The electrochemistry of stable sulfur isotopes versus lithium.

Sulfur in nature consists of two abundant stable isotopes, with two more neutrons in the heavy one (34S) than in the light one (32S). The two isotopes show similar physicochemical properties and are usually considered an integral system for chemical research in various fields. In this work, a model study based on a Li-S battery was performed to reveal the variation between the electrochemical properties of the two S isotopes. Provided with the same octatomic ring structure, the cyclo-34S8 molecules form stronger S-S bonds than cyclo-32S8 and are more prone to react with Li. The soluble Li polysulfides generated by the Li-34S conversion reaction show a stronger cation-solvent interaction yet a weaker cation-anion interaction than the 32S-based counterparts, which facilitates quick solvation of polysulfides yet hinders their migration from the cathode to the anode. Consequently, the Li-34S cell shows improved cathode reaction kinetics at the solid-liquid interface and inhibited shuttle of polysulfides through the electrolyte so that it demonstrates better cycling performance than the Li-32S cell. Based on the varied shuttle kinetics of the isotopic-S-based polysulfides, an electrochemical separation method for 34S/32S isotope is proposed, which enables a notably higher separation factor than the conventional separation methods via chemical exchange or distillation and brings opportunities to low-cost manufacture, utilization, and research of heavy chalcogen isotopes.

Sodium layered oxide cathodes: properties, practicality and prospects.

Rechargeable sodium-ion batteries (SIBs) have emerged as an advanced electrochemical energy storage technology with potential to alleviate the dependence on lithium resources. Similar to Li-ion batteries, the cathode materials play a decisive role in the cost and energy output of SIBs. Among various cathode materials, Na layered transition-metal (TM) oxides have become an appealing choice owing to their facile synthesis, high Na storage capacity/voltage that are suitable for use in high-energy SIBs, and high adaptivity to the large-scale manufacture of Li layered oxide analogues. However, going from the lab to the market, the practical use of Na layered oxide cathodes is limited by the ambiguous understanding of the fundamental structure-performance correlation of cathode materials and lack of customized material design strategies to meet the diverse demands in practical storage applications. In this review, we attempt to clarify the fundamental misunderstandings by elaborating the correlations between the electron configuration of the critical capacity-contributing elements (e.g., TM cations and oxygen anion) in oxides and their influence on the Na (de)intercalation (electro)chemistry and storage properties of the cathode. Subsequently, we discuss the issues that hinder the practical use of layered oxide cathodes, their origins and the corresponding strategies to address their issues and accelerate the target-oriented research and development of cathode materials. Finally, we discuss several new Na layered cathode materials that show prospects for next-generation SIBs, including layered oxides with anion redox and high entropy and highlight the use of layered oxides as cathodes for solid-state SIBs with higher energy and safety. In summary, we aim to offer insights into the rational design of high-performance Na layered oxide cathode materials towards the practical realization of sustainable electrochemical energy storage at a low cost.

Fluoride-Mediated Aryne 1,2-Difunctionalization Involving C═S Bond Heterolysis.

We have successfully synthesized a series of bidentate ligands by utilizing 2-(trimethylsilyl)phenyl trifluorosulfonate as a precursor for the benzyl group. This method proceeded by inserting a polythiourea into the C═S π-bond, intramolecular ring proton migration, and ring opening. Salient features of this strategy are mild reaction conditions, a novel product structure, excellent stereochemistry, and a good functional group tolerance. Furthermore, a series of density functional theory calculations were performed to gain insights into the transfer mechanism.

A Fully Amorphous, Dynamic Cross-Linked Polymer Electrolyte for Lithium-Sulfur Batteries Operating at Subzero-Temperatures.

Solid-state lithium-sulfur batteries have shown prospects as safe, high-energy electrochemical storage technology for powering regional electrified transportation. Owing to limited ion mobility in crystalline polymer electrolytes, the battery is incapable of operating at subzero temperature. Addition of liquid plasticizer into the polymer electrolyte improves the Li-ion conductivity yet sacrifices the mechanical strength and interfacial stability with both electrodes. In this work, we showed that by introducing a spherical hyperbranched solid polymer plasticizer into a Li+ -conductive linear polymer matrix, an integrated dynamic cross-linked polymer network was built to maintain fully amorphous in a wide temperature range down to subzero. A quasi-solid polymer electrolyte with a solid mass content >90 % was prepared from the cross-linked polymer network, and demonstrated fast Li+ conduction at a low temperature, high mechanical strength, and stable interfacial chemistry. As a result, solid-state lithium-sulfur batteries employing the new electrolyte delivered high reversible capacity and long cycle life at 25 °C, 0 °C and -10 °C to serve energy storage at complex environmental conditions.

