Physicochemical Variations Research Articles

Antibiotic Resistome Biomarkers associated to the Pelagic Sediments of the Gulfs of Kathiawar Peninsula and Arabian Sea

Antibiotic resistance has been one of the most persistent global issue. Specifically, marine microbiomes have served as complex reservoirs of antibiotic resistant genes. Molecular advancements have enabled exploration of the uncultured microbial portion from hitherto difficult to sample niches such as deeper oceans. The Gulfs of Kathiawar Peninsula have been known for their unique properties like extreme tidal variations, different sediment textures and physicochemical variations. Pelagic sediment cores across four coordinates each of the Gulf of Kutch, Gulf of Khambhat and an open Arabian Sea were collected, processed for metagenomic sequencing and assessed for antibiotic and metal resistome. The dominant genes were mostly resistant to macrolides, glycopeptides and tetracycline drugs. Studied samples divided into three clusters based on their resistome with carA, macB, bcrA, taeA, srmB, tetA, oleC and sav1866 among the abundant genes. Samples from creek of Gulf of Kutch and mouth of Gulf of Khambhat were most diverse in resistance gene profile. Biomarkers observed include gyrA mutation conferring resistance gene in the Arabian Sea; Proteobacteria species in Gulf of Kutch and Arabian sea; while Aquificae, Acidobacteria and Firmicutes species in the Gulf of Khambhat. Region-wise differentially abundant 23 genes and 3 taxonomic biomarkers were proposed for antibiotic resistance monitoring.

Robust curcumin-mustard oil emulsions for pro to anti-oxidant modulation of graphene oxide

The compositional flexibility of emulsions, via surfactant and additive choice, has been the major reason for their recognition as tuneable delivery sources for a variety of drugs. In particular, the kinetically stable nanoemulsions (NE) are preferred to minimize the toxicity extents of several poorly hydrophobic drugs through variation in their delivered extents. Inspired by these specialties, we have optimized our curcumin (curc) loaded sodium dodecylsulpahte (SDS) and dodecyl trimethylammonium bromide (DTAB) stabilized mustard oil microemulsions (ME) which catalyzed the pro-oxidant (with ethanol only) to antioxidant graphene oxide (GO) structural expression. The GO was synthesized using wet chemical approach, using ubiquitous graphite flakes as raw material. GO was loaded into 1:1 mixtures of (separately made) SDS and DTAB curc loaded formulations (CLFs). Henceforth, the resultant formulation contained 60% (1:1 SDS and DTAB) CLF mixture and ethanol dispersed GO (@ 1 mg/mL) as the other component. Compared to an insignificant (~47%) free state (while being dispersed in ethanol) DPPH free radical scavenging, the GO dispersed in CLFs enabled (62.47–100.96)% increments in DPPH scavenging, with 94.45% as maximum neutralization extent. The (493.57–3154.95)% particle size increments and (40.64–92.70)% PDI decrements for GO supplemented formulation over SDS and DTAB CLF mixtures, have inferred a wider curc distribution, through the larger GO surface area (SA) and its augmented oxygen enhanced chemical controls. In support, the physicochemical variations, characterized by (1.77–21.23)% γ decrements, (63.56–98.08%) and (68.90–163.22)% η and σ increments, have complemented the dispersion enhancing GO activities. Considering the bioactive nature of curc, these observations predict a prevalence of native curc structure or its enhanced non-covalent interaction controls with GO. Edible nature of mustard oil alongwith frequent inclusion of SDS and DTAB in routine gadgets, propel our formulations as robust media for attaining desired structural activities of functionalized GO derivatives.

