Modal Size Research Articles

Thermal behavior of construction and demolition waste-based geopolymer

Unsorted Construction and Demolition Waste (CDW) from residential building was tested as solid precursor for obtaining eco-sustainable alkali activated materials with potential applications in the building industry. Suitable reactive systems for material consolidation were tested, including alkaline solutions of sodium hydroxides and/or silicates at different concentrations. Metakaolin (MK) was also tested as an additional precursor together with CDW in different ratios to optimize geopolymerization. An MK/CDW weight ratio of 40/60 and sodium silicate as alkaline activator allowed the production of a well-reacted and cohesive material, with a bulk density of 1.35 g/cm3, a monomodal mesoporosity with a modal pore size of 0.0214 µm (open porosity ∼42 vol%), and a compressive strength of 25 MPa, thus showing similar features to those of pure metakaolin based-geopolymers. Thermal characterization was performed up to 1000°C showing that the material can exhibit thermal stability up to 650°C. Above that temperature a shrinkage due to viscous flow occurred, followed by an expansion over 750°C with the formation of macropores and dense struts. Based on these results, the developed CDW-based geopolymer has the potential for use in green building applications, with adequate thermal stability up to medium-high temperatures.

Tidal influence on Fish Faunal Distribution and Species Diversity in Kakum Estuary, Ghana

Estuarine and coastal areas are complex and dynamic aquatic environments. In such an area, where river water mixes with seawater, a large number of physical and chemical processes take place, which may influence water quality thereby affecting the distribution and diversity of the biota. The study was conducted in the transition period of dry and wet conditions from February to May 2018. The influence of low and high tides on the hydrographic parameters such as salinity, dissolved oxygen, and water temperature in the three sampling stations was analyzed in relation to fish faunal distribution and species diversity of the estuary. The common fish species in the estuary were juveniles of Sarotherodon melanotheron and Mugil cephalus, Liza falcipinnis and the crab Callinectes amnicola. These species were encountered during both low and high tides in all sampling stations, which indicates their adaptation to a broader range of hydrographic conditions. The majority of species encountered were juveniles. Although most of the fish species were marine in origin, some including Tilapia zillii, Hemichromis fasciatus and Apolochelichthys spilauchen were freshwater in origin whilst, S. melanotheron is a resident fish species in the estuary. Length-frequency distribution and length-weight relationships of S. melanotheron, T. zillii, L. falcipinnis, Mugil cephalus, and Eucinosthomus melanopterus which were the five most dominant fish species during the period of study in Kakum estuary were analyzed. The modal sizes of the dominant fish species were mainly juveniles in the length-frequency distribution. The length-weight relationships of S. melanotheron, L. falcipinnis and M. cephalus showed allometric growth, whereas that of T. zillii and E. melanopterus showed isometric growth. The study, therefore, identified that Kakum estuary is a transitional zone for both marine and freshwater fish species using the estuarine ecosystem as nursery grounds. The presence of marine and freshwater-origin species, and resident species in the estuary further suggest that estuaries are highly dynamic, and slight changes in their environment can cause a great deal of harm to its fish biota.

Geospatial assessment of the cost and energy demand of feedstock grinding for enhanced rock weathering in the coterminous United States

