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1.
Cancer Med ; 13(12): e7328, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38924332

ABSTRACT

BACKGROUND: Sarcopenia is highly prevalent among patients with colorectal cancer (CRC). Computed tomography (CT)-based assessment of low skeletal muscle index (SMI) is widely used for diagnosing sarcopenia. However, there are conflicting findings on the association between low SMI and overall survival (OS) in CRC patients. The objective of this study was to investigate whether CT-determined low SMI can serve as a valuable prognostic factor in CRC. METHODS: We collected data from patients with CRC who underwent radical surgery at our institution between June 2020 and November 2021. The SMI at the third lumbar vertebra was calculated using CT scans, and the cutoff values for defining low SMI were determined using receiver operating characteristic curves. Univariate and multivariate analyses were performed to assess the associations between clinical characteristics and postoperative major complications. RESULTS: A total of 464 patients were included in the study, 229 patients (46.7%) were classified as having low SMI. Patients with low SMI were older and had a lower body mass index (BMI), a higher neutrophil to lymphocyte ratio (NLR), and higher nutritional risk screening 2002 (NRS2002) scores compared to those with normal SMI. Furthermore, patients with sarcopenia had a higher rate of major complications (10.9% vs. 1.3%; p < 0.001) and longer length of stay (9.09 ± 4.86 days vs. 8.25 ± 3.12 days; p = 0.03). Low SMI and coronary heart disease were identified as independent risk factors for postoperative major complications. Moreover, CRC patients with low SMI had significantly worse OS. Furthermore, the combination of low SMI with older age or TNM stage II + III resulted in the worst OS in each subgroup analysis. CONCLUSIONS: CT-determined low SMI is associated with poor prognosis in patients with CRC, especially when combined with older age or advanced TNM stage.


Subject(s)
Colorectal Neoplasms , Muscle, Skeletal , Sarcopenia , Tomography, X-Ray Computed , Humans , Male , Female , Colorectal Neoplasms/surgery , Colorectal Neoplasms/pathology , Colorectal Neoplasms/mortality , Colorectal Neoplasms/complications , Colorectal Neoplasms/diagnostic imaging , Sarcopenia/diagnostic imaging , Aged , Tomography, X-Ray Computed/methods , Prognosis , Middle Aged , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/pathology , Postoperative Complications/epidemiology , Retrospective Studies , Body Mass Index , ROC Curve
2.
Inorg Chem ; 63(26): 12342-12349, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38904258

ABSTRACT

As a typical RNA virus, the genetic information on HIV-1 is entirely stored in RNA. The reverse transcription activity of HIV-1 reverse transcriptase (RT) plays a crucial role in the replication and transmission of the virus. Non-nucleoside RT inhibitors (NNRTIs) block the function of RT by binding to the RNA binding site on RT, with very few targeting viral RNA. In this study, by transforming planar conjugated ligands into a spiro structure, we convert classical Ru(II) DNA intercalators into a nonintercalator. This enables selective binding to HIV-1 transactivation response (TAR) RNA on the outer side of nucleic acids through dual interactions involving hydrogen bonds and electrostatic attraction, effectively inhibiting HIV-1 RT and serving as a selective fluorescence probe for TAR RNA.


Subject(s)
HIV Reverse Transcriptase , HIV-1 , Reverse Transcriptase Inhibitors , Ruthenium , HIV Reverse Transcriptase/antagonists & inhibitors , HIV Reverse Transcriptase/metabolism , Reverse Transcriptase Inhibitors/chemistry , Reverse Transcriptase Inhibitors/pharmacology , Reverse Transcriptase Inhibitors/metabolism , Ligands , HIV-1/enzymology , HIV-1/drug effects , Ruthenium/chemistry , Ruthenium/pharmacology , RNA, Viral/metabolism , RNA, Viral/chemistry , Spiro Compounds/chemistry , Spiro Compounds/pharmacology , Spiro Compounds/metabolism , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Coordination Complexes/chemical synthesis , Intercalating Agents/chemistry , Intercalating Agents/pharmacology , Molecular Structure , Humans , Anti-HIV Agents/chemistry , Anti-HIV Agents/pharmacology , HIV Long Terminal Repeat , Binding Sites
3.
Expert Rev Anti Infect Ther ; 22(5): 353-363, 2024 May.
Article in English | MEDLINE | ID: mdl-38251634

