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Day by day, humans and animals are infected with life-threatening and deadly diseases due to mosquito bites. Current methods used to fight these diseases are not fully viable and unsafe for humans and animals. Controlling the germ-carrying mosquitoes requires the immediate transfer of a conceptual paradigm. This experiment suggested a safe mosquito control mechanism with fluorescence iron-oxide core carbon-coated (f-Fe3O4@C) nontoxic nanoparticles used as an active agent. As the concept of experiment, we chose mosquitoes of Anopheles, Aedes, and Culex genera because they are found worldwide and infect pathogens. The progression of the life cycle of mosquitoes was observed and imaging under the treated known concentration of f-Fe3O4@C nanoparticles. Resulted that a minimum 3 mg/L and above concentration of f-Fe3O4@C nanoparticles in breeding water these group of larvae can’t attend their adulthood and ultimately died under prolong stay in the larval stage. In this case, though the species can be studied for a sustained time the originality of the wild species is lost.

A straightforward synthetic strategy is developed in this study to synthesize highly fluorescent red phosphorus on nitrogen-doped reduced graphene oxide (f-RP@N-rGO) nanosheets in an aqueous medium; this is used as a novel detection platform for the label-free real-time sensing of nucleic acids with low background noise and a high signal-to-noise ratio.

The remarkable mechanical, electrical, and thermal capabilities of monolayer graphene make it a wonder substance. As the number of layers in graphene flakes increases to few-layer graphene (number of layers ≤ 5) and multi-layer graphene (number of layers ≤ 10), its properties are affected. In order to obtain the necessary qualities, it is crucial to manage the number of layers in the graphene flake. Therefore, in the current review, we discuss the various processes for producing mono- and few-/multi-layer graphene. The impact of mono-/few-/multi-layer graphene is then assessed with regard to its qualities (including mechanical, thermal, and optical properties). Graphene possesses unique electrical features, such as good carrier mobility, typical ambipolar behaviour, and a unique energy band structure, which might be employed in field effect transistors (FETs) and utilized in radio frequency (RF) circuits, sensors, memory, and other applications. In this review, we cover graphene’s integration into devices for biomolecule detection as well as biomedical applications. The advantages of using graphene in each situation are explored, and samples of the most cutting-edge solutions for biomedical devices and other applications are documented and reviewed.

Soil degradation is a worsening global phenomenon driven by socio‐economic pressures, poor land management practices and climate change. A deterioration of soil structure at timescales ranging from seconds to centuries is implicated in most forms of soil degradation including the depletion of nutrients and organic matter, erosion and compaction. New soil–crop models that could account for soil structure dynamics at decadal to centennial timescales would provide insights into the relative importance of the various underlying physical (e.g. tillage, traffic compaction, swell/shrink and freeze/thaw) and biological (e.g. plant root growth, soil microbial and faunal activity) mechanisms, their impacts on soil hydrological processes and plant growth, as well as the relevant timescales of soil degradation and recovery. However, the development of such a model remains a challenge due to the enormous complexity of the interactions in the soil–plant system. In this paper, we focus on the impacts of biological processes on soil structure dynamics, especially the growth of plant roots and the activity of soil fauna and microorganisms. We first define what we mean by soil structure and then review current understanding of how these biological agents impact soil structure. We then develop a new framework for modelling soil structure dynamics, which is designed to be compatible with soil–crop models that operate at the soil profile scale and for long temporal scales (i.e. decades, centuries). We illustrate the modelling concept with a case study on the role of root growth and earthworm bioturbation in restoring the structure of a severely compacted soil., This photograph, depicting ant bioturbation, was taken at the compaction recovery experiment at Agroscope, Zurich, Switzerland. Together with other biological processes, faunal bioturbation profoundly influences soil structure and thus soil physical and hydraulic properties, hydrological processes and plant growth. The parsimonious model concept developed in this paper, which is designed to be compatible with profile‐scale soil–crop models, allows simulation of the effects of biological agents (e.g. plant roots and soil‐living organisms) on soil structure dynamics.

