Organic and mineral matter changes due to oil generation, saturation and expulsion processes based on artificial maturation experiments

Hydrous pyrolysis experiments were conducted on immature organic-rich rock with type-I kerogen to evaluate petroleum generation, saturation and expulsion processes. The experiments were carried out under isothermal conditions at ten different temperatures (280° through 360°C) for nine different time spans between 18 and 144h. Rock samples recovered from the experiments were analyzed for total organic carbon (TOC-weight%), Rock-Eval pyrolysis, vitrinite reflectance (Ro%), spectral fluorescence and visual characterization of organic matter under the microscopy. TOC, S2 and HI tend to decrease with increasing temperature and duration of the experiments as expected. The Ro% values reach up to 1.14% in the most severe experiment (i.e. 360°C/96h). The Ro% is believed to be suppressed due to hydrogen incorporation from bitumen. The bitumen production was observed with the increase of transformation index (TI) and two types of bitumen were differentiated by fluorescence color. The bitumen with yellow fluorescence was mainly composed of saturate and aromatic hydrocarbons that were probably generated earlier than the bitumen with brown fluorescence which is rich in NSO compounds. The greatest bitumen saturation occurs at TI around of 41% to 45%, when the S1 reaches its highest values. The decrease of bitumen saturation and consequent oil expulsion is marked by a reduction in S1 values and fluorescence color. This phenomenon occurs simultaneously with the development of fractures and voids in the mineral matrix which reduces the oil retention capability and facilitates the expulsion process. These observations enhanced the understanding of oil generation and saturation processes, as well as primary migration, expulsion and type of generated bitumen

Organic and mineral matter changes due to oil generation, saturation and expulsion processes based on artificial maturation experiments

Hydrous pyrolysis experiments were conducted on immature organic-rich rock with type-I kerogen to evaluate petroleum generation, saturation and expulsion processes. The experiments were carried out under isothermal conditions at ten different temperatures (280° through 360°C) for nine different time spans between 18 and 144h. Rock samples recovered from the experiments were analyzed for total organic carbon (TOC-weight%), Rock-Eval pyrolysis, vitrinite reflectance (Ro%), spectral fluorescence and visual characterization of organic matter under the microscopy. TOC, S2 and HI tend to decrease with increasing temperature and duration of the experiments as expected. The Ro% values reach up to 1.14% in the most severe experiment (i.e. 360°C/96h). The Ro% is believed to be suppressed due to hydrogen incorporation from bitumen. The bitumen production was observed with the increase of transformation index (TI) and two types of bitumen were differentiated by fluorescence color. The bitumen with yellow fluorescence was mainly composed of saturate and aromatic hydrocarbons that were probably generated earlier than the bitumen with brown fluorescence which is rich in NSO compounds. The greatest bitumen saturation occurs at TI around of 41% to 45%, when the S1 reaches its highest values. The decrease of bitumen saturation and consequent oil expulsion is marked by a reduction in S1 values and fluorescence color. This phenomenon occurs simultaneously with the development of fractures and voids in the mineral matrix which reduces the oil retention capability and facilitates the expulsion process. These observations enhanced the understanding of oil generation and saturation processes, as well as primary migration, expulsion and type of generated bitumen

Quality control of raw hazelnuts by rapid and non-invasive fingerprinting of volatile compound release

Although hazelnuts are mostly consumed after toasting and mixed with other ingredients, for manufactures it is important to have efficient quality control tests on the raw product that they purchase from farmers and suppliers. This study explores the possibility to predict sensory quality of raw hazelnuts, classified according to industrial sensory evaluation, using volatilome analysis through Proton Transfer Reaction Mass Spectrometry (PTR-MS) rapid fingerprinting. Firstly, the link between volatile markers for different visual and sensory defects was investigated. Uncompliant hazelnuts showed higher concentrations for a larger number of volatile organic compounds (VOCs) than compliant samples, including some key hazelnuts odorants like 5-methyl-4-heptanone, 5-propyldihydro-2(3H)-furanone, octanal, 2,4-nonadienal and hexanal. Secondly, by mixing defective and good quality hazelnuts, the method sensitivity in recognizing defects percentage was determined. For about 13% of the detected mass peaks, the method was able to discriminate samples containing 20% of hazelnuts with unacceptable quality from good quality samples. Finally, unsupervised data clustering of VOCs fingerprints obtained with different precursor ions (H3O+, NO+ and O2+) provided a correct classification rate higher than 90% for all ions. The applied methodology is suitable to support sensory quality control programs of raw hazelnuts in confectionary industries.</p

Diaporthe spp. main candidate causal agent in hazelnut defects in Causasian region

