Highest Treatment Level Research Articles

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.

Anthelmintic effects of Podang mango (Mangifera indica) fruit peel waste extract through in vivo application on Indonesian Etawa goat production and health.

The continuous use of anthelmintic drugs has led to global issues of resistance. One breakthrough to address this problem is the utilization of bio-anthelmintics derived from active compounds in agro-industrial waste. This in vivo study investigated the effectiveness of Podang mango (Mangifera indica L.) fruit peel waste extract for anthelmintic purposes, using concentrations up to 5%. This study included 28 Etawa crossbred goats aged 17 months. Goats were randomly assigned to four groups: A negative control, an aqueous fruit peel extract (AFPE) group at 2.5%, another AFPE group at 5%, and a positive control receiving ivermectin. Goats chosen had egg per gram (EPG) counts surpassing 1000 before exposure to Haemonchus contortus. For 7 days within a 9-week study, AFPE from Podang mangoes was given. On the 7th day, the positive control group was administered ivermectin. AFPE dosage relied on the average abomasum fluid per kilogram of animal weight. The feeding regimen consisted of concentrate and Pennisetum purpureum cv. Mott is customized for the nutritional needs of livestock. Data on feed consumption, digestibility, average daily gain, percentage reduction in fecal egg count, body condition score, and clinical parameters were collected throughout the study. At higher treatment levels (AFPE), there was a greater reduction in both EPG and fecal egg counts. The expected and normal ranges were maintained for consumption and digestibility. While body weight increased, FAMACHA parameters showed a decrease. Compared to the negative control group, substantial disparities (p < 0.05) existed for hemoglobin, red blood cells, and hematocrit in both the positive control and the treatment groups. Blood urea nitrogen and creatinine, indicative of liver and kidney health, were within normal ranges. At a concentration of up to 5%, Podang mango waste extract (AFPE) can function as a substitute for traditional helminth medicines or bio-anthelmintics in goats, enhancing their production.

Polyvinylamine as a wet-end additive: Effects of pH and anionic contamination

The effects of polyvinylamine (PVAm) on papermaking process attributes and handsheet quality were evaluated for a recycled copy paper furnish in a near neutral-to-alkaline pH range. The degree of protonation of primary amine groups, such as those in PVAm, is known to decrease with increasing pH. Streaming potential tests surprisingly showed that a high treatment level of PVAm on the copy paper furnish was able to maintain a net positive zeta potential up to pH of about 11, whereas charge demand titrations indicated that PVAm maintained its positive charge character up to about pH 10. Favorable dewatering was observed when the furnish had been pretreated with 1% polyacrylate dispersant prior to treatment with PVAm at the 0.5% level, and the mass of filtrate increased slightly with increasing pH. First-pass retention tests showed poor retention efficiency in systems where the furnish had been treated with the dispersant, then PVAm, in an unfavorable pH range of about 9 to 9.5. Higher retention was achieved both at pH 8.2 and at pH 10 or higher. Handsheets showed superior breaking length results in the systems where the stock had been pretreated with the dispersant, though strength decreased strongly with increasing pH. Differences in filler content, as indicated by ash analysis, were not large enough to account for the observed strength differences. Formation uniformity was substantially increased by the pretreatment with dispersant, even in the presence of PVAm and throughout the studied pH range.

Clinical profile of severe hypercholesterolemia in 156,000 adults in primary care

