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In recent years, the volcanic–plutonic relationship has been a contentious topic among researchers. Based on this issue, they have delved deeper into the constraints of magma reservoir pressure and H2O on pre-eruptive melt accumulation and migration. We selected granodiorite, tonalite, and rhyolite in the Dehailonggang volcanic–plutonic complex to investigate the volcanic–plutonic connection and constraints of reservoir pressure and H2O on the pre-eruptive melt accumulation and migration in water-rich systems. Granodiorite, tonalite, and rhyolite exhibit temporal–spatial similarities (247 Ma) and the same magmatic origin consisting of ca. 75–80% enriched mantle materials mixed with ca. 20–25% lower crustal materials. TESCAN integrated mineral analyzer (TIMA) shows that both granodiorite and tonalite display a typical cumulate texture. The bulk–rock compositional complementary of the granodiorite, tonalite, and rhyolite, coupled with in situ geochemical signatures of feldspars and zircons, feldspar CSD, and rhyolite–MELTS modeling, indicate that (1) the granodiorite represents the crystal cumulate formed after crystal–melt phase separation of the original mush (OM) in the magma reservoir; (2) the interstitial melt of the OM was extracted, migrated, and ultimately erupted as the rhyolite; (3) the tonalite serves as an intermediate product resulting from the phase separation from the OM to the rhyolite. Rhyolite–MELTS modeling reveals that in water-rich environments, an increase in reservoir pressure (prior to reaching overpressure threshold) can lead to a reduction in melt viscosity. This, in turn, accelerates mechanical compaction and phase separation processes, ultimately shortening the pre-eruptive melt aggregation timescale. In contrast, it is noteworthy that H2O has a relatively minor influence on phase separation in such water-rich systems (> 4 wt. %). This study demonstrates the volcanic–plutonic genetic coupling and highlights the significance of reservoir pressure in controlling the dynamics of pre-eruptive melt within water-rich systems. [ABSTRACT FROM AUTHOR]

The Lianzigou deposit, which has an Au–Te paragenetic association, is hosted in plagioclase gneiss of the Qincanggou Formation in the Taihua Group in the Xiaoqinling region, central China. This quartz vein-type Au deposit comprises native Au and a variety of tellurides. The latter include calaverite (AuTe2), krennerite (Au3AgTe8), petzite (Au3AgTe2), hessite (Ag2Te), melonite (NiTe2), and altaite (PbTe). Four stages have been recognized in this deposit: stage I consists of K-feldspar and quartz; stage II is of milky quartz veins accompanied by coarse-grained disseminated and lumps of pyrite with weak Au mineralization; stage III is composed mainly of Au, tellurides, and sulfides; and stage IV is characterized by abundant carbonate and quartz. Based on mineral assemblage and thermodynamic data, we estimated the physicochemical conditions of the main metallogenic stages. Based on thermodynamic modelling, the physicochemical conditions of Au–Ag–Te mineral associations were estimated. The Au–Ag–Te minerals from stage III formed mainly under conditions of logƒO2 = −43.15 to −33.31, logƒH2S = ~−9.29, pH < 7, logfTe2 = −10.6 to −9.8 and logαAu+/αAg+ = −7.2 to −6.5. In contrast, the physicochemical conditions of stage II were higher, specifically pH (8.3–8.5) and logƒO2 (−34.90−31.96). In the ore-forming fluids of the Lianzigou deposit, the dominant Au species was Au(HS)2− while the dominant Te species were HTe−(aq) and Te22−(aq). Moreover, the Au–Ag–Te metal associations in the Lianzigou Au deposit were derived from mantle materials related to lithospheric thinning of the eastern North China craton in the Early Cretaceous under an extensional tectonic system. [ABSTRACT FROM AUTHOR]

The La'erma and Qiongmo Au–Se deposits are characterized by a paragenetic Au–Se association hosted in the siliceous formation of the Cambrian Taiyangding Group in the western Qinling Orogen, central China. The La'erma and Qiongmo Au–Se deposits, which are considered to be the Carlin gold deposits, comprise a variety of selenides, native gold, and stibnite coexisting with baryte. Four stages have been recognized: sage I comprises pyrite and quartz with minor stibnite; stage II is composed mainly of sulfides; stage III is composed mainly of selenides; and stage IV is dominated by quartz–baryte–dickite. Stages II and III are the main metallogenic stages. Based on changes in mineral assemblages, combined with fluid inclusions and thermodynamic data, we evaluated the physicochemical conditions of the main metallogenic stages. The logfS2 values of ore-forming fluids at stage II ranged between −10.44 and −14.60 with logfSe2 being less than −10.70. Comparably, during stage III, which is characterized by numerous selenides, the logfS2 and logfSe2 ranged from −7.13 to −12.20 and −13.98 to −8.82, respectively. The occurrence of baryte during the mineralization suggests a consistently oxidizing condition, which can effectively remove Au from fluids. More importantly, this study emphasizes that the oxidizing condition was only a fundamental prerequisite for the deposition of selenides, and a high ∑Se/S ratio of the fluid ultimately controlled the precipitation of selenides. In the La'erma and Qiongmo deposits, intense water–rock reactions occurred as ore-forming fluids flowed into the Se-rich siliceous formations, resulting in an increase in the ∑Se/S ratio of the fluid and in the precipitation of selenides. [ABSTRACT FROM AUTHOR]

Oil palm processing generates substantial waste materials rich in organic content, posing various environmental challenges. Anaerobic digestion (AD), particularly for palm oil mill effluent (POME), offers a sustainable solution, by converting waste into valuable biomethane for thermal energy or electricity generation. The synergistic activities of the AD microbiota directly affect the biomethane production, and the microbial community involved in biomethane production in POME anaerobic digestion has been reported. The composition of bacterial and archaeal communities varies under different substrate and physicochemical conditions. This review discusses the characteristics of POME, explores the microbial members engaged in each stage of AD, and elucidates the impacts of substrate and physicochemical conditions on the microbial community dynamics, with a specific focus on POME. Finally, the review outlines current research needs and provides future perspectives on optimizing the microbial communities for enhanced biomethane production from oil palm wastes. [ABSTRACT FROM AUTHOR]

The Lianzigou deposit, which has an Au–Te paragenetic association, is hosted in plagioclase gneiss of the Qincanggou Formation in the Taihua Group in the Xiaoqinling region, central China. This quartz vein-type Au deposit comprises native Au and a variety of tellurides. The latter include calaverite (AuTe2), krennerite (Au3AgTe8), petzite (Au3AgTe2), hessite (Ag2Te), melonite (NiTe2), and altaite (PbTe). Four stages have been recognized in this deposit: stage I consists of K-feldspar and quartz; stage II is of milky quartz veins accompanied by coarse-grained disseminated and lumps of pyrite with weak Au mineralization; stage III is composed mainly of Au, tellurides, and sulfides; and stage IV is characterized by abundant carbonate and quartz. Based on mineral assemblage and thermodynamic data, we estimated the physicochemical conditions of the main metallogenic stages. Based on thermodynamic modelling, the physicochemical conditions of Au–Ag–Te mineral associations were estimated. The Au–Ag–Te minerals from stage III formed mainly under conditions of logƒO2 = −43.15 to −33.31, logƒH2S = ~−9.29, pH < 7, logfTe2 = −10.6 to −9.8 and logαAu+/αAg+ = −7.2 to −6.5. In contrast, the physicochemical conditions of stage II were higher, specifically pH (8.3–8.5) and logƒO2 (−34.90−31.96). In the ore-forming fluids of the Lianzigou deposit, the dominant Au species was Au(HS)2− while the dominant Te species were HTe−(aq) and Te22−(aq). Moreover, the Au–Ag–Te metal associations in the Lianzigou Au deposit were derived from mantle materials related to lithospheric thinning of the eastern North China craton in the Early Cretaceous under an extensional tectonic system.