Effect of microstructure and initial cell conditions on thermal inactivation kinetics and sublethal injury of Listeria monocytogenes in fish-based food model systems

The development of more accurate predictive models that describe the microbial kinetics of mild thermal treatments of foods requires knowledge concerning the influence of food microstructure and initial cell conditions on foodborne pathogens’ inactivation kinetics. The effect of food microstructure and initial cell conditions on thermal inactivation kinetics and sublethal injury (SI) of Listeria monocytogenes was investigated at 59, 64 and 69°C. Fish-based food model systems with different microstructures, possessing minimal compositional and physicochemical variations, were used. L. monocytogenes growth morphology had no significant influence on thermal inactivation kinetics. A gelled matrix resulted in a lower specific inactivation rate kmax and a higher residual cell population Nres, while the presence of fat droplets resulted in a higherkmaxand did not influenceNres. SI was higher in viscous than in gelled systems and more prominent for cells that were grown inside the matrix. Hence, predictive thermal inactivation models could benefit from the inclusion of factors related to the nature of the food matrix and fat properties. Starting inactivation from cells that were grown inside the matrix, resulted in lower (i.e., fail-safe)kmaxvalues and more uncertainty onNres as compared to starting from cells grown at optimal conditions.

Bacterial community structure and functional diversity in subsurface seawater from the western coastal ecosystem of the Arabian Sea, India

The present study revealed the spatial variability of bacteria in relation to physicochemical variations at four different locations (Diu - DIU, Veraval - VER, Porbandar - POR and Okha - OKH) along the Gujarat coast (Arabian Sea, India). The natural habitat was analyzed for temperature, salinity, pH, total dissolved solids, total organic content, total inorganic content, biological oxygen demand, conductivity and total dissolved oxygen. The lowest salinity and conductivity were observed at the VER site, whereas the highest salinity and conductivity were measured with OKH samples. In contrast, the pH was slightly alkaline at all of the sites. The VER site contained the maximum total dissolved solids (TDS), total carbon (TC), total organic carbon (TOC), and total inorganic carbon (TIC), while OKH showed the maximum dissolve oxygen (DO), biological oxygen demand (BOD), pH, temperature, conductivity, and salinity. The physicochemical characteristics showed that the Gujarat coast is alkaline and has a nutrient heterogeneous nature. Average well color development (AWCD) values, calculated using Biolog EcoPlates, showed that the microbial community from VER contained the highest metabolic activities and could metabolize all 31 substrates, followed by DIU > OKH > POR samples. In contrast, the abundance of the bacterial community, determined by qRT-PCR, was maximum in VER samples, followed by OKH > POR > DIU samples. The Shannon and Simpson indices showed that DIU, POR and OKH seawater clone libraries were more diverse. Furthermore, Chao estimator revealed the high diversity of POR and DIU clone libraries. Interestingly, DIU and OKH did not share any common operational taxonomic units (OTUs), and overall, the maximum bacterial diversity was observed with the POR seawater sample. Moreover, these observations were supported by statistical analysis, such as canonical correspondence analysis (CCA) and principal component analysis (PCA). The molecular phylogeny revealed the dominance of Proteobacteria followed by Firmicutes. Within the Proteobacteria phylum, most of the sequences were affiliated with the Gammaproteobacteria class. In total, about 726 OTUs were observed from all four sites which covers 59.79% DIU, 87.5% VER, 50% POR and 98.83% OKH of samples. This study is the first report to describe physicochemical attributes and the bacterial diversity of the coastal area of Gujarat. The study will provide useful insights about bacterial diversity, distribution, and abundance, as well as their relationships with the habitat.

Experimental Investigation of the Effect of Pre-Bond Contamination with Fingerprints and Ageing on the Fracture Toughness of Composite Bonded Joints