ObjectiveTo examine the frequency of severe hypercholesterolemia (HS) and its clinical profile, and the phenotype of familial hypercholesterolemia (FH), in the primary-care setting in a large health area of ​​the Community of Madrid (CAM). Material and methodsMulticenter study of subjects with a health card assigned to 69 health centers (Northwest/CAM area). HS was defined as cholesterol ≥ 300 mg/dL or LDL-cholesterol ≥ 220 mg/dL in any analysis performed (1-1-2018 to 12-30-2021); and FH phenotype as c-LDL ≥ 240 mg/dL (≥160 mg/dL if lipid-lowering treatment) with triglycerides < 200 mg/dL and TSH < 5 uIU/ml. Results156,082 adults ≥ 18 years with an available lipid profile were analyzed. 6187 subjects had HS (3.96% of the laboratory tests studied, 95%CI 3.87%–4.06%). The mean evolution time of the diagnosis of hyperlipidemia in the computerized clinical record was 10.8 years; 36.5% had hypertension; 9.5% diabetes and 62.9% overweight/obesity. 83.7% were taking lipid-lowering drugs (65,7% low/moderate and 28.6% high/very high intensity). 6.1% had cardiovascular disease (94.2% treated with lipid-lowering agents), with LDL-cholesterol <55, <70 and <100 mg/dl of 1.8%, 5.8% and 20.2%, respectively. (vs 1%, 2.3% and 11.2% if no cardiovascular disease). 1600 subjects had FH phenotype (1.03%, 0.98%–1.08%). ConclusionsFour out of 100 patients analyzed in primary care have HS, with high treatment level, but insufficient intensity, and poor achievement of treatment goals. One in 100 have the FH phenotype. The identification of both dyslipidemias by computerized records would allow their more precise and early detection and establish cardiovascular preventive strategies.

Perfil clínico de la hipercolesterolemia severa en 156.000 adultos en atención primaria

ObjectiveTo examine the frequency of severe hypercholesterolemia (HS) and its clinical profile, and the phenotype of familial hypercholesterolemia (FH), in the primary-care setting in a large health area of the Community of Madrid (CAM). Material and methodsMulticenter study of subjects with a health card assigned to 69 health centers (Northwest/CAM area). HS was defined as cholesterol ≥300mg/dL or LDL-cholesterol ≥220mg/dL in any analysis performed (1-1-2018 to 12-30-2021); and FH phenotype as c-LDL ≥240mg/dL (≥160mg/dL if lipid-lowering treatment) with triglycerides <200mg/dL and TSH <5μIU/mL. Results156,082 adults ≥18years with an available lipid profile were analyzed. 6187 subjects had HS (3.96% of the laboratory tests studied, 95%CI: 3.87-4.06%). The mean evolution time of the diagnosis of hyperlipidemia in the computerized clinical record was 10.8years, 36.5% had hypertension, 9.5% diabetes and 62.9% overweight/obesity. 83.7% were taking lipid-lowering drugs (65.7% low/moderate and 28.6% high/very high intensity). 6.1% had cardiovascular disease (94.2% treated with lipid-lowering agents), with LDL-cholesterol <55, <70 and <100mg/dL of 1.8%, 5.8% and 20.2%, respectively (vs. 1%, 2.3% and 11.2% if no cardiovascular disease). 1600 subjects had FH phenotype (95%CI: 1.03%, 0.98-1.08%). ConclusionsFour out of 100 patients analyzed in primary care have HS, with high treatment level, but insufficient intensity, and poor achievement of treatment goals. One in 100 have the FH phenotype. The identification of both dyslipidemias by computerized records would allow their more precise and early detection and establish cardiovascular preventive strategies.

Mechanistic insights into hormesis induced by erythromycin in the marine alga Thalassiosira weissflogii

