Dry Environmental Conditions Research Articles

Simple and effective method to lower body core temperatures of hyperthermic patients

Hyperthermia is a potentially life threatening scenario that may occur in patients due to accompanying morbidities, exertion, or exposure to dry and arid environmental conditions. In particular, heat stroke may result from environmental exposure combined with a lack of thermoregulation. Key clinical findings in the diagnosis of heatstroke are (1) a history of heat stress or exposure, (2) a rectal temperature greater than 40 °C, and (3) central nervous system dysfunction (altered mental state, disorientation, stupor, seizures, or coma) (Prendergast and Erickson, 2014 [1]). In these patients, it is important to bring the body's core temperature down to acceptable levels in a short period of time to avoid tissue/organ injury or death (Yoder, 2001; Casa et al., 2007 [2,3]). A number of potential approaches, both non-invasive and invasive, may be used to lower the temperature of these individuals. Non-invasive techniques generally include: evaporative cooling, ice water immersion, whole-body ice packing, strategic ice packing, and convective cooling. Invasive approaches may include gastric lavage or peritoneal lavage (Schraga and Kates [4]). The efficacy of these methods vary and select treatment approaches may be unsuitable for specific individuals (Schraga and Kates [4]). In this work, the effectiveness of radiation cooling of individuals as a stand-alone treatment and comparisons with existing noninvasive techniques are presented.

Optimisation of cutting parameters in CNC turning of EN-19 using tungsten carbide

Efficient turning of high performance EN series material can be achieved through proper selection of turning process parameters to minimise surface roughness and maximise the material removal rate. This present paper outlines an experimental study to optimise and study the effects of process parameters in CNC turning on surface roughness of EN19/AISI4140 (medium carbon steel) work material in dry environment conditions. The orthogonal array, signal to noise ratio and regression technique were employed to study the performance characteristics in CNC turning operation. Four machining parameters were chosen as process parameters. They are cutting speed, feed rate, tool nose radius and depth of cut. The experimentation plan was designed using Taguchi's L9 orthogonal array (OA) and Minitab-16 statistical software. Optimal values of process parameters for desired performance characteristics were obtained by Taguchi design of experiment. Moreover prediction models had been developed with the help of regression analysis to find the effect of cutting parameters.

A high-resolution temporal record of environmental changes in the Eastern Caribbean (Guadeloupe) from 40 to 10 ka BP

Abstract In neotropical regions, fossil bat guano accumulated over time as laminated layers in caves, hence providing a high-resolution temporal record of terrestrial environmental changes. Additionally, cave settings have the property to preserve such organic sediments from processes triggered by winds (deflation, abrasion and sandblasting) and intense rainfall (leaching away). This study reports both stable carbon and nitrogen isotope compositions of frugivorous bat guano deposited in a well-preserved stratigraphic succession of Blanchard Cave on Marie-Galante, Guadeloupe. These isotopic data are discussed with regard to climate changes and its specific impact on Eastern Caribbean vegetation during the Late Pleistocene from 40 to 10 ka cal. BP. Guano δ 13 C values are higher than modern ones, suggesting noticeable vegetation changes. This provides also evidence for overall drier environmental conditions during the Pleistocene compared to today. Meanwhile, within this generally drier climate, shifts between wetter and drier conditions can be observed. Large temporal amplitudes in both δ 13 C and δ 15 N variations reaching up to 5.9‰ and 16.8‰, respectively, also indicate these oceanic tropical environments have been highly sensitive to regional or global climatic forcing. Stable isotope compositions of bat guano deposited from 40 to 35 ka BP, the Last Glacial Maximum and the Younger-Dryas reveal relatively wet environmental conditions whereas, at least from the end of the Heinrich event 1 and the Bolling period the region experienced drier environmental conditions. Nevertheless, when considering uncertainties in the model age, the isotopic record of Blanchard Cave show relatively similar variations with known proxy records from the northern South America and Central America, suggesting thus that the Blanchard Cave record is a robust proxy of past ITCZ migration. Teleconnections through global atmospheric pattern suggest that islands of the eastern Caribbean Basin could be also under the influence of a bipolar temperature gradients that impact the mean location of the ITCZ, with a Southern Hemisphere imprint during the glacial period and a more significant role of Northern Hemisphere during the last deglaciation.