The effect of the pre-bond contamination with fingerprint (FP), both during the production and the application of adhesively bonded patch repairs on composite aircraft parts, and the cumulative effect of fingerprint and hygrothermal ageing on the fracture toughness of carbon fiber reinforced plastic (CFRP) bonded joints are experimentally investigated. To this end, mode I and mode II fracture toughness tests were conducted on FP contaminated coupons and mode II fracture toughness tests on FP contaminated and aged coupons. The artificial FP was supposed to mimic the accidentally applied fingerprints on the CFRP adherent and was applied on the adherent in the size of a human thumb. The two investigated FP formulations consisted of an artificial hand perspiration solution for the production scenario, and of Skydrol hydraulic-oil for the repair scenario. Three levels of contamination with FP were considered for each scenario. The hygrothermal ageing conditions applied until moisture saturation achieved were 70 °C/85% RH. Prior to bonding, the CFRP adherent surfaces were inspected using full-scale monitoring with optically stimulated electron emission (OSEE), an extended nondestructive testing method, in order to analyze the physicochemical variations at the contaminated surface of the adherents before bonding. The ANOVA statistical method was used to assist the evaluation of the results and the deduction or reliable conclusions. The results revealed that the pre-bond FP contamination of the adherents leads to the reduction of the fracture toughness of the CFRP bonded joints. After-bond hygrothermal ageing under the prescribed conditions had no significant influence on the moisture absorption and load carrying capacity of the joint. However, it influenced the bondline integrity as it led to a significant reduction of the fracture toughness of the joint. The effect of the combination of pre-bond contamination and after-bond hygrothermal ageing is more severe than the two separate effects.

The Long and Short of Biodiversity: Cumulative Diversity and Its Drivers

Long-term or cumulative diversity is the biodiversity that accumulates at a site over many generations of community members. Cumulative diversity is likely important to the intrinsic and functional value of ecosystems given the legacies left behind by many species. While its components—average short-term diversity (alpha) and temporal turnover (beta)—have been extensively studied, cumulative diversity itself has not. We therefore examined the environmental and community drivers of cumulative diversity with a novel hierarchical diversity partition. This partition breaks cumulative diversity into short-term, turnover, richness, and evenness components. We applied this framework to 49 tropical rock pool communities, censused over tens to hundreds of organism generations. Results uncovered two environmental regimes that differentially impacted the richness and evenness components of cumulative diversity: Occasional drying events mainly limited richness and reset communities, while less severe physicochemical variations reduced the evenness of communities. These causal pathways amount to differential controls on cumulative diversity; controls that can oppose each other to buffer diversity against change as well as create unexpected trade-offs for managers. We conclude that maintaining diversity at longer timescales requires new analytical tools and an expanded view that can account for its complexity.

Remote sensing and ground based assessment of distribution of land cover parameters inthe catchment area of Wadi el K’sob M’sila (Algeria)

Remote sensing methodology was applied to assess two land cover parameters (elevation and soil moisture) in the first stage.Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) was used to build a map of the water catchment basins within the Wadi El K'sob area. Relative soil moisture for the territory of the Wadi El K'sob catchment area was estimated by using the Sentinel-1/Multispectral Instrument (MSI) and Landsat-8/Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) optical multispectral data. Elevation data of the sampling points range from 398 to 1081 meters above sea level. Soil moisturevaried from 0.2 to 0.37 relative units. The effects of altitude and physico-chemical properties of soil on soil microflora communities in the catchment area of Wadi El K'sob M’sila (Algeria) were investigated in the second stage. The work presented here identified three groups of microorganisms in the soil samples collected in spring 2017from 7 locations situated in the catchment area of Wadi El K'sob M’sila (Algeria) along with 11 physico-chemical characteristics. Statistical tests showed that actinomycetes, fungi and mesophilic bacteria were positively correlated to the altitude. The results revealed that the microflora communities was very dependent on soil physico-chemical characteristics, the main parameters were relative soil moisture, texture, pH, electrical conductivity, organic carbon, organic matter, total nitrogen and available potassium. Generally, the parameters analyzed in this study, indicate a change in the soil microflora community according to the altitudinal and soil physico-chemical variations.

