Internal Concentration Research Articles

Blood and tissue levels of persistent organic pollutants and genetic susceptibility in patients with breast cancer

We investigated possible associations between the internal concentrations of POPs and correlations between blood and tumor tissue concentrations in patients who underwent surgery for breast cancer and breast reduction as controls. Genetic variations in CYP1A1, GSTP1, GSTM1, and GSTT1 and hOGG1 were evaluated to determine whether they represent risk factors for breast cancer. Certain POPs have been found to be associated with breast cancer development. GST-P1 polymorphism represented a significant risk for breast cancer with unadjusted OR. However, the GSTT1 null polymorphism represented a significant risk for breast cancer when OR adjusted for age and smoking status. CYP1A1 polymorphism was a significant risk factor for breast cancer, regardless of whether the OR was adjusted. These results suggest that exposure to certain POPs, GSTT1 and CYP1A1 polymorphisms, age, and smoking status are risk factors for breast cancer. In addition, the blood concentrations of some POPs represent surrogates for breast tissue concentrations.

Evaluation of Lippia scaberrima Sond. and Aspalathus linearis (Burm.f.) R. Dahlgren extracts on human CYP enzymes and gold nanoparticle synthesis: implications for drug metabolism and cytotoxicity

BackgroundMetabolism is an important component of the kinetic characteristics of herbal constituents, and it often determines the internal dose and concentration of these effective constituents at the target site. The metabolic profile of plant extracts and pure compounds need to be determined for any possible herb-drug metabolic interactions that might occur.MethodsVarious concentrations of the essential oil of Lippia scaberrima, the ethanolic extract of Lippia scaberrima alone and their combinations with fermented and unfermented Aspalathus linearis extract were used to determine the inhibitory potential on placental, microsomal and recombinant human hepatic Cytochrome P450 enzymes. Furthermore, the study investigated the synthesis and characterization of gold nanoparticles from the ethanolic extract of Lippia scaberrima as a lead sample. Confirmation and characterization of the synthesized gold nanoparticles were conducted through various methods. Additionally, the cytotoxic properties of the ethanolic extract of Lippia scaberrima were compared with the gold nanoparticles synthesized from Lippia scaberrima using gum arabic as a capping agent.ResultsAll the samples showed varying levels of CYP inhibition. The most potent inhibition took place for CYP2C19 and CYP1B1 with 50% inhibitory concentration (IC50) values of less than 0.05 µg/L for the essential oil tested and IC50-values between 0.05 µg/L-1 µg/L for all the other combinations and extracts tested, respectively. For both CYP1A2 and CYP2D6 the IC50-values for the essential oil, the extracts and combinations were found in the range of 1 – 10 µg/L. The majority of the IC50 values found were higher than 10 µg/L and, therefore, were found to have no inhibition against the CYP enzymes tested.ConclusionTherefore, the essential oil of Lippia scaberrima, the ethanolic extract of Lippia scaberrima alone and their combinations with Aspalathus linearis do not possess any clinically significant CYP interaction potential and may be further investigated for their adjuvant potential for use in the tuberculosis treatment regimen. Furthermore, it was shown that the cytotoxic potential of the Lippia scaberrima gold nanoparticles was reduced by twofold when compared to the ethanolic extract of Lippia scaberrima.

Efficient estimation of gas exchange and respiration kinetics in apple using pathlength-resolved GASMAS

Optimization of controlled atmosphere (CA) storage of pome fruit crucially depends on understanding of respiratory gas exchange. Different fruit properties are involved in describing gas transfer and respiration kinetics, which can vary between cultivars, fruit batches and individual fruit. Determination of these properties currently requires a combination of different time-consuming techniques and data analysis procedures. This study introduces a more efficient single method for O2 gas exchange characterization of fruit based on the non-destructive pathlength-resolved GASMAS (gas in scattering media absorption spectroscopy) technique. GASMAS was used to measure the absolute intercellular O2 concentration in fruit of different apple cultivars (Malus x domestica Borkh.) with distinct porosity including 'Jonagold', 'Braeburn', and 'Nicoter'. To resolve the ambiguity between variation in pathlength and O2 concentration inherent to GASMAS, the pathlength travelled through pores cavities was quantified through a second GASMAS measurement at the absorption line of H2O vapour. Dynamic experiments were then performed in which the fruit was subjected to varying external O2 concentrations while measuring the internal O2 response. The observed dynamic profiles of external and internal O2 concentration were fitted with a lumped -respiration model to estimate the effective mass transfer coefficient, maximum respiration rate and Michaelis Menten constant of intact fruit. The model showed a good fit (R2>0.95) with the measured data and reliable estimates for the model parameters. The proposed method provides a novel and more efficient way to estimate the gas exchange properties of fruit that are essential for optimizing CA storage conditions. Future challenges for the proposed method are with applications to other gasses such as CO2 and ethylene.

