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The electrochemical interaction between galena and monoclinic pyrrhotite was investigated to examine its impact on the physical and chemical properties of the mineral micro-surface. This investigation employed techniques such as electrochemistry, metal ion stripping, X-ray photoelectron spectroscopy, and quantum chemistry. The electrochemical test results demonstrate that the galena surface in the electro-couple system exhibits a lower electrostatic potential and higher electrochemical activity compared to the monoclinic pyrrhotite surface, rendering it more susceptible to oxidation dissolution. Monoclinic pyrrhotite significantly amplifies the corrosion rate of the galena surface. Mulliken charge population calculations indicate that electrons are consistently transferred from galena to monoclinic pyrrhotite, with the number of electron transfers on the mineral surface increasing as the interaction distance decreases. The analysis of state density revealed a shift in the surface state density of galena towards lower energy levels, resulting in decreased reactivity and increased difficulty for the reagent to adsorb onto the mineral surface. Conversely, monoclinic pyrrhotite exhibited an opposite trend. The X-ray photoelectron spectroscopy (XPS) test results indicate that galvanic interaction leads to the formation of hydrophilic substances, PbSxOy and Pb(OH)2, on the surface of galena. Additionally, the surface of monoclinic pyrrhotite not only adsorbs Pb2+ but also undergoes S0 formation, thereby augmenting its hydrophobic nature.

Nostolachma jenkinsii (Hook.f.) Deb & J.Lahiri, a member of the Rubiaceae family, is an endangered wild plant species with potential economic value. In this research, the complete chloroplast genome of N. jenkinsii was sequenced to gain insight into its genome feature and better understand the phylogenetic relationships among the Rubiaceae species. The chloroplast genome, with a total length of 155,036 bp, comprises two inverted repeats (IR) regions spanning 25,692 bp each, a large single-copy (LSC) region measuring 85,437 bp, and a short single-copy (SSC) region measuring 18,215 bp. There is an overall 37% GC content in the chloroplast genome. By annotation analysis,. 54 tRNA genes, 10 rRNA genes, and 107 protein-coding genes were all annotated in N. jenkinsii. Furthermore, we applied phylogenetic analysis that revealed a close relationship between N. jenkinsii, D. fruticosa and D. dubia, placing them together within the Rubiaceae family.

The floatability of fluorite and calcite exhibit similar properties, rendering their flotation separation challenging. Macromolecular polysaccharide reagents containing the polyhydroxyl group have shown broad promising application. The selectivity of polysaccharide is relatively low. In this study, the introduction of Fe3+ was employed to enhance the selective adsorption capacity of Pullulan polysaccharide towards fluorite and calcite minerals, thereby achieving effective flotation separation. Furthermore, the mechanism underlying intramolecular interactions was elucidated. The DFT calculation and XPS analysis revealed that the adsorption of Fe3+ on the calcite surface was more favorable, leading to the formation of a Ca-O-Fe structure. The MD simulation, XPS analysis, and Zeta potential analysis revealed that the Fe-OH groups on the surface of calcite reacted with the -OH groups in Pullulan and formed bonds, resulting in the formation of a Calcite-Fe-Pullulan structure. This facilitated the attachment of a significant number of Pullulan molecules to the calcite surface. The formation of a hydrophilic layer on the outer surface of calcite by Pullulan, in contrast to the absence of such layer on fluorite’s surface, results in an increased disparity in surface floatability between these two minerals, thereby enhancing the efficiency of flotation separation.

The mechanism of electrochemical interaction between chalcopyrite and hexagonal pyrrhotite was analyzed via electrochemical interaction, copper ion concentration testing, and X-ray photoelectron spectroscopy (XPS) characterization. Besides, the effect of electrochemical interaction between the two minerals on the flotation separation was investigated using the mineral flotation tests, adsorption capacity tests, and a microcalorimetric test. Our research results showed that chalcopyrite had higher electrochemical activity than hexagonal pyrrhotite, and when the former acted as an anode during the electrochemical interaction of the two, the corrosion current density was three times higher than that when it acted alone, and the surface oxidation corrosion was intensified. At the same time, the interaction between the two minerals was accompanied by a large number of copper ions dissolved and adsorbed on the surface of the hexagonal pyrrhotite, so that adsorption of butyl xanthate intensified, adsorption increased, and flotation recovery increased by 5%–20%. However, owing to the increase in metal defects and the generation of hydrophilic sulfate, the surface of chalcopyrite hindered the adsorption of butyl xanthate on its surface, and the flotation recovery decreased by nearly 10% compared with that before the occurrence of the electrochemical interaction. This action also significantly weakened the inhibition effect of lime on hexagonal pyrrhotite and increased the difficulty of the flotation separation of the two minerals. The research results of this study provide theoretical guidance for the flotation separation of copper–sulfur ores containing pyrrhotite.