Modeling and Simulation of Gate Engineered Gate All-Around MOSFET for Bio-Molecule Detection

Objectives: In this paper, modeling and simulation of a triple material gate stack gate all around MOSFET biosensor for the detection of biomolecules under dry environment conditions has been carried out. Method: A nanocavity is formed in the proposed device and its surface potential values are estimated by solving 2D Poisson and Schrodinger equations using Leibmann’s iteration method. The surface potential values are obtained for both the presence and absence of biomolecules. To the best of our knowledge, the effect of engineering on the gate stack gate all around MOSFET biosensor characteristics has been studied for the first time and its characteristics such as sensitivity and drain current are obtained. Findings: It is found that the implementation of gate engineering in the gate stack gate all around MOSFET improves the characteristics of the device. Improvements: The proposed device may be improved by implementing the device as an optical biosensor for detection of biomolecules.

Sciuridae (Rodentia, Mammalia) from the Late Miocene of Venta del Moro (Cabriel Basin, Spain): biostratigraphical, phylogenetic and palaeoecological inferences

Fossil squirrels are relatively abundant in Aragonian and Ramblian assemblages, but very scarce in the Late Turolian and Ruscinian of the Iberian Peninsula. Until now, the locality of Venta del Moro has yielded over 4500 micromammal dental remains, but just nine of them are sciurids. In this assemblage, we have identified the taxa Pliopetaurista pliocaenica, Heteroxerus cf. mariatheresae and Atlantoxerus cf. margaritae. This is the first co-occurrence of the genera Pliopetaurista, Heteroxerus and Atlantoxerus in the same locality, being also one of the oldest records of P. pliocaenica, the oldest record of a form that could be related to A. margaritae, and the youngest record of the genus Heteroxerus. In addition, we hypothesize about the phylogeny of Pliopetaurista in the light of recent discoveries. Finally, the presence of the genera Heteroxerus and Atlantoxerus suggests an open environment and relatively dry environmental conditions, while Pliopetaurista is purportedly a flying squirrel, dweller of forested habitats and wet climates. Based on this, we infer an open environment of grassland type, bordered by forested habitats, agreeing with the conditions supposed for Venta del Moro according to its macromammal and floral assemblages.

Cyanobacteria and testate amoeba as potential proxies for Holocene hydrological changes and climate variability: Evidence from tropical coastal lowlands of SW India

Cyanobacteria and thecamoebians are the two major constituents of Non Pollen Palynomorphs (NPP) found in the palynological preparations. The former is well represented in the sediment archives while the latter has restricted occurrence in the Holocene sequence apart from the conventional organic matter of pollen and spores. Well preserved morphotypes of Gleotrichia and Rivularia are the best forms of cyanobacteria found in almost all the studied profiles and their abundance towards Early to Middle Holocene coincides with the heavy rainfall and wet climate conditions during the Holocene climate optimum (HCO). Contrary to cyanobacterial diversity, thecamoebians are restricted to Late Holocene in most of the studied profiles and their occurrence is correlated with the prevailing dry and stressful environmental conditions. The major elements of thecamoebians identified belong to Arcellaceans, Centropyxids and Cucurbitella types. Abundance of Centropyxids and Arcellaceans in Varapuzha, West Kadungallur, Koonamavu, Pachcha and Ernakulam indicates low humidity and low precipitation. However, the relative abundance of Centropyxids in Mid Holocene at Ernakulam and Koonamavu reflects the early colonization of this type competing with the cyanobacteria, whereas, Arcellaceans are essentially confined to Late Holocene. Dominance of cyanobacteria and its proliferation is directly related to freshwater influx of the rainfall as well as the local hydrological regimes associated with the active aquifers controlled by the geomorphological features of the region in which the wetland system sustained. Considering the signatures of cyanobacteria and thecamoebians observed in the sediment archives their occurrence in the wetlands during the Holocene corresponds to the hydrodynamic regimes brought in by the freshwater influx as a result of monsoon variability. The well preserved cyanobacterial signatures in sediment archives of Kerala coast and their scarcity or even absence elsewhere along the west coast of India indicates that they are exclusively adapted to the wetland habitats where the hydrodynamic regimes are regularly controlled by fresh water influx in the form of extended rainy days of the monsoon system.

