Concentration fluctuations of large Stokes number particles in a one-dimensional random velocity field

We analyze the behavior of an ensemble of inertial particles in a one-dimensional smooth Gaussian velocity field, in the limit of large inertia, but considering a finite correlation time for the random field. We derive in this limit a perturbative scheme for the calculation of the concentration correlation and of the particle relative velocity distribution, providing analytical expressions for the concentration fluctuation amplitude, its correlation length, and the modification in the particle pair relative velocity variance. The amplitude of the concentration fluctuations is characterized by slow decay at large inertia and a much larger correlation length than that of the random field. The fluctuation structure in velocity space is very different from predictions from short-time correlated random velocity fields, with only few particle pairs crossing at sufficiently small relative velocity to produce correlations. Concentration fluctuations are associated with depletion of the relative velocity variance of colliding particles.Comment: 8 pages, 1 figure, revtex

Effects of the antioxidant crocin on frozen-thawed buffalo (Bubalus bubalis) sperm

This work aimed to evaluate the effect of crocin on frozen-thawed sperm quality in buffalo. Spermatozoa were incubated in Tyrode’s Albumin Lactate Pyruvate medium supplemented with 0, 0.5, 1, and 2 mM crocin for 2 h. Sperm motility was evaluated by phase-contrast microscopy, viability and acrosome integrity by Trypan blue Giemsa staining, and membrane functional integrity by the hypoosmotic swelling test. The DNA fragmentation was evaluated by Tunel and ROS levels by spectrofluorometric analysis. The treatment with 2 mM of crocin increased (P <.05) sperm membrane functional integrity compared to the control group (59.1 ± 1.6 vs 53.3 ± 1.5) and reduced sperm DNA fragmentation, compared to the other groups (11.3 ± 1.1, 13.3 ± 1.2, 13.6 ± 1.2 and 6.0 ± 0.7, respectively in 0, 0.5, 1 and 2 mM crocin; P <.01). Finally, a dose-dependent decrease (P <.01) in superoxide anion production in the presence of crocin was observed, as indicated by Dihydroethidium values (922.6 ± 13.0, 596.8 ± 7.4, 498.9 ± 5.3 and 421.4 ± 5.0 a.u., respectively in 0, 0.5, 1 and 2 mM crocin; P <.01). The results of this study demonstrated a positive effect of 2 mM crocin on frozen-thawed buffalo sperm, as indicated by the improvement of sperm membrane integrity and the reduction of DNA fragmentation and ROS levels.Highlights Crocin improves buffalo sperm quality. Crocin improves sperm membrane integrity and reduces DNA fragmentation. Crocin decreases oxidative stress in buffalo sperm

Clinical and prognostic implications of the genetic diagnosis of hereditary NET syndromes in asymptomatic patients

Neuroendocrine tumors (NETs) can be sporadic or they can arise in complex hereditary syndromes. Patients with hereditary NETs can be identified before the development of tumors by performing genetic screenings. The aim of the study was to evaluate the clinical and prognostic impact of a preclinical genetic screening in subjects with hereditary NET syndromes. 46 subjects referred for hereditary NET syndrome [22 MEN1, 12 MEN2, 12 Familial Paragangliomatosis (FPGL)] were enrolled and divided in 2 groups (group A, 20 subjects with clinical appearance of NET before the genetic diagnosis; group B, 26 subjects with genetic diagnosis of hereditary NET syndromes before the clinical appearance of NETs). The main outcome measures were severity of disease, prognosis, and survival. The rate of surgery for MEN1-, MEN2-, FPGL4-related tumors was 90% in group A and 35% in group B (p<0.01). Both symptoms related to tumors and symptoms related to therapies were significantly less frequent in group B than in group A (p<0.05). Tumor stage was locally advanced or metastatic in 50% of group A and in no one of group B (p<0.01). The mortality rate was 25% in group A and 0% in group B (p<0.05). An early genetic screening for hereditary NET syndromes results in an improvement in clinical presentation and morbidity. A potential impact of the genetic screening on the mortality rate of these subjects is suggested and needs to be investigated in further and more appropriate studies