ABSTRACT

OBJECTIVE: With the change in drug-resistant pattern, MDR/RR-TB was faced with underlying changes in regimens. A multi-center, large-scale, retrospective study performed aims to provide a recommendation of drug selection on optimization of outcome for the patients. METHOD: The study was conducted in six TB-specialized hospitals in China. Patients were included from 2018-2021 and followed up throughout the treatment. Using a multivarariable and propensity score-matched logistic regression analysis, we evaluated associations between outcomes and drug use, as well as clinical characteritics. RESULTS: Of 3112 patients, 74.29% had treatment sucess, 14.52% lost to follow-up, 9.67% failure, and 1.51% died. Treatment success was positively associated with Bedaquiline(Bdq), Linezolid(Lzd), and Cycloserin(Cs). Capreomycin(Cm) increased the risk of unfavorable outcomes. other drugs such as Amikacin(Amk) and clofazimine had no significant effect on outcomes. If isolates were susceptible to fluoroquinolones(FQs), FQs could decrease the risk of unfavorable outcomes. CONCLUSIONS: The recommendation order for the treatment of MDR/RR-TB is Bdq, Lzd, and Cs. FQs were decreased in use intensity. Injection drugs, whether Amk or Cm, are not recommended.


Subject(s)
Antitubercular Agents , Tuberculosis, Multidrug-Resistant , Humans , Retrospective Studies , China , Antitubercular Agents/administration & dosage , Antitubercular Agents/pharmacology , Tuberculosis, Multidrug-Resistant/drug therapy , Male , Female , Middle Aged , Adult , Treatment Outcome , Cohort Studies , Aged , Young Adult , Follow-Up Studies , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/isolation & purification , Lost to Follow-Up
4.
J Colloid Interface Sci ; 660: 440-448, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38244509

ABSTRACT

This study employed a one-step hydrothermal process to synthesize Ni3S2/Fe3O4 nanoblocks in situ on nickel foam (NF). The resulting Ni3S2/Fe3O4/NF catalyst demonstrates exceptional electrocatalytic activity for the oxygen evolution reaction (OER) and robust long-term stability. It achieves a low overpotential of only 220 mV for a current density of 10 mA cm-2 with a Tafel slope of 54.1 mV dec-1 and remains stable in 1.0 M KOH for 66 h. The binder-free self-supported three-dimensional nanoblocks enhance the reaction region and long-term stability. Electronic interactions between Fe3O4 and Ni3S2, coupled with heterogeneous interfaces, optimize the electronic structure, fostering the formation of highly reactive species. Density-functional theory (DFT) calculations confirm that Ni3S2/Fe3O4, with a heterogeneous interfacial structure, modulates the chemisorption of reaction intermediates on the catalyst surface, optimizing the Gibbs free energies (ΔG) of oxygen-containing intermediates. The synergistic effect between the two active materials within the heterogeneous structure enhances OER catalytic performance. This finding offers a valuable approach to designing efficient and stable OER electrocatalysts.

5.
Langmuir ; 40(3): 1902-1908, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38194665

ABSTRACT

Self-assemblies of two fluorenone-based derivatives (FE and FEC) consisting of a central 2,7-diphenyl-9-fluorenone polar moiety but differing in the flexible terminal groups were investigated by scanning tunneling microscopy (STM) at the 1-octanoic acid/HOPG interface under different concentrations and density functional theory calculation (DFT). STM results reveal a concentration-dependent polymorphic self-assembly behavior for FE, but without the presence of co-adsorbed solvents. As the concentration decreases, the dimer, bracket-like, and ribbon-like self-assembled structures were observed. On the contrary, FEC molecules assemble into only a type of oval-shaped morphology by the intermolecular N···H-O hydrogen bonds with the solvent molecules. Combined with DFT calculations, it can be deduced that the intermolecular van der Waals forces, dipole-dipole interactions, and hydrogen bonding are the main driving forces to stabilize the molecular packing of fluorenone-based polycatenars with strong polarity. Our work is of significance at the molecular level to further clarify the intermolecular interactions and conformational effects on the formation of molecular packing structures with liquid crystal property.

