Ground reference data for sugarcane biomass estimation in São Paulo state, Brazil

In order to make effective decisions on sustainable development, it is essential for sugarcane-producing countries to take into account sugarcane acreage and sugarcane production dynamics. The availability of sugarcane biophysical data along the growth season is key to an effective mapping of such dynamics, especially to tune agronomic models and to cross-validate indirect satellite measurements. Here, we introduce a dataset comprising 3,500 sugarcane observations collected from October 2014 until October 2015 at four fields in the São Paulo state (Brazil). The campaign included both non-destructive measurements of plant biometrics and destructive biomass weighing procedures. The acquisition plan was designed to maximize cost-effectiveness and minimize field-invasiveness, hence the non-destructive measurements outnumber the destructive ones. To compensate for such imbalance, a method to convert the measured biometrics into biomass estimates, based on the empirical adjustment of allometric models, is proposed. In addition, the paper addresses the precisions associated to the ground measurements and derived metrics. The presented growth dynamics and associated precisions can be adopted when designing new sugarcane measurement campaigns.5FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2013/50942-

UV and genotoxic stress induce ATR relocalization in mouse spermatocytes

During meiosis, phosphorylation of H2AX is one of the earliest cellular responses to the generation of DNA double-strand breaks (DSBs) by the SPO11 topoisomerase. ATM is the kinase which mediates the formation of phosphorylated H2AX (H2AX) meiotic foci, while ATR is the kinase which signals chromosome asynapsis at the level of the XY bivalent. To investigate the possible role of ATR also in DNA damage signalling in meiotic cells, we studied the effect of UV radiation and chemotherapy drugs on H2AX phosphorylation and ATR relocalization in mouse pachytene spermatocytes. Here, we report that UV, a single strand break DNA-damaging agent, induces ATR relocalization from the XY sex body to nuclear foci and intense H2AX phosphorylation. Other DNA damage proteins such as MDC1, NBS1 and 53BP1 showed a similar relocalization following UVA microirradiation of spermatocytes. We found that DNA damage induced by UV increased the intensity and the number of H2AX foci also in Atm null spermatocytes. Inhibition of RNA synthesis was found to induce the formation of H2AX foci, but it did not influence the DNA damage response to UV irradiation. Finally, exposure of spermatocytes to double strand break DNA-damaging agents such as cisplatin, bleomycin or etoposide also induced ATR relocalization and intense H2AX phosphorylation and led to anomalies in synaptonemal assembly. Our results demonstrate that DNA damage induced by genotoxic stress can activate ATR and influence meiotic chromatin remodelling through H2AX phosphorylation, likely as part of a response which normally ensures germ cell genomic integrity

An accurate approach for computational pKa determination of phenolic compounds

Computational chemistry is a valuable tool, as it allows for in silico prediction of key parameters of novel compounds, such as pKa. In the framework of computational pKa determination, the literature offers several approaches based on different level of theories, functionals and continuum solvation models. However, correction factors are often used to provide reliable models that adequately predict pKa. In this work, an accurate protocol based on a direct approach is proposed for computing phenols pKa. Importantly, this methodology does not require the use of correction factors or mathematical fitting, making it highly practical, easy to use and fast. Above all, DFT calculations performed in the presence two explicit water molecules using CAM-B3LYP functional with 6-311G+dp basis set and a solvation model based on density (SMD) led to accurate pKa values. In particular, calculations performed on a series of 13 differently substituted phenols provided reliable results, with a mean absolute error of 0.3. Furthermore, the model achieves accurate results with -CN and -NO2 substituents, which are usually excluded from computational pKa studies, enabling easy and reliable pKa determination in a wide range of phenols

Vegetation characterization through the use of precipitation-affected SAR signals

Current space-based SAR offers unique opportunities to classify vegetation types and to monitor vegetation growth due to its frequent acquisitions and its sensitivity to vegetation geometry. However, SAR signals also experience frequent temporal fluctuations caused by precipitation events, complicating the mapping and monitoring of vegetation. In this paper, we show that the influence of a priori known precipitation events on the signals can be used advantageously for the classification of vegetation conditions. For this, we exploit the change in Sentinel-1 backscatter response between consecutive acquisitions under varying wetness conditions, which we show is dependent on the state of vegetation. The performance further improves when a priori information on the soil type is taken into account.1010FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2013/50943-

SOHLH1 and SOHLH2 control Kit expression during postnatal male germ cell development