Refined Electrolyte and Interfacial Chemistry toward Realization of High-Energy Anode-Free Rechargeable Sodium Batteries.

Anode-free rechargeable sodium batteries represent one of the ultimate choices for the 'beyond-lithium' electrochemical storage technology with high energy. Operated based on the sole use of active Na ions from the cathode, the anode-free battery is usually reported with quite a limited cycle life due to unstable electrolyte chemistry that hinders efficient Na plating/stripping at the anode and high-voltage operation of the layered oxide cathode. A rational design of the electrolyte toward improving its compatibility with the electrodes is key to realize the battery. Here, we show that by refining the volume ratio of two conventional linear ether solvents, a binary electrolyte forms a cation solvation structure that facilitates flat, dendrite-free, planar growth of Na metal on the anode current collector and that is adaptive to high-voltage Na (de)intercalation of P2-/O3-type layered oxide cathodes and oxidative decomposition of the Na2C2O4 supplement. Inorganic fluorides, such as NaF, show a major influence on the electroplating pattern of Na metal and effective passivation of plated metal at the anode-electrolyte interface. Anode-free batteries based on the refined electrolyte have demonstrated high coulombic efficiency, long cycle life, and the ability to claim a cell-level specific energy of >300 Wh/kg.

Mitigating Swelling of the Solid Electrolyte Interphase using an Inorganic Anion Switch for Low-temperature Lithium-ion Batteries.

In overcoming the Li+ desolvation barrier for low-temperature battery operation, a weakly-solvated electrolyte based on carboxylate solvent has shown promises. In case of an organic-anion-enriched primary solvation sheath (PSS), we found that the electrolyte tends to form a highly swollen, unstable solid electrolyte interphase (SEI) that shows a high permeability to the electrolyte components, accounting for quickly declined electrochemical performance of graphite-based anode. Here we proposed a facile strategy to tune the swelling property of SEI by introducing an inorganic anion switch into the PSS, via LiDFP co-solute method. By forming a low-swelling, Li3 PO4 -rich SEI, the electrolyte-consuming parasitic reactions and solvent co-intercalation at graphite-electrolyte interface are suppressed, which contributes to efficient Li+ transport, reversible Li+ (de)intercalation and stable structural evolution of graphite anode in high-energy Li-ion batteries at a low temperature of -20 °C.

[Influence of E-cadherin methylation on prognosis in children with acute lymphoblastic leukemia]. / å„¿ç«¥æ€¥æ€§æ·‹å·´ç»†èƒžç™½è¡€ç— ä¸­E-钙黏蛋白甲基化对预后的影响.

OBJECTIVES: To study the significance of E-cadherin and the association between E-cadherin methylation status and prognosis in children with acute lymphoblastic leukemia (ALL) by examining the mRNA and protein expression of E-cadherin and its gene methylation status in bone marrow mononuclear cells of children with ALL. METHODS: The samples of 5 mL bone marrow blood were collected from 42 children with ALL who were diagnosed for the first time at diagnosis (pre-treatment group) and on day 33 of induction chemotherapy (post-treatment group). RT-qPCR, Western blot, and methylation-specific PCR were used to measure the mRNA and protein expression of E-cadherin and the methylation level of the E-cadherin gene. The changes in each index after induction chemotherapy were compared. RESULTS: The mRNA and protein expression levels of E-cadherin in the post-treatment group were significantly higher than those in the pre-treatment group (P<0.05), while the positive rate of E-cadherin gene methylation in the post-treatment group was significantly lower than that in the pre-treatment group (P<0.05). At the end of the test, the children with negative methylation had significantly higher overall survival rate and event-free survival rate than those with positive methylation (P<0.05). CONCLUSIONS: E-cadherin expression is associated with the development of ALL in children, and its decreased expression and increased methylation level may indicate a poor prognosis.

Visible light-promoted intermolecular cyclization/aromatization of chalcones and 2-mercaptobenzimidazoles via an EDA complex and a mechanism study.