Adubação fosfatada, biofertilizante e Bacillus sp. no cultivo de amendoim sob estresse salino

ABSTRACT Peanut (Arachis hypogaea) is an important agricultural crop in Brazil, considered one of the most important oilseed crops cultivated. The use of fertilizer-solubilizing bacteria can mitigate salt stress. The objective of this study was to evaluate the gas exchange, growth, and water use efficiency of the peanut crop irrigated with brackish water under phosphate fertilization and inoculated with bacteria of the genus Bacillus sp. The experimental design used in this study was completely randomized, in a 4 × 2 × 2 factorial scheme, with 5 replicates, referring to the forms of fertilization (F1 - 0% phosphorus, F2 - 50% phosphorus, F3 - 100% phosphorus, and F4 - bovine biofertilizer), presence and absence of the inoculant and two levels of electrical conductivity of the irrigation water (ECw - 0.3 and 4.0 dS m-1). Fertilization with organic fertilizer (100% biofertilizer) and mineral fertilizer (50 and 100% phosphorus) associated with Bacillus sp. mitigated the damage caused by salt stress and promoted greater water use efficiency, chlorophyll index, internal CO2 concentration and stem diameter. The control treatment (without phosphate fertilization and without salt stress) and the application of Bacillus sp. promoted greater performance in net photosynthesis, transpiration rate, stomatal conductance, and plant height in peanut plants.

Morfofisiologia de feijão-caupi sob estresse salino e aplicação de nanobioestimulante de carbono na fase vegetativa

ABSTRACT Several technologies have been implemented to improve plant performance in irrigated crops, and one of them is the use of nanobiostimulants. Therefore, the aim of the present study was to explore the effects of applying different concentrations of a carbon-based biostimulant on the morphophysiology of cowpea plants subjected to varying electrical conductivities of irrigation water. The experiment was performed in a completely randomized design, in a 2 × 6 factorial scheme, with two electrical conductivities of irrigation water (ECw: 0.35 and 4.0 dS m-1) and six concentrations of nanobiostimulant applied through the leaves (0, 80, 160, 240, 320, and 400 mg L-1), with four replications. Growth and gas exchange variables were evaluated 31 days after sowing (V9 stage). Concentrations between 240 and 320 mg L-1 of carbon-based nanobiostimulant promoted greater increases in growth and physiological variables, but they caused decreases in non-photochemical quenching. Water electrical conductivity of 4.0 dS m-1 reduced the number of leaves (17.1%), stem diameter (10.0%), SPAD index (10.3%), net photosynthesis (10.9%), stomatal conductance (46.4%), transpiration (34.5%), instantaneous carboxylation efficiency (22.4%), and photochemical quenching (4.5%); in contrast, it increased the ratio between internal and ambient CO2 concentration (18.0%), leaf temperature (2.9%), water use efficiency (32.5%), and non-photochemical quenching (12.4%). Concentrations of 240 to 320 mg L-1 of the nanobiostimulant enhance the development and gas exchange of cowpea plants under non-stress conditions, whereas the concentration of 240 mg L-1 promotes the maximum increase in plant height under salinity.

