Elevated pH Levels Research Articles

Algal Density Controls the Spatial Variations in Hg Bioconcentration and Bioaccumulation at the Base of the Pelagic Food Web of Lake Taihu, China.

Algal density can significantly impact mercury (Hg) bioaccumulation and biomagnification in aquatic food webs, but the underlying mechanisms remain controversial especially in subtropical and tropical regions. We conducted a comprehensive field study on Hg bioconcentration in phytoplankton and bioaccumulation in size-fractionated zooplankton across 17 sampling sites in Lake Taihu, a large shallow lake in eastern China with large spatial differences in algal density. The higher algal density in the northern sites is highly associated with the lower THg bioconcentration factor (BCF) in phytoplankton and lower THg bioaccumulation factor (BAF) in zooplankton. The low Hg BCFs or BAFs at productive sites could not be explained by algal bloom dilution but attributed to the low Hg bioavailability, which is highly associated with the elevated pH levels at productive sites. The smaller body size of the dominant zooplankton species at higher algal density sites also contributed to their lower Hg bioaccumulation. Importantly, we provide evidence that high algal density is associated with a low proportion of methylmercury (MeHg) in total Hg (% MeHg) in phytoplankton, which is further transferred to zooplankton. Such a low THg BCF or BAF and low % MeHg in plankton at high algal density sites hamper the entry of Hg into the pelagic food webs, which are important but yet underestimated driving forces for the low Hg contents in pelagic fish that are commonly observed in anthropogenic-impacted eutrophic lakes in subtropical regions.

Low-Cost Nonreversible Electronic-Free Wireless pH Sensor for Spoilage Detection in Packaged Meat Products.

Contamination of meat with pathogenic microorganisms can cause severe illnesses and food waste, which has significant negative impacts on both general health and the economy. In many cases, the expiration date is not a good indicator of meat freshness as there is a high risk of contamination during handling throughout the supply chain. Many biomarkers, including color, odor, pH, temperature, and volatile compounds, are used to determine spoilage. Among these, pH presents a simple and effective biomarker directly linked to the overgrowth of bacteria and degradation of the meat tissue. Low-cost methods for wireless pH monitoring are crucial in detecting spoilage on a large commercial scale. Existing technologies are often limited to short-range detection, with the use of batteries and different electronic components that increases both the manufacturing complexity and cost of the final device. To address these shortcomings, we have developed a cost-effective wireless pH sensor, which uses passive resonant frequency (RF) sensing, combined with a pH-responsive polymer that can be placed within packaged meat products and provide a remote assessment of the risk of microbial spoilage throughout the supply chain. The sensor tag consists of a sensing resonator coated with a pH-sensitive material and a passivated reference resonator operating in a differential frequency configuration. Upon exposure to elevated pH levels >6.8, the coating on the sensing resonator dissolves, which in turn results in a distinct change in the resonant frequency with respect to the reference resonator. Systematic theoretical and experimental results at different pH levels demonstrated that a 20% shift in resonant frequency demarcates the point for spoilage detection. As a proof of concept, the performance of the sensor in remotely detecting the risk of food spoilage was validated in packaged poultry over 10 days. The sensor fabrication process takes advantage of recent developments in the scalable manufacturing of flexible, low-cost devices, including selective laser etching of metalized plastic films and doctor-blade coating of stimuli-responsive polymer films. Furthermore, the biocompatibility of all the materials used in the sensor was confirmed with human intestinal cells (HCT-8 cells).

The effects of high‐pressure homogenization, drying pH and propylene glycol on the emulsifying properties of pea protein powder

SummaryPea protein is a promising option for plant protein‐based emulsification, but commercial proteins have limited functional properties related to their poor physicochemical properties such as solubility. To address this issue, this research investigated the effects of high‐pressure homogenisation and extraction conditions on the solubility and emulsification properties of pea protein. Heating during extraction can denature pea protein and simulate the reduced functional properties of commercial proteins. Homogenising at 10 000 psi combined with the heating process during extraction significantly improved the solubility and emulsification properties of pea protein. Freeze drying at pH 9.0 improved the solubility of pea protein and lowered the droplet size of resultant emulsions compared to pH 7.0. Extracting the protein in propylene glycol to inhibit hydrophobic interactions slightly improved solubility but decreased the emulsification properties. The combination of homogenisation during heating and freeze drying at an elevated pH produced the optimum solubility and emulsification properties. These results suggest that high‐pressure homogenisation and drying at elevated pH levels can be effective tools to limit the functionality‐reducing effects of denaturation that occurs during the commercial extraction of pea protein. This information can be used to design better production methods for pea protein and improve its functional properties.