The soil structure near the surface of agricultural soils changes with seasons mainly by land management together with climatic and biological factors. Quantitative analysis of post-tillage changes in soil structure and related hydraulic properties are necessary for evaluating and improving models of soil hydrological and transport processes. The objectives of this study were to quantify changes in soil seedbed structure induced by rainfall and drainage and to estimate the effects of soil texture and SOC on these changes. We collected samples from the harrowed layer of twenty-six fine to coarse textured Swedish mineral soils. Air-dried soil was placed in cylinders (5 cm high, diameter 5 cm) and exposed to simulated rainfall (5 mm h−1 for 4 h) and drainage (-50 cm pressure potential) cycles in the laboratory. We used X-ray tomography to quantify changes in pore networks in a thin surface layer and in the whole cylinder. Infiltration rates at -5 cm pressure potential were measured using a mini disc tension infiltrometer on replicate air-dried samples and on the samples included in the consolidation experiments at the final state. Total imaged specific pore volumes generally decreased from initial to final state and pore size distributions were shifted towards larger proportions of below image resolution pores (< 80 μm). There was a strong positive correlation between clay content and changes in the specific volume of pores

Triclosan (TCS) is a widely used chemical in personal care and household products as an antimicrobial agent but some studies have reported it as being estrogenic. We investigated the influence of TCS on the male reproductive system of postnatal pups. Lactating mother rats (Rattus norvegicus) were given daily doses of 0 mg, 3 mg, and 5 mg/kg/day from the day of delivery until 28 days, equivalent to their natural breastfeeding duration. At 28 days, the male pups of all three groups were sacrificed and their biochemical parameters evaluated. TCS-treated pups had decreased mRNA levels for 3&beta, hydro-hydroxysteroid dehydrogenases (3&beta, HSD), OCT3/4, and androgen receptor (AR) (p &lt, 0.05). The higher dose (5 mg/kg/day) male pups exhibited more significantly affected germ cell maturation and decreased body weight. In summary, TCS-treated lactating mothers passed the deleterious effects to their untreated male pups as exhibited by reduced androgens synthesis and subsequently decreased sperm count.

The soil water retention curve (SWRC) is a unique relationship between water content and soil water potential. SWRC in near saturation gives the dimension of soil macroporosity which plays an important role in water translocation into soil. Thus, the accurate measurement of SWRC is crucial. The aim of this study is to compare SWRC obtained through two different methods: X-ray computed microtomography (X-ray CT) and evaporation method by HYPROP device. Three different depths (0–10, 25–30 and 45–60 cm) are considered for soil sampling. The results showed significant differences in SWRC between the techniques. The SWRC from X-ray CT showed more volumetric water content at 25–30 cm (0.044) and 45–60 cm (0.024) than evaporation at saturation (0 kPa) in cases where the macroporosity was higher. Macropores may have connections with neighbouring pores of smaller sizes. Hence we assume that these pores can be observed through X-ray CT but cannot be evaluated by evaporation. As macropores with narrow opening do not evaporate at very low tension. These pores therefore got empty at relatively higher tension. Consequently, SWRC near saturation appeared rather flatter with the evaporation method where the X-ray CT presented deviation. Accordingly, interpretation of macro pores from SWRC through evaporation method would give comparatively smaller volume of macropores than they really are. Pore morphology and other hydraulic functions of soil, for example, mean connection surface of pores, hydraulic conductivity, and the efficiency of water conducting macropores also support the X-ray CT findings.

Hydrothermal treatment of a mixture of ethylene diamine, phosphoric acid and citric acid under ambient pressure generates fluorescent carbon dots that are co-doped with phosphorus and nitrogen. These have features such as (a) both green fluorescence (peaking at 430 nm; 30% quantum yield) and red fluorescence (peaking at 500 nm, quantum yield 78%), (b) wavelength-dependent emission peaks, and (c) insensitivity to changes of pH values, dot concentration and ionic strength. The C-dots are useful for both fluorescent (FL) and photoacoustic (PA) imaging of living tissue. PA imaging warrants better spatial resolution and allows deeper tissues to be imaged compared to most optical imaging techniques. It is essential to assign a photoacoustic contrast agent as most of the diseases do not show a natural photoacoustic contrast in their early stage. The dually emitting C-dots are shown to be a useful contrast agent for PA and FL imaging of mice tumors. Intravenous administration of the C-dots resulted in strong signals in both PA and FL imaging.