Ácido salicílico reduz os efeitos prejudiciais do estresse salino em Tropaeolum majus

ABSTRACT Salt stress hampers the growth and physiology of nasturtium (Tropaeolum majus), due to biochemical, physiological, and anatomical disruptions. The application of salicylic acid stands as an alternative to alleviate the detrimental effects of salt stress, but studies on nasturtium are scarce. Thus, the aim of present study was to assess the effects of foliar application of salicylic acid on nasturtium cultivated under salt stress. The experiment followed a completely randomized design in a 3 x 3 factorial scheme, with 0 (no stress), 50 (moderate salt stress), and 100 (severe salt stress) mM of NaCl, and application of 0, 0.5, and 1 mM of salicylic acid, each with six replications. Growth (plant height, stem diameter, and number of leaves), gas exchange (stomatal conductance, photosynthesis, transpiration, internal CO2 concentration, intrinsic water use efficiency, instantaneous water use efficiency, and intrinsic carboxylation efficiency), as well as chlorophyll indices and chlorophyll a fluorescence were evaluated. Salt stress affected the variables analyzed in this study. The application of salicylic acid had a positive effect on mitigating the effects of severe salt stress, resulting in a significant increase in the number of leaves. The most effective dose was 1 mM, also leading to notable improvements in water use efficiency and photochemical efficiency. However, other combinations of salinity and salicylic acid reduced growth and gas exchange in nasturtium plants.

Exogenous application of ascorbic acid improves physiological and productive traits of Nigella sativa

For thousands of years, plants have been utilized for medicinal purposes. For its naturally existing antibacterial properties, Nigella sativa is one of the most researched herbs. A study was conducted during rabi 2020-21 at The University of Haripur in order to evaluate the potential of ascorbic acid as plant growth enhancer. Two concentrations of ascorbic acid i-e 350 μm and 400 μm were sprayed along with control and water only spray on Nigella sativa crop. The study was arranged in RCBD two factor factorial arrangement. Factor A: ascorbic acid concentrations along with control and water spray, factor B: Growth stages (Stage1 = 40 days after sowing, Stage 2 = 80 DAS, Stage 3 = 120 DAS, Stage 4 = 40 + 80 DAS, Stage 5 = 40 + 120 DAS, Stage 6 = 80 + 120 DAS, Stage 7 = 40 + 80 + 120 DAS). Crop was sown in first week of November. Results reviled that chlorophyll b content, fixed oil content, 1000 seed weight, grain yield, Photosynthetic rate (μ mole m−2s−1), Transpiration rate (mmole m−2s−1), photosynthetic water use efficiency, Internal CO2 concentration (Ci) of leaf tissue and Stomatal conductance (mmole m−2s−1) were significantly affected by ascorbic acid concentrations and stage of application. Crop growth rate increased by 19.88% and 17.29%, chlorophyll b by 12.3% and 11.2%, fixed oil by 11.7% and 9%, grain yield by 10.29% and 9.8%, harvest index by 4% and 5.7% photosynthetic rate by 33%, 20% and stomatal conductance by 24.24% and 24.25 with application of ascorbic acid @ 350 μm, over control and water spray respectively. On the basis of these results it is concluded that application of ascorbic acid at the rate of 350 μm, followed by ascorbic acid at the rate of 400 μm significantly improves black cumin (Nigella sativa) yield and production. Hence it is recommended to apply ascorbic acid at the rate of 350 μm at 40 + 80+120 days after sowing of Nigella sativa crop for obtaining maximum results.

Feasibility and challenges of high-pressure pressure retarded osmosis applications utilizing seawater and hypersaline water sources

Pressure retarded osmosis (PRO) harnesses salinity gradient energy through the mixing of freshwater and saltwater, addressing the demand for sustainable energy sources. PRO typically utilizes river water or secondary wastewater as the feed solution, paired with seawater reverse osmosis (SWRO) brine as the draw solution. However, the limited availability of low-saline water presents a significant obstacle to energy generation. Therefore, the feasibility of a high-pressure PRO process utilizing seawater as the feed solution and hypersaline water as the draw solution was assessed to generate sustainable blue energy. Seawater has the potential to achieve the maximum extractable Gibbs-free energy through high-pressure PRO by maximizing the feed/draw ratio. The performance of the high-pressure PRO was theoretically evaluated, resulting in a tenfold increase in specific energy production compared to conventional SWRO-PRO due to the higher feed/draw ratio. However, high hydraulic pressure increased the membrane structural parameter and further reduced water flux and power density due to significant internal concentration polarization. Nevertheless, the high-pressure PRO process can achieve a power density exceeding 84 W/m2 when the structural parameter remains below 100 μm. The implications of the high-pressure PRO were further discussed to advance the concept of a blue circular economy, enhance environmental resilience, and promote sustainability.

