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1.
Seaweeds are broadly distributed and represent an important source of secondary metabolites (e.g., halogenated compounds, polyphenols) eliciting various pharmacological activities and playing a relevant ecological role in the anti-epibiosis. Importantly, host (as known as basibiont such as algae)–microbe (as known as epibiont such as bacteria) interaction (as known as halobiont) is a driving force for coevolution in the marine environment. Nevertheless, halobionts may be fundamental (harmless) or detrimental (harmful) to the functioning of the host. In addition to biotic factors, abiotic factors (e.g., pH, salinity, temperature, nutrients) regulate halobionts. Spatiotemporal and functional exploration of such dynamic interactions appear crucial. Indeed, environmental stress in a constantly changing ocean may disturb complex mutualistic relations, through mechanisms involving host chemical defense strategies (e.g., secretion of secondary metabolites and antifouling chemicals by quorum sensing). It is worth mentioning that many of bioactive compounds, such as terpenoids, previously attributed to macroalgae are in fact produced or metabolized by their associated microorganisms (e.g., bacteria, fungi, viruses, parasites). Eventually, recent metagenomics analyses suggest that microbes may have acquired seaweed associated genes because of increased seaweed in diets. This article retrospectively reviews pertinent studies on the spatiotemporal and functional seaweed-associated microbiota interactions which can lead to the production of bioactive compounds with high antifouling, theranostic, and biotechnological potential.  相似文献   
2.
This study examined the three-dimensional (3D) microarchitecture of regions of the equine third metacarpal bone (McIII) commonly involved in distal condylar fractures. Limbs were obtained from Thoroughbred horses (neonates to age 24 years) destroyed for inoperable fractures and a variety of other conditions. Beams, blocks and sections were cut in the principal axes, some embedded in PMMA and others examined unembedded. Several methods were used to study the 3D structure, including conventional and confocal optical microscopy, scanning electron microscopy (SEM) and radiography. The mineralised articular cartilage tends to cleave in the sagittal plane. Proximal to the subchondral bone, the main trabeculae are robust plates running in the sagittal direction with less significant mediolateral connections. Small blood vessel canals lie inside the sagittal plates. This structure gives maximum strength and protection in the sagittal plane in which the bone rotates, but offers minimal resistance to fracture propagation in this plane. The anatomical course of the common distal condylar fractures of the third metacarpal bones can be explained by underlying anisotropic structural features of the mineralised tissues.  相似文献   
3.
Mulching of Sclerotium oryzae infested soil (moist or dry) with polyethylene sheets during hot summer days of May and June increased the soil temperature at 5 cm from 36°C (unmulched) to 48°C (wet) and from 44 to 52°C (dry) and at 20cm from 32 to 38°C (wet) and from 35 to 39°C (dry). In artificially-infested soil, the sclerotia were not eradicated but 95–100% loss in viability was observed at 5 cm by a mulch treatment for 1 week and at 20 cm by mulching for 8 weeks. Mulching effects were not influenced by moisture content of soil or by amendments with lucerne or wheat straw. Mulching of naturally-infested soil at a second site did not eradicate S. oryzae but reduced sclerotial viability by 93%.  相似文献   
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5.
Prostate cancer (PCa) is the leading cause of cancer death in men, and its treatment is commonly associated with severe adverse effects. Thus, new treatment modalities are required. In this context, natural compounds have been widely explored for their anti-PCa properties. Aquatic organisms contain numerous potential medications. Anticancer peptides are less toxic to normal cells and provide an efficacious treatment approach via multiple mechanisms, including altered cell viability, apoptosis, cell migration/invasion, suppression of angiogenesis and microtubule balance disturbances. This review sheds light on marine peptides as efficacious and safe therapeutic agents for PCa.  相似文献   
6.
The present work was conducted to study the comparative efficacy of two anti-protozoan (babesicidal) drugs on the recovery and health of horses. A total of 80 horses, showing typical clinical symptoms of the disease, were selected for this study; the presence of babesiosis was confirmed through blood smear examination. These animals were divided into two groups i.e. A and B. Horses of Group A, were treated with diminazene diaceturate, while horses of Group B were treated with diminazene aceturate. Efficacy of the drugs was determined by the reversal of clinical signs and a negative blood smear examination. The efficacy of diminazene diaceturate was demonstrated to be 80% while diminazene aceturate was found to have 90% efficacy against babesiosis.  相似文献   
7.
