A Modified Fokker-Planck Approach for a Complete Description of Vibrational Kinetics in a N2 Plasma Chemistry Model.

The Fokker-Planck (FP) approach for the description of vibrational kinetics is extended in order to include multiquanta transitions and time dependent solutions. Due to the importance of vibrational ladder climbing for the optimization of plasma-assisted nitrogen fixation, nitrogen is used as a test case with a comprehensive set of elementary processes affecting the vibrational distribution function (VDF). The inclusion of the vibrational energy equation is shown to be the best way to model transient conditions in a plasma reactor using the FP approach. Results are benchmarked against results from the widely employed state-to-state (STS) approach for a wide parameters range. STS and FP solutions agree within ∼10% for the lowest vibrational levels, while time dependent VDFs are in agreement with the STS solution within a ∼ 5% error. Using the FP approach offers the possibility to parametrize drift and diffusion coefficients in energy space as a function of vibrational and gas temperature, providing intuitive and immediate insights into energy transport within the vibrational manifold.

Impact of serum albumin concentration and neutrophil-lymphocyte ratio score on gastric cancer prognosis.

INTRODUCTION/AIM: Serum albumin concentration (COA) and neutrophil-lymphocyte ratio (NLR) could reflect immunological and nutritional status. We aim to evaluate the impact of COA-NLR score on the prognosis of gastric cancer (GC). MATERIAL AND METHODS: We perform a retrospective analysis on a database of 637 GC cases, between January 2010 and December 2017. In 396 patients, the inclusion criteria for this study were met (non-resectional or palliative surgery were excluded). Analytic data was only available in 203 patients. COA-NLR score was defined as follows: COA under 35 g/L and NLR value of 2.585 or higher, score 2; one of these conditions, score 1; and neither, score 0. RESULTS: In our population (n = 203), 87 patients were classified as score 0, 82 as score 1 and 34 as score 2. COA-NLR score was significantly associated with DFS (HR 1.674; CI 95% 1.115-2.513; p = 0.013) and with OS (HR 2.072; CI 95% 1.531-2.805; p < 0.001). Kaplan-Meier curve analysis (log rank test) revealed that a higher score of COA-NLR predicted a worse OS (p < 0.001) and DFS (p = 0.03). COA-NLR was an independent prognostic factor for OS when adjusted to pStage and age (adjusted HR 1.566; CI 95% 1.145-2.143; p = 0.005). CONCLUSIONS: Preoperative COA-NLR score was significantly associated with worse OS and DFS and, in this way, with worse prognosis on GC patients submitted to curative-intent resectional surgery.

Embryonic stem cells neural differentiation qualifies the role of Wnt/ß-Catenin signals in human telencephalic specification and regionalization.

Wnt-ligands are among key morphogens that mediate patterning of the anterior territories of the developing brain in mammals. We qualified the role of Wnt-signals in regional specification and subregional organization of the human telencephalon using human pluripotent stem cells (hPSCs). One step neural conversion of hPSCs using SMAD inhibitors leads to progenitors with a default rostral identity. It provides an ideal biological substrate for investigating the role of Wnt signaling in both anteroposterior and dorso-ventral processes. Challenging hPSC-neural derivatives with Wnt-antagonists, alone or combined with sonic hedgehog (Shh), we found that Wnt-inhibition promote both telencephalic specification and ventral patterning of telencephalic neural precursors in a dose-dependent manner. Using optimal Wnt-antagonist and Shh-agonist signals we produced human ventral-telencephalic precursors, committed to differentiation into striatal projection neurons both in vitro and in vivo after homotypic transplantation in quinolinate-lesioned rats. This study indicates that sequentially organized Wnt-signals play a key role in the development of human ventral telencephalic territories from which the striatum arise. In addition, the optimized production of hPSC-derived striatal cells described here offers a relevant biological resource for exploring and curing Huntington disease.

High throughput screening for inhibitors of REST in neural derivatives of human embryonic stem cells reveals a chemical compound that promotes expression of neuronal genes.