Mountain Nardus stricta grasslands as a relic of past farming – the effects of grazing abandonment in relation to elevation and spatial scale

The decline of grazing management in mountains has resulted in a dramatic decrease of areas occupied by semi-natural grasslands with Nardus stricta. In order to effectively protect existing fragments, it is important to understand the mechanisms governing the organization of communities with Nardus. The aim of this study was to quantify the relative impact of the time span of abandonment and also of topographic and spatial factors on the species composition of montane and subalpine grasslands. Old and recent phytosociological data from three distinct regions in the northern part of the Carpathians were compared by indirect and direct ordination methods. The majority of the explained variation at the supraregional scale was associated with the joint effect of spatial trends and elevation above sea level. At the intraregional scale, the contribution of land use abandonment was much greater, particularly at low elevations with warmer and drier environmental conditions. The results suggest that the effects of grazing abandonment depend on natural factors such as elevation and climate. Conservation programmes for Nardus grasslands should take into consideration their position along the elevational gradient. In the lower montane zone, management measures should ensure a low nutrient level to restrict the spread of nitrophilous plant species.

A 17-month time course study of human RNA and DNA degradation in body fluids under dry and humid environmental conditions.

Blood, saliva, and semen are some of the forensically most relevant biological stains commonly found at crime scenes, which can often be of small size or challenging due to advanced decay. In this context, it is of great importance to possess reliable knowledge about the effects of degradation under different environmental conditions and to use appropriate methods for retrieving maximal information from limited sample amount. In the last decade, RNA analysis has been demonstrated to be a reliable approach identifying the cell or tissue type of an evidentiary body fluid trace. Hence, messenger RNA (mRNA) profiling is going to be implemented into forensic casework to supplement the routinely performed short tandem repeat (STR) analysis, and therefore, the ability to co-isolate RNA and DNA from the same sample is a prerequisite. The objective of this work was to monitor and compare the degradation process of both nucleic acids for human blood, saliva, and semen stains at three different concentrations, exposed to dry and humid conditions during a 17-month time period. This study also addressed the question whether there are relevant differences in the efficiency of automated, magnetic bead-based single DNA or RNA extraction methods compared to a manually performed co-extraction method using silica columns. Our data show that mRNA, especially from blood and semen, can be recovered over the entire time period surveyed without compromising the success of DNA profiling; mRNA analysis indicates to be a robust and reliable technique to identify the biological source of aged stain material. The co-extraction method appears to provide mRNA and DNA of sufficient quantity and quality for all different forensic investigation procedures. Humidity and accompanied mold formation are detrimental to both nucleic acids.

Consolidation of a Tunisian bioclastic calcarenite: From conventional ethyl silicate products to nanostructured and nanoparticle based consolidants

Mediterranean calcarenite stones are exposed to several weathering processes related to the climate and environment, producing alteration features conducing to loss of cohesion in their structures. Samples of these building materials were collected from the Spanish Fort of Bizerte (Tunisia) to carry out laboratory tests in order to assess the consolidation effect of the nowadays most frequently used products and most innovative consolidation materials based in nanoparticles. Stone specimens were consolidated with the most employed alkoxysilane product (ethyl silicate), with a surfactant-templated novel sol-gel product (that avoids the tendency to crack) and with inorganic products based on calcium hydroxide nanoparticles (Ca(OH)2) and silica nanoparticles (SiO2) under very humid and dry environmental conditions. Samples were characterized by scanning electron microscopy, peeling test, superficial hardness, drilling resistance, water absorption by capillarity and under vacuum, water desorption and spectrophotometry, before and after one month of the application of the products to evaluate their consolidation effect under different environmental conditions. The results show great differences in the consolidation effect and in the changes produced in the physical properties of the substrate after using alkoxysilane products (even nanostructured) or products based in nanoparticles. In the case of alkoxysilane and nanostructured products, especially exposed to high RH conditions, the mechanical properties of the substrate, internal and surface, increase. In both cases a layer on the substrate which occludes the pores is generated maintaining a hydrophobic behavior after one month causing drastic changes in the hydric behavior with visually detectable aesthetic changes. In the case of inorganic nanoparticles, changes in the porosity of the substrate caused by the creation of micropores occur in both cases. In the case of SiO2 nanoparticles, moderate physical changes occur in dry conditions resulting in less shrinkage and color changes. Finally, Ca(OH)2 nanoparticles are the products with the lowest surface and internal consolidation effectiveness which barely change the physical properties of the stone.