Study of polymethylmethacrylate/tricalcium silicate composite cement for orthopedic application

BackgroundAmong orthopedic surgery materials, poly (methyl methacrylate) (PMMA) is most commonly used for its excellent mechanical properties and rapid self-setting time. However, PMMA bone cement has been reported to cause thermal necrosis and to have poor bioactivity, which must be improved. In contrast, tricalcium silicate (TCS), the most significant component of Portland Cement and the most effective bone cement material, might not always meet the needs of the cement due to its poor mechanical properties and elevated pH levels during hydration. We hypothesize that the benefits of both PMMA and TCS can be harnessed by mixing them together in different proportions. This would represent a better solution for the issues faced when using them alone. MethodsWe, therefore, prepared a novel organic-inorganic PMMA/TCS composite bone cement mixing PMMA and different amounts of TCS and tested its effect on the biophysical properties. ResultsThe addition of 30% TCS reduced the exothermic temperature and pH variation during cement setting and hydration processes. However, the mechanical and handling properties of the bioactive PMMA/TCS composite were not affected. The in vitro study also revealed that the composite materials had higher cell viability than pure PMMA and TCS. Also, the in vivo study on animals indicated that the composite materials were more capable of forming bone, which further reinforced the biocompatibility of the proposed PMMA/TCS bone cement. ConclusionBy combining the advantages of each component, it could be possible to construct a more effective composite bone cement material. This would meet the needs of implantation material for orthopedic surgeries or a possible bone filler.

Effect of algal contact time and horizontal water velocity on the performance of Filamentous Algal Nutrient Scrubbers (FANS)

We investigated the effect of algal contact time (ACT) and horizontal water velocity (HWV) on the performance of pilot-scale Filamentous Algae Nutrient Scrubbers (FANS) treating river water during the NZ summer. The FANS floways were seeded with a mixture of four New Zealand native filamentous algal species (Oedogonium sp., Cladophora sp., Rhizoclonium sp., and Spirogyra sp.) and allowed to establish over one month. River water was pumped onto the top of each FANS at different flow rates (2, 4 or 8 L min−1) to give ACTs from 0.6 to 10.1 min depending on FANS length (6–24 m) and HWV from 0.04 to 0.16 m s−1. FANS inflow and final outflows were monitored three times a week for nitrate and DRP concentrations and FANS algal biomass was harvested weekly. Average biomass productivity was significantly higher on the FANS with shorter ACT. For example, biomass productivity of the 24 m length FANS with 2.5 min ACT were 67% higher (11.2 g DW m−2 d−1) than that with four times the ACT (10.1 min). Irrespective of the HWV the biomass productivity declined down the length of the floways (with longer ACT) and the decline was greater at lower HWV. The decreased biomass productivity at lower HWV (and/or higher ACT) was likely attributable to the daytime carbon limitation of photosynthesis (at pH > 9.5) and heat stress with elevated daytime water temperature (at >30 °C). Despite the short ACT (<10.1 min) the single pass pilot-scale FANS effectively removed both nitrate-N and DRP from the river water, with >35% removal of both NO3–N (from 0.49 to <0.32 mg N L−1) and DRP (from 0.14 to <0.09 mg P L−1). Both the nitrogen and phosphorus content of the harvested algal biomass were unaffected by both HWV and ACT and typical (N: ∼2.0%; P: 0.2–0.3%) of the literature values (N: 1.5–3.0%; P: 0.15–0.32%). Compared with constructed wetland nutrient removal (0.1 g N m−2 d−1; 0.08 g P m−2 d−1), the FANS achieved up to 2.5-fold higher nitrogen removal (0.24 N m−2 d−1) through algal nitrogen assimilation followed by subsequent algal harvest and up to 4-fold higher phosphorus removal (0.34 g P m−2 d−1) through a combination of algal phosphorus assimilation and some P-precipitation under photosynthesis-mediated elevated daytime pH levels (pH > 9.0). This research indicates that FANS have the potential to require less than half the land area of constructed wetlands for the same level of nitrogen removal and that they require only a few weeks to establish to achieve full performance. Moreover, FANS have the further benefit of resource recovery for beneficial re-use of harvested algal biomass for animal feed, fertiliser, or biofuel.