Decreased expression of neuronal genes such as brain-derived neurotrophic factor (BDNF) is associated with several neurological disorders. One molecular mechanism associated with Huntington disease (HD) is a discrete increase in the nuclear activity of the transcriptional repressor REST/NRSF binding to repressor element-1 (RE1) sequences. High-throughput screening of a library of 6,984 compounds with luciferase-assay measuring REST activity in neural derivatives of human embryonic stem cells led to identify two benzoimidazole-5-carboxamide derivatives that inhibited REST silencing in a RE1-dependent manner. The most potent compound, X5050, targeted REST degradation, but neither REST expression, RNA splicing nor binding to RE1 sequence. Differential transcriptomic analysis revealed the upregulation of neuronal genes targeted by REST in wild-type neural cells treated with X5050. This activity was confirmed in neural cells produced from human induced pluripotent stem cells derived from a HD patient. Acute intraventricular delivery of X5050 increased the expressions of BDNF and several other REST-regulated genes in the prefrontal cortex of mice with quinolinate-induced striatal lesions. This study demonstrates that the use of pluripotent stem cell derivatives can represent a crucial step toward the identification of pharmacological compounds with therapeutic potential in neurological affections involving decreased expression of neuronal genes associated to increased REST activity, such as Huntington disease.

ERS International Congress 2023: highlights from the Respiratory Intensive Care Assembly.

Early career members of Assembly 2 (Respiratory Intensive Care) attended the 2023 European Respiratory Society International Congress in Milan, Italy. The conference covered acute and chronic respiratory failure. Sessions of interest to our assembly members and to those interested in respiratory critical care are summarised in this article and include the latest updates in respiratory intensive care, in particular acute respiratory distress syndrome and mechanical ventilation.

Highlights from the Respiratory Failure and Mechanical Ventilation 2022 Conference.

The Respiratory Intensive Care Assembly of the European Respiratory Society gathered in Berlin to organise the second Respiratory Failure and Mechanical Ventilation Conference in June 2022. The conference covered several key points of acute and chronic respiratory failure in adults. During the 3-day conference, ventilatory strategies, patient selection, diagnostic approaches, treatment and health-related quality of life topics were addressed by a panel of international experts. Lectures delivered during the event have been summarised by Early Career Members of the Assembly and take-home messages highlighted.

Osmoregulatory and Antioxidants Modulation by Salicylic Acid and Methionine in Cowpea Plants under the Water Restriction.

Global climate changes have intensified water stress in arid and semi-arid regions, reducing plant growth and yield. In this scenario, the present study aimed to evaluate the mitigating action of salicylic acid and methionine in cowpea cultivars under water restriction conditions. An experiment was conducted in a completely randomized design with treatments set up in a 2 × 5 factorial arrangement corresponding to two cowpea cultivars (BRS Novaera and BRS Pajeú) and five treatments of water replenishment, salicylic acid, and methionine. After eight days, water stress decreased the Ψw, leaf area, and fresh mass and increased the total soluble sugars and catalase activity in the two cultivars. After sixteen days, water stress increased the activity of the superoxide dismutase and ascorbate peroxidase enzymes and decreased the total soluble sugars content and catalase activity of BRS Pajeú plants. This stress response was intensified in the BRS Pajeú plants sprayed with salicylic acid and the BRS Novaera plants with salicylic acid or methionine. BRS Pajeú is more tolerant to water stress than BRS Novaera; therefore, the regulations induced by the isolated application of salicylic acid and methionine were more intense in BRS Novaera, stimulating the tolerance mechanism of this cultivar to water stress.

Quantification of surface charging memory effect in ionization wave dynamics.

The dynamics of ionization waves (IWs) in atmospheric pressure discharges is fundamentally determined by the electric polarity (positive or negative) at which they are generated and by the presence of memory effects, i.e. leftover charges and reactive species that influence subsequent IWs. This work examines and compares positive and negative IWs in pulsed plasma jets (1 [Formula: see text]s on-time), showing the difference in their nature and the different resulting interaction with a dielectric BSO target. For the first time, it is shown that a surface charging memory effect is produced, i.e. that a significant amount of surface charges and electric field remain in the target in between discharge pulses (200 [Formula: see text]s off-time). This memory effect directly impacts IW dynamics and is especially important when using negative electric polarity. The results suggest that the remainder of surface charges is due to the lack of charged particles in the plasma near the target, which avoids a full neutralization of the target. This demonstration and the quantification of the memory effect are possible for the first time by using an unique approach, assessing the electric field inside a dielectric material through the combination of an advanced experimental technique called Mueller polarimetry and state-of-the-art numerical simulations.

