Primary Aggregation Research Articles

Investigating economic growth and natural resource dependence: An asymmetric approach in developed and developing economies

Economic growth is one of the primary macroeconomic aggregates that governments seek to achieve due to the positive externalities it generates in a nation. Natural resources are one of those factors that can be seen as a blessing or a curse in determining economic growth. Nowadays, it has been shown that countries can base their economic growth on factors other than capital formation and the intensive use of the labour force. Therefore, this research aims to examine the causal link between economic growth and capital formation, the labour force, renewable energy and renewable energy, the technological innovation at a global level and in groups of countries classified according to their level of income, developed and developing countries. Next, second-generation econometric techniques have been used that control the cross-sectional dependence among the countries examined. Then, the long-term coefficients are examined using the Method of Moments Quantile Regression (MMQR). The results find that the regressor variables are positively associated with economic growth, showing heterogeneity in the various quantiles examined. In addition, there is variation in results when examining economic growth by groups of countries, which shows the intensive use of factors. The results obtained reveal several policy implications aimed at sustainable growth in the era of post-COVI-19.

Frustrated Coulombic and Cation Size Effects on Nanoscale Boehmite Aggregation: A Tumbler Small- and Ultra-Small-Angle Neutron Scattering Study

To better understand the effects of solution chemistry on particle aggregation in the complex legacy tank wastes at the Hanford (WA) and Savannah River (SC) sites, we have performed a series of tumbler small- and ultra-small-angle neutron scattering experiments on 20 wt % solid slurries of nanoparticulate aluminum oxyhydroxide (boehmite) with M1+ nitrates of various concentrations and radii. The solutes consisted of H, Li, Na, K, and Rb nitrates at 10–5, 10–3, 10–1, 2, and 4 molal (m) concentrations, as well as in pure H2O. Synthetic boehmite nanoparticles were used with a size range from ∼20 to 30 nm. Tumbler cells were used to keep the solids from settling. Although particles initially form individual rhombohedral platelets, once placed in solution, they quickly form well-bonded stacks, primary aggregates, up to ∼1500 Å long, and a second level of aggregates whose concentration and structure vary as a function of cation type and concentration. Aggregation generally increases with increased solute concentration and with cation radius up to a concentration somewhat above 10–1 m, at which point the trend reverses. Primary aggregates become more rodlike and larger. The Kirkwood-like reversal probably reflects a change from Derjaguin–Landau–Verwey–Overbeek (DLVO)/Debye behavior controlled by surface chemistry to a frustrated Coulombic system controlled by the solution structure. These data suggest that an understanding of the effects of salt concentration and chemistry on nanoparticle aggregate structures provides useful physical insights into the microscopic origin of slurry rheology in the Hanford and Savannah River legacy wastes.

Molecular aggregation via partial Gal removal affects physicochemical and macromolecular properties of tamarind kernel polysaccharides

The role of molecular aggregation was investigated on physicochemical and macromolecular properties of tamarind kernel polysaccharides via partial degalactosylation (TKPs vs. CTKPs). From the results, their main structural characteristics remained when partially degalactosylated, while primary aggregates as fundamental solution behavior were dynamically converted into higher aggregated forms. Micromorphologically, their conformational changes in different forms of crimping and aggregation could be further promoted by partial Gal removal to assemble on larger scales via hydrophobic interactions. Obviously, the aggregation role was unignorable, especially after partial degalactosylation, which affected TKPs and CTKPs differently concerning viscous behaviors, macromolecular characteristics, amorphous-crystalline transition and thermal stability, probably related to distinctiveness in polymerization degree, chemical structure, conformational entropy, solvent-solute interactions, specific intermolecular associations, etc. Therefore, molecular aggregation in tamarind kernel polysaccharides via specific Gal tailoring could be potential in applicable fields, such as postsurgical adhesion, packaging material design and plasma lipid metabolism.

A re-examination of the liquidus surface of the Al–Fe–Ti system

Abstract The liquidus surface of the Al –Fe –Ti system has been reexamined. 34 different alloys have been studied by differential thermal analysis, and the temperatures of invariant reactions have been determined. By examining the as-cast samples by optical microscopy, X-ray diffraction and energy-dispersive spectrometry in a scanning electron microscope, the crystal structures and chemical compositions of the primary phases and two-phase aggregates have been established. In some cases, additional investigations were carried out in the transmission electron microscope. From the combined results of these investigations the solidification paths of the alloys were established leading to a revised representation of the liquidus surface of the Al –Fe –Ti system. A reaction scheme has been set up which shows phase equilibria that are consistent with previous solid-state isothermal sections.