Uptake/depuration kinetics, bioaccumulation potential and metabolic transformation of a complex pharmaceutical mixture in zebrafish (Danio rerio)

Uptake and elimination kinetics, bioconcentration factors (BCFs), and metabolic transformation of 20 different pharmaceutically active compounds (PhACs), covering a wide range of therapeutic categories and physico-chemical properties, were studied using zebrafish (Danio rerio). The fish were exposed to the mixture of the selected PhACs at environmentally relevant concentrations similar to 10 µg L−1. The experiments were performed in semi-static conditions and comprised a 7-day uptake period followed by a 7-day depuration period. Most of the PhACs reached a concentration plateau within the 7-day uptake-phase which was followed by an efficient depuration, with the observed uptake (ku) and depuration rate constants (kd,) ranging between 0.002 and 3.752 L kg−1 h−1, and 0.010 to 0.217 h−1, respectively. The investigated PhACs showed low to moderate BCFs. The highest BCFs of 47.8, 28.6 and 47.6 L kg−1 were determined for sertraline, diazepam and desloratadine, respectively. A high contribution of metabolic products to the total internal concentration was observed for some PhACs such as codeine (69%), sulfamethoxazole (51%) and verapamil (87%), which has to be taken into account when assessing the bioconcentration potential. Moreover, most of the metabolites exhibited significantly longer half-lives in zebrafish than their parent compounds and affected the overall depuration kinetics.

Optimization of benzene exposure risk assessment: An integrated approach utilizing internal and external concentrations with a focus on biomarkers S-PMA & t, t-MA

In the majority of occupational settings within China, the concentrations of benzene are observed to fall markedly below the demarcated detection thresholds. Employing traditional risk assessment models, the presence of exceptionally low airborne benzene exposure concentrations may infuse heightened degrees of uncertainty. Consequently, the necessity arises to investigate risk assessment methodologies more apt for the prevalent exposure environment among employees. In the present study, a pharmacokinetic model premised on urinary benzene metabolites (S-PMA and t, t-MA) was employed to ascertain a more precise daily airborne benzene exposure concentration per individual. This value was integrated into the linear multistage model as the ‘internal exposure concentration’. In conjunction with the U.S National Environmental Protection Agency's (EPA) inhalation risk assessment model predicated on the external exposure concentration, the Singapore Ministry of Manpower's (MOM) model, and the linear multistage (LMS) model, the carcinogenic and non-carcinogenic effects of benzene were evaluated for 1781 benzene-exposed employees across 76 enterprises in Jiangsu Province. Findings suggest that in the linear multilevel model assessment, the cancer risk levels based on t, t-MA and S-PMA were higher in the printing and recording media reproduction industry, automobile manufacturing industry, general equipment manufacturing industry and the furniture manufacturing industry (median 2.842 × 10−4, 2.819 × 10−4, 2.809 × 10−4, and 2.678 × 10−4), which align more consistently with the actual benzene exposure circumstances of each industry's study participants, with overall risk levels calculated by the linear multistage model exceeding those of the EPA inhalation risk assessment model and the MOM model. This implies that the linear multistage model of internal exposure, based on the reciprocal of benzene biomarkers S-PMA and t, t-MA for airborne benzene exposure, presents enhanced sensitivity and suitability for the current occupational health risk assessment of workers. Without doubt, biomarker-based benzene exposure risk assessment emerges as the optimal choice.