6.
RSC Adv ; 13(50): 35621-35628, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-38077974

ABSTRACT

Anaerobic digestion can help mitigate tobacco waste (TW) pollution. Both the mono-digestion of sludge and the co-digestion of TW and sludge were considered in this study. Additionally, the effects of nano-Al2O3 and multi-walled carbon nanotubes (MWCNTs) on these two digestion systems were investigated through a 35 day digestion experiment. The microbial communities in the control reactors and the nano-Al2O3 reactors were also examined. Kinetic analysis revealed that the Rm values for the mono- and co-digestion nano-Al2O3 reactors increased by 8.88% and 13.5% compared with that of the MWCNTs reactor, respectively. Furthermore, the co-digestion system exhibited a 34.8% higher Rm than the mono-digestion system when nano-Al2O3 was added to both systems. Nano-Al2O3 was found to shorten the lag phase, while MWCNTs prolonged the lag phase time. Furthermore, 16S RNA amplicon sequencing results indicated that microbial species such as Methanobacterium sp., Hydrogenispora sp., Lutispora sp., and Ruminiclostridium sp. were more abundant in the nano-Al2O3 reactor. These results demonstrated that biogas production in co-digestion systems was improved. Moreover, nano-Al2O3 addition enhanced biogas production.

7.
J Fluoresc ; 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-37987983

ABSTRACT

Novel fluorescent probes were constructed for the convenient and rapid analysis of Cu2+ ions, taking advantages of the the triphenylamine backbone as chromophore and acylhydrazone group as the Cu2+ recognition site. Especially, probe T2 could act as a dual-channel probe towards Cu2+ through both fluorescent and colorimetric method. Through the fluorescent method, the detection limit of probe T2 was calculated to be as low as 90 nmol/L and there was a good linear relationship between the intensity change and the concentration of Cu2+ ions. By virtue of the two-phase liquid-liquid extraction method, probe T2 could be successfully applied in practical extraction and separation of Cu2+. Furthermore, by applying a "turn-off-turn-on" circle, compound T2 could act as a sensitive probe towards S2- anions through the indirect approach and the detection limit of complex T2-Cu2+ for S2- anion was found to be 110 nmol/L.

8.
Front Endocrinol (Lausanne) ; 14: 1273878, 2023.
Article in English | MEDLINE | ID: mdl-38027124

ABSTRACT

Introduction: Lipidomics elucidates the roles of lipids in both physiological and pathological processes, intersecting with many diseases and cellular functions. The maintenance of lipid homeostasis, essential for cell health, significantly influences the survival, maturation, and functionality of sperm during fertilization. While capacitation and the acrosome reaction, key processes before fertilization, involve substantial lipidomic alterations, a comprehensive understanding of the changes in human spermatozoa's lipidomic profiles during these processes remains unknown. This study aims to explicate global lipidomic changes during capacitation and the acrosome reaction in human sperm, employing an untargeted lipidomic strategy using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Methods: Twelve semen specimens, exceeding the WHO reference values for semen parameters, were collected. After discontinuous density gradient separation, sperm concentration was adjusted to 2 x 106 cells/ml and divided into three groups: uncapacitated, capacitated, and acrosome-reacted. UPLC-MS analysis was performed after lipid extraction from these groups. Spectral peak alignment and statistical analysis, using unsupervised principal component analysis (PCA), bidirectional orthogonal partial least squares discriminant analysis (O2PLS-DA) analysis, and supervised partial least-squares-latent structure discriminate analysis (PLS-DA), were employed to identify the most discriminative lipids. Results: The 1176 lipid peaks overlapped across the twelve individuals in the uncapacitated, capacitated, and acrosome-reacted groups: 1180 peaks between the uncapacitated and capacitated groups, 1184 peaks between the uncapacitated and acrosome-reacted groups, and 1178 peaks between the capacitated and acrosome-reacted groups. The count of overlapping peaks varied among individuals, ranging from 739 to 963 across sperm samples. Moreover, 137 lipids had VIP values > 1.0 and twenty-two lipids had VIP > 1.5, based on the O2PLS-DA model. Furthermore, the identified twelve lipids encompassed increases in PI 44:10, LPS 20:4, LPA 20:5, and LPE 20:4, and decreases in 16-phenyl-tetranor-PGE2, PC 40:6, PS 35:4, PA 29:1, 20-carboxy-LTB4, and 2-oxo-4-methylthio-butanoic acid. Discussion: This study has been the first time to investigate the lipidomics profiles associated with acrosome reaction and capacitation in human sperm, utilizing UPLC-MS in conjunction with multivariate data analysis. These findings corroborate earlier discoveries on lipids during the acrosome reaction and unveil new metabolites. Furthermore, this research highlights the effective utility of UPLC-MS-based lipidomics for exploring diverse physiological states in sperm. This study offers novel insights into lipidomic changes associated with capacitation and the acrosome reaction in human sperm, which are closely related to male reproduction.