Physiological and Behavioral Responses of Age‐0 Muskellunge during Simulated Stocking in Elevated pH Water

AbstractSuccessful stocking of Muskellunge Esox masquinongy into reservoirs is hampered by a variety of stressors that can affect poststocking survival, such as elevated pH conditions common to eutrophic water bodies. We quantified Muskellunge survival, behavior, and physiological responses during a simulated stocking event where age‐0 Muskellunge were netted, held on a hauling truck for 2 h, and then released into water with either the same pH (8.4) or one of two elevated pH levels (8.6 or 9.8). Following the hauling simulation, Muskellunge exhibited an upregulation of plasma‐associated stress responses. Stocking into high‐pH water did not cause mortality, but Muskellunge stocked into pH 9.8 showed signs of stress through ion imbalances and increased surfacing behavior. Four hours after stocking there were indications of recovery with reduced indicators of physiological stress, but Muskellunge did not fully recover in that time. Our study suggests that elevated pH alone may not result in short‐term (≤4 h postrelease) poststocking mortality of age‐0 Muskellunge but does add to the cumulative stress incurred during the stocking process.

Skin microbiome alterations in seborrheic dermatitis and dandruff: A systematic review.

Seborrheic dermatitis (SD) and dandruff (DF) are common chronic inflammatory skin diseases characterized by recurrent greasy scales, sometimes with erythema and itchiness. Although the exact pathophysiology of the disease is still unclear, current theories highlight the role of microbes on the skin surface in the pathogenesis of SD. Here, we conducted a systematic review to investigate the skin microbiome alterations in patients with SD/DF. We searched Medline/PubMed, Embase and Web of Science for research studies published in English between 1January 2000 and 31 December 2020. A total of 12studies with 706 SD/DF samples and 379healthy samples were included in this study. The scalp and face were predominated by the fungi of Ascomycota and Basidiomycota and the bacteria of Actinobacteria and Firmicutes. In general, the included studies demonstrated an increased Malassezia restricta/Malassezia globosa ratio and a reduction in the Cutibaterium/Staphylococcus ratio in the setting of SD/DF. Staphylococcus was associated with epidermal barrier damage, including elevated levels of trans-epidermal water loss and pH, while Cutibacterium had a positive correlation with water content. Malassezia was also found to be related to an increased itching score and disease severity. Further studies focusing on the interactions between various microbes and the host and microbes can help us to better understand the pathogenesis of SD/DF.

Phosphorus fractions in biochar-amended soil — chemical sequential fractionation, 31P NMR, and phosphatase activity

ABSTRACT In this study, we assessed the effects of biochar application for five years on soil phosphorus (P) factions by chemical sequential P fractionation, phosphatase activity, and 31P NMR. Four treatments were included in this research: two biochar (0 and 2.63 t ha−1) levels blended with two P fertilizer levels (0 and 26 kg P ha−1), respectively. We found elevated levels of soil pH, total carbon (C), and total P in soil exposed to biochar. The inorganic (Ca8 – P, Al – P, Fe – P, and Ca10 – P) and organic (LOP and HROP) P fractions were all enhanced by biochar regardless of the application of P fertiliser. 31P NMR spectra further showed that ortho – P, monoester – P, and diester – P levels in the soil with added biochar combined with P fertiliser were 464.5 mg kg−1, 74.3 mg kg−1, and 13.9 mg kg−1, respectively, which were the highest among all treatments. Biochar application increased alkaline phosphomonoesterase activity by 24.4–32.7% and decreased phosphodiesterase activity by 10.2–11.0%. In conclusion, biochar application significantly improves soil P fractions and regulates phosphatase activity.

