[Characteristics of Pollution and Microbial Community Structure in the Antimony Mining Area of Longnan, Gansu Province].

Antimony （Sb） is a major pollutant that poses a serious threat to the environment in the mining and processing of nonferrous metals, coexisting with sulfide and oxide of arsenic （As）. Microorganisms play an important role in the migration, transformation, and repair of metals in soil. The ecological effects of bioavailable Sb and As on the microbial community in antimony mining areas（mining and smelting areas）are still poorly understood. The Wenzel method and high-throughput 16S rDNA amplicon were used to characterize soil pollution characteristics in different functional areas, and the relationship between the bacterial community and bioavailable concentrations have been investigated comprehensively. The results showed that： Chemical speciation of Sb and As were amorphous, and poorly crystalline hydrous oxides of Fe and Al （F3） > well-crystallized hydrous oxides of Fe and Al （F4） > residual phases （F5） > specifically adsorbed （F2） > non-specifically adsorbed （F1）. According to the estimation of the potential ecological risk index （RI） and geo-accumulation index （Igeo）, the Sb pollution degree was： smelting area > mining area > contrast area, in which the smelting area showed serious pollution, and the mining area showed moderate to severe pollution. The As pollution degree was： mining area > smelting area > contrast area, in which the mining area and smelting area showed moderate to severe pollution. High-throughput 16S rDNA amplicon showed that Proteobacteria was the most abundant phylum in mining and smelting areas； Kaistobacter, Pseudomonas, Sphingomonas, and Lysobacter were the most abundant microbial genera； Geobacter and Luteolibacter had a high LDA score in mining areas； and Thiobacillus had a high LDA score in antimony-contaminated areas. Spearman correlation analysis, variation partitioning analysis （VPA）, and random forest （RF） analysis showed that Sb, As, bioavailable antimony [Sb （Bio）], and bioavailable arsenic [As （Bio）]were the main factors affecting the microbial community structure in different functional areas of antimony ore. Redundancy analysis （RDA） indicated that Sb and its bioavailable concentrations showed uniformly negative associations with the relative abundance of bacteria Nitrospirae and showed a significant positive correlation with Thiobacillus （P<0.05）. The in-depth research on the ecological effects of bioavailable Sb and As on the bacterial community provides references and new perspectives for environmental monitoring and management.

Neoadjuvant sintilimab plus chemotherapy in EGFR-mutant NSCLC: Phase 2 trial interim results (NEOTIDE/CTONG2104).

The clinical efficacy of neoadjuvant immunotherapy plus chemotherapy remains elusive in localized epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). Here, we report interim results of a Simon's two-stage design, phase 2 trial using neoadjuvant sintilimab with carboplatin and nab-paclitaxel in resectable EGFR-mutant NSCLC. All 18 patients undergo radical surgery, with one patient experiencing surgery delay. Fourteen patients exhibit confirmed radiological response, with 44% achieving major pathological response (MPR) and no pathological complete response (pCR). Similar genomic alterations are observed before and after treatment without influencing the efficacy of subsequent EGFR-tyrosine kinase inhibitors (TKIs) in vitro. Infiltration and T cell receptor (TCR) clonal expansion of CCR8+ regulatory T (Treg)hi/CXCL13+ exhausted T (Tex)lo cells define a subtype of EGFR-mutant NSCLC highly resistant to immunotherapy, with the phenotype potentially serving as a promising signature to predict immunotherapy efficacy. Informed circulating tumor DNA (ctDNA) detection in EGFR-mutant NSCLC could help identify patients nonresponsive to neoadjuvant immunochemotherapy. These findings provide supportive data for the utilization of neoadjuvant immunochemotherapy and insight into immune resistance in EGFR-mutant NSCLC.

A pseudo-icosahedral cage {Gd12} based on aminomethylphosphonate.

Reaction of (aminomethyl)phosphonic acid (ampH2) with a mixture of gadolinium and cobalt pivalates under solvothermal conditions, led to a pseudo-icosahedral cage {Gd12}, which shows a large magnetocaloric effect (MCE).

Magnetocaloric Properties of Heterometallic 3d-Gd Complexes Based on the [Gd(oda)3 ](3-) Metalloligand.