Iron/titanium oxide-biochar (Fe2TiO5/BC): A versatile adsorbent/photocatalyst for aqueous Cr(VI), Pb2+, F- and methylene blue

This is the first report of the metal Fe-Ti oxide/biochar (Fe2TiO5/BC) composite for simultaneous removal of aqueous Pb2+, Cr6+, F- and methylene blue (MB). Primary Fe2TiO5 nano particles and aggregates were dispersed on a high surface area Douglas fir BC (∼700 m2/g) by a simple chemical co-precipitation method using FeCl3 and TiO(acac)2 salts treated by base and heated to 80 °C. This was followed by calcination at 500 °C. This method previously was used without BC to make the neat mixed oxide Fe2TiO5, exhibiting a lower energy band gap than TiO2. Adsorption of Cr(VI), Pb(II), fluoride, and MB on Fe2TiO5/BC was studied as a function of pH, equilibrium time, initial adsorbate concentration, and temperature. Adsorption isotherm studies were conducted at 5, 25, and 45 ℃ and kinetics for all four adsorbates followed the pseudo second order model. Maximum Langmuir adsorption capacities for Pb2+, Cr6+, F- and MB at their initial pH values were 141 (pH 2), 200 (pH 5), 36 (pH 6) and 229 (pH 6) mg/g at 45 ℃ and 114, 180, 26 and 210 mg/g at 25 ℃, respectively. MB was removed from the water on Fe2TiO5/BC by synergistic adsorption and photocatalytic degradation at pH 3 and 6 under UV (365 nm) light irradiation. Cr6+, Pb2+, F-, and MB each exhibited excellent removal capacities in the presence of eight different competitive ions in simulated water samples. The removal mechanisms on Fe2TiO5/BC and various competitive ion interactions were proposed. Some iron ion leaching at pH 3 catalyzed Photo-Fenton destruction of MB. Fe2TiO5, BC, and Fe2TiO5/BC bandgaps were studied to help understand photocatalysis of MB and to advance supported metal oxide photodegradation using smaller energy band gaps than the larger bandgap of TiO2 for water treatment. A long range goal is to photocatalytically destroy some sorbates with adsorbents to avoid the need for regeneration steps.

Mesoarchean melt and fluid inclusions in garnet from the Kangerlussuaq basement, Southeast Greenland

Abstract The present work reports the first anatectic melt inclusions found so far in the Mesoarchean basement in East Greenland. Using optical microscope observations and MicroRaman spectroscopy, we show that garnets in metasedimentary migmatite contain primary polycrystalline aggregates which can be confidently interpreted as former droplets of anatectic melt, i.e. nanogranitoids. In some cases, they coexist with coeval fluid inclusions under conditions of primary fluid-melt immiscibility. The re-evaluation of the metamorphic pressure and temperature conditions with up-to-date phase equilibria modelling, combined with the identification of nanogranitoids and fluid inclusions, suggests metamorphic peak equilibration and partial melting in presence of a COH-fluid at T ~1000°C and P > 7 kbar. To date, this is the oldest verified occurrence of nanogranitoids and fluid-melt immiscibility during garnet growth in a partially molten environment.

Everything You Always Wanted to Know About Organoid-Based Models (and Never Dared to Ask).

Homeostatic functions of a living tissue, such as the gastrointestinal tract, rely on highly sophisticated and finely tuned cell-to-cell interactions. These crosstalks evolve and continuously are refined as the tissue develops and give rise to specialized cells performing general and tissue-specific functions. To study these systems, stem cell–based in vitro models, often called organoids, and non–stem cell–based primary cell aggregates (called spheroids) appeared just over a decade ago. These models still are evolving and gaining complexity, making them the state-of-the-art models for studying cellular crosstalk in the gastrointestinal tract, and to investigate digestive pathologies, such as inflammatory bowel disease, colorectal cancer, and liver diseases. However, the use of organoid- or spheroid-based models to recapitulate in vitro the highly complex structure of in vivo tissue remains challenging, and mainly restricted to expert developmental cell biologists. Here, we condense the founding knowledge and key literature information that scientists adopting the organoid technology for the first time need to consider when using these models for novel biological questions. We also include information that current organoid/spheroid users could use to add to increase the complexity to their existing models. We highlight the current and prospective evolution of these models through bridging stem cell biology with biomaterial and scaffold engineering research areas. Linking these complementary fields will increase the in vitro mimicry of in vivo tissue, and potentially lead to more successful translational biomedical applications. Deepening our understanding of the nature and dynamic fine-tuning of intercellular crosstalks will enable identifying novel signaling targets for new or repurposed therapeutics used in many multifactorial diseases.