PBPK modeling to support risk assessment of pyrethroid exposure in French pregnant women

BackgroundPyrethroids are widely used pesticides and are suspected to affect children's neurodevelopment. The characterization of pyrethroid exposure during critical windows of development, such as fetal development and prenatal life, is essential to ensure a better understanding of pyrethroids potential effects within the concept of Developmental Origins of Health and Disease. ObjectiveThe aim of this study was to estimate maternal exposure of French pregnant women from biomonitoring data and simulate maternal and fetal internal concentrations of 3 pyrethroids (permethrin, cypermethrin and deltamethrin) using a multi-substance pregnancy-PBPK (physiologically based pharmacokinetics) model. The estimated maternal exposures were compared to newly proposed toxicological reference values (TRV) children specific also called draft child-specific reference value to assess pyrethroid exposure risk during pregnancy i.e. during the in utero exposure period. MethodsA pregnancy-PBPK model was developed based on an existing adult pyrethroids model. The maternal exposure to each parent compound of pregnant women of the Elfe (French Longitudinal Study since Childhood) cohort was estimated by reverse dosimetry based on urinary biomonitoring data. To identify permethrin and cypermethrin contribution to their common urinary biomarkers of exposure, an exposure ratio based on biomarkers in hair was tested. Finally, exposure estimates were compared to current and draft child-specific reference values derived from rodent prenatal and postnatal exposure studies. ResultsThe main contributor to maternal pyrethroid diet intake is cis-permethrin. In blood, total internal concentrations main contributor is deltamethrin. In brain, the major contributors to internal pyrethroid exposure are deltamethrin for fetuses and cis-permethrin for mothers. Risk is identified only for permethrin when referring to the draft child-specific reference value. 2.5% of the population exceeded permethrin draft child-specific reference value. ConclusionsA new reverse dosimetry approach using PBPK model combined with human biomonitoring data in urine and hair was proposed to estimate Elfe pregnant population exposure to a pyrethroids mixture with common metabolites.

CO2 emission and physiological aspects of sugarcane ratoon as interactive functions of nitrogen and silicon applications

Sugarcane is the primary renewable energy source in Brazil, necessitating efficient and sustainable production practices. This study assessed the impact of nitrogen sources and their combination of silicon as foliar application on carbon dioxide (CO2) emissions and physiological characteristics of sugarcane cultivated in tropical environment. The experiment was conducted using the second sugarcane ratoon (variety CTC-04), as 2x5 factorial design, with two sources of N-fertilizer (urea and calcium ammonium nitrate - CAN, association with DMPSA − 3,4-dimetilprirazol succínico, nitrification inhibitor) and different silicon concentrations such as 0, 150, 300, 450, and 600 g ha−1. Photosynthetic leaf gas exchange, water use efficiency, pigments, CO2 emissions (ECO2), ammonium and nitrate levels in the soil were observed. The results were subjected to analysis of variance using the F test along with polynomial regression and mean comparison tests. Using urea as a source of nitrogen, there was an increase in internal CO2 concentration of the plants by 19% in relation to treatment with calcium ammonium nitrate association with DMPSA (CAN + DMPSA). Nevertheless, urea increased ECO2 emissions into the atmosphere by up to 15.3% higher compared to CAN + DMPSA application. Foliar application of Si (300 g ha−1) reduced plant transpiration rate (21%), irrespective the source of N-fertilizer utilized. Thus, it is concluded that the use of calcium ammonium nitrate associated with a nitrification inhibitor is an interesting strategy for reducing CO2 emissions, as well as Si is capable of reducing the plant’s transpiration rates, making it efficient in the use of water.

Morphophysiology of Punica Granatum L. under microalgae biomass stimulation

The use of microalgae has been proeminent in agricultural scenario, because it is an alternative product considered extremelly productive, which contains essential elements for plants. Thus, this study aimed to evaluate the morphophysiology of Punica granatum L. seedlings treated with Spirulina platensis and Scenedesmus sp. nanoparticles in controlled environment. The research was carried out at the of Federal University of Campina Grande, Pombal-PB, using a completely randomized design with five replications. The factorial scheme (2 x 4) was adopted, represented by two types of microalgae (Spirulina platensis; Scenedesmus sp.) and four doses of application (0, 5, 10 and 15%). Growth evaluations happened at 135 days after planting, verifying the number of leaves and branches and shoot length. The physiological parameters evaluated were gas exchanges, chlorophyll ‘a’ fluorescence, electron transport rate, stationary fluorescence, maximum fluorescence yield after light adaptation and quantum efficiency of PSII. Shoot length and number of branches had rises at doses of 6 and 15%. Number of leaves was induced in seedlings at dose of 8% with Spirulina platensis. Stomatal conductance and internal CO2 concentration increased in seedlings sprayed with Spirulina platensis. extract of Scenedesmus sp. improved the stationary fluorescence and quantum efficiency of PSII in pomegranate seedlings.