Erythromycin (ERY) is a typical macrolide antibiotic with large production and extensive use on a global scale. Detection of ERY in both freshwaters and coaster seawaters, as well as relatively high ecotoxicity of ERY have been documented. Notably, hormesis has been reported on several freshwater algae under ERY stress, where growth was promoted at relatively lower exposures but inhibited at higher treatment levels. On the contrary, there is limited information of ERY toxicity in marine algae, hampering the risk assessment on ERY in the coaster waters. The presence of hormesis may challenge the current concept of dose-response adopted in chemical risk assessment. Whether and how exposure to ERY can induce dose-dependent toxicity in marine algae remain virtually unknown, especially at environmentally relevant concentrations. The present study used a model marine diatom Thalassiosira weissflogii (T. weissflogii) to reveal its toxicological responses to ERY at different biological levels and decipher the underlying mechanisms. Assessment of multiple apical endpoints shows an evident growth promotion following ERY exposure at an environmentally relevant concentration (1 µg/L), associated with increased contents reactive oxygen species (ROS) and chlorophyll-a (Chl-a), activated signaling pathways related to ribosome biosynthesis and translation, and production of total soluble protein. By contrast, growth inhibition in the 750 and 2500 µg/L treatments was attributed to reduced viability, increased ROS formation, reduced content of total soluble protein, inhibited photosynthesis, and perturbed signaling pathways involved in xenobiotic metabolism, ribosome, metabolism of amino acid, and nitrogen metabolism. Measurements of multiple apical endpoints coupled with de novo transcriptomics analysis applied in the present study, a systems biology approach, can generate detailed mechanistic information of chemical toxicity including dose-response and species sensitivity difference used in environmental risk assessment.

Prediction of long-term remission in patients following discontinuation of anti-TNF therapy in ulcerative colitis: a 10 year follow up study

BackgroundThe long-term outcomes of Ulcerative colitis (UC) after discontinuation of biological therapy are largely unknown. There is also a lack of accurate and validated markers that can predict outcome after withdrawal accurately. The aims of this study were to describe the long-term outcomes in UC patients following cessation of anti-TNF therapy and explore potential biomarkers as an approach towards precision medicine.MethodsSeventy-five patients with moderate to severe UC treated to remission with anti-tumor necrosis factor (TNF) were included in the study. This is a follow-up of previously reported UC outcomes. The patients were categorized as either “Remission” or “Relapse”. The “Relapse” group was divided into subgroups determined by the highest treatment level needed to obtain remission the last 3 years of observation: non-biological therapy, biological therapy or colectomy. Remission were divided in long term remission (LTR), those using immunomodulating drugs (LTR + imids) and those using only 5-amino-salicylate (5-ASA) treatment (LTR) for the past 3 years. Analyses of mucosal gene expression by real-time PCR were performed.ResultsThe median (IQR) observation time of all patients included was 121 (111–137) months. Of the 75 patients, 46 (61%) did not receive biological therapy, including 23 (31%) in LTR ± imids. Of these 23 patients, 16 (21%) were defined as LTR with a median observation time of (IQR) 95 (77–113) months. In total 14 patients (19%) underwent colectomy during the 10 years after first remission. Mucosal TNF copies/µg mRNA < 10 000 at anti-TNF discontinuation predicted long-term remission, biological free remission and lower risk of colectomy with a HR 0.36 (0.14–0.92) for long-term remission, HR 0.17 (0.04–0.78) for biological free remission and HR 0.12 (0.01–0.91) for colectomy. IL1RL1 was normalized in LTR phenotype and higher in relapsing UC.ConclusionIn this 10-year follow-up of UC of patients with moderate to severe disease, 61% of patients experience an altered phenotype to a milder disease course without need of biological therapy. Twenty-one percent of the patients were LTR without any medication except of 5-ASA. Mucosal TNF gene expression and IL1RL1- transcripts may be of clinical utility for long term prognosis in development of precision medicine in UC.

Identifying Behavioral Response Profiles of Two Common Larval Fish Models to a Salinity Gradient.

Salinization of aquatic systems is an emerging global issue projected to increase in magnitude, frequency, and duration with climate change and landscape modifications. To consider influences of salinity on locomotor activity of common fish models, we examined behavioral response profiles of two species, zebrafish (Danio rerio) and fathead minnow (Pimephales promelas), across a gradient of sodium chloride. Following each experiment, behavior was recorded with automated tracking software and then behavioral response variables, including locomotor (e.g., distance traveled, number of movements, duration of movements) and photolocomotor changes, were examined at several speed thresholds (bursting, cruising, freezing) to identify potential salinity responses. Zebrafish responses were significantly (p < 0.05) reduced at the highest treatment level (5.78g/L) for multiple behavioral endpoints during both dark and light phases; however, fathead minnow responses were more variable and not consistently concentration dependent. Future efforts are needed to understand behavioral response profiles in combination with anthropogenic contaminants and natural toxins across the freshwater to marine continuum, considering salinization of inland waters, sea level rise, and transport of anthropogenic contaminants and algal toxins from inland waters to coastal systems.