Visible-light-promoted cyclization and aromatization of chalcones with 2-mercaptobenzimidazoles have been successfully developed to obtain diverse imidazo[2,1-b]thiazoles, and C-S and C-N bonds were constructed in one step. The reaction uses oxygen in the air as an oxidant, and the method does not need an external photocatalyst or a transition metal catalyst. The strategy features mild conditions, a simple system, readily accessible feedstocks, and a friendly environment. UV absorption spectroscopy and control experiments have shown that the reaction mechanism involves the formation of an electron-donor-acceptor (EDA) complex from thiolate anions and chalcones. In order to verify the mechanism, we studied the structure and HOMO/LUMO of the EDA complex by density functional theory (DFT) calculations. The results show that the π-π stacking between chalcones and 2-mercaptobenzimidazoles will cause a red shift of the UV absorption wavelength in the presence of Cs2CO3, and also provide a theoretical basis for the electron transfer of EDA complexes.

Hydrogen Isotope Effects on Aqueous Electrolyte for Electrochemical Lithium-Ion Storage.

As two stable hydrogen isotopes, protium and deuterium show magnified isotope effects in physicochemical properties due to the significantly varied atomic masses. In this work, aqueous electrolytes based on heavy water (D2 O) and light water (H2 O) were prepared to reveal the electrochemical isotope effects between the hydrogen isotopes. The covalent hydrogen-oxygen bond and intermolecular hydrogen bond in D2 O are much stronger than those in H2 O, making them thermodynamically more stable. Compared with the H2 O-based electrolyte, the D2 O-based electrolyte shows a broader electrochemical window, a higher percentage of coordinated water and a longer lifetime of hydrogen bond. Because of the above electrochemical isotope effects, the D2 O-based electrolyte shows high anodic stability against operation of high-voltage layered oxide cathode materials including LiCoO2 and LiNi0.8 Co0.1 Mn0.1 O2 , which enables long cycle life and favorable rate performance of aqueous Li-ion batteries.

Competitive Doping Chemistry for Nickel-Rich Layered Oxide Cathode Materials.

Chemical modification of electrode materials by heteroatom dopants is crucial for improving storage performance in rechargeable batteries. Electron configurations of different dopants significantly influence the chemical interactions inbetween and the chemical bonding with the host material, yet the underlying mechanism remains unclear. We revealed competitive doping chemistry of Group IIIA elements (boron and aluminum) taking nickel-rich cathode materials as a model. A notable difference between the atomic radii of B and Al accounts for different spatial configurations of the hybridized orbital in bonding with lattice oxygen. Density functional theory calculations reveal, Al is preferentially bonded to oxygen and vice versa, and shows a much lower diffusion barrier than BIII . In the case of Al-preoccupation, the bulk diffusion of BIII is hindered. In this way, a B-rich surface and Al-rich bulk is formed, which helps to synergistically stabilize the structural evolution and surface chemistry of the cathode.

[Expression and Significance of Leucine-rich Repeat-containing G-protein Coupled Receptor 5/6 in Wnt Pathway in Children with Acute Lymphoblastic Leukemia].

Objective To study the expression and significance of leucine-rich repeat-containing G-protein coupled receptor(LGR)5/6 in childhood acute lymphoblastic leukemia(ALL). Methods A total of 39 children who had ALL and achieved complete remission on day 33 after induction therapy were enrolled.The children before induction therapy were considered as the incipient group,and those who achieved complete remission on day 33 by induction therapy were considered as the remission group.According to the degree of risk,they were assigned into 3 groups:low-risk(n=16),intermediate-risk(n=9),and high-risk(n=14)groups.A total of 30 children with immune thrombocytopenia were taken as the control group.From each child in the incipient group,remission group,and control group,3 ml bone marrow sample was collected.Real-time fluorescent quantitative polymerase chain reaction was conducted to measure the mRNA expression of LGR5 and LGR6 in the blood cells of bone marrow.Western blot was employed to measure the protein expression of LGR5 and LGR6 in blood cells of bone marrow. Results Compared with the control(mRNA:1.541±0.409,protein:0.138±0.041)and remission(mRNA:1.418±0.324,protein:0.130±0.033)groups,the incipient group had significantly lower mRNA(0.850±0.279)and protein(0.083±0.027)expression of LGR5(PmRNA=0.000,Pprotein=0.000).Compared with the control(mRNA:0.928±0.373,protein:0.094±0.037)and remission(mRNA:0.886±0.390,protein:0.111±0.039)groups,the incipient group had significantly higher mRNA(2.444±1.160)and protein(0.298±0.088)expression of LGR6(PmRNA=0.000,Pprotein=0.000).In the incipient groups,low-risk children showed significantly higher mRNA(1.004±0.284)and protein(0.097±0.030)expression of LGR5 than the intermediate-risk children(mRNA:0.728±0.239,protein:0.071±0.022)and high-risk children(mRNA:0.752±0.222,protein:0.074±0.020)(PmRNA=0.012,Pprotein=0.016);low-risk children showed significantly lower mRNA(1.822±0.979)and protein(0.245±0.077)expression of LGR6 than the intermediate-risk children(mRNA:2.954±1.039,protein:0.338±0.081)and high-risk children(mRNA:2.827±1.165,protein:0.333±0.075)(PmRNA=0.016,Pprotein=0.004).In the remission groups,low-risk children showed significantly higher mRNA(1.597±0.329)and protein(0.150±0.035)expression of LGR5 than the intermediate-risk children(mRNA:1.277±0.288,protein:0.117±0.029)and high-risk children(mRNA:1.305±0.253,protein:0.116±0.023)(PmRNA=0.012,Pprotein=0.006);low-risk children showed significantly lower mRNA(0.662±0.334)and protein(0.089±0.034)expression of LGR6 than the intermediate-risk children(mRNA:1.066±0.273,protein:0.130±0.033)and high-risk children(mRNA:1.027±0.405,protein:0.126±0.038)(PmRNA=0.007,Pprotein=0.007). Conclusion The expression of LGR5 and LGR6 are closely related to the occurrence and risk of childhood ALL,but its mechanism needs further study.