Production of hazelnuts is affected by defects, the incidence of which is year-dependent but also economically damaging. The objectives of the present study were to quantify the incidence of different fungal genera in hazelnuts, and define the causal agent/agents of nut defects. A 4-year study (2013 to 2016) was carried out in the Caucasus region, in an orchard planted in 2008 with hazelnut cv. Anakliuri. Hazelnuts were sampled at early and full ripening stages, observed for defects, and then associated fungi were isolated. Nuts with necrotic spots and internal browning were commonly found, and some collected in 2016 were completely rotted, wet and almost black. Alternaria, Aspergillus, Cladosporium, Colletotrichum, Diaporthe, Fusarium, Penicillium, Pestalotiopsis and Phoma spp. were regularly isolated from diseased and symptomless nuts. Diaporthe spp. was the dominant genus, with increasing incidence from early to full ripening, and were more isolated from defected compared to healthy kernels and in the years with the greatest incidence of defects. Rainfall was associated with the incidence of nut defects. The role of Diaporthe as a key cause hazelnut defects was confirmed by pathogenicity tests. Three isolates from the Diaporthe population were identified as D. eres on the basis of EF, ACT, TUB and ITS loci. This supports the crucial role of climate during the crop-growing season for the development of defects in hazelnuts caused by Diaporthe

Cognitive impairment and dentate gyrus synaptic dysfunction in experimental parkinsonism

Parkinson's disease (PD) is characterized by the progressive degeneration of the nigrostriatal dopaminergic pathway and the emergence of rigidity, tremor, and bradykinesia. Accumulating evidence indicates that PD is also accompanied by nonmotor symptoms including cognitive deficits, often manifested as impaired visuospatial memory

DEFHAZ: A Mechanistic Weather-Driven Predictive Model for Diaporthe eres Infection and Defective Hazelnut Outbreaks

The browning of the internal tissues of hazelnut kernels, which are visible when the nuts are cut in half, as well as the discolouration and brown spots on the kernel surface, are important defects that are mainly attributed to Diaporthe eres. The knowledge regarding the Diaporthe eres infection cycle and its interaction with hazelnut crops is incomplete. Nevertheless, we developed a mechanistic model called DEFHAZ. We considered georeferenced data on the occurrence of hazelnut defects from 2013 to 2020 from orchards in the Caucasus region and Turkey, supported by meteorological data, to run and validate the model. The predictive model inputs are the hourly meteorological data (air temperature, relative humidity, and rainfall), and the model output is the cumulative index (Dh-I), which we computed daily during the growing season till ripening/harvest time. We established the probability function, with a threshold of 1% of defective hazelnuts, to define the defect occurrence risk. We compared the predictions at early and full ripening with the observed data at the corresponding crop growth stages. In addition, we compared the predictions at early ripening with the defects observed at full ripening. Overall, the correct predictions were &gt;80%, with &lt;16% false negatives, which confirmed the model accuracy in predicting hazelnut defects, even in advance of the harvest. The DEFHAZ model could become a valuable support for hazelnut stakeholders

Impact of Pre-Dialysis Care on Clinical Outcomes in Peritoneal Dialysis Patients

Background: Structured pre-dialysis care is associated with an increase in peritoneal dialysis (PD) utilization, but not with peritonitis risk, technical and patient survival. This study aimed at analyzing the impact of pre-dialysis care on these outcomes. Methods: All incident patients starting PD between 2004 and 2011 in a Brazilian prospective cohort were included in this analysis. Patients were divided into 2 groups: early pre-dialysis care (90 days of follow-up by a nephrology team); and late pre-dialysis care (absent or less than 90 days follow-up). The socio-demographic, clinical and biochemical characteristics between the 2 groups were compared. Risk factors for the time to the first peritonitis episode, technique failure and mortality based on Cox proportional hazards models. Results: Four thousand one hundred seven patients were included. Patients with early pre-dialysis care presented differences in gender (female-47.0 vs. 51.1%, p = 0.01); race (white-63.8 vs. 71.7%, p < 0.01); education (<4 years-61.9 vs. 71.0%, p < 0.01), respectively, compared to late care. Patients with early pre-dialysis care presented a higher prevalence of comorbidities, lower levels of creatinine, phosphorus, and glucose with a significantly better control of hemoglobin and potassium serum levels. There was no impact of pre-dialysis care on peritonitis rates (hazard ratio (HR) 0.88; 95% CI 0.77-1.01) and technique survival (HR 1.12; 95% CI 0.92-1.36). Patient survival (HR 1.20; 95% CI 1.03-1.41) was better in the early pre-dialysis care group. Conclusion: Earlier pre-dialysis care was associated with improved patient survival, but did not influence time to the first peritonitis nor technique survival in this national PD cohort.School of Medicine Pontifícia Universidade Católica Do Paraná (PUCPR), Rua Imaculada Conceição, 1155Pontifícia Universidade Católica Do Rio Grande Do sul (PUCRS)Universidade Estadual Paulista-UNESPUniversidade Federal de Juiz de Fora-UFJFUniversidade Estadual Paulista-UNES