Livestock intensification and environmental sustainability: An analysis based on pasture management scenarios in the brazilian savanna.

Brazil's major beef production occurs in the Cerrado, predominantly as extensive pastures that covers ∼50 Mha of the biome, of which approximately 2/3 show signs of degradation. Pasture recovery is now a key environmental policy, as it improves land use efficiency and soil carbon sequestration. However, as intensification leads to higher cattle stocking rates and external inputs (fertilizers, liming, etc.), the impact of improved pastures on greenhouse gas mitigation is still debatable. This study focused on the Cerrado biome and aimed to (i) quantify soil carbon stock changes under different scenarios of management and recovery of degraded pastures. In addition, (ii) the potential for capturing carbon in the soil to mitigate emissions of greenhouse gases (GHG) by the intensification of pastures was evaluated. Soil C stock changes (0-20 cm) were assessed using the Century model version 4.5, which had been previously validated for the region. Model parameters were adjusted for three pastures classes (degraded, intermediately degraded, and not degraded) within a time-series (1985-2020) of land use maps for the Cerrado, serving as baselines. Scenarios of pasture intensification were modeled against these baselines, and an analysis was carried out on the estimated changes in soil C stock and greenhouse gas balance. Before the intensification scenario (year 2020), the total carbon stock was estimated to be ∼1830 Mt for the whole pasture area, whose spatial distribution corresponded to edaphoclimatic contrasts and pasture conditions. The highest soil organic carbon stocks were observed in the non-degraded pastures. With the increase in carrying capacity, beef production is estimated to potentially increase by 1/3 due to the recovery of degraded areas through intensive management. This increase would be sufficient to meet the projected ∼12% increase in Brazil's livestock production by the end of the decade if all pasture areas are restored, which is much possibly an unrealistic scenario as not all degraded areas are suitable for crops or can successfully improve pasture yield. In addition, the increase in soil C stocks was only sufficient to compensate for 27% and 42% of the GHG emissions resulting from intensification in areas with intermediate and severe degradation, respectively. Therefore, to strike a balance between economic considerations and environmental impact, additional strategies are needed to reduce GHG emissions and/or enhance C sinks, such as increasing tree density on farms. From this perspective, implementing livestock intensification at the landscape scale can promote C stocks and the diversity of ecosystem services, opening the possibility of ecosystem restoration.

Endocannabinoid signaling in astrocytes.

The study of the astrocytic contribution to brain functions has been growing in popularity in the neuroscience field. In the last years, and especially since the demonstration of the involvement of astrocytes in synaptic functions, the astrocyte field has revealed multiple functions of these cells that seemed inconceivable not long ago. In parallel, cannabinoid investigation has also identified different ways by which cannabinoids are able to interact with these cells, modify their functions, alter their communication with neurons and impact behavior. In this review, we will describe the expression of different endocannabinoid system members in astrocytes. Moreover, we will relate the latest findings regarding cannabinoid modulation of some of the most relevant astroglial functions, namely calcium (Ca2+ ) dynamics, gliotransmission, metabolism, and inflammation.

The role of acetylated cyclooxygenase-2 in the biosynthesis of resolvin precursors derived from eicosapentaenoic acid.

Specialized pro-resolving lipid mediators (SPMs) are natural bioactive agents actively involved in inflammation resolution. SPMs act when uncontrolled inflammatory processes are developed, for instance, in patients of COVID-19 or other diseases. The so-called resolution pharmacology aims at developing new treatments based on the use of SPMs as agonists, which promote inflammation resolution without unwanted side effects. It has been shown that the biosynthesis of SPMs called eicosapentaenoic acid (EPA)-derived E-series resolvins is initiated by aspirin-acetylated COX-2 from EPA, leading to 18-hydroperoxy-eicosapentaenoic acid (18-HpEPE). However, there are many open questions concerning the intriguing role of aspirin in the molecular mechanism of resolvin formation. Our MD simulations, combined with QM/MM calculations, show that the potential energy barriers for the H16-abstraction from EPA, required for forming 18-HpEPE, are higher than for the H13-abstraction, thus explaining why 18-HpEPE is a marginal product of COX-2 catalysis. By contrast, in the aspirin-acetylated COX-2/EPA complex, the H16proS-abstraction energy barriers are somewhat lower than the H13proS energy barriers and much smaller than the H16-transfer barriers in the wild type COX-2/EPA system. Those results agree with the experimental observation that aspirin favours the synthesis of several SPMs known as aspirin-triggered resolvins. In the following step of the catalytic mechanism, the calculated O2 addition to C18 is preferred versus the addition to C14 which also agrees with 18R-HEPE and 18S-HEPE being the main products from EPA in aspirin-acetylated COX-2.