In an effort to mitigate anthropogenic climate impacts the U.S. has established ambitious Nationally Determined Contribution (NDC) targets, aiming to reduce greenhouse gas emissions by 50% before 2030 and achieving net-zero emissions by 2050. Enhanced rock weathering (ERW)—the artificial enhancement of chemical weathering of rocks to accelerate atmospheric CO2 capture—is now widely seen as a potentially promising carbon dioxide removal (CDR) strategy that could help to achieve U.S. climate goals. Grinding rocks to smaller particle size, which can help to facilitate more rapid and efficient CO2 removal, is the most energy-demanding and cost-intensive step in the ERW life cycle. As a result, accurate life cycle analysis of ERW requires regional constraints on the factors influencing the energetic and economic demands of feedstock grinding for ERW. Here, we perform a state-level geospatial analysis to quantify how carbon footprints, costs, and energy demands vary among regions of the coterminous U.S. in relation to particle size and regional electricity mix. We find that CO2 emissions from the grinding process are regionally variable but relatively small compared to the CDR potential of ERW, with national averages ranging between ~5–35 kgCO2 trock−1 for modal particle sizes between ~10–100 μm. The energy cost for feedstock grinding also varies regionally but is relatively small, with national average costs for grinding of roughly 0.95–5.81 $ trock−1 using grid mix power and 1.35–8.26 $ trock−1 (levelized) for solar PV for the same particle size range. Overall energy requirements for grinding are also modest, with the demand for grinding 1 Gt of feedstock representing less than 2% of annual national electricity supply. In addition, both cost and overall energy demand are projected to decline over time. These results suggest that incorporating feedstock grinding into ERW deployment at scale in the coterminous U.S. should generally have only modest impacts on lifecycle emissions, cost-effectiveness, and energy efficiency.

High-fidelity fluid-structure interaction applied to static aeroelasticity in transonic flows

Transonic flows at high Reynolds numbers can lead to high dynamic pressures and, consequently, to aerostructural deflections of aircraft structures. This study aims to develop and validate a high-fidelity static aeroelastic analysis environment that is efficient and that can be used in an industrial setting. The aerodynamics is represented by numerical solutions of the Reynolds-averaged Navier-Stokes equations with appropriate turbulence closures. The load transfer process uses finite element shape functions in order to distribute the aerodynamic loads into the structural discretization. The structural analysis employs a modal basis approach, and a wingtip deflection convergence study is performed to find an adequate modal basis size. Radial basis functions are used for the fluid mesh displacement, and the influence of the support radius is evaluated to determine the optimal values relative to the wing mean aerodynamic chord. The capability is tested using the static aeroelastic benchmarks of the High Reynolds Aerostructural Dynamics Project (HIRENASD) and NASA's Common Research Model (CRM). The static aeroelastic results demonstrate robustness and consistency for the aerodynamic coefficients, pressure distributions, and structural deflection predictions at different normalized dynamic pressure values and grid refinement levels.

Fine‐grained sediment production by endolithic sponges on Caribbean coral reefs

AbstractEndolithic sponges are key players in carbonate cycling on coral reef systems. While their bioerosion of reef framework is relatively well studied, their role in biogenic sediment generation is poorly understood. In this study, the sedimentary attributes and production rates of eight Caribbean endolithic sponge species were characterized. The findings revealed notable species‐specific variations in sediment production rates (range: 1.0–6.3 kg CaCO3 m−2 yr−1), alongside consistency in sediment characteristics (modal sizes ranging from 39 to 48 μm). The species‐specific rates were used to explore reef‐scale variations in sponge‐derived sediment generation across 50 reef sites in the Mexican Caribbean. Significant between‐site variability was observed, with estimated annual sediment production ranging from < 0.01 to 0.84 kg m−2 of reef. Production was primarily driven by sponge abundance, with discernible spatial variations in the contributions of different species, which could be related to variability in local environmental conditions. The rapidity at which these sediment producers can utilize dead coral substrates, coupled with their positive response to the changing marine environment, highlights the growing importance of these sponges in modern degraded Caribbean reef systems.

Differential extracellular vesicle concentration and their biomarker expression of integrin αv/β5, EpCAM, and glypican-1 in pancreatic cancer models

Tumor-derived extracellular vesicles (EVs) show great potential as biomarkers for several diseases, including pancreatic cancer, due to their roles in cancer development and progression. However, the challenge of utilizing EVs as biomarkers lies in their inherent heterogeneity in terms of size and concentration, making accurate quantification difficult, which is highly dependent on the isolation and quantification methods used. In our study, we compared three EV isolation techniques and two EV quantification methods. We observed variations in EV concentration, with approximately 1.5-fold differences depending on the quantification method used. Interestingly, all EV isolation techniques consistently yielded similar EV quantities, overall size distribution, and modal sizes. In contrast, we found a notable increase in total EV amounts in samples from pancreatic cancer cell lines, mouse models, and patient plasma, compared to non-cancerous conditions. Moreover, individual tumor-derived EVs exhibited at least a 3-fold increase in several EV biomarkers. Our data, obtained from EVs isolated using various techniques and quantified through different methods, as well as originating from various pancreatic cancer models, suggests that EV profiling holds promise for the identification of unique and cancer-specific biomarkers in pancreatic cancer.