The La’erma and Qiongmo Au–Se deposits are characterized by a paragenetic Au–Se association hosted in the siliceous formation of the Cambrian Taiyangding Group in the western Qinling Orogen, central China. The La’erma and Qiongmo Au–Se deposits, which are considered to be the Carlin gold deposits, comprise a variety of selenides, native gold, and stibnite coexisting with baryte. Four stages have been recognized: sage I comprises pyrite and quartz with minor stibnite; stage II is composed mainly of sulfides; stage III is composed mainly of selenides; and stage IV is dominated by quartz–baryte–dickite. Stages II and III are the main metallogenic stages. Based on changes in mineral assemblages, combined with fluid inclusions and thermodynamic data, we evaluated the physicochemical conditions of the main metallogenic stages. The logfS2 values of ore-forming fluids at stage II ranged between −10.44 and −14.60 with logfSe2 being less than −10.70. Comparably, during stage III, which is characterized by numerous selenides, the logfS2 and logfSe2 ranged from −7.13 to −12.20 and −13.98 to −8.82, respectively. The occurrence of baryte during the mineralization suggests a consistently oxidizing condition, which can effectively remove Au from fluids. More importantly, this study emphasizes that the oxidizing condition was only a fundamental prerequisite for the deposition of selenides, and a high ∑Se/S ratio of the fluid ultimately controlled the precipitation of selenides. In the La’erma and Qiongmo deposits, intense water–rock reactions occurred as ore-forming fluids flowed into the Se-rich siliceous formations, resulting in an increase in the ∑Se/S ratio of the fluid and in the precipitation of selenides.

The subject of this work was supergene uranium mineralization and the YREE concentrations within. YREE differentiation patterns were used to recreate the prevailing crystallization conditions of abandoned mine dumps in Kromnów, Kopaniec, and Radoniów, located in the Izera Metamorphic Complex, Sudetes Mts. The collected samples were investigated using PXRD, SEM-EDS, and EPMA. YREE concentrations were measured using LA-ICP-MS. The secondary uranium mineralization from these locations consists of phosphates (meta-autunite, meta-torbernite, metauranocircite-I, saleéite, bassetite, phosphuranylite), arsenates (zeunerite), silicates (uranophane, sklodowskite), and uranyl hydroxides (likely becquerelite). Moreover, in Radoniów, phosphuranylite was found; it had not been found in Poland previously. Uranyl mineral assemblages indicate the diversity of chemistry of their mother solutions and suggest their weakly acidic character. The YREE content in secondary uranium minerals also reflects the pore solutions' chemistry variation. The negative Y anomaly is observed in all uranyl phases. Similar behavior of Sm is also noted, excluding metatorbernite and torbernite. Among the uranyl minerals studied, only metatorbernite from Kromnów showed a positive Nb anomaly, which was probably related to proximity to weathering in YREE-breeding phases. Nevertheless, the YREE and chemical results suggest that this mineralization originated from the oxidizing solutions generated during the weathering of primary hydrothermal mineralization. In order to better understand the weathering zones in these locations, more detailed studies on pore solution chemistry are needed. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are widespread ecological contaminants. These are produced as a result of diverse natural and anthropogenic activities. Phenanthrene is a low molecular weight PAH and is found prominently around the petrochemical contaminated sites. The increasing environmental concentration of phenanthrene is a threat to the ecosystems and their natural functioning. The present study developed a phenanthrene degrading bacterial consortium NS-PAH-2015-PNP-5 from the petrochemical contaminated soil near the Indian Oil Corporation Limited (IOCL) refinery, Panipat (India). The sample soil's pH, EC, TOC, and phenanthrene concentrations were 7.9, 1.81dS/m, 4.2%, and 19.7 mg/kg, respectively. Results from the 16S rRNA metagenome analysis of the consortium NS-PAH-2015-PNP-5 have shown an overwhelming population of Proteobacteria and Pseudomonas spp. at the respective phylum and species diversity. Response surface methodology (RSM) of statistical optimization tool 'Design-Expert' was used to optimize the physicochemical conditions for the phenanthrene biodegradation study. In the experiment, three factors, including temperature, pH, and concentration of phenanthrene, were optimized against the single response phenanthrene degrading efficiency (%). The gas chromatographic analysis results showed that a phenanthrene degrading efficiency of 89% was obtained at optimized physicochemical conditions (i.e., 35 °C temperature, pH 7.3, and 869 ppm concentration of phenanthrene) after 7 days of incubation of NS-PAH-2015-PNP-5 at a constant shaking rate of 100 rpm. Bacterial consortium NS-PAH-2015-PNP-5 having a foremost population of phylum Proteobacteria, was developed from the petrochemical contaminated soil. A synergistically improved rate of phenanthrene biodegradation by NS-PAH-2015-PNP-5 was achieved at optimized physicochemical conditions using the Design-expert. [ABSTRACT FROM AUTHOR]

This study assessed the air quality and physicochemical conditions of soils and water of Ogbe-Okwe gully in Ukwu-Nzu, Delta State of Nigeria. Air quality after analysis with AeroQual Series 500 Air Sampler showed that Total Suspended Particulate ranged from 15.43 - 28.55 µg/m3, Nitrogen dioxide (0.00 ± 0.0 - 0.01 ± 0.0 µg/m3), Sulphur dioxide (0.00 ± 0.0 - 0.27 ± 0.0 µg/m3), Ozone (0.00 ± 0.0 - 0.01 ± 0.0 µg/m3), Volatile Organic Compounds (0.010 ± 0.0 - 0.61 ± 0.0 µg/m3), Carbon monoxide (0.010 ± 0.0 - 0.01 ± 0.0 µg/m3) and Methane (0.010 ± 0.0 - 0.01 ± 0.0 µg/m3). Physicochemical characteristics of soils samples showed that clay ranged from 24.00 ± 1.92 - 36.00 ± 2.96 %, silt (24.00 ± 1.92 - 33.00 ± 2.83 %), sand (33.00 ± 2.83 - 51.00 ± 3.89 %). pH ranged from 6.70 ± 0.50 - 7.88 ± 0.93, organic matter (0.91 ± 0.37 - 2.00 ± 1.00 %), organic carbon (0.51 ± 0.25 - 0.89 ± 0.37 %) and total nitrogen (0.01 ± 0.00 - 0.05 ± 0.00 %). Electrical conductivity ranged from 4.12 ± 1.45 - 4.81 ± 0.36 µS/cm, available phosphorus (150.00 ± 5.00 - 180.00 ± 5.74 mg/kg), total exchangeable bases (1.60 ± 0.42 - 1.99 ± 0.69 cmol/kg), calcium (1.20 ± 0.15 - 1.22 ± 0.17 mg/kg), magnesium (0.40 ± 0.00 - 0.51 ± 0.10 mg/kg), sodium (0.02 ± 0.00 - 0.05 ± 0.00 mg/kg) and potassium (0.04 ± 0.03 - 0.08 ± 0.00 mg/kg). In soil samples, cadmium values ranged from 0.16±0.13 - 0.30±0.13mg/kg, Lead (1.26 ± 0.33 - 3.50 ± 0.51mg/kg), Zinc (25.12 ± 2.82 - 79.02 ± 3.29 mg/kg), Copper (27.89 ± 2.49 - 63.08 ± 3.68 mg/kg), Iron (191.16 ± 5.07 - 212.16 ± 5.92 mg/kg) and Manganese (10.80 ± 0.49 - 18.00 ± 0.81 mg/kg). The results obtained from this study showed high levels of heavy metals. It is very necessary for government to enact very strict laws that would help minimize the adverse effect of these activities. [ABSTRACT FROM AUTHOR]

This article discusses the stages and physicochemical conditions of polymetallic deposits formation in the Southwestern Karamazar, Northern Tajikistan. The Takeli, Kuruksay, and Kansay ore fields are considered here as an example. The data obtained show that these ore fields are all characterized by the following four stages of hydrothermal ore formation: 1) sulfide, 2) carbonate, 3) quartz-sulfide, and 4) carbonate-barite-fluorite. In the first stage, the mineral formation occurred at the temperature of 450–300 ?C from mainly calcium bicarbonate and calcium sulfate-sodium solutions. The second calcite stage of mineralization occurred at the temperature of 360–160 ?C with a paleotemperature gradient of 14 ?C/100 m. The composition of ore-forming fluids was sulfate-chloride-calcium-sodium-magnesium. The products of the third stage formed in the wide temperature range of 350–90 ?C from predominantly sulfate and hydrocarbonate solutions with a low content of chlorine anions. The main cations were sodium, calcium, and magnesium. The paleotemperature gradient was 10–12 ?C/100 m. The fourth stage proceeded at the temperature of 180–115 ?C from solutions of mainly bicarbonate-calcium composition and low content of chlorine, sulfate ion, sodium, and potassium.