This study was carried out to investigate the growth performance, carcass yield and meat quality of large-type Korean native ducks (KND). A total of 420 day-old ducklings were divided into four treatments (seven replicates/treatment, 15 birds/replicate) by strains (A and B) and gender (male and female) in a 2 × 2 factorial arrangement under complete randomized design. The body weight (BW) of female KND was higher at week 2 and for male it was higher in week 8 (P 〈 0.05). BW gain, feed intake and feed conversion ratio of male KND were higher than those of female KND (P 〈 0.05) during week 0 to week 8. The carcass yield of both strains increased from 6 weeks to 8 weeks (P 〈 0.05). The breast meat ratio was the highest at week 8 whereas the leg meat ratio was the highest at 6 weeks of age in both strains (P 〈 0.01). Lightness (L*), yellowness (b*) and juiciness of meat were the highest at 6 weeks (P 〈 0.05). Moisture, ash and fat contents of meat were the highest at 7 weeks (P 〈 0.05) and protein content was the highest at 8 weeks (P 〈 0.01). These results may provide the basic data on growth performance and meat quality of large-type KND, which can be used for genetic improvements and rearing at commercial scale.  相似文献   
8.
Stabilizing the carbon dioxide-induced component of climate change is an energy problem. Establishment of a course toward such stabilization will require the development within the coming decades of primary energy sources that do not emit carbon dioxide to the atmosphere, in addition to efforts to reduce end-use energy demand. Mid-century primary power requirements that are free of carbon dioxide emissions could be several times what we now derive from fossil fuels (approximately 10(13) watts), even with improvements in energy efficiency. Here we survey possible future energy sources, evaluated for their capability to supply massive amounts of carbon emission-free energy and for their potential for large-scale commercialization. Possible candidates for primary energy sources include terrestrial solar and wind energy, solar power satellites, biomass, nuclear fission, nuclear fusion, fission-fusion hybrids, and fossil fuels from which carbon has been sequestered. Non-primary power technologies that could contribute to climate stabilization include efficiency improvements, hydrogen production, storage and transport, superconducting global electric grids, and geoengineering. All of these approaches currently have severe deficiencies that limit their ability to stabilize global climate. We conclude that a broad range of intensive research and development is urgently needed to produce technological options that can allow both climate stabilization and economic development.  相似文献   
9.
ABSTRACT

A greenhouse experiment was conducted to evaluate the effects of wheat straw and its biochar on tomato seedling growth and soil physicochemical properties under different moisture levels. Treatments included control (no amendments, CK), three biochar amendments (B1: 1%, B2: 3% and B3: 6% w/w) and three straw amendments (S1: 1%, S2: 3% and S3: 6% w/w), under two moisture levels (M1: 40% water holding capacity (WHC) and M2: 70% WHC). The straw and biochar had contrasting effects on soil physiochemical properties and physiology of tomato seedlings. The B1 treatment significantly increased the soil urease activity (15%) and decreased the activity of dehydrogenase and β glucosidase enzymes (67% and 56%), as compared to the S1 treatment, especially for the high moisture condition. Biochar significantly improved shoot and root dry weights, biomass and altered chlorophyll contents. Plant antioxidants, superoxide dismutase (SOD), Peroxidase (POD) activities and malondialdehyde (MDA) were significantly decreased in biochar treatments, however, an increasing trend was observed for straw treatments. The current findings suggest that application of high amount of biochar (6%) or low amount of straw (1%) would be a reasonable management practice in semi-arid regions to improve soil physiochemical properties and the physiology of tomato seedlings.  相似文献   
10.
Farmers in Pakistan continue to produce maize under various types of risks and adopt several strategies to manage those risks. This study is the first attempt to investigate the factors affecting the concurrent adoption of off-farm income diversification and agricultural credit which the farmers use to manage the risk to maize production. We apply bivariate and multinomial probit approaches to the primary data collected from four districts of Punjab Province in Pakistan. The results show that strong correlations exist between the off-farm diversification and agricultural credit which indicates that the use of one risk management strategy leads to another. The findings demonstrate that education, livestock number, maize farming experience, perceptions of biological risks and risk-averse nature of the growers significantly encourage the adoption of diversification as a risk management tool while farm size inversely affects the adoption of diversification. Similarly, in the adoption equation of credit, maize farming experience, farm size, perceptions of price and biological risks and risk attitude of farmers significantly enhance the chances of adopting agricultural credit to manage farm risks. These findings are important for the relevant stakeholders who seek to offer carefully designed risk minimizing options to the maize farmers.  相似文献   
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