Biomass with a large amount of moisture is well-suited to be processed by supercritical water gasification, SCWG. The precipitation of inorganics, together with char formation and re-polymerization, ...can cause reactor plugging and stop the process operations. When plugging occurs, sudden injections of relatively large mass quantities take place, influencing the mass flow dynamics significantly in the process. Reactor plugging is a phenomenon very well observed during SCWG of industrial feedstock, which hinders scale-up initiatives, and it is seldom studied with precision in the literature. The present study provides an accurate evaluation of continuous tubular reactor dynamics in the event of sudden injections of water. An interpretation of the results regarding water properties at supercritical conditions contributes to comprehending mass and heat transfer when plugging occurs. Experiments are then compared to SCWG of a biomass sample aiming to give key insights into heat transfer and fluid dynamics mechanisms that could help develop operational and control strategies to increase the reliability of SCWG. In addition, a simplified model is presented to assess the effect of material integrity on burst-event likelihood, which states that SCWG is safe to operate, at 250 bar and 610 °C, in tubular reactors made of 0.22 wall thickness-to-diameter ratio Inconel-625 with superficial microfractures smaller than 30 µm. We also suggest improvement opportunities for the safety of SCWG in continuous operation mode.
The Relationship Between Blood Pressure and Pain Saccò, Marcella; Meschi, Michele; Regolisti, Giuseppe ...
The journal of clinical hypertension (Greenwich, Conn.),
August 2013, Letnik:
15, Številka:
8
Journal Article
Recenzirano
Odprti dostop
The relationship between pain and hypertension is potentially of great pathophysiological and clinical interest, but is poorly understood. The perception of acute pain initially plays an adaptive ...role, which results in the prevention of tissue damage. The consequence of ascending nociception is the recruitment of segmental spinal reflexes through the physiological neuronal connections. In proportion to the magnitude and duration of the stimulus, these spinal reflexes cause the activation of the sympathetic nervous system, which increases peripheral resistances, heart rate, and stroke volume. The response also involves the neuroendocrine system, and, in particular, the hypothalamic‐pituitary‐adrenal axis, in addition to further activation of the sympathetic system by adrenal glands. However, in proportion to an elevation in resting blood pressure, there is a contemporary and progressive reduction in sensitivity to acute pain, which could result in a tendency to restore arousal levels in the presence of painful stimuli. The pathophysiological pattern is significantly different in the setting of chronic pain, in which the adaptive relationship between blood pressure and pain sensitivity is substantially reversed. The connection between acute or chronic pain and cardiovascular changes is supported observationally, but some of this indirect evidence is confirmed by experimental models and human studies. The pain regulatory process and functional interaction between cardiovascular and pain regulatory systems are briefly reviewed. Various data obtained are described, together with their potential clinical implications.
Questions
Responses of wetland systems to grazing can be highly variable with both positive or negative responses. However, the sustainable use of wetlands for grazing will depend on the management ...implemented and the resilience of each type of them. In this context, we addressed the question: will the vegetation in the studied wetland be able to recover its structural and functional parameters in the short term after livestock exclusion?
Location
Temperate fluvial wetlands in the middle Delta of the Paraná River, Argentina, South America.
Methods
We evaluated the effect of cattle ranching on vegetation composition and diversity by determining changes in species richness and evenness, biomass (green and dry vegetative, and reproductive biomass), and litter content. We also analyzed the changes in biomass of weeds and of species according to their forage quality, toxicity, and growth form. We applied a randomized block design (by topographic position) with repeated measures over time, using livestock exclusion as treatment.
Results
After 16 months, livestock exclusion affected vegetation species richness, but did not have a significant effect on diversity due to a slightly compensatory effect of evenness. Species composition differed markedly among treatments over time. There was an increase in dry and green vegetative biomass and litter content after eight months of exclusion, while changes in reproductive biomass occurred later. The increase in these variables was closely related to changes in biomass of species with erect habit and good forage quality.
Conclusions
Livestock exclusion increased the forage value for the studied wetland by the development of natural palatable species typical of these environments. This shift in species composition promoted a higher production in biomass in the ungrazed areas. This suggests a remarkable recovery of the structural and functional parameters of the vegetation communities in the short term (two years).