The extrinsic nature of double broadband photoluminescence from the BaTiO3 perovskite: generation of white light emitters.

The electronic properties of BaTiO3 perovskite oxides are not completely understood, despite their excellent electro-optical performance and potential for light generation. Particularly, when there is multiple peak formation in the photoluminescence spectra, their origins are not discussed. Their luminescence spectra reveal an unexpected thermodynamic relationship between the core excitonic states and the surface of the BaTiO3. These results give a broad insight into the origins of the emission properties of perovskite oxides. The self-trapped excitons contribution to the broadbands highlights their extrinsic origin. Through spectroscopy techniques and parallel factor analysis (PARAFAC) modeling, we demonstrate that additional broadbands are sensitive to extrinsic defects, type ν-CH3, a product of decomposition of 2-propanol. The presence of C-H bonds shows the dependence with the calcination temperature and the increase of the lattice expansion coefficient until 4.7 × 10-6 K-1 resulting in the contribution to the change of band gap with the temperature ((dEg/dT)P). In this work, we correlated the electronic properties of BaTiO3 with intrinsic and extrinsic defects and elucidated the presence of additional broadbands. This approach differentiates the contributions of excitonic states and surfaces, which is necessary to understand the electronic properties of perovskite oxides.

Use of axial length to estimate the vitreous chamber volume in pseudophakic.

PURPOSE: To develop an equation for estimating the vitreous chamber volume in pseudophakic patients based on the axial length of the eye. METHODS: A consecutive series of patients who underwent vitrectomy surgery for a macular hole or an epiretinal membrane were enrolled. The inclusion criteria were as follows: having pseudophakia, being older than 50 years, and having eyes with axial length ranging from 21 to 26 mm. Before the surgery, the axial length was measured using optical biometry. Pars plan vitrectomy was performed, and, after the fluid-air exchange, the vitreous chamber was filled with Brilliant Blue G (0.005%). The infused volume of each eye was recorded. Then, epiretinal membrane peeling or internal limiting membrane peeling and a new fluid-air exchange were performed. Main outcomes and measures were the vitreous chamber volume and axial length. RESULTS: The sample consisted of 112 patients. The mean [standard deviation (SD), range] age was 71 years (7, 53-90). Sixty-five individuals (58%) were women. In 58 (51.8%) patients, surgery was performed on the right eye. The mean (SD; range) axial length was 23.78 mm (0.93; 21.55-25.26), and the mean (SD; range) vitreous chamber volume was 4.96 mL (0.69; 3.60-6.40). Pearson's correlation coefficient (r = 0.950; p < 0.01) was positive, and the coefficient of determination (R2) was 0.902. The estimated regression equation was Y = 0.71X - 11.84, where Y was the vitreous chamber volume, X was the axial length of the eye, the linear coefficient for the straight line was - 11.83, and the angular coefficient was 0.71 (p < 0.01). CONCLUSION: These data suggest that the vitreous chamber volume is significantly correlated with the axial length and the former could probably be calculated using biometry. New studies with larger samples will be required to confirm these observations and will allow the development of an algorithm (perhaps non-linear) that includes extreme axial length values and that takes into account other factors such as the status of the lens and sex.

Hydrative Aminoxylation of Ynamides: One Reaction, Two Mechanisms.

Organic synthesis boasts a wide array of reactions involving either radical species or ionic intermediates. The combination of radical and polar species, however, has not been explored to a comparable extent. Herein we present the hydrative aminoxylation of ynamides, a reaction which can proceed by either a polar-radical crossover mechanism or through a rare cationic activation. Common to both processes is the versatility of the persistent radical TEMPO and its oxidised oxoammonium derivative TEMPO+ . The unique mechanisms of these processes are elucidated experimentally and by in-depth DFT-calculations.

Studies on the Synthesis of Phlegmarine-Type Lycopodium Alkaloids: Enantioselective Synthesis of (-)-Cermizine B, (+)-Serratezomine E, and (+)-Luciduline.

The synthesis of the Lycopodium alkaloids, (-)-cermizine B, (+)-serratezomine E, and (+)-luciduline using phenylglycinol-derived tricyclic lactams as chiral scaffolds, is reported. The requisite lactams are prepared by a cyclocondensation reaction between ( R)- or ( S)-phenylglycinol and the substituted δ-keto ester 11, easily accessible from ( R)-pulegone. The factors governing the stereoselectivity of these cyclocondensation reactions are discussed. Key steps of the synthesis from the stereochemical standpoint are the stereoselective elaboration of the allyl substituent to the ( S)-2-(piperidyl)methyl moiety and the stereoselective removal of the chiral inductor to give a cis-decahydroquinoline.