Change in the Physiological Aspects of Soybean Caused by Infestation by Bemisia tabaci MEAM1

Whiteflies cause significant crop losses through direct sap feeding, inducing plant physiological disorders and promoting the growth of sooty mold. Moreover, whiteflies can indirectly harm plants by transmitting plant viruses, particularly begomoviruses and criniviruses, resulting in severe viral disease epidemics. This study aimed to evaluate the physiological characteristics of susceptible and resistant soybean cultivars to B. tabaci. The experiments were conducted in a greenhouse. Eleven soybean cultivars were selected and infested with 100 adults of B. tabaci at the V3 stage. The evaluation of photosynthetic parameters, such as photosynthetic rate, leaf transpiration, stomatal conductance, and internal CO2 concentration, revealed that B. tabaci infestation influenced gas exchange in soybean plants. The photosynthetic rate was higher in cultivars AS3810 and M8349 during the V6 stage. Infestations caused alterations in photosynthetic parameters, suggesting increased energy demand to maintain photosynthetic activity. However, the response to infestation varied among the different cultivars, indicating varying levels of resistance and tolerance to the whitefly’s damage. Furthermore, the infestation had a more notable impact during the vegetative phenological stage. In summary, infestation by B. tabaci has a discernible impact on the physiology of soybean plants, resulting in alterations in gas exchange parameters and water use efficiency. The reaction to infestation exhibited variations among different soybean cultivars, indicating potential differences in resistance to the pest. This study underscores the significance of assessing the physiological consequences of whitefly infestations on soybean crops.

Effect of carboxymethyl cellulose and gibberellic acid-enriched biochar on osmotic stress tolerance in cotton

The deleterious impact of osmotic stress, induced by water deficit in arid and semi-arid regions, poses a formidable challenge to cotton production. To protect cotton farming in dry areas, it’s crucial to create strong plans to increase soil water and reduce stress on plants. The carboxymethyl cellulose (CMC), gibberellic acid (GA3) and biochar (BC) are individually found effective in mitigating osmotic stress. However, combine effect of CMC and GA3 with biochar on drought mitigation is still not studied in depth. The present study was carried out using a combination of GA3 and CMC with BC as amendments on cotton plants subjected to osmotic stress levels of 70 (70 OS) and 40 (40 OS). There were five treatment groups, namely: control (0% CMC-BC and 0% GA3-BC), 0.4%CMC-BC, 0.4%GA3-BC, 0.8%CMC-BC, and 0.8%GA3-BC. Each treatment was replicated five times with a completely randomized design (CRD). The results revealed that 0.8 GA3-BC led to increase in cotton shoot fresh weight (99.95%), shoot dry weight (95.70%), root fresh weight (73.13%), and root dry weight (95.74%) compared to the control group under osmotic stress. There was a significant enhancement in cotton chlorophyll a (23.77%), chlorophyll b (70.44%), and total chlorophyll (35.44%), the photosynthetic rate (90.77%), transpiration rate (174.44%), and internal CO2 concentration (57.99%) compared to the control group under the 40 OS stress. Thus 0.8GA3-BC can be potential amendment for reducing osmotic stress in cotton cultivation, enhancing agricultural resilience and productivity.

