Calcium phosphate particles coated with humic substances: A potential plant biostimulant from circular economy

Nowadays, the use of biostimulants to reduce agrochemical input is a major trend in agriculture. In this work, we report on calcium phosphate particles (CaP) recovered from the circular economy, combined with natural humic substances (HSs), to produce a plant biostimulant. CaPs were obtained by the thermal treatment of Salmo salar bones and were subsequently functionalized with HSs by soaking in a HS water solution. The obtained materials were characterized, showing that the functionalization with HS did not sort any effect on the bulk physicochemical properties of CaP, with the exception of the surface charge that was found to get more negative. Finally, the effect of the materials on nutrient uptake and translocation in the early stages of development (up to 20 days) of two model species of interest for horticulture, Valerianella locusta and Diplotaxis tenuifolia, was assessed. Both species exhibited a similar tendency to accumulate Ca and P in hypogeal tissues, but showed different reactions to the treatments in terms of translocation to the leaves. CaP and CaP\u2013HS treatments lead to an increase of P accumulation in the leaves of D. tenuifolia, while the treatment with HS was found to increase only the concentration of Ca in V. locusta leaves. A low biostimulating effect on both plants\u2019 growth was observed, and was mainly scribed to the low concentration of HS in the tested materials. In the end, the obtained material showed promising results in virtue of its potential to elicit phosphorous uptake and foliar translocation by plants

Progesterone action in human tissues: regulation by progesterone receptor (PR) isoform expression, nuclear positioning and coregulator expression

Progesterone is a critical regulator of normal female reproductive function, with diverse tissue-specific effects in the human. The effects of progesterone are mediated by its nuclear receptor (PR) that is expressed as two isoforms, PRA and PRB, which are virtually identical except that PRA lacks 164 amino acids that are present at the N-terminus of PRB. Considerable in vitro evidence suggests that the two PRs are functionally distinct and in animals, tissue-specific distribution patterns of PRA and PRB may account for some of the diversity of progesterone effects. In the human, PRA and PRB are equivalently expressed in most target cells, suggesting that alternative mechanisms control the diversity of progesterone actions. PR mediates the effects of progesterone by association with a range of coregulatory proteins and binding to specific target sequences in progesterone-regulated gene promoters. Ligand activation of PR results in redistribution into discrete subnuclear foci that are detectable by immunofluorescence, probably representing aggregates of multiple transcriptionally active PR-coregulator complexes. PR foci are aberrant in cancers, suggesting that the coregulator composition and number of complexes is altered. A large family of coregulators is now described and the range of proteins known to bind PR exceeds the complement required for transcriptional activation, suggesting that in the human, tissue-specific coregulator expression may modulate progesterone response. In this review, we examine the role of nuclear localization of PR, coregulator association and tissue-specific expression in modulating progesterone action in the human

How doctors generate diagnostic hypotheses: a study of radiological diagnosis with functional magnetic resonance imaging.

In medical practice, diagnostic hypotheses are often made by physicians in the first moments of contact with patients; sometimes even before they report their symptoms. We propose that generation of diagnostic hypotheses in this context is the result of cognitive processes subserved by brain mechanisms that are similar to those involved in naming objects or concepts in everyday life

Bell-like homeodomain selectively regulates the high-irradiance response of phytochrome A

Plant responses mediated by phytochrome A display a first phase saturated by transient light signals and a second phase requiring sustained excitation with far-red light (FR). These discrete outcomes, respectively so-called very-low-fluence response (VLFR) and high-irradiance response (HIR), are appropriate in different environmental and developmental contexts but the mechanisms that regulate the switch remain unexplored. Promoter analysis of a light-responsive target gene revealed a motif necessary for HIR but not for VLFR. This motif is required for binding of the Bell-like homeodomain 1 (BLH1) to the promoter in in vitro and in yeast 1-hybrid experiments. Promoter substitutions that increased BLH1 binding also enhanced HIR. blh1 mutants showed reduced responses to continuous FR and to deep canopy shadelight, but they retained normal responses to pulsed FR or red light and unfiltered sunlight. BLH1 enhanced BLH1 expression and its promotion by FR. We conclude that BLH1 specifically regulates HIR and not VLFR of phytochrome A

Between the sea and the land: the livelihood of estuarine people in southeastern Brazil Entre o mar e a terra: modos de vida de comunidades estuarinas no sudeste do Brasil

The central focus of this study is to characterize and compare the livelihood strategies of two coastal communities from the estuarine region of Ribeira Valley (São Paulo State, Southeastern Brazil), analyzing the interplay among four economic activities: small-scale agriculture, fishing, tourism-related jobs, and extraction of non-timber vegetal resources. The local people of these communities are mostly Caiçara, the native inhabitants of southeastern Brazilian coast, in an Atlantic forest area. The miscegenation of Amerindians, European colonizers, and African Brazilians gave rise to the Caiçara people, whose subsistence was originally based on small-scale itinerant agriculture, small-scale fishery, and some extraction of forest products. Their livelihoods activities changed through time: agricultural practices were gradually abandoned, while fishing grew in importance. Recently, tourism-related jobs and the extraction of non-timber vegetal resources acquired a key role in the estuarine Caiçara livelihood. After an historical overview, we focus our analysis on the local factors and external pressures affecting the combination of these activities.<br>O objetivo central deste artigo é caracterizar e comparar as estratégias dos meios de vida de duas comunidades da região estuarina do vale de Ribeira (Estado de São Paulo), analisando a inter-relação entre quatro atividades econômicas: agricultura de pequena escala, pesca, trabalhos relacionados ao turismo e extração de recursos vegetais não madeireiros. Os habitantes destas comunidades são na maior parte Caiçaras, nativos da costa sudeste do Brasil, vivendo em área do domínio Mata Atlântica. Caiçaras são descendentes de ameríndios e colonizadores europeus, com influências mais recentes de escravos africanos. Sua subsistência era baseada originalmente na agricultura itinerante de pequena escala, na pesca artesanal e, em menor grau, na extração de produtos florestais. Suas atividades de subsistência mudaram com o tempo: as práticas agrícolas foram abandonadas gradualmente, enquanto a pesca cresceu em importância. Recentemente, as atividades econômicas relacionadas ao turismo e à extração de recursos vegetais não madeireiros adquiriram um papel chave nos meios de subsistência dos Caiçaras desta região estuarina. Após uma contextualização histórica, nós focalizamos na análise dos fatores locais e das pressões externas que afetam a combinação destas atividades