Complete Cu removal through Fe(II) mediated decoupling of CuEDTA complexes from simulated industrial wastewater with simultaneous precipitation

A complete removal of Cu from CuEDTA complexes by replacement/precipitation reactions using ferrous ions was realized. The effects of pH, iron dosage and reactions time on Cu removal were evaluated. The results were explained with the aid of chemical equilibrium modeling. Fe(III) ions effectively liberate Cu(II) ions from CuEDTA complexes by the replacement reaction at an acidic pH region, but the precipitation of ferric hydroxides at elevated pH levels renders a negative effect on Cu removal. In contrast, Fe(II) ions replace Cu(II) effectively at an alkaline pH region, where both replacement and precipitation of Cu can take place simultaneously. Cu removal was enhanced and was independent of the precipitation time when Fe(II) was dosed instead of Fe(III), reaching 100% removal of Cu at Cu:EDTA:Fe molar ratio of 1:1:5. The treatment efficacy of the replacement/precipitation processes for Cu removal followed by Fenton process for COD removal was compared with that of Fenton process for COD removal followed by alkaline precipitation for Cu removal. A complete Cu removal was achieved by the former, whereas only 40%–66% of Cu was removed by the latter.

Improving the alkaline stability of pepsin through rational protein design using renin, an alkaline-stable aspartic protease, as a structural and functional reference

The present study sought to identify the structural determinants of aspartic protease structural stability and activity at elevated pH. Various hypotheses have been published regarding the features responsible for the unusual alkaline structural stability of renin, however, few structure-function studies have verified these claims. Using pepsin as a model system, and renin as a template for functional and structural alkaline stability, a rational re-design of pepsin was undertaken to identify residues contributing to the alkaline instability of pepsin-like aspartic proteases in regards to both structure and function. We constructed 13 mutants based on this strategy. Among them, mutants D159 L and D60A led to an increase in activity at elevated pH levels (p ≤ 0.05) and E4V and H53F were shown to retain native-like structure at elevated pH (p ≤ 0.05). Previously suggested carboxyl groups Asp11, Asp118, and Glu13 were individually shown not to be responsible for the structural instability or lack of activity at neutral pH in pepsin. The importance of the β-barrel to structural stability was highlighted as the majority of the stabilizing residues identified, and 39% of the weakly conserved residues in the N-terminal lobe, were located in β-sheet strands of the barrel. The results of the present study indicate that alkaline stabilization of pepsin will require reduction of electrostatic repulsions and an improved understanding of the role of the hydrogen bonding network of the characteristic β-barrel.

Survivability of Alcaligenaceae and Chromatiaceae as palm oil mill effluent pollution bioindicators under fluctuations of temperature, pH and total suspended solid

Alcaligenaceae and Chromatiaceae were previously reported as the specific pollution bioindicators in the receiving river water contaminated by palm oil mill effluent (POME) final discharge. Considering the inevitable sensitivity of bacteria under environmental stresses, it is crucial to assess the survivability of both bacteria in the fluctuated environmental factors, proving their credibility as POME pollution bioindicators in the environment. In this study, the survivability of Alcaligenaceae and Chromatiaceae from facultative pond, algae (aerobic) pond and final discharge were evaluated under varying sets of temperature (25-40°C), pH (pH 7-9) and low/high total suspended solid (TSS) contents of POME collected during low/high crop seasons of oil palm, respectively. Following treatment, the viability status and compositions of the bacterial community were assessed using flow cytometry-based assay and high-throughput Illumina MiSeq, respectively, in correlation with the changes of physicochemical properties. The changes in temperature, pH and TSS indeed changed the physicochemical properties of POME. The functionality of bacterial cells was also shifted where the viable cells and high nucleic acid contents reduced at elevated levels of temperature and pH but increased at high TSS content. Interestingly, the Alcaligenaceae and Chromatiaceae continuously detected in the samples which accounted for more than 0.5% of relative abundance, with a positive correlation with biological oxygen demand (BOD5) concentration. Therefore, either Alcaligenaceae or Chromatiaceae or both could be regarded as the reliable and specific bacterial indicators to indicate the pollution in river water due to POME final discharge despite the fluctuations in temperature, pH and TSS.

Ex Vivo Electrochemical pH Mapping of the Gastrointestinal Tract in the Absence and Presence of Pharmacological Agents.