Subject(s)
Acrosome Reaction , Lipidomics , Humans , Male , Acrosome Reaction/physiology , Semen , Chromatography, Liquid , Sperm Capacitation/physiology , Tandem Mass Spectrometry , Spermatozoa/physiology , Lipids
9.
Front Endocrinol (Lausanne) ; 14: 1233986, 2023.
Article in English | MEDLINE | ID: mdl-37867530

ABSTRACT

The influence of SARS-CoV-2 infection on clinical outcomes in patients undergoing in vitro fertilization has been uncertain. Therefore, this systematic review and meta-analysis aimed to evaluate the impact of past SARS-CoV-2 infection on IVF outcomes. A comprehensive search of PubMed, EMBASE, and Cochrane Library databases was conducted from December 2019 to January 2023. Included studies comparing IVF outcomes between patients with prior SARS-CoV-2 infection and controls without previous infection were analyzed. Study quality was assessed using the Newcastle-Ottawa Quality Assessment Scale. Sensitivity analysis, publication bias, and heterogeneity were also examined. The review protocol was registered with PROSPERO (CRD42023392007). A total of eight studies, involving 317 patients with past SARS-CoV-2 infection and 904 controls, met the inclusion criteria. The meta-analysis revealed no significant differences between the infection group and controls in terms of clinical pregnancy rate (OR 0.97, 95% CI 0.73-1.29; P = 0.82), implantation rate (OR 0.99, 95% CI 0.67-1.46; P = 0.96), or miscarriage rate (OR 0.64, 95% CI 0.15-2.65; P = 0.53). Subgroup analyses based on transfer type demonstrated comparable clinical pregnancy rates between the two groups in both fresh embryo transfer (OR 0.97, 95% CI 0.69-1.36; P = 0.86) and frozen embryo transfer (OR 0.96, 95% CI 0.38-2.44; P = 0.94). In conclusion, this meta-analysis suggests that previous SARS-CoV-2 infection does not have a detrimental impact on clinical outcomes in IVF patients. These findings provide valuable insights into assessing the influence of prior SARS-CoV-2 infection on successful pregnancy outcomes in IVF treatment. The systematic review was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. This review was prospectively registered with the International Prospective Register of Systematic Reviews (ID CRD42023392007) on January 16, 2023.


Subject(s)
COVID-19 , Live Birth , Pregnancy , Female , Humans , COVID-19/therapy , SARS-CoV-2 , Fertilization in Vitro/methods , Pregnancy Outcome/epidemiology
10.
Reprod Biol Endocrinol ; 21(1): 93, 2023 Oct 21.
Article in English | MEDLINE | ID: mdl-37865766

ABSTRACT

The application of laser technology in the field of assisted reproductive technology (ART) has experienced rapid growth over the past decades owing to revolutionary techniques such as intracytoplasmic sperm injection (ICSI), preimplantation genetic testing (PGT), and in vitro manipulation of gametes and embryos. For male gametes, in vitro manipulation techniques include spermatozoa selection, sorting, immobilization, and quality assessment. A number of studies have been conducted to investigate the application of different laser technologies in the manipulation of human spermatozoa. However, there is a lack of a unified understanding of laser application in the in vitro manipulation of sperm and safety considerations in ART and, subsequently, the inability to make clear and accurate decisions on the clinical value of these laser technologies. This review summarizes the advancements and improvements of laser technologies in the manipulation of human spermatozoa, such as photobiomodulation therapy, laser trap systems for sperm analysis and sorting, laser-assisted selection of immotile sperm and laser-assisted immobilization of sperm prior to ICSI. The safety of those technologies used in ART is also discussed. This review will provide helpful and comprehensive insight into the applications of laser technology in the manipulation of human spermatozoa.