In a wetland of the Paraná River Delta (Argentina) we found that livestock exclusion for two years reduced species richness, had no effect on diversity because of evenness, increased biomass and litter content, and favored the development of species with erect habit and good forage quality. Despite the short timespan, this wetland showed a remarkable recovery of the structural and functional parameters.
The discovery of different podocyte autoantibodies in membranous nephropathy (MN) raises questions about their pathogenetic and clinical meaning. This study sought to define antibody isotypes and ...correlations; to compare levels in MN, other glomerulonephritides, and controls; and to determine their association with clinical outcomes.
Serum IgG(1), IgG(3), and IgG(4) against aldose reductase (AR), SOD2, and α-enolase (αENO) were measured at diagnosis in 186 consecutive MN patients, in 96 proteinuric controls (36 with FSGS, and 60 with IgA nephropathy), and in 92 healthy people recruited in four Italian nephrology units. Anti-phospholipase A2 receptor (PLA2r) and anti-neutral endopeptidase (NEP) IgG(4) were titrated in the same specimens. Association with 1-year follow-up clinical parameters was studied in 120 patients.
IgG(4) was the most common isotype for all antibodies; IgG(1) and IgG(3) were nearly negligible. IgG(4) levels were positive in a significant proportion of MN patients (AR, 34%; SOD2, 28%; αENO, 43%). Antibody titers were higher in MN than in healthy and pathologic controls (P<0.005). Anti-NEP IgG(4) did not differ from normal controls (P=0.12). Anti-PLA2r IgG(4) was detected in 60% of patients and correlated with anti-AR, anti-SOD2, and anti-αENO IgG(4) (P<0.001). In MN patients negative for the whole antibody panel (20%), 1-year proteinuria was lower compared with patients with at least one antibody positivity (P<0.05).
Our data suggest that IgG(4) is the prevalent isotype for antibodies against cytoplasmic antigens of podocytes (AR, SOD2, αENO). Their levels were higher than in other proteinuric glomerulonephritides and in normal controls and were correlated with anti-PLA2r. Only baseline negativity for all known antibodies predicted lower 1-year proteinuria.
Rural abandonment is a global phenomenon promoted by biophysical, socio-economic, and socio-productive causes, leading to the disappearance of traditional agricultural practices and serious impacts ...on food security and local livelihoods. This phenomenon is more complex in drylands since the lost of productive land is unlikely to be recovered due to the limited availability of water resources. This study aimed to identify abandoned agricultural lands in a sector located east of the northern oasis of Mendoza (Argentina) and determine the main driving forces leading this process. The interdisciplinary perspective employed included the Normalized Difference Vegetation Index (NDVI) difference technique implemented on Landsat images, the boosted regression trees analysis of spatially explicit drivers, and a digital survey providing perception assessments from local producers and their technical advisors. Abandoned agricultural land has increased by 92% between 2002 and 2020, being accessibility, crop type, vulnerable living conditions of the local population, availability of irrigation water and labor, and the lack of profitability, the main drivers identified by both sources of information (spatial model and social perception). The proposed approach contributes to monitore productive resources and land-use planning with a holistic and long-term vision. Highlights: Rural abandonment was addressed as an environmental problem from an interdisciplinary perspective. Abandoned land was detected using the Normalized Difference Vegetation Index (NDVI) difference technique. The spatial analysis and the perception study indicated mostly the same land-use change drivers. Abandoned agricultural land increased by 92% between 2002 and 2020 in San Martín (Mendoza). The main drivers of abandonment were accessibility, crop type, vulnerable living conditions of the local population, availability of irrigation water and labor, and the lack of profitability.
Nephrosis and a rapid decline in kidney function characterize HIV-associated nephropathy (HIVAN). Histologically, HIVAN is a collapsing focal segmental glomerulosclerosis with prominent tubular ...damage. We explored the expression of neutrophil gelatinase-associated lipocalin (NGAL), a marker of tubular injury, to determine whether this protein has the potential to aid in the noninvasive diagnosis of HIVAN. We found that expression of urinary NGAL was much higher in patients with biopsy-proven HIVAN than in HIV-positive and HIV-negative patients with other forms of chronic kidney disease. In the HIV-transgenic mouse model of HIVAN, NGAL mRNA was abundant in dilated, microcystic segments of the nephron. In contrast, urinary NGAL did not correlate with proteinuria in human or in mouse models. These data show that marked upregulation of NGAL accompanies HIVAN and support further study of uNGAL levels in large cohorts to aid in the noninvasive diagnosis of HIVAN and screen for HIVAN-related tubular damage.