This study assessed the air quality and physicochemical conditions of soils and water of Ogbe-Okwe gully in Ukwu-Nzu, Delta State of Nigeria. Air quality after analysis with AeroQual Series 500 Air Sampler showed that Total Suspended Particulate ranged from 15.43 - 28.55 µg/m3, Nitrogen dioxide (0.00 ± 0.0 - 0.01 ± 0.0 µg/m3), Sulphur dioxide (0.00 ± 0.0 - 0.27 ± 0.0 µg/m3), Ozone (0.00 ± 0.0 - 0.01 ± 0.0 µg/m3), Volatile Organic Compounds (0.010 ± 0.0 - 0.61 ± 0.0 µg/m3), Carbon monoxide (0.010 ± 0.0 - 0.01 ± 0.0 µg/m3) and Methane (0.010 ± 0.0 - 0.01 ± 0.0 µg/m3). Physicochemical characteristics of soils samples showed that clay ranged from 24.00 ± 1.92 - 36.00 ± 2.96 %, silt (24.00 ± 1.92 - 33.00 ± 2.83 %), sand (33.00 ± 2.83 - 51.00 ± 3.89 %). pH ranged from 6.70 ± 0.50 - 7.88 ± 0.93, organic matter (0.91 ± 0.37 - 2.00 ± 1.00 %), organic carbon (0.51 ± 0.25 - 0.89 ± 0.37 %) and total nitrogen (0.01 ± 0.00 - 0.05 ± 0.00 %). Electrical conductivity ranged from 4.12 ± 1.45 - 4.81 ± 0.36 µS/cm, available phosphorus (150.00 ± 5.00 - 180.00 ± 5.74 mg/kg), total exchangeable bases (1.60 ± 0.42 - 1.99 ± 0.69 cmol/kg), calcium (1.20 ± 0.15 - 1.22 ± 0.17 mg/kg), magnesium (0.40 ± 0.00 - 0.51 ± 0.10 mg/kg), sodium (0.02 ± 0.00 - 0.05 ± 0.00 mg/kg) and potassium (0.04 ± 0.03 - 0.08 ± 0.00 mg/kg). In soil samples, cadmium values ranged from 0.16±0.13 - 0.30±0.13mg/kg, Lead (1.26 ± 0.33 - 3.50 ± 0.51mg/kg), Zinc (25.12 ± 2.82 - 79.02 ± 3.29 mg/kg), Copper (27.89 ± 2.49 - 63.08 ± 3.68 mg/kg), Iron (191.16 ± 5.07 - 212.16 ± 5.92 mg/kg) and Manganese (10.80 ± 0.49 - 18.00 ± 0.81 mg/kg). The results obtained from this study showed high levels of heavy metals. It is very necessary for government to enact very strict laws that would help minimize the adverse effect of these activities.

The opportunistic fungal pathogens belonging to the Candida haemulonii complex and the phylogenetically related species Candida auris are well-known for causing infections that are difficult to treat due to their multidrug-resistance profiles. Candida auris is even more worrisome due to its ability to cause outbreaks in healthcare settings. These emerging yeasts produce a wide range of virulence factors that facilitate the development of the infectious process. In recent years, the aggregative phenotype has been receiving attention, as it is mainly associated with defects in cellular division and its possible involvement in helping the fungus to escape from the host immune responses. In the present study, we initially investigated the aggregation ability of 18 clinical isolates belonging to the C. haemulonii species complex (C. haemulonii sensu stricto, C. duobushaemulonii, and C. haemulonii var. vulnera) and C. auris. Subsequently, we evaluated the effects of physicochemical factors on fungal aggregation competence. The results demonstrated that cell-to-cell aggregation was a typically time-dependent event, in which almost all studied fungal isolates of both the C. haemulonii species complex and C. auris exhibited high aggregation after 2 h of incubation at 37 °C. Interestingly, the fungal cells forming the aggregates remained viable. The aggregation of all isolates was not impacted by pH, temperature, β-mercaptoethanol (a protein-denaturing agent), or EDTA (a chelator agent). Conversely, proteinase K, trypsin, and sodium dodecyl sulfate (SDS) significantly diminished the fungal aggregation. Collectively, our results demonstrated that the aggregation ability of these opportunistic yeast pathogens is time-dependent, and surface proteins and hydrophobic interactions seem to mediate cell aggregation since the presence of proteases and anionic detergents affected the aggregation capability. However, further studies are necessary to better elucidate the molecular aspects of this intriguing phenomenon.

The subject of this work was supergene uranium mineralization and the YREE concentrations within. YREE differentiation patterns were used to recreate the prevailing crystallization conditions of abandoned mine dumps in Kromnów, Kopaniec, and Radoniów, located in the Izera Metamorphic Complex, Sudetes Mts. The collected samples were investigated using PXRD, SEM-EDS, and EPMA. YREE concentrations were measured using LA-ICP-MS. The secondary uranium mineralization from these locations consists of phosphates (meta-autunite, meta-torbernite, metauranocircite-I, saleéite, bassetite, phosphuranylite), arsenates (zeunerite), silicates (uranophane, sklodowskite), and uranyl hydroxides (likely becquerelite). Moreover, in Radoniów, phosphuranylite was found; it had not been found in Poland previously. Uranyl mineral assemblages indicate the diversity of chemistry of their mother solutions and suggest their weakly acidic character. The YREE content in secondary uranium minerals also reflects the pore solutions’ chemistry variation. The negative Y anomaly is observed in all uranyl phases. Similar behavior of Sm is also noted, excluding metatorbernite and torbernite. Among the uranyl minerals studied, only metatorbernite from Kromnów showed a positive Nb anomaly, which was probably related to proximity to weathering in YREE-breeding phases. Nevertheless, the YREE and chemical results suggest that this mineralization originated from the oxidizing solutions generated during the weathering of primary hydrothermal mineralization. In order to better understand the weathering zones in these locations, more detailed studies on pore solution chemistry are needed.

[Display omitted] • Three biomass concentrations were tested for bead-milling: 90, 60 and 30 g/L. • The maximum amount of proteins was released after 4 min of bead-milling. • A maceration of diluted ground biomass allowed better soluble proteins recovery. • The best scenario limiting energy consumption led to 12 % proteins recovery. • Pigments were separated from soluble proteins by membrane filtration PES0.1 μm. Chlorella vulgaris proteins show high potential for food applications. The challenge of biorefinery is to choose the best processes coupling which can ensure the integrity of the molecules and limit energy consumption. This study aimed at understanding the impact of biomass concentration and physicochemical conditions during cell disruption, on the whole process (bead milling (BM), centrifugation, microfiltration). The best scenario tested (BM: 60 g/L DW , 10 °C, lysate dilution: 30 g/L DW , pH 7, 20 °C before centrifugation and filtration of the supernatant at a volume reduction ratio VRR = 3) allowed a soluble protein recovery ηS = 12 % with a limited energy consumption of 10 kW h/g protein. Coupling BM at 90 g/L DW , pH 7, a dilution at 20 °C, with NaCl 0.1 M at 30 g/L DW and filtration at VRR = 20 would lead to ηS>25 %. The final soluble proteins contained no green pigment; their purity increased from 5 % in the raw biomass to 22 % in the permeate. [ABSTRACT FROM AUTHOR]

Abstract This study was an attempt to understand the factors influencing the heavy metal distribution in polluted fluvial system sediments. Various biogeochemical processes and anthropogenic factors were playing an important role in altering the concentration of heavy metals in the sediments. This paper has two objectives: The first one is to investigate the effect of the variation in the physicochemical conditions on the speciation of trace elements trapped in the sediments of the Sebou River. The second one is to study the kinetics mobilization of these heavy metals. Batch resuspension experiments were conducted in order to investigate the release of heavy metals from a polluted anoxic sediment submitted to different physicochemical conditions variations. It has been revealed that in oxygenated environment, sediments were oxidized which cause the release of some heavy metals, but their concentrations, as dissolved phase, were sustained constant or were increased with time. However, in acidic and anaerobic environment, most of the metallic trace elements were released together with the iron and the manganese, but some of these elements like chromium were precipitated. However, some of other elements were maintained in solution, which represents a real human health risk.