Seasonal water relations in four co-existing native shrub species from Northeastern Mexico

ABSTRACTSeasonal xylem water potentials (Ψ, MPa) and their relationship to soil water content and evaporative demand components were studied in the shrub species Acacia amentacea, Celtis ehrenbergiana, Forestiera angustifolia, and Parkinsonia texana var. macra. Predawn (Ψpd) and midday (Ψmd) water potentials were estimated at 15 days intervals, between January 15 and October 30, 2009 using a Scholander pressure bomb at 06:00 h (predawn) and 14:00 h (midday), respectively. During the humid period, Ψpd ranged from −0.30 MPa (C. ehrenbergiana), to −0.90 MPa (P. texana). In contrast, over the driest period, Ψpd varied between −2.18 (P. texana) and −3.94 MPa (F. angustifolia). At midday, P. texana and F. angustifolia showed the highest (−1.14 MPa) and lowest (−3.38 MPa) Ψ values, respectively. Average soil water content accounted for 35 to 70% of the variation in predawn Ψ. Furthermore, both Ψ reflected the environmental conditions, as indicated by typical correlations observed. The studied shrub species exhibited what seem to be different strategies to avoid damage caused by drought. Thus, P. texana behaved rather as an isohydric plant able to deal well with severe, but short periods of drought. Under exceptionally dry environmental conditions, Ψpd undercut Ψmd values. Similar observations have been made by researchers studying plants in dry ecosystems. All studied native species are recommended for reforestation of the Tamaulipan shrublands, although C. ehrenbergiana and F. angustifolia seem to have limited tolerances for extreme water stress.

Airborne characterization of subsaturated aerosol hygroscopicity and dry refractive index from the surface to 6.5 km during the SEAC4RS campaign

AbstractIn situ aerosol particle measurements were conducted during 21 NASA DC‐8 flights in the Studies of Emissions and Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys field campaign over the United States, Canada, Pacific Ocean, and Gulf of Mexico. For the first time, this study reports rapid, size‐resolved hygroscopic growth and real refractive index (RI at 532 nm) data between the surface and upper troposphere in a variety of air masses including wildfires, agricultural fires, biogenic, marine, and urban outflow. The Differential Aerosol Sizing and Hygroscopicity Spectrometer Probe (DASH‐SP) quantified size‐resolved diameter growth factors (GF = Dp,wet/Dp,dry) that are used to infer the hygroscopicity parameter κ. Thermokinetic simulations were conducted to estimate the impact of partial particle volatilization within the DASH‐SP across a range of sampling conditions. Analyses of GF and RI data as a function of air mass origin, dry size, and altitude are reported, in addition to κ values for the inorganic and organic fractions of aerosol. Average RI values are found to be fairly constant (1.52–1.54) for all air mass categories. An algorithm is used to compare size‐resolved DASH‐SP GF with bulk scattering f(RH = 80%) data obtained from a pair of nephelometers, and the results show that the two can only be reconciled if GF is assumed to decrease with increasing dry size above 400 nm (i.e., beyond the upper bound of DASH‐SP measurements). Individual case studies illustrate variations of hygroscopicity as a function of dry size, environmental conditions, altitude, and composition.