Reproductive traits of the deep-sea shrimp Plesionika williamsi (decapoda: Pandalidae) from the eastern-central atlantic

The reproductive aspects of all Plesionika species are relatively well known worldwide, except for the deepest species of the genus, Plesionika williamsi, for which little information is available throughout its range. The ovarian maturity, sex ratio, brood size, and size-depth distribution of the deep-sea shrimp Plesionika williamsi (Pandalidae) in the Canary Islands (eastern-central Atlantic) were analysed. Ovigerous females were observed all year round, with the highest number of ovigerous females recorded between July and October. The presence of a greater number of ovigerous females during the summer may reflect a high local availability of food or the optimal abiotic conditions, which are factors with a strong influence on reproduction. The presence of non-ovigerous mature females throughout the year indicates that their resting period in the reproductive cycle occurs asynchronously. The physiological size at first sexual maturity was 19.24 mm in carapace length (CL) and the length at first sexual maturity was estimated at 23.15 mm CL. Estimates of size at first sexual maturity based on ovigerous females describe the result of the reproduction process, whereas size at first sexual maturity based on ovarian maturity deals with physiological preparation for reproduction. The modal size class of egg production was 24–30 mm CL, which yielded 83.22% of the population egg production. Plesionika williamsi is an iteroparous species that can produce small eggs during egg extrusion. The mean number of external embryos carried by females was 3048 and can be considered a true approximation of the number of larvae released in each batch, which depend on the conditions existing in each system. The shallower individuals are associated with a depth stratum that represents the boundary between two water masses present in the Canary Islands. The increase in size with depth is related to the presence of submarine volcanic canyons, which constitutes a flow channel of surface organic matter to depth.

Distribution, Nesting Records, and Notes on the Ecology of the White-Throated Caracara (Phalcoboenus albogularis)

ABSTRACT Endemic to Patagonia, the White-throated Caracara (Phalcoboenus albogularis) is one of the least studied caracara species, with several aspects of its ecology, such as breeding biology and diet, largely unexplored. Using citizen science records and opportunistic observations, we obtained data on the breeding biology, nest sites, and diet of the species in Chile and Argentina. Nests were in rocky outcrops and cliffs, and aspects of diet corroborated others’ observations that this species feeds on live prey as well as carrion. The species’ nesting season apparently begins in September and ends in March, with some regional variation. The modal brood size is two, and many nests apparently are used across multiple years. Using citizen science data, we created the first distribution models for the White-throated Caracara, one for the breeding season and one for the winter season. The species predominantly occupies the highland plateaus of western Santa Cruz Province, Argentina, and the Andes Range from around 40° south to southern Tierra del Fuego. The models indicate a mostly consistent distribution without significant latitudinal changes between seasons and, apparently, only a limited transition to lower-elevation areas east of the Andes in winter. In both seasons, this caracara is associated primarily with barren rocky areas and Andean and sub-Andean herbaceous steppe—all open environments—rather than forested areas as has been thought previously. This study provides new knowledge of this regional endemic yet the species remains a poorly known raptor in southern South America. Additional and on-the-ground field research would likely produce benefits when addressing species-related conservation issues.