Emerging Midges Transport Pesticides from Aquatic to Terrestrial Ecosystems: Importance of Compound- and Organism-Specific Parameters.

Emerging aquatic insects have the potential to retain aquatic contaminants after metamorphosis, potentially transporting them into adjacent terrestrial food webs. It is unknown whether this transfer is also relevant for current-use pesticides. We exposed larvae of the nonbiting midge, Chironomus riparius, to a sublethal pulse of a mixture of nine moderately polar fungicides and herbicides (logKow 2.5-4.7) at three field relevant treatment levels (1.2-2.5, 17.5-35.0, or 50.0-100.0 μg/L). We then assessed the pesticide bioaccumulation and bioamplification over the full aquatic-terrestrial life cycle of both sexes including the egg laying of adult females. By applying sensitive LC-MS/MS analysis to small sample volumes (∼5 mg, dry weight), we detected all pesticides in larvae from all treatment levels (2.8-1019 ng/g), five of the pesticides in the adults from the lowest treatment level and eight in the higher treatment levels (1.5-3615 ng/g). Retention of the pesticides through metamorphosis was not predictable based solely on pesticide lipophilicity. Sex-specific differences in adult insect pesticide concentrations were significant for five of the pesticides, with greater concentrations in females for four of them. Over the duration of the adults' lifespan, pesticide concentrations generally decreased in females while persisting in males. Our results suggest that a low to moderate daily dietary exposure to these pesticides may be possible for tree swallow nestlings and insectivorous bats.

Drug and pesticide usage for sea lice treatment in salmon aquaculture sites in a Canadian province from 2016 to 2019

We used 4 years of publicly available data (2016–2019) on chemical usage at salmon sites with information on production, stocking, locations and environmental conditions to explore patterns of anti-sea lice treatments in a Canadian province. Results show that sequential chemical treatments are prevalent, emamectin benzoate (EMB) with azamethiphos being the most used combination with a decrease in ivermectin usage. Relatively high rates of usage of EMB per fish biomass may point to potential lice resistance patterns with information needed on mechanisms and local populations. Lower or no chemical usage at some sites indicate less sea lice infestations likely influenced by localized site conditions (coves), and a lessened need for medication due to the usage of cleaner fish and possibly other non-chemical methods (not documented in this report). The year/climate influenced chemical input only in sites with higher treatment levels likely due to effects on sea lice growth and reproduction. Observed differences between years are warmer surface temperature in the fall, a higher freshwater input in spring, and stronger wind conditions for 2017 and 2018 with more medication usage for these two years. The lack of significant effect of site distances calculated in zones of influence based on 24 h potential connectivity patterns highlight the need to refine the resolution of hydrodynamic processes.

Manganese Accumulation and Tissue-level Distribution in the Australian Hyperaccumulator Gossia Bidwillii (Myrtaceae)

The manganese (Mn) hyperaccumulator Gossia bidwillii is a tree species native to subtropical eastern Australia where it occurs on Mn-rich soils. Here, we conducted the first Mn accumulation and tissue-level distribution study on wild and experimentally grown G. bidwillii. Gossia bidwillii plants were subjected to different levels of Mn (250 µg g−1, 500 µg g−1, 1000 µg g−1) soil dosing treatments, whereas the wild G. bidwillii was sampled from growing on highly Mn-enriched natural soils. We used laboratory-based micro-X-ray Fluorescence (µXRF) elemental mapping to elucidate in situ distribution patterns of Mn and other elements in hydrated wild and Mn-dosed G. bidwillii leaves. The data from wild G. bidwillii revealed that it can be strongly Mn-hyperaccumulating with foliar Mn concentrations of 39 000 µg g−1 and 24 000 µg g−1 in old and young leaves, respectively. In the Mn dosing trial, G. bidwillii accumulated 24 400 µg g−1 in old leaves and 17 100 µg g−1 in young leaves in the highest treatment level. The laboratory based µXRF data revealed that Mn is uniformly enriched throughout the laminae and petioles of both young and old leaves in wild G. bidwillii; while in Mn-dosed G. bidwillii, the foliar Mn distribution was primarily concentrated at the leaf-tip and lamina. The approach employed by combining data from the field and controlled experiments was especially meaningful for investigating Mn accumulation in this species and gaining added insight into the phenomenon of Mn hyperaccumulation.