Palaeoclimatic conditions in the Late Triassic-Early Jurassic of southern Africa: A geochemical assessment of the Elliot Formation

The Triassic-Jurassic boundary marks a global faunal turnover event that is generally considered as the third largest of five major biological crises in the Phanerozoic geological record of Earth. Determining the controlling factors of this event and their relative contributions to the biotic turnover associated with it is on-going globally. The Upper Triassic and Lower Jurassic rock record of southern Africa presents a unique opportunity for better constraining how and why the biosphere was affected at this time not only because the succession is richly fossiliferous, but also because it contains important palaeoenvironmental clues. Using mainly sedimentary geochemical proxies (i.e., major, trace and rare earth elements), our study is the first quantitative assessment of the palaeoclimatic conditions during the deposition of the Elliot Formation, a continental red bed succession that straddles the Triassic-Jurassic boundary in southern Africa. Employing clay mineralogy as well as the indices of chemical alteration and compositional variability, our results confirm earlier qualitative sedimentological studies and indicate that the deposition of the Upper Triassic and Lower Jurassic Elliot Formation occurred under increasingly dry environmental conditions that inhibited chemical weathering in this southern part of Pangea. Moreover, the study questions the universal validity of those studies that suggest a sudden increase in humidity for the Lower Jurassic record and supports predictions of long-term global warming after continental flood basalt emplacement.

Four decades of land-cover, land-use and hydroclimatology changes in the Itacaiúnas River watershed, southeastern Amazon

Long-term human-induced impacts have significantly changed the Amazonian landscape. The most dramatic land cover and land use (LCLU) changes began in the early 1970s with the establishment of the Trans-Amazon Highway and large government projects associated with the expansion of agricultural settlement and cattle ranching, which cleared significant tropical forest cover in the areas of new and accelerated human development. Taking the changes in the LCLU over the past four decades as a basis, this study aims to determine the consequences of land cover (forest and savanna) and land use (pasturelands, mining and urban) changes on the hydroclimatology of the Itacaiúnas River watershed area of the located in the southeastern Amazon region. We analyzed a multi-decadal Landsat dataset from 1973, 1984, 1994, 2004 and 2013 and a 40-yr time series of water discharge from the Itacaiúnas River, as well as air temperature and relative humidity data over this drainage area for the same period. We employed standard Landsat image processing techniques in conjunction with a geographic object-based image analysis and multi-resolution classification approach. With the goal of detecting possible long-term trends, non-parametric Mann–Kendall test was applied, based on a Sen slope estimator on a 40-yr annual PREC, TMED and RH time series, considering the spatial average of the entire watershed. In the 1970s, the region was entirely covered by forest (99%) and savanna (∼0.3%). Four decades later, only ∼48% of the tropical forest remains, while pasturelands occupy approximately 50% of the watershed area. Moreover, in protected areas, nearly 97% of the tropical forest remains conserved, while the forest cover of non-protected areas is quite fragmented and, consequently, unevenly distributed, covering an area of only 30%. Based on observational data analysis, there is evidence that the conversion of forest cover to extensive and homogeneous pasturelands was accompanied by systematic modifications to the hydroclimatology cycle of the Itacaiúnas watershed, thus highlighting drier environmental conditions due to a rise in the region's air temperature, a decrease in the relative humidity, and an increase in river discharge.

Morphological changes in the spiracles of Anopheles gambiae s.l (Diptera) as a response to the dry season conditions in Burkina Faso (West Africa).