THE NEW CARBONACEOUS XENOLITH K4 AND ITS NATURE IN THE ORDINARY KRYMKA METEORITE (LL3.1)

A study of the structural, mineralogical and chemical properties of another carbonaceous xenolith (K4) occurring in the Krymka chondrite (LL3.1) was made. The xenolith does not correspond to any known chemical sub-group of carbonaceous chondrites in terms of chemical composition and certain mineralogical characteristics, although its fine-grained component is similar to that of CI chondrites. Presence of graphite microcrystals makes the xenolith K4 similar to the Krymka xenoliths K1, K3, and Gr1-Gr7. Xenolith K4 has large amounts of iron sulfide. This may possibly be due to a nonuniform distribution of mineral fractions in a dusty component of the protoplanetary nebula, which could have both a local and more widespread character. During a pre-agglomeration period, K4 accumulated on its surface partially oxidized mineral dust in the same region of the gas-dust protoplanetary nebula as other xenoliths and chondrules of the Krymka meteorite. The evolution of xenolith K4 is generally similar to that of other Krymka graphite-bearing xenoliths, but differs in the relationship among minerals in the primary dusty aggregates. These features determined its distinct chemical and mineralogical characteristics and indicate mineralogical heterogeneity in the dusty component at the micro-level during the pre-accretional period of a mineral material development of the Solar system.

Structural evolution during gelation of pea and whey proteins envisaged by time-resolved ultra-small-angle x-ray scattering (USAXS)

Hydrogels from plant proteins commonly exhibit inferior gel strength compared to those from dairy proteins partially due to their distinct gel networks. How protein aggregates to form such networks in response to heat remains largely unknown. In here, pea (PPI) and whey (WPI) protein isolate gels were produced at the same protein content and similar heating/cooling rate. The process was monitored using rheology, microscopy and in situ ultra-small-angle x-ray scattering (USAXS). Rheology showed an initial decrease in G′ and G″ in PPI followed by a steady increase when the temperature surpassed ∼60 °C whereas a much higher temperature (∼80 °C) was required for WPI, both using 2 °C/min heating rate. Microscopy showed a coarse and heterogenous network in PPI, whereas for WPI, the network was finer and more continuous. In both gels, nano-sized spherical or ellipsoidal particles were present as the basic constituents. USAXS found individual protein was dominant in PPI or WPI solution at temperature below 57 °C. Their proportions decreased together with appearance of aggregates with an average Rg of 9–10 nm in PPI and 6–7 nm in WPI at higher temperature. The size of the aggregates changed slightly during further heating and cooling, but their proportions increased. Power law exponents revealed the aggregates were mass fractals for WPI and PPI gels, and they became more compact during heating. Our findings suggested formation of primary aggregates in protein gel networks is a more organized process and provided theoretical guidance for production of high protein food gels with desirable texture.

Study on the Effect of Recycled Coarse Aggregate on the Shrinkage Performance of Green Recycled Concrete

Shrinkage property is a significant indicator of the durability of concrete, and the shrinkage of green recycled concrete is particularly problematic. In this paper, construction waste was crushed and screened to generate simple-crushed recycled coarse aggregate (SCRCA). The SCRCA was then subjected to particle shaping to create primary particle-shaped recycled coarse aggregate (PPRCA). On this basis, the PPRCA was particle-shaped again to obtain the secondary particle-shaped recycled coarse aggregate (SPRCA). Under conditions where the dosage of cementitious material is 300 kg/m3 and the sand rate is 38%, a new high-belite sulphoaluminate cement (HBSAC) with low carbon emission and superior efficiency was used as the basic cementitious material. Taking the quality of recycled coarse aggregate (SCRCA, PPRCA, and SPRCA) and the replacement ratio (25%, 50%, 75%, and 100%) as the influencing factors to prepare the green recycled concrete, the workability and shrinkage property of the prepared concrete were analyzed. The results show that the water consumption of green recycled concrete decreases as the quality of the recycled coarse aggregate (RCA) increases and the replacement ratio decreases, provided that the green recycled concrete achieves the same workability. With the improvement of RCA quality and the decrease of replacement ratio, the shrinkage of recycled concrete decreases. The shrinkage performance of green recycled concrete configured with the SPRCA completely replacing the natural coarse aggregate (NCA) is basically the same as that of the natural aggregate concrete (NAC).