We performed a genome-wide association study (GWAS) of IgA nephropathy (IgAN), the most common form of glomerulonephritis, with discovery and follow-up in 20,612 individuals of European and East ...Asian ancestry. We identified six new genome-wide significant associations, four in ITGAM-ITGAX, VAV3 and CARD9 and two new independent signals at HLA-DQB1 and DEFA. We replicated the nine previously reported signals, including known SNPs in the HLA-DQB1 and DEFA loci. The cumulative burden of risk alleles is strongly associated with age at disease onset. Most loci are either directly associated with risk of inflammatory bowel disease (IBD) or maintenance of the intestinal epithelial barrier and response to mucosal pathogens. The geospatial distribution of risk alleles is highly suggestive of multi-locus adaptation, and genetic risk correlates strongly with variation in local pathogens, particularly helminth diversity, suggesting a possible role for host-intestinal pathogen interactions in shaping the genetic landscape of IgAN.
Se presenta una lista con las 32 especies de Heteroptera colectadas con trampas de caída en el INTA (Instituto Nacional de Tecnología Agropecuaria) Delta del Paraná (Partido de Campana, Buenos ...Aires). Se mencionan como primer registro para la provincia a 2 especies: Fulvius bisbistillatus (Stål) (Miridae) y Pselliopus ornaticeps (Stål) (Reduviidae). Se realizó un análisis de correlación de rangos de Spearman (r) y un análisis de correspondencia, con el fin de evaluar la variación espacial y temporal de las comunidades de heterópteros de los distintos usos de la tierra seleccionados.
•Increasing land-use intensity erodes woody taxonomic and functional diversities and, ultimately, carbon storage.•Disturbance by logging and/or livestock grazing reduced carbon stored in shrubs, ...trees, roots, litter, and dead plants.•Woody species richness and trait diversity seem more important than trait dominance in determining carbon stocks.
Forest ecosystems play a key role in providing multiple ecosystem services, such as carbon fixation and storage, but face pressures from human development that jeopardize their integrity and functioning. Accurately understanding the relationships between land use-intensity, biodiversity, and carbon storage is important for developing viable strategies to promote carbon sequestration. Here, we analyzed the effect of land-use intensity on the relationship between woody plant functional diversity and carbon storage in Prosopis woodlands of the central Monte desert of Argentina. We worked in sixteen 900 m2 square plots along disturbance gradients, eight located in highly disturbed woodlands close to livestock settlements and eight in slightly disturbed woodlands ca. 2 km away from settlements. We measured woody plant taxonomic and functional diversity and dominance metrics, and estimated carbon stocks in biomass, necromass and soil organic compartments. Our study shows that increasing land-use intensity erodes taxonomic and functional diversities and, ultimately, carbon storage. We found that lower carbon stocks around livestock settlements were driven by shrubs, trees, roots, litter, and dead plants, but were unaffected by the herb, woody debris, and soil compartments. Furthermore, positive relationships among woody species richness and functional trait diversity seem more important than the existence of few highly dominant species in determining carbon storage, providing stronger evidence for niche complementary than for mass ratio effects. We hope our study contributes to the understanding how livestock management practices influence carbon storage in Prosopis woodlands.
The type and the extent of tissue damage inform the prognosis of chronic kidney disease (CKD), but kidney biopsy is not a routine test. Urinary tests that correlate with specific histological ...findings might serve as surrogates for the kidney biopsy. We used immunoblots and ARCHITECT-NGAL assays to define the immunoreactivity of urinary neutrophil gelatinase–associated lipocalin (NGAL) in CKD, and we used mass spectroscopy to identify associated proteins. We analyzed kidney biopsies to determine whether specific pathological characteristics associated with the monomeric NGAL species. Advanced CKD urine contained the NGAL monomer as well as novel complexes of NGAL. When these species were separated, we found a significant correlation between the NGAL monomer and glomerular filtration rate (r=-0.53, P<0.001), interstitial fibrosis (mild vs. severe disease; mean 54 vs. 167μg uNGAL/g Cr, P<0.01), and tubular atrophy (mild vs. severe disease; mean 54 vs. 164μg uNGAL/g Cr, P<0.01). Monospecific assays of the NGAL monomer demonstrated a correlation with histology that typifies progressive, severe CKD.
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