On features of the life cycle of humpback shrimp Pandalus hypsinotus (Decapoda, Pandalidae) in the Tatar Strait

The study is based on biological analyses of > 80,000 ind. of Pandalus hypsinotus collected in trawl surveys and trap fishery in the Tatar Strait in 2010–2022. Due to the lack of age-recording structures, the size-age structure of shrimp is usually determined by various statistical methods, each of which has some limitations and drawbacks. The modal analysis of size-sex composition dynamics is used in this study, including tracing the growth of strong year-classes. The analysis takes into account the dynamics of major seasonal events such as group molting, spawning, and larval hatching. The reproductive cycle of females is assumed to be 2 years. Based on results of the analysis, the life cycle of humpback shrimp in the Tatar Strait is as follows. After the larvae hatch from eggs in April-May, immature shrimp spend the first year of their life at the depths < 70 m, where they reach the carapace length of 9–15 mm, with a modal size of 11–12 mm. In the second year, they grow to the length of 20–22 mm, on average, then become males and migrate to deeper layer where join the adults. Further growth is described on the data for the strong year-class of 2010: the modal size of males reaches 26–27 mm at age 3 years, 29–30 mm — at age 4, 32–33 mm — at age 5, and 35–36 mm — at age 6. Gender transition of shrimp begins at age 5+, but most males become hermaphroditic at the age 6+. The modal size of intersex hermaphrodites ranges from 37 to 39 mm. At the age of 6 years and 9 months, the intersexes spawn en masse and transform into females. The first larval hatching of new females occurs after 15 months, i.e. at exactly 8 years of age. At least three cycles of spawning (larvae release) are assumed for females, taking into account their polymodal size composition and dynamics of their size increments per molt by age. In assumption of 2-year reproductive cycle, the female stage lasts 6 years. Thus, the total life span for the most of humpback shrimps is estimated to be 12 years (6 years before gender transition and 6 years after). Apparently, a small number of them live 14 years and spawn four times, and some can live up to 16 years and spawn five times.

Using the traditional microscope for mineral grain orientation determination: A prototype image analysis pipeline for optic-axis mapping (POAM).

This paper reports on the development of an open-source image analysis software 'pipeline' dedicated to petrographic microscopy. Using conventional rock thin sections and images from a standard polarising microscope, the pipeline can classify minerals and subgrains into objects and obtain information about optic-axis orientation. Five metamorphic rocks were chosen to test and illustrate the method. Thin sections were imaged using reflected and cross- and plane-polarised transmitted light. Images were taken at different angles of the polariser and analyser (360° with 10° steps), both with and without the full-lambda plate. The resulting image stacks were analysed with a modular pipeline for optic-axis mapping (POAM). POAM consists of external and internal software packages that register, segment, classify, and interpret the visible light spectra using object-based image analysis (OBIAS). The mapped fields-of-view and grain orientation stereonets of interest are presented in the context of whole-slide images. Two innovations are reported. First, we used hierarchical tree region merging on blended multimodal images to classify individual grains of rock-forming minerals into objects. Second, we assembled a new optical mineralogy algorithm chain that identifies the mineral slow axis orientation. The c-axis orientation results were verified with scanning electron microscopy electron backscattered diffraction (SEM-EBSD) data. For quartz (uniaxial) in a granite mylonite the test yielded excellent correspondence of c-axis azimuth and good agreement for inclination. For orthorhombic orthopyroxene in a deformed garnet harzburgite, POAM produced acceptable results for slow axis azimuth. In addition, the method identified slight anisotropy in garnet that would not be appreciated by traditional microscopy. We propose that our method is ideally suited for two commonly performed tasks in mineralogy. First, for mineral grain classification of entire thin sections scans on blended images to provide automated modal abundance estimates and grain size distribution. Second, for prospective fields of view of interest, POAM can rapidly generate slow axis crystal orientation maps from multiangle image stacks on conventionally prepared thin sections for targeting detailed SEM-EBSD studies.

