Aerosols in the Pre-industrial Atmosphere

Purpose of Review: We assess the current understanding of the state and behaviour of aerosols under pre-industrial conditions and the importance for climate. Recent Findings: Studies show that the magnitude of anthropogenic aerosol radiative forcing over the industrial period calculated by climate models is strongly affected by the abundance and properties of aerosols in the pre-industrial atmosphere. The low concentration of aerosol particles under relatively pristine conditions means that global mean cloud albedo may have been twice as sensitive to changes in natural aerosol emissions under pre-industrial conditions compared to present-day conditions. Consequently, the discovery of new aerosol formation processes and revisions to aerosol emissions have large effects on simulated historical aerosol radiative forcing. Summary: We review what is known about the microphysical, chemical, and radiative properties of aerosols in the pre-industrial atmosphere and the processes that control them. Aerosol properties were controlled by a combination of natural emissions, modification of the natural emissions by human activities such as land-use change, and anthropogenic emissions from biofuel combustion and early industrial processes. Although aerosol concentrations were lower in the pre-industrial atmosphere than today, model simulations show that relatively high aerosol concentrations could have been maintained over continental regions due to biogenically controlled new particle formation and wildfires. Despite the importance of pre-industrial aerosols for historical climate change, the relevant processes and emissions are given relatively little consideration in climate models, and there have been very few attempts to evaluate them. Consequently, we have very low confidence in the ability of models to simulate the aerosol conditions that form the baseline for historical climate simulations. Nevertheless, it is clear that the 1850s should be regarded as an early industrial reference period, and the aerosol forcing calculated from this period is smaller than the forcing since 1750. Improvements in historical reconstructions of natural and early anthropogenic emissions, exploitation of new Earth system models, and a deeper understanding and evaluation of the controlling processes are key aspects to reducing uncertainties in future

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Effect of Venting Holes to Relieve Wave Impact Pressures on Flood Gates with Overhangs

Flood gates in storm surge barriers or outlet sluices can be prone to violent wave impacts. When an obstruction is present at the sea side above the gate, confinement of the incoming waves can lead to impulsive wave loads, even when the waves are non-breaking. The large loads can increase the stresses in the gate and structure considerably. One of the measures that is often discussed to relieve the pressures of these impacts is to apply small openings in the gates. In this paper the potential effect of these venting holes on the wave impact loads is determined. The decrease in impact pressure impulse is determined for a range of venting hole geometries is determined by numerical 2D and 3D solutions of a schematized wave impact. In this model the pressure impulse P (integral of the local pressure over the small impact duration) is determined directly by the so-called pressure impulse theory. The potential decrease in pressure impulse due to wave impacts is presented. Moreover, some initial CFD modelling is applied, and the applicability of the pressure impulse theory is discussed.Hydraulic Structures and Flood Ris

Characterization of Bio-oils from Different Pyrolysis Process Steps and Biomass Using High-Resolution Mass Spectrometry

Next-generation biofuels have been widely investigated because they have particular advantages compared to first-generation biofuels. Pyrolysis is an example of a thermochemical route extensively used in oil and coal industries worldwide to produce these biofuels. Strategies for low-cost upgrading are among the biggest challenges facing the adoption of bio-oils in the development of commercial biofuels. Specific biomass sources could be the best option for generating bio-oil with the required properties. For this, it is necessary to understand the composition of these biomasses and their bio-oils. Here, we analyzed bio-oil samples from the fast pyrolysis of different biomasses collected during two different steps of the process by direct-infusion high-resolution mass spectrometry. First, a comparative study of two common high-resolution mass spectrometers, quadrupole time-of-flight mass spectrometry (Q-TOF MS) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), was performed to validate the methodology and to investigate the differences in mass discrimination and resolution. FT-ICR MS showed the best performance because of its unsurpassed resolution and accuracy. We apply the common petroleomics tools to interpret the mass spectra obtained. The FT-ICR MS analysis reveals that bio-oils are dominated by O_<i>x</i> species. The class profile of bio-oils was strongly affected by the biomass and steps of the pyrolysis process

Gasoline from biomass through refinery-friendly carbohydrate-based bio-oil produced by ketalization

The introduction of biomass-derived compounds as an alternative feed into the refinery structure that already exists can potentially converge energy uses with ecological sustainability. Herein, we present an approach to produce a bio-oil based on carbohydrate-derived isopropylidene ketals obtained by reaction with acetone under acidic conditions directly from second-generation biomass. The obtained bio-oil showed a greater chemical inertness and miscibility with gasoil than typical bio-oil from fast pyrolysis. Catalytic upgrading of the bio-oil over zeolites (USY and Beta) yielded gasoline with a high octane number. Moreover, the co-processing of gasoil and bio-oil improved the gasoline yield and quality compared to pure gasoil and also reduced the amount of oxygenated compounds and coke compared with pure bio-oil, which demonstrates a synergistic effect. Refinery refinement: The conversion of biomass into fuel by using a regular refinery installation can largely mitigate CO emissions. This goal is achieved by a two-step process: biomass is transformed into a carbohydrate-based bio-oil produced by hydrolysis-ketalization reactions, then a gasoline with a high octane number is produced by catalytic upgrading