A modified method is described for the preparation of amino-functionalized covalent organic framework nanosheets (COF-NSs). These consist of hexagonal layered sheets and were prepared from commercially available starting materials (p-phenylenediamine and benzene-1,3,5-tricarboxaldehyde). The interlayer stacking interactions between the ultra-thin COF-NSs became weak because the π stacking is destroyed by sonication. This result in the exfoliation of COF-NSs. As an application, the COF-NSs used for sensitive and selective fluorometric determination of DNA. To reach this goal, H1 and H2 hairpin-like DNA probes were chosen; H1 used Texas Red-labeled dye as a fluorescent probe. The addition of the COF-NSs, the hairpin probes was adsorbed onto the porous surface of the COFNSs. The π stacking and hydrogen-bond interactions between COFNSs and nucleic acid quench the fluorescence of the Texas red-labeled probe. The target DNA enables the recovery of the quenched fluorescence of the Texas red-labelled probe by triggering an inter-chain hybridization within hairpin probes. This results in a weaker interaction of double-stranded DNA (dsDNA) with the COFNSs. Consequently, the dsDNA detaches from the COFNSs, thereby recovering the dye's fluorescence (excitation/emission maxima at 590/612 nm) with increasing target DNA concentration. The findings were applied to design a method for the determination of DNA that has a 2 pM detection limit. This is significantly lower than the limit of detection reported previously for 2D nanomaterial-based fluorometric DNA assays. Graphical abstractSchematic representation of 2D-covalent organic framework nanosheets (COF-NSs) probe act as a quencher allowing the highly sensitive and selective fluorescence turn-on detection for biomolecules. Here the H1 H2 are hairpin DNAs. H1 is associated with the fluorescent tag (red circle), while the "fluorescence off" state it denoted as a black circle.

The soil structure near the surface of agricultural soils changes with season mainly by land management together with climatic and biological factors. Quantitative analysis of post-tillage changes in soil structure and related hydraulic properties are necessary for evaluating and improving models of soil hydrological and transport processes. The objectives of this study were to quantify changes in soil seedbed structure induced by rainfall and drainage and to estimate the eff ;ects of soil texture and SOC on these changes. We collected samples from the harrowed layer of twenty-six fine to coarse textured Swedish mineral soils. Air-dried soil was placed in cylinders (5 cm high, diameter 5 cm) and exposed to simulated rainfall (5 mm h−1 for 4 h) and drainage (−50 cm pressure potential) cycles in the laboratory. We used X-ray tomography to quantify changes in pore networks in a thin surface layer and in the whole cylinder. Infiltration rates at -5 cm pressure potential were measured using a mini disc tension infiltrometer on replicate air-dried samples and on the samples included in the consolidation experiments at the final state. Total imaged specific pore volumes generally decreased from initial to final state and pore size distributions were shifted towards larger proportions of below image resolution pores (

Highly fluorescent, broad range pH and ionic-stable N-doped carbon quantum dots (N-CQDs) were successfully synthesized and their chemical structure and fluorescence mechanism were characterized. Mono-dispersed N-CQDs averaging 4.5 nm in diameter were achieved in a quantum yield (QY) of 74.16%. These N-CQDs showed great potential in biomedical and optical imaging applications both in vivo and in vitro. Biodistribution, retention, toxicity, and pharmacokinetics profiles are mandatory in their potential clinical applications. Herein, the biodistribution, clearance, and toxicity of our invariable N-CQDs species were systematically investigated over 7 days in mice. Most of the N-CQDs were cleared at 6 days post-injection without any accumulation in any vital organs or tissues. Moreover, the high fluorescence N-CQDs were demonstrated to be effective as printing inks for multicolour patterns. This study suggests that N-CQDs may be an attractive alternative to metal quantum dots for secure biomedical and other industrial applications.