A Catalytic Cross-Olefination of Diazo Compounds with Sulfoxonium Ylides.

A ruthenium-catalysed cross-olefination of diazo compounds and sulfoxonium ylides is presented. Our reaction design exploits the intrinsic difference in reactivity of diazo compounds and sulfoxonium ylides as both carbene precursors and nucleophiles, which results in a highly selective reaction.

Enantioselective synthesis of lepadins A-D from a phenylglycinol-derived hydroquinolone lactam.

The marine alkaloids (-)-lepadins A-C and (+)-lepadin D, belonging to two diastereoisomeric series, were synthesized from an (R)-phenylglycinol-derived tricyclic lactam via a common cis-decahydroquinoline intermediate. Crucial aspects of the synthesis are the stereochemical control in the assembly of the cis-decahydroquinoline platform, in the introduction of the C2 methyl and C3 hydroxy substituents, and in the generation of the C5 stereocenter.

Co-benefits, trade-offs, barriers and policies for greenhouse gas mitigation in the agriculture, forestry and other land use (AFOLU) sector.

The agriculture, forestry and other land use (AFOLU) sector is responsible for approximately 25% of anthropogenic GHG emissions mainly from deforestation and agricultural emissions from livestock, soil and nutrient management. Mitigation from the sector is thus extremely important in meeting emission reduction targets. The sector offers a variety of cost-competitive mitigation options with most analyses indicating a decline in emissions largely due to decreasing deforestation rates. Sustainability criteria are needed to guide development and implementation of AFOLU mitigation measures with particular focus on multifunctional systems that allow the delivery of multiple services from land. It is striking that almost all of the positive and negative impacts, opportunities and barriers are context specific, precluding generic statements about which AFOLU mitigation measures have the greatest promise at a global scale. This finding underlines the importance of considering each mitigation strategy on a case-by-case basis, systemic effects when implementing mitigation options on the national scale, and suggests that policies need to be flexible enough to allow such assessments. National and international agricultural and forest (climate) policies have the potential to alter the opportunity costs of specific land uses in ways that increase opportunities or barriers for attaining climate change mitigation goals. Policies governing practices in agriculture and in forest conservation and management need to account for both effective mitigation and adaptation and can help to orient practices in agriculture and in forestry towards global sharing of innovative technologies for the efficient use of land resources. Different policy instruments, especially economic incentives and regulatory approaches, are currently being applied however, for its successful implementation it is critical to understand how land-use decisions are made and how new social, political and economic forces in the future will influence this process.

Influence of the dilution method on the intraocular duration of C3F8 in vitrectomy for macular hole: a randomized clinical trial.

PURPOSE: To compare the injection of small amounts of undiluted C3F8 with the traditional gas injection in vitrectomy for macular hole treatment. METHODS: This clinical trial included 26 individuals divided into two groups. Group 1 received an intravitreal injection of 0.9-1.0 mL of 100% C3F8, and Group 2 received 15-20 mL of 20% C3F8. RESULTS: The median intraocular gas duration was 31 days in Group 1 and 34 in Group 2. The median letter gains in corrected distance visual acuity for the 26th postoperative week were 20 letters in Group 1 and 12.5 in Group 2. The median intraocular pressure was normal in both groups. Primary anatomical success was 11/13 in both groups. CONCLUSIONS: The use of C3F8 gas in a small undiluted volume is an alternative that slightly reduces the duration of the gas without negatively affecting the anatomical and visual response.

Revisiting the reaction pathways for phospholipid hydrolysis catalyzed by phospholipase A2 with QM/MM methods.