We establish the physicochemical conditions required for the creation of multicomponent Nb–Ti–Al–X (X – Cr, Zr, Mo, Sr) niobium alloys with improved characteristics of high-temperature strength, heat resistance, and technological efficiency. The conclusions are based on the relationship between the physical properties of alloying elements, enthalpy of mixing, compositions of alloys, and the diagrams of state of the components with specific features of their crystallization caused by alloying. [ABSTRACT FROM AUTHOR]

Nanomedicine is an interdisciplinary approach that involves toxicology and other medicinal applications. Gold nanoparticles (AuNPs) may serve as a promising model to address the size and shape‐dependent biological response because they show good biocompatibility. This study is to prepare phytosynthesis AuNPs from ten different Cassia sp. Among them, the aqueous leaf extract of C. roxburghii produced greater efficient and stable AuNPs. The AuNPs were optimised for different physicochemical conditions. Highly stable AuNPs were synthesised at pH 7.0, 37°C, 1.0 ml of C. roxburghii leaf extract and 1.0 mM concentration of HAuCl4 with the particle size of ∼50 nm and these AuNPs were stable up to 12 months. To determine the safety profile of AuNPs in‐vivo, the nanoparticles were injected intravenously into male Wistar albino rats in varying dosages. The authors noticed no significant difference in body weights, haematological and biochemical parameters and the histopathological sections of all vital organs. Highest accumulation was seen in spleen and least in brain. The authors' results show that the AuNPs were biocompatible and did not produce any adverse or abnormalities in‐vivo. The implications of the bioaccumulation of AuNPs need to be further studied to rule out any adverse effects on long‐term exposure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pyrite contains high Cu, Zn, Au, Ag, Pb, and Sb contents in the massive orebody. • Chalcopyrite is enriched in Ag, Zn, Se, Sn, and Cd, relatively poor in In and Ga. • Iron, Mn, Ag, Se, In, Ge, and Ga are present as lattice in sphalerite. • Thermochemical sulfate reduction is a key factor for sulfur isotope fractionation. • Trace element profiles of sulfides are robust indicator for VMS system formation. The Early Paleozoic arc-hosted volcanogenic massive sulfide (VMS) deposits in the Kalatag arc are well-known for their well-preserved and high-grade Cu–Zn sulfide mineralization in the East Tianshan. Unfortunately, there is a puzzle on the ore-forming fluid and metal source as well as physicochemical condition of metallogenic process of these arc-hosted VMS Cu–Zn deposits. The Huangtupo was firstly reported Early Paleozoic arc-hosted VMS Cu–Zn deposit (300Kt@1.49 % Cu; 280Kt@3.51 % Zn) in the East Tianshan. In order to better recognize the physicochemical condition and formation processe of arc-hosted VMS deposits, this research takes the Huangtupo deposit as an example, combining the microstructure, in-situ sulfur isotope and trace element composition of multistage sulfides to conduct a comprehensive study. In the Huangtupo deposit, the overall mineralization process is divided into syndepositional mineralization stage, hanging-wall massive mineralization stage and channel hydrothermal stage according to the main mineral interpenetration relationship and horizon relationship. Pyrite can be divided into five types in the Huangtupo Cu–Zn deposit: 1) subhedral to anhedral pyrite in the silicious exhalite (Py1); 2) colloform pyrite in the hanging-wall massive pyrite + barite + sphalerite zone (Py2); 3) subhedral pyrite in the hanging-wall massive pyrite + chalcopyrite + sphalerite ± magnetite zone (Py3); 4) fine-grained (or disseminated) pyrite in the footwall pyrite + chalcopyrite + sphalerite stage (Py4); 5) euhedral pyrite in the footwall quartz + pyrite + chalcopyrite stage (Py5). Two types of chalcopyrite are identified, including hanging-wall massive chalcopyrite (Ccp1) and footwall stockwork chalcopyrite (Ccp2). In addition, three generations of sphalerite could be identified, namely (1) hanging-wall massive pyrite + barite + sphalerite zone (Sp1); (2) hanging-wall massive pyrite + chalcopyrite + sphalerite ± magnetite zone (Sp2); and (3) footwall pyrite + quartz + sphalerite + chalcopyrite stage (Sp3). In the upper massive orebody, LA–ICP–MS in-situ microanalysis shows that pyrite is enriched in Cu, Zn, Au, Ag, Pb, Sb, and Tl, while it is poor in Co, Ni, Se, Te, Ti, and Sn, indicating that it was formed in a metal-rich, medium–high temperature and more oxidizing hydrothermal environment. By contrast, pyrite from the footwall stockwork orebody contains low Au, Ag, Cu, Zn, Pb, Sb, Tl and high Co, Se, Te, Ti content, indicating that it is formed in the hydrothermal environment with a high temperature, reduction and trace metal deficit signature. Trace element compositions of sphalerite suggest that Fe, Mn, Ag, Se, In, Ge, and Ga are present as lattice. By contrast, Sn, Pb, Tl, and Bi are present as mineral microinclusions. The mineralization temperature is determined by sphalerite geothermometer (GGIMFis) and shows a decreasing trend from footwall stockwork mineralization to hanging-wall massive mineralization. Comparing with sphalerite, chalcopyrite is enriched in Ge, Ag, Zn, Se, Sn, and Cd, relatively poor in In and Ga. The integrated in situ sulfur isotopic (δ34S) composition and trace metal content of sulfides suggest that ore-forming material is most likely derived from a combination of host volcanics and seawater. In addition, the thermochemical sulfate reduction is also a key factor affecting sulfur isotope fractionation. Overall, the trace element compositions of multistage sulfides are robust monitor of the complex hydrothermal process and effectively reconstruct the metal enrichment process during the formation of arc-hosted VMS mineralization system. [ABSTRACT FROM AUTHOR]

The Dongping gold deposit is located near the center of the northern margin of the North China Craton. It is hosted in the Shuiquangou syenite and characterized by large amounts of tellurides. Numerous studies have addressed this deposit; the mineral paragenesis and ore‐forming processes, however, are still poorly studied. In this contribution, a new mineral paragenesis has been evaluated to further understand ore formation, including sulfides (pyrite, chalcopyrite, galena, sphalerite, molybdenite, and bornite), tellurides (altaite, calaverite, hessite, muthmannite, petzite, rucklidgeite, sylvanite, tellurobismuthite, tetradymite, and volynskite), and native elements (tellurium and gold). Molybdenite, muthmannite, rucklidgeite, and volynskite are reported for the first time in this deposit. We consider the Dongping gold deposit mainly formed in the Devonian, and the ore‐forming processes and the physicochemical conditions for ore formation can be reconstructed based on our newly identified ore paragenesis, that is, iron oxides → (CO2 effervescence) → sulfides → (fTe2/fS2 ratio increase) → Pb‐Bi‐tellurides → (condensation of H2Te vapor) → Au‐Ag‐tellurides → (mixing with oxidizing water) → carbonate and microporous gold → secondary minerals → secondary minerals. The logfO2 values increase from the early to late stages, while the fH2S and logfS2 values increase initially and then decrease. CO2 effervescence is the main mechanism of sulfides precipitation; this sulfidation and condensation of H2Te vapor lead to deposition of tellurides. The development of microporous gold indicates that the deposit might experience overprint after mineralization. The Dongping gold deposit has a close genetic relationship with the Shuiquangou syenite, and tellurium likely originated from Shuiquangou alkaline magmatic degassing. [ABSTRACT FROM AUTHOR]

Since the late 1960s, and as a result of the improvement of in vitro fertilization techniques, knowledge on human embryo development has considerably progressed. The purpose of this review is to provide an update on culture conditions allowing an optimal embryo development. During its development, there is a shift in nutritional requirements, in parallel with the availability of nutrients in the female genital tract and the metabolic changes that the embryo undergoes. The main metabolic transition is energy production from pyruvate uptake at cleavage-stage, followed by preferential glucose uptake from compaction. Therefore, culture media used in vitro, whether sequential or one-step, must contain all the elements necessary to get as close as possible to the micro-environment in vivo (carbohydrates, lipids, amino-acids, macromolecules). Morevover, physicochemical culture conditions (oxygen tension, temperature, pH) are variables described as having a significant impact on embryo development. Finally, other parameters such as coculture, dynamic or group embryo culture, although more controversial or difficult to implement, could allow development even closer to physiology. [ABSTRACT FROM AUTHOR]

