Characterisation of river reaches: The influence of rock type

The characterisation of geomorphological, hydrological and ecological properties of river systems represents a popular and important research direction in fluvial studies, particularly with regards to contemporary international environmental legislation. Recent research has also drawn attention to the unique ecological value and high level of environmental threat associated with groundwater-fed catchments, emphasising the importance of underlying rock type in the development of river typologies. A standardised field method for assessing physical river habitat quality known as River Habitat Survey (RHS) has been developed in the UK and provides an extensive data set of surveyed river reaches. This paper uses information from the RHS database to explore the influence of rock type on reach-scale sedimentological and vegetation characteristics. A range of reach-scale indices are derived from the RHS database for analysis, supported by landscape variables which provide detail on the catchment context. River reaches were then classified into broad lithological groups which reveal statistically significant differences along two key gradients in environmental conditions: an energy gradient associated with stream power and sediment calibre which is inversely related to in-channel vegetation roughness, and a riparian vegetation gradient that also reflects the inverse relationship between instream and riparian vegetation cover. The results emphasise the differences in reach-scale geomorphological and ecological structure between groundwater-fed and surface water-fed catchments, supporting the inclusion of underlying reach lithology in the development of river typologies.     

Antioxidant,ACE-Inhibitory,and Antimicrobial Activities of Peptide Fractions Obtained From Dried Giant Squid Tunics

ABSTRACT

Squid tunics were divided in two batches: freeze-dried and air-dried. Dried squid tunics were directly hydrolyzed with pepsin, Alcalase, and Esperase. Freeze-dried tunics showed better aptitude for hydrolysis than air-dried tunics. Pepsin showed the lowest efficiency in protein breakdown and gave hydrolysates with low antioxidant activity, whereas Alcalase and Esperase peptide fractions showed strong radical scavenging ability, ACE-inhibitory activity, and noticeable antimicrobial properties. B. cereus, B. coagulans, and D. hansenii were found to be the most sensitive bacteria. Dried squid tunics proved to be an alternative to a previously extracted gelatin for obtaining bioactive peptides.     

桃果实水孔蛋白cDNA的分离

使用逆转录聚合酶链失反应(RT-PCR)技术从桃果实的果皮组织中分离出来2个编码水孔蛋白部分cDNA克隆.比较结果表明,其推导的氨基酸序列与从其他一些植物体中分离出来的液泡膜内在蛋白有很高的同源性.数量PCR分析表明,编码水孔蛋白基因pWCl在果实发育早期表达,而pWC2在果实发育期间全过程均有表达.     

Impacts caused by the addition of wine vinasse on some chemical and mineralogical properties of a Luvisol and a Vertisol in La Mancha (Central Spain)

Background, aim, and scope  Using wastewaters from wine production that are often discharged directly into soil, with previous treatment, we carried out an experiment to identify the impact over time, specifically to identify the benefits and risks of its application. Materials and methods  Experiments were carried out using approximately 200 g of samples of agricultural soils which were amended with increased amounts of vinasse: 1–5–10–20–40–70 ml. The doses used were not arbitrary but similar to the usual one amended. Soil electric conductivity was determined in distilled water with a glass electrode (soil to H₂O ratio 1:5). Clay identification of soil samples are by X-ray diffraction. Results  The pH decreased slightly and salinity increased, possibly leading to changes in crop productivity. The increase in salinity reflects the concentration of dissolved salts in the vinasse. Significant changes were observed in the clay minerals after amendment with the vinasse. Conclusions  Our study indicates that, under experimental incubation, the application of increasing doses of wine vinasse for increasingly long periods can affect certain chemical properties. The results show that application of winery wastewaters to soil results in significant increases of electrical conductivity, reaching levels that can be detrimental to crop growth. The decrease in pH values is somehow beneficial, and finally there is a small increase in the chemical weathering of clay minerals     

The sand seas of Titan: Cassini RADAR observations of longitudinal dunes

The most recent Cassini RADAR images of Titan show widespread regions (up to 1500 kilometers by 200 kilometers) of near-parallel radar-dark linear features that appear to be seas of longitudinal dunes similar to those seen in the Namib desert on Earth. The Ku-band (2.17-centimeter wavelength) images show approximately 100-meter ridges consistent with duneforms and reveal flow interactions with underlying hills. The distribution and orientation of the dunes support a model of fluctuating surface winds of approximately 0.5 meter per second resulting from the combination of an eastward flow with a variable tidal wind. The existence of dunes also requires geological processes that create sand-sized (100- to 300-micrometer) particulates and a lack of persistent equatorial surface liquids to act as sand traps.     