Rubberized Geopolymer Composites: Value-Added Applications

The discovery of an innovative class of inorganic polymers has brought forth a revolution in the history of construction technology. Now, no energy-intensive reactions at elevated temperatures are essential, as found in the case of contemporary cement production. In addition to their attributes of low energy and a mitigated carbon footprint, geopolymeric composites can incorporate diversely originated and profound wastes in their manufacturing. As of today, profoundly accessible landfills of rubber tyre waste negatively impact the environment, water, and soil, with many health hazards. Their nonbiodegradable complex chemical structure supports recycling, and toxic gases are emitted by burning them, leading to aesthetic issues. These, altogether, create great concern for well-thought-out disposal methods. One of the achievable solutions is processing this waste into alternative aggregates to thus generate increased economic value whilst reducing primary aggregate consumption through the incorporation of these vast automobile solid wastes in the manufacturing of geopolymer construction composites, e.g., binders, mortar, concrete, etc., produced through the process of geopolymerization as a replacement for natural aggregates, providing relief to the crisis of the degradation of restricted natural aggregate resources. Currently, tyre rubber is one of the most outstanding materials, extensively employed in scores of engineering applications. This manuscript presents a state-of-the-art review of value-added applications in the context of rubberized geopolymer building composites and a review of past investigations. More significantly, this paper reviews rubberized geopolymer composites for their value-added applications.

Spindle-like-aggregating behavior of hydroxyapatite nanorods in polyacrylic acid aqueous system

The aggregating behavior of hydroxyapatite (HAP) nanorods plays a central role in the mechanism of biomimetic mineralization. In this study, the spindle-like aggregating behavior of hydroxyapatite (HAP) nanorods was studied by ultrasonically dispersing HAP in a polyacrylic acid (PAA) aqueous system. Unlike the quick aggregation and precipitation of HAP nanorods without PAA, the spindle-like primary aggregations formed herein could be suspended in water with good stability. The preferential adsorption of PAA on the side surface of HAP nanorods generated steric repulsion opposite to the van der Waals interaction in the radial direction. Accordingly, with an increase in the molar ratio of PAA[-COOH-]/HAP, the HAP nanorods showed a tendency to form spindle-like primary aggregations with decreased diameter and increased aspect ratio. The resulting aggregates possessed sufficient repulsion (steric repulsion and electric double layer repulsion) to overcome van der Waals interactions to remain suspended and dispersed. This study revealed the mechanism of aggregating HAP nanorods into spindle-like aggregates by extended Derjaguin–Landau–Verwey–Overbeek theory, including the steric stabilization mode. We believe that this study will facilitate the ordered structuring of minerals in hard-tissue mineralization processes.

Dietary Intake Quality Is Affected by Knowledge and Dietary Intake Frequency among Pregnant Women in Muntinlupa, Philippines: A Cross-Sectional Study

Improving the nutrition of pregnant women is essential in reducing maternal and child mortality, which is one of the global nutritional goals of 2025. This study evaluated the factors related to the quality of dietary intake among pregnant women in Muntinlupa, Philippines. We conducted a cross-sectional study of 280 pregnant women at a hospital in Muntinlupa from March 2019 to August 2019 using questionnaires. After the primary aggregation, multivariate logistic regression analysis was used to identify factors associated with the quality of dietary intake in pregnant women. Approximately half of the women (46.4%, n = 130) had a low dietary diversity during pregnancy. Less than 30% of the respondents consumed beans, soybean products, and nuts. In the logistic regression analysis, poor maternal knowledge of nutritional sources to prevent anemia (odds ratio (OR) 4.25, 95% confidence interval (CI) 1.47–12.32, p = 0.01) and less frequent meal consumption (OR 2.15, 95% CI 1.08–4.29, p = 0.03) were significantly associated with poor dietary diversity. Our findings are crucial because they suggest that increasing the knowledge of pregnant women about good nutrition and ensuring that dietary intake is frequent and adequate through antenatal care can improve the nutrition of pregnant women.