The Late Mesozoic A-type granites are widely distributed along eastern China's Lower Yangtze River Belt (LYRB). Much attention has been paid to this region's adakitic rocks and ore deposits, whereas few studies have examined A-type granites. The largest A-type granitic pluton within the Luzong basin, the Huangmeijian (HMJ) intrusion, is composed of quartz syenite, syenogranite, syenite porphyry, and a minor quartz monzonite. Syenite porphyry in the HMJ is divided into fine-grained syenite porphyry (FSP) and coarse-grained syenite porphyry (CSP) with different grain sizes, but studies on syenite porphyry are sparse. In this study, we reported a detailed study including the in situ U–Pb age and trace-element data, whole-rock major and trace elements, apatite compositions, and Sr-Nd isotopes from the HMJ pluton, with aims to further constraints on the petrogenesis, magmatic sources, and evolution, and tectonic significance of A-type granites in the LYRB. These two syenite porphyries (FSP and CSP) in HMJ intrusion were delineated by zircon U–Pb dating with the ages of 126.4 ± 4.4 Ma and 128.9 ± 0.54 Ma respectively. They have geochemical characteristics similar to those of A-type granites, with high total-alkali (10.5–10.7 wt%), HFSEs (Zr + Nb + Ce + Y = 540.4–949.4 ppm), high Ga/Al ratios (10,000 × Ga/Al = 3.88–4.57), and high whole-rock zircon saturation temperatures (832–906 °C) and high oxygen fugacity, classified as A1 type granite. The slightly enriched Sr-Nd isotope composition (87Sr/86Sr = 0.70428–0.71275, εNd(t) = −3.26 to −5.86) of the HMJ apatite with high F and Cl contents, coupled with trace element features, indicating that syenite porphyry was likely originated from metasomatized mantle-derived magma. In addition, two groups of ancient inherited zircons were observed in the FSP, implying the contribution of the old crystalline basement and Paleozoic materials in the magma source. Moreover, significant hostile Eu, Sr, and Ba anomalies and depletion of Sr and Eu in apatite suggest the fractionation of plagioclase, K-feldspar, apatite, and Fe-Ti oxides are also reflected in their elemental variations. Comprehensive discriminant analysis shows that the HMJ syenite porphyries were derived from the metasomatized mantle-derived magma mixing with ancient crustal components in the Paleo-Pacific plate roll-back and intensive lithospheric extension setting, and followed by fractional crystallization. [Display omitted] • Huangmeijian syenite porphyries were classified as A1-type granite. • Huangmeijian A-type granite is formed by melting of slightly metasomatized lithospheric mantle. • Fractional crystallization plays critical roles in controlling the compositional variation of the Huangmeijian A-type granites. • It is a product of Paleo-Pacific plate roll-back and intensive lithospheric extension setting. [ABSTRACT FROM AUTHOR]

The eutrophic Bohai Sea receives large amount of suspended material, nutrients and contaminant from terrestrial runoff, and exchanges waters with the northern Yellow Sea through a narrow strait. This coastal region provides an ideal model system to study microbial biogeography. We performed high-throughput sequencing to investigate the distribution of bacterial taxa along spatial and environmental gradients. The results showed bacterial communities presented remarkable horizontal and vertical distribution under coastal gradients of spatial and environmental factors. Fourteen abundant taxa clustered the samples into three distinctive groups, reflecting typical habitats in shallow coastal water (seafloor depth ≤ 20 m), sunlit surface layer (at water surface with seafloor depth >20 m) and bottom water (at 2–3 m above sediment with seafloor depth >20 m). The most significant taxa of each cluster were determined by the least discriminant analysis effect size, and strongly correlated with spatial and environmental variables. Environmental factors (especially turbidity and nitrite) exhibited significant influences on bacterial beta-diversity in surface water (at 0 m sampling depth), while community similarity in bottom water (at 2–3 m above sediment) was mainly determined by depth. In both surface and bottom water, we found bacterial community similarity and the number of OTUs shared between every two sites decreased with increasing geographic distance. Bacterial dispersal was also affected by phosphate, which was possible due to the high ratios of IN/IP in this coastal sea area.

Abstract The origin of A-type granites has been the subject of great debate, especially the enigmatic synchronous A 1 - and A 2 -type granites. Cretaceous (~125 Ma) A 1 - and A 2 -type granites are common throughout the Lower Yangtze River Belt (LYRB), eastern China. However, their genesis still remains unclear. In this study, in-situ zircon Oisotopic data and chemical compositions of the Huayuangong (HYG) A-type granites in Anhui province, provide new insights into the origin and evolution of A-type granites in the LYRB, as well as the genetic link for synchronous A 1 - and A 2 -type granites. The HYG granites include syenogranite (75.9 wt%–76.6 wt% SiO 2) and quartz syenite (66.1 wt%–66.9 wt% SiO 2). Both are metaluminous and belong to ferroan series. They are characterized by high alkalis (K 2 O + Na 2 O = 8.36 wt%–8.55 wt% and 11.7 wt%–11.9 wt%), high field strength elements (Zr + Nb + Ce + Y = 909 ppm–1269 ppm and 1092 ppm–1329 ppm) and high Ga/Al ratios (10,000 ∗ Ga/Al = 4.91–4.96 and 2.64–2.68). The zircon saturation thermometer results indicate high magmatic temperatures (896–964 °C and 860–882 °C). All those geochemical features show an A-type granite affinity. They can be further classified into A 1 -and A 2 -type granites, corresponding to reduced and oxidized A-type granites, respectively. Additionally, the in-situ zircon O-Hf isotope compositions are also distinctly different, with δ18O = 4.7‰–6.0‰ and ε Hf (t) = −1.5 to −3.6 for A 1 -type granites, and δ18O = 7.0‰–7.8‰ and ε Hf (t) = −3.3 to −6.9 for A 2 -type granites. The geochemical signatures and newly discovered δ18O and ε Hf (t)values of the two A-type granite subgroups, indicate that they were derived from different source components and under disparate physicochemical conditions (e.g.,temperature, redox state and water contents). Lithospheric mantle-like isotopic data from zircons of A 1 -type granites suggest fractional crystallization of reduced, anhydrous basaltic magmas resulting in the formation of A 1 -type granites. In contrast, A 2 -type granites with relatively high δ18O and negative εHf values were generated from partial melting of the lithospheric mantle which was metasomatized by slab-derived melts/fluids. The coexisting A 1 - and A 2 -type granites were formed under the extensional setting where lithospheric thinning and asthenosphere upwelling occurred. Highlights • A-type granites in the Lower Yangtze River belt are post ridge subduction. • Coexisting A 1 - and A 2 -type granites emplaced in the same complex at Huayuangong. • Newly discovered zircon Hf-O isotopes indicate different source components. • Huayuangong was located near the transition between A 1 and A 2 -type granites. [ABSTRACT FROM AUTHOR]

Fish communities in mangrove areas have an ecological and socio-economic importance. The management in this kind of habitat is based on the data information about spatial and temporal patterns. The main goal of the study is determinate the spatial and temporal structure of the ichthic community from Tamarindo mangrove area. Six samplings trips were conducted from August 2009 to June 2010, at five mangrove stations using four different fishing gear. Also, environmental variates were recording (temperature, oxygen, salinity, pH, and water transparency). A total of 1357 individuals belonging to 59 species of 28 families were identified. Carangidae and Lutjanidae were more richness families, and the most abundant were Poecilidae, Mugilidae and Clupeidae. Poeciliopsis elongata was the most abundant species. Temporally, the diversity reached a minimum of 1.55 in December and a maximum of 1.96 in April. The richness presented a minimum of 22 species in February and a maximum of 25 in December. Spatially, the diversity reached a minimum of 1.96 in the mouth of the estuary and a maximum of 2.79 in mid estuary; the richness a minimum of 24 species inner the estuary and a maximum of 30 at mid estuary. Additionally, a temporal pattern of succession of species was determined. The fish community shows change in the similarity in their species composition from the mouth to the inner part of the estuary. At inner of the estuary the abundance was low, in contrast with the richness, diversity and equitability. Finally, nursery process for some key species for fisheries occurs in this estuary; made it fragile and susceptible to pollution and anthropogenic impacts, because their short mangrove area and shallow depth. [ABSTRACT FROM AUTHOR]