Formulating the Electrolyte Towards High-Energy and Safe Rechargeable Lithium-Metal Batteries.

Rechargeable lithium-metal batteries with a cell-level specific energy of >400 Wh kg-1 are highly desired for next-generation storage applications, yet the research has been retarded by poor electrolyte-electrode compatibility and rigorous safety concerns. We demonstrate that by simply formulating the composition of conventional electrolytes, a hybrid electrolyte was constructed to ensure high (electro)chemical and thermal stability with both the Li-metal anode and the nickel-rich layered oxide cathodes. By employing the new electrolyte, Li∥LiNi0.6 Co0.2 Mn0.2 O2 cells show favorable cycling and rate performance, and a 10 Ah Li∥LiNi0.8 Co0.1 Mn0.1 O2 pouch cell demonstrates a practical specific energy of >450 Wh kg-1 . Our findings shed light on reasonable design principles for electrolyte and electrode/electrolyte interfaces toward practical realization of high-energy rechargeable batteries.

Building an Air Stable and Lithium Deposition Regulable Garnet Interface from Moderate-Temperature Conversion Chemistry.

Garnet-type electrolytes suffer from unstable chemistry against air exposure, which generates contaminants on electrolyte surface and accounts for poor interfacial contact with the Li metal. Thermal treatment of the garnet at >700 °C could remove the surface contaminants, yet it regenerates the contaminants in the air, and aggravates the Li dendrite issue as more electron-conducting defective sites are exposed. In a departure from the removal approach, here we report a new surface chemistry that converts the contaminants into a fluorinated interface at moderate temperature <180 °C. The modified interface shows a high electron tunneling barrier and a low energy barrier for Li+ surface diffusion, so that it enables dendrite-proof Li plating/stripping at a high critical current density of 1.4 mA cm-2 . Moreover, the modified interface exhibits high chemical and electrochemical stability against air exposure, which prevents regeneration of contaminants and keeps high critical current density of 1.1 mA cm-2 . The new chemistry presents a practical solution for realization of high-energy solid-state Li metal batteries.

Enabling a Durable Electrochemical Interface via an Artificial Amorphous Cathode Electrolyte Interphase for Hybrid Solid/Liquid Lithium-Metal Batteries.

A hybrid solid/liquid electrolyte with superior security facilitates the implementation of high-energy-density storage devices, but it suffers from inferior chemical compatibility with cathodes. Herein, an optimal lithium difluoro(oxalato)borate salt was introduced to build in situ an amorphous cathode electrolyte interphase (CEI) between Ni-rich cathodes and hybrid electrolyte. The CEI preserves the surface structure with high compatibility, leading to enhanced interfacial stability. Meanwhile, the space-charge layer can be prominently mitigated at the solid/solid interface via harmonized chemical potentials, acquiring promoted interfacial dynamics as revealed by COMSOL simulation. Consequently, the amorphous CEI integrates the bifunctionality to provide an excellent cycling stability, high Coulombic efficiency, and favorable rate capability in high-voltage Li-metal batteries, innovating the design philosophy of functional CEI strategy for future high-energy-density batteries.

Nitriding-Interface-Regulated Lithium Plating Enables Flame-Retardant Electrolytes for High-Voltage Lithium Metal Batteries.