A series of heterometallic 3d-Gd(3+) complexes based on a lanthanide metalloligand, [M(H2 O)6 ][Gd(oda)3 ]⋅3 H2 O [M=Cr(3+) (1-Cr)] (H2 oda=2,2'-oxydiacetic acid), [M(H2 O)6 ][MGd(oda)3 ]2 ⋅3 H2 O [M=Mn(2+) (2-Mn), Fe(2+) (2-Fe) and Co(2+) (2-Co)], and [M3 Gd2 (oda)6 (H2 O)6 ]⋅12 H2 O [M=Ni(2+) (3-Ni), Cu(2+) (3-Cu), and Zn(2+) (3-Zn)], are reported. Magnetic and heat-capacity studies revealed a significant impact on the magnetocaloric effect depending on the anisotropy of the 3d transition metal ions, as confirmed by comparison of the observed maximum values of -ΔSm between complexes 2-Co and 1-Cr. In these two complexes, the 3d metal ions have the same spin (S=3/2 for Co(2+) and Cr(3+) ions), and the theoretical calculation suggested a larger -ΔSm value for 2-Co (47.8 J K(-1) kg(-1) ) than 1-Cr (37.5 J K(-1) kg(-1) ); however, the significant anisotropy of Co(2+) ions in 2-Co, which can result in smaller effective spins, gives a smaller value of -ΔSm for 2-Co (32.2 J K(-1) kg(-1) ) than for 1-Cr (35.4 J K(-1) kg(-1) ) at ΔH=9 T.

Varietal differences in the growth of rice seedlings exposed to perchlorate and their antioxidative defense mechanisms.

A hydroponic experiment was conducted to investigate perchlorate (ClO4 (-) ) phytotoxicity in different rice varieties. Considerable variations were observed when 24 rice varieties were treated with ClO4 (-) . The shoot height, root length, and biomass of most varieties were significantly reduced by ClO4 (-) . The roots were more sensitive than the shoots. Hierarchical clustering analysis demonstrated primarily 4 groups: ClO4 (-) -sensitive, medium ClO4 (-) -sensitive, medium ClO4 (-) tolerant, and ClO4 (-) -tolerant. Gannuoxiang (a ClO4 (-) -tolerant variety) and IR65598-112-2 (a ClO4 (-) -sensitive variety) were chosen to explore their antioxidant response when exposed to 0.2 mmol/L, 2.0 mmol/L, and 4.0 mmol/L ClO4 (-) . The results showed that the activities of superoxide dismutase and catalase increased in the shoots and roots of gannuoxiang with increasing doses of ClO4 (-) , but both of them decreased at higher concentrations of ClO4 (-) in IR65598-112-2. The addition of ClO4 (-) led to a significant increase in peroxidase activities for both of the varieties, whereas the increase was more pronounced in gannuoxiang than in IR65598-112-2. No significant difference was found in malondialdehyde (MDA) contents in gannuoxiang, whereas the addition of ClO4 (-) increased the MDA level significantly in IR65598-112-2. The results indicated that gannuoxiang has higher activities of antioxidant enzymes than IR65598-112-2 to cope with oxidative damage caused by ClO4 (-) stress, which may be the main cause of its high tolerance.

Tuning the spin-crossover behaviour of a hydrogen-accepting porous coordination polymer by hydrogen-donating guests.

A Hoffman-like coordination polymer with appreciable porosity and uncoordinated pyridyl groups, namely, [Fe(2,5-bpp){Au(CN)2}2]⋅x Solv (2,5-bpp = 2,5-bis(pyrid-4-yl)pyridine; Solv = solvent), was synthesised and characterised. A series of fascinating spin-crossover behaviours with abrupt, stepwise and hysteretic features were obtained by exchange with a range of protic solvents (ethanol, n-propanol, isopropyl alcohol, sec-butanol and isobutanol). Guest-host hydrogen-bonding interactions involving the H-accepting site of the framework are primarily responsible for the pronounced cooperativity of these spin-crossover behaviours. Meanwhile, the tunable critical temperatures over a range of about 130 K are presumably attributable to a certain degree of competition between internal pressure and local electronic influences of solvents.

Spin frustration in a family of pillared kagomé layers of high-spin cobalt(II) ions.