Effect of salinity on the toxicokinetics, oxidative stress, and metallothionein gene expression in Meretrix meretrix exposed to cadmium

To understand the effect of salinity on the toxicokinetics, oxidative stress, and detoxification of cadmium-exposed Meretrix meretrix, M. meretrix were acclimatized to different salinities (8, 14, 20, 26, and 32 ppt) for 14 d, exposed to 10 μg/L Cd for 7 d, followed by a 28-day depuration period. The internal Cd concentration was determined, and the activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), and glutathione-S-transferase (GST)), and the malondialdehyde (MDA) content were measured. The mRNA expression levels of antioxidant enzyme (Cu/Zn SOD, CAT) and detoxification-related genes metallothionein (MT) were analyzed. The mean concentrations of Cd in M. meretrix tissues were in the order gill > digestive gland > mantle > axe foot. The Cd uptake rate in the four tissues decreased with increasing salinity (range: 14–26 ppt). The Cd elimination half-lives were the highest at 8 ppt and 14 ppt salinity. Cadmium activated the four oxidative stress-related related enzymes in the gills. At the end of accumulation period, Cd exposure at 20 ppt salinity significantly increased the expression of Cu/Zn SOD. CAT expression was significantly inhibited at 20 ppt salinity, but was induced at 32 ppt. MT mRNA expression was only induced under Cd at 20 ppt salinity. At the end of depuration period, Cu/Zn SOD expression was inhibited at salinities of 8, 14, and 26 ppt. The results indicated that SOD, CAT, GST, MDA, Cu/Zn SOD, CAT, and MT were sensitive to cadmium in a water environment, and can be used as indicators of marine heavy metal pollution.

Combining the Use of Reflective Groundcovers and Aminoethoxyvinylglycine to Assess Effects on Skin Color, Preharvest Drop, and Quality of ‘Honeycrisp’ Apples in the Mid-Atlantic US

Apples are one of the most valuable fruits worldwide. ‘Honeycrisp’ is the top sales-producing cultivar in the US. Lack of red skin coloration and increased preharvest fruit drop significantly reduce the market value for cultivars such as ‘Honeycrisp’. The use of reflective groundcovers has been shown to enhance apple skin coloration. While the use of plant growth regulator AVG reduces fruit drop, it negatively affects skin coloration. Studies on the impacts of these practices in mid-Atlantic US-grown apples are limited. In this work, for two years, we compared differences in the light environment, fruit drop, internal ethylene concentration (IEC), physicochemical parameters, and skin coloration of ‘Honeycrisp’ apples in the lower third of the canopy. Apples were submitted to four treatment combinations of reflective groundcover (Extenday) and AVG (130 mg L−1). Assessments occurred throughout three ripening stages. Our results demonstrated that Extenday significantly promoted skin coloration (>75% blush) via the increased reflectance of photosynthetic photon flux density and UV radiation, and increased IEC, while also advancing fruit maturity, i.e., overripening. Conversely, AVG significantly minimized fruit drop and decreased EIC, delaying fruit maturity but drastically reducing red coloration (30–48% blush). The combined use of Extenday and AVG had a synergistic effect by decreasing fruit drop while enhancing fruit with >50% blush, without promoting overripening. Combining Extenday and AVG can boost the market value for ‘Honeycrisp’ apples in the mid-Atlantic US.

Ameliorating heat stressed conditions in wheat by altering its physiological and phenotypic traits associated with varying nitrogen levels

Currently, more than half of the global nations cultivating wheat crops are facing severe consequences of climate change and its associated heat stress in terms of quantitative and qualitative yield losses. Plants exposed to heat stress need a balanced and adequate amount of mineral nutrients to counter its ill effects. Therefore, the present study was designed to investigate the potential effects of heat stress applied during the vegetative growth period (Zadoks growth scale: ZGS 5-60) on physiological and phenotypic traits of wheat (Triticum aestivum) crop subjected to variable rates of nitrogen (N). In this experiment, wheat plants of cv. ‘Punjab-2011’ were exposed to two levels of temperature i.e. heat stress (HS) and control or non-heat stress (NHS), and three N rates (N50 = 50 kg ha-1, N100= 100 kg ha-1 and N150 = 150 kg ha-1). The experiment was executed under controlled conditions in a completely randomized design (CRD) with six replications. One set of eighteen pots containing wheat seedlings was placed in a compartment of the greenhouse under heat-stressed conditions, while another set was placed in another compartment under non-heated conditions. The greenhouse compartments were equipped with a heating and cooling system to maintain desired ecological conditions. Pots in heated chamber were kept for 60 days from emergence (ZGS = 5-60), and then shifted to non-heated chamber till harvesting. The temperature in heat stress treatment was almost 2 ± 0.47 °C higher than in non-heated treatment. The results indicated that HS significantly reduced the photosynthetic rate by 42.52%, leaf photosynthetic efficiency by 56.82%, chlorophyll scores by 20.11%, relative water contents (RWC) by 12.81%, tillers by 48.21%, grain weight by 21.47% and grain yield by 68.20% relative to NHS conditions. These reductions were more prominent in plants subjected to a limited N dose rate (50 kg N ha-1). Furthermore, the results also revealed higher transpiration rate, stomatal conductance, and membrane ruptures under HS with N50 treatment. However, N150 treatment compensated for the detrimental effects of HS on wheat plants by improving the photosynthetic rate and efficiencies, higher RWC, more stability of membrane and pigments, more tillers, and higher grain weight, and grain yield of wheat. Additionally, grain yield was negatively correlated with transpiration rate, stomatal conductance, internal CO2 concentration, and membrane leakage. In conclusion, a high dose rate of N under high temperatures during vegetative growth could alleviate the magnitude of penalties to grain yield and enhance the potential of wheat crops to withstand heat-induced detrimental effects.