Secreted phospholipase A2 (sPLA2) is a Ca2+-dependent, widely distributed enzyme superfamily in almost all mammalian tissues and bacteria. It is also a critical component of the venom of nearly all snakes, as well as many invertebrate species. In non-venomous contexts, sPLA2 assumes significance in cellular signaling pathways by binding cell membranes and catalyzing ester bond hydrolysis at the sn-2 position of phospholipids. Elevated levels of GIIA sPLA2 have been detected in the synovial fluid of arthritis patients, where it exhibits a pro-inflammatory function. Consequently, identifying sPLA2 inhibitors holds promise for creating highly effective pharmaceutical treatments. Beyond arthritis, the similarities among GIIA sPLA2s offer an opportunity for developing treatments against snakebite envenoming, the deadliest neglected tropical disease. Despite decades of study, the details of PLA2 membrane-binding, substrate-binding, and reaction mechanism remain elusive, demanding a comprehensive understanding of the sPLA2 catalytic mechanism. This study explores two reaction mechanism hypotheses, involving one or two water molecules, and distinct roles for the Ca2+ cofactor. Our research focuses on the human synovial sPLA2 enzyme bound to lipid bilayers of varying phospholipid compositions, and employing adiabatic QM/MM and QM/MM MD umbrella sampling methods to energetically and geometrically characterize the structures found along both reaction pathways. Our studies demonstrate the higher frequency of productive conformations within the single-water pathway, also revealing a lower free energy barrier for hydrolyzing POPC. Furthermore, we observe that the TS of this concerted one-step reaction closely resembles transition state geometries observed in X-ray crystallography complexes featuring high-affinity transition state analogue inhibitors.

Development of Nanoscale Graphene Oxide Models for the Adsorption of Biological Molecules.

Graphene oxide (GO), a nanomaterial with promising applications that range from water purification to enzyme immobilization, is actively present in scientific research since its discovery. GO studies with computational methodologies such as molecular dynamics are frequently reported in the literature; however, the models used often rely on approximations, such as randomly placing functional groups and the use of generalized force fields. Therefore, it is important to develop new MD models that provide a more accurate description of GO structures and their interaction with an aqueous solvent and other adsorbate molecules. In this paper, we derived new force field non-bonded parameters from linear-scaling density functional theory calculations of nanoscale GO sheets with more than 10,000 atoms through an atoms-in-molecules (AIM) partitioning scheme. The resulting GAFF2-AIM force field, derived from the bonded terms of GAFF2 parameterization, reproduces the solvent structure reported in ab initio MD simulations better than the force field nowadays widely used in the literature. Additionally, we analyzed the effect of the ionic strength of the medium and of the C/O ratio on the distribution of charges surrounding the GO sheets. Finally, we simulated the adsorption of natural amino acid molecules to a GO sheet and estimated their free energy of binding, which compared very favorably to their respective experimental values, validating the force field presented in this work.

Guidelines for integrating spirituality into the prevention and treatment of alcohol and other substance use disorders.

Alcohol and other substance use disorders are complex problems with multiple variables and determinants, requiring a multidimensional approach to prevention and treatment. A robust body of research shows that religiosity and spirituality (R/S) play a prominent role in these disorders; however, how to apply this knowledge remains unclear. We present practical guidelines on how to integrate R/S into substance use prevention and treatment in an ethical, evidence-based manner. These guidelines have been endorsed by prominent academic leaders in these topics and by health associations affiliated with the three major Brazilian religions. The integration of R/S is part of a respectful, person-centered, interdisciplinary approach, which imposes neither religious beliefs nor secular worldviews. The most critical interventions include collecting a history of spiritual and religious beliefs, practices, and experiences and evaluating how these may be used positively in treatment. It is also essential that health professionals are encouraged to value and respect the R/S of patients, and that religious groups recognize that professional and technical interventions can make a valuable contribution to preventing and treating these disorders.

Modification of Cellulose Acetate Microfiltration Membranes Using Graphene Oxide-Polyethyleneimine for Enhanced Dye Rejection.

Pressure-based membrane processes represent excellent water resource recovery prospects from industrial waste streams. In contrast with conventional pretreatment technologies, studies have shown that membrane pretreatment applications, such as microfiltration (MF), are more cost-effective and improve the results of the overall treatment processes. Hence, enhancing rejection efficiency of MF will enhance the performance of any downstream treatment processes. In this study, 0.45 µm cellulose acetate (CA) microfiltration membranes were modified by vacuum filtration-assisted layer-by-layer deposition of bilayers composed of negatively charged graphene oxide (GO) and positively charged polyethyleneimine (PEI). The performance of 1-, 2-, and 4-bilayer GO-PEI-modified membranes were investigated for their dye-rejection of anionic eriochrome black T (EBT) dye and cationic methylene blue (MB) dye in a cross-flow membrane module. As the number of bilayers on the membrane increased, the membrane thicknesses increased, and the deionized (DI) water flux through the membranes decreased from 4877 LMH/bar for the control (no bilayer) membrane to 2890 LMH/bar for the 4-bilayer membrane. Conversely, the dye-rejection performance of the modified membranes increased as increasing bilayers of GO-PEI deposited on the membranes. The anionic EBT dye saw superior rejection (~90% rejection) compared to the cationic MB dye (~80% rejection), which can be attributable to the electrostatic repulsion between the negatively charged GO surface and anionic EBT dye. After 50% recovery of the saline and dye-laden feed water, there was an observed drop in DI water fluxes of ~40-41% and 36%, respectively. There was also a slight increase in EBT dye-rejection during the composite feed-water experiments, attributed to the precipitation of salts on the membrane feed side or pore spaces, which subsequently reduce the membrane pore sizes.