Ex vivo pH profiling of the upper gastrointestinal (GI) tract (of a mouse), using an electrochemical pH probe, in both the absence and presence of pharmacological agents aimed at altering acid/bicarbonate production, is reported. Three pH electrodes were first assessed for suitability using a GI tract biological mimic buffer solution containing 0.5% mucin. These include a traditional glass pH probe, an iridium oxide (IrOx)-coated electrode (both operated potentiometrically), and a quinone (Q) surface-integrated boron-doped diamond (BDD-Q) electrode (voltammetric). In mucin, the time scale for both IrOx and glass to provide a representative pH reading was in the ∼100's of s, most likely due to mucin adsorption, in contrast to 6 s with the BDD-Q electrode. Both the glass and IrOx pH electrodes were also compromised on robustness due to fragility and delamination (IrOx) issues; contact with the GI tissue was an experimental requirement. BDD-Q was deemed the most appropriate. Ten measurements were made along the GI tract, esophagus (1), stomach (5), and duodenum (4). Under buffer only conditions, the BDD-Q probe tracked the pH from neutral in the esophagus to acidic in the stomach and rising to more alkaline in the duodenum. In the presence of omeprazole, a proton pump inhibitor, the body regions of the stomach exhibited elevated pH levels. Under melatonin treatment (a bicarbonate agonist and acid inhibitor), both the body of the stomach and the duodenum showed elevated pH levels. This study demonstrates the versatility of the BDD-Q pH electrode for real-time ex vivo biological tissue measurements.

Influence of Elevated pH on Germination, Growth Attributes and ABA Contents of Sticky Mouse-Ear Chickweed (Cerastium glomeratum Thuill.)

Sticky mouse-ear chickweed (Cerastium glomeratum Thuill.) is a dominant annual weed of Korea. Control management of such an exotic weed is a challenging task for agronomist and researcher over the years. We evaluated the effect of elevated pH levels on the germination, growth, chlorophyll content, nutrients and hormonal regulation of sticky mouse-ear chickweed under green-house conditions. Our results showed that pH have no significant effect on seed germination except pH3, which reduced germination rate by 10%. Maximum hypocotyl and radicle growth was observed at pH5 and pH7, while hypocotyl failed to emerge at pH 3. Plant growth attributes showed that plant height, fresh biomass, number of leaves and chlorophyll content were higher at pH7 and pH9; while lowest number of leaves (24.8 ± 2.8) and chlorophyll content (313.2 ± 11.2 SPAD) were recorded for pH3. The endogenous ABA levels were significantly higher at pH3 (71.22±5.4ng/g) but lowered at pH7 and pH9 (6.6±0.8 ng/g). The weed nutrients uptake result showed higher Fe (858.47 mg/kg) and Al (835.05 mg/kg) at pH 3 and pH 5; while higher Ca content (4887.2 mg/kg) was observed at pH 5. It was concluded that use of varying pH can play a vital role in the weed management, although its possible adverse impact on endemic flora and fauna needs to be assessed.

Comparison of four oxidants activated through tetraacetylethylenediamine for developing sustainable and rapid degradation of organic dye

AbstractFour common oxidants, including hydrogen peroxide (H2O2), sodium percarbonate (SPC), sodium perborate (SPB) and sodium persulphate (SPS), were activated with tetraacetylethylenediamine (TAED) to degrade an azo dye, CI Reactive Red 195, in water, for building a novel and rapid oxidative system comprising the merits of cost‐effectiveness and high sustainability. Elevated temperature and high pH level enhanced the activation effect of TAED for accelerating dye degradation. Peracetic acids were confirmed to be the main oxidative species for dye degradation in four TAED/oxidant systems. Hydroxyl radicals and sulphate radicals were also involved in dye degradation in the TAED/SPS system, which showed a stronger oxidative capacity than the other three systems over a wide pH range. More importantly, the addition of inorganic salts or surfactants also favoured the dye degradation in TAED/oxidant systems. Although a slow mineralisation process of the dye was found when the TAED/SPC or SPS system was used, low‐toxic intermediates were detected after the degradation.