Allelopathy of Ricinus communis and light spectrum variation decrease emergence and growth of Cyperus rotundus

Weeds negatively influence agricultural production. However, those losses depend on weed specie, its time of emergence, and period of interference on agricultural crops. Synthetic herbicides are commonly used to control these plants species; however, they may cause damage to the environment, human beings and animals health, and this problem justify the need to develop alternative bioherbicides. To evaluate the allelopathic potential of Ricinus communis (Castor bean) and light spectrum variation on the emergence and growth of Cyperus rotundus L., a trial was carried out in a protected environment with 15% of brightness reduction at the Center for Agricultural and Environmental Sciences at the Paraíba State University. Four aqueous extract concentrations of R. communis leaves were tested (0, 5, 10, and 15%) and four light spectrums variations (white, purple, blue, and red lights). Variables such as emergence, length, dry matter accumulation and growth rates of shoots and root of C. rotundus seedlings were assessed. Data were analyzed by normality test, analysis of variance, polynomial regression, and averages test. Soot and root emergence, length, and dry matter accumulation of C. rotundus seedlings were reduced due to the allelopathy caused by R. communis aqueous extract leaves (15% concentration) and under purple or red light spectrum radiation.

[Functions of prion protein PrPc]. / Fonctions de la protéine prion PrPc.

It is now well established that both normal and pathological (or scrapie) isoforms of prion protein, PrPc and PrPsc respectively, are involved in the development and progression of various forms of neurodegenerative diseases, including scrapie in sheep, bovine spongiform encephalopathy (or "mad cow disease") and Creutzfeldt-Jakob disease in human, collectively known as prion diseases. The protein PrPc is highly expressed in the central nervous system in neurons and glial cells, and also present in non-brain cells, such as immune cells or epithelial and endothelial cells. Identification of the physiological functions of PrPc in these different cell types thus appears crucial for understanding the progression of prion diseases. Recent studies highlighted several major roles for PrPc that may be considered in two major domains : (1) cell survival (protection against oxidative stress and apoptosis) and (2) cell adhesion. In association with cell adhesion, distinct functions of PrPc were observed, depending on cell types : neuronal differentiation, epithelial and endothelial barrier integrity, transendothelial migration of monocytes, T cell activation. These observations suggest that PrPc functions may be particularly relevant to cellular stress, as well as inflammatory or infectious situations.

Physiology and yield of piel de sapo melon (Cucumis melo L. ) under water deficit in semi-arid region, Brazil / Fisiologia e rendimento do meloeiro pele-de-sapo (Cucumis melo L. ) cultivado sob diferentes regimes hídricos em região semi-árida, Brasil