BackgroundSurvival to dry season conditions of sub-Saharan savannahs is a major challenge for insects inhabiting such environments, especially regarding the desiccation threat they are exposed to. While extensive literature about insect seasonality has revealed morphologic, metabolic and physiological changes in many species, only a few studies have explored the responses following exposure to the stressful dry season conditions in major malaria vectors. Here, we explored morphological changes triggered by exposure to dry season conditions in An. gambiae s.l. mosquitoes by comparing females reared in climatic chambers reflecting environmental conditions found in mosquito habitats during the rainy and dry seasons in a savannah area of Burkina Faso (West Africa).ResultsUsing scanning electron microscopy (SEM) and confocal imaging, we revealed significant changes in morphological features of the spiracles in females An. gambiae s.l. exposed to contrasted environmental conditions. Hence, the hairs surrounding the spiracles were thicker in the three species when raised under dry season environmental conditions. The thicker hairs were in some cases totally obstructing spiracular openings. Specific staining provided evidence against contamination by external microorganisms such as bacteria and fungi. However, only further analysis would unequivocally rule out the hypothesis of experimental artifact.ConclusionMorphological changes in spiracular features probably help to limit body water loss during desiccating conditions, therefore contributing to insect survival. Differences between species within the An. gambiae complex might therefore reflect different survival strategies used by these species to overcome the detrimental dry season conditions in the wild.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-015-1289-0) contains supplementary material, which is available to authorized users.

Chemical signals in desert lizards: Are femoral gland secretions of male and female spiny-tailed lizards, Uromastyx aegyptia microlepis adapted to arid conditions?

Many lizards use femoral gland secretions in intraspecific chemical communication, but specific compounds have been identified in only a few species. Chemical composition of secretions may depend on phylogeny, but it may also evolve to maximize efficacy of signals in a given environment. In deserts, the extreme dry and hot environmental conditions are hostile for chemical signals and, therefore, we expected desert lizards to have secretions with highly stable compounds. Using GC–MS, we identified 74 lipophilic compounds in femoral secretions of male and female spiny-tailed lizards, Uromastyx aegyptia microlepis (Fam. Agamidae), from the Qatar desert. Compounds included mainly steroids and fatty acids, but also terpenoids, ketones, tocopherol, aldehydes and alcohols. We found differences between males and females; males had higher proportions of fatty acids and tocopherol, but lower proportions of ketones than females. Contrary to expectations, the most abundant compounds were not stable in the desert climatic conditions at the surface. However, secretions could be rather adapted to microclimatic conditions inside burrows where these lizards spend long periods of time. We suggest that in addition to phylogenetic and environmental characteristics, we should know the ecology of a lizard species before making generalizations on the potential characteristics of its chemical signals.

An Investigation on Turning Hardened Steel Using Different Tool Inserts

Turning of hard materials usually presents poor machinability. However, for high productivity, it is desirable to employ turning of hard materials rather than grinding. In this work, turning of hardened 16MnCrS5 steel with hardness of 43 HRC was explored to judge machining performance with plain and wide-groove-type chip-breaking TiC-coated carbide inserts under dry and wet environmental conditions, different cutting velocity, and feed. Tool wear tests were also done in dry and wet conditions. Satisfactory tool performance was observed under wet condition using TiC-coated plain and wide-groove carbide inserts even at 268 m/min cutting velocity, when dry machining could not be done effectively.

Friction and Wear of GUR 1020 Medical Grade Uhmwpe Polymer at Dry Environmental Condition

In engineering applications when materials start sliding against each other the problem of friction and wear appears. In the case of polymers the friction between them can be attributed to two main mechanisms: deformation and adhesion. One of the important application fields for polymers is the medical engineering. In this field, the UHMWPE polymer is one of the important candidant polymer material. In this investigation, the friction and wear performance of GUR 1020 medical grade UHMWPE polymer under dry sliding conditions is evaluated. The sliding experiments were carried out on a pin-on-AISI stainless steel disc arrangement. Wear tests were carried out under room temperature, 50, 100and 150N load values and at 0.50, 1.0 and 2.0m/s sliding speed conditions. The results show that the coefficient of friction for GUR 1020 medical grade UHMWPE polymer is significantly influenced by applied load, sliding speed values. Furthermore, the coefficient of friction and specific wear rate increases with the increase in applied load and sliding speed values. The specific wear rate values for GUR 1020 medical grade UHMWPE polymer under dry condition is at the order of 8x10-14 m2/N. The friction coefficients vary between 0.12 and 0.20. Finally, the wear mechanism includes abrasive and adhesive processes.