P207 Clinical outcome of patients with Ulcerative colitis after anti-TNF discontinuation -\t10 years follow up

Abstract Background Biological therapy for ulcerative colitis (UC) such as anti-TNF have shown high efficacy in achieving remission. There is a lack of information about the long-term outcomes after biologic withdrawal and validated clinical, immunologic, genetic or laboratory markers that can predict outcome after withdrawal accurately. The aims of this study were to describe the long-term outcomes after anti-TNF withdrawal and discover potential biomarkers to predict long-term remission as an approach to towards personalized medicine. Methods 75 patients with moderate to severe UC treated to remission with anti-TNF were included in the study. These patients were categorized as either “Long term remission” (LTR) or “Relapse”. The “Relapse” group were divided in subgroups by the highest treatment level needed to obtain remission the last 3 years of observation: non-biological therapy, biological therapy or colectomy. LTR were divided in LTR + immunomodulating (imids) drugs and a new clinical phenotype “Near the Cure of disease” (NCD), defined as &amp;gt; 3 years in remission with no medication or 5ASA only. Results The median (IQR) observation time of all patients included were 121(111–137) months. Of the 75 patients 46 (61%) did not receive biological therapy including 23 (31%) in LTR + imids. Of the 23 patients 16 were defined as NCD with an observation time of median (IQR) 95(77–113) months. Fourteen patients underwent colectomy and 15 patients received biological therapy the last 3 years of the follow-up. Mucosal TNF copies/µg mRNA &amp;lt; 10 000 at anti-TNF discontinuation predicted long-term remission, biological free remission and lower risk of colectomy with a HR 0.36 (0.14–0.92) for long term remission, HR 0.17 (0.04–0.78) for biological free remission and HR 0.12 (0.01–0.91) for coelctomy. Conclusion This 10-year anti-TNF discontinuation follow up study of UC shows that 61% of patients experience an altered phenotype to a milder disease course without need of biological therapy. Normalized mucosal TNF transcript predict this mild disease course and lower risk of colectomy. Of special interest is that 21% of the patients defined as “Near the cure of disease” were in long-term remission without any medication or receiving 5ASA only.

Biogenic copper nanoparticles produced by using the Klebsiella pneumoniae strain NST2 curtailed salt stress effects in maize by modulating the cellular oxidative repair mechanisms

The negative effects of salinity on plant growth and physiology are well-established, which is one of the major threats to food security in semi-arid and arid regions of the world. The current research focuses on biosynthesis of copper nanoparticles (CuNPs) from a bacterial strain NST2, which was genetically identified as Klebsiella pneumoniae based on taxonomic identity of 16S rRNA gene. The strain was selected for bioprospecting of CuNPs owing to its Cu tolerance potential. The biologically-synthesized CuNPs were confirmed in culture by using ultraviolet visible spectroscopy. The material characteristics of green CuNPs were further investigated by using Fourier transform infrared spectroscopy, X-ray diffractometer, scanning electron microscopy and transmission electron microscopy, where crystallite size was ranged from 22.44 nm to 44.26 nm and particles were stabilized by various functional groups, such as carbonyl and amine groups. When 100 mg kg−1 of green CuNPs were mixed in saline soil in a pot experiment, the maize plants showed increased root and shoot length (43.52% and 44.06%, respectively), fresh weight (46.05% and 51.82%, respectively) and dry weight (47.69% and 30.63%, respectively) in comparison to control maize plants without CuNPs application. Moreover, green CuNPs at their highest treatment level (100 mg kg−1 of soil) counteracted the lipid peroxidation and oxidative damage in maize plants by promoting the activities of antioxidants and demoting the cellular levels of reactive oxygen species and ionic contents of Na+ and Cl-. Conclusively, biogenic CuNPs is an emerging and promising technique, which could replace traditional methods of salinity management in agricultural soils.