Geochemical and micro-textural fingerprints of boiling in pyrite

Abstract The chemical composition, textures and mineral associations of pyrite provide key information that help elucidate the evolution of hydrothermal systems. However, linking the compositional and micro-textural features of pyrite with a specific physico-chemical process, e.g., boiling versus non-boiling, remains elusive and challenging. In this study we examine pyrite geochemical and micro-textural features and relate these results to pyrite-forming processes at the active Cerro Pabellon Geothermal System (CPGS) in the Altiplano of the northern Chile. We integrate electron microprobe analysis (EMPA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) data with micro-textural observations of pyrite and associated gangue minerals recovered from a ∼500 m long drill core that crosscuts the argillic, sub-propylitic and propylitic alteration zones of the CPGS. Additionally, we carried out a Principal Component Analysis (PCA) in order to inspect and understand the main data structure of the pyrite geochemical dataset. The concentrations of precious metals (Au and Ag), metalloids (As, Sb, Se, Bi and Tl), and base and heavy metals (Cu, Co, Ni and Pb) in pyrite from the CPGS are significant. Among the elements analyzed, As, Cu and Pb are the most abundant with concentrations that vary from a few parts per million (ppm) to wt% levels (up to 4.4 wt% of As, 0.5 wt% of Cu and 0.2 wt% of Pb). Based on contemporaneous gangue mineral associations and textures, the mechanisms of pyrite precipitation in the CPGS were inferred. Pyrite formed during vigorous boiling is characterized by relatively high concentrations of As, Cu, Pb, Ag and Au and lower concentrations of Co and Ni compared to pyrite formed under different conditions. These anhedral to euhedral pyrite grains display zones with a porous texture and abundant mineral micro- to nano-inclusions (mainly galena and chalcopyrite) indicating a formation by rapid crystallization. In contrast, pyrite formed under gentle boiling (more gradual cooling and less abrupt physico-chemical variations than in vigorous boiling) to non-boiling conditions is characterized by a higher concentration of Co and Ni, and relatively low concentrations of As, Cu, Pb, Ag and Au. Texturally, these pyrites form aggregates of euhedral and pristine pyrite crystals with scarce pores and mineral inclusions suggesting formation under steadier physico-chemical conditions. Our results show that pyrite can not only record the chemical evolution of hydrothermal fluids, but can also provide critical information related to physico-chemical process such as boiling and phase separation. Since boiling of aqueous fluids is a common phenomenon occurring in a variety of pyrite-forming environments, e.g., active continental and seafloor hydrothermal systems, and porphyry Cu-epithermal Au-Ag deposits, pyrite compositional and textural features are a valuable complement for discriminating and tracking boiling events in modern and fossil hydrothermal systems.

Physicochemical Quality Evolution of Groundwater from the Area of an Chemical Platform

The most important natural resource which cannot be optimally used and sustained unless its quality is properly assessed, is groundwater. In the present study, the physicochemical variations of groundwater from the area of an chemical platform were determinate. The physicochemical parameters determined for the groundwater were evaluated by comparing the results obtained with the the limits allowed under current legislation. For this study were examining 16 drillings for a period of five years. Water samples were collected quarterly from each sampling point in the study. The physico-chemical quality indicators analyzed for each source were: pH, chlorides, sulfates, bicarbonates, carbonates, sodium, calcium, magnesium, ammonium, filterable residue, suspended matter, mercury and CCO-Mn.Interpretation of physicochemical data revealed that groundwaters studied was neutral to slightly alkaline. The cations such as sodium (Na+) for all groundwaters studied it was in general found above the limit imposed under the laws in vigor in almost all studied drillings except drillings generally located upstream of the industrial platform. The anions such as chlorides (Cl-) exceeded, in general, the limit allowed under current legislation. The filterable residue concentration was observed in all the studied drillings and the parameter such as sulfate (SO42-), were within the limit allowed under current legislation for the most all studied drillings, for the whole period investigated. In general, the sulfate quality indicator exceeds the required limit, for drilling located downstream and in vicinity of the chemical platform.