Subject(s)
Semen , Spermatozoa , Humans , Male , Sperm Injections, Intracytoplasmic , Sperm Motility , Lasers
11.
Biomed Chromatogr ; 37(11): e5735, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37651752

ABSTRACT

Cannabidiol has potential for use in skin disease therapy, so it is important to know the cutaneous biodistribution of cannabidiol after topical application of cannabidiol formulations. However, currently existing quantification methods for the investigation of cannabidiol skin distribution are not optimal. This study aimed to establish a method for the determination of cannabidiol in skin samples by UHPLC-MS/MS. A BEH C18 (50.0 × 2.1 mm, 2.5 µm) column was used; the mobile phase consisted of acetonitrile-0.1% formic acid (70:30, v/v), the flow rate was 0.2 µl·min-1 and the column temperature was 30°C. Positive-ion mode with multiple reaction monitoring detection was used to quantify cannabidiol (m/z 315.1 → 193.1) while diphenhydramine (m/z 256.3 → 167.08) served as the internal standard. Good linearity was shown in the range of 1-200 ng·ml-1 for cannabidiol with correlation coefficients of >0.999. The LLOQ was 1 ng·ml-1 . The intra-day and inter-day RSDs of cannabidiol were all <2%. A cryo-sectioning technique combined with the UHPLC-MS/MS method was used to successfully determine cannabidiol levels in a series of very thin skin layers.

12.
Org Lett ; 25(30): 5630-5635, 2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37474500

ABSTRACT

Herein, we demonstrate the successful utilization of copper catalysis and oxygen oxidation for consecutive C(sp3)-C(sp3) bond cleavage in alkyl cyclic ethers. A key step involves a copper-oxygen autoxidation process, generating in situ alkoxy radicals and triggering sequential C-C bond cleavage. This ß-oxidative cleavage strategy enables the use of cyclic ethers as valuable C1 building blocks for the synthesis of bridged methylene dimers. This reaction holds promise for inspiring alternative methods targeting inert C(sp3)-C(sp3) bond cleavage.

13.
Int J Mol Sci ; 24(11)2023 May 26.
Article in English | MEDLINE | ID: mdl-37298292

ABSTRACT

Two series of novel synthesized hexacatenars, O/n and M/n, containing two thiophene-cyanostilbene units interconnected by central fluorene units (fluorenone or dicyanovinyl fluorene) using a donor-acceptor-acceptor-donor (A-D-A-D-A) rigid core, with three alkoxy chains at each end, can self-assemble into hexagonal columnar mesophases with wide liquid crystal (LC) ranges and aggregate into organogels with flowerlike and helical cylinder morphologies, as revealed via POM, DSC, XRD and SEM investigation. Furthermore, these compounds were observed to emit yellow luminescence in both solution and solid states which can be adopted to manufacture a light-emitting liquid crystal display (LE-LCD) by doping with commercially available nematic LC.


Subject(s)
Liquid Crystals , Fluorenes , Gels , Thiophenes
14.
J Colloid Interface Sci ; 639: 416-423, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36812857

ABSTRACT

The development of inexpensive, high efficiency electrocatalysts is a major challenge for electrolytic water to hydrogen production. Herein, an efficient porous nanoblock catalyst N-doped Fe2O3/NiTe2 heterojunction for overall water splitting is reported. Notably, the obtained 3D self-supported catalysts exhibit good hydrogen evolution. reaction (HER) activity and oxygen evolution reaction (OER) properties in alkaline solution (only 70 mV and 253 mV of overpotential are needed to provide 10 mA cm-2 current density, respectively). This is mainly due to the N-doped electronic structure optimized, the strong electronic interaction between Fe2O3 and NiTe2 that facilitates rapid electron transfer, the porous structure which allows the catalyst to have large surface area for effective gas release, and their synergistic effect. When used as a dual function catalyst with overall water splitting, it achieved a current density of 10 mA cm-2 under 1.54 V with good durability (at least 42 h). The present work provides a new methodology for the study of high-performance, low-cost, and corrosion-resistant bifunctional electrocatalysts.