Melon (Cucumis melo L.) is a crop of great socioeconomic importance in regions with semiarid climate, as found in Northeast Brazil. In this region water deficit is a usual condition as well as the main reduction factor of plant productivity. Due to this phenomenon, irrigation techniques are used to make available the amount of water needed for plant production. Therefore, this study evaluated the physiology and fruit production changes of 'Juazeiro' Piel de sapo melon plants under different water replacement rates. 'Juazeiro' melon was grown under four reference evapotranspiration replacement rates (40, 60, 80 and 100% of ETo) distributed randomly in blocks with 5 replicates. The plants were cultivated in the field, in an experimental area located in the Brazilian Northeast region, under hot and dry semiarid climatic conditions, and during the growing cycle the 'Juazeiro' hybrid melon plants were evaluated for leaf area, biomass accumulation, gas exchange, photochemical efficiency of photosystem PSII and production of fruits per plant. Application of water replacement rates of 100% ETo leads to highest growth, net photosynthesis, and fruit yield of 'Juazeiro' melon. Water replacement at 80% ETo can be used for 'Juazeiro" melon under semiarid climatic conditions, but with small losses in fruit yield. Water replacement below 80% ETo leads to drastic reductions in growth, gas exchanges, quantum efficiency of photosystem II and fruit yield, which impairs melon production in semi-arid climate environments. KEYWORDS: Fruits yield. Gas exchange. Photochemical efficiency. INTRODUCTION Melon (Cucumis melo L.) is an important socioeconomic fruit cultivated in the world. Melon fruit production was 29.6 million tons and this production is distributed among China, Turkey, Iran, Egypt, India, United States, and Brazil. These countries account for 70% of the world production (FAO, 2017). In Brazil, cultivated area exceeded 22.000 ha with more than 521.6 thousand tons in 2015. 94.7% of this production was obtained in the semi-arid region of Northeast, mainly in the states of Ceará and Rio Grande do Norte, the largest producers in the country (IBGE, 2014). However, especially due to irregular rainfall, melon fruit production has been dropping in the last few years in this region. According to Pereira Filho et al. (2015), melon plants growth, development, and fruit production are greatly affected by climate conditions, mainly by water stress. Water stress is one of the most complex physiological phenomena because it is a multidimensional component which can considerably limit agricultural crops growth and development (DOGAN et al., 2008; LISAR et al., 2012; SILVA et al., 2015), generally in arid and semi-arid regions, such as in Northeast Brazil. Moreover, plant adaptability to water deficit conditions is related to a range of events occurring at several levels (LISAR et al., 2012), observed as a physiological, biochemical, and molecular adaptations, among others. At plant physiological level, soil water deficit has a significant effect on gas exchange, because it is a result of the limitation of stomatal conductance, and it is considered the primary cause of photosynthetic inhibition due to CO2 influx limitation, as well as water efflux from transpiration Received: 08/04/19 Accepted: 20/12/19

O meloeiro (Cucumis melo L.) é uma cultura de grande importância social e econômica mundial, principalmente em regiões de clima semiárido como o Nordeste brasileiro, onde déficit hídrico é condição comum e considerado o principal fator de redução da produtividade das plantas. Tal fenômeno força a utilização da irrigação como forma de disponibilizar a quantidade de água necessária à produção. Assim, objetivou-se com este trabalho avaliar as variações fisiológicas e produtivas de meloeiro pele-de-sapo submetidos a diferentes taxas de reposição hídrica. O híbrido 'Juazeiro' de melão pele-de-sapo foi cultivado sob quatro taxas de reposição da evapotranspiração de referência (40, 60, 80 e 100% da ETo), distribuídas em blocos ao acaso com 5 repetições. As plantas foram cultivadas em campo, em área experimental situada no Nordeste brasileiro, em condições clima semiárido quente e seco, e durante o ciclo de cultivo as plantas de meloeiro híbrido 'Juazeiro' foram avaliadas quanto a área foliar, o acúmulo de biomassa, as trocas gasosas, eficiência fotoquímica do fotossitesma PSII e produção de frutos por planta. A aplicação de taxas de reposição hídrica a 100% da ETo proporciona o maior crescimento, fotossíntese liquida e produção do meloeiro 'Juazeiro'. A reposição hídrica a 80% da ETo pode ser usada para o cultivo do meloeiro 'Juazeiro' em condições de clima semiárido, admitindo-se pequenas perdas no rendimento. A reposição hídrica com lâminas inferiores a 80% da ETo promove reduções drásticas no crescimento, trocas gasosas, eficiência quântica do fotossistema II e produção, que inviabilizam a produção do meloeiro em ambientes de clima semiáridos.

Derivation of striatal neurons from human stem cells.