Effect of Environmental Factors on Cyanobacteria Richness in Some Agricultural Soils

The physicochemical variations of soil, such as temperature, pH, nutrients, and the type of plant cultivation, affect the diversity of cyanobacteria, whether heterocystous or not. The aim of this study was to identify the species of cyanobacteria in a soil and the effect of environmental characteristics on cyanobacteria. Soil samples collected from six different agricultural sites in Al Diwaniyah city/Iraq during September 2016 in the autumn season were analyzed, and the physicochemical characteristics of the samples were measured using approved methods.The results showed significant correlation and differences between cyanobacteria composition, distribution, and physicochemical factors among soil sites. The Agricultural soil was slightly alkaline and moderately saline and contained abundant nutrients, cations and a high percentage of organic matter. All these characteristics influenced the distribution and diversity of cyanobacteria. Ninety-six species were identified, including four heterocystous species represented by Anabaena, Calothrix, Cylnidrospermum, and Nostoc. However, the non-heterocystous were represented by 13 species: Aphanocapsa, Aphanothece, Arthrospira, Chroococcus, Gloeocapsa, Lyngbya, Merismopedia, Microcystis, Microcoleus, Oscillatoria, Phormidium, Schizothrix, and Spirulina. The dominant species of cyanobacteria was Oscillatoria, followed by Phormidium, Chroococcus, Gleocapsa and Lyngbya. The highest value of Shannon’s and Simpson’s diversities were registered in the Ghammas site, which is a paddy field, but the lowest was registered in the Afak site, cultivated with the alfalfa plant. Soil was classified as finely textured with silty clayey characterization, favorable for cyanobacteria growth.

Neoproterozoic tectonothermal evolution of NW India: Evidence from geochemistry and geochronology of granitoids

Neoproterozoic granitoids from the Delhi Fold Belt in NW India record formation and evolution of the marginal orogen in the Rodinia supercontinent. The ca. 976 Ma Moras I-type granites show variable SiO2 (67.15–75.87 wt%) and CaO (1.10–3.24 wt%) and low REE (59–196 ppm). Their spider diagram is characterized by enrichment of Rb, Th and U and depletion of Na and Ta with positive Pb and negative Sr and Ti anomalies. They have positive εNd(t) (+0.41 to +1.40) and εHf (+2.34 to +9.35) and moderate δ18O values (6.48‰ to 7.58‰). These features suggest that the Moras granites were produced by melting of the juvenile mafic curst. However, the ca. 811 Ma Pali and ca. 780 Ma Mirpur A-type granites have high SiO2 (74.42–78.63 wt%), K2O + Na2O (7.74–8.95 wt%) and REE (266–334 ppm). Their spider diagrams are more enriched in Rb, Th and U and depleted in Ba, Sr and Ti. They have lower εNd (−2.28 to +0.84) and εHf values (−2.31 to +8.62) than, but similar δ18O (5.77‰ to 7.01‰) to those of the Moras granites, suggesting that the A-type granites were partial melts of the dehydrated mafic crust in a rift setting. The I- and A-type granites in NW India resulted from physicochemical variations of the lithosphere during evolution of the Rodinia. The Neoproterozoic igneous and sedimentary rocks from the Delhi Fold Belt are well correlated with those from the Jiangnan Fold Belt in South China, suggesting that the two belts probably collected together in the configuration of the Rodinia supercontinent.

Under-Deposit Corrosion (UDC): The Hidden Cause of Major Asset Failures in the Oil and Gas Industry