To better understand the physicochemical conditions in affecting regional distribution of phytoplankton community, one research cruise was carried out in the Bohai Sea and Yellow Sea during 3 and 23 May, 2010. The phytoplankton community, including Bacillariophyta (105 taxa), Pyrrophyta (54 taxa), Chrysophyta (1 taxon) and Chlorophyta (2 taxa), had been identified and clearly described from six ecological provinces. And, the six ecological provinces were partitioned based on the top twenty dominant species related with notable physicochemical parameters. In general, the regional distributions of phytoplankton ecological provinces were predominantly influenced by the physicochemical properties induced by the variable water masses and circulations. The predominant diatoms in most of water samples showed well adaptability in turbulent and eutrophic conditions. However, several species of dinoflagellates e.g., Protoperidinium conicum, Protoperidinium triestinum, Protoperidinium sp. and Gymnodinium lohmanni preferred warmer, saltier and nutrient-poor environment. Moreover, the dinoflagellates with high frequency in the Yellow Sea might be transported from the Yellow Sea Warm Current. The horizontal distribution of phytoplankton was depicted by diatoms and controlled by phosphate concentration, while the vertical distribution was mainly supported by light and nutrients availability in the subsurface and bottom layers, respectively. [ABSTRACT FROM AUTHOR]

A great volume of original information on the formation of the ultrabasic rocks of the Siberian Platform has been accumulated owing to the study of melt inclusions in Cr-spinels. The inclusions show the general tendencies in the behavior of the magmatic systems during the formation of the ultrabasic massifs of the Siberian Platform, tracing the main evolution trend of decreasing Mg number with SiO2 increase in the melts with subsequent transition from picrites through picrobasalts to basalts. The compositions of the melt inclusions indicate that the crystallization conditions of the rocks of the concentrically zoned massifs (Konder, Inagli, Chad) sharply differ from those of the Guli massif. Numerical modeling using the PETROLOG and PLUTON softwares and data on the composition of inclusions in Cr-spinels yielded maximum crystallization temperatures of the olivines from the dunites of the Konder (1545-1430°C), Inagli (1530-1430°C), Chad (1460-1420°C), and Guli (1520-1420°C) massifs, and those of Cr-spinels from the Konder (1420-1380°C), Inagli (up to 1430°C), Chad (1430-1330°C), and Guli (1410-1370°C) massifs. Modeling of the Guli massif with the PLUTON software using the compositions of the melt inclusions revealed the possible formation of the alkaline rocks at the final reverse stage of the evolution of the picritic magmas (with decrease of SiO2 and alkali accumulation) after termination of olivine crystallization with temperature decrease from 1240-1230°C to 1200-1090°C. Modeling with the PLUTON software showed that the dunites of the Guli massif coexisted with Fe-rich (with moderate TiO2 contents) melts, the crystallization of which led (beginning from 1210°C) to the formation of pyroxenes between cumulate olivine. Further temperature decrease (from 1125°C) with decreasing FeO and TiO2 contents provided the formation of clinopyroxenes of pyroxenites. For the Konder massif, modeling with the PLUTON software indicates the possible formation of kosvites from picrobasaltic magmas beginning from 1350°C and the formation of clinopyroxenites and olivine-diopside rocks from olivine basaltic melts from 1250°C. [ABSTRACT FROM AUTHOR]

The fragility of geographically isolated islands stresses the necessity of evaluating the current situation, identifying temporal trends and suggesting appropriate conservation measures. To support this, we assessed the freshwater quality of three stream basins on San Cristóbal (Galapagos) for two consecutive years. Abiotic conditions generally complied with existing guidelines, except for the pH in the Cerro Gato basin (0.12 mg P L−1). Macroinvertebrate communities were characterized by low family richness (3−11) and were dominated by Atyidae or Chironomidae, thereby causing low diversity (0.33−1.65). Spatial analysis via principal component analysis (PCA) illustrated that abiotic differences between stream basins were mostly related to turbidity, pH, dissolved oxygen (DO), and conductivity. Biotic differences were less clear due to masking by anthropogenic disturbances and dispersal limitations, yet indicated a negative effect of reduced pH and DO on Atyidae presence. In 2017, significantly narrower ranges were found for turbidity, temperature, pH, and diversity (p < 0.01), suggesting a decrease in habitat variability and a need for conservation measures, including mitigating measures related to dam construction for water extraction. As such, further follow-up is highly recommended for the sustainable development and environmental protection of this unique archipelago.

The Mianeh iron skarn deposit lies in the Arasbaran region within the Qaradagh metallogenic district, NW Iran. This high-grade massive magnetite skarn originated by the interaction of Upper Cretaceous limestone with metasomatic ore-bearing fluids associated with hypabyssal Oligo-Miocene quartz diorite. Mineral chemistry of the primary clinopyroxenes demonstrates the sub-alkaline, volcanic arc setting of magmatism. Two general stages of skarnification are recognized: (1) silicate skarn ( stage I) is composed essentially of grossular and low-Fe diopside formed before the main mineralization and (2) magnetite-garnet skarn ( stage II) composed of strongly anisotropic coarse-grained garnets with a narrow compositional zoning radially formed by addictive infiltrating of silica and iron-rich metasomatic fluids which overprint and/or crosscut the early stage silicate skarn. Anhydrous prograde calc-silicate assemblages were replaced by a series of hydrous calc-silicates (epidote, tremolite-actinolite) and/or quartz, calcite, magnetite, hematite, and pyrite. Magnetite (±hematite) is the dominant hypogene ore mineral that initially precipitated coincident with the late prograde to the early retrograde metasomatic stages. Mineralogical studies suggest that silicate skarn formation commenced at temperatures about 560 °C, X(CO) ≤ 0.15, αSiO∼−1.0, and fluid pressure 1.0 kbar. The magnetite-garnet skarn formed from HO-rich fluids [X(CO) < 0.1] at a temperature of 525 to 450 °C and maximum log ƒO between −20.2 and −23. During the late stages of prograde skarn development, the stability field of andradite shifted to low ƒO and ƒS conditions resulting in main iron ore deposition (as magnetite). The andradite replacement temperature and presence of pyrite (instead of pyrrhotite) suggest that logƒS remained constant at about −6 to −7 during cooling of the system. [ABSTRACT FROM AUTHOR]

In this study, to gain an improved understanding of the fate and fractionation of particle-bound pollutants, we evaluated the physicochemical conditions and the properties of particles in rainwater, urban runoff, and rivers of Yixing, a city with a large drainage density in the Taihu Lake Basin, China. Road runoff and river samples were collected during the wet and dry seasons in 2015 and 2016. There were significant differences between the physicochemical conditions (pH, oxidation-reduction potential (ORP), and electroconductivity (EC)) of rainwater, runoff, and rivers. The lowest pH and highest ORP values of rainwater provide the optimal conditions for leaching of particle-bound pollutants such as heavy metals. The differences in the physicochemical conditions of the runoff and rivers may contribute to the redistribution of pollutants between particulate and dissolved phases after runoff is discharged into waterways. Runoff and river particles were mainly composed of silt and clay (<63 μm, 88.3%–90.7%), and runoff particles contained a higher proportion of nano-scale particles (<1 μm) but a lower proportion of submicron-scale particles (1–16 μm) than rivers. The ratio of turbidity to TSS increased with the proportion of fine particles and was associated with the accumulation of pollutants and settling ability of particles, which shows that it can be used as an index when monitoring runoff pollution. [ABSTRACT FROM AUTHOR]