Based on the analogous kagomé [Co3 (imda)2 ] layers (imda=imidazole-4,5-dicarboxylate), a family of pillar-layered frameworks with the formula of [Co3 (imda)2 (L)3 ]⋅(L)n ⋅xH2 O (1: L=pyrazine, n=0, x=8; 2: L=4,4'-bipyridine, n=1, x=8; 3: L=1,4-di(pyridin-4-yl)benzene, n=1, x=13; 4: L=4,4'-di(pyridin-4-yl)-1,1'-biphenyl, n=1, x=14) have been successfully synthesized by a hydrothermal/solvothermal method. Single-crystal structural analysis shows a significant increase in the interlayer distances synchronized with the extension of the pillar ligands, namely, 7.092(3) (1), 10.921(6) (2), 14.780(5) (3), and 19.165(4) Š(4). Despite the wrinkled kagomé layers in complexes 2-4, comprehensive magnetic characterizations revealed weakening of interlayer magnetic interactions and an increase in the degree of frustration as the pillar ligand becomes longer from 1 to 4; this leads to characteristic magnetic ground states. For compound 4, which has the longest interlayer distance, the interlayer interaction is so weak that the magnetic properties observed within the range of temperature measured would correspond to the frustrated layer.

Gadolinium oxalate derivatives with enhanced magnetocaloric effect via ionothermal synthesis.

Two new oxalate-bridged Gd(III) coordination polymers, namely, (choline)[Gd(C2O4)(H2O)3Cl]Cl·H2O (1) and [Gd(C2O4)(H2O)3Cl] (2), were first obtained ionothermally by using a deep eutectic solvent (DES). The magnetic studies and heat capacity measurements reveal that the two-dimensional Gd(III)-based coordination polymer of 2 has the higher magnetic density and exhibits a larger cryogenic magnetocaloric effect (MCE) (ΔS(m) = 48 J kg(-1) K(-1) for ΔH = 7 T at 2.2 K).

Guest-effected spin-crossover in a novel three-dimensional self-penetrating coordination polymer with permanent porosity.

Porous and nonporous 3D heterobimetallic coordination polymers based on the 1,4-di(pyridin-4-yl)benzene ligand (dpb), [Fe(dpb){Ag(CN)2}{Ag2(CN)3}]·nSolv (1·nSolv; nSolv = DMF·EtOH, 2DMF·MeCN) and [Fe(dpb)2{Ag(CN)2}2] (2), have been synthesized by diffusion technique, respectively. Single-crystal X-ray analysis shows that 1·nSolv consists of a 3D self-penetrating network with in-situ-generated [Ag2(CN)3](-) species and displays one of the largest volume values of porosity (299 Å(3) per iron atom) after desolvation for the Hoffman-like porous SCO coordination polymers to date. In contrast, nonporous compound 2 is composed of two independent interpenetrated 3D nets with in-situ-generated [Ag(dpb)(CN)2](-) species. Their significant distinctions of structural architectures lead to dramatically different magnetic properties: 1·nSolv displays two-step guest-effected SCO with hysteresis, whereas 2 presents characteristic paramagnetic behavior.

Wheel-shaped nanoscale 3d-4f {Co(II)16Ln(III)24} clusters (Ln = Dy and Gd).

Two unprecedented wheel-shaped nanoscale clusters {Co(II)16Ln(III)24} (Ln = Dy and Gd), with a diameter and a thickness of 3.0 nm and 2.0 nm, respectively, were obtained from the self-assembly of Co(NO3)2, Ln(NO3)3 and a pyridyl-functionalized ß-diketone ligand. Notably, the gadolinium species exhibited a relatively large magnetocaloric effect.

Ionothermal synthesis of two oxalate-bridged lanthanide(III) chains with slow magnetization relaxation by using a deep eutectic solvent.

Two novel isostructural oxalate-bridged lanthanide(III) chains, (choline)[Ln(ox)(H2O)3Cl]Cl·H2O (Ln = Dy/Er), were first obtained ionothermally by using a choline chloride-oxalic acid eutectic mixture as both solvent and structure-directing agent, both of which show field-induced slow relaxation of magnetization.

The first {Dy4} single-molecule magnet with a toroidal magnetic moment in the ground state.

A toroidal magnetic moment in the absence of a conventional total magnetic moment was first observed in a novel tetranuclear dysprosium cluster with nonmagnetic ground state. The toroidal state is quite robust with respect to variations of the exchange parameters.

[Value of microbial gene 16SrRNA in the identification of antenatal infection].