Tamanho da semente e substratos na germinação e crescimento inicial de mudas de cagaiteira Seeds sizes and substrates on germination of seed and initial grownth of cagaiteira

A cultura da cagaiteira apresenta perspectivas de expansão no cerrado e no Nordeste brasileiro. Com o presente trabalho teve-se como objetivo avaliar as características de germinação de sementes de cagaiteira de diferentes tamanhos em três tipos de substratos. O delineamento experimental utilizado foi de blocos inteiramente casualizados em um esquema de parcela subdividida, com fatorial (2 x3), consistindo de dois tamanhos de sementes, grandes (13,5 mm de largura, 15,91 mm de comprimento e 1,41 g de massa) e pequenas (9,94 mm de largura, 12,19 mm de comprimento e 0,68 g de massa) em três tipos de substratos (plugmix; areia, argila e esterco de curral, na proporção v/v 1:1:1; e areia e argila na proporção v/v 1:1). Pelos resultados, observou-se que, independentemente do tamanho da semente e do tipo de substrato, não houve diferenças significativas quanto à porcentagem de emergência, que foi superior a 90%. Nas características de índice de velocidade de emergência, altura e número de folhas, observou-se superioridade para as plantas provenientes de sementes grandes. Em relação aos diferentes tipos de substratos, houve diferenças significativas para as características de altura e número de folhas, indicando a superioridade dos substratos à base de areia e argila.<br>The culture of cagaita presents perspectives of expansion in the open pasture and Brazilian northeast, this culture is usually spread by seeds. This work aimed at evaluating the characteristics of germination of different sizes of seeds on three types of substrates. The experimental was designed in blocks at random outlined in subparcels with four replications, in a factorial system of two seed sizes, big and small, on three types of substrates (plugmix, sand; clay and manure; sand and clay). The results showed that regardless of the seed size there were not significant differences for germination percentage. When analyzed characteristic of germination speed index, height and leaf number, significant superiority was observed for the plants from big seeds. Significant differences for characteristics of height and leaf number were also observed indicating superiority of sand and clay substratum. We can conclude that independently of the substratum type, percentages of cagaita seed germination are over 90%, but plantlets initial growth may be damaged if the nurseryman does not use a balanced and appropriate substratum to the specie

Efferocytosis of SARS-CoV-2-infected dying cells impairs macrophage anti-inflammatory functions and clearance of apoptotic cells

COVID-19 is a disease of dysfunctional immune responses, but the mechanisms triggering immunopathogenesis are not established. The functional plasticity of macrophages allows this cell type to promote pathogen elimination and inflammation or suppress inflammation and promote tissue remodeling and injury repair. During an infection, the clearance of dead and dying cells, a process named efferocytosis, can modulate the interplay between these contrasting functions. Here, we show that engulfment of SARS-CoV-2-infected apoptotic cells exacerbates inflammatory cytokine production, inhibits the expression of efferocytic receptors, and impairs continual efferocytosis by macrophages. We also provide evidence supporting that lung monocytes and macrophages from severe COVID-19 patients have compromised efferocytic capacity. Our findings reveal that dysfunctional efferocytosis of SARS-CoV-2-infected cell corpses suppresses macrophage anti-inflammation and efficient tissue repair programs and provides mechanistic insights for the excessive production of pro-inflammatory cytokines and accumulation of tissue damage associated with COVID-19 immunopathogenesis

Utility of the Neuropathic Pain Symptom Inventory in people with spinal cord injury

Cohort/psychometric study OBJECTIVES: The primary objective was to determine the psychometric properties and the utility of the Neuropathic Pain Symptom Inventory (NPSI) in subgrouping people with moderate to severe neuropathic pain after spinal cord injury (SCI). University-based laboratory in Miami, FL USA. Seventy-two people with chronic SCI and neuropathic pain were included in this study. The NPSI, Numeric Rating Scale (NRS), Multidimensional Pain Inventory pain severity and perceived support subscales (MPI-PS and MPI-S, respectively), and the Coping Strategies Questionnaire were administered. The NPSI was administered twice, with a 2-4-week period between measurement sessions. The NPSI total score demonstrated good internal consistency with a Cronbach's alpha of 0.70. The test-retest reliability (intraclass correlations) ranged from 0.65 to 0.73 for the NPSI subscores and 0.79 for the total NPSI score. Further, construct validity was supported by moderate and significant positive correlations with the pain intensity NRS and pain severity subscale of the MPI (MPI-PS) (r > 0.40). Cluster analysis of factor scores derived from NPSI subscales, NRS, and MPI-PS scores revealed three distinct subgroups: (1) low-moderate, (2) moderate, and (3) high pain symptom severity with mean NPSI sum scores of 7.1, 17.5, and 33.8, respectively. The NPSI demonstrated good psychometric properties in people with neuropathic pain after SCI. Moreover, it has utility for establishing pain symptom phenotypes