Huntington's disease cell therapy is for the moment the only therapeutic approach for this devastating neurodegenerative disorder that has demonstrated significant and long-lasting functional benefits in patient. Logistical and biological difficulties associated with the use of human fetal tissue however dramatically reduce the number of patients eligible to this therapy. During the past decade, the exploration of alternative cellular sources, conducted in parallel to the clinical trials, has gradually put forward human pluripotent stem cells as prime candidate for Huntington's disease cell therapy. Protocols for the differentiation of such cells into therapeutically relevant striatal neuron precursors require thorough understanding of the molecular determinant that controls the development of the anterior and ventral part of the forebrain from which the striatum arises. Key secreted molecules that play pivotal roles in the development of these regions in mice have been successfully used to direct the specification of neural derivatives of human pluripotent stem cells. Assessment of the therapeutic potential of resulting striatal grafts has made significant progress in the last 4 years. The proof of principle that human embryonic stem cell derivatives can achieve some degrees of functional striatal repair in a mouse model of Huntington's disease is now established. As in other neurodegenerative diseases such as Parkinson's disease, recent developments have raised hopes for stem cell-based therapy of Huntington's disease.

Bioremediation potential of filamentous fungi in methylene blue: Solid and liquid culture media / Potencial de biorremediação de fungos filamentoso em azul de metileno: Meio sólido e líquido

ABSTRACT The evaluation of the bioremediation potential of microbial with dyes in solid and liquid culture media has been described, but prior studies have not mentioned which culture method is most appropriate for selection of microorganisms. Therefore, the aim of this work was to evaluate the bioremediation potential of filamentous fungi in liquid and solid culture media with methylene blue. The fungi isolates tested were Pleurotus ostreatoroseus (POR-SP1, POR-SP2), P. ostreatus (DF39, EF58 and EF60), Pycnoporus sanguineus (PS) and Fusidium sp. (FUS). The methylene blue concentrations tested were 0, 5, 10, and 50 mg L-1 in the solid medium and 0, 5, 25, 50, and 100 mg L-1 in the liquid medium. In the solid medium, the mycelial diameters of DF39, EF58, FUS, and PS were not influenced by the increase in dye concentration. In the liquid medium, DF39, EF58, EF60, and FUS showed a constant methylene blue degradation rate with increasing dye concentration. The dye degradation rate was correlated with the pH of the liquid medium for EF58, EF60, and FUS. The lower diameter growth in the solid medium did not influence the methylene blue dye degradation rate in the liquid medium.

RESUMO A avaliação do potencial biorremediador microbiano com corantes é descrita em meio de cultura sólido e líquido, mas não é mencionado qual método de cultivo é o mais apropriado na seleção de microrganismos. Para tanto, o objetivo deste trabalho foi avaliar o potencial de biorremediação de fungos filamentosos, em meios de cultura líquido e sólido com azul de metileno. Os isolados fúngicos testados foram: Pleurotus ostreatoroseus (POR-SP1 e POR-SP2), P. ostreatus (DF39, EF58 e EF60), Pycnoporus sanguineus (PS) e Fusidium sp. (FUS). As concentrações de azul de metileno testadas foram 0, 5, 10 e 50 mg L-1 em meio sólido e de 0, 5, 25, 50 e 100 mg L-1 em meio líquido. No meio sólido, o diâmetro micelial de DF39, EF58, FUS e PS não foi influenciado pelo aumento da concentração de corante. Em meio líquido, DF39, EF58, EF60 e FUS apresentaram degradação do azul de metileno constante com o aumento da concentração do corante. A taxa de degradação do corante foi correlacionada com o pH do meio líquido, para EF58, EF60 e FUS. O menor crescimento, em diâmetro, em meio sólido, não influenciou na taxa de degradação do corante azul de metileno, em meio líquido.

Human pluripotent stem cell therapy for Huntington's disease: technical, immunological, and safety challenges human pluripotent stem cell therapy for Huntington's disease: technical, immunological, and safety challenges.

Intra-striatal transplantation of homotypic fetal tissue at the time of peak striatal neurogenesis can provide some functional benefit to patients suffering from Huntington's disease. Currently, the only approach shown to slow down the course of this condition is replacement of the neurons primarily targeted in this disorder, although it has been transient and has only worked with a limited number of patients. Otherwise, this dominantly inherited neurodegenerative disease inevitably results in the progressive decline of motricity, cognition, and behavior, and leads to death within 15 to 20 years of onset. However, fetal neural cell therapy of Huntington's disease, as with a similar approach in Parkinson's disease, is marred with both technical and biological hurdles related to the source of grafting material. This heavily restricts the number of patients who can be treated. A substitute cell source is therefore needed, but must perform at least as well as fetal neural graft in terms of brain recovery and reconstruction, while overcoming its major obstacles. Human pluripotent stem cells (embryonic in origin or induced from adult cells through genetic reprogramming) have the potential to meet those challenges. In this review, the therapeutic potential in view of 4 major issues is identified during fetal cell therapy clinical trials: 1) logistics of graft procurement, 2) quality control of the cell preparation, 3) immunogenicity of the graft, and 4) safety of the procedure.

