Natural coagulates for wastewater treatment; a review for application and mechanism

The increase of water demand and wastewater generation is among the global concerns in the world. The less effective management of water sources leads to serious consequences, the direct disposal of untreated wastewater is associated with the environmental pollution, elimination of aquatic life and the spread of deadly epidemics. The flocculation process is one of the most important stages in water and wastewater treatment plants, wherein this phase the plankton, colloidal particles, and pollutants are precipitated and removed. Two major types of coagulants are used in the flocculation process included the chemical and natural coagulants. Many studies have been performed to optimize the flocculation process while most of these studies have confirmed the hazardous effects of chemical coagulants utilization on the ecosystem. This chapter reviews a summary of the coagulation/flocculation processes using natural coagulants as well as reviews one of the most effective natural methods of water and wastewater treatment

Birth cohort effects on the quantity and heritability of alcohol consumption in adulthood : a Finnish longitudinal twin study

Aims To estimate birth cohort effects on alcohol consumption and abstinence in Finland and to test differences between birth cohorts in genetic and environmental sources of variation in Finnish adult alcohol use. Design The Older Finnish Twin Cohort longitudinal survey study 1975-2011. Setting Finland. Participants A total of 26 121 same-sex twins aged 18-95 years (full twin pairs at baseline n = 11 608). Measurements Outcome variables were the quantity of alcohol consumption (g/month) and abstinence (drinking zero g/month). Predictor variables were 10-year birth cohort categories and socio-demographic covariates. In quantitative genetic models, two larger cohorts (born 1901-20 and 1945-57) were compared. Findings Multi-level models in both sexes indicated higher levels of alcohol consumption in more recent birth cohorts and lower levels in earlier cohorts, compared with twins born 1921-30 (all P < 0.003). Similarly, compared with twins born 1921-30, abstaining was more common in earlier and less common in more recent cohorts (all P < 0.05), with the exception of men born 1911-20. Birth cohort differences in the genetic and environmental variance components in alcohol consumption were found: heritability was 21% [95% confidence interval (CI) = 0-56%] in the earlier-born cohort of women [mean age 62.8, standard deviation (SD) = 5.3] and 51% (95% CI = 36-56%) in a more recent cohort (mean age 60.2, SD = 3.7) at the age of 54-74. For men, heritability was 39% (95% CI = 27-45%) in both cohorts. In alcohol abstinence, environmental influences shared between co-twins explained a large proportion of variation in the earlier-born cohort (43%, 95% CI = 23-63%), whereas non-shared environmental (54%, 95% CI = 39-72%) and additive genetic influences (40%, 95% CI = 13-61%) were more important among more recent cohorts of men and women. Conclusion The contribution of genetic and environmental variability to variability in alcohol consumption in the Finnish population appears to vary by birth cohort.Peer reviewe

Mechanical properties and microstructure of additively manufactured stainless steel with laser welded joints

Powder bed fusion (PBF) is a commonly employed metal additive manufacturing (AM) process in which components are built, layer-by-layer, using metallic powder. The component size is limited by the internal build volume of the employed PBF AM equipment; the fabrication of components larger than this volume therefore requires mechanical joining methods, such as laser welding. There are, however, very limited test data on the mechanical performance of PBF metal with laser welded joints. In this study, the mechanical properties of PBF built 316L stainless steel parts, joined together using laser welding to form larger components, have been investigated; the microstructure of the components has also been examined. 33 PBF 316L stainless steel tensile coupons, with central laser welds, welded using a range of welding parameters, and with coupon half parts built in two different orientations, were tested. The porosity, microhardness and microstructure of the welded coupons, along with the widths of the weld and heat-affected zone (HAZ), were characterised. The PBF base metal exhibited a typical cellular microstructure, while the weld consisted of equiaxed, columnar and cellular dendrite microstructures. Narrow weld regions and HAZs were observed. The PBF base metal was found to have higher proof and ultimate strengths, but a similar fracture strain and a lower Young’s modulus, compared with conventionally manufactured 316L stainless steel. The strengths were dependent on the build direction – the vertically built specimens showed lower proof strengths than the horizontal specimens. The laser welds generally exhibited lower microhardness, proof strengths and fracture strains than the PBF base metal which correlated with the observed structure. This work has demonstrated that PBF built parts can be joined by laser welding to form larger components and provided insight into the resulting strength and ductility