The microbiome as a biosensor: functional profiles elucidate hidden stress in hosts

BackgroundMicrobial communities are highly responsive to environmental cues, and both their structure and activity can be altered in response to changing conditions. We hypothesized that host-associated microbial communities, particularly those colonizing host surfaces, can serve as in situ sensors to reveal environmental conditions experienced by both microorganisms and the host. For a proof-of-concept, we studied a model plant-soil system and employed a non-deterministic gene-centric approach. A holistic analysis was performed using plants of two species and irrigation with water of low quality to induce host stress. Our analyses examined the genetic potential (DNA) and gene expression patterns (RNA) of plant-associated microbial communities, as well as transcriptional profiling of host plants.ResultsTranscriptional analysis of plants irrigated with treated wastewater revealed significant enrichment of general stress-associated root transcripts relative to plants irrigated with fresh water. Metagenomic analysis of root-associated microbial communities in treated wastewater-irrigated plants, however, revealed enrichment of more specific stress-associated genes relating to high levels of salt, high pH and lower levels of oxygen. Meta-analysis of these differentially abundant genes obtained from other metagenome studies, provided evidence of the link between environmental factors such as pH and oxygen and these genes. Analysis of microbial transcriptional response demonstrated that enriched gene content was actively expressed, which implies contemporary response to elevated levels of pH and salt.ConclusionsWe demonstrate here that microbial profiling can elucidate stress signals that cannot be observed even through interrogation of host transcriptome, leading to an alternate mechanism for evaluating in situ conditions experienced by host organisms.This study is a proof-of-concept for the use of microbial communities as microsensors, with great potential for interrogation of a wide range of host systems.57aYexsF8NV8L7XUrRg9nmVideo

Hydrogeological controls of arsenic and uranium dissolution into groundwater of the Pine Ridge Reservation, South Dakota

AbstractThis study integrates geochemical modeling, spatial analysis and several statistical methods including principal component analysis, multivariate regression and cluster analysis to investigate hydrogeologic controls of arsenic and uranium contamination within groundwater of the Arikaree aquifer on the Pine Ridge Reservation (PRR). Located in southwestern South Dakota, the PRR is largely rural and many people rely on domestic supply wells completed in the Arikaree aquifer as their primary drinking water source. Locally, the White River Group, which unconformably underlies the Arikaree Group, is enriched in arsenic and uranium related to volcanic ash deposits and acts as a geogenic metal source. Geochemical data from over 250 groundwater samples were obtained through collaboration with the Oglala Sioux Tribe. Cluster spatial statistics analyses delineated four regions of statistically significant variations in groundwater chemistry that represent upgradient, intermediate, and downgradient portions of the Arikaree aquifer. Groundwater evolves as it flows through the Arikaree aquifer with increasing alkalinity, sodium, and pH along flow paths. These chemical changes are likely due to dissolution of carbonate minerals and volcanic ash. Thermodynamic calculations suggest increasing supersaturation of the groundwater with respect to calcite; thus, volcanic ash dissolution may be an important secondary source of alkalinity. Elevated alkalinity and pH levels were found to be the driving factors of arsenic and uranium mobility, and downgradient sections of the aquifer in the northern portions of the PRR are most likely to be impacted by metal(loid) contamination, with 73% of the wells in this grouping failing a USEPA maximum contaminant level for arsenic, uranium, and/or gross alpha.

Characterization of Nanohydroxyapatite isolated from Seer Fish Bones and Waste Scales and its Applications in Lead Removal

Hydroxyapatite, (HA), Ca10(PO4)6(OH)2, is recognized as a biomaterial and extensively used for bone implant because of its structural and chemical similarity with mineral components of enamel and human bone. The elements of HA are largely composed of calcium and phosphorus molar ratio of 1.67 and is capable of promoting bone in-growth into prosthetic implant. Huge amounts of by-product waste generated from fish processing industry and market generated an undesirable environmental impact. In this perspective, the present study focused on the isolation and characterization of nanohydroxyapatite (nHA) from bones and waste scales of seer fish. Tissue removal process was carried out by boiling bones and scales at 100°C for 4-5 hours and further boiling with acetone and sodium hydroxide. nHA was isolated by alkaline hydrolysis treatment. The isolated nHA was characterized by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) – Energy Dispersive Spectroscopy (EDS). FT-IR spectrum disclosed the presence of functional groups of HA. SEM-EDS revealed the size shape and elemental composition of the isolated nHA. Further, the application of this isolated nHA in removal of lead was also investigated. At elevated pH levels, nHA adsorbed the lead ions effectively with reduction in lead ions greater than 95%. These results suggest that nHA isolated from bones and waste scales of seer fish can be potentially used for waste water treatment.