[Display omitted] • The independent selenides coexisting with tellurides and sulfides were discovered for the first time in the Zhaishang gold deposit. • The ore-forming materials leached from the underlying Paleozoic strata, and were affected by Indosinian magmatism. • The mineral paragenetic association shows that the redox conditions have changed from reduction to oxidation during the fluid evolution process. • The sulfur, tellurium and selenium fugacity of hydrothermal fluid of the main metallogenic stage is estimated in this paper. The Zhaishang gold deposit is characterized by Au–Sb–W paragenetic association, hosted in the Middle Devonian strata and Lower Permian strata of the Western Qinling Orogen, Central China; also found in in the mining area is a small carbonatized diorite porphyrite. Besides common sulfides, such as pyrite, arsenopyrite and chalcopyrite, some specific telluride and selenide minerals were found, and especially the first discovery of independent selenides. The assemblage pyrrhotite–arsenianpyrite–arsenopyrite suggests a relatively reducing environment for mineralization during stage II. However, the occurrence of selenides (clausthalite, tiemannite) and sulfates (barite and gypsum) represents a change of redox conditions from reduction to oxidation in stage III. On this basis, combined with the study of fluid inclusions and thermodynamic data, we evaluated the physicochemical conditions of the main metallogenic stages. the sulfur fugacity (log f S 2) did not change significantly from stage II to stage III, the selenium fugacity (log f Se 2) values were constrained to have been ≤ -13.7 in stage II, ranged from −14.8 to −9.8 in stage III, and the tellurium fugacity (log f Te 2) ranged from −14.0 to −11.2 in stage III. Moreover, the He–Ar–Pb isotopic values of sulfides suggest that ore-forming materials were dominantly of stratigraphic source but with important additions of magmatically derived hydrothermal fluid during Indosinian period. Water-rock reaction and ore-forming fluid mixed with magmatically-derived hydrothermal fluid were likely the dominant mechanisms of precipitation. Meanwhile, boiling likely played a certain role in the deposition of selenides and tellurides. [ABSTRACT FROM AUTHOR]

The Cu-Sb-Pb polymetallic vein deposit is hosted by metavolcanics rocks of the Gawuch Formation at the Kaldom Gol area of the northwest Kohistan arc terrain in northern Pakistan. The mineralization is closely associated with the dioritic to granodioritic rocks of the Lowari pluton, which was intruded into the Gawuch metavolcanics. Details of ore characterization and processes of ore genesis of this evidently hydrothermal mineralization are not well documented. Integrating petrographic, mineral-chemical and isotopic investigations, this study aims to comprehend the source of hydrothermal fluids, geochemical evolution, mineral inclusions and physicochemical conditions of the Cu-Sb-Pb polymetallic vein deposit in Gawuch metavolcanics in the Kohistan arc terrain in northern Pakistan. The mineralization is distinguished into three types of ore-gangue associations: Type Ia, Type Ib, and Type II. The textural study revealed two pyrite generations: (i) Py1 displaying euhedral to subhedral habits and containing scarce inclusions, and (ii) Py2 occurring as anhedral grains hosting abundant inclusions. Type Ia is characterized by Py1 associated with abundant quartz (Qz) showing comb texture, sericite (Ser), and minor chlorite (Chl). Type Ib comprises Qz + Ser + Chl and Py2, chalcopyrite (Ccp), and magnetite (Mag). Type II is represented by mosaic quartz, rhombic adularia, and bladed calcite, and the ore minerals fahlore and galena. Alteration zones composed of Qz-Ser ± Chl and Qz-Ser-Chl, surround Type I (a, b) and Type II veins, respectively. Fahlore and galena mostly replace pyrite of Type Ia and chalcopyrite of Type Ib. In addition, malachite, azurite, hematite and covellite occur as secondary (supergene) minerals. The Co/Ni ratios (>1) of Kaldom Gol pyrites suggest that the ore-forming fluids were hydrothermal in origin and Py1 and Py2 solidified at 221–304 °C and 225–261 °C, respectively. The LA-ICP-MS time-resolved depth profiles confirm the existence of sphalerite, and chalcopyrite inclusions in pyrite (Py1 and Py2) and millerite , bravoite , vaesite , Au-tellurides, native Au and galena inclusions in chalcopyrite and fahlore. Sulfur isotope compositions of pyrites (δ34S = Py1, −0.58 to +2 ‰; δ34S = Py2, −0.24 to +2.04 ‰) indicate that the ore-forming fluids were derived from magmatic source (s). The mineral assemblage, hydrothermal alterations, textures, temperature and δ34S of pyrites suggest that the Cu-Sb-Pb polymetallic mineralization at Kaldom Gol represents an intermediate-sulfidation type of epithermal deposit. [Display omitted] [ABSTRACT FROM AUTHOR]

The opportunistic fungal pathogens belonging to the Candida haemulonii complex and the phylogenetically related species Candida auris are well-known for causing infections that are difficult to treat due to their multidrug-resistance profiles. Candida auris is even more worrisome due to its ability to cause outbreaks in healthcare settings. These emerging yeasts produce a wide range of virulence factors that facilitate the development of the infectious process. In recent years, the aggregative phenotype has been receiving attention, as it is mainly associated with defects in cellular division and its possible involvement in helping the fungus to escape from the host immune responses. In the present study, we initially investigated the aggregation ability of 18 clinical isolates belonging to the C. haemulonii species complex ( C. haemulonii sensu stricto , C. duobushaemulonii , and C. haemulonii var. vulnera ) and C. auris . Subsequently, we evaluated the effects of physicochemical factors on fungal aggregation competence. The results demonstrated that cell-to-cell aggregation was a typically time-dependent event, in which almost all studied fungal isolates of both the C. haemulonii species complex and C. auris exhibited high aggregation after 2 h of incubation at 37 °C. Interestingly, the fungal cells forming the aggregates remained viable. The aggregation of all isolates was not impacted by pH, temperature, β-mercaptoethanol (a protein-denaturing agent), or EDTA (a chelator agent). Conversely, proteinase K, trypsin, and sodium dodecyl sulfate (SDS) significantly diminished the fungal aggregation. Collectively, our results demonstrated that the aggregation ability of these opportunistic yeast pathogens is time-dependent, and surface proteins and hydrophobic interactions seem to mediate cell aggregation since the presence of proteases and anionic detergents affected the aggregation capability. However, further studies are necessary to better elucidate the molecular aspects of this intriguing phenomenon.

The protein osteopontin (OPN) plays an important role in preventing the formation of calcium oxalate monohydrate (COM) kidney stones. To gain insight into these mechanisms, crystallization was induced by addition of human kidney OPN to artificial urine (ionic strength comparable to urine; without citrate), and the OPN-COM interaction studied using a combination of scanning electron (SEM) and confocal microscopy. By SEM, we found that increasing OPN concentrations formed large monoclinic penetration twins (no protein added) and, at higher concentrations (1-, 2 μg/ml OPN), super and hyper twins with crystal habits not found in previous studies. For instance, the hyper twins indicate well-facetted gearwheel-like habits with “teeth” developed in all crystallographic < h 0 l > directions. At OPN concentrations ≥2 μg/ml, a switching to small dumbbell-shaped COM habits with fine-textured surfaces occurred. Confocal microscopy of these dumbbells indicates protein incorporation in almost the entire crystal structure (in contrast to facetted COM), proposing a threshold concentration of ∼2 μg/ml OPN for the facetted to the non-facetted habit transformation. Both the gearwheel-like and the dumbbell-shaped habit are again found side-by-side (presumably triggered by OPN concentration gradients within the sample) in in-vitro formed conglomerates, which resemble cross-sections of papillary kidney stones. The abrupt transformation from facetted to non-facetted habits and the unique compliance of the two in-vitro formed habits with the two main morphologies found in papillary kidney stones propose that OPN is a main effector in direct stone-forming processes. Moreover, stone structures which exhibit these two morphologies side-by-side might serve as a novel indicator for OPN concentrations surrounding those structures. [ABSTRACT FROM AUTHOR]

The Sanjiang Tethyan domain in SE Asia is one of the most important mineral belts in China. Cu, Pb–Zn, Ag, Au and Sn are the most important resources in this domain, while the tungsten mineralization is poorly reported. In this study, we report on mineralogy in recent discovered Damajianshan (DMJS) tungsten (–Cu–As–Mo–Bi) polymetallic deposit in the southern part of Sanjiang Tethyan domain related to Triassic quartz porphyry. Studies have shown that besides common ore minerals, such as native bismuth, bismuthinite, ikunolite, some specific minerals of Pb–Bi- and Pb–Sb-sulphosalts (e.g. izoklakeite, bournonite, cosalite, and boulangerite) have also been found. Based on paragenetic mineral assemblages, fluid inclusions, and thermodynamic studies, the physicochemical conditions were evaluated for the entire metallogenic process. The sulfur fugacity (logf S2 ) ranges from − 9.7 to − 37 with ore-forming temperatures between 190 °C and 330 °C, and the oxygen fugacity (logf O2 ) ranges from − 37.5 to − 38.5 when the temperature is 250 °C. The sulfur fugacity and oxygen fugacity show strong fluctuations with broadly negative correlation, indicating that these variations in physicochemical conditions should be responsible for mineral assemblages, and are one of the most significant factors leading to the formation of the DMJS deposit. Our mineralogical studies provide new information for tungsten mineralization and further exploration of tungsten resources in the Sanjiang Tethyan mineralization domain. [ABSTRACT FROM AUTHOR]