Multi-Scale Analysis of Grain Size in the Component Structures of Sediments Accumulated along the Desert-Loess Transition Zone of the Tengger Desert and Implications for Sources and Aeolian Dust Transportation

Aeolian sediments accumulated along the desert-loess transition zone of the Tengger Desert include heterogeneous textures and complex component structures in their grain-size distributions (GSD). However, the sources of these aeolian sediments have not been resolved due to the lack of large reference GSD sample datasets from adjacent regions that contain various types of sediments; such datasets could be used for fingerprinting based on grain-size properties. This lack of knowledge hinders our understanding of the mechanism of aeolian dust releases in these regions and the effects of forcing of atmospheric circulations on the transportation and accumulation of sediments in this region. In this study, we employed a multi-scale grain-size analysis method, i.e., a combination of the single-sample unmixing (SSU) and the parametric end-member modelling (PEMM) techniques, to resolve the component structures of sediments that had accumulated along the desert-loess transition zone of the Tengger Desert. We have also analyzed the component structures of GSDs of various types of sediments, including mobile and fixed sand dunes, lake sediments, and loess sediments from surrounding regions. Our results demonstrate that the patterns observed in coarser fractions of sediments (i.e., sediments with a mode grain size of >100 μm) from the transition zone match well with the patterns of component structures of several types of sediments from the interior of the Tengger Desert, and the patterns seen in the finer fractions (i.e., fine, medium, and coarse silts with a modal size of <63 μm) were broadly consistent with those of loess sediments from the Qilian Mountains. The deflation/erosion of loess from the Qilian Mountains by wind was the most important mechanism underlying the production of these finer grain-size fractions. The East Asia winter monsoon (EAWM) played a key role in transportation of the aeolian dust from these source regions to the desert-loess transition zone of the desert.

State of the Siberian sturgeon population in the Middle Lena in summer

The purpose: to obtain modern data on the distribution, abundance, size composition and biological state of the sturgeon in the middle reaches of the Lena River.Material: data of scientific accounting survey using bottom drift nets in summer 2022.The results: Siberien sturgeon is dstributed irregularly on a 400‑kilometer stretch of the river from the city of Yakutsk to the Vilyui River, with the highest average density near the Vilyui River mouth 163 ind./km2, while sturgeon densities in the areas of Yakutsk and the Aldan River mouth were 71 and 44 ind./km2 respectively. The highest density of fish with the smallest average size in the area near the Vilyui mouth indirectly indicates the presence of a separate herd in the Vilyui River. The average density of fish over the entire 400‑km area was 93 ind./km2. The sturgeon length to the end of the middle rays (ac) was from 21 to 86 cm; on average 43.4 ± 10.7 cm. The modal size class for the sturgeon in catches in 2022 was 41–50 cm (44% of the total catch). The fish weight ranged from 40 to 3800 g. The average weight of individuals was 0.557. More than 80% of fish from all catches weighed up to 700 g. The weight of fish with a length ac 62–71 cm ranged from 0,400 to 1.415 kg, on average 1.0 kg. There were only 2.5% of commercial individuals in the total harvest. Sexually mature females were noted only near the Aldan mouth, where their share was 11% that may indicate the presence of spawning grounds in its channel. In the sample of fish that underwent a complete biological analysis (one third of the catches), sexually mature males were not observed. Estimated number of sturgeon: in Yakutsk city area — 17000 ind., in the Aldan mouth area — 47000 ind., in the Vilyui mouth area — 55000 ind. The total number of Siberian sturgeon on a 400‑kilometer stretch of the Lena River was at least 120000 ind. The state and structure of sturgeon population corresponds to the average statistical retrospective data.Practical value: the results obtained will improve the efficiency of assessing the distribution and stock of sturgeon in the Lena River.