15.
ACS Omega ; 7(33): 29086-29099, 2022 Aug 23.
Article in English | MEDLINE | ID: mdl-36033659

ABSTRACT

Helicobacter pylori infection is a leading cause of gastritis and peptic ulcer. Current treatments for H. pylori are limited by the increase in antibiotic-resistant strains and low drug delivery to the infection site, indicating the need for effective delivery systems of antibiotics. Although liposomes are the most successful drug delivery carriers that have already been applied commercially, their acidic stability still stands as a problem. Herein, we developed a novel nanoliposome using cosmetic raw materials of mannosylerythritol lipid-B (MEL-B), soy bean lecithin, and cholesterol, namely, LipoSC-MELB. LipoSC-MELB exhibited enhanced stability under the simulated gastric-acid condition, owing to its strong intermolecular hydrogen-bond interactions caused by the incorporation of MEL-B. Moreover, amoxicillin-loaded LipoSC-MELB (LipoSC-MELB/AMX) had a particle size of approximately 100 nm and exhibited sustained drug release under varying pH conditions (pH 3-7). Besides, LipoSC-MELB/AMX exhibited significantly higher anti-H. pylori and anti-H. pylori biofilm activity as compared with free AMX. Furthermore, LipoSC-MELB was able to carry AMX across the barriers of gastric mucus and H. pylori biofilms. Remarkably, in vivo assays indicated that LipoSC-MELB/AMX was effective in treating H. pylori infection and its associated gastritis and gastric ulcers. Overall, the findings of this study showed that LipoSC-MELB was effective for gastromucosal delivery of amoxicillin to improve its bioavailability for the treatment of H. pylori infection.

16.
Langmuir ; 2022 May 24.
Article in English | MEDLINE | ID: mdl-35609242

ABSTRACT

Bithiophenyl-based diaminotriazine derivatives (2TDT-n, n = 10, 12, 16, and 18) with different chain lengths display colhex/p6mm mesophases. Their supramolecular self-assembled mechanism is investigated using scanning tunneling microscopy (STM) at the 1-octanoic acid/graphite interface at various concentrations. The chain length effect on the two-dimensional adlayers is observed in this system, and 2TDT-n molecules show a structural phase transition from the four-leaf arrangement to the two-row linear nanostructure accompanied by the emergence of molecular isomerization with the increase of the side-chain length. The self-assembled structure of 2TDT-10 is composed of a four-leaf pattern with uniform s-cis conformers. In 2TDT-12, three kinds of nanostructures (bamboo-like, two-row linear pattern-I, and flower-like) are observed. These nanostructures are randomly constituted by cis and trans conformers, and the ratios of the s-cis conformer in three kinds of patterns are 55.7, 42.3, and 62.5%, respectively. Furthermore, when n = 16 and 18, the ratio of the s-cis conformer further decreases to 19.0 and 4.3%, respectively. Those molecules mainly form linear nanostructures consisting of s-trans conformers. Therefore, it is reasonable to conclude that the side-chain length has a great effect on the self-assembled patterns and the molecular conformation of bithiophenyl-based diaminotriazine derivatives. Density functional theory calculations are applied to optimize molecular conformers and assess their single-point energies, showing that the s-cis conformation has higher energy than the s-trans conformer. We speculate that the ratio of two conformers in nanostructures might be similar to that of the liquid crystalline phase.

17.
Nanomaterials (Basel) ; 12(5)2022 Mar 07.
Article in English | MEDLINE | ID: mdl-35269377

ABSTRACT

In this paper, the fabrication and electrical performance optimization of a four-levels vertically stacked Si0.7Ge0.3 channel nanowires gate-all-around transistor are explored in detail. First, a high crystalline quality and uniform stacked Si0.7Ge0.3/Si film is achieved by optimizing the epitaxial growth process and a vertical profile of stacked Si0.7Ge0.3/Si fin is attained by further optimizing the etching process under the HBr/He/O2 plasma. Moreover, a novel ACT@SG-201 solution without any dilution at the temperature of 40 °C is chosen as the optimal etching solution for the release process of Si0.7Ge0.3 channel. As a result, the selectivity of Si to Si0.7Ge0.3 can reach 32.84 with a signature of "rectangular" Si0.7Ge0.3 extremities after channel release. Based on these newly developed processes, a 4-levels vertically stacked Si0.7Ge0.3 nanowires gate-all-around device is prepared successfully. An excellent subthreshold slope of 77 mV/dec, drain induced barrier-lowering of 19 mV/V, Ion/Ioff ratio of 9 × 105 and maximum of transconductance of ~83.35 µS/µm are demonstrated. However, its driven current is only ~38.6 µA/µm under VDS = VGS = -0.8 V due to its large resistance of source and drain (9.2 × 105 Ω). Therefore, a source and drain silicide process is implemented and its driven current can increase to 258.6 µA/µm (about 6.7 times) due to the decrease of resistance of source and drain to 6.4 × 104 Ω. Meanwhile, it is found that a slight increase of leakage after the silicide process online results in a slight deterioration of the subthreshold slope and Ion/Ioff ratio. Its leakage performance needs to be further improved through the co-optimization of source and drain implantation and silicide process in the future.