Due to the optimum dissolution of the hydroxyl ion, serpentine is positively charged and tends to cover the sulfide mineral surface as a slime coating through electrostatic attraction, which intensively worsens sulfide flotation. To handle this problem, the sodium of polyaspartic acid (PASP) was employed as the selective depressant for the flotation of pyrite from serpentine in this work. Micro-flotation results showed that the fine serpentine of −10 µm could intensively hinder pyrite flotation, with a maximum decrease of about 75.8% in pyrite recovery at pH 9. However, at this pH, pyrite recovery remarkably increased from 20.17% to 92.68% when 15 mg/L PASP was introduced. Zeta potential results depicted that the addition of PASP overcompensated the positive charge on the serpentine surface and rendered it negative, while it had little impact on that of pyrite. Hence, the hetero-coagulation between serpentine and pyrite was broken due to the electrostatic repulsion, which was further confirmed by turbidity results. After that, the adsorption of PAX on the pyrite surface was restored, and the selective flotation of pyrite from serpentine was obtained. XPS analyses revealed that the chelation interaction between the carboxylate groups in PASP and the magnesium cations that remained on the serpentine surface were the main driving forces for the adsorption of PASP on the serpentine surface.

At present, the research on flotation separation of cassiterite and gangue minerals is mainly focused on the development of new collectors or depressants, while the research on combined depressants is rare. In this study, the flotation separation of cassiterite and the typical gangue mineral, calcite, was investigated using the metal-inorganic complex depressant AlSS, composed of aluminum sulfate (Al2(SO4)3) and water glass (Na2SiO3·4H2O). The flotation results indicated that, with the assistance of Al3+, the inhibition effect of SS (water glass) on calcite is significantly enhanced, while the inhibition effect on cassiterite is almost unchanged. The zeta potential and adsorption measurements proved that the formation of the negatively charged colloidal particles composed of Alm(OH)n3m−n and SiOm(OH)n4−2m−n tended to adsorb on the positively charged calcite surface, inhibiting the adsorption of sodium oleate (NaOL), while the adsorption of the colloidal particles on the negatively charged cassiterite surface is relatively less. The contact angle measurements indicate that the contact angle of cassiterite in the NaOL + AlSS solution is obviously larger than that of calcite, which indicates that cassiterite has better floatability in this system. The X-ray photoelectron spectroscopy (XPS) analysis confirms the Al and Si species are adsorbed on the surface of calcite, but not on the cassiterite. In addition, the adsorption of AlSS on cassiterite and calcite changes the chemical environment on the calcite surface, indicating that the adsorption of AlSS on the mineral surface is more inclined to be through a chemical reaction.

Objective To investigate the relationship between pretreatment plasma D-dimer levels and survival in Chinese patients with small cell lung cancer (SCLC). Methods This retrospective study enrolled 82 patients with SCLC treated at Beijing Chaoyang Hospital, Capital Medical University, from January 2012 to January 2015. All patients were followed up. Associations between pretreatment plasma D-dimer levels measured by immunoturbidimetric assay and clinical outcomes were analyzed by Kaplan–Meier and multivariate analyses, using a cut-off level of 0.55 mg/L fibrinogen equivalent units (FEU). Results Median progression-free survival (PFS) and overall survival (OS) were significantly higher in patients with low D-dimer levels (≤0.55 mg/L FEU; 8.0 and 17.0 months, respectively) compared with patients with high levels (>0.55 mg/L FEU; 5.0 and 9.0 months, respectively). Plasma D-dimer levels, Karnofsky performance status, N stage, TNM stage, treatment, and neuron-specific enolase (NSE) levels were significantly associated with PFS, while D-dimer levels, N stage, TNM stage, and treatment were significantly associated with OS. Multivariate analysis revealed that TNM stage, treatment, and NSE levels were independently associated with PFS, while D-dimer levels and treatment were independently associated with OS. Conclusions Pretreatment plasma D-dimer levels were independently associated with OS in patients with SCLC.