A gene–culture co-evolutionary perspective on the puzzle of human twinship

Abstract Natural selection should favour litter sizes that optimise trade-offs between brood-size and offspring viability. Across the primate order, the modal litter size is one, suggesting a deep history of selection favouring minimal litters in primates. Humans, however – despite having the longest juvenile period and slowest life-history of all primates – still produce twin births at appreciable rates, even though such births are costly. This presents an evolutionary puzzle. Why is twinning still expressed in humans despite its cost? More puzzling still is the discordance between the principal explanations for human twinning and extant empirical data. Such explanations propose that twinning is regulated by phenotypic plasticity in polyovulation, permitting the production of larger sib sets if and when resources are abundant. However, comparative data suggest that twinning rates are actually highest in poorer economies and lowest in richer, more developed economies. We propose that a historical dynamic of gene–culture co-evolution might better explain this geographic patterning. Our explanation distinguishes geminophilous and geminophobic cultural contexts, as those celebrating twins (e.g. through material support) and those hostile to twins (e.g. through sanction of twin-infanticide). Geminophilous institutions, in particular, may buffer the fitness cost associated with twinning, potentially reducing selection pressures against polyovulation. We conclude by synthesising a mathematical and empirical research programme that might test our ideas.

Terahertz large-area unidirectional surface magnetoplasmon and its applications

Unidirectional surface waves in nonreciprocal plasmonic platforms with nonlocal effects have been a topic of significant interest and some controversy. In this study, we present a scheme to achieve unidirectional surface magnetoplasmons (USMPs) with large modal areas at terahertz frequencies. Such large-area USMPs (LUSMPs) exist in a metal-UENZ (uniaxial-ε\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\varepsilon $$\\end{document}-near-zero)-Si-InSb structure under external magnetic field, where the effect of nonlocality is included. The field of the LUSMP extends almost uniformly in the UENZ layer with a thickness of wavelength scale, thus its modal size can be represented by the UENZ-layer thickness. Due to the modal energy primarily distributed in the thick UENZ layer, the nonlocality-induced leakage of the LUSMP is significantly reduced by an order of magnitude, compared to previous USMP existing at interface between InSb and opaque isotropic medium. Due to their large modal sizes, such LUSMPs can be efficiently excited by terahertz radiations directly from free space. In addition, LUSMPs offer high degree of freedom for manipulating terahertz waves, such as energy squeezing and trapping. Based on LUSMPs, a terahertz free-space isolator is also developed. Our findings have important implications to the development of innovative plasmonic devices in terahertz regime.

Projecting forest cover in Madagascar's protected areas to 2050 and its implications for lemur conservation

AbstractPredicting future conservation needs can help inform conservation management but is subject to uncertainty. We measured deforestation rates during 2015–2017 for 114 protected areas in Madagascar, linked deforestation to the status of protection according to IUCN categories I–VI, used recent deforestation rates to extrapolate forest cover over 2017–2050 and linked the size of forest blocks to the projected persistence of lemur subpopulations. In the six IUCN categories for protected areas in Madagascar the median size of forest blocks is 9–37 km2 and median annual deforestation rates range from 0.02% in the single IUCN category III site to 0.19% in category II and 1.95% in category VI sites. In 2017, 40% of all forest blocks within protected areas were < 10 km2, and this is projected to increase to 45% in 2050. Apart from these small forest fragments, the modal site of forest blocks was 160–320 km2 in 2017, and this is projected to decrease to 80–160 km2 in 2050. The range of > 50% of all lemur species exclusively contains forest blocks of < 10 km2. The modal size of forest blocks > 10 km2 is predicted to remain at 120 km2 until 2050. Although uncertainty remains, these analyses provide hope that forest blocks within the protected areas of Madagascar will remain large enough to maintain lemur subpopulations for most species until 2050. This should allow sufficient time for the implementation of effective conservation measures.

Cytogenetic studies in the Andropogon gayanus-Andropogon tectorum Complex in Southwestern Nigeria