Safety concerns are impeding the applications of lithium metal batteries. Flame-retardant electrolytes, such as organic phosphates electrolytes (OPEs), could intrinsically eliminate fire hazards and improve battery safety. However, OPEs show poor compatibility with Li metal though the exact reason has yet to be identified. Here, the lithium plating process in OPEs and Li/OPEs interface chemistry were investigated through ex situ and in situ techniques, and the cause for this incompatibility was revealed to be the highly resistive and inhomogeneous interfaces. Further, a nitriding interface strategy was proposed to ameliorate this issue and a Li metal anode with an improved Li cycling stability (300 h) and dendrite-free morphology is achieved. Meanwhile, the full batteries coupled with nickel-rich cathodes, such as LiNi0.8 Co0.1 Mn0.1 O2 , show excellent cycling stability and outstanding safety (passed the nail penetration test). This successful nitriding-interface strategy paves a new way to handle the incompatibility between electrode and electrolyte.

[Expression and significance of dishevelled proteins in the Wnt pathway in childhood acute lymphoblastic leukemia].

OBJECTIVE: To study the significance of dishevelled (DVL) proteins in the Wnt signaling pathway in the pathogenesis and prognosis of childhood acute lymphoblastic leukemia (ALL). METHODS: A total of 33 children with new-onset ALL were enrolled as the case group. According to the degree of risk, they were divided into 3 groups: low-risk (n=14), intermediate-risk (n=5) and high-risk (n=14). A total of 29 children with immune thrombocytopenia were enrolled as the control group. At diagnosis and on day 33 of induction therapy, 2 mL bone marrow samples were collected from the case and control groups, and qRT-PCR was used to measure the mRNA expression of DVL1, DVL2 and DVL3 in blood cells of bone marrow. RESULTS: The mRNA expression of DVL1, DVL2 and DVL3 in the case group in the incipient stage was significantly higher than that in the remission stage and the control group (P<0.05). Compared with the control group, the case group had a significant increase in the mRNA expression of DVL2 in the remission stage (P<0.05). The mRNA expression of DVL2 was significantly higher than that of DVL1 and DVL3 in both remission and incipient stages (P<0.05). The high- and intermediate-risk groups had significantly higher mRNA expression of DVL1 and DVL2 than the low-risk group (P<0.05). The mRNA expression of DVL2 was significantly higher than that of DVL1 and DVL3 in the low-, intermediate- and high-risk groups (P<0.05). CONCLUSIONS: The change in the expression of DVL, especially DVL2, in the Wnt signal pathway has certain significance in the pathogenesis and prognosis of childhood ALL.

Hydrazone Phosphaketene as a Synthetic Platform To Obtain Three Classes of 1,2,4-Diazaphosphol Derivatives by Switchable Chemoselectivity Strategies.

We introduce switchable chemoselectivity strategies based on the hydrazone phosphaketene intermediate to synthesize three classes of 1,2,4-diazaphosphol derivatives. First, the five-membered heterocyclic P and O anion intermediates acted as nucleophilic agents in the selective construction of C-P and C-O bonds. Second, the phosphinidene served as a phosphorus synthon, allowing for the formation of C-P and C-N bonds. Finally, a stepwise mechanism, supported by DFT calculations, was invoked to explain the reaction selectivity.

Role of deubiquitinase JOSD2 in the pathogenesis of esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a deadly malignancy with limited treatment options. Deubiquitinases (DUBs) have been confirmed to play a crucial role in the development of malignant tumors. JOSD2 is a DUB involved in controlling protein deubiquitination and influencing critical cellular processes in cancer. AIM: To investigate the impact of JOSD2 on the progression of ESCC. METHODS: Bioinformatic analyses were employed to explore the expression, prognosis, and enriched pathways associated with JOSD2 in ESCC. Lentiviral transduction was utilized to manipulate JOSD2 expression in ESCC cell lines (KYSE30 and KYSE150). Functional assays, including cell proliferation, colony formation, drug sensitivity, migration, and invasion, were performed, revealing the impact of JOSD2 on ESCC cell lines. JOSD2's role in xenograft tumor growth and drug sensitivity in vivo was also assessed. The proteins that interacted with JOSD2 were identified using mass spectrometry. RESULTS: Preliminary research indicated that JOSD2 was highly expressed in ESCC tissues, which was associated with poor prognosis. Further analysis demonstrated that JOSD2 was upregulated in ESCC cell lines compared to normal esophageal cells. JOSD2 knockdown inhibited ESCC cell activity, including proliferation and colony-forming ability. Moreover, JOSD2 knockdown decreased the drug resistance and migration of ESCC cells, while JOSD2 overexpression enhanced these phenotypes. In vivo xenograft assays further confirmed that JOSD2 promoted tumor proliferation and drug resistance in ESCC. Mechanistically, JOSD2 appears to activate the MAPK/ERK and PI3K/AKT signaling pathways. Mass spectrometry was used to identify crucial substrate proteins that interact with JOSD2, which identified the four primary proteins that bind to JOSD2, namely USP47, IGKV2D-29, HSP90AB1, and PRMT5. CONCLUSION: JOSD2 plays a crucial role in enhancing the proliferation, migration, and drug resistance of ESCC, suggesting that JOSD2 is a potential therapeutic target in ESCC.