Produtividade da palma forrageira cultivada em diferentes densidades de plantio / Cactus pear forage production under different plant densities

Entre as práticas e técnicas empregadas para obtenção de maior produtividade de massa seca, a escolha do arranjamento de plantas é, entre as decisões de manejo das plantas cultivadas, uma das mais importantes, associada à escolha da cultivar e do sistema de cultivo. Em função do exposto, objetivou-se com este trabalho avaliar a produtividade de forragem de palma forrageira cultivada em diferentes densidades de plantio. O experimento foi instalado no Campo Experimental do CPATC - Embrapa, em Frei Paulo - SE. O delineamento experimental utilizado foi em blocos casualizados, com parcelas subdivididas e quatro repetições. As parcelas foram representadas por genótipos de palma forrageira (Miúda, Redonda e Gigante) e as subparcelas pelas seguintes densidades de plantio (10.000, 20.000, 40.000 e 80.000 plantas ha-1). Os genótipos de palma forrageira apresentam comportamento diferente quanto ao número de cladódios na 1a inserção e no número de cladódios por planta. O aumento da densidade de plantio reduz o comprimento e a largura do cladódio. Existe comportamento diferencial dos genótipos quanto à capacidade produtiva em diferentes densidades. A palma forrageira Miúda apresenta melhor potencial produtivo no cultivo adensado. Já a palma Redonda e Gigante tem maior teor de umidade na massa verde da forragem, e, em cultivo adensado, a palma forrageira reduz a massa verde e seca por planta.

Plant arrangement is one of the most important among management decisions of cultivated plants among the practices and techniques employed to obtain higher productivity of dry matter, due to its association to cultivar choice and cultivation system. The current research evaluates forage yield at different planting densities. The experiment was conducted in the CPATC-Embrapa experimental field in the municipality of Frei Paulo SE Brazil. Experimental design consisted of randomized blocks with split plot and four replications. The plots were the genotypes of forage cactus (small, rounded and giant size) and subplots followed planting densities (10,000; 20,000; 40,000 and 80,000 plants ha-1). Cactus forage genotypes exhibit different behavior with regard to number of cladodes in the first insertion and in the number of cladodes per plant. Increased planting density reduces the cladodes length and width. A differential behavior of genotypes exists with regard to the yield capacity for different densities. The small forager cactus has the best production potential in dense growth, whereas the round and giant-sized cactus have a higher rate of humidity in green mass. Forager cactus reduces green and dry mass per plant in dense culture.

Junctional expression of the prion protein PrPC by brain endothelial cells: a role in trans-endothelial migration of human monocytes.

The conversion of prion protein (PrP(C)) to its protease-resistant isoform is involved in the pathogenesis of prion diseases. Although PrP(C) is highly expressed in neurons and other cell types, its physiological function still remains elusive. Here, we describe how we evaluated its expression, subcellular localization and putative function in brain endothelial cells, which constitute the blood-brain barrier. We detected its expression in microvascular endothelium in mouse brain sections and at intercellular junctions of freshly isolated brain microvessels and cultured brain endothelial cells of mouse, rat and human origin. PrP(C) co-localized with the adhesion molecule platelet endothelial cell adhesion molecule-1 (PECAM-1); moreover, both PrP(C) and PECAM-1 were present in raft membrane microdomains. Using mixed cultures of wild-type and PrP(C)-deficient mouse brain endothelial cells, we observed that PrP(C) accumulation at cell-cell contacts was probably dependent on homophilic interactions between adjacent cells. Moreover, we report that anti-PrP(C) antibodies unexpectedly inhibited transmigration of U937 human monocytic cells as well as freshly isolated monocytes through human brain endothelial cells. Significant inhibition was observed with various anti-PrP(C) antibodies or blocking anti-PECAM-1 antibodies as control. Our results strongly support the conclusion that PrP(C) is expressed by brain endothelium as a junctional protein that is involved in the trans-endothelial migration of monocytes.

