Effects of wildfire and postfire floods on stonefly detritivores of the Pajarito Plateau, New Mexico

Wildfires alter the quantity and quality of allochthonous detritus in streams by burning riparian vegetation and through flushing during postfire floods. As such, fire disturbance may negatively affect detritivorous insects that consume coarse organic matter. We assessed how 2 crown fires impacted stonefly detritivores in streams of the Pajarito Plateau, New Mexico. We documented stonefly populations before and after the fires and postfire floods, and compared recovery trajectories among unburned, lightly burned, and severely burned reaches. We also conducted experiments to assess burned detritus as a food resource for Pteronarcella badia Hagen. Specifically, we characterized microbial conditioning, nutrient content, and breakdown rates of burned and unburned deciduous leaves and pine needles. We compared colonization of P. badia in field-placed leaf packs and growth of P. badia in a microcosm experiment on burned and unburned treatments. Detritivorous stoneflies in Plateau streams survived wildfire, but were extirpated from burned reaches after severe postfire floods in both Capulin and Guaje canyon. In Guaje Canyon, Amphinemura banksi Baumann and Gaufin was more resilient to flood disturbance than P. badia and recolonized soon after floods abated, whereas recolonization of A. banksi was delayed in Capulin Canyon. Experiments revealed that detritus quality did not explain slow recovery; despite reduced microbial conditioning and decomposition rates, P. badia colonized and grew well on burned detritus. Instead, postfire floods removed shredder stoneflies and their detrital resources; and traits such as body size, voltinism, and dispersal likely interacted with the postfire landscape to shape recovery trajectories in burned streams. Los incendios cambian la cantidad y calidad de la materia orgánica alóctona en los ríos mediante la quema de la vegetación ribereña; además, las inundaciones después de los incendios se llevan materia orgánica río abajo. Como tal, la perturbación por incendio puede afectar negativamente a los insectos detritívoros que consumen la materia orgánica gruesa. Evaluamos cómo 2 fuegos de copas afectaron a los plecópteros detritívoros en arroyos del Altiplano Pajarito, NM. Documentamos las poblaciones de plecópteros antes y después de los incendios e inundaciones y comparamos las trayectorias de recuperación entre áreas no quemadas, levemente quemadas y gravemente quemadas. También llevamos a cabo experimentos para evaluar los detritos quemado como fuente alimenticia para Pteronarcella badia Hagen. Específicamente, caracterizamos el acondicionamiento microbiano, el contenido de nutrientes y las tasas de descomposición de hojas caducifolias y hojas de pino quemadas y no quemadas. Comparamos la colonización de P. badia en paquetes de hojas colocadas en el campo, y su crecimiento en un experimento de microcosmos, en detrito quemado y no quemado. Los plecópteros detritívoros en los arroyos del Altiplano sobrevivieron a los incendios pero fueron extirpados de las áreas quemadas después de inundaciones severas que siguieron a incendios en los cañones Capulin y Guaje. En Guaje, Amphinemura banksi Baumann y Gaufin fue más resistente a la perturbación por inundación que P. badia y recolonizó poco después de que la inundación cedió, mientras que la recolonización de A. banksi tardó más en Capulin. Los experimentos revelaron que la calidad de los detritos no explican esta lenta recuperación; a pesar del menor acondicionamiento microbiano y las tasas de descomposición más bajas, P. badia colonizó y creció bien en detritos quemados. Es probable que las inundaciones después de los incendios se hayan llevado a los plecópteros y a los detritos que consumen, y que los rasgos tales como el tamaño del cuerpo, el voltinismo, y la dispersión hayan interactuado con el paisaje después del incendio para determinar las trayectorias de recuperación en arroyos quemados.     

Recuperation of nitrogen cycling in Amazonian forests following agricultural abandonment

Phosphorus (P) is generally considered the most common limiting nutrient for productivity of mature tropical lowland forests growing on highly weathered soils. It is often assumed that P limitation also applies to young tropical forests, but nitrogen (N) losses during land-use change may alter the stoichiometric balance of nutrient cycling processes. In the Amazon basin, about 16% of the original forest area has been cleared, and about 30-50% of cleared land is estimated now to be in some stage of secondary forest succession following agricultural abandonment. Here we use forest age chronosequences to demonstrate that young successional forests growing after agricultural abandonment on highly weathered lowland tropical soils exhibit conservative N-cycling properties much like those of N-limited forests on younger soils in temperate latitudes. As secondary succession progresses, N-cycling properties recover and the dominance of a conservative P cycle typical of mature lowland tropical forests re-emerges. These successional shifts in N:P cycling ratios with forest age provide a mechanistic explanation for initially lower and then gradually increasing soil emissions of the greenhouse gas nitrous oxide (N(2)O). The patterns of N and P cycling during secondary forest succession, demonstrated here over decadal timescales, are similar to N- and P-cycling patterns during primary succession as soils age over thousands and millions of years, thus revealing that N availability in terrestrial ecosystems is ephemeral and can be disrupted by either natural or anthropogenic disturbances at several timescales.     