Roles for CEP170 in cilia function and dynein-2 assembly

Primary cilia are essential eukaryotic organelles required for signalling and secretion. Dynein-2 is a microtubule-motor protein complex and is required for ciliogenesis via its role in facilitating retrograde intraflagellar transport (IFT) from the cilia tip to the cell body. Dynein-2 must be assembled and loaded onto IFT trains for entry into cilia for this process to occur, but how dynein-2 is assembled and how it is recycled back into a cilium remain poorly understood. Here, we identify centrosomal protein of 170 kDa (CEP170) as a dynein-2-interacting protein in mammalian cells. We show that loss of CEP170 perturbs intraflagellar transport and hedgehog signalling, and alters the stability of dynein-2 holoenzyme complex. Together, our data indicate a role for CEP170 in supporting cilia function and dynein-2 assembly

Autoregulation of RCO by Low-Affinity Binding Modulates Cytokinin Action and Shapes Leaf Diversity

Mechanisms through which the evolution of gene regulation causes morphological diversity are largely unclear. The tremendous shape variation among plant leaves offers attractive opportunities to address this question. In cruciferous plants, the REDUCED COMPLEXITY (RCO) homeodomain protein evolved via gene duplication and acquired a novel expression domain that contributed to leaf shape diversity. However, the molecular pathways through which RCO regulates leaf growth are unknown. A key question is to identify genome-wide transcriptional targets of RCO and the DNA sequences to which RCO binds. We investigate this question using Cardamine hirsuta, which has complex leaves, and its relative Arabidopsis thaliana, which evolved simple leaves through loss of RCO. We demonstrate that RCO directly regulates genes controlling homeostasis of the hormone cytokinin to repress growth at the leaf base. Elevating cytokinin signaling in the RCO expression domain is sufficient to both transform A. thaliana simple leaves into complex ones and partially bypass the requirement for RCO in C. hirsuta complex leaf development. We also identify RCO as its own target gene. RCO directly represses its own transcription via an array of low-affinity binding sites, which evolved after RCO duplicated from its progenitor sequence. This autorepression is required to limit RCO expression. Thus, evolution of low-affinity binding sites created a negative autoregulatory loop that facilitated leaf shape evolution by defining RCO expression and fine-tuning cytokinin activity. In summary, we identify a transcriptional mechanism through which conflicts between novelty and pleiotropy are resolved during evolution and lead to morphological differences between species. Hajheidari et al. identify target genes for the RCO homeodomain protein that drove leaf shape diversity. They show that RCO regulates growth via orchestrating homeostasis for the hormone cytokinin and that it also represses its own transcription via low-affinity binding sites. This autorepression helps delimit RCO expression and shape leaf form

Agronomical valorization of eluates from the industrial production of microorganisms: Chemical, microbiological, and ecotoxicological assessment of a novel putative biostimulant

Plant Biostimulants (BSs) are a valid supplement to be considered for the integration of conventional fertilization practices. Research in the BS field keeps providing alternative products of various origin, which can be employed in organic and conventional agriculture. In this study, we investigated the biostimulant activity of the eluate obtained as a by-product from the industrial production of lactic acid bacteria on bare agricultural soil. Eluates utilization is in line with the circular economy principle, creating economical value for an industrial waste product. The research focused on the study of physical, chemical, biochemical, and microbiological changes occurring in agricultural soil treated with the biowaste eluate, applied at three different dosages. The final aim was to demonstrate if, and to what extent, the application of the eluate improved soil quality parameters and enhanced the presence of beneficial soil-borne microbial communities. Results indicate that a single application at the two lower dosages does not have a pronounced effect on the soil chemical parameters tested, and neither on the biochemical proprieties. Only the higher dosage applied reported an improvement in the enzymatic activities of β-glucosidase and urease and in the chemical composition, showing a higher content of total, nitric and ammonia N, total K, and higher humification rate. On the other hand, microbial communities were strongly influenced at all dosages, showing a decrease in the bacterial biodiversity and an increase in the fungal biodiversity. Bioinformatic analysis revealed that some Operative Taxonomic Units (OTUs) promoted by the eluate application, belong to known plant growth promoting microbes. Some other OTUs, negatively influenced were attributed to known plant pathogens, mainly Fusarium spp. Finally, the ecotoxicological parameters were also determined and allowed to establish that no toxic effect occurred upon eluate applications onto soil

Central vein sign differentiates Multiple Sclerosis from central nervous system inflammatory vasculopathies.

