Characterizing rumen microbiota and CAZyme profile of Indian dromedary camel (Camelus dromedarius) in response to different roughages

In dromedary camels, which are pseudo-ruminants, rumen or C1 section of stomach is the main compartment involved in fiber degradation, as in true ruminants. However, as camels are adapted to the harsh and scarce grazing conditions of desert, their ruminal microbiota makes an interesting target of study. The present study was undertaken to generate the rumen microbial profile of Indian camel using 16S rRNA amplicon and shotgun metagenomics. The camels were fed three diets differing in the source of roughage. The comparative metagenomic analysis revealed greater proportions of significant differences between two fractions of rumen content followed by diet associated differences. Significant differences were also observed in the rumen microbiota collected at different time-points of the feeding trial. However, fraction related differences were more highlighted as compared to diet dependent changes in microbial profile from shotgun metagenomics data. Further, 16 genera were identified as part of the core rumen microbiome of Indian camels. Moreover, glycoside hydrolases were observed to be the most abundant among all Carbohydrate-Active enzymes and were dominated by GH2, GH3, GH13 and GH43. In all, this study describes the camel rumen microbiota under different dietary conditions with focus on taxonomic, functional, and Carbohydrate-Active enzymes profiles.

Flow modelling to quantify structural control on CO2 migration and containment, CCS South West Hub, Australia

In order to reduce uncertainties around CO2 containment for the South West Hub CCS site (Western Australia), conceptual fault hydrodynamic models were defined and numerical simulations were carried out. These simulations model worst-case scenarios with a plume reaching a main compartment-bounding fault near the proposed injection depth and at the faulted interface between the primary and secondary containment interval.The conceptual models incorporate host-rock and fault properties accounting for fault-zone lithology, cementation and cataclastic processes but with no account made for geomechanical processes as the risk of reactivation is perceived as low. Flow simulations were performed to assess cross-fault and upfault migration in the case of plume–faults interaction.Results near the injection depth suggest that the main faults are likely to experience a significant reduction in transmissivity and impede CO2 flow. This could promote the migration of CO2 vertically or along the stratigraphic dip.Results near the interface between the primary and secondary containment intervals show that none of the main faults would critically control CO2 flow nor would they act as primary leakage pathways. CO2 flow is predicted to be primarily controlled by the sedimentological morphology. The presence of baffles in the secondary containment interval is expected to be associated with local CO2 accumulations; additional permeability impacts introduced by faults are minor.Thematic collection: This article is part of the Geoscience for CO2 storage collection available at: https://www.lyellcollection.org/cc/geoscience-for-co2-storage

Nitrogen and phosphorus in cascade multi-system tropical reservoirs: water and sediment

The aim of this research was to analyze the horizontal spatial heterogeneity of both water and superficial sediment quality among and within the reservoirs of the Cantareira System (CS), focusing on concentrations of N and P, attributed to the dumping of raw domestic sewage into water bodies, which is the main cause of water pollution in São Paulo State (Brazil). The CS is a multi-system complex composed of five interconnected reservoirs, with water transported by gravity through 48 km of tunnels and channels. From the last reservoir of the CS, with an output of 33 m3s−1, the water is conducted to a water treatment plant, producing half of the water consumed by 19 million people inhabiting São Paulo city. The upstream reservoirs are more eutrophic than the downstream ones. Data also suggest that the low phytoplankton biomass (ranging from 0.9 to 14.4 μg dm−3) is regulated by the low nutrient availability, mainly of phosphorus (TP ranging from below the detection limit, <9.0 μg dm−3, to 47.3 μg dm−3). For water, the DIN/TP ratios values range from 19 to 380. The upstream reservoirs function as nutrient accumulators and the sediment is the main compartment in which P and N are stored. Although the reservoirs are located in different river basins and are not in sequence along the same river, the results suggest a marked gradient between the reservoirs, with features similar to those of cascade reservoirs. The large volumes flowing through the canals and tunnels could explain the observed pattern. The CS reservoirs can therefore be considered multi-system reservoirs in cascade, constituting a particular case of multi-system reservoirs.

Effect of two Backpack Designs on Cop Displacement and Plantar Force Distribution in Children during Upright Stance

Introduction. Many studies have compared different backpack designs and their influence on the carrier; however, no data referring to school students aged 7-8 years are currently available. Therefore, the aim of the research was to assess the influence of backpack design on centre of pressure (COP) displacement and plantar force distribution in children during an upright stance. Material and methods. Nineteen school students (9 males and 10 females) volunteered for the study. Two Polish backpacks intended for school use were evaluated: backpack A, which had two main compartments, and backpack B, which had one main compartment. The backpack load was composed of books, binders, and regular school equipment. During the measurements, the subjects were asked to look ahead with the head straight and arms at the sides in a comfortable position and to stand barefoot on the F-Scan®sensors (Tekscan, F-Scan®) attached to the force platform (Kistler), carrying a load corresponding to 10% of their body mass. Results. The study found insignificant differences between the two backpack designs. Moreover, COP parameters increased significantly during an upright stance while carrying backpack B in comparison to the empty backpack condition. Additionally, we observed significantly higher values of plantar force distribution in the heel region for the condition without load and insignificantly higher ones for carrying backpack A. Conclusions. The results of the current study suggest that the differences between the two backpack designs are too marginal to be detected through COP displacement. Disturbances in plantar force distribution suggest a lack of posture control and a lower stability of the standing position with a backpack, but these disturbances were significant only when the backpack with one main compartment was used.

Passive Noise Reduction in an Automotive Compartment

Fuel economy, international competition and socioeconomic factors have forced manufacturers to develop lighter automotive vehicles. However, such vehicles are typically more susceptible to noise and vibration problems. The internal sound field in the passenger compartment is affected significantly by the acoustic modal characteristics of the cavity, by the dynamic behaviour of the surrounding structure, and by the nature of the coupling of these two dynamic systems. The purpose of this research is to develop and analyse a new vibroacoustic model containing the main compartment cavity and the luggage compartment cavity. Special attention is placed on the effect of a double walled partition between the main compartment cavity and the luggage compartment. The system is studied using ANSYS finite element (FE) code. The modelling involved shell finite elements for the structure and three-dimensional (3D) acoustic elements for the cavities. The 3D FE modal analysis produced results visualizing the complex picture of acoustic-structure coupling in the lower frequency range (30–200 Hz). It was found that strong coupling between the thin walled structure and the acoustic enclosures exists in the vicinity of any acoustic resonance. The key noise reduction principle examined is the passive application of a characteristic impedance mismatch. Using an FE model, numerical simulations are conducted to study the effect of various design parameters on acoustic transmission. The results show that at least 8 dB reductions in sound pressure level may be achieved with a modest level of vacuum in the double partition between the main cabin and the luggage compartment cavity.

Heavy Metals in Drinking Waters from the Paraiba Do Sul – Guandu River System, Rio De Janeiro State, Brazil

The main goals of the present work are the determination of the critical metals in the Paraiba do Sul - Guandu River System (PSR-GR), and the analysis of tap waters supplied to local cities as well as the city of Rio de Janeiro, to evaluate the metal pollution. Results show that four metals (Pb, Cu, Cr and Zn) out of eight released by the local industrial area are the critical metals in the PSR-GR system. Suspended particles are the main compartment in transporting these metals downstream. Analysis of the performance of tap water treatment plants pointed out the main parameter for these treatment plants is the retention of suspended particles. Iron and manganese had the highest concentrations.