Loss of muscleblind splicing factor shortens Caenorhabditis elegans lifespan by reducing the activity of p38 MAPK/PMK-1 and transcription factors ATF-7 and Nrf/SKN-1

Muscleblind-like splicing regulators (MBNLs) are RNA-binding factors that have an important role in developmental processes. Dysfunction of these factors is a key contributor of different neuromuscular degenerative disorders, including Myotonic Dystrophy type 1 (DM1). Since DM1 is a multisystemic disease characterized by symptoms resembling accelerated aging, we asked which cellular processes do MBNLs regulate that make them necessary for normal lifespan. By utilizing the model organism Caenorhabditis elegans, we found that loss of MBL-1 (the sole ortholog of mammalian MBNLs), which is known to be required for normal lifespan, shortens lifespan by decreasing the activity of p38 MAPK/PM K-1 as well as the function of transcription factors ATF-7 and SKN-1. Furthermore, we show that mitochondrial stress caused by the knockdown of mitochondrial electron transport chain components promotes the longevity of mbl-1 mutants in a partially PMK-1-dependent manner. Together, the data establish a mechanism of how DM1-associated loss of muscleblind affects lifespan. Furthermore, this study suggests that mitochondrial stress could alleviate symptoms caused by the dysfunction of muscleblind splicing factor, creating a potential approach to investigate for therapy.Peer reviewe

Broad rim lesions are a new pathological and imaging biomarker for rapid disease progression in multiple sclerosis

Current multiple sclerosis (MS) treatments reduce relapse activity but have limited impact on disease progression. Clinical trials targeting progression often fail because of insufficient understanding of its underlying mechanisms. This study analyzed a clinically well-characterized MS autopsy cohort from the Netherland Brain Bank (186 individuals) from which we selected donors exhibiting opposite disease trajectories of slow versus rapid progression. We performed extensive unbiased histology and spatial transcriptomics, which unveiled a distinct MS lesion type marked by an extensive myeloid cell rim with cellular and transcriptional signatures of innate immune activation, inflammatory cytokine production, unfolded protein response and apoptosis. Presence of this particular lesion type was linked to rapid disease progression. An independent translocator protein 18-kDa positron emission tomography study (114 individuals) validates the association between lesions with a broad myeloid cell rim and disease progression in individuals with MS. Our findings offer crucial insights into the mechanisms behind MS progression, identifying broad rim lesions as a biomarker for rapid disease progression and potentially guiding patient selection for future therapeutic trials targeting central nervous system intrinsic inflammation.</p

Vertical profiles of sub-3nm particles over the boreal forest

This work presents airborne observations of sub-3 nm particles in the lower troposphere and investigates new particle formation (NPF) within an evolving boundary layer (BL). We studied particle concentrations together with supporting gas and meteorological data inside the planetary BL over a boreal forest site in Hyytiala, southern Finland. The analysed data were collected during three flight measurement campaigns: May-June 2015, August 2015 and April-May 2017, including 27 morning and 26 afternoon vertical profiles. As a platform for the instrumentation, we used a Cessna 172 aircraft. The analysed flight data were collected horizontally within a 30 km distance from SMEAR II in Hyytiala and vertically from 100 m above ground level up to 2700 m. The number concentration of 1.5-3 nm particles was observed to be, on average, the highest near the forest canopy top and to decrease with increasing altitude during the mornings of NPF event days. This indicates that the precursor vapours emitted by the forest play a key role in NPF in Hyytiala. During daytime, newly formed particles were observed to grow in size and the particle population became more homogenous within the well-mixed BL in the afternoon. During undefined days with respect to NPF, we also detected an increase in concentration of 1.5-3 nm particles in the morning but not their growth in size, which indicates an interrupted NPF process during these undefined days. Vertical mixing was typically stronger during the NPF event days than during the undefined or non-event days. The results shed light on the connection between boundary layer dynamics and NPF.Peer reviewe

Natalizumab treatment reduces microglial activation in the white matter of the MS brain