Effects of diclofenac on sentinel species and aquatic communities in semi-natural conditions

Due to the potential hazard of diclofenac on aquatic organisms and the lack of higher-tier ecotoxicological studies, a long-term freshwater mesocosm experiment was set up to study the effects of this substance on primary producers and consumers at environmentally realistic nominal concentrations 0.1, 1 and 10 µg/L (average effective concentrations 0.041, 0.44 and 3.82 µg/L). During the six-month exposure period, the biovolume of two macrophyte species (Nasturtium officinale and Callitriche platycarpa) significantly decreased at the highest treatment level. Subsequently, a decrease in dissolved oxygen levels was observed. High mortality rates, effects on immunity, and high genotoxicity were found for encaged zebra mussels (Dreissena polymorpha) in all treatments. In the highest treatment level, one month after the beginning of the exposure, mortality of adult fish (Gasterosteus aculeatus) caused effects on the final population structure. Total abundance of fish and the percentage of juveniles decreased whereas the percentage of adults increased. This led to an overall shift in the length frequency distribution of the F1 generation compared to the control. Consequently, indirect effects on the community structure of zooplankton and macroinvertebrates were observed in the highest treatment level. The No Observed Effect Concentration (NOEC) value at the individual level was < 0.1 µg/L and 1 µg/L at the population and community levels. Our study showed that in more natural conditions, diclofenac could cause more severe effects compared to those observed in laboratory conditions. The use of our results for regulatory matters is also discussed.

Functional and Microstructural Characterisation of Bambara Groundnut (Vigna Subterranea) Starch as Affected by Varying Degrees of Succinylation

Bambara groundnut (Vigna subterranea) is an under-exploited pulse rich in starch. Scientific data about the impact of varying degrees of succinylation on its starch content are sparse. Amidst the rising demand for such modified starch variants, bridging this information gap is necessary. Isolated starch from Bambara groundnut seeds was succinylated (2-14g succinic anhydride /100g starch extracted) and thereafter the degree of succinylation was evaluated. Physicochemical, functional, and microstructural characteristics of native and succinylated variants of the Bambara starch (SBS) were investigated using established procedures. Amylose content increased marginally (av.17%) among some samples. Water and oil absorption capacities peaked at 2.498 and 0.7185g /g of starch respectively. Pasting viscosities (5682-7025.5cP) increased irrespective of the order of substitution. X-ray diffract grams indicated an increase in crystallinity (A-type) with a strong peak at approximately 23o (2ϴ). This was however lost at higher treatment levels. FTIR spectra of the starches reflected a typical absorption band of a starch backbone. Scanning electron micrographs of succinylated starches were generally oval, exhibiting surface cracks sizes (13.55-44.25µm). Succinylated Bambara groundnut starches at low treatment levels (2-4%) may prove valuable in soups and gravies requiring a high viscosity, stability, and clarity. At higher treatment levels, non-food applications may just be the right outlet.