The Use of Recycled and Secondary Aggregates to Achieve a Circular Economy within Geotechnical Engineering

The construction industry’s current dependence on primary aggregates is unsustainable as these are non-renewable resources and the consumption of these materials has a high environmental impact. The global annual production of primary aggregates is estimated to be 50 billion tonnes. In Europe, where 2 billion tonnes of primary aggregates are produced annually, approximately 90% of aggregates are utilised by the construction industry, whilst over 1 Gt of waste are sent to landfill; in the UK, 44% of landfilled waste arises from the construction industry. The drive to adopt a circular economy necessitates changes in resource use (including non-renewable aggregates). Recycling wastes, such as aggregates, could help this situation; whilst this concept is not new, it does not appear to have been widely embraced in geotechnical engineering. The aim of this paper is to highlight the benefits of increasing the use of alternative aggregates as this would enable the reserves of primary aggregates to be better maintained and less material would be landfilled—a win-win situation and a contributing step towards developing a truly circular economy.

Structure-Activity Relationship Analysis of Analogs of Rhosin, a RhoA Inhibitor, Reveals a New Generation of Improved Antiplatelet Agents

Platelet activation and aggregation play a key role in mediating hemostasis and thrombosis. The antiplatelet therapies currently available in the market are associated with a high risk of hemorrhage and are mostly irreversible in suppressing platelet activity; hence, there is a need to develop better therapeutic agents. Previous genetic and pharmacological studies have implicated the small GTPase RhoA in multiple platelet signaling pathways. We devised a lead RhoA activity-specific inhibitor, Rhosin/G04, based on the structure-function relationship of RhoA interaction with its activator, guanine nucleotide exchange factor (GEF) (Figure 1A). Rhosin/G04 binds to RhoA directly with micromolar affinity at a surface groove that is essential for GEF recognition and blocks GEF-mediated GTP loading to RhoA. Rhosin/G04 inhibits platelet spreading on fibrinogen and thrombin-induced platelet aggregation, mimicking effects of RhoA gene targeting. In the current work, we have utilized the inhibitory activity of G04 for platelet activation and its biochemical activity to define its structure-activity relationship (SAR) and to understand its mechanism of action in an effort to improve efficacy and druggability.The structure of G04 in a groove of RhoA interaction was hypothesized based on the docking studies using Molsoft ICM-Pro. Cincinnati Children's Hospital Medical Center's compound library of over 360,000 chemicals was scanned for G04 analogs by similarity and substructure searches. In the initial screen, a human platelet aggregation assay was performed at both a low concentration (1 µg/ml) and a high concentration (5 µg/ml) of collagen. The first round similarity search resulted in a set of 7 compounds (Set-1), from which, compound 177629 showed significantly enhanced potency relative to G04 (Figure 1B). The second round of similarity searches for compounds more closely related to 177629 (Set-2) identified 14 compounds. The third-round search for other related compounds (Set-3) led to 9 additional compounds that add to the understanding of the SAR. The compounds that showed enhanced antiplatelet activity were examined for their potency and selectivity in in vitro biochemical binding assays and in suppressing RhoA-GTP formation and downstream phosphorylation of myosin light chain (p-MLC) signaling in platelets. The active compounds were further examined for their anti-platelet activities under diverse stimuli including thrombin, ADP, U46619 (a stable thromboxane receptor agonist), and arachidonic acid.The most active compounds from Set-1, Set-2, and Set-3 inhibited platelet aggregation by at least 70% and showed IC 50 values below 6 µM. Of these compounds, 12 showed significantly greater potency than the initial compound, G04. The most active compounds were 177618, 177619, 177628, 177629, 177633, and 177634. These compounds specifically inhibited RhoA activity and blocked p-MLC. SAR analyses led us to believe that the quinoline is optimally attached to the hydrazine at the 4-position. The halogen (choloro- or trifluoromethyl-) substitution at the 7- or 8- position improved activity, and the 7- position may be slightly favored. The aryl group is considerably variable with similar potency between the indole, methylphenyl, and dichlorophenyl- groups.Rhosin/G04 is the R enantiomer (i.e. Rhosin is R-G04), so its S enantiomer, S-G04 was also evaluated (Figure 1C). S-G04 is significantly more potent than R-G04 in inhibiting collagen-stimulated RhoA-GTP formation and aggregation of platelets, and its effect is completely reversible by washing the platelets. Finally, R-G04 and S-G04 showed differential inhibition of arachidonic acid and U46619 stimulated primary and secondary aggregation, highlighting the potential utilities of the inhibitors in dissecting different platelet activation mechanisms. S-G04 is active in inhibiting thrombin, ADP, U46619, and arachidonic acid-mediated platelet activation at submicromolar concentration, suggesting a broad role of RhoA signaling in integrating platelet signal cross talk.In summary, evaluation of Rhosin/R-G04 analogs in a platelet activity screen identified a new generation of improved small-molecule RhoA inhibitors, including an enantiomer with significantly improved efficacy. These analog studies of novel anti-platelet agents provide a new approach to effectively and reversibly manipulate platelet activities. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Optimised design of concrete recycling networks: The case of North Rhine-Westphalia.