The studies were carried on accessions of the Andropogon gayanus-Andropogon tectorum complex (Poaceae) in southwestern Nigeria to determine the chromosome numbers and meiotic dynamics in the species. This involves meiotic chromosome and pollen studies using standard procedures. Studies on the morphology and meiotic behaviour of collections of A. gayanus (2n = 40) and A. tectorum (2n = 20, 40) have been made. The cytogenetic studies show that the chromosome configuration of A. gayanus is a tetraploid (2n = 40) on a basic chromosome number of 10. A. tectorum occurs as a regular diploid on a chromosome number of 2n = 20 and it is the only species found in Ekiti State. Accession “Kiwani” was found to be a polyploid. A. tectorum with a chromosome number of 2n = 40. This study has also established the stability of the genome of the Andropogon complex. In spite of the occurrence of univalent and multiple associations, meiosis ensures a high percentage of pollen grains. The pollens of accession “Kiwani” (> 35 µm) were generally larger than those of other accessions while the other accessions of both A. gayanus and A. tectorum have modal pollen sizes less than 35 µm, although the A. tectorum accessions were generally smaller. The study concluded that the occurrence of the tetraploid (2n = 40 in accession AT10, “Kiwani” can be attributed to apomixis occurring in a lonely plant.

Comprehensive Analysis of Physicochemical, Functional, Thermal, and Morphological Properties of Microgreens from Different Botanical Sources.

Due to the significant increase in global pollution and a corresponding decrease in agricultural land, there is a growing demand for sustainable modes of modern agriculture that can provide nutritious food. In this regard, microgreens are an excellent option as they are loaded with nutrients and can be grown in controlled environments using various vertical farming approaches. Microgreens are salad crops that mature within 15-20 days, and they have tender leaves with an abundant nutritive value. Therefore, this study aims to explore the physicochemical, techno-functional, functional, thermal, and morphological characteristics of four botanical varieties of microgreens, including carrot (Daucus carota), spinach (Spinacia oleracea), bathua (Chenopodium album), and Bengal gram (Cicer arietinum), which are known for their exceptional nutritional benefits. Among the four botanical varieties of microgreens studied, bathua microgreens demonstrated the highest protein content (3.40%), water holding capacity (1.58 g/g), emulsion activity (56.37%), and emulsion stability (53.72%). On the other hand, Bengal gram microgreens had the highest total phenolic content (32.2 mg GAE/g), total flavonoid content (7.57 mg QE/100 g), and DPPH activity (90.60%). Fourier transform infrared spectroscopy analysis of all microgreens revealed the presence of alkanes, amines, and alcohols. Moreover, X-ray diffraction analysis indicated low crystallinity and high amorphousness in the microgreens. Particle size analysis showed that the median, modal, and mean sizes of the microgreens ranged from 110.327 to 952.393, 331.06 to 857.773, and 97.567 to 406.037 μm, respectively. As per the observations of the results, specific types of microgreens can be utilized as an ingredient in food processing industry, including bakery, confectionery, and more, making them a promising nutritive additive for consumers. This study sheds light on various food-based analytical parameters and offers a foundation for future research to fully harness the potential of microgreens as a novel and sustainable food source, benefiting both the industry and consumers alike.

Potential to produce brown mussel integrated to a net-cage fish farm in a Mediterranean bay

In this study, we investigated the potential exploitation of the brown mussel Perna perna (Linnaeus, 1758) in an aquaculture farm (Monastir Bay, Mediterranean Sea, Tunisia). The quality of seawater as well as performance indicators such as Condition Index, length, weight, growth and frequency distribution of the mussel were determined over an annual cycle; from July 2017 to August 2018. Interestingly, P. perna has an extended sexual cycle during the year with two main spawning periods, the first in spring and the second in autumn, when suspended matter and Chlorophyll a were at their maximum concentrations in seawater. Spat mussels and young mussels showed significant growth rates from 1 July 2017 to 31 October 2017. Adult mussels exhibited negative allometric growth and a modal size of 41 to 50 mm. Results showed that several potentially toxic microalgae species developed at low densities in this marine zone. By using Solid Phase Adsorption Toxins Tracker (SPATT); lipophilic toxins including Okadaic acid and yessotoxins were detected at low levels in seawater and may be involved in the positive LSTs (lipophilic shellfish toxins) mouse bioassays in P. perna during the autumn. No other toxins such as paralytic shellfish toxins or amnesic shellfish toxins nor pathogenic bacteria or viruses were detected in P. perna. Altogether, our results suggest that finfish farms in Monastir Bay could be suitable sites for farming P. perna.

