treatments 0, 40, 80 and 120 kg P2O5 ha−1 as fertilizer and four faba bean varieties (G) were tested. In year 1, the varieties tested were Aguadulce, Defès, Karabiga and Lobab. The same varieties were used in year 2 with the exception of Aguadulce, which was replaced by a determinate genotype with smaller straw production. Results showed that the G effect on PUE was significant in year 1, but not in year 2. In the conditions of the moderate P availability (year 1), the variety Defes had the highest PUE and grain yield. Where P availability was lower (year 2), the highest PUE was reached by Karabiga; however, the difference with Defes was not significant. Data showed also that PUE was positively correlated with harvest index (HI) and phosphorus harvest index (PHI). In year 1, genotypic variation for PUE was mainly explained by phosphorus utilization efficiency; but not by phosphorus uptake efficiency. From this study, we can conclude that for rainfed conditions, the breeding strategy is to develop genotypes like Defes with high HI and improved PUE. [ABSTRACT FROM PUBLISHER]

Abstract: Wheat germ agglutinin (WGA) modified PEG–PLA nanoparticles (WGA–NP) have demonstrated its potential for enhancing delivery of peptides into brain following intranasal administration. However, the effect of ligand density is less well known. WGA density may affect nanoparticles uptake in nasal epithelial cells through ligand-receptor interactions, and the damage to nasal tissue since WGA showed cytotoxicity to cells in a dose-dependent manner. In this study, the effect of WGA density on WGA–NP was studied with regard to both the uptake and toxicity in vitro, using Calu-3 cells, which express a number of N-acetylglucosamine on their cell surface. Nanoparticles containing different WGA ligand densities were prepared by controlling the molar ratio of thiolated WGA to maleimide–PEG–PLA (WGA/maleimide) and particles properties were examined. With the increase of WGA/maleimide ratio, the particle size, WGA density and the hemoagglutination increased, while the conjugation efficiency decreased. The in vitro study showed markedly enhanced endocytosis of WGA–NP compared to NP in Calu-3 cells and significant inhibition of uptake in the presence of chitin. Cytotoxicity of WGA–NP increased gradually with the increase of molar ratio of WGA to maleimide, nanoparticles concentration and incubation time. WGA–NP showed the highest efficiency of uptake and a mild cytotoxicity when the molar ratio of WGA to maleimide was 1:10. These results suggest that WGA density plays an important role in both cellular uptake and toxicity of WGA–NP via a receptor-mediated mechanism. Therefore, to achieve a more rational approach of drug delivery system design, the surface density of the targeting moiety on the nanoparticles surface should be considered. [Copyright &y& Elsevier]

Abstract: The aim of this work was to assess the uptake efficiencies, the uptake and bioaccumulation kinetics and the toxic effects of Cr, Ni and Zn on Eichhornia crassipes. Plants were exposed to 1mgL−1 of each metal and sampled during 30 days. E. crassipes removed 81%, 95% and 70% of Cr, Ni and Zn, respectively. Metal removal from water involved a fast and a slow component. Metals were accumulated fundamentally by roots. Cr was scarcely translocated to aerial parts. In these tissues, Ni showed the highest accumulation amount while Zn presented the highest accumulation rate. Metal toxicity on the biomass was different among treatments. However, biomass did not decrease in any case. All the studied metals produced chlorophyll decrease. The root cross-sectional area (CSA) and vessel number increased and the root length decreased when plants were exposed to Zn. Despite the toxic effects, E. crassipes accumulated Cr, Ni and Zn efficiently. [Copyright &y& Elsevier]

This study compares the nitrogen (N) use efficiency of safflower and sunflower in pot experiments, as the putatively high nitrogen use efficiency of the former is not sustained. Safflower out-yielded sunflower at low N supply, while at ample supply the opposite was observed. Both species accumulated similar amounts of N per pot at equivalent N supplies, but safflower was a better N accumulator due to lower dry matter production. Safflower utilizes absorbed N more efficiently than sunflower to produce seed yield at suboptimal N supply in terms of efficiency ratio and utilization index, but the opposite holds true at optimal and high supply. Functional analysis of utilization efficiency for dry matter and seed production substantiated the higher efficiency of safflower. It is concluded that in terms of N utilization safflower represents a low input crop and outperforms sunflower with respect to seed yield on soils low in available N. [ABSTRACT FROM AUTHOR]