The role of vegetation covers on soil wetting processes at rainfall event scale in scattered tree woodland of Mediterranean climate

Soil water is recognized as the key factor that controls the organization and functioning of dryland ecosystems. However, in spite of its great importance in ecohydrological processes as well as in modelling applications, most of the studies focus on daily or longer timescales, while its dynamics at shorter timescales are very little known. The main objective of this work was to determine the role of vegetation covers (grassland and tree canopy) in the soil hydrological response using measurements with high temporal resolution in evergreen oak woodland with Mediterranean climate. For this, soil water content was measured with capacitive sensors installed in the soil profile at different depths registering continuously with a high time resolution. Three study areas were monitored for two and half hydrological years. Results obtained revealed that rainwater amounts reaching the soil may temporarily be modified by covers according to precipitation properties and antecedent conditions (from dry to wet) before the rain episode. Rainfall amounts triggering a positive soil hydrological response decreased as initial states became drier, being more accentuated below tree canopies. The frequency of re-wetting cycles and the antecedent states seem to be as important or even more than either the duration or the precipitation amount. Therefore, the role of vegetation was more decisive under drier environmental conditions, where events lower than 6 mm and 2 mm never caused soil hydrological response either below tree canopy or grassland, respectively. This is important because initial conditions were independent of seasonality and because more than half of all rainfall events registered amounts smaller than 5 mm. If changes on precipitation patterns turn out in drier conditions, the predominance of such situations could have important ecohydrological consequences in semiarid ecosystems.

Radar Burn Ratio for fire severity estimation at canopy level: An example for temperate forests

Abstract Fires affect wide areas and their effects can be successfully estimated from a range of remote sensing sensors, with synthetic aperture radars (SAR) being of particular interest due to their sensitivity to forest vertical structure, global availability and independence of cloud cover or solar elevation. Previous studies have demonstrated the sensitivity to fire effects of L-band SAR sensors using post-fire datasets and empirical modeling. This study proposed an innovative method for estimating fire severity by combining pre- and post-fire SAR datasets within a change detection framework to compute a novel index, the Radar Burn Ratio (RBR). More importantly, a standardized RBR was developed and tested over seven temperate forest types located on three continents with above ground biomass values ranging from 30 to over 500 t ha− 1. RBR standardization allowed for common thresholds to be defined and subsequently used for estimating the Composite Burn Index (CBI, a measure of fire impact) without the need for a priori information (i.e., in situ data) on local post-fire conditions. The estimation accuracy of the standardized RBR was compared to locally-calibrated empirical models based on field CBI data. The results showed similar estimation errors and a strong agreement with the reference in situ data (i.e., Cohen's weighted kappa > 0.61). The RBR index most sensitive to fire severity was based on the cross-polarized channel applied under dry environmental conditions. Under wet conditions the estimation accuracy was considerably lower. The methods proposed in this study are particularly valuable for rapid fire severity assessments at regional to global scales, requiring only that RBR thresholds be calibrated for a range of environments and that CBI scores be related to fuel consumption for each forest type.

Technical mapping of solar photovoltaic for the Coal City of India

Performance of nine commercial solar photovoltaic (PV) panels from different manufacturers with combination of different manufacturing materials and technologies are studied under the environmental conditions of the Coal City of India. The results give an indication of the comparative performance of different PV technologies under the aforesaid location’s environmental condition which helps to choose the best suitable PV technology for the Coal City of India. This procedure is commonly known as technical mapping of solar PV. Performance of PV panels made of Maxeon Cell Technology, heterojunction with intrinsic thin layer (HIT), mono-crystalline silicon (Mono C-Si), poly-crystalline silicon (Poly C-Si), Micromorph, SCHOTT, amorphous silicon (a-Si), copper indium gallium selenide (CIGS) and cadmium telluride (CdTe) technologies is analysed. Meteorological and PV panel parameters required for the study are collected from National Aeronautics and Space Administration (NASA) renewable energy resource website (Surface Meteorology and Solar Energy) and the data sheets of commercial PV panel manufacturers, respectively. The outcome of this study concludes that modules made of amorphous silicon technology perform better under the typical temperature variant and dry environmental condition of the Coal City of India. The same PV technology is also best suited considering life cycle assessment and global warming impact point of view for the concerned site.