Review of climate change impacts on marine aquaculture in the UK and Ireland

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Maggot-therapy in veterinary medicine

Maggot-therapy is the application of disinfected fly larvae to chronic wounds to debride the wound bed of necrotic tissue, reduce bacterial contamination and enhance the formation of healthy granulation tissue. Interest in the use of maggot-therapy in human medicine is growing as a result of the prevalence of antibiotic resistant bacteria. Maggot therapy, however, is used relatively little in veterinary medicine. Nevertheless, concern over antibiotic resistance and the increase in demand for organic husbandry and residue-free meat and milk, suggest that it is an option which merits further consideration.     

Identification of Polyphenols from Chilean Brown Seaweeds Extracts by LC-DAD-ESI-MS/MS

Polyphenol profiles were characterized in extracts of three Chilean brown seaweeds, Durvillaea antarctica (Chamisso) Hariot, Lessonia spicata (Suhr) Santelices, and Macrocystis integrifolia (Bory) by liquid chromatography with mass spectrometry detection (LC-MS/MS). Phlorotannins with different degrees of polymerization were identified in D. antarctica (trimers to octamers) and L. spicata (trimers to tetramers). No signals related to phlorotannins compounds were detected in M. integrifolia. L. spicata and M. integrifolia showed a great variety of flavonoid compounds in comparison with D. antarctica, mainly identified as glycoside forms in all the extracts. The antioxidant activity of brown seaweed extracts measured by ferric reducing power (FRAP) and oxygen radical absorbance capacity (ORAC) was significantly higher in D. antarctica, followed by M. integrifolia and L. spicata, in line with the total phenolic (TP) content. However, D. antarctica and M. integrifolia showed similar activity for free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) in spite of the differences found in TP content. D. antarctica as well as L. spicata would represent a potential source of phlorotannins, whereas M. integrifolia could be considered as an alternative source of flavonoids. The identification of polyphenols in extracts of Chilean brown seaweeds opens innovative opportunities for their use in the food and pharmaceutical industries.     

Re‐introduction of structurally complex wood jams promotes channel and habitat recovery from overwidening: Implications for river conservation

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Polymicrobial respiratory disease in pigs

Respiratory disease in pigs is common in modern pork production worldwide and is often referred to as porcine respiratory disease complex (PRDC). PRDC is polymicrobial in nature, and results from infection with various combinations of primary and secondary respiratory pathogens. As a true multifactorial disease, environmental conditions, population size, management strategies and pig-specific factors such as age and genetics also play critical roles in the outcome of PRDC. While non-infectious factors are important in the initiation and outcome of cases of PRDC, the focus of this review is on infectious factors only. There are a variety of viral and bacterial pathogens commonly associated with PRDC including porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae (MHYO) and Pasteurella multocida (PMULT). The pathogenesis of viral respiratory disease is typically associated with destruction of the mucocilliary apparatus and with interference and decrease of the function of pulmonary alveolar and intravascular macrophages. Bacterial pathogens often contribute to PRDC by activation of inflammation via enhanced cytokine responses. With recent advancements in pathogen detection methods, the importance of polymicrobial disease has become more evident, and identification of interactions of pathogens and their mechanisms of disease potentiation has become a topic of great interest. For example, combined infection of pigs with typically low pathogenic organisms like PCV2 and MHYO results in severe respiratory disease. Although the body of knowledge has advanced substantially in the last 15 years, much more needs to be learned about the pathogenesis and best practices for control of swine respiratory disease outbreaks caused by concurrent infection of two or more pathogens. This review discusses the latest findings on polymicrobial respiratory disease in pigs.