With the continued need for fossil fuels, even as we enter energy transitions, the extraction of oil and gas from significantly abundant sour fields is increasing globally. Sour i,e, H2S –containing gas environments present several challenges to system integrity, including an accelerated rate of localized corrosion, and potential catastrophic premature failures in fluid handling equipment. This creates a risk to asset integrity, leading to financial losses, and significant risk to both human health and the environment. A major problem in sour systems is ‘underdeposit corrosion (UDC)’ which is a type of extremely rapid, localized attack observed under deposits (in this case typically iron-sulfides); it is extremely difficult to both predict and monitor. The mechanism of both iron sulfide formation and UDC in pipeline is not fully understood: the complex nature of iron sulfides along with the dynamic changes of their physical and chemical properties during the corrosion process entails that multiscale correlative investigations are needed. 1-dimensional artificial pit experiments are developed in order to study localised corrosion with the use of multi-electrode arrays; this allows high-throughput measurements such that different variables can be studied simultaneously. The artificial pit acts as an anode in a three-electrode electrochemical cell, simulating an actively dissolving pit, but with reduced dimensionality that allows quantitative extraction of kinetic data as a function of the various system parameters- essentially the deposit physical and chemical properties. Data on the role of deposit chemistry and morphology on the electrochemical dissolution behaviour are presented, and discussed in terms of a transport-controlled model for pit propagation. Complementary planar (2D) surface experiments were performed under deposits; using this blended approach, both general and localized corrosion can be assessed and related to provide a comprehensive understanding of the overall performance of steel under deposits. The dynamic physicochemical variations (surface morphology and chemical composition) in both metal and deposit are related to the electrochemical findings to explain the metal-deposit interdependent physicochemical interactions. The findings of the study paved the way towards innovating experimental methods for example the use of micro-pH electrodes to provide real-time data on the chemistry inside actively dissolving pits under representative deposits. This study provides insights into the different scenarios of UDC phenomenon and potential protocols to develop monitoring probes for industrial application.

Urban stormwater treatment by a constructed wetland: Seasonality impacts on hydraulic efficiency, physico-chemical behavior and heavy metal occurrence

Urban stormwater affects the general quality of water bodies because of their hydraulic and pollution impacts. Stormwater discharges modify stream water flow and are reported as major source of heavy metals (HMs) in urban streams. Stormwater Constructed Wetlands (SCWs) have been built worldwide to manage stormwater before it is released into hydrosystems. In SCWs, stormwater is stored, evaporated and sometimes infiltrated. Subsequently, the HMs in stormwater can be settled, filtered and bioassimilated by microorganisms. Hence, the efficiency of SCWs in managing stormwater depends on climatic conditions, which change with season. The aim of this study was to investigate the impacts of seasonality on the performance of a 6-year-old constructed wetland made with a pond followed by a vertical flow filter. Hydraulic performance of, physico-chemical behaviour of, and HM mitigation via the SCW were evaluated using over 3 years of monitoring (2015–2017) data. Only 35% of the rain events that occurred in the studied catchment caused a discharge into the pond and 17% into the filter. The SCW was mostly supplied with stormwater in spring and summer and provided peak flow attenuation from 97 to 100% in all seasons. Variations in physico-chemical parameters (temperature, dissolved oxygen, pH, and redox potential) were caused by seasonal and dry/wet weather changes. They were greater in the pond than in the filter, which buffers these variations. The high physico-chemical variations in the pond probably had a deleterious effect on HM storage in the pond sediments. Finally, hydrologic and physico-chemical conditions (antecedent dry period length, pH, redox potential) affected the HM concentrations along the SCW. However, HM removal efficiencies were >97% in all seasons.

Physicochemical Control of the Early Permian Xiangshan Fe-Ti Oxide Deposit in Eastern Tianshan (Xinjiang), NW China

The Xiangshan mafic-ultramafic complex is one of the major Early Permian mafic-ultramafic intrusions in eastern Tianshan (Xinjiang, NW China), and consists of two major intrusive phases. The first intrusive phase is mainly gabbroic rocks hosting ilmenite mineralization, while the second intrusive phase is mainly lherzoilite associated with Ni-Cu sulfide mineralization. The Xiangshan ilmenite orebodies hosted in the Fe-Ti oxide-bearing gabbro occur along the contact between hornblende gabbros and leucogabbros. The hornblende gabbros and Fe-Ti oxide rich gabbros at Xiangshan are newly dated to be Early Permian (280.1 and 279.2 Ma, respectively). Major and trace element compositions of zircons and whole rocks from Xiangshan hornblende gabbro and Fe-Ti oxide gabbro have been measured by in situ excimer laser ablation ICP-MS. Zircon Ce4+/Ce3+ ratios based on lattice-strain model and Ti-in-zircon temperatures of hornblende gabbro and Fe-Ti oxide gabbro of the Xiangshan complex are calculated to evaluate the physicochemical variations during the ilmenite mineralization. Whole-rock geochemistry and zircon trace element geochemistry suggest that Fe-Ti oxide gabbros were formed from a basaltic parent magma which had undergone a transfromation from being H2O-rich to H2O-poor. During the magmatic evolution, primitive, H2O-poor basaltic melts may have been replenished into the system, increasing its solidus temperature and decreasing its oxygen fugacity and H2O contents. This may have supperessed the Ti-rich poikilitic hornblende fractionation and promoted the plagioclase fractionation, which consequently concentrated the ore-forming components in the residual melts and generated the ilmenite mineralization.