Cinnamomum glanduliferum (Wall) Meissn is a commercially important timber tree and wild spice plants of the genus Cinnamomum Trew in the family Lauraceae. To determine its phylogenetic location with respect to the other Cinnamomum species, the complete plastid genome of C. glanduliferum was sequenced. The whole plastome is 152,715 bp in length, consisting of a pair of inverted repeat (IR) regions of 20,114 bp, one large single copy (LSC) region of 93,617 bp, and one small single copy (SSC) region of 18,870 bp. The overall GC content of the whole plastome is 39.1%. Further, maximum likelihood phylogenetic analyse was conducted using 13 complete plastomes of the Lauraceae, which support close relationship between C. glanduliferum and C. bodinieri.

Alseodaphne petiolaris Hook.f. is a valuable timber tree of the genus Alseodaphne Nees in the family Lauraceae. To better determine its phylogenetic location with respect to the other Alseodaphne species, the complete plastid genome of A. petiolaris was sequenced. The whole plastome is 152,986 bp in length, consisting of a pair of inverted repeat (IR) regions of 20,108 bp, one large single copy (LSC) region of 93,863 bp, and one small single copy (SSC) region of 18,907 bp. The overall GC content of the whole plastome is 39.1%. Further, maximum-likelihood phylogenetic analyse was conducted using 15 complete plastomes of the Lauraceae, which support the close relationship between A. petiolaris and the species of Machilus and Phoebe.

Multiple myeloma (MM) is an incurable malignancy of mature B-lymphoid cells, and its pathogenesis is only partially understood. Previous studies have demonstrated that a number of Non-Hodgkin Lymphoma (NHL) associated genes also show susceptibility to MM, suggesting malignancies originating from B cells may share similar genetic susceptibility. Several recent large-scale genome-wide association studies (GWAS) have identified HLA-I, HLA-II, CXCR5, ETS1, LPP and NCOA1 genes as genetic risk factors associated with NHL, and this study aimed to investigate whether these genes polymorphisms confer susceptibility with MM in the Chinese Han population. In 827 MM cases and 709 healthy controls of Chinese Han, seven single nucleotide polymorphisms (SNPs) in the HLA-I region (rs6457327), the HLA-II region (rs2647012 and rs7755224), the CXCR5 gene (rs4938573), the ETS1 gene (rs4937362), the LPP gene (rs6444305), and the NCOA1 region (rs79480871) were genotyped using the Sequenom platform. Our study indicated that genotype and allele frequencies of rs79480871 showed strong associations with MM patients (pa = 3.5×10-4 and pa = 1.5×10-4), and the rs6457327 genotype was more readily associated with MM patients than with controls (pa = 4.9×10-3). This study was the first to reveal the correlation between NCOA1 gene polymorphisms and MM patients, indicating that NCOA1 might be a novel susceptibility gene for MM patients in the Chinese Han population.

A new species, Uncifera motuoensis (Orchidaceae: Epidedroideae: Aeridinae) from Xizang Autonomous Region, China is described and illustrated with detailed photos and scientific illustration. Detailed morphological comparisons indicate that U. motouensis is similar to U. obtusifolia, but differs in having entire mid-lobe of lip, narrower leaf blade and wider pollinarium stipe. For the identification, a key to the known seven species of Uncifera is presented. [ABSTRACT FROM AUTHOR]

The present study employed density functional theory (DFT) to analyze the adsorption configuration and mechanism of Fe(OH)2 + on the kaolinite (001) surface. The findings demonstrated that Fe(OH)2(H2O)4 + is the main type in which hydrated Fe(OH)2 + can be found in aqueous solution. On the surface of kaolinite, Fe(OH)2(H2O)4 + will be adsorbed. There are two forms of adsorption: outersphere and inner-sphere coordination (monodentate/bidentate) adsorption. Fe(OH)2(H2O)4 + has a moderate propensity to adsorb on the alumina octahedral sheet of kaolinite when the outer-sphere coordination adsorption takes place. In cases of inner-sphere coordination adsorption, Fe exhibits a tendency to form monodentate adsorption compounds in conjunction with Ou atoms. Additionally, it prefers to create bidentate adsorption compounds through coordination with both Ot and Ou atoms. The adsorption mechanism analysis results show that the ionic property of Fe atom decreases after outer-sphere coordination adsorption. After inner-sphere coordination adsorption, some electrons of Fe atom are transferred to the surface O atom. The presence of electrons between the Fe and O atoms enhances the formation of bonds, hence enhancing the covalent nature of the Fe-O bond. Theoretical FT-IR (Fourier transform infrared spectroscopy) calculations show that the formation of Fe-O chemical bonds. Because of the lower adsorption energy and more chemical bonds, hydrate Fe(OH)2 + is more likely to be bidentate adsorbed on the kaolinite surface. [ABSTRACT FROM AUTHOR]