Sulfated Galactan from Palisada flagellifera Inhibits Toxic Effects of Lachesis muta Snake Venom

In Brazil, snakebites are a public health problem and accidents caused by Lachesis muta have the highest mortality index. Envenomation by L. muta is characterized by systemic (hypotension, bleeding and renal failure) and local effects (necrosis, pain and edema). The treatment to reverse the evolution of all the toxic effects is performed by injection of antivenom. However, such therapy does not effectively neutralize tissue damage or any other local effect, since in most cases victims delay seeking appropriate medical care. In this way, alternative therapies are in demand, and molecules from natural sources have been exhaustively tested. In this paper, we analyzed the inhibitory effect of a sulfated galactan obtained from the red seaweed Palisada flagellifera against some toxic activities of L. muta venom. Incubation of sulfated galactan with venom resulted in inhibition of hemolysis, coagulation, proteolysis, edema and hemorrhage. Neutralization of hemorrhage was also observed when the galactan was administered after or before the venom injection; thus mimicking a real in vivo situation. Moreover, the galactan blocked the edema caused by a phospholipase A₂ isolated from the same venom. Therefore, the galactan from P. flagellifera may represent a promising tool to treat envenomation by L. muta as a coadjuvant for the conventional antivenom.     

Semantic segmentation of citrus-orchard using deep neural networks and multispectral UAV-based imagery

Precision Agriculture - Accurately mapping farmlands is important for precision agriculture practices. Unmanned aerial vehicles (UAV) embedded with multispectral cameras are commonly used to map...     

纤维素酶高产菌株选育研究进展

本文综述和对比了各类产纤维素酶微生物的特点;介绍了产酶发酵条件优化、诱变育种及纤维素酶基因克隆等方法的研究进展;展望了选育高产菌株的研究趋势。     

Test of sampling methods to optimize the calibration of vine water status spatial models

Plant water status is one of the main factors affecting yield and quality in viticulture. Nevertheless, it is generally difficult to characterize it with enough precision for management purposes. In addition to its temporal variation, related to climate conditions, it has been shown that it is also spatially variable within the vineyard. In practical terms, this makes traditional reference measurements both too costly and time consuming to be affordable. In contrast, it has been shown that spatial variation of plant water status can be inferred from more accessible information, such as plant vigour in Mediterranean conditions. The main practical limitation for this approach is that the relationship between vigour measurements and plant water status is specific for each block and needs to be explicitly calibrated. Furthermore, a high number of measurements are usually required for this calibration. The objective of this work was to propose and test sampling methods to optimize the calibration of a specific spatial model of vine water status using the minimum number of measurements. Two model-based sampling methods commonly used in non-spatial modelling, Kennard and Stone (K&S) and Surface Response (SR) were considered, tested and discussed. Satisfactory results were obtained with both methods: with a sample size of 9 calibration sites, both sampling methods gave similar errors to the reference model (Root Mean Standard Error of Prediction, RMSEP = 0.1 MPa), which was calibrated with 49 sites. Taking into consideration the advantages and limitations of each method, K&S is considered to be better adapted for the case study presented. The proposed sampling approach could be extended to other spatial models used in precision agriculture in which ancillary variables can be used to explain most of the spatial variation for any agronomic information of interest.     

草本水杨梅的研究进展

草本水杨梅为多年生草本植物,资源丰富。草本水杨梅中含有黄酮、苯丙素、鞣质、挥发油、氨基酸和无机元素等多种化学成分,并具有抗病毒、抗炎、抗凝血及抗自由基等药理作用。本文对其化学成分和药理作用的研究进展进行综述。     

Male fertility and sex ratio at birth in red deer

Efforts to test sex ratio theory have focused mostly on females. However, when males possess traits that could enhance the reproductive success of sons, males would also benefit from the manipulation of the offspring sex ratio. We tested the prediction that more-fertile red deer males produce more sons. Our findings reveal that male fertility is positively related to the proportion of male offspring. We also show that there is a positive correlation between the percentage of morphologically normal spermatozoa (a main determinant of male fertility) and the proportion of male offspring. Thus, males may contribute significantly to biases in sex ratio at birth among mammals, creating the potential for conflicts of interest between males and females.     

Fish oil substitution by soybean oil in Sharpsnout seabream Diplodus puntazzo: Performance,fatty acid profile,and liver histology

The present study was conducted to determine the effect of soybean oil on the performance and liver histology in Sharpsnout seabream (Diplodus puntazzo) (initial body mass 35 g). Four experimental diets were formulated containing 0%, 25%, 50%, and 75% of soybean oil substituting fish oil. Fish were fed for 84 days. Increasing the level of soybean oil had no significant effects on growth and feed efficiency parameters. Biometrics, body composition, protein efficiency, and energy efficiency were not affected by the fish oil replacement. Muscle and liver fatty acids reflected fish oil substitution. Moreover, histology did not show statistical differences among treatments. Sharpsnout seabream juveniles can be fed with diets in which fish oil has been replaced with soybean oil at up to 75% of total lipid in the diet for a period of 84 days without affecting growth, feed efficiency, biometric parameters, and body composition.     

Red swamp crayfish,Procambarus clarkii,found in South Africa 22 years after attempted eradication

1. No freshwater crayfish are indigenous to continental Africa, but four species have been introduced to the continent. One of these is the North American red swamp crayfish Procambarus clarkii, which has been introduced into several African countries, mainly for aquaculture, and has had demonstrable impacts where it has escaped captivity. In South Africa, the documentation of this species in farm dams near Dullstroom and the adjacent Crocodile River in 1988 resulted in an eradication attempt in 1994, with unknown results. 2. In order to evaluate the status of P. clarkii in South Africa, dams on the previously invaded farm and the Crocodile River were sampled four times between December 2015 and June 2016 using visual surveys, trapping, dipnetting and electrofishing. This yielded a single reproductively active male P. clarkii from one of the farm ponds, while many other native aquatic species were found in high numbers. 3. It is clear from this study that P. clarkii was not eradicated in South Africa and that individuals have been surviving in the wild (i.e. outside captivity or cultivation) for at least 28 years in the location where it was introduced. Containment and eradication of the species are proposed as management actions, which have major importance in preventing undesirable further spread or translocation of this species into new aquatic environments in South Africa.     

Invasive Asian clam distribution pattern reveals minimal constraints to downstream dispersal and imperceptible ecological impacts

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Heritability estimates of larval and spat shell height in the Chilean blue mussel (Mytilus chilensis Hupe 1854) produced under controlled laboratory conditions

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