18.
J Fluoresc ; 32(3): 1135-1141, 2022 May.
Article in English | MEDLINE | ID: mdl-35318546

ABSTRACT

In this work, dual-emissive ratiometric fluorescent system was constructed by the introduction of an ideal internal reference. By virtue of its unique alkalinity, N2H4 could undergo a hydrazinolysis reaction with the ester group of F1, inducing remarkable fluorescence enhancement while the blue fluorescence of the internal reference DPA remained constant. Consequently, the fluorescence intensity ratios (I540/I440) were proportional to the concentrations of N2H4, which was beneficial for the exactly quantitative detection. The skillful strategy granted the sensing system advantages such as relative good solubility in aqueous media, easy-to-design, simple synthesis, large emission shift, good ratiometric response, as well as the successful application in real water samples and cell imaging.


Subject(s)
Fluorescent Dyes , Hydrazines , Diagnostic Imaging , Spectrometry, Fluorescence , Water
19.
Math Biosci Eng ; 19(4): 4260-4276, 2022 02 25.
Article in English | MEDLINE | ID: mdl-35341297

ABSTRACT

OBJECTIVE: To explore the soft ultrasound marker (USM) combined with non-invasive prenatal testing (NIPT) in diagnosing fetal chromosomal abnormalities based on machine learning and data mining techniques. METHODS: To analyze the data of ultrasonic examination from 856 cases with high-risk single pregnancy during early and middle pregnancy stage. NIPT was applied in 642 patients. All 856 patients accepted amniocentesis and chromosome karyotype analysis to determine the efficacy of USM, Down's syndrome screening, and NIPT in detecting fetal chromosomal abnormalities. RESULTS: Among the 856 fetuses, 129 fetuses (15.07%) with single positive USM and 36 fetuses (4.21%) with two or more positive USM. There were 81 fetuses (9.46%) with chromosomal abnormalities. In the group with multiple USM, chromosomal abnormalities were found in 36.11% of them. It was higher than the group without USM, which was 6.22% (P < 0.01), and the group with just a single USM (19.38%, P < 0.05). The sensitivity, specificity and accuracy were 96.72%, 98.45% and 98.29% when the combination of USM, Down's syndrome screening and NIPT was used to diagnose fetal chromosomal abnormalities further evaluating the accuracy and effectiveness of the above diagnostic criteria and methods with mainstream Classifiers based evaluation indicators of accuracy, f1 score, AUC. CONCLUSIONS: The combination of USM, Down's syndrome screening and NIPT is valuable for the diagnosis of fetal chromosomal abnormalities.


Subject(s)
Down Syndrome , Biomarkers , Chromosome Aberrations , Down Syndrome/diagnosis , Down Syndrome/genetics , Female , Fetus/diagnostic imaging , Humans , Machine Learning , Pregnancy , Prenatal Diagnosis/methods
20.
Nat Commun ; 13(1): 384, 2022 01 19.
Article in English | MEDLINE | ID: mdl-35046396

ABSTRACT

Helical structures continue to inspire, prompted by examples such as DNA double-helix and alpha-helix in proteins. Most synthetic polymers also crystallize as helices, which relieves steric clashes by twisting, while keeping the molecules straight for their ordered packing. In columnar liquid crystals, which often display useful optoelectronic properties, overall helical chirality can be induced by inclusion of chiral chemical groups or dopants; these bias molecular twist to either left or right, analogous to a magnetic field aligning the spins in a paramagnet. In this work, however, we show that liquid-crystalline columns with long-range helical order can form by spontaneous self-assembly of straight- or bent-rod molecules without inclusion of any chiral moiety. A complex lattice with Fddd symmetry and 8 columns per unit cell (4 right-, 4 left-handed) characterizes this "antiferrochiral" structure. In selected compounds it allows close packing of their fluorescent groups reducing their bandgap and giving them promising light-emitting properties.

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