Diurnal Variation and Water Quality Parameters of Three Different Ecosystems in Gulf of Mannar, Southeast Coast of India

A study pertaining to diurnal variations of water quality parameters were carried out in three different coastal ecosystems Mandapm jetty (MJ), Seagrass meadows (SG) and coral reef (CR) i.e. sites (site1, site 2 and site 3) of Gulf of Mannar (GoM) for the period 24 hours from the month of September 20 to 21, 2016. The various physicochemical parameters like water temperature, salinity, pH and dissolved oxygen of the different environments are the main factors to influence the water quality of the selected study sites. The water temperature (WT°C) varied from 28.44 to 32.30°C, salinity ranged between 35.89 to 40.28 ppt, pH measured as from 7.98 to 8.48 and dissolved oxygen varied from 3.72 to 8.58 mg/l respectively. The recorded value of chlorophyll a ranged between 0.36 to 1.32 mg/m3 from three sites during the study period. From the three different ecosystems, seagrass ecosystem constantly influences the variation of physicochemical parameters from other two ecosystems. The physicochemical variations of coastal region are including wide range of spatio-temporal variations in selected ecosystems (sites).

Ecological characterization of intertidal rockpools: Seasonal and diurnal monitoring of physico-chemical parameters

Diurnal and seasonal variations in temperature, salinity, oxygen concentration, carbonate chemistry parameters and nutrient concentration were monitored within mid-tidal rockpools on the north-western coast of Brittany, France. We also examined the importance of rockpool physical characteristics (e.g. shore height, surface, volume and depth) on the physico-chemical variability. Rockpool shore height and depth appeared as the main physical factors driving physico-chemical variations. Shallow upper shore rockpools exhibited the largest diurnal and seasonal fluctuations of temperature, oxygen concentration and pHT. Conversely, deeper and lower shore rockpools experienced weaker variations, excepted for salinity and nutrient concentrations. The physico-chemical environment was likely to be strongly influenced by rockpool community composition, especially in summer when rockpools were colonized by dense canopy-forming algae. During the day-time emersion, photosynthesis increased oxygen concentration and pHTbut decreased nutrient concentrations in upper shore rockpools. The increase in rockpool pHT provided an alkaline environment conducive to coralline algal calcification. Conversely, at night, upper shore rockpools presented a strong decrease in oxygen concentration and pHT due to the high community respiration, increasing the dissolution in coralline algae. Therefore, rockpools are characterized by complex interactions between physical and chemical parameters and biological processes. Rockpools appear as suitable environments to examine the physiological processes set up by species to face natural variability, especially in a context of climate change.

Understanding the quantitative role of the binding chain (CH2)n (n=1,2 and 3) on the physicochemical character in the intramolecular reaction: Case of triene-amide

In this study, we will be studied quantitatively the binding chain role and understanding the interactions between diene (D) and dienophile (Dp) fragments in the intra-molecule (IM) and identifying the physicochemical variations of these fragments when passing from the isolated fragment (IF) to the linked fragment (LF) at the intra-molecule using the nucleophilic and electrophilic Fukui functions calculated by DFT (density functional theory) method with the B3LYP hybrid and 6-31G(d,p) basis set level. The results found show that the binding chain has a low contribution to the physicochemical character of the intra-molecule and that his principal role focuses on the transfer of the charge between fragments, the quantitative studies we permit to conclude that the nucleophilic Fukui functions of Diene are remains unchanged in the linked fragment than that in diene (D) of isolated fragment (FD IF ) as (and the electrophilic Fukui function of dienophile is divided almost in half in the linked fragment than that in dienophile (Dp) in isolated fragment as .