Fluoride hyperaccumulation in

Members of the Australian endemic plant genus Gastrolobium (Fabaceae) naturally accumulate fluoride (F) in the form of fluoroacetate when growing on soils with very low F status. However, it is unknown how Gastrolobium species respond to higher soil F concentrations, and what the interactions are between cations (Na+, Mg2+, K+, Ca2+) and anions (Cl−, F−, SO42−) in their leaves. In this study, we exposed G. bilobum, G. parviflorum and G. parvifolium to soils with different levels of soluble F− (as sodium fluoride solution applied to soil at 0, 1, 10, 50, 100 μg F g−1). The plants were grown for a period of 12 months before being harvested and acid- and water-extractable F in shoots analysed using ion chromatography. Gastrolobium leaves accumulated extremely high F with highest concentrations in young leaves in the highest treatment level. In G. parviflorum, the mean concentration of F in young leaves was &gt;8000 μg g−1 for both methods of extraction, whereas G. parvifolium had 6940 and 3630 μg g−1 in young leaves for the water-soluble and acid extraction methods respectively. In young leaves of G. bilobum, the concentration of F was 1840 and 7970 μg g−1 for the water-soluble and acid extraction methods respectively. This study further revealed significant amounts of Cl− and SO42− in foliage of the studied species. Moreover, we found F− and SO42− to be positively correlated in young leaves of G. bilobum, but inversely related in its old leaves. These findings have shown for the first time the potential of Gastrolobium species to accumulate F in soils with high F concentrations, highlighting potential for applications in phytoremediation.

Effects of thermal modification on physical and mechanical properties of Mozambican Brachystegia spiciformis and Julbernardia globiflora wood

Mozambique’s large pool of tropical hardwoods is hampered by the prevalence of low-grade tree species along with a lack of cost-effective processing technologies to improve timber properties. Brachystegia spiciformis and Julbernadia globiflora are the most abundant tree species in terms of volume in the country, but with limited use due to their low timber quality. In this study, thermal modification at three different temperatures (215 °C; 230 °C; 245 °C) was applied for 2 h to the timber of both species, followed by measurement of a set of physical and mechanical wood properties. The results show that the originally light-coloured sapwood of both tree species darkened gradually as the intensity of thermal modification increased. Additionally, from untreated samples to the highest thermal treatment level, timber of B. spiciformis incurred a maximum mass loss of 27%, while oven-dry density was reduced from 0.65 to 0.56 g/cm3 and equilibrium moisture content (EMC) changed from 7 to 3%. Timber of J. globiflora had a mass loss of 23% after the highest treatment level, an oven-dry density reduction of 0.81 to 0.74 g/cm3 and an EMC decrease from 8 to 3%. The changes in mechanical properties from reference samples to the highest thermal treatment level were also significant. For B. spiciformis, MOE decreased by 10.2%, MOR by 50.8%, compression strength parallel to the grain by 29.2% and Brinell hardness by 23.5%. Timber of J. globiflora followed the same trend with an MOE decrease by 6.9%, an MOR decrease by 53.2% and a decrease in compression strength parallel to the grain by 21.9%. All tested wood properties showed significant responses to thermal modification after the most intensive treatment level had been applied. Despite the degradation of mechanical properties in both species, an optimal combination of temperature and treatment time could be achieved. The recorded changes of the tested wood properties in both species could increase the range of applications; the new colour resembled that of highly sought-after tropical hardwoods.

8:8 Perfluoroalkyl phosphinic acid affects neurobehavioral development, thyroid disruption, and DNA methylation in developing zebrafish