OBJECTIVE: To study the relationship between microbial gene 16SrRNA and intrauterine infection. METHODS: Thirty cases of single preterm birth were enrolled, including 16 cases due to premature rupture of membranes (PROM) (rupture time>18 hrs), 6 cases due to spontaneous preterm birth and 8 cases due to iatrogenic preterm birth. Ten cases of single term birth were used as the control group. Fetal membrane and placenta samples were obtained. Amniotic fluid, blood from cord or newborn babies as well as gastric fluid and tracheal secretions from infants with mechanical ventilation were also obtained. The histological features of placenta and fetal membranes were observed. Polymerase chain reaction (PCR) was used to detect the presence of microbial 16SrRNA and ureaplasma urealyticum (UU) in placenta, fetal membranes and other samples. RESULTS: Twenty-one (70%) cases were diagnosed as chorioamnionitis, characterized by neutrophil infiltration in fetal membrane and placenta tissues, especially in fetal membranes. Chorioamnionitis was most frequent in babies whose gestational age less than 32 weeks or birth weight lower than 1 500 g. Positive 16SrRNA gene was found in 12 cases, and positive UU gene in 10 cases in the preterm birth group. Neither 16SrRNA nor UU gene was detected in the control group. The PROM preterm babies developed more frequent infection than the babies premature born due to other causes, but there were no statistically significant differences in the incidence of infection. CONCLUSIONS: Chorioamnionitis may be the major cause of PROM and premature birth. The detection of microbial genes is valuable in identification of intrauterine infection.

Development of a wide population of chromosome single-segment substitution lines in the genetic background of an elite cultivar of rice (Oryza sativa L.).

Naturally occurring allelic variations underlying complex traits are useful resources for the functional analysis of plant genes. To facilitate the genetic analysis of complex traits and the use of marker-assisted breeding in rice, we developed a wide population consisting of 217 chromosome single-segment substitution lines (SSSLs) using Oryza sativa L. 'Hua-Jing-Xian74' (HJX74), an elite Indica cultivar, as recipient, and 6 other accessions, including 2 Indica and 4 Japonica, as donors. Each SSSL contains a single substituted chromosome segment derived from 1 of the 6 donors in the genetic background of HJX74. The total size of the substituted segments in the SSSL population was 4695.0 cM, which was 3.1 times that of rice genome. To evaluate the potential application of these SSSLs for quantitative trait loci detection, phenotypic variations of the quantitative traits of days to heading and grain length in the population consisting of 210 SSSLs were observed under natural environmental conditions. The results demonstrated that there was a wide range of phenotypic variation in the traits in the SSSL population. These genetic materials will be powerful tools to dissect complex traits into a set of monogenic loci and to assign phenotypic values to different alleles at the locus of interest.

[Genetic analysis of a heading-delayed mutant by T-DNA insertion in rice (Oryza sativa L.)].

Transposon tagging was used to isolate genes in higher plant. In this study, a delayed heading mutant caused by T-DNA insertion in rice was identified. Genetic analysis of the mutant showed that the three types of phenotype, normal heading, delayed heading and overly delayed heading in the segregating populations derived from the T-DNA heterozygotes fit the ratio of 1:2:1. Test for Basta resistance showed the delayed heading plants were all resistant while the normal heading plants were susceptible, and the ratio of resistant and susceptible plants was 3:1, which indicated that the delayed heading mutant was co-segregated with Basta resistance. The delayed heading mutant caused by T-DNA insertion was confirmed by T-DNA detection using PCR method. This delayed heading mutant will be used for isolation of the tagged gene in rice.

[Identification of QTLs on substituted segments in single segment substitution lines of rice].

The quantitative trait loci (QTLs) for 21 traits of agronomy importance on ten substituted chromosomal segments were identified using single segment substitution lines (SSSLs) in rice, which were developed by the use of Taichung 65 as a recipient and zhai-ye-qing and dee-geo-woo-gen as donors respectively. Total length of the substituted segments in the SSSLs was 230.00 cM, which was 12.62% of rice genome. T-test was used to detect QTLs in the condition that the difference in phenotypes between a SSSL and the recipient parent (Taichung 65) was significant at the 0.1% level (P< or = 0.001). A total of 57 QTLs for 17 traits had been detected on the ten substituted segments, which were on chromosomes 1, 3, 5, 7, 8, 10 and 12 respectively. The additive effect percentages of the QTLs ranged from 1.10% to 89.73%. Among of 57 QTLs, fifteen QTLs had the additive effect percentage over 10%, thirty QTLs varied from 3% to 10% and other twelve QTLs were below 3%.