[Gestational weight gain and its relationship with the birthweight of offspring].

OBJECTIVE: To explore the appropriate weight gain during pregnancy and its relationship with the birthweight of offspring. METHODS: A total of 16 460 healthy pregnant women who delivered in Beijing Obstetrics and Gynecology Hospital and Haidian Maternity and Child Health Care Hospital in 2010 were recruited. All are singleton pregnancies. Conditions of babies and mothers were recorded, including maternal age, height, prepregnant weight, pregnant weight, gestational weeks on delivery, delivery mode and newborn birthweight. All the pregnant women were divided into underweight, normal weight and overweight group according to their prepregnant body mass index and the criteria of overweight and obesity for Chinese adults.Birthweight between 2500 g and 4000 g was defined as normal birthweight, and 2900 g to 3499 g was defined as appropriate birthweight.Logistic regression model and receiver operating characteristic (ROC) curve analysis were used to explore the recommended gestational weight gain (GWG). RESULTS: (1) The average GWG of the 16 460 women was (17.1 ± 4.9) kg, and the average birthweight of the babies was (3406 ± 400) g. Prevalence of low birthweight and macrosomia was 0.92% (152/16 460) and 7.55% (1 242/16 460), respectively.GWG of underweight (n = 3089), normal weight (n = 11 478) and overweight group (n = 1893) was (17.4 ± 4.6) kg, (17.3 ± 4.8) kg and (15.6 ± 5.3) kg, respectively. And GWG was positively related with the birthweight of offspring (P < 0.01).The differences of GWG, neonatal birthweight and macrosomia prevalence among the three groups are statistically significant (P < 0.01). (2) There are 8449 appropriate birthweight babies in the three groups.For their mothers in the underweight, normal weight and overweight group, the recommended range of GWG were 14.0-19.5 kg, 13.5-19.5 kg and 11.0-18.0 kg, respectively.The recommended GWG for all women was 16.0 kg. (3) According to the recommended GWG, low GWG will increase the risk of low birthweight (OR = 1.589, 95% CI: 1.085-2.326) and reduce the risk of macrosomia (OR = 0.500, 95% CI: 0.401-0.624). Excessive GWG will increase the risk of macrosomia (OR = 2.031, 95% CI:1.789-2.306), but will not lower the risk of low birthweight (OR = 1.168, 95% CI:0.774-1.764). (4) For the underweight, normal weight and overweight group, the range of GWG obtained by the receiver operating characteristic (ROC) curve analysis were 16.3-16.7 kg, 15.6-17.8 kg and 14.6-15.1 kg.For all the three groups, the range was 15.6-16.7 kg.The ranges obtained by the ROC curve analysis were all within the recommended range. CONCLUSION: The GWG was positively associated with the birthweight of offspring, and the appropriate GWG was around 16.0 kg.

[High resolution laser transient spectroscopic technology under two-stage light gas-gun loading condition and stability study of shocked benzene].

The present paper reports the high resolution transient Raman laser testing technology under two-stage light gas-gun loading experiment, and its application to studying the Raman spectroscopy of shocked benzene. In the experiments, the frequency shift of C-C stretching vibration (992 cm(-1)) and C-H stretching vibration peak (3 061 cm(-1)) in the low pressure section (less than 8 GPa) varies linearly with the pressure, and the results agree well with reported data in the literature. The structural changes in liquid benzene about 13 GPa were clarified firstly by the Raman spectral technique; the experimental results show that at a pressure of 9.7 GPa, the structural change of liquid benzene has taken place, not reported in the literature about 13 GPa. But the composition in the production is not clear. The measurement system provides an effective means to study the microstructure changes of transparent and translucent material under dynamic loading experiment.