Total Synthesis of (-)-Cylindricine H.

Starting from (R)-phenylglycinol-derived tricyclic lactam 1, the enantioselective synthesis of (-)-cylindricine H is reported. From the stereochemical standpoint, the key steps are the stereoselective generation of the quaternary C10 stereocenter, the stereoselective introduction of the C4 acetoxy and C2 butyl substituents taking advantage of the lactam carbonyl functionality, and the assembly of the pyrrolidine ring with the required functionalized one-carbon chain at C13 by intramolecular opening of an epoxide.

Imaging mitochondrial calcium dynamics in the central nervous system.

Mitochondrial calcium handling is a particularly active research area in the neuroscience field, as it plays key roles in the regulation of several functions of the central nervous system, such as synaptic transmission and plasticity, astrocyte calcium signaling, neuronal activity… In the last few decades, a panel of techniques have been developed to measure mitochondrial calcium dynamics, relying mostly on photonic microscopy, and including synthetic sensors, hybrid sensors and genetically encoded calcium sensors. The goal of this review is to endow the reader with a deep knowledge of the historical and latest tools to monitor mitochondrial calcium events in the brain, as well as a comprehensive overview of the current state of the art in brain mitochondrial calcium signaling. We will discuss the main calcium probes used in the field, their mitochondrial targeting strategies, their key properties and major drawbacks. In addition, we will detail the main roles of mitochondrial calcium handling in neuronal tissues through an extended report of the recent studies using mitochondrial targeted calcium sensors in neuronal and astroglial cells, in vitro and in vivo.

Stroke and Respiratory Failure: Mind the Shunt!

When stroke patients present with respiratory failure, the first thought that clinicians have is that it is probably related to aspiration pneumonia. However, other causes should be considered, such as intracardiac or intrapulmonary shunts, that could present with paradoxical embolism. Paradoxical embolism is a rare entity defined by the occurrence of a venous thrombotic event associated with a systemic arterial embolism. Frequently, paradoxical embolism presents with platypnoea-orthodeoxia syndrome. Platypnoea-orthodeoxia syndrome is uncommon and is characterized by dyspnoea and hypoxaemia induced by orthostatic position, where symptoms and oxygenation are relieved by recumbency. The authors report a case of a patient who presented with an ischaemic stroke and progression to platypnoea-orthodeoxia syndrome with documentation of simultaneous pulmonary embolism and pulmonary arteriovenous malformations. LEARNING POINTS: There are other causes to explain simultaneous presentation of stroke and respiratory failure, which should be kept in mind.The association between arterial and venous thrombosis; be aware of paradoxical embolism and search for intracardiac or intrapulmonary shunts.Platypnoea-orthodeoxia syndrome is characterized by dyspnoea and hypoxaemia induced by orthostatic position and relieved by recumbency; it is a red flag to think of an intracardiac or intrapulmonary shunt.

Taxus baccata intoxication: the sun after the electrical storm. / Intoxicação por Taxus baccata: sol após a tempestade elétrica.

European yew (Taxus baccata) is a tree with alternate branchlets, green needles and reddish-brown bark. A high-dose ingestion of Taxus baccata for suicidal purposes usually results in death. The systemic toxicity is mainly cardiac. The authors describe the case of a young patient who ingested a high dose of yew needles and presented to the emergency department with a serious intoxication, which manifested as a chaotic malignant arrhythmia that was successfully treated after exhaustive supportive care.

O teixo europeu (Taxus baccata) é uma árvore com pequenos ramos alternados, agulhas verdes e casca marrom-avermelhada. A ingestão de uma alta dose de Taxus baccata com intenção suicida geralmente resulta em morte. A toxicidade sistêmica é principalmente cardíaca. Os autores descrevem o caso de uma jovem paciente que ingeriu uma alta dose de agulhas de teixo e foi trazida ao pronto-socorro com intoxicação grave, manifestada por arritmias malignas caóticas, tratadas com sucesso após exaustivos cuidados de suporte.