Aspectos técnicos e econômicos da bananeira 'Prata-Anã' sob fertirrigação nos tabuleiros costeiros de Sergipe / Technical and economical aspects of the banana tree "Prata-Anã" under fertirrigation in the coastal tablelands of Sergipe

Neste trabalho, objetivou-se estudar os efeitos de doses de nitrogênio e potássio via água de irrigação, sobre o tempo de colheita, componentes da produção: número de pencas, número de frutos pencas-1, número de frutos cacho-1 e massa do cacho planta-1, e lucratividade da bananeira Prata-Anã em tabuleiros costeiros do Estado de Sergipe. O experimento foi conduzido no campo, utilizando um arranjo fatorial 4x4 com quatro blocos casualizados, na Estação Experimental da Universidade Federal de Sergipe. Foram testados dois fatores: nitrogênio (0; 350; 700 e 1050, em kg ha-1 de N, na forma de uréia) e potássio (0; 400; 800 e 1200, em kg ha-1 de K2O, na forma de cloreto de potássio). O primeiro ciclo da bananeira 'Prata-Anã' é prolongado em situações de deficiências de N e K. O maior rendimento do cacho (32,56t ha-1) é obtido com a aplicação de 1050kg ha-1 ano-1 de N e 1112kg ha-1 ano-1 de K2O, cujas doses proporcionam uma lucratividade de 27,75 por cento e uma redução do custo de produção de 40,54 por cento.

The objective of the work was to study the effects of doses of N and K applied through irrigation water, on the number of days between planting and harvesting, yield components (number of hands, number of fruits per hands, number of fruits per bunch, bunch weight per plant) and the profitability of the 'Prata-Anã' banana, in the coastal tablelands of Sergipe State. The experiment was carried out in the field at the Sergipe Federal University Experimental Station. A 4² factorial in a randomized block experimental design was used. Treatments were nitrogen (0; 350; 700 e 1050, kg ha-1 of N, as urea) and potassium (0; 400; 800 e 1200, kg ha-1 of K2O, as potassium chloride). Nitrogen and potassium deficiencies increased the number of days between planting and harvesting in the first cycle. Maximum yield of 32.56 t ha-1 was associated with 1050 kg ha-1 year-1 of N and 1112kg ha-1 year -1 of K2O. These doses were able to increase net income by 27.75 percent and reduced costs by 40.54 percent.

Thymidine analogue reverse transcriptase inhibitors resistance mutations profiles and association to other nucleoside reverse transcriptase inhibitors resistance mutations observed in the context of virological failure.

During ZDV or d4T exposure, mutations at codons 41, 67, 70, 210, 215, and 219 can be selected and were named thymidine analogue mutations (TAMs). Some previous results suggested that different TAMs patterns could exist and that the kind of TAMs pattern could influence the virological response to some nucleoside reverse transcriptase inhibitors (NRTIs). In order to get more data about the relative prevalence of these patterns, their associations with other NRTI resistance mutations and the identification of the different stages observed during the acquisition of TAMs under treatment by NRTIs, we collected 1,098 RT sequences harbouring at least one TAM from patients failing to antiretroviral regimen. Sequences were stored in a database designed specifically to allow the retrieval of sequences that met specific criteria such as the occurrence and frequency of a particular mutation, the nature and frequency of the amino acid substitution at a given codon, and/or the rate of association between resistance mutations. Two pathways of TAMs can be identified: profile #1 (T215Y mutation linked) and profile # 2 (T215F mutation linked). The frequency of selection of profile # 1 is two times higher than profile # 2. The E44D/A + V118I complex, 69 insertions, and L74V mutation are associated to profile #1, whereas the Q151M complex and M184V mutation are associated to both profiles. As some NRTI resistance mutations were associated preferentially with profile #1, further studies are needed to explore if, the weaker efficacy observed on viruses harbouring this profile using some NRTIs, could be explained by the TAMs profile itself or the other associated NRTI resistance mutations.