Pore fluid salinity effects on physicochemical-compressive behaviour of reconstituted marine clays

It has been well recognized that pore fluid salinity significantly affects physical and mechanical properties of clays. However, how to correlate the pore fluid salinity effects on mechanical behaviour with physicochemical variations induced by pore fluid salinity changes is still pending. This study investigates the changes in liquid limit, oxide compositions and compressibility with pore fluid salinity, based on experimental data obtained from reconstituted specimens of two marine clays in China. It is found that oxide compositions vary little with the change in pore fluid salinity, indicating that no chemical reaction occurs during pore salt changing for the investigated clays. Such a finding means that the pore fluid salinity effects on compression behaviour of reconstituted clays can be attributed to the variations in physical properties. For the investigated marine clays with illite as predominant clay mineral, the void ratio at liquid limit is the crucial physical index of assessing the pore fluid salinity effects on the compression behaviour. The intrinsic compression concept is also introduced to compare the compression behaviour of reconstituted clays with and without pore salt. A quantitative approach is proposed to assess the pore fluid salinity effects on the compression behaviour of marine clays reconstituted at different initial water contents.

Biosimilars to recombinant human FSH medicines: comparable efficacy and safety to the original biologic

Two recombinant follicle-stimulating hormone (rFSH)-bearing similar biological medicines (biosimilars) have been authorized by the European Commission. Biosimilar is a regulatory concept alluding to the evidence-based high-standard comparability studies needed to demonstrate its equivalence to a reference original biologic. Because biosimilar development represents a shift from the long-lasting existing paradigms, a thorough understanding of the science behind it will contribute to helping prescribers make informed treatment choices. Contrary to chemically-synthesized medicines, biologics are subject to an inherent molecular variability. From the experience with original biologics, regulatory authorities have accumulated a wealth of knowledge as to what minor batch-to-batch physicochemical variations may be therapeutically acceptable in a given product. Furthermore, in spite of analytically detectable differences, the two original rFSH-bearing medicines currently on the market share fundamentally the same therapeutic profile. Unlike those original medicines, a biosimilar of an rFSH product and the corresponding reference biologic share essentially the same active pharmaceutical ingredient. They are also administered via the same route, at the same dose, and for the same indications. This article revises the background evidence over which the biosimilarity principle has been built, and highlights the therapeutic potential for follitropin biosimilars in order to reassure physicians on their benefit.

A Proteomic Perspective on the Bacterial Adaptation to Cold: Integrating OMICs Data of the Psychrotrophic Bacterium Exiguobacterium antarcticum B7.

Since the publication of one of the first studies using 2D gel electrophoresis by Patrick H. O’Farrell in 1975, several other studies have used that method to evaluate cellular responses to different physicochemical variations. In environmental microbiology, bacterial adaptation to cold environments is a “hot topic” because of its application in biotechnological processes. As in other fields, gel-based and gel-free proteomic methods have been used to determine the molecular mechanisms of adaptation to cold of several psychrotrophic and psychrophilic bacterial species. In this review, we aim to describe and discuss these main molecular mechanisms of cold adaptation, referencing proteomic studies that have made significant contributions to our current knowledge in the area. Furthermore, we use Exiguobacterium antarcticum B7 as a model organism to present the importance of integrating genomic, transcriptomic, and proteomic data. This species has been isolated in Antarctica and previously studied at all three omic levels. The integration of these data permitted more robust conclusions about the mechanisms of bacterial adaptation to cold.