Invasive lianas are drivers of and passengers to altered soil nutrient availability in urban forests

Lianas (woody vines) are a leading concern in urban forest management given their ability to reduce the growth rate and survival of trees. Efforts to control invasive lianas are widespread, yet forests are often reinvaded following management. Changes in soil nutrient availability could help explain why some forests are susceptible to reinvasion. Specifically, invasive lianas could be “drivers” of altered nutrient dynamics that persist in the soil and favor their re-establishment, or they could be “passengers” of conditions created by prior site disturbances. We test these alternative models by analyzing soils across gradients of liana cover and forest disturbance in mature hardwood forests in New York City. Overall, total non-native liana cover was linked to elevated soil pH, reduced labile carbon, and altered net potential nitrification—three conditions indicative of increased soil nutrient availability. However, the effects of lianas varied substantially by species. Non-native lianas had a positive, negative, neutral, or non-linear effect on a single soil variable depending on the species. Aggregation of total non-native liana cover can therefore obscure the direction and magnitude of species-level effects. We also found positive relationships between forest disturbance, non-native liana cover, and soil pH, but we found no relationships between disturbance and net nitrification or labile carbon. These results suggest that non-native lianas are passengers to elevated levels of disturbance and soil pH but drivers of altered carbon and nitrogen dynamics. As such, management efforts aimed at reducing soil nutrient availability and removing invasive lianas may be required to limit reinvasion and promote ecosystem recovery.

In depth analysis of groundwater quality and use of Moringa oleifera leaf powder treatment to improve physico-chemical properties and drinkability of contaminated groundwater

Groundwater is the major source for domestic, and other uses in the Jaffna Peninsula, Sri Lanka. This study assessed the spatial and seasonal variation of physical and chemical parameters of water collected from domestic wells in Chunnakam and Vadamaradchi aquifers. The measured physicochemical parameters were compared with the drinking water standards established by Sri Lanka Standards Institution.Significant spatial variations in the water quality parameters were identified in both areas. Significantly elevated levels of nitrate and oil & grease were identified in Chunnakam, whereas significantly elevated levels of DO and pH were recorded in Vadamaradchi. Nitrate concentration of the wells ranged between 0.021–40.1 mg/L. Oil & grease of these wells ranged from 0.011 to 0.373 mg/L. In Chunnakam, 60% of sampled wells had nitrate level above the permitted nitrate standard level, and all the wells had elevated oil and grease concentration above the permitted standard limit. Filtration of water through Moringa oleifera leaf powder could significantly reduce the nitrate an oil and grease concentrations, thereby improving the quality of water.

Sensitive scalp is associated with excessive sebum and perturbed microbiome

Sensitive scalp, one of the most frequent complaints among sensitive skin syndrome, has been described as abnormal and unpleasant sensory reactions of the scalp to environmental stimulus. However, the symptoms are usually objective and hard to diagnose. This study aimed to reveal the biophysical properties and etiology of sensitive scalp. Sixty-two healthy female subjects were enrolled and divided into nonsensitive scalp (NS) and sensitive scalp (SS) groups according to questionnaires. Noninvasive instruments were used to measure biophysical properties. Ultra-performance liquid chromatography-tandem mass spectrometry and gas chromatography mass spectrometry were introduced to quantify skin lipids profiles, and 16S rRNA sequencing was used to detect the composition of bacteria. Sensitive scalp showed elevated pH level, more irritated skin, and more fluorescence of porphyrins. Increased sebum production was found in SS group at occiput, among which free fatty acids, cholesteryl ester, and squalene were significantly in higher amount compared with NS. SS also had significantly higher percentage of Propionibacterium, and lower bacterial diversity. Taken together, sensitive scalp showed disrupted barrier function, abnormal sebum amount and composition, as well as perturbed microbiome, which might be the direct cause. Products targeting these features could be helpful for the treatment of sensitive scalp.