Recent studies have reported potential neurotoxicity and epigenetic alteration associated with exposure to several per- and polyfluoroalkyl substances (PFASs). However, such information is limited to a few compounds (e.g., perfluorooctane sulfonate), primarily based on rodent experiments, and the underlying toxicological mechanism(s) for many PFAS in the environment remain poorly understood. In the present study, we investigated 8:8 perfluoroalkyl phosphinic acid (8:8 PFPiA), an under-studied PFAS with high persistency in the environment and biota, using the zebrafish model. We exposed zebrafish embryos (<4 hpf) to various concentrations of 8:8 PFPiA (0, 0.0116, 0.112, 0.343, 1.34, 5.79 μM) for 144 h. Although there was no significant change in survival, hatchability and malformations, zebrafish locomotor speed at 120 h significantly decreased in dark photoperiod. At 144 h, several genes related to thyroid hormones that are essential for neurodevelopment, including corticotropin releasing hormone b (crhb), iodothyronine deiodinase 3a (dio3a), thyroid-stimulating hormone receptor (tshr) and nkx2 homeobox1 (nkx 2.1), were up-regulated by 8:8 PFPiA at 5.79 μM. 8:8 PFPiA also significantly down-regulated a neurodevelopmental gene, elav like neuron-specific RNA binding protein (elavl3), at 1.34 and 5.79 μM; in addition, one oxidative stress gene was slightly but significantly up-regulated. Further, global DNA methylation was significantly decreased at higher treatment levels, identifying effects of 8:8 PFPiA on epigenetic regulation. However, promoter DNA methylation of selected genes (dio3, tshr, nkx2.1) were not statistically altered, though dio3 methylation showed a decreasing trend with 8:8 PFPiA exposure. Our results specifically advance an understanding of molecular toxicology of PFPiA and more broadly present an approach to define diverse responses during animal alternative assessments of PFASs.

Effects of chronic exposure to a pharmaceutical mixture on the three-spined stickleback (gasterosteus aculeatus) population dynamics in lotic mesocosms

Pharmaceutical substances are ubiquitous in the aquatic environment and their concentration levels typically range from ng/L up to several μg/L. Furthermore, as those compounds are designed to be highly biologically active, assessing their impacts on non-target organisms is important. Here, we conducted a mesocosm experiment testing a mixture of five pharmaceuticals (diclofenac, carbamazepine, irbesartan, acetaminophen and naproxen) on fish, three-spined stickleback (Gasterosteus aculeatus). The mixture concentration levels were chosen on the basis of the contamination of the Meuse river in Belgium which had been measured previously during a monitoring campaign undertaken in 2015 and 2016. Three nominal mixture concentration levels were tested: the lowest concentration level mixture was composed by environmentally-relevant concentrations that approximate average realistic values for each pharmaceuticals (Mx1); the two other levels were 10 and 100 times these concentrations. Although no impact on stickleback prey was observed, the mixture significantly impaired the survival of female fish introduced in the mesocosms at the highest treatment level without causing other major differences on fish population structure. Impacts on condition factors of adults and juveniles were also observed at both individual and population levels. Using a modelling approach with an individual-based model coupled to a bioenergetic model (DEB-IBM), we concluded that chronic exposure to environmentally-relevant concentrations of five pharmaceuticals often detected in the rivers did not appear to strongly affect the three-spined stickleback populations. Mechanisms of population regulation may have counteracted the mixture impacts in the mesocosms.

Microwave Assisted Preparation of Self-Extinguishing Cotton Fabrics by Small Molecules Containing Phosphorous and Nitrogen

Background: New methods for preparing surface modification of flame retardant cotton fabrics were employed by applying a microwave-assisted technique with a minimum amount of co-solvent. Efforts at flame retardant cotton fabrics treated with economic and environmentally friendly flame retardant compounds based on the small molecules piperazine, PN and PNN, were done successfully. Methods and Results: The evidence of flame retardant chemical penetrations or surface modification of cotton fabrics was confirmed by Scanning Electron Microscope (SEM), and the treated cotton fabrics were evaluated by flammability tests, such as 45°angle (clothing textiles test) and limiting Oxygen Index (LOI). Thermogravimetric analysis of all treated cotton fabrics in a nitrogen atmosphere showed high thermal stability, as decomposition occurred between 276.9~291.2°C with 30.5~35.7% residue weight char yield at 600°C. Limiting Oxygen Index (LOI) and the 45° angle flammability test were used to determine the efficiency of the flame-retardant treatments on the fabrics. LOI values for control twill fabric showed ~18 vol% oxygen in nitrogen, whereas the highest treatment level had 32 vol%. High add-on treatments with flame retardants also readily passed the 45° angle flammability test. Conclusion: In the Microscale Combustion Calorimeter (MCC) tests, a decline in heat of combustion was shown through the smaller values acquired for THR, HRC and Tmax for all PN and PNN samples.