An Ecophisiological Proposal to Manage Natural Grasslands: A Long Term Trial

Natural grasslands on Southern Brazil comprise the so called “Rio de La Plata Grasslands” in South America. They are an important fodder source for ruminant pastoral systems and contribute to regional ecosystem services. Strength of these grasslands is its floristic diversity that poses a dilemma to farmers: how to choose management protocols that could be applied for hundreds of species. We propose to use a functional ecophysiological approach based on groups of grasses, the most abundant on aerial biomass of this natural grasslands. We clustered the most frequent grasses in two groups based on its leaf traits (leaf dry matter content and specific leaf area). These traits are functional clues to growth rhythms and nutritive value that could separate grasses in “resource capture” and “resource conservation” groups, both important for forage production and ecosystem services. Evaluating the most frequent grasses in each group we found they have an average of 375 degree-days, for “resource capture” and 750 degree-day for “resource conservation” groups, as its leaf elongation duration. So we evaluated a rotational grazing system based on this morphogenic trait for beef heifers rearing on natural grasslands from 2010 to 2019. We chose these experimental animals, as a model by its nutrient requirements and relevance for regional rearing and breeding systems. Our results indicate an average daily gain that is adequate to reach mating age and weight targets (0,3 kg/heifer/day to mate at 24 months) and allowed a higher stocking rate and gain per area when compared to regional standards (1,100 kg of live weight/ha and 370 kg/ha versus 600 and 70 kg/ha). All this animal performance was obtained without changing floristic diversity and also enhancing ecosystem services as CO2 sequestration. We concluded that this approach could allow farmers to conciliate the dilemma of production and conservation in pastoral ecosystems

Gastrointestinal strongyles burden monitoring in a flock of Zerasca sheep treated with homeopathy

Introdution The widespread use of conventional drugs in farm animals has resulted in anthelmintic resistance as well as the contamination of deleterious molecules in animal products and in the environment. Researchers are thus focusing on production systems that rely less on chemicals. The aim of this study was to monitor the gastrointestinal strongyle burden, blood count, body condition scores (BCS), and FAffa MAlan CHArt (FAMACHA) in a local Italian breed of sheep reared in natural conditions. Methods The study was carried out in a farm where homeopathy was utilised. Over a one-year period, faeces were sampled six times from ten Zerasca ewes to evaluate the fecal eggs count using a modified McMaster technique. At the same time, blood samples were collected to evaluate white blood cells, red blood cells, hemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and red cell distribution width. BCS and FAMACHA were also recorded. Results Results showed low parasite levels in most of the samples with the highest value in the spring. Blood parameters were within the normal range, with significant fluctuations during the sampling period. BCS values corresponded to an adequate nutritional condition of the animals and FAMACHA scores did not suggest a worrying state of anemia. Conclusions In this farm, a thorough monitoring of the gastrointestinal parasite burden together with a BCS and FAMACHA evaluation allowed the amount of chemical treatments to be limited, normally administered twice a year without laboratory tests

The Complexity of Flow Expansion and Electrical Flow Expansion

FlowExpansion is a network design problem, in which the input consists of a flow network and a set of candidate edges, which may be added to the network. Adding a candidate incurs given costs. The goal is to determine the cheapest set of candidate edges that, if added, allow the demands to be satisfied. FlowExpansion is a variant of the Minimum-Cost Flow problem with non-linear edge costs. We study FlowExpansion for both graph-theoretical and electrical flow networks. In the latter case this problem is also known as the Transmission Network Expansion Planning problem. We give a structured view over the complexity of the variants of FlowExpansion that arise from restricting, e.g., the graph classes, the capacities, or the number of sources and sinks. Our goal is to determine which restrictions have a crucial impact on the computational complexity. The results in this paper range from polynomial-time algorithms for the more restricted variants over NP-hardness proofs to proofs that certain variants are NP-hard to approximate even within a logarithmic factor of the optimal solution

Diagnostic accuracy of midtrimester antenatal ultrasound for multicystic dysplastic kidneys