How Kit expression is regulated in the germline remains unknown. SOHLH1 and SOHLH2, two bHLH transcription factors specifically expressed in germ cells, are involved in spermatogonia and oocyte differentiation. In the male, deletion of each factor causes loss of Kit-expressing spermatogonia in the prepuberal testis. In the female, SOHLH1 and SOHLH2 ablations cause oocyte loss in the neonatal ovary. To investigate whether Kit expression is regulated by these two factors in male germ cells, we examined SOHLH1 and SOHLH2 expression during fetal and postnatal mouse development. We found a strong positive correlation between Kit and the two transcription factors only in postnatal spermatogonia. SOHLH2 was enriched in undifferentiated spermatogonia, whereas SOHLH1 expression was maximal at Kit-dependent stages. Expression of SOHLH1, but not SOHLH2, was increased in postnatal mitotic germ cells by treatment with all-trans retinoic acid. We found that E-box sequences within the Kit promoter and its first intron can be transactivated in transfection experiments overexpressing Sohlh1 or Sohlh2. Co-transfection of both factors showed a cooperative effect. EMSA experiments showed that SOHLH1 and SOHLH2 can independently and cooperatively bind an E-box-containing probe. In vivo co-immunoprecipitations indicated that the two proteins interact and overexpression of both factors increases endogenous Kit expression in embryonic stem cells. SOHLH1 was found by ChIP analysis to occupy an E-box-containing region within the Kit promoter in spermatogonia chromatin. Our results suggest that SOHLH1 and SOHLH2 directly stimulate Kit transcription in postnatal spermatogonia, thus activating the signaling involved in spermatogonia differentiation and spermatogenetic progression

Transcriptome analysis of differentiating spermatogonia stimulated with kit ligand

Kit ligand (KL) is a survival factor and a mitogenic stimulus for differentiating spermatogonia. However, it is not known whether KL also plays a role in the differentiative events that lead to meiotic entry of these cells. We performed a wide genome analysis of difference in gene expression induced by treatment with KL of spermatogonia from 7-day-old mice, using gene chips spanning the whole mouse genome. The analysis revealed that the pattern of RNA expression induced by KL is compatible with the qualitative changes of the cell cycle that occur during the subsequent cell divisions in type A and B spermatogonia, i.e. the progressive lengthening of the S phase and the shortening of the G2/M transition. Moreover, KL up-regulates in differentiating spermatogonia the expression of early meiotic genes (for instance: Lhx8, Nek1, Rnf141, Xrcc3, Tpo1, Tbca, Xrcc2, Mesp1, Phf7, Rtel1), whereas it down-regulates typical spermatogonial markers (for instance: Pole, Ptgs2, Zfpm2, Egr2, Egr3, Gsk3b, Hnrpa1, Fst, Ptch2). Since KL modifies the expression of several genes known to be up-regulated or down-regulated in spermatogonia during the transition from the mitotic to the meiotic cell cycle, these results are consistent with a role of the KL/kit interaction in the induction of their meiotic differentiation

Intensidades da poda seca e do desbaste de cacho na composição da uva Cabernet Sauvignon.

A pesquisa foi realizada durante quatro anos, num vinhedo de Cabernet Sauvignon (Vitis vinifera L.), em Bento Gonçalves-RS. O objetivo foi determinar o efeito das intensidades da poda seca e do desbaste de cacho em variáveis relacionadas aos componentes de produção da videira e à composição do mosto de uva. Os tratamentos consistiram em dois níveis de poda seca - curta e longa - e quatro de desbaste de cacho (%) - 0; 25; 50 e 75 -; com cinco repetições. O delineamento experimental foi o em blocos casualizados, com os tratamentos em parcelas subdivididas. Os resultados mostram que a poda seca e o desbaste de cacho tiveram efeito altamente significativo na produtividade do vinhedo que, na média dos quatro anos, variou de 10.971 kg/ha ? poda curta, 75% de desbaste ? a 32.819 kg/ha ? poda longa, 0% de desbaste. Houve, também, efeito significativo na produtividade por gema, peso de ramos podados por gema e por hectare, área foliar/peso fresco do fruto e produtividade/peso de ramos podados. Entretanto, o efeito nas variáveis relacionadas a açúcar e acidez do mosto da uva foi pouco expressivo. O componente 1 da análise de componentes principais discriminou o tratamento poda curta a 75% de desbaste de cacho dos tratamentos poda longa-0% de desbaste e poda longa-25% de desbaste