Exosomes are nanoscale lipid vesicles that play important roles in oncogenesis and tumor heterogeneity. Recently, more attentions have been attracted for the analysis of exosomes by using AuNPs-based nanoprobes due to their unique physicochemical properties. In this regard, the geometrical parameters of AuNPs have high impact on the performance for exosome sensing, whereas the related mechanistic studies have not been reported so far. Herein in this work, we symmetrically explored the size influence of DNA functionalized AuNPs on their uptake efficiency by exosomes, and found that the uptake efficiency was highly size-dependent. Based on these interesting discoveries, we developed AuNPs-based nanoprobes for the in-situ detection of miRNA in exosomes. The nanoprobe prepared using 5 nm AuNPs exhibits the highest sensitivity with a detection limit of 6.53 × 103 particles/μL, which is about 2 orders of magnitude lower than that of traditional 13 nm AuNPs. Furthermore, the nanoprobe based on 5 nm AuNPs was successfully used in clinical serum samples to differentiate cancer patients from healthy individuals. All these results advise that DNA-AuNPs can be easily tailored through size modulation to design functional nanoprobe with excellent exosome uptake properties and improved performance in exosome sensing applications. [Display omitted] • The influence of AuNPs size on the uptake efficiency of DNA-AuNPs by exosomes was first systematically explored. • A AuNPs-based nanoprobe was developed for the in-situ detection of miRNA in exosomes. • The nanoprobe was successfully used in clinical serum samples to differentiate cancer patients from healthy individuals. • DNA-AuNPs can be easily tailored through size modulation to design functional nanoprobe with excellent properties. [ABSTRACT FROM AUTHOR]

• Fe-deficiency and toxicity stress tolerance mechanisms in rice. • Genes/QTLs for Fe-deficiency, toxicity and biofortification. • Screening and breeding efforts for both the stresses. Soils of large areas of the globe are affected by deficiency or toxicity of iron (Fe), making it one of the major limitations to higher productivity of rice. Deficiency of Fe, an essential micronutrient for growth and development of rice, produces grain with low Fe-content. Consumption of low-Fe rice causes malnutrition affecting human health. Biofortification is an easy and low-cost way to enhance Fe content in rice, the staple food of more than half of the global population. Identification of relevant quantitative trait loci (QTLs) and genes controlling the stresses are needed for developing tolerant genotype(s). Fe deficiency is commonly observed in alkaline and aerobic soils, while toxicity is seen in low pH soils of lowland rice ecology. Rice plants cope up under deficiency or toxicity conditions through various morphological, physiological and differential gene expression strategies. Rice plant uses various transporter genes like OsNAS1 , OsNAS2, OsIRT1 , OsIRT2, OsNRAMP1, OsYSL15 and OsYSL16 under deficiency stress while OsIRT1 , OsFRO2, OsVIT1, OsVIT2, OsNRAMP6, OsNAAT1 , OsNAS3, OsNAC4, OsNAC5 and OsNAC6 under toxicity condition are involved for Fe homeostasis. Several QTLs including qFe3:1, qFe3:2, qFe7:1, qFe9:1, qFe9:2, qFe10:1, Fe11:1, qFe3.3 and qFe7.3 associated with grain-Fe content have been identified. Many Fe binding and transporters genes like OsZIP1 , OsHMA4 , OsACA2 , OsZIP2 , OsCNGC , OsZIP3 , OsZIP5 , OsZIP9 , OsHma2 , ABC transporter, OsNAS3, heavy metal transporter, Chy zinc finger and OsACA9 have been identified to improve grain-Fe content. Donor lines for grain-Fe content have been identified from rice germplasms showing even up to 147 μg g−1 in brown rice. Fe content in rice grain has been enhanced to many folds using ferritin genes of soybean and common bean, NAS gene and mugineic acid synthase genes (HvNAS1 and HvNAAT-A,- B or IDS3) of barley, nicotianamine transporter gene (OsYSL2) and nicotinamine synthase genes (OsNAS1 , OsNAS2 and OsNAS3) through transgenic approach. The paper analyses the mechanisms of tolerance to Fe-deficiency and toxicity, identification of genes/QTLs responsible for tolerance under the stresses and helping for biofortification, assesses the stress affected symptoms, reviews the screening and summarizes the efforts for breeding programs for improving tolerance to Fe-deficiency and toxicity in rice. [ABSTRACT FROM AUTHOR]

Traumatic spinal cord injury leads to neuronal damage and results in varying levels of functional impairment. Nanomaterial-based drug delivery systems provide potential for axon regeneration from specific neurons by crossing blood-brain barrier. In our work, we analyzed whether magnetic nanoparticles (MNPs) detrimentally affect outgrowth processes in primary dorsal root ganglion (DRG) neurons from embryonic chick. The DRG neurons were extracted from E9-12 chick embryos and dissociated. The dissociated DRG was treated with different concentrations of MNPs for 72 hours. Images were obtained and analyzed using a Nikon A1 confocal microscope system. Our study showed that the highest dose of MNPs applied was minimally toxic for DRG cells treated for 72 hours. We found that 72 hours of MNP treatment did not affect the number of neurites, branches and neurite length in DRG cells. We did not see any effect on the morphology of neurons after MNP treatment. Also, we used rat primary neurons to study the uptake efficiency of surface functionalized nanoparticles (SFNPs) by different cell types in mixed cortical culture. Primary rat cortical cells were extracted from P0-P2 rats and cultured on PDL coated plates. The cultured cells were treated with -NH2 and -COOH surface functionalized nanocarriers for 30 mins. After immunocytochemistry, images were obtained using a Nikon A1 confocal microscopy and analyzed. Uptake of a portion of our nanoparticles was seen in cortical neurons. Together, these results show the feasibility of nanocarriers for targeted drug delivery to encourage axon regeneration following nervous system damage. [ABSTRACT FROM AUTHOR]