STUDY OF THE RHEOLOGICAL AND PHYSICOCHEMICAL PROPERTIES OF FRUCTAN FRACTIONS OF Agave tequilana cv. cenizo

The physico-mechanical properties of fructan fractions in different agave species without Tequila Denomination of Origin (DOT) need to be studied to identify and expand industrial applications. The rheological and physicochemical characterization of three fractions of Agave tequilana cv. cenizo fructans without DOT, with different degree of polymerization (DP) was carried out to propose their use as an additive in the food industry. Fractions were obtained by apparent DP enrichment (DPa) by stepwise ultradiafiltration with 10, 5 and 1 kilodalton (kDa) membranes and classified on the basis of the enriched fraction evidenced by HPLC profiling with amperometric detector. The ultradiafiltrate of the membrane with 10 kDa, called High Degree of Polymerization (HDP), showed enrichment of fructans with high DPa ≥ 30, the one with 5 kDa called Intermediate Degree of Polymerization (IDP), presents enrichment in DPa between 10 to 30, these fractions dried by spray, showed a modal particle size distribution (D [4,3] < 20 µm). In the ultradiafiltrate of the 1 kDa membrane, called Low Polymerization Grade (LDP), fructo-oligosaccharides (FOS) and fructans with maximum DPa of 15 were enriched; this sample was concentrated to 72 °Brix. The glass transition (Tg) showed a DPa-dependent increase (LDP = 152.17 °C, IDP = 216.12 °C and HDP = 227.5 °C). Viscosity was dependent on the degree of polymerization, exhibiting thermo-mechanically stable flow behavior. The reconstituted powders exhibited Newtonian and flow-stable behavior in a concentration range of 2-50 %, temperature of 5-45 °C and pH of 2-9. The macro and micro structural properties identified in the respective fractions of agave fructans, diversify possible applications with potential interest as encapsulating material, stabilizer and prebiotic sweetener, among others that agave fructans have in the food and nutraceutical industry.

Seasonal ice-covered lake surface likely caused the spatial heterogeneity of aeolian sediment grain-size in the source region of Yellow River, northeastern Tibetan Plateau, China

The area of lakes in Tibetan Plateau (TP) is 36522 km2, accounting for nearly half (49.1%) of the total lake surface area in China, and the lakes in TP are seasonally ice-covered for 4–5 months per year. In such a high-cold Third Pole with extensive lakes, how does aeolian sediment transport on ice cover and to what extent can seasonal ice-covered lake cause sediment redistribution by providing pathways for sediment migration is rarely studied. The source region of Yellow River (SRYR) is located in the northeastern TP with an altitude above 4000 m, is home to large area of seasonal frozen lakes. Nine sections of aeolian sediments were collected from SRYR for grain-size study. The end-member modeling analysis (EMMA) provides a greater chance of resolving aeolian sediment sources since it can quantitatively separate the particle size components of various sedimentary dynamic processes and sources in the sediment. The result shows great spatial difference of the mean grain sizes (mainly varying between 70 and 230 μm). Parametric EMMA is applied to study the provenance tracing of aeolian sediment, combining with remote sensing images and wind data. Aeolian processes were analyzed by separating and extracting the grain size end-members of nine sections, and four statistical end-members (modal grain size is 8.9, 79.5, 141.6, and 251.8 μm, respectively) were classified from the grain size distribution. It shows that the sedimentary sequences in sections 7 and 8 have high EM2 and EM3 fractions and very low EM4 content at all depths. Based on comprehensive analysis of aeolian sediment grain-size, phenology of ice lake, wind regime and remote sensing images, it revealed that the fine aeolian sediments (sections 7 and 8) on the downwind shore of Ngoring Lake likely transported from the upwind shore, which were blown across the ice-covered lake surface by prevailing west wind in winter and spring, but the coarse sediments could be trapped by ice cracks. Therefore, it’s concluded that the aeolian sediment transport on seasonal ice-covered lakes may lead to the spatial heterogeneity of aeolian sediment grain-size in the SRYR.