ObjectiveTo evaluate whether natalizumab treatment reduces microglial activation in MS.MethodsWe measured microglial activation using the 18-kDa translocator protein (TSPO)-binding radioligand [C-11] PK11195 and PET imaging in 10 patients with MS before and after 1 year treatment with natalizumab. Microglial activation was evaluated as the distribution volume ratio (DVR) of the specifically bound radioligand in brain white and gray matter regions of interest. MRI and disability measurements were performed for comparison. Evaluation was performed identically with 11 age-and sex-matched patients with MS who had no MS therapy.ResultsNatalizumab treatment reduced microglial activation in the normal-appearing white matter (NAWM; baseline DVR vs DVR after 1 year of treatment 1.25 vs 1.22, p = 0.014, Wilcoxon) and at the rim of chronic lesions (baseline DVR vs DVR after 1 year of treatment 1.24 vs 1.18, p = 0.014). In patients with MS with no treatment, there was an increase in microglial activation at the rim of chronic lesions (1.23 vs 1.27, p = 0.045). No alteration was observed in microglial activation in gray matter areas. In the untreated patient group, higher microglial activation at baseline was associated with more rapid disability progression during an average of 4 years of follow-up.ConclusionsTSPO-PET imaging can be used as a tool to assess longitudinal changes in microglial activation in the NAWM and in the perilesional areas in the MS brain in vivo. Natalizumab treatment reduces the diffuse compartmentalized CNS inflammation related to brain resident innate immune cells

Removal of organic matter from reservoir water: mechanisms underpinning surface chemistry of natural adsorbents

One of the key challenges in water treatment industry is the removal of organic compounds by cost-effective methods. This study evaluated the adsorptive removal of dissolved organic carbon (DOC) from reservoir water using fuller’s earth (FE) in comparison with natural (SQ) and modified quartz (MSQ) sands. The removal capacities of FE at different contact times, pH levels, adsorbent dosages and initial DOC concentrations were compared with both the quartz sands. The optimum DOC removals by FE and SQs were achieved at contact time of 60 and 30 min, pH level of 6 and 4, and at adsorbent dose of 1.5 g/150 mL and 10 g/100 mL, respectively. The adsorption capacity of FE (1.05 mg/g) was much higher compared to the MSQ (0.04 mg/g) and SQ (0.01 mg/g). Adsorption equilibrium data better fitted to the Freundlich model than to the Langmuir model, suggesting that adsorption occurred primarily through multilayer formation onto the surfaces of FE and SQ. The pseudo-second-order model described the uptake kinetics more effectively than the pseudo-first-order and intra-particle diffusion models, indicating that the mechanism was primarily governed by chemisorption. These observations were well supported by the physiochemical characteristics and charge behaviour of the adsorbents. In mass-transfer study, the results of liquid film diffusion model showed that the adsorption of DOC on FE was not controlled by film diffusion, but other mechanisms also played an essential role. This study demonstrates that FE is an effective adsorbent for the removal of DOC in surface water treatment

SN 2023tsz: a helium-interaction-driven supernova in a very low-mass galaxy

SN 2023tsz is a Type Ibn supernova (SN Ibn), an uncommon subtype of stripped-envelope core-collapse supernovae (SNe), discovered in an extremely low-mass host. SNe Ibn are characterized by narrow helium emission lines in their spectra and are believed to originate from the collapse of massive Wolf–Rayet (WR) stars, though their progenitor systems still remain poorly understood. In terms of energetics and spectrophotometric evolution, SN 2023tsz is largely a typical example of the class, although line profile asymmetries in the nebular phase are seen, which may indicate the presence of dust formation or unshocked circumstellar material. Intriguingly, SN 2023tsz is located in an extraordinarily low-mass host galaxy that is in the second percentile for stripped-envelope SN host masses and star formation rates (SFRs). The host has a radius of 1.0 kpc, a g-band absolute magnitude of -12.72 ± 0.05$, and an estimated metallicity of log (Z*/ Z⊙)≈ -1.6. The SFR and metallicity of the host galaxy raise questions about the progenitor of SN 2023tsz. The low SFR suggests that a star with sufficient mass to evolve into a WR would be uncommon in this galaxy. Further, the very low metallicity is a challenge for single stellar evolution to enable H and He stripping of the progenitor and produce an SN Ibn explosion. The host galaxy of SN 2023tsz adds another piece to the ongoing puzzle of SNe Ibn progenitors, and demonstrates that they can occur in hosts too faint to be observed in contemporary sky surveys at a more typical SN Ibn redshift