OBJECTIVES: To establish the diagnostic accuracy of obstetric ultrasound at a tertiary fetal medicine centre in the prenatal detection of unilateral and bilateral MCDK in fetuses where this condition was suspected; and to undertake a systematic review of the literature on this topic. METHODS: Retrospective observational study of all cases with an antenatal diagnosis of either unilateral or bilateral MCDK referred to a regional tertiary fetal medicine unit between 1997 and 2015. Postnatal diagnosis was confirmed by postnatal ultrasound reports or postmortem examination. The accuracy for prenatal ultrasound in the diagnosis of MCDK was calculated. We also performed a review of the literature using a systematic search strategy, regarding the prenatal diagnosis and diagnostic accuracy of MCDK. RESULTS: We included 144 women in the analysis; 37 (25.7%) opted for pregnancy termination (due to unilateral MCDK with additional abnormalities, bilateral suspected MCDK or severe obstructive uropathy). In 126 women all pre- and postnatal data were available, including 104 livebirths; 19 who opted for TOP and where PM was available; and 3 that had an intrauterine fetal death. Two infants died shortly after birth, (due to known bilateral MCDK and known cranial vault defect). The overall number of postnatally confirmed MCDK was 100: of these 98 were diagnosed prenatally (true positive), while 2 were thought to be hydronephrosis prenatally (false negative) and the diagnosis of MCDK was made after birth. In 9 cases the initial antenatal diagnosis of suspected MCDK was revised, either later in pregnancy (n = 2) or postnatally (n = 7). The overall diagnostic accuracy of MCDK reported in the existing literature was found to range from 53.3 to 100%. MCDK was isolated in the majority of cases, while in 29% of cases was found to be associated with other renal and extra-renal fetal abnormalities. CONCLUSIONS: Our study suggests that the diagnostic accuracy for the use of antenatal ultrasound to detect postnatal MCDK was about 91% and can therefore be used to guide antenatal counselling. However, prenatal or postnatal revision of the diagnosis occurs in about 7% of cases and parents should be counselled appropriately

Type II enteropathy-associated T-cell lymphoma features a unique genomic profile with highly recurrent SETD2 alterations.

Enteropathy-associated T-cell lymphoma (EATL), a rare and aggressive intestinal malignancy of intraepithelial T lymphocytes, comprises two disease variants (EATL-I and EATL-II) differing in clinical characteristics and pathological features. Here we report findings derived from whole-exome sequencing of 15 EATL-II tumour-normal tissue pairs. The tumour suppressor gene SETD2 encoding a non-redundant H3K36-specific trimethyltransferase is altered in 14/15 cases (93%), mainly by loss-of-function mutations and/or loss of the corresponding locus (3p21.31). These alterations consistently correlate with defective H3K36 trimethylation. The JAK/STAT pathway comprises recurrent STAT5B (60%), JAK3 (46%) and SH2B3 (20%) mutations, including a STAT5B V712E activating variant. In addition, frequent mutations in TP53, BRAF and KRAS are observed. Conversely, in EATL-I, no SETD2, STAT5B or JAK3 mutations are found, and H3K36 trimethylation is preserved. This study describes SETD2 inactivation as EATL-II molecular hallmark, supports EATL-I and -II being two distinct entities, and defines potential new targets for therapeutic intervention

High photon count rates improve the quality of super-resolution fluorescence fluctuation spectroscopy

Probing the diffusion of molecules has become a routine measurement across the life sciences, chemistry and physics. It provides valuable insights into reaction dynamics, oligomerisation, molecular (re-)organisation or cellular heterogeneities. Fluorescence correlation spectroscopy (FCS) is one of the widely applied techniques to determine diffusion dynamics in two and three dimensions. This technique relies on the temporal autocorrelation of intensity fluctuations but recording these fluctuations has thus far been limited by the detection electronics, which could not efficiently and accurately time-tag photons at high count rates. This has until now restricted the range of measurable dye concentrations, as well as the data quality of the FCS recordings, especially in combination with super-resolution stimulated emission depletion (STED) nanoscopy. Here, we investigate the applicability and reliability of (STED-)FCS at high photon count rates (average intensities of more than 1 MHz) using novel detection equipment, namely hybrid detectors and real-time gigahertz sampling of the photon streams implemented on a commercial microscope. By measuring the diffusion of fluorophores in solution and cytoplasm of live cells, as well as in model and cellular membranes, we show that accurate diffusion and concentration measurements are possible in these previously inaccessible high photon count regimes. Specifically, it offers much greater flexibility of experiments with biological samples with highly variable intensity, e.g. due to a wide range of expression levels of fluorescent proteins. In this context, we highlight the independence of diffusion properties of cytosolic GFP in a concentration range of approx. 0.01-1 µm. We further show that higher photon count rates also allow for much shorter acquisition times, and improved data quality. Finally, this approach also pronouncedly increases the robustness of challenging live cell STED-FCS measurements of nanoscale diffusion dynamics, which we testify by confirming a free diffusion pattern for a fluorescent lipid analogue on the apical membrane of adherent cells. © The Author(s). Published by IOP Publishing Ltd

Eddy diffusivities for the convective boundary layer derived from LES spectral data

AbstractLarge Eddy Simulation (LES) spectral data and Taylor statistical diffusion theory are used to obtain Eddy diffusivities in a convective boundary layer. The derivation employs a fitting expression obtained from LES data for the vertical peak frequency. The vertical Eddy diffusivities are well behaved and show similar patterns and magnitudes as those derived from experimental spectral peak frequency data. In addition, this new vertical Eddy diffusivity was introduced into an advection diffusion equation which was solved by Generalized Integral Laplace Transform Technique (GILLT) method and validated with observed contaminant concentration data of the Copenhagen experiment. The results of this new approach are shown to agree with the measurements of Copenhagen