In multiple sclerosis (MS), magnetic resonance imaging (MRI) is a sensitive tool for detecting white matter lesions, but its diagnostic specificity is still suboptimal; ambiguous cases are frequent in clinical practice. Detection of perivenular lesions in the brain (the "central vein sign") improves the pathological specificity of MS diagnosis, but comprehensive evaluation of this MRI biomarker in MS-mimicking inflammatory and/or autoimmune diseases, such as central nervous system (CNS) inflammatory vasculopathies, is lacking. In a multicenter study, we assessed the frequency of perivenular lesions in MS versus systemic autoimmune diseases with CNS involvement and primary angiitis of the CNS (PACNS). In 31 patients with inflammatory CNS vasculopathies and 52 with relapsing-remitting MS, 3-dimensional T2*-weighted and T2-fluid-attenuated inversion recovery images were obtained during a single MRI acquisition after gadolinium injection. For each lesion, the central vein sign was evaluated according to consensus guidelines. For each patient, lesion count, volume, and brain location, as well as fulfillment of dissemination in space MRI criteria, were assessed. MS showed higher frequency of perivenular lesions (median = 88%) than did inflammatory CNS vasculopathies (14%), without overlap between groups or differences between 3T and 1.5T MRI. Among inflammatory vasculopathies, Behçet disease showed the highest median frequency of perivenular lesions (34%), followed by PACNS (14%), antiphospholipid syndromes (12%), Sjögren syndrome (11%), and systemic lupus erythematosus (0%). When a threshold of 50% perivenular lesions was applied, central vein sign discriminated MS from inflammatory vasculopathies with a diagnostic accuracy of 100%. The central vein sign differentiates inflammatory CNS vasculopathies from MS at standard clinical magnetic field strengths. Ann Neurol 2018;83:283-294

LABs Fermentation Side-Product Positively Influences Rhizosphere and Plant Growth in Greenhouse Lettuce and Tomatoes

New agronomical policies aim to achieve greener agricultural systems, sustainable fertilizers and fungicides, a reduction in Greenhouse gases (GHG), and an increase in circular economic models. In this context, new solutions are needed for the market, but it is necessary to carefully assess both their efficacy and their ecological impact. Previously, we reported the biostimulatory activity on soil microbiome for a side-product from Lactic Acid Bacteria (LABs) fermentation: a concentrated post-centrifugation eluate. In the present study, we investigated whether this solution could partially substitute mineral N (N70% + N30% from eluate) in a fertigation (N100% vs. N70%) regime for tomato and lettuce under greenhouse conditions. The impact of the application was investigated through plant physiological parameters (number and weight of ripened fruits, shoots, and roots biomass) and biodiversity of the rhizosphere microbial composition of bacteria and fungi (High-Throughput Sequencing-HTS). The eluate (i) enhanced the plant canopy in lettuce; (ii) increased the shoot/root biomass ratio in both tomato and lettuce; and (iii) increased the harvest and delayed fruit ripening in tomato. Moreover, we found a strong correlation between the eluate and the enrichment for OTUs of plant-growth-promoting microbes (PGPMs) such as Sphingomonas sediminicola, Knoellia subterranean, and Funneliformis mosseae. These findings suggest that integrating the eluate was beneficial for the plant growth, performance, and yield in both tomato and lettuce, and additionally, it enriched specialized functional microbial communities in the rhizosphere. Further studies will investigate the underlying mechanisms regulating the selective activity of the eluate toward PGPMs and its biostimulatory activity towards target crops