Desenvolvimento vegetativo, rendimento da fruta e otimizacão do abacaxizeiro cv. Pérola em diferentes níveis de irrigacão / Vegetative development, fruits yield and optimization of pineapple cv. Pérola with different levels of irrigation

Apesar de ser uma planta com necessidades hídricas relativamente baixas, o abacaxizeiro tem demanda permanente de água, variável ao longo do ciclo e dependente do seu estádio de desenvolvimento. Assim, objetivou-se analisar volumes de irrigacão no desenvolvimento vegetativo, no rendimento da fruta e na otimizacão do abacaxizeiro cv. Pérola. O experimento foi realizado na Universidade Federal de Sergipe, município de São Cristóvão (11º01'S, 37º12'W), no delineamento em blocos ao acaso, com quatro tratamentos (lâminas de água) (100 por cento da evaporacão do tanque Classe A (523,7mm ano-1); 75 por cento da evaporacão do tanque Classe A (392,8mm ano-1), 50 por cento da evaporacão do tanque Classe A (261,8mm ano-1) e 0 por cento da evaporacão do tanque Classe A, seis repeticões e 12 plantas úteis por parcela. O sistema de irrigacão foi por aspersão convencional disposto em linha, com pressão de 20mca e vazão de 1,33m3 h-1. A área foliar (cmy) mínima atingida de 4552,6cmy foi observada no volume de água de 122,9mm ano-1, enquanto a massa seca das folhas (147,6g) foi constatada com 17mm ano-1. O máximo comprimento da folha D (88,9cm) foi estimado com 532,7 mm ano-1. Já o máximo comprimento do fruto (23cm) foi observado na lâmina de 296,9mm ano-1. A massa do fruto máxima estimado de 1.736g foi constatado na lâmina de 356,4mm ano-1. No contexto, a irrigacão contribui de forma positiva no desenvolvimento vegetativo e rendimento da fruta do abacaxizeiro. Ressalta-se remuneracão mensal líquida de R$ 1.161,17ha-1, quando se adota lâmina de irrigacão de 356,4mm ano-1.

Desenvolvimento de porta-enxertos de umbuzeiro em resposta à adubação com nitrogênio e fósforo / 'Umbuzeiro' rootstocks development as a answer for fertilization with nitrogen and phosphorous

A adubação, notadamente com nitrogênio e fósforo, é fundamental no estádio de desenvolvimento inicial de mudas de frutíferas. Porém, existem poucas informações científicas com respeito do umbuzeiro. Assim, objetivou-se avaliar o efeito de doses de nitrogênio e fósforo no desenvolvimento de porta-enxertos de umbuzeiro (Spondias tuberosa Arr. Câm.). O experimento foi conduzido sob telado, na Universidade Federal de Sergipe, em um delineamento em blocos ao acaso, em esquema fatorial 4 x 4, sendo quatro níveis de nitrogênio e quatro de fósforo (0, 50, 100 e 150kg ha-1 de N e P2O5, respectivamente na forma de uréia e superfosfato simples, em quatro repetições. O maior ganho em altura (12,52cm) foi obtido com as doses de 97,58kg ha-1 de N, enquanto o maior incremento no diâmetro do colo (2,18mm) foi obtido com as doses de 150kg ha-1 de N e 150kg ha-1 de P2O5. O maior número de folhas foi observado na presença de 126,03kg ha-1 de N e 150kg ha-1 de P2O5. A maior produção de massa seca da parte aérea total foi constatada na dose de 98,71kg ha-1 de N e 150kg ha-1 de P2O5. A área foliar cresceu linearmente para ambos fatores As adubações estudadas contribuem de forma positiva para a formação de mudas de umbuzeiro, podendo antecipar a formação de porta-enxertos para algumas fruteiras do gênero Spondias. Doses de fósforo a partir de 150kg ha-1 não são recomendadas quando se pretende produzir picles, a partir do xilopódio do umbuzeiro.