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Agricultural intensification has caused a decline of semi-natural grasslands and loss of botanical diversity, making agricultural fields dominated by Lolium perenne the main grassland system in large areas of Europe. Increased insight into the factors determining their vegetation composition and plant species richness is needed to improve the effectiveness of agri-environment schemes and to substantiate the benefits of organic over conventional agriculture. Our aims were (1) to determine the difference in vegetation composition (including species richness) between Lolium perenne -dominated fields of conventional and organic farms in a case study region in The Netherlands, and (2) to identify the soil and management related drivers behind this difference. We collected vegetation, soil and management data in grasslands of dairy farms under conventional or organic management (45 fields in total), and used multivariate statistics to determine the effect of fertilisation rates, grazing and cutting regime, and soil properties on plant species composition. In a next step we determined to what extent these abiotic drivers differ between organic and conventional farms. On average the organic fields appeared to have a c. 30% higher plant species richness compared to the conventional ones. Vegetation composition was most strongly influenced by groundwater level and nitrogen and phosphorus fertilisation rates, and to a lesser extent by plant-available soil potassium, mowing date, total soil nitrogen, potassium fertilisation rate, age of each field, and livestock (cow or sheep). In general, a low fertilisation rate, high groundwater level, late mowing, low level of plant-available potassium, high level of total soil nitrogen, old fields and the presence of sheep promote a high species richness. However, of these variables only nitrogen fertilisation rate and groundwater level differ significantly between the organic and conventional farms and are therefore likely to be the abiotic drivers of the difference in species richness and vegetation composition between the farm types. Of these two, the difference in nitrogen fertilisation rate is a direct result of a difference in management philosophy, but the difference in groundwater level is not. We hypothesize that the latter difference is caused by economic drivers, whereby a less productive soil is an incentive for a changeover to organic farming. If this is the case indeed, the application of agri-environment schemes would be most effective in less productive (and naturally more species-rich) sites. [ABSTRACT FROM AUTHOR]

To explore the causes of cochlear implantation and reference function of old electrical stimulation electrode in cochlear reimplantation in children. The causes, surgical methods and problems found during the operations of 24 cases of cochlear reimplantation in Henan Children's Hospital from June 2016 to April 2018 were analyzed. Twenty-three cases successfully completed the surgery of cochlear-reimplantation, and the remaining one case had approximately 1/3 of the anterior end of the residual cochlear electrode due to high resistance at the time of withdrawal of the electrodes. The causes of re-implantation were implant equipment failure (eleven cases), elevated impedance values of all electrodes after head trauma (two cases), and implant prolapse together with the electrode caused by a traffic accident (one case). The old stimulus electrode can provide an important reference to reduce the risk of operation and ensure the success of the reoperation. [ABSTRACT FROM AUTHOR]

Aim: To describe the imaging features of rosette-forming glioneuronal tumours (RGNTs) to enable accurate diagnosis.Materials and Methods: Image data and clinical findings for seven patients with histopathologically confirmed RGNTs were studied comprehensively.Results: Six neoplasms were located near the midline and all were relatively well circumscribed. Most lesions were hypointense on T1-weighted images and hyperintense on T2-weighted images. Furthermore, five tumours were hypointense on diffusion-weighted imaging (DWI). On computed tomography (CT), the solid tumour portions showed hypo-attenuation compared with brain parenchyma. Obvious calcification was found in two cases, and hydrocephalus was seen in five. Cerebrospinal fluid (CSF) dissemination and multiple satellite lesions were not observed in these cases. Haemorrhage was found in one case. The "green bell pepper sign" was present in five cases on gadolinium-enhanced magnetic resonance imaging (MRI). Each of the patients accepted surgical treatment, and no recurrences occurred during follow-up.Conclusion: RGNTs are very rare mixed glioneuronal tumours and mostly affect young people. They are usually hypointense on T1-weighted images and DWI, hyperintense on T2-weighted images, and hypo-attenuated on CT images. The "green bell pepper sign" after gadolinium enhancement, intratumoural haemorrhage, CSF dissemination, and multiple satellite lesions provide additional clues to the correct diagnosis. A relatively well-demarcated tumour with these features and a midline location should raise suspicion of an RGNT. [ABSTRACT FROM AUTHOR]

Semaphorin3A (Sema3A) is a major inhibitory factor of optic nerve (ON) regeneration post-injury. Many microRNAs (miRNAs) are expressed specifically in the mammalian brain and retina and are dynamically regulated during development, suggesting that this group of miRNAs may be associated with neural development. We found that microRNA-30b (miR-30b) bound to the three prime untranslated region (3′ UTR) of Sema3A and inhibited the expression of Sema3A mRNA. The mRNA expression level of miR-30b and the protein expression levels of Sema3A, Neuropilin1 (NRP1), PlexinA1 (PlexA1), phosphorylated p38MAPK (p-p38MAPK), and active caspase-3 were all upregulated in retinas from rats with a damaged ON relative to those with an intact ON. Transfection of cultured retinal ganglion cells (RGCs) with an miR-30b mimic led to decreased levels of Sema3A, NRP1, PlexA1, p-p38MAPK, and active caspase-3 protein expression, as well as axon elongation and reduced levels of apoptosis. These findings provide evidence that miR-30b inhibits Sema3A expression. Decreased Sema3A expression promotes axon outgrowth in RGCs due to reduced levels of Sema3A binding to NRP1 and PlexA1 and simultaneously reduces apoptosis by inhibiting the p38MAPK and caspase-3 pathways. Our findings provide the first evidence that miR-30b-mediated Sema3A downregulation may serve as a new strategy for the clinical treatment of ON injury. [ABSTRACT FROM AUTHOR]