Predicting forward osmosis performance with synthesized polyamide-based membrane: An integrated machine learning (MATLAB and ANN) and economic analysis framework

Forward Osmosis (FO) has emerged as a highly promising membrane-based water treatment process owing to its intrinsic advantages, such as low energy requirements and the potential for high water recovery. The lab-prepared highly efficient thin film composite (TFC) FO membranes that were used in this research work. The resultant polyamide-based FO membrane showed exceptional performance, notably achieving a high-water flux of 60.94 ± 3.5 L/m2.h and a constrained solute flux of 1.52 ± 0.08 g/m2.h. Machine learning methodologies are strategically employed in this study to construct predictive models for FO membrane performance. Notably, the accuracy of the van't Hoff equation's linear assumption is significantly enhanced by introducing an osmotic pressure calculation based on water activity, considering the nuanced effects of external and internal concentration polarization. The research employs MATLAB software alongside an artificial neural network (ANN) to develop predictive models. MATLAB facilitates the creation of a comprehensive theoretical model, offering insights into forecasting water flux through FO membranes by systematically analyzing diverse membrane parameters and their impact on performance. Concurrently, the ANN model was employed to predict the permeate flux for the laboratory-scale FO membrane system, utilizing the input parameters within the network's training range (R2 > 0.91). An economic assessment is also conducted to estimate the projected membrane cost, a pivotal determinant of system viability. Collectively, these investigations yield valuable insights into the intricacies of FO membrane design and optimization, elucidating their performance dynamics in water treatment and allied applications. This research significantly contributes to the ongoing quest to develop more efficient and precise membrane processes.

Evaluation of chickpea genotypes in Cerrado conditions in the South of the state of Tocantins

The chickpeas (Cicer arietinum L.) has potential for cultivation in the Brazilian cerrado region, its sowing supplies both the domestic market and exports, bringing benefits to the economy. In this context, the objective of this study was to evaluate morphophysiological and yield parameters in six genotypes of chickpeas with different genetic basis, which make it possible to select materials suitable for commercial cultivation under the conditions of the cerrado in the south of the state of Tocantins. Six treatments were used to carry out the experiment, each one characterized by one of the following: BRS Cícero; BRS Aleppo; BRS Khalifa; BRS Cristalino; Jamu 96 and BRS Toro. To define the best genotypes, morphophysiological characteristics of the crop were evaluated, namely: grain yield, weight of a thousand grains, plant height, number of days until flowering, number of days until maturation, chlorophyll a and b index, internal concentration of CO2, photosynthesis, stomatal conductance and transpiration. The cultivation of chickpeas in the cerrado is viable for the region. The Jamu 96 genotype stands out among the others, in the main morphophysiological characteristics, being the one that obtained the highest production averages. The genotypes BRS Cícero, BRS Aleppo and BRS Khalifa showed potential for improvement in production, due to their thousand-grain weight being similar to Jamu 96, making evident the need for genetic improvement in order to obtain genotypes more adapted to the soil and climate conditions of southern Brazil. Tocantins, making them more adapted to the region and thus increasing the production potential.