This study was conducted in spring 2011 in a long-term field experiment with the objective of assessing the effect of shallow tillage (ST) and mouldboard ploughing (MP) on important soil physical properties and crop performance. Undisturbed soil samples were taken before sowing from depths of 15–20, 25–30 and 35–40 cm for the determination of saturated hydraulic conductivity (Ks), bulk density (Bd), and water retention capacity in laboratory conditions. Penetrometer resistance (PR) was measured in the field after 1 month of sowing. Plant density of barley (Hordeum vulgare) was also counted after 1 month of sowing. Field water content was significantly higher for MP than ST at 15–20 cm (MP = 27%, ST = 22.5%) and 25–30 cm depth (MP = 29.3%, ST = 24.8). Water retention at 1 m suction was also significantly higher in the treatment with MP at the depth of 25–30 cm (31%) than in the ST treatment (27.7%). Significantly higher Ks value was found for ST at depths of 15–20 (13.09 cm h−1) and 25–30 cm (5.10 ...

Amino acid (AA) levels in plasma and body growth were determined in rats (n20) fed diets with different soya bean meal levels. Free AA in plasma was determined by reversed-phase high-pressure liquid chromatography. We have used four levels of protein diets like 8%, 15%, 23% and 35% in this trial. Rats which were fed the low-protein (8%) diet with low percentage of soya bean meal were found to be growth-retarded. The body weight gain of high protein group (35%) was lower than that of the 23% groups. In the rats fed with the low-soya bean meal diet, some nonessential AA (NEAA) in plasma like asparagine, aspartic acid, cysteine, glutamic acid and serine increased, whereas the essential AA (EAA), with the exception of arginine, methionine and valine decreased. Here, plasma EAA-to-NEAA ratios were not correlated to growth and experimental diet. We hypothesize that AA metabolism is associated to changes in growth in rats on different protein intake. This study has showed the sensitivity of body mass gain, feed intake, feed conversion rate of rats to four levels of protein in the diet under controlled experimental conditions.

This work demonstrated a fluorescence measurement method for rapid detection of bacteria and their counting by using water-soluble carbon quantum dots (CQDs) as a fluorescence marker while sewage water bacteria were detection target bacteria. Highly luminescent water-soluble CQDs were prepared by carbonizing waste part of rice straw materials in a furnace under in-sufficient air flow. Bacteria in a LB media with < 100 nm of water soluble CQDs were cultured for 30-40 minutes. The multi colored bacterial cell images were obtained by using fluorescence microscopy. Our results showed that CQDs prepared in water phase were highly luminescent, stable, and successfully conjugated with bacterial cell membrane only. Also we could count the total number of bacteria within a shortest time from any sample of environment.

Soil hydrology research requires the accurate measurement of soil water content. Recently, less expensive capacitance sensors (CS) have become popular for the measurement of soil moisture across soil profiles, but these sensors need to be calibrated for precise results. The purpose of the present study was to determine the effect of clay content and bulk density (ρb) on the calibration of CS. Two different CS (10HS and 5TM) were considered for the study. Clay content and ρb of the soils were determined from two different sites and from three different depths (0–5, 25–30 and 50–60 cm) of an experimental field in Gembloux, Belgium. Custom calibration (CC) equations were developed using packed soil columns following the same ρb at sequential volumetric water content (θ) levels. The factory-supplied calibration (FSC) showed an overestimation of θ (0.04–0.07 m3 m–3) with the 10HS sensor, and an underestimation of θ (0.06–0.077 m3 m–3) with the 5TM sensor for the entire calibration range. The variance in raw sensor outputs for different ρb and clay content of soil depths was not highly significant because the soil had limited range of variability in ρb and clay content. However, the CC is recommended in parallel with FSC for the precise measurement of soil moisture with CS.