Forecasting models in the manufacturing processes and operations management: Systematic literature review

The purpose of this paper is to present the result of a systematic literature review regarding the application and development of forecasting models in the industrial context, especially the context of manufacturing processes and operations management. The study was conducted considering the preparation of an established research protocol to know, discuss, and analyze the main approaches adopted by researchers in the field. To achieve this objective, we analyzed 354 recent papers published in periodicals between 2008 and 2018. This paper makes three main contributions to the field: (i) it presents an updated portfolio of prediction models in the industrial context, providing a reference point for researchers and industrial managers; (ii) it presents a characterization of the field of study through the identification of publication vehicles, frequency, and the principal authors and countries related to the development of research on the theme; (iii) it proposes a unified framework, listing the characteristics of the prediction models with their respective application contexts, identifying the current research directions to provide theoretical aids for the development of new approaches to forecasting in industry. The results of this study provide an empirical base for further discussions on studies that focus on forecasting in the industrial context.     

Melt Infiltration Ability and Microstructural Evolution of Fe40Al/ TiC Composites System

Pressureless melt infiltration is an economic route f or preparation of high-density ceramic/melt composites. In this study, the Fe40 Al iron aluminide intermetallic, a low cost material of excellent oxidation and corrosion resistance, was used as binder for fabricating Fe40Al/TiC composites b y pressureless melt infiltration. The wetting ability of liquid Fe40Al in porous TiC pre-form was studied by in-situ monitoring the melting and infiltration p rocess. The infiltration ability was investigated by ob...     

Deficiency of UBR1, a ubiquitin ligase of the N-end rule pathway, causes pancreatic dysfunction, malformations and mental retardation (Johanson-Blizzard syndrome)

Johanson-Blizzard syndrome (OMIM 243800) is an autosomal recessive disorder that includes congenital exocrine pancreatic insufficiency, multiple malformations such as nasal wing aplasia, and frequent mental retardation. We mapped the disease-associated locus to chromosome 15q14-21.1 and identified mutations, mostly truncating ones, in the gene UBR1 in 12 unrelated families with Johanson-Blizzard syndrome. UBR1 encodes one of at least four functionally overlapping E3 ubiquitin ligases of the N-end rule pathway, a conserved proteolytic system whose substrates include proteins with destabilizing N-terminal residues. Pancreas of individuals with Johanson-Blizzard syndrome did not express UBR1 and had intrauterine-onset destructive pancreatitis. In addition, we found that Ubr1(-/-) mice, whose previously reported phenotypes include reduced weight and behavioral abnormalities, had an exocrine pancreatic insufficiency, with impaired stimulus-secretion coupling and increased susceptibility to pancreatic injury. Our findings indicate that deficiency of UBR1 perturbs the pancreas' acinar cells and other organs, presumably owing to metabolic stabilization of specific substrates of the N-end rule pathway.     

Revisiting the metabolic syndrome: the emerging role of aquaglyceroporins

The metabolic syndrome (MetS) includes a group of medical conditions such as insulin resistance (IR), dyslipidemia and hypertension, all associated with an increased risk for cardiovascular disease. Increased visceral and ectopic fat deposition are also key features in the development of IR and MetS, with pathophysiological sequels on adipose tissue, liver and muscle. The recent recognition of aquaporins (AQPs) involvement in adipose tissue homeostasis has opened new perspectives for research in this field. The members of the aquaglyceroporin subfamily are specific glycerol channels implicated in energy metabolism by facilitating glycerol outflow from adipose tissue and its systemic distribution and uptake by liver and muscle, unveiling these membrane channels as key players in lipid balance and energy homeostasis. Being involved in a variety of pathophysiological mechanisms including IR and obesity, AQPs are considered promising drug targets that may prompt novel therapeutic approaches for metabolic disorders such as MetS. This review addresses the interplay between adipose tissue, liver and muscle, which is the basis of the metabolic syndrome, and highlights the involvement of aquaglyceroporins in obesity and related pathologies and how their regulation in different organs contributes to the features of the metabolic syndrome.