Pseudomonas fluorescens group species are indigenous bacteria in many different environments. The physicochemical conditions related to their selection to different surface and subsurface environments are poorly understood. We isolated 35 P. fluorescens group strains under the pesticide stress from mesocosms of surface soils and groundwater-monitoring pipe deposit slurries, and from a few of their initially sterilized counterparts, which were colonized during 599-625 days of laboratory incubation. In addition, strains were isolated from mesocosms of drilling sediment slurries. Based on the 16S rDNA analysis, strains belonged to five species. The statistical analysis of relationships between the isolates and physicochemical conditions in their isolation mesocosms revealed the typical habitats of five species. Pseudomonas IC038 and Pseudomonas LAB-23-like strains were common in mesocosms of deposit/sediment slurries low in growth substrates. Pseudomonas marginalis-like isolates preferred surface soil mesocosms rich in nutrients. Pseudomonas veronii and Pseudomonas mandelii-like strains grew in mesocosms of surface soils and subsurface deposit/sediment slurries, which indicated that they either had a versatile metabolism to adapt to different environments, or differed in substrate specificities. The initially sterilized mesocosms were mainly colonized with the same species as their non-sterilized counterparts, while all P. fluorescens group species tolerated atrazine and/or terbutryn. Our results on habitats were in agreement with the isolation sources of strains with identical 16S rDNA sequences in databases. The observed differences in the distribution patterns of the P. fluorescens group species indicate that species selection should be carefully done for man-made ecosystem applications, such as stable bioremediation. [ABSTRACT FROM AUTHOR]

In coastal lagoons with occasional connection to oceans, variations in physicochemical conditions and biological responses can be pronounced. To examine the influence of variable rainfall and tidal flushing, we measured, over a 4-year period, salinity, temperature and dissolved oxygen, and fish abundances, in Devereux Slough, a coastal lagoon occasionally connected to the Pacific Ocean along the California coast. We test the hypotheses that salinity is the primary influence on fish composition, and that fish density is affected by freshwater discharge and by berm breaches. During our sampled years, annual rainfall varied from 188 to 971 mm, and the sand berm separating the Slough from the ocean breached in each year except 2007, a drought period. Average yearly salinity ranged from 7.7 to 37.1 ppt. Hypoxic conditions in the near-bottom water were common each year. The best predictor of the fish composition was salinity, and an indirect correlation with fresh water discharge was responsible for much of the temporal variation in the fish assemblage. The interaction between salinity, state of the estuary mouth (open vs. closed), and precipitation significantly predicted densities of Fundulus parvipinnis (Girard 1984). [ABSTRACT FROM AUTHOR]

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Abstract: Study of fluid inclusions in minerals from sulfide ores sampled in the Ashadze and Logatchev hydrothermal fields during the Serpentine cruise of the R/V Pourquoi Pas? in 2007 gave an insight into the physicochemical conditions of ore-forming systems of “black smokers” associated with mantle ultrabasites in the Central Atlantic region. It was established that the studied hydrothermal systems differ in mineral formation temperatures, fluid salinity, and hydrothermal processes running within basaltic complexes in both low-spreading (Mid-Atlantic Ridge) and high-spreading (East Pacific Rise) mid-ocean ridges. It was shown for the Ashadze and Logatchev hydrothermal fields that the temperatures and salinity of inclusion solutions in the minerals vary over a wider range of values than those of fluids flowing out from the ridge vents onto the ocean floor. Study of fluid inclusions showed that the Ashadze and Logatchev sulfide structures resulted from the action of both high-temperature (up to 355 °C) and low-temperature (no lower than 170 °C) solutions. The salinity of fluid in the inclusions (mainly 8 wt.%) is more than twice as high as the salinity of seawater. The data obtained substantiate the phase separation of fluid in the deepest-water submarine hydrothermal Ashadze system and give an idea of the chemical composition and temperature of fluids forming sulfide deposits in the Ashadze and Logatchev hydrothermal fields in the Central Atlantic region. [Copyright &y& Elsevier]

Abstract: The shrink-swell behavior of active clays in response to changes in physicochemical conditions creates great challenges for construction of geotechnical barriers for hazardous waste isolation, and is of significant importance for management of agricultural and natural resources. Initiation and evolution of desiccation cracks in active clays are strongly dependent on physicochemical initial and boundary conditions. To investigate effects of bentonite content (20, 40, 60%), pore fluid chemistry (0.05 and 0.5M NaCl) and drying rates (40 and 60°C) on cracking behavior, well-controlled dehydration experiments were conducted and X-ray Computed Tomography (CT) was applied to visualize and quantify geometrical features of evolving crack networks. A stochastic model based on the Fokker-Plank equation was adopted to describe the evolution of crack aperture distributions (CAD) and to assess the impact of physicochemical factors on cracking behavior. Analyses of crack porosity and crack specific surface area showed that both clay content and temperature had larger impact on cracking than pore fluid concentration. More cracks formed at high bentonite contents (40 and 60%) and at high drying rate (60°C). The drift, diffusion and source terms derived from stochastic analysis indicated that evaporative demand had greater influence on the dynamics of the CAD than solution chemistry. [Copyright &y& Elsevier]

Worldwide, there have been few comparative studies on rotifer communities in subtropical lakes. We studied changes in rotifer community structure over 1 year and its relationship to several physicochemical variables in five subtropical shallow lakes in East China, covering a nutrient gradient from mesotrophy to moderate eutrophy. In these lakes, the genera Brachionus, Lecane, and Trichocerca dominated the rotifer species composition, and Polyarthra dolichoptera, Keratella cochlearis, Filinia longiseta, T. pusilla, and Anuraeopsis fissa were the dominant species. With increased nutrient loading, total rotifer abundance and species dominance increased, indicating that rotifer abundance might be a more sensitive indicator of trophic state than species composition. Comparative analyses of the six rotifer community indices calculated in this study and redundancy analysis (RDA) revealed that the two slightly eutrophic lakes and the other two moderately eutrophic lakes exhibited a high degree similarity in community structure. This suggests that the trophic state of a lake determines the rotifer community structure. In contrast, in the two moderately eutrophic lakes, the mass ratios of TN:TP and the contents of TP suggested N-limitation and cyanobacteria dominance in phytoplankton communities might be possible. In these lakes TN played a more important role in shaping the rotifer community according to stepwise multiple regression and RDA. RDA analysis also suggested that rotifer species distribution was strongly associated with trophic state and water temperature, with water temperature being the most important factor in determining seasonality. [ABSTRACT FROM AUTHOR]

Abstract: Complex petrological, geochemical, and isotope studies of igneous rocks sampled from the core of parametric Maizasskaya BH-1 showed a predominance of dolerite sills, which formed earlier (~263 ± 4 Ma) than most of basalts in the basement of the West Siberian sedimentary basin and in the Siberian Platform traps (248–251 Ma). Their formation took place during the crystallization of basaltic melt in intrusive chambers existing between layers of Silurian sedimentary rocks. The petrochemical, geochemical, mineralogical, and thermobarogeochemical data show that the sills resulted from the activity of complex magmatic systems different from typical oceanic and plateau-basalt melts and related, most likely, to the formation of rift structures under the influence of mantle plume. Study of melt inclusions provided data on the conditions of generation of primary melts from mantle substratum (≤1570 ºC, depths to 105–120 km) and crystallization parameters of dolerites—1130–1155 ºC, 1.5–2 kbar. The results obtained show that the studied basalt complexes in West Siberia are genetically related to the mantle plume activity, which led to the breakup of ancient crust and rifting. Formation of oceanic crust took place in the largest rifts; the ascending magma penetrated into the enclosing ancient strata to form sills. [Copyright &y& Elsevier]