In Germany, construction and demolition waste is either landfilled or used for roadworks after being treated in recycling plants. However, recycled concrete aggregates from building demolition can be reused for the construction of new buildings, which allows to close the material loop of concrete. The aim of this study is to develop a decision support system (DSS) in order to investigate the economic impacts and consequences of recycling concrete from building demolition in a closed loop material cycle. To do so, we propose a bi-objective mixed-integer linear optimisation model that provides information on the number and location of installed sorting screens and defines the material flows within a comprehensive regional recycling network covering all processes from building demolition to construction of new buildings. While the economic objective function minimises the total costs of the recycling network, the circularity objective function minimises the amount of primary natural aggregates required for concrete manufacturing. We apply our optimisation model to the German federal state of North Rhine-Westphalia. Results show that under current conditions the manufacturing of concrete with recycled concrete aggregates is economically viable predominantly in areas without local supplies of natural aggregates. In addition, analysis of the trade-offs between the two objectives as well as recommendations on the design of political regulations and economic instruments to foster such recycling networks are presented.

Perception Of People About Effects Of Atal Tunnel At Rohtang On The Life Of Tribal People In Lahaul Area In The State Of Himachal Pradesh- India

The word ‘tribe’ has different connotations for different branches of social sciences. Western anthropologists and sociologists take the term to denote a “primary aggregate of peoples living in a primitive or barbarous condition under a headman or chief”. Indian Constitution assigned special status to the schedule tribes, traditionally referred to as adivasi, vanavasi, tribes or tribals. The Tribal People of Lahaul have been experiencing geographical isolation as the area remain inaccessible for more than six months from the month of November to April every year due to closing of Rohtang Pass the only way to the area. Having difficult geographic environment i.e. mountainous and rugged terrain, extreme cold and dry agro climatic conditions, non- industrialization and limited basic infrastructure facilities at village level Lahaul tribal area of Himachal Pradesh. However, after opening the Atal Tunnel at Rohtang a new era of development, accessibility and connectivity started in this area. The present Paper is to study the perception of these tribal people about effect of Atal tunnel in Lahaul Tribal area. A questionnaire has been prepared and questions related to the effect of opening the tunnel on their Social, Cultural, economic life, opportunities, Challenges and tribal identity has been asked and recoded for analysis. For this purpose the study area has been divided into five physiographic units for sampling at village level. These micro physiographic units are demarcated by ridge line of mountains, drainage network and tehsils boundaries. Considering the geographic spread the purposive random sampling technique will be used for collecting the primary data. In total, 39 sample villages and about 585 households which constitute approximately 15% of total population surveyed for the present study.

Long‐term effect of sugarcane residue management and chemical fertilization on soil physical properties in South Africa

AbstractSugarcane (Saccharum officinarum L.), an intensive, long‐term, monoculture, economical crop in South Africa, is known to degrade soil characteristics. Soil structure, a key indicator of soil health and biomass production potential, is manageable by agricultural practices. This study aims to evaluate the effect of crop residue management practices (mulching, burning with residues scattered or removed) and mineral fertilization (with or without) on soil structure by analyzing soil shrinkage curves (SSCs) and other soil physical and chemical properties in a long‐term sugarcane trial established in 1939. The SSC provides descriptive structural soil data by differentiating and characterizing two pore systems (plasma and structural pores). By analyzing the SSC of 24 plots (four replicates each treatment), residue management and fertilization practices were found to have statistically and physically significant effects on hydrostructural variables. Partial redundancy analysis showed that residue management practices had a slightly higher effect (19% of total variance) on hydrostructural variables compared with fertilization (12%). The main hydrostructural variables representing the management effect were total soil shrinkage, specific volume, and swelling capacity of the plasma, which were higher in mulched and/or unfertilized plots, indicating that soil was less compact, and shrinkage was more intense, including at the plasma level. The stronger structural dynamics and aggregate stability of the soil were explained by the behavior of the primary aggregates (peds), which were more porous and reactive during the drying process. This study highlights the importance of mulching and limited fertilization to maintain soil structure in the long term while still ensuring yield production.

Oceanographic Drivers of Cuvier’s (Ziphius cavirostris) and Sowerby’s (Mesoplodon bidens) Beaked Whales Acoustic Occurrence along the Irish Shelf Edge

Cuvier’s and Sowerby’s beaked whales occur year-round in western Irish waters, yet remain some of the most poorly understood cetaceans in the area. Considering the importance of the area for anthropogenic activities and the sensitivity of beaked whales to noise, understanding their ecology is essential to minimise potential overlaps. To this end, fixed bottom-mounted autonomous acoustic recorders were deployed at 10 stations over four recording periods spanning from May 2015 to November 2016. Acoustic data were collected over 1934 cumulative days, for a total of 7942 h of recordings. To model the probability of presence of Cuvier’s and Sowerby’s beaked whales in the area as a function of oceanographic predictors, we used Generalised Additive Models, fitted with Generalised Estimating Equations to deal with temporal autocorrelation. To reflect prey availability, oceanographic variables acting as proxies of primary productivity and prey aggregation processes such as upwelling events and thermal fronts were selected. Our results demonstrated that oceanographic variables significantly contributed to the occurrence of Cuvier’s and Sowerby’s beaked whales (p-values between <0.001 and <0.05). The species showed similar preferences, with the exception of sdSST. The inclusion of a parameter accounting for the recorders location confirmed the existence of a latitudinal partitioning for those species in the area. This study provides a point of comparison for future research and represents an important step towards a better understanding of those elusive species.

Establishment of chemically oligomerizable TAR DNA-binding protein-43 which mimics amyotrophic lateral sclerosis pathology in mammalian cells

One of the pathological hallmarks of amyotrophic lateral sclerosis (ALS) is mislocalized, cytosolic aggregation of TAR DNA-Binding Protein-43 (TDP-43). Not only TDP-43 per se is a causative gene of ALS but also mislocalization and aggregation of TDP-43 seems to be a common pathological change in both sporadic and familial ALS. The mechanism how nuclear TDP-43 transforms into cytosolic aggregates remains elusive, but recent studies using optogenetics have proposed that aberrant liquid–liquid phase separation (LLPS) of TDP-43 links to the aggregation process, leading to cytosolic distribution. Although LLPS plays an important role in the aggregate formation, there are still several technical problems in the optogenetic technique to be solved to progress further in vivo study. Here we report a chemically oligomerizable TDP-43 system. Oligomerization of TDP-43 was achieved by a small compound AP20187, and oligomerized TDP-43 underwent aggregate formation, followed by cytosolic mislocalization and induction of cell toxicity. The mislocalized TDP-43 co-aggregated with wt-TDP-43, Fused-in-sarcoma (FUS), TIA1 and sequestosome 1 (SQSTM1)/p62, mimicking ALS pathology. The chemically oligomerizable TDP-43 also revealed the roles of the N-terminal domain, RNA-recognition motif, nuclear export signal and low complexity domain in the aggregate formation and mislocalization of TDP-43. The aggregate-prone properties of TDP-43 were enhanced by a familial ALS-causative mutation. In conclusion, the chemically oligomerizable TDP-43 system could be useful to study the mechanisms underlying the droplet-aggregation phase transition and cytosolic mislocalization of TDP-43 in ALS and further study in vivo.TDP-43 is the primary protein aggregate in amyotrophic lateral sclerosis (ALS), and its mislocalization from nucleus is a hallmark of ALS pathology whose mechanisms remain unclear. In this study, the authors report a novel chemically oligomerizable TDP-43 system. Induction of TDP-43 oligomerization mimics ALS pathology such as mislocalization of